WORK MACHINE WITH MULTIPLE HYDRAULIC TANKS

Abstract

A work machine comprising a frame configured to house a plurality of components of the work machine. The frame extends longitudinally from a rear end to a front end. The work machine further comprises a hydraulic system configured to provide hydraulic power to one or more hydraulically-powered components of the work machine. The hydraulic system includes a primary tank configured to hold hydraulic fluid, a hydraulic pump or a hydrostatic transmission configured to provide hydraulic fluid from the primary tank to the one or more hydraulically-powered components, and a secondary tank configured to hold hydraulic fluid and in fluid communication with the primary tank. The secondary tank is spaced apart from, rearwardly and above, the primary tank.

Claims

1. A work machine comprising: a frame configured to house a plurality of components of the work machine, wherein the frame extends longitudinally from a rear end to a front end; and a hydraulic system configured to provide hydraulic power to one or more hydraulically-powered components of the work machine, wherein the hydraulic system includes a primary tank configured to hold hydraulic fluid, a hydraulic pump and/or a hydrostatic transmission configured to provide hydraulic fluid from the primary tank to the one or more hydraulically-powered components, a secondary tank configured to hold hydraulic fluid and in fluid communication with the primary tank, wherein the secondary tank is spaced apart from, rearwardly and above, the primary tank.

2. The work machine of claim 1, wherein the hydraulic system includes a conduit extending between the primary tank and the secondary tank, wherein the conduit is configured to facilitate transfer of hydraulic fluid between the primary tank and the secondary tank.

3. The work machine of claim 2, wherein the conduit is a first conduit, and where the hydraulic system includes a second conduit extending between the primary tank and the secondary tank, wherein the second conduit is configured to facilitate air communication between the primary tank and the secondary tank.

4. The work machine of claim 1, wherein the primary tank is located within a forward portion of the frame, and wherein the secondary tank is located within a rearward portion of the frame.

5. The work machine of claim 4, wherein the secondary tank includes a fill-level indicator on an exterior side of the secondary tank, wherein the fill-level indicator is configured to provide an indication of the amount of hydraulic fluid held within the secondary tank.

6. The work machine of claim 5, wherein frame includes an opening adjacent to the fill-level indicator, such that an operator of the work machine can view the fill-level indicator from an exterior of the work machine.

7. The work machine of claim 4, wherein the secondary tank includes a fill cap on an upper portion of the secondary tank, wherein the fill cap releasably covers a fill port of the secondary tank through which hydraulic fluid may be added to the secondary tank.

8. The work machine of claim 7, wherein the frame includes an access hatch located adjacent to the fill cap, wherein when the access hatch is opened and the fill cap is removed, an operator of the work machine can fill the secondary tank with hydraulic fluid via the fill port of the secondary tank from an exterior of the work machine.

9. The work machine of claim 7, wherein the access hatch includes a lock that selectively locks the access door.

10. The work machine of claim 4, wherein the secondary tank includes a breather assembly located on or adjacent to a top of the secondary tank, wherein the breather assembly permits fluid communication between an interior of the secondary tank and the exterior environment.

11. The work machine of claim 1, wherein the primary and secondary tanks are formed from plastic.

12. The work machine of claim 1, wherein the primary tank is sized to hold from 5 to 10 gallons of hydraulic fluid.

13. The work machine of claim 1, wherein the secondary tank is sized to hold from 0.5 and 3 gallons of hydraulic fluid.

14. The work machine of claim 1, wherein the work machine is a loader.

15. The work machine of claim 14, wherein the work machine is a track loader, and wherein the hydraulically-powered components comprise hydraulic motors configured to power tracks of the track loader.

16. The work machine of claim 14, wherein hydraulically-powered components comprise hydraulic cylinders associated with lift arms of the work machine.

17. The work machine of claim 14, wherein the hydraulically-powered components comprise an attachment tool configured to be removably attached to the loader.

18. A method of operating a work machine, wherein the work machine extends longitudinally from a rear end to a front end, said method comprising: (a) powering one or more hydraulically-powered components of the work machine, wherein said powering of step (a) includes providing hydraulic fluid, via a hydraulic pump or a hydrostatic transmission, from a primary tank to the hydraulically-powered components; and (b) providing hydraulic fluid from a secondary tank to the primary tank, wherein the secondary tank is spaced apart from, rearwardly and above, the primary tank.

19. The method of claim 18, wherein said providing of step (b) is performed by providing the hydraulic fluid through a first conduit extending between the primary tank and the secondary tank, and wherein the work machine further comprises a second conduit extending between the primary tank and the secondary tank, wherein the second conduit is configured to facilitate air communication between the primary tank and the secondary tank.

