A speed stabilization control system for traveling hydraulic pump

Abstract

The present invention discloses a running hydraulic pump speed stabilization control system, comprising a first running hydraulic pump oil circuit block, a second running hydraulic pump oil circuit block, and a control valve group; the first running hydraulic pump oil circuit block and the second running hydraulic pump oil circuit block respectively comprise two working oil ports and a running hydraulic pump variable control mechanism, and the input end of the control valve group is connected to the working oil port of the first running hydraulic pump oil circuit block / the second running hydraulic pump oil circuit block, and the output end of the control valve group is connected to the running hydraulic pump variable control mechanism; when the vehicle is starting, accelerating or moving at a constant speed, the control valve group is not connected; when the vehicle is braking or going downhill, the control pressure oil enters the corresponding running hydraulic pump variable control mechanism to intervene in its displacement change. The running hydraulic pump speed stabilization control system provided by the present invention stabilizes the hydraulic pump speed by intervening in the displacement of the hydraulic pump through the control valve group when the vehicle is braking or going downhill, thereby achieving the purpose of stabilizing the engine speed.

Description

Technical Field

[0001] The invention relates to the technical field of railway engineering machinery, and in particular to a speed stabilization control system for a running hydraulic pump. Background Art

[0002] Hydraulic systems are widely used in vehicle travel due to their compact structure, easy layout, good control performance, good low-speed stability, and easy to achieve stepless speed change. However, due to the large inertia and high speed of railway engineering machinery vehicles, and the long downhill distance of the track line, there is a problem of the hydraulic pump being reversely dragged during braking or downhill, resulting in unstable engine speed. Especially when the engine drives the generator at the same time, the problem of the generator set tripping and stopping due to speed instability is particularly prominent.

[0003] In view of this, it is necessary to provide a travel hydraulic pump speed stabilization control system to solve the above technical problems. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a running hydraulic pump speed stabilization control system, which stabilizes the hydraulic pump speed by intervening in the displacement of the hydraulic pump through the control valve group when the vehicle is braking or going downhill, thereby achieving the purpose of stabilizing the engine speed.

[0005] In order to solve the above problems, the technical solution of the present invention is as follows:

[0006] A travel hydraulic pump speed stabilization control system, comprising a first travel hydraulic pump oil circuit block, a second travel hydraulic pump oil circuit block, and a control valve group; the first travel hydraulic pump oil circuit block and the second travel hydraulic pump oil circuit block respectively comprise two working oil ports and a travel hydraulic pump variable control mechanism, and the input end of the control valve group is connected to the working oil port of the first travel hydraulic pump oil circuit block / the second travel hydraulic pump oil circuit block, and the output end of the control valve group is connected to the travel hydraulic pump variable control mechanism;

[0007] The control valve group includes a first control circuit and a second control circuit respectively connected to one of the working oil ports of the first running hydraulic pump oil circuit block and the second running hydraulic pump oil circuit block, a third control circuit and a fourth control circuit respectively connected to the other working oil ports of the first running hydraulic pump and the second running hydraulic pump oil circuit block, and a control pressure setting circuit; the output ends of the first control circuit, the second control circuit, the third control circuit and the fourth control circuit are respectively connected to the corresponding running hydraulic pump variable control mechanism;

[0008] The first control circuit includes a first one-way valve, a first throttle valve, a first solenoid valve, a first overflow valve, and a second one-way valve connected in sequence from the input end to the output end;

[0009] The second control loop is formed by sequentially connecting a third one-way valve, a first throttle valve, a first solenoid valve, a first overflow valve and a fourth one-way valve;

[0010] The third control circuit includes a fifth one-way valve, a second throttle valve, a second solenoid valve, a second overflow valve, and a sixth one-way valve connected in sequence from the input end to the output end;

[0011] The fourth control loop is formed by sequentially connecting the seventh one-way valve, the second throttle valve, the second solenoid valve, the second overflow valve and the eighth one-way valve;

[0012] The control pressure setting circuit includes a shuttle valve and a third relief valve; the shuttle valve includes three oil ports, one of which is connected between the first relief valve and the second check valve of the first control circuit, and is also connected between the first relief valve and the fourth check valve of the second control circuit, another oil port is connected between the second relief valve and the sixth check valve of the third control circuit, and is also connected between the second relief valve and the eighth check valve of the fourth control circuit, and the third oil port is connected to the third relief valve;

[0013] When the vehicle is starting, accelerating or moving at a constant speed, the first solenoid valve and the second solenoid valve are energized and the control valve group is not connected; when the vehicle is braking or going downhill, the first solenoid valve / the second solenoid valve is de-energized according to the running direction, and the corresponding control circuit is connected, and the control pressure oil enters the corresponding running hydraulic pump variable control mechanism to intervene in its displacement change, thereby controlling the engine speed of the first running hydraulic pump / the second running hydraulic pump.

