JPH0711670A - Hydraulic drive device for construction civil engineering machine - Google Patents

Abstract

PURPOSE:To perform control of an extension hydraulic actuator by means of an existing operation lever by a method wherein solenoid valves in respective first and second valve blocks are switched by means of a press button switch arranged to a multiple switching valve. CONSTITUTION:A second valve block 32 located between a first valve block 24 and a revolving motor 16, and an opening closing cylinder 17 is disposed between a second block 32 and an opening closing cylinder 17 of a primary piping 25 of a third primary piping 25. A hydraulic drive device for a construction civil engineering machine comprises a third solenoid valve 34 connected to the forward rotation side of the revolving motor 16 through a fourth primary piping 33; and a solenoid valve 36 disposed between an opening closing cylinder 17 of a third secondary piping 27 and a second solenoid valve 28 is connected to the reversing side of the revolving motor 16 through a fourth secondary piping 35. By switching the solenoid valves 26 and 28 of the first and second valve blocks 24 and 32 by means of press button swithes 42 and 44, the hydraulic circuits of two actuators of existing and extension actuators are switched by means of the first valve block 24 and the extension hydraulic actuator is controlled by means of the second valve block 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic drive system for a construction civil engineering machine such as a power shovel used for construction civil engineering.

[0002]

2. Description of the Related Art For example, as a construction civil engineering machine for excavating work in construction civil engineering, a power shovel is used which operates hydraulic actuators of respective working parts by pressure oil generated from a hydraulic pump directly connected to an engine. The power shovel will be described with reference to FIG.

In FIG. 2, (1) is a main body of a power shovel, in which a cab (3) is rotatably installed on a crawler (2) and a slewing motor (4) arranged on the crawler (2) is installed. The cab (3) is rotated 360 ° with respect to the crawler (2). (5) is a boom in which the base end portion is attached to the cab (3) of the power shovel body (1) so that the base end portion can be undulated, and the boom and cavities (6) are arranged between the boom and the cab (3). The cab (3) moves up and down. Reference numeral (7) denotes an arm having a base end portion swingably attached to a tip end portion of the boom (5), and an arm cylinder (8) arranged between the arm end and the boom (5). ). Reference numeral (9) is a shovel attached to the tip of the arm (7), and an excavating cylinder (11) is provided between the excavator and the arm (7) via a link mechanism (10). ) To swing.

In the above-mentioned structure, the swing motor (4), the hoisting cylinder (6), the arm cylinder (8) and the excavating cylinder (11) are operated to operate the cab (3) of the power shovel body (1). The excavation work at the destination can be freely performed by performing the turning motion, the hoisting motion of the boom (5), the swing motion of the arm (7), and the swing motion of the shovel (9).

By the way, in the above power shovel, the shovel (9) attached to the tip of the arm (7).
By exchanging with various attachments as required, work other than excavation work is possible. For example, in FIG.
As shown in FIG. 6, by exchanging with the grip hand (12), it is possible to carry out digging work.

In the grip hand (12), a swingable support frame (13) is attached to the tip of the arm (7) by an excavating cylinder (11) via a link mechanism (10). The main grip (14) is rotatably supported by the main grip (14), and the auxiliary grip (15) is openably and closably attached to the main grip (14) to support the support frame (1
The main grip (1
By pivoting 4) with respect to the support frame (13), the main grip (14) and the sub-grip (15) are secured in the optimum position and angle for the engaging work, and both grips (14) (15) are secured. ) A sub-grip (15) is opened / closed with respect to the main grip (14) by an opening / closing cylinder (17) arranged between the two grips (14) and (15) so that an object to be digged can be caught. Has been done.

