JP2001130422A - Steering cylinder mounting structure of working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a front axle case of high strength capable of supporting a steering cylinder for front wheels while reducing a weight of the front axle case and the manufacturing cost. SOLUTION: In this steering cylinder mounting structure of a working vehicle provided with a steering cylinder 20 for front wheel 4, on a front or rear part of a front axle case 14, a long cylinder mounting member 21 comprising a cylinder mounting part 21a for mounting the steering cylinder 20 is bonded along the longitudinal direction of the front axle case 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering cylinder mounting structure for a working vehicle in which a steering cylinder for a front wheel is disposed on one of front and rear sides of a front axle case.

[0002]

2. Description of the Related Art Conventionally, in a steering cylinder mounting structure for a work vehicle as described above, a steering cylinder is bolted to a cast front axle case.

[0003]

According to the above prior art, it is necessary to increase the thickness of the front axle case as a whole in order to provide the front axle case with sufficient strength to support the steering cylinder. Therefore, the weight of the front axle case becomes heavy, and the pedestal for mounting the steering cylinder must be formed integrally with the front axle case, which complicates the shape of the mold. As a result, the manufacturing cost is increased.

[0004] It is an object of the present invention to reduce the weight of the front axle case and to reduce the manufacturing cost, while at the same time,
An object of the present invention is to provide a steering cylinder having a high strength capable of supporting a steering cylinder for a front wheel.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, a steering cylinder for a front wheel is disposed at one of front and rear sides of a front axle case. In the steering cylinder mounting structure for a working vehicle, a long cylinder mounting member having a cylinder mounting portion for mounting the steering cylinder is provided on the front axle case along a longitudinal direction of the front axle case. And joined.

According to the first aspect of the present invention, since the strength of the front axle case can be increased by the cylinder mounting member, the thickness of the front axle case can be reduced as a whole to reduce the weight of the front axle case. In addition, the front axle case can be provided with a high enough strength to support the steering cylinder.

In addition, it is not necessary to integrally form a pedestal for mounting the steering cylinder on the front axle case, thereby simplifying the shape of the mold forming the front axle case. This makes it easier and reduces manufacturing costs.

In addition, since the cylinder mounting member is long and is joined along the longitudinal direction of the front axle case, it is necessary to connect the front axle case to the fuselage frame so as to be able to roll around the longitudinal axis. In this case, the cylinder mounting member can also be used as a restricting member that restricts the rolling of the front axle case beyond a predetermined range by contact with the body frame etc. As a result, the structure can be simplified, and the durability of the front axle case can be improved as compared with the case where the front axle case is also used as the regulating member.

[Effect] Therefore, the weight reduction of the front axle case,
The front axle case can be configured to have a high strength capable of supporting the steering cylinder for the front wheels, while facilitating the manufacture and reducing the manufacturing cost. Rolling control of the front axle case in the case where the front axle case is rotatably connected around the shaft center can be performed while simplifying the configuration and improving the durability of the front axle case.

[Structure] According to a second aspect of the present invention, in the first aspect, a channel member having a U-shaped cross section is employed for the cylinder mounting member.

According to the second aspect of the present invention, since a commercially available channel material is used as the cylinder mounting member, the sheet metal material is bent into a U-shape in cross section and used as the cylinder mounting member. As compared with the above, the structure can be simplified and a high strength can be obtained.

[Effect] Therefore, the front axle case can be effectively reinforced while further simplifying the structure.

[Structure] According to a third aspect of the present invention, in the second aspect, the cylinder mounting member has a web width substantially equal to a diameter of the front axle case. The width of the flange is substantially the same as or longer than the radius of the front axle case.

According to the third aspect of the present invention, since the cylinder mounting member is fitted to the front axle case, it is possible to suppress contact of the front axle case with other objects. become. Also, since both flanges of the cylinder mounting member can be joined to the front axle case while sandwiching the front axle case, the reinforcement of the front axle case is more effective than when only one of the two flanges is joined. Will be able to do it.

[Effects] Accordingly, it is possible to suppress damage caused by contact of the front axle case with another object, and to more effectively reinforce the front axle case.

[Structure] According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the steering cylinder is provided at both left and right ends of the cylinder mounting member. A cover mounting portion for mounting a cover surrounding each of the left and right piston rods was formed.

According to the fourth aspect of the invention, by attaching covers to the left and right ends of the cylinder mounting member, it is possible to suppress contact of other objects with the left and right piston rods of the steering cylinder. ,
The appearance can be improved as compared with the case where the left and right piston rods are exposed.

