JP2003341526A - Steering wheel attaching structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering wheel attaching structure not causing slack at a connecting portion between a steering post and a power steering unit. <P>SOLUTION: A power steering unit 41 having a flange 41 at a bottom end accommodating a member for a power steering is attached to a base of a wheel shaft 56 equipped with the steering wheels 38. The power steering unit 41 is attached to an opening 49a for inserting the steering unit 41 installed to a bracket 49 of a steering post 39 as a support member of the power steering unit 41. The flange 41a of the power steering unit 41 is fixated with the bracket 49 of the steering post 39 by elastic members 59, 60 arranged above and below the bracket 49 of the steering post 39. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering handle mounting structure including a power steering unit for a work vehicle for agriculture, construction, transportation and the like.

[0002]

2. Description of the Related Art A tractor will be described below as an example of a work vehicle. The front and rear wheels of the tractor are supported by a vehicle body that is a main frame, and an engine, a mission case, etc. are mounted on the vehicle body. Rotational power of the engine is transmitted to a transmission, a front / rear switching device, and the like in the transmission case to drive the front wheels and the rear wheels. In some cases, the tractor has a mid-mower for lawn mowing at the bottom of the vehicle body.

The steering handle of the tractor is attached to a handle attachment support frame (steering post), and a power steering unit is attached via a bracket provided on the steering post.

[0004]

However, when the power steering handle is used to steer the tractor, a large load is applied to the steering post and the power steering unit. Therefore, the steering post and the power steering unit are connected to each other. Loosening is likely to occur in the part. An object of the present invention is to provide a steering handle mounting structure in which a connection portion between the steering post and the power steering unit is not loosened.

[0005]

The present invention has taken the following technical means in order to solve the above-mentioned problems.
That is, according to the first aspect of the invention, the power steering unit 41 having the flange 41a at the lower end for accommodating the power steering member is attached to the base of the handle shaft 56 having the steering handle 38, and the power steering unit 41 is supported. The power steering unit 41 is attached to the steering unit 41 insertion opening 49a provided in the bracket 49 of the steering post 39, which is a member, and the power steering unit is provided by elastic members 59 and 60 arranged above and below the bracket 49 of the steering post 39. This is a steering handle mounting structure in which a flange 41a of 41 and a bracket 49 of the steering post 39 are fixed.

According to the second aspect of the present invention, the flange 41a of the power steering unit 41 and the bracket 49 of the steering post 39 are attached to the elastic member 5 by the bolt 58.
The steering handle mounting structure according to claim 1, wherein the steering handle mounting structure is fixed via 9, 60.

The invention according to claim 3 is the steering handle mounting structure according to claim 2, wherein the bolt is a stud bolt 66 fixed to the flange 41a of the power steering unit 41.

According to the fourth aspect of the present invention, the fuel filter 43 is arranged on the outer surface of the lower end portion of the steering post 39 below the floor surface 42 provided at the lower end portion of the steering post 39. It is a steering handle mounting structure.

According to the first aspect of the invention, the power steering unit 41 is supported and fixed to the steering post 39 via the elastic members (rubber washers or the like) 59 and 60 which are elastic bodies, so that the vibration of the handle 38 is reduced. . While the elastic members (rubber washers, etc.) 59, 60 are deformed, the steering post 39 and the power steering unit 41 are firmly supported and fixed.

According to the invention of claim 2, as an example of the invention of claim 1, the power steering unit 41 and the steering post 39 can be easily and firmly assembled by using the bolt 58.

According to the invention of claim 3, in addition to the invention of claim 1, the lower elastic member (rubber washer etc.) 59 of the elastic members (rubber washer etc.) 59, 60 is of the steering unit 41. When the power steering unit 41 is inserted into the central opening 49a of the bracket 49 of the steering post 39 from below while passing through the stud bolt 66 supported by the flange 41a, a lower elastic member (such as a rubber washer) 59 is inserted. There is no risk of slipping.

According to the invention of claim 4, the fuel filter 4 is located outside the engine room at a position surrounded by other parts.
3 can be installed.

