Work vehicle

Abstract

To provide a work vehicle in which a cabin is supported by a machine body via a suspension mechanism, the cabin being configured so as to be stopped at a lower limit position (or an upper limit position).SOLUTION: Expansion and contraction of a suspension mechanism allows a stopper member 30 and receiving parts 26c, 29b to touch each other, and with the stopper member 30 compressed, a cabin can be stopped at least at one of a lower limit position and an upper limit position relative to a machine body in the cabin. The stopper member 30 has an inner elastic body 31, and an outer elastic body 32 that is disposed on an outside part of the inner elastic body 31 and connected to the inner elastic body 31, whose degree of hardness is lower than the degree of hardness of the inner elastic body 31, and which touches the receiving parts 26c, 29b.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a work vehicle provided with a cabin that houses a driver's cab in which an operator rides.

Background Art

[0002] In a tractor which is an example of a work vehicle, as disclosed in Patent Document 1, there is a configuration in which a cabin is supported by a machine body via a suspension mechanism. Thereby, even when the work vehicle travels on uneven ground and the machine body vibrates, the vibration of the driver's cab in which the operator rides can be suppressed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the cabin is supported by the machine body via a suspension mechanism and configured to move up and down with respect to the machine body, it is necessary to provide a stopper structure for stopping the cabin at the lower limit position with respect to the machine body or a stopper structure for stopping the cabin at the upper limit position with respect to the machine body.

[0005] An object of the present invention is to configure a work vehicle in which a cabin is supported by a machine body via a suspension mechanism so that the cabin can be stopped with less shock at the lower limit position (upper limit position).

Means for Solving the Problems

[0006] The work vehicle of the present invention comprises a body supported by a running gear, a driver's compartment in which a worker sits, a cabin housing the driver's compartment, a suspension mechanism supporting the cabin on the body, a stopper member provided on one of the body and the cabin, and a receiving portion provided on the other of the body and the cabin. The extension and contraction of the suspension mechanism causes the stopper member and the receiving portion to come into contact, and the stopper member is compressed, thereby stopping the cabin at at least one of the lower limit position of the cabin relative to the body and the upper limit position of the cabin relative to the body. The stopper member comprises an inner elastic body and an outer elastic body disposed on the outer part of the inner elastic body and connected to the inner elastic body, having a hardness lower than that of the inner elastic body and contacting the receiving portion. The outer elastic body has a cross-sectional shape in a plane along the vertical direction of the machine body that is formed in an annular shape surrounding the outer portion of the inner elastic body. It is.

[0007] According to the present invention, when the cabin reaches near its lower limit (upper limit) position due to the contraction of the suspension mechanism, the outer elastic body and the receiving portion of the stopper member come into contact. When the outer elastic body and the receiving portion come into contact, the outer elastic body is mainly compressed because its hardness is lower than that of the inner elastic body, and the movement of the cabin is mainly absorbed by the outer elastic body.

[0008] Once the outer elastic body is sufficiently compressed, the inner elastic body is then primarily compressed. The movement of the cabin is mainly absorbed by the inner elastic body, and because the hardness of the inner elastic body is higher than that of the outer elastic body, the cabin's speed is reduced relatively significantly, causing the cabin to stop at its lower limit (upper limit). As described above, the inner and outer elastic bodies of the stopper member allow the cabin to be stopped with minimal shock at the lower (upper) limit position, thereby improving the ride comfort of the work vehicle.

[0009]

[0010] Also,According to the present invention, the outer elastic body is provided continuously along the outer portion of the inner elastic body. As a result, when the outer elastic body comes into contact with the receiving portion and is compressed, the compressive load on the outer elastic body is distributed, and the movement of the cabin is smoothly absorbed by the outer elastic body, which is advantageous in terms of improving the ride comfort of the work vehicle.

[0011] In the present invention, it is preferable that the stopper member has a cross-section along the vertical direction of the machine body, and that the cross-section is provided so as to be along the left-right direction of the machine body.

[0012] According to the present invention, by providing the stopper member so that its cross-section aligns with the left-right direction of the aircraft, the width of the stopper member in the front-rear direction of the aircraft tends to be reduced, thus simplifying the structure of the stopper member.

[0013] In the present invention, it is preferable that the stopper member has a cross-section along the vertical direction of the machine body, and that the cross-section is provided along the front-rear direction of the machine body.

[0014] According to the present invention, by providing the stopper member so that its cross-section is aligned with the front-rear direction of the aircraft, the width of the stopper member in the left-right direction of the aircraft tends to be reduced, thus simplifying the structure of the stopper member.

[0015] In the present invention, it is preferable that the outer elastic body is provided so as to enclose the outer periphery of the inner elastic body.

[0016] According to the present invention, the outer elastic body is provided so as to enclose the outer periphery of the inner elastic body, thereby providing the outer elastic body continuously over a wide area along the outer part of the inner elastic body. As a result, when the outer elastic body comes into contact with the receiving part and is compressed, the compressive load on the outer elastic body is distributed over a wide area, and the movement of the cabin is smoothly absorbed by the outer elastic body, which is advantageous in terms of improving the ride comfort of the work vehicle.

[0017] This invention The work vehicle comprises a body supported by a running gear, a driver's compartment in which a worker sits, a cabin housing the driver's compartment, a suspension mechanism supporting the cabin to the body, a stopper member provided on one of the body and the cabin, and a stopper member provided on the other of the body and the cabin. Upper limit receiving section and lower limit receiving section A receiving portion having a stopper member and the receiving portion are provided, and as the suspension mechanism expands and contracts, the stopper member and the receiving portion come into contact, and the stopper member is compressed, thereby stopping the cabin at a lower limit position relative to the aircraft body and an upper limit position relative to the aircraft body, the stopper member having an inner elastic body formed in the shape of a disc and an outer elastic body disposed on the outer part of the inner elastic body and connected to the inner elastic body, having a hardness lower than that of the inner elastic body and in contact with the receiving portion, The stopper member has a first elastic portion which is the portion of the outer elastic body facing the lower limit receiving portion and is connected to one of the upper or lower parts of the inner elastic body, and a second elastic portion which is the portion of the outer elastic body facing the upper limit receiving portion and is connected to the other of the upper or lower parts of the inner elastic body. When the suspension mechanism contracts, the first elastic portion and the lower limit receiving portion come into contact, compressing the first elastic portion and the inner elastic body, thereby stopping the cabin at the lower limit position. When the suspension mechanism extends, the second elastic portion and the upper limit receiving portion come into contact, compressing the second elastic portion and the inner elastic body, thereby stopping the cabin at the upper limit position. ru.

[0018] According to the present invention, when the cabin reaches near its lower limit (upper limit) position due to the contraction of the suspension mechanism, the outer elastic body and the receiving portion of the stopper member come into contact. When the outer elastic body and the receiving portion come into contact, the outer elastic body is mainly compressed because its hardness is lower than that of the inner elastic body, and the movement of the cabin is mainly absorbed by the outer elastic body. Once the outer elastic body is sufficiently compressed, the inner elastic body is then primarily compressed. The movement of the cabin is mainly absorbed by the inner elastic body, and because the hardness of the inner elastic body is higher than that of the outer elastic body, the cabin's speed is reduced relatively significantly, causing the cabin to stop at its lower limit (upper limit). As described above, the inner and outer elastic bodies of the stopper member allow the cabin to be stopped with minimal shock at the lower (upper) limit position, thereby improving the ride comfort of the work vehicle. Also, According to the present invention, the receiving portion is provided with an upper limit receiving portion and a lower limit receiving portion. In the stopper member, the first elastic portion, which is the part of the outer elastic body that faces the lower limit receiving portion, is connected to one of the upper and lower parts of the inner elastic body, and the second elastic portion, which is the part of the outer elastic body that faces the upper limit receiving portion, is connected to the other of the upper and lower parts of the inner elastic body.

[0019] According to the present invention, when the cabin approaches the lower limit position due to the contraction of the suspension mechanism, the first elastic portion of the outer elastic body and the lower limit receiving portion come into contact with each other in the stopper member. When the first elastic portion of the outer elastic body and the lower limit receiving portion come into contact, the first elastic portion of the outer elastic body is mainly compressed because the hardness of the first elastic portion of the outer elastic body is lower than that of the inner elastic body, and the movement of the cabin is mainly absorbed by the first elastic portion of the outer elastic body. When the first elastic part of the outer elastic body is sufficiently compressed, next, mainly the inner elastic body is compressed. Since the movement of the cabin is mainly absorbed by the inner elastic body, and the hardness of the inner elastic body is higher than that of the first elastic part of the outer elastic body, the moving speed of the cabin is relatively greatly decelerated and the cabin stops at the lower limit position.

[0020] According to the present invention, when the cabin reaches near the upper limit position due to the extension of the suspension mechanism, in the stopper member, the second elastic part of the outer elastic body and the upper limit receiving part come into contact. When the second elastic part of the outer elastic body and the upper limit receiving part come into contact, since the hardness of the second elastic part of the outer elastic body is lower than that of the inner elastic body, mainly the second elastic part of the outer elastic body is compressed and the movement of the cabin is mainly absorbed by the second elastic part of the outer elastic body. When the second elastic part of the outer elastic body is sufficiently compressed, next, mainly the inner elastic body is compressed. Since the movement of the cabin is mainly absorbed by the inner elastic body, and the hardness of the inner elastic body is higher than that of the second elastic part of the outer elastic body, the moving speed of the cabin is relatively greatly decelerated and the cabin stops at the upper limit position.

