JP4976923B2 - Work vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a working vehicle, in which split cases forming a space for mounting a static hydraulic type continuously variable transmission are provided by recessing a part of side walls, thus reducing the lateral widths of the split cases. <P>SOLUTION: A split case unit body 5 includes: an axial plunger 65 of the static hydraulic type continuously variable transmission 6; a swash plate 66; and a guide block 67 to guide inclined motion of the swash plate. At each opposed position of the guide block 67 and the other split case unit body 4, abutting parts 4a, 5a are formed near the center of the space in the split case away from circumferential wall parts of both split case unit bodies 4, 5. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a work vehicle including a case in which a hydrostatic continuously variable transmission is housed in a split case.

  In a combine that is an example of a work vehicle including a case that includes a hydrostatic continuously variable transmission, as disclosed in Patent Document 1, a part of the side wall of the transmission case is recessed to be hydrostatic. Some have a space for the interior of the continuously variable transmission. In this structure, a swash plate is guided by attaching a guide block to the inner back of a space for interior of the hydrostatic continuously variable transmission (see Patent Document 1).

JP 2002-295537 A (paragraphs [0010], [0028], FIGS. 3 and 4)

As in Patent Document 1, in the case where a part of the side wall of the transmission case is recessed to form a space for interiorizing the hydrostatic continuously variable transmission, the outside of the side wall of the transmission case without the recessed part This is useful in that the thickness of the transmission case in the left-right direction can be greatly reduced as compared with a case where a hydrostatic continuously variable transmission is attached.
However, in the continuously variable transmission of hydrostatic, therefore a large load caused by the operation of the plunger in the guide block to guide the swash plate acts, in order to accurately guide the swash plate against the load The thickness of the guide block needs to be set to be considerably thick, and the presence of the thick guide block inside the mission case has been an obstacle to further reducing the lateral width of the mission case.

  According to the present invention, a part of the side wall of the split case is recessed to form a space for housing a hydrostatic continuously variable transmission, and the lateral width of the case can be further reduced. It is an object.

[Solution 1]
As described in claim 1, the work vehicle of the present invention includes a split case formed by joining a plurality of split case units at a mating surface, and a hydrostatic stepless type is provided in the split case. In a work vehicle equipped with a transmission,
On one side of the split case unit, an axial type plunger of a hydrostatic continuously variable transmission, a swash plate for controlling the operation amount of the plunger, and a guide block portion for guiding the tilt of the swash plate,
The guide block portion is provided closer to the mating surface than the plunger and the swash plate,
At the opposite position of the guide block portion and the other divided case unit body, the contact block is formed at a position closer to the center side of the inner space of the case away from the peripheral wall portion of both divided case unit bodies. ,
The contact portion provided at each of the facing portions is formed around the axis of the input shaft or the output shaft of the continuously variable transmission and at a position facing each other across the shaft center. .

[Action and effect]
As described above, in the work vehicle of the present invention according to the solution 1, the inner space of the case that is separated from the peripheral wall portions of the two divided case unit bodies is provided at the opposing positions of the guide block portion and the other divided case unit body. Each contact part is configured to contact by forming the contact part at a position closer to the center side. Therefore, the load of the plunger acting on the guide block portion can also be shared by the other split case unit body provided with a contact portion for abutment to face.
The resulting need not be configured as only strength thick having a withstand alone due to the operation of the plunger load as a guide block, the required strength in cooperation with the other split case unit body The thickness of the guide block part can be made thinner than that of a structure that obtains the required strength alone, and the width of the split case can be reduced. There is.
In addition, the contact portion provided in the guide block portion and the contact portion provided in the other divided case unit body are formed around the axis of the input shaft or the output shaft of the divided case, thereby accompanying the operation of the plunger. A problem that the guide block portion is deformed by a load can be avoided in advance. Therefore, there is an advantage that it is easy to avoid the problem that the unnecessary external force due to the deformation of the guide block portion gives unnecessary resistance to the rotation of the input / output shaft.

[Solution 2]
In the work vehicle according to the second aspect of the present invention, as described in claim 2, the abutting portion is located closer to the inner side in the radial direction than the periphery of the guide block portion around the axis of the input shaft or the output shaft. Is formed.

