Patent Application
20140366955
The present disclosure relates to a roof bolter, and particularly to a remote regulator for regulating drill speed, thrust pressure, and rotation pressure during a roof bolting operation.
Roof bolter machines are generally used in mining industry for securing mine roofs to be self supportive. Generally, there may be two types of operations that the roof bolters perform, namely, drilling operations and bolting operations. The drilling operations include drilling the roof and the bolting operations include inserting bolts such as cable bolts, or resin roof bolts, etc., and subsequently tightening the inserted bolts.
An operator of the roof bolter may need to change drill speed, rotation pressure and thrust pressure based on a number of factors. These factors may include the type of operation being performed, material being drilled, hardness of the material, and size of the drill etc. Conventionally, separate multiple hydraulic valves are used to change the drill speed, rotation pressure and thrust pressure of the roof bolter. This is very inconvenient and cumbersome.
U.S. Pat. No. 5,564,455 relates to a hydraulic circuit for use in controlling a horizontal boring machine which requires hydraulic fluid under pressure for rotating a drill bit or back reamer through a rotation circuit and hydraulic fluid under pressure for thrusting the drill bit or back reamer within the bore hole through a thrust circuit. Pressures from both the thrust circuit and control circuit are combined through restrictors in a mixing zone or area. The control port of a diversion valve is connected to mixing zone. When the combined pressure in the mixing zone exceeds the adjustable spring bias on the diversion valve, the diversion valve will open, diverting fluid from the thrust circuit to a low pressure zone. This will cause a reduction in the pressure in the rotation circuit as well. The reduction of both pressures will reduce the combined pressure in the mixing zone, causing the diversion valve to close and the pressures to increase. The hydraulic circuit maintains a constant maximum output for both circuits for a given horsepower input to the boring machine and productivity is enhanced due to reduced operator fatigue.
In one aspect, a regulator for controlling operation of a drill thrust actuator and a drill rotation actuator in a roof bolter, is provided. The regulator includes a first pressure relief unit, a second pressure relief unit and a flow control valve. The first pressure relief unit is configured to selectively allow a hydraulic fluid to pass to the drill thrust actuator. The second pressure relief unit is configured to selectively allow the hydraulic fluid to pass to the drill rotation actuator. Further, the flow control valve is configured to selectively adjust a flow of the hydraulic fluid to the drill rotation actuator.
In another aspect, a roof bolter is provided. The roof bolter includes a drill assembly, a main control valve and a regulator hydraulically coupled to the main control valve. The drill assembly has a drill thrust actuator and a drill rotation actuator. Further, the main control valve is configured to supply a hydraulic fluid to the drill thrust actuator and the drill rotation actuator. Furthermore, the regulator includes a first pressure relief unit, a second pressure relief unit and a flow control valve. The first pressure relief unit is configured to selectively allow a hydraulic fluid to pass to the drill thrust actuator. The second pressure relief unit is configured to selectively allow the hydraulic fluid to pass to the drill rotation actuator. Further, the flow control valve is configured to selectively adjust a flow of the hydraulic fluid to the drill rotation actuator.
In a yet another aspect, a regulator for controlling operation of a drill thrust actuator and a drill rotation actuator in a roof bolter, is provided. The regulator includes a first pressure relief cartridge valve configured to provide a first pressure relief for the drill thrust actuator. The regulator further includes a second pressure relief cartridge valve configured to provide a second pressure relief for the drill thrust actuator. The regulator includes a third pressure relief cartridge valve configured to provide a first pressure relief for the drill rotation actuator. Additionally, the regulator includes a fourth pressure relief cartridge valve configured to provide a second pressure relief for the drill rotation actuator. Furthermore, the regulator includes a flow control valve configured to selectively adjust a flow of the hydraulic fluid to the drill rotation actuator.
The present disclosure relates to a remote regulator for regulating drill speed, thrust pressure, and rotation pressure during a roof bolting operation.
The machine 100 may include drill boom assemblies 114 pivotally coupled on opposite sides of the front frame portion 106. Each of the drill boom assembly 114 includes a drill mast 116 forwardly mounted on a boom 118. The boom 118 may be pivotally mounted on the front frame portion 106 and is configured to move within a pre-determined angular range by a hydraulic mechanism. A baseplate 120 is mounted to a bottom section of the drill mast 116. The baseplate 120 supports a drill assembly 122 including a drill rotation actuator 124 and a chuck 126 which is coupled to the drill rotation actuator 124. The chuck 126 is configured to receive a drill bit or a bolt. Further, the drill assembly 122 includes a drill thrust actuator 128 to guide the drill assembly 122 along the drill mast 116.
