JPH042136Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention biases a pair of left and right disk-type steering clutches, which individually disconnect and disconnect power transmission to a pair of left and right traveling devices, to the power transmission side. The present invention relates to a steering operation section for a working vehicle, which is provided in a state in which the clutches are engaged, and is provided with separate operation tools for each of the clutches.

[Conventional technology]

Conventionally, the above-mentioned work vehicles have adopted a so-called power steering type in which the clutch disengagement force from the steering tool is increased by a hydraulic power cylinder and transmitted to the disc type steering clutch, or In order to respond to the user's request for a model that simply transmits the clutch disengagement operating force to the steering clutch via a link mechanism, the specifications are completely different for almost the entire range from operation to the operating part of the steering clutch. The manufacturer had prepared two types of interlocking configurations.

In other words, the interlocking ratio in the interlocking configuration is different when using a power cylinder and when simply using a link mechanism for transmitting operating force.
Furthermore, when operating the steering clutch, which is biased toward the power transmission side, it is generally reasonable to operate the power cylinder on the extension side, whereas it is appropriate to simply apply the switching force using the link mechanism. In the case of transmission, it is advantageous in terms of link strength to transmit the cutting operation force by tension in order to transmit a large operating force that overcomes the clutch's engagement biasing force. A completely different interlocking configuration had to be prepared depending on the model.

[Problem that the invention attempts to solve]

However, even though the working vehicle models are the same, it is necessary for the manufacturer to prepare configurations with two completely different specifications as described above for the overall steering operation configuration from the operating tool to the clutch. This was extremely disadvantageous in terms of production costs, inventory management, and production costs.

The purpose of the present invention is to provide a rationally improved configuration that allows the power steering type and the link interlocking type to be changed by simply recombining one component, without having to recombine the entire operating configuration from the operating tool to the clutch operating section. The purpose of this invention is to enable configuration of two specifications and to facilitate manual operation.

[Means for solving problems]

In order to achieve the above object, the steering operation section of the working vehicle according to the present invention has the above-mentioned structure.
an operating arm operatively connected to the operating tool; and
Each of the operated arms interlocked with the operating portion of the clutch is swingably provided with their longitudinal intermediate portions as a pivot point, and the clutch cutting operation force from the operating tool is applied to one end of each arm. A connecting portion is provided for the pressing type power cylinder that increases the power, and a connecting portion for a link that transmits the clutch cutting operation force from the operating tool by tension is provided at the other end of both arms, and the operating side The length between the pivoting center of the arm and the connecting portion of the operating arm of the link is set to be smaller than the length between the pivoting center of the operated arm and the connecting portion of the link. The characteristic configuration is that

The functions and effects of this characteristic configuration are as follows.

[Effect]

In other words, with the above configuration, regardless of the power steering type and link interlocking type, the power cylinder alone as one component can be assembled between the two arms that were previously assembled, or the power cylinder can also be one component. Either a power steering type or a link interlocking type can be configured by simply selecting whether to assemble the link.

In addition, when selectively configuring these types, the power cylinder acts on the extension side (pressure side) in a logical manner as before when the steering clutch is disengaged against the biasing force. In addition, since the link acts on the tensile side, which is advantageous in terms of strength, there is no need to use a special specification power cylinder.
In addition, in terms of the overall strength of the operation configuration, when installing the link, the length between the connecting point of the link on the operating side arm and the pivot point of the operating side arm is determined by the length of the link on the operated arm. Since the length is set smaller than the length between the connecting point and the pivot point of the operated arm, the lever can be operated easily.

[Effect of idea]

As a result of the above, there are improvements in human operability, strength, and
Although the specifications of the power cylinder itself are the same as before, the power steering type and link interlocking type are assembled as a single power cylinder in a state where most of the operating configurations are shared regardless of the type. Since the structure can be configured by simply selecting and assembling one component, either attaching the link or assembling a single link, it is extremely advantageous for the manufacturer in terms of production, production cost, and inventory management. Even when the machine is in use, it can be operated easily without requiring much operating force.