[Solution 3]
In the work vehicle according to the third aspect of the invention, the contact portion overlaps with a portion where the plunger of the continuously variable transmission is disposed in the axial direction of the input shaft or the output shaft. It is formed within the range.
[Solution 4]
According to a fourth aspect of the work vehicle of the present invention, the contact portion is formed in an arc shape around the axis of the input shaft or the output shaft.
[Solution 5]
According to a fifth aspect of the present invention, the contact portion is formed on the same circumference around the axis of the input shaft or the output shaft.
[Solution 6]
According to a sixth aspect of the present invention, the contact portion is formed on one side and the other side of the input shaft or the output shaft in a direction along the tilting direction of the swash plate. Yes.
[Solution 7]
According to the work vehicle of the present invention, a seal material mounting portion for the outer periphery of the input shaft in the guide block portion is formed on the mating surface side of the guide block portion.

Hereinafter, an example of an embodiment of the present invention will be described based on the drawings.
[Overall configuration of work vehicle]
As shown in FIG. 1, a pre-cutting processing device 2 is disposed on the front side of the body frame 10 supported by a pair of left and right crawler travel devices 1, 1, and a control unit 11 provided on the front side of the body frame 10 is provided. Is arranged behind the control tower (not shown) erected on the front end side of the control unit floor to constitute a combine as an example of the work vehicle of the present invention.
On the rear side of the control unit 11, a threshing device 15 for inheriting the cereals conveyed from the pre-harvest pretreatment device 2 side and holding it with a feed chain 15a, and a threshing processed grain A drain tank processing device 17 for cutting the waste straw discharged from the threshing device 15 is disposed on the rear side.

[Composition of split case]
In this combine, a mission case as an example of a split case is provided between the right and left crawler travel devices 1 on the front side.
As shown in FIG. 2, the mission case 3 has a two-part structure of a right-side divided case unit 4 and a left-side divided case unit 5, and is composed of a combination of both divided case units 4, 5. ing.

  A part of the side wall 50 is formed in a recessed shape on the side of the mating surface 30 of the mission case 3 on the left divided case unit body 5 side in the mission case 3, and the HST case wall 60 is formed by this recessed portion. A hydrostatic continuously variable transmission 6 is housed in a space formed by the HST case wall 60 portion. The open side of the recessed HST case wall 60 is closed by a valve plate 51.

  As shown in FIG. 2, the hydrostatic continuously variable transmission 6 includes a variable displacement hydraulic pump 61 and a hydraulic motor 62. The hydrostatic continuously variable transmission 6 has a neutral stop position, and is configured to be steplessly variable on the forward high speed side and the reverse high speed side.

  An input shaft 19 for inputting engine (not shown) power to the hydraulic pump 61 of the continuously variable transmission 6 projects rightward from the divided case unit 4 on the right side of the transmission case 3, and enters the input shaft 19. An input pulley 19a and a cooling fan 19b are fixed. Power from the engine is transmitted to the continuously variable transmission 6 via a transmission belt (not shown) wound around its output pulley (not shown) and the input pulley 19a of the input shaft 19. It is comprised so that.

As shown in FIG. 2, the transmission gear 64 is fixed to the output shaft 63 of the hydraulic motor 62 of the continuously variable transmission 6, and the transmission gears 32 and 33 are fixed to the intermediate transmission shaft 31 supported by the transmission case 3. The transmission gears 64 and 32 are engaged with each other. A transmission shaft 34 for branching is supported on the transmission case 3, and a transmission gear 33 fixed to the intermediate transmission shaft 31 and a transmission gear 35 fixed to the transmission shaft 34 for branching are engaged with each other.
The right and left side gears 37 are fitted on the branching transmission shaft 34 so as to be relatively rotatable and slidable, and the transmission gear 36 fixed to the right and left axles 38 is engaged with the right and left side gears 37. The drive sprocket 1a (see FIG. 1) of the left crawler travel device 1 is fixed to the ends of the right and left axles 38.

  A pair of left and right side clutches 7 and a pair of left and right side brakes 8 are provided between the branch transmission shaft 34 to which power from the output shaft 63 of the hydraulic motor 62 is transmitted and the left and right axles 38. .

  The side clutch 7 is formed at an end portion of the left and right side gears 37 so as to be engaged with an occlusal portion 34a fixed to the right and left ends of the transmission shaft 34 for branching and at a position facing the occlusal portion 34. Each of the right and left side gears 37, the springs 39 that urge the right and left side gears 37 of the right and left side gears 37 toward the right and left biting parts 34 a of the branch transmission shaft 34, and the right and left side gears 37. It is composed of right and left pistons 49 that can be pushed to move the occlusal portion 37a away from the right and left occlusal portions 34a of the transmission shaft 34 for branching.