[Effect] Accordingly, it is possible to suppress the damage of the steering cylinder caused by the contact of the left and right piston rods with other objects and to improve the appearance.

[Structure] According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the front axle case is provided at a left and right intermediate portion of the cylinder mounting member. A support bracket made of sheet metal for supporting the end on the side where the steering cylinder is provided at the side of the vehicle body on the body frame was joined.

According to the fifth aspect of the present invention, there is no need to integrally form a connecting portion for connecting the end on the steering cylinder arrangement side to the body frame to the front axle case. Accordingly, since the shape of the mold forming the front axle case can be simplified, manufacturing can be facilitated and manufacturing cost can be reduced.

[Effects] Therefore, the simplification of the production and the reduction of the production cost can be more effectively achieved.

[Structure] In the invention according to claim 6 of the present invention, in the invention according to any one of claims 1 to 5, the support bracket is overlapped with the cylinder mounting member.

[Operation] According to the sixth aspect of the invention, the front axle case can be reinforced by both the cylinder mounting member and the support bracket.

[Effect] Therefore, the front axle case can be more effectively reinforced.

According to a seventh aspect of the present invention, there is provided a steering cylinder mounting structure for a working vehicle in which a steering cylinder for a front wheel is disposed on one of front and rear sides of a front axle case. A state in which a sheet metal support bracket for supporting one of the front and rear sides of the front axle case on the body frame is joined to the front axle case, and the steering cylinder is positioned between the front axle case and the support bracket. To the support bracket.

According to the seventh aspect of the present invention, it is necessary to integrally form the pedestal for mounting the steering cylinder and the connecting portion for supporting either the front or rear of the pedestal with the body frame in the front axle case. Since there is no such structure, the shape of the mold forming the front axle case can be simplified accordingly, so that manufacturing can be facilitated and manufacturing costs can be reduced.

Moreover, as the length of the support bracket, which is longer in the longitudinal direction of the front axle case, is adopted, the strength of the front axle case can be increased by the support bracket. The front axle case can be made strong enough to support the steering cylinder while reducing the weight of the front axle case. It can be suppressed effectively. In addition, when the front axle case is connected to the body frame so as to be rotatable around the front-rear axis, the support bracket may be in contact with the body frame or the like to restrict the rolling of the front axle case beyond a predetermined range. This makes it possible to simplify the configuration as compared with a case where a regulating member having a different configuration is newly provided, and further, as compared with a case where the front axle case is also used as the regulating member. The durability of the case can be improved.

In particular, if a long bracket that surrounds the left and right piston rods of the steering cylinder is adopted as the support bracket, the appearance can be improved as compared with the case where the left and right piston rods are exposed. become.

[Effect] Therefore, the weight reduction of the front axle case,
The front axle case can be configured to have a high strength capable of supporting the steering cylinder for the front wheels, while facilitating the manufacture and reducing the manufacturing cost. It is possible to control the rolling of the front axle case in a case where it is rotatably connected around the shaft center while simplifying the configuration and improving the durability of the front axle case. Damage of the steering cylinder due to contact can be suppressed, and the appearance can be improved.

[Configuration] According to an eighth aspect of the present invention, in the invention according to any one of the fifth to seventh aspects, a steering angle of the front wheel is detected by the support bracket. The steering angle detection mechanism was supported.

According to the eighth aspect of the present invention, the shape of the mold for forming the front axle case is smaller than when the supporting portion for supporting the steering angle detecting mechanism is formed integrally with the front axle case. Because it can be simplified, it will be possible to make manufacturing easier and reduce manufacturing costs,
Further, compared to a case where a support member having a different configuration for supporting the steering angle detection mechanism is newly provided, the configuration can be simplified and the manufacturing cost can be reduced.

[Effects] Therefore, it is possible to facilitate the manufacture of the apparatus equipped with the steering angle detecting mechanism, simplify the structure, and reduce the manufacturing cost.

[Configuration] According to a ninth aspect of the present invention, in the above-mentioned seventh aspect, the steering angle detecting means is provided in parallel with the steering cylinder. Both ends are configured to detect the steering angle of the front wheel from the amount of movement of the operation angle detection rod connected to the left and right piston rods of the steering cylinder, and the steering angle detection rod is mounted on the front axle case. The support bracket supported the support bracket in a state where the support bracket was positioned between the support bracket and the support bracket.

According to the ninth aspect of the present invention, the contact of the steering angle detection rod with other objects can be suppressed, and the steering angle can be controlled within the length range of the steering angle detection rod. The arrangement position of the detection means can be freely changed.

