CN105114373A - Hydraulic control system for impact hammer of rock drilling machine - Google Patents
Hydraulic control system for impact hammer of rock drilling machine Download PDFInfo
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- CN105114373A CN105114373A CN201510473200.3A CN201510473200A CN105114373A CN 105114373 A CN105114373 A CN 105114373A CN 201510473200 A CN201510473200 A CN 201510473200A CN 105114373 A CN105114373 A CN 105114373A
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- control valve
- pressure
- percussive hammer
- hydraulic
- hammer
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Abstract
The invention discloses a hydraulic control system for an impact hammer of a rock drilling machine, and belongs to the technical field of hydraulic control. The system comprises a load sensing pump, an impact hammer control valve with a pressure sensing assembly, a hydraulic impact hammer, a motor and a hydraulic oil tank, wherein the load sensing pump is driven by the motor, and a flow control valve for stabilizing the flow output and a pressure control valve for limiting the maximum working pressure of the system are integrated to the load sensing pump; a main oil inlet of the load sensing pump is connected with a main oil inlet of the impact hammer control valve; a main oil returning port of the impact hammer control valve is connected with the oil tank; a pressure feedback port of the impact hammer control valve is connected with a control oil port of the load sensing pump; working oil ports A and B of the impact hammer control valve are correspondingly connected with the main oil returning port and the main oil inlet of the hydraulic impact hammer. Compared with the DRG remote constant pressure control scheme, the system has the advantages that the working reliability and stability can be improved, and the energy consumption can be decreased; in addition, the system is simple, and small in cost.
Description
Technical field
The present invention relates to technical field of hydraulic, especially a kind of hydraulic control system for rock drill percussive hammer.
Background technique
Rock drill percussive hammer is mainly used in the mechanized construction of method of tunnel drilling and blasting, and for realizing rock drill tunneling construction quickly and efficiently in tunnel, the rock drill percussive hammer HYDRAULIC CONTROL SYSTEM solution finding high efficient and reliable just seems particularly important.
If under rock drill percussive hammer need be made to be operated in little impact operating mode, the working pressure of rock drill percussive hammer hydraulic control system and flow need be set as 90bar and 90l/min respectively; And the large impact action of rock drill will be realized, then need system working pressure and flow to be set as 130bar and 120l/min respectively.Therefore be not difficult to find, the normal switching of large and small impact two grades of functions of rock drill percussive hammer be realized, then both needed the flow controlling to flow into rock drill percussive hammer hydraulic oil, and also needed to control its working pressure.For the low energy consumption of the large and small impact two grades of functions realizing rock drill percussive hammer normally switches, therefore not only need the flow controlling inflow rock drill hydraulic oil, also need to control its working pressure.
Producer mostly adopts the long-range Isobarically Control technological scheme of the DRG of A10VSO variable displacement pump to meet the pressure flow coupling demand of rock drill percussive hammer both at home and abroad at present, as shown in Figure 4, the throttle valve group that this system schema is made up of a long-range Isobarically Control pump of A10VSODRG, percussive hammer control bound, 5 relief valves pressure controlled valve group, 2 throttle valve form, one for monitoring the pressure gauge of surge pressure, hydraulic impact hammer, the damping hole of two 0.8mm, the hydraulic parts such as motor and fuel tank form.(11) and limit the pressure controlled valve of pump Maximum operating pressure wherein, load sensitive pump is integrated with flow control valve.