[0021] According to the present invention, by the inner elastic body of the stopper member and the first elastic part (the second elastic part of the inner elastic body and the outer elastic body) of the outer elastic body, the cabin can be stopped with less shock at both the lower limit position and the upper limit position, which is advantageous in terms of improving the riding comfort of the work vehicle. According to the present invention, in the stopper member, the inner elastic body, the first elastic part and the second elastic part of the side elastic body are configured as if they are one member. Thereby, the lower limit position and the upper limit position can be determined by one stopper member, and there is no need to separately provide a stopper member for the lower limit position and a stopper member for the upper limit position, so that the structure can be simplified.

[0022]

[0023] Also,According to the present invention, since the inner elastic body is formed in a disc shape, the stopper members are made up of identical members overlapping in the compression direction, making it easier to construct the stopper members to be thin, thus simplifying the structure of the stopper members.

[0024] In the present invention, the outer elastic body is connected over the entire circumference of the outer periphery of the inner elastic body, the portion of the outer elastic body facing the lower limit receiving portion is the first elastic portion, the portion of the outer elastic body facing the upper limit receiving portion is the second elastic portion, and the outer elastic body is compressed along the radial direction of the inner elastic body, and the inner elastic body is compressed.

[0025] According to the present invention, the stopper member has an inner elastic body formed in the shape of a disc, as well as an outer elastic body connected to the entire circumference of the outer periphery of the inner elastic body. Since the functions of the first and second elastic parts are provided in the outer elastic body, it is advantageous in terms of simplifying the structure of the stopper member.

[0026] According to the present invention, in the stopper member, the outer elastic body and the lower limit receiving portion (upper limit receiving portion) come into contact, and the outer elastic body is compressed along the radial direction of the inner elastic body, and the inner elastic body is compressed. As a result, in the outer elastic body, the positions where the lower limit support portion makes contact and the positions where the upper limit support portion makes contact are different from each other, making it possible to easily obtain states in which the first elastic portion of the outer elastic body is compressed and the inner elastic body is compressed, and states in which the second elastic portion of the outer elastic body is compressed and the inner elastic body is compressed.

[0027] In the present invention, a horizontal support portion is provided on the other of the aircraft body and the cabin, and the stopper member is a portion of the outer elastic body facing the horizontal support portion and has a third elastic portion connected to the inner elastic body, and it is preferable that when the cabin moves horizontally with respect to the aircraft body, the third elastic portion and the horizontal support portion come into contact, compressing the third elastic portion and the inner elastic body, thereby stopping the cabin at the horizontal limit position with respect to the aircraft body.

[0028] According to the present invention, when the cabin moves horizontally relative to the aircraft body, the third elastic portion of the outer elastic body and the horizontal receiving portion of the stopper member come into contact. When the third elastic portion of the outer elastic body and the horizontal receiving portion come into contact, the third elastic portion of the outer elastic body is mainly compressed because the hardness of the third elastic portion of the outer elastic body is lower than that of the inner elastic body, and the movement of the cabin is mainly absorbed by the third elastic portion of the outer elastic body. When the third elastic section of the outer elastic body is sufficiently compressed, the inner elastic body is then mainly compressed. The movement of the cabin is mainly absorbed by the inner elastic body, and because the hardness of the inner elastic body is higher than that of the third elastic section of the outer elastic body, the cabin's speed is reduced relatively significantly, causing the cabin to stop at the horizontal limit position.

[0029] According to the present invention, in the initial stage when the cabin moves horizontally relative to the aircraft body, the hardness of the third elastic portion of the outer elastic body is lower than that of the inner elastic body. As a result, the cabin's movement is slowed down relatively little, mainly by the third elastic portion of the outer elastic body, and the cabin's movement is absorbed with little shock. Next, the cabin's movement is slowed down relatively significantly, mainly by the inner elastic body, and the cabin stops at the horizontal limit position. As described above, the inner and outer elastic third elastic parts of the stopper member allow the cabin to be stopped with minimal shock at the horizontal limit position, which is advantageous in terms of improving the ride comfort of the work vehicle.

[0030] In the present invention, the outer elastic body is connected over the entire circumference of the outer periphery of the inner elastic body, the portion of the outer elastic body facing the lower limit receiving portion is the first elastic portion, the portion of the outer elastic body facing the upper limit receiving portion is the second elastic portion, the portion of the outer elastic body facing the horizontal receiving portion is the third elastic portion, and it is preferable that the outer elastic body is compressed along the radial direction of the inner elastic body, and the inner elastic body is compressed.

[0031] According to the present invention, the stopper member has an inner elastic body formed in the shape of a disc, as well as an outer elastic body connected to the entire circumference of the outer periphery of the inner elastic body. The functions of the first elastic part, the second elastic part, and the third elastic part are provided in the outer elastic body, which is advantageous in terms of simplifying the structure of the stopper member.

[0032] According to the present invention, in the stopper member, the outer elastic body and the lower limit receiving portion (upper limit receiving portion, horizontal receiving portion) come into contact, and the outer elastic body is compressed along the radial direction of the inner elastic body, and the inner elastic body is compressed. As a result, in the outer elastic body, the positions where the lower limit support portion, the upper limit support portion, and the horizontal support portion make contact are different from each other, making it possible to easily obtain each of the following states: a state in which the first elastic portion of the outer elastic body is compressed and the inner elastic body is compressed; a state in which the second elastic portion of the outer elastic body is compressed and the inner elastic body is compressed; and a state in which the third elastic portion of the outer elastic body is compressed and the inner elastic body is compressed.

[0033] In the present invention, it is preferable that an intermediate receiving portion is provided between the upper receiving portion and the horizontal receiving portion, the intermediate receiving portion being a part of the upper receiving portion and a part of the horizontal receiving portion, and the portion of the outer elastic body facing the intermediate receiving portion being a part of the portion of the outer elastic body facing the upper receiving portion and a part of the portion of the outer elastic body facing the horizontal receiving portion.

[0034] In work vehicles, it is preferable to stop the cabin rapidly at the upper limit and horizontal limit positions compared to stopping the cabin at the lower limit position, and even if the cabin is stopped rapidly at the upper limit and horizontal limit positions, the impact on ride comfort is minimal.

[0035] According to the present invention, the movement of the cabin is absorbed by the contact between the third elastic part, the upper limit support part, and the intermediate support part. The movement of the cabin is absorbed by the contact between the fourth elastic part, the horizontal support part, and the intermediate support part. As a result, the cabin can be stopped quickly and with little shock at the upper limit position and the horizontal limit position, thereby improving the ride comfort of the work vehicle.

[0036] According to the present invention, the intermediate support portion serves as both the upper support portion and the horizontal support portion, thus simplifying the structure. In the stopper member, the portion of the outer elastic body facing the intermediate receiving portion is used for both the portion of the outer elastic body facing the upper receiving portion and the portion of the outer elastic body facing the horizontal receiving portion, thus simplifying the structure of the stopper member.

[0037] In the present invention, it is preferable that the lower limit receiving portion, the upper limit receiving portion, the horizontal receiving portion, and the intermediate receiving portion are connected, and that the lower limit receiving portion, the upper limit receiving portion, the horizontal receiving portion, and the intermediate receiving portion are arranged to surround the outer circumference of the outer elastic body.

[0038] According to the present invention, since the lower limit support portion, upper limit support portion, horizontal support portion and intermediate support portion are provided so as to surround the outer periphery of the outer elastic body, the lower limit support portion, upper limit support portion, horizontal support portion and intermediate support portion can be expected to provide a function to protect the outer elastic body.

[0039] In the present invention, it is preferable that the width of the inner elastic body in the direction perpendicular to the radial direction and the width of the outer elastic body in the direction perpendicular to the radial direction are the same.

[0040] According to the present invention, when the inner elastic body is compressed after the outer elastic body has been sufficiently compressed, the transition to the compression of the inner elastic body can be made smoothly, which is advantageous in terms of stopping the cabin with less shock and improving the ride comfort of the work vehicle.

[0041] In the present invention, it is preferable that the radial width of the inner elastic body is greater than the radial width of the outer elastic body.

[0042] According to the present invention, since the length in the direction of compression of the inner elastic body is relatively long, it is advantageous in that the movement of the cabin is sufficiently absorbed by the inner elastic body, and it is advantageous in that it improves the ride comfort of the work vehicle while enhancing the function of stopping the cabin.

[0043] In the present invention, it is preferable that the inner elastic body and the outer elastic body are made of urethane.

[0044] According to the present invention, the inner and outer elastic bodies can be simply constructed using urethane, which is advantageous in terms of reducing production costs.

[0045] In the present invention, the outer elastic body is preferably foamed urethane.

