Steering system and off-road vehicle

Abstract

The utility model relates to a steering system. In one example, a steering system includes a hydraulic cylinder for adjusting a steering angle of a wheel connected to an axle and a pair of hydraulic ports including an inboard portion in sealing engagement with an outer circle of a hydraulic cylinder tube. In addition, the utility model further relates to an off-road vehicle.

Description

Technical Field

[0001] This description generally relates to steering cylinders for vehicles. Background Art

[0002] The vehicle may include a drivetrain with a power source, a transmission, and a drive axle. The vehicle (in one example, an off-highway vehicle) may include a steering column for controlling a pair of wheels of the vehicle.

[0003] The steering cylinders of some off-highway vehicles may include hydraulic ports for introducing hydraulic fluid into the hydraulic chamber of the steering cylinder barrel. Some designs may reduce the vehicle's turning range and / or turning radius because the location of the ports and / or the hoses extending therefrom may interfere with the turning wheels. Therefore, an improved system is needed to modify the steering cylinder design. Utility Model Content

[0004] In one example, the above problems can be at least partially addressed by a steering system that includes a hydraulic cylinder for adjusting the steering angle of wheels connected to an axle, and a pair of hydraulic ports, each of the hydraulic ports including an inner portion that sealingly engages an outer periphery of a hydraulic cylinder tube.

[0005] It should be understood that the above summary is intended to introduce concepts further described in the detailed description in a simplified form. It is not intended to identify key or essential features of the claimed subject matter, the scope of which is determined solely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Those skilled in the art will readily appreciate the above and other advantages of the present disclosure from the following detailed description with reference to the accompanying drawings:

[0007] Figure 1 is an example of a vehicle drawn according to one embodiment of the present disclosure;

[0008] Figure 2 is an example of an off-highway vehicle drawn according to one embodiment of the present disclosure;

[0009] Figure 3A is an example of an off-highway vehicle steering system steering column according to one embodiment of the present disclosure;

[0010] Figure 3B is a detailed example of a steering cylinder for an off-highway vehicle steering system, according to one embodiment of the present disclosure;

[0011] 4A and 4B are views of a steering cylinder of a steering system in the prior art;

[0012] Figure 5Aand 5B This is an example of the prior art where the wheel interferes with the interface between the steering cylinder and the hydraulic hose;

[0013] Figure 6 is included Figure 5A and Figure 5B Prior Art Examples of Systems Example of vehicle turning radius;

[0014] Figure 7A and 7B is an example of a pair of ports for a steering cycle according to one embodiment of the present disclosure;

[0015] Figure 8 According to an embodiment of the present disclosure, Figure 7A and Figure 7B An example of a pair of ports, a pair of wheels turned to a critical position; and

[0016] Figure 9 FIG. 4 is an example of an off-highway vehicle rear axle turning radius plotted according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0017] The following description relates to the driveline system of an off-highway vehicle. Figure 1 is an example of a vehicle according to one embodiment of the present disclosure. Figure 2 is an example of an off-highway vehicle according to one embodiment of the present disclosure. Figure 3A is an example of a steering column for an off-highway vehicle steering system. Figure 3B FIG4 is a cross-sectional view of a steering cylinder according to an embodiment of the present disclosure. Figure 5A and 5B This is an example of prior art interference between the wheels and the ports of the steering cylinder and hydraulic hoses. Figure 6 is included Figure 5A and 5B PRIOR ART EXAMPLES OF SYSTEMS Example of turning radius of a vehicle. Figure 7A and 7B is an example of a pair of ports for a steering cycle according to one embodiment of the present disclosure. Figure 8 A pair of wheels according to one embodiment of the present disclosure are relative to Figure 7A and 7B An example of a position where a pair of ports go to a threshold degree. Figure 9 is an example of an off-highway vehicle rear axle turning radius according to one embodiment of the present disclosure.

