Shaft drive lawn mowers. Comparing Kubota Lawn Tractors

US4117652A. Transmission for self-propelled, walking lawn mowers. Google Patents

Publication number US4117652A US4117652A US05/728,044 US72804476A US4117652A US 4117652 A US4117652 A US 4117652A US 72804476 A US72804476 A US 72804476A US 4117652 A US4117652 A US 4117652A Authority US United States Prior art keywords housing clutch dog drive output shaft mower Prior art date 1976-09-30 Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) Expired. Lifetime Application number US05/728,044 Inventor Ronald N. Jones Devin R. Cline Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.) Dana Inc J B Foote Foundry Co Original Assignee J B Foote Foundry Co Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.) 1976-09-30 Filing date 1976-09-30 Publication date 1978-10-03 1976-09-30 Application filed by J B Foote Foundry Co filed Critical J B Foote Foundry Co 1976-09-30 Priority to US05/728,044 priority Critical patent/US4117652A/en 1977-06-13 Priority to CA280,354A priority patent/CA1068944A/en 1978-10-03 Application granted granted Critical 1978-10-03 Publication of US4117652A publication Critical patent/US4117652A/en 1989-01-03 Assigned to DANA CORPORATION, 4500 DORR ST., A CORP. OF VA reassignment DANA CORPORATION, 4500 DORR ST., A CORP. OF VA ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: FOOTE INDUSTRIES, INC. 1996-09-30 Anticipated expiration legal-status Critical Status Expired. Lifetime legal-status Critical Current

Links

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• 230000001808 coupling Effects 0.000 abstract description 10
• 238000010168 coupling process Methods 0.000 abstract description 10
• 238000005859 coupling reaction Methods 0.000 abstract description 10
• 230000000694 effects Effects 0.000 abstract description 10
• 238000002485 combustion reaction Methods 0.000 description 4
• 230000004048 modification Effects 0.000 description 4
• 238000006011 modification reaction Methods 0.000 description 4
• 238000007789 sealing Methods 0.000 description 4
• 239000004677 Nylon Substances 0.000 description 2
• 239000000789 fastener Substances 0.000 description 2
• 239000000463 material Substances 0.000 description 2
• 239000002184 metal Substances 0.000 description 2
• 229920001778 nylon Polymers 0.000 description 2
• 239000004033 plastic Substances 0.000 description 2

Images

Classifications

• A — HUMAN NECESSITIES
• A01 — AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
• A01D — HARVESTING; MOWING
• A01D34/00 — Mowers; Mowing apparatus of harvesters
• A01D34/01 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus
• A01D34/412 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus having rotating cutters
• A01D34/63 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus having rotating cutters having cutters rotating about a vertical axis
• A01D34/67 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus having rotating cutters having cutters rotating about a vertical axis hand-guided by a walking operator
• A01D34/68 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus having rotating cutters having cutters rotating about a vertical axis hand-guided by a walking operator with motor driven cutters or wheels
• A01D34/69 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus having rotating cutters having cutters rotating about a vertical axis hand-guided by a walking operator with motor driven cutters or wheels with motor driven wheels

• A — HUMAN NECESSITIES
• A01 — AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
• A01D — HARVESTING; MOWING
• A01D34/00 — Mowers; Mowing apparatus of harvesters
• A01D34/01 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus
• A01D34/412 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus having rotating cutters
• A01D34/63 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus having rotating cutters having cutters rotating about a vertical axis
• A01D34/67 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus having rotating cutters having cutters rotating about a vertical axis hand-guided by a walking operator
• A01D34/68 — Mowers; Mowing apparatus of harvesters characterised by features relating to the type of cutting apparatus having rotating cutters having cutters rotating about a vertical axis hand-guided by a walking operator with motor driven cutters or wheels
• A01D2034/6843 — Control levers on the handle of the mower

• A — HUMAN NECESSITIES
• A01 — AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
• A01D — HARVESTING; MOWING
• A01D2101/00 — Lawn-mowers

• Y — GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
• Y10 — TECHNICAL SUBJECTS COVERED BY FORMER USPC
• Y10T — TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
• Y10T74/00 — Machine element or mechanism
• Y10T74/19 — Gearing
• Y10T74/19642 — Directly cooperating gears
• Y10T74/19698 — Spiral
• Y10T74/19828 — Worm

Abstract

A belt-driven transmission designed particularly for self-propelled, walking lawn mowers is provided. The transmission is mounted on a deck of a mower between a front pair or a rear pair of wheels and is driven through a pulley on the engine drive shaft and a pulley on the transmission connected by a belt. With this arrangement, the engine requires no special power take-off shaft to drive the mower. Consequently, the transmission can be universally applied to many different self-propelled lawn mowers. The new transmission can also be equipped with a deadman’s clutch. Further, it can be provided with a manually-adjustable pulley of variable diameter to provide different speeds and torque for the drive shaft of the driven wheels. Also, in accordance with the invention, the drive shaft has a ratchet coupling device near each driven wheel to provide a differential effect for the wheels when the mower is being turned.

Description

This invention relates to a universal transmission designed particularly for self-propelled, walking lawn mowers.

Heretofore, a self-propelled, walking lawn mower usually had a direct drive connection for the mower blade and for the mower wheels. The speed of the blade and wheels were controlled simultaneously only by the throttle of the engine. Consequently, excessive forward speed or stalling of the motor resulted under some conditions. These self-propelled lawn mowers usually required a special separate power take-off shaft for the internal combustion engine which resulted in a more costly engine and, consequently, in a higher priced mower to the consumer.

The new universal transmission according to the invention has a pulley which is driven through a belt connected to a drive pulley on a single drive shaft of the engine, the mower blade being mounted on or driven by the same drive shaft. The transmission pulley can be of a variable-diameter type which can be selectively controlled by the mower operator to vary the speed of the mower independently of the speed of the mower blade. The universal transmission also has a deadman’s clutch to immediately disengage the transmission if a manually-operated control on the handle of the mower is released.

The drive shaft for the wheels to which the transmission is connected, can be provided near each driven wheel with a ratchet coupling device which enables the wheels to be driven in unison or one turned faster than the other to provide a differential effect. This is particularly important when the mower is being turned or otherwise manipulated along a nonlinear path.

