Abstract:
A walk-behind self-propelled apparatus having a mobile structure and a handle assembly coupled to the mobile structure. The handle assembly includes a pair of grip portions. A ground engaging traction member is rotatably coupled to the mobile structure and imparts traction movement to the mobile structure for movement on the ground. A power source outputs drive power and a drive system, coupled between the power source and the ground engaging traction member, selectively transmits the drive power to the ground engaging traction member. A speed control actuation system coupled to the drive system includes a control member pivotable about an axis. An electronic member senses a control member rotation and relays an electronic signal to a controller which generates a linear speed control signal to the drive system.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of U.S. patent application Ser. No. 10/851,988 filed on May 21, 2004. The disclosure of the above application is incorporated herein by reference. 
     
    
     FIELD  
       [0002]     The present disclosure relates to powered equipment and, more particularly, relates to a speed control system for walk behind powered equipment that provides improved ergonomics, functionality, and safety.  
       BACKGROUND  
       [0003]     The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.  
         [0004]     As is known in the art, self propelled powered equipment is often used in a wide variety of applications, such as lawn mowers, greens mowers, roto-tillers, aerators, snowblowers, and the like. Self propelled powered equipment typically includes an engine, either an internal combustion engine and/or electric motor that is used to power a drive system. These drive systems traditionally include a friction device or gear train that transmits motive power from the engine to at least one drive wheel or roller. The drive system may be actuated in response to any one of a number of operator inputs, including gear shifters, levers, and the like. However, often these operator input systems are used to translate a cable coupled to the drive system to position the drive system in any one of a number of desired motive configurations.  
         [0005]     However, recently there has been an interest in improving the operation of these operator input systems. That is, there has been a need to improve the operation, reliability, durability, and safety thereof. Additionally, there exists a need in the relevant art to improve these input systems to simplify their operation and provide improved control. Additionally, there is a need in the relevant art to provide a speed control system that overcomes the disadvantages of the prior art.  
       SUMMARY  
       [0006]     According to the principles of the present disclosure, a walk-behind self-propelled apparatus having an advantageous construction is provided. The walk-behind self-propelled apparatus includes a mobile structure and a handle assembly coupled to the mobile structure. The handle assembly includes a pair of grip portions. A ground engaging traction member is rotatably coupled to the mobile structure and imparts traction movement to the mobile structure for movement on the ground. A power source outputs drive power and a drive system, coupled between the power source and the ground engaging traction member, selectively transmits the drive power to the ground engaging traction member. A speed control actuation system is then coupled to the drive system and includes a control member pivotable about an axis. The axis is generally parallel to a plane extending between the pair of grip portions of the handle assembly to permit an operator to operate the control member merely through thumb actuation without removing their hands from the pair of grip portions.  
         [0007]     Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
     
    
     DRAWINGS  
       [0008]     The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.  
         [0009]      FIG. 1  is a perspective view illustrating a greens mower according to the principles of the present disclosure;  
         [0010]      FIG. 2  is an enlarged perspective view of the speed control actuation system according to the principles of the present disclosure;  
         [0011]      FIG. 3  is an enlarged perspective view of a further embodiment of the speed control actuation system according to the principles of the present disclosure;  
         [0012]      FIG. 4  is an exploded assembly view of a further embodiment of the speed control actuation system according to the principles of the present disclosure;  
         [0013]      FIG. 5  is an exploded assembly view of an electronics package including a controller of the present disclosure;  
         [0014]      FIG. 6  is a partial exploded assembly view of an exemplary electric motor mounting assembly of the present disclosure;  
         [0015]      FIG. 7  is an exploded assembly view modified from  FIG. 5  to show an encoder substituted for the rotary potentiometer; and  
         [0016]      FIG. 8  is an exploded assembly view modified from  FIG. 5  to show a position sensor substituted for the rotary potentiometer. 
     
    
     DETAILED DESCRIPTION  
       [0017]     The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. For example, the present disclosure may find utility in a wide variety of applications, including use in lawn mowers, greens mowers, roto-tillers, aerators, snowblowers, and the like. However, in the following description, the present disclosure will be described in connection with a greens mower. Such description should not be regarded as limiting the present disclosure.  
