A load-sensitive hydraulic drive self-adaptive drilling stepless speed regulation system

Abstract

The present invention provides a load-sensitive hydraulic drive adaptive drilling stepless speed regulation system, comprising: a low-pressure rapid feed circuit, a high-pressure stepless speed regulation circuit, and a drill rig rapid retraction circuit; and the three circuits share a load-sensitive multi-way valve, a pressure reducing valve, an oil cylinder, and a set of load-sensitive hydraulic pumps, motors, and oil tanks for inlet and return oil; the load-sensitive multi-way valve is used to realize the switching of the extended and retracted states of the oil cylinder; the pressure reducing valve is used to control the connection of the low-pressure rapid feed circuit, the high-pressure stepless speed regulation circuit, or the drill rig rapid retraction circuit according to the load end pressure. The present invention realizes adaptive drilling stepless speed regulation by switching different oil circuits through the change of the load end pressure of the load-sensitive multi-way valve. The whole adjustment process can achieve automatic switching without manual intervention, which can improve the drilling efficiency, protect the drill pipe and drill bit at the same time, and does not require the participation of sensors and control programs, making it more suitable for operation in humid environments such as underground mines.

Description

Technical Field

[0001] The present invention relates to the field of adaptive drilling, and particularly to a load-sensitive hydraulic-driven adaptive drilling stepless speed regulation system. Background Art

[0002] In the operation of mine bolt support, drilling operations need to be carried out at the support position. However, due to the dynamic non-linear change characteristics of the hardness of coal and rock, the drilling pressure fluctuates greatly during the support process. Currently, the mainstream bolt support drilling rigs generally adopt hydraulic drive, but the drilling pressure control method mainly relies on manual adjustment, that is, the operator judges the pressure change according to experience and manually adjusts the speed control valve to control the drilling speed. However, this method has obvious deficiencies. When the hardness of coal and rock is low, a small drilling pressure combined with a low speed will significantly reduce the support efficiency; when the hardness of coal and rock is high, the combination of high drilling pressure and high speed may cause damage to drill pipes or drill bits, and even pose a safety threat to operators.

[0003] Some existing adaptive drilling methods on the market usually rely on an electronic control system to achieve pressure monitoring and speed control. However, in the actual working scenario, the humid environment underground will seriously affect the performance of electronic components, and the maintenance cost is too high. At the same time, the existing adaptive drilling methods usually only have 2 or 3 speed regulation gears, that is, the speed regulation is a stepped regulation, and its control smoothness is poor, and the control result is not ideal. Summary of the Invention

[0004] In order to solve the above technical problems or at least partially solve the above technical problems, the present disclosure provides a load-sensitive hydraulic-driven adaptive drilling stepless speed regulation system.

[0005] The present disclosure provides a load-sensitive hydraulic drive self-adaptive drilling stepless speed regulation system, including: a low-pressure rapid feed circuit, a high-pressure stepless speed regulation circuit, and a drilling rig rapid retraction circuit; and the three circuits share a load-sensitive multi-way valve, a pressure reducing valve, an oil cylinder, and a group of load-sensitive hydraulic pumps, motors, and oil tanks for inlet and return oil; the load-sensitive multi-way valve is used to realize the switching of the extending and retracting states of the oil cylinder; the pressure reducing valve is used to control the connection of the low-pressure rapid feed circuit, the high-pressure stepless speed regulation circuit, or the drilling rig rapid retraction circuit according to the load end pressure; when the load-sensitive multi-way valve is in the oil cylinder extending position and the load end pressure is lower than the preset pressure threshold, the low-pressure rapid feed circuit is connected, and this circuit forms a hydraulic differential circuit, and the drilling speed of the drilling rig is fast and the drilling force is small under the low-pressure rapid feed circuit; when the load-sensitive multi-way valve is in the oil cylinder extending position and the load end pressure is higher than or equal to the preset pressure threshold, the high-pressure stepless speed regulation circuit is connected, and this circuit forms a hydraulic circuit combining a common circuit and a differential circuit, and under the high-pressure stepless speed regulation circuit, as the load end pressure increases, the feed speed of the drilling rig gradually decreases and the feed force gradually increases; when the drilling is completed and the load-sensitive multi-way valve is in the oil cylinder retracting position, the drilling rig rapid retraction circuit is connected, and due to the area difference between the two chambers of the oil cylinder, the speed of the oil cylinder during retraction is greater than the speed during slow feed, and the drilling rig rapidly retracts.

[0006] Optionally, the pressure reducing valve performs pressure conversion on the load end pressure according to a preset pressure reduction ratio, and controls the connection of the low-pressure rapid feed circuit, the high-pressure stepless speed regulation circuit, or the drilling rig rapid retraction circuit according to the pressure of the converted pressure oil.