It is, therefore, a principal object of the invention to provide an improved universal transmission for self-propelled lawn mowers.

Another object of the invention is to provide a transmission for self-propelled lawn mowers which is driven by an engine having a single drive shaft which also drives the mower blade.

Yet another object of the invention is to provide a universal, belt-driven transmission for self-propelled walking lawn mowers which is capable of driving the mower at widely varying speeds.

Still another object of the invention is to provide a transmission having a manually-adjustable, variable-diameter pulley on the input shaft.

A further object of the invention is to provide a transmission for self-propelled lawn mowers having a deadman’s clutch for disengaging the transmission.

Yet a further object of the invention is to provide a transmission for self-propelled lawn mowers having a drive shaft equipped with ratchet coupling devices near the driven wheels to provide a differential effect for the wheels.

Many other objects and advantages of the invention will be apparent from the following detailed description of a preferred embodiment thereof, reference being made to the accompanying drawings, in which:

FIG. 1 is a somewhat schematic view in perspective of a self-propelled, walking lawn mower with a transmission embodying the invention;

FIG. 2 is an enlarged, fragmentary view in perspective of a portion of the lawn mower shown in FIG. 1;

FIG. 3 is a plan view of the transmission, with parts removed and parts broken away, to show certain other components;

FIG. 4 is a view on transverse, vertical cross section taken along the line 44 of FIG. 3, but with certain components in a different position;

FIG. 10 is a fragmentary view of a portion of the transmission as shown in FIG. 9, with certain components thereof in a different position;

FIG. 11 is a view in longitudinal, vertical cross section taken through a ratchet coupling device on a drive shaft for the mower wheels;

Referring to FIGS. 1 and 2, a self-propelled, walking lawn mower 20 includes a metal deck 22 with a pair of front wheels 24, 26 and a pair of rear wheels 28, 30, the latter pair being driven in this instance. An internal combustion engine 32 is mounted on a raised portion 34 of the deck 22, the rear of the raised portion 34 being open. The engine 32 has a single, downwardly-depending drive shaft 36 on the end of which is mounted a suitable mower blade 38. A drive pulley or sheave 40 is affixed to intermediate portion of the drive shaft 36 above the main portion of the deck 22. A V- belt 42 connects the drive pulley 40 with a driven pulley 44 of a transmission 46 in accordance with the invention. The transmission 46, in this instance, is affixed in a recess 48 of the deck 22 by fasteners 49 (FIG. 9) to provide the desired alignment for the pulleys 40 and 44.

Referring particularly to FIG. 5, the pulley 44 is mounted on a vertical input shaft 50 of the transmission 46. The shaft is rotatably supported in a lower recess 52 of a lower housing half 54 and extends through a bushing 56 in an upper housing half 58, a gasket 59 being located between the two halves. A worm 60 is suitably affixed to the input shaft 50 and meshes with a worm wheel 62 which is rotatably mounted on an output or drive shaft 64.

The drive shaft 64 is rotatably supported in bushings 66 and 68 (FIG. 4) in the lower housing half 54 and is prevented from longitudinal movement by pins 70 and 72 extending through the shaft and positioned against washers 74 and 76 at opposite ends of the housing. A sealing ring 78 is located in the end of the bushing 68 and is held by a washer 80 and a pin 82 extending through the shaft 64.

The worm wheel 62 has a recess receiving a sealing ring 84 in the end of the bushing 66 and has an annular flange 86 near the opposite end cooperating with an upwardly extending flange 88 in the lower housing half 54. The worm wheel is thereby restrained from longitudinal movement on its shaft 64. Beyond the annular flange 86, the worm wheel 62 has a plurality of axially extending lugs or projections 90.

A clutch dog 92 has a groove 94 receiving a key 96 to cause the dog to rotate with a shaft 64. The dog 92 also has lugs or projections 98 engagable with the lugs 90 to cause the worm wheel 62 to rotate with the shaft when the lugs are engaged. This is accomplished when the clutch dog is moved toward the right, as shown in FIG. 4, through an annular flange 100.

Referring to FIGS. 3, 4, and 6, the clutch dog 92 is moved longitudinally of the driven shaft 64 by a shifter fork 102. The fork 102 includes an upper, generally rectangular block 104 located in a recess 106 formed in the upper housing half 58 with a pair of arcuate ridges 108 and 110 extending down through an opening 112 (FIG. 4) in a divider plate 114 held in the housing half 58. The ridges 108 and 110 form an arcuate groove 115 which receives the flange 100 of the clutch dog 92. The shifter fork 102 and specifically the rectangular block 104 thereof is urged toward the left as viewed in FIG. 3 and 4 by a coil spring 116 having one end received in a shallow notch 118 of the block 104 and another end received in a notch 120 located at the end of the recess 106. The central portion of the block 104 has an integral pin or projection 122 extending upwardly through an opening 124 in the housing half 58. The pin is engaged to move the shifter fork back and forth in the recess 106 to move the clutch dog 92 into and out of engagement with the worm wheel 62.

The shifter fork is moved by an L- shaped lever 126 which has a hole 128 through which a lug 130 extends to pivot the lever to the upper housing half. The lever has an intermediate slot 132 which receives the projection 122 and also has an elongate handle 134 extending beyond the housing half 58. The end of the handle has a hole 136 or other suitable means to receive a flexible line or Bowden cable 138 (FIGS. 1 and 2) which extends upwardly to a lever assembly 140 mounted on an upper portion of a mower handle 142. The lever assembly 142 has a lever 144 which is grasped and pulled by the operator when operating the mower. This action pulls up on the cable 138 to move the lever 126 in a clockwise direction as viewed in FIG. 3. This, in turn, moves the shifter fork 102 to the right as viewed in FIGS. 3 and 4 to cause the clutch dog 92 to engage the worm wheel 62. Whenever the lever 144 is released by the operator, the spring 116 returns the shifter dog 102 to the left hand position and disengages the driven mower wheels 28 and 30 from the engine 32.

If desired, the transmission 46 can incorporate safety provisions to prevent starting of the engine 32 when the transmission is engaged. This can be in the form of a safety switch as shown in U.S. Pat. No. 3,808,914, of Hans Hauser, issued Feb. 5, 1973, for example. The switch is wired into the ignition system of the engine in a manner to enable the engine to be started only when the switch terminals are connected and the transmission is disengaged.

