Work vehicles
By positioning travel and work control valves in the lower body using solenoid valves and protecting the controller, the work vehicle achieves a compact and functional design with reduced swivel joint and hydraulic piping complexity, enabling features like four-wheel steering.
Patent Information
- Application Number
- JP2022168838
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-10-21
- Publication Date
- 2025-10-15
- Estimated Expiration
- 2042-10-21
AI Technical Summary
Existing work vehicles face challenges in simplifying equipment layout and making the vehicle more compact due to the installation of travel and work control valves in the upper body, which increases the size and complexity of the swivel joint and hydraulic piping, limiting optional features like four-wheel steering.
The work vehicle is configured with travel and work control valves arranged in the lower body using solenoid valves, and a controller is positioned radially inward from the swivel joint, reducing the number of ports and hydraulic piping complexity, and protected from water and damage.
This configuration simplifies the upper body layout, makes it more compact, and enables features like four-wheel steering while minimizing the swivel joint size and hydraulic piping complexity, and protects the controller from water and damage.
Smart Images
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Abstract
Description
[Technical Field]
[0001] The present invention relates to a work vehicle equipped with a hydraulically operated working device. [Background technology]
[0002] Conventionally known examples of work vehicles include excavators and cranes, which have a lower body with tires or crawlers for running attached to a lower frame, an upper body that is rotatably disposed on the lower body, and hydraulically operated working equipment attached to the lower body or upper body.
[0003] With regard to the above-mentioned work vehicle, a configuration is known in which the lower body and upper body are connected via a swivel bearing, and a swivel joint is provided at the connected part to relay hydraulic piping in a rotatable manner (see Patent Document 1: JP 2020-153135 A). [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Japanese Patent Publication No. 2020-153135 Summary of the Invention [Problem to be solved by the invention]
[0005] In the above-mentioned work vehicles, simplifying the equipment layout and making the vehicle more compact are constant challenges. If the travel control valves and work control valves currently installed in the upper body could be installed in the lower body, the equipment mounted on the upper body could be reduced, simplifying the equipment layout in the upper body and making the upper body more compact. However, pilot valves operated by pilot hydraulic pressure have traditionally been used for the travel control valves and work control valves. Therefore, if these valves were installed in the lower body, the number of ports in the swivel joint would increase, resulting in the swivel joint itself becoming larger and the hydraulic piping installed in the lower body becoming larger and more complex. This could also result in a problem of limiting the availability of optional features, such as a four-wheel steering mechanism. [Means for solving the problem]
[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a work vehicle that realizes a configuration in which a travel control valve and a work control valve are arranged in the lower body while suppressing an increase in the number of ports and an increase in size of the swivel joint, and an increase in the number and complexity of the hydraulic piping in the lower body, thereby enabling a simplified equipment layout in the upper body and a more compact upper body.
[0007] The present invention solves the above problems by the means described below.
[0008] The work vehicle according to the present invention is a work vehicle comprising a lower body having a traveling device attached to a lower frame, an upper body rotatably disposed on the lower body via a swivel bearing, and hydraulically operated working equipment attached to the lower body or the upper body, and further comprising one or more traveling control valves for controlling the traveling device and one or more work control valves for controlling the work device, and a swivel joint with a slip ring disposed at a connecting portion between the lower body and the upper body for relaying hydraulic oil and electrical signals, wherein all or part of the traveling control valves and the work control valves are configured using solenoid valves operated by solenoids and are disposed on the lower body, and a controller for controlling the solenoids is provided and fixed to the lower frame. The controller is partly or entirely disposed at a position radially inward from the inner peripheral surface of the swivel bearing and radially outward from the outer peripheral surface of the swivel joint with slip ring. The following are requirements.
[0009] According to the above configuration, it is possible to realize a configuration in which the travel control valve and the work control valve are arranged in the lower body while suppressing an increase in the number of ports and size of the slip-ring swivel joint, and an increase in the number and complexity of the hydraulic piping in the lower body.
[0010] Also This reduces the risk of the controller being submerged in water and the risk of water entering the controller, and also reduces the risk of the controller being damaged by flying stones while driving or by collisions with earth, rocks, wood chips, sawdust, etc. while working.
[0011] Furthermore, it is preferable that the controller be positioned so that its upper end is higher than the upper plate of the lower frame. This configuration further reduces the risk of the controller being submerged in water and the risk of water entering the controller. It also further reduces the risk of the controller being damaged by flying stones while driving or by collisions with earth, rocks, wood chips, sawdust, etc. while working.