[0007]

In the power shovel, when the clip hand (12) is attached to the tip of the arm (7) to carry out digging work, the grip hand (12) has a hydraulic actuator. Since the swing motor (16) and the opening / closing cylinder (17) are arranged, the hydraulic system for controlling the swing motor (16) and the opening / closing cylinder (17) is added to the existing hydraulic system of the power shovel. There is a need. In this way, when the hydraulic system for controlling the hydraulic actuator of the grip hand (12) is added to the existing hydraulic system of the power shovel, in addition to the existing four operation levers of the power shovel, the grip hand ( Two operation levers for controlling the hydraulic actuator of 12) will be added, and such an addition of the operation lever will lead to an operation of changing the holding of the operation lever by the operator. There was a problem that required.

Further, the power shovel requires a large amount of oil to be supplied to the existing excavating cylinder (11), whereas the added grip hand (12) has a swing motor (16) and an opening / closing cylinder. It is necessary to limit the amount of oil supplied to (17), but the swing motor (16) and opening / closing cylinder (17) of the grip hand (12) do not affect the amount of oil supplied to the existing drilling cylinder (11). It is difficult to limit the amount of oil supplied to. For this reason, when the gripping speed of the grip hand (12) becomes too fast and the soft material is gripped, the gripping hand is crushed or the speed of the excavating cylinder (11) is reduced, resulting in poor workability. There's a problem.

The present invention has been proposed in view of the above-mentioned problems, and an object of the present invention is to enable control of an added hydraulic actuator with an existing operation lever, and An object of the present invention is to provide a hydraulic drive system for a construction civil engineering machine that can limit the amount of oil supplied to an added hydraulic actuator without affecting the amount of oil supplied.

[0010]

In order to achieve the above object, the present invention provides a construction civil engineering machine for supplying hydraulic oil generated from a hydraulic pump directly connected to an engine to a hydraulic actuator of each working portion through a main switching valve. In the hydraulic drive system according to the first aspect, a solenoid valve is used to switch the hydraulic circuits of the existing hydraulic actuator and the added hydraulic actuator between the existing hydraulic actuator and the multiple switching valve for controlling the same. A valve block is provided, and a second valve block for controlling the added hydraulic actuator by an electromagnetic valve is provided between the added hydraulic actuator and the first valve block, and the multiple switching is performed. A push button switch for switching the solenoid valves of the first and second valve blocks is provided on the valve operating lever. Those digits.

[0011]

According to the present invention, by switching the solenoid valves of the first and second valve blocks by the push button switch provided in the multiplex switching valve, the hydraulic pressure of the existing hydraulic actuator and the hydraulic actuator of the additional hydraulic actuator are changed. The circuit switching is performed by the first valve block, and the added hydraulic actuator is controlled by the second valve block. As a result, it is possible to control the added hydraulic actuator with the existing operation lever, and it is possible to limit the amount of oil supplied to the added hydraulic actuator without affecting the amount of oil supplied to the existing hydraulic actuator.

[0012]

EXAMPLE An example in which the hydraulic drive system for a construction civil engineering machine according to the present invention is applied to a case where a grip hand (12) is attached as an attachment to a tip end portion of an arm (7) of a power shovel based on FIG. Explain. Note that FIG. 1 is a hydraulic circuit diagram showing only the hydraulic system of the main part thereof, and the same members as those in FIG. 3 of the conventional description are designated by the same reference numerals, and the description of the overlapping matters will be omitted.

In FIG. 1, (18) is a drilling cylinder (1
1) A first multiple switching valve for controlling
It is connected to the head side of the excavation cylinder (11) via the primary pipe (19) and is connected to the rod side of the excavation cylinder (11) via the first secondary pipe (20).
(21) is a second multiple switching valve for controlling an arm cylinder (not shown), which is connected to the head side of the arm cylinder via a second primary pipe (22), and
It is connected to the rod side of the arm cylinder via the second secondary pipe (23).

