JP2573129Y2 - Hydraulic switching device of demolition machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic switching device of a dismantling machine for dismantling a structure equipped with a very long attachment.

[0002]

2. Description of the Related Art FIG. 5 is a side view of a dismantling machine for dismantling structures such as buildings. In the figure, reference numeral 1 denotes a hydraulic excavator body (hereinafter, referred to as hydraulic excavator 1) which is a construction machine;
Is a super long attachment attached to the front part of the excavator 1, 3 is a joint boom of the super long attachment 2, 4 is an int boom, 5 is an arm, 6 is a crushing tool, 7 is a base end side of the joint boom A boom, 8 is a relay boom, 9 is a base end boom, 10 is a boom cylinder of various hydraulic cylinders, 11 is an intub boom cylinder,
Reference numeral 12 denotes an arm cylinder, and reference numeral 13 denotes a bucket cylinder (a hydraulic cylinder for the crushing tool 6 but referred to as a bucket cylinder). FIG. 6 is a rear view of an essential part of the base end side 7 viewed from A in FIG. In the figure, reference numerals 14 and 14 'denote pipes leading to a bottom-side oil chamber of the arm cylinder 12, and 15 denotes a pipe 14
Slow return valves 16-16 ', 16 and 16' are bypass pipes connected in parallel to the slow return valve 15, and 17 is a manual on-off valve provided on bypass pipes 16-16 '. Is a stop valve, 18 is a pipe leading to the rod-side oil chamber of the arm cylinder 12, and 23 and 24 are stop valves, respectively. FIG. 7 is a side view of the hydraulic excavator when the base end boom 7 of the ultra-long attachment 2 is attached and the front part thereof is replaced with the backhoe work attachment 19.
In the figure, 12 'is an arm cylinder, 13' is a bucket cylinder, 20 is a front boom of the backhoe work attachment 19, 21 is an arm, and 22 is a bucket.

FIG. 8 is a hydraulic circuit diagram of a main part of a conventional dismantling machine. In the figure, reference numerals 23 and 24 denote pipes 1 respectively.
4 ', 18 are couplers, 25 is a swing motor, 2
6 is a pilot switching valve for an arm, 27 is a pilot switching valve for a boom, 28 is a pilot switching valve for a bucket, 2
9, 30 are first and second pumps, 31 is a pilot pump, 32 is a hydraulic remote control valve for an arm, 33 and 34 are pilot valves of the hydraulic remote control valve 32, and 35 is a switch for the pilot pressure deriving circuit of the hydraulic remote control valve 32. Pilot pressure switching valve, 36 is a hydraulic remote control valve for boom, 37,
37 is a slow return valve provided on each of the boom cylinders 10 and 10, and 38 and 38 are slow return valves 37 and 3 respectively.
A stop valve connected in parallel to 7;
Reference numeral 9 denotes a slow return valve provided on the bucket cylinder 13, reference numeral 40 denotes a stop valve connected in parallel to the slow return valve 39, reference numeral 41 denotes an oil tank, and reference numerals Ey and Rolo denote pilot line connections. As shown in FIG. 8, the slow return valves 15, 37, 37, and 39 each include a variable throttle (for example, the variable throttle 42 in the slow return valve 15) and a check valve (for example, the check valve 43 in the slow return valve 15). Are connected in parallel. When the joint of the ultra-long attachment 2 is bent and rotated in a predetermined forward direction, various hydraulic cylinders 10 and
Slow return valve 3 for 10, 12, and 13 respectively
7, 37, 15, 39 are arranged.

Next, a conventional hydraulic switching device will be described with reference to FIGS. When the hydraulic excavator performs the dismantling work with the super long attachment 2 mounted, the stop valves 38, 38, 17, 40 are closed, the stop valves 23 and 24 are opened, and the pilot pressure switching valve 3 is opened.
5 is set to the C position. Thus, when the boom cylinder 10, the arm cylinder 12, and the bucket cylinder 13 are operated, the slow return valves 37, 1
5, 39 effect is exhibited, joint boom 3, arm 5,
The longitudinal rotation of the crushing tool 6 can be safely moved at a low operation speed. By operating the operation lever 44 (shown in FIG. 8) of the hydraulic remote control valve 32 for the arm toward the rear position E, the retracting operation of the arm 5 can be performed. When the operation lever 44 is operated from the neutral position to the position direction F, the arm 5 performs the pushing operation.

