WO2015108105A1

WO2015108105A1 - Work vehicle

Info

Publication number: WO2015108105A1
Application number: PCT/JP2015/050935
Authority: WO
Inventors: 福元　健氏
Original assignee: ヤンマー株式会社
Priority date: 2014-01-17
Filing date: 2015-01-15
Publication date: 2015-07-23

Abstract

The purpose of the present invention is to provide a work vehicle which is capable of easily ensuring the ability to travel forward and rearward on a bad road or through a wet paddy field in which a traveling crawler (49) would be prone to sinking. This work vehicle is equipped with a traveling machine body (2) in which an engine (5) is mounted, a track frame (37) provided on the bottom side of the rear section of the traveling machine body (2), and a traveling crawler (49) to be mounted to the track frame (37). A structure equipped with an equalizer track roller (50) for supporting the traveling crawler (49) on the rear-end side of the track frame (37) is configured in a manner such that the angle of recession of the traveling crawler (49) supported by the equalizer track roller (50) is similar to the path of the outer diameter of a traveling vehicle wheel.

Description

Work vehicle

The present invention relates to a work vehicle such as a tractor in which left and right traveling crawlers are installed in the rear part of an airframe equipped with an engine or the like.

As shown in

Patent Documents

1 and 2, left and right traveling crawlers are installed at the lower part of a traveling vehicle body such as a tractor, and the front end side of the track frame is fixed to the front portion of the traveling vehicle body, and a rear axle case or the like. There is a prior art in which a rear end side of a track frame is fixed to a rear portion of the traveling machine body, and a traveling crawler is supported on the traveling machine body via the track frame. In addition, as shown in Patent Documents 3 to 5, the left and right front wheels are installed in the front part of the aircraft, and the left and right traveling crawlers are installed in the rear part of the aircraft. The travel part is pivotally mounted on the side of the traveling vehicle body such as the rear axle case by a single fulcrum fulcrum shaft disposed at an appropriate distance below the rear axle, and a traveling crawler (track frame) There is also a prior art in which the front part and the rear part move up and down in opposite directions.

JP 2007-118907 A JP 2008-49866 A Japanese Patent Laid-Open No. 10-45051 JP 2006-96199 A JP 2004-217054 A No. 6-3748

In the prior arts of

Patent Documents

1 and 2, since the track frame is integrally fixed to the traveling machine body, when the traveling machine body tilts back and forth, the track frame tilts back and forth integrally with the traveling machine body. Thus, the inclination angle in the front-rear direction of the ground contact surface of the traveling crawler is likely to increase, and it is not only possible to maintain a good riding comfort for the operator riding on the control seat, but also the traveling driving force (running force) of the traveling crawler varies. There are problems such as. Further, in the prior arts of Patent Documents 3 to 5, since the track frame is supported on the traveling machine body by one-point support by the swing fulcrum shaft, there is a problem that the load is concentrated on the swing fulcrum shaft. In addition, when the front driven wheel is moved back and forth to adjust the tension of the traveling crawler, there is a problem that the ground contact angle at the front of the traveling crawler tends to change. In addition, as shown in Patent Document 6 and the like, there is a prior art in which a traveling crawler is mounted on the track frame via a wheel, and a seal is provided on a bearing portion of the wheel.

Therefore, the present invention seeks to provide a work vehicle such as a tractor that has been improved by examining these current conditions.

In order to achieve this technical problem, a first aspect of the present invention provides a work vehicle including a traveling machine body on which an engine is mounted, a track frame provided at a rear lower side of the traveling machine body, and a traveling crawler attached to the track frame. In the above structure, an equalizer wheel that supports the traveling crawler is provided on the rear end side of the track frame, and a reverse angle of the traveling crawler supported by the equalizer wheel approximates an outer diameter locus of the traveling wheel. It is comprised as follows.

According to a second aspect of the present invention, in the work vehicle according to the first aspect, the structure includes an axle that drives the traveling crawler and a driving sprocket, and the traveling is performed via an arm that is pivotally supported on an axis of the axle. The rear end side of the track frame is connected to the airframe.

According to a third aspect of the present invention, in the work vehicle according to the first aspect, the track frame is formed by a front track frame and a rear track frame that can be expanded and contracted.

According to a fourth aspect of the present invention, in the work vehicle according to the third aspect of the present invention, a front arm and a rear arm are arranged in a C shape in a side view between the traveling machine body and the front track frame or the rear track frame. .

According to a fifth aspect of the present invention, in the work vehicle according to the first aspect, a labyrinth ring groove is formed on an outer periphery of a boss portion of the equalizer wheel, and a labyrinth ring is fitted into the labyrinth ring groove. .

According to a sixth aspect of the present invention, in the work vehicle according to the fifth aspect, a support shaft is rotatably supported by a bearing cylinder of the track frame via a bearing bearing, and a wheel is provided at an end of the support shaft. In this structure, the bearing retaining member is inserted on the inner peripheral side of the bearing cylinder, and the labyrinth ring is slidably contacted with the shaft hole surface of the bearing retaining member.

A seventh aspect of the invention is the work vehicle according to the fifth aspect, wherein the equalizer wheel is formed by casting, and the bearing retaining member is made of a softer material than the wheel. Formed.

The invention according to claim 8 is a work vehicle including a traveling machine body on which an engine is mounted, a track frame provided below the traveling machine body, and a traveling crawler attached to the track frame, wherein the track frame is a front track frame. The rear track frame is divided and formed, and the front end side of the rear track frame is slidably connected to the rear end side of the front track frame, and the front driven wheel and the front wheel are arranged on the front end side of the front track frame. A rear driven wheel and a rear wheel are arranged on the rear end side of the track frame.

According to a ninth aspect of the present invention, in the work vehicle according to the eighth aspect of the present invention, the rear track frame, the rear driven wheel body, and the rear wheel are rotatably supported around the axle of the traveling machine body. is there.

According to a tenth aspect of the present invention, in the work vehicle according to the eighth aspect, a front track frame is connected to the traveling machine body via a front arm, and the front arm rotates to move the front track frame and the front driven wheel. The body and the front wheel are configured to move in the front-rear direction.

The invention according to claim 11 is the work vehicle according to claim 8, wherein a rear track frame is connected to the traveling machine body via a rear arm, and the rear arm is connected to the rear track frame via a fulcrum receiving bracket. And attaching a rear wheel to the fulcrum support bracket, and providing a spring support bracket body on the front track frame, and a tension adjusting mechanism for the traveling crawler via the spring support bracket body between the front track frame and the rear track frame The tension spring is arranged, and a front rolling wheel is attached to the spring receiving bracket body.

