JPH0422931Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a hydraulic breaker, specifically a hydraulic breaker that can be used underwater.

Prior Art There is a known hydraulic breaker in which a striking piston is moved up and down by switching the hydraulic passage of a control valve, and the striking piston strikes the chisel head near the descending end of the striking piston, thereby crushing rocks, etc. that are being pressed by the tip of the chisel. It is.

When such a hydraulic breaker is used underwater, water enters the striking chamber formed at the contact position of the striking piston and chisel, and because the water that enters is incompressible, abnormally high pressure is generated in the striking chamber. There was a problem with the hydraulic breaker being damaged.

In order to prevent water from entering the striking chamber, methods are already known in which air is fed into the striking chamber at a pressure higher than the surrounding water pressure.

If you simply feed compressed air into the striking chamber, water may enter the striking chamber and damage the breaker due to compressor failure, hose failure, broken joints, operational errors, fluctuations in air pressure, changes in water depth, etc. I had to do a lot of work and couldn't get anything reliable.

Purpose The purpose of this invention is to solve the above-mentioned conventional problems and provide a reliable hydraulic breaker that can be used safely underwater.

Configuration The present invention achieves the above-mentioned purpose by forming a communication passageway that connects the blowing chamber and a blow groove formed in a part of the lower space that guides the chisel, and in which fluid such as water is allowed to blow into the communication passageway. This was achieved by providing a check valve to prevent the impact from flowing into the chamber and opening the striking chamber to the outside via the safety valve.

This invention prevents water from entering the interior through the gap by blowing compressed air from the striking chamber through the communication passage to the outside through the gap between the lower space and the chisel, and in the event that water resists the air pressure. Even if it tries to flow toward the striking chamber, the check valve prevents the inflow. In addition, in the unlikely event that water enters the striking chamber and the pressure in the striking chamber becomes abnormally high, the fluid can be released to the outside through a safety valve to prevent the pressure in the striking chamber from rising above a predetermined pressure. I made it.

Embodiments Details of the present invention will be explained based on embodiments shown in the drawings.

In Fig. 1, the casing 1 includes an intermediate casing 1a, a lower casing 1b, and an upper casing 1.
A striking piston 2 is placed in the intermediate casing 1a.
is guided in a reciprocating manner. Intermediate casing 1a
A lower casing 1b is fixed to the lower end, and an upper casing 1c is fixed to the upper end.

A cylindrical lower space 5 is formed in the lower casing 1b, and a chisel 6 is supported in the lower space 5 so as to be able to reciprocate and not fall off.

A lower space 5 is provided at the upper end of the lower casing 1b.
A striking chamber 7 is formed coaxially with. Lower space 5
A shoulder 8 near the upper end of the chisel 6 abuts between the chisel 6 and the striking chamber 7, and a stop ring 9 that limits upward movement of the chisel 6 is formed as an annular protrusion projecting inward.

A blow groove 10, for example, an annular recess, is formed in the lower casing 1b below the stop ring part 9 of the lower space 5, and a communication passage 11 connecting the blow groove 10 and the striking chamber 7 is formed in the lower casing 1b. The liquid flows through the blow groove 10 in the communication passage 11.
A check valve 12 that prevents water from flowing into the striking chamber 7 from
is provided.

In the striking chamber 7, a supply channel 14 communicating with a connection port 13 with a compressed air source is provided in the casing, that is, as an example, a lower casing 1b, an intermediate casing 1a,
It is formed in the upper casing 1c. Furthermore, an open passage 15 opening to the outside is opened in the striking chamber 7, and a safety valve 16 is provided in the open passage 15. safety valve 1
6 is a low pressure that does not become abnormally high, for example 7Kg/
It is formed so that it can be opened at about cm ² to relieve the fluid in the striking chamber 7.

A hydraulic device 1 has a flow path in which the vertical and reciprocating movement of the striking piston 2 is switched by a control valve.
7.

The hydraulic system itself is well known and is not the gist of the present invention, so it will not be explained in detail, but the striking piston 2
Pressure oil is constantly supplied to the lower side of the first land 2a,
By switching the flow path of the pressure oil acting on the upper side of the second land 2b, when hydraulic pressure acts on the upper side of the land 2b, the striking piston 2 is lowered, and when the upper hydraulic pressure is discharged, the striking piston 2 is lowered. It is designed to rise.

The pneumatically actuated portion and the hydraulically actuated portion of the striking piston 2 are sealed from each other by a gasket 18.