[0012] Furthermore, it is preferable that the traveling device has four traveling wheels, two at the front and two at the rear, and that one of the traveling control valves is a steering control valve that switches between steering by any two of the traveling wheels, the front and the rear, and steering by all four wheels, the front and the rear, configured using the solenoid valve and disposed in the lower body. With the above configuration, a highly functional work vehicle can be realized while suppressing the increase in size of the slip ring swivel joint and the increase and complexity of the hydraulic piping provided in the lower body. [Effects of the Invention]
[0013] According to the present invention, it is possible to realize a configuration in which the travel control valve and the work control valve are disposed in the lower body while suppressing an increase in the number and size of the ports of the slip-ring swivel joint and an increase in the size and complexity of the hydraulic piping in the lower body, thereby simplifying the equipment layout in the upper body and making the upper body more compact. [Brief explanation of the drawings]
[0014] [Figure 1] FIG. 1 is a perspective view showing an example of a work vehicle according to an embodiment of the present invention. [Figure 2] Fig. 2A is a perspective view of an upper body of the work vehicle of Fig. 1. Fig. 2B is a side view of a slewing bearing of the work vehicle of Fig. 1. Fig. 2C is a perspective view of a lower body of the work vehicle of Fig. 1. [Figure 3] FIG. 3 is a side cross-sectional view of the connecting portion between the upper body and the lower body. [Figure 4] FIG. 4 is a bottom view of the work vehicle of FIG. [Figure 5] FIG. 5 is an enlarged view of a portion V in FIG. DETAILED DESCRIPTION OF THE INVENTION
[0015] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Fig. 1 is a schematic diagram (perspective view from above the left front) showing an example of a work vehicle 1 according to this embodiment. For ease of explanation, arrows may be used in the drawings to indicate up / down, left / right, and front / rear directions. In addition, in all drawings used to explain the embodiment, members having the same function are given the same reference numerals, and repeated explanations may be omitted.
[0016] First, the overall configuration of the work vehicle 1 will be described. An excavator will be used as an example of the work vehicle 1. However, the work vehicle 1 is not limited to an excavator.
[0017] As shown in FIG. 1, the work vehicle 1 has a lower body 2 with a traveling device 10 attached to a lower frame 28. The work vehicle 1 has an upper body 3 that is disposed on the lower body 2 so as to be able to turn via a slewing bearing 30. The work vehicle 1 has working devices 12, 14 that are attached to the lower body 2 and the upper body 3 and are hydraulically operated. Here, FIG. 2A shows a schematic diagram of the upper body 3 (a perspective view from below the center). FIG. 2B shows a schematic diagram (side view) of the slewing bearing 30. FIG. 2C shows a schematic diagram of the lower body 2 (a perspective view from above the center).
[0018] The swivel bearing 30 includes a lower body-side bearing 30A (which corresponds to the "inner ring" of the bearing in this embodiment) attached to the lower body 2, and an upper body-side bearing 30B (which corresponds to the "outer ring" of the bearing in this embodiment) attached to the upper body 3. In this embodiment, the lower body-side bearing 30A is fixed (by a bolt, for example) to a bearing support part 28B (details of which will be described later) provided on the upper part of the lower body 2. Meanwhile, the upper body-side bearing 30B is fixed (by a bolt, for example) to a bearing fixing part 21 provided on the lower part of the upper body 3. In the swivel bearing 30, the lower body-side bearing 30A and the upper body-side bearing 30B are combined so as to be rotatable relative to each other, with their axes C aligned. The swivel bearing 30 enables the upper body 3 to swivel relative to the lower body 2.
[0019] The lower frame 28 of the lower body 2 includes an upper plate 28A provided at the top and a bearing support portion 28B protruding upward from the upper plate 28A. The upper plate 28A is made of a plate-shaped material and has a flat upper surface 28Aa. The bearing support portion 28B is formed in a generally annular shape with a space in the radial center. The bearing support portion 28B also includes a grease retaining portion 28Ba that retains grease radially inward from the position where the lower body bearing 30A is fixed.
[0020] The upper body 3 is provided with a control room (cabin or canopy) 16 at the front where an operator rides to operate the vehicle and perform tasks. The upper body 3 is provided with a control device 60 that controls the traveling device 10 and the work devices 12, 14 in response to operations by the operator. The upper body 3 is provided with an equipment room 20 at the rear that houses a drive source 18 (an engine in this embodiment). However, the drive source 18 is not limited to an engine. As a variation, the work vehicle 1 may be configured to include a battery-powered electric motor (not shown) instead of or in addition to the engine.