[0005] Next, when the super long attachment 2 is replaced with a backhoe work attachment 19 (hereinafter referred to as a backhoe attachment 19) and the excavator performs excavation work, the stop valves 38, 17,
With all 40 open, slow return valves 37, 1
5, 39 do not become resistance of pressure oil supply and discharge. Also, the arm cylinder 12 'of the backhoe attachment 19
Is mounted on the back side of the front boom 20, the arm cylinder 12 'must be extended when the arm is retracted. That is, the arm cylinder 12 of the ultra-long attachment 2 is provided on the abdominal surface of the arm 5, and the arm cylinder 12
Is the reverse of the case where is operated to reduce. The driver is accustomed to moving the operation lever 44 of the arm remote control valve 32 into the arm position in the direction of the position E, and switches the pilot pressure switching valve 35 to the position D from the viewpoint of safety. Thereby, the operation direction of the operation lever 44 in the arm retracting operation of the backhoe attachment 19 can be made the same direction as when the super long attachment 2 is attached.

[0006]

Since the arm cylinder in the ultra-long attachment is mounted on the abdominal surface of the arm, the arm cylinder must be reduced when the arm is retracted. However, when the arm cylinder is replaced with the backhoe attachment, the arm cylinder is attached to the rear side of the front boom, so that the arm cylinder must be extended when the arm retracting operation is performed. Since the above arm cylinder is commercially available from the economic point of view, and it is difficult to change the pipe connection relationship when the attachment is replaced, the pilot pressure switching valve is provided on the body of the hydraulic shovel, and the arm hydraulic pressure is used. By switching the pilot pressure derivation circuit of the remote control valve, the operating direction of the arm of the operating lever is set to be the same. Therefore, when replacing the super long attachment and the backhoe attachment, it is necessary to open and close the stop valve provided on the base end boom and switch the pilot pressure switching valve provided on the vehicle body. It was troublesome. Also, the cost of installing the pilot pressure switching valve was considerably high. An object of the present invention is to provide a hydraulic switching device that can solve the above-mentioned problems.

[0007]

According to the hydraulic switching device of the present invention, a three-way which can be manually operated to the pressure oil supply line and the return oil line when the arm cylinder mounted on the arm ventral side of the super long attachment is contracted. A return-side three-way switching valve provided in the return oil line with two switching valves connected to the bottom-side oil chamber of the arm cylinder and the slow return valve respectively, and the remaining Is connected to the upstream line of the supply-side three-way switching valve provided in the pressure oil supply line, and the supply-side three-way switching valve provided in the pressure oil supply line is one of the three-way ports. Two ports are connected to the rod-side oil chamber of the arm cylinder and the pressure oil supply upstream pipe, respectively, and the other port is connected to the return oil discharge downstream pipe of the slow return valve. , When the arm of the long attachment is operated, the switching operation of the two three-way switching valves prevents the pressure oil supply line and the return oil line from communicating with each other, and when the super long attachment is replaced with the backhoe attachment, two pieces are attached. The supply pressure oil is supplied to the bottom-side oil chamber of the arm cylinder through the return-side three-way switching valve by the switching operation of the three-way switching valve, and the return oil from the rod-side oil chamber is discharged through the supply-side three-way switching valve. It was to so.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a hydraulic circuit diagram of a main part of a dismantling machine having a hydraulic switching device according to the present invention. In the drawings, the same reference numerals are given to components using the same components as the conventional technology. 7 'is a base end boom, 45 and 46 are three-way switching valves, P1, P2, and P3 are three-way ports of the three-way switching valve 45, and Q1, Q2, and Q3 are three-way ports of the three-way switching valve 46, respectively. , 47 and 48 are supply / discharge interconnection pipes, respectively. FIG. 2 is a rear view of a main part of the proximal end boom 7 'in FIG. In the figure, 49 and 50 are T-shaped connection fittings, respectively. FIG. 3 shows the super long attachment 2 shown in FIG.
9 is a main part hydraulic circuit diagram showing a case where the mounting is changed to 9; FIG.
FIG. 4 is a main part hydraulic circuit diagram showing a state in which the ultra-long attachment 2 or the backhoe attachment 19 is completely removed and only the base end boom 7 'commonly used is mounted.