When operating underwater, compressed air is passed through the supply channel 14 into the striking chamber 7, e.g.
Kg/cm ² of compressed air is supplied.

Compressed air is further supplied from the blowing chamber 7 to the blow groove 10 via the communication passage 11 through the check valve 12. The compressed air in the blow groove 10 passes through the gap 3 between the lower space 5 and the chisel 6 and blows into the water from the lower end of the lower casing 1b. Therefore, even if the hydraulic breaker is placed underwater, water is prevented from entering the casing.

Even if water enters the communication passage 11 from the blow groove 10 for some reason, the check valve 12 prevents water from entering the striking chamber 7.

Furthermore, if water enters the striking chamber 7 for some reason, the striking piston 2 is reciprocated by the hydraulic system, and while the action of striking the chisel 6 is repeated, the pressure in the striking chamber 7 increases. When the pressure reaches a predetermined pressure, the safety valve 16 opens to release the fluid in the striking chamber 7, that is, air and water, and the pressure in the striking chamber 7 decreases. Therefore, according to the present invention, even if water enters the striking chamber 7, relief is provided before the pressure rises to an abnormal level to prevent the pressure from rising.

For example, as shown in FIG. 2, the check valve 12 provided in the communication passage 11 includes a ball 20 that contacts a valve seat 19 provided in a part of the communication passage 11, and a ball 20 that presses the ball 20 against the valve seat 19. A spring seat 22 that receives one end of the spring 21 is screwed and fixed to the lower casing 1b. This check valve allows the fluid in the communication passage 11 to flow in the direction indicated by the arrow, but is prevented from flowing in the opposite direction.

The safety valve 16 formed in the open passage 15 can be constructed as shown in FIG. 3, for example.
A valve seat sleeve 24 is inserted into a hole 23 of the lower casing 1b formed so as to follow the outer end of the open passage 15, and is fixedly held to the lower casing 1b by a retainer 25 screwed into the lower casing 1b. At this time, a valve body 26 is slidably inserted into the valve seat sleeve 24, and a spring 27 is mounted between the valve body 26 and the retainer 25.

A relief path is formed in the valve body 26 by a hole 28 that opens in the circumferential direction and a blind hole 29 that opens in the axial direction, and the relief path communicates with the outside air through a through hole 30 formed in the retainer 25. When the pressure in the striking chamber 7 rises and becomes higher than the pressure in the spring 27, the valve body 2
6 slides to open the valve seat, allowing the fluid in the striking chamber 7 to escape to the outside.

Effects The present invention prevents the compressed air from entering the breaker by blowing it outside through the blow groove and the gap between the blow groove and the lower casing through the communication passage via the check valve. Even if water tries to enter the breaker through the communication passage, it is constructed to be blocked by a check valve, and if water enters the striking chamber for some reason, a safety valve is installed to prevent damage to the breaker due to abnormally high pressure. This structure provides a perfect structure against water intrusion, resulting in a breaker that can be used safely underwater.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a hydraulic breaker according to the present invention,
FIG. 2 is a sectional view of an example of a check valve, and FIG. 3 is a sectional view of an example of a safety valve. 1... Casing, 1a... Intermediate casing,
1b... lower casing, 1c... upper casing, 2... striking piston, 3... gap, 5... lower space, 6... chisel, 7... striking chamber, 10...
Blow groove, 11... communication passage, 12... check valve,
13... Connection port, 14... Supply path, 15... Open path, 16... Safety valve, 17... Hydraulic system.

Claims (1)

[Scope of utility model registration request] A chisel that is reciprocatably inserted into a cylindrical lower space formed in the casing with a gap therebetween, and a blow that is supported by the casing so that it can reciprocate along the same axis as the chisel with a larger stroke than the chisel. A piston, a hydraulic device that reciprocates the striking piston, and a striking chamber formed as a space in the casing at a position where the striking piston and the chisel abut.
In a hydraulic breaker that can be used underwater, the hydraulic breaker has a supply path formed in a casing that connects a connection port provided in a casing that leads compressed air to the striking chamber, and a supply path formed in the striking chamber and a part of the lower space. a communication passage formed in the casing to connect the chisel with an annular blow groove surrounding the periphery of the chisel; a check valve provided in the communication passage to prevent the blow from flowing into the striking chamber; A hydraulic breaker comprising an opening path provided in a casing for opening a chamber to the outside, and a safety valve provided in the opening path.