JPH063889Y2 - Hydraulic circuit of backhoe with angled - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a crawler type traveling device equipped with an angle dozer, and a swivel base equipped with a backhoe device, a boarding operation part, and a driving part. First and second hydraulic pumps connected to first and second traveling hydraulic motors that drive the left and right crawlers separately, first and second traveling operation valves that individually operate the left and right crawlers, and operation of the backhoe device Valve, the operation valve of the swivel base, and the operation valve of the angle dozer are provided on the swivel base, and the hydraulic pressures from the first and second operation valves are separately supplied to the first and second traveling hydraulic motors. A hydraulically operated high / low speed switching valve that merges with the running state and switches to a high-speed running state that is supplied in series, and a dozer lifting hydraulic cylinder that raises and lowers the angle dozer and an angle adjustment hydraulic pressure that changes the horizontal direction. A Linda is provided in the traveling device, and a high / low speed switching operation valve is provided on the swivel base for switching the high / low speed switching valve to a high speed traveling state against a return spring by applying operating pressure. Operating valve,
The present invention relates to a hydraulic circuit of a backhoe with an angle dozer, in which a rotary joint that allows rotation of the swivel is interposed in an oil passage connected to the operation valve for the angle dozer and the operation valve for switching between high speed and low speed.

[Conventional technology]

Conventionally, as shown in FIG. 3, the operation valve (V ₁₂ ) for the high / low speed switching valve (V ₁₁ ) is connected to the first hydraulic pump (P ₁ ) connected to the first traveling operation valve (V ₁ ). In addition, the hydraulic cylinder (C ₁ ) for the boom, arm, and bucket of the backhoe device,
Connect the operating valves (V ₃ ), (V ₆ ), (V ₇ ) to (C ₂ ), (C ₃ ),
The second hydraulic pump (P ₂ ) connected to the _second operation valve (V ₂ ).
, The operating valve of the swing motor _{(M 3) (V 8)} , operating valves of a swing hydraulic cylinder (C ₄₎ with respect to backhoe implement (V _9), the boom and the hydraulic cylinder for arm (C _1), (C ₂ ) Operating valve (V ₄ ),
(V ₅ ) is connected to the operating valve of the hydraulic cylinder (C ₅ ) for lifting the dozer.
(V ₁₅ ) and operating valve (V ₁₆ ) for hydraulic cylinder (C ₆ ) for angle adjustment
Was installed on the swivel base and was connected to the third hydraulic cylinder (P ₃ ).

[Problems to be solved by the invention]

However, two dozer operating valves (V ₁₅ ) and (V ₁₆ ) for raising and lowering the dozer and for adjusting the angle are provided on the swivel base, and four operating valves (V ₁₅ ) and (V ₁₆ ) are connected to each other. Since the oil passage of is formed in the rotary joint (15),
The number of oil passages (15), including those for drains, is as large as 10, and there is a drawback that the rotary joint (15) becomes expensive due to the complicated oil passage structure. In addition, the hydraulic structure for adjusting the angle of the dozer is generally not a standard equipment, and therefore, only eight oil passages are formed in the standard of the rotary joint (15), and the hydraulic structure for adjusting the angle is required by the user. When adding, use the rotary joint (1
There is a drawback that the replacement of 5) is necessary, which also increases the cost.

The object of the present invention is to use a rotary joint, which is a standard product with eight oil passages, and to provide a hydraulic structure for adjusting the angle of the dozer so that the rotary joint can be inexpensive and the standard type. The point is to make it possible to modify the backhoe with a dozer at a low cost.

[Means for solving problems]

The characteristic configuration of the present invention is a hydraulically operated target selection valve for selectively connecting a dozer lifting hydraulic cylinder and an angle adjusting hydraulic cylinder to one angle dozer operating valve provided on a swivel base. , A crawler type traveling device is provided with a hydraulically operated automatic valve for connecting the target selecting valve to the angle adjusting hydraulic cylinder in a connected state against a return spring by applying an operating pressure, and for switching between high speed and low speed to the traveling device. Connect the automatic valve on the traveling device side rather than the rotary joint to the operation oil passage that connects the operation valve and the high-low speed switching valve that will be in a high-speed traveling state when hydraulically operated by the operation valve, and connect the left and right crawlers. First and second operations that can be operated separately
Provided is a hydraulic operation circuit that applies hydraulic pressure from at least one of the traveling operation valves to the automatic valve as an operation pressure to make the target selection valve connected to the dozer lifting hydraulic cylinder against a return spring. That is, the action and effect are as follows.