         [0018]     With reference to the figure,  FIG. 1  illustrates a greens mower  10  incorporating the principles of the present disclosure. Greens mower  10  is a reel-type mower having a base portion  12  and a floating or articulating mowing unit  14 . Mowing unit  14  is articulately coupled to base portion  12  through a pivoting mechanism  16 .  
         [0019]     Mowing unit  14  includes a rotatable greens mower reel  18  having spiraled blades  20  equally spaced around a reel shaft  22 . Reel shaft  22  is generally elongated and defines a rotation axis  24  extending along the length of reel shaft  22 . A conventional fixed bed knife (not shown) is operably mounted to mowing unit  14 . Blades  20  orbit relative to shaft  22  and move past the fixed bed knife for the usual and well-known function of cutting the grass. Mowing unit  14  further includes a pair of ground engaging rollers  26  rotatably mounted along a forward and rearward portion of mowing unit  14 . The pair of ground engaging rollers  26  serve to support mowing unit  14  for movement on the ground. The pair of ground engaging rollers  26  are preferably adjustable to define a cutting height.  
         [0020]     Base portion  12  generally includes an internal combustion engine or electric motor  32 , a frame  34 , a lawn roller  36 , a drive system  38 , and a handle assembly  40 . Internal combustion engine or electric motor  32  is of conventional design and is mounted on frame  34 . Internal combustion engine or electric motor  32  may include an electric starter for improved convenience.  
         [0021]     Lawn roller  36  is rotatably mounted to frame  34  through a roller axle  46 . Lawn roller  36  supports base portion  12  on the ground and serves as the traction drive for greens mower  10 . Other ground-supporting traction members could be substituted. Drive system  38  is operably coupled between an output shaft  48  and lawn roller  36 . Drive system  38  generally includes a drive pulley (not shown) mounted to output shaft  48  for rotation therewith and an idler pulley (not shown) mounted to lawn roller  36  for rotation therewith. A drive belt (not shown) extends between the drive pulley and the idler pulley to transfer drive force from internal combustion engine or electric motor  32  to lawn roller  36 . Thus, there exists a traction drive train from internal combustion engine or electric motor  32  to the ground-engaging lawn roller  36  capable of driving greens mower  10  in at least a forward direction.  
         [0022]     As best seen in  FIG. 2 , handle assembly  40  includes a handle  50  suitably connected with frame  34 . Handle  50  includes a grip portion  52  which the operator can hold in steering greens mower  10 . A top portion  53  interconnects distal ends of grip portions  52  and a bottom portion  55  interconnects proximal ends of grip portions  52 . Bottom portion  55  of handle  50  defines a longitudinal axis A-A.  
         [0023]     A movably mounted bail or operator hand control  54  may be pivotally connected to handle  50  and may be movable toward and away from the grip portion  52 . The operation of hand control  54  may be similar to that disclosed in commonly owned U.S. Pat. No. 6,523,334, which is incorporated herein by reference. In this arrangement, the operator can hold both handle  50  and hand control  54  while guiding greens mower  10 . Upon release of hand control  54 , traction drive system  38  is interrupted in a manner similar to that disclosed in the &#39;334 Patent.  
         [0024]     Additionally, handle assembly  40  includes a speed control actuation system  60  operable to provide a control input to actuation traction drive system  38 . Specifically, speed control actuation system  60  includes a paddle member  62  pivotally coupled to handle assembly  40 . More particularly, paddle member  62  is generally planar in construction and generally U-shaped having a pair of upwardly projecting end portions  64 . End portions  64  are disposed within thumb reach of grip portion  52  of handle  50  such that an operator may actuation paddle member  62  without removal of their hands from grip portion  52 , as will be described below.  
         [0025]     Still referring to  FIG. 2 , paddle member  62  is pivotally mounted to a base portion  65  of handle  50  for rotation about an axis B-B. Axis B-B is generally oriented normal to axis A-A. In other words, axis B-B is generally parallel to a plane extending through grip portions  52 , top portion  53 , and bottom portion  55  of handle  50 . In this regard, paddle member  62  is pivotable in either direction about axis B-B by the simple application of thumb pressure from the operator. Paddle member  62  includes a generally turned flange  67  to permit the coupling of paddle member  62  to a shaft  70 .  