[0021] An example of the traveling device 10 is equipped with four traveling wheels 26, two at the front and two at the back. The traveling wheels 26 have tires 26B fitted around the outer periphery of wheels 26A (there are both single and double types). However, the traveling device 10 is not limited to the traveling wheels 26. As a modified example, the work vehicle 1 may be configured to have caterpillars (crawlers) instead of the traveling wheels 26 (not shown).
[0022] The traveling wheels 26 are driven by a traveling hydraulic motor (not shown). The traveling hydraulic motor is operated by hydraulic pressure. A hydraulic pump (not shown) that generates the hydraulic pressure is disposed in the upper body 3. The hydraulic pump is driven by the drive source 18. In other words, the traveling device 10 operates by receiving pressurized oil delivered from the hydraulic pump.
[0023] The lower body 2 is provided with mudguards 80 that cover the top of each running wheel 26 (see FIG. 5). As an example, the mudguards 80 are formed in a cylindrical shape with an outer circumferential length that is approximately half that of the running wheel 26. Each mudguard 80 is provided with rod-shaped support members 82 at the front and rear, respectively, that are disposed perpendicular to the circumferential direction. The end of the support member 82 on the lower frame 28 side is fixed to a fixing member 84 using a bolt 86. The fixing member 84 is fixed to the axle support portion of the running wheel 26.
[0024] With the above configuration, regardless of the pivot position of the upper body 3 relative to the lower body 2, by loosening the bolts 86, the mudguard 80 can be pulled out horizontally and removed without hitting the upper body 3. This solves the problem that has arisen in conventional work vehicles where the mudguard is attached and detached in the vertical direction, where the mudguard hits the upper body and cannot be removed depending on the pivot position of the upper body.
[0025] An example of the working implement 12 includes a blade 22 and outriggers 24. The blade 22 is attached to the lower body 2 so that it can swing up and down (including forward and backward). The outriggers 24 are attached to the lower body 2 so that they can extend out to the left and right and touch the ground. The blade 22 is driven by a hydraulic cylinder 32. The outriggers 24 are driven by a hydraulic cylinder 34. However, the working implement 12 is not limited to the above configuration.
[0026] An example of the working device 14 includes a boom 42, an arm 44, and an attachment (a bucket in this embodiment) 46. However, the attachment 46 is not limited to a bucket. The boom 42 is attached to the upper body 3 so as to be swingable up and down (including a front-to-rear component). However, the boom 42 is not limited to the above configuration. The boom bracket 48 may be omitted. In this embodiment, the boom bracket 48 is provided between the upper body 3 and the boom 42. The boom bracket 48 enables the boom 42 to swing left and right (including a front-to-rear component) relative to the upper body 3. Note that the boom bracket 48 may be omitted. The arm 44 is attached to the boom 42 so as to be swingable up and down (including a front-to-rear component). The attachment 46 is attached to the arm 44 so as to be swingable up and down (including a front-to-rear component). The boom 42 is driven by a hydraulic cylinder 52. The arm 44 is driven by a hydraulic cylinder 54. The attachment 46 is driven by a hydraulic cylinder 56. However, the working device 14 is not limited to the above configuration.
[0027] Each of the hydraulic cylinders is operated by hydraulic pressure. A hydraulic pump (not shown) that generates the hydraulic pressure is disposed in the upper body 3. The hydraulic pump is driven by a drive source 18. That is, the working devices 12, 14 are operated by receiving pressurized oil delivered from the hydraulic pump.
[0028] It should be noted that other mechanisms for travel and work in the work vehicle 1 according to this embodiment are similar to those of known work vehicles (excavators), and therefore detailed description thereof will be omitted.
[0029] As mentioned above, there is a demand for simplified equipment arrangement and a more compact vehicle, particularly in the upper body 3, of the work vehicle 1. If a configuration can be realized in which the travel control valves and work control valves are disposed in the lower body 2, it will be possible to reduce the amount of equipment mounted on the upper body 3.
[0030] In order to solve the above problems, the work vehicle 1 according to this embodiment has the following configuration.
[0031] The work vehicle 1 is provided with a travel control valve 70A in the lower body 2 that controls the travelling device 10 (one, multiple, or zero depending on the specifications). The work vehicle 1 is provided with a work control valve 70B in the lower body 2 that controls the work device 12 (one, multiple, or zero depending on the specifications). The work vehicle 1 is provided with a work control valve (not shown) in the upper body 3 that controls the work device 14 (one or multiple depending on the specifications).