[Effect] Accordingly, it is possible to suppress breakage due to the contact of the steering angle detection rod with another object, and to increase the degree of freedom of the arrangement position of the steering angle detection means.

[Structure] According to a tenth aspect of the present invention, in the invention according to any one of the first to ninth aspects, the front axle case is constituted by a sheet metal tubular body. .

According to the tenth aspect of the present invention, it is possible to effectively utilize the fact that the front axle case can be sufficiently reinforced by the above-described structure such as joining the cylinder mounting member and the support bracket to the front axle case. Since the front axle case is made of a sheet metal tubular body whose wall thickness can be made thinner than when casting, the weight of the front axle case can be significantly reduced. In addition, since it is not necessary to use a mold in forming the front axle case, it is possible to greatly simplify the production and reduce the production cost.

[Effects] Accordingly, the rational improvement by effectively utilizing the above-described configuration has made it possible to significantly reduce the weight of the front axle case, facilitate the manufacture thereof, and reduce the manufacturing cost.

[0039]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an overall side view of a tractor as an example of a work vehicle, and this tractor is connected to an engine 1 provided at a front portion of an airframe and a rear portion of the engine 1. A transmission case 2 serving also as a frame, an airframe 3 connected to the engine 1 so as to extend forward, a front wheel 4 disposed on the left and right of the airframe 3, and a rear wheel disposed on the rear left and right of the transmission case 2. 5, a steering wheel 6 linked to the front wheels 4, a driver seat 7 disposed behind the steering wheel 6, and the like.

As shown in FIG. 2, in the transmission case 2, the main clutch 8 interrupts the transmission of the power from the engine 1, and the power transmitted from the engine 1 via the main clutch 8 is continuously variable. A hydrostatic continuously variable transmission 9, an auxiliary transmission 10 that shifts the power after shifting from the hydrostatic continuously variable transmission 9 into three stages, and an auxiliary transmission that allows the left and right rear wheels 5 to be differential. The power after shifting from the rear wheels 10
, A DT clutch 12 for intermittently transmitting power from the auxiliary transmission 10 to the left and right front wheels 4, and an auxiliary transmission 10 transmitted via the DT clutch 12. And a hydraulic front wheel speed-up device 13 for shifting the power after the speed change in two stages.

As shown in FIGS. 2 to 5, a front axle case 14 is supported on the body frame 3 so as to be rotatable about the longitudinal axis P1 below the body frame 3. The front wheel 4 is steerably connected around the axis P2 in a state where the front wheel 4 has a predetermined kingpin angle via hub cases 16 rotatably supported around the axis P2 of the king pin 15 at both left and right ends thereof. ing. In addition, the front axle case 14 is provided with a front wheel speed increasing device 13 that is transmitted through a transmission shaft 17 disposed on the front-rear axis P1.
A front wheel differential device 18 for distributing and transmitting the power after shifting from the left and right front wheels 4 to the left and right front wheels 4 in a state in which the left and right front wheels 4 can be differentiated is provided.

As shown in FIGS. 3 to 5, the front axle case 14
Is a sheet metal tubular body 14A formed in a circular cross section,
The hub case 16 includes a connection flange 14B made of sheet metal welded to both ends thereof, and a rear boss 14C welded to a rear portion of the cylindrical body 14A around the longitudinal axis P1. Left and right connecting flanges 14
B is supported via a fixed case 19 which is bolted to B, and the front end side of the transmission shaft 17 is supported by a rear boss 14C. That is, compared with the case where the cast front axle case 14 is employed, the front axle case 14
This makes it possible to reduce the weight, facilitate manufacture, and reduce the manufacturing cost.

A cylinder mounting member 21 for mounting a hydraulic steering cylinder 20 for steering the left and right front wheels 4 is provided on the cylindrical body 14A of the front axle case 14 along the longitudinal direction of the front axle case 14. Are joined. The cylinder mounting member 21 has a long overall length substantially equal to the entire length of the front axle case 14, and the width of the web 21 </ b> A is
A is approximately the same length as the diameter of A, and both flanges 21B
A channel material having a U-shaped cross section whose width is substantially the same as the radius of the cylindrical body 14A is adopted, and a web 21A having screw holes serving as cylinder mounting portions 21a at both left and right end portions is provided forward. In the facing state, each end of both flanges 21B sandwiches the cylindrical body 14A so as to sandwich the cylindrical body 14A.
Is to be welded. That is, the steering cylinder 20 can be disposed in front of the front axle case 14 in parallel with the front axle case 14 while reinforcing the front axle case 14 with the cylinder mounting member 21.