[0046] According to the present invention, since the outer elastic body is made of foamed urethane, it is easy to set the hardness of the outer elastic body to be lower than the hardness of the inner elastic body. [Brief explanation of the drawing]

[0047] [Figure 1] This is a left side view of the tractor. [Figure 2] This is a rear view of the tractor. [Figure 3] This is a plan view of the rear of the tractor. [Figure 4] This is a left side view of the area around the left support member and the left stopper member. [Figure 5]This is a rear view of the area around the left support member and the left stopper member. [Figure 6] This is a rear view of the area near the stopper component on the left. [Figure 7] This is a cross-sectional plan view of the stopper member. [Figure 8] This is a rear view of the area around the left support member and the left stopper member in a first alternative embodiment of the invention. [Figure 9] This is a rear view of the area near the left stopper member in a first alternative embodiment of the invention. [Figure 10] This is a left side view of the area near the left support member and the left stopper member in a second alternative embodiment of the invention. [Figure 11] This is a rear view of the area around the left support member and the left stopper member in a second alternative embodiment of the invention. [Figure 12] This is a side view of the stopper member in a third alternative embodiment of the invention. [Modes for carrying out the invention]

[0048] Figures 1 to 12 show a tractor, which is an example of a work vehicle. In Figures 1 to 12, F indicates forward, B indicates backward, U indicates upward, D indicates downward, R indicates right, and L indicates left.

[0049] (Overall configuration of the tractor) As shown in Figure 1, the aircraft body 3 is supported by the right and left front wheels 1 (corresponding to the running gear) and the right and left rear wheels 2 (corresponding to the running gear). The aircraft body 3 includes an engine 4, a clutch housing 5 connected to the rear of the engine 4, a transmission case 6 connected to the rear of the clutch housing 5, a front frame 7 connected to the front of the engine 4, and the like.

[0050] The front wheel 1 is supported by the front frame 7. As shown in Figures 2 and 3, the right and left rear axle cases 19 are connected to the rear of the transmission case 6 (body 3) and are provided to extend laterally outward to the right and left from the rear of the transmission case 6 (body 3), and the rear wheel 2 is supported by the rear axle cases 19.

[0051] As shown in Figure 1, a bonnet 8 is provided at the front of the aircraft body 3, and the engine 4 is covered by the bonnet 8. The driver's compartment 9, where the operator sits, is located at the rear of the aircraft body 3, and the driver's compartment 9 is housed in a cabin 10. The driver's compartment 9 is equipped with a driver's seat 11 and a steering wheel 12 for steering the front wheel 1.

[0052] (Configuration related to the support of the work device) As shown in Figures 1, 2, and 3, a top link 13 and right and left lower links 14 are provided at the rear of the mission case 6 (machine body 3), swinging vertically and extending toward the rear. The top link 13 and lower links 14 constitute a three-point linkage mechanism 18. Working devices such as a rotary tiller (not shown) and a plow (not shown) are connected to and supported by the linkage mechanism 18.

[0053] The PTO shaft 20 is located at the rear of the mission case 6 (machine body 3), and the power from the PTO shaft 20 is transmitted to a working device supported by a link mechanism 18 via a transmission shaft (not shown). Flat plate-shaped right and left cover members 21 are connected to the rear of the mission case 6 (machine body 3), and a cover member 22 is connected across the right and left cover members 21, so that the lateral outward and upward sides of the PTO shaft 20 are covered by the cover members 21 and 22.

[0054] Right and left lift arms 15 are provided on the upper rear of the mission case 6 (aircraft body 3) so as to be able to swing up and down. Right and left lifting cylinders 16 are connected across the lift arms 15 and the cover member 21, and the lifting cylinders 16 are connected to the mission case 6 (aircraft body 3) via the cover member 21.

[0055] A connecting rod 17 is connected between the lift arm 15 and the lower link 14. When the lift arm 15 is raised or lowered by the lifting cylinder 16, the lower link 14 (link mechanism 18) is raised or lowered, and the work device is raised or lowered.

[0056] (Overview of the cabin support structure) As shown in Figures 1, 2, and 3, the front right and left portions of the cabin 10 are supported by the clutch housing 5 (aircraft body 3) by right and left vibration-damping rubbers 23. The rear right portion of the cabin 10 is supported by the aircraft body 3 by the right suspension mechanism 24, and the rear left portion of the cabin 10 is supported by the aircraft body 3 by the left suspension mechanism 24.

[0057] As a result, the rear of the cabin 10 moves up and down relative to the aircraft body 3 by the suspension mechanism 24, with the lower front part of the cabin 10 (vibration-damping rubber 23) acting as a pivot point. Right and left lateral rods 25 are provided as described below to allow vertical movement of the cabin 10 relative to the aircraft body 3 and to restrict lateral movement of the cabin 10 relative to the aircraft body 3.

[0058] The stopper member 30 and the receiving member 29 are provided as described below, and the lower limit position of the cabin 10 relative to the aircraft body 3 and the upper limit position of the cabin 10 relative to the aircraft body 3 are determined by the stopper member 30 and the receiving member 29.

[0059] With the above configuration, the machine is equipped with a body 3 supported by front wheels 1 (running gear) and rear wheels 2 (running gear), an operator's compartment 9 where the operator sits, and a cabin 10 that houses the operator's compartment 9. A suspension mechanism 24 is provided to support the cabin 10 to the machine body 3.

[0060] (Configuration of the suspension mechanism, stopper member, and support member that supports the receiving member) As shown in Figures 1, 2, and 3, right and left support members 26 are provided. As shown in Figures 4 and 5, the support member 26 has a main body portion 26a, a base plate portion 26b, a top plate portion 26c (corresponding to the receiving portion) (corresponding to the lower limit receiving portion), mounting portions 26d, 26e, and reinforcing portion 26f, and the right and left support members 26 are configured to have a symmetrical shape.

[0061] In the support member 26, a flat base plate portion 26b is connected to the lower part of the main body portion 26a, and a flat top plate portion 26c is connected to the upper part of the main body portion 26a. The top plate portion 26c extends rearward from the main body portion 26a, and a reinforcing portion 26f is connected across the main body portion 26a, the base plate portion 26b, and the top plate portion 26c. A mounting portion 26d is connected upward to the rear of the top plate portion 26c, and a mounting portion 26e is connected laterally outward to the main body portion 26a.

[0062] As shown in Figures 1 and 2, right and left fixing members 27 are provided. As shown in Figures 2 and 4, the fixing member 27 has a flat base plate portion 27a and a mounting portion 27b connected to the base plate portion 27a, and the right and left fixing members 27 are configured to be symmetrical with respect to each other.

[0063] The base plate portion 26b of the support member 26 is pressed against the upper surface of the rear axle case 19, and the base plate portion 27a of the fixing member 27 is pressed against the lower surface of the rear axle case 19. Four bolts 28 are attached and tightened across the base plate portion 26b of the support member 26 and the base plate portion 27a of the fixing member 27, thereby attaching the support member 26 and the fixing member 27 to the rear axle case 19.

[0064] As shown in Figures 1, 2, and 3, right and left regulating rods 38 are provided. The right (left) regulating rod 38 is connected to the right (left) lower link 14 (link mechanism 18) and the mounting portion 27b of the right (left) fixing member 27, and the regulating rod 38 restricts the lateral displacement (swing) of the link mechanism 18.

[0065] (Suspension mechanism configuration) As shown in Figures 1, 2, and 3, the right and left frames 39 are connected to the right and left lower parts of the cabin 10 along the front-rear direction, and the right and left frames 33 are connected across the rear right (left) part of the cabin 10 and the rear of the frame 39, so that the frames 39 and 33 are part of the cabin 10. The right and left rear wheel fenders 34 are attached to the frames 39 and 33. The right and left mounting parts 35 are connected to the frame 33 and extend towards the rear.

[0066] The suspension mechanism 24 is composed of a suspension spring 24a and a damper 24b, etc. The right suspension mechanism 24 is connected across the right mounting portion 35 and the mounting portion 26d of the right support member 26. The left suspension mechanism 24 is connected across the left mounting portion 35 and the mounting portion 26d of the left support member 26.

[0067] As shown in Figure 2, the right suspension mechanism 24 is positioned laterally to the right of the right lift arm 15 and the right lifting cylinder 16 when viewed from the rear, and is connected across the right rear part of the cabin 10 and the right rear axle case 19. The lower part of the right suspension mechanism 24 is connected to the rear of the transmission case 6 (body 3) via the right rear axle case 19.

[0068] The left suspension mechanism 24, when viewed from the rear, is positioned laterally to the left relative to the left lift arm 15 and the left lifting cylinder 16, and is connected across the left rear part of the cabin 10 and the left rear axle case 19. The lower part of the left suspension mechanism 24 is connected to the rear of the transmission case 6 (body 3) via the left rear axle case 19.

[0069] (Lateral rod configuration) As shown in Figures 3, 4, and 5, mounting portions 37 are provided on the right and left sides, and these mounting portions 37 are connected to the rear of the frame 39 and extend downward from the frame 39.

[0070] Right and left lateral rods 25 are provided. The right lateral rod 25 is connected across the right mounting portion 37 and the mounting portion 26e of the right support member 26, and is positioned in front of the main body portion 26a of the right support member 26 and the right suspension mechanism 24.

[0071] The left lateral rod 25 is connected across the left mounting portion 37 and the mounting portion 26e of the left support member 26, and is positioned in front of the main body portion 26a of the left support member 26 and the left suspension mechanism 24.

[0072] When no operator is seated in the driver's unit 9, the right and left suspension mechanisms 24 are set to a position where the right and left lateral rods 25 extend diagonally downward to the right and left from the mounting portion 37. When an operator is seated in the driver's unit 9, the suspension mechanisms 24 contract slightly due to the operator's weight, and the right and left lateral rods 25 return to a position close to horizontal.

