CN203081878U - Hydraulic control system and engineering machine - Google Patents

Hydraulic control system and engineering machine Download PDF

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Publication number
CN203081878U
CN203081878U CN 201320060600 CN201320060600U CN203081878U CN 203081878 U CN203081878 U CN 203081878U CN 201320060600 CN201320060600 CN 201320060600 CN 201320060600 U CN201320060600 U CN 201320060600U CN 203081878 U CN203081878 U CN 203081878U
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China
Prior art keywords
oil
valve
circuit
control system
pressure
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CN 201320060600
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徐茂林
叶民杰
禹小良
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Zoomlion Heavy Industry Science and Technology Co Ltd
Zoomlion Heavy Industry Science and Technology Co Ltd Weinan Branch
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Zoomlion Heavy Industry Science and Technology Co Ltd
Zoomlion Heavy Industry Science and Technology Co Ltd Weinan Branch
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Priority to CN 201320060600 priority Critical patent/CN203081878U/en
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Abstract

The utility model provides a hydraulic control system and an engineering machine. The hydraulic control system comprises an oil cylinder, a reversing valve, a pressure oil circuit, an oil discharging oil circuit, a first working oil circuit and a second working oil circuit. The reversing valve comprises a pressure oil opening, an oil discharging opening, a first working oil opening and a second working oil opening. The pressure oil opening is connected with the pressure oil circuit, the oil discharging opening is connected with the oil discharging oil circuit, the first working oil opening is connected with a rod end chamber of the oil cylinder through the first working oil circuit, and the second working oil opening is connected with a non-rod end chamber of the oil cylinder through the second working oil circuit. The oil discharging oil circuit comprises a first backpressure device which is connected on the oil discharging oil circuit in series, and an entrance end of the backpressure device is connected with the oil discharging opening. The hydraulic control system further comprises a bypass oil circuit, a first end of the bypass oil circuit is connected with the second working oil circuit, and a second end of the bypass oil circuit is connected with an exit end of the first backpressure device. The bypass oil circuit comprises a bypass control valve set used for controlling on-off of the bypass oil circuit. According to the hydraulic control system and the engineering machine, the aim of reducing backpressure of return oil of the oil cylinder by utilizing the bypass oil circuit can be achieved.

