CN105332967B - Self-adaptive valve bank for rock drilling machine - Google Patents
Self-adaptive valve bank for rock drilling machine Download PDFInfo
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- CN105332967B CN105332967B CN201510912690.2A CN201510912690A CN105332967B CN 105332967 B CN105332967 B CN 105332967B CN 201510912690 A CN201510912690 A CN 201510912690A CN 105332967 B CN105332967 B CN 105332967B
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Abstract
The invention discloses a self-adaptive valve bank for a rock drilling machine. The self-adaptive valve bank comprises a first sequence valve, a first hydraulic operated directional valve, a shuttle valve and the like. The self-adaptive valve bank for a rock drilling machine is simple in structure and high in reliability, the rock drilling machine and a rock drilling tool are protected, and meanwhile the hole-forming efficiency is improved.
Description
Technical field
The present invention relates to engineering machinery field, the self adaptation valve group of specially a kind of rock drilling machine.
Background technology
Hydraulic open-air rock drilling machine is the borehole engineering equipment used for pledge excavation, exploitation of stone etc..Due to rock
The wide variety of stone, strata condition is complicated, causes the rotational resistance in drilling suffered by drill bit suddenly to increase card.Such as
Fruit rock drilling system can not in time process the drill bit of burst by card situation, rotation motor will be caused to exceed and can bear scope, cause
The drilling tool cards such as the related drilling rod of drill bit, adapter sleeve so that user bears larger economic loss, and have a strong impact on pore-forming efficiency.
Initial down-hole percussion drill all uses Pneumatic rotary motor, and moment of torsion is small, it is impossible to which effective broken rock, drilling speed is low, completely not
Possess anti-sticking function, be eliminated now.The down-the-hole drill and top hammer formula rock drilling machine developed on later domestic market are all
The hydraulic motor of high pulling torque is used instead to implement spinfunction.Wherein, some anti-sticking systems are by complicated guide's reponse system reality
Existing, or design is complicated, reaction speed is slower, and anti-sticking effect is bad, otherwise then because response upward strain speed is too fast, return compared with
Slowly, pore-forming effect is had a strong impact on.Some use micro computer control, although reaction speed is fast, but reliability is poor, harsh
Under site environment, circuit and part easily go wrong, if being unable to on-call maintenance replacing, can cause heavy losses to user.
The content of the invention
It is an object of the invention to provide a kind of self adaptation valve group of rock drilling machine, its simple structure, reliability are high, can
Effectively improve pore-forming efficiency.
The self adaptation valve group of rock drilling machine of the present invention, including：The rotation of the first sequence valve, its oil inlet and this valve group
Turn the connection of pressure signal hydraulic fluid port, when the rotation feed signal hydraulic fluid port pressure more than the first sequence valve setting pressure when, the
The commutation of one sequence valve turns on its oil inlet and oil-out；The feed pressure of the first pilot operated directional control valve, its oil inlet and this valve group
Hydraulic fluid port is connected, and its oil return opening connects with the oil return opening of valve group, two actuator ports of first pilot operated directional control valve respectively with valve group
Propulsion hydraulic fluid port with above carry hydraulic fluid port and connect；Second pilot operated directional control valve, its oil inlet is connected with propulsion guide's hydraulic fluid port of valve group, and its is fuel-displaced
Mouthful mouthful connected with a hydraulic control of the first pilot operated directional control valve, the hydraulic control mouth of second pilot operated directional control valve and going out for first sequence valve
Hydraulic fluid port is connected；Shuttle valve, its first oil inlet is connected with the oil-out of the first sequence valve, and its second oil inlet is above carried with the valve group
Guide's hydraulic fluid port is connected, and the oil-out of the shuttle valve is connected with another hydraulic control mouthful of the first pilot operated directional control valve；Also include the second order
Valve, its oil inlet is connected with rotation feed signal hydraulic fluid port, and its oil-out is connected with the first oil inlet of shuttle valve, second order
The setting pressure of the setting pressure more than the first sequence valve of valve, when the pressure of the rotation feed signal hydraulic fluid port is more than the second order
During the setting pressure of valve, the commutation of the second sequence valve turns on its oil inlet and oil-out.
Preferably, also including manual switch valve, the pressure oil of the rotation feed signal hydraulic fluid port is after the manual switch valve
Flow into valve group part.
Preferably, also including the first overflow valve, the oil inlet of first overflow valve is connected with the feed pressure hydraulic fluid port of valve group,
Its oil-out is connected with the oil return opening of valve group.