[0073] In the aforementioned state, when the right (left) rear part of the cabin 10 moves up and down (when the right (left) suspension mechanism 24 extends or retracts), the right (left) lateral rod 25 swings up and down from a near-horizontal position, with the mounting portion 26e of the right (left) support member 26 as the pivot point. As a result, the right (left) lateral rod 25 allows the cabin 10 to move up and down relative to the aircraft body 3, while restricting the lateral movement of the cabin 10 relative to the aircraft body 3.

[0074] (Configuration of stopper component) As shown in Figures 1, 2, and 3, right and left stopper members 30 are provided. As shown in Figures 5, 6, and 7, the stopper member 30 has an inner elastic body 31 and an outer elastic body 32.

[0075] The inner elastic body 31 is integrally formed in a disc shape from urethane, and a recess 31a with a bottom is formed in the center of the inner elastic body 31, and an opening 31b is formed that penetrates from the bottom of the recess 31a to the end of the inner elastic body 31.

[0076] The outer elastic body 32 is integrally formed from urethane (foamed urethane) and connected to the entire circumference of the outer periphery of the inner elastic body 31, forming a ring shape (annular shape). In the inner elastic body 31 and the outer elastic body 32, due to the difference in the degree of polyurethane foaming, the hardness of the outer elastic body 32 is set to be lower than that of the inner elastic body 31, making the outer elastic body 32 softer than the inner elastic body 31. In this case, the hardness of the inner elastic body 31 is preferably 95 to 100 (Type A durometer). The hardness of the outer elastic body 32 is preferably 65 to 90 (Type C durometer).

[0077] The width W11 in the inner elastic body 31 in the direction A1 perpendicular to the radial direction A2 is the same as the width W21 in the outer elastic body 32 in the direction A1 perpendicular to the radial direction A2. In the inner elastic body 31, the width in the radial direction A2 is divided into two parts: the width W12 of the opening 31b of the inner elastic body 31 and the width W13 of the recess 31a of the inner elastic body 31. Widths W12 and W13 are greater than the width W22 of the outer elastic body 32 in the radial direction A2.

[0078] With the above configuration, the stopper member 30 has an inner elastic body 31 and an outer elastic body positioned on the outer part of the inner elastic body 31 and connected to the inner elastic body 31, having a hardness lower than that of the inner elastic body 31 and contacting the receiving portion (the top plate portion 26c of the support member 26 and the upper limit receiving portion 29b of the receiving member 29, which will be described later). The inner elastic body 31 is formed in the shape of a disc. The outer elastic body 32 is connected around the entire circumference of the outer periphery of the inner elastic body 31.

[0079] (Configuration of the support member that supports the stopper member) As shown in Figures 4, 5, and 7, right and left support members 36 are provided. Each support member 36 has a flat base plate portion 36a, a boss portion 36b, and a mounting portion 36c, and the right and left support members 36 are configured to have a symmetrical shape.

[0080] In the support member 36, the base plate portion 36a is formed in a flat plate shape, and a cylindrical boss portion 36b is connected to the front surface of the base plate portion 36a, and the upper part of the base plate portion 36a is bent to form a mounting portion 36c. The mounting portion 36c of the support member 36 is connected to the rear of the frame 39 by bolts so that the base plate portion 36a of the support member 36 is aligned in the vertical and horizontal directions, and the support member 36 is provided above the top plate portion 26c of the support member 26.

[0081] As shown in Figure 7, in the stopper member 30, the collar 40 is inserted from the recess 31a of the inner elastic body 31 into the opening 31b, and the bolt 41 is inserted from the recess 31a of the inner elastic body 31 into the collar 40.

[0082] The stopper member 30 is placed against the rear surface of the base portion 36a of the support member 36, the bolt 41 is inserted into the opening and boss portion 36b of the base portion 36a of the support member 36, a nut 42 is attached to the front end of the bolt 41, and the bolt 41 and nut 42 are tightened. The collar 40 prevents the bolt 41 from being tightened more than necessary, and the inner elastic body 31 will not be crushed due to overtightening of the bolt 41.

[0083] As a result, the inner elastic body 31 is attached to the support member 36 and, via the support member 36, is attached to the cabin 10 (frame 39). The stopper member 30 is attached to the support member 36 and, via the support member 36, is attached to the cabin 10 (frame 39).

[0084] When the right (left) suspension mechanism 24 contracts, causing the right (left) part of the cabin 10 to move up and down relative to the aircraft body 3, the right and left stopper members 30 also move up and down relative to the aircraft body 3 together with the cabin 10.

[0085] With the above configuration, a stopper member 30 is provided on either the aircraft body 3 or the cabin 10. The top plate portion 26c of the support member 26, which is provided below the stopper member 30, serves as the lower limit receiving portion (receiving portion), and the top plate portion 26c (lower limit receiving portion) (receiving portion) of the support member 26 is provided on the aircraft body 3 via the rear axle case 19.

[0086] When the stopper member 30 is attached to the support member 36, the stopper member 30 is located above the top plate portion 26c of the support member 26. The radial direction A2 of the stopper member 30 is aligned with the vertical and horizontal directions, and the direction A1 perpendicular to the radial direction A2 of the stopper member 30 is aligned with the front-to-back direction.

[0087] (Configuration of the receiving member) As shown in Figures 2 and 3, right and left receiving members 29 are provided. As shown in Figures 4, 5, and 6, the receiving member 29 is formed by bending a long, narrow plate, with a mounting portion 29a connected to its lower part, and the right and left receiving members 29 are configured to have a symmetrical shape. The upper part of the receiving member 29 is the upper receiving portion 29b (corresponding to the receiving portion), and the lower part of the receiving member 29 slightly to the side and outside of the upper receiving portion 29b is the intermediate receiving portion 29c.

[0088] The mounting portion 29a of the receiving member 29 is bolted to the top plate portion 26c of the support member 26. The right receiving member 29 is provided to the right and outward relative to the right stopper member 30, and the left receiving member 29 is provided to the left and outward relative to the left stopper member 30.

[0089] (Relationship between stopper member, receiving member and support member) - 1 As shown in Figures 5 and 6, in the stopper member 30, the portion of the outer elastic body 32 that faces the top plate portion 26c (lower limit receiving portion) (receiving portion) of the support member 26 is the first elastic portion 32a, and the first elastic portion 32a is connected to the lower part of the inner elastic body 31.

[0090] In the stopper member 30, the portion of the outer elastic body 32 facing the upper receiving portion 29b (receiving portion) of the receiving member 29 is the second elastic portion 32b, and the portion of the outer elastic body 32 facing the intermediate receiving portion 29c of the receiving member 29 is the second elastic portion 32c. The second elastic portions 32b and 32c are connected to the upper part of the inner elastic body 31. Since the first elastic portion 32a and the second elastic portions 32b and 32c are parts of the outer elastic body 32, the first elastic portion 32a and the second elastic portions 32b and 32c are made of the same material.

[0091] With the above configuration, a stopper member 30 is provided on one of the aircraft body 3 and the cabin 10, and a receiving portion (top plate portion 26c of the support member 26) (upper receiving portion 29b of the receiving member 29) is provided on the other of the aircraft body 3 and the cabin 10. The stopper member 30 has a cross-section 30A (see Figure 5) that is aligned with the vertical direction of the aircraft body 3, and is provided so that the cross-section 30A is aligned with the left-right direction of the aircraft body 3.

[0092] The support structure includes an upper limit support portion (upper limit support portion 29b of the support member 29) and a lower limit support portion (top plate portion 26c of the support member 26). The stopper member 30 has a first elastic portion 32a which is the portion of the outer elastic body 32 that faces the lower limit receiving portion (the top plate portion 26c of the support member 26) and is connected to one of the upper or lower parts of the inner elastic body 31, and a second elastic portion 32b, 32c which is the portion of the outer elastic body 32 that faces the upper limit receiving portion 29b and is connected to the other of the upper or lower parts of the inner elastic body 31.

[0093] An upper limit receiving portion 29b of a receiving member 29 is provided on the other of the aircraft body 3 and cabin 10, and a top plate portion 26c (lower limit receiving portion) of a support member 26 is provided on the other of the aircraft body 3 and cabin 10.

[0094] (Relationship between stopper member, receiving member and support member) - 2 As shown in Figure 6, a gap W31 exists between the first elastic portion 32a of the outer elastic body 32 of the stopper member 30 and the top plate portion 26c (lower limit receiving portion) of the support member 26.

[0095] A gap W32 exists between the second elastic portion 32b of the outer elastic body 32 of the stopper member 30 and the upper limit receiving portion 29b of the receiving member 29. A gap W33 exists between the second elastic portion 32c of the outer elastic body 32 of the stopper member 30 and the intermediate receiving portion 29c of the receiving member 29.

[0096] When the cabin 10 descends relative to the aircraft body 3 due to the contraction of the suspension mechanism 24, there is a lower limit restriction state in which the first elastic portion 32a of the outer elastic body 32 of the stopper member 30 and the top plate portion 26c (lower limit receiving portion) of the support member 26 come into contact, as described below.