The steering cylinder 20 is of a double-acting, double-rod type. The supply / discharge ports 20 a formed at both ends of the cylinder tube 20 A are steered according to the operation of the steering wheel 6. A control valve 22 for controlling the flow state of hydraulic fluid to the directional cylinder 20 is connected via a hydraulic hose 23 to the left and right piston rods 20B.
Is a knuckle arm 1 integrally formed with the hub case 16.
6A is connected via a universal joint 24 and a ball joint 26. In other words, the left and right front wheels 4 can be steered to a steering angle corresponding to the operation amount of the steering wheel 6 by the operation of the control valve 22 in conjunction with the operation of the steering wheel 6, and the left and right front wheels 4 can be steered during the steering operation. Between the piston rod 20B and the knuckle arm 16A due to the kingpin angle can be avoided. The left and right piston rods 20B,
The universal joint 24 and the ball joint 26 are threadedly connected.

At the left and right intermediate portions of the cylinder mounting member 21,
A support bracket 27 made of a sheet metal for supporting the front end portion of the front axle case 14 on the side where the steering cylinder 20 is provided on the body frame 3 is joined. The support bracket 27 is formed so as to be bent in a substantially U-shape when viewed from the side, and has a lateral width of the steering cylinder 20.
The length of the cylinder tube 2 of the steering cylinder 20 is set to be substantially the same as the length between the left and right supply / discharge ports 20a.
0A is surrounded from the front, and both upper and lower edges thereof are welded to both flanges 21B of the cylinder mounting member 21 in a state where both upper and lower ends thereof are overlapped with both flanges 21B of the cylinder mounting member 21. Has become. In other words, the support bracket 27 can suppress the contact of the steering cylinder 20 with other objects to the cylinder tube 20A without causing the inconvenience that the attachment and detachment of the hydraulic hose 23 to each of the supply / discharge ports 20a of the steering cylinder 20 becomes difficult. ,
The reinforcement of the front axle case 14 can be performed more effectively.

At the front end of the support bracket 27, a front boss 27A centering on the front-rear axis P1 is welded. The front boss 27A and the rear boss 14C of the front axle case 14 are welded.
Are rotatably supported by the body frame 3 so that the front axle case 14 is attached to the body frame 3 by the front-rear axis P1.
It is designed to be freely rolled around.
The long cylinder mounting member 21 joined to the front axle case 14 is a regulating member that regulates the rolling of the front axle case 14 beyond a predetermined range by contact with the left and right front-rear frames 3A of the body frame 3. As a result, the structure can be simplified as compared with the case where a separate regulating member is newly provided, and the front axle case 1 can be used.
Front axle case 1 generated when 4 is used also as a regulating member
4 can be prevented from being deformed or damaged.

A guide member 28 having a U-shaped cross section is fixed on the upper surface of the support bracket 27 in a parallel posture with respect to the steering cylinder 20. A rod 29 disposed parallel to the steering cylinder 20 is engaged with the guide member 28. Both ends of the rod 29 are connected to the outer ends of the left and right piston rods 20B so that the rods 29 move integrally with the left and right piston rods 20B of the steering cylinder 20.
0. That is, the guide member 28,
The rod 29 and the left and right connecting plates 30 constitute a detent mechanism A for preventing the left and right piston rods 20B from rotating around the axis P3 within the allowable range of the universal joint 24 and the ball joint 26. This causes the left and right piston rods 20B to rotate around their axis P3, thereby causing the left and right piston rods 20B to rotate.
B, the universal joint 24 and the threaded portion 31 of the ball joint 26 can be prevented from becoming loose.

At the left and right ends of the cylinder mounting member 21,
Left and right piston rods 20B of the steering cylinder 20,
A plurality of screw holes 21b for connecting bolts to a sheet-metal cover 32 bent so as to surround both ends of the rod 29 exposed on both the left and right sides of the body frame 3 are formed as cover attaching portions. By attaching the cover 32 to these cover attachment portions 21b, it is possible to suppress the contact of the left and right piston rods 20B and the rods 29 with other objects at both ends of the left and right piston rods 20B and 29. The outer appearance can be improved as compared with the case where both end sides are exposed.