Starting electrical machinery, make A10VSODRG variable displacement pump to system fuel feeding and pull percussive hammer control bound handle to make valve element position be in working position 1. on little impact position, system working connection c after main valve by part oil by oil circuit a and through the damping hole oil sump tank of 0.8mm, another part pressure oil then flows to percussive hammer through throttle valve group makes percussive hammer produce action, for the action making percussive hammer produce little impact, the flow that flows through throttle valve 2 in throttle valve group need be regulated and the pressure tabular value being used in monitoring surge pressure is shown as 90bar, now in pressure controlled valve group, the hydraulic control mouth of valve 1 and valve 2 passes into pressure oil through oil circuit b and oil circuit a respectively and valve 1 and valve 2 is commutated, under such system is just operated in 90bar constant pressure, matching relationship when meeting the little percussion action of rock drill percussive hammer between required working pressure (90bar) and flow (90l/min is).Continuing to pull percussive hammer control bound handle makes valve element position be in working position 2. on large impact position, system oil-way all leads to rock drill percussive hammer through throttle valve group, in like manner, large impact position is operated in for making rock drill percussive hammer, the flow that flows through throttle valve group need be regulated and make manometric force value be shown as 130bar, in pressure controlled valve group, the hydraulic control mouth of valve 1 makes valve 1 commutate through oil circuit b cut-in pressure oil, and the hydraulic control mouth of valve 2 cannot commutate by making valve 2 without pressure oil because of oil circuit a, under such system is just operated in the constant pressure of 130bar, achieve the matching relationship between working pressure (130bar) needed for the action of rock drill percussive hammer large impact and flow (120l/min is).Although the program can realize the switching of the large and small percussion action of rock drill percussive hammer, system have employed more hydraulic parts, adds complexity and the fault point of system, thus reduces the reliability of system.
In addition, there is uncontrollable restriction loss at percussive hammer control bound place in DRG long-range Isobarically Control technology.When A10VSODRG variable displacement pump is to system fuel feeding and when driving percussive hammer action, in pressure controlled valve group, the set pressure Py of valve 4 or valve 5 will be carried in A10VSODRG variable displacement pump X mouth (controlling mouth/outside control mouth) place, due to the pressure reduction of flow control valve 2 both sides oil circuit control constant (namely hydraulic pump outlet and X mouth pressure reduction constant, be about about 18bar), the pressure P b that pump exports is not when higher than the pressure controlled valve 1(210bar limiting pump Maximum operating pressure) when working, be not difficult to find according to pump discharge pressure Pb formula (Pb=Py+ P), pump delivery pressure Pb will work under being in a steady state value and is not subject to load P
lthe impact of change.But according to throttle flow rate formula (q=K × A × (Pb-P
l)
k, k is flow coefficient) be not difficult to find, the flow q of input percussive hammer not only depends on the opening area A of throttle valve in throttle valve group, also with percussive hammer induced pressure P
lchange relevant, work as P
lwhen changing, the flow q of input percussive hammer also can follow change and then have impact on the stability of percussive hammer work.
If ignore the loss in efficiency of oil hydraulic pump and percussive hammer, the energy loss of DRG remote pressure control system is mainly the restriction loss at throttle valve group place, and system effectiveness is P
l/ Pb, the pressure P b exported due to pump is determined by the set pressure Py of valve 4 or valve 5 in pressure controlled valve group, and therefore the efficiency of system is primarily of percussive hammer induced pressure P
ldetermine.Work as load P
lvalue is higher close to system effectiveness during the pressure P b exported with pump, but real impact hammers induced pressure P into shape
lvalue is the value of a real-time change, as induced pressure P
lwhen value is much smaller than hydraulic pressure pumping hole delivery pressure value Pb, the working efficiency of system will along with reduction.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of hydraulic control system of rock drill percussive hammer, this system adopts the long-range Isobarically Control scheme of DRG of A10 pump relative to domestic and international producer, can improve the reliability of rock drill percussive hammer hydraulic work system, stability and reduce the energy consumption of hydraulic control system, and system is simple, with low cost.