[0097] When the cabin 10 rises relative to the aircraft body 3 due to the extension of the suspension mechanism 24, there is an upper limit restriction state in which the second elastic parts 32b and 32c of the outer elastic body 32 of the stopper member 30 come into contact with the upper limit receiving part 29b and the intermediate receiving part 29c of the receiving member 29, as described below.

[0098] With the operator seated in the driver's unit 9 (in a nearly horizontal position), intervals W31, W32, and W33 are approximately the same. As a result, the lower limit restriction state and the upper limit restriction state occur with approximately the same frequency.

[0099] (The cabin is stopped by a stopper member at its lowest position relative to the aircraft) - 1 As shown in Figures 4, 5, and 6, when the right (left) suspension mechanism 24 contracts and the right (left) part of the cabin 10 descends relative to the aircraft body 3, the first elastic portion 32a of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the top plate portion 26c (lower limit receiving portion) of the right (left) support member 26.

[0100] As the cabin 10 descends further relative to the aircraft body 3, the first elastic portion 32a of the outer elastic body 32 is compressed in the stopper member 30 because the hardness of the outer elastic body 32 is lower than that of the inner elastic body 31 (the outer elastic body 32 is softer than the inner elastic body 31). As a result, the descent of the cabin 10 is absorbed mainly by the first elastic portion 32a of the outer elastic body 32.

[0101] (The cabin is stopped by a stopper member at its lowest position relative to the aircraft) - 2 As shown in Figures 4, 5, and 6, when the cabin 10 descends further relative to the aircraft body 3 and the first elastic portion 32a of the outer elastic body 32 is sufficiently compressed in the stopper member 30, the lower part of the inner elastic body 31 is then mainly compressed. As a result, the descent of the cabin 10 is mainly absorbed by the lower part of the inner elastic body 31.

[0102] In this case, in the stopper member 30, the hardness of the inner elastic body 31 is higher than that of the outer elastic body 32 (the inner elastic body 31 is harder than the outer elastic body 32), which causes a relatively large reduction in the downward speed of the cabin 10.

[0103] As shown in Figure 7, in the stopper member 30, the width W11 of the inner elastic body 31 in the direction A1 perpendicular to the radial direction A2 is the same as the width W21 of the outer elastic body 32 in the direction A1 perpendicular to the radial direction A2. As a result, in the stopper member 30, the first elastic portion 32a of the outer elastic body 32 is sufficiently compressed before the compression of the lower part of the inner elastic body 31 proceeds smoothly, and the downward movement of the cabin 10 is absorbed smoothly.

[0104] As shown in Figures 4, 5, and 6, in the stopper member 30, the lower part of the inner elastic body 31 is compressed, which significantly reduces the downward speed of the cabin 10, causing the cabin 10 to stop at the lower limit position.

[0105] (The cabin is stopped by a stopper member at its lowest position relative to the aircraft) - 3 With the above configuration, the extension and contraction of the suspension mechanism 24 causes the stopper member 30 to come into contact with the receiving portion (the top plate portion 26c of the support member 26) (the upper receiving portion 29b of the receiving member 29), and the stopper member 30 is compressed, thereby stopping the cabin 10 at at least one of the lower limit position of the cabin 10 relative to the aircraft body 3 and the upper limit position of the cabin 10 relative to the aircraft body 3.

[0106] As the suspension mechanism 24 contracts, the first elastic part 32a comes into contact with the lower limit receiving part (the top plate part 26c of the support member 26), compressing the first elastic part 32a and the inner elastic body 31, thereby stopping the cabin 10 at the lower limit position. In the stopper member 30, the outer elastic body 32 is compressed along the radial direction A2 of the inner elastic body 31, and the inner elastic body 31 is compressed.

[0107] (The cabin is stopped by a stopper member at its upper limit relative to the aircraft) - 1 As shown in Figures 4, 5, and 6, when the right (left) suspension mechanism 24 extends and the right (left) part of the cabin 10 rises relative to the aircraft body 3, the second elastic portion 32b of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the upper limit receiving portion 29b of the right (left) receiving member 29. Almost simultaneously, the second elastic portion 32c of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the intermediate receiving portion 29c of the right (left) receiving member 29.

[0108] As the cabin 10 rises further relative to the aircraft body 3, the stopper member 30 is compressed mainly by the second elastic portions 32b and 32c of the outer elastic body 32 because the hardness of the outer elastic body 32 is lower than that of the inner elastic body 31 (the outer elastic body 32 is softer than the inner elastic body 31). As a result, the rise of the cabin 10 is absorbed mainly by the second elastic portions 32b and 32c of the outer elastic body 32.

[0109] (The cabin is stopped by a stopper member at its upper limit relative to the aircraft) - 2 As shown in Figures 4, 5, and 6, when the cabin 10 rises further relative to the aircraft body 3 and the second elastic portions 32b and 32c of the outer elastic body 32 are sufficiently compressed in the stopper member 30, the upper part and the adjacent parts to the upper part of the inner elastic body 31 are then mainly compressed. As a result, the rise of the cabin 10 is absorbed mainly by the upper part and the adjacent parts to the upper part of the inner elastic body 31.

[0110] In this case, in the stopper member 30, the hardness of the inner elastic body 31 is higher than that of the outer elastic body 32 (the inner elastic body 31 is harder than the outer elastic body 32), which causes a relatively large reduction in the upward speed of the cabin 10.

[0111] As shown in Figure 7, in the stopper member 30, the width W11 of the inner elastic body 31 in the direction A1 perpendicular to the radial direction A2 is the same as the width W21 of the outer elastic body 32 in the direction A1 perpendicular to the radial direction A2. As a result, in the stopper member 30, the compression of the second elastic parts 32b and 32c of the outer elastic body 32 is sufficiently accelerated, and then the compression of the upper part and the adjacent part to the upper part of the inner elastic body 31 is smoothly accelerated, resulting in smooth absorption of the rise of the cabin 10.

[0112] As shown in Figures 4, 5, and 6, in the stopper member 30, the upper part and the lateral part adjacent to the upper part of the inner elastic body 31 are compressed, which significantly reduces the upward speed of the cabin 10, causing the cabin 10 to stop at the upper limit position.

[0113] In the stopper member 30, the cabin 10 rapidly stops at the upper limit position due to the compression of the second elastic portions 32b and 32c of the outer elastic body 32, and the compression of the upper part and the adjacent part to the upper part of the inner elastic body 31.

[0114] (The cabin is stopped by a stopper member at its upper limit relative to the aircraft) - 3 With the above configuration, as the suspension mechanism extends, the second elastic parts 32b and 32c come into contact with the upper limit receiving part 29b, compressing the second elastic parts 32b and 32c and the inner elastic body 31, thereby stopping the cabin 10 at the upper limit position.

[0115] In this case, in addition to the second elastic portion 32b of the outer elastic body 32, the second elastic portion 32c of the outer elastic body 32 and the intermediate receiving portion 29c of the receiving member 29 come into contact, compressing the second elastic portion 32c of the outer elastic body 32 and the inner elastic body 31, thereby stopping the cabin 10 at the upper limit position. In the stopper member 30, the outer elastic body 32 is compressed along the radial direction A2 of the inner elastic body 31, and the inner elastic body 31 is compressed.

[0116] (Configuration of the receiving member and stopper member in the first alternative embodiment of the invention) - 1 In the configurations shown in Figures 1 to 7, the right and left lateral rods 25 may be eliminated, and configurations in which the lateral rods 25 are eliminated are shown in Figures 8 and 9.

[0117] As shown in Figures 8 and 9, when the lateral rod 25 is eliminated, the mounting portion 37 becomes unnecessary, and the mounting portion 26e of the support member 26 (see Figures 4 and 5) also becomes unnecessary. In the receiving member 29, in addition to the upper receiving portion 29b and the intermediate receiving portion 29c, the portion between the mounting portion 29a and the intermediate receiving portion 29c becomes the horizontal receiving portion 29d. The intermediate receiving portion 29c of the receiving member 29 also serves as the upper receiving portion 29b and the horizontal receiving portion 29d of the receiving member 29. As a result, the receiving member 29 is provided with multiple upper receiving portions 29b (intermediate receiving portions 29c) and multiple horizontal receiving portions 29d (intermediate receiving portions 29c).

[0118] In the outer elastic body 32 of the stopper member 30, in addition to the first elastic portion 32a and the second elastic portions 32b and 32c, the portion facing the horizontal receiving portion 29d of the receiving member 29 becomes the third elastic portion 32d, and the third elastic portion 32d is connected to the lateral portion of the inner elastic body 31.

[0119] In this case, in the outer elastic body 32 of the stopper member 30, the second elastic portion 32c also becomes the third elastic portion 32d. Since the first elastic portion 32a, the second elastic portions 32b, 32c and the third elastic portion 32d are parts of the outer elastic body 32, the first elastic portion 32a, the second elastic portions 32b, 32c and the third elastic portion 32d are made of the same material.

[0120] A gap W34 exists between the third elastic portion 32d of the outer elastic body 32 of the stopper member 30 and the horizontal receiving portion 29d of the receiving member 29. When an operator is seated in the driver's unit 9, gaps W31, W32, and W33 are approximately the same, and gaps W31, W32, W33 and W34 are also approximately the same.