[0018] Figure 1-9Configuration examples of various components positioned relative to each other are shown. If elements shown in a figure are in direct contact or directly coupled to each other, then, in at least one example, these elements may be referred to as being in direct contact or directly coupled, respectively. Similarly, in at least one example, elements shown as being adjacent or adjacent to each other may be adjacent or adjacent to each other, respectively. For example, elements in face-to-face contact may be referred to as face-to-face contact elements. As another example, in at least one example, elements placed apart from each other, with only space between them and no other elements, may be referred to as being placed apart from each other. As another example, elements displayed above / below, to the sides of, or to the left / right of each other relative to each other may be referred to as such elements. Furthermore, as shown in the figure, in at least one example, the topmost element or element point may be referred to as the "top" of the element, and the bottommost element or element point may be referred to as the "bottom" of the element. As used herein, up / down, up / down, and up / down may be used to describe the positioning of elements in a figure relative to each other, relative to the vertical axis in the figure. Thus, in one example, an element displayed above other elements is positioned vertically above the other elements. For another example, the shapes of elements depicted in the figures may be referred to as having these shapes (e.g., as circular, straight, flat, curved, rounded, chamfered, beveled, or the like). In addition, in at least one example, elements shown intersecting each other may be referred to as intersecting elements or intersecting each other. In addition, in one example, elements displayed within another element or displayed outside another element may also be referred to as intersecting elements. It is understood that one or more elements referred to as "substantially similar and / or identical" may differ from each other according to manufacturing tolerances (e.g., within a deviation of 1-5%). The term "approximately" as used herein refers to a range of plus or minus five percent, unless otherwise specified. Figure 3B-8 Shown approximately to scale, but other dimensions may be used if desired.

[0019] Now let's see Figure 1 , an off-highway vehicle 100 is shown. Off-highway vehicle 100 includes a powertrain 110. Powertrain 110 includes a prime mover 112 as a power source. Prime mover 112 is connected to a transmission 114 via a drive shaft 116. Drive shaft 116 transmits power from transmission 114 to a differential 118 disposed on a drive axle 102. Differential 118 controls power output to the two halves of drive axle 102, each half being connected to one of a pair of first wheels 104.

[0020] In one example, prime mover 112 is an engine. In another example, prime mover 112 can also be an electric motor. The electric motor can be connected to inverter 124. Inverter 124 can be connected to a battery. In some examples, off-highway vehicle 100 can additionally or alternatively include an engine and an electric motor.

[0021] In one example, the drive axle 102 is a front axle 102, wherein the off-highway vehicle 100 further includes a rear axle 106 coupled to a pair of second wheels 108. The rear axle 106 may be disposed at a second end of the off-highway vehicle opposite the first end where the front axle 102 is disposed.

[0022] Now let's see Figure 2 , Figure 2 An embodiment 200 of an off-highway vehicle 100 is shown. The off-highway vehicle 100 also includes a vehicle chassis 210 to which the front axle 102 and the rear axle 106 are connected. Figure 1 The powertrain 110 in the embodiment may be coupled to the chassis 210 .

[0023] In the embodiment 200 of the off-highway vehicle 100, the forks 214 are positioned at the front end of the off-highway vehicle. Figure 2 In the example of FIG, the off-highway vehicle 100 is a forklift with a forward direction parallel to arrow 290. The off-highway vehicle 100 may further include a steering wheel 212. The steering wheel 212 may be configured to control the rotation of the second pair of wheels 108.

[0024] Now let's see Figure 3A and Figure 3B , which show the steering system of off-highway vehicle 100. The steering system may include a steering wheel 212, a steering column 302, a metering device 304, a hydraulic control valve 306, a hydraulic pump 308, and a steering cylinder 310. Therefore, previously described components may be numbered similarly in this and subsequent figures. In one example, steering wheel 212 may drive steering column 302, which may provide input to metering unit 304. Metering unit 304 may transmit and / or modify the received input and issue a desired turn direction and turn magnitude signal to hydraulic control valve 306. Hydraulic control valve 306 may regulate fluid received from hydraulic pump 308, where the fluid is directed to steering cylinder 310 and used to rotate the pair of second wheels 108. In one example, steering cylinder 310 may be coupled to a pair of steering knuckles 312, each knuckle 312 being associated with a respective wheel of the pair of second wheels 108. In one example, one steering knuckle may drive a first wheel of the pair of second wheels 108, and the other steering knuckle may drive a second wheel of the pair of second wheels 108.