  As shown in FIG. 2, the side brake 8 includes a friction plate interposed between left and right side gears 37 that are driven when the side clutch 7 is engaged and side walls 40 and 50 that are fixed portions in the transmission case 3. 80 and the left and right pistons 49 capable of applying a braking force by pressing the friction plate 80.

  In the state shown in FIG. 2, the occlusal portion 37 a of the right side gear 37 is engaged with the right occlusal portion 34 a of the branch transmission shaft 34, and the occlusion portion 37 a of the left side gear 37 is engaged with the left occlusion portion of the branch transmission shaft 34. It is in a state away from 34a. When the right and left side gears 37 are engaged with the right and left occlusal portions 34a of the branching transmission shaft 34 by the biasing force of the spring 39, the power of the intermediate transmission shaft 31 is transmitted to the transmission gear 33 and the transmission gear 35 of the branching transmission shaft 34. The aircraft is transmitted straight to the right and left axles 38 via the branching transmission shaft 34, the right and left occlusion portions 34 a of the branching transmission shaft 34, and the occlusion portions 37 a of the right and left side gears 37.

The input shaft 19 to which the engine power is input is located in the middle of the input shaft 19 that transmits power to the continuously variable transmission 6 provided inside the HST case wall 60 and to the right of the bottom surface of the HST case wall 60. A work gear branching transmission gear 20 is provided at a position corresponding to the split case unit 4 side to extract power to the pre-cutting processing device 2 side.
In the transmission system for the output pulley 26 for outputting the power of the cutting pretreatment device 2, the transmission shaft 21 is supported by the transmission case 3 and the transmission gears 22, 23 are supported by the transmission shaft 21, as shown in FIG. Is fixed, and the transmission gear 20 and the transmission gear 22 fixed to the input shaft 19 are engaged with each other. The transmission shaft 25 is supported by the transmission case 3, the transmission gear 24 fixed to the output shaft 25 is engaged with the transmission gear 23, and the power of the input shaft 19 is transmitted to the output shaft 25 via the transmission shaft 21. It is configured to be transmitted to the cutting unit 2 via an output pulley 26 fixed to the output shaft 25 and a transmission belt (not shown).

[Composition of the contact section]
In the work vehicle including the transmission case configured as described above, in the present invention, the following configuration is added to the left and right divided case units 4 and 5.
As shown in FIG. 3, a swash plate 66 that controls the operation amount of the axial plunger 65 is provided on the bottom surface side of the HST case wall 60 that houses the hydrostatic continuously variable transmission 6 in the left divided case unit 5. A guide block 67 is provided to guide the tilting.
The guide block 67 is disposed at a position closer to the mating surface 30 side of the transmission case 3 than the plunger 65 and the swash plate 66, and on the other side, that is, on the right divided case unit 4 side. A contact portion 5a that contacts the portion 4a is integrally formed.

The guide block contact portion 5a is formed in 67 and the right side of the split case the unit body 4 contact portion 4a formed on the side, is 4, it is formed in an area indicated by hatching in FIG. In other words, the left split case unit 5 includes a peripheral wall 52 portion along the outer shape thereof, and the mating surface 30 is formed at the end of the peripheral wall 52 on the side facing the right split case unit 4. Yes.
The contact portion 5a formed on the guide block 67 is formed flush with the mating surface 30 portion formed at the end of the peripheral wall 52 portion along the outline shape of the divided case unit body 5. However, as can be seen from the hatched region shown in FIG. 4, it is not in the so-called peripheral wall 52 part, but is formed in a state where it enters the space part inside the case surrounded by the peripheral wall 52.

The contact portion 5a is formed in a partial arc shape around the axis of the input shaft 19 that transmits power to the continuously variable transmission 6, outside the transmission gear 20 fixed to the input shaft 19, and along the periphery of the guide block 67 portion. Is formed.
In the example shown in FIG. 3, the contact portion 5 a is formed so that the input shaft 19 has a shape along the outer periphery of both the transmission gear 20 fixed to the input shaft 19 and the transmission gear 22 meshing with the transmission gear 20. It is formed in a partial arc shape formed by a partial arc along the axis of 19 and a partial arc along the axis of the transmission shaft 21, and is provided on the peripheral portion of the guide block 67.