According to claim 1, in a work vehicle comprising a traveling machine body on which an engine is mounted, a track frame provided on a lower rear side of the traveling machine body, and a traveling crawler attached to the track frame, on a rear end side of the track frame. The structure is provided with an equalizer wheel that supports the traveling crawler, and the receding angle of the traveling crawler supported by the equalizer wheel is configured to approximate the outer diameter locus of the traveling wheel. It is possible to easily ensure backward running performance on wet fields or rough roads where the traveling crawler tends to sink, and to easily improve the direction change workability at the time of pillow in the field.

According to claim 2, a structure including an axle for driving the traveling crawler and a drive sprocket, the rear end side of the track frame being connected to the traveling aircraft body via an arm that is pivotally supported on the axis of the axle. As a result, the track frame rotates around the axle and the equalizer wheel is displaced so that the traveling crawler is retracted properly with respect to the traveling crawler moving forward and downward. Can be maintained.

According to the third aspect, since the track frame is formed by the front track frame and the rear track frame that can be expanded and contracted, the tension of the traveling crawler can be properly maintained by the back and forth movement of the front track frame. For example, the traveling crawler can be tension-supported by utilizing the weight of the vehicle body and the following performance of the traveling crawler with respect to unevenness on the traveling road surface can be improved.

According to claim 4, since the front arm and the rear arm are arranged between the traveling machine body and the front track frame or the rear track frame in a C shape in a side view, And the tension of the traveling crawler can be maintained using the weight of the vehicle body.

According to claim 5, a labyrinth ring groove is formed on the outer periphery of the boss portion of the equalizer wheel, and a labyrinth ring is fitted into the labyrinth ring groove. It is not necessary to add grease, and troubles such as leakage of the grease can be eliminated, and maintenance work such as replenishment of the grease can be simplified.

According to a sixth aspect of the present invention, there is provided a structure in which a support shaft is rotatably supported by a bearing cylinder of the track frame via a bearing bearing, and a wheel is fastened and fixed to an end portion of the support shaft. Since the bearing retaining body is inserted into the inner peripheral side of the bearing and the labyrinth ring is slidably contacted with the shaft hole surface of the bearing retaining body, the bearing bearing structure can be simplified, The waterproof function of the labyrinth ring can be easily improved.

According to claim 7, since the equalizer roller is formed by casting, and the bearing retaining member is formed of a softer material than the equalizer roller, aluminum die casting Alternatively, the bearing retaining body can be formed of synthetic resin or the like, and rust prevention of the bearing retaining body can be eliminated.

According to an eighth aspect of the present invention, in a work vehicle including a traveling machine body on which an engine is mounted, a track frame provided on a lower side of the traveling machine body, and a traveling crawler attached to the track frame, the track frame is disposed on the front and rear truck frames. The track frame is divided and formed, and the front end side of the rear track frame is slidably connected to the rear end side of the front track frame, and the front driven wheel and the front wheel are arranged on the front end side of the front track frame. Since the rear driven wheel body and the rear rolling wheel are arranged on the rear end side of the frame, the traveling crawler is moved forward and backward by the front driven wheel body without changing the ground contact angle of the front portion of the traveling crawler. While being able to support the appropriate tension and easily improve the traveling performance of the traveling crawler, La can be suppressed before and after tilting of the ground surface), can maintain a good ride comfort of the operator who boarded the control seat.

According to the ninth aspect, since the rear track frame, the rear driven wheel body, and the rear wheel are rotatably supported around the axle of the traveling machine body, the track frame (of the traveling crawler) is configured. The grounding width of the traveling crawler can be changed based on the rear part of the traveling crawler, and the grounding pressure of the traveling crawler can be easily changed. Can be suppressed.

According to the tenth aspect, the front track frame is connected to the traveling machine body via the front arm, and the front arm rotates to move the front track frame, the front driven wheel body, and the front wheel in the front-rear direction. Thus, the forward and backward tilting of the track frame (the ground contact surface of the traveling crawler) can be suppressed, and the tension of the traveling crawler can be appropriately maintained using the weight of the vehicle body such as the traveling machine body. .

According to the eleventh aspect of the present invention, the rear track frame is connected to the traveling vehicle body via a rear arm, the rear arm is connected to the rear track frame via a fulcrum receiving bracket, and a rear wheel is connected to the fulcrum receiving bracket. On the other hand, a spring receiving bracket body is provided on the front track frame, a tension spring of the tension adjusting mechanism for the traveling crawler is disposed between the front track frame and the rear track frame via the spring receiving bracket body, and the spring receiving bracket Since the front rolling wheel is attached to the body, the rear rolling wheel can be supported by using the fulcrum receiving bracket to simplify the track frame support structure, and the front rolling wheel can also be used by combining the spring receiving bracket body. By supporting the wheel, the traveling crawler tension structure can be simplified.

It is a side view of the tractor in a 1st embodiment. It is the same top view. It is a side view of a crawler traveling device. It is a top view of the same part. It is expansion explanatory drawing of the rear part of a crawler traveling apparatus. It is the elements on larger scale of a track frame. It is sectional explanatory drawing of the track frame rear part. It is sectional explanatory drawing of the track frame front part. It is a section explanatory view of a wheel. FIG. 10 is an enlarged explanatory view of FIG. 9. It is a perspective view of a track frame support part. It is a side view of the tractor in 2nd Embodiment. It is the same top view. It is a side view of a crawler traveling device. It is a top view of the same part. It is expansion explanatory drawing of the rear part of a crawler traveling apparatus. It is the elements on larger scale of a track frame. It is sectional explanatory drawing of the track frame rear part. It is sectional explanatory drawing of the track frame front part. It is a section explanatory view of a wheel. It is expansion explanatory drawing of FIG. It is a perspective view of a track frame support part.

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings (FIGS. 1 to 11). First, the agricultural tractor 1 will be described with reference to FIGS. A farm tractor 1 as a work vehicle shown in FIGS. 1 to 4 is configured to perform a tilling work for plowing a farm field by attaching a tilling work machine 31 and the like via a hydraulic lift mechanism 30. 1 is a left side view of the tractor 1, FIG. 2 is a plan view thereof, FIG. 3 is a side view of the crawler traveling device, and FIG. 4 is a plan view of the same portion. In the following description, the left side in the forward direction of the tractor 1 is simply referred to as the left side, and the right side in the forward direction is also simply referred to as the right side.