[0025] 4A and 4B, which illustrate a prior art example 400 of a rear axle 402 and a steering cylinder 410. The steering cylinder 410 may include a pair of steering knuckles 412 for controlling the drive of a plurality of wheels 404. FIG4B illustrates a detailed view of the contents within the dashed box 490 in FIG4A.

[0026] The steering cylinder 410 also includes a cylinder tube 414. In one example, the cylinder tube 414 is a housing. The cylinder tube 414 may include a piston 416 disposed therein. One or more seals 418 may be disposed around the piston 416 to retain fluid within a desired area, such as a hydraulic chamber of the cylinder tube 414 through which the piston 416 oscillates. The piston 416 may be coupled to a piston rod 422. Rod seals 424 may be installed at both ends of the cylinder tube 414, namely, in end caps 434.

[0027] A plurality of ports 432 may be provided in an end cap 434 of the hydraulic cylinder tube 414 and configured to transfer fluid from a hydraulic control valve (eg, Figure 3B The fluid is introduced into the interior volume of the cylinder tube 414 via the hydraulic control valve 306 in the piston rod 422. In one example, the fluid is oil. Alternatively, the fluid may be water, alcohol, gas, or the like. Multiple ports 432 receive the fluid through and along the inner surface of an end cap 434 adjacent to the piston rod 422. That is, at the interface between the piston rod 422 and the end cap 434, the multiple ports 432 are fluidically coupled to the hydraulic chamber (e.g., the interior volume of the cylinder tube 414). The fluid can move inward along the length of the piston rod 422, away from the piston rod seal 424 and parallel to the central axis 492, to reach the interior volume. The passageway of the ports 432 can be aligned with the piston rod seal 424 along an axis normal to the central axis 492 of the piston rod 422. In one example, the outboard location of the multiple ports 432 can result in a reduced turning radius for the wheel 404. The cylinder tube 414 and the end cap 434 are sealed by an O-ring 435 between the outer diameter of the end cap 434 and the inner diameter of the cylinder tube 414. The seal prevents the liquid in the cylinder from leaking out, and the half stroke of the cylinder is determined by the distance between the piston face 440 and the end cover face 442.

[0028] The angle 494 at which the plurality of ports 432 are located can be measured relative to a central axis 492. The central axis 492 can be a central axis of the steering cylinder 410 and / or the rear axle 402. In one example, the central axis 492 is a central axis of the piston rod 422. In one example, the angle 494 is 55 degrees.

[0029] Now let's see Figure 5A , which shows a prior art example 500 illustrating a first turning maneuver of rear axle 402 of FIG. 4A and steering cylinder 410 of FIG. As shown, when ports 432 are positioned at angle 494, at least one of wheels 404 may contact one of ports 432 within the range of wheel motion. Consequently, an off-highway vehicle employing a prior art system may have a larger turning radius, requiring a larger space to navigate to a desired location, which may be disadvantageous to the user.

[0030] Now let's see Figure 5B, which shows a prior art example 550 illustrating a steering system having multiple ports 532 at modified angles. As shown, these ports intersect the central axis 590 of the steering cylinder 510. Figure 5B In the embodiment of FIG. 5 , the hydraulic hose 520 fluidly connecting the port to the hydraulic control valve may interfere with and contact one of the wheels 502 during the range of motion of the wheels 502. This may shorten the life of the hose and / or cause leaks.

[0031] Now let's see Figure 6 , Figure 6 An embodiment 600 of a prior art embodiment is shown, illustrating the dimensions of an off-highway vehicle when the wheels are turned to their maximum degree. In one example, the off-highway vehicle is a forklift. In one example, embodiment 600 additionally or alternatively includes a steering cylinder 410 and a wheel 404. Due to the angle of the port and the position of the hose, the maximum steering angle of the wheel can reach 98 degrees. At a steering angle of 98 degrees, a turning radius 608 can reach 1649.95 mm. The wheelbase length 606 of the prior art forklift, from the center axis 492 to the front center axle 602 (on which the front wheels 604 are mounted), is 1450 mm.