On the upper part of the support bracket 27, the rod 2
A steering angle detection mechanism B for detecting the steering angle of the front wheel 4 from the amount of movement of the steering wheel 9 is provided. More specifically, the steering angle detection mechanism B
Is a rod 29 functioning as a steering angle detection rod by integrally moving with the left and right piston rods 20B of the steering cylinder 20 that steers the front wheel 4; A support member 33 having a substantially U-shaped cross-section and connected to be positioned between the frames 3A. The support member 33 is supported by the lower portion of the support member 33 so as to be swingable about the longitudinal axis P4 and forward from the support member 33. A swing arm 34 extending toward the front end, a pin 35 erected on the rod 29 so as to pass through a long hole 34A facing the front end formed on the free end side of the swing arm 34, and a front and rear middle of the swing arm 34 The U-shaped operating tool 36 erected on the section and the rotation as an example of a detecting means fixed to the upper part of the support 33 so that the neutral return type detection arm 37A is engaged with the operating tool 36. Expression Potential The rod 29 is moved by the operation of the steering cylinder 20 in conjunction with the operation of the steering wheel 6, and the operating tool 36 on the swing arm 34 is detected by the movement of the rod 29 by a predetermined amount or more. The potentiometer 37 detects that the arm 37A has been pressed, thereby detecting that the front wheel 4 has been steered beyond a predetermined angle in order to perform a so-called ridge turn in which the airframe makes a small turn at the ridge of the field. It has become. That is, since the rod 29 of the rotation preventing mechanism A is also used as the steering angle detection rod of the steering angle detection mechanism B, the configuration is simplified and the manufacturing is simplified as compared with the case where a dedicated steering angle detection rod is provided. The cost can be reduced. The swing arm 3
4 and the potentiometer 37 can be disposed above the front axle case 14 and the support bracket 27 and between the left and right front-rear frames 3A of the body frame 3, so that the front wheels 4 bounce against them. Adhesion of the raised soil and the contact with other objects can be effectively suppressed.

As shown in FIG. 4, the potentiometer 37 of the steering angle detecting mechanism B inputs its detection to a control device 38 mounted on the body of the vehicle.
Is based on the detection from the potentiometer 37.
When it is detected that the steering operation has been performed at a predetermined angle or more, the operation of the electromagnetic switching valve 39 that switches the flow state of the hydraulic oil to the front wheel speed increasing device 13 is controlled to cause the front wheels 4 to move to the rear wheels 5. The speed-up drive state that drives at twice the speed of
Further, based on the detection from the potentiometer 37, the front wheels 4
When it is detected that the steering operation has not been performed to the predetermined angle, the operation of the electromagnetic switching valve 39 is controlled to display the constant speed drive state in which the front wheels 4 are driven at substantially the same speed as the rear wheels 5. The vehicle is configured to perform front wheel speed-up control, such as to make the vehicle go out, so that turning on a ridge in a field can be smoothly performed without damaging the field.

[Other Embodiments] Other embodiments of the present invention will be listed below. The work vehicle may be a rice transplanter, a direct sowing machine, or the like as long as the steering cylinder 20 is disposed on one of the front and rear sides of the front axle case 14. The front axle case 14 may be formed by using a sheet metal tubular body 14A having a polygonal cross section such as a quadrangle or a hexagon, or may be formed by casting. You may make it. The steering cylinder 20 may be disposed behind the front axle case 14 by joining the cylinder mounting member 21 to the front axle case 14 in a state of being externally fitted to the rear axle case 14. Cylinder mounting member 2 provided with screw holes 21a at both left and right ends of flange 21B
The steering cylinder 20 may be disposed on the front axle case 14 so as to be fitted to the front axle case 14 from the up-down direction. The cylinder mounting member 21 may include a stud bolt as the cylinder mounting portion 21a. As the cylinder mounting member 21, a channel material formed so that the width of the flange 21B is equal to or longer than the radius of the front axle case 14 may be adopted.
An angle member having an L-shaped cross section may be employed. The steering cylinder 20 may be mounted on the support bracket 27 so that the cylinder mounting member 21 functions only as a reinforcing member for the front axle case 14. As shown in FIG. 6, a state in which the support bracket 27 is joined to the front axle case 14 without providing the cylinder mounting member 21 and the steering cylinder 20 is positioned between the front axle case 14 and the support bracket 27. By attaching to the support bracket 27, the structure may be simplified and the manufacturing cost may be reduced more effectively. Further, in this configuration, as shown in the figure, a guide member 28 and a rod 29 are disposed between the front axle case 14 and the support bracket 27 which are positions where the cylinder mounting member 21 is disposed in the above embodiment. Then, the guide member 28
In addition, it may be possible to more effectively suppress the adhesion of the soil and the like jumped up by the front wheel 4 to the rod 29 and the contact of other objects. Further, in this configuration, as shown in the figure, the guide member 28 is joined to the front axle case 14 along the longitudinal direction thereof, so that the front axle case 14 is further reinforced by the guide member 28. Is also good. As the support bracket 27, one having a lateral width set to be substantially the same as the entire length of the front axle case 14 is adopted, and the support bracket 27 is provided with the function of the cover 32, thereby simplifying the configuration and manufacturing cost. May be further reduced. The front axle case 14 may be fixedly supported by the body frame 3 so that it cannot be rolled.

