JPH0616159A - Crawler travel device for working vehicle - Google Patents

Abstract

PURPOSE:To properly modify the frontward and backward inclination of a body by forming hydraulic cylinders for a right and left crawler travel device into a double acting type and connecting the hydraulic cylinders in series to a control valve to allow the feed and discharge of the same quantity of pressure oil to/from the right and left hydraulic cylinders in a synchronous manner. CONSTITUTION:When the first hydraulic cylinder 23 is expanded, an operating arm 22 on the back side is oscillated, an operating arm 21 on the front side is simultaneously oscillated via a linked rod 25, and oscillating links 15, 16 integrated with the operating arms 21, 22 are also oscillated to elevate up and down a truck frame 17 in parallel. When the first hydraulic cylinder 23 is fixed and the second cylinder 24 is expanded, the oscillating link 15 on the front side is only oscillated up and down to modify the frontward and backward inclination of a body. The second hydraulic cylinder 24 formed into a down acting type is connected in series to a control valve 26 so that oil discharged from one hand of the second hydraulic cylinder 24 can be served as oil fed to the other hand of the second hydraulic cylinder 24. In this way, the right and left hands of the second hydraulic cylinder 24 are elongated in the same quantity to perform accurate, proper frontward and backward inclination modification.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crawler traveling device mounted on a working vehicle such as a combine or earthmoving machine.

[0002]

2. Description of the Related Art As a combine crawler traveling device, for example, as disclosed in Japanese Patent Application Laid-Open No. 3-79421, a drive sprocket is fixedly mounted on the vehicle body frame side, and a ground roller and an adjustable fixed tension wheel are provided. The track frame provided is supported by the body frame via a pair of front and rear swing links so as to be capable of relative vertical movement, and the track frame moves to the drive sprocket side as the swing link descends and swings with respect to the body frame. The postures of both swing links are set so that the swing arms are swingable integrally with each of the swing links, and both swing arms are pivotally connected by a linking rod to operate on the side far from the drive sprocket. The arm is configured to swing by a hydraulic cylinder, and the free end of one swing link and the track frame are connected via an auxiliary link. As well as supporting connection, which the linkage rod and telescopic drivable configuration the second hydraulic cylinder are known. The crawler traveling device configured as described above can move the body frame in parallel with the track frame by operating the first hydraulic cylinder,
If the left and right crawler traveling devices are moved up and down by the same amount, the vehicle body can be moved up and down in parallel, and if the left and right crawler traveling devices are moved up and down, the vehicle body can be tilted left and right. It is possible to elevate or lower the vehicle body frame according to the vehicle body subsidence in the field, or to correct the lateral inclination of the vehicle body. Further, by operating the second hydraulic cylinder, the vehicle body frame can be tilted forward or downward with respect to the track frame to correct the longitudinal tilt of the vehicle body.

[0003]

In the above structure, the first hydraulic cylinder needs to be able to operate independently in the left and right crawler traveling devices in order to cope with the left and right inclination of the vehicle body, but the second hydraulic cylinder has the left and right sides. The crawler traveling device does not operate independently, but always operates in the same direction at the same time. In this case, as a means of simultaneously operating the second hydraulic cylinders on the left and right in the same direction, it is conceivable that a flow dividing valve is used.
If pressure oil is not supplied to the hydraulic cylinders, an error occurs in the front and rear tilt postures of the left and right crawler traveling devices, and the hydraulic device for driving the second hydraulic cylinder becomes expensive. It is an object of the present invention to accurately operate the second hydraulic cylinders on the left and right for correcting the front-rear tilting posture of the vehicle body with an inexpensive hydraulic device.

[0004]

In order to achieve the above object, the present invention is a crawler traveling device for a working vehicle as described above, wherein each of the second hydraulic cylinders of the left and right crawler traveling devices is of a return type. The control valve is connected in series.

[0005]

According to the above construction, for example, when pressure oil is supplied to the bottom side oil chamber of one of the second hydraulic cylinders and the second hydraulic cylinder extends, the piston rod side oil of the second hydraulic cylinder is generated. The oil discharged from the chamber is sent to the bottom side oil chamber of the other second hydraulic cylinder, and the other second hydraulic cylinder also extends by the same amount.

[0006]

