KR102767045B1 - Air system for drilling machine - Google Patents

Abstract

The present invention relates to an air system for a drill. An unload valve controls the amount of air intake to an air compressor according to the supplied air pressure. A receiver tank stores compressed air discharged from an air compressor. A low-pressure solenoid valve opens and closes the flow of compressed air supplied by branching from the receiver tank. A low-pressure proportional valve is connected to the outlet side of the low-pressure solenoid valve and controls the unload valve with compressed air below a low-pressure setting value. A high-pressure solenoid valve opens and closes the flow of compressed air supplied by branching from the receiver tank. The high-pressure proportional valve is connected to the outlet side of the high-pressure solenoid valve and controls the unload valve with compressed air below a high-pressure setting value. A control unit controls the low-pressure solenoid valve and the high-pressure solenoid valve according to the settings of a low-pressure air generation mode and a high-pressure air generation mode.

Description

{Air system for drilling machine}

The present invention relates to an air system for a perforator, and more particularly, to a system employed in a perforator for supplying compressed air.

In general, drills are used to break rock or make blast holes for the purpose of excavating and removing rocks at various tunnel construction sites such as ore extraction in quarries, road opening or tunnel construction in rocky areas, and subway construction sites.

The most commonly used drilling methods are Down-the-hole Hammer (DTH), Top Hammer, and Rotary Drill. Among them, the DTH drilling method uses a drill rig that rotates the entire tube, and a pneumatic hammer in contact with the rock strikes it with compressed air to fracture the rock with impact energy, and the compressed air discharged after striking blows away the rock fragments to drill.

This type of DTH drilling machine is equipped with an air system that generates compressed air for driving the pneumatic hammer and supplies it to the pneumatic hammer. A typical air system is configured to generate compressed air at a specified maximum operating pressure and supply it to the drilling machine.

Meanwhile, depending on the working conditions, the drill may be able to operate sufficiently with compressed air at a lower pressure than the maximum working pressure. However, since the conventional air system is configured to generate compressed air only at the set maximum working pressure, fuel efficiency may be reduced due to unnecessary power consumption. Therefore, depending on the working conditions of the drill, an air system that can generate air pressure at relatively low pressure and relatively high pressure is required.

Patent Registration No. 10-2330933 (November 24, 2021, Announcement)

The object of the present invention is to provide an air system for a drill, which can reduce fuel consumption by generating low and high air pressures and supplying them to a drill according to the working conditions of the drill.

In order to achieve the above object, the air system for a drill according to the present invention comprises an air compressor, an unload valve, a receiver tank, a low-pressure solenoid valve, a low-pressure proportional valve, a high-pressure solenoid valve, a high-pressure proportional valve, a shuttle valve, and a control unit. The air compressor compresses intake air and discharges it. The unload valve adjusts the air intake amount to the air compressor according to the air pressure supplied. The receiver tank stores the compressed air discharged from the air compressor. The low-pressure solenoid valve opens and closes the flow of compressed air branched from the receiver tank. The low-pressure proportional valve is connected to the outlet side of the low-pressure solenoid valve and controls the unload valve with compressed air below a low-pressure setting value. The high-pressure solenoid valve opens and closes the flow of compressed air branched from the receiver tank and supplied. The high-pressure proportional valve is connected to the outlet side of the high-pressure solenoid valve and controls the unload valve with compressed air below the high-pressure setting. The shuttle valve discharges the compressed air supplied from the low-pressure proportional valve and the high-pressure proportional valve without interference and supplies it to the unload valve. The control unit controls the low-pressure solenoid valve and the high-pressure solenoid valve according to the settings of the low-pressure air generation mode and the high-pressure air generation mode.

Here, the low-pressure solenoid valve may be a normally open type, and the high-pressure solenoid valve may be a normally closed type. The control unit may close the low-pressure solenoid valve and open the high-pressure solenoid valve according to the setting of the high-pressure air generation mode.

The low-pressure proportional valve is configured to discharge compressed air to the outside when the pressure of the supplied compressed air exceeds the low-pressure setpoint, and the high-pressure proportional valve can be configured to discharge compressed air to the outside when the pressure of the supplied compressed air exceeds the high-pressure setpoint.