[0032] With the above configuration, the travel control valve 70A and the work control valve 70B are disposed in the lower body 2. Therefore, it is possible to reduce the amount of equipment mounted on the upper body 3, thereby simplifying the equipment arrangement in the upper body 3 and making the upper body 3 more compact.
[0033] However, conventional work vehicles have often used pilot-operated valves that are operated by pilot hydraulic pressure as travel control valves and work control valves. Therefore, if a travel control valve and a work control valve that are configured as pilot-operated valves are arranged in the lower body 2, the following problems arise. First, the number of ports in the swivel joint increases. Second, the swivel joint becomes larger. Third, the hydraulic piping provided in the lower body 2 increases and becomes more complicated.
[0034] In order to solve the above problems, the work vehicle 1 according to this embodiment has the following configuration: Fig. 3 is a side cross-sectional view of the connecting portion between the upper body 3 and the lower body 2. Fig. 4 is a bottom view of the work vehicle 1.
[0035] The work vehicle 1 is equipped with the following control valves as examples of the travel control valve 70A (these may be omitted depending on the specifications). A steering control valve is provided that switches between steering by any two of the front and rear running wheels 26 and steering by all four wheels, front and rear. This allows for a four-wheel steering mechanism. A speed change control valve is provided that changes the speed of the running hydraulic motor (not shown). A differential lock control valve is provided that switches between locking and unlocking the differential gear (not shown) of the running wheels 26. This allows for a differential lock mechanism. A ram lock control valve is provided that switches between locking and unlocking the ram cylinder (not shown) that oscillates the axle of the running wheels 26. This allows for a ram lock mechanism.
[0036] The work vehicle 1 is equipped with the following control valves as examples of the work control valve 70B (these may be omitted depending on the specifications): A work device control valve is provided that switches between driving the blade 22 and driving the outriggers 24.
[0037] In this embodiment, all (or some) of the travel control valves 70A and the work control valves 70B arranged in the lower body 2 are configured using solenoid valves that are actuated by solenoids. Hereinafter, the control valves configured using the above-mentioned solenoid valves and arranged in the lower body 2 will be distinguished and referred to as control valves 70X.
[0038] In the work vehicle 1, a swivel joint 64 with a slip ring is disposed at the connection between the lower body 2 and the upper body 3. The swivel joint 64 with a slip ring relays hydraulic oil between the hydraulic pump of the upper body 3 and the control valve 70X of the lower body 2.
[0039] Compared to a pilot valve, a solenoid valve can omit pilot hydraulic piping. Therefore, it is possible to solve the problem of an increase in the number of ports of the slip ring swivel joint 64. It is also possible to solve the problem of the slip ring swivel joint 64 becoming larger. It is also possible to solve the problem of the hydraulic piping provided in the lower body 2 becoming larger and more complicated.
[0040] In this way, it is possible to realize a highly functional working vehicle 1 while suppressing an increase in the size of the slip ring swivel joint 64 and an increase in the number and complexity of hydraulic piping provided in the lower body 2.
[0041] Here, if the controller 62 that controls the solenoid of the control valve 70X is provided on the upper body 3, a problem may arise in that the electrical wiring of the slip ring portion of the slip ring swivel joint 64 increases in number and becomes more complicated. On the other hand, if the controller 62 is provided on the lower body 2, a problem may arise in that there is an increased risk of the controller 62 being submerged in water, water entering the controller 62, and damage to the controller due to collision with flying stones, earth and rocks, wood chips, sawdust, etc. while traveling or working.
[0042] In order to solve the above problems, the work vehicle 1 according to this embodiment has the following configuration.
[0043] The controller 62 that controls the solenoid of the control valve 70X is disposed in the lower body 2 (closer to the end of the electrical signal wiring (the control valve 70X side) than the slip ring swivel joint 64). This configuration solves the problem of the electrical wiring of the slip ring part in the slip ring swivel joint 64 becoming increased and complicated.
[0044] The controller 62 is fixed to the lower frame 28 via a stay 66. As an example, the controller 62 is fixed to the bearing support portion 28B of the lower frame 28 (specifically, the underside of the grease holding portion 28Ba) via the stay 66. This configuration can reduce the risk of the controller 62 being submerged in water and the risk of water entering the controller 62. It can also reduce the risk of the controller being damaged by flying stones while traveling or by collisions with earth, rocks, pieces of wood, sawdust, and the like while working.