Reference numeral (24) is a first valve block for switching the hydraulic circuits of the excavating cylinder (11), the swing motor (16) and the opening / closing cylinder (17), and the first multiple switching valve (18) and the excavating cylinder. It is attached to the base of the excavation cylinder (11) so as to be placed between (1) and (11). This first
The valve block (24) of the first solenoid valve (24) disposed in the middle of the third primary pipe (25) connecting the first primary pipe (19) and the head side of the opening / closing cylinder (17). 26) and a second solenoid valve (28) arranged in the middle of a third secondary pipe (27) connecting the first secondary pipe (20) and the rod side of the opening / closing cylinder (17). And a first pilot check valve (29) and a second pilot check valve (29) arranged on the side of the excavating cylinder (11) with respect to the connection portion between the first primary pipe (19) and the third primary pipe (25).
Pilot check valve (30) and the first secondary piping (2
0) and a third pilot check valve (31) arranged on the side of the excavation cylinder (11) with respect to the connection portion with the third secondary pipe (27), and the first and second solenoid valves ( 26) (28)
And first to third pilot check valves (29) (30)
(31) means that when the solenoids on the a side of the first and second solenoid valves (26) and (28) are excited to switch to the parallel position,
Through so that the third pilot check valves (29) (30) (31) are closed, and the solenoids on the b side of the first and second solenoid valves (26) (28) are excited. When switched to the intersecting position, the first to third pilot check valves (29), (30) and (31) are connected so as to be opened.

Reference numeral (32) is a second valve block for controlling the swing motor (16) and the opening / closing cylinder (17), and includes a first valve block (24), a swing motor (16) and an opening / closing cylinder (17). It is attached to the grip hand (12) shown in FIG. The second valve block (32) is arranged between the opening / closing cylinder (17) of the third primary pipe (25) and the first solenoid valve (26), and the swing motor (16) is normally swung. The third solenoid valve (34) connected to the side through the fourth primary pipe (33) and the third secondary pipe (2
It is arranged between the opening / closing cylinder (17) of 7) and the second solenoid valve (28), and is connected to the reverse turning side of the turning motor (16) through the fourth secondary pipe (35). It is composed of a fourth solenoid valve (36).

Reference numeral (37) is a hydraulic pressure source for generating pressure oil by a hydraulic pump directly connected to an engine (not shown), and a tank (3
8) is connected via a pipe (39), a second multiple switching valve (21), a first multiple switching valve (18) and a pipe (40). The second multiple switching valve (21) and the first multiple switching valve (18) are connected inside the valve.

Reference numeral (41) is a first operating lever for switching the first multiple switching valve (18), and a first push button switch (42) is provided on the top thereof. The first push button switch (42) includes a b-side solenoid of the first solenoid valve (26) and the second solenoid valve (28) and a third solenoid valve (3).
4) and the solenoid on the a side of the fourth solenoid valve (36) are electrically connected to each other, and the first push button switch (4
When 2) is pressed, the first solenoid valve (26) and the second solenoid valve (2
The b-side solenoid of 8) and the a-side solenoids of the third solenoid valve (34) and the fourth solenoid valve (36) are excited.

(43) is a second operating lever for switching the second multiple switching valve (21), and a second push button switch (44) is provided on the top thereof. The second push button switch (44) includes a b-side solenoid of the first solenoid valve (26) and the second solenoid valve (28) and a third solenoid valve (3
4) and the solenoid on the b side of the fourth solenoid valve (36) are electrically connected to the second push button switch (4
When 4) is pressed, the first solenoid valve (26) and the second solenoid valve (2
The b-side solenoid of 8) and the b-side solenoids of the third solenoid valve (34) and the fourth solenoid valve (36) are excited. Incidentally, when the first and second push button switches (42, 44) are not pressed, the a-side solenoids of the first solenoid valve (26) and the second solenoid valve (28) are excited.

(45) is a first throttle valve provided immediately before the first solenoid valve (26) of the third primary pipe (25), and (46) is a third secondary pipe (27). It is a second throttle valve provided immediately before the second solenoid valve (28).

Next, the operation procedure of the device of the present invention having the above construction will be described.