The pulley 44 on the input shaft 50 can be of a variable-diameter type to provide change in the speed and the torque applied to the wheels 28 and 30 through the shaft 64. The pulley 44 then includes an upper stationary half 146 which is affixed to a splined end 148 (FIG. 5) of the input shaft 50 and held by a split ring 150. The pulley also includes a lower half 152 which is mounted for axial movement on the shaft 50 but prevented from rotation by a groove or key way 154 cooperating with a shaft key 156. For the purpose of moving the lower pulley half 152 toward and away from the upper half 146, the upper housing half 58 is provided with a plurality of upwardly extending projections 158 (FIGS. 9 and 10) arranged in a circular pattern around the input shaft 50 and having sloping surfaces 160.

A speed change lever 162 is located above the upper housing half 58 and has a hub 164 with downwardly facing projections 166. The projections 166 are also arranged in a circular pattern around the input shaft 50 and have sloping cam surfaces 168 cooperating with the surfaces 160. A thrust washer 170 (FIGS. 6 and 7) is located between the hub 164 and the lower pulley half 152 to prevent wear of the lever 162 which can be of plastic material, such as nylon. A handle 172 extends outwardly from the hub 164 and beyond the pulley 44, in the direction opposite the direction of the handle 134 of the shift lever 126. The handle 172 has a hole 174 or other suitable means for making a connection with a flexible line or Bowden cable 176 (FIGS. 1 and 2) which extends upwardly to a speed control assembly 178 mounted near the mower handle 142. The assembly 178 has a speed control lever 180 which moves the cable 176 back and forth, holding it in a given place by virtue of a friction fit or detent in the assembly 178.

When the cable 176 is pulled, the handle 172 moves in a counterclockwise direction as viewed in FIG. 8. This causes the lever 162 to move upwardly due to the camming effect of the sloping surfaces 168 and 160. The lower pulley half 152 thereby moves upwardly to increase the effective diameter of the pulley 44. This reduces the rotational speed of the output shaft 64 and the driven wheels 28 and 30, but increases the torque to them. As the diameter of the pulley 44 varies, the belt 42 is maintained taut by an idler pulley 182 (FIG. 2) which is urged outwardly by a suitable spring in a housing 184.

The transmission 46 drives the wheels 28 and 30 through the drive shaft 64 and ratchet coupling devices 186 and 188 (FIG. 2) located at the ends of the drive shaft 64. Referring to FIGS. 11-13, the device 188 includes an inner, drive member 190 and an outer, driven member 192. The member 190 includes a cylindrical body 194 having recesses 196 carrying coiled springs 198 which urge pins 200 outwardly in an axial direction. The body 194 has a central passage 202 which receives the drive shaft 64 with the body being connected to the drive shaft by a transverse pin 204 extending through the shaft and received in notches 206 of the body 194.

The outer member 192 has a cylindrical body 208 with tooth means in the form of pinion gear teeth 210 which mesh with tooth means in the form of gear teeth 212 (FIG. 2) on a disc 214 affixed to the inner surface of the hub of the wheel 30.

The body 208 also has arcuate recesses 216 facing the inner member 190. Each of the recesses 216 has a vertical wall 218 and a sloping bottom 220, with ends of the pins 200 being received in the recesses 216. The body 208 has a passage or central bore 222 which rotatably receives the drive shaft 64 with the body 208 being held against the body 194 by an outer pin 224 and a washer 226. Of course, the pins and recesses could be reversed, if desired.

In normal operation, the inner member 190 moves with the drive shaft 64 with the pins 200 engaging the vertical walls 218 of the recesses 216. Consequently, the outer member 192 is driven by the inner member 190 and drives the wheel 30 forwardly. If the mower should be turned so that the wheel 30 tends to move a farther distance and rotate faster than the wheel 28, the outer member 192 will then rotate faster than the inner member 190 with the pins 200 then cammed up the sloping bottoms 220 of the recesses 216 and received in the next recesses as long as the outer member 192 continues to rotate faster than the inner member 190. Hence, with this arrangement, a differential effect is obtained so that the wheels can rotate independently, when moving faster, and avoid skidding or wear on the tires.

As shown in FIGS. 3 and 4, the transmission can have a vent 228 in the upper half 58 to prevent undue pressure buildup therein.

Various modifications of the above-described embodiment of the invention will be apparent to those skilled in the art, and it is to be understood that such modifications can be made without departing from the scope of the invention, if they are within the spirit and the tenor of the accompanying claims.

Claims ( 10 )

In combination, a self-propelled rotary lawn mower having a deck, two substantially aligned drive wheels rotatably supported by said deck, a handle extending upwardly from said deck, an engine mounted above said deck and having a drive shaft extending therethrough, a mower blade affixed to said drive shaft below said deck, a drive pulley affixed to said drive shaft above said mower blade, a transmission having a housing, means mounting said transmission on the lawn mower, an input shaft extending upwardly from said housing and having a driven pulley, a belt connecting said drive pulley and said driven pulley, a first gear mounted on said input shaft within said housing, an output shaft mounted in said housing and extending horizontally outwardly beyond opposite sides thereof, a second gear rotatably mounted on said output shaft in said housing and meshing with said first gear, a clutch dog within said housing affixed to said output shaft at one side of said second gear for rotation with said output shaft and for longitudinal movement with respect thereto, said clutch dog having an engaged position engaged with said second gear and a disengaged position spaced from said second gear, a shifter fork carried by said housing and engagable with said clutch dog, a shift lever carried by said housing for moving said shifter fork and said clutch dog between its two positions, said shift lever being movable by remote control means mounted on the handle of said lawn mower, and means on opposite end portions of said output shaft engagable with said two drive wheels of said mower for driving same.

Drive means according to claim 1 characterized by said last-named means each comprises an inner member affixed to and rotatable with said output shaft, an outer member adjacent said inner member and having tooth means engagable with tooth means of the associated wheel, pin means carried by one of said members, resilient means urging said pin means toward the other of said members, the other of said members having a plurality of sloping recesses therein to receive said pin means, whereby said inner member can drive said outer member at the same speed as said inner member and said outer member can rotate at a rate faster than that of said inner member.