In an additional aspect, the air system for the blower may include a low-pressure orifice for reducing the pressure of compressed air supplied from the low-pressure proportional valve to the unload valve, and a high-pressure orifice for reducing the pressure of compressed air supplied from the high-pressure proportional valve to the unload valve.

In an additional aspect, the air system for the air compressor may include a normally closed type solenoid valve that is connected between the shuttle valve and the unload valve to close the flow of compressed air supplied from the shuttle valve when the air compressor is turned off and wait for the flow, and is opened by the control unit when the air compressor is turned on to open the flow of compressed air supplied from the shuttle valve.

In an additional aspect, the air system for the air compressor may include a normally open type bleed valve that allows external discharge of compressed air supplied from the receiver tank when the air compressor is in the OFF operation, and is closed by the control unit when the air compressor is in the ON operation to block external discharge of compressed air supplied from the receiver tank.

The air system for a drill according to the present invention generates low and high air pressures according to the working conditions of the drill and supplies them to the drill, thereby minimizing unnecessary power consumption and reducing fuel consumption.

FIG. 1 is a configuration diagram of an air system for a perforator according to one embodiment of the present invention.
Figure 2 is a control block diagram of the air system for the perforator shown in Figure 1.

The present invention will be described in detail with reference to the attached drawings as follows. Here, the same reference numerals are used for the same components, and repetitive descriptions and detailed descriptions of well-known functions and components that may unnecessarily obscure the gist of the present invention are omitted.

The embodiments of the present invention are provided to more completely explain the present invention to those with average knowledge in the art. Accordingly, the shapes and sizes of elements in the drawings may be exaggerated for a clearer explanation.

FIG. 1 is a block diagram of an air system for a perforator according to one embodiment of the present invention. FIG. 2 is a control block diagram of the air system for a perforator illustrated in FIG. 1.

Referring to FIGS. 1 and 2, an air system (100) for a perforator according to one embodiment of the present invention includes an air compressor (110), an unload valve (120), a receiver tank (130), a low-pressure solenoid valve (141), a low-pressure proportional valve (142), a high-pressure solenoid valve (151), a high-pressure proportional valve (152), a shuttle valve (160), and a control unit (170).

The air compressor (110) compresses the air that is sucked in and discharges it. That is, the air compressor (110) sucks in outside air and compresses it to a high pressure. The air compressor (110) may be configured to compress the air in various known ways, such as a way of reducing the space volume. The air compressor (110) may be driven by a compressor engine (111). The compressor engine (111) may be controlled by a control unit (170). The air compressor (110) may suck in air from which foreign substances are filtered by an air filter (101) through an air intake line.

The air compressor (110) can be supplied with oil for lubrication by various known oil supply devices (not shown). The oil supply device supplies oil to mechanical elements that experience mutual friction inside the air compressor (110), thereby preventing damage caused by friction during the process of the air compressor (110) generating high-pressure air.

The unload valve (120) controls the amount of air intake to the air compressor (110) according to the supplied air pressure. The unload valve (120) can operate to open more as the supplied air pressure increases, thereby increasing the amount of air intake, and can operate to open less as the supplied air pressure decreases, thereby decreasing the amount of air intake.

The unload valve (120) may be a normally closed (NC) type. The unload valve (120) may be configured to adjust the opening by operating the swash plate by a servo cylinder (121). The unload valve (120) may wait for the swash plate to be in a closed position by a spring of the servo cylinder (121), and then open the swash plate by the cylinder rod by air pressure supplied to the servo cylinder (121). The air intake amount of the unload valve (120) is controlled by a low-pressure proportional valve (142) and a high-pressure proportional valve (152).

The receiver tank (130) stores compressed air discharged from the air compressor (110). The receiver tank (130) temporarily stores the compressed air and supplies it to the perforator (10) as needed. The compressed air discharged from the air compressor (110) can be supplied to the receiver tank (130) while being prevented from flowing backward by the check valve (102). The receiver tank (130) can remove oil from the compressed air by the oil separator and recover it.

