CN205446237U - Hydraulic pump control ware - Google Patents
Hydraulic pump control ware Download PDFInfo
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- CN205446237U CN205446237U CN201620124692.5U CN201620124692U CN205446237U CN 205446237 U CN205446237 U CN 205446237U CN 201620124692 U CN201620124692 U CN 201620124692U CN 205446237 U CN205446237 U CN 205446237U
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Abstract
The utility model relates to a hydraulic pump control ware, it includes the hydraulic pump, electromagnetism ratio pressure reducing valve, discharge capacity control two -position three way valve, hyperbola power control two -position three way valve, pressure cuts off the two -position three way valve, the sensitive two -position three way valve of load, it increases the sensitive two -position three way valve of load on the basis of three current function control devices, one of them import of the sensitive two -position three way valve of this load concatenates in discharge capacity control delivery line with the export, another import is through sensitive inlet line of load and main pump outlet pressure tube coupling, the case both sides of this valve respectively with sensitive hydraulic pressure signal pipe way of load and main pump outlet pressure tube coupling. The utility model discloses a sensitive signal of load can the control pump discharge capacity the change, realize providing the hydraulic pressure flow according to the load demand, avoid system's spill losses, realized energy -conserving purpose, possess electromagnetism proportional control, the sensitive control of load, hyperbola power limitation and pressure turnout function simultaneously to control for under the different work condition facilitates.
Description
Technical field
This utility model relates to hydraulic pump discharge control field, a kind of hydraulic pump control device.
Background technology
In the displacement control technology of hydraulic pump, mainly there are the control of electric proportional control, hyperbola power, Ioad-sensing control and pressure cut off to control four kinds and control functions.And current hydraulic pump control device mainly has two kinds, one is integrated electric proportional control, hyperbola power controls and pressure cut off controls three kinds of functions, one is that integrated electric proportional control, Ioad-sensing control and pressure cut off control function, does not has controller can be provided simultaneously with whole four kinds of functions.
Such as woods moral product E TP controller, it has electric proportional control, hyperbola power controls and pressure cut off controls three kinds of functions, as shown in Figure 1, this controller includes that the hydraulic pump 1 being made up of main pump 101 and variable oil cylinder 102, solenoid-operated proportional air relief valve 4, displacement control two position three-way valve 3, hyperbola power control two position three-way valve 6 and pressure cut off two position three-way valve 8 to concrete structural representation.Wherein:
Main pump outlet pressure piping a all has with the entrance of aforementioned four valve and the L mouth of variable oil cylinder and is connected；
Solenoid-operated proportional air relief valve 4 is for singly entering singly to go out valve, and its import is connected by decompression intake line k and main pump outlet pressure piping a, and decompression output pipe b is drawn in its outlet；
Displacement control two position three-way valve 3 enters one for hydraulic control two and goes out valve, one of them import is by displacement control inlet ductwork o is connected with main pump outlet pressure piping a, another import is connected with fuel tank, its outlet is upper draws displacement control output pipe d, the wherein side of its spool connects decompression output pipe b, opposite side connects spring and position feedback rod, and position feedback rod is connected with the piston rod of variable oil cylinder；
Hyperbola Power Limitation two position three-way valve 6 enters one for Mechanical course two and goes out valve, one of them import is connected with main pump outlet pressure piping a by hyperbola Power Limitation intake line g, another import connects decompression output pipe b, the upper hyperbola Power Limitation output pipe e that draws of its outlet, piston 7 is connected, the other end connects the first slide block 9 with power control in wherein one end of its spool；Wherein, the first slide block 9 forms equalising torque structure with lever the 10, second slide block 11, and lever 10 wherein one end is hinged, and two slide blocks can slide along lever 10 surface, and the second slide block 11 is connected with position feedback rod 12；Power controls two hydraulic fluid ports of piston 7 and is respectively Z1 mouth and Z2 mouth, and these two mouths can leave unused and not connect, or connect with other hydraulic control oil sources.
Pressure cut off two position three-way valve 8 enters one for hydraulic control two and goes out valve, one of them import is connected with main pump outlet pressure piping a by pressure cut off inlet ductwork h, another import connects hyperbola Power Limitation output pipe e, pressure cut off output pipe f is drawn in its outlet, pressure cut off output pipe f is connected with the R mouth of variable oil cylinder, and wherein one end of its spool is connected with main pump outlet pressure piping a by pressure cut off control piper i.
Below the operation principle of aforementioned controllers is simply introduced.
Solenoid-operated proportional air relief valve 4 under the control of electric current, the pressure at control piper b, the size of pressure at pipeline b, control the aperture of two position three-way valve 3, thus change the pressure of pipeline d.