         [0026]     Paddle member  62  is operably coupled to a cable member  66  extending to traction drive system  38 . Cable member  66  transfers a control force to traction drive system  38 , thereby providing at least a forward propulsion command and, optionally, a rearward propulsion command in a convention manner. According to a first embodiment as seen in  FIG. 2 , cable member  66  is disposed about a pulley  68 . Pulley  68  is contained within base portion  65  of handle  50  and is fixed for rotation with a shaft  70  downwardly extending from paddle member  62  through axis B-B. A return cable member  66 ′ may be used to provide a fore and aft control movement or, alternatively, cable member  66  may be spring biased in a direction opposing paddle member  62 . According to an alternative embodiment as seen in  FIG. 3 , a cable member  166  is operably coupled to paddle member  62  through conventional means, including fasteners, a physical relief formed in paddle member  62  that cooperates with an oversized section of cable member  166 , or other systems. Cable member  166  is biased in tension via a spring member  168 . In this regard, as paddle member  62  is actuated, force is applied to cable member  166  against the biasing force of spring member  168  to provide a commanded drive operation to traction drive system  38 . Upon release of the pressure on paddle member  62 , spring member  168  returns cable member  166  and paddle member  62  to a neutral position.  
         [0027]     During operation, an operator can apply a controlling pressure with their thumb to one of the pair of upwardly projecting end portions  64  of paddle member  62  without removing their hand from grip portion  52  to command a desired drive movement, such as to increase travel speed. Such pressure causes paddle member  62  to rotate about shaft  70  (axis B-B) in a first direction, thereby rotating pulley  68  and applying a retracting force along cable member  66 , thereby actuating traction drive system  38  in a convention manner. Alternatively, such pressure against paddle member  62  in the first direction, applies a retracting force to cable member  166 , thereby actuating traction drive system  38 . To decrease travel speed or engine a reverse drive gear of traction drive system  38 , the operator then applies a controlling pressure with their thumb to the opposite upwardly projecting end portion  64  of paddle member  62  without removing their hand from grip portion  52 . Such opposing control input causes paddle member  62  to rotate about shaft  70  (axis B-B) in a second direction opposite of the first direction, thereby rotating pulley  68  and apply either an opposing retracting force along return cable member  66 ′ or simply permitting the biasing force in cable member  66  to retract cable member  66 , or similarly permitting the biasing force of spring member  168  to retract cable member  166 . This motion then commands either a slow drive movement and/or a reverse drive movement.  
         [0028]     Referring to  FIG. 4 , a speed control system  200  includes a handle assembly  202 , which is connected by a mounting bracket  204  to a tilt plate  206  using a plurality of fasteners  208 . Tilt plate  206  is in turn connected to a handle attachment plate  210  using a plurality of fasteners  216 . A bail lever  212  is rotatably connected between tilt plate  206  and handle attachment plate  210  in a bail lever receiving channel  214 . A handle  218  is fixably connected to handle attachment plate  210 .  
         [0029]     A throttle plate  220  similar to paddle member  62  of  FIG. 2  includes a sleeve  222  which is rotatably received within a bearing sleeve  223  created in handle attachment plate  210 . A shaft  224  of a rotary potentiometer  225  is received through bearing sleeve  223  and a shaft aperture  226  of throttle plate  220 . Shaft  224  is fixed with respect to throttle plate  220  using a screw  227 . Rotation of throttle plate  220  therefore acts to rotate shaft  224  of rotary potentiometer  225 .  
         [0030]     Referring to both  FIGS. 1 and 4 , a first brake cable  228  and a second brake cable  230  are connected to mounting plate  232  which is fixed to handle assembly  202 . A force transmitting cable  234  is also connected to mounting plate  232 . Cable  234  receives a force input from bail lever  212  such that rotation of bail lever  212  is required by an operator of the mower or powered device in order to release the brakes and permit powered motion of greens mower  10 . Cable  234  is also connected to a bail cable arm  235 . An independent brake lever  236  which is rotatably received in a sleeve  238  connected to handle assembly  202  is further capable of setting or releasing the brakes of greens mower  10  by connection to each of first and second brake cables  228 ,  230 . Brake lever  236  is rotatably received in sleeve  238  using first and second flanged bearings  240 . Rotation of brake lever  236  induces rotation of a brake arm  242  which extends or retracts first and second brake cables  228 ,  230 .  