A main control valve 130 is provided on the drill boom assembly 114 and configured to supply a hydraulic fluid to the drill rotation actuator 124 and the drill thrust actuator 128. In an aspect of the present disclosure, the main control valve 130 may be configured to preset an upper thrust pressure value and an upper rotation pressure value associated with the drill thrust actuator 128 and the drill rotation actuator 124. Further, the drill boom assembly 114 may include a fast feed diversion actuator 132 configured to control a flow rate of pressurized hydraulic fluid to the drill thrust actuator 128. Furthermore, the drill boom assembly 114 may include a feed/rotation control actuator 134 configured to control a supply pressure to the drill rotation actuator 124 and the drill thrust actuator 128. The drill boom assembly 114 may also include a fast feed control actuator (not shown) configured to provide a movement of the drill assembly 122 when the drill bit or a bolt is desired to move fast to reach upto a roof for drilling and bolting operations. In an exemplary embodiment of the present disclosure, the fast feed diversion actuator 132, the feed/rotation control actuator 134 and the fast feed control actuator may be positioned within the drill boom assembly 114 such that they are easily accessible by an operator standing on an operator platform 136. The fast feed diversion actuator 132, the feed/rotation control actuator 134 and the fast feed control actuator may be implemented using control stick and lever.
In an aspect of the present disclosure, a remote regulator 138 (hereinafter referred to as regulator 138) may be provided in the drill boom assembly 114 and configured to control the operation of the drill thrust actuator 128 and the drill rotation actuator 124. In an exemplary embodiment, the regulator 138 may be configured to regulate a drill speed, a thrust pressure and a rotation pressure by controlling the flow rate of the pressurized hydraulic fluid and the supply pressure to the drill rotation actuator 124 and the drill thrust actuator 128, respectively. The regulator 138 may facilitate the operator to control the operation of the drill rotation actuator 124 and the drill thrust actuator 128 based on a bolting operation, or drilling operation.
Moreover, the fast feed diversion actuator 132 is provided to control the flow rate of the pressurized hydraulic fluid to the drill thrust actuator 128 and control the movement of the drill assembly 122. The fast feed diversion actuator 132 is hydraulically coupled to the second conduit 206 to selectively increase the flow rate to the drill thrust actuator 128 by supplying the fluid flow via a fourth conduit 212.
In an aspect of the present disclosure, the regulator 138 is hydraulically coupled to the main control valve 130 to control the flow rate of the pressurized hydraulic fluid and the supply pressure to the drill thrust actuator 128 and the drill rotation actuator 124. As shown in
As shown in
For example, the first three-way valve 402 may be set at a first position by using the first input device 304 to actuate the first pressure relief cartridge 406 which provides the thrust settings for drilling operations to the drill thrust actuator 128. Therefore, if the drill assembly 122 performs drilling operation, corresponding thrust required for the drill thrust actuator 128 may be provided by actuating the first pressure relief cartridge 406. Similarly, the first three-way valve 402 may be set at a second position by using the first input device 304 to actuate the second pressure relief cartridge 408 to provide rib drill thrust settings for bolting operations to the drill thrust actuator 128. If the drill assembly 122 performs bolting operation, then the corresponding thrust required for the drill thrust actuator 128 is different from the thrust required for drilling operations, which is provided by actuating the second pressure relief cartridge 408.
In an aspect of the present disclosure, the second input device 306 may be associated with a second three-way valve 410. The second three-way valve 410 may be further connected to a second pressure relief unit 412 having a third pressure relief cartridge 414 and a fourth pressure relief cartridge 416. The second three-way valve 410 is configured to selectively actuate at least one of the third pressure relief cartridge 414 and the fourth pressure relief cartridge 416. The second pressure relief unit 412 may be configured to selectively allow the hydraulic fluid to pass to the drill rotation actuator 124 based on the selective actuation of the third pressure relief cartridge 414 or the fourth pressure relief cartridge 416.