After pressure at pipeline i arrives greatly a certain numerical value, pressure cut off two position three way directional control valve 8 will move up, pipeline h communicates with pipeline f, make variable oil cylinder 102 left and right sides pressure equal, and the area of R side is bigger, therefore pump delivery diminishes, and the output flow of pump reduces, it is achieved that pressure cut off function.
First slide block 9 and the second slide block 11 can slide along the surface of lever 10.At lever 10, around center of rotation, the active force of the first slide block 9 and the second slide block 11 has the relation of equalising torque, meets formula；Pn×An×L11=Fm×L9.Wherein, L11It is second slide block 11 distance to lever 10 centre of gyration, L9It it is first slide block 9 distance to lever 10 centre of gyration.FmThe power that piston 7 is applied, mainly spring force and Z1 mouth and the pressure of Z2 is controlled by power.
The output of pump is calculated by following formula:(P in formulanRepresent second slide block 11 pressure at the n of bottom；Q represents the output flow of pump；N represents that rotating speed, const represent constant, namely the output of pump is steady state value；Because L11Proportional to pump delivery, so using L11Size represent pump delivery).
Due to pump delivery and L11Proportional, therefore work as FmDuring for definite value, the output of hydraulic pump is steady state value.Thus achieve constant power output.
The pressure of pipeline b is proportional to the electrical current of solenoid-operated proportional air relief valve 4, and thus the pressure on the right side of the pressure of pipeline d, the pressure of pipeline e, the pressure of pipeline f, variable oil cylinder 102 is all proportional to the electrical current of solenoid-operated proportional air relief valve 4.Therefore, in the case of the holding of miscellaneous part state is constant, by controlling the electrical current of solenoid-operated proportional air relief valve 4, the ratio that gets final product controls the discharge capacity of main pump 101.
Controller noted above does not has Ioad-sensing control function, is not suitable for load-sensitive excavator hydraulic system, and function is restricted.
Utility model content
The technical problems to be solved in the utility model is to provide a kind of electric proportional control, the control of hyperbola power, Ioad-sensing control and pressure cut off of being provided simultaneously with and controls four kinds of hydraulic pump control devices controlling functions.
For solving above-mentioned technical problem, hydraulic pump control device of the present utility model includes that hydraulic pump, solenoid-operated proportional air relief valve, displacement control two position three-way valve, hyperbola power control two position three-way valve and pressure cut off two position three-way valve, wherein, hydraulic pump is made up of main pump and variable oil cylinder, and main pump is drawn main pump outlet pressure piping；The import of solenoid-operated proportional air relief valve is connected with main pump outlet pressure piping by decompression intake line, and decompression output pipe is drawn in its outlet；Displacement control two position three-way valve is by displacement control inlet ductwork is connected with main pump outlet pressure piping, another import is connected with fuel tank, and its outlet is upper draws displacement control output pipe；One import of hyperbola Power Limitation two position three-way valve is connected with main pump outlet pressure piping by hyperbola Power Limitation intake line, another import connects decompression output pipe, and its outlet is upper draws hyperbola Power Limitation output pipe；One import of pressure cut off two position three-way valve is connected with main pump outlet pressure piping by pressure cut off inlet ductwork, another import connects hyperbola Power Limitation output pipe, pressure cut off output pipe is drawn in its outlet, it is structurally characterized in that this controller also includes load-sensitive two position three-way valve, this load-sensitive two position three-way valve is that hydraulic control two is entered one and gone out valve, and one of them import is serially connected in outlet in displacement control output pipe, another import is connected with main pump outlet pressure piping by load-sensitive entrance pipe；The spool of this load-sensitive two position three-way valve wherein side is connected with load-sensitive hydraulic pressure signal pipeline, opposite side is connected with main pump outlet pressure piping by Ioad-sensing control pipeline.
The beneficial effects of the utility model are: 1) can be controlled the change of pumpage by load-sensitive signal, it is achieved provide hydraulic flow by loading demand, it is to avoid system spill losses, it is achieved that energy-conservation；2) it is provided simultaneously with solenoid-operated proportional control, Ioad-sensing control, hyperbola Power Limitation and pressure cut off function, provides convenient for the control under different operating modes.
Accompanying drawing explanation
With detailed description of the invention, this utility model is described in further detail below in conjunction with the accompanying drawings:
Fig. 1 is the structural principle schematic diagram of prior art controller；
Fig. 2 is structural principle schematic diagram of the present utility model.
