JPH0322488B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an artificial valve that can be freely switched between forward and reverse drive and a stop position in a multiple valve with a center bypass for a hydraulic motor that rotates a swivel table equipped with a working device. A detector for detecting the angle of the swivel base relative to the vehicle body, a setting device for setting the position relative to the vehicle body at which the swivel base should be stopped, a device for detecting the operating direction of the operating tool of the manually operated valve, and the hydraulic motor. a valve for intermittent refueling, and a valve for automatically stopping the swivel base at the set position relative to the vehicle body based on information from the angle detector relative to the vehicle body and the operating direction detecting device; The present invention relates to a swing-type work vehicle for various uses, which is equipped with a control device for closing operation and can be easily turned to a predetermined position.

Conventionally, in the above-mentioned swing-type work vehicle, the hydraulic circuit is configured using a hydraulic motor 5, as shown in FIG.
A pair of oil passages 13a and 13b connecting the manually operated valve _V1 in the multiple valve V and the hydraulic motor 5 are used as a valve 14 for intermittent oil supply to the hydraulic motor 5 by synchronously switching between them. a pair of two-position switching electromagnetic valves 14a for switching the oil supply direction;
The oil supply to the hydraulic motor 5 was cut off by interposing separate solenoid valves 14b and switching only one of the electromagnetic valves 14a and 14b by the control device 19.
Since two electromagnetic valves 14a and 14b are required, the manufacturing cost is high.

An object of the present invention is to provide a revolving work vehicle that is practical and highly safe while reducing the number of valves through rational improvements.

A characteristic configuration of the present invention is that, in the above-mentioned swing-type work vehicle, the shutoff valve includes one valve of a forward/reverse drive and stop operation type disposed between the manually operated valve and the hydraulic motor; A mechanical interlocking mechanism is interposed between the valve and its operating tool so that the operating valve can be operated in one direction from the stopped position by either forward or reverse operation of the operating tool from the stopped position. In particular, its actions and effects are as follows.

In other words, by switching one 3-position switching type valve to the stop position by a command from the control device, the oil supply to the hydraulic motor is cut off and the swivel base is automatically stopped. The number of valves can be reduced compared to using two solenoid valves as on/off valves.

By the way, if the intermittent valve is composed of one valve,
It is also conceivable to switch between forward/reverse and stop using a manually operated valve in a multiple valve, and to perform automatic stop by automatically switching a single on/off valve interposed between this and the hydraulic motor. , Pressure oil is supplied to the oil drain port of the intermittent valve when the manually operated valve is in either the forward or reverse switching state. It cannot be used as a commercial valve, and therefore cannot be put to practical use.

In addition, as another means, a three-position switching type operation valve having the same structure as the above-mentioned manually operated valve and a three-position switching type for forward/reverse and stop switching interposed between it and the hydraulic motor are provided to be incorporated into a multiple valve. Each of the mold interrupting valves is connected to the operating tool via an automatic control device, and the switching valve is switched from the stop position to the forward/reverse position in response to the forward/reverse operation of the operating tool from the stop position. It is conceivable to configure the automatic control device so that the operation valve can only be operated in one direction from the stop position by either forward or reverse operation, but it is possible to configure the automatic control device so that the operation valve can only be operated in one direction from the stop position. Therefore, if a problem occurs in the operating circuit during the turning operation, there is a high risk that the turning table will not be able to be stopped, resulting in a lack of safety.

According to the present invention, the mechanical interlocking mechanism interposed between the operating tool and the operating tool allows the operating valve to be operated in only one direction regardless of whether the operating tool is operated in the forward or reverse direction from the stop position. , the oil drain port of the intermittent valve, which is configured as a three-position switching valve for forward/reverse and stop switching, can be used exclusively for oil drainage, making it possible to use a general specification valve as the intermittent valve, and ,
Even if a trouble occurs in the electrical operation circuit for the on/off valve, the operation valve can be manually operated to the stop position, which has the advantage of reliably stopping the swivel base.

In short, it has been possible to provide a revolving work vehicle that is practical and highly safe, while reducing the number of valves and greatly reducing manufacturing costs.

Next, examples will be shown.

FIG. 1 shows a swivel type excavation work vehicle, in which a swivel base 3 equipped with a boarding and driving unit 1 and a driving unit 2 is vertically connected by a hydraulic motor 5 to a machine base equipped with a pair of left and right crawler traveling devices 4. An excavation work device 8 is constructed by connecting a rotary bucket 7 to the tip of a working arm 6 which is attached to be able to rotate freely around an axis P ₁ and which can freely swing up and down as well as bend and extend. It is connected to the swivel base 3 via a swing bracket 9 that can be freely swung.