Drive means according to claim 1 characterized by said driven pulley comprising a stationary pulley half affixed to said input shaft in a fixed position and a movable pulley half mounted on said input shaft for rotation therewith and for axial movement with respect thereto, and remote control means on the mower handle for moving said movable pulley half toward and away from said stationary pulley half.

Drive means according to claim 1 characterized by resilient means urging said shifter fork and clutch dog toward the disengaged position of said clutch dog, and said remote control means comprising a control lever carried by the handle of said mower and connected to said shift lever by a flexible cable, said control lever being effective to move said shift lever to the engaged position of said clutch dog when said control lever is grasped by an operator.

A compact transmission comprising an input vertical shaft, a worm mounted on said input shaft for rotation therewith, an output shaft, a worm wheel mounted on said output shaft, but rotatably independent thereof and engaged with said worm, a clutch dog mounted on said output shaft to one side of said worm wheel and affixed thereto for rotation with said output shaft and for longitudinal movement with respect thereto, a shifter fork engagable with said clutch dog, lever means engagable with said shifter fork for moving said clutch dog between only two positions, a position engaged with said worm wheel and a position disengaged from said worm wheel, resilient means for urging said shifter fork and said clutch dog toward the disengaged position of said clutch dog, and a remote control lever connected to said lever means to move said lever means to the engaged position of said clutch dog when said control lever is grasped by an operator, and said resilient means moving said shifter fork and said clutch dog toward the disengaged position of said clutch dog when said control lever is not grasped by the operator.

A compact transmission according to claim 5 characterized by said output shaft having means affixed directly to end portions thereof for engaging and driving wheels of a self-propelled power lawn mower.

A compact transmission according to claim 6 characterized by said last-named means each comprising an inner member affixed to and rotatable with said output shaft, an outer member adjacent said inner member and having tooth means engagable with tooth means of the associated wheel, pin means carried by one of said members, resilient means urging said pin means toward the other of said members, the other said members having a plurality of sloping recesses therein to receive said pin means, whereby said inner member can drive said outer member at the same speed as said inner member and said outer member can rotate at a rate faster than that of said inner member.

A compact transmission according to claim 5 characterized by a pulley on said input shaft, said pulley comprising a stationary pulley half affixed to said input shaft in a fixed position, and a movable pulley half mounted on said input shaft for rotation therewith and for axial movement with respect thereto, and remote control means for moving said movable pulley half toward and away from said stationary pulley half.

A transmission comprising a housing, an input shaft extending upwardly from said housing, an output shaft extending from said housing, gear means within said housing connecting said input shaft and said output shaft, a belt pulley on said input shaft above said housing and comprising a stationary pulley half affixed to said input shaft and a movable pulley half mounted on said input shaft between said housing and said stationary pulley half for rotatable movement therewith and for longitudinal movement with respect thereto, and means engagable with said movable pulley half for moving said movable half toward and away from said stationary half, said engagable means comprising projecting means structurally integral with said housing and having sloping walls, a hub having projecting means in the form of sloping walls cooperating with said sloping walls of said housing projecting means to cause said hub to move toward and away from said stationary pulley half when said hub is turned, said hub having an opening through which said input shaft extends, a lever affixed to said hub for turning said hub when said lever is turned, and bearing means located between said hub and said movable pulley half.

In combination, a self-propelled rotary lawn mower having a deck, two substantially aligned drive wheels rotatably supported by said deck, a handle extending upwardly from said deck, an engine mounted above said deck and having a drive shaft extending therethrough, a mower blade affixed to said drive shaft below said deck, a drive pulley affixed to said drive shaft above said mower blade, a transmission having a housing, means mounting said transmission on the lawn mower, an input shaft extending upwardly from said housing and having a driven pulley, a belt connecting said drive pulley and said driven pulley, a first gear mounted on said input shaft within said housing, an output shaft mounted in said housing and extending horizontally outwardly beyond opposite sides thereof, a second gear mounted on said output shaft in said housing and meshing with said first gear, a clutch dog within said housing and having an engaged position engaged with said second gear and a disengaged position spaced from said second gear, a shifter fork carried by said housing and engagable with said clutch dog, a shift lever carried by said housing for moving said shifter fork and said clutch dog between its two positions, resilient means for urging said shifter fork and said clutch dog toward the disengaged position of said clutch dog, a remote control lever connected to said shift lever to move said shift lever to the engaged position of said clutch dog when said control lever is grasped by an operator, said resilient means moving said shifter fork and said clutch dog toward the disengaged position of said clutch dog when said control lever is not grasped by the operator, and means on opposite end portions of said output shaft engagable with said two drive wheels of said mower for driving same.

US05/728,044 1976-09-30 1976-09-30 Transmission for self-propelled, walking lawn mowers Expired. Lifetime US4117652A ( en )

Applications Claiming Priority (1)

Family Applications (1)

Patent Citations (5)

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Owner name: DANA CORPORATION, 4500 DORR ST., A CORP. OF VA, OH

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:FOOTE INDUSTRIES, INC.;REEL/FRAME:005013/0742

Effective date: 19871030

Comparing Kubota Lawn Tractors

Looking for a riding mower? Kubota offers lots of great mowers and lawn tractors to suit a variety of purposes. Everyone’s needs are different ranging between smaller mowers for less land, and larger, more powerful models that can do more than mowing. Choose the right mower, and you can use it in the spring with a lawn roller or in the winter with a front-mounted snowplow. Let’s talk about the different types of lawn tractors as well as a range of Kubota riding mowers to suit different purposes.