Description

Hydraulic control system and engineering machinery
Technical field
The utility model relates to engineering machinery field, more specifically, relates to a kind of hydraulic control system and engineering machinery.
Background technique
Fig. 1 shows hydraulic control system of excavator in the prior art.
This hydraulic control system comprises hydraulic oil container 10, variable displacement pump 20, safety valve 30, selector valve 40, oil cylinder 70, pressure oil circuit 81, oil extraction oil circuit 82, first working oil path 83 and second working oil path 84.Pressure oil circuit 81 comprises serial connection one-way valve 60 thereon.Oil extraction oil circuit 82 comprises serial connection back pressure valve 50 thereon.The entry end of safety valve 30 connects pressure oil circuit 81, and outlet end connects oil extraction oil circuit 82, to play voltage-limiting protection when the outlet pressure oil superpressure of variable displacement pump 20.
Wherein, selector valve 40 comprises pressure hydraulic fluid port P, oil drain out T, the first actuator port A and the second actuator port B.Pressure hydraulic fluid port P is connected with pressure oil circuit 81, oil drain out T is connected with oil extraction oil circuit 82, the first actuator port A is connected with the rod chamber 72 of oil cylinder 70 by first working oil path 83, the second actuator port B is connected with the rodless cavity 71 of oil cylinder 70 by second working oil path 84, the entry end of back pressure valve 50 is connected with oil drain out T, and the outlet end of back pressure valve 50 is connected with fuel tank 10.The spool 41 of selector valve 40 changes valve position under the control of the rod chamber oil-feed control oil channel 86 of hydraulic control system and rodless cavity oil-feed control oil channel 87, thereby changes the rod chamber 72 of oil cylinder 70 and the oil-feed or the oil return state of rodless cavity 71.
In the above prior art, the oil-feed of whole hydraulic control system be by variable displacement pump 20 through selector valve 40 to oil cylinder 70, oil return be by oil cylinder 70 through selector valve 40 through back pressure valve 50 to fuel tank 10.Oil cylinder 70 is an actuator, controls the to-and-fro motion of oil cylinder 70 by the displacement of spool 41 of control selector valve 40.The oil return of oil cylinder 70 flow through selector valve 40 and back pressure valve 50 then flow back to fuel tank 10.The parameter that can determine return oil pressure in the oil return process of oil cylinder 70 has only selector valve 40 and back pressure valve 50 except the travelling speed of oil cylinder 70.And back pressure valve 50 is owing to be that a plurality of control valves are shared, and general setting value is also lower, and its value can't arbitrarily be changed, and has only control selector valve 40 so will adjust the return oil pressure of oil cylinder 70.
The oil return of oil cylinder 70 is flowed back to fuel tank 10 by selector valve 40 in the above hydraulic control system, can only adjust the return oil pressure of oil cylinder 70 by regulating selector valve 40 spools 41.Return oil pressure is that spool 41 flow areas by selector valve 40 decide.And spool 41 flow areas of selector valve 40 are by the structures shape of spool 41.Steady for the motion that makes oil cylinder 70, spool 41 flow areas of selector valve 40 are limited within certain scope, so the adjustment of the spool 41 of selector valve 40 is limited.When bigger recirculating oil quantity, as rod chamber 72 oil-feeds of oil cylinder 70 and during rodless cavity 71 oil returns, under the situation that does not reduce oil cylinder 70 movement velocitys, more than the oil return flow increases 2 times usually, under the situation of spool 41 flow areas that can't increase selector valve 40 again, the return oil pressure of oil cylinder 70 can increase, and return oil pressure increases can cause the increase of hydraulic control system pressure.Therefore, because the versatility and the accuracy of selector valve 40 cause above hydraulic control system can't guarantee that the return oil pressure of all oil cylinders 70 is within ideal range.And the absorbed power of variable displacement pump is the product of flow and pressure, and pressure increases, and the pump absorbed power increases, and causes engine output to increase, thereby increases the power loss of motor, and then influences the working efficiency of excavator or cause unnecessary fuel oil loss.Can cause POF to reduce on the constant output pump if be used in, reduce oil cylinder 70 operating rates, also can influence working efficiency.
The model utility content
The utility model purpose is to provide a kind of hydraulic control system and engineering machinery, can avoid the engine power loss or the fuel oil loss that cause because of return oil pressure is too high.
The utility model provides a kind of hydraulic control system, comprise oil cylinder, selector valve, the pressure oil circuit, the oil extraction oil circuit, first working oil path and second working oil path, selector valve comprises the pressure hydraulic fluid port, oil drain out, first actuator port and second actuator port, the pressure hydraulic fluid port is connected with the pressure oil circuit, oil drain out is connected with the oil extraction oil circuit, first actuator port is connected with the rod chamber of oil cylinder by first working oil path, second actuator port is connected with the rodless cavity of oil cylinder by second working oil path, the oil extraction oil circuit comprises serial connection first back pressure apparatus thereon, and the entry end of first back pressure apparatus is connected with oil drain out, hydraulic control system also comprises bleed off circuit, first end of bleed off circuit is connected with second working oil path, second end of bleed off circuit is connected with the outlet end of first back pressure apparatus, and bleed off circuit comprises the bypass control valve (BCV) group of control bleed off circuit break-make.
