JPS5833065B2 - hydraulic striking device - 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 provided in a separate part from the cylinder, which complicates the structure and oil passage, and there is a problem that the operation of the piston becomes unstable. Ta.

The present invention addresses the above-mentioned problems and is directed to the high pressure port 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 the pressure oil inlet 14 via pressure oil supply oil passages 20 and 19゜18. 12 is connected to the same high pressure port 10 via a communication passage 21, and the same low pressure port 11 is connected to a return oil outlet 23 via a return oil passage 24. A piston 8 which communicates ports 12 and 13 and simultaneously closes the low pressure port 11, and cuts off communication with the high pressure port 12 and 13 and simultaneously opens the low pressure port 11 immediately before moving forward to strike the object to be struck; is moved back and the low pressure port 11 is closed, and then the same piston 8 moves back and blocks communication between the high pressure ports 9 and 10. At the same time, the high pressure port 10
is opened to the forward rear pressure receiving surface 8a of the piston 8, and after the piston 8 moves forward and the low pressure port 11 is opened, it is moved forward by the forward biasing means 16 and the high pressure ports t-9, 10 are opened. A valve 5 that communicates with the high pressure port 10 and simultaneously closes the same high pressure port 10 with respect to the forward movement rear pressure receiving surface 8a of the piston 8 is inserted in series into the cylinder 1, and the high pressure port 1
The present invention relates to a hydraulic impact device characterized in that 2 is always open on the rear pressure receiving surface 8b for backward movement of the piston 8, and its purpose is to simplify the oil passage and structure, reduce failures, Production costs can be reduced.

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,
The piston 8 hits the object to be hit, and the pressure oil reaches 14.15,
18, 19, 9, 10, 21° 12 is sent 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 brought into communication, and the low pressure port 1
1 is switched to close, pressure oil is 18.20, 13.12
It is also sent to the backward intermediate pressure receiving surface 8b of the piston 8,
The piston 8 continues to move backward while being accelerated, and from the middle of the movement, the valve 5 also begins to move backward, and when the piston 8 finishes moving backward,
The valve 5 has also finished retracting, the high pressure ports 9 and 10 are closed, and the high pressure port 10 is connected to the forward rear pressure receiving surface 8 of the piston 8.
a, the pressure oil is switched to 14, 15, 18.
, 20, 13° 12.2 When the pressure is supplied from L10 to the forward rear pressure receiving surface 8a of the piston 8, the piston 8 starts moving forward while being accelerated, and when the piston 8 advances until just before hitting the object to be hit, the high pressure port N2, 13 is To shut off, the low pressure port 11 is switched open, the valve 5 is advanced by the forward biasing means 16, the high pressure port 9,10 is shut off, and the high pressure port 10 is switched to the forward rear pressure receiving surface of the piston 8. 8a, the pressure oil is switched to 14.15, 18, 19, 9.
, 10°21.12 to the backward intermediate pressure receiving surface 8b of the piston 8, but the piston 8 continues to move forward due to inertia and strikes the object to be struck.

In this way, the hydraulic impact device of the present invention has a impact piston 8 that moves forward and backward to switch between the low pressure port 11 and the high pressure port 12, 13, and a high pressure port 9 that follows the movement of the piston 8.
, 10 are inserted in series in the front and rear parts of the cylinder 1, so the oil passage and structure can be simplified, failures can be reduced, and manufacturing costs can be reduced.

Moreover, with the above-mentioned structure, the pressure oil supplied from the pressure oil supply source to the pressure oil supply oil passages 15. A part of the oil can be stored in the forward biasing means 16 provided in the middle of the oil passage, and this can be applied to the piston 8 during the next acceleration together with the pressure oil from the pressure supply source. It is possible to effectively utilize the energy of oil and improve striking force and energy efficiency.

Next, the hydraulic impact device of the present invention will be explained with reference to an embodiment shown in FIGS. A cylindrical valve 5 is provided continuously on the line, and the inner hole 2°3 has a cylindrical valve 5.
A cylindrical piston 8 is fitted into the inner holes 3 and 4 so as to be able to move forward and backward, respectively.

Note that the diameters of the inner holes 3 and 4 are the same. Further, when this striking device is used as a breaker or the like, a striking tool 32 is fitted into the cylinder 1 in front of the piston 8 so as to be movable back and forth.

Note that 33.degree. 70 is a pin and groove that regulate the amount of forward and backward movement of the tool 32.

In addition, the inner hole 3 has an annular groove port 9゜10.11.12.
However, each of the inner holes 4 is provided with an annular groove port 13.

Further, the pressure oil inlet 14 is connected to the port 9 via the oil passage 15, the liquid chamber 6, and the oil passages 18, 19, the oil passage 18 is connected to the port 13 via the oil passage 20, and the liquid chamber 6 is connected to the accumulator via the oil passage 17. 16, the port 10 passes through the oil passage 21 to the port 12, the chamber 7 passes through the oil passage 22 to the outlet port 23, the port 11 passes through the oil passage 24 to the outlet port 23,
We are in contact with each other.

Further, 5 is a valve, and the valve 5 has a small diameter shaft portion 25, a large diameter shaft portion 26, and a flange portion 27. They are fitted into the inner hole 3 so as to be movable forward and backward.

Further, the large-diameter shaft portion 26 is provided with an annular groove 28 that connects or blocks the ports 9 and 10 when the valve 5 moves forward or backward.

8 is a piston, and the piston 8 has a large diameter shaft portion 29 and a small diameter shaft portion 30, the large diameter shaft portion 29 is connected to the inner hole 3, and the small diameter shaft portion 30 is connected to the inner hole 4. , are inserted so that they can move forward and backward.