Types of Mowers

Before you buy a mower, analyze your needs. Options include traditional riding mowers and lawn tractors, zero turn mowers, and small tractors. Consider the following:

• How much grass do you have? If you have half an acre to mow, a small riding mower gets the job done faster and easier than a push mower. However, if you have a lot of acreage, you’ll probably want something larger that features a wider mower deck to speed the process.
• Is your lawn sloped? Slopes play a big part in the type of mower you’ll need. Zero turn mowers have a high center of gravity, which can make them unsafe on steep hills. Lawn tractors and compact tractors may be a better fit to mow those hills safely.
• Is your terrain packed with lots of obstacles? Lawns with lots of trees, landscaping and other obstacles mean lots of tight turns and lots of backing up to make sure you don’t miss anything. Zero turn mowers feature high maneuverability to make navigating obstacles easier.
• What else do you need besides mowing? For many homeowners, the only real need they have is mowing. If that’s the case, a riding mower will be the best fit. However, gardeners might be interested in lawn tractors that can pull wagons or tillers. People running a small farm may prefer a compact tractor that can not only mow, but use a rotary cutter, a front end loader, and other implements.

We’re mainly concerned about Kubota lawn tractors here, but understand that mowers break down into three types:

Riding Mowers

Riding mowers are the most popular type of mower for mid-sized yards. For most homeowners, these mowers will get the job done. They come standard with a mower deck. Deck widths will vary based on options selected and the size of the mower. Some riding mowers, particularly on the larger end, can be equipped with implements like yard rollers, grass sweepers, sprayers and wagons, making it a versatile tool that can handle any job the average homeowner may need to do.

Zero Turn Mowers

This is the mower of choice if you have a lot of grass to mow or a lot of tight turns and obstacles in your terrain. Traditional riding mowers feature front wheels that turn together when you turn the steering wheel. Zero-turn mowers turn on a dime using dual transmissions driving side wheels independently.

These mowers are typically speedy, averaging six to eight miles per hour compared to the three or four that a riding mower achieves, which lets you mow lots of grass quickly. That’s in addition to the fact that many zero turns offer large mowing decks. Kubota zero turn mowers range between 42 inches and 72 inches while Kubota lawn and garden tractors go between 42 and 54 inches.

The drawback to these mowers is that zero turn mowers can be dangerous on steep slopes. They have an increased risk of tipping, and because they don’t have a dedicated braking system—you have to pull back the levers to stop the mower—they can be difficult to stop if they start to slide. Here’s how some of the top Kubota zero turn mowers compare.

Compact and Subcompact Tractors

This is the ideal choice when you need a lot more than a mower. For many homeowners, though a compact or subcompact tractor is probably too much tractor. Kubota tractors come with a lot of options like choices between turf tires and tires for other uses, plus options for a front end loader. Since they feature three-point linkages and PTO drives on the rear, this means you can use a lot of different types of equipment, including box blades, rear driven mowers, post hole diggers, snow blowers, sweepers, tillers and more.

That’s what makes tractors ideal for hobby farms or homeowners with a lot of land to maintain. If you’re looking at several hundred feet of driveway that needs to be graded each year, or if you need an easier way to clean barn stalls or move earth than a wheelbarrow, these tractors will do it—and they’ll mow your lawn, too.

For the homeowner with an acre or two, remember that bigger the equipment, the harder it is to maneuver. Compact tractors need a larger area to make turns.

What Are The Top 5 Kubota Lawn Tractors?

If you’re looking for a new mower, Kubota a top brand to consider. They offer a lot of options, and they’re built tough. Accidents can happen when you’re mowing. Cheaper mowers don’t place as much emphasis on structural quality, which means the chances of something bending or part of the framework warping when you hit something goes up. Below are five of the best Kubota mowers out there, each ideal for different budgets and different needs.

Kubota T2090BR-42

This is a smaller riding mower, but with a 20 HP Briggs Stratton engine, it still has plenty of power. It has a lot of great features including a ductile cast iron front axle that will stand up to bumps and shocks whereas other mowers with weaker front axles are more likely to bend or break. Mower decks for this model range between 42 and 48 inches. which gives you a nice wide path for a riding mower. Other options are available, like a deluxe high back seat with armrest and suspension for extra comfort while you’re mowing. This lawn tractor also has optional attachments, including a front snow blade, snow blower and grass catcher.

Kubota T2290KW-42

Also a smaller mower, the Kubota T2290KW-42 is ideal for small to mid-sized yards. It has a 21.5 HP Kawasaki engine, which is a step up from the 20 HP engine in the T2090BR-42. It also adds a few features. Cruise control lets you set the right speed and go, and suspension beneath the seat makes the ride more comfortable. Mower deck sizes are available in 42 and 48 inches. As with other models, you can also get a front snow blade, snow blower and grass catcher for this lawn tractor.

Kubota T2290KWT-48

The Kubota T2290KWT-48 is a feature-rich riding mower. It has an updated dash that lets you monitor the mower’s systems and the 21.5 HP engine. This is a comfortable mower, too. Dual arm rests and a suspension seat prevent shocks when you go over bumps and give you a place to rest your arms. There is also a 12-volt power outlet and a slot for your phone so that you can charge while you mow. Available mower decks for this model come in 42-inch and 48-inch sizes.

Kubota GR2120

This heavy-duty mower is designed for small to mid-sized yards. It features a 21 HP engine and mower decks between 48 and 54 inches. While the horsepower is lower than other models, keep in mind that this is a powerful diesel engine. This mower is made with durable 10-gauge steel while the mower deck features a tough 5/16-inch U-frame platform. With the optional mulching kit, this mower breaks down grass clippings so that you don’t have to collect them—although a grass catcher is available, too. One of the things that sets this mower apart from others is the shaft drive PTO, which is a sturdy, low-maintenance improvement on belt-driven mower decks.

Kubota GR2020G

This mower offers several upgrades. It features a 5/16-inch U-frame platform that gives it enhanced durability. It also has a shaft-drive PTO to power the mower deck, which is a more durable, less maintenance intensive option compared to the belt drives that most riding mowers use. It’s a riding mower that has been designed for comfort with a high-backed seat, cruise control, and a step-through operator platform that makes it easier to get on and off the mower without bumping your shins.

With a 48-inch mower deck. and with Kubota’s Glide Steer technology, it features a tight turning radius that gives you professional results. Optional attachments include a front snow blade, snow blower and grass catcher.

Have questions about which is the best Kubota lawn tractor for you? Stop by our showroom or get in touch! We’ll be happy to help you pick the right fit.

The 6 Best Self-Propelled Lawn Mowers of 2023, Tested and Reviewed

Michelle Ullman is a home decor expert and product reviewer for home and garden products. She has been writing about home decor for over 10 years for publications like BobVila.com and Better Homes Gardens, among others.