[0032] Now let's see Figure 7A and Figure 7B , which illustrate one embodiment 700 of a rear axle 702 according to one example of the present disclosure. Figure 7A and Figure 7B The rear axle 702 may include a steering cylinder 710 , a steering knuckle 712 , and a pair of wheels 704 . The steering cylinder 710 and the steering knuckle 712 may drive the pair of wheels.

[0033] Figure 7B Shown Figure 7A A detailed view 750 of the contents within the dashed box 790 corresponds to components of the steering cylinder 710. The steering cylinder 710 may include a piston 716 disposed within an interior volume 715 of a cylinder tube 714 of the steering cylinder 710. One or more seals 718 may be disposed between the piston 716 and the interior surface of the cylinder tube 714.

[0034] A piston 716 can be disposed on a piston rod 722. A rod seal 724 can be disposed within an end cap 726, wherein the rod seal 724 and the end cap 726 can be configured to retain fluid within the interior volume 715. A plurality of ports 732 can be fluidically coupled to the interior volume 715. The plurality of ports 732 are disposed on a side of the steering cylinder facing the front axle. In one example, the plurality of ports 732 can be positioned more inboard than the plurality of ports 432 in the prior art example shown in FIG. 4B . That is, the plurality of ports 732 can be positioned further away from the pair of wheels 704 than the plurality of ports 432 and the pair of wheels 404 in FIG. 4A and FIG. 4B .

[0035] In one example, each of the plurality of ports 732 may include a first channel 734 and a second channel 736. The first channel 734 may be connected to a hose (eg, Figure 8 The first channel 734 can receive fluid from the hose and direct it in a first direction. This first direction can be angled relative to the axis 792 about which the piston rod 722 and piston 716 oscillate. The second channel 736 can receive fluid from the first channel 734 in a second direction, where the second direction is normal to the first direction and angled relative to the axis 792. The second channel 736 can discharge the fluid into the internal volume at a location spaced from the piston rod 722 and the inner surface of the housing 714. Thus, the first channel 734 is an inlet channel, and the second channel 736 is an outlet channel. In one example, the second channel 736 discharges fluid through a sidewall 738 of the end cap 726. The sidewall 738 can be in normal contact with one or more of the axis 792 and the inner surface of the housing 714. The cylinder tube 714 and the end cap 726 are sealed with an O-ring 735 between the inner diameter of the end cap 726 and the outer diameter of the cylinder tube 714. The seal prevents liquid from leaking from the cylinder, and the half-stroke of the cylinder is determined by the distance between the piston face 740 and the end cap face 742. In this arrangement, because the end cap face 742 is farther away from the piston, the ports 732 can be brought closer together at the same half-stroke value as the prior art example of Figures 4A and 4B. Figure 8 The rotation range is shown in more detail.

[0036] The plurality of ports 732 are arranged inwardly relative to the one or more rod seals 724 of the cylinder tube. Inboard and outboard relate to directions along the axis 792 to and from the wheel to which it is coupled. Inboard is the direction away from the wheel, and outboard is the direction toward the wheel. The distance between adjacent ports of the plurality of ports is less than the length of the interior volume 715. In one example, the distance between each port in the plurality of ports 732 and the nearest wheel of the pair of wheels 704 can be a single fixed distance for each port in the plurality of ports 732.

[0037] Now let's see Figure 8, which shows an embodiment 800 of a pair of wheels 704 turning to a threshold steering angle. In one example, the threshold steering angle is the maximum value of the steering angle range of the pair of wheels 704. Figure 8 In the example, the threshold steering angle is 102 degrees. Figure 6 Compared to the prior art example, under the same steering input, the wheel clears the port and hydraulic hose 802 at the threshold steering angle. Therefore, compared to the prior art, an off-highway vehicle including a steering system consisting of the rear axle 702 and steering cylinder 710 of the present disclosure can reduce the turning radius and allow the off-highway vehicle to make larger turns in a smaller area.