Further, the bypass control valve (BCV) group comprises cartridge valve that is serially connected with on the bleed off circuit and the cartridge valve control valve group of controlling the cartridge valve break-make, the entry end of cartridge valve is connected with second working oil path, the outlet end of cartridge valve is connected with the outlet end of first back pressure apparatus, and the control end of cartridge valve is connected with cartridge valve control valve group.
Further, hydraulic control system also comprises rod chamber oil-feed control oil channel, and rod chamber oil-feed control oil channel is used to control selector valve and changes valve position, so that the rod chamber oil-feed of oil cylinder; Cartridge valve control valve group comprises the Pilot operated check valve and second back pressure apparatus, the entry end of Pilot operated check valve is connected with the entry end of second back pressure apparatus, the outlet end of Pilot operated check valve is connected with the control mouth of cartridge valve, the control mouth of Pilot operated check valve is connected with rod chamber oil-feed control oil channel, and the outlet end of second back pressure apparatus is connected with the outlet end of cartridge valve.
Further, second back pressure apparatus is relief valve or back pressure valve.
The utility model also provides a kind of engineering machinery, comprises hydraulic control system, and wherein hydraulic control system is aforesaid hydraulic control system.
Further, engineering machinery is an excavator.
According to hydraulic control system of the present utility model and engineering machinery, can realize utilizing bleed off circuit to reduce the purpose of the return oil pressure of oil cylinder.When oil cylinder oil return flow excessive, and the spool flow area of selector valve can not increase when causing return oil pressure greater than ideal value again, can control bleed off circuit opens, the part oil return is discharged through bleed off circuit, thereby can make return oil pressure near ideal value, avoid the engine power loss or the fuel oil loss that cause because of return oil pressure is too high.
Description of drawings
The accompanying drawing that constitutes the application's a part is used to provide further understanding of the present utility model, and illustrative examples of the present utility model and explanation thereof are used to explain the utility model, do not constitute improper qualification of the present utility model.In the accompanying drawings:
Fig. 1 is the principle schematic of the hydraulic control system of prior art;
Fig. 2 is the principle schematic according to the utility model embodiment's hydraulic control system.
Embodiment
Describe the utility model below with reference to the accompanying drawings and in conjunction with the embodiments in detail.Need to prove that under the situation of not conflicting, embodiment and the feature among the embodiment among the application can make up mutually.
Hydraulic control system of the present utility model comprises oil cylinder, selector valve, pressure oil circuit, oil extraction oil circuit, first working oil path and second working oil path.Selector valve comprises pressure hydraulic fluid port, oil drain out, first actuator port and second actuator port.The pressure hydraulic fluid port of selector valve is connected with the pressure oil circuit; Oil drain out is connected with the oil extraction oil circuit; First actuator port is connected with the rod chamber of oil cylinder by first working oil path; Second actuator port is connected with the rodless cavity of oil cylinder by second working oil path.The oil extraction oil circuit comprises serial connection first back pressure apparatus thereon, and the entry end of first back pressure apparatus is communicated with oil drain out.Wherein, hydraulic control system also comprises bleed off circuit, and first end of bleed off circuit is connected with second working oil path, and second end of bleed off circuit is connected with the outlet end of first back pressure apparatus, and bleed off circuit comprises the bypass control valve (BCV) group of control bleed off circuit break-make.
Hydraulic control system of the present utility model can realize utilizing bleed off circuit to reduce the purpose of the return oil pressure of oil cylinder.Oil cylinder oil return flow is excessive under some state, and the spool flow area of selector valve can not increase when causing return oil pressure greater than ideal value again, can control bleed off circuit opens, the part oil return is discharged through bleed off circuit, thereby can make return oil pressure near ideal value, avoid the engine power loss or the fuel oil loss that cause because of return oil pressure is too high.
Hydraulic control system of the present utility model is applicable to all kinds of engineering machinery that need oil cylinder as actuator, and for example excavator especially is applicable to the large hydraulic excavator.
Below in conjunction with Fig. 2 the utility model embodiment is described in detail.
As shown in Figure 2, the hydraulic control system of present embodiment comprises hydraulic oil container 10, variable displacement pump 20, safety valve 30, selector valve 40, oil cylinder 70, pressure oil circuit 81, oil extraction oil circuit 82, first working oil path 83, second working oil path 84 and bleed off circuit 85.
Wherein, selector valve 40 comprises pressure hydraulic fluid port P, oil drain out T, the first actuator port A and the second actuator port B.Pressure hydraulic fluid port P is communicated with hydraulic oil container 10 by variable displacement pump 20, connecting pipeline between pressure hydraulic fluid port P and the variable displacement pump 20 is a pressure oil circuit 81, oil drain out T is communicated with hydraulic oil container 10 by back pressure valve 50, connecting pipeline between oil drain out T and the hydraulic oil container 10 is an oil extraction oil circuit 82, the first actuator port A is connected with the rod chamber 72 of oil cylinder 70 by first working oil path 83, the second actuator port B is connected with the rodless cavity 71 of oil cylinder 70 by second working oil path 84, the entry end of back pressure valve 50 is connected with oil drain out T, and the outlet end of back pressure valve 50 is connected with fuel tank 10.Pressure oil circuit 81 comprises serial connection one-way valve 60 thereon.Oil extraction oil circuit 82 comprises the back pressure valve 50 of serial connection conduct first back pressure apparatus thereon.Bleed off circuit 85 comprises the bypass control valve (BCV) group 100 of controlling these bleed off circuit 85 break-makes.The entry end of safety valve 30 connects pressure oil circuit 81, and outlet end connects oil extraction oil circuit 82, plays voltage-limiting protection when the outlet pressure oil superpressure of variable displacement pump 20.