First, when the excavation cylinder (11) is expanded and contracted to swing the grip hand (12), the first operation is performed without pressing the first and second push button switches (42) (44). The first multiple switching valve (18) is switched by the lever (41). That is, if the first and second push button switches (42) (44) are not pressed, the a-side solenoids of the first and second solenoid valves (26) (28) are excited and the first to second solenoids are excited.
The third pilot check valves (29) to (31) are opened, and a hydraulic circuit to the excavation cylinder (11) is configured. In this state, the first operation lever (41)
Of the first primary switching valve (18) after the pressure oil from the hydraulic source (37) has passed through the first multiple switching valve (18) by switching the multiple switching valve (18) from the shut-off position to the parallel position or the crossing position. Piping (19) or first secondary piping (2
It is supplied to the head side or the rod side of the excavation cylinder (11) through 0), and the excavation cylinder (11) can be expanded and contracted.

Next, when the opening / closing cylinder (17) is expanded / contracted to open / close the clip hand (12), the second push button switch (44) provided on the top of the second operation lever (43). By pressing, the b-side solenoids of the first solenoid valve (26) and the second solenoid valve (28) are excited to close the first to third pilot check valves (29) to (31). At the same time, the b-side solenoids of the third solenoid valve (34) and the fourth solenoid valve (36) are excited to bring the third solenoid valve (34) and the fourth solenoid valve (36) into the state. The hydraulic circuit to the open / close cylinder (17) is configured by switching from the shutoff position to the parallel position. In this state, by pressing the second push button switch (44) and switching the first multiple switching valve (18) from the shut-off position to the parallel position or the cross position by the first operating lever (41), the hydraulic pressure is changed. After the pressure oil from the source (37) has passed through the first multiple switching valve (18), the first primary pipe (19) and the third primary pipe (25), or the first secondary pipe (20). ) And the third secondary pipe (27) to be supplied to the head side or the rod side of the opening / closing cylinder (17), and the opening / closing cylinder (17) can be expanded and contracted. At this time, the amount of oil supplied to the opening / closing cylinder (17) can be limited by the first throttle valve (45) and the second throttle valve (46). Therefore, when the valve openings of the first throttle valve (45) and the second throttle valve (46) are adjusted, the grip hand (12)
You can adjust the digging speed of, and you can dig in the optimum condition.

By the way, when the opening / closing cylinder (17) is retracted, pressure oil flows from the pilot check valve (31) to the rod side of the excavation cylinder (11).
Since the pressure oil on the head side of 1) is blocked by the pilot check valve (30), the excavation cylinder (11) does not operate.

Next, when the turning motor (16) is turned to turn the clip hand (12),
By pushing the first push button switch (42) provided on the top of the operation lever (41) of the above, the solenoids on the b side of the first solenoid valve (26) and the second solenoid valve (28) are excited. The first to third pilot check valves (29) to (31) are closed, and at the same time, the a-side solenoids of the third solenoid valve (34) and the fourth solenoid valve (36) are excited. The third solenoid valve (34) and the fourth solenoid valve (36) are switched from the shutoff position to the crossing position to form a hydraulic circuit to the swing motor (16). In this state, by pressing the first push button switch (42) and switching the first multiple switching valve (18) from the shut-off position to the parallel position or the cross position by the first operating lever (41), the hydraulic pressure is changed. After the pressure oil from the source (37) passes through the first multiple switching valve (18), the first primary pipe (19), the third primary pipe (25) and the fourth primary pipe (3
3), or the first secondary pipe (20) and the third secondary pipe (2
7) and the fourth secondary pipe (35) through the swing motor (1
It is supplied to the forward turning side or the reverse turning side of 6), and the turning motor (16) can be turned. At this time, the amount of oil supplied to the turning motor (16) can be limited by the first throttle valve (45) and the second throttle valve (46). Therefore, by adjusting the valve openings of the first throttle valve (45) and the second throttle valve (46), the swing speed of the swing motor (16) can be adjusted, and the grip hand (12) can be optimized. You can turn at speed.