20. The method of claim 18, further including the step of providing hydraulic fluid to the secondary tank from outside of the work machine.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0007] Embodiments of the present invention are described herein with reference to the following drawing figures, wherein:

[0008] FIG. 1 is a front perspective view of a loader according to embodiments of the present invention;

[0009] FIG. 2 is a rear perspective view of the loader from FIG. 1;

[0010] FIG. 3 is a front elevation view of the loader from FIGS. 1 and 2;

[0011] FIG. 4 is a right side elevation view of the loader from FIGS. 1-3

[0012] FIG. 5 is a left side elevation view of the loader from FIGS. 1-4

[0013] FIG. 6 is a rear elevation view of the loader from FIGS. 1-5;

[0014] FIG. 7 is a top plan view of the loader from FIGS. 1-6;

[0015] FIG. 8 is a bottom plan view of the loader from FIGS. 1-7;

[0016] FIG. 9 is a side view of an interior space of a cab of the loader from FIGS. 1-8, with a portion of the cab removed to illustrate user controls of the loader;

[0017] FIG. 10 is a side elevation view of the loader from FIGS. 1-8, with a cab of the loader shown positioned in both a raised position (solid line) and a lowered position (in broken line);

[0018] FIG. 11 is a front perspective view of the loader from FIGS. 1-8, with a cab of the loader shown in a raised position;

[0019] FIG. 12 is a rear perspective view of the loader from FIGS. 1-8, with a rear access door of the loader illustrated in an open position;

[0020] FIG. 13 is another rear perspective view of the loader from FIGS. 1-8, with a portion of a frame of the loader cut away to illustrate internal components of the loader;

[0021] FIG. 14a is a left side elevation view of an interior space of a cab of the loader from FIGS. 1-8, with a portion of the cab removed to illustrate a main door in an intermediate position between a closed position and an opened position;

[0022] FIG. 14b is a left side elevation view of the interior space of the cab from FIG. 14b, with the main door the opened position;

[0023] FIG. 15a is a front perspective view of a cab of the loader from FIGS. 1-8, with a portion of the cab cut away to illustrate user controls of the loader, and with a graphic display and lap bar in a lowered, operating position;

[0024] FIG. 15b is a front perspective view of the cab from FIG. 15a, with the graphic display and lap bar in a raised, non-operating position;

[0025] FIG. 16 is a right side perspective view of the loader from FIGS. 1-8, with portions of the loader removed to illustrate a primary hydraulic tank and a secondary hydraulic tank within the loader;

[0026] FIG. 17 is another right side perspective view of the loader from FIG. 16, with portions of the loader shown in broken line to illustrate the primary hydraulic tank and the secondary hydraulic tank within the loader; and

[0027] FIG. 18 is a partial view of the loader from FIGS. 16 and 17, with portions of the loader removed to illustrate the secondary hydraulic tank in more detail.

[0028] The drawing figures do not limit the present invention to the specific embodiments disclosed and described herein. The drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the invention.

DETAILED DESCRIPTION

[0029] The following detailed description of the present invention references various embodiments. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense. The scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled.

[0030] In this description, references to one embodiment, an embodiment, or embodiments mean that the feature or features being referred to are included in at least one embodiment of the technology. Separate references to one embodiment, an embodiment, or embodiments in this description do not necessarily refer to the same embodiment and are also not mutually exclusive unless so stated and/or except as will be readily apparent to those skilled in the art from the description. For example, a feature, structure, act, etc. described in one embodiment may also be included in other embodiments, but is not necessarily included. Thus, the present technology can include a variety of combinations and/or integrations of the embodiments described herein.

Overview

[0031] Embodiments of the present invention are directed to a work machine, such as a loader 10, as illustrated in exemplary FIGS. 1-8. Broadly, the loader 10 may comprise a frame 12 supported on the ground by a drive assembly 14. As will be discussed in more detail below, in addition to supporting the loader 10 on the ground, the drive assembly 14 is configured to propel the loader 10 over the ground. The loader 10 may additionally comprise one or more (e.g., a pair of) loader arms 16 supported by the frame 12 and configured to be raised and lowered. The loader arms 16 are further configured to support various types of attachments 18 for performing various types of work, as required by an operator of the loader 10. The loader 10 may include an operator cab 20 supported by the frame 12. The cab 20 may, as illustrated by FIG. 9, house a seat 21 and one or more user controls 22 (e.g., buttons, switches, levers, joysticks, touchscreen displays, etc.). The user controls 22 may be used by the operator to control various functions of the loader 10, as will be described in more detail below.

[0032] As used herein, directional terms are from the perspective of an operator sitting in the seat 21 of the loader 10 in an operating position (i.e., facing a front end of the loader 10). Thus, the terms front, forward, or fore, mean a longitudinal direction towards the front end of the loader 10. It is noted that the attachment 18 is supported at the front end of the loader 10 by connections with front ends of the loader arms 16. The terms back, rear, rearward, or aft mean a longitudinal direction towards the back end of the loader 10, i.e., behind the cab 20. The term left or leftward means a left lateral direction from the perspective of the operator sitting in the cab 20 and facing forward, and the terms right or rightward means a right lateral direction from the perspective of the operator sitting in the cab 20 and facing forward.

[0033] The loader 10 of embodiments of the present invention may comprise a compact utility loader or a CUL, or may specifically comprise a compact track loader or CTL. As used herein the term loader means is a self-propelled work machine comprising one or more loader arms configured to support various interchangeable, attachments that are operably connected with front ends of the loader arms. The attachments may be tools that have hydraulically-driven auxiliary functions, such as augers, grinders, tillers, rollers, trenchers, digger derrick, or the like. However, the loader 10 may support non-hydraulic attachments, such as buckets, blades, or the like. Regardless, because the inventive loader 10 of the present invention may be compact, i.e., having a smaller size and weight than standard loaders, such compact loader may be much more maneuverable and provide more efficient load/weight distribution than standard loaders.

