JPS6119392B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a striking device in which a piston moves forward to strike an object to be struck, such as concrete, piles, or rivets.

Conventional striking devices, such as those powered by air pressure, generate noise due to exhaust gas and are inefficient. Also, those that use springs or cams are not durable or efficient. In addition, in the case where the piston is reciprocated by hydraulic pressure, the oil passage switching valve is installed in a separate part from the cylinder, which complicates the structure and oil passage and causes problems such as unstable piston operation. Ta.

The present invention addresses the above problems and includes high pressure ports 9, 10, low pressure ports 11, high pressure ports 12,
13 are provided in the cylinder 1 in that order, and the same high pressure ports 13 and 9 are connected to pressure oil supply oil passages 20, 19, and 1.
8 and 15 to the pressure oil inlet 14, and the high pressure port 12 to the high pressure port 10 via the communication passage 21.
Then, the low pressure port 11 is connected to the return oil outlet 23 via the return oil passage 24, and the high pressure port 12,
13, the piston 8 simultaneously closes the low pressure port 11, and immediately before moving forward to strike the object to be struck, the piston 8 cuts off communication between the high pressure ports 12 and 13 and simultaneously opens the low pressure port 11, and the piston 8 moves back. After the low pressure port 11 is closed, it is moved back by the same piston 8 and the high pressure ports 9 and 1 are closed.
At the same time as cutting off the communication between A valve 5 is inserted in series into the cylinder 1 to connect the high pressure ports 9 and 10 and simultaneously close the high pressure port 10 to the forward rear pressure receiving surface 8a of the piston 8. In a hydraulic impact device that is always open on the intermediate pressure receiving surface 8b for the backward movement of the piston 8, the valve 5 is moved backward by the piston 8 to cut off communication between the high pressures 9 and 10, and at the same time the high pressure port 10 is opened to the forward movement of the piston 8. Communication passages 71, 7 that connect the high pressure ports 13, 10 when opened to the rear pressure receiving surface 8a
The hydraulic impact device is characterized by having the piston 2 and 73 provided in the piston 8, and its purpose is to simplify the oil passage and structure, reduce failures, and reduce manufacturing costs. Another object of the present invention is to provide an improved hydraulic striking device that can improve striking force and energy efficiency.

The hydraulic impact device of the present invention is configured as described above, and the piston 8 hits the object to be hit, and the pressure oil 14, 15, 18, 19, 9, 10, 21, 1
2 to the intermediate pressure receiving surface 8b for backward movement of the piston 8, and when the piston 8 starts to move backward, the high pressure ports 12 and 13 are switched to communication, the low pressure port 11 is switched to close, and the pressure oil is switched to 18, 20, It is also sent from 13 and 12 to the intermediate pressure receiving surface 8b for backward movement of the piston 8,
The piston 8 continues to retreat while being accelerated, and the valve 5 also begins to retreat from the middle of the movement. When the piston 8 finishes its retreat, the valve 5 also finishes its retreat, and the high pressure ports 9 and 10 are closed, and the high pressure port 10 is closed. is switched to open with respect to the forward rear pressure receiving surface 8a of the piston 8, and the pressure oil is changed to 14, 15, 18, 20, 13,
12, 21, and 10 to the forward movement rear pressure receiving surface 8a of the piston 8. At this time, the high pressure ports 13 and 10 are communicated through communication passages 71, 72, and 73, and pressure oil is also supplied to the forward movement rear pressure receiving surface 8a of the piston 8 from the communication passages 71, 72, and 73, and the piston 8 is accelerated. When you start moving forward while being hit, and move forward until just before hitting the object, high pressure port 1
2 and 13 are switched to cutoff, the low pressure port 11 is switched to open, the valve 5 is advanced by the accumulator 16, the high pressure ports 9 and 10 are switched to the cutoff, and the high pressure port 10 is switched to the forward rear pressure receiving surface 8a of the piston 8. The pressure oil is switched to 14, 15, 1.
Piston 8 from 8, 19, 9, 10, 21, 12
However, the piston 8 moves forward due to inertia and strikes the object to be struck.