As shown in FIGS. 1 to 4, a farm tractor 1 as a work vehicle supports a traveling machine body 2 with a pair of left and right crawler traveling devices 3, and a diesel engine 5 is mounted on the front part of the traveling machine body 2. The crawler traveling device 3 is driven by the engine 5 so as to travel forward and backward. The upper surface side and the left and right side surfaces of the diesel engine 5 are covered with an openable / closable bonnet 6.

In the upper surface of the traveling machine body 2, behind the bonnet 6, a driving cabin 7 is installed as a driving unit on which an operator gets on. Inside the cabin 7 is provided a front column 10 including a control seat 8 on which an operator sits, a control handle 9 as steering means, and the like. The front column 10 is provided with left and right brake pedals, clutch pedals, shift pedals, forward / reverse switching levers, and the like as steering devices.

Further, the traveling machine body 2 includes a transmission case 17 that transmits the output of the diesel engine 5 by the transmission shaft 16, and shifts the output from the diesel engine 5 and transmits it to the crawler traveling device 3. At the rear of the mission case 17, a tiller 31 and the like can be moved up and down via a traction mechanism 21 such as a left and right lower link 18, a top link 19, and a left and right lift arm 20 provided in a hydraulic lift mechanism 30. The PTO shaft 22 provided on the rear side surface of the transmission case 17 is driven by the tilling work machine 31 so that the tilling work can be performed. Furthermore, the traveling machine body 2 of the tractor 1 includes a diesel engine 5, a transmission case 17, a vehicle body frame 23 that connects them, a front chassis 24 that extends forward from the diesel engine 5, and the like. The front loader 32 can be attached to the front portion of the agricultural tractor 1 (the traveling machine body 2), and the bucket 33 of the front loader 32 is operated up and down so that the loader work can be executed.

1 to 7 and 11, left and right rear axle cases 34 are provided on both the left and right sides of the mission case 17, respectively. The crawler traveling device 3 is detachably attached to the traveling machine body 2 and the rear axle case 34. One end of the rear axle 35 is pivotally supported in the rear axle case 34, and then a reduction final gear (not shown) is pivotally supported on one end of the axle 35. The other end side of the rear axle 35 is protruded from the rear axle case 34, and then a driving wheel body 36 is attached to the other end side of the axle 35. On the other hand, a track frame 37 extending in the front-rear direction is disposed below the rear axle case 34. The arm support member 38 is detachably fastened to the traveling machine body 2. A front arm 39 pivotally supported on the arm support member 38 and a rear arm 40 pivotally supported on the rear axle case 34 are provided. The

arms

39 and 40 are mounted on the traveling machine body 2 and the transmission case 17. Thus, the track frame 37 is connected to the rear axle case 34 so as to be rotatable (back and forth).

As shown in FIG. 1 to FIG. 8 and FIG. 11, the track frame 37 is divided into a front track frame 41 and a rear track frame 42, and a connecting frame 43 is fixed to the front portion of the rear track frame 42. A rear portion of the front track frame 41 is supported by a front portion of the frame 42 via a connecting frame 43 so as to be slidable in the front-rear direction. A tension adjusting mechanism 44 is disposed on the upper surface of the connecting frame 43, and the front track frame 41 and the rear track frame 42 are connected to each other by the tension adjusting mechanism 44 so as to extend and contract.

Further, the front driven wheel body 46 is attached to the front end side of the front track frame 41 via the front support shaft 45. A rear driven wheel body 47 is attached to the rear end side of the track frame 37 by a rear support shaft 48. A synthetic crawler traveling crawler 49 serving as a crawler belt is wound around the driving wheel body 36, the front driven wheel body 46, and the rear driven wheel body 47 in a substantially triangular shape. A pair of left and right front arms 39 and a pair of left and right rear arms 40 for supporting a pair of left and right track frames 37 on the traveling machine body 2 are provided, and a pair of left and right traveling crawlers 49 are independently suspended. The driving wheel body 36 (rear axle 35) is rotated forward or backward at an appropriate speed and the traveling crawler 49 is driven forward or backward to drive the traveling machine body 2 forward or backward. ing.

In addition, two sets of equalizer members 51 on which two wheels 50 are pivotally supported are provided, and two sets of equalizer members 51 are pivotally supported on the rear track frame 42. Two sets of four rolling wheels 50 are rotatably provided on the rear track frame 42. Of the inner peripheral surface of the traveling crawler 49, a plurality of wheels 50 are brought into contact with the inner peripheral surface between the front driven wheel body 46 and the rear driven wheel body 47 (the inner peripheral surface on the ground contact side of the traveling crawler 49). Let The plurality of wheels 50 are configured to support the landing side of the traveling crawler 49 on the ground.

As shown in FIGS. 3 to 8 and 11, the front equalizer member 51 is supported on the front end portion of the connecting frame 43 via the fulcrum shaft 52, and the fulcrum receiving bracket 53 is disposed on the rear end portion of the rear track frame 42. Then, the rear equalizer member 51 is supported by the fulcrum receiving bracket 53 via the fulcrum shaft 54. The upper end side of the rear arm 40 is pivotally supported by the rear axle case 34, and the lower end side of the rear arm 40 is detachably fastened and fixed to the fulcrum receiving bracket 53 by a bolt 55. That is, the rear arm 40 is erected in a substantially vertical posture through the fulcrum receiving bracket 53 at the rear end portion of the rear track frame 42. The left and right rear arms 40 are disposed so as to be rotatable around the left and right rear axles 35, and the rear end side of the track frame 37 is connected to the traveling machine body 2 via the rear arms 40 that are pivotally supported on the axis of the rear axle 35. The retreat angle of the traveling crawler 49 supported by the equalizer wheel 50 disposed on the rear end side of the track frame 37 is configured to approximate the outer diameter locus of a general traveling wheel supported on the rear axle 35. is doing.

On the other hand, the upper end side of the front arm 39 is pivotally supported on the arm support member 38 on the outer side surface of the body frame 23 via the upper end pivot shaft 60, and the lower end is pivotally mounted on the inner side surface of the front track frame 41. A lower end side of the front arm 39 is pivotally supported via a shaft 61 so that the front arm 39 is supported in a rearward inclined posture between the vehicle body frame 23 and the front track frame 41. The connecting portion (lower end pivot shaft 61) between the track frame 37 and the front arm 39 is disposed closer to the front portion of the traveling crawler 49 than the connecting portion (upper end pivot shaft 60) between the traveling machine body 2 and the front arm 39. When a lower end pivot shaft 61 is disposed in front of the upper end pivot shaft 60 and the ground pressure (tension force) of the traveling crawler 49 changes, the front arm 39 rotates around the upper pivot shaft 60, and the front arm 39, the lower end side of the rear arm 40 is moved directly below the rear axle 35 as the circumferential length of the traveling crawler 49 becomes longer with time. It is configured to shift from the initial state of the suspended substantially vertical posture to the forward inclined posture displaced to the rear side of the rear axle 35. That is, when the front and rear lengths of the front track frame 41 and the rear track frame 42 are increased, the front arm 39 and the rear arm 40 are supported in a C shape in a side view with respect to the traveling machine body 2.