[0013]

According to the invention of claim 1, since the power steering unit 41 is supported and fixed to the steering post 39 via the elastic members (rubber washers or the like) 59 and 60, the vibration of the handle 38 is reduced. .

According to the invention of claim 2, as an example of the invention of claim 1, by using the bolt 58, the power steering unit 41 and the steering post 39 can be easily and firmly assembled.

According to the invention of claim 3, in addition to the invention of claim 1, when the power steering unit 41 is inserted into the central opening 49a of the bracket 49 of the steering post 39 from below, the rubber washer 59 slides down. You can easily assemble without fear.

According to the fourth aspect of the invention, the fuel filter 4 is located outside the engine room at a position surrounded by other parts.
By installing 3, there are the following effects. The fuel temperature is lowered and the engine performance is improved. Maintenance of the fuel filter 43 is simple. While having the above effect, it is possible to prevent damage to the fuel filter 43 due to an external force.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. First, the structure of a tractor will be described as an example of a work vehicle. As shown in the side view of FIG. 1 and the plan view of FIG. 2, a main frame 1 of a body of a small agricultural tractor is shown.
The engine 2 is mounted in the hood 6 in the upper front, and the rotational power of the engine 2 is transmitted to the hydrostatic continuously variable transmission (HST) 4 attached to the front part of the mission case 3 via the universal joint 5. .

A transmission is provided in the transmission case 3, and the rotational power finally reduced by the transmission is transmitted to the left and right rear wheels 10, 10. Mission case 3
A front wheel drive shaft 12 for driving the front wheels 11, 11 and a mid PTO shaft 14 for driving a working machine attached to the lower part of the body of the machine are pivotally supported at the front part of the. In this embodiment, a mid-mower 1 for cutting grass and lawn is used as a working machine.
5 is supported by the parallel link mechanism 16. The upper end of the parallel link mechanism 16 is pivotally supported on the main frame 1, and the lower end is pivotally attached to the mid mower 15.

Then, the front wheel drive shaft 12 and the input shaft 19 projecting rearward from the rear portion of the front axle (housing) 18 are connected by a universal joint 20 to drive the front wheels 11 and 11, and at the same time the mid mower is driven. The input shaft 22 on the 15 side and the mid PTO shaft 14 are connected by a universal joint 24 to drive the mid mower 15.

More specifically, a cutting blade drive shaft (not shown) is vertically mounted on the gear case 25 of the mid mower 15, and a cutting blade (not shown) is attached to the lower portion thereof. When the hydraulic PTO clutch 32 in the mission case 3 is connected after the engine 2 is started, the mid PTO shaft 14
Is driven, and the rotation thereof is transmitted to the gear case 25 on the side of the mid mower 15 through the universal joint 24, the cutting blade drive shaft is driven to rotate, and the rotating cutting blade cuts grass and lawn.

The steering direction of the left and right front wheels 11, 11 is controlled by a steering cylinder 23 supported via a steering cylinder mounting seat 21 of the front axle 18. A piston is arranged in a cylinder chamber (not shown) in the steering cylinder 23, and a piston rod 26 that expands and contracts is provided on both sides of the piston. One piston rod 26 is connected to an end portion of a hub case 27 of the front wheel. ing.

A hydraulic cylinder case 34 is mounted on the upper portion of the transmission case 3, and lift arms 35, 35 are rotatably supported on both left and right sides of the hydraulic cylinder case 34. The lift arms 35, 35 are provided for raising and lowering a rotary working machine connected to the rear part of the machine body or a working machine mounted on the lower part of the machine body, and rotate a hydraulic operating lever (not shown) in the front-back direction. By the lift arm 3
5, 35 rotate in the vertical direction.

A steering handle 38 is attached to a steering post 39 via a power steering unit 41 inside the dash cover 36 in the front portion of the driver's seat 37. Below the steering post 39, a floor 42 for getting on and off the driver's seat 37 is provided in a front rising shape, and a fuel filter 43 is arranged outside the lower end portion of the steering post 39 below the front rising portion of the floor 42. Has been done.