[Action]

That is, when the first traveling operation valve or the second traveling operation valve is opened and the traveling device is driven, the automatic valve is closed by the hydraulic pressure from the hydraulic operation circuit, and the target selection valve is the return spring and the dozer lifting hydraulic cylinder. It is connected to and can be operated to raise and lower the dozer by the operation valve for the angle dozer.

Further, since the automatic valve is closed regardless of whether the high-low speed switching operation valve is in the low speed traveling state or the high speed traveling state, the dozer can be moved up and down by the angle dozer operation valve.

When the traveling device is stopped by closing the first and second traveling operation valves, the automatic valve is opened by the return spring and connected to the target selection valve. Therefore, when the high / low speed switching operation valve is closed and the high / low speed switching valve is set to the low speed traveling state, the operation pressure from the operation oil passage for the high / low speed switching valve is not applied to the target selection valve, so the target selection valve Is connected to the hydraulic cylinder for raising and lowering the dozer, and the operating valve for the angle dozer can be used to raise and lower the dozer. Then, open the high / low speed switching operation valve,
When the high-low speed switching valve is set to the high-speed running state, the operating pressure from the operating oil passage for the high-low speed switching valve is applied to the target selection valve, and the target selection valve is connected to the angle adjustment hydraulic cylinder of the dozer, The dozer operating valve allows for lateral adjustment of the dozer.

In short, the dozer can be adjusted to the right and left only when the traveling is stopped and the high-low speed switching valve is brought into the high-speed traveling state, and the dozer can be moved up and down at other times.

As described above, when the target selection valve and the automatic valve provided in the traveling device are used, and the target selection valve and the automatic valve are operated by using the high / low speed switching hydraulic pressure and the driving hydraulic pressure of the traveling device. By installing only one angle dozer operating valve on the swivel base, the dozer can be moved up and down and the dozer horizontal direction can be adjusted, and the oil passage of the rotary joint between the traveling device and the swivel base can be hydraulically configured to adjust the dozer horizontal direction. The same number as 8 without
Can be a book

[Effect of device]

As a result, the oil passage structure of the rotary joint can be simpler and cheaper than that of the above-mentioned conventional technique, and the oil pressure structure for angle adjustment is eliminated, and the rotary joint has eight oil paths. Although the configuration is optional, the option can be added by inexpensive modification without changing the rotary joint, and as a whole, the backhoe with the angle dozer having the hydraulic configuration for angle adjustment can be provided at a lower price than before. .

〔Example〕

 Next, examples will be shown.

As shown in FIG. 2, a backhoe device (3), a boarding operation part (4) and a driving part (5) are provided on a swivel base (2) attached to the crawler type traveling device (1), and the traveling device (1) is provided. An angle dozer (7) is attached to a dozer arm (6) that is swingable up and down, and the angle dozer (7) can be freely changed in the left and right directions to form a backhoe with an angle dozer for excavation work, earth removal work, snow removal work, and the like.

The boom (3a) and the arm (3
b), equipped with hydraulic cylinders (C ₁ ) to (C ₃ ) for driving the bucket (3c) separately, and swing swing bracket (8) with boom (3a) attached can be swung left and right with hydraulic cylinder (C ₄ ). Swivel on (2)
It is attached to.

Dozer lifting hydraulic cylinder (C ₅ ) for lifting the angle dozer (7) and angle adjusting hydraulic cylinder for changing the horizontal direction
(C ₆₎ a travel device (1) first and second traveling hydraulic motor for driving right and left crawlers to each other (M _1), (M ₂₎ of the traveling device (1)
, A swivel base (2) is provided with a swivel hydraulic motor (M ₃ ) for rotating the swivel base (2) .The hydraulic cylinders (C ₁ ) to (C
₆ ) and hydraulic circuits for hydraulic motors (M ₁ ) to (M ₃ )
This will be described below with reference to FIG.

The first to third hydraulic pumps (P ₁ ) to (P ₃ ), the oil tank (T), the first and second traveling operation valves (V ₁ ), (V ₂ ), which operate the left and right crawlers separately, and the backhoe. Operating valve of device (3)
(V ₃ ) to (V ₇ ), operation valve (V ₈ ) of swivel base (2), operation valve of swing bracket (8) (V ₉ ), operation valve of angle dozer (7)
(V ₁₀ ) is provided on the swivel base (2), and the operating valves (V ₁ ) to (V ₁₀ ) can be operated by the lever of the boarding operation unit (4). The two boom operating valves (V ₃ ) and (V ₄ ) and the arm operating valves (V ₅ ) and (V ₆ ) are operated in conjunction with each other, and the other operating valves
(V ₁ ), (V ₂ ), (V ₇ ), (V ₈ ), (V ₉ ) (V ₁₀ ) are operated separately.