[0034] In more detail, in some embodiments, the loader 10 may have a front-to-back length (excluding the attachment 18) of between 60 and 100 inches, between 70 and 90 inches, or about 85 inches. The loader 10 may have a top-to-bottom height (as measured from a bottom of the drive assembly 14 tracks and a top of the cab 20) of between 50 and 100 inches, between 60 and 90 inches, between 70 and 80 inches, or about 85 inches. The loader 10 may have a lateral width (as measured between the outside lateral edges of the drive assembly 14 tracks) of between 36 and 56 inches, between 40 and 52 inches, or about 45 inches. The frame 12 of the loader 10 may have a lateral width (as measured between the outside lateral edges of the frame 12) of between 32 and 52 inches, between 36 and 48 inches, or about 41 inches. In some embodiments, the loader 10 will be configured with a ground clearance (as measured from the ground surface to a bottom side of the frame 12) of between 7 and 12 inches, between 8 and 10 inches, or about 9 inches. Given such dimensional characteristics, the loader 10 is configured with various enhanced features and functionalities (as described in more detail below), yet maintains an overall small footprint so as to increase maneuverability and to enhance accessibility of the loader to confined working areas/spaces.

[0035] Beginning with the frame 12 of the loader 10, the frame 12 may broadly form a housing that defines an interior compartment within which various components of the loader 10 (e.g., engine, hydraulic system, etc.) are housed and supported, as will be discussed in more detail below. The frame 12 may comprise a left side 23 (See FIG. 1) and a right side 24 (See FIG. 2), which are connected together via a bottom side 26 (See FIG. 2). The left side 23 and the right side 24 may each be configured as a sidewall, and the bottom side 26 may be configured as a bottom wall. As such, the frame 12 can present the interior compartment for supporting various components of the loader 10, as will be discussed in more detail below.

[0036] Furthermore, and with reference to FIGS. 10 and 11, as the frame 12 may comprise a forward portion 12 (a) and a rearward portion 12 (b). As such, the frame 12 may extend longitudinally from a rearward end (part of the rearward portion 12 (b)) to a forward end (part of the forward portion 12 (a)). In general, the forward portion 12 (a) of the frame 12 may have a height that is less than height of the rearward portion 12 (b). In some embodiments, the cab 20 may be hingedly connected to a top of the frame 12, such that the cab 20 can be selectively positioned in a closed, operating position (See, e.g., FIG. 22) and an open, raised position (See, e.g., FIGS. 10 and 11). Specifically, as shown in FIG. 10, a back side of the cab 20 may be hingedly connected to a top of the frame 12, near or at a front of the rearward portion 12 (b) of the frame 12. The hinge connection may be a lateral extending, horizontal connection, such that the cab 20 can be vertically raised and lowered. When in the closed, operating position, a front, lower portion of the cab 20 may be securely coupled, e.g., via threaded fasteners, latches, or other locking mechanisms, to securely hold the cab 20 in place (with respect to the frame 12) in the closed, operating position. Further, the loader 10 may include an access door 28 hingedly connected to the frame 12 at the back end of the loader 10, and configured to be selectively positioned in a closed position (See, e.g., FIGS. 2 and 6) and an open position (See, e.g., FIG. 12). Specifically, in some embodiments, a right side of the access door 28 may be hingedly connected to a back end of the right side 24 of the frame 20. The hinge connection may be a vertical connection, such that the access door 28 can be opened and closed about a vertical axis. A left side of the access door 28 may include a locking mechanism (e.g., a latch) that permits the access door 28 to be selectively coupled with the left side 23 of the frame 12, so as to maintain the access door 28 in the closed position.

[0037] In view of the above, the frame 12, in addition to the cab 20 and the access door 28, are configured to present (and selectively enclose) the interior compartment within which various components of the loader 10. Specifically, with the cab 20 and the access door 28 in the closed position, various components of the loader 10 are enclosed within the interior compartment. Furthermore, however, with the cab 20 and/or the access door 28 in the open position, certain of those various components within the interior compartment may be accessed for maintenance, repair, or the like. For example, and with reference to FIG. 11, the interior compartment of the frame 12 may house a power unit, such as a combustion engine 30 of the loader 10, at least a portion of which may be positioned within a rearward portion 12 (b) of the frame 12. It is noted that in some embodiments, the loader 10 may include a power unit in the form of an electric motor to power the loader 10, in place of (or in addition to) the combustion engine 30.

[0038] The interior compartment may additionally house one or more components of a hydraulic system that is used to power one or more hydraulically-powered components of the loader 10. The hydraulic system may comprise a hydraulic auxiliary pump 32 that may be operably connected to a front end of the engine 30, as well as a hydrostatic transmission 34 that may be operably connected to a front end of the auxiliary pump 32. As such, the engine 30 may provide rotary power to each of the auxiliary pump 32 and the hydrostatic transmission 34. As will be described in more detail below, the hydraulic system, and particularly the hydraulic pump 32, may provide hydraulic power to the loader arms 16 and to the attachments 18 of the loader 10, as necessary. The hydraulic system, and particularly the hydrostatic transmission 34, may provide hydraulic power to the drive assembly 14, as discussed in more detail below. In some embodiments, a flywheel 36 may be positioned between the engine 30 and the auxiliary pump 32 and the hydrostatic transmission 34. Such flywheel 36 may be used to maintain a consistent power output from the engine 30 during varying RPMs.