In an additional aspect, the cyclone tank (131) can receive compressed air from the receiver tank (130), remove residual oil from the compressed air, and then send it to the low-pressure solenoid valve (141) and the high-pressure solenoid valve (141).

The minimum press valve (MPV, 103) can maintain the minimum pressure of the compressed air discharged from the receiver tank (130). The pressure of the receiver tank (130) increases by driving the air compressor (110), and the minimum press valve (103) is maintained in a closed state until the pressure of the receiver tank (130) reaches the set pressure. When the pressure of the receiver tank (130) exceeds the set pressure, the minimum press valve (103) is opened to supply low-pressure/high-pressure compressed air to the perforator (10).

The low-pressure solenoid valve (141) opens and closes the flow of compressed air supplied from the receiver tank (130). When the low-pressure air generation mode is set, the low-pressure solenoid valve (141) opens the flow of compressed air supplied from the receiver tank (130) and transmits it to the low-pressure proportional valve (142). When the high-pressure air generation mode is set, the low-pressure solenoid valve (141) closes the flow of compressed air supplied from the receiver tank (130) and blocks the air supply to the low-pressure proportional valve (142).

The low-pressure solenoid valve (141) may be a normally open (NO) type. The low-pressure solenoid valve (141) can be closed by the control unit (170) when the high-pressure air generation mode is set, thereby blocking the air supply to the low-pressure proportional valve (142).

The low-pressure proportional valve (142) is connected to the outlet side of the low-pressure solenoid valve (141) and controls the unload valve (120) with compressed air below the low-pressure setting value. The low-pressure proportional valve (142) can be opened and adjusted to the low-pressure setting value, for example, 15 bar. In addition, the low-pressure proportional valve (142) can be configured to discharge the compressed air to the outside when the pressure of the supplied compressed air exceeds the low-pressure setting value.

The low-pressure proportional valve (142) supplies compressed air to the unload valve (120) until the pressure of the compressed air supplied from the low-pressure solenoid valve (141) reaches the low-pressure setpoint. At this time, the unload valve (120) adjusts the air intake amount according to the supplied air pressure. The low-pressure proportional valve (142) exhausts the compressed air to the outside when the pressure of the compressed air supplied from the low-pressure solenoid valve (141) exceeds the low-pressure setpoint. Therefore, compressed air that has risen to the low-pressure setpoint is generated and stored in the receiver tank (130), so that the low-pressure compressed air can be supplied to the perforator (10).

A low-pressure orifice (143) can decompress compressed air supplied from a low-pressure proportional valve (142) to an unload valve (120). The low-pressure orifice (143) is connected to an outlet of the low-pressure proportional valve (142). The low-pressure orifice (143) can discharge some of the compressed air supplied from the low-pressure proportional valve (142) to the outside, thereby allowing the decompressed compressed air to be supplied to the unload valve (120).

That is, the low-pressure orifice (143) minimizes the fluctuation range of air pressure to control the unload valve (120) that requires relatively low air pressure, thereby enabling stable control of the unload valve (120).

The high-pressure solenoid valve (151) opens and closes the flow of compressed air supplied from the receiver tank (130). When the high-pressure air generation mode is set, the high-pressure solenoid valve (151) opens the flow of compressed air supplied from the receiver tank (130) and transmits it to the high-pressure proportional valve (152). When the low-pressure air generation mode is set, the high-pressure solenoid valve (151) closes the flow of compressed air supplied from the receiver tank (130) and blocks the air supply to the high-pressure proportional valve (152).

The high-pressure solenoid valve (151) may be a normally closed (NC) type. The high-pressure solenoid valve (151) can supply compressed air to the high-pressure proportional valve (152) by being opened by the control unit (170) when the high-pressure air generation mode is set.

The high pressure proportional valve (152) is connected to the outlet side of the high pressure solenoid valve (151) and controls the unload valve (120) with compressed air below the high pressure setting value. The high pressure proportional valve (152) can be opened and adjusted to match the high pressure setting value, for example, 23 bar. In addition, the high pressure proportional valve (152) can be configured to discharge the compressed air to the outside when the pressure of the supplied compressed air exceeds the high pressure setting value.