For solving the problems of the technologies described above, the technical solution used in the present invention is: a kind of hydraulic control system of rock drill percussive hammer, it is characterized in that comprising load sensitive pump, the percussive hammer control valve of a band pressure sensor module, hydraulic impact hammer, motor and hydraulic oil container, described load sensitive pump is driven by motor, and on load sensitive pump, be integrated with the flow control valve of regime flow output and the pressure controlled valve of the system of restriction Maximum operating pressure, the main filler opening of described load sensitive pump is connected with the main filler opening of percussive hammer control valve, the main return opening of percussive hammer control valve connects fuel tank, the pressure feedback Ls(Loadsensing of percussive hammer control valve, load-sensitive) mouth is connected with the control port X mouth of load sensitive pump, actuator port A with B of percussive hammer control valve is connected with the main return opening of hydraulic impact hammer and main filler opening respectively.
Do to supplement further to said structure, described percussive hammer control valve is provided with two working positions, be respectively little impact position and large impact position, described little impact position is communicated with the secondary relief of 90 bar on percussive hammer control valve side, and large impact position is communicated with the secondary relief of 130 bar on percussive hammer control valve side.
Do to supplement further to said structure, it is 210-230 bar that described pressure controlled valve limits system Maximum operating pressure, and the hydraulic control mouth pressure reduction at flow control valve two ends is 18 bar.
Do to supplement further to said structure, described percussive hammer control valve is provided with pressure sensor module, induced pressure in this pressure sensor module monitoring system, and be fed back to the control port X mouth of load sensitive pump in real time, load-sensitive pump discharge pressure is, form equilibrium relation at flow control valve two ends like this, namely value is for constant; Be not difficult to reach a conclusion according to throttle flow rate formula, the output flow of percussive hammer control valve
qonly depend on the opening area of flow control valve, and have nothing to do with load variations thus ensure that the stability of system works; The energy loss of this system mainly comes from the restriction loss in percussive hammer control valve place, and its energy loss is, because value is less, therefore the restriction loss at series flow control valve place is also less, and the low energy consumption achieving percussive hammer controls.
The beneficial effect adopting technique scheme to produce is: the present invention is compared with present hydraulic control system, its structure composition wants simple, decrease the hydraulic parts that some are unnecessary, such as throttle valve group and pressure controlled valve group etc., the output flow and the load that achieve percussive hammer control valve have nothing to do, thus improve the reliability and stability of hydraulic control system.In addition, it is little that this system control scheme controls the restriction loss at valve port place compared to traditional scheme, therefore, this system significantly reduce energy consumption.
Accompanying drawing explanation
Below in conjunction with the drawings and specific embodiments, the present invention is further detailed explanation.
Fig. 1 is hydraulic control system scheme of the present invention;
Fig. 2 is the graphic symbol of percussive hammer control valve in Fig. 1;
Fig. 3 is the graphic symbol of load sensitive pump in Fig. 1;
Fig. 4 is the stoste pressure control system scheme of rock drill percussive hammer;
Fig. 5 is the characteristic working curve of oil hydraulic pump;
Wherein: 1, load sensitive pump, 2, percussive hammer control valve, 3, hydraulic impact hammer, 4, motor, 5, hydraulic oil container, 6, pressure controlled valve group, 7, pressure gauge, 8, damping hole, 9, throttle valve group, 11, flow control valve, 12, pressure controlled valve.
Embodiment
1-3 is known with reference to the accompanying drawings, the present invention is specifically related to a kind of hydraulic control system of rock drill percussive hammer, this system comprises load sensitive pump 1, the percussive hammer control valve 2 of a band pressure sensor module, hydraulic impact hammer 3, motor 4 and hydraulic oil container 5, load sensitive pump 1 is driven by motor 4, and on load sensitive pump 1, be integrated with the flow control valve 11 of regime flow output and the pressure controlled valve 12 of the system of restriction Maximum operating pressure, the main filler opening of load sensitive pump 1 is connected with the main filler opening of percussive hammer control valve 2, the main return opening of percussive hammer control valve 2 connects fuel tank 5, the pressure feedback Ls mouth of percussive hammer control valve 2 is connected with the control port X mouth of load sensitive pump 1, actuator port A with B of percussive hammer control valve 2 is connected with the main return opening of hydraulic impact hammer 3 and main filler opening respectively.The present invention program adopts the working pressure of hydraulic load responsive control technique simple realization needed for rock drill percussive hammer and flow matches demand, compared to the long-range Isobarically Control technology of traditional DRG, the program is because simplifying the quantity of system liquid casting die thus improve the reliability of rock drill percussive hammer hydraulic control system.In addition, reduce the restriction loss at valve port place the load-sensitive technology effective in scheme, thus achieve rock drill percussive hammer low energy consumption control.
