Abstract:
A construction machine is provided. The construction machine includes a chassis and a ground engaging member (such as a wheel or a track) operable to support and move the chassis over ground. The construction machine further includes a work implement (such as a bucket) coupled to the chassis; a cab mounted on said chassis and having a user seat, and a first controller (such as a joystick) accessible to a user seated in the user seat. The joystick controls at least one of moving the work machine over ground and movement of the bucket. The joystick has a first actuator (such as a trigger button) that is operable to selectively engage ride control functionality.

Description:
FIELD 
     The present invention relates to construction machines, such as skid steers and compact loaders, and, more particularly, to mechanisms for engaging and disengaging of ride control functionality on such construction machines. 
     BACKGROUND 
     Construction machines or vehicles, such as skid steers and compact loaders, generally include a chassis and a ground-engaging traction device coupled to the chassis and adapted to move the chassis along the ground. The chassis supports a cab in which the operator sits and operates the construction machine. A construction implement, such as a bucket, forklift, pile driver or grapple, is movably coupled to the chassis by lift arms, and is operated by the operator using controls located in the cab. Such construction machines often hold significant mass at the end of the lift arms. Such mass shifts the center of mass of the construction machine. Forces applied to mass at the end of the arms can cause instability. Terrains, such as jobsites, in which construction vehicles often operate are prone to being uneven. As a construction machine traverses uneven terrain, any instability presented by the holding of mass at a distance from the center of mass is potentially exposed. This exposed instability often results in a bumpy ride where the inertia of the mass of the implement imparts swaying (most prominently vertical swaying, but swaying in all directions is experienced). Such swaying can take portions of the ground-engaging traction device out of contact with the ground. 
     Accordingly, the concept of ride control was developed. Ride control, when activated, attaches an accumulator to hydraulic lines that impart movement to the lift arms. The attachment of the accumulator provides a “softer” connection between the lift arms and the cab. Thus, when uneven terrain imparts movement on the lift arms, implement, and any payload thereon, movement thereof is dampened by the accumulator and less movement is translated to the cab and the user. Thus, a smoother ride having increased likelihood of keeping the ground-engaging traction device in contact with the ground is provided. 
     However, as previously mentioned, attaching the accumulator to the hydraulic lines that impart movement to the lift arms provides a “softer” connection having reduced stiffness. When the implement is being used, such as when a bucket is being driven into a pile of dirt, stiffness is desired. A softer connection allows arm and implement deflection and reduces penetration into the pile. Accordingly, the effects of ride control are not desired for all times. 
     To this end, ride control is provided as a feature that can be turned on or off. Some implementations have placed the ride control switch outside of the cab such that a user has to exit the vehicle to turn it on or off. 
     It would be beneficial to provide a construction machine or vehicle having an improved mechanism for activating and deactivating ride control, such that the operator could more readily activate and deactivate ride control. It would be of further benefit if such mechanism also allowed the operator to activate and deactivate ride control while the vehicle is in motion. 
     SUMMARY 
     According to one exemplary embodiment of the present disclosure, a construction machine is provided. The construction machine includes a chassis and a ground engaging member (such as a wheel or a track) operable to support and move the chassis over ground. The construction machine further includes a work implement (such as a bucket) coupled to the chassis; a cab mounted on said chassis and having a user seat, and a first controller (such as a joystick) accessible to a user seated in the user seat. The joystick controls at least one of moving the work machine over ground and movement of the bucket. The joystick has a first actuator (such as a trigger button) that is operable to selectively engage ride control functionality. 
     According to another exemplary embodiment of the present disclosure, a construction machine is provided comprising a chassis, a ground engaging member operable to support and move the chassis over ground; a work implement coupled to said chassis; a cab mounted on said chassis and having a user seat, and a first controller accessible to a user seated in the user seat. The first controller includes a first actuator. The first controller is operable to control operation of the ground engaging member to move the work machine over ground and the first actuator operable to selectively engage ride control functionality. 