The high-pressure proportional valve (152) supplies compressed air to the unload valve (120) until the pressure of the compressed air supplied from the high-pressure solenoid valve (151) reaches the high-pressure setpoint. At this time, the unload valve (120) adjusts the air intake amount according to the supplied air pressure. The high-pressure proportional valve (152) exhausts the compressed air to the outside when the pressure of the compressed air supplied from the high-pressure solenoid valve (151) exceeds the high-pressure setpoint. Therefore, compressed air that has risen to the high-pressure setpoint is generated and stored in the receiver tank (130), so that the high-pressure compressed air can be supplied to the perforator (10).

A high pressure orifice (153) can decompress compressed air supplied from a high pressure proportional valve (152) to an unload valve (120). The high pressure orifice (153) is connected to an outlet of the high pressure proportional valve (152). The high pressure orifice (153) can discharge some of the compressed air supplied from the high pressure proportional valve (152) to the outside, thereby allowing the decompressed compressed air to be supplied to the unload valve (120).

That is, the high pressure orifice (153) minimizes the fluctuation range of air pressure to control the unload valve (120) that requires relatively low air pressure, thereby enabling stable control of the unload valve (120).

The shuttle valve (160) discharges compressed air supplied from the low-pressure proportional valve (142) and the high-pressure proportional valve (152) without interference and supplies it to the unload valve (120). The shuttle valve (160) connects the low-pressure proportional valve (142) to the first inlet and connects the high-pressure proportional valve (152) to the second inlet.

When the low-pressure air generation mode is set, the shuttle valve (160) can discharge compressed air supplied from the low-pressure proportional valve (142) from the outlet as the valve body is positioned to open the first inlet while closing the second inlet. When the high-pressure air generation mode is set, the shuttle valve (160) can discharge compressed air supplied from the high-pressure proportional valve (152) from the outlet as the valve body is positioned to close the first inlet while opening the second inlet.

A solenoid valve (104) is connected between the shuttle valve (160) and the unload valve (120) to open and close the flow of compressed air supplied from the shuttle valve (160) to the unload valve (120). The solenoid valve (104) may be a normally closed (NC) type.

The solenoid valve (104) waits in a closed state for the flow of compressed air supplied from the shuttle valve (160) when the air compressor (110) is turned off. The solenoid valve (104) is opened by the control unit (170) when the air compressor (110) is turned on, thereby opening the flow of compressed air supplied from the shuttle valve (160), thereby allowing the compressed air to be supplied to the unload valve (120).

A bleed valve (105) can allow or block external discharge of compressed air supplied from the receiver tank (130). The bleed valve (105) can be a normally open (NO) type.

The bleed valve (105) allows external discharge of compressed air supplied from the receiver tank (130) when the air compressor (110) is in the OFF operation. The bleed valve (105) is closed by the control unit (170) when the air compressor (110) is in the ON operation to block external discharge of compressed air supplied from the receiver tank (130), thereby allowing compressed air to be supplied to the unload valve (120) in the open operation state.

The control unit (170) controls the low-pressure solenoid valve (141) and the high-pressure solenoid valve (151) according to the settings of the low-pressure air generation mode and the high-pressure air generation mode. The control unit (170) controls the overall system. When the control unit (170) receives an ON operation command for the air compressor (110) from the operating unit, the control unit (170) can drive the air compressor (110), open the solenoid valve (104) in the closed state, and close the bleed valve (105) in the open state.

Then, as compressed air from the air compressor (110) is supplied to the unload valve (120) through the receiver tank (130), the open low-pressure solenoid valve (141), the low-pressure proportional valve (142), the shuttle valve (160), and the open solenoid valve (104), the closed unload valve (120) is opened. Accordingly, external air can be sucked into the air compressor (110) through the open unload valve (120), compressed, and then stored in the receiver tank (130). The compressed air in the receiver tank (130) is increased to the low-pressure setpoint by the low-pressure proportional valve (142). The control unit (170) maintains the compressed air in the receiver tank (130) at the low-pressure setpoint according to the setting of the low-pressure air generation mode and supplies it to the perforator (10).

