Patent ID: 12232451

DETAILED DESCRIPTION

FIG.1schematically illustrates an example integrated transaxle standing lawnmower or mower20. As will be described hereafter, mower20is configured to support an operator platform at least partially below both integrated transaxles, allowing an operator to assume a more ergonomic position and achieve enhanced weight distribution.

As schematically shown byFIG.1, mower20comprises frame22, left and right front wheels24L and24R (collectively referred to as wheels24), left and right drive wheels26L,26R (collectively referred to as wheels26), cutting deck assembly28, prime mover32, left side and right side integrated transaxles36L,36R (collectively referred to as integrated transaxles36) and operator platform40. Frame22comprises a platform or framework40supported by wheels24,26above ground or terrain. Frame22supports the remaining components of mower20.

Wheels24extend from a forward end of mower20. In the example illustrated, wheels24are passive, not driven under power. In one implementation, wheels24comprise caster wheels, being able to swivel with respect to frame22about a vertical axes to accommodate turning and rotating of mower20. In yet other implementations, wheels24are not passive, but are actively controlled or steered by an operator.

Wheels26are located at a rear of mower20. In the example illustrated, wheels26are rotatable about a single horizontal rotational axis39. Wheels26are driven under power by integrated transaxles36. In one implementation, wheels26have a diameter of at least 20 inches and nominally at least 23 inches. As will be described hereafter, this larger diameter of wheels26facilitates supporting of integrated transaxles36at a height which provides sufficient clearance for extending operator platform40below integrated transaxles36. In other implementations, wheels26have other dimensions.

Cutting deck assembly28severs or cuts grass and other vegetation under power provided by prime mover32. Cutting deck assembly28comprises cutting or mower deck42and at least one cutting blade44mounted undercutting deck42and rotatable under influence of prime mover32. In one implementation, each cutting blade44receives power by a belt and pulley arrangement operably coupling such cutting blades44to prime mover32. Although mower20is illustrated as comprising three cutting blades44and although cutting deck28is illustrated as having the illustrated shape encompassing or covering each of the three cutting blades44, in other implementations, mower20has a single cutting blade44, a pair of cutting blades44or more than three cutting blades44. In other implementations, the layout of cutting blades44may be different from that illustrated. In other implementations, mower deck42may have other shapes.

Prime mover32comprises a device which produces torque to drive cutting blades44and integrated transaxles36. In one implementation, prime mover32comprises an internal combustion engine supported by frame22and operably coupled to the pumps of integrated transaxles36. In yet another implementation, prime mover32comprises an electrically powered device, such as electrically powered motor, operably coupled to the pumps of integrated transaxles36.

For purposes of this disclosure, the term “coupled” shall mean the joining of two members directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two members or the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members or the two members and any additional intermediate member being attached to one another. Such joining may be permanent in nature or alternatively may be removable or releasable in nature. The term “operably coupled” shall mean that two members are directly or indirectly joined such that motion may be transmitted from one member to the other member directly or via intermediate members.

Integrated transaxles36transmit torque from prime mover32to drive wheels26. Integrated transaxles36facilitate independent powering or driving of drive wheels26. In particular, each integrated transaxle36is capable of being rotated under power in forward and reverse directions independent of the other integrated transaxles36to facilitate forward, reverse and turning of mower20. In the example illustrated, such wheels26may be independently driven of one another to provide “zero turn” capabilities for mower20. Each integrated transaxle36comprises a hydraulic pump48and a hydraulic motor50, each of which are contained within a single housing52. Hydraulic pump48is operably coupled to prime mover32so as be driven by prime mover32. Hydraulic pump48supplies hydraulic fluid under pressure to hydraulic motor50to drive hydraulic motor50. The drive motor50is operably coupled to the associated wheel26to drive the associated wheel26.

Operator platform40is located at a rear of mower20to support a standing operator of mower20. In the example illustrated, platform40comprises a plate or panel at the rear of mower20. Platform40extends at least partially beneath housing52of each of integrated transaxles36L and36R. As shown byFIG.2, operator platform40has a front end54having a rim, lip or foot stop56. In the example illustrated, foot stop56is located forward of rotational axis39directly beneath housing52of integrated transaxle36L. In a similar fashion, foot stop56is also directly beneath housing52of integrated transaxle36R as shown inFIG.1. Those portions of operator platform40extending rearward of foot stop56are sufficiently spaced below lowermost surfaces of housing52such that the operator may position his or her feet upon platform40with his or her feet extending to foot stop56(the proportion of the feet contacting foot stop56) without the top surfaces of the feet contacting housing52of either of integrated transaxles36. In one implementation, operator platform40has an upper surface58directly underlying lower surface of housing52of transaxle36L. In one implementation, the upper surface58is spaced from the lower surface of housing52by a spacing S of at least 2 inches.