In the present embodiment, selector valve 40 is specially three six-way transfer valves.Selector valve 40 also comprises first control end and second control end, and first control end is connected with the rod chamber oil-feed control oil channel 86 of oil cylinder 70, and second control end is connected with the rodless cavity oil-feed control oil channel 87 of oil cylinder 70.The spool 41 of selector valve 40 changes the position under the control of the rod chamber oil-feed control oil channel 86 of hydraulic control system and rodless cavity oil-feed control oil channel 87, thereby changes the rod chamber 72 of oil cylinder 70 and the oil-feed or the oil return state of rodless cavity 71.Wherein rod chamber oil-feed control oil channel 86 is in rod chamber 72 oil-feeds of oil cylinder 70 when pressure condition is arranged.Rodless cavity oil-feed control oil channel 87 is in rodless cavity 71 oil-feeds of oil cylinder 70 when pressure condition is arranged.
Selector valve 40 also comprises respectively and is connected the 3rd actuator port and the 4th actuator port with oil extraction oil circuit 82 with pressure oil circuit 81.Selector valve 40 is when meta, and the 3rd actuator port of this selector valve 40 and the 4th actuator port are communicated with, and is used for the pressure oil of variable displacement pump 20 outlets is directly entered fuel tank 10, and the 3rd actuator port of this selector valve 40 and the 4th actuator port disconnect when all the other working positions.
The pressure hydraulic fluid port P of selector valve 40 is connected with pressure oil circuit 81.Variable displacement pump 20 is sent the hydraulic-pressure pump in the fuel tank 10 into pressure oil circuit 81.Oil drain out T is connected with oil extraction oil circuit 82.Oil extraction oil circuit 82 is connected with fuel tank 10, is used for the oil return of oil cylinder 70 is entered fuel tank 10.The first actuator port A of selector valve 40 is connected with the rod chamber 72 of oil cylinder 70 by first working oil path 83.The second actuator port B of selector valve 40 is connected with the rodless cavity 71 of oil cylinder 70 by second working oil path 84.Back pressure valve 50 is serially connected with on the oil extraction oil circuit 82 and the entry end of back pressure valve 50 is connected with oil drain out T, and the outlet end of back pressure valve 50 is connected with fuel tank 10, thereby oil cylinder 70 need flow back to fuel tank 10 through back pressure valve 50 through the oil return of oil extraction oil circuit 82.First end of bleed off circuit 85 is connected with second working oil path 84, and second end of bleed off circuit 85 is connected with the outlet end of back pressure valve 50, and the 3rd end of bleed off circuit 85 is connected with first control end of selector valve 40.
As shown in Figure 2, bypass control valve (BCV) group 100 comprises cartridge valve 130 that is serially connected with on the bleed off circuit 85 and the cartridge valve control valve group of controlling cartridge valve 130 break-makes particularly.The entry end P1 of cartridge valve 130 is connected with second working oil path 84, and the outlet end T1 of cartridge valve 130 is connected with the outlet end of back pressure valve 50.Cartridge valve control valve group is connected with the control mouth K1 of cartridge valve 130, to control the break-make of cartridge valve 130 by the oil pressure that changes control mouthful K1.
In the present embodiment, the cartridge valve control valve group of bypass control valve (BCV) group 100 comprises the Pilot operated check valve 110 and second back pressure apparatus particularly.The entry end of Pilot operated check valve 110 is connected with the entry end of second back pressure apparatus, the outlet end of Pilot operated check valve 110 is connected with the control mouth K1 of cartridge valve, the control mouth K2 of Pilot operated check valve 110 is that the 3rd end of bleed off circuit 85 is connected with first control end of selector valve 40, promptly the rod chamber oil-feed control oil channel 86 with control selector valve 40 is connected, and the outlet end of second back pressure apparatus is connected with the outlet end T1 of cartridge valve 130.Above bypass control valve (BCV) group 100 utilizes the original rod chamber oil-feed of hydraulic control system control oil channel 86 to control, and structure and control procedure are simple, and reliable performance is with low cost.
Wherein, second back pressure apparatus of present embodiment is in particular relief valve 120.In addition, also can substitute this relief valve 120 with back pressure valve.
Below in conjunction with Fig. 2 the working principle of the hydraulic control system of present embodiment is described.
When selector valve 40 is in as shown in Figure 2 the position, rod chamber oil-feed control oil channel 86 and rodless cavity oil-feed control oil channel 87 are passive state, selector valve 40 is in meta, pressure hydraulic fluid port P, the oil drain out T of selector valve 40, the first actuator port A and the second actuator port B disconnect, and pressure oil directly flows back to fuel tank 10 by the 3rd actuator port and the 4th actuator port of selector valve 40.Simultaneously, because the control mouth K2 of the Pilot operated check valve 110 that is connected with rod chamber oil-feed control oil channel 86 does not have pressure, Pilot operated check valve 110 is in unidirectional on state, therefore, the hydraulic oil of the control mouth K1 of cartridge valve 130 can't flow out by Pilot operated check valve 110, thereby cartridge valve 130 is in off state.At this moment, the rod chamber 72 of oil cylinder 70 and rodless cavity 71 are discharged because of no hydraulic oil and are kept original pressure, and oil cylinder 70 keeps original position.