The control unit (170) can close the low-pressure solenoid valve (141) and open the high-pressure solenoid valve (151) according to the setting of the high-pressure air generation mode. Then, as the compressed air of the receiver tank (130) is supplied to the unload valve (120) through the open high-pressure solenoid valve (151), the high-pressure proportional valve (152), the shuttle valve (160), and the open solenoid valve (104), the opening of the unload valve (120) is increased to increase the air intake amount. The compressed air of the receiver tank (130) is increased to the high-pressure set value by the high-pressure proportional valve (152). The control unit (170) maintains the compressed air of the receiver tank (130) at the high-pressure set value and supplies it to the perforator (10).

When the control unit (170) receives an off operation command for the air compressor (110), it can stop the air compressor (110), close the solenoid valve (104) in the open state, and open the bleed valve (105) in the closed state.

In this way, the air system (100) for the perforator of the present embodiment generates low or high pressure air pressure according to the working conditions of the perforator (10) and supplies it to the perforator (10), thereby minimizing unnecessary power consumption and reducing fuel consumption.

Although the present invention has been described with reference to the embodiments illustrated in the attached drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the true scope of protection of the present invention should be determined only by the appended claims.

10..Puncher
100.. Air system for perforator
101..Air filter 102..Check valve
103..Minimum pressure maintenance valve 104..Solenoid valve
105..Bleed valve 110..Air compressor
111..Compressor Engine 120..Unload Valve
121..Servo Cylinder 130..Receiver Tank
131..Cyclone Tank 141..Low Pressure Solenoid Valve
142.. Low pressure proportional valve 143.. Low pressure orifice
151..High pressure solenoid valve 152..High pressure proportional valve
153..High pressure orifice 160..Shuttle valve
170..Control Unit

Claims (6)

An air compressor that compresses the intake air and discharges it;
An unload valve for controlling the air intake to the air compressor according to the supplied air pressure;
A receiver tank for storing compressed air discharged from the above air compressor;
A low-pressure solenoid valve for opening and closing the flow of compressed air supplied by branching from the above receiver tank;
A low-pressure proportional valve connected to the outlet side of the above low-pressure solenoid valve to control the above unload valve with compressed air below the low-pressure setting value;
A high-pressure solenoid valve for opening and closing the flow of compressed air supplied by branching from the above receiver tank;
A high pressure proportional valve connected to the outlet side of the high pressure solenoid valve to control the unload valve with compressed air below the high pressure setting value;
A shuttle valve that discharges compressed air supplied from the above low-pressure proportional valve and the above high-pressure proportional valve without interference and supplies it to the above unload valve; and
It includes a control unit that controls the low-pressure solenoid valve and the high-pressure solenoid valve according to the setting of the low-pressure air generation mode and the high-pressure air generation mode;
The above low-pressure proportional valve is configured to discharge compressed air to the outside when the pressure of the supplied compressed air exceeds the low-pressure setpoint.
An air system for a drill, characterized in that the high-pressure proportional valve is configured to discharge compressed air to the outside when the pressure of the supplied compressed air exceeds a high-pressure set value.
In the first paragraph,
The above low pressure solenoid valve is of the normally open type.
The above high pressure solenoid valve is of the normally closed type.
An air system for a perforator, characterized in that the control unit closes the low-pressure solenoid valve and opens the high-pressure solenoid valve according to the setting of the high-pressure air generation mode.
delete In the first paragraph,
A low-pressure orifice for reducing the compressed air supplied from the low-pressure proportional valve to the unload valve, and
An air system for a drill, characterized by including a high-pressure orifice for reducing compressed air supplied from the high-pressure proportional valve to the unload valve.
In the first paragraph,
An air system for a drill, characterized in that it includes a normally closed type solenoid valve that is connected between the shuttle valve and the unload valve, waits in a closed state for the flow of compressed air supplied from the shuttle valve when the air compressor is turned off, and opens the flow of compressed air supplied from the shuttle valve by the control unit when the air compressor is turned on.
In the first paragraph,
An air system for a drill, characterized in that it includes a normally open type bleed valve that allows external discharge of compressed air supplied from the receiver tank when the air compressor is in the OFF operation, and blocks external discharge of compressed air supplied from the receiver tank by being closed by the control unit when the air compressor is in the ON operation.

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