[0038] Now let's see Figure 9 , which shows an embodiment of an off-highway vehicle 900 according to an embodiment of the present disclosure. Figure 6 Compared to the prior art example, due to the more inboard location of the pair of ports 732, the wheels can be turned to a greater threshold steering angle. In one example, the rear wheels 704 can be turned 102 degrees without contacting the ports and / or hoses. At the threshold steering angle, the turning radius 908 can be less than 1630 mm. In one example, the turning radius 908 is 1621.95 mm. Figure 9 The wheelbase length 906 of the mid-lift truck, measured from the axis 792 to the front center axle 902 where the front wheels 904 are located, may be 1450 mm.

[0039] In some examples, the present disclosure also provides support for a steering system that includes a steering cylinder housing a piston rod comprising a piston movable through a hydraulic chamber coupled to a pair of ports, wherein the ports are spaced apart a distance less than a length of the hydraulic chamber.

[0040] The present disclosure provides support for a steering system comprising a hydraulic cylinder configured to adjust a steering angle of a wheel coupled to an axle, and a pair of hydraulic ports, each hydraulic port including an inner portion that sealably engages an outer circumference of a hydraulic cylinder tube. A first example of the steering system further includes the steering system being incorporated into a forklift. A second example of the steering system (optionally including the first example) further includes the axle being a rear axle. A third example of the steering system, optionally including one or more of the foregoing examples, further includes the pair of hydraulic ports not extending into a hydraulic cylinder chamber in which a piston is disposed. A fourth example of the steering system, optionally including one or more of the foregoing examples, further includes the pair of hydraulic ports being directly coupled to an interior volume of the hydraulic cylinder tube, spaced apart from a piston rod coupled to the piston of the hydraulic cylinder tube. A fifth example of the steering system, optionally including one or more of the foregoing examples, further includes an axis parallel to a forward direction of an off-highway vehicle including the steering system, further includes the axis extending through a center of an opening of one of the pair of hydraulic ports and through the interior volume of the hydraulic cylinder tube. A sixth example of a steering system, optionally including one or more of the preceding examples, further includes a distance between openings of the pair of hydraulic ports being less than a length of an interior volume of a hydraulic cylinder tube to which the pair of hydraulic ports are fluidly coupled. A seventh example of a steering system, optionally including one or more of the preceding examples, further includes wherein each hydraulic port of the pair of hydraulic ports includes a first passage and a second passage communicating with the first passage, wherein the second passage directs hydraulic fluid to the interior volume of the hydraulic cylinder tube.

[0041] The present disclosure provides additional support for an off-highway vehicle, including a steering system comprising a steering cylinder disposed on a rear axle of the off-highway vehicle, wherein a valve is fluidically coupled to a plurality of ports of a cylinder tube of the steering cylinder via a hose, wherein the plurality of ports direct fluid away from an interior volume region of a piston rod disposed in the cylinder tube. A first example of the off-highway vehicle further includes each of the plurality of ports comprising an inlet channel and an outlet channel, the outlet channel fluidically connected to the interior volume and angled relative to the inlet channel and each port in the piston rod. A second example of the off-highway vehicle, optionally including the first example, further includes a distance between adjacent ports of the plurality of ports being less than a length of the interior volume. A third example of the off-highway vehicle, optionally including one or more of the preceding examples, further includes the plurality of ports being disposed inwardly relative to one or more rod seals of the hydraulic cylinder tube. A fourth example of the off-highway vehicle, optionally including one or more of the preceding examples, further includes the steering cylinder adjusting a position of a rear wheel coupled to the rear axle via a pair of steering knuckles. A fifth example of an off-highway vehicle (optionally including one or more of the preceding examples) further includes: the off-highway vehicle being a forklift, the forks of the forklift being disposed at an end of the off-highway vehicle opposite the rear axle. A sixth example of an off-highway vehicle (optionally including one or more of the preceding examples) further includes: each of the plurality of ports being spaced a distance from a rear wheel of the rear axle.

