JPS5843501Y2 - Hydraulic lift device for agricultural tractors - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a hydraulic lift device for an agricultural tractor, and particularly to an installation structure for a hydraulic lift device in a tractor in which the body center and the left and right tread centers are eccentric.

When a hydraulic lift device is mounted on an agricultural tractor, it is desirable to install it at the tread center in order to equalize the left and right weight distribution.

In a structure in which the fuselage center and the tread center coincide with each other, since the tread center has a rear case, the hydraulic lift device can be placed on the rear case.

Therefore, the transmission case constituting the rear case can be used as an oil reservoir, and the hydraulic oil of the hydraulic lift can be directly returned to this oil reservoir.

That is, no particular difficulty arises in the hydraulic piping to the hydraulic lift device, especially the piping for returning hydraulic oil.

However, in a structure where the fuselage center and tread center are eccentric to each other, if a hydraulic lift device is to be installed at the tread center, the hydraulic lift device must be installed in a location separate from the rear case located at the fuselage center. Must be.

Therefore, there is a risk that the structure will become complicated, such as requiring separate piping for returning hydraulic oil from the hydraulic lift device to the rear case.

In view of the above points, it is an object of the present invention to provide an installation structure that can be easily configured, such as eliminating the need for special hydraulic piping.

The structure of the present invention will be explained based on the drawings showing one embodiment. Fig. 1 shows the whole of the tractor of the present invention, in which an engine 1 is mounted at the front of the body, and a clutch housing 2 is mounted at the rear of the engine 1. However, a transmission case 3 as a rear case is integrally connected to the rear of the engine 1, and the power from the engine 1 is transmitted to the transmission mechanism inside the transmission case 3 via the clutch and main shaft installed in the clutch housing 2. The transmission mechanism drives the rear wheels 4 through the differential gear.

In the figure, 5 is a front wheel, 6 is a steering wheel, and 7 is a seat.

However, as shown in FIG. 2, the center of the machine body indicated by 8 does not coincide with the center 9 between the left and right treads, but is eccentric to the left in the direction of travel of the tractor. The rear hydraulic lift device 10 for raising and lowering the working machine is disposed on the tread center 9 on the underside of the seat 7, and its installation structure is as shown in FIG. 3, and the structure will be explained below.

First, to explain the structure on the eccentric side, numeral 39 is a brake cam plate attached to the outside in the eccentric direction of the transmission case 3 as a rear case, numeral 11 is a rear axle case directly connected to the outside of the brake cam plate 39, and numeral 12 is the transmission case. The intermediate axle 13 is supported between the differential carrier 12 and the rear axle case 11.

Although not shown, a differential side gear is attached to the inner end of the intermediate axle 13 and receives power from the engine 1, and a final pinion 14 is attached to the outer end of the differential side gear.

A final gear 15 meshes with the final pinion 14, and is attached to the rear axle 16 supported at the bottom of the rear axle case 11 to perform final deceleration, and also rotates the hub 17, disc 18, and rim 19 from the rear axle 16. Driving force is transmitted to the tires 20 via the tire 20.

In addition, in the figure, 21 is a brake cam lever, 22 is a camshaft,
23 is a brake drum.

Now, in contrast to the structure of the eccentric side, that is, the body center side, as described above, the non-eccentric side, that is, the tread center side, is configured as follows.

That is, on the eccentric side, the mission case 3
The brake cam plate 39 was directly connected to the outside of the transmission case 3, but on the opposite side, the brake cam plate 39 was not directly connected, and a slightly larger diameter A rear axle housing 24 is directly connected to the rear axle housing 24.

Therefore, the intermediate axle 13 is formed to be elongated accordingly.

In the upper part of this rear axle housing 24,
A flange 25 is provided protruding from the tread center 9, and a hydraulic case 27 is mounted on the flange 25 by bolts 26.
The hydraulic lift device 10 is installed with the flange portion 28 of the hydraulic lift device 10 fixed.

Reference numeral 30 denotes a partition wall that is integrally connected between the flange 25 protruding from the rear axle housing 24 and the outer wall of the transmission case 3.

29 is the rear axle housing 2 at this partition wall 30.
This is a return oil passage that is defined inside the transmission case 4 and directly communicates the hydraulic case 27 and the transmission case 3, and is used to return the hydraulic oil of the hydraulic lift device 10 into the transmission case 3.

31 is a lifting shaft 32 which is a lift arm.

Reference numeral 33 in FIGS. 1 and 2 is an operating lever case attached to an L-shaped support rod 34 that supports the handle 6, and the shaft portion of the operating lever 35 supported by the case 33 and the hydraulic lift device 10 operating shafts 36 are connected by a connecting rod 37, whereby the operation of the hydraulic lift device 10 can be controlled remotely.

38 indicates a feedback device.

Furthermore, on this side as well, a differential side gear is attached to the inner end of the intermediate axle 13 to transmit power.
This is the same as the eccentric direction side.

Further, in the present invention, the brake cam plate 39 is not interposed between the rear axle housing 24 and the rear axle case 11, and the rear axle housing 24 can be directly connected to the rear axle case 11.

The present invention has the above-described configuration, and a return oil passage defined by a partition wall in the rear axle housing is formed in the rear axle housing, so that the hydraulic lift device mounted on the rear axle housing and the rear case can be connected to each other. Direct communication becomes possible.

Therefore, there is no need for special piping for returning the hydraulic oil of the hydraulic lift device into the rear case, resulting in a simple structure.

Furthermore, since the partition wall itself serves as a reinforcement, there is no need to use a special member as a reinforcing member even when a heavy hydraulic lift is mounted, and a clean appearance can be obtained.

[Brief explanation of drawings]

FIG. 1 is a side view of the tractor of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a longitudinal sectional view of the rear axle portion. 3... Mission case, 8... Airframe center 9... Tread center, 10...
... Hydraulic lift device, 11 ... Rear axle case, 24 ... Rear axle housing, 2
9... Return oil path, 30... Bulkhead.

Claims (1)

[Scope of utility model registration request] In a tractor in which the body center is eccentric with respect to the center between the left and right treads, a rear axle housing is connected between the rear axle case and the outer wall of the rear case located at the body center on the opposite side to the eccentric direction, and the rear axle housing is connected to the rear axle housing. A hydraulic lift device is mounted on the rear axle housing, and a return oil passage defined by a partition wall in the rear axle housing is formed in the rear axle housing in order to return the hydraulic oil of the hydraulic lift device to the rear case side. Features: Hydraulic lift device for agricultural tractors.