[0121] (Configuration of the receiving member and stopper member in the first alternative embodiment of the invention) - 2 With the above configuration, a horizontal receiving portion 29d of the receiving member 29 is provided on the other of the aircraft body 3 and the cabin 10. The intermediate receiving portion 29c of the receiving member 29 also becomes a horizontal receiving portion 29d, and multiple horizontal receiving portions 29d (intermediate receiving portions 29c) are provided.

[0122] The stopper member 30 is the portion of the outer elastic body 32 that faces the horizontal receiving portion 29d, and has a third elastic portion 32d connected to the inner elastic body 31. The portion of the outer elastic body 32 that faces the lower limit receiving portion (the top plate portion 26c of the support member 26) is the first elastic portion 32a, the portion of the outer elastic body 32 that faces the upper limit receiving portion 29b is the second elastic portion 32b, and the portion of the outer elastic body 32 that faces the horizontal receiving portion 29d is the third elastic portion 32d. In the outer elastic body 32 of the stopper member 30, the second elastic portion 32c also becomes the third elastic portion 32d, so there are multiple third elastic portions 32d (second elastic portions 32c).

[0123] In the support member 26 and the receiving member 29, the top plate portion 26c (lower limit receiving portion), the upper limit receiving portion 29b, the horizontal receiving portion 29d, and the intermediate receiving portion 29c are connected. The top plate portion 26c (lower limit receiving portion), the upper limit receiving portion 29b, the horizontal receiving portion 29d, and the intermediate receiving portion 29c are provided so as to surround the outer circumference of the outer elastic body 32 of the stopper member 30.

[0124] In the configurations shown in Figures 8 and 9, the state in which the cabin 10 is stopped at the lower and upper limits relative to the aircraft body 3 by the contraction and extension of the suspension mechanism 24 is the same as in the configurations shown in Figures 1 to 7. The receiving member 29 and the stopper member 30 stop the cabin 10 at the horizontal limit position in the left-right direction relative to the aircraft body 3 as described below.

[0125] (In a first alternative embodiment of the invention, the cabin is positioned at the horizontal limit position in the left-right direction relative to the aircraft body by a stopper member) - 1 As shown in Figures 8 and 9, when the cabin 10 moves horizontally to the aircraft body 3, the third elastic portion 32d of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the horizontal receiving portion 29d of the right (left) receiving member 29. Almost simultaneously, the second elastic portion 32c of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the intermediate receiving portion 29c of the right (left) receiving member 29.

[0126] As the cabin 10 moves further in the left-right direction relative to the aircraft body 3, the stopper member 30 is compressed mainly by the third elastic portion 32d and the second elastic portion 32c of the outer elastic portion 32 because the hardness of the outer elastic portion 32 is lower than that of the inner elastic portion 31 (the outer elastic portion 32 is softer than the inner elastic portion 31). As a result, the left-right movement of the cabin 10 is absorbed mainly by the third elastic portion 32d and the second elastic portion 32c of the outer elastic portion 32.

[0127] (In a first alternative embodiment of the invention, the cabin is positioned at the horizontal limit position in the left-right direction relative to the aircraft body by a stopper member) - 2 As shown in Figures 8 and 9, when the cabin 10 moves further in the left-right direction relative to the aircraft body 3, and the third elastic portion 32d and the second elastic portion 32c of the outer elastic body 32 are sufficiently compressed in the stopper member 30, then the right portion and the portion adjacent to the right portion (the left portion and the portion adjacent to the left portion) of the inner elastic body 31 are mainly compressed. As a result, the left-right movement of the cabin 10 is mainly absorbed by the right portion and the portion adjacent to the right portion (the left portion and the portion adjacent to the left portion) of the inner elastic body 31.

[0128] In this case, in the stopper member 30, the hardness of the inner elastic body 31 is higher than that of the outer elastic body 32 (the inner elastic body 31 is harder than the outer elastic body 32), which causes a relatively large reduction in the lateral movement speed of the cabin 10.

[0129] As shown in Figure 7, in the stopper member 30, the width W11 of the inner elastic body 31 in the direction A1 perpendicular to the radial direction A2 is the same as the width W21 of the outer elastic body 32 in the direction A1 perpendicular to the radial direction A2. As a result, in the stopper member 30, the compression of the inner elastic body 31 smoothly progresses from the third elastic portion 32d and the second elastic portion 32c of the outer elastic body 32 being sufficiently compressed to the right portion and the portion adjacent to the right portion (the left portion and the portion adjacent to the left portion), thereby smoothly absorbing the lateral movement of the cabin 10.

[0130] As shown in Figures 8 and 9, in the stopper member 30, the right portion of the inner elastic body 31 and the portion adjacent to the right portion (the left portion and the portion adjacent to the left portion) are compressed, which significantly reduces the lateral movement speed of the cabin 10, causing the cabin 10 to stop at the horizontal limit position in the lateral direction.

[0131] In the stopper member 30, the cabin 10 rapidly stops at the horizontal limit position in the left-right direction due to the compression of the third elastic portion 32d and the second elastic portion 32c of the outer elastic body 32, and the compression of the right portion and the portion adjacent to the right portion (left portion and the portion adjacent to the left portion) of the inner elastic body 31.

[0132] (In a first alternative embodiment of the invention, the cabin is positioned at the horizontal limit position in the left-right direction relative to the aircraft body by a stopper member) - 3 With the above configuration, when the cabin 10 moves horizontally relative to the aircraft body 3, the third elastic part 32d and the horizontal receiving part 29d come into contact, compressing the third elastic part 32d and the inner elastic body 31, thereby stopping the cabin 10 at the horizontal limit position relative to the aircraft body 3.

[0133] In this case, in addition to the third elastic portion 32d of the outer elastic body 32, the second elastic portion 32c of the outer elastic body 32 and the intermediate receiving portion 29c of the receiving member 29 come into contact, compressing the second elastic portion 32c of the outer elastic body 32 and the inner elastic body 31, thereby stopping the cabin 10 at the horizontal limit position relative to the aircraft body 3. In the stopper member 30, the outer elastic body 32 is compressed along the radial direction A2 of the inner elastic body 31 and the outer elastic body 32, and the inner elastic body 31 is compressed.

[0134] The receiving member 29 is provided with an intermediate receiving portion 29c located between the upper receiving portion 29b and the horizontal receiving portion 29d. The intermediate receiving portion 29c is a part of the upper receiving portion 29b and a part of the horizontal receiving portion 29d.

[0135] In the stopper member 30, the portion of the outer elastic body 32 facing the intermediate receiving portion 29c of the receiving member 29 (second elastic portion 32c) is part of the portion of the outer elastic body 32 facing the upper limit receiving portion 29b of the receiving member 29, and is also part of the portion of the outer elastic body 32 facing the horizontal receiving portion 29d of the receiving member 29.

[0136] (Configuration of the receiving member and stopper member in a second alternative embodiment of the invention) As shown in Figures 10 and 11, the right and left stopper members 30 (inner elastic body 31 and outer elastic body 32) may be configured to be supported by the right and left frames 39 such that their radial direction A2 (see Figure 7) is aligned with the vertical and longitudinal directions. In this case, the right and left receiving members 29 are configured as shown in Figures 10 and 11, and the right and left lateral rods 25 shown in Figures 1 to 7 are used as is.

[0137] As shown in Figures 10 and 11, the mounting portion 36c of the support member 36 is connected to the rear of the frame 39 by bolts so that the base portion 36a of the support member 36 is aligned in the vertical and front-rear directions. The stopper member 30 is attached to the base portion 36a of the support member 36 by collar 40, bolt 41 and nut 42, similar to the structure shown in Figures 1 to 7, and the radial direction A2 (see Figure 7) of the stopper member 30 (inner elastic body 31 and outer elastic body 32) is aligned in the vertical and front-rear directions.

[0138] The receiving member 29 is formed by bending a long, narrow plate into an arch shape, with mounting portions 29a connected to the lower front and lower rear portions, and the front and rear mounting portions 29a are bolted to the top plate portion 26c of the support member 26.

[0139] In the receiving member 29, the upper part is the upper receiving portion 29b, the parts connected to the mounting portion 29a are the horizontal receiving portions 29d and 29f, and the parts between the upper receiving portion 29b and the horizontal receiving portions 29d and 29f are the intermediate receiving portions 29c and 29e.

[0140] In the stopper member 30, the portion of the outer elastic body 32 facing the top plate portion 26c (lower limit receiving portion) of the support member 26 is the first elastic portion 32a. The portion of the outer elastic body 32 facing the upper limit receiving portion 29b of the receiving member 29 is the second elastic portion 32b. The portions of the outer elastic body 32 facing the intermediate receiving portions 29c and 29e of the receiving member 29 are the second elastic portions 32c and 32e. The portions of the outer elastic body 32 facing the horizontal receiving portions 29d and 29f of the receiving member 29 are the third elastic portions 32d and 32f.

[0141] With the above configuration, the stopper member 30 has a cross-section 30A (see Figure 10) that is aligned with the vertical direction of the aircraft body 3, and the cross-section 30A is provided to be aligned with the front-rear direction of the aircraft body 3. The receiving member 29 and stopper member 30 shown in Figures 10 and 11 allow the cabin 10 to be stopped at the lower limit position, the upper limit position, and the horizontal limit position in the longitudinal direction relative to the aircraft body 3, as described below.