With the above configuration, the front arm 39 and the rear arm 40 are arranged in a letter C shape between the traveling body 2 and the front track frame 41 or the rear track frame 42. When the rear arm 40 rotates around the rear axle case 34 due to the movement, and the grounding posture of the traveling crawler 49 changes to the forward leaning posture or the backward leaning posture, for example, the farm field performing the tilling work is in contact with the traveling crawler 49. In the case of a wetland where the amount of ground subsidence increases, the traveling crawler 49 is supported in a forwardly raised position, the angle of attack of the front part of the traveling crawler 49 is increased, and the traveling crawler 49 is in a forwardly lowered (backwardly raised) position. As a result, the angle of attack of the rear portion of the traveling crawler 49 is increased, the fluctuation of the pitching of the traveling body 2 is suppressed, and the operation of the control seat 8 is suppressed. It is possible to reduce the before and after tilting of the data. Further, when the front track frame 41 and the rear track frame 42 are expanded and contracted due to the rotation of the front arm 39, for example, when traveling on an uneven road surface, the ground contact surface of the traveling crawler 49 is It can be deformed following the uneven road surface, and the body vibration accompanying traveling on the uneven road surface can be reduced. Therefore, the ride comfort of the operator who has boarded the control seat 8 can be maintained in a good state.

In other words, the front track frame 41 and the rear track frame 42 are based on the weight of the vehicle body 2 on the side of the traveling machine body 2 to which the tilling work machine 31 or the front loader 32 is detachably attached, or the amount of settlement of the traveling crawler 49 in the wet field. The track frame 37 (the front track frame 41 and the rear track frame 42) is in a forwardly raised posture or a forwardly lowered posture due to running resistance during forward movement or reverse movement, etc. Therefore, while the tension of the traveling crawler 49 can be maintained substantially constant, the angle of attack of the traveling crawler 49 is ensured at an appropriate angle adapted to the traveling conditions, and the traveling crawler 49 is moved forward or backward. Runability can be improved. It is possible to easily prevent the traveling crawler 49 from being turned forward or rearward and increasing the running resistance.

Therefore, when the tractor 1 is caused to travel forward, the traveling crawler 49 receives the forward reaction force from the ground, whereby the track frame 37 is rotated forward around the rear axle 35, and the traveling crawler 49 is inclined to the forwardly raised posture. And move forward. On the other hand, when the tractor 1 is driven backward, by receiving a reverse reaction force from the ground, the track frame 37 is rotated backward around the rear axle 35, and the traveling crawler 49 is inclined in a forward-downward posture to move backward. Moving.

Next, the structure of the track frame 37 and the tension adjusting mechanism 44 will be described with reference to FIG. As shown in FIG. 6, the tension adjusting mechanism 44 has an outer cylinder 65 fixed to the upper surface of the front part of the connection frame 43 (rear track frame 42), and can be freely inserted into and removed from the inner space of the outer cylinder body 65 through the front opening. An inner cylinder 66 to be inserted, a support plate 67 that closes the rear opening of the outer cylinder 65, a tension bolt 68 that is rotatably supported by the support plate 67, and a tension bolt 68 that extends inside the inner cylinder 66. A slide cylinder 69 screwed onto the tension screw portion, a tension spring seat 70 fixed to the rear end side of the slide cylinder 69, a spring receiving bracket body 71 raised on the upper surface of the front track frame 41, and an inner cylinder And a tension spring 72 provided between the front end portion of 66 and the tension spring seat 70. Between the front track frame 41 and the rear track frame 42, a slide cylinder 69 as a tension rod and a tension spring 72 are arranged. Further, as shown in FIG. 8, the upper surface of the outer cylindrical body 65 is inclined so that the left and right ends are lowered, and the upper surface of the outer cylindrical body 65 is formed in a mountain shape (roof shape). The amount of mud that accumulates on the top surface is reduced.

As shown in FIG. 6, a tension spring 72 is wound and supported on the outer peripheral side of the slide cylinder 69 in a loose fit. A tension spring seat 70 is connected to a tension screw portion of the tension bolt 68 via a slide cylinder 69. The ends of the tension bolts 68 are projected outward from the rear side of the support plate 67 (outer cylinder 65). An idling prevention nut body 73 is screwed onto the protruding end thread portion of the tension bolt 68. The angular head 68a for rotation operation is formed on the protruding end screw portion of the tension bolt 68. Further, the front end side of the slide cylinder body 69 is slidably projected in front of the inner cylinder body 66 and the spring receiving bracket body 71, and the elastic rubber stopper 74 is fitted on the front end portion of the slide cylinder body 69. The front end side of the elastic pressure stopper body 74 is fixed to the slide cylinder 69 via the bolt 75 and the seat plate body 76, and the rear end side of the elastic pressure stopper body 74 is brought into contact with the front side of the spring receiving bracket body 71.

That is, the rear end side of the tension bolt 68 is fixedly supported on the support plate 67 and the tension spring 72 is received by the tension spring seat 70. As a part of the extendable front track frame 41 that supports the front driven wheel body 46, an inner cylinder body 66 and a spring receiving bracket body 71 are provided. The front and rear lengths of the outer cylinder body 65 and the inner cylinder body 66 (front and rear lengths of the front track frame 41 and the rear track frame 42) are extended by the tension spring 72 so that the tension of the traveling crawler 25 is maintained substantially constant. It is composed. Further, an elastic pressure stopper body 74 is pressure-bonded to the front side of the spring receiving bracket body 71 provided at the front end portion of the slide cylinder body 69 by a tension spring 72, and the tension spring 72 and the elastic pressure stopper body on the slide cylinder body 69 are pressed. The spring receiving bracket body 71 is clamped at 74, and the slide cylindrical body 69 is slidably supported by the spring receiving bracket body 71 so as to be slidable. Therefore, the front and rear lengths of the front track frame 41 and the rear track frame 42 change due to elastic deformation of the tension spring 72 and the elastic pressure stopper body 74, and the tension of the traveling crawler 25 is maintained substantially constant.