As shown in Fig. 2, a 3-position switch for rotation in a multiple valve V formed by connecting a plurality of operating valves V _{1, 2,} ... arranged side by side through a center bypass oil passage 12 from an operating pump 11 into a unit. The mold operation valve V ₁ and the hydraulic motor 5 are connected through reciprocating oil passages 13a and 13b, and the hydraulic motor 5 can be driven in forward and reverse directions as well as stopped.
motor 5 in the driving state.
A proportional pilot-operated three-position switching valve 14 that adjusts the amount of oil supplied to the return oil passages 13a, 13b
and a pair of proportional electromagnetically operated pilot valves 15a, 1 for the proportional switching valve 14.
5b is provided so that the branch pressure oil from the outgoing oil passage 13a is used as pilot pressure oil.

Even if the turning operation lever 16 is operated from the stop position N to either the forward or reverse drive operation position R or L, the operation valve V ₁ can only be moved in one direction from the neutral position. A device 18 for detecting the operating state of the operating lever 16 is attached to the valve operating structure 17, which is equipped with a mechanism 17A that interlocks both 16 and V ₁ so that the switching operation cannot be performed. based on,
in a direction corresponding to the operating direction of the lever 16, and
A control device 19 is provided for instructing the drive controller 15 of the pilot valves 15a, 15b to drive the hydraulic motor 5 at a speed corresponding to the amount of operation of the lever 16 from the stop position N.

In other words, by operating one lever 16, the pressure oil supply section can be controlled by the operation valve _V1 in the multiple valve V, and the rotation direction and speed of the swivel base 3 can be controlled by the proportional switching valve 14. There is.

When the manual/automatic changeover switch 20 attached to the control device 19 is in the automatic switching state, the rotation angle θ of the swivel base 3 relative to the machine base is given from the rotation angle detector 21 attached to the rotation shaft of the swivel base 3. information, and
A start command given from the operation state detection device 18,
In addition, based on the operation rotation direction information, after receiving the start command, rotate the swivel base 3 at a predetermined speed in the designated direction, and while decelerating the swivel base 3 to the position θ _f set by the setting device 22 at a predetermined speed. A circuit for automatically controlling the drive controller 15 to stop the drive controller 15 is built into the control device 19, and repeated turning operations for moving the bucket between the excavation position and the earth and sand discharge position can be easily performed simply by operating the start command using the lever 16. It is configured so that it can be done.

The valve operation structure 17 is configured by the second valve operation structure 17.
As shown in FIG. 3 and FIG. ₃ , the swinging end of the relay arm 23, which can swing freely around the vertical axis P2, and the operating lever 16 are interlocked and connected by a push/pull rod 24, and the longitudinal axis of the relay arm 23 is A balance arm 25 that can freely swing around the vertical axis P ₃ is attached to the intermediate portion of the direction, and a push/pull operation rod 26 for the swing bracket operation valve V ₂ in the multiple valve V is attached to one end of the balance arm 25. The push/pull operation rod 27 of the swing operation valve _V1 is connected to the other end of the balance arm 25 via the interlocking mechanism 17A.

The engaging portion 26 of each operating rod 26, 27
a, 27a to prevent the pushing and pulling movement of the operating rods 26, 27, thereby controlling the operating valves V ₁ , V ₂
The locking tool 28 that fixes the
6a, 27a, and when the swing bracket operation valve _V2 is in the fixed state, the pivot connection point between the balance arm 25 and the swing bracket side operation rod 26 is provided. The lever 16 and the swing operation valve V ₁ are linked to each other by using a fixed fulcrum, and when the swing operation valve V ₁ is in a fixed state, the swing side pivot connection point of the balance arm 25 is used as a fixed fulcrum, The lever 16 and the swing bracket operating valve _V2 are configured to be in an interlocked state.

In other words, one lever 16 is configured to selectively operate either the swivel base 3 or the swing bracket 9.