Next, the configuration of the hydraulic switching device of the present invention is shown in FIG.
4 will be described. In the present invention, the arm cylinder 1 attached to the arm 5 on the ventral side of the super long attachment 2
The two-way switching valves 46 and 45, which can be manually operated, are respectively interposed between the pressure oil supply line and the return oil line when the pressure reducing valve 2 is operated to be reduced, and the three-way switching valve 45 provided on the return oil line is connected to the three-way port. Two of the ports P1 and P2 are connected to the bottom side oil chamber 51 of the arm cylinder 12 and the slow return valve 15, respectively, and the other port P3 is connected to the supply / discharge interconnection pipe 47 via the three-way switching valve. The three-way switching valve 46 connected to the upstream (supply-side) pipeline 52-53 of the pressure oil supply pipeline is connected to two ports Q1 and Q2 of the three ports by arm cylinders, respectively. 1
2 is connected to the rod-side oil chamber 54 and the pressure oil supply upstream pipe 53, and the other one port Q3 is connected to the return oil discharge downstream pipe of the slow return valve 15 via the supply / discharge interconnection pipe 48. It was connected to roads 55-56.

Next, the operation of the hydraulic switching device according to the present invention will be described. First, as a first case, a case where the dismantling operation is performed with the super long attachment 2 attached will be described with reference to FIG. Stop valve 3 provided on base end boom 7 '
8, 38 and 40 are closed as in the prior art. Stop valves a and b (shown by broken lines) provided in supply / discharge pipes leading to the bucket cylinder 13 are closed in order to prevent oil from flowing out when the pipes are cut off. 13 is left open when used. The three-way switching valve 46 switches so that the ports Q2 and Q1 are opened and the port Q3 is shut off, and the three-way switching valve 45 switches so that the ports P1 and P2 are opened and the port P3 is shut off. Keep it. Therefore, the operation lever 44 of the hydraulic remote control valve 32 is operated in the direction of the position E from the neutral position. The pilot pressure from the pilot pump 31 is applied to the pilot valve 34 and the pilot line 57.
, And acts on the pilot pressure receiving portion 58. Since the arm pilot switching valve 26 is switched to the G position, the pressure oil from the second pump 30 passes through the G position of the pilot switching valve 26, the pipes 52 and 53, the three-way switching valve 46, and the pipe 59, and The oil is supplied to the rod-side oil chamber 54 of the cylinder 12. At the same time, the return oil from the bottom side oil chamber 51 passes through the pipeline 60, the three-way switching valve 45, the pipeline 61, the slow return valve 15, the pipelines 55 and 56, and the pilot switching valve 26 to the oil tank 41. Is discharged. Thereby, the effect of the slow return valve 15 is exhibited, and the retraction operation of the arm 5 can be performed safely.