[0142] (In a second alternative embodiment of the invention, the cabin is stopped by stopper members at the lower and upper limits relative to the aircraft body.) The state in which the cabin 10 is stopped at the lower limit position relative to the aircraft body 3 due to the contraction of the suspension mechanism 24 is the same as the configuration shown in Figures 1 to 7.

[0143] As shown in Figures 10 and 11, when the right (left) suspension mechanism 24 extends and the right (left) part of the cabin 10 rises relative to the aircraft body 3, the second elastic part 32b of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the upper receiving part 29b of the right (left) receiving member 29. Almost simultaneously, the second elastic parts 32c, 32e of the outer elastic body 32 of the right (left) stopper member 30 come into contact with the intermediate receiving parts 29c, 29e of the right (left) receiving member 29.

[0144] As the cabin 10 rises further relative to the aircraft body 3, the stopper member 30 compresses mainly the second elastic portions 32b, 32c, and 32e of the outer elastic body 32, and then mainly the upper part and the portions adjacent to the front and rear of the upper part of the inner elastic body 31. In the stopper member 30, the cabin 10 stops at the upper limit position as the upper part of the inner elastic body 31 and the parts adjacent to the front and rear of the upper part are compressed.

[0145] In the stopper member 30, the cabin 10 rapidly stops at the upper limit position due to the compression of the second elastic portions 32b, 32c, and 32e of the outer elastic body 32, and the compression of the upper part and the portions adjacent to the front and rear of the upper part of the inner elastic body 31.

[0146] (In a second alternative embodiment of the invention, the cabin is stopped by a stopper member at the forward horizontal limit position relative to the aircraft body.) As shown in Figures 10 and 11, when the cabin 10 moves forward in a horizontal direction relative to the aircraft body 3, the third elastic portion 32d of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the horizontal receiving portion 29d of the right (left) receiving member 29. Almost simultaneously, the second elastic portion 32c of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the intermediate receiving portion 29c of the right (left) receiving member 29.

[0147] As the cabin 10 moves further forward relative to the aircraft body 3, the stopper member 30 is compressed, primarily by the third elastic portion 32d and the second elastic portion 32c of the outer elastic body 32, and then primarily by the front portion and the portion adjacent to the front portion of the inner elastic body 31. In the stopper member 30, the front portion and the portion adjacent to the front portion of the inner elastic body 31 are compressed, causing the cabin 10 to stop at the front horizontal limit position.

[0148] In the stopper member 30, the cabin 10 rapidly stops at the front horizontal limit position due to the compression of the third elastic portion 32d and the second elastic portion 32c of the outer elastic body 32, and the compression of the front portion and the portion adjacent to the front portion of the inner elastic body 31.

[0149] (In a second alternative embodiment of the invention, the cabin is stopped by a stopper member at the rear horizontal limit position relative to the aircraft body.) As shown in Figures 10 and 11, when the cabin 10 moves backward in a horizontal direction relative to the aircraft body 3, the third elastic portion 32f of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the horizontal receiving portion 29f of the right (left) receiving member 29. Almost simultaneously, the second elastic portion 32e of the outer elastic body 32 of the right (left) stopper member 30 comes into contact with the intermediate receiving portion 29e of the right (left) receiving member 29.

[0150] As the cabin 10 moves further rearward relative to the aircraft body 3, the stopper member 30 is compressed primarily by the third elastic portion 32f and the second elastic portion 32e of the outer elastic body 32, and then primarily by the rear portion and the portion adjacent to the rear portion of the inner elastic body 31. In the stopper member 30, the rear portion and the portion adjacent to the rear portion of the inner elastic body 31 are compressed, causing the cabin 10 to stop at the rear horizontal limit position.

[0151] In the stopper member 30, the cabin 10 rapidly stops at the rear horizontal limit position due to the compression of the third elastic portion 32f and the second elastic portion 32e of the outer elastic body 32, and the compression of the rear portion and the portion adjacent to the rear portion of the inner elastic body 31.

[0152] (Third alternative form of the invention) As shown in Figure 12, the stopper member 30 may be configured in an elongated ellipse shape rather than a circular shape. In this case, the stopper member 30 (inner elastic body 31 and outer elastic body 32) may be formed in a tapered shape towards the outside in the radial direction A2 (see Figure 7). As a result, the cross-sectional area of ​​the stopper member 30 (inner elastic body 31 and outer elastic body 32) on a plane perpendicular to the radial direction A2 becomes smaller towards the outside.

[0153] According to the above configuration, the first elastic portion 32a and the second elastic portion 32b of the outer elastic body 32 are separate entities. The first elastic portion 32a of the outer elastic body 32 is connected to one of the upper or lower parts of the inner elastic body 31, and the second elastic portion 32b of the outer elastic body 32 is connected to the other of the upper or lower parts of the inner elastic body 31. In the outer elastic body 32, the hardness of the first elastic portion 32a and the hardness of the second elastic portion 32b may be set to be different. Third elastic portions 32d and 32f may be provided in the lateral portion between the first elastic portion 32a and the second elastic portion 32b.

[0154] (Fourth alternative embodiment of the invention) The system may be configured so that an operator can slightly loosen the bolt 41, rotate the stopper member 30 slightly relative to the support member 36 (bolt 41), and then tighten the bolt 41 again to change the phase (angle) of the stopper member 30 relative to the support member 36.

[0155] According to the above-described configuration, in the configurations shown in Figures 1 to 7, (First Alternative Embodiment of the Invention), and (Second Alternative Embodiment of the Invention), for example, if the first elastic portion 32a of the outer elastic body 32 of the stopper member 30 deteriorates, the phase (angle) of the stopper member 30 with respect to the support member 36 is changed, thereby setting another part of the outer elastic body 32 as a new first elastic portion 32a.

[0156] According to the above configuration, in the third alternative embodiment of the invention, the stopper member 30 is inverted vertically, so that the first elastic portion 32a of the outer elastic body 32 becomes the second elastic portion 32b, and the second elastic portion 32b of the outer elastic body 32 becomes the first elastic portion 32a.

[0157] (Fifth alternative embodiment of the invention) In the first alternative embodiment of the invention, the receiving member 29 may be configured in an arch shape as shown in Figures 10 and 11.

[0158] (Sixth alternative embodiment of the invention) In the stopper member 30, the outer circumference of the outer elastic body 32 may be provided with a number of outwardly oriented protrusions (not shown) along the radial direction A2 (see Figure 7), so that the stopper member 30 can be configured in a star shape or a gear shape. In this case, multiple protrusions are provided on the outer circumference of the annular outer elastic body 32, and each of the protrusions of the outer elastic body 32 becomes the first elastic portion 32a, the second elastic portions 32c, 32e, and the third elastic portions 32d, 32f.

[0159] (Seventh alternative embodiment of the invention) In the configurations shown in Figures 1 to 7, and in (First Alternative Embodiment of the Invention) to (Sixth Alternative Embodiment of the Invention), the receiving member 29 may be formed in an arc shape and arranged concentrically with the stopper member 30.

[0160] (Eighth alternative form of the invention) The stopper member 30 (inner elastic body 31 and outer elastic body 32) may be attached to the support member 26, and the receiving member 29 may be attached to the frames 39 and 33.

[0161] According to the above configuration, the receiving member 29 is provided on the cabin 10 (frames 39, 33), and the stopper member 30 (inner elastic body 31 and outer elastic body 32) is provided on the machine body 3 via the support member 26 and the rear axle case 19. In the stopper member 30, the upper part of the outer elastic body 32 becomes the first elastic portion 32a, and the lower part of the outer elastic body 32 becomes the second elastic portion 32b. In the receiving member 29, the upper limit receiving portion 29b becomes the lower limit receiving portion, and a new upper limit receiving portion is provided that faces the lower part (second elastic portion 32b) of the outer elastic body 32.

[0162] (Ninth alternative embodiment of the invention) In the stopper member 30, an elastic body (not shown) other than the inner elastic body 31 and the outer elastic body 32 may be provided in at least one of the following portions: the outer surface portion of the outer elastic body 32, the portion between the inner elastic body 31 and the outer elastic body 32, or the inner portion of the inner elastic body 31.

[0163] In the above-described configuration, the hardness of the other elastic body can be set to a different hardness from the inner elastic body 31 and the outer elastic body 32, or to the same hardness as the inner elastic body 31, or to the same hardness as the outer elastic body 32.

[0164] (Tenth alternative embodiment of the invention) The rear right and left portions of the cabin 10 may be supported by right and left vibration-damping rubbers 23 to the rear of the transmission case 6 (aircraft body 3), and the front right and left portions of the cabin 10 may be supported by right and left suspension mechanisms 24 to the clutch housing 5 (aircraft body 3).

[0165] The rear right and left portions of the cabin 10 may be supported by the rear of the transmission case 6 (aircraft body 3) by right and left suspension mechanisms 24, and the front right and left portions of the cabin 10 may be supported by the clutch housing 5 (aircraft body 3) by right and left suspension mechanisms 24.

[0166] (Eleventh alternative embodiment of the invention) The extension and retraction direction of the suspension mechanism 24 may be set not in the vertical direction, but diagonally forward and upward from the aircraft body 3, diagonally backward and upward from the aircraft body 3, diagonally right and upward from the aircraft body 3, or diagonally left and upward from the aircraft body 3.