When the tension of the traveling crawler 49 is reduced, a rotation operation tool (not shown) is locked to the rotation operation square head 68a with the idling prevention nut 73 loosened, and the rotation operation tool is used. The tension bolt 68 is rotated to change the connection length between the tension bolt 68 and the slide cylinder 69, and the tension spring 72 is adjusted by the tension bolt 68 to keep the tension of the traveling crawler 49 constant.

As shown in FIGS. 1 to 8 and 11, a work vehicle including a traveling machine body 2 on which the engine 5 is mounted, a track frame 37 provided on the lower rear side of the traveling machine body 2, and a traveling crawler 49 attached to the track frame 37. The track frame 37 is divided into a front track frame 41 and a rear track frame 42, the front track frame 41 is connected to the traveling machine body 2 via a front arm 39, and the rear track 40 is connected to the traveling machine body 2 via a rear arm 40. The frame 42 is connected, and the front track frame 41 and the rear track frame 42 are connected to be extendable. Therefore, the front track frame 41 and the rear track frame 42 can be extended by the weight of the vehicle body, and the traveling crawler 49 can be supported with appropriate tension, and the traveling performance of the traveling crawler 49 can be easily improved. Further, even when the traveling machine body 2 tilts back and forth, the forward and backward tilting of the track frame 37 (the ground contact surface of the traveling crawler 49) can be suppressed, and a good ride comfort for the operator who has boarded the control seat 8 can be maintained.

As shown in FIGS. 2 to 8, a rear arm 40 is rotatably arranged on the rear axle case 34 of the traveling machine body 2. Therefore, the front and rear ground contact width of the traveling crawler 49 can be changed with the rear portion of the traveling crawler 49 as a reference, and fluctuations in the ground contact pressure of the traveling crawler 49 can be easily suppressed.

As shown in FIGS. 2 to 8, the front arm 39 and the rear arm 40 are arranged in a letter C shape between the traveling body 2 and the track frame 37 in a side view. Therefore, a spring body that is elastically pressed against the front arm 39 can be eliminated, and the tension of the traveling crawler 49 can be maintained by utilizing the weight of the vehicle body.

As shown in FIGS. 2 to 8, the rear arm 40 is connected between the traveling machine body 2 and the track frame 37 in a substantially vertical position, while the front arm 39 is connected between the traveling machine body 2 and the track frame 37 in a backward tilted position. I am letting. Therefore, the front arm 39 can be tilted by the weight of the vehicle body in the direction in which the traveling crawler 49 is tensioned, and the tension structure of the traveling crawler 49 can be simplified.

As shown in FIGS. 1 to 8 and 11, a work vehicle including a traveling machine body 2 on which the engine 5 is mounted, a track frame 37 provided on the lower rear side of the traveling machine body 2, and a traveling crawler 49 attached to the track frame 37. In the structure, a tension spring 72 for tensioning the traveling crawler 49 is provided, and an elastic stopper body 74 for restricting the extension side of the tension spring 72 is provided. The traveling crawler is formed by extension of the tension spring 72 and deformation of the elastic stopper body 74. 49 is configured to be tensioned. Therefore, when the traveling crawler 49 is extended (tensioned) by the repulsive force of the compression spring of the tension spring 72, excessive tension of the traveling crawler 49 can be prevented by the elastic stopper body 74, and the tension spring 72 and the elastic stopper body 74 are separated. It can also be used as a suspension, improving the ride comfort of the operator.

As shown in FIGS. 2 to 8, the track frame 37 is divided into a front track frame 41 and a rear track frame 42 so as to be extendable and contracted, and the extension operation of the front track frame 41 and the rear track frame 42 is applied to an elastic stopper 74. Are regulated. Therefore, the tension of the traveling crawler 47 can be changed by the linear motion of the track frames 41 and 42, and the structure of the tension spring 72 or the elastic stopper body 74 can be simplified.

2 to 8, a front track frame 41 is connected to the traveling machine body 2 via a front arm 39, and a rear track frame 42 is connected to the traveling machine body 2 via a rear arm 40. The rear track frame 42 is connected to be extendable. Therefore, the front track frame 41 and the rear track frame 42 can be extended by the weight of the vehicle body, and the traveling crawler 49 can be supported with appropriate tension, and the traveling performance of the traveling crawler 49 can be easily improved. Further, even when the traveling machine body 2 tilts back and forth, the forward and backward tilting of the track frame 37 (the ground contact surface of the front traveling crawler 49) can be suppressed, and a good ride comfort for the operator who has boarded the control seat 8 can be maintained.

As shown in FIGS. 2 to 8, the upper surface side of the outer cylindrical body 65 as a spring box in which the tension spring 72 is accommodated is formed on an inclined surface. Therefore, accumulation of mud and the like on the upper surface side of the outer cylindrical body 65 can be reduced during field work, etc., and malfunction of the tension spring 72 caused by drying and solidification of adhering mud can be prevented, and maintenance workability can be improved. It can be improved.

As shown in FIGS. 1 to 8 and 11, a work vehicle including a traveling machine body 2 on which the engine 5 is mounted, a track frame 37 provided on the lower rear side of the traveling machine body 2, and a traveling crawler 49 attached to the track frame 37. The track frame 37 is divided into a front track frame 41 and a rear track frame 42, and the front track frame 41 and the rear track frame 42 are connected to be extendable. Therefore, the front track frame 41 and the rear track frame 42 can be extended to support the traveling crawler 49 in tension. For example, the traveling crawler 49 can be supported in tension by using the weight of the vehicle body, and the tension adjusting mechanism 44 for maintaining the tension of the traveling crawler 49 can be simplified in size.

As shown in FIGS. 2 to 8, the traveling machine body 2 includes a front arm 39 and a rear arm 40 for supporting the track frame 37, the front arm 39 is connected to a front track frame 41, and the rear arm is connected to a rear track frame 42. 40 are connected. Therefore, the traveling crawler 49 can be supported in a stable posture, and traveling performance in a field can be improved.

As shown in FIGS. 2 to 8, the front end side of the rear track frame 42 is slidably fitted on the rear end side of the front track frame 41, and a tension rod is provided between the front track frame 41 and the rear track frame 42. The slide cylinder 69 and the tension spring 72 are arranged. Therefore, the traveling crawler 49 can be tensioned by utilizing the weight of the vehicle body, and the tension adjusting mechanism 44 such as the tension spring 72 can be reduced in size and simplified. The tension spring 72 can also be used as a suspension, improving the ride comfort for the operator.