[0039] In certain embodiments, the loader 10 may include a pair of drive motors 38 positioned within the interior compartment of the frame 12, on either side of the auxiliary pump 32 (i.e., a left side drive motor 38 and a right side drive motor 38). Such drive motors 38 may be used to provide power to the drive assembly 14. Specifically, the hydrostatic transmission 34 may be configured to provide hydraulic power to the drive motors 38, which in turn provide rotary power to the drive assembly 14 (e.g., tracks or wheels) of the loader 10. In some embodiments, the loader 10 may be in the form of a compact track loader, such that the drive assembly 14 comprises a pair of tracks, as described in more detail below. However, the loader 10 may, alternatively, be propelled by one or more wheels in place of, or in addition to, tracks. Regardless, as discussed above, the interior compartment of the frame 12, may house the engine 30, the auxiliary pump 32, the hydrostatic transmission 34, the flywheel 36, and the drive motors 38, as well as various other components of the loader's 10 hydraulic system (e.g., one or more hydraulic fluid reservoir tank(s) (e.g., a plurality of hydraulic fluid reservoir tanks), filters, ride control valve, accumulator, brake valve, lines/conduits, etc.). In some embodiments, the engine 30 may be positioned within the rearward portion 12 (b) of the frame 12, while the auxiliary pump 32, the hydrostatic transmission 34, the flywheel 36, and the drive motors 38, as well as various other components of the loader's 10 hydraulic system may be positioned within the forward portion 12 (a) of the frame 12. Regardless, as described in more detail below, certain components of the loader's 10 hydraulic system may be positioned within the rearward portion 12 (b) of the frame 12.

[0040] Turning to the rearward portion 12 (b) of the frame 12 in more detail, as illustrated in FIGS. 12 and 13, various components of the loader 10 may be positioned within the internal compartment presented by the rearward portion 12 (b). For instance, as noted previously, the engine 30 (or at least a portion thereof) may be positioned within the rearward portion 12 (b) of the frame 12. A cooling system may be positioned rearward of the engine 30. In particular, the cooling system may comprise a fan 40 attached to a rear side of the engine 30. The cooling system may additionally comprise a radiator 42 positioned rearward of the fan 40. In some embodiments, as will be described in more detail below, the radiator 42 may be attached to the access door 28 and configured to rotate open and closed (with respect to the fan 40) in conjunction with the access door 28. In addition, the rearward portion 12 (b) of the frame 12 may house a heating, ventilation, and air-conditioning (HVAC) system 44, which is configured to provide temperature controlled airflow to the cab 20, as will be discussed in more detail below. Furthermore, the rearward portion 12 (b) of the frame 12 may house an actuator 46, as shown in FIG. 13, in operable engagement with the cab 20 and configured to selectively shift the cab 20 between open and closed positions, as noted above and as will be discussed in more detail below. The actuator may comprise an electro-hydraulic actuator, as well as various other types linear actuators. Finally, the rearward portion 12 (b) of the frame 12 may house various other components of the loader, such as components of the loader's 10 electrical system (e.g., battery, engine 30 starter, alternator), fuel tank, associated cables/lines, etc.

[0041] Notably, the cab 20 and the access door 28 being configured to selectively open and close provide access to the interior compartment of the frame 12. For example, the cab 20 can be raised to the open position to provide access to the engine 30, the auxiliary pump 32, the hydrostatic transmission 34, the flywheel 36, the drive motors and/or various other components of the loader's 10 hydraulic system. The access door 28 can be opened to provide access to the engine 30, the cooling system (e.g., the fan 40 and radiator 42), the HVAC system 44, electrical system, and/or other related components. Such access can facilitate efficient service and maintenance of the loader 10.

[0042] With reference to FIGS. 4 and 5, the drive assembly 14 of the loader may comprise a pair of endless tracks 50 that extend from the exteriors of the left side 23 and the right side 24 of the frame 12. In more detail, the drive assembly 14 may comprise a pair of track frames 52, with each track frame 52 being rigidly secured to one exterior side 23, 24 of the frame 12 of the loader 10. Specifically, the left side track frame 52 may be rigidly secured (e.g., via welding) to the left side 23 of the frame 12, so as to extend laterally away from the frame 12. Similarly, the right side track frame 52 may be rigidly secured (e.g., via welding) to the right side 24 of the frame 12, so as to extend laterally away from the frame 12. As shown in FIGS. 4 and 5, the track frames 52 may support one or more wheels rotatably secured thereto, so as to permit the tracks 50 to rotate around the track frames 52. Specifically, each track frame 52 may support a pair of idler wheels 54, with a front idler wheel 54 secured to a front of the track frame 52 and a rear idler wheel 54 secured to a rear of the track frame 52. In addition, each track frame 52 may support a plurality of roller wheels 56 (e.g., three roller wheels) secured to the track frame 52 between the idler wheels 54 in a front-to-back direction. Each of the roller wheels 56 be secured to a bottom of the track frame 52 via an independent suspension element so as to provide enhanced stability and driveability of the loader 10. In contrast, the idler wheels 54 may be directly secured to the track frames 52 via an axle.