Next, as a second case, a case where the super long attachment 2 is detached and replaced with the backhoe attachment 19 to perform excavation will be described with reference to FIG. Stop valve 3 provided on base end boom 7 '
8, 38 and 40 are left open as in the prior art. The three-way switching valve 45 switches so that the ports P3 and P1 are opened and the port P2 is shut off, and the three-way switching valve 46 switches so that the ports Q1 and Q3 are opened and the port Q2 is shut off. deep. Therefore, the operation lever 44 of the hydraulic remote control valve 32 is operated in the direction of the position E from the neutral position. The pilot pressure from the pilot pump 31 acts on the pilot pressure receiving portion 58 via the pilot valve 34 and the pilot line 57. Since the arm pilot switching valve 26 is switched to the G position, the pressure oil from the second pump 30 is supplied to the G position of the pilot switching valve 26, the pipelines 52, 4
The oil is supplied to the rod-side oil chamber 54 'of the arm cylinder 12' via the two- and three-way switching valve 45 and the pipeline 62. At the same time, the return oil from the bottom oil chamber 51 'is discharged to the oil tank 41 via the pipe 63, the three-way switching valve 46, the pipes 48 and 56, and the pilot switching valve 26 at the G position. Thereby, the expansion and contraction operation speed of the arm cylinder 12 ′ can be increased without being affected by the slow return valve 15, and a troublesome excavation operation can be performed.

FIG. 4 shows a third case in which the ultra-long attachment 2 or the backhoe attachment 19 is completely removed and only the base end boom 7 'commonly used is attached. In this case, neither demolition work nor excavation work is performed, so the stop valve 38,
Although the operations of 38 and 40 are unnecessary, the stop valves a and b provided on the bucket operation circuit side are closed to prevent oil outflow. The three-way switching valve 45 switches so that the ports P2 and P3 are opened and the port P1 is shut off, and the three-way switching valve 46 switches so that the ports Q2 and Q3 are opened and the port Q1 is shut off. Keep it. Since the ports P1 and Q1 of the three-way switching valves 45 and 46 are closed, oil inside the pilot switching valve 26 does not flow out. That is, it is economical because the stop valves 23 and 24 (shown in FIG. 8) provided in the conventional hydraulic circuit can be dispensed with. In addition, even if the arm hydraulic remote control valve 32 is operated casually in the third case, the oil discharged from the second pump 30 is not supplied to the pilot switching valve 2.
6. Since it only returns to the oil tank 41 via the three-way switching valve 45 or 46, an unsafe state does not occur.

[0013]

The arm cylinder in the ultra-long attachment is attached to the abdominal surface of the arm, and the arm cylinder in the backhoe attachment is attached to the back of the front boom. Therefore, when performing the replacement operation of the super long attachment to the backhoe attachment, the pipe connection relationship of the arm cylinder had to be changed in order to make the arm retraction operation direction of the operation lever for hydraulic remote control valve the same direction. At the time of replacement, the above change is difficult due to the structure of the piping.
could not. Inevitably, a pilot pressure switching valve is previously provided on the vehicle body to switch the pilot pressure derivation circuit of the hydraulic remote control valve. Therefore, when replacing the super long attachment and the backhoe attachment, it is necessary to open and close the stop valve provided on the base end boom and switch the pilot pressure switching valve provided on the vehicle body. It was troublesome. Also, the cost of installing the pilot pressure switching valve was considerably high. However, in the hydraulic switching device of the present invention, a manually operable three-way switching valve is interposed in the pressure oil supply line and the return oil line when the arm cylinder attached to the arm ventral side of the super long attachment is to be reduced in size, The return three-way switching valve provided in the return oil line connects two of the three ports to the bottom oil chamber of the arm cylinder and the slow return valve, respectively, and supplies the remaining one port with pressure oil. The supply-side three-way switching valve connected to the upstream side of the supply-side three-way switching valve provided in the pipeline and the supply-side three-way switching valve provided in the pressure oil supply pipeline connects two of the three ports to the arm cylinder, respectively. And the other port is connected to the return oil discharge downstream pipe of the slow return valve, and the extra long attachment is connected. When the arm is operated, the pressure oil supply line and the return oil line are prevented from communicating with each other by switching operation of the two three-way switching valves, and two three-way switching is performed when the super long attachment is replaced with the backhoe attachment. By the switching operation of the valve, the supply pressure oil is supplied to the bottom oil chamber of the arm cylinder via the return side three-way switching valve, and the return oil from the rod side oil chamber is discharged via the supply side three-way switching valve. did. Accordingly, when the attachments are replaced, the operation of switching the hydraulic pressure of the pipes may be performed on the stop valve and the three-way switching valve that are arranged centrally on the base end boom, so that the operation can be easily performed. it can. Also, a pilot pressure switching valve used in the hydraulic switching device of the prior art, a stop valve juxtaposed to a slow return valve in the arm cylinder return oil line, and a stop valve interposed in the arm cylinder supply / discharge line. Can be eliminated, so that it can be manufactured at a lower cost than the conventional hydraulic piping apparatus manufacturing cost. Therefore, in the dismantling machine equipped with the hydraulic switching device of the present invention, the work of replacing the super long attachment and the backhoe attachment can be performed easily and in a short time, and the hydraulic switching device can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a main part hydraulic circuit diagram of a dismantling machine having a hydraulic switching device of the present invention.