Connect the first travel operation valve (V ₁ ), boom operation valve (V ₃ ), arm operation valve (V ₆ ), bucket operation valve (V ₇ ) to the first hydraulic pump (P
₁ ), operating valve for second travel (V ₂ ), operating valve for boom (V _2
4 ), arm operation valve (V ₅ ), swing operation valve (V ₈ ), swing operation valve (V ₉ ) are connected to the second hydraulic pump (P ₂ ), and the angle dozer operation valve (V ₁₀ ) Is connected to the third hydraulic pump (P ₃ ).

The hydraulic pressure from the first and second traveling operation valves (V ₁ ) and (V ₂ ) is used as the first
And a hydraulically operated high / low speed switching control valve (V ₁₁ ) that switches between a low speed running state in which it is separately supplied to the second hydraulic motors (M ₁ ) and (M ₂ ) and a high speed running state in which it merges and is supplied in series. An operation valve for high / low speed switching, which is provided in the device (1), and which puts the high / low speed switching valve (V ₁₁ ) in a high speed running state against the return spring (S ₁ ) by applying the operating pressure from the first pump (P ₁ ). (V ₁₂ ) is provided on the swivel base (2) so that it can be opened by stepping on the restoration type pedal to enable two-speed gear shifting of traveling.

Six oil passages connected to each of the first and second traveling operation valves (V ₁ ), (V ₂ ), the angle dozer operation valve (V ₁₀ ), and the high / low speed switching operation valve (V ₁₂ ) Connected to one operating oil passage (9),
A rotary joint (11) allowing rotation of the swivel base (2) is interposed in a total of eight oil passages of one drain passage (10) for returning drain oil to the tank (T).

Hydraulic valve for raising and lowering dozer (C ₅ ) and hydraulic cylinder for adjusting angle (C ₅ ) for one operation valve (V ₁₀ ) for angle dozer
₆ ) Hydraulically operated target selection valve for selectively connecting
(V ₁₃ ) and the target selection valve (V ₁₃ ) are connected to the angle adjusting hydraulic cylinder (C ₆ ) against the return spring (S ₃ ) by applying the operating pressure by the oil passage (12). A hydraulically operated automatic valve (V ₁₄ ) is installed on the traveling device (1).

An automatic valve (V ₁₄ ) on the travel device (1) side of the rotary joint (11) in the operation oil passage (9) connecting the high / low speed switching operation valve (V ₁₂ ) and the high / low speed switching valve (V ₁₁ ). Are connected by an oil passage (13), and the hydraulic pressure from the first travel operation valve (V ₁ ) is applied as an operation pressure to the automatic valve (V ₁₄ ) to resist the return spring (S ₂ ) and select the target. A hydraulic operating circuit (14) is provided for connecting the valve (V ₁₃ ) to the dozer lifting hydraulic cylinder (C ₆ ).

That is, the traveling device (1) is stopped and the high / low speed switching valve (V
The hydraulic pressure from the first pump (P ₁ ) is applied as an operating pressure to the target selection valve (V ₁₃ ) only when ₁₁ ) is in a high-speed traveling state, and the angle is adjusted by the angle dozer operating valve (V ₁₀ ). The hydraulic cylinder (C ₆ ) for operating the dozer can be operated with the operating valve for the angle dozer (V ₁₀ ) when the operating valve for high / low speed switching (V ₁₂ ) is not operated during running or stopping. ₅ ) can be operated.

A shuttle valve (14a) for applying an operating pressure to the automatic valve (V ₁₄ ) in the hydraulic operation circuit (14) during both forward rotation and reverse rotation of the first traveling hydraulic motor (M ₁ ), and , The throttle (1 for releasing the operating pressure when the first traveling hydraulic motor (M ₁ ) is stopped
4b) A drain passage is provided.

[Another embodiment]

 Next, another embodiment will be described.

Number of operation valves (V ₃ ) to (V ₇ ) of backhoe device (3) and pump
The connection relation to (P ₁ ) and (P ₂ ) can be freely changed. For example, boom operating valves (V ₃ ), (V ₄ ) and arm operating valves (V ₅ ), (V ₆ ).
May be one.

The swing operation valve (V ₈ ) may also be used for the swing, and the swing operation valve (V ₉ ) may be omitted, or the swing hydraulic cylinder (C ₄ ) may be omitted.

The high / low speed switching operation valve (V ₁₂ ) is the second hydraulic pump (P ₂ ) and the third
It may be connected to a hydraulic pump (P ₃ ) and its operating valve (V
The operation configuration of ₁₂ ) may be a lever type.

The hydraulic operation circuit ( ₁₄ ) for the automatic valve (V ₁₄ ) can be appropriately changed in the concrete configuration, and either one or both of the first and second traveling operation valves (V ₁ ) and (V ₂ ) can be used. All you need is a connection.