[0007] Optionally, the low-pressure rapid feed circuit includes: a first hydraulic control multi-way valve, a pressure reducing valve; when the load end pressure is lower than the preset pressure threshold, the control oil passes through the pressure reducing valve to convert the load end pressure into a first pushing pressure, and the first pushing pressure controls the movement of the spool of the first hydraulic control multi-way valve. At this time, the first hydraulic control multi-way valve is connected, and the pressure oil passes through the load-sensitive multi-way valve, flows through the first hydraulic control multi-way valve, and flows into the oil cylinder. At this time, this circuit forms a hydraulic differential circuit.

[0008] Optionally, it further includes: a first check valve; the first check valve is connected in series in the oil circuit where the first hydraulic control multi-way valve is located, and is used to control the flow direction of the pressure oil in the low-pressure rapid feed circuit.

[0009] Optionally, a high-pressure stepless speed regulation circuit includes: a first hydraulic control multi-way valve, a second hydraulic control multi-way valve, and a pressure reducing valve; when the pressure at the load end is higher than or equal to a preset pressure threshold, the pressure oil passes through the pressure reducing valve to convert the pressure at the load end into a second pushing pressure, and the spool of the first hydraulic control multi-way valve is controlled according to the second pushing pressure. At this time, the first hydraulic control multi-way valve forms a variable throttle orifice with the change of the second pushing pressure. At the same time, the second pushing pressure controls the spool of the second hydraulic control multi-way valve, so that the pressure oil flows into the oil cylinder through the load-sensing multi-way valve, and the return oil of the oil cylinder reaches the load-sensing multi-way valve through the second hydraulic control multi-way valve. At this time, the circuit forms a hydraulic circuit combining a normal circuit and a differential circuit.

[0010] Optionally, a rapid retraction circuit of the drill rig includes: a second check valve; when the drilling is completed and the load-sensing multi-way valve is in the oil cylinder retraction position, the pressure at the load end is less than the preset pressure threshold. At this time, the pressure oil passes through the load-sensing multi-way valve and the second check valve and flows into the oil cylinder, and the return oil of the oil cylinder flows into the fuel tank through the load-sensing multi-way valve.

[0011] Optionally, it further includes: a relief valve; the relief valve is connected to the first hydraulic control multi-way valve and the second hydraulic control multi-way valve, and is used for pressure protection of the control oil circuits of the first hydraulic control multi-way valve and the second hydraulic control multi-way valve.

[0012] Optionally, it includes: a control valve group; the control valve group has five oil circuit interfaces. The A9 port of the control valve group is connected to the A10 port of the oil cylinder, the B9 port of the control valve group is connected to the B10 port of the oil cylinder, the Y port of the control valve group is connected to the B2 port of the pressure reducing valve, the A3 port of the control valve group is connected to the A1 port of the load-sensing multi-way valve, and the B3 port of the control valve group is connected to the B1 port of the load-sensing multi-way valve; the control valve group integrates a first hydraulic control multi-way valve, a second hydraulic control multi-way valve, a relief valve, a first check valve, and a second check valve.

[0013] Optionally, the connection mode of each control valve in the control valve group is as follows: the B8 port of the first check valve is connected to the A7 port of the first-state hydraulic control multi-way valve, the B7 port of the first-state hydraulic control multi-way valve is connected to the A6 port of the second-state hydraulic control multi-way valve and the A5 port of the second check valve, and the B5 port of the second check valve is connected to the B6 port of the second-state hydraulic control multi-way valve; the A4 port of the relief valve is connected to the D1 port of the first-state hydraulic control multi-way valve and the D2 port of the second-state hydraulic control multi-way valve; the A9 port and the A3 port of the control valve group are connected to the A8 port of the first check valve, the B9 port of the control valve group is connected to the B7 port of the first-state hydraulic control multi-way valve, the A6 port of the second-state hydraulic control multi-way valve, and the A5 port of the second check valve, the B3 port of the control valve group is connected to the B5 port of the second check valve and the B6 port of the second-state hydraulic control multi-way valve, and the Y port of the control valve group is connected to the A4 port of the relief valve, the D1 port of the first-state hydraulic control multi-way valve, and the D2 port of the second-state hydraulic control multi-way valve.

[0014] Optionally, the connection mode of the system is as follows: Port A9 of the control valve group is connected to Port A10 of the oil cylinder, Port B9 of the control valve group is connected to Port B10 of the oil cylinder, Port A3 of the control valve group is connected to Port A1 of the load-sensitive multi-way valve, Port B3 of the control valve group is connected to Port B1 of the load-sensitive multi-way valve, Port Y of the control valve group is connected to Port X of the load-sensitive hydraulic pump and Port LS of the load-sensitive multi-way valve, Port P of the load-sensitive hydraulic pump is connected to Port P1 of the load-sensitive multi-way valve, Port C of the load-sensitive hydraulic pump is connected to the fuel tank, Port R1 of the load-sensitive multi-way valve is connected to the fuel tank, and the motor is connected to the load-sensitive hydraulic pump.

[0015] The technical solutions provided by the embodiments of the present disclosure have the following advantages compared with the prior art:

[0016] The present invention provides a load-sensitive hydraulic drive adaptive drilling stepless speed regulation system, including: a low-pressure rapid feed circuit, a high-pressure stepless speed regulation circuit, and a drilling rig rapid retraction circuit; and the three circuits share a load-sensitive multi-way valve, a pressure reducing valve, an oil cylinder, and a set of load-sensitive hydraulic pumps, a motor, and a fuel tank for inlet and return oil; the load-sensitive multi-way valve is used to realize the switching of the extending and retracting states of the oil cylinder; the pressure reducing valve is used to control the connection of the low-pressure rapid feed circuit, the high-pressure stepless speed regulation circuit, or the drilling rig rapid retraction circuit according to the load end pressure; when the load-sensitive multi-way valve is in the oil cylinder extending position and the load end pressure is lower than the preset pressure threshold, the low-pressure rapid feed circuit is connected, and this circuit forms a hydraulic differential circuit, and the drilling speed of the drilling rig is fast and the drilling force is small under the low-pressure rapid feed circuit; when the load-sensitive multi-way valve is in the oil cylinder extending position and the load end pressure is higher than or equal to the preset pressure threshold, the high-pressure stepless speed regulation circuit is connected, and this circuit forms a hydraulic circuit combining a common circuit and a differential circuit, and under the high-pressure stepless speed regulation circuit, as the load end pressure increases, the feed speed of the drilling rig gradually decreases and the feed force gradually increases; when the drilling is completed and the load-sensitive multi-way valve is in the oil cylinder retracting position, the drilling rig rapid retraction circuit is connected, and due to the area difference between the two chambers of the oil cylinder, the speed of the oil cylinder retracting is greater than the speed during slow feed, and the drilling rig rapidly retracts. The present invention realizes the adaptive drilling stepless speed regulation by switching different oil circuits according to the change of the load end pressure of the load-sensitive multi-way valve. The whole adjustment process can be automatically switched without manual intervention, which can improve the drilling efficiency, protect the drill pipe and drill bit at the same time, and does not require the participation of sensors and control programs, and is more suitable for operation in humid environments such as underground. Description of the Drawings

[0017] The drawings here are incorporated into the specification and form a part of this specification, showing the embodiments consistent with the present disclosure, and are used together with the specification to explain the principles of the present disclosure.

[0018] To more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 This is the schematic diagram of the load-sensitive hydraulic drive self-adaptive drilling stepless speed regulation system according to the embodiment of the present invention.

[0020] In the figure: 1 - oil cylinder; 2.1 - first one-way valve; 2.2 - second one-way valve; 3 - first hydraulic control multi-way valve; 4 - control valve group; 5 - overflow valve; 6 - second hydraulic control multi-way valve; 7 - load-sensitive multi-way valve; 8 - pressure reducing valve; 9 - load-sensitive hydraulic pump; 10 - motor; 11 - oil tank. Detailed implementation manners

[0021] Combined with the accompanying drawings in the embodiments of the present invention, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other implementation manners obtained by those of ordinary skill in the art without creative efforts belong to the scope protected by the present invention.

[0022] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those who are familiar with this technology to understand and read, and are not used to limit the limiting conditions under which the present invention can be implemented. Therefore, they do not have technical essential significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should fall within the scope covered by the technical content disclosed in the present invention. It should be noted that in this specification, relational terms such as "first" and "second" are only used to distinguish one entity from several other entities, and do not necessarily require or imply any actual relationship or order between these entities.

[0023] The present invention provides an embodiment:

[0024] As Figure 1As shown in the figure, a load-sensitive hydraulic drive adaptive drilling stepless speed regulation system includes: a low-pressure rapid feed circuit, a high-pressure stepless speed regulation circuit, and a rapid retraction circuit for the drilling rig; and the three circuits share a load-sensitive multi-way valve 7, a pressure reducing valve 8, a hydraulic cylinder 1, and a group of load-sensitive hydraulic pumps 9, a motor 10, and a fuel tank 11 for inlet and return oil; the load-sensitive multi-way valve 7 is used to switch the extension and retraction states of the hydraulic cylinder 1; the pressure reducing valve 8 is used to control the connection of the low-pressure rapid feed circuit, the high-pressure stepless speed regulation circuit, or the rapid retraction circuit for the drilling rig according to the load end pressure; when the load-sensitive multi-way valve 7 is in the extended position of the hydraulic cylinder 1 and the load end pressure is lower than the preset pressure threshold, the low-pressure rapid feed circuit is connected, and this circuit forms a hydraulic differential circuit. In the low-pressure rapid feed circuit, the drilling speed of the drilling rig is fast and the drilling force is small; when the load-sensitive multi-way valve 7 is in the extended position of the hydraulic cylinder 1 and the load end pressure is higher than or equal to the preset pressure threshold, the high-pressure stepless speed regulation circuit is connected, and this circuit forms a hydraulic circuit combining a normal circuit and a differential circuit. In the high-pressure stepless speed regulation circuit, as the load end pressure increases, the feed speed of the drilling rig gradually decreases and the feed force gradually increases; when the drilling is completed and the load-sensitive multi-way valve 7 is in the retracted position of the hydraulic cylinder 1, the rapid retraction circuit for the drilling rig is connected. Due to the area difference between the two chambers of the hydraulic cylinder 1, the speed of the hydraulic cylinder 1 during retraction is greater than the speed during slow feed, and the drilling rig quickly retracts.

[0025] In this embodiment, the pressure reducing valve 8 performs pressure conversion on the load end pressure according to a preset pressure reduction ratio, and controls the connection of the low-pressure rapid feed circuit, the high-pressure stepless speed regulation circuit, or the rapid retraction circuit for the drilling rig according to the pressure of the converted pressure oil.

[0026] In this embodiment, it further includes: a first one-way valve 2.1; the first one-way valve 2.1 is connected in series in the oil circuit where the first hydraulic control multi-way valve 3 is located, and is used to control the flow direction of the pressure oil in the low-pressure rapid feed circuit.

[0027] In this embodiment, it further includes: a relief valve 5; the relief valve 5 is connected to the first hydraulic control multi-way valve 3 and the second hydraulic control multi-way valve 6, and is used for pressure protection of the control oil circuits of the first hydraulic control multi-way valve 3 and the second hydraulic control multi-way valve 6.

[0028] In this embodiment, a control valve group 4; the control valve group 4 has five oil circuit interfaces. The A9 port of the control valve group 4 is connected to the A10 port of the hydraulic cylinder 1, the B9 port of the control valve group 4 is connected to the B10 port of the hydraulic cylinder 1, the Y port of the control valve group 4 is connected to the B2 port of the pressure reducing valve 8, the A3 port of the control valve group 4 is connected to the A1 port of the load-sensitive multi-way valve 7, and the B3 port of the control valve group 4 is connected to the B1 port of the load-sensitive multi-way valve 7; the control valve group 4 integrates a first hydraulic control multi-way valve 3, a second hydraulic control multi-way valve 6, a relief valve 5, a first one-way valve 2.1, and a second one-way valve 2.2.

[0029] In this embodiment, the connection mode of each control valve in the control valve group 4 is as follows: the B8 port of the first check valve 2.1 is connected to the A7 port of the first-state hydraulically controlled multi-way valve; the B7 port of the first-state hydraulically controlled multi-way valve is connected to the A6 port of the second-state hydraulically controlled multi-way valve and the A5 port of the second check valve 2.2; the B5 port of the second check valve 2.2 is connected to the B6 port of the second-state hydraulically controlled multi-way valve; the A4 port of the relief valve 5 is connected to the D1 port of the first-state hydraulically controlled multi-way valve and the D2 port of the second-state hydraulically controlled multi-way valve; the A9 port and the A3 port of the control valve group 4 are connected to the A8 port of the first check valve 2.1; the B9 port of the control valve group 4 is connected to the B7 port of the first-state hydraulically controlled multi-way valve, the A6 port of the second-state hydraulically controlled multi-way valve, and the A5 port of the second check valve 2.2; the B3 port of the control valve group 4 is connected to the B5 port of the second check valve 2.2 and the B6 port of the second-state hydraulically controlled multi-way valve; the Y port of the control valve group 4 is connected to the A4 port of the relief valve 5, the D1 port of the first-state hydraulically controlled multi-way valve, and the D2 port of the second-state hydraulically controlled multi-way valve.

[0030] In this embodiment, the connection mode of the system is as follows: the A9 port of the control valve group 4 is connected to the A10 port of the oil cylinder 1; the B9 port of the control valve group 4 is connected to the B10 port of the oil cylinder 1; the A3 port of the control valve group 4 is connected to the A1 port of the load-sensing multi-way valve 7; the B3 port of the control valve group 4 is connected to the B1 port of the load-sensing multi-way valve 7; the Y port of the control valve group 4 is connected to the X port of the load-sensing hydraulic pump 9 and the LS port of the load-sensing multi-way valve 7; the P port of the load-sensing hydraulic pump 9 is connected to the P1 port of the load-sensing multi-way valve 7; the C port of the load-sensing hydraulic pump 9 is connected to the fuel tank 11; the R1 port of the load-sensing multi-way valve 7 is connected to the fuel tank 11; the motor 10 is connected to the load-sensing hydraulic pump 9; the A2 port of the pressure reducing valve 8 is connected to the X port of the load-sensing hydraulic pump 9 and the LS port of the load-sensing multi-way valve 7; the B2 port of the pressure reducing valve 8 is connected to the control valve group 4.

[0031] In this embodiment, the low-pressure rapid feed circuit includes: a first hydraulically controlled multi-way valve 3 and a pressure reducing valve 8. When the load end pressure is lower than the preset pressure threshold, the control oil passes through the pressure reducing valve 8 to convert the load end pressure into a first pushing pressure, and the first pushing pressure controls the spool movement of the first hydraulically controlled multi-way valve 3. At this time, the first hydraulically controlled multi-way valve 3 is connected, and the pressure oil passes through the load-sensing multi-way valve 7, flows through the first hydraulically controlled multi-way valve 3, and flows into the oil cylinder 1. At this time, this circuit forms a hydraulic differential circuit.

[0032] In this embodiment, the high-pressure stepless speed regulation circuit includes: a first hydraulic control multi-way valve 3, a second hydraulic control multi-way valve 6, and a pressure reducing valve 8; when the pressure at the load end is higher than or equal to the preset pressure threshold, the pressure oil passes through the pressure reducing valve 8 to convert the pressure at the load end into a second pushing pressure, and the spool of the first hydraulic control multi-way valve 3 is controlled to act according to the second pushing pressure. At this time, the first hydraulic control multi-way valve 3 forms a variable throttle orifice along with the change of the second pushing pressure. At the same time, the second pushing pressure controls the spool of the second hydraulic control multi-way valve 6, so that the pressure oil flows into the oil cylinder 1 through the load sensing multi-way valve 7, and the oil return of the oil cylinder 1 reaches the load sensing multi-way valve 7 through the second hydraulic control multi-way valve 6. At this time, this circuit forms a hydraulic circuit combining a normal circuit and a differential circuit.

[0033] In this embodiment, the rapid retraction circuit of the drill rig includes: a second one-way valve 2.2; when the drilling is completed and the load sensing multi-way valve 7 is in the retracted position of the oil cylinder 1, the pressure at the load end is less than the preset pressure threshold. At this time, the pressure oil passes through the load sensing multi-way valve 7, through the second one-way valve 2.2, and flows into the oil cylinder 1, and the oil return of the oil cylinder 1 flows into the oil tank 11 through the load sensing multi-way valve 7.

[0034] Working principle:

[0035] According to Figure 1 The system is built according to the schematic diagram of the load-sensing hydraulic drive adaptive drilling stepless speed regulation system shown. The A10 port of the oil cylinder 1 and the A9 port of the control valve group 4 are connected by a rubber hose, and the B10 port of the oil cylinder 1 and the B9 port of the control valve group 4 are connected by a rubber hose. The P port of the load-sensing hydraulic pump 9 and the P1 port of the load-sensing multi-way valve 7 are connected by a rubber hose, the C port of the load-sensing hydraulic pump 9 is connected to the oil tank 11 by a rubber hose, the X port of the load-sensing hydraulic pump 9 is connected to the LS port of the load-sensing multi-way valve 7 and the A2 port of the pressure reducing valve 8 by a rubber hose, and the B2 port of the pressure reducing valve 8 and the Y port of the control valve group 4 are connected by a rubber hose. The R1 port of the load-sensing multi-way valve 7 and the oil tank 11 are connected by a rubber hose, the A1 port of the load-sensing multi-way valve 7 and the A3 port of the control valve group 4 are connected by a rubber hose, the B1 port of the load-sensing multi-way valve 7 and the B3 port of the control valve group 4 are connected by a rubber hose, the A8 port of the first one-way valve 2.1 and the A9 port and A3 port of the control valve group 4 are connected by a rubber hose; the B8 port of the first one-way valve 2.1 and the A7 port of the first hydraulic control multi-way valve 3 are connected by a rubber hose; the B7 port of the first hydraulic control multi-way valve 3 and the B9 port of the control valve group 4, the A6 port of the second hydraulic control multi-way valve 6, and the A5 port of the second one-way valve 2.2 are connected by a rubber hose; the B5 port of the second one-way valve 2.2 and the B6 port of the second hydraulic control multi-way valve 6 and the B3 port of the control valve group 4 are connected by a rubber hose; the A4 port of the relief valve 5 and the Y port of the control valve group 4, the D1 port of the first hydraulic control multi-way valve 3, and the D2 port of the second hydraulic control multi-way valve 6 are connected by a rubber hose, and the B4 port of the relief valve 5 is connected to the oil tank 11 by a rubber hose, and it is ensured that there is no abnormal situation of liquid leakage in the system.

[0036] At the beginning of drilling, the load-sensitive multi-way valve 7 is controlled to switch to the left working position, so that the oil cylinder 1 enters the extending working stage, that is, the drill box feeding stage.

[0037] When encountering a working condition with relatively soft coal and rock, and the load end pressure at the LS end of the control valve group 4 is lower than the preset pressure threshold, the control oil flows into the pressure reducing valve 8 from the A2 port. After the load end pressure is converted into the first pushing pressure by the pressure reducing valve 8, it flows out from the B2 port. At this time, the control oil pressure is insufficient to push the spools of the first hydraulic control multi-way valve 3 and the second hydraulic control multi-way valve 6 to move, and the two maintain the normal working state, that is, the A7 to B7 of the first hydraulic control multi-way valve 3 are fully open, and the A6 to B6 of the second hydraulic control multi-way valve 6 are fully closed. Therefore, the pressure oil drawn from the fuel tank 11 passes through the A1 of the load-sensitive multi-way valve 7, then flows through the A3 port of the control valve group 4 and the A8 and B8 ports of the first one-way valve 2.1, flows into the first hydraulic control multi-way valve 3 from the A7 port, and flows out from the B7 port. Finally, it flows into the A10 cavity and the B10 cavity of the oil cylinder 1 from the A9 port and the B9 port of the control valve group 4 at the same time. At this time, a hydraulic differential circuit is formed, and the drill box has a fast drilling speed and a small drilling force.

[0038] When encountering a working condition with relatively hard coal and rock, and the load end pressure at the LS end of the control valve group 4 is higher than or equal to the preset pressure threshold, the control oil flows into the pressure reducing valve 8 from the A2 port. After the load end pressure is converted into the second pushing pressure by the pressure reducing valve 8, it flows out from the B2 port. Due to the pressure protection of the relief valve 5, the fluctuation range of the second pushing pressure is within the range of the first pushing pressure and the preset protection pressure threshold of the relief valve 5. At this time, after the control oil flows out from the B2 port, it pushes the spool of the first hydraulic control multi-way valve 3 to act, so that the first hydraulic control multi-way valve 3 forms a variable throttle orifice that changes with the load pressure. The smaller the pressure at the B2 port, the larger the variable throttle orifice; the larger the pressure at the B2 port, the smaller the variable throttle orifice. When the pressure at the B2 port is less than or equal to the first pushing pressure, the first hydraulic control multi-way valve 3 is fully open; when the pressure at the B2 port is equal to the preset protection pressure threshold of the relief valve 5, the first hydraulic control multi-way valve 3 is fully closed. At the same time, under the action of the second pushing pressure, the control oil pushes the spool of the second hydraulic control multi-way valve 6 to act, so that the A6 and B6 of the second hydraulic control multi-way valve 6 are switched to the connected state. Therefore, the pressure oil drawn from the fuel tank 11 passes through the A1 port of the load-sensitive multi-way valve 7, reaches the A10 cavity of the oil cylinder 1 through the A9 port of the control valve group 4. The oil returning from the B10 cavity of the oil cylinder 1 flows through the B9 of the control valve group 4, the B6 of the second hydraulic control multi-way valve 6, and the B3 of the control valve group 4 to reach the B1 of the load-sensitive multi-way valve 7. At this time, a hydraulic circuit combining a normal circuit and a differential circuit is formed, that is, a variable throttle orifice is connected in parallel on the normal hydraulic circuit. As the load end pressure continuously increases, the variable throttle orifice gradually becomes smaller, and the feeding speed of the drill is gradually reduced, and the feeding force gradually becomes larger.

[0039] After the drilling is completed, the load-sensitive multi-way valve 7 is controlled to switch to the right working position, so that the oil cylinder 1 enters the retraction working stage, that is, the drill box retracts.

[0040] In the stage of the drill box retracting, at this time, the pressure at the load end is less than the preset pressure threshold, so the control oil pressure is less than the first pushing pressure. Both the first hydraulic control multi-way valve 3 and the second hydraulic control multi-way valve 6 are in the normal state, that is, the port A7 to port B7 of the first hydraulic control multi-way valve 3 are all open, and the port A6 to port B6 of the second hydraulic control multi-way valve 6 are all closed. The pressure oil pumped out from the fuel tank 11 passes through the port B1 of the load-sensitive multi-way valve 7, and flows into the B10 chamber of the oil cylinder 1 through the ports A5 and B5 of the second one-way valve 2.2. The return oil of the oil cylinder 1 reaches the port A1 of the load-sensitive multi-way valve 7 through the A10 chamber, that is, it returns to the fuel tank 11. Due to the area difference between the two chambers of the oil cylinder 1, the speed of the oil cylinder 1 during retraction is greater than the speed during slow feeding, and the working state is the rapid retraction of the drilling rig.

[0041] In this embodiment, the motor 10 controls the load-sensitive hydraulic pump 9 to pump pressure oil from the fuel tank 11.

[0042] In this embodiment, the motor 10 and the load-sensitive hydraulic pump 9 are connected by a coupling, and they can also be connected by other connection methods. The present invention is not limited thereto.

[0043] In this embodiment, the pressure reducing valve 8 is a fixed ratio pressure reducing valve 8, and the preset pressure reduction ratio is 0.25. That is, when the pressure at the load end is 20 Mpa, the control oil pressure is 5 Mpa. The pressure reducing valve 8 used in the present invention and the set pressure reduction ratio are only a preferred implementation of the present invention. Other pressure reducing valves 8 can be selected according to the actual working conditions, and the pressure reduction ratio can be adjusted by itself. It is used in combination with the control characteristics of the first hydraulic control multi-way valve 3 and the second hydraulic control multi-way valve 6. The present invention is not limited thereto.

[0044] In this embodiment, the first hydraulic control multi-way valve 3 is a normally open hydraulic control two-way valve, and its inlet and outlet ports are in a communicating state in the normal state. When the control oil pressure is greater than 5 MPa, its inlet and outlet ports are in a completely closed state; the second hydraulic control multi-way valve 6 is a normally closed hydraulic control two-way valve, and its inlet and outlet ports are in a disconnected state in the normal state. When there is a control oil pressure of more than 3 MPa, the state automatically switches to the inlet and outlet ports being connected. The present invention is set for the automatic logical switching of two hydraulic circuits, and other hydraulic control multi-way valves can also be selected. The present invention is not limited thereto.

[0045] In this embodiment, the preset pressure threshold is 10 MPa; the first pushing pressure is less than 2.5 MPa; the preset protection pressure threshold of the overflow valve 5 is 5 MPa; the second pushing pressure is greater than 2.5 MPa and less than 5 MPa. The various thresholds set in the present invention are only recommended values, and the set thresholds can be adjusted according to the actual working conditions. The present invention is not limited thereto.

[0046] In this embodiment, the load-sensitive multi-way valve 7 can also be replaced by a switching valve with load-sensitive function or a self-assembled hydraulic valve group with load feedback function, and the present invention is not limited thereto.

[0047] For the present invention, it is not limited to be applicable to the field of adaptive drilling of downhole anchor support drills, and can also be applied to other working environments that require stepless adaptive adjustment of the cylinder speed.

[0048] The above are only specific embodiments of the present disclosure, enabling those skilled in the art to understand or implement the present disclosure. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure will not be limited to these embodiments described herein, but rather will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A load-sensitive hydraulic drive self-adaptive drilling stepless speed regulation system, characterized in that Including: A low-pressure rapid feed circuit, a high-pressure stepless speed regulation circuit, and a rapid retraction circuit of the drilling rig; and the three circuits share a load-sensitive multi-way valve (7), a pressure reducing valve (8), an oil cylinder (1), and a group of load-sensitive hydraulic pumps (9), motors (10), and oil tanks (11) for inlet and return oil; The load-sensitive multi-way valve (7) is used to realize the switching of the extending and retracting states of the oil cylinder (1); the pressure reducing valve (8) is used to control the connection of the low-pressure rapid feed circuit, the high-pressure stepless speed regulation circuit, or the rapid retraction circuit of the drilling rig according to the load end pressure; When the load-sensitive multi-way valve (7) is in the extending position of the oil cylinder (1) and the load end pressure is lower than the preset pressure threshold, the low-pressure rapid feed circuit is connected, and this circuit forms a hydraulic differential circuit. Under the low-pressure rapid feed circuit, the drilling speed of the drilling rig is fast and the drilling force is small; When the load-sensitive multi-way valve (7) is in the extending position of the oil cylinder (1) and the load end pressure is higher than or equal to the preset pressure threshold, the high-pressure stepless speed regulation circuit is connected, and this circuit forms a hydraulic circuit combined with a common circuit and a differential circuit. Under the high-pressure stepless speed regulation circuit, as the load end pressure increases, the feed speed of the drilling rig gradually decreases and the feeding force gradually increases; When the drilling is completed and the load-sensitive multi-way valve (7) is in the retracting position of the oil cylinder (1), the rapid retraction circuit of the drilling rig is connected. Due to the area difference between the two chambers of the oil cylinder (1), the speed of the oil cylinder (1) during retraction is greater than that during slow feeding, and the drilling rig retracts rapidly; The low-pressure rapid feed circuit includes: a first hydraulic control multi-way valve (3), a pressure reducing valve (8); When the load end pressure is lower than the preset pressure threshold, the control oil passes through the pressure reducing valve (8) to convert the load end pressure into a first pushing pressure, and the first pushing pressure controls the movement of the spool of the first hydraulic control multi-way valve (3). At this time, the first hydraulic control multi-way valve (3) is connected, and the pressure oil passes through the load-sensitive multi-way valve (7), flows through the first hydraulic control multi-way valve (3), and flows into the oil cylinder (1). At this time, this circuit forms a hydraulic differential circuit; The high-pressure stepless speed regulation circuit includes: a first hydraulic control multi-way valve (3), a second hydraulic control multi-way valve (6), a pressure reducing valve (8); When the load end pressure is higher than or equal to the preset pressure threshold, the pressure oil passes through the pressure reducing valve (8) to convert the load end pressure into a second pushing pressure. According to the second pushing pressure, the movement of the spool of the first hydraulic control multi-way valve (3) is controlled. At this time, the first hydraulic control multi-way valve (3) forms a variable throttle orifice with the change of the second pushing pressure. At the same time, the second pushing pressure controls the movement of the spool of the second hydraulic control multi-way valve (6), so that the pressure oil passes through the load-sensitive multi-way valve (7) and flows into the oil cylinder (1). The return oil of the oil cylinder (1) reaches the load-sensitive multi-way valve (7) through the second hydraulic control multi-way valve (6). At this time, this circuit forms a hydraulic circuit combined with a common circuit and a differential circuit; The rapid retraction circuit of the drilling rig includes: a second one-way valve (2.2); When the drilling is completed and the load-sensitive multi-way valve (7) is in the retracting position of the oil cylinder (1), the load end pressure is less than the preset pressure threshold. At this time, the pressure oil passes through the load-sensitive multi-way valve (7), passes through the second one-way valve (2.2), and flows into the oil cylinder (1). The return oil of the oil cylinder (1) passes through the load-sensitive multi-way valve (7) and flows into the oil tank (11).

2. The load-sensitive hydraulic drive adaptive drilling stepless speed regulation system according to claim 1, wherein The pressure reducing valve (8) performs pressure conversion on the pressure at the load end according to a preset pressure reduction ratio, and controls the connection of the low-pressure rapid feed circuit, the high-pressure stepless speed regulation circuit, or the rapid retraction circuit of the drilling rig according to the pressure of the converted pressure oil.

3. A load-sensitive hydraulic drive adaptive drilling stepless speed regulation system according to claim 1, characterized in that, It further includes: A first one-way valve (2.1); The first one-way valve (2.1) is connected in series in the oil circuit where the first hydraulically controlled multi-way valve (3) is located, and is used to control the flow direction of the pressure oil in the low-pressure rapid feed circuit.

4. A load-sensitive hydraulic drive adaptive drilling stepless speed regulation system according to any one of claims 1-3, characterized in that, It further includes: A relief valve (5); The relief valve (5) is connected to the first hydraulically controlled multi-way valve (3) and the second hydraulically controlled multi-way valve (6), and is used for pressure protection of the control oil circuits of the first hydraulically controlled multi-way valve (3) and the second hydraulically controlled multi-way valve (6).

5. A load-sensitive hydraulic drive adaptive drilling stepless speed regulation system according to claim 4, characterized in that, It includes a control valve group (4); The control valve group (4) has five oil circuit interfaces. The A9 port of the control valve group (4) is connected to the A10 port of the oil cylinder (1), the B9 port of the control valve group (4) is connected to the B10 port of the oil cylinder (1), the Y port of the control valve group (4) is connected to the B2 port of the pressure reducing valve (8), the A3 port of the control valve group (4) is connected to the A1 port of the load-sensing multi-way valve (7), and the B3 port of the control valve group (4) is connected to the B1 port of the load-sensing multi-way valve (7); The control valve group (4) integrates a first hydraulically controlled multi-way valve (3), a second hydraulically controlled multi-way valve (6), a relief valve (5), a first one-way valve (2.1), and a second one-way valve (2.2).

6. A load-sensitive hydraulic drive adaptive drilling stepless speed regulation system according to claim 5, characterized in that The connection mode of each control valve in the control valve group (4) is as follows: The B8 port of the first one-way valve (2.1) is connected to the A7 port of the first-state hydraulically controlled multi-way valve. The B7 port of the first-state hydraulically controlled multi-way valve is connected to the A6 port of the second-state hydraulically controlled multi-way valve and the A5 port of the second one-way valve (2.2). The B5 port of the second one-way valve (2.2) is connected to the B6 port of the second-state hydraulically controlled multi-way valve; The A4 port of the relief valve (5) is connected to the D1 port of the first-state hydraulically controlled multi-way valve and the D2 port of the second-state hydraulically controlled multi-way valve; The A9 port and the A3 port of the control valve group (4) are connected to the A8 port of the first one-way valve (2.1). The B9 port of the control valve group (4) is connected to the B7 port of the first-state hydraulically controlled multi-way valve, the A6 port of the second-state hydraulically controlled multi-way valve, and the A5 port of the second one-way valve (2.2). The B3 port of the control valve group (4) is connected to the B5 port of the second one-way valve (2.2) and the B6 port of the second-state hydraulically controlled multi-way valve. The Y port of the control valve group (4) is connected to the A4 port of the relief valve (5), the D1 port of the first-state hydraulically controlled multi-way valve, and the D2 port of the second-state hydraulically controlled multi-way valve.

7. A load-sensitive hydraulic drive adaptive drilling stepless speed regulation system according to claim 1, characterized in that The connection mode of this system is: The A9 port of the control valve group (4) is communicated with the A10 port of the oil cylinder (1), the B9 port of the control valve group (4) is communicated with the B10 port of the oil cylinder (1), the A3 port of the control valve group (4) is communicated with the A1 port of the load sensing multi-way valve (7), the B3 port of the control valve group (4) is communicated with the B1 port of the load sensing multi-way valve (7), the Y port of the control valve group (4) is communicated with the X port of the load sensing hydraulic pump (9) and the LS port of the load sensing multi-way valve (7), the P port of the load sensing hydraulic pump (9) is communicated with the P1 port of the load sensing multi-way valve (7), the C port of the load sensing hydraulic pump (9) is communicated with the oil tank (11), the R1 port of the load sensing multi-way valve (7) is communicated with the oil tank (11), and the motor (10) is connected to the load sensing hydraulic pump (9); The A2 port of the pressure reducing valve (8) is communicated with the X port of the load sensing hydraulic pump (9) and the LS port of the load sensing multi-way valve (7), and the B2 port of the pressure reducing valve (8) is communicated with the control valve group (4).

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