JPH0784139B2 - Power transmission structure of tractor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a power transmission mechanism from an engine to a working machine, particularly in a small tractor among tractors.

(B) Conventional Technology Conventionally, in a tractor, a technology of configuring a traveling drive transmission using an HST type transmission has been known.

For example, Japanese Utility Model Laid-Open No. 60-135226, Japanese Patent Laid-Open No. 60-1028, Japanese Utility Model Laid-Open No. 54-32433 and Japanese Utility Model Laid-Open No. 55-41984 can be used.

However, the traveling drive transmission using the conventional HST type transmission has a complicated structure and is expensive.

(C) Problems to be Solved by the Invention An object of the present invention is to provide a mass-production type traveling drive transmission that can be attached to a small tractor and is inexpensive.

For a small tractor, it is necessary to make the overall configuration simple and low in cost, and it is desirable to have a general-purpose power transmission structure that can be mounted on a tractor with multiple specifications and that can be mounted in various forms depending on the mounting method. -ing

As a result, the traveling drive transmission can be mass-produced and the price can be reduced.

Further, the present invention provides a power transmission structure for various tractors, in which the mounting position can be easily changed, the wheel base can be easily changed, and the vertical position of the PTO shaft 9 can be easily adjusted.

(D) Means for Solving the Problems The object of the present invention is as described above, and a configuration for achieving the object will be described below.

An HST type transmission H having a hydraulic pump 11 having a vertical axis and a hydraulic motor 12 arranged side by side is mounted on the upper part of the traveling drive transmission M in which the drive axles 7, 7 are projected to the left and right. The motor shaft projecting downward is inserted into the traveling drive transmission M to transmit power, and the pump shaft 5 projecting up and down of the hydraulic pump 11 allows the working machine driving hydraulic pump 6 to be attached to the lower projecting portion. An input transmission A is attached to the upward projecting portion, and power is transmitted from the engine E to the input shaft 4 projecting forward from the input transmission A through the universal joint shaft 2 and above the input shaft 4. The bevel gear and the bevel gear at the upper end of the pump shaft 5 are meshed with each other, and the input shaft 4 is configured to transmit power to the working machine drive device B from a portion protruding rearward from the input transmission device A.

(E) Embodiments The object and structure of the present invention are as described above. Next, the detailed structure of the present invention will be described based on the structure of the embodiment shown in the accompanying drawings.

FIG. 1 is an overall side view of a tractor of the present invention, FIG. 2 is a side view of a power transmission structure which is an essential part of the present invention, FIG. Is also a rear view, FIG. 5 is a side view showing another structure for mounting the traveling drive transmission M on the tractor, and FIG. 6 is also a traveling drive transmission M.
FIG. 7 is a side view showing another configuration in a state where the arrangement of the HST type transmission H and the transmission is changed.

FIG. 1 will be described.

Engine E is located inside the hood at the front of the tractor. Airframe frames 3L and 3R fixed to the left and right side surfaces of the engine E extend from the front end to the rear end of the airframe.

The power transmission structure of the present invention is arranged and fixed between the machine body frames 3L and 3R.

In the power transmission structure, the power from the engine E is input, and the input transmission device A for branching in two directions and one power after being divided by the input transmission device A are used for the drive axle 7
HST transmission H and traveling drive transmission M transmitted to
It is composed of a working machine drive device B that transmits the other branched power to the PTO shaft 9.

The tip of the pump shaft 5 of the HST transmission H is projected downward, and a hydraulic pump 6 for driving the working machine can be attached to the tip of the pump shaft 5. The pressure discharged from the hydraulic pump 6 for driving the working machine is attached. The oil drives the hydraulic motor 23 for driving the working machine of the rotary mower device R.

The power from the engine E is transmitted to the input transmission A by the universal joint shaft 2 and is branched in two directions in the input transmission A, one of which is input to the pump shaft 5 of the HST transmission H, and The other is through the universal joint shaft 13 and the input shaft 33 of the working machine drive device B.
Power is transmitted to.

A rotary mower device R is hung on the abdomen between the front and rear wheels of the tractor, and the rotary mower device R is driven by a hydraulic motor 23 for driving the working machine.

Next, referring to FIG.

In this configuration, it is necessary to provide the PTO shaft 9 for driving the working machine mounted on the rear part of the tractor, and also to drive the rotary mower device R suspended on the abdomen of the tractor, and to obtain traveling power. In order to transmit power to the three directions, the input power transmission device A is arranged to divide the power into two.

The power of the universal joint shaft 2 is transmitted to the input shaft 4 in the input transmission device A. A bevel gear 10 is fixedly installed at an intermediate portion of the input shaft 4, and the bevel gear 10 meshes with a bevel gear 14 at an upper end of the pump shaft 5 to transmit power.

The HST type transmission device H is composed of a hydraulic pump 11 having a vertical shaft and a hydraulic motor 12, and is an HST type transmission device H in which the hydraulic pump 11 and the hydraulic motor 12 are integrated. The HST transmission H is mounted and fixed on the upper surface of the traveling drive transmission M.

The pump shaft 5 of the hydraulic pump 11 does not have to be inserted into the traveling drive transmission M, but can project and have the working machine driving hydraulic pump 6 attached to the lower end thereof.

In addition, the hydraulic motor is driven by the pressure oil discharged from the hydraulic pump 11.
12 is driven, and the shaft of the hydraulic motor 12 is inserted into the traveling drive transmission M.