Make rod chamber 72 oil-feeds of oil cylinder 70, give rod chamber oil-feed control oil channel 86 flows and form pressure by the handle signal, the final spool 41 that promotes selector valve 40 moves down, the rod chamber 72 of oil cylinder 70 is communicated, the rod chamber 72 that fluid enters oil cylinder 70 by variable displacement pump 20 through the pressure hydraulic fluid port P and the first actuator port A of selector valve 40 by pressure oil circuit 81 with variable displacement pump 20.
In rod chamber 72 oil-feeds and during rodless cavity 71 oil returns, the rodless cavity 71 of oil cylinder 70 can be divided into two passages and flow back to fuel tank 10 under the situation of return oil pressure greater than the setting pressure of the relief valve 120 of bypass control valve (BCV) group 100.Passage is to flow back to fuel tank 10 through the second actuator port B of selector valve 40 and oil drain out T and back pressure valve 50 in two passages; Another passage is to flow back to fuel tank 10 by bleed off circuit 85.Because the control mouth K2 of the Pilot operated check valve 110 that is connected with rod chamber oil-feed control oil channel 86 is in pressure condition is arranged, therefore, Pilot operated check valve 110 is in the two-way admittance state, the setting pressure that whether cartridge valve 130 is opened by relief valve 120 in the bypass control valve (BCV) group 100 determines at this moment, if the return oil pressure of oil cylinder 70 reaches the setting pressure of relief valve 120, then cartridge valve 130 is connected entry end P1 and outlet end T1 because of the pressure (being return oil pressure) of entry end P1 greater than the pressure (being the setting pressure of relief valve 120) of control mouthful K1, thereby can be by bleed off circuit 85 to fuel tank 10 oil extractions.
In rod chamber 72 oil-feeds and during rodless cavity 71 oil returns, the rodless cavity 71 of oil cylinder 70 is less than or equal at return oil pressure under the situation of setting pressure of relief valve 120 of bypass control valve (BCV) group 100, because the pressure of the entry end P1 of cartridge valve 130 does not reach the pressure of control mouthful K1, cartridge valve 130 in the bypass control valve (BCV) group 100 still is in off state, thereby oil cylinder 70 is only by back pressure valve 50 oil returns.
Make rodless cavity 71 oil-feeds of oil cylinder 70, then give rodless cavity oil-feed control oil channel 87 flows and form pressure by the handle signal, the final promotion moved on the selector valve 40, the rodless cavity 71 of oil cylinder 70 is communicated with variable displacement pump 20, and fluid enters in the rodless cavity 71 of oil cylinder 70 by the pressure hydraulic fluid port P and the second actuator port B of variable displacement pump 20 through selector valve 40.Simultaneously, the rod chamber 72 of oil cylinder 70 flows back to fuel tank 10 through the first actuator port A and the oil drain out T of selector valve 40 through back pressure valve 50.
In rodless cavity 71 oil-feeds and during rod chamber 72 oil returns, owing to do not have pressure in the rod chamber oil-feed control oil channel 86, the control mouth K2 of the Pilot operated check valve 110 that is connected with rod chamber oil-feed control oil channel 86 does not have pressure yet, Pilot operated check valve 110 can only unidirectional conducting, the control mouth K1 of the cartridge valve 130 in the bypass control valve (BCV) group 100 and relief valve 120 can not conductings, thereby the cartridge valve 130 of bypass control valve (BCV) group 100 is in off state, so bleed off circuit 85 disconnects.Therefore oil cylinder 70 is only by back pressure valve 50 oil returns.
Among the above embodiment, the setting pressure of the relief valve 120 of bypass control valve (BCV) group 100 is adjustable, can set according to the difference of the working state of oil cylinder 70.The flow of cartridge valve 130 also can change according to the difference of the required oil return flow of oil cylinder 70, to adapt to engineering machinery operating modes complicated and changeable such as excavator.And when engineering machinery was not worked, the bypass control valve (BCV) group 100 of present embodiment can be used as the load maintaining valve and use, and can make oil cylinder 70 keep original position for a long time.
As can be seen from the above description, the utility model the above embodiments have realized following technique effect:
The bleed off circuit that has the bypass control valve (BCV) group by setting, when rod chamber oil-feed rodless cavity oil return and return oil pressure reach the oil pressure relief that the bypass control valve (BCV) group sets, fluid flows back to fuel tank by selector valve through oil extraction oil circuit and bleed off circuit two-way respectively, thereby guarantee that back pressure is within ideal range, make motor reduce oil consumption, improve the working efficiency of excavator.
The bypass control valve (BCV) group utilizes the original rod chamber oil-feed of hydraulic control system control oil channel to control, and structure and control procedure are simple, and reliable performance is with low cost.
Because the oil pressure relief of bypass control valve (BCV) group is adjustable, can make the return oil pressure of the rodless cavity of oil cylinder regulate more flexible and changeable.
When engineering machinery was not worked, the Pilot operated check valve of hydraulic control system can make the long pressurize of the rodless cavity of oil cylinder, and the bypass control valve (BCV) group can be used as the load maintaining valve and use, and makes oil cylinder keep original position for a long time.
The above is a preferred embodiment of the present utility model only, is not limited to the utility model, and for a person skilled in the art, the utility model can have various changes and variation.All within spirit of the present utility model and principle, any modification of being done, be equal to replacement, improvement etc., all should be included within the protection domain of the present utility model.