〔Example〕

Next, embodiments of the present invention will be described.

As shown in FIGS. 2 and 3, for a pair of left and right multi-wheel traveling devices 1, a dump platform 2 and a
In a rough terrain transport vehicle equipped with a boarding and driving section 3, a pair of left and right vehicle body frames 5 supporting a plurality of drive wheels 4 on each of the left and right sides of the vehicle body are connected to the supporting wheels 4.
A disc-type steering clutch 7 is configured to also serve as a transmission case for the transmission cases 6 and to separately connect and disconnect power transmission to each transmission case 5 in each of the interlocking systems that separately transmit power from the transmission case 6 to the left and right transmission cases 5. A pair of left and right steering levers 8 provided on the driving section 3 are used to separately operate the left and right steering clutches 7 to control the direction of the vehicle.

The steering clutch 7 is always biased toward the power transmission side, that is, the input side, by a biasing mechanism such as a spring, and the contact friction force on the disk surface supported by the biasing force causes the steering clutch 7 to be biased toward the power transmission case 5 side. Power is transmitted to.

A first
As shown in FIG. 1 and FIG. 2, the operating arm 12 is interlocked with the operating lever 8 via the first bell crank mechanism 9, the first push/pull rod 10, and the second bell crank mechanism 11, and the third The operating arm 7a of the steering clutch 7 via the bell crank mechanism 13, the second push/pull rod 14, and the universal joint mechanism 15.
and the operated side arm 16 interlocked with the
The intermediate portions in the longitudinal direction thereof are pivot points P ₁ and P ₂ and are swingably provided.

Both swinging end sides 12 of the operating arm 12
a, 12b, the first swinging end 12a is the side that swings toward the operated arm 16 in response to the clutch release operation of the operating lever 8, and both ends 16a of the operated arm 16, 16b, the second swinging end side 16a on the side where the swinging direction for clutch disengagement operation is away from the operating arm 12 is on the same side with respect to the imaginary straight line connecting the pivot points P ₁ and P ₂ . The input rod 17a of the power cylinder 17, which increases the cutting force from the operating lever 8 by extension, is attached to the first swinging end side 12a of the operating arm 12. and the second swinging end side 16a of the operated side arm 16 to the power cylinder 1.
Connecting portions 18b are provided for the output rods 17b of 7, respectively, and the cutting operation force from the operating lever 8 is applied to the third swinging end side 12b, which is the other swinging end side of the operating arm 12. A connecting portion 20a to one end of the push/pull link 19 transmitting
and a connecting portion 20b for the other end of the push/pull link 19 is provided on the fourth swinging end side 16b, which is the other swinging end side of the operated arm 16.

That is, either a pressing power cylinder 17 is interposed between the first swinging end side 12a and the second swinging end side 16a, or the third swinging end side 12b and the fourth swinging end side Push-pull link 1 between end side 16b
By selecting whether or not 9 is to be installed, it is possible to easily configure either a so-called power steering type or a simple link interlocking type as a steering operation configuration.

As shown in FIG. 4, the input rod 17a of the power cylinder 17 is interlocked with its internal valve mechanism 17c, and as the input rod 17a is pushed in, the output rod 17b is moved. In addition, as the input rod 17a is pulled out, the output rod 17 is extended.
The configuration is such that shortening of b is allowed.
Furthermore, when the power cylinder 17 is installed, the power cylinder 17 main body is fixed to the vehicle body.

Third swinging end side of operating arm 12, 1
The arm length l ₁ of the arm 2b is set to be smaller than the arm length l ₂ of the fourth swinging end side 16b of the operated arm 16, and thereby the push-pull link 19 is used instead of the power cylinder 17. In the case of a link-interlocking type in which the clutch is interposed, the manual operation force required for the clutch disengagement operation is reduced.

the power cylinder 17 for steering operation, and
To configure the hydraulic circuit for the cylinder 21 for driving the dump platform 2, as shown in FIG. are connected in parallel to each other via a priority valve 23, and the steering power cylinder 1
By preferentially supplying pressure oil from the pump 22 to the engine 7, stable steering operation can be performed regardless of fluctuations in the engine E rotation speed.