Barbara Gillette is a Master Gardener, herbalist, beekeeper, and journalist. She has 30 years of experience propagating and growing fruits, vegetables, herbs, and ornamentals.

Emily Estep is a plant biologist and journalist who has worked for a variety of online news and media outlets, writing about and editing topics including environmental science and houseplants.

If you dream of a lush, green lawn, but dread the maintenance involved in keeping it that way, then a self-propelled lawn mower can make your life easier. These mowers not only power the blades but also power the wheels to make your pushing requirements little more than guiding the machine across the grass.

Brock Ingham, gardener, landscaper, and founder of the website Bigger Garden, says, The main advantage of a self-propelled mower is that it requires less effort to operate than a push mower. This can be beneficial for people with large lawns or those who have difficulty pushing a mower due to physical limitations. Self-propelled mowers can also provide a more consistent cut, since the speed is controlled by the mower rather than the operator. Overall, a self-propelled lawn mower can make mowing easier and more efficient.

Henry Bravo, founder and editor-in-chief of SmartGardenHome.com, adds, Self-propelled lawnmowers are much easier to maneuver around obstacles, and they can handle uneven terrain without a problem. Plus, I can adjust the speed so I can mow quickly or at a slower, more leisurely pace. And I love that I can easily switch between mulching, side discharge, and bagging capabilities.

We bought and tested several self-propelled mowers, both gas and electric, and evaluated many others based on their power, the size of lawn they can handle, their options for handling grass clippings, their range of cutting heights, the easiness of using the mower, and their overall value.

Best Overall

EGO Power Select Cut 56-Volt 21-Inch Self-Propelled Cordless Lawn Mower

• Variable-speed self-propel
• Generous battery runtime
• Fast recharging
• Folds for compact storage

Earning the top spot in our tests is a battery lawn mower that rivals the power of a gas mower but without the smelly fumes, the oil changes, or the frustrating pull cord. Instead, this self-propelled mower from EGO has a 56-volt, 7.5-Ah battery that provides up to 60 minutes of runtime on a single charge; that’s enough to mow most lawns up to a 0.5 acre and more than enough for our small yard. We put the mower to the test in early spring, mowing a lawn just out of winter dormancy that was patchy, wet, and ferny.

Other than attaching the bag, assembling the mower was easy. And a mere press of the button brought it roaring to life. This mower has a 21-inch cutting deck and a one-hand lever that adjusts the cutting heights through six different settings for grass heights of 1.5 to 4 inches. We found it very easy to adjust.

The lawn mower easily handles all common types of lawn grass, including tougher warm-season varieties like Bermudagrass, zoysia, and St. Augustine. A few buyers have complained that it struggles to lift overly tall grass high enough for an even cut. However, we found that it struggled a bit in the wet grass as well, becoming stuck at one point in a ferny patch. Aside from that, it delivers a precise and crisp cut that is sure to impress.

The speed of the mower is variable, so you can set it to match your stride from a leisurely 0.9 mph up to a brisk 3.1 mph. As this was our first time using a self-propelled mower, there was a bit of a learning curve. At first, it felt like the mower was pulling us along. However, we soon got the hang of it and appreciated the ease of adjusting the mower’s speed. We also liked the adjustable handle, which made it more comfortable to mow.

We found that the mower was easy to maneuver, even around obstacles or sharp turns. As the self-propelled function does most of the heavy work, this is also a great mower for yards with slopes. At nine inches in diameter, the mower’s wheels are fairly large, and it is rear-wheel drive, which also helps when mowing over rough terrain or hilly areas. You can dispose of the grass clippings in the included 2-bushel bag, discharge them to the side, or mulch them into fine clippings to quickly decompose them into healthful lawn nutrients. This mower even has a LED headlight, so you can mow early in the morning or at dusk to take advantage of mild temperatures.

Most of the mower’s construction is heavy-duty plastic for weather and rust resistance, but that might not be as durable as steel, although we felt it seemed quite sturdy. Once you finish mowing, the handle folds all the way down for easy storage. We really appreciated this feature, as the mower doesn’t take up as much room in the garage. This mower comes with a 56-volt battery and a fast charger that has the battery ready to go in just an hour.

How It Performed Long-Term

We are extremely satisfied with the performance of the lawn mower, particularly with how long the battery lasts. It can easily handle mowing the lawn three times without requiring a recharge. Even when it does need to be recharged, it only takes around 20 minutes. The mower is also highly effective when dealing with thick, tall grass and can even tackle 10 days of uncut grass without issue. Additionally, it can handle damp grass and leaves with ease. Initially, it took some time to become familiar with turning it on and utilizing the self-propel feature, but once we did, mowing the lawn became a breeze.

Price at time of publish: 549

Cutting Width: 21 inches | Power Source: Battery | Weight: 62.6 pounds | Grass Discard Options: Bag, mulch, side-discharge

The Best Self-Propelled Lawn Mowers in 2023 for Making Your Yard Work Easier

These lawn mowers drive themselves, taking the load off you in the process.

By Roy Berendsohn Published: Mar 21, 2023

One of the perks of the warm-weather season is getting to spend time outside. If you own your own home and have a yard, it’s very likely that in order to enjoy your outdoor space, you need to mow the lawn. The larger the yard, the more work it will be to maintain. If you have a lot of grass to cut, you’d be wise to consider a self-propelled lawn mower especially now that there are a ton of sales just in time for Memorial Day.

The primary difference between a standard push mower and a self-propelled mower is that the former moves when you push it, and the latter essentially moves itself with only your guidance. Once the engine is running, all you have to do is squeeze a handle or push a lever and the mower will start moving forward with you as you walk.

Turning the mower around is your job, but once you have your heading, just keep the drive handle squeezed and escort the mower down the path, no pushing necessary.

Self-propelled law mowers take power off the engine and route it via a belt to a pulley on the transmission and axle. When you move the drive control lever on the mower handle, you tension the belt, causing the pulley to turn, and this drives the transmission, moving the mower forward.

Move the drive control lever back and the tension is released, the pulley stops turning, and the mower stops moving forward. The belt-driven transmission is a time-tested design to power the mower and take the load off you in the process.