[0043] One of the tracks 50 may loop around each of the track frames 52 and associated wheels (e.g., idler wheels 54 and roller wheels 56) so as to present a left track 50 and a right track 50. The tracks 50 may be formed from rubber, metal, or combinations thereof. Although the loader 10 is illustrated as having tracks 50, in some embodiments, the loader 10 may include one or more wheels on each side 23, 24 of the frame 12 to support and to propel the loader 10.

[0044] To facilitate rotation of the tracks 52, the drive assembly 14 may additionally comprise a pair of drive sprockets 58 positioned on either exterior side 23, 24 of the frame 12, as shown in FIGS. 4 and 5. Specifically, in some embodiments, a left side drive sprocket 58 may extend from the left side 23 of the frame 12 at a position above the left side track frame 52. Similarly, a right side drive sprocket 58 may extend from the right side 24 of the frame 12 at a position above the right side track frame 52. Each of the tracks 50 may be looped around the associated track frame 52, wheels (e.g., idler wheels 54 and roller wheels 56), and drive sprocket 58. As such, the tracks 50 may be configured in a triangular shape, when viewed from the sides of the loader 10. An interior surface of the tracks 50 may be formed with nubs that engage with teeth of the drive sprockets 58, such that rotation of the drive sprockets 58 will cause a corresponding rotation of the tracks 50. As such, the loader 10 can be propelled by rotating the drive sprockets 58, which causes rotation of the tracks 50. Specifically, the left side drive sprocket 58 may be operably connected with the left side drive motor 38, and the right side drive sprocket 58 may be operably connected with the right side drive motor 38, such that the drive motors 38 can drive the drive sprockets 58. As a result, the loader 10 can be propelled forward, rearward, and turn leftward/rightward.

[0045] Turning to the loader arms 16 of the loader 10, the loader arms 16 may comprise two loader arms 16 in the form of a left loader arm (i.e., positioned on a left side of the loader 10) and a right loader arm (i.e., positioned on a right side of the loader 10). Each of the loader arms 16 may have a rear end that is pivotably coupled with the frame 12 of the loader 10, near the back end of the loader 10. Each of the loader arms 16 may extend forward to a front end that supports a hitch assembly 60, as perhaps best shown in FIG. 2. Such hitch assembly 60 may extend at least partially between the left and right loader arms and may generally comprise one or more connection plates configurable to releasably secure various types of attachments 18 to the loader arms 16. The loader arms 16 may additionally include a cross-bar, as perhaps best shown in FIG. 1, that extends between the left and right loader arms 16. In certain embodiments, the cross-bar may be positioned adjacent to and behind the hitch assembly 60. Furthermore, in some embodiments, each of the loader arms 16 may include a tilt actuator 62, as shown in FIG. 1, that extends from the loader arm 16 to one of the lateral sides of the hitch assembly 60, so as to permit tilting of the hitch assembly 60 and any attachment 18 coupled with the hitch assembly 60. The tilt actuators 62 may comprise hydraulic cylinders (e.g., single or double-acting cylinders), pneumatic cylinders, and/or electric linear actuators. For example, if an attachment 18 in the form of a bucket is attached to the hitch assembly 60, actuation of the tilt actuators 62 will permit the bucket to be tilted such as for selectively collecting and dumping material. Finally, one or more of the loader arms 16 may include a hydraulic coupler 64, as shown in FIG. 1, with which one or more hydraulic lines may be coupled to provide hydraulic power to attachments 18 that operate on hydraulic power.

[0046] The loader arms 16 may be raised and lowered via lift actuators 66. In some embodiments, the lift actuators 66 may comprise linear actuators, such as hydraulic cylinders (e.g., single or double-acting cylinders), pneumatic cylinders, and/or or electric linear actuators. In more detail, each loader arm 16 may be associated with a lift actuator 66 that is pivotably coupled at a rearward end with one lateral side the frame 12. Each lift actuator 66 extends generally forward to a respective loader arm 16, such that a forward end of the lift actuator 66 is pivotably coupled with the loader arm 16 at a position between the rearward and forward end of the loader arm 16. In some embodiments, the frame 12 may include a cover panel 68 one each lateral side of the loader 10 that is spaced apart from the left side 23 and right side 24 of the frame 12. In certain embodiments, the cover panels 68 may cover rearward portions of the loader arms 16 and the lift actuators 66, so as to cover the connections between the loader arms 16 and the lift actuators 66 to the frame 12. In some embodiments, connection between the loader arms 16 and the lift actuators 66 to the frame 12 may also include a connection with the cover panels 68. Specifically, the rearward ends of the loader arms 16 and the lift actuators 66 may be positioned between the respective left or right sides 23, 24 of the frame 12 and the respective cover panels 68 of the frame, such that the rearward ends of the loader arms 16 and the lift actuators 66 are simultaneously rotatably coupled with both the left or right sides 23, 24 and the respective cover panels 68.

[0047] Because the rear ends of the loader arms 16 are rotatably coupled with the frame 12 at a fixed pivot point, the loader arms are configured in a pivot-lift configuration (also commonly referred to as a radial lift configuration). In such a configuration, the forward ends of the loader arms 16, and any attachment 18 coupled therewith, will generally travel in an arc-like or circular travel path. In some other embodiments (not shown in the drawings), the loader arms 16 may be configured in a vertical-lift configuration. In such a configuration, the entirety of the loader arms 16 shift position upward, downward, forward, and/or rearward with respect to the frame 12 of the loader 10 as the loader arms 16 transition between lowered and raised positions. As such, the forward ends of vertical-lift configured loader arms 16, and any attachment 18 coupled therewith, can travel along a substantially vertical travel path.