As shown in FIGS. 2 to 8, a rear arm 40 is rotatably disposed on the rear axle case 34 of the traveling machine body 2, and the front arm 39 and the rear arm 40 are disposed between the traveling machine body 2 and the track frame 37. It is arranged in a square shape when viewed from the side. Therefore, a spring body or the like that makes the front arm 39 elastic can be eliminated, the load of the tension spring 72 can be easily reduced, and the tension of the traveling crawler 49 can be properly maintained by utilizing the weight of the vehicle body.

As shown in FIGS. 1 to 8 and 11, a work vehicle including a traveling machine body 2 on which the engine 5 is mounted, a track frame 37 provided on the lower rear side of the traveling machine body 2, and a traveling crawler 49 attached to the track frame 37. , A pair of left and right front arms 39 and a pair of left and right rear arms 40 for supporting the pair of left and right track frames 37 on the traveling machine body 2 are provided, and the pair of left and right traveling crawlers 49 are independently suspended. Therefore, during the assembly work for mounting the pair of left and right traveling crawlers 49 on the traveling machine body 2, the unit body of the left and right track frames 37 is assembled in advance so that the traveling crawler 49 can be mounted, and then the front arm 39 and The unit bodies of the left and right track frames 37 can be connected via the rear arm 40. The assembly work of the traveling crawler 49 can be simplified.

As shown in FIGS. 2 to 8 and 11, the left and right rear axles 35 are disposed in the transmission case 17 via the left and right rear axle cases 34, and can rotate around the left and right rear axles 35. The left and right rear arms 40 are disposed on the left and right sides. Accordingly, the track frame 37 can be rotated around the rear axle 35 in response to a change in the contact pressure of the traveling crawler 49, and wet field running ability or a sudden stop function in farm work can be improved.

As shown in FIGS. 2 to 8, the connecting portion between the track frame 37 and the front arm 39 is arranged closer to the front portion of the traveling crawler 49 than the connecting portion between the traveling machine body 2 and the front arm 39. Therefore, the connecting portion (lower end pivot shaft 61) between the track frame 37 and the front arm 39 is moved forward by the vehicle body weight, with the connecting portion (upper pivot shaft 60) between the traveling machine body 2 and the front arm 39 as a fulcrum. The traveling crawler 49 can be tensioned by moving upward. The tension adjusting mechanism 44 of the traveling crawler 49 can be simplified and simplified.

As shown in FIGS. 2 to 8, the track frame 37 is divided into a front track frame 41 and a rear track frame 42, and the front track frame 41 is connected to the traveling machine body 2 via the front arm 39. The rear track frame 42 is connected via the rear arm 40, and the front track frame 41 and the rear track frame 42 are connected to be extendable. Therefore, the front track frame 41 and the rear track frame 42 can be extended by the weight of the vehicle body, and the traveling crawler 49 can be supported with appropriate tension, and the traveling performance of the traveling crawler 49 can be easily improved. Further, even when the traveling machine body 2 tilts back and forth, the forward and backward tilting of the track frame 37 (the ground contact surface of the traveling crawler 49) can be suppressed, and a good ride comfort for the operator who has boarded the control seat 8 can be maintained.

As shown in FIGS. 1 to 8 and 11, a work vehicle including a traveling machine body 2 on which the engine 5 is mounted, a track frame 37 provided on the lower rear side of the traveling machine body 2, and a traveling crawler 49 attached to the track frame 37. In the structure, an equalizer wheel 50 that supports the traveling crawler 49 is provided on the rear end side of the track frame 37, and the reverse angle of the traveling crawler 49 supported by the equalizer wheel 50 is the outer diameter locus of the traveling wheel. It is configured to approximate. Therefore, it is possible to easily ensure reverse running performance on a wet field or a rough road where the traveling crawler 49 is likely to sink, and it is possible to easily improve the direction changing workability at the time of pillow in the field.

As shown in FIGS. 2 to 8 and FIG. 11, the rear arm 35 has a structure including a rear axle 35 for driving the traveling crawler 49 and a drive sprocket (drive wheel body 36), and is supported on the axis of the rear axle 35. A rear end side of the track frame 37 is connected to the traveling machine body 2 via 40. Accordingly, the track frame 37 rotates around the rear axle 35 with respect to the front crawling or the rear rising subsidence of the traveling crawler 49 and the equalizer wheel 50 is displaced, so that the retreating angle of the traveling crawler 49 is set. It can be maintained properly.

As shown in FIGS. 2 to 8, the track frame 37 is formed by a front track frame 41 and a rear track frame 42 that can be expanded and contracted. Therefore, the tension of the traveling crawler 49 can be properly maintained by the forward and backward movement of the front track frame 41. For example, the traveling crawler 49 can be supported in tension by using the weight of the vehicle body, and the followability of the traveling crawler 49 with respect to the unevenness of the traveling road surface can be improved.

As shown in FIGS. 2 to 8, a front arm 39 and a rear arm 40 are arranged between the traveling body 2 and the front track frame 41 or the rear track frame 42 in a C shape in a side view. Therefore, a spring body that is elastically pressed against the front arm 39 can be eliminated, and the tension of the traveling crawler 49 can be maintained by utilizing the weight of the vehicle body.

Next, with reference to FIGS. 6, 9, and 10, a support structure for the wheels 50 arranged on the track frame 37 will be described. As shown in FIGS. 6, 9, and 10, a support cylinder 81 is fixed to the front and rear ends of the equalizer member 51 that is supported on the lower surface of the track frame 17 via a fulcrum shaft 52. A roller shaft 83 is rotatably supported on the support cylinder 81 via a pair of bearings 82. Both end sides of the roller shaft 83 are projected from the left and right openings of the support cylinder 81 toward the left and right outer sides. A pair of left and right rolling wheels 50 are fixed to both ends of the roller shaft 83 by fastening nuts 84. A rubber seal 85 is provided outside the bearing bearing 82 in the left and right openings of the roller support cylinder 111. The bearing bearing 82 is formed of a ball bearing in which a large amount of lubricant is held inside, so that it is not necessary to fill the lubricating grease.

As shown in FIG. 10, the rubber seal 85 and the seal presser 86 are fitted on the outer peripheral side of the boss portion 50a of the roller wheel 50 on the outer peripheral side of the boss portion 50a to be inserted into the left and right openings of the support cylinder 81. Of the outer peripheral side of the roller shaft 83, an O-ring 87 is fitted into the abutting portion between the side surface of the bearing bearing 82 and the end of the boss portion 50a. An O-ring 88 is fitted into the butt portion. The retaining ring 89 is locked to the opening end of the support cylinder 81, and the seal pressing body 86 is supported inside the opening of the support cylinder 81. The support cylinder 81 is formed by cutting a hard stainless steel alloy pipe. The seal pressing body 86 is formed by molding a material softer than the support cylinder 81 (aluminum alloy, plastic, or cast iron). Formed by casting. The seal pressing body 86 as a bearing retaining body is formed of a soft material compared to the cast iron roller 50.