In this way, the hydraulic impact device of the present invention moves forward and backward to connect the low pressure port 11 and the high pressure ports 12, 13, 1.
The striking piston 8, which switches between 0 and 13, and the valve 5, which switches the high pressure ports 9 and 10 following the movement of the piston 8, are inserted in series at the front and rear of the cylinder 1, making the oil passage and structure simple. This can reduce failures and manufacturing costs. Moreover, it is configured as described above, and during the period from when the piston 8 is accelerated in the forward direction until it finishes retracting, the pressure oil supply oil passages 15, 1
It is possible to store a part of the pressure oil sent to the pistons 8 to 20 in the forward biasing means 16 provided in the middle of the oil passage, and to apply this to the piston 8 from the pressure supply source during the next acceleration. Since it can be made to work together with the pressure oil, the energy of the pressure oil can be used effectively, and the impact force and energy efficiency can be improved.

Next, the hydraulic impact device of the present invention will be explained with reference to an embodiment shown in FIGS.
4 are continuously provided on the same axis, and the inner holes 2,
3 has a hollow cylindrical valve 5 with its upper and lower ends closed,
A cylindrical piston 8 is fitted into the inner holes 3 and 4 so as to be able to move forward and backward, respectively. In addition, when using this striking device as a breaker etc., the piston 8
A striking tool 32 is fitted into the front cylinder 1 so as to be movable back and forth. Note that 33 and 70 are the same tool 32
These are pins and grooves that regulate the amount of forward and backward movement. In addition, the inner hole 3 has annular groove ports 9, 10, 11, 12.
However, each of the inner holes 4 is provided with an annular groove port 13. Also, the pressure oil inlet 14 is connected to the oil passage 15.
The liquid chamber 6 passes through the oil passages 18 and 19 to the port 9, and the oil passage 18 passes through the oil passage 20 to the port 13.
The liquid chamber 6 is connected to the accumulator 16 via an oil passage 17.
The port 10 is connected to the port 12 through the oil passage 21, and the chamber 7 is connected to the outlet port 23 through the oil passage 22.
The ports 11 communicate with the outlet ports 23 via oil passages 24, respectively. Further, 5 is a valve, and the valve 5 has a small diameter shaft portion 25 and a large diameter shaft portion 26, and the small diameter shaft portion 25 is located in the inner hole 2.
The large diameter shaft portion 26 is fitted into the inner hole 3 so as to be movable forward and backward. Further, the large diameter shaft portion 26 is provided with the ports 9 and 10 when the valve 5 moves back and forth.
An annular groove 28 is provided to communicate or block the two. 8 is a piston, and the piston 8 has a large diameter shaft part 29 and a small diameter shaft part 30, and the large diameter shaft part 2
9 is attached to the inner hole 3, and the small diameter shaft portion 30 is attached to the inner hole 4.
They are inserted into each other so that they can move forward and backward. Further, the small diameter shaft portion 30 is provided with an annular groove 31 that communicates or blocks the ports 12 and 13 when the piston 8 moves forward or backward. Further, as shown in FIG. 4, a valve 5 inside the piston 8 is retracted by the piston 8 to shut off the annular groove ports 9 and 10, and at the same time connect the annular groove port 10 to the forward rear pressure receiving surface 8a of the piston 8. Communication passages 71, 7 that communicate with the annular groove ports 13, 10 when opened
2,73 are provided.