Detailed description of the invention
Fig. 1 is woods moral product E TP controller, it has electric proportional control, hyperbola power controls and pressure cut off controls three kinds of functions, and this controller includes that the hydraulic pump 1 being made up of main pump 101 and variable oil cylinder 102, solenoid-operated proportional air relief valve 4, displacement control two position three-way valve 3, hyperbola power control two position three-way valve 6 and pressure cut off two position three-way valve 8.
Main pump outlet pressure piping a all has with the entrance of aforementioned four valve and the L mouth of variable oil cylinder and is connected.
Solenoid-operated proportional air relief valve 4 is for singly entering singly to go out valve, and its import is connected by decompression intake line k and main pump outlet pressure piping a, and decompression output pipe b is drawn in its outlet.
Displacement control two position three-way valve 3 enters one for hydraulic control two and goes out valve, one of them import is by displacement control inlet ductwork o is connected with main pump outlet pressure piping a, another import is connected with fuel tank, its outlet is upper draws displacement control output pipe d, the wherein side of its spool connects decompression output pipe b, opposite side connects spring and position feedback rod, and position feedback rod is connected with the piston rod of variable oil cylinder.
Hyperbola Power Limitation two position three-way valve 6 enters one for Mechanical course two and goes out valve, one of them import is connected with main pump outlet pressure piping a by hyperbola Power Limitation intake line g, another import connects decompression output pipe b, the upper hyperbola Power Limitation output pipe e that draws of its outlet, piston 7 is connected, the other end connects the first slide block 9 with power control in wherein one end of its spool；Wherein, the first slide block 9 forms equalising torque structure with lever the 10, second slide block 11, and lever 10 wherein one end is hinged, and two slide blocks can slide along lever 10 surface, and the second slide block 11 is connected with position feedback rod 12；Power controls two hydraulic fluid ports of piston 7 and is respectively Z1 mouth and Z2 mouth, and these two mouths can leave unused and not connect, or connect with other hydraulic control oil sources.
Pressure cut off two position three-way valve 8 enters one for hydraulic control two and goes out valve, one of them import is connected with main pump outlet pressure piping a by pressure cut off inlet ductwork h, another import connects hyperbola Power Limitation output pipe e, pressure cut off output pipe f is drawn in its outlet, pressure cut off output pipe f is connected with the R mouth of variable oil cylinder, and wherein one end of its spool is connected with main pump outlet pressure piping a by pressure cut off control piper i.
Below the operation principle of three kinds of functions of aforementioned woods moral product E TP controller is simply introduced.
Solenoid-operated proportional air relief valve 4 under the control of electric current, the pressure at control piper b, the size of pressure at pipeline b, control the aperture of two position three-way valve 3, thus change the pressure of pipeline d.
After pressure at pipeline i arrives greatly a certain numerical value, pressure cut off two position three way directional control valve 8 will move up, pipeline h communicates with pipeline f, make variable oil cylinder 102 left and right sides pressure equal, and the area of R side is bigger, therefore pump delivery diminishes, and the output flow of pump reduces, it is achieved that pressure cut off function.
First slide block 9 and the second slide block 11 can slide along the surface of lever 10.At lever 10, around center of rotation, the active force of the first slide block 9 and the second slide block 11 has the relation of equalising torque, meets formula；Pn×An×L11=Fm×L9.Wherein, L11It is second slide block 11 distance to lever 10 centre of gyration, L9It it is first slide block 9 distance to lever 10 centre of gyration.FmThe power that piston 7 is applied, mainly spring force and Z1 mouth and the pressure of Z2 is controlled by power.
The output of pump is calculated by following formula:(P in formulanRepresent second slide block 11 pressure at the n of bottom；Q represents the output flow of pump；N represents that rotating speed, const represent constant, namely the output of pump is steady state value；Because L11Proportional to pump delivery, so using L11Size represent pump delivery).
Due to pump delivery and L11Proportional, therefore work as FmDuring for definite value, the output of hydraulic pump is steady state value.Thus achieve constant power output.
The pressure of pipeline b is proportional to the electrical current of solenoid-operated proportional air relief valve 4, and thus the pressure on the right side of the pressure of pipeline d, the pressure of pipeline e, the pressure of pipeline f, variable oil cylinder 102 is all proportional to the electrical current of solenoid-operated proportional air relief valve 4.Therefore, in the case of the holding of miscellaneous part state is constant, by controlling the electrical current of solenoid-operated proportional air relief valve 4, the ratio that gets final product controls the discharge capacity of main pump 101.