As shown in FIG. 10, a labyrinth ring groove 50b is formed on the outer peripheral surface of the boss portion 50a of the roller wheel 50 on the outer peripheral surface of the boss portion 50a facing the inner hole surface of the seal presser 86, and the labyrinth ring groove 50b is formed. A plurality of thin labyrinth rings 90 made of spring steel are fitted, and the outer peripheral surface side of the labyrinth ring 90 is slidably brought into contact with the inner hole surface of the seal presser 86. A support cylinder 81 as a bearing cylinder of the track frame 37 is provided. A support shaft (roller shaft 83) is rotatably supported by a bearing bearing 82, and the wheel 50 is fastened and fixed to the end of the roller shaft 83, and on the inner peripheral side of the support cylinder 81. A seal presser body 86 which is a bearing retaining body is inserted, and the labyrinth ring 90 is slidably brought into contact with the shaft hole surface of the seal presser body 86. The labyrinth ring 90 is attached with the smallest radial / axial gap in the labyrinth ring groove 50b, and the labyrinth ring 90 suppresses intrusion of muddy water and prevents the rubber seal 85 from being damaged.

As shown in FIGS. 1, 6, 9, and 10, the traveling machine body 2 on which the engine 5 is mounted, the track frame 37 provided on the lower rear side of the traveling machine body 2, and the track frame 37 are mounted via the wheels 50. In the work vehicle including the traveling crawler 49, the labyrinth ring groove 50b is formed on the outer periphery of the boss portion 50a of the wheel 50, and the labyrinth ring 90 is fitted into the labyrinth ring groove 50b. Therefore, it is not necessary to insert grease into the bearing portion 82 of the roller 50, and it is possible to eliminate problems such as leakage of the grease and simplify maintenance work such as replenishment of the grease. Can be

As shown in FIGS. 6, 9, and 10, a roller shaft 83 as a support shaft is rotatably supported on a bearing cylinder (supporting cylinder 81) of the track frame 37 via a bearing bearing 82. The roller 50 is fastened and fixed to the end of the body 83, and a seal presser body 86 as a bearing retaining body is inserted into the inner peripheral side of the support cylinder 81 (bearing cylinder), and the seal presser body 86 is inserted. The labyrinth ring 90 is slidably brought into contact with the shaft hole surface. Accordingly, the waterproof / mudproof function of the labyrinth ring 90 can be easily improved while the structure of the bearing 82 can be simplified.

6, 9, and 10, the rolling wheel 50 is formed by casting, and the seal pressing body 86 is formed of a softer material than the rolling wheel 50. Therefore, the seal presser body 86 can be formed of aluminum die cast or synthetic resin, and the rust prevention of the seal presser body 86 can be made unnecessary.

Next, a second embodiment of the present invention will be described with reference to FIGS. Here, in the second and subsequent embodiments, the same configuration and operation as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed description thereof is omitted. Below, a difference with 1st Embodiment among 2nd Embodiment is demonstrated.

In the second embodiment, a front equalizer member 51 on which two front rolling wheels 50 are pivotally supported is provided, and the front equalizer member 51 is pivotally supported on the front track frame 41. Further, a rear equalizer member 51 on which two rear wheels 50 are pivotally supported is provided, and the rear equalizer member 51 is pivotally supported on the rear track frame 42. Two front rollers 50 are rotatably provided on the front track frame 41, and two rear wheels 50 are rotatably provided on the rear track frame 42. Of the inner peripheral surface of the traveling crawler 49, the front wheel 50 and the rear wheel are arranged on the inner peripheral surface between the front driven wheel body 46 and the rear driven wheel body 47 (the inner peripheral surface on the ground contact side of the traveling crawler 49). The ring 50 is brought into contact. The front rolling wheel 50 and the rear rolling wheel 50 are configured to land and support the grounding side of the traveling crawler 49.

As shown in FIGS. 14 to 19 and 22, the front equalizer member 51 is supported on the lower end portion of the spring receiving bracket body 71 via the fulcrum shaft 52, and the fulcrum receiving bracket 53 is mounted on the rear end portion of the rear track frame 42. The rear equalizer member 51 is supported by the fulcrum receiving bracket 53 via the fulcrum shaft 54. The upper end side of the rear arm 40 is pivotally supported by the rear axle case 34, and the lower end side of the rear arm 40 is detachably fastened and fixed to the fulcrum receiving bracket 53 by a bolt 55. That is, the rear arm 40 is erected in a substantially vertical posture through the fulcrum receiving bracket 53 at the rear end portion of the rear track frame 42. The left and right rear arms 40 are disposed so as to be rotatable around the left and right rear axles 35, and the rear end side of the track frame 37 is connected to the traveling machine body 2 via the rear arms 40 that are pivotally supported on the axis of the rear axle 35. The retraction angle (rear facing angle) of the traveling crawler 49 supported by the equalizer rear wheel 50 disposed on the rear end side of the track frame 37 is the outer diameter locus of a general traveling wheel that is pivotally supported by the rear axle 35. It is constituted so as to approximate to the tangent angle.

On the other hand, the upper end side of the front arm 39 is pivotally supported on the arm support member 38 on the outer side surface of the body frame 23 via the upper end pivot shaft 60, and the lower end is pivotally mounted on the inner side surface of the front track frame 41. A lower end side of the front arm 39 is pivotally supported via a shaft 61 so that the front arm 39 is supported in a rearward inclined posture between the vehicle body frame 23 and the front track frame 41. The connecting portion (lower end pivot shaft 61) between the track frame 37 and the front arm 39 is disposed closer to the front portion of the traveling crawler 49 than the connecting portion (upper end pivot shaft 60) between the traveling machine body 2 and the front arm 39. When a lower end pivot shaft 61 is disposed in front of the upper end pivot shaft 60 and the ground pressure (tension force) of the traveling crawler 49 changes, the front arm 39 rotates around the upper pivot shaft 60, and the front arm 39, the lower end side of the rear arm 40 is moved directly below the rear axle 35 as the circumferential length of the traveling crawler 49 becomes longer with time. It is configured to shift from the initial state of the suspended substantially vertical posture to the forward inclined posture displaced to the rear side of the rear axle 35. That is, when the front and rear lengths of the front track frame 41 and the rear track frame 42 are increased, the front arm 39 and the rear arm 40 have a C-shaped side view with respect to the traveling machine body 2 (the distance between the upper ends of the

arms

39 and 40 is increased). The shape is small and the distance between the lower ends increases.