Preferably, also including the 3rd pilot operated directional control valve and the second overflow valve, the oil inlet of the 3rd pilot operated directional control valve with
The surge hydraulic fluid port connection of valve group, its oil-out is connected with the oil inlet of the second overflow valve, the liquid of the 3rd pilot operated directional control valve
Control mouth is connected with the propulsion hydraulic fluid port of valve group, and the oil-out of second overflow valve is connected with the oil return opening of valve group.
Preferably, also including the 3rd sequence valve, its oil inlet is connected with the propulsion hydraulic fluid port of valve group, its oil-out and described
The hydraulic control of three pilot operated directional control valves mouthful connection, when the propulsion hydraulic fluid port pressure more than the 3rd sequence valve setting pressure when, the 3rd
Sequence valve commutation turns on its oil inlet and oil-out.
Preferably, it is provided with damping on the oil circuit between the oil-out of first sequence valve and the first oil inlet of shuttle valve
Hole.
Preferably, it is provided with damping hole after the oil return opening of second sequence valve.
Preferably, also including the 3rd overflow valve, the oil inlet of the 3rd overflow valve is connected with the surge hydraulic fluid port of valve group,
Its oil-out is connected with the oil return opening of valve group.
Preferably, also including the 4th overflow valve, the oil inlet of the 4th overflow valve is connected with the propulsion hydraulic fluid port of valve group, and it goes out
Hydraulic fluid port is connected with the oil return opening of valve group.
The present invention reduces surge while realizing that anti-sticking pricker is automatically controlled, and protects rock drill and drilling tool, has
Effect reduces the use cost of user.And set by two-stage sequence valve and corresponding damping hole, improve and put forward response control
Characteristic, reduces the time for carrying and being reset to and rework, and improves drilling efficiency.
Brief description of the drawings
Fig. 1 is hydraulic schematic diagram of the invention.
Specific embodiment
The present invention is further elaborated with reference to the accompanying drawings and examples, and following examples are only used for explaining this
Invention, is not intended to limit the scope of the present invention..
The self adaptation valve group of rock drilling machine as shown in Figure 1, wherein, oil inlet and the rotation of the manual switch valve 1 are pressed
Force signal hydraulic fluid port K is connected, and pressure oil is entered by the rotation feed signal hydraulic fluid port K of valve group, is flowed into again by after the manual switch valve 1
First sequence valve 2 and the second sequence valve 3 of valve group.Anti-sticking function of the invention can be closed by the manual switch valve 1.Close
Afterwards, the maximum constraint of rotational pressure is the maximum pressure of default.
The oil inlet of first sequence valve 2 is connected with the oil-out of manual switch valve 1, the draining of its oil return opening and valve group
Mouth L connections, the oil-out of first sequence valve 2 is connected with the hydraulic control mouthful of the second pilot operated directional control valve 11 all the way, another road first
Connected with the first oil inlet of shuttle valve 4 after the damping hole 6 of filter 5 and first.When the pressure of the rotation feed signal hydraulic fluid port K surpasses
When crossing the setting pressure of the first sequence valve 2, pilot pressure oil acts on its hydraulic control end, drives the commutation of the first sequence valve to make its oil-feed
Mouth and oil-out conducting.
The oil inlet of second sequence valve 3 is connected with the oil-out of manual switch valve 1, and its oil-out is through the second filter
Connected with the first oil inlet of shuttle valve 4 after 7, the oil return opening of second sequence valve is successively through the second damping hole 8 and the 3rd damping hole 9
Connected with the drain tap L of valve group afterwards.The setting pressure of second sequence valve 3 is more than the first sequence valve 2, when the rotational pressure
The pressure of signal hydraulic fluid port more than the second sequence valve setting pressure when, pilot pressure oil acts on its hydraulic control end, drives second suitable
The commutation of sequence valve turns on its oil inlet and oil-out.
Second oil inlet of the shuttle valve 4 is connected with guide's hydraulic fluid port X2 that above carries of valve group, and its oil-out is changed with the first hydraulic control
To the upper extract control mouthful connection of valve 10.
The oil inlet of second pilot operated directional control valve 11 is connected with propulsion guide's hydraulic fluid port X1 of valve group, its oil return opening and valve group
Drain tap L connections, the propulsion hydraulic control mouth of its oil-out and the first pilot operated directional control valve 10 connects.