[0167] According to the above configuration, it is preferable that the stopper member 30 is supported such that the radial direction A2 (see Figure 7) of the stopper member 30 is also diagonally upward and forward from the aircraft body 3, diagonally upward and backward from the aircraft body 3, diagonally upward and to the right from the aircraft body 3, and diagonally upward and to the left from the aircraft body 3.

[0168] (Twelfth alternative form of the invention) The first elastic portion 32a of the outer elastic body 32 of the stopper member 30 and the top plate portion 26c (lower limit receiving portion) of the support member 26 may be retained, while the second elastic portion 32b of the outer elastic body 32 of the stopper member 30 and the upper limit receiving portion 29b of the receiving member 29 may be eliminated.

[0169] The second elastic portion 32b of the outer elastic body 32 of the stopper member 30 and the upper receiving portion 29b of the receiving member 29 may be retained, while the first elastic portion 32a of the outer elastic body 32 of the stopper member 30 and the top plate portion 26c (lower receiving portion) of the support member 26 may be eliminated. In this case, the second elastic portion 32b of the outer elastic body 32 of the stopper member 30 becomes the first elastic portion 32a.

[0170] (13th alternative embodiment of the invention) The stopper member 30 may be configured as a hemisphere obtained by cutting a sphere in half. In this case, when viewing the cross-section 30A of the hemisphere, the inner elastic body 31 of the stopper member 30 will be annular, and the outer elastic body 32 will be circular.

[0171] According to the above configuration, the receiving portion only needs to be provided at a position opposite to the portion of the stopper member 30 (hemispherical) other than the cross-section 30A, and the receiving portion does not need to be provided at a position opposite to the cross-section 30A of the stopper member 30 (hemispherical).

[0172] In the above configuration, if the stopper member 30 (hemispherical) is installed on the cabin 10 such that its cross-section faces the rear of the aircraft body 3, the stopper member 30 can be made to function with respect to the vertical, horizontal, and forward movement of the cabin 10.

[0173] In the above configuration, if the stopper member 30 (hemispherical) is installed on the cabin 10 such that its cross-section 30A faces forward of the aircraft body 3, the stopper member 30 can be made to function against vertical, horizontal, and rearward movement of the cabin 10.

[0174] (14th alternative embodiment of the invention) In the stopper member 30, a spherical inner elastic body 31 may be provided, and an outer elastic body 32 may be provided over the entire outer surface of the inner elastic body 31, so that the entire stopper member 30 is spherical in shape. With this configuration, by providing numerous receiving parts on the outside of the stopper member 30 so as to surround the stopper member 30, the stopper member 30 can function in all directions. With the above configuration, in the stopper member 30, the outer elastic body 32 is provided so as to enclose the outer periphery of the inner elastic body 31.

[0175] (15th alternative embodiment of the invention) Instead of the front wheel 1, a crawler-type running gear (not shown) may be provided as the front running gear. Instead of the rear wheel 2, a crawler-type running gear (not shown) may be provided as the rear running gear. The front wheel 1 and rear wheel 2 may be composed of a single crawler-type running gear (not shown). [Industrial applicability]

[0176] This invention can be applied not only to tractors, but also to agricultural work vehicles such as combine harvesters equipped with cabins, and construction work vehicles such as backhoes and wheel loaders equipped with cabins. [Explanation of Symbols]

[0177] 1. Front wheels (running gear) 2. Rear wheels (running gear) 3 aircraft 9. Driver's Unit 10 cabins 24 Suspension mechanism 26c Top plate section (lower limit support section) (support section) 29b Upper receiving part (receiving part) 29c Intermediate support section (upper support section) (horizontal support section) 29d Horizontal support section 29e Intermediate support section (upper support section) (horizontal support section) 29f Horizontal support section 30 Stopper member 30A cross section 31. Inner elastic body 32 Outer elastic body 32a First elastic section 32b Second elastic section 32c Second elastic section (third elastic section) 32d Third elastic section 32e Second elastic section (third elastic section) 32f Third Elastic Section A1 direction A2 Radial W11 width W21 width W12 width W13 width W22 width

Claims

1. The aircraft body is supported by a traction device, The driver's compartment where the worker sits, A cabin housing the aforementioned driver's unit, A suspension mechanism that supports the cabin on the aircraft body, A stopper member provided on one of the aircraft body and the cabin, The aircraft body and the other of the cabin are provided with a receiving portion, As the suspension mechanism expands and contracts, the stopper member and the receiving portion come into contact, and the stopper member is compressed, thereby stopping the cabin at at least one of the lower limit position of the cabin relative to the aircraft body and the upper limit position of the cabin relative to the aircraft body. The stopper member comprises an inner elastic body and an outer elastic body positioned on the outer part of the inner elastic body and connected to the inner elastic body, having a hardness lower than that of the inner elastic body and contacting the receiving portion. The outer elastic body is a work vehicle in which the cross-sectional shape of the machine body along the vertical direction is formed in an annular shape that surrounds the outer part of the inner elastic body.

2. The work vehicle according to claim 1, wherein the stopper member has a cross-section along the vertical direction of the machine body, and the cross-section is provided so as to be along the left-right direction of the machine body.

3. The work vehicle according to claim 1, wherein the stopper member has a cross-section along the vertical direction of the machine body, and the cross-section is provided so as to be along the front-rear direction of the machine body.

4. The work vehicle according to claim 1, wherein the outer elastic body is provided so as to enclose the outer periphery of the inner elastic body.

5. A machine body supported by a traveling device, The driver's compartment where the worker sits, A cabin housing the aforementioned driver's unit, A suspension mechanism that supports the cabin on the aircraft body, A stopper member provided on one of the aircraft body and the cabin, A receiving portion having an upper limit receiving portion and a lower limit receiving portion is provided on the other of the aircraft body and the cabin, As the suspension mechanism expands and contracts, the stopper member and the receiving portion come into contact, and the stopper member is compressed, causing the cabin to stop at the lower limit position relative to the aircraft body and the upper limit position relative to the aircraft body. The stopper member comprises an inner elastic body formed in the shape of a disc, and an outer elastic body positioned on the outer part of the inner elastic body and connected to the inner elastic body, having a hardness lower than that of the inner elastic body, and in contact with the receiving portion. The stopper member has a first elastic portion which is the portion of the outer elastic body facing the lower limit receiving portion and is connected to one of the upper and lower parts of the inner elastic body, and a second elastic portion which is the portion of the outer elastic body facing the upper limit receiving portion and is connected to the other of the upper and lower parts of the inner elastic body. As the suspension mechanism contracts, the first elastic portion and the lower limit receiving portion come into contact, compressing the first elastic portion and the inner elastic body, thereby stopping the cabin at the lower limit position. A work vehicle in which, due to the extension of the suspension mechanism, the second elastic part and the upper limit receiving part come into contact, the second elastic part is compressed, and the inner elastic body is compressed, thereby stopping the cabin at the upper limit position.

6. The outer elastic body is connected to the entire circumference of the outer periphery of the inner elastic body. The portion of the outer elastic body facing the lower limit receiving portion is the first elastic portion, The portion of the outer elastic body facing the upper limit receiving portion is the second elastic portion, The work vehicle according to claim 5, wherein the outer elastic body is compressed along the radial direction of the inner elastic body, and the inner elastic body is compressed.

7. A horizontal support portion is provided on the other of the aircraft body and the cabin. The stopper member is a portion of the outer elastic body facing the horizontal receiving portion and has a third elastic portion connected to the inner elastic body. The work vehicle according to claim 5, wherein when the cabin moves horizontally relative to the machine body, the third elastic part and the horizontal receiving part come into contact, the third elastic part is compressed, and the inner elastic body is compressed, thereby stopping the cabin at the horizontal limit position relative to the machine body.

8. The outer elastic body is connected to the entire circumference of the outer periphery of the inner elastic body. The portion of the outer elastic body facing the lower limit receiving portion is the first elastic portion, The portion of the outer elastic body facing the upper limit receiving portion is the second elastic portion, The portion of the outer elastic body facing the horizontal receiving portion is the third elastic portion. The work vehicle according to claim 7, wherein the outer elastic body is compressed along the radial direction of the inner elastic body, and the inner elastic body is compressed.

9. An intermediate support portion is provided between the upper limit support portion and the horizontal support portion. The intermediate support portion is a part of the upper support portion and a part of the horizontal support portion. The work vehicle according to claim 8, wherein the portion of the outer elastic body facing the intermediate receiving portion is a part of the portion of the outer elastic body facing the upper receiving portion, and is also a part of the portion of the outer elastic body facing the horizontal receiving portion.

10. The lower limit receiving portion, the upper limit receiving portion, the horizontal receiving portion, and the intermediate receiving portion are connected, The work vehicle according to claim 9, wherein the lower limit receiving portion, the upper limit receiving portion, the horizontal receiving portion, and the intermediate receiving portion are provided so as to surround the outer periphery of the outer elastic body.

11. A work vehicle according to any one of claims 1 to 10, wherein the width of the inner elastic body in a direction perpendicular to the radial direction and the width of the outer elastic body in a direction perpendicular to the radial direction are the same.

12. The work vehicle according to any one of claims 1 to 10, wherein the radial width of the inner elastic body is greater than the radial width of the outer elastic body.

13. The work vehicle according to any one of claims 1 to 10, wherein the inner elastic body and the outer elastic body are made of urethane.

14. The work vehicle according to claim 13, wherein the outer elastic body is foamed urethane.

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