[0048] As noted previously, the cab 20 of the loader 10 may be rotatably coupled with the frame 12, as illustrated in FIG. 10, such that the cab 20 can be selectively positioned in a closed, operating position and in an open, raised position. The cab 20 may, as shown in FIGS. 1, 2, and/or 11, have a generally rectangular shape with a left side 71, a right side 72, a front side 73, a back side 74, a top side 75, and a bottom side 76. The sides 71-76 of the cab 20 may enclose an interior space within which an operator can be positioned to operate the loader, as will be disclosed in more detail below. Each of the left side 71, the right side 72, and the back side 74 may comprise a frame bordering a transparent material (e.g., plastic or glass) configured to operate as a window, such that an operator of the loader 10 can view the external environment. In certain embodiments, the back side 74 may comprise a lower portion and an upper portion. The upper portion may comprise the transparent material, while the lower portion may comprise a generally solid, sheet of material (e.g., steel). However, the lower portion may include one or more openings or ports configured to facilitate airflow into and out of the cab 20 from the HVAC system 44. In some embodiments, the top side 75 may also include one or more windows so as to permit light to enter the interior space of the cab 20.

[0049] The front side 73 of the cab 20 may comprise a frame that borders a main door 78. As shown in FIGS. 14a and 14b, the main door 78 may be attached to other components of the cab 20 via an actuation assembly 80 configured to permit the main door 78 to selectively transition back and forth between an opened position (e.g., FIG. 14b) and a closed position (e.g., FIG. 1). It is noted that FIG. 14a illustrates the main door in a transition state between the opened position and the closed position. The main door 78 may comprise a transparent material (e.g., plastic or glass) configured to operate as a window. With the main door 78 in a closed position (i.e., positioned generally parallel with and adjacent to the frame of the front side 73 as shown in FIG. 1), the door 78 acts as a window, such that the operator can view forward so as to observe the environment, the loader arms 16, the attachment 18, etc. of the loader 10. When the main door 78 in an open position, as shown in FIG. 14b (i.e., positioned generally parallel with and adjacent to the top side 75), the main door 78 is actuated away from the front side 73 of the cab so as to present an open entryway 82 through which an operator can enter and exit the interior space of the cab 20.

[0050] With reference to FIG. 11, the bottom side 76 of the cab 20 may comprise a main platform 84 on which the seat 21 is positioned within the interior space of the cab 20. The bottom side 76 may additionally comprise a lowered platform 86 positioned forward of the main platform 84, and is configured to receive the feet of the operator of the loader 10 when the operator is seated on the seat 21 to operate the loader 10.

[0051] Turning to FIGS. 15a and 15b, the interior space of the cab 20 includes a plurality of user controls 22 (e.g., buttons, switches, levers, joysticks, touchscreen displays, etc.) that the operator can access and manipulate when the operator is seated on the seat 21. As such, the interior space of the cab 20 may be referred to as a control station. In more detail, the seat 21 may include a pair of armrests on which a user may rest his/her arms when seated in the seat 21 and operating the loader 10. A control panel 90 with one or more user controls 22, in the form of buttons, switches, or levers, may be positioned forward of one of the armrests. The operator may select such user controls 22 on the control panel 90 to perform various functions of the loader, such as (i) providing electrical power from the battery to various components of the loader, (ii) turning on/off vehicle lights of the loader, which may be positioned on exterior portions of the cab 20, (iii) starting the engine 30 of the loader 10.

[0052] In addition, a pair of joysticks 92 may be positioned forward of the armrests such that an operator can comfortably reach the joysticks 92 when seated in the seat 21. A first of the joysticks 92 may be a loader arm & attachment (LA&A) joystick 92 (a) for controlling actuation of the loader arms 16 (e.g., raising and lowering) and various hydraulically-operated functions of the attachment 18 that may be supported on the front of the loader arms 16. For example, the hydraulically-operated functions may include a tilt function for buckets or auxiliary hydraulic functions for other hydraulically-operated attachments 18 such as, e.g., bit rotation of a drill, bit actuation of a jack-hammer, rotation of a blade for a saw, rotation of multiple blades for a rotary cutter, brush rotation of a sweeper, etc. In addition, a second of the joysticks 92 may include a drive joystick 92 (b), which is configured to control actuation of the tracks 50 (e.g., via control the drive motors 38 and the sprockets 58) for controlling overall movement (e.g., travel direction and speed) of the loader 10. In more detail, the drive joystick 92 (b) may extend upward in front of the armrests, such that an operator may grasp and shift the drive joystick 92 (b) so as to cause a corresponding movement of the loader 10. In certain embodiments, the loader 10 may include an electric-over-hydraulic (EOH) system, such that the joysticks 92 may generate electric signals, which are configured to control hydraulic components of the loader 10.