The oil inlet of first pilot operated directional control valve 10 is connected with the feed pressure hydraulic fluid port P of this valve group, its oil return opening and valve
The oil return inlet T connection of group, two actuator ports of first pilot operated directional control valve respectively with the propulsion hydraulic fluid port A1 of valve group and above carry hydraulic fluid port
B1 correspondences are connected.Pressure oil by the valve group propulsion hydraulic fluid port A1 or above carry hydraulic fluid port B1 draw, for the feed motion of rock drill
（Advance downwardly and upper actuating is made upwards）.
The oil inlet of first overflow valve 12 is connected with the feed pressure hydraulic fluid port P of valve group, and its oil-out is returned with valve group
Hydraulic fluid port T is connected.
The oil inlet of the 4th overflow valve 14 is connected with the propulsion hydraulic fluid port A1 of valve group, the oil return opening of its oil-out and valve group
T is connected.
The oil inlet of the 3rd sequence valve 13 is connected with the propulsion hydraulic fluid port A1 of valve group, its oil-out and the 3rd hydraulic control
The hydraulic control mouthful connection of reversal valve 15, its oil return opening is connected with the drain tap L of valve group.When the pressure of the propulsion hydraulic fluid port A1 is more than the
During the setting pressure of three sequence valves, pilot pressure oil acts on its hydraulic control end, drive the commutation of the 3rd sequence valve make its oil inlet and
Oil-out is turned on.
The oil inlet of the 3rd pilot operated directional control valve 15 is connected with the surge hydraulic fluid port C of valve group, its oil-out and second
The oil inlet connection of overflow valve 16, the oil-out of second overflow valve 16 is connected with the oil return inlet T of valve group.
The oil inlet of the 3rd overflow valve 17 is connected with the surge hydraulic fluid port C of valve group, and its oil-out is returned with valve group
Hydraulic fluid port T is connected.
The operation principle of above-mentioned valve group is：
In normal rock drilling, pressure oil is entered by feed pressure hydraulic fluid port P.Now, propulsion pilot signal oil is by advancing guide
Hydraulic fluid port X1 enters, and promotes the first pilot operated directional control valve 10 to commutate by the second pilot operated directional control valve 11, and pressure oil is drawn by propulsion hydraulic fluid port A1
Go out to enter propulsion motor, hydraulic fluid port B1 oil returns are proposed from above.Meanwhile, the 3rd sequence valve 13 controlled by propelling pressure replaces, pressure oil
Act in the hydraulic control mouthful of the 3rd pilot operated directional control valve 15, the commutation of the 3rd pilot operated directional control valve blocks its oil inlet and outlet, now impacts
Pressure is set up by the 3rd overflow valve 17, so as to realize the elevated pressures of surge hydraulic fluid port C.
When drilling tool runs into a certain degree of jam, the positive rotation pressure of rotation feed signal hydraulic fluid port K is suitable more than first
Sequence valve 2 and less than the second sequence valve 3 setting pressure, first sequence valve oil inlet and outlet conducting, pressure oil reach second
The hydraulic control end of pilot operated directional control valve 11, promotes the commutation of the second pilot operated directional control valve, ends its oil inlet, the first pilot operated directional control valve 10
Propulsion hydraulic control end the second pilot operated directional control valve port valve group drain tap L.At this moment the first pilot operated directional control valve 10 returns to middle position, feeds rock drilling
Action stops, and because now spinning movement is being carried out always, but is pressed in the power vanishing on rock so that rotational resistance diminishes.
And because feeding stopping causes propelling pressure to be reduced to zero, therefore the return of the 3rd sequence valve 13 controlled by propelling pressure, make the
The drain tap L of the hydraulic control end port valve group of three pilot operated directional control valves 15, the 3rd pilot operated directional control valve 15 is turned on, and is come from surge hydraulic fluid port C
The surge oil connection pressure release of the second overflow valve 16, so as to realize relatively low surge, protect rock drill and drilling tool.If
When rotational pressure now drops below the setting value of the first sequence valve 2, the first sequence valve return then restarts to push to push away
Enter rock drilling.In addition, making the first order valve events in rotational pressure described above, while pressing action stops, first is suitable
Another road pressure oil that sequence valve 2 is drawn guides to the first pilot operated directional control valve 10 through the first filter 5, the first damping hole 6 and shuttle valve 4
Upper extract control end, and through the first damping hole hydraulic oil while the upper extract control end of the first pilot operated directional control valve is guided to, also
Drain tap L is guided to by the damping hole of oil return opening, second and the 3rd of the second sequence valve 3, so that causing extract control end
Rate of pressure rise slows down.It can be seen that, corresponding speed is carried in the presence of damping hole, on rock drill slower.During upper carrying, rotation
Turning pressure is further reduced, and when the setting value less than the first sequence valve 2, then restarts to push rock drilling, recovers normal
Rock drilling state.Therefore above carried due to rock drill less or do not carried above, the danger of card pricker is eliminated the need for, and recover quickly to normal rock drilling
State, improves rock penetration performance.
When drilling tool runs into the situation of special card, rotational pressure is raised suddenly, higher than the first sequence valve 2 and the second sequence valve
3 setting value, now the action simultaneously of the first and second sequence valves, on the one hand lets out the propulsion hydraulic control end of the first pilot operated directional control valve 10
Pressure, the on the other hand oil inlet and outlet conducting of second sequence valve 3, hydraulic oil acts on the through the second sequence valve and shuttle valve are rapid
On the upper extract control end of one pilot operated directional control valve 10 so that the first pilot operated directional control valve commutates, when pilot control is still to push rock drilling,
It is fast automatic above to carry, so that rotational pressure declines rapidly.Similarly, punching is made because the pressure for advancing oil circuit is zero in upper carrying
The second overflow valve of oil communication 16 is hit, rock drill is worked with relatively low surge, is played a protective role.
Claims (9)
1. the self adaptation valve group of a kind of rock drilling machine, it is characterised in that including：
First sequence valve, its oil inlet is connected with the rotation feed signal hydraulic fluid port of this valve group, when the rotation feed signal hydraulic fluid port
Pressure more than the first sequence valve setting pressure when, the commutation of the first sequence valve turns on its oil inlet and oil-out；
First pilot operated directional control valve, its oil inlet is connected with the feed pressure hydraulic fluid port of this valve group, the oil return opening of its oil return opening and valve group
Connection, two actuator ports of first pilot operated directional control valve respectively with the propulsion hydraulic fluid port of valve group and above carry hydraulic fluid port and connect；
Second pilot operated directional control valve, its oil inlet is connected with propulsion guide's hydraulic fluid port of valve group, its oil-out and the first pilot operated directional control valve
A hydraulic control mouthful connection, the hydraulic control mouthful of second pilot operated directional control valve connects with the oil-out of first sequence valve；
Shuttle valve, its first oil inlet is connected with the oil-out of the first sequence valve, and its second oil inlet above carries guide with the valve group
Hydraulic fluid port is connected, and the oil-out of the shuttle valve is connected with another hydraulic control mouthful of the first pilot operated directional control valve；Including the second sequence valve, it enters
Hydraulic fluid port is connected with rotation feed signal hydraulic fluid port, its oil-out is connected with the first oil inlet of shuttle valve, and second sequence valve sets
Constant-pressure is more than the setting pressure of the first sequence valve, when pressure the setting more than the second sequence valve of the rotation feed signal hydraulic fluid port
During constant-pressure, the commutation of the second sequence valve turns on its oil inlet and oil-out.
2. the self adaptation valve group of rock drilling machine according to claim 1, it is characterised in that：It is described including manual switch valve
The pressure oil of rotation feed signal hydraulic fluid port flows into valve group part after the manual switch valve.
3. the self adaptation valve group of rock drilling machine according to claim 1, it is characterised in that：Including the first overflow valve, this
The oil inlet of one overflow valve is connected with the feed pressure hydraulic fluid port of valve group, and its oil-out is connected with the oil return opening of valve group.
4. the self adaptation valve group of rock drilling machine according to claim 1, it is characterised in that：Including the 3rd pilot operated directional control valve and
Second overflow valve,
The oil inlet of the 3rd pilot operated directional control valve is connected with the surge hydraulic fluid port of valve group, its oil-out and the second overflow valve
Oil inlet is connected, and the hydraulic control of the 3rd pilot operated directional control valve mouthful is connected with the propulsion hydraulic fluid port of valve group, second overflow valve it is fuel-displaced
Mouth is connected with the oil return opening of valve group.
5. the self adaptation valve group of rock drilling machine according to claim 4, it is characterised in that：Including the 3rd sequence valve, it enters
Hydraulic fluid port is connected with the propulsion hydraulic fluid port of valve group, and its oil-out is connected with the hydraulic control mouthful of the 3rd pilot operated directional control valve, when the propulsion
The pressure of hydraulic fluid port more than the 3rd sequence valve setting pressure when, the commutation of the 3rd sequence valve turns on its oil inlet and oil-out.
6. the self adaptation valve group of rock drilling machine according to claim 1, it is characterised in that：In going out for first sequence valve
Oil circuit between the first oil inlet of hydraulic fluid port and shuttle valve is provided with damping hole.
7. the self adaptation valve group of rock drilling machine according to claim 1, it is characterised in that：In returning for second sequence valve
Damping hole is provided with after hydraulic fluid port.
8. the self adaptation valve group of rock drilling machine according to claim 1, it is characterised in that：Including the 3rd overflow valve, this
The oil inlet of three overflow valves is connected with the surge hydraulic fluid port of valve group, and its oil-out is connected with the oil return opening of valve group.
9. the self adaptation valve group of rock drilling machine according to claim 1, it is characterised in that：Including the 4th overflow valve, this
The oil inlet of four overflow valves is connected with the propulsion hydraulic fluid port of valve group, and its oil-out is connected with the oil return opening of valve group.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510912690.2A CN105332967B (en) | 2015-12-11 | 2015-12-11 | Self-adaptive valve bank for rock drilling machine |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510912690.2A CN105332967B (en) | 2015-12-11 | 2015-12-11 | Self-adaptive valve bank for rock drilling machine |
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| Publication Number | Publication Date |
|---|---|
| CN105332967A CN105332967A (en) | 2016-02-17 |
| CN105332967B true CN105332967B (en) | 2017-05-24 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201510912690.2A Active CN105332967B (en) | 2015-12-11 | 2015-12-11 | Self-adaptive valve bank for rock drilling machine |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105351273B (en) * | 2015-12-11 | 2017-05-24 | 重庆纳川山隅重工设备有限公司 | Anti-jamming control valve group for fully-hydraulic opencast rock drill |
| CN107939757B (en) * | 2017-12-29 | 2024-03-12 | 徐州徐工能源装备有限公司 | Rock drilling control system of drill jumbo |
Family Cites Families (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI981707A0 (en) * | 1998-08-06 | 1998-08-06 | Tamrock Oy | An arrangement for controlling rock drilling |
| FI115552B (en) * | 2002-11-05 | 2005-05-31 | Sandvik Tamrock Oy | Arrangement for controlling rock drilling |
| FI123639B (en) * | 2005-04-15 | 2013-08-30 | Sandvik Mining & Constr Oy | Method and arrangement for controlling rock drilling |
| CN102747949B (en) * | 2012-07-19 | 2014-06-11 | 山河智能装备股份有限公司 | Fast propulsion hydraulic control loop of down-the-hole drill rig |
| CN203022763U (en) * | 2012-11-30 | 2013-06-26 | 中煤科工集团重庆研究院 | Hydraulic control system of drill loader |
| CN203627375U (en) * | 2013-12-20 | 2014-06-04 | 中铁工程装备集团有限公司 | Novel drill jumbo integrated control valve block |
| CN203769756U (en) * | 2014-01-09 | 2014-08-13 | 中南大学 | Quick-response anti-blockage hydraulic rock drilling control system |
| CN203716837U (en) * | 2014-02-28 | 2014-07-16 | 金川集团股份有限公司 | Anti-clamping bit hydraulic control system for rock drill |
| CN103821777B (en) * | 2014-02-28 | 2016-04-13 | 金川集团股份有限公司 | The continuously adjustable hydraulic control system of rock drill power |
| CN204200733U (en) * | 2014-10-11 | 2015-03-11 | 山河智能装备股份有限公司 | A kind of rock drilling machine propelling pressure hydraulic pressure far controls loop |
| CN204512026U (en) * | 2015-02-11 | 2015-07-29 | 阿特拉斯科普柯(南京)建筑矿山设备有限公司 | The anti-solution cavity card pricker system of drill jumbo |
| CN205388056U (en) * | 2015-12-11 | 2016-07-20 | 重庆纳川山隅重工设备有限公司 | Rock drilling machine's self -adaptation valves |
| CN105351273B (en) * | 2015-12-11 | 2017-05-24 | 重庆纳川山隅重工设备有限公司 | Anti-jamming control valve group for fully-hydraulic opencast rock drill |
| CN205423369U (en) * | 2015-12-11 | 2016-08-03 | 重庆纳川山隅重工设备有限公司 | All -hydraulic open -air rock drilling machine's anti -sticking borer valve unit |
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