Fig. 2 is improvement project of the present utility model, and it is on the basis of Fig. 1, integrated load-sensitive functional module, it is achieved pump can carry out variable according to load-sensitive signal.As in figure 2 it is shown, hydraulic pump control device of the present utility model includes that hydraulic pump 1, solenoid-operated proportional air relief valve 4, displacement control two position three-way valve 3, hyperbola power control two position three-way valve 6 and pressure cut off two position three-way valve 8.Wherein, hydraulic pump 1 is made up of main pump 101 and variable oil cylinder 102, and main pump 101 is drawn main pump outlet pressure piping a；The import of solenoid-operated proportional air relief valve 4 is connected with main pump outlet pressure piping a by decompression intake line k, and decompression output pipe b is drawn in its outlet；Displacement control two position three-way valve 3 is by displacement control inlet ductwork o is connected with main pump outlet pressure piping a, another import is connected with fuel tank, and its outlet is upper draws displacement control output pipe d；One import of hyperbola Power Limitation two position three-way valve 6 is connected with main pump outlet pressure piping a by hyperbola Power Limitation intake line g, another import connects decompression output pipe b, and its outlet is upper draws hyperbola Power Limitation output pipe e；One import of pressure cut off two position three-way valve 8 is connected with main pump outlet pressure piping a by pressure cut off inlet ductwork h, another import connects hyperbola Power Limitation output pipe e, pressure cut off output pipe f is drawn in its outlet, controller of the present utility model also includes load-sensitive two position three-way valve 5, this load-sensitive two position three-way valve 5 enters one for hydraulic control two and goes out valve, and one of them import is serially connected in outlet in displacement control output pipe d, another import is connected with main pump outlet pressure piping a by load-sensitive entrance pipe j；The spool of this load-sensitive two position three-way valve 5 wherein side is connected with load-sensitive hydraulic pressure signal pipeline LS, opposite side is connected with main pump outlet pressure piping a by Ioad-sensing control pipeline m.
As shown in Figure 2, load-sensitive two position three-way valve 5 is connected with main pump outlet pressure piping a by one of them load-sensitive entrance pipe j, for convenience of description, as shown in Figure 2, another load-sensitive entrance pipe c of definition load-sensitive two position three-way valve 5, it is connected with the outlet of displacement control two position three-way valve 3 by another load-sensitive entrance pipe c, thus load-sensitive two position three-way valve 5 is serially connected on displacement control output pipe d.The outlet of load-sensitive two position three-way valve 5 connects the entrance of Power Limitation two position three-way valve 6.Hydraulic pump outlet pressure, successively through pipeline a-> o-> c-> d-> e-> f, reaches the R side of variable oil cylinder 102, forms series loop.Solenoid-operated proportional air relief valve 4, load-sensitive two position three-way valve 5, hyperbolic power control two position three-way valve 6, pressure cut off two position three-way valve 8 all can realize the control to pump 101 discharge capacity.
When LS pressure increases, the circulation area of pipeline c and pipeline d increases, and the pressure of pipeline d reduces, and the R lateral pressure of variable oil cylinder 102 reduces, and pump delivery increases.When LS pressure reduces, load-sensitive two position three-way valve 5 moves up under the effect of pipeline m pressure, and the circulation area of pipeline j and pipeline d increases, and the pressure of pipeline d raises, and the R lateral pressure of variable oil cylinder 102 raises, and pump delivery reduces.It is achieved in pump delivery to increase along with the rising of load-sensitive signal LS, reduces along with the reduction of LS, it is achieved Ioad-sensing control function.
In sum, this utility model can control the change of pumpage by load-sensitive signal, it is achieved provides hydraulic flow by loading demand, it is to avoid system spill losses, it is achieved that energy-conservation purpose.It addition, this utility model is provided simultaneously with solenoid-operated proportional control, Ioad-sensing control, hyperbola Power Limitation and pressure cut off function, thus provide convenient for the control under different operating modes.
In sum, this utility model is not limited to above-mentioned detailed description of the invention.Those skilled in the art, on the premise of without departing from spirit and scope of the present utility model, can do some changes and modification.Protection domain of the present utility model should be as the criterion with claim of the present utility model.