[0053] In addition, the user controls 22 may include a graphic display 94 comprising an electronic display, such as a cathode ray tube, liquid crystal display, plasma, or touch screen that is operable to display visual graphics, images, text, etc. In embodiments in which the graphic display 94 is a touchscreen, the operator can manipulate the graphic display 94 to control various aspects and/or functionalities of the loader 10. The graphic display 94 may include, or may otherwise be associated with, one or more memory elements and processing elements. The memory elements may comprise non-transitory computer readable media and/or firmware, with a computer program stored thereon. The processing elements may comprise processors, CPUs, FPGAs, etc., which are configured to execute computer programs stored on the memory elements to perform various functions and features of the loader 10. It should be understood that certain of the loader's 10 functions and features discussed above and below may be performed by execution of the computer program by the processing elements. For example, the graphic display 94 may be configured to (by the processing elements executing the computer program stored on the memory elements) (i) obtain information from various components of the loader 10 (e.g., via sensors, actuators, timers, clocks, etc.) so as to present such information to the operator via the graphic display 94, and (ii) receive instructions from the operator (e.g., via the graphic display 94 or other of the control elements 24) to control various operations of the loader 10. For example, the graphic display 94 may present various graphical user interfaces (GUIs) that provide information to the operator and/or that facilitate interaction and control of the loader 10 by the operator. In embodiments in which the graphic display 94 is a touchscreen, the GUIs enable the operator to interact with the loader 10 by touching display areas of the GUI. In some other embodiments, the operator will interact with the GUIs and/or the loader by manipulating interactable graphical icons/elements that are associated with the graphic display 94. The functionality of the graphic display 94 will be described in more detail below.

[0054] As illustrated in FIGS. 15a and 15b, the graphic display 94 may be coupled to an end of a rotatable lap bar 96. As such, the graphic display 94 and the lap bar 96 may be selectively shiftable between a raised, non-operable position (i.e., FIG. 15b) and a lowered, operating position (i.e., FIG. 15a). In the raised, non-operable position, the graphic display 94 and the lap bar 96 are rotated away from the seat 21 such that space is provided for the operator to access or disembark from the seat 21. Once the operator has sat down in the seat 21, the graphic display 94 and the lap bar 96 can be rotated down towards the seat, such that the graphic display 94 is positioned in the lap area of the operator. As such, the operator can easily interact with the graphic display 94 to obtain information for and/or control functions of the loader 10. In some embodiments, the loader 10 may include a position sensor associated with the lap bar 96 and configured to determine if the lap bar 96 is in either the raised, non-operable position or the lowered, operating position. In some embodiments, certain functions of the loader 10 may not be operable unless the lap bar 96 is in the lowered, operating position. In addition, some embodiments may provide for the seat 21 to include a presence sensor configured to determine whether an operator is seated in the seat 21. In some embodiments, certain functions of the loader 10 may not be operable unless the operator is seated. The above-described position/presence sensors may comprise electronic sensors, such an inductive proximity switch configured to be triggered by the position of the lap bar and/or weight of the operator present in the seat 21. Thus, the loader 10 is configured to determine whether or not an operator is positioned within the seat 21 and with the lap bar 96 in the lowered, operating position. In some embodiments, certain operational features of the loader 10 may be restricted (e.g., starting the engine 30 of the loader, maneuvering the loader 10, actuating the loader arms 16 and/or attachment 18, etc.) if an operator is not present in the seat 21 and/or the lap bar 96 is not positioned in the lowered, operating position.

Hydraulic Reservoir Tanks

[0055] As briefly noted previously, the hydraulic system of the loader 10 may include a plurality of hydraulic oil reservoir tanks. For example, as illustrated in FIG. 11, the hydraulic system may include primary tank 102, which is positioned within the interior space of the forward portion 12 (a) of the frame 12. The primary tank 102 may be made of plastic and may be configured to hold hydraulic fluid. In some embodiments, the primary tank 102 may be sized to hold from 5 and 10 gallons, between 6 and 8 gallons, and/or about 7 gallons of hydraulic fluid. As such, the primary tank 102 can supply hydraulic fluid to (or receive hydraulic fluid from) various hydraulically-powered components of the loader 10.

[0056] For example, hydraulic fluid may be transferred from the primary tank 102, via the hydraulic pump 32, to the hydraulic cylinders (e.g., tilt cylinders 62 and/or lift cylinders 66) and/or to the attachments 18, so as to actuate the hydraulically-powered components of the loader 10 (e.g., the tilt cylinders 62, lift cylinders 66, and/or to the attachments 18). After actuation of such hydraulically-powered components has been completed, hydraulic fluid can return into the primary tank 102. In addition, hydraulic fluid may be transferred from the primary tank 102, via the hydrostatic transmission 34, to the drive motors 38, so as to actuate such hydraulically-powered components to propel the loader 10. After actuation of such hydraulically-powered components has been completed, hydraulic fluid can return into the primary tank 102.

[0057] In some embodiments, the hydraulic system of the loader 10 may additionally comprise a secondary tank 104, as illustrated in FIGS. 12 and 13. The secondary tank 104 may be in the form of a reserve tank that is positioned within the interior space of the rearward portion 12 (b) of the frame 12. The secondary tank 104 may be made of plastic and may be configured to hold hydraulic fluid. In some embodiments, the secondary tank 104 may be sized to hold from 0.5 and 3 gallons, between 1 and 2 gallons, and/or about 1.5 gallons of hydraulic fluid. As such, the secondary tank 104 can supply hydraulic fluid to (or receive hydraulic fluid from) the primary tank 102.