FIG. 3 shows a casing 45 of the steering post 39 from which the radiator, the battery and the handle 38 are removed.
A perspective view of the power steering unit 41 attached to the housing 45 is shown. A pair of left and right bent handle attaching frames 46 of the steering post 39 are provided, and the bottom of the frame 46 is attached to the main frame 1 on the vehicle body. The plate 47 is connected by welding, and a bracket 49 for mounting an all-hydraulic power steering case is provided near the top of the frame 47.
Cross over. Further, a pair of bent radiator mounting plates 50 are welded to both side surfaces of the frame 46 below the central portion. A battery mount 52 is welded between the side plates 50a of the radiator mounting plate 50. A reservoir tank mounting plate 53 is provided on the handle mounting frame 46.

In this way, the mounting plates 46, 47, 49,
A radiator, a battery, a steering handle 38, and an all-hydraulic power steering unit 41 are attached to 50, 53, a mounting table 52, and the like.

An all-hydraulic power steering unit 41 is provided at the base of the handle shaft 56 to which the steering handle 38 is attached at the tip.
1. A flange 41a is provided at the lower end of 1, and the flange 41a
A hose 57 for an oil passage is connected to the lower side. Further, the power steering unit 41 is inserted from below into the steering unit insertion opening 49a provided in the bracket 49 of the steering post 39, the flange 41a and the bracket 49 are overlapped, and the four corners of the bracket 49 are bolted by the bolts 58. Fix with.

The driver holds the steering wheel 38 while the tractor is traveling, and the vibration of the engine 2 is transmitted to the steering post 39 through the main frame 1 while the tractor is operating. When the steering wheel 38 is held for a long time, the vibration is transmitted, and the hand becomes tired. Further, when steering the tractor, the steering post 39 and the power steering unit 41 are used.
Since a large load is applied to the steering post 39, the connecting portion between the steering post 39 and the power steering unit 41 is likely to be loosened.

In the present embodiment, the steering post 39
The above problem is solved by adopting a vibration-proof mounting structure in which vibration is less likely to be transmitted to the steering handle 38 side from the connecting portion between the power steering unit 41 and the power steering unit 41 and is not loosened.

FIG. 4 is a side sectional view of a connecting portion between the steering post 39 and the power steering unit 41, and FIG. 5 is a view taken along the line AA of FIG. When the power steering unit 41 is inserted from the lower side of the steering unit insertion opening 49a provided in the center of the bracket 49, the rubber washer 59 is provided on the bolt holes 41b at the four corners of the flange 41a of the power steering unit 41.
The collar 61 is placed, and the power steering unit 41 is inserted into the opening 49a at the center of the bracket 49 from below while applying the bolt steering hole 49b of the bracket 49 from below. In that state, while holding the power steering unit 41 by hand, another rubber washer 60 and metal washers 62, 63 are sequentially stacked from the upper side of the bolt insertion small hole 49b of the bracket 49, and the bolt 58 is inserted from above. The upper and lower rubber washers 59,
Tighten 60 and collar 61 tightly. The width of the collar 61 can adjust the distance between the upper and lower rubber washers 59 and 60, and the tightening force of the rubber washers 59 and 60 by the bolts 58 can be regulated.

In this way, the power steering unit 4
Since 1 is supported and fixed to the steering post 39 via the rubber washers 59 and 60 which are elastic bodies, the vibration of the steering wheel 38 is reduced.

At this time, the rubber washer 5 which is an elastic body
While the 9 and 60 are deformed, the steering post 39 and the power steering unit 41 are firmly supported and fixed.

An example in which a slight modification is applied to the configuration described in FIGS. 4 and 5 is a side sectional view of FIG. 6 and AA of FIG. 6 of FIG.
It is shown in the arrow view. The feature of the configuration shown in FIGS. 6 and 7 is that the stud bolt 66 is used as the bolt and the bolt is inserted into the bolt holes 41b at the four corners of the flange 41a of the power steering unit 41 from the beginning.