Claims (1)
1. a hydraulic pump control device, two position three-way valve (6) and pressure cut off two position three-way valve (8) is controlled including hydraulic pump (1), solenoid-operated proportional air relief valve (4), displacement control two position three-way valve (3), hyperbola power, wherein, hydraulic pump (1) is made up of main pump (101) and variable oil cylinder (102), and main pump (101) is upper draws main pump outlet pressure piping (a)；The import of solenoid-operated proportional air relief valve (4) is connected with main pump outlet pressure piping (a) by decompression intake line (k), and decompression output pipe (b) is drawn in its outlet；Displacement control two position three-way valve (3) is by displacement control inlet ductwork (o) is connected with main pump outlet pressure piping (a), another import is connected with fuel tank, and its outlet is upper draws displacement control output pipe (d)；One import of hyperbola Power Limitation two position three-way valve (6) is connected with main pump outlet pressure piping (a) by hyperbola Power Limitation intake line (g), another import connects decompression output pipe (b), and its outlet is upper draws hyperbola Power Limitation output pipe (e)；One import of pressure cut off two position three-way valve (8) is connected with main pump outlet pressure piping (a) by pressure cut off inlet ductwork (h), another import connects hyperbola Power Limitation output pipe (e), pressure cut off output pipe (f) is drawn in its outlet, it is characterized in that this controller also includes load-sensitive two position three-way valve (5), this load-sensitive two position three-way valve (5) is that hydraulic control two is entered one and gone out valve, one of them import and outlet are serially connected in displacement control output pipe (d), another import is connected with main pump outlet pressure piping (a) by load-sensitive entrance pipe (j)；The spool wherein side of this load-sensitive two position three-way valve (5) is connected with load-sensitive hydraulic pressure signal pipeline (LS), opposite side is connected with main pump outlet pressure piping (a) by Ioad-sensing control pipeline (m).
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| CN201620124692.5U CN205446237U (en) | 2016-02-17 | 2016-02-17 | Hydraulic pump control ware |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106523457A (en) * | 2016-11-22 | 2017-03-22 | 天津海安科技有限公司 | Electric hydraulic control mechanism |
| CN106593969A (en) * | 2016-11-22 | 2017-04-26 | 天津海安科技有限公司 | Electric hydraulic control mechanism |
| CN106640798A (en) * | 2016-11-22 | 2017-05-10 | 天津海安科技有限公司 | Electro-hydraulic control mechanism capable of adjusting pressure and unloading |
| CN106640575A (en) * | 2016-11-22 | 2017-05-10 | 天津苑博科技有限公司 | Electric hydraulic control mechanism |
| CN106762926A (en) * | 2016-11-22 | 2017-05-31 | 天津海安科技有限公司 | Pressure-adjustable and the electrohydraulic controlling mechanism of off-load |
| CN107237785A (en) * | 2017-07-25 | 2017-10-10 | 江苏谷登工程机械装备有限公司 | A kind of pressure cut off control system of external enclosed pump |
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2016
- 2016-02-17 CN CN201620124692.5U patent/CN205446237U/en active Active
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106523457A (en) * | 2016-11-22 | 2017-03-22 | 天津海安科技有限公司 | Electric hydraulic control mechanism |
| CN106593969A (en) * | 2016-11-22 | 2017-04-26 | 天津海安科技有限公司 | Electric hydraulic control mechanism |
| CN106640798A (en) * | 2016-11-22 | 2017-05-10 | 天津海安科技有限公司 | Electro-hydraulic control mechanism capable of adjusting pressure and unloading |
| CN106640575A (en) * | 2016-11-22 | 2017-05-10 | 天津苑博科技有限公司 | Electric hydraulic control mechanism |
| CN106762926A (en) * | 2016-11-22 | 2017-05-31 | 天津海安科技有限公司 | Pressure-adjustable and the electrohydraulic controlling mechanism of off-load |
| CN106640575B (en) * | 2016-11-22 | 2018-11-16 | 建湖县恒昌液压机械有限公司 | Electrohydraulic controlling mechanism |
| CN106593969B (en) * | 2016-11-22 | 2019-01-08 | 佛山金华信智能科技有限公司 | Electrohydraulic controlling mechanism |
| CN106762926B (en) * | 2016-11-22 | 2019-05-10 | 南通华德锻压机床有限公司 | The electrohydraulic controlling mechanism of pressure-adjustable and off-load |
| CN106523457B (en) * | 2016-11-22 | 2019-05-10 | 天嘉智能装备制造江苏股份有限公司 | Electrohydraulic controlling mechanism |
| CN106640798B (en) * | 2016-11-22 | 2019-05-31 | 南京汇强机械设备有限公司 | The electrohydraulic controlling mechanism of pressure-adjustable and off-load |
| CN107237785A (en) * | 2017-07-25 | 2017-10-10 | 江苏谷登工程机械装备有限公司 | A kind of pressure cut off control system of external enclosed pump |
| CN107237785B (en) * | 2017-07-25 | 2019-03-12 | 江苏谷登工程机械装备有限公司 | A kind of pressure cut off control system of external enclosed pump |
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