By the way, when the turning motor (16) is turned in the reverse direction, pressure oil is introduced from the pilot check valve (31) to the rod side of the excavation cylinder (11).
Since the pressure oil on the head side of 1) is blocked by the pilot check valve (30), the excavation cylinder (11) does not operate.

According to the device of the present invention, by pushing the first and second push button switches (42) (44) provided on the first and second operation levers (41) (43), the excavating cylinder (11) is pushed. )
Since it is possible to switch the hydraulic circuit between the swing motor (26) of the grip hand (12) and the opening / closing cylinder (17), it is not necessary to add an operating lever. For this reason, the operator does not have to change the operation lever, and can familiarize himself with the operation in a short time.

The amount of oil supplied to the turning motor (16) and the opening / closing cylinder (17) of the grip hand (12) is set to the first value.
And because it is limited by the second throttle valve (45) (46),
The amount of oil supplied to the swing motor (16) and the opening / closing cylinder (17) of the grip hand (12) can be limited without affecting the amount of supply to the excavation cylinder (11). For this reason, it is possible to match the gripping speed of the grip hand (12) with the condition of the object to be dipped without sacrificing workability.

Although the above embodiment has described the case where the grip hand (12) is attached as an attachment, the present invention is not limited to this, and a hydraulic actuator other than the grip hand (12) is provided. It can also be applied to attachments and can be widely applied to construction civil engineering machines.

[0029]

According to the present invention, since the operation of the added hydraulic actuator can be performed by the existing operation lever, the operator does not need to change the operation lever, and the operation can be accomplished in a short time. The remarkable effect is shown in the improvement of.

Further, since it is possible to limit the amount of oil supplied to the added hydraulic actuator without affecting the amount of oil supplied to the existing hydraulic actuator, even for a power shovel having a large amount of oil supplied to the excavating cylinder, for example. , Various attachments can be equipped without deteriorating the workability.

By installing the first and second valve blocks on the main body side tip portion and the attachment, respectively, the hydraulic piping can be connected very easily and the attachment can be easily replaced.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit showing only a main part of a hydraulic system of an embodiment in which a hydraulic drive system for a construction civil engineering machine according to the present invention is applied when a grip hand is attached as a tip tool to an arm tip of a power shovel. It is a figure.

FIG. 2 is a schematic view of a power shovel.

FIG. 3 is a schematic diagram of a power shovel in which a grip hand is attached to a tip of an arm.

[Explanation of symbols]

 11 Drilling cylinder 12 Grip hand 16 Swing motor 17 Opening / closing cylinder 18 First multiple switching valve 19 First primary pipe 20 First secondary pipe 24 First valve block 25 Third primary pipe 26 First solenoid valve 27 3rd secondary piping 28 2nd solenoid valve 29 1st pilot check valve 30 2nd pilot check valve 31 3rd pilot check valve 32 2nd valve block 33 4th primary piping 34 3rd Solenoid valve 35 Fourth secondary piping 36 Fourth solenoid valve 37 Hydraulic source 38 Tank 41 First operating lever 42 First push button switch 43 Second operating lever 44 Second push button switch 45 First throttle valve 46 Second throttle valve

Claims (1)

[Claims] 1. A hydraulic drive system for a construction civil engineering machine, wherein hydraulic oil generated from a hydraulic pump directly connected to an engine is supplied to a hydraulic actuator of each working portion through a main switching valve, wherein the existing hydraulic actuator and the existing hydraulic actuator are controlled. A first valve block for switching the hydraulic circuits of the existing hydraulic actuator and the added hydraulic actuator by a solenoid valve is provided between the multiple switching valve and A second valve block that controls the added hydraulic actuator by a solenoid valve is provided between the first valve block and the first and second operation levers of the multiple switching valve.
Is provided with a push button switch for switching the solenoid valve of the valve block of FIG.