What to Consider

A mower is like many consumer products in that the more features a manufacturer adds, the more expensive it becomes. But a longer or more eye-catching list of features isn’t necessarily better. Sometimes less is more. Here are the most important to keep in mind.

Front-wheel drive mowers tend to be less expensive than rear-wheel drive units. They can be easier to turn because you don’t have to disengage the drive wheels to do so. Simply push down on the handlebar to raise the front wheels off the ground. However, their traction isn’t as strong on hills or when the bag is full, as there isn’t as much weight over the drive wheels.

Rear-wheel drive mowers do cost more and aren’t as easy to turn, as you do need to disengage the drive—but this isn’t too much of a hassle. Rear-wheel drive mowers shine on hills and inclines, and when the grass bag is full. In either scenario, weight is shifted rearward and over the drive wheels, which enables superior traction, thus making the self-propel more effective.

An engine as small as 125 cc can power a mower, but most are somewhere in the 140 cc to 190 cc range. A large engine helps when powering through tall, lush grass or in extreme conditions, such as with a side discharge chute in place and mowing tall weeds in a border area. Also, the extra torque provided by a larger engine can improve bagging when the going gets tough (tall, leaf-covered grass in the fall). But if you mow sensibly and pay attention to deck height—and especially if you don’t let your lawn get out of control—an engine between 140 and 160 cc has more than enough power to get the job done.

A mower can have all four wheels the same diameter (7 to 8 inches), or it may have rear wheels that range from 9.5 inches to 12 inches in diameter. Larger rear wheels help the mower roll more easily over bumpy ground.

With some mowers you can start the engine with the twist of a key or the press of a button. It’s a great option, but a luxury. Keep the mower engine tuned and use fresh fuel with stabilizer added to it, and you’ll never have trouble starting.

Any number of mechanisms can control a mower’s ground speed—a squeeze handle, a drive bar that you press forward, even a dial. There’s no single right answer here. Look at the design and think about how you like to work. For example, if more than one person will be using the mower (and not all of them are right-handed), a drive control like that on a Toro Personal Pace mower might be the answer. Just push down on the bar to make it go faster. Let up on the bar to slow down.

A mower that can bag, mulch, and side discharge is known as a three-function mower, the most versatile kind. Two-function mowers bag and mulch or mulch and side discharge.

Mowers will typically have one, two, or four levers to control the deck height. Single-lever adjustment is the easiest to use, but it requires more linkage, which adds weight and complexity. If, for some reason, you find yourself varying deck height frequently, it’s a good option. Otherwise, two or four levers work just fine.

Only Honda makes a gas-engine mower with a high-impact plastic deck (there are battery mowers that have plastic decks). Otherwise, mowers generally have a steel deck, and a few manufacturers—Toro, for one—offer a corrosion-resistant aluminum deck. An aluminum deck won’t rot the way a steel deck will, but you still need to keep it clean.

This is a hose fitting mounted on top of the mower’s deck. When you’re done mowing, hook up a hose and run the mower to power wash the underside of the deck. We’ve had mixed results with these, but they’re better than just letting a mass of dried grass clippings accumulate.

expensive mowers come with a more durable bag with more dust-blocking capability. If you bag a lot, especially leaves or other lawn debris in the fall, then you need a mower with a higher quality dust-blocking bag. Having said that, if you rarely bag, the standard one that comes with a mower will last you the life of the mower.

Also called wide-area mowers, machines in this subgroup help homeowners better reconcile their need for more power and speed with the fact that they may not have enough storage for a tractor or zero-turn mower. A typical residential walk mower has a single-blade deck that cuts a swath from 20 to 22 inches wide. Wide-cut mowers (built for homeowner use) have either a single blade or, more typically, a pair of blades, cutting from 26 to 30 inches with each pass. Some of these are rated for light commercial use and have larger decks, in the 32-inch range, and engines that start at 223 cc and go up to about 337 cc.

Wide-cut mowers typically employ gear or hydrostatic drive transmissions, and they have top speeds of about 4 to 6 miles per hour. At their fastest, they move so quickly you have to trot to keep up with them. Needless to say, they’re overkill for small yards; only opt for one of these if you’ve got a significant plot of land that you need to keep tidy, but not one so large that you’d be better off going with a full-on riding mower.

How We Tested and Selected

We compiled this list based on Popular Mechanics mower testing and our knowledge of the lawn mower market at large. For our testing, we put mowers through the paces using our standard Popular Mechanics methodology: We cut turf grasses such as fescues and blue grass and rougher non-turf grasses like Timothy, clover, orchard grass, and wild oats, all in both normal and shin-deep heights. We mow uphill, downhill, and across the faces of hills. The maximum slope we cut is about 30 degrees.

That may not sound like much, but it’s about all you can do to stand on it, let alone push a mower up it or across it. We mow damp and wet grass to test general cutting performance and whether clippings accumulate on the tires. And we cut dry and dusty surfaces to see how well the bag filters under less-than-optimal conditions.

Honda HRN 216VKA

Key Specs

Honda mowers enjoy a sterling reputation. Having tested their walk and self-propelled mowers for the last 30 years, we feel confident that Honda’s entry level mower is a great choice for homeowners looking for power and durability. The HRN features a GCV 170 gas engine that’s built to withstand long hours of operation.

If you do your own maintenance (and most owners who buy this class of product do), you’ll appreciate the easily accessible spark plug and the fuel shutoff valve that enables better winter storage. Close the fuel shutoff and run the mower until it sputters to a halt. This will clear the carburetor of any gasoline, which will prevent the ethanol in it from disintegrating and causing running issues later on. Open the shutoff valve in the spring, add some fresh gasoline, and the mower should start easily.

All this maintenance stuff is great, but we can also tell you that our past test findings on other Hondas prove that their cut quality is outstanding for cleanliness. Sharp blades deliver a velvet-like finish. And their bagging ability is also quite good, in the same league with other well-bagging mowers from Toro.

In all, if you take mowing seriously, you should enjoy this Honda. If you have a little wiggle room in your budget, consider the Honda HRX, which features a mower powerful engine and a composite deck that won’t rust and is renowned for its durability.