Therefore, with a low-priced hydraulic system that does not use a high-precision and expensive shunt valve, the same amount of pressure oil is constantly supplied to and discharged from the left and right second hydraulic cylinders to ensure reliable synchronization, and the front and rear of the vehicle body It became possible to correct the inclination accurately.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 4, the crawler traveling device 1 is provided to the left and right.
The harvesting section 2 is connected to the front part of the traveling vehicle equipped with so as to be able to move up and down, and the threshing device 3 is mounted on the traveling vehicle to form a self-removing combine. As shown in FIG. 5, the raising device 4 provided at the front end of the mowing unit 2 is configured to be swingable left and right around the upper drive shaft 5, and
The connecting boss 4a provided at the lower part of the raising device 4 is slidably connected to the arc-shaped support rod 8 attached to the support rod 7 of the weeding tool 6, and starts raising according to the state of lodging of the crop. The position can be adjusted left and right.
As shown in FIGS. 1 and 2, the axle frame 11a of the mission case 11 is connected to the front side of the vehicle body frame 10, and the drive sprockets 12 are provided at both ends of the axle frame 11a. And the body frame 1
A pair of support shafts 13 and 14 are rotatably supported before and after 0, and swing links 15 and 16 are fixed to the outer ends of the support shafts 13 and 14 rearward of the machine body. The track frame 17 of the crawler traveling device 1 is equipped with a plurality of ground rollers 18 in parallel, and the track frame 1
7 Adjustable and fixed tension wheel 19 is equipped at the rear end, and
The rear end of the swing link 15 on the front side is directly pivotally connected to the track frame 17, and the swing of the rear side is performed by an auxiliary link 20 attached to the rear portion of the track frame 17 so as to swing back and forth around the horizontal axis P. The rear end of the link 16 is pivotally connected. The operating arms 21 and 22 are fixed to the inner ends of the support shafts 13 and 14, respectively, and the first hydraulic cylinder 23 extends between the operating arm 22 on the rear side and the lateral frame 10a on the vehicle body frame 10 side. It is installed. Further, a double-acting type second arm is provided across both the operating arms 21 and 22.
A linking rod 25 including a hydraulic cylinder 24 is installed. With the above structure, as shown in FIG.
When the first hydraulic cylinder 23 is expanded / contracted and the rear working arm 22 is oscillated while the hydraulic cylinder 24 is fixed at the intermediate position, the linkage rod 25 also oscillates the front operating arm 21. These operating arms 21,
The swing links 15 and 16 integrated with 22 swing up and down. As a result, the entire track frame 17 can be moved up and down in parallel, and by performing this operation on the left and right crawler traveling devices 1, the vehicle body can be moved up and down in parallel and the lateral inclination can be corrected. Then, when the second hydraulic cylinder 24 is driven to expand and contract while the first hydraulic cylinder 23 is fixed at a predetermined position, FIG. 3B and FIG.
As shown in (4), the front swing link 15 is vertically driven to swing while the rear swing link 16 is fixed. As a result, the track frame 17 is swingably driven up and down about the rear side, and the front-back inclination of the vehicle body can be corrected. In order to tilt the vehicle body in the front-rear direction as described above, it is necessary to prevent the left and right crawler traveling devices 1 from being displaced. Therefore, as shown in FIG. It is configured to be connected in series to receive pressure oil supply from the control valve 26. According to this configuration, for example, pressure oil is supplied to the bottom-side oil chamber of one of the second hydraulic cylinders 24 (a) to supply the second hydraulic cylinder 24 (a).
When (a) is extended, the second hydraulic cylinder 24
The oil discharged from the piston rod side oil chamber in (a) is the second
It is supplied to the bottom side oil chamber of the hydraulic cylinder 24 (b), and the second hydraulic cylinder 24 (b) is also supplied to the second hydraulic cylinder 24 (b).
The extension operation is performed by the same amount as in (a). When the track frame 17 is lowered by the first hydraulic cylinder 23 and the second hydraulic cylinder 24 in this way, the track frame 17 approaches the drive sprocket 12, and therefore the winding length of the crawler belt 27 does not change. Few. Accordingly, a mechanism for automatically adjusting the tension of the crawler belt 27 is not particularly required, and the tension wheel 19 can be an adjustable fixed type.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a side view of a crawler traveling device.

FIG. 2 is a plan view of a crawler traveling device.

FIG. 3 (a) is an operation explanatory view showing a parallel ascending / descending operation of the vehicle body;

FIG. 4 is an overall side view of the combine.

FIG. 5 is a front view of the raising device.

[Explanation of symbols]

 10 Body Frame 12 Drive Sprocket 15 Swing Link 16 Swing Link 17 Track Frame 18 Grounding Wheel 19 Tension Wheel 20 Auxiliary Link 21 Working Arm 22 Working Arm 23 First Hydraulic Cylinder 24 Second Hydraulic Cylinder 25 Coupling Rod 26 Control Valve

Claims (1)

[Claims] 1. A pair of front and rear track frames (17) each having a drive sprocket (12) fixedly mounted on the body frame (10) side and provided with a grounding wheel (18) and an adjustable fixed tension wheel (19). Swing links (15), (16)
The track frame (17) is supported by the vehicle body frame (10) so as to be movable up and down relative to the track frame (17) as the swing links (15) and (16) move downward with respect to the vehicle body frame (10). The postures of both swing links (15) and (16) are set so as to shift to the drive sprocket (12) side, and an operating arm (21) swings integrally with the swing links (15) and (16). ), (22) are provided, both operating arms (21), (22) are pivotally connected by a linking rod (25), and one operating arm (22) is oscillated by the first hydraulic cylinder (23). Configured to
The free end of the one swing link (16) and the track frame (17) are pivotally connected to each other via an auxiliary link (20), and the linking rod (25) is driven to extend and contract by a second hydraulic cylinder (24). In the crawler traveling device of the work vehicle that is configured to be possible, each second hydraulic cylinder (24) of the left and right crawler traveling devices is configured to be a return type and is connected in series to the control valve (26). A crawler traveling device for work vehicles.