FIG. 2 is a rear view of a main part of the proximal end boom in FIG.

3 is a main part hydraulic circuit diagram showing a case where the super long attachment in FIG. 1 is replaced with a backhoe attachment.

FIG. 4 is a hydraulic circuit diagram of the main part of the present invention, showing a state in which the attachment is completely removed and only the base end boom used for common mounting is mounted.

FIG. 5 is a side view of the dismantling machine.

6 is a main part rear view of the base end boom viewed from A in FIG. 5;

FIG. 7 is a side view of the hydraulic excavator when a work attachment for a backhoe is attached.

FIG. 8 is a hydraulic circuit diagram of a main part of a conventional dismantling machine.

[Explanation of symbols]

2 Super long attachment 5, 21 Arm 7, 7 'Base end boom 10 Boom cylinder 12, 12' Arm cylinder 13, 13 'Bucket cylinder 15, 37, 39 Slow return valve 17, 23, 24, 38, 40, a , B Stop valve 19 Backhoe work attachment 26, 27, 28 Pilot switching valve 32, 36 Hydraulic remote controller 35 Pilot pressure switching valve 44 Operating lever 45, 46 Three-way switching valve 47, 48 (for supply / discharge interconnection) piping

Claims (1)

(57) [Scope of request for utility model registration] 1. A connecting part boom, an intub boom, an arm, and a crushing tool are sequentially connected to a front part of a construction machine to form a super long attachment, and the operating speed of various hydraulic cylinders for bending and rotating the super long attachment is reduced. In order to do this, each hydraulic cylinder circuit is provided with a slow return valve equipped with a throttle and a check valve, all of the slow return valves are arranged on the base end boom of the joint boom, and in parallel with the slow return valve, Connect the bypass pipe with an on-off valve, and when the dismantling machine performs the dismantling work with the ultra-long attachment, close the on-off valve, and the dismantling machine replaces the ultra-long attachment with the backhoe attachment. In a hydraulic switching device in which the on-off valve is opened when performing excavation work, When the arm cylinder attached to the arm attachment side of the long attachment is to be reduced in size, a manually operable three-way switching valve is interposed between the pressure oil supply line and the return oil line, and the return-side three-way switch is provided on the return oil line. The valve connects two of the three ports to the bottom oil chamber of the arm cylinder and the slow return valve, respectively, and the other port is a supply-side three-way switching valve provided in the pressure oil supply line. To the upstream pipeline of
The supply-side three-way switching valve provided in the pressure oil supply line connects two of the three ports to the rod-side oil chamber of the arm cylinder and the pressure oil supply upstream line, respectively.
The remaining one port is connected to the return oil discharge downstream line of the slow return valve, and when the arm of the super long attachment is operated, the pressure oil supply line is connected to the pressure oil supply line by switching the two three-way switching valves. and return oil pipe line is to not understand each other, the ultra-long attachment backhoe
When the attachment is replaced, the supply pressure oil is supplied to the bottom oil chamber of the arm cylinder via the return side three-way switching valve by the switching operation of the two three-way switching valves, and the return oil from the rod side oil chamber is supplied to the supply side. A hydraulic switching device for a demolition machine, wherein the hydraulic pressure is discharged through a three-way switching valve.