[0058] In view of the above, and as illustrated in FIGS. 16 and 17, at least a portion of (or the entirety of) the secondary tank 104 may be positioned rearward and vertically above the primary tank 102. For instance, the secondary tank 104 may be positioned in the rearward portion 12 (b) of the frame 12, while the primary tank 102 may be positioned in the forward portion 12 (a) of the frame 12. Nevertheless, the primary and secondary tanks 102, 104 may be fluidly connected via one or more conduits. For instance, as illustrated in FIG. 16, a first conduit 106 may extend from a lower portion of the secondary tank 104 forward to a lower portion of the primary tank 102. The first conduit 106 may generally be configured to permit hydraulic fluid to flow between the primary and secondary tanks 102, 104. A second conduit 108 may extend from an upper portion of the secondary tank 104 forward to a lower portion of the primary tank 102. The second conduit 108 may generally be configured to permit air to flow between the primary and secondary tanks 102, 104. In some embodiments, the first conduit 106 may be larger in diameter than the second conduit 108, to account for differences in compressibility between hydraulic fluid and air.

[0059] Turning to the secondary tank 104 in more detail, as shown in FIGS. 17 and 18, the secondary tank 104 may have a removable fill cap 110 on a top of the tank 104. The fill cap 110 removably covers a fill port of the secondary tank 104, such that removal of the fill cap 110 from the fill port allows hydraulic fluid to be added to the secondary tank 104 and, thus, to the hydraulic system of the loader 10. The secondary tank 104 may also include a breather cap 112 on the top of the tank 104, which permits the pressure within the secondary tank 104 to be normalized with respect to ambient pressure. Specifically, the breather cap 112 may provide fluid communication between an interior of the secondary tank 104 and the exterior environment. By having the breather cap 112 position on the top of the secondary tank 104, oil is inhibited from splashing out of the tank 104 via the breather cap 112 as hydraulic fluid moves throughout the secondary tank 104 during operation of the loader 10.

[0060] Furthermore, as perhaps best shown in FIG. 18, the secondary tank 104 may include a fill-level indicator 114 (e.g., a sight glass) on an exterior side panel of the tank 104, which permits a user to visually determine the fill level of hydraulic fluid within the secondary tank 104. In some embodiments, a portion of the frame 12 (e.g., the right side 24 of the frame 12 and/or the right cover panel 68 of the frame 12) of the loader 10 may include an opening or a port 115, as illustrated in FIGS. 4 and 18, that is aligned with the fill-level indicator 114, such that the operator can view the fill-level indicator 114 from outside the loader 10 to determine the fill level of hydraulic fluid within the secondary tank 104.

[0061] If additional hydraulic fluid is required to be added to the hydraulic system, the frame 12 may include an access hatch 116, as illustrated in FIG. 18, positioned above the secondary tank 104, directly above the fill cap 110 and/or the breather cap 112, such that the operator can open the access hatch 116 to obtain access to the fill cap 110 to add hydraulic fluid to the secondary tank 104. Specifically, the operator can open the access hatch 116 and remove the fill cap 110, such that the operator can add hydraulic fluid into the secondary tank 104 via the fill port of the tank 104. If spillage occurs during filling of the secondary tank 104, such spillage will generally be on the outside of the loader, where cleanup is easier. In contrast, if it were required to refill hydraulic fluid via the centrally-positioned primary tank 102, such cleanup would be more difficult. In addition, by accessing the access hatch 116, the operator can readily perform maintenance on the breather cap 112. As illustrated, the access hatch 116 is removably coupled (or perhaps hingedly coupled) to remaining portions of the frame 12, and may include a key-activated lock to selectively lock and unlock the access hatch 116 for purposes of safety/security.

[0062] The above-described embodiments of the hydraulic system provides various benefits. For instance, by having two, separate hydraulic tanks, one tank (e.g., the primary tank 102) can be centrally positioned at a lower point within the frame 12 (e.g., within the front portion 12 (a) of the frame 12), near the various components of the hydraulic system (e.g., the hydraulic pump 32 and/or hydrostatic transmission 34) so as to hydraulically connect the primary tank with such components of the hydraulic system using a minimal amount of hydraulic lines (and/or hydraulic lines with reduced lengths). Such a reduction in hydraulic lines can save significant space within the loader 10. In addition, the other tank (e.g., the secondary tank 104) can be positioned closer to the exterior of the loader 10 at a higher position within the frame 12 (e.g., within the rear portion 12 (b) of the frame 12), so as to provide operators of the loader with efficient access to the secondary tank from the exterior of the loader 10 for purposes filling and performing maintenance on the hydraulic system. If spillage occurs when filling the secondary tank from outside the loader 10, such spillage on the outside of the loader 10 is easier to clean than spillage within the interior space of the frame 10 (i.e., where the primary tank is located).

[0063] The secondary tank 104 also provides extra volume within the hydraulic system so as to facilitate thermal expansion of the hydraulic fluid during operation of the loader 10. And by positioning the secondary tank 104 above the primary tank 102 (at a higher height), more hydraulic head pressure can be generated within the primary tank 102 (due to the potential energy of the hydraulic fluid stored in the elevated secondary tank 104).

[0064] Although the invention has been described with reference to the one or more embodiments illustrated in the figures, it is understood that equivalents may be employed and substitutions made herein without departing from the scope of the invention as recited in the claims.

[0065] Having thus described one or more embodiments of the invention, what is claimed as new and desired to be protected by Letters Patent includes the following: