JPS6218128Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a steering device for a crawler-type traveling vehicle equipped with crawlers.

Among crawler-type vehicles, bulldozers and combine harvesters are slow, so there is no danger in steering by operating the left and right steering clutch levers as before, but in the case of a truck equipped with a crawler, the transport efficiency In order to increase speed, the vehicle must be at a certain speed, so it is a high-speed vehicle, and since it is often driven on public roads, there are many chances to pass other vehicles, and the left and right clutch levers are not used as in the past. Steering operations that involve alternating pull and pull operations have a high risk of causing a serious accident due to incorrect steering.

In this invention, in order to change the steering operation by alternately pulling the left and right clutch levers to the steering operation using a round handle, a conch-shaped cam is installed at the bottom of the round handle to rotate the roller and arm. This is what I did.

In addition, the cam always has a rotation limit angle, and if it rotates beyond that angle, the contact surface of the cam will return to its initial position, causing the travel clutch to suddenly engage or the travel brake to be released. be. In order to prevent such a dangerous situation from occurring, a stopper is required at the cam's rotation limit angle.
In the present invention, the stopper also serves as the terminal step of the conch-shaped cam.

The purpose of the present invention is as described above, and the structure of the present invention will be explained based on the structure of the embodiment shown in the attached drawings.

FIG. 1 is a plan view of the crawler-type transport vehicle, and FIG. 2 is a side view of the same.

A round steering wheel 2 is provided in the driver's cab 1, and an engine 4 is disposed below a seat 3. A clutch housing 7 is fixed to the rear of the engine 4, and power is transmitted to a transmission case 10 by a transmission shaft 8 protruding from the clutch housing 7. A drive shaft protruding to the left and right from the transmission case 10 drives a drive sprocket 6 to rotate the crawler 5. The loading platform 9 is configured to enable dumping operations.

FIG. 3 is a side sectional view of the main part of the steering device of the present invention, FIG. 4 is a plan view of the same, and FIG. 5 is a skeleton diagram of the steering clutch/brake section.

First, the steering clutch/operational brake device will be explained with reference to FIG.

The left and right drive sprockets 6L, 6R are interlocked by a drive shaft from final reduction gears 22L, 22R. The final reduction gears 22L and 22R are small diameter gears 25
Clutch bodies 24L and 24R are provided on L and 25R so as to be able to slide into and out of engagement. Further, the clutch bodies 24L, 24R also serve as brake shafts, and are configured to perform braking between the friction plates coming out of the brake drums 13L, 13R and the friction plates coming out of the clutch body.

The clutch bodies 24L and 24R are hydraulic pistons 2
3L, 23R or a link device, the clutch is first disengaged, and then the brake is applied.

In the present invention, the conch-shaped cam for sliding the clutch body can be operated with the round steering wheel 2, and the steering operation can be performed by rotating the round steering wheel like in a car. If the handle rotates too much, it will rotate beyond the operating angle of the cam, so the idea is to stop the rotation of the round handle when the cam reaches its full operating angle.

This will be explained in detail with reference to FIGS. 3 and 4. The steering round handle 2 is connected to a round handle shaft 2b via a mounting body 2a. Conch-shaped left and right steering cams 11 and 12 are fixed to the round handle shaft 2b in opposite positions with an interval between them. A roller 14 is in contact with the conch-shaped steering cam 11, and a roller 15 is in contact with the steering cam 12.

The roller 14 is pivotally connected to the middle part of the arm 16, and the roller 15 is pivotally supported to the middle part of the arm 17. The arm 17 has one end pivotally supported by a pin 26, is rotated by the steering cam 12, operates a hydraulic cylinder 21 pivotally connected by a pin 17b at the tip, and pressurized oil discharged from the hydraulic cylinder 21 is rotated by the steering cam 12. The oil is sent through a pipe to operate the hydraulic piston 23L for the clutch body 24L shown in FIG. 5 inside the transmission case.

The arm 16 is also pivoted at one end with a pin 26,
A hydraulic cylinder 20 is pivotally connected to the pin 16a at the other end. The pressure oil discharged by the operation of the hydraulic cylinder 20 is sent through a pipe to operate the hydraulic piston 23R shown in FIG.
The sliding part operates to disengage the clutch and apply the brake.

In this steering operation, the operating angle of the cams 11 and 12 is less than 360 degrees, and if the cams 11 and 12 rotate more than that, the rollers will return to their original positions at the terminal step as soon as they pass through the maximum diameter part of the conch shape. This can cause the brakes to suddenly release or the steering clutch to engage. In order to control this situation, it is necessary to prevent the round handle from rotating any further after the round handle shaft has rotated 360 degrees.

In the present invention, the operation is performed by the same rollers 14 and 1.
5 and conch-shaped steering cams 11 and 12.

As it rotates in the direction of the arrow as shown in FIG. 4, the protrusion 11a of the conch-shaped cam 11 pushes out the roller 14, and when the arm 16 has fully rotated, the opposite step of the conch-shaped steering cam 12 12b hits the roller 15, and since the stepped portion 12b is a steep stepped portion that does not form a cam surface, the roller 15 acts as a stopper to prevent further rotation of the round handle 2.

When you rotate the round handle 2 in the opposite direction of the arrow,
When the protrusion 12a of the steering cam 12 fully pushes out the roller 15, the stepped portion 11b of the cam 11 is blocked by the roller 14, and further rotation is prevented. Due to this structure, the round handle 2
It is becoming impossible to rotate more than 360 degrees.

Reference numerals 20 and 21 are hydraulic cylinders that are operated by hydraulic pressure, but the arms 16 and 17 may be connected to Bowden wires 18 and 19 so as to be operated by Bowden wires.

As described above, the present invention provides a crawler-type traveling vehicle equipped with a round steering wheel 2, in which the left and right steering cams 11, 1 in the shape of a conch shell are mounted on the round steering wheel shaft 2b.
2, and the two cams 11 and 12 are arranged vertically symmetrically, and the rotation of the cams 11 and 12 causes the rollers 14 and 15 and the arms 16 and 17 to rotate, thereby controlling the steering clutch and the steering wheel. The brake is configured to operate in parallel, and at the position where the roller reaches the operating angle limit of the maximum conch diameter portion of one cam, the stepped portion at the end of the conch shell of the other cam engages with the other roller. With this arrangement, the following effects can be achieved.

First, since the crawler-type traveling device can be steered using a round steering handle, it is possible to turn at a delicate turning angle, making it easy to use when driving a high-speed crawler-type transport vehicle on the road. This also eliminates accidents such as overturning due to the turning radius being too small, which is the case with conventional steering operations using left and right travel levers.

Second, when the rotation of a round steering handle is transmitted to a cam and the rotation of the cam is used to operate a hydraulic cylinder or wire, if the steering wheel is rotated beyond the rotation limit angle of the cam, sudden operation may occur. Although it may return to the initial state when the opposite clutch is connected or the brake is released, in this invention, by using a conch-shaped cam, one of the conch-shaped cams reaches its maximum diameter position. In this case, the largest diameter rear stepped portion of the other symmetrically arranged cam is locked to the roller, causing the left and right conch-shaped cams to move toward each other and the rotation stopper of the other cam. Therefore, there is no need to provide a separate stopper, and the round handle automatically becomes unable to rotate at its rotation limit, so if it rotates beyond that limit, the steering clutch will engage or the brakes will fail. It will never be canceled.

[Brief explanation of the drawing]

Figure 1 is a plan view of the crawler-type transport vehicle, Figure 2 is a side view, Figure 3 is a sectional side view of the main parts of the steering system of the present invention, Figure 4 is a plan view, and Figure 5 is a side view of the steering system. FIG. 3 is a skeleton diagram of the opposite clutch/brake section. 2... Round steering wheel, 2b... Round handle shaft, 11, 12... Steering cam, 14, 15...
Roller, 16, 17...arm.

Claims (1)

[Scope of utility model registration request] In a crawler type vehicle equipped with a round steering handle 2, conch-shaped left and right steering cams 11 and 12 are provided on the round handle shaft 2b, and the two cams 11 and 12 are positioned symmetrically in the vertical and horizontal positions. The rotation of the cams 11 and 12 rotates the rollers 14 and 15 and the arms 16 and 17 to operate the steering clutch and the steering brake in parallel, and the diameter of the conch shell of one of the cams is A steering device for a crawler-type traveling vehicle, characterized in that a stepped portion at the end of the conch shell of the other cam is arranged to engage with another roller at a position where the roller reaches its maximum operating angle limit.