Further, in the small diameter shaft portion 30, there is an annular groove 31 that communicates or blocks the ports 12 and 13 when the piston 8 moves back and forth.
is provided.

Next, the operation of the hydraulic impact device will be explained.

1 to 7 show one striking cycle of the present hydraulic striking 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. , which acts on the end face 36 of the small diameter shank 25 of the valve 5, causing the valve 5 to move forward in the direction of the arrow 37, so that the ports 9, 10 communicate via the annular groove 28 of the valve 5.

Therefore, pressure oil is sent to port 12 via oil passages 18, 19 → port 9 → annular groove 28 of valve 5 → port 10 → oil passage 21, and is transferred to large diameter shaft portion 29 and small diameter shaft portion 30 of piston 8.
Acting on the intermediate pressure receiving surface 8b between the piston 8 and the piston 8, 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).

When the piston 8 retreats in the above direction, the front end 48 of the small diameter shaft portion 30 of the piston 8 separates from the end surface of the inner hole 4 of the cylinder 1, and the ports 13.12 communicate with each other. The annular groove 31 of the piston 8 is sent to the port 12, and the piston 8 is further moved back.

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 oil in the chamber 38, and does not collide with the valve 5.

At this time, the force acting on the piston 8, that is, the force acting on the intermediate pressure receiving surface 8b, is
is greater than the force acting on end 36 of.

Furthermore, since the mass of the valve 5 is considerably smaller than the mass of the piston 8, the piston 8 continues to retreat in the direction of the arrow 34 together with the valve 5 without decelerating.

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 chamber 38 through the groove 71, and the pressure within the chamber 38 increases.

However, in the valve 5, the pressure-receiving area in the large-diameter shaft portion 26 is larger than that in the small-diameter shaft portion 25, so the valve 5 receives a large force in the direction of arrow 39 and retreats rapidly, causing the port 10 to open rapidly. 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 when the valve 5 retreats rapidly as described above, pressure oil fills the accumulator 1 to compensate for this.
6, the oil is sent between the valve 5 and the piston 8 via the oil passage 18, 20°21→port 10.

Further, when the valve 5 is retracted to the position shown in FIG. 4, the pressure oil supply source and the accumulator 16 are
1.10, the pressure oil sent between the valve 5 and the piston 8 acts on the rear pressure receiving surface 8a of the piston 8, and the piston 8 starts to move forward while being accelerated.

Further, when the piston 8 moves forward to the position shown in FIG.
6, ports 11 and 10 communicate with each other, and oil in the chamber 38 is discharged from the outlet 23 via the oil passage 24 to the oil tank.

Therefore, the pressure in the chamber 38 decreases, and the force acting on the piston 8 and the valve 5 disappears, but the piston 8 continues to move forward at a high speed, and from then on, it moves forward by inertia to the position shown in FIG. 6.

Further, at this time, the small diameter shaft portion 30 of the piston 8 closes the gap between the ports 12 and 13, and the pressure inside 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 port 9. It begins to enter the groove 44, and the brake is applied hydrodynamically.
The valve 5 makes soft contact with the lower end wall 43 of the chamber 7.

Also, the pressure oil from population 14 is transferred from oil passage 15 → liquid chamber 6 → oil passage 18.
, 19 → Port 9 → Annular groove 28 → Port 10 → Oil passage 21
is sent to the port 12 via the intermediate pressure receiving surface 8 of the piston 8.
b, the piston 8 starts to retreat in the direction of arrow 34, returning to the state shown in FIG.

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. It fits into the inner bore 3 and applies a hydrodynamic brake to stop the piston 8.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design modifications can be made 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 cylinder 1 does not need to be arranged on the same axis, high precision is not required, and the production of the cylinder 1 can be facilitated.

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, FIG. 8 is a vertical side view showing the stopped state of the hydraulic impact device, and FIGS. 9 and 10. FIG. 2 is a longitudinal sectional side view showing another embodiment 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, 1
2.13...High pressure port, 11...Low pressure port, 14...Pressure oil inlet, 15.18~2
0...Pressure oil supply oil passage, 16...Forward biasing means, 21...Communication passage, 23...
...Return oil outlet, 24...Return oil passage.

Claims (1)

[Claims] 1 High pressure port 9, 10 Low pressure port 11 High pressure port 1-1
2.13 are installed in the cylinder 1 in that order, and the same high pressure ports 13 and 9 are connected to the pressure oil supply oil path 20°19.18.1
5 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 high pressure port 10 via the communication passage 21.
are connected to the return oil outlet 23 via the return oil passage 24, and when the object to be hit is hit and the object starts to retreat, the high pressure port 12 and 13 are connected, and the low pressure port 11 is connected at the same time.
Immediately before moving forward to strike the object to be struck, a piston 8 cuts off communication between the high pressure ports 12 and 13 and at the same time opens the low pressure port 11, and the piston 8 retreats and closes the low pressure port 11. From there, the piston 8 is moved backward to cut off communication between the high pressure ports 9 and 10, and at the same time open the high pressure port 10 to the forward moving rear pressure receiving surface 8a of the piston 8, and the piston 8 moves forward to block the communication between the high pressure ports 9 and 10. After opening, it is moved forward by the forward biasing means 16 to communicate the high pressure ports 1-9 and 10, and at the same time, the high pressure port 10 is moved forward by the forward force rear pressure receiving surface 8a of the piston 8.
A hydraulic impact device characterized in that a valve 5 that closes against the piston 8 is fitted in series in the cylinder 1, and the high pressure port 12 is always open to the rearward pressure receiving surface 8b of the piston 8.