Next, the operation of the hydraulic impact device will be explained. 1st
Figures 7 to 7 show one impact cycle of the present hydraulic impact device. To begin with, the state shown in FIG. 1 in which the piston 8 has begun to retreat is explained. At this time, pressure oil sent from a pressure oil supply source (not shown) to the pressure oil inlet 14 enters the oil passage 15 → the liquid chamber 6. , that is valve 5
acts on the end face 36 of the small diameter shaft portion 25 of the valve 5, causing the valve 5 to move forward in the direction of the arrow 37, so that the ports 9 and 10 communicate with each other via the annular groove 28 of the valve 5. Therefore, pressure oil passes through oil passages 18, 19 → port 9 → annular groove 28 of valve 5 → port 10 → oil passage 21 and then reaches port 1.
2, the pressure acts on the intermediate pressure receiving surface 8b between the large diameter shaft portion 29 and the small diameter shaft portion 30 of the piston 8, and the piston 8 begins to retreat in the direction of the arrow 34. Therefore, the oil between the piston 8 and the valve 5 is discharged from the outlet 23 through the oil passage 24 to an oil tank (not shown). As the piston 8 retreats in the above direction, the front end 4 of the small diameter shaft portion 30 of the piston 8
8 separates from the end surface of the inner hole 4 of the cylinder 1 and the ports 13 and 12 communicate with each other, pressure oil is sent from the oil passage 20 to the annular groove 31 of the piston 8 to the port 12,
The piston 8 moves back further. Further, when the piston 8 is retracted as described above and later, a part of the pressure oil is accumulated in the accumulator 16 via the oil passage 17. FIG. 2 shows the moment when the large-diameter shaft portion 29 of the piston 8 fits into the inner hole 3 of the cylinder 1. At this time,
The piston 8 can transmit the movement in the direction of the arrow 34 to the valve 5 via the protrusion 74 on the piston 8 side and the protrusion 75 on the valve 5 side. At this time, the force acting on the piston 8, that is, the force acting on the intermediate pressure receiving surface 8b, is larger than the force acting on the end portion 36 of the small diameter shaft portion 25 of the valve 5. Moreover, since the mass of the valve 5 is considerably smaller than the mass of the piston 8, the piston 8 can move the valve 5 without decelerating.
At the same time, it continues to retreat in the direction of arrow 34. Therefore, the oil in the chamber 7 is discharged from the outlet 23 to the oil tank via the oil passage 22. Further, when the piston 8 and the valve 5 retreat to the position shown in FIG. communicates with the rear pressure receiving surface 8a, and the pressure in this portion increases. However, in the valve 5, the large diameter shaft portion 26
Since the lower end side has a larger pressure receiving area than the upper end side of the small diameter shaft portion 25, the valve 5 receives a large force in the direction of the arrow and retreats rapidly, the port 10 opens rapidly and pressure oil flows in. . Therefore, the piston 8 also receives a large force in the direction opposite to the arrow 39 on the rear pressure receiving surface 8a. By then, the accumulator 16 has been filled with pressure oil, and the valve 5
When the oil rapidly retreats as described above, pressure oil flows from the accumulator 16 to the oil path 1
8, 20, 21→port 10 and is sent between the valve 5 and the piston 8. Also, valve 5 is the fourth
When retreating to the position shown in the figure, the above-mentioned systems 18, 20, 21, 1 are connected to the pressure oil supply source and accumulator 16.
Pressure oil sent between the valve 5 and the piston 8 through 0 and 20 through 71, 72, and 73 acts on the rear pressure receiving surface 8a of the piston 8, causing the piston 8 to move forward while being accelerated. start. Also piston 8
5, the end face 45 of the port 11 touches the upper end 46 of the large diameter shaft 29 of the piston 8.
The ports 11 and 10 communicate with each other, and the chamber 38
The oil inside is discharged from the outlet 23 to the oil tank via the oil passage 24. Therefore, the pressure inside the chamber 38 decreases,
Although the force acting on the piston 8 and the valve 5 disappears, the piston 8 continues to move forward at a high speed, and from then on, it advances to the position shown in FIG. 6 due to inertia. Further, at this time, the small diameter shaft portion 30 of the piston 8 closes the space between the ports 12 and 13, and the pressure within the chamber 38 further decreases. Therefore, the valve 5 starts to move forward in the direction of the arrow 42 due to the pressure oil supplied from the pressure oil supply source to the inlet 14 and acting on the end surface 36 of the small diameter shaft portion 25 of the valve 5. Further, the remaining pressure oil is sent to the accumulator 16 and accumulated therein. When the piston 8 advances to the position shown in FIG.
2 to hit the object to be hit. Meanwhile, the valve 5 continues to move in the direction of the arrow 42, and at the same time the annular groove 28 of the large-diameter shaft 26 of the valve 5 communicates with the ports 9 and 10, the flange 27 of the valve 5 connects with the annular groove 44 of the lower end of the chamber 7. The valve 5 comes into soft contact with the lower end wall 43 of the chamber 7 as the valve 5 begins to enter the chamber 7 and is braked hydrodynamically. In addition, pressure oil from the inlet 14 flows through the oil passage 15.
→Liquid chamber 6→Oil passages 18, 19→Port 9→Annular groove 2
8 → Port 10 → It is sent to port 12 via oil passage 21, acts on intermediate pressure receiving surface 8b of piston 8, piston 8 starts to retreat in the direction of arrow 34, and the first
Return to the state shown in the figure. After that, it operates in the same manner and strikes the object to be struck.