The traveling drive transmission M is constructed by combining the upper and lower cases 8a and 8b, and the drive axle 7 is bearing-supported on the mating surface.

The power is branched into two directions in the input transmission A, and the pump shaft 5 is branched into two directions of traveling and rotary mower R.

The cooling fan 1 is fixedly installed on the pump shaft 5 between the input transmission A and the HST transmission H, and the HST is cooled by the cooling fan 1.
The variable speed transmission H is being cooled.

On the other hand, the rear end of the input shaft 4 is projected as it is, the universal joint shaft 13 is fixed to the rear end of the input shaft 4, and the input shaft 33 of the working machine drive device B is connected to the rear end of the shaft 13. .

Next, referring to FIG.

The dry clutch device C is arranged between the input shaft 33 and the shaft 10 on the same axis. This part is not configured as an oil bath, but is open to the air.

The dry clutch device C connects and disconnects the power of the PTO shaft 9. By rotating the clutch lever 21 back and forth, the lever 21a moves the release bearing 22 back and forth,
The dry clutch device C is turned on and off. Instead of the dry clutch device C, the electromagnetic clutch device may be replaced because the portion is dry. The electromagnetic clutch is cheaper and requires less operating force.

A gear 16 on the shaft 10 meshes with a gear 17 on the counter shaft 15, and the gear 17 meshes with a gear 18 on the PTO shaft 9.

The PTO shaft 9 is configured as a cylinder shaft, and the spline shaft on the working machine side is fitted and inserted in the PTO shaft 9.

The lock ball 20 and the lock operation plate 19 lock the shaft on the working machine side inserted into the PTO shaft 9.

The lock ball 20 is fitted into the recess of the shaft to be inserted,
The inserted shaft is prevented from coming off.

Next, FIG. 6 will be described.

In this configuration, the same traveling drive transmission M is used, but the HST type transmission H mounted on the traveling drive transmission M is of the horizontal axis type, and The pump shaft of the pump 11 is also used as the input shaft 4.

The universal joint shaft 13 is connected to the rear portion of the input shaft 4, and the input shaft 33 is further connected to the rear end thereof.

In this structure, the cooling fan 1 attached to the pump shaft is attached on the input shaft 4 and blows air backward.

Next, the configuration of FIG. 5 will be described.

The tractor with this configuration is a PTO for work equipment mounted on the rear.
The shaft 9 is not prepared, and the engine E is constructed vertically.

The pulley 2 is attached to the downward protruding portion of the engine E.
The pump shaft 5 of the HST transmission H is provided from the pulley.
The power is transmitted to the pulley installed in the.

Further, in this configuration, power is transmitted to the rotary mower device R mounted on the abdomen of the tractor by detouring the V belt via the front counter pulley.

Even in this case, the HST type transmission H and the traveling drive transmission M can use the same thing.

(F) Effects of the Invention Since the present invention is configured as described above, it has the following effects.

First, in the power transmission structure of the tractor, the input transmission A, the traveling drive transmission M, and the work implement drive B are separately configured and attached in combination to provide the traveling power and the rear work implement drive. Since the mechanism and the mid-working machine drive mechanism are configured, the mounting height of each device and the front and rear mounting positions can be easily changed, and a mechanism that can be mounted on a wide variety of small tractors can be configured. Was completed.

Second, since the power from the engine E is once input to the input transmission A and branched in the direction of the HST type transmission H and the working machine drive B, the HST type transmission H and the working machine drive are driven. The positional relationship of the device B can be easily adjusted. The positional relationship between the engine E and the input transmission A can also be freely changed.

Thirdly, since the input transmission A, the work implement drive B, and the traveling drive transmission M are separately provided, even if the tractor is attached to a slightly different type of tractor, the assembly of the power transmission structure is used and the universal By changing the length and position of the joint shaft, it can be attached to tractors of various models and specifications, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an overall side view of a tractor of the present invention, FIG. 2 is a side view of a power transmission structure which is an essential part of the present invention, and FIG. 3 is a side sectional view of a portion of a working machine drive device B, and FIG. Is also a rear view, FIG. 5 is a side view showing another structure for mounting the traveling drive transmission M on the tractor, and FIG. 6 is also a traveling drive transmission M.
FIG. 7 is a side view showing another configuration in a state where the arrangement of the HST type transmission H and the transmission is changed. A: Input transmission device B: Working device drive device C: Dry clutch device R: Rotary mower device 1 ... Cooling fan 3 ... Machine frame 4 ... Input shaft 5 ... Pump shaft 6 ... Working device Hydraulic pump for drive

Claims (1)

[Claims] 1. An HST type transmission H having a hydraulic pump 11 having a vertical axis and a hydraulic motor 12 arranged side by side is mounted on an upper portion of a traveling drive transmission M in which left and right drive axles 7 are projected.
A motor shaft protruding downward from the hydraulic motor 12 is inserted into the traveling drive transmission M to transmit power, and the hydraulic pump 11
The pump shaft 5 projecting up and down allows the working machine driving hydraulic pump 6 to be attached to the lower projection, the input transmission A to the upper projection, and the input transmission A to the front. Power is transmitted from the engine E to the projecting input shaft 4 via the universal joint shaft 2, and the bevel gear on the input shaft 4 and the bevel gear on the upper end of the pump shaft 5 are meshed with each other, and the input shaft 4 receives the input transmission device A. A power transmission structure for a tractor, which is configured to transmit power to a work implement drive device B from a portion protruding rearward from the work implement drive device B.