Furthermore, between the priority valve 23 and the steering power cylinder 17, a flow divider valve 24 is provided to evenly distribute the pressure oil from the priority valve 17 to the left and right steering power cylinders 17. It is installed in the oil line.

On the other hand, between the priority valve 23 and the dump hydraulic cylinder 21, a dump operation valve 25 is interposed in the oil passage, and a relief valve 26 is provided, and a relief valve 26 is provided in the oil drainage passage. An oil cooler 27 is interposed.

In other words, in this hydraulic circuit configuration, the transmission case 6 is also used as the hydraulic oil tank T, but the dump cylinder 21 consumes a larger amount of oil than the hydraulic system of the steering power cylinder 17.
By attaching the oil cooler 27 to the hydraulic system, the rise in oil temperature in the hydraulic oil tank T, that is, the rise in the temperature of the oil stored in the transmission case 6, can be effectively suppressed with one oil cooler 27. It's like this.

[Another example]

Next, another embodiment of the present invention will be described.

In the above-mentioned steering operation configuration, the specific interlocking structure between various types of steering operating tools 8 such as levers and the operating arm 12, and the interlocking structure between the operating section 7a of the disc type steering clutch 7 and the operated arm 16 are explained. Various improvements can be made to the specific interlocking structures.

First swing end side 12 of operating arm 12
The arm length of a and the arm length of the third swinging end side 12b, as well as the arm length of the second swinging end side 16a and the arm length of the fourth swinging end side 16b of the operated side arm 16. The specific dimensions and the ratio of the dimensions can be changed as appropriate, and the connection parts 18a, 18b, 20a for the power cylinder 17 or the push/pull link 19 provided on each swinging end side. ,2
The specific structure of 0b can also be improved in various ways.

The applicable steering power cylinder 17 is as follows:
Various types of devices can be used as long as they have an operating force input section on one end side and are driven to extend by pressing the input section.

The steering operation unit according to the present invention can be applied to work vehicles for various purposes as long as it is equipped with a pair of left and right disc-type steering clutches that separately connect and disconnect power transmission to the left and right traveling devices.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; Fig. 1 is a side view showing the steering operation configuration, Fig. 2 is a plan view thereof, Fig. 3 is an overall side view of the working vehicle, and Fig. 4 is a hydraulic circuit diagram. be. 1... Traveling device, 7... Steering clutch, 7a...
...Operation unit, 8...Operation tool, 12...Operation side arm, 16...Operated side arm, 17...Power cylinder, 18a, 18b...Connection part, 19...Link, 20a, 20b...Connection Part, P ₁ , P ₂ ...
Pivot point.

Claims (1)

[Scope of utility model registration request] A pair of left and right disc-type steering clutches 7 separately connect and disconnect power transmission to a pair of left and right traveling devices 1,
In a work vehicle equipped with separate operating tools 8 for each of the clutches 7, each of which is biased toward the power transmission action side, an operating arm 12 interlockingly connected to the operating tool 8 and the operation of the clutch 7 are provided. Part 7
Each of the operated side arms 16 interlocked with a is swingably provided with their longitudinal intermediate portions serving as pivot points P ₁ and P ₂ , and one end of each of the arms 12 and 16 is connected to the operating tool 8 . Connecting portions 18a and 18b to the pressing power cylinder 17 are provided to increase the clutch cutting operation force of the arms 12,
A link 19 that transmits the clutch cutting operation force from the operation tool 8 by tension to the other end side of each of 16.
The length between the pivot point P ₁ of the operating arm 12 and the connecting section 20a of the operating arm 12 of the link 19 is set to the operating arm 12. 16
The steering operation portion of the working vehicle is set to be smaller than the length between the pivot point P ₂ of the link 19 and the connecting portion 20b of the link 19.