When temporarily stopping the impact, the impact device is moved away from the object to be impacted and the impact tool 32 is advanced to the non-impact position shown in FIG. Inner hole 3
The piston 8 is fitted into the piston 8, and a brake is applied hydrodynamically to stop the piston 8.

Although the embodiments of the present invention have been described above, the present invention is, of course, not limited to these embodiments, and can be modified in various ways without departing from the spirit of the present invention. . For example, if the valve 5 is composed of a plunger 53 and a valve body 54 as shown in FIG.
The inner hole 2 of the cylinder 1 accommodating the valve body 54 and the inner hole 3 of the cylinder 1 accommodating the valve body 54 do not have to be arranged on the same axis, and high precision is not required. Manufacture can be made easier. In addition, as shown in FIG.
If a spring 55 is provided instead of 3, the liquid chamber 6 can be omitted.

[Brief explanation of the drawing]

1 to 7 are vertical side views showing the operating sequence of an embodiment of the hydraulic impact device according to the present invention, and FIG. 8 is a vertical side view showing the stopped state of the hydraulic impact device,
9 and 10 are longitudinal sectional side views showing other embodiments of the hydraulic impact device according to the present invention. 1... Cylinder, 5... Valve, 8... Piston, 8a... Rear pressure receiving surface for forward movement, 8b... Intermediate pressure receiving surface for reverse movement, 9, 10, 12, 13... High pressure port, 11... Low pressure port , 14...Pressure oil inlet, 1
5, 18-20... Pressure oil supply oil passage, 21... Communication passage, 23... Return oil outlet, 24... Return oil passage, 71, 72, 73... Communication passage.

Claims (1)

[Claims] 1 High pressure ports 9, 10, low pressure port 11, high pressure ports 12, 13 are provided in the cylinder 1 in that order, and the same high pressure ports 13, 9 are connected to the pressure oil supply oil passage 20,
19, 18, and 15 to the pressure oil inlet 14, the high pressure port 12 to the high pressure port 10 via the communication passage 21, and the low pressure port 11 to the return oil outlet 23 via the return oil passage 24, respectively. When the object to be struck is struck and the object begins to move backward, the high pressure ports 12 and 13 are communicated, and at the same time the low pressure port 11 is closed, and the same high pressure ports 12 and 13 are communicated to each other immediately before the object is moved forward and the object to be struck is started to be struck. The piston 8 opens the low-pressure port 11 at the same time as the piston 8 shuts off the communication between the high-pressure ports 9 and 10. The high pressure port 10 is opened to the forward moving rear pressure receiving surface 8a of the piston 8, and the piston 8 moves forward to open the low pressure port 10.
After the valve 1 is opened, the valve 5 is moved forward by the force acting on its rear end to communicate the high pressure ports 9 and 10, and at the same time closes the high pressure port 10 to the forward moving rear pressure receiving surface 8a of the piston 8. In this hydraulic impact device, the valve 5 is moved backward by the piston 8 and the high pressure port 9,
10 and at the same time cut off communication with the same high pressure port 10.
A hydraulic impact device characterized in that communication passages 71, 72, 73 are provided in the piston 8, which communicate the high pressure ports 13, 10 when the piston 8 is opened to the forward rear pressure receiving surface 8a of the piston 8.