Claims (6)

1. hydraulic control system, comprise oil cylinder (70), selector valve (40), pressure oil circuit (81), oil extraction oil circuit (82), first working oil path (83) and second working oil path (84), described selector valve (40) comprises pressure hydraulic fluid port (P), oil drain out (T), first actuator port (A) and second actuator port (B), described pressure hydraulic fluid port (P) is connected with described pressure oil circuit (81), described oil drain out (T) is connected with described oil extraction oil circuit (82), described first actuator port (A) is connected with the rod chamber (72) of described oil cylinder (70) by described first working oil path (83), described second actuator port (B) is connected with the rodless cavity (71) of described oil cylinder (70) by described second working oil path (84), described oil extraction oil circuit (82) comprises serial connection first back pressure apparatus thereon, and the entry end of described first back pressure apparatus is connected with described oil drain out (T), it is characterized in that, described hydraulic control system also comprises bleed off circuit (85), first end of described bleed off circuit (85) is connected with described second working oil path (84), second end of described bleed off circuit (85) is connected with the outlet end of described first back pressure apparatus, and described bleed off circuit (85) comprises the bypass control valve (BCV) group (100) of control described bleed off circuit (85) break-make.
2. hydraulic control system according to claim 1, it is characterized in that, described bypass control valve (BCV) group (100) comprises cartridge valve (130) that is serially connected with on the described bleed off circuit (85) and the cartridge valve control valve group of controlling described cartridge valve (130) break-make, the entry end (P1) of described cartridge valve (130) is connected with described second working oil path (84), the outlet end (T1) of described cartridge valve (130) is connected with the outlet end of described first back pressure apparatus, and the control end (K1) of described cartridge valve (130) is connected with described cartridge valve control valve group.
3. hydraulic control system according to claim 2 is characterized in that,
Described hydraulic control system also comprises rod chamber oil-feed control oil channel (86), and described rod chamber oil-feed control oil channel (86) is used to control described selector valve (40) and changes valve position, so that described rod chamber (72) oil-feed of described oil cylinder (70);
Described cartridge valve control valve group comprises the Pilot operated check valve (110) and second back pressure apparatus, the entry end of described Pilot operated check valve (110) is connected with the entry end of described second back pressure apparatus, the outlet end of described Pilot operated check valve (110) is connected with the control mouth (K1) of described cartridge valve, the control mouth (K2) of described Pilot operated check valve (110) is connected with described rod chamber oil-feed control oil channel (86), and the outlet end of described second back pressure apparatus is connected with the outlet end (T1) of described cartridge valve (130).
4. hydraulic control system according to claim 3 is characterized in that, described second back pressure apparatus is relief valve (120) or back pressure valve.
5. an engineering machinery comprises hydraulic control system, it is characterized in that, described hydraulic control system is according to each described hydraulic control system in the claim 1 to 4.
6. engineering machinery according to claim 5 is characterized in that, described engineering machinery is an excavator.
CN 201320060600 2013-02-01 2013-02-01 Hydraulic control system and engineering machine Expired - Lifetime CN203081878U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN 201320060600 CN203081878U (en) 2013-02-01 2013-02-01 Hydraulic control system and engineering machine