The third pressure relief cartridge 414 may be configured to provide a first pressure relief for the drill rotation actuator 124 by limiting the rotation pilot pressure RP corresponding to a drilling torque required for drilling operations of the machine 100. Further, the fourth pressure relief cartridge 416 may be configured to provide a second pressure relief for the drill rotation actuator 124 by limiting the rotation pilot pressure RP corresponding to a bolting torque required for bolting operations of the machine 100.
In an aspect of the present disclosure, the regulator 138 may further include a flow control valve 418 associated with the third input device 308. The flow control valve 418 is configured to selectively adjust a flow of the hydraulic fluid to the drill rotation actuator 124. In an exemplary embodiment, the flow control valve 418 is configured to be adjusted corresponding to the required adjustment in the drill rotational speed based on whether the drill assembly 122 is performing a drilling function or a bolting function. Furthermore, the flow of the hydraulic fluid to the drill rotation actuator 124 may be adjusted to regulate the rotational speed of the drill bit for the drilling operations and for the bolting operations.
In an aspect of the present disclosure, based on the settings set by using the regulator 138, pressure signals from the main control valve 130 to the drill thrust actuator 128 and the drill rotation actuator 124 may be regulated and/or controlled. As explained previously, the pressure to the drill thrust actuator 128 and the drill rotation actuator 124 may be controlled based on the desired function such as the drilling operation and/or the bolting operation performed by the drill assembly 122.
The industrial applicability of the remote regulator 138 for the roof bolter 100 described herein will be readily appreciated from the foregoing discussion.
Roof bolter machines are generally used in mining industry for securing mine roofs to be self supportive. Generally, there may be two types of operations that the roof bolters perform, namely, drilling operations and bolting operations. The drilling operations include drilling the roof directly and bolting operations include inserting conventional bolts, cable bolts, or resin roof bolts and subsequently tightening of the inserted bolts.
An operator of the roof bolter may need to change drill speed, rotation pressure and thrust pressure based on a number of factors. The factors may include type of operation being performed, material being drilled, hardness of the material etc. For example, for drilling type operation, the drilling thrust required may be greater than that required for bolting operations. Similarly, for a hard material being drilled, the required drill speed, rotation pressure and thrust pressure may be higher than that for a soft material. Conventionally, separate multiple hydraulic valves are used to control the drill speed, rotation pressure and thrust pressure of the roof bolter. This is very inconvenient and cumbersome.
The remote regulator 138 of the present disclosure, eliminates the separate multiple hydraulic valves for regulating the drill speed, thrust pressure and rotation pressure for the various operations of the roof bolter machine 100. In an aspect of the present disclosure, the remote regulator 138 is provided on each side of the drill boom assembly 114 to facilitate the operator on either sides of the machine 100 to control the drill speed, thrust pressure and rotation pressure from the same location by using the remote regulator 138. Moreover, the remote regulator 138 is convenient, easy to manufacture and cost effective.
Further, using the main control valve 130, an upper limit of the thrust pressure and an upper limit of the rotation pressure may be preset. Further, using the remote regulator 138, the operator of the machine 100 may further regulate the thrust pressure to the drill thrust actuator 128 and the rotation pressure to the drill rotation actuator 124 within the preset upper limits of the thrust pressure and the rotation pressure.
In an aspect of the present disclosure, the first input device 304 may pushed inwards to selectively actuate the first pressure relief cartridge 406 for providing the drilling thrust to the drill thrust actuator 128 for drilling operation. The first input device 304 may be pulled outward to selectively actuate the second pressure relief cartridge 408 for providing rib drill thrust to the drill thrust actuator 128 for bolting operations.
Further, the second input device 306 may be pushed inwards to selectively actuate the third pressure relief cartridge 414 for providing the drilling torque to the drill rotation actuator 124 for drilling operations. Similarly, the second input device 306 may be pulled outwards to selectively actuate the fourth pressure relief cartridge 416 for providing bolting torque to the drill rotation actuator 124 for bolting operations.
Furthermore, the third input device 308 may be used by the operator to regulate the drill speed by rotating the knob either clockwise or counterclockwise. For example, the operator may turn the knob 308 in a clockwise direction to increase the drill speed and in a counterclockwise direction to decrease the drill speed, and vice-versa.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.