         [0031]     Speed control system  200  can further include a rotary switch  244  which can be used in conjunction with the brake system to shut off the internal combustion engine or electric motor  32  for example when bail lever  212  is released. A top cover member  246  and a bottom cover member  248  can be used for handle assembly  40 . Top cover member  246  and bottom cover member  248  are provided to protect the members of speed control system  200  from various environmental conditions. Top and bottom cover members  246 ,  248  are fastened together using a plurality of cover fasteners  250 . A key  252  is shown in its inserted position. Key  252  can be used to start or stop greens mower  10 .  
         [0032]     Rotary potentiometer  225  is connected to additional components of speed control system  200  (shown in reference to  FIG. 5 ) using a connector  254  and a potentiometer harness  256 . Rotation of shaft  224  of rotary potentiometer  225  creates an electrical signal based substantially on a difference in resistance as shaft  224  is rotated. This change in resistance can be measured or applied in a linear progression defining an output signal having a linear range of output values for rotary potentiometer  225 .  
         [0033]     Referring now to  FIG. 5 , speed control system  200  further includes an electronics package  258 . Electronics package  258  provides a connector  259  to which connector  254  of rotary potentiometer  225  is connected. The output from rotary potentiometer  225  is therefore communicated from potentiometer harness  256  through a first wiring harness  260  into an LCD display unit  261  which is mounted as previously shown in  FIG. 4  in top cover member  246 . In addition to LCD display unit  261 , the signals from rotary potentiometer  225  are transferred via a second wiring harness  262  to a controller  264 . Controller  264  provides features to set at least minimum and maximum set points for the signal received from rotary potentiometer  225 . In a null or first position of rotary potentiometer  225  a minimum set point is established in controller  264 . Referring back to  FIG. 4 , throttle plate  220  is then rotated to its maximum position defining a maximum rotated position of shaft  224  of rotary potentiometer  225 . At this maximum rotated position a second set point is defined in controller  264 . Controller  264  is then capable of establishing a linear scale between the minimum and maximum set points one and two such that rotation of shaft  224  by rotation of throttle plate  220  creates an infinite range of values between the minimum and maximum set points. Increasing the rotation of throttle plate  220  provides a linearly changing signal from rotary potentiometer  225 . The output signal from controller  264  can be used to control the operating speed of either a first or second electrical motor  266 ,  268  which can be used for example to control the ground speed of the mower assembly or a rotational velocity of a real assembly.  
         [0034]     Electronics package  258  can further include a bail lever potentiometer  270  which similarly outputs a signal depending upon the rotated position of bail lever  212  shown in  FIG. 4 . The output signal from bail lever potentiometer  270  is similarly communicated through first wiring harness  260  into LCD display unit  261  and via second wiring harness  262  to controller  264 . A key switch  272  is adapted to receive the rotary motion of key  252  shown in  FIG. 4  to control the start and stop sequence of greens mower  10 . A reel switch  274  can also be provided which provides manually selectable on-off positions allowing an operator to manually switch off or on a reel blade assembly during operation of greens mower  10 . Electrical power carried through each of the first and second wiring harnesses  260 ,  262  can further be protected using a circuit breaker  276 .  
         [0035]     Referring to  FIG. 6 , any of the electrical motors  266 ,  268  can be further directly connected to frame  34  (shown in  FIG. 1 ) using a plurality of fasteners  278 . A clamp  280  can further be provided which is attached by one or more of the fasteners  278  and provides for support of a third wiring harness  282  extending from controller  264 . The controller  264  is adaptable to create a linear speed control signal which is used to control the speed of the greens mower  10  varying from the first or minimum signal defined at the null position and the second or maximum signal defined at the maximum rotated position of throttle plate, inclusive.  
         [0036]     Referring to  FIG. 7 , according to additional embodiments, an encoder  284  can be substituted for rotary potentiometer  225 . Encoder  284  is connected to controller  264  in a similar manner as rotary potentiometer  225  and also functions to create a linear speed control signal when throttle plate  220  is rotated, and is used to control the speed of the greens mower  10 .  
         [0037]     Referring to  FIG. 8 , according to additional embodiments, a position sensor  286  can be substituted for rotary potentiometer  225 . Position sensor  286  can also be connected to controller  264  in a similar manner as rotary potentiometer  225  and also functions to create a linear speed control signal when throttle plate  220  is rotated, and is used to control the speed of the greens mower  10 .  
         [0038]     The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.