The contact portion 4a formed on the right divided case unit 4 side is symmetrical with respect to the contact portion 5a provided on the guide block 67 with the mating surface 30 of the mission case 3 as a boundary. It is formed in the position. Therefore, as shown by hatching in FIG. 5, it is not in the so-called peripheral wall 42 portion but in a state of entering the space portion on the inner side of the case surrounded by the peripheral wall 42. Also in this contact portion 4 a, the contact portion 4 a is formed flush with the mating surface 30 portion formed at the end of the peripheral wall 42 portion along the outline shape of the divided case unit body 4.
As shown in FIG. 6, the center hole 67 a through which the input shaft 19 of the guide block 67 can be inserted is provided with a seal material mounting portion 68 opened to the mating surface 30 side. The sealing material mounting portion 68 is formed only in a portion of the central hole 67a closer to the mating surface 30 and is not formed on the side facing the swash plate 66.

[Another Embodiment of the Invention]
[1] The contact portion 5 a provided in the guide block 67 and the contact portion 4 a formed on the side of the divided case unit 4 at a position facing the contact portion 5 a are not necessarily flush with the mating surface 30 of the mission case 3. However, it may be provided at a position slightly deviated from the mating surface 30 toward one of the divided case unit bodies.
Further, when the contact portions 4a and 5a extend to a plurality of locations, the contact portions 4a and 5a enter the divided case unit body side on the side where one contact portion faces, and the other contact portion faces the opposite side. It may be one in which the raised height is individually set so as to enter the divided case unit body side.

[2] The contact portions 4a and 5a are not limited to those provided around the axis of the input shaft 19 of the continuously variable transmission 6, but around the axis of the output shaft 63 of the continuously variable transmission 6 or the input shaft. 19 and the output shaft 63 may be provided around the respective axis centers.

[3] When a hydrostatic continuously variable transmission 6 is used as a transmission of the pre-cutting device, and the continuously variable transmission 6 is mounted in a case (divided case), the case (divided case) The invention may be applied.
The present invention may be applied not only to a combine, but also to a farm vehicle such as an agricultural tractor, a mower, or a paddy field work machine such as a riding rice transplanter, or a construction vehicle such as a wheel loader.

Combine side view Longitudinal front view of the mission case Longitudinal front view of the top of the mission case Exploded side view showing the split case unit on the left side of the mission case Exploded side view showing the split case unit on the right side of the mission case Longitudinal front view showing the disassembled state of the mission case Exploded side view showing the upper part of the split case unit on the left side of the mission case

3 Mission Case 4 Right Split Case Unit Body 5 Left Split Case Unit Body 4a, 5a Contact Part 6 Continuously Variable Transmission 19 Input Shaft 30 Matching Surface 42, 52 Perimeter Wall 65 Plunger 66 Swash Plate 67 Guide Block

Claims (7)

A work vehicle comprising a split case formed by joining a plurality of split case units together at a mating surface, and having a hydrostatic continuously variable transmission installed in the split case,
On one side of the split case unit, an axial type plunger of a hydrostatic continuously variable transmission, a swash plate for controlling the operation amount of the plunger, and a guide block portion for guiding the tilt of the swash plate,
The guide block portion is provided closer to the mating surface than the plunger and the swash plate,
At the opposite position of the guide block portion and the other divided case unit body, the contact block is formed at a position closer to the center side of the inner space of the case away from the peripheral wall portion of both divided case unit bodies. ,
The contact portion provided at each of the facing portions is formed around the axis of the input shaft or the output shaft of the continuously variable transmission and at a position facing each other across the shaft center. Work vehicle. 2. The work vehicle according to claim 1, wherein the contact portion is formed at a position closer to an inner side in a radial direction than a peripheral edge of the guide block portion around an axis of the input shaft or the output shaft. 3. The work vehicle according to claim 1, wherein the contact portion is formed within a range overlapping with a portion where the plunger of the continuously variable transmission is disposed when viewed in the axial direction of the input shaft or the output shaft. . The work vehicle according to claim 1, wherein the contact portion is formed in an arc shape around an axis of the input shaft or the output shaft. The work vehicle according to claim 1, wherein the contact portion is formed on the same circumference around an axis of the input shaft or the output shaft. The work vehicle according to any one of claims 1 to 5, wherein the contact portion is formed on one side and the other side of the input shaft or the output shaft in a direction along a tilting direction of the swash plate. The work vehicle according to claim 1, wherein a seal material mounting portion for the outer periphery of the input shaft in the guide block portion is formed on the mating surface side of the guide block portion.

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