[0042] The present disclosure provides further support for a steering system comprising a steering column disposed near a front axle and coupled to a steering wheel, and a steering cylinder disposed on a rear axle and coupled to a hydraulic control valve via a pair of hydraulic cylinder lines, wherein a pair of ports of the steering cylinder are fluidically coupled to the pair of hydraulic cylinder lines and configured to direct fluid from the pair of hydraulic cylinder lines to a hydraulic chamber away from a piston rod and piston. A first example of the steering system further comprises the pair of ports including outlet passages disposed in an end plate and terminating in a sidewall of the end plate, the sidewall being normal to an axis about which the piston rod and piston oscillate. A second example of the steering system (optionally including the first example) further comprises the end plate including a seal in coplanar contact with the piston rod, the seal being located outboard of each pair of ports. A third example of the steering system, optionally including one or more of the foregoing examples, further comprises the steering cylinder, in combination with the steering knuckle, the steering column, and the steering wheel, configured to rotate the pair of rear wheels 102° with a turning radius of less than 1630 mm. A fourth example of a steering system, optionally including one or more of the preceding examples, further includes a pair of ports being arranged on a side of the steering cylinder facing the front axle direction.

[0043] The following claims particularly point out certain combinations and subcombinations regarded as novel and non-obvious. These claims may refer to "an" element or a "first" element or its equivalent. These claims should be understood to include one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amendment of the present claims or by presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, are also deemed included within the subject matter of the present disclosure.

Claims

1. Steering system, characterized in that, include A hydraulic cylinder for adjusting the steering angle of wheels connected to the axle, and a pair of hydraulic ports, wherein each hydraulic port includes an inner portion sealingly engaged with the outer diameter of the hydraulic cylinder tube.

2. The steering system according to claim 1, characterized in that The steering system is included in a forklift.

3. The steering system according to claim 1, characterized in that The axle is a rear axle.

4. The steering system according to claim 1, characterized in that The pair of hydraulic ports do not extend into the hydraulic cylinder cavity in which the piston is disposed.

5. The steering system according to claim 1, characterized in that The pair of hydraulic ports are directly coupled to the interior volume of the hydraulic cylinder tube, spaced apart from a piston rod coupled to a piston of the hydraulic cylinder tube.

6. The steering system according to claim 1, characterized in that The steering system includes an axis parallel to a forward direction of the off-highway vehicle, the axis further comprising: the axis extending through an open center of one of the pair of hydraulic ports and through an interior volume of the hydraulic cylinder tube.

7. The steering system according to claim 1, characterized in that A distance between the pair of hydraulic port openings is less than a length of an interior volume of a hydraulic cylinder tube fluidly coupled to the pair of hydraulic ports.

8. The steering system according to claim 1, wherein: Each of the pair of hydraulic ports includes a first passage and a second passage communicating with the first passage, the second passage directing hydraulic fluid into the interior volume of the cylinder tube.

9. Off-highway vehicle, characterized in that include: The steering system includes a steering cylinder for adjusting the steering angle of wheels connected to an axle, and a pair of hydraulic ports, wherein each hydraulic port includes an inner portion sealingly engaged with the outer circle of a hydraulic cylinder tube.

10. The off-highway vehicle of claim 9, wherein: Each port of the plurality of ports includes an inlet channel and an outlet channel, the outlet channel fluidly coupled to the interior volume and forming an angle with the inlet channel and the piston.

11. The off-highway vehicle of claim 9, wherein: A distance between adjacent ports in the plurality of ports is less than a length of the interior volume.

12. The off-highway vehicle of claim 9, wherein: A plurality of ports are disposed inwardly relative to the one or more rod seals of the cylinder tube.

13. The off-highway vehicle of claim 9, wherein: The steering cylinder adjusts the position of the rear wheels connected to the rear axle through a pair of steering knuckles.

14. The off-highway vehicle of claim 9, wherein: The off-highway vehicle is a forklift, the forks of which are arranged at the other end of the off-highway vehicle relative to the rear axle.

15. The off-highway vehicle of claim 9, wherein: Each of the plurality of ports is spaced a distance from a rear wheel of the rear axle.

Images