Because operator platform40extends directly beneath, below and under housing52of integrated transaxles36, platform40supports the operator at a position closer to axis39and closer to a center of mass of mower20, which is at or forward axis39. As a result, platform40provides greater stability. Because operator platform40extends directly beneath, below an outer housing52of integrated transaxles36, operator platform40has a wider width. In the example illustrated, platform40extends directly beneath housing52across the majority of the transverse width W of each of housings52of integrated transaxles36. In the example illustrated, platform40extends directly beneath housing52across substantially all of the transverse width W of each of housing52of integrated transaxles36. As a result, platform40accommodates wider stances of an operator for further stability. In addition, platform40provides a wider transverse surface along which the operator may selectively position his or her feet to shift his or her weight, such as when mower20is tilted, such as when operating on a side of a hill.

As further shown byFIG.2, in the example illustrated, platform40is supported such that upper surface58of platform40is inclined, sloping upward as upper surface58extends rearward of axis39. As a result, upper surface58of platform40supports the operator in an orientation or at an angle in which the operator leans forward. Because platform40supports an operator at an inclination, the operator center mass or gravity is more in alignment with or closer to the center of mass of mower20. As a result, platform40more stably supports the operator such that the operator avoids having the sensation that he or she is “hanging on” as a mower is driven forward. In the example illustrated, platform40, when supporting an operator, is inclined (rearwardly extending upwardly) at an angle A relative to a horizontal plane. In one implementation, angle A is at least 10 degrees and nominally at least 15 degrees above the horizontal. For purposes of this disclosure, recited angles of any operator platform, such as platform40or platform340, are in reference to the angle of the platform relative to horizontal when the mower itself is horizontal, i.e., when the mower is resting upon a level supporting surface and the tires are inflated such that the overall frame of the mower is supported in and extends in a horizontal plane.

FIGS.3and4illustrate mower120, an example implementation of mower20. Mower120is similar mower20except that mower120additionally comprises platform suspension system124, suspension adjuster126, position sensor130and parking brake and blade drive engager134. Those remaining elements of mower120which correspond to corresponding elements of mower20are numbered similarly.

Suspension system124(schematically shown inFIG.4) resiliently supports platform44movement as mower20encounters bumps and the like to reduce shock and vibration upon the operator. In the example illustrated, platform40is pivotally supported about a pivot axis138proximate the forward end54of platform40. In the example illustrated, platform40pivots between a fully raised position142(shown in broken lines) and a lowered position144. Platform40is resiliently supported at the raised position142in the absence of an operator upon platform40. Platform40is resiliently supported at the lowered position in the presence of an operator, wherein the way to the operator pivots platform42the lowered position. Pivot axis138transversely extends directly beneath housing52of each of transaxles36. In the example illustrated, pivot axis138extends directly beneath or forward drive axis39.

In one implementation, suspension system124comprises tension springs suspending platform40from portions of frame22about platform40. Such tension spring support platform40in the fully raised position in the absence of an operator. In another implementation, suspension system124comprises compression springs captured between platform40and portions of frame22below platform40. Such compression springs support platform40in the fully raised position142in the absence of an operator upon platform40. In yet other implementations, suspension system124comprises a combination of tension springs and compression springs.

Suspension adjuster126comprises a mechanism or device that adjusts the spring or springs resiliently supporting platform40so as to adjust the resistance against movement from the raised position142toward the lowered position144provided by such spring or springs. In one implementation, suspension adjuster126comprises a first threaded member connected to an end of a tension spring and wherein the threaded member is rotatable with respect to a second threaded member secured to frame22, wherein relative rotation of the two threaded members adjusts the position of the tension spring to adjust the amount of resistance applied by the tension spring against resilient movement of platform40from the fully raised position142toward the lowered position144. For example, in one implementation, each tension spring supporting platform40has an end secured to an eye bolt, wherein the eye bolt is secured to platform22by a nut or internally threaded member such that rotation of the nut or rotation the eye bolt moves the positioning of the end of the tension spring to adjust the supported height of platform40in the absence of an operator and the resistance provided by the tension spring. In other implementations, suspension adjuster126may have other configurations.