Therefore, the pair of rubber washers 59, 60
The rubber washer 59 on the lower side of the bottom of the power steering unit 41 is inserted into the central opening 49a of the bracket 49 of the steering post 39 from below with the stud bolt 66 attached to the flange 41a of the steering unit 41 being passed through from the beginning. Rubber washer 5 when inserting
9 can be easily assembled without the risk of slipping.

After the power steering unit 41 is attached to the bracket 49 of the steering post 39, the other rubber washer 60 is passed through the stud bolt 66 protruding above the small hole 49b of the bracket 49, and finally the two mounting nuts 67 are used to attach the two rubber washers. Tighten 59 and 60. Further, at this time, as shown in FIG. 7, when the four sets of rubber washers 59 and 60 are assembled with the inner edges thereof abutting the power steering unit, the power steering unit 4
1. No rattling in the lateral direction.

As described above, since the rubber washer 60 can be easily assembled from the top of the bracket 49 without the risk of dropping the rubber washer 59, as shown in FIGS. Also in the configuration shown in FIG. 7, the power steering unit 41 is firmly supported and fixed to the steering post 39, and the anti-vibration effect of the handle 38 is exerted. The same can be said for the rubber washers 59 and 60 shown in FIGS. 4 and 5.

A steering handle 38 is attached to a front portion of the driver's seat 37 on a steering post 39 via a power steering unit 41. Below the steering post 39, a boarding / alighting floor 42 of the driver's seat 37 is provided. The fuel filter 43 is provided in a front rising shape, and is below the front rising portion of the floor 42 and outside the lower end portion of the handle mounting frame 46 of the steering post 39.

FIG. 8 shows a plan view of the arrangement portion of the fuel filter 43, FIG. 9 shows a side view thereof, and FIG.
A view of the AA line is shown, but inside the link 16 on the left side of the mid mower 15 on the left side of the main frame 1 of the airframe (hereinafter, left side and right side are the left and right positions when facing the tractor advancing direction). The fuel filter 43 is disposed above (on the right side) and at a position surrounded by the outside of the wall surface of the floor panel 42 and the lower end of the handle mounting frame 46 of the steering post 39. A front panel front end attaching / detaching portion 70 is provided in front of the floor panel 42. Also, FIG.
As shown in the plan view of FIG. 1, the pair of main frames 1 and 1 are connected by the left and right connecting plates 72.

As described above, by installing the fuel filter 43 outside the engine room at a position surrounded by other parts, the following effects can be obtained. The fuel temperature is lowered and the engine performance is improved. Maintenance of the fuel filter 43 is simple. While having the above effect, it is possible to prevent damage to the fuel filter 43 due to an external force.

Further, the steering cylinder 23 of the present embodiment is
Since the ends of the cylindrical case are only held by the plate 76 having the receiving portion of the round hole in a state where the piston rods 26 are extendably attached to both ends of the cylindrical case, the steering cylinder 23 itself does not move within the round hole of the plate. Easy to rotate. When the steering cylinder case rotates, other members such as hydraulic hoses and hose fixtures that are engaged with the steering cylinder 23 may move, interfere with the axle brackets, and may be displaced from their original installation positions. is there.

Therefore, a plan view of the steering cylinder installation portion of FIG. 11 and a side view of the steering cylinder portion of FIG. 12 (A in FIG. 11)
As shown in the arrow A line view), an attachment structure (stopper structure) for the rotation preventing member of the steering cylinder 23 was manufactured.

The anti-rotation device has a steering cylinder 23 mounted on a boss 18a provided near the end of the axle case 18.
A projection portion 23a having an opening for inserting a bolt to be described later is provided in the vicinity of the end portion of the steering wheel 23 and the plate 76 is attached to the end portion of the steering cylinder 23.