Working pressure needed for rock drill percussive hammer and flow matches demand is realized for making the responsive control technique of hydraulic load, this programme have selected the percussive hammer control valve 2 shown in Fig. 2, percussive hammer control valve 2 is provided with two working positions, be respectively little impact position and large impact position, little impact position is communicated with the secondary relief of 90 bar on percussive hammer control valve 2 side, large impact position is communicated with the secondary relief of 130 bar on percussive hammer control valve 2 side, the size percussion action of switching shock hammer is carried out by switching shock position, wherein, the working position of percussive hammer control valve rated flow 1. and safety pressure are designed to 90l/min respectively, 90bar, working position rated flow 2. and safety pressure are designed to 120l/min, 130bar respectively.
As shown in Figure 1, the percussive hammer control valve of an A10VSODFR load sensitive pump and a band pressure sensor module can form a load sensing hydraulic control system.Wherein, load sensitive pump is integrated with the flow control valve 11 that regime flow exports and the pressure controlled valve 12 limiting pump Maximum operating pressure.When the system is operating, induced pressure is fed back to load sensitive pump control port by pressure sensor device by the percussive hammer control valve 2 of band pressure sensor module, and place also forms an equilibrium relation at flow control valve 11 two ends of pump, and being namely worth constant is 18bar.
Therefore, be not difficult to reach a conclusion according to throttle flow rate formula, the output flow of percussive hammer control valve
qonly depend on the opening area of valve, and have nothing to do with load variations thus ensure that the stability of system works.The energy loss of system mainly comes from the restriction loss in percussive hammer control valve place, and its energy loss is
, due to
value less (being about 18bar), the therefore restriction loss at series flow control valve place
also less, the low energy consumption achieving percussive hammer controls.
The present invention is when specifically using, first starting electrical machinery, pull percussive hammer control valve handle, it is made to be operated in little impact position 1., the rated flow 90l/min 1. required according to percussive hammer control bound position is carried out fuel feeding through oil circuit a to rock drill percussive hammer by oil hydraulic pump, and according to percussive hammer surge pressure and discharge relation, system just produces the surge pressure of 90bar, this surge pressure feeds back to the X mouth of pump through oil circuit c1, makes delivery side of pump delivery pressure P
bslightly larger than the pressure P of impacting oil circuit
l(P
b=P
l+ 18bar), Fig. 5 is the characteristic working curve of A10VSODFR variable displacement pump, system this will be operated in the A point position of Fig. 5 when little impact operating mode, from figure, characteristic curve is not difficult to find out.When there is change in surge pressure, the delivery pressure of pumping hole also followed by change, make the pressure reduction 18bar being added in multi-way valve remain constant, so just make 90l/min output flow be not hit hammer load variations impact thus improve the stability of system works.Again pull multi-way valve handle, make its be 1. switched to from little impact position large impact position 2. time, the rated flow 120l/min 2. required according to percussive hammer control bound position is carried out fuel feeding through oil circuit a to rock drill percussive hammer by oil hydraulic pump, according to the surge pressure in Fig. 1 and discharge relation figure, the hydraulic oil of 120l/min will produce the surge pressure of 130bar when flowing into impact hammer device, this surge pressure feeds back to the X mouth of pump through oil circuit c1, make delivery side of pump delivery pressure close to the pressure impacting oil circuit, and now system will be operated in the B point position of Fig. 5.In addition, because delivery side of pump delivery pressure is slightly larger than the pressure impacting oil circuit, the front and back pressure reduction therefore flowing through valve port place is less, according to restriction loss formula △ P=△
p*qknown, the restriction loss that valve port place causes is also less, so this system schema energy consumption is less.