One note is that Honda has announced that it will cease selling lawn mowers in the United States after this year—so if you’re considering buying one, best do it sooner rather than later.

Toro Recycler 60-Volt Max Lithium-Ion

Key Specs

Toro mowers have garnered more recommendations from us than any other brand for two reasons: build quality and cut quality. These were amply demonstrated in our testing as the Recycler turned in the best ratio of cut area per amp-hour of battery in the self-propelled category, while at the same time not skimping on cutting, mulching, or bagging quality.

We attribute this outstanding mower performance to three features, all upgrades to the previous version of this machine. First, the air vent at the front of the mower deck seems to improve mulching and bagging performance. Toro calls it Vortex technology, a design that increases air flow under the deck. This helps to stand the grass for a cleaner cut, which improves mulching performance, and also allows better airflow into the bag when collecting the clippings.

Next, the company’s redesigned “Atomic” blade configuration appears to assist the air flow and clipping movement. Finally, the three-phase, 60-volt motor is exceptionally efficient, resulting in a large cut area for a single battery.

Toro has maintained features that make this mower work: rear wheel drive, a one-piece deck that’s all steel (no plastic nose), 11-inch wheels to help it roll over roots and crevices, and the same fold-forward handle that was an industry breakthrough when it was introduced some years ago.

Ryobi 40-Volt Brushless Self-Propelled Mower

Key Specs

This is one of Ryobi’s top-of-the-line mowers, and it’s American-made construction is something we wish we saw more of. It delivers a tremendous cut area with its two 6-Ah batteries providing a total of 12-Ah of capacity, and its X-shaped blade leaves a pristine surface in its wake.

Ryobi estimates the design should provide 70 minutes of run time; we didn’t time our cut, but it strikes as plausible. Its rear-wheel drive and reasonably aggressive tire tread pattern provide good hill climbing and sidehill cutting performance, and its bagging on all surfaces (level, sidehill, and uphill) is also commendable.

Other ease-of-use features include an easily installed or removed bag that mounts and dismounts straight up and down through the handle; deck adjustment is quick and easy thanks to a single-level deck height adjustment. The straight edge deck is polypropylene; it will never rust and needs very little care other than basic cleaning.

Toro TimeMaster 30 in. Briggs Stratton Personal Pace

The Toro Timemaster 30-in. mower has been around for several years and has earned a reputation as a sturdy workhorse for homeowners who want to cut down on their mowing time. It’s also used by some professionals as well. A few years ago the Timemaster got a slightly more powerful Briggs and Stratton gas engine, so it should have no issues powering through most demanding mowing jobs.

The Timemaster is rear-wheel drive and features Toro’s Personal Pace drive system that’s used on many of its self-propelled mowers. This allows the mower to move at your speed by simply pushing down or releasing the handle, which is spring-tensioned.

With a 30-in. deck, Toro claims the Timemaster will help you reduce your mowing time by about 40% compared to using a standard-sized mower. You can mulch, back, or side discharge with the Timemaster, and the handlebar can be locked in a fully vertical position to reduce space consumption in storage.

If you have half an acre to a full acre of lawn to mow and prefer the experience of a walk-behind mower versus a tractor or zero-turn, the Timemaster is worth a look.

Craftsman M220

Key Specs

Craftsman mowers have been doing very well in our tests, so we can recommend this one because it’s so much like the many other of the brand’s models that we’ve tested. If you’re looking for a good blend of maneuverability and power, you’ll get it with this mower. Its front drive helps move it along and makes it easy to turn.

It’s important to note that front-drive mowers do lose some traction when running uphill, particularly with a full grass bag. But if your slope is less than 20 degrees, and you’re not bagging uphill, you’ll be fine. The side discharge will also help you handle tall grass. Adjust the two deck levers to bring the mower up to full height and have at the rough stuff.

The fact that this mower bags, mulches, and side discharges is a plus, enabling you to handle a wide range of mowing conditions, from early spring and late into the fall. Three-function mowers like this are our preference for that versatility.

Toro Super Recycler Self-Propelled Lawn Mower

Key Specs

This is a beauty of a mower, with a cast-aluminum deck and a smooth-running Briggs Stratton 163-cc engine. We tested the Honda engine-equipped version, and it was effective at both bagging and mulching, even in moist grass.

Equipped with rear-wheel drive and the Personal Pace system (the farther you push the drive bar, the faster the mower goes), it’s an effective hill climber and moderately effective on sidehill cutting. It has relatively small 7.5-inch tires on all four corners, which causes this Toro to bump up and down a bit on washboard surfaces. But the good news is that it’s equipped with a far higher quality tire than we’re used to seeing these days. We didn’t notice them pick up any grass on moist surfaces.

Other features we like include its forward-fold handle that has a built-in shock absorber that Toro calls a Flex Handle Suspension, and a high-quality grass bag that loads through the handle, from the top.

QA

Are there special maintenance considerations with self-propelled mowers?

Yes. Both front- and rear-wheel drive mowers typically feature a drive belt, which can crack or wear out over time. Fortunately these belts are not difficult or particularly expensive to replace.

Secondly, you may have to replace the drive wheels occasionally. These wheels are driven with gears. there are typically teeth on the inside diameter of the drive wheel that line up with a gear on the axle. These teeth can wear out, especially if they are made of plastic. Higher-end mowers may feature drive wheels with a metal gear that meets the metal axle gear, which improves longevity of these components.

My lawnmower says I don’t ever have to change the oil, but just add oil when needed. Is this OK?

It’s not a good idea to never change the oil in your lawn mower. In a lawn mower, same as a car, oil degrades over time and is less effective at reducing heat and friction in metal components. Changing the oil in your lawn mower is easy to do and will significantly increase its service life. For most homeowners, changing the oil at the beginning or end of each mowing season should be sufficient, though there is certainly no harm in doing it more often.

Roy Berendsohn has worked for more than 25 years at Popular Mechanics, where he has written on carpentry, masonry, painting, plumbing, electrical, woodworking, blacksmithing, welding, lawn care, chainsaw use, and outdoor power equipment. When he’s not working on his own house, he volunteers with Sovereign Grace Church doing home repair for families in rural, suburban and urban locations throughout central and southern New Jersey.