Then, the bolt 77 for attaching the steering cylinder 23 to the front axle 18 is made long, the bolt 77 is passed through the hole of the plate 76, and then the long bolt 77 is attached from the attachment boss 18a of the front axle 18. To project. Then, the protruding portion of the bolt 77 is inserted into the opening of the protrusion 23 a provided on the steering cylinder 23. In this way, the case of the steering cylinder 23 is restricted from rotating toward the axle case 18 via the bolt 77, which serves as a detent for the steering cylinder 23.

Conventionally, a groove (not shown) is provided in the outer peripheral portion of the end of the piston rod 26 of the steering cylinder 23, and a boot that engages with this groove is attached to the end of the piston rod 26. Then, a ball joint 81, which is a connecting member, is connected between the knuckle arm 27 (FIG. 14) on the final case 84, 85 (FIG. 14) side attached to the end portion of the front axle 18 and the end of the piston rod 26 to connect each joint portion. It was covered with boots.

However, when the groove processing is applied to the outer peripheral portion of the piston rod end, the rod end becomes insufficient in strength.

Therefore, the steering cylinder 23 shown in FIG.
Sectional view near the end of FIG. 13A and FIG.
As shown in the arrow A line view, a lock end 26a having a circular cross section, which is a separate member, is screwed into the end of the piston rod 26 via a bolt 26c. As shown in FIG. 13B, the rod end 26a is provided with a pair of recesses 26b, which are partially flat surfaces, on opposing surfaces, and a boot 80 that restricts rotation by partially aligning with the flat surface of the recess 26b. It covers the area around the circular section of the rod end 26a.

The pair of recesses 26b of the rod end 26a have a width corresponding to the diameter of a flat spanner as a tool, and a flat spanner with two flat spanners together with a spanner hooking portion 26d provided at the end of the piston rod 26. Utilizing this, the rod end 26a is firmly tightened with the bolt 26c. The thickness between the recesses 26b, 26b is made larger than the outer diameter of the piston rod 26.

Inside the boot 80, a ball joint 81 which engages with the inner end portion of the circular section of the rod end 26a is inserted. In addition, a large-diameter washer 83 is sandwiched between the inner end surface of the rod end 26a and the outer end surface of the piston 26 to prevent the boot 80 from coming off to the piston rod 26 main body side, and the boot 80 is brought into close contact with the washer 83. Therefore, prevent infiltration of muddy water.

Further, since it is not necessary to form a groove on the outer circumference of the end of the rod end 26a having a circular cross section at the end of the piston rod 26, the end of the piston rod 26 does not become insufficient in strength.

A front wheel drive input case 88 (FIG. 15) is provided at one end of the front axle case 18, an upper final case 84 fixed at both ends, and a king pin (not shown) below the final case 84. A lower final case 85 which is movable in the steering direction and has front wheels 11 attached to the outer side thereof is provided. In the lower final case 85, when the turning angle of the front wheels 11 is steered largely, the wheels 11 may hit the case wall on the front axle 18 side or the front wheel drive input case 88 portion.

Therefore, as shown in the plan view of the main part of the front wheel portion shown in FIG. 14, the perspective view of FIG. 15 and the rear view of FIG. 16, the front wheel drive input case 88 is provided in the vicinity of the joint portion of the final case 84 with the front axle 18. When a swollen portion 84a is provided in the vicinity of the joint with the front wheel 11 and the turning angle of the front wheel 11 is steered by a large amount, the cutting angle stopper bolt 86 attached to the lower final case 85 side is attached to the upper final case 84. It contacts the bulging portion 84a.

Thus, even if the turning angle of the front wheels 11 is steered largely, there is no possibility that the wheels 11 will hit the case wall on the front axle 18 side or the front wheel drive input case 88. In addition, the bulging portion 8 of the final case 84
If 4a is provided symmetrically on the left and right, the front axle 1
The upper final case 84 connected to the left and right ends of 8 can be shared, and the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a side view of a tractor according to an embodiment of the present invention.

2 is a plan view of the tractor of FIG. 1. FIG.

FIG. 3 is a perspective view of a steering post and a power steering unit of the tractor of FIG.