     According to another exemplary embodiment of the present disclosure, a method of selectively engaging ride control on a work machine is provided. The method including receiving input from a button on a joystick control, and selectively engaging ride control functionality based, at least partially, on the received input from the button on the joystick control. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a skid steer construction machine according to one embodiment of the present disclosure; 
         FIG. 2  is a diagrammatic view of the cab of the skid steer of  FIG. 1  according to one embodiment of the present disclosure; 
         FIG. 2A  is a close up of a operation controller of the skid steer cab of  FIG. 2  according to one embodiment of the present disclosure; 
         FIG. 3  is a plan view of a steering wheel according to a second exemplary embodiment of the present disclosure; 
         FIG. 4  is a diagram of parts of the skid steer of  FIG. 1 , according to one embodiment of the present disclosure; and 
         FIGS. 5A-C  show buttons within the cab of  FIG. 2  according to an exemplary embodiment of the present disclosure. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. Although the drawings represent embodiments of the present disclosure, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate and explain the present disclosure. Although the exemplification set out herein illustrates embodiments of the invention, in several forms, the embodiments disclosed below are not intended to be exhaustive or to be construed as limiting the scope of the invention to the precise forms disclosed. 
     DETAILED DESCRIPTION 
     The embodiments hereinafter disclosed are not intended to be exhaustive or limit the invention to the precise forms disclosed in the following description. Rather the embodiments are chosen and described so that others skilled in the art may utilize its teachings. 
     Referring first to  FIG. 1 , construction work machine  12  according to one embodiment of the present invention is illustrated. Construction machine  12  is illustrated as a skid steer. However, it should be understood that the concepts described herein may be adapted for incorporation into any suitable construction, agricultural and forestry equipment including, for example, compact track loaders, backhoes, dozers and other equipment. Construction machine  12  generally includes chassis  38 , ground engaging member  14  (a traction device) coupled to chassis  38 , construction tool or implement  28  coupled to chassis  38  and cab  36  supported on chassis  38 . Ground engaging member  14  is illustrated as a set of wheels, but may be any device capable of moving chassis  38  relative to the ground. For instance, ground engaging member  14  may be in the form of a track drive. Work implement  28  (a construction tool attachment) is operatively coupled to chassis  38  via lift arms  20 . Work implement  28  is shown as a post driver operable to drive post  50  into the ground. Other embodiments of work implement  28  are adapted to perform work such as digging, scraping, excavating or hauling in the form of any known tool, such as a broom, auger, grapple or forklift. 
       FIG. 4  diagrammatically shows additional portions of machine  12 . Vehicle control unit (VCU)  30  coordinates operation of machine  12 . VCU  30  is in communication with drivetrain  32 , which can include an engine, batteries, and a transmission. Drivetrain  32  controls traction devices  14 . VCU  30  is further in communication with hydraulic controller  34  to operate hydraulic pieces, such as lift arms  20  and implement  28 . Engagement management unit (EMU)  40  receives commands from VCU  30  to operate solenoids  42  which operate valves  44  as part of the ride control system and functionality. Valves  44  selectively place accumulator  46  in communication with the hydraulic circuits of lift arms  20 . 
     With reference to  FIG. 2 , cab  36  includes seat  22  supported on chassis  38 . Cab  36  further includes switches  18  and operation controllers  16 . Switches  18  are shown positioned at the top of cab  36  above the head of a seated user. Embodiments are envisioned where switches are also located at other locations in cab  36 . 
     In the shown example, operation controllers are joysticks  16   a,b , shown most clearly in  FIG. 2A . General joystick operation of skid steers is known. In one embodiment, joystick operation is conducted via the ISO standard. According to the ISO standard, joystick  16   a  controls operation of ground engaging members  14  to translate and turn machine  12  over the ground. According to the ISO standard, joystick  16   b  controls operation of lift arms  20  and implement  28 . Pressing forward on joystick  16   b  lowers lift arms  20  and pulling back raises lift arms  20 . Tilting joystick  16   b  right tilts implement  28  downward and tilting joystick  16   b  left tilts implement  28  upward. In another embodiment, joystick operation is conducted via an H-pattern standard (or H pattern with foot control). According to the H-pattern, forward and back movement of right joystick  16   a  controls forward and back movement of right side ground engaging members  14 . Similarly, forward and back movement of left joystick  16   b  controls forward and back movement of left side ground engaging members  14 . Left-right movement of one of joystick  16   a,b  controls up-down movement of lift arms  20  and left-right movement of the other of joysticks  16   a,b  controls the up-down tilting of implement  28 . Thus, it should be appreciated that in the instance of operation according to H-pattern, straight forward driving (or any driving other than spinning in a circle) requires a user to simultaneously operate both joysticks  16   a,b.    
     Joysticks  16   a,b  have various switches  24   a,b ,  26  (activators) mounted thereon. The switches can be designated for different things depending on various factors including, but not limited to, the specific implement  28  attached to lift arms  20 . In the present disclosure, the functionality of activator  26  (trigger) of joystick  16   a  is switchable via operation of switch  18   a . Switch  18   a  is more clearly shown in  FIGS. 5   a - c . Both activators  26  and  18   a  (discussed below) are illustratively “toggle” type switches (providing for continuous “on” or “off” as opposed to momentary “on” or “off”). 
       FIGS. 5   a - c  show switch  18   a  in various states. Switch  18   a  includes two indicators  52   a,b , which are illustratively LED&#39;s.  FIG. 5   a  shows switch  18   a  in a “ride control disabled” state. The “ride control disabled” state is indicated by the lack of illumination of both indicators  52   a,b . The state shown in  FIG. 5   a  prevents the activation of ride control functionality. Additionally, the state of  FIG. 5   a  causes operation of trigger  26  to selectively engage the “float” functionality for lift arms  20 . 
     Pressing switch  18   a  while in the state shown in  FIG. 5   a  causes switch  18   a  to assume the state shown in  FIG. 5   b  where indicator  52   a  is illuminated.  FIG. 5   b  shows switch  18   a  in a “ride control standby” state. The state shown in  FIG. 5   b  allows activation of the ride control functionality. The state shown in  FIG. 5   b  also provides that operation of trigger  26  no longer selectively engages the “float” functionality. The state shown in  FIG. 5   b  provides that operation of trigger  26  selectively engages the “ride control” functionality. 
     Pressing trigger  26  while in the state shown in  FIG. 5   b  causes activation of the “ride control” functionality. Pressing trigger  26  further causes illumination of indicator  52   b  of switch  18   a . Accordingly, ride control functionality is able to be activated by a press of trigger  26 . Furthermore, once switch  18   a  is pressed to put the system into “ride control standby,” ride control functionality is able to be activated without requiring a user to remove his hand from joystick  16   a . Similarly, ride control functionality can be deactivated without requiring a user to remove his hand from joystick  16   a . When ride control is active, a subsequent push of trigger  26  causes deactivation of ride control and a return to “ride control standby” mode of  FIG. 5   b . Also, when ride control is active, pressing button  18   a  returns the system to the “ride control disabled” state of  FIG. 5   a  which deactivates ride control and causes trigger  26  to control engagement of the “float” functionality. Any time that the system is in “ride control disabled” state, activation of switch  18   a  places the system into “ride control standby” regardless of whether the system was previously switched to “ride control disabled” from the “ride control standby” or the “ride control active” state. 
       FIG. 3  shows steering wheel  60  according to another embodiment of the present disclosure. Steering wheel  60  includes button  62  thereon. Button  62  selectively engages ride control functionality. Accordingly, while embodiments having joysticks and steering wheels with buttons thereon that selectively engage ride control are shown, embodiments are envisioned where all manner of driving controls and implement controls include actuators thereon that allow engagement of ride control functionality. Button  62  is illustratively a single function button that is exclusively responsible for selectively engaging ride control functionality. However, embodiments are envisioned where the function of button  62  is selected via operation of another button (not shown). 
     While this invention has been described as having an exemplary design, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.