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Application Number Priority Date Filing Date Title
CN 201320060600 CN203081878U (en) 2013-02-01 2013-02-01 Hydraulic control system and engineering machine

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CN203081878U true CN203081878U (en) 2013-07-24

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CN 201320060600 Expired - Lifetime CN203081878U (en) 2013-02-01 2013-02-01 Hydraulic control system and engineering machine

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109202170A (en) * 2018-11-15 2019-01-15 长沙思胜智能设备有限公司 The main hydraulic system and broaching machine of broaching machine
CN109469657A (en) * 2018-12-26 2019-03-15 江苏徐工工程机械研究院有限公司 Hydraulic system and trepan
CN111503074A (en) * 2020-04-27 2020-08-07 成都锐达自动控制有限公司 Unit rapid door closing hydraulic control valve block with self-holding function and control method

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109202170A (en) * 2018-11-15 2019-01-15 长沙思胜智能设备有限公司 The main hydraulic system and broaching machine of broaching machine
CN109469657A (en) * 2018-12-26 2019-03-15 江苏徐工工程机械研究院有限公司 Hydraulic system and trepan
CN109469657B (en) * 2018-12-26 2024-02-02 江苏徐工工程机械研究院有限公司 Hydraulic system and drilling machine
CN111503074A (en) * 2020-04-27 2020-08-07 成都锐达自动控制有限公司 Unit rapid door closing hydraulic control valve block with self-holding function and control method

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Granted publication date: 20130724