Position sensor130(schematically shown) comprises a sensor that senses or detects positioning of operator platform40. In one implementation, position sensor130outputs electrical signals which are transmitted to electronic circuitry of parking brake and blade drive engager134. In one implementation, position sensor130comprises a contact switch which detects when operator platform40has resiliently pivoted to a predefined raised position144, presumably in the absence of an operator. In yet another implementation, position sensor130comprises a potentiometer operably coupled to platform40so to output different electrical signals based upon which position, of a plurality of available positions, that operator platform40presently resides. In yet other implementations, position sensor130may comprise other types of sensing device that output electrical signal indicating the position of operator platform40.

In yet another implementation, position sensor130comprises a mechanical linkage operably connecting operator platform40to transmit a mechanical force to parking brake and blade engager134. For example, in one implementation, position sensor130comprises a Bowden cable having a first end operably coupled to platform40and a second and connected to parking brake and blade drive engager134. In such an implementation, movement of platform40pushes or pulls upon the Bowden cable such that an operational state of parking brake and blade drive engager134is adjusted or changed.

Parking brake and blade drive engager134utilizes signals or mechanical force received from position sensor130to engage or disengage a single or pair of parking brakes150and one of more blade drives152(shown inFIG.3). Parking brakes150retain or resist motion of wheels26. When engaged, blade drive152transmits torque from prime mover32to blades44to rotate blades44. When disengaged, blade drive152disconnects blades44from prime mover32to inhibit the driving of blades44. In one implementation, blade drive152comprises a clutch or other selectable transmission component.

Engager134comprises a controller, such as the control board or electronic circuitry, that, based upon the positioning of operator platform40, engages or disengages parking brake150and blade drive152. In response to operator platform40moving or pivoting to the fully raised position, indicating the absence of an operator, engager134automatically engages parking brake150and automatically disengages blade drive152. At the same time, prime mover32continues to operate or run, avoiding the need of having to be restarted to resume use of mower120. In one implementation, in response to the positioning of operator platform40moving or pivoting to the lowered position from the fully raised position, engager134automatically disengages parking brake150and automatically engages blade drive152, allowing immediate resumption of the use of mower120once the operator remount platform40. In yet another implementation, once the operator has the mounted platform40resulting in parking brake150being engaged in blade drive152being disengaged, remounting of platform40by the operator does not automatically disengage parking brake150and/or automatically reengage blade drive152. In such an implementation, additional confirming action or input from the operator is required to disengage parking brake150and/or reengage blade drive152.

FIG.5is a flow diagram of an example method200for the operation of mower120. As indicated by block202, the position of platform40is sensed. As indicated by block204, based on the sensed position of platform40, engager134automatically engages or disengages each of the parking brake150and blade drive152. As noted above, in one implementation, the parking brake150is automatically engaged or the blade drive152is automatically disengaged in response to platform40pivoting or moving to the fully raised position, wherein the movement of platform40is sensed and/or the final position of platform40in the fully raised position is sensed.

FIGS.6-17illustrate mower320, an example implementation of mower120. As shown byFIGS.6and7, mower320comprises frame322, left and right front wheels324L and324R (collectively referred to as wheels324), left and right drive wheels326L,326R (collectively referred to as wheels326), cutting deck assembly328, prime mover332, left side and right side integrated transaxles336L,336R (collectively referred to as integrated transaxles336), control tower338and operator platform340. Frame22comprises a platform or framework supported by wheels324,326above ground or terrain327. Frame322supports the remaining components of mower320.

Wheels324extend at a forward end of mower320. In the example illustrated, wheels324are passive, not driven under power. In one implementation, wheels324comprise caster wheels, being able to swivel with respect to frame322about vertical axes to accommodate turning and rotating of mower320. In yet other implementations, wheels324are not passive, but are actively controlled or steered by an operator.

Wheels326are located at a rear of mower320. In the example illustrated, wheels326rotatable about a single horizontal rotational axis339. Wheels326are driven under power by integrated transaxles336. In one implementation, wheels326have a diameter of at least 20 inches and nominally at least 23 inches. As will be described hereafter, this larger diameter of wheels326facilitates supporting of integrated transaxles336at a height which provides sufficient clearance for extending operator platform340at least partially below integrated transaxles336. In other implementations, wheels326have other dimensions.

Cutting deck assembly328severs or cuts grass and other vegetation under power provided by prime mover332. Cutting deck assembly328comprises cutting or mower deck342and at least one cutting blade344(one of which is shown inFIG.16) mounted under cutting deck342and rotatable under influence of prime mover332. In the illustrated example, each cutting blade344receives power by a belt and pulley arrangement347operably coupling such cutting blades44to prime mover332. Although mower320is illustrated as comprising three cutting blades344and although mower deck342is illustrated as having the illustrated shape encompassing or covering each of the three cutting blades344, in other implementations, mower320has a single cutting blade344, a pair of cutting blades344or more than three cutting blades344. In other implementations, the layout of cutting blades344may be different from that illustrated. In other implementations, mower deck342may have other shapes.

Prime mover332comprises a device which produces torque to drive cutting blades344and integrated transaxles336. In the example illustrated, prime mover332comprises an internal combustion engine supported by frame322and operably coupled to the pumps of integrated transaxles336. Prime mover332receives fuel from fuel tank349. In yet another implementation, prime mover332comprises an electrically powered device, such as electrically powered motor operably coupled to the pumps of integrated transaxles336.

Integrated transaxles336are driven under the influence of prime mover332to drive wheels326. For purposes of this disclosure, an “integrated transaxle” refers to a pump, a motor and a hydraulic system contained within a single housing or multiple housings joined adjacent to one another, wherein the housing or housings enclose a pump input shaft and a motor output shaft extending through the housing or housings such that the integrated transaxle is a modular, self-contained and independent unit. Integrated transaxles336facilitate independent powering or driving of drive wheels326. In particular, each integrated transaxle336is capable of being rotated under power in forward and reverse directions independent of the other integrated transaxle336to facilitate forward, reverse and turning of mower320. In the example illustrated, such wheels326may be independently driven of one another in opposite directions to provide “zero turn” capabilities for mower320.

As illustrated inFIGS.10and11, each integrated transaxle336comprises a hydraulic pump348and a hydraulic motor350, each of which are contained within a single housing352. Hydraulic pump348is operably coupled to prime mover332so as be driven by prime mover332. Hydraulic pump348supplies hydraulic fluid under pressure to hydraulic motor350to drive hydraulic motor350. In one implementation, hydraulic pump348includes a swash plate (not shown) that is movable to cause hydraulic fluid to flow in forward or reverse directions through drive motor350. The drive motor350is operably coupled to the associated wheel326to drive the associated wheel326. In the example illustrated, integrated transaxles336are self-contained and do not mix hydraulic fluid or share a reservoir.

Control tower338rises vertically from frame322rearward of prime mover332. Control tower338comprises operator support360manual controls362and drive transmission364. Operator support360comprises a panel, such as a cushion, forwardly inclined above operator platform40. Operator support360provides a surface against which an operator, when standing upon platform340, may rest and lean against.

Manual controls362comprise levers, buttons or other input devices by which an operator controls the operation of mower320. A portion of manual controls362are operably coupled to drive transmission364through linkages, cables and the like. Actuation of manual controls362adjusts the state of drive transmission364to selectively vary independent driving of wheels326by integrated transaxles336. For example, actuation manual controls362controls the rate at which hydraulic fluid is supplied by pump348to the associated motor350and the direction, through adjustment of the swash plate, that the hydraulic fluid drives motor350to control the speed and rotational direction at which wheels326are independently driven.

Operator platform340is located at a rear of mower320to support a standing operator of mower320. In the example illustrated, platform340comprises a plate or panel at the rear of mower320. As shown inFIG.11, platform340extends beneath housing352of each of integrated transaxles336L and336R.

For purposes of this disclosure, the term “front” and variations thereon shall mean positioned further in the forward direction and an element being compared. The term “reverse” and variations thereon shall mean in a direction parallel to the direction from the front wheels24,324toward the rear wheels26,326. The term “rear” and variations thereon shall mean position further in the reverse direction than an element being compared. The terms “right,” “left,” and variations thereon shall be in reference to the respective right left is viewed by forward-looking operator. The terms “up,” “down” and variations thereof to be used as from the perspective of an operator standing on the operator platform40,340. The terms “above” and “over” shall mean intersecting a comparatively higher horizontal plane. The terms “directly above” and “directly over” shall mean intersecting a comparatively higher horizontal plane and intersecting a common vertical line. The terms “below” and “under” shall mean intersecting a comparatively lower horizontal plane. The terms “directly below”, “directly under” and “directly beneath” shall mean intersecting a comparatively lower horizontal plane and intersecting a common vertical line. Elements that are “directly above” or “directly below” other elements are also “above” or “below” the other elements, but the opposite is not necessarily true.

As shown byFIG.7, operator platform340has a front end354having a rim, lip or foot stop356. In the example illustrated, foot stop356is located forward of rotational axis339directly beneath housing352of integrated transaxle336L. In a similar fashion, foot stop356is also substantially directly beneath housing352of integrated transaxle336R. Those portions of operator platform340extending rearward of foot stop356are sufficiently spaced below lowermost surfaces of housing352such that the operator may position his or her feet upon platform340with his or her feet extending to foot stop356(the toe or shoe tip portions of the feet contacting foot stop356) without the top surfaces of the feet contacting housing352of either of integrated transaxles336. In other implementations, a pad or cushion layer is mounted below the bottom surface of integrated transaxles336, wherein the top of the operator's feet contact the cushion layer or layers, but are spaced from the bottom surface of housing352of each of the integrated transaxles336. As shown byFIG.14, operator platform340has an upper surface358directly underlying lower surface of housing352of transaxle336L. In one implementation, the upper surface358adjacent foot stop356is spaced from the lower surface of housing352by a spacing of at least 6 inches.

As shown byFIGS.12-15, because operator platform340extends directly beneath, below and under housing352of integrated transaxles336, platform340supports the operator at a position closer to axis339and closer to a center of mass of mower320, which is at or forward axis339. As a result, platform340provides greater stability. Because operator platform340extends directly beneath, below an outer surface of housing352of integrated transaxles336, operator platform340has a wider width. As shown byFIG.13and as shown byFIG.17which transparently illustrates platform340from a bottom of mower320, platform340extends directly beneath housing352across the majority of the transverse width W of each of housings352of integrated transaxles336. In the example illustrated, platform340extends directly beneath housing352across substantially all of the transverse width W of each of housing352of integrated transaxles336. As a result, platform340accommodates wider stances of an operator for further stability. In addition, platform340provides a wider transverse surface along which the operator may selectively position his or her feet to shift his or her weight, such as when mower320is tilted, such as when operating on a side of a hill.

In one implementation, wherein mower320has a wheel track, the distance between the transverse center of the left drive wheel26L to the transverse center of the right drive wheel26R, platform340has a transverse width of at least 55% of the wheel track and nominally at least 60% of the wheel track. For example, in one implementation, mower320comprises a 52 inch cutting swath mower having a wheel track of 34.8 inches and a platform340having a transverse width of 21 inches. In yet another implementation, mower320comprises a 62 inch cutting swath mower having a wheel track of 43 inches and a platform having a transverse width of at least 24 inches.

As further shown byFIGS.14and15, in the example illustrated, platform340is supported such that upper surface358of platform340is inclined, sloping upward as upper surface358extends rearward of axis339. As a result, upper surface358of platform340supports the operator in an orientation or at an angle in which the operator leans forward. Because platform340supports an operator at an inclination, the operator center mass or gravity is more in alignment with or closer to the center of mass of mower320. As a result, platform340more stably supports the operator such that the operator does not have the sensation that he or she is “hanging on” as a mower is driven forward. In the example illustrated, platform340, when supporting an operator, is inclined at an angle A relative to a horizontal plane. In one implementation, angle A is at least 10 degrees and nominally at least 15 degrees above the horizontal.

Although platform340is illustrated as a single continuous platform that accommodates both feet of an operator, in other implementations, platform340alternatively comprises a pair of spaced footpads, a left foot pad for the left foot of the operator and a right foot pad for the right foot of the operator. Although operator platform340is illustrated as comprising foot stop356, in other implementations, foot stop356is omitted. Although platform340is illustrated as having a substantially planar or flat upper surface358, in other implementations, platform340comprises ridges, dimples, ribbing or other surface structures having high levels of friction for being gripped by the feet of the operator. Although operator platform340is illustrated as being inclined or tilted to support the operator in a leaning forward orientation, in other implementations, operator platform340alternatively extends in a horizontal plane or is inclined in the rearward direction at other angles.

As shown byFIGS.13and16-17, mower120additionally comprises platform suspension system324, suspension adjuster327, position sensor330and parking brake and blade drive engager134. Suspension system324resiliently supports platform44movement as mower20encounters bumps and the like to reduce shock and vibration upon the operator. In the example illustrated, platform340is pivotally supported about a pivot axis341proximate the forward end354of platform340. In the example illustrated, platform340pivots between a fully raised position and a lowered position. Platform340is resiliently supported at the raised position in the absence of an operator upon platform340. Platform340is resiliently supported at the lowered position in the presence of an operator, wherein the way to the operator pivots platform340to the lowered position. As shown byFIG.17which transparently illustrates portions of mower320, pivot axis341transversely extends directly beneath housing352of each of transaxles336. In the example illustrated, pivot axis341extends just rearward (within 2 inches) of forward drive axis39.

As shown byFIG.13, suspension system124comprises resilient suspenders370, support panel372and resilient supports374. Resilient suspenders370suspend platform40from portions of frame22about platform340. Such resilient suspenders support platform340in the fully raised position in the absence of an operator. In the example illustrated, resilient suspenders370comprise tension springs. In other implementations, resilient suspenders370alternatively comprise resiliently stretchable or elastomeric straps, bands or cables.

Support panel372comprises a panel support by frame22below platform340. Support panel372contacts or abuts a lower surface of platform340when platform340has completely “bottomed out”. Support panel372further supports resilient supports374. In the example illustrated, resilient supports374comprise compression springs. In other implementations, resilient supports374comprise rubber, rubber-like or elastomeric resilient bumpers that resiliently bend or resiliently compress in response to receiving a load from platform340. As shown byFIG.17which transparently illustrates support panel372, resilient supports374are captured between support panel372and an underside of platform340.

In another implementation, platform340is a resiliently supported in a raised inclined orientation by torsion spring having a first end portion secured to platform340and a second end portion secured to the rest of the mower, such as support panel372. Pivotal movement of platform340about its pivot axis, in response to receiving a load upon platform340, moves platform340against a torsional bias provided by the torsion spring.

Suspension adjuster327comprises a mechanism or device that adjusts the suspenders and supports resiliently supporting platform340so as to adjust the resistance against movement from the raised position toward the lowered position provided by such supports374. In the example illustrated, suspension adjuster327comprises a series of mounting locations376, each mounting location376being differently spaced with respect to pivot axis341of platform340. Suspension adjuster306allows the positioning of supports374to be mounted at a selected one of the different mounting locations376to vary a lever arm between pivot axis341and the supports374so as to adjust the resistance provided by supports374.

In the example illustrated, each mounting location376comprises an aperture extending through support platform372. Each aperture is sized to receive a bolt having a head which captures a washer against the lowest coil of the associated compression spring serving as support374. A nut (not shown) retains the bolt in place in the selected aperture at the selected mounting location376. In other implementations, each mounting location376may comprise other retention mechanisms or devices for releasably retaining or securing each of supports374at a selected one of the mounting locations376.

In other implementations, suspension adjuster126may have other configurations. For example, in implementations in which supports374additionally or alternatively comprise a torsion spring, suspension adjuster126additionally or alternatively comprises one or more different locations for mounting the first end portion or the second end portion of the torsion spring to adjust the degree or extent of torsional resistance that the spring provides against rotation of platform340about its pivot axis. In one implementation, portions of the frame of the mower, such as platform support372, include a series of apertures, wherein an end portion of the torsion spring may be selectively mounted or secured within one of the apertures to vary a degree of torsional resistance provided by torsion spring374against pivotal movement of platform340.

As described above, position sensor130(schematically shown) comprises a sensor that senses or detects positioning of operator platform340. In one implementation, position sensor130output electrical signals which are transmitted to electronic circuitry of parking brake and blade drive engager134. In one implementation, position sensor130comprises a contact switch which detects when operator platform340has resiliently pivoted to a predefined lowered position, presumably in the presence of an operator. In yet another implementation, position sensor130comprises a potentiometer operably coupled to platform340so to output different electrical signals based upon which position, of a plurality of available positions, that operator platform340presently resides. In yet other implementations, position sensor130may comprise other types of sensing device that output electrical signal indicating the position of operator platform340.

In yet another implementation, position sensor130comprises a mechanical linkage operably connecting operator platform340to transmit a mechanical force to parking brake and blade engager134. For example, in one implementation, position sensor130comprises a Bowden cable having a first end operably coupled to platform340and a second and connected to parking brake and blade drive engager134. In such an implementation, movement of platform340pushes or pulls upon the Bowden cable such that an operational state of parking brake and blade drive engager134is adjusted or changed.

Parking brake and blade drive engager134utilizes signals or mechanical force received from position sensor130to engage or disengage a single or pair of parking brakes150and one of more blade drives152(shown inFIG.3). Parking brakes150retain or resist motion of wheels326. When engaged, blade drive152transmits torque from prime mover332to blades344to rotate blades344. When disengaged, blade drive152disconnects blades344from prime mover332to inhibit the driving of blades344. In one implementation, blade drive152comprises a clutch or other selectable transmission component.

Engager134comprises a controller, such as the control board or electronic circuitry that, based upon the positioning of operator platform340, engages or disengages parking brake150and blade drive152. In response to operator platform340moving or pivoting to the fully raised position, indicating the absence of an operator, engager134automatically engages parking brake150and automatically disengages blade drive152. At the same time, prime mover332continues to operate or run, avoiding the need of having to be restarted to resume use of mower320. In one implementation, in response to the positioning of operator platform340moving or pivoting to the lowered position from the fully raised position, engager134automatically disengages parking brake150and automatically engages blade drive152, allowing immediate resumption of the use of mower120once the operator remount platform340. In yet another implementation, once the operator has the mounted platform340resulting in parking brake150being engaged in blade drive152being disengaged, remounting of platform340by the operator does not automatically disengages parking brake150and/or automatically reengage blade drive152. In such an implementation, additional confirming action or input from the operator is required to disengage parking brake150and/or reengage blade drive152.

FIG.18is a fragmentary rear perspective view of the mower320comprising operator platform position sensor330, a particular implementation of position sensor130. As shown byFIG.18, position sensor330comprises switch382and switch actuation linkage384. Switch382comprises an electrical contact switch actuatable between a closed state and an open state based upon a position of operator platform340. In the example illustrated, switch382is mounted to frame322above engine support platform386of frame322. Based upon the position of switch382, illogical signals are transmitted to parking brake and blade drive engager134(described above). In other implementations, switch382comprises other sensing devices such as a photo inventor-detector sensor or potentiometer.

Switch actuation linkage384comprises a rod having a first end388pivotably coupled to operator platform340and a second end390connected to switch382to actuate switch382. In the example illustrated, linkage384passes through engine support platform386between platform340and382. As a result, switch32is contained within frame322and is shielded from vegetation and other environmental conditions by platform386.

In operation, platform340is resiliently biased to a fully raised position by suspension324, such as by tension spring370(shown inFIG.13). In the fully raised position, linkage384interacts with switch382such that switch32is held in one of an open or closed state, indicating to engager134at platform340is in the fully raised position and that an operator is not present upon platform340. When an operator mounts platform340, platform340pivots to a lowered position. Pivoting of platform340to the lowered position results in linkage384being pulled downward such that switch32is actuated to the other of the open or closed state, indicating to engager134that platform340is no longer in the fully raised position and that the operator is present upon platform340. As noted above, engager134automatically actuates parking brake150and automatically disengages brake drive152in response to signals (or a lack thereof) indicating that an operator is no longer present upon platform340. In one implementation, engager134automatically disengages parking brake150and/or automatically engages brake drive152in response to signals (or lack thereof) indicating that an operator is once again present upon platform340. In other implementations, signals (or lack thereof) from switch32are used to additionally automatically enable, engage or disengage other operational components of mower320.

Although each of the above described integrated transaxles is disclosed as having its own dedicated housing, wherein the platform extends at least partially beneath each of the two housings of the two integrated transaxles, in other implementations, the left and right integrated transaxles are contained within a single housing. In such an implementation, the platform extends at least partially beneath the single housing. In yet other implementations, individual components of each integrated transaxle are housed or contained within multiple separate housings, wherein the platform extends at least partially beneath at least one of the multiple housings of each of the integrated transaxles.

Next, referring toFIGS.19-22, an operator platform and associated suspension system for a stand-on lawnmower400having an example suspension adjuster in accordance with another exemplary embodiment is shown.FIG.19shows a platform402pivotally supported at one end at least partially below respective left and right integrated transaxles404L,404R. Mounted on platform402is a two piece suspension adjustment plate406configured to retain a first end of a suspension adjustment linkage408. Suspension adjustment plate406is preferably mounted to platform402via welding, but may be mounted in any suitable way (e.g., fasteners) or integrally formed with platform402. Suspension adjustment linkage408is coupled to suspension adjustment plate406via a pin409, which is preferably toollessly removable via, e.g., a clevis pin.

Suspension adjustment linkage408is pivotally coupled at a second end411to a suspension link410. Suspension link410itself is pivotally coupled to a fixed bracket412at a pivot413that is mounted to a portion of the frame of mower400, as is more clearly shown inFIG.20. A suspension device414, e.g. a coil-over-shock device, is pivotally mounted to suspension link410at a pivot415, and is further pivotally coupled via a bushing416to bracket412, wherein bracket412holds a pin418which also pivotally supports bushing416. Suspension device414may be any suitable device for providing shock absorption to platform402.

When the user steps onto platform402to begin operating mower400, their feet are positioned on either side of suspension adjustment plate406. The weight of the operator causes an initial compression of suspension device414, as can be seen inFIGS.21and22. Due to varying weights of different operators of mower400, it is preferable for the platform suspension system to be adjustable to account for such weight variations. Accordingly, suspension adjustment plate406contains a plurality of holes407, wherein each hole407is configured to accept pin409. In this way, the compliance of platform402can be altered by simply changing the position of pin409in suspension adjustment plate406. In the position shown inFIGS.19-22, suspension adjustment linkage408is positioned at the “stiffest” setting, wherein platform402provides the most coil-over-shock suspension device414travel, which is particularly advantageous for heavier operators or others who prefer less platform travel. As suspension adjustment linkage408and pin409are moved to other holes407in suspension adjustment plate406that are closer to the pivot point of platform402, coil-over-shock suspension device414travel decreases, making the suspension more compliant for lighter operators. The farther coil-over-shock suspension device414travels, the more force it applies to supporting the platform.