The angle dozer operation valve (V ₁₀ ) may be connected to the first hydraulic pump (P ₁ ) or the second hydraulic pump (P ₂ ), and the third hydraulic pump (P ₃ ) may be omitted.

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

[Brief description of drawings]

1 and 2 show an embodiment of the present invention. FIG. 1 is a hydraulic circuit diagram and FIG. 2 is a side view of a backhoe. FIG. 3 is a hydraulic circuit diagram of a conventional example. (1) …… Traveling device, (2) …… Swivel base, (3) …… Backhoe device, (4) …… Boarding operation part, (5) …… Driving part, (7) …… Angle dozer, ( 9) …… Operating oil passage, (11) …… Rotary joint,
(14) …… Hydraulic operation circuit, (C ₅ ) …… Dozer lifting hydraulic cylinder, (C ₆ ) …… Angle adjusting hydraulic cylinder, (M ₁ ), (M
₂ ) …… Traveling hydraulic motor, (P ₁ ), (P ₂ ) …… hydraulic pump, (V ₁ ), (V ₂ ) …… Traveling operation valve, (V ₃ )-(V ₇ ) …… Backhoe operating valve, (V ₈ ) …… Swivel operating valve, (V ₁₀ ) …… Angle dozer operating valve, (V ₁₁ ) …… High / low speed switching valve, (V ₁₂ )…
… High / low speed switching control valve, (V ₁₃ ) …… Target selection valve, (V ₁₄ )
...... Automatic valve, (S ₁ ) to (S ₃ ) …… Return spring.

Claims (1)

[Scope of utility model registration request] 1. A crawler type traveling device (1) equipped with an angle dozer (7), and a swivel base (2) equipped with a backhoe device (3), a boarding operation part (4) and a driving part (5). , The traveling device (1)
First and second hydraulic pumps connected to first and second traveling hydraulic motors (M ₁ ) and (M ₂ ) for separately driving the left and right crawlers of the vehicle
(P ₁ ), (P ₂ ), first and second traveling operation valves (V ₁ ), (V ₂ ), which individually operate the left and right crawlers, the backhoe device
(3) of the operating valve (V ₃₎ ~ (V _7), said swivel base (2) of the operating valve (V _6),
Set the operation valve (V ₁₀ ) of the angle dozer (7) to the swivel base (2).
And a low speed for supplying pressure oil from the first and second operation valves (V ₁ ) and (V ₂ ) to the first and second traveling hydraulic motors (M ₁ ) and (M ₂ ) separately A hydraulically operated high / low speed switching valve (V ₁₁ ) that switches to a high-speed traveling state where it merges with the traveling state and is supplied in series, and a dozer lifting hydraulic cylinder (C ₅ ) that lifts and lowers the angle dozer (7) The angle adjusting hydraulic cylinder (C ₆ ) to be changed is provided in the traveling device (1), and the high / low speed switching valve (V ₁₁ ) is applied to the return pressure (S ₁ ) by the application of the operating pressure to bring the high speed traveling state. A high / low speed switching operation valve (V ₁₂ ) is provided on the swivel base (2), and the first and second traveling operation valves are provided.
(V ₁ ), (V ₂ ), the angle dozer operation valve (V ₁₀ ) and the high / low speed switching operation valve (V ₁₂ ) are allowed to rotate in the oil passage connected to the swivel base (2). In a backhoe with an angle dozer having a rotary joint (11) interposed between the dozer lifting hydraulic cylinder (C ₅ ) and the angle adjusting hydraulic cylinder (C) with respect to one angle dozer operating valve (V ₁₀ ). ₍₆ ) Hydraulically operated target selection valve (V
₁₃ ) and its target selection valve (V ₁₃ ) are connected to the angle adjusting hydraulic cylinder (C ₆ ) against the return spring (S ₂ ) by applying operating pressure. (V
₁₄ ) is provided in the traveling device (1), and the high / low speed switching operation valve is provided.
(V ₁₂₎ and the operating oil passage for connecting the high-low speed switching valve (V ₁₁₎
The automatic valve (V ₁₄ ) is connected to (9) on the traveling device (1) side of the rotary joint (11), and the first and second traveling operation valves (V ₁ ) and (V ₂ ) are connected. ) Is applied to the automatic valve (V ₁₄ ) as an operating pressure to the return valve (S ₃ ), and the target selection valve (V ₁₃ ) is moved to the dozer lifting hydraulic cylinder (C). ₅ ) A hydraulic circuit for a backhoe with an angle dozer, which is provided with a hydraulic operation circuit (14) for connection with the backhoe.