[0045] In particular, it is preferable that the controller 62 is disposed in a position where a part or all of the controller 62 in the up-down direction is radially inward from the inner peripheral surface of the lower body bearing 30A in a side view and radially outward from the outer peripheral surface of the slip-ring swivel joint 64. This configuration can further reduce the risk of the controller 62 being submerged in water and the risk of water entering the controller 62. It can also further reduce the risk of the controller being damaged by flying stones while traveling or by collisions with earth, rocks, wood chips, sawdust, etc. while working.
[0046] In particular, it is preferable that the upper end 62a of the controller 62 is disposed so that, in a side view, it is higher than the upper plate 28A (specifically, the upper surface 28Aa) of the lower frame 28 that constitutes the lower body 2. This configuration can further reduce the risk of the controller 62 being submerged in water and the risk of water entering the controller 62. It can also further reduce the risk of the controller being damaged by flying stones while traveling or by collisions with earth, rocks, wood chips, sawdust, and the like while working.
[0047] As described above, with the above-described work vehicle 1, it is possible to realize a configuration in which the travel control valve 70A and the work control valve 70B are disposed in the lower body 2 while suppressing an increase in the number of ports and size of the slip ring-equipped swivel joint 64, and an increase in the size and complexity of the hydraulic piping in the lower body 2. This makes it possible to simplify the arrangement of the equipment in the upper body 3 and to make the upper body 3 more compact. It is also possible to achieve high functionality, such as a four-wheel steering mechanism, a differential lock mechanism, a ram lock mechanism, etc.
[0048] The above-described work vehicle 1 can solve the problem of increased and complicated electrical wiring in the slip ring portion of the slip ring swivel joint 64. It also reduces the risk of the controller 62 being submerged in water and the risk of water entering the controller 62. It also reduces the risk of the controller 62 being damaged by flying stones while traveling or by collisions with earth, rocks, wood chips, sawdust, etc. while working.
[0049] The present invention is not limited to the above embodiment (excavator), and can be similarly applied to work vehicles (cranes, aerial work platforms, etc.) in which the upper body rotates relative to the lower body. [Explanation of symbols]
[0050] 1. Work vehicles 2 Lower body 3. Upper body 10 Running gear 12, 14 Work equipment 26 Running wheel 28 Lower Frame 30 slewing bearing 30A Lower body side bearing 30B Upper body side bearing 62 Controller 64 Swivel joint with slip ring 70A, 70X Travel Control Valve 70B, 70X Working Control Valve
Claims
1. A work vehicle comprising: a lower body having a traveling device attached to a lower frame; an upper body rotatably disposed on the lower body via a swivel bearing; and a hydraulically operated working device attached to the lower body or the upper body, one or more travel control valves that control the travel device, and / or one or more work control valves that control the work device; a swivel joint with a slip ring disposed at a connecting portion between the lower body and the upper body and relaying hydraulic oil and electrical signals; All or part of the travel control valve and the work control valve are configured using solenoid valves operated by solenoids and are disposed in the lower body, a controller that controls the solenoid is fixed to the lower frame, The controller is disposed in part or in whole at a position radially inward from the inner peripheral surface of the swivel bearing and radially outward from the outer peripheral surface of the swivel joint with slip ring. A work vehicle characterized by:
2. The controller is arranged so that its upper end is higher than the upper plate of the lower frame.
2. The work vehicle according to claim 1,
3. A work vehicle comprising a lower body with a running device attached to a lower frame, an upper body rotatably disposed on the lower body via a swivel bearing, and a working device attached to the lower body or the upper body and operated by hydraulic pressure, one or more travel control valves that control the travel device, and / or one or more work control valves that control the work device; a swivel joint with a slip ring disposed at a connecting portion between the lower body and the upper body and relaying hydraulic oil and electrical signals; All or part of the travel control valve and the work control valve are configured using solenoid valves operated by solenoids and are disposed in the lower body, a controller that controls the solenoid is fixed to the lower frame, The controller is arranged so that its upper end is higher than the upper plate of the lower frame. A work vehicle characterized by:
4. The traveling device has four traveling wheels, two at the front and two at the rear, As one of the travel control valves, a steering control valve that switches between steering by two of the travel wheels (front and rear) and steering by four wheels (front and rear) is configured using the solenoid valve and is disposed in the lower body. The work vehicle according to any one of claims 1 to 3,
Citation Information
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