As shown in FIGS. 14, 15, and 22, a work vehicle including a traveling machine body 2 on which the diesel engine 5 is mounted, a track frame 37 provided on the lower side of the traveling machine body 2, and a traveling crawler 49 that is attached to the track frame 37. The track frame 37 is divided into a front track frame 41 and a rear track frame 42, the front end side of the rear track frame 42 is slidably connected to the rear end side of the front track frame 41, and the front end of the front track frame 41 is The front driven wheel body 46 and the front wheel 50 are arranged on the side, and the rear driven wheel body 47 and the rear wheel 50 are arranged on the rear end side of the rear track frame 42. Therefore, the traveling crawler 49 can be supported to an appropriate tension force by moving the front driven wheel body 46 back and forth without changing the ground contact angle of the front portion of the traveling crawler 49, and the traveling performance of the traveling crawler 49 can be easily improved. However, it is possible to suppress the forward and backward tilting of the track frame 37 (the ground contact surface of the traveling crawler 49), and to maintain a good ride comfort for the operator who has boarded the control seat 8.

As shown in FIGS. 14, 15, and 22, the rear track frame 42, the rear driven wheel body 47, and the rear wheel 50 are rotatably supported around the rear axle 35 of the traveling machine body 2. . Therefore, while the forward / backward tilt of the track frame 37 (the ground contact surface of the traveling crawler 49) can be suppressed, the front / rear grounding width of the traveling crawler 49 can be changed based on the rear portion of the traveling crawler 49, and the traveling crawler can be changed. It is possible to easily suppress fluctuations in the ground contact pressure of 49.

As shown in FIGS. 14, 15, and 22, the front track frame 41 is connected to the traveling machine body 2 via the front arm 39, and the front arm 39 is rotated to move the front track frame 41 and the front driven wheel body 46. The front wheel 50 is configured to move in the front-rear direction. Therefore, the forward and backward tilting of the track frame 37 (the ground contact surface of the traveling crawler 49) can be suppressed, and the tension of the traveling crawler 49 can be properly maintained using the weight of the vehicle body such as the traveling machine body 2.

14, 15, and 22, the rear track frame 42 is connected to the traveling machine body 2 via the rear arm 40, and the rear arm 40 is connected to the rear track frame 42 via the fulcrum receiving bracket 53. The rear wheel 50 is attached to the fulcrum support bracket 53, while the front track frame 41 is provided with a spring support bracket body 71, and the front track frame 41 and the rear track frame 42 are interposed between the front track frame 41 and the rear track frame 42 via the spring support bracket body 71. The tension spring 72 of the tension adjusting mechanism 44 is arranged, and the front rolling wheel 50 is attached to the spring receiving bracket body 71. Accordingly, the rear rolling wheel 50 can be supported by the fulcrum receiving bracket 53 and the support structure of the track frame 37 can be simplified, and the front rolling wheel 50 can be supported by the spring receiving bracket body 71 and traveled. The tension structure of the crawler 49 can be simplified.

2 traveling machine body 5 diesel engine 37 track frame 39 front arm 40 rear arm 41 front track frame 42 rear track frame 49 traveling crawler 50 wheel 50a wheel boss 50b labyrinth ring groove 53 fulcrum receiving bracket 71 spring receiving bracket body 72 tension spring 81 Support cylinder (bearing cylinder)
82 Bearing bearing 83 Roller shaft (support shaft)
86 Seal retainer (bearing retaining member)
90 Labyrinth Ring

Claims

In a work vehicle comprising a traveling machine body on which an engine is mounted, a track frame provided on a lower rear side of the traveling machine body, and a traveling crawler attached to the track frame,
The structure is provided with an equalizer wheel that supports the traveling crawler on the rear end side of the track frame, so that the reverse angle of the traveling crawler supported by the equalizer wheel approximates the outer diameter locus of the traveling wheel. A work vehicle characterized by comprising.
A structure including an axle and a drive sprocket for driving the traveling crawler, wherein a rear end side of a track frame is connected to the traveling machine body via an arm pivotally supported on an axis of the axle. Item 4. The work vehicle according to Item 1.
2. The work vehicle according to claim 1, wherein the track frame is formed by a front track frame and a rear track frame that are extendable and contractible.
4. The work vehicle according to claim 3, wherein a front arm and a rear arm are arranged in a C shape in a side view between the traveling machine body and the front track frame or the rear track frame.
2. The work vehicle according to claim 1, wherein a labyrinth ring groove is formed on an outer periphery of a boss portion of the equalizer wheel, and a labyrinth ring is fitted into the labyrinth ring groove.
A support shaft is rotatably supported on a bearing cylinder of the track frame via a bearing bearing, and a wheel is fastened and fixed to an end of the support shaft, and a bearing is provided on the inner peripheral side of the bearing cylinder. 6. The work vehicle according to claim 5, wherein the retaining body is inserted, and the labyrinth ring is brought into sliding contact with the shaft hole surface of the bearing retaining body.
6. The work vehicle according to claim 5, wherein the equalizer wheel is formed by casting, and the bearing retaining member is formed of a softer material than the wheel.
In a work vehicle comprising a traveling machine body on which an engine is mounted, a track frame provided below the traveling machine body, and a traveling crawler attached to the track frame,
The track frame is divided into a front track frame and a rear track frame, a front end side of the rear track frame is slidably connected to a rear end side of the front track frame, and a front driven wheel is formed on the front end side of the front track frame. A work vehicle comprising a front wheel and a rear driven wheel and a rear wheel disposed on a rear end side of the rear track frame.
The work vehicle according to claim 8, wherein the work vehicle is configured to rotatably support a rear track frame, a rear driven wheel body, and a rear wheel around an axle of the traveling machine body.
The front track frame is connected to the traveling machine body via a front arm, and the front arm is rotated so that the front track frame, the front driven wheel body, and the front wheel are moved in the front-rear direction. The work vehicle according to claim 8, characterized in that:
The rear track frame is connected to the traveling machine body via a rear arm, the rear arm is connected to the rear track frame via a fulcrum receiving bracket, and the rear wheel is attached to the fulcrum receiving bracket, while the front track frame is connected. Provided with a spring receiving bracket body, a tension spring of the tension adjusting mechanism for the traveling crawler is disposed between the front track frame and the rear track frame via the spring receiving bracket body, and a front wheel is mounted on the spring receiving bracket body. The work vehicle according to claim 8, wherein the work vehicle is attached.