[Brief description of the drawings]

FIG. 1 is an overall side view of a tractor.

FIG. 2 is a schematic side view showing a transmission configuration in a transmission case.

FIG. 3 is a cross-sectional plan view of a main part showing a configuration around a front axle case.

FIG. 4 is a longitudinal sectional side view of a main part showing a configuration around a front axle case.

FIG. 5 is a front view of a main part showing a configuration around a front axle case;

FIG. 6 is a longitudinal sectional side view of a main part showing a configuration around a front axle case in another embodiment.

[Explanation of symbols]

 3 Body Frame 4 Front Wheel 14 Front Axle Case 14A Cylindrical Body 20 Steering Cylinder 20B Piston Rod 21 Cylinder Attachment Member 21A Web 21B Flange 21a Cylinder Attachment 21b Cover Attachment 27 Support Bracket 29 Operating Angle Detecting Rod 32 Cover B Steering Angle Detection mechanism

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Satoshi Oizumi 64 Ishizukitamachi, Sakai City, Osaka Prefecture Inside Kubota Sakai Works (72) Inventor Seiji Nishimura 64 Ishizukitamachi, Sakai City, Osaka Prefecture Kubota Sakai Co., Ltd. F term in the factory (reference) 3D033 AA01 HA05

Claims (10)

[Claims] 1. A steering cylinder mounting structure for a working vehicle, wherein a steering cylinder for a front wheel is disposed on one of front and rear sides of a front axle case, wherein the steering cylinder is mounted on the front axle case. A steering cylinder mounting structure for a working vehicle, wherein a long cylinder mounting member provided with a cylinder mounting portion for connecting the same along the longitudinal direction of the front axle case. 2. A steering cylinder mounting structure for a working vehicle according to claim 1, wherein a channel member having a U-shaped cross section is adopted as said cylinder mounting member. 3. The cylinder mounting member according to claim 1, wherein the width of the web is substantially equal to the diameter of the front axle case, and the width of the flange is substantially equal to or greater than the radius of the front axle case. Item 3. A steering cylinder mounting structure for a work vehicle according to Item 2. 4. At both left and right ends of the cylinder mounting member,
The steering cylinder mounting structure for a working vehicle according to any one of claims 1 to 3, wherein a cover mounting portion for mounting a cover surrounding each of the left and right piston rods of the steering cylinder is formed. 5. In the left and right intermediate portions of the cylinder mounting member,
The steering cylinder mounting structure for a working vehicle according to any one of claims 1 to 4, wherein a support bracket made of a sheet metal for supporting an end of the front axle case on the steering cylinder disposition side to an airframe is joined. 6. The steering cylinder mounting structure for a working vehicle according to claim 1, wherein the support bracket is overlapped with the cylinder mounting member. 7. A steering cylinder mounting structure for a working vehicle, wherein a steering cylinder for a front wheel is disposed on one of front and rear sides of a front axle case, wherein one of the front and rear sides is attached to the front axle case. A work bracket attached to the support bracket with the steering cylinder positioned between the front axle case and the support bracket is joined together with a sheet metal support bracket for supporting the body frame. Oriented cylinder mounting structure. 8. A steering angle detecting mechanism for detecting a steering angle of the front wheel is supported by the support bracket.
The steering cylinder mounting structure for a working vehicle according to any one of claims 1 to 7. 9. A moving amount of an operating angle detecting rod, wherein the steering angle detecting means is disposed in parallel with the steering cylinder and both ends are connected to left and right piston rods of the steering cylinder. The steering angle detection rod is configured to detect the steering angle of the front wheel from the front, and the steering angle detection rod is supported by the support bracket while being positioned between the front axle case and the support bracket. The steering cylinder mounting structure for the working vehicle described in the above. 10. The steering cylinder mounting structure for a working vehicle according to claim 1, wherein the front axle case is formed of a sheet metal tubular body.