From analyzing above, adopt load sensing hydraulic control system scheme simply to achieve the holding function of rock drill percussive hammer, the hydraulic control system of less hydraulic parts usage quantity composition substantially increases the reliability of system works.In addition, performance is improved in following two compared to traditional DRG long-range Isobarically Control technological scheme: one is that the restriction loss at throttle valve group place is less, and therefore energy consumption is less; Two be throttle valve group place export flow q not with the impact of load variations, therefore system works stability is better.
Claims (4)
1. the hydraulic control system of a rock drill percussive hammer, it is characterized in that comprising load sensitive pump (1), the percussive hammer control valve (2) of a band pressure sensor module, hydraulic impact hammer (3), motor (4) and hydraulic oil container (5), described load sensitive pump (1) is driven by motor (4), and on load sensitive pump (1), be integrated with the flow control valve (11) of regime flow output and the pressure controlled valve (12) of the system of restriction Maximum operating pressure, the main filler opening of described load sensitive pump (1) is connected with the main filler opening of percussive hammer control valve (2), the main return opening of percussive hammer control valve (2) connects fuel tank (5), the pressure feedback Ls mouth of percussive hammer control valve (2) is connected with the control port X mouth of load sensitive pump (1), actuator port A with B of percussive hammer control valve (2) is connected with the main return opening of hydraulic impact hammer (3) and main filler opening respectively.
2. the hydraulic control system of rock drill percussive hammer according to claim 2, it is characterized in that described percussive hammer control valve (2) is provided with two working positions, be respectively little impact position and large impact position, described little impact position is communicated with the secondary relief of 90 bar on percussive hammer control valve (2) side, and large impact position is communicated with the secondary relief of 130 bar on percussive hammer control valve (2) side.
3. the hydraulic control system of rock drill percussive hammer according to claim 3, it is characterized in that described pressure controlled valve (12) limits system Maximum operating pressure is 210-230 bar, and the hydraulic control mouth pressure reduction at flow control valve (11) two ends is 18 bar.
4. the hydraulic control system of rock drill percussive hammer according to claim 4, it is characterized in that described percussive hammer control valve (2) is provided with pressure sensor module, induced pressure in this pressure sensor module monitoring system, and be fed back to the control port X mouth of load sensitive pump (1) in real time, load sensitive pump (1) outlet pressure is, form equilibrium relation at flow control valve (11) two ends like this, namely value is for constant; Be not difficult to reach a conclusion according to throttle flow rate formula, the output flow of percussive hammer control valve (2)
qonly depend on the opening area of flow control valve (11), and have nothing to do with load variations thus ensure that the stability of system works; The energy loss of this system mainly comes from the restriction loss in percussive hammer control valve place, and its energy loss is, because value is less, therefore the restriction loss at series flow control valve place is also less, and the low energy consumption achieving percussive hammer controls.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201510473200.3A CN105114373B (en) | 2015-08-05 | 2015-08-05 | The hydraulic control system of rock drill jump bit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510473200.3A CN105114373B (en) | 2015-08-05 | 2015-08-05 | The hydraulic control system of rock drill jump bit |
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| CN105114373B CN105114373B (en) | 2018-09-25 |
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| CN201510473200.3A Active CN105114373B (en) | 2015-08-05 | 2015-08-05 | The hydraulic control system of rock drill jump bit |
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Cited By (2)
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| CN107543734A (en) * | 2017-08-17 | 2018-01-05 | 张日龙 | A kind of test system and its method of testing of hydraulic gate performance |
| CN107893626A (en) * | 2017-12-20 | 2018-04-10 | 山东天瑞重工有限公司 | A kind of closed hydraulic drill work system |
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| CN105114373B (en) | 2018-09-25 |
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