FIG. 4 is a side sectional view of a connecting portion between a steering post and a power steering unit of the tractor of FIG.

5 is a view taken along the line AA of FIG.

FIG. 6 is a side sectional view of a modified example of the connecting portion between the steering post and the power steering unit of the tractor of FIG.

7 is a view taken along the line AA of FIG.

8 is a plan view of a fuel filter installation portion of the tractor of FIG. 1. FIG.

9 is a side view of FIG. 8. FIG.

10 is a rear view of the fuel filter installation portion of the tractor of FIG. 1 (a view taken along the line AA of FIG. 9).

11 is a plan view of a connecting portion between a front axle and a steering cylinder case of the tractor of FIG.

12 is a view taken along the line AA of FIG.

13 is a partial cross-sectional view (FIG. 13A) of a connecting portion between a steering cylinder and a front axle of the tractor of FIG. 1 and a view taken along the line AA of FIG. 13A (FIG. 13B). ).

FIG. 14 is a plan view of a connecting portion between a front axle and a front wheel of the tractor of FIG.

15 is a view from the direction of arrow A in FIG.

16 is a view from the direction of arrow B in FIG. 14 (a rear view of the tractor).

[Explanation of symbols]

1 Main Frame 2 Engine 3 Mission Case 4 Hydrostatic Stepless Transmission (HST) 5 Universal Joint 6 Bonnet 10 Rear Wheel 11 Front Wheel 12 Front Wheel Drive Shaft 14 Mid PTO Shaft 15 Midmoor 16 Parallel Link Mechanism 18 Front Axle (Housing) 18a Bosses 19, 22 Input shafts 20, 24 Universal joint 21 Steering cylinder mounting seat 23 Steering cylinder 23a Protrusion 25 Gear case 26 Piston rod 26a Rod end 26b Recess 26c Bolt 26d Spanner hook 27 Hub case 32 Hydraulic PTO clutch 34 Hydraulic cylinder case 35 Lift Arm 36 Dash Cover 37 Driver's Seat 38 Steering Handle 39 Steering Post 41 Power Steering Unit 41a Flange 41b Bolt Hole 42 Entry / exit floor 43 Fuel filter 45 Housing 46 Handle mounting frame 47 Mounting plate 49 Bracket 49a Steering unit insertion opening 49b Small hole for insertion 50 Radiator mounting plate 50a Side plate 52 Mounting table 53 Reservoir tank mounting plate 56 Handle shaft 57 Hose 58, 77 Bolt 59, 60 Rubber washer 61 Collar 62, 63 Metal washer 66 Stud bolt 67 Assembly nut 70 Floor panel front end attaching / detaching part 72 Connecting plate 76 Plate 80 Boot 81 Ball joint 83 Washer 84, 85 Final case 84a Swelling part 86 Cutting angle stopper bolt 88 Front wheel drive input case

Claims (4)

[Claims] 1. A power steering unit 41 having a flange 41a at the lower end for accommodating a member for power steering is attached to a base portion of a handle shaft 56 having a steering handle 38, and the power steering unit 4 is provided.
The power steering unit 41 is attached to the steering unit 41 insertion opening 49a provided in the bracket 49 of the steering post 39, which is the first supporting member, and the elastic members 59 and 60 arranged above and below the bracket 49 of the steering post 39 are used to A steering handle mounting structure characterized in that a flange 41a of a power steering unit 41 and a bracket 49 of a steering post 39 are fixed to each other. 2. The flange 41a of the power steering unit 41 and the steering post 3 by means of bolts 58.
9. The steering handle mounting structure according to claim 1, wherein the bracket 49 of 9 is fixed via elastic members 59 and 60. 3. The bolt is a power steering unit 41.
The steering handle mounting structure according to claim 2, wherein the stud bolt 66 is fixed to the flange 41 a of the above. 4. The steering post 39 below the floor surface 42 provided at the lower end of the steering post 39.
The steering handle mounting structure according to claim 1, wherein a fuel filter 43 is disposed on an outer surface of a lower end portion of the steering wheel.