Referring toFIGS.23-26, additional partial side views of mower400are illustrated.FIG.23shows platform402in its uncompressed state (i.e., no operator present), wherein suspension adjustment linkage408is set at the “stiffest” setting in suspension adjustment plate406.FIG.24depicts platform402with a hypothetical user present. As can be seen inFIG.24, the presence of an operator on platform402causes suspension link410to rotate, which in turn can more fully compress suspension device414and cause platform402to rotate into an increasingly horizontal position relative to its initial angle to better support a heavier operator.

FIGS.25and26, on the other hand, depict views of platform402with suspension adjustment linkage408set at the “lightest” setting. This reduces the potential travel of suspension device414and allows for greater overall angular movement of platform402for the lighter operator, as can be seen inFIG.26, which shows platform402having a hypothetical operator thereon and depicting the increased angular movement of platform402. Accordingly, an operator who is heavier or prefers more suspension travel may choose to position suspension adjustment linkage408at a hole407farther from the pivot point of platform402, while a lighter operator may choose to position suspension adjustment linkage408at a hole407closer to the pivot point of platform402.

Next, referring toFIGS.27-29, an operator presence system and neutral biasing mechanism in accordance with another exemplary embodiment is shown. Similar to mower400discussed above, a mower500comprises a suspension device514coupled to an operator platform, such as platform402shown inFIG.19, wherein suspension device514is pivotally coupled to a fixed bracket512on mower500via a bushing516on a pin518. Pin518is retained in slots519A,519B formed in bracket512, which allows for vertical translation of suspension device514. In one implementation, suspension device514and bracket512are identical to suspension device414and bracket412, respectively, described above, wherein suspension device514is pivotally mounted to suspension link410which is pivotally coupled to platform402by adjustment plate406and suspension adjustment linkage408as shown and described above with respect toFIGS.19-26.

In operation, an extension spring530shown inFIG.28pulls suspension device514down in slots519A,519B when an operator is not standing on platform502. Two forked tabs520A,520B are in contact with pin518and rotate about a rod522with respect to the frame of mower500. When suspension device514is pulled down in slots519(i.e., when an operator is not present on platform502), rod522rotates counterclockwise and in turn moves a control linkage tab524in a counterclockwise direction. Referring toFIG.29, control linkage tab524is coupled to a rod536, which is coupled at another end to a pin544and pivotal arm542. As a result, rotation of controlling524in the counterclockwise direction (as seen inFIG.27) pushes rod536upward to pivot arm542such that pin544experiences an upward force.

In the configuration shown inFIG.29, pin544is in contact with a notch545of a neutral biasing tab546. Neutral biasing tab546is coupled to the control levers538of mower500, which are capable of moving between a rear stop540A and a front stop540B to enable forward and rearward movement of mower500. Neutral biasing tab546and control levers538rotate about a pivot point548. When pin544is in contact with notch545of neutral biasing tab546, control levers538are biased to (and substantially locked in) their neutral position. Pin544is moved upward into contact with notch545, in response to rod536being pushed upward, when suspension device514is pulled down in slots519A,519B, which again occurs when there is no operator standing on platform502. Accordingly, the system shown inFIGS.27-29acts as an operator presence system, wherein the control levers538are unable to move out of the neutral position unless an operator is standing on platform502, and the control levers are biased to neutral once an operator steps off of platform502.

On the other hand, when an operator does step onto platform502, the operator's weight overcomes extension spring530and causes suspension device514to slide upward in slots519A,519B, thereby rotating rod522and control linkage tab524in a clockwise direction for an S inFIG.27). This, in turn, pulls rod536downward and pulls pin544downward out of detent or notch545of neutral biasing tab546, enabling control levers538to move freely between stops540A,540B.

Although the present disclosure has been described with reference to example embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the claimed subject matter. For example, although different example embodiments may have been described as including one or more features providing one or more benefits, it is contemplated that the described features may be interchanged with one another or alternatively be combined with one another in the described example embodiments or in other alternative embodiments. Because the technology of the present disclosure is relatively complex, not all changes in the technology are foreseeable. The present disclosure described with reference to the example embodiments and set forth in the following claims is manifestly intended to be as broad as possible. For example, unless specifically otherwise noted, the claims reciting a single particular element also encompass a plurality of such particular elements.