One end of the linking member 29, which is swingable around the vertical axis _P4 , is interlocked and connected to the swing-side operating rod 27 via a stroke error absorbing spring 30, and a pair of elongated holes 29a, 29b are connected to the linking member 29. , are formed by distributing and arranging them with respect to the swing axis P ₄ , and a pair of linking rods 31 a and 31 b which are pivotally supported at the pivoting connection point on the swinging side of the balance arm 25 are connected to the elongated hole 2 .
9a and 29b are respectively connected by pin engagement. When the balance arm 25 swings to one side, only one of the linking rods 31
a, 31b are pins 32a, 32b and elongated hole 29a,
29b, the linking member 29 is in an interlocking state, and the other linking rod 31b, 31a
However, due to the flexibility of the elongated holes 29b and 29a, the linking member 2
Furthermore, when the balance arm 25 swings to the other side, the elongated holes 29a and 29b are arranged so that the interlocking and non-interlocking states of the linking rods 31a and 31b are reversed. pin 32 against
Set the arrangement of a and 32b, and then turn the lever 16
A mechanical interlocking mechanism 17A is constructed which interlocks and operates the swing operation valve _V1 only in one direction from its neutral position for both forward and reverse swing operations.

Further, the operation state detection device 18 is composed of a differential transformer operatively connected to the push/pull rod 24.

The valve 14 interposed between the operation valve V ₁ in the multiple valve V and the hydraulic motor 5 is replaced by a proportional valve with a function of adjusting the supply oil amount as described above. It may be configured as a simple three-position switching valve that switches between reverse drive and stop; in that case, a variable shutoff valve or the like for controlling the rotational speed of the swivel base 3 is interposed in the forward and return oil passages 13a and 13b. Furthermore, the valve 1
Various improvements can be made to the operating structure of 4, such as using an electromagnetic type instead of a pilot pressure type, and the valves 14 are valves that cut off oil supply to the hydraulic motor 5 when the swivel table automatically stops. From this point of view, these valves are collectively referred to as intermittent valves 14.

The operating valve in the multiple valve V is activated by either forward or reverse operation of the operating tool 16 such as a lever from the stop position N.
Various improvements can be made to the specific structure of the mechanical interlocking mechanism 17A for operating V ₁ in only one direction from the stop (neutral) position.

Further, the specific detection form of the detector 21 that detects the rotation angle θ of the swivel base 3 with respect to the vehicle body, and the detection device 18 that detects the operating direction of the operating tool 16, and
The structure can also be improved in various ways.

The present invention is directed to a swivel type work vehicle for various uses, in which a swivel platform 3 is equipped with various types of work devices 8 such as excavation work devices and cranes.

[Brief explanation of the drawing]

The drawings show an embodiment of the swing-type work vehicle according to the present invention and a conventional example, in which Fig. 1 is an overall side view, Fig. 2 is a schematic operation system diagram, and Fig. 3 shows the - in Fig. 2.
4 is a hydraulic circuit diagram showing a conventional structure. 3...Swivel base, 5...Hydraulic motor, 8...Work device, 12...Center bypass, 14...Intermittent valve, 16...Operation tool, 17A...Mechanical interlocking mechanism, 18...Operation direction detection Device, 19... Control device, 21... Angle detector, 22... Setting device, V...
…Multiple valve, V ₁ …Operation valve, N…Stop position,
θ...Rotation angle, _θf ...Setting versus vehicle body position.

Claims (1)

[Claims] 1 An artificial valve V 1 that can be freely switched between forward and reverse drive and a stop position is connected to the center bypass ₁ for the hydraulic motor 5 that rotates the swivel table 3 equipped with the working device 8.
A detector 21 that is provided in the multiple valve V with 2 and detects the angle θ of the swivel base 3 relative to the vehicle body, and a setting device 2 that sets the position θ _f relative to the vehicle body at which the swivel base 3 should be stopped.
2. A device 18 that detects the operating direction of the operating tool 16 of the human-operated valve V ₁ , a valve 14 that cuts off and on the oil supply to the hydraulic motor 5, and the angle detector 21 and the operating direction detection device 18. Based on the information, the swivel base ₃ is
The swing type work vehicle is provided with a control device 19 that automatically closes the valve 14 so as to automatically stop the valve 14, and the shut-off valve 14 is the manually operated valve.
It consists of one valve of forward/reverse drive and stop operation type placed between V ₁ and the hydraulic motor 5, and between the manually operated valve V ₁ and its operating tool 16, an operating tool 16 is provided.
A rotating work vehicle equipped with a mechanical interlocking mechanism 17A configured to operate the operation valve _V1 in one direction from the stop position by either forward or reverse operation from the stop position N.