[0014] Furthermore, the control pressures of the first control loop, the second control loop, the third control loop and the fourth control loop are set by a third relief valve, and a pressure setting value of the third relief valve is lower than setting values ​​of the first relief valve and the second relief valve.

[0015] Furthermore, the control valve group is of integrated design.

[0016] Furthermore, each functional valve adopts a threaded cartridge valve.

[0017] Compared with the prior art, the travel hydraulic pump speed stabilization control system provided by the present invention has the following beneficial effects:

[0018] 1. The travel hydraulic pump speed stabilization control system provided by the present invention stabilizes the hydraulic pump speed by intervening in the displacement of the hydraulic pump through the control valve group when the vehicle is braking or going downhill, thereby achieving the purpose of stabilizing the engine speed. The engine speed deviation of the travel hydraulic pump can be controlled within ±50rpm.

[0019] 2. The travel hydraulic pump speed stabilization control system provided by the present invention has an integrated control valve group, and each functional valve adopts a threaded cartridge valve, which has a compact structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some implementation cases of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a schematic diagram of the travel hydraulic pump speed stabilization control system provided by the present invention;

[0022] Figure 2 yes Figure 1 The schematic diagram of the control valve group in the travel hydraulic pump speed stabilization control system shown;

[0023] Figure 3 yes Figure 1 The structural diagram of the control valve group in the running hydraulic pump speed stabilization control system is shown;

[0024] Figure 4 yes Figure 3 A schematic structural diagram of the control valve group from another angle shown;

[0025] Figure 5 yes Figure 3 A schematic structural diagram of the control valve group at a third angle shown;

[0026] Figure 6 yes Figure 3 A schematic structural diagram of the control valve group at a fourth angle is shown. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention and to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the specific implementation modes of the present invention are further described below in conjunction with the accompanying drawings.

[0028] It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as there is no conflict between them.

[0029] This embodiment takes a dual-pump dual-motor system as an example to explain in detail the running hydraulic pump speed stabilization control system of the present application.

[0030] See also Figure 1, is a structural diagram of the running hydraulic pump speed stabilization control system provided by the present invention. The running hydraulic pump speed stabilization control system 100 of the present invention includes a first running hydraulic pump oil circuit block 1, a second running hydraulic pump oil circuit block 2, and a control valve group 3; wherein the first running hydraulic pump oil circuit block 1 includes two working oil ports, respectively denoted as A2 and B2, and a first running hydraulic pump variable control mechanism 13; the second running hydraulic pump oil circuit block 2 includes two working oil ports, respectively denoted as A1 and B1, and a second running hydraulic pump variable control mechanism 23, and the input end of the control valve group 3 is connected to the working oil ports of the first running hydraulic pump oil circuit block 1 / the second running hydraulic pump oil circuit block 2, and the output end of the control valve group 3 is connected to the first running hydraulic pump variable control mechanism 13 / the second running hydraulic pump variable control mechanism 23. In the present invention, the structures of the first running hydraulic pump oil circuit block 1 and the second running hydraulic pump oil circuit block 2 refer to the prior art.

[0031] Please refer to Figures 2 to 6 ,in Figure 2 yes Figure 1 The schematic diagram of the control valve group in the travel hydraulic pump speed stabilization control system shown; Figure 3 yes Figure 1 The structural diagram of the control valve group in the running hydraulic pump speed stabilization control system is shown; Figure 4 yes Figure 3 A schematic structural diagram of the control valve group from another angle shown; Figure 5 yes Figure 3 A schematic structural diagram of the control valve group at a third angle shown; Figure 6 yes Figure 3 The control valve group 3 includes a first control circuit 31 , a second control circuit 32 , a third control circuit 33 , a fourth control circuit 34 , and a control pressure setting circuit 35 .

[0032] The input end of the control valve group 3 is four inlets, which correspond to the four working oil ports of the first running hydraulic pump oil circuit block 1 and the second running hydraulic pump oil circuit block 2, respectively, and are denoted as A1a, A2a, B1a, and B2a. In this embodiment, the inlet A1a of the control valve group 3 is connected to the working oil port A1 of the second running hydraulic pump oil circuit block 2, and the inlet A2a of the control valve group 3 is connected to the working oil port A2 of the first running hydraulic pump oil circuit block 1; the inlet B1a of the control valve group 3 is connected to the working oil port B1 of the second running hydraulic pump oil circuit block 2; and the inlet B2a of the control valve group 3 is connected to the working oil port B2 of the first running hydraulic pump oil circuit block 1.

[0033] The output end of the control valve group 3 is four working oil ports, which serve as the working oil ports of the first control circuit 31, the second control circuit 33, the third control circuit 33 and the fourth control circuit 34 respectively, and are connected to the corresponding running hydraulic pump variable control mechanisms, which are respectively recorded as X1-1, X1-2, X2-1 and X2-2.

[0034] The first control circuit 31 includes a first check valve 311, a first throttle valve 312, a first solenoid valve 313, a first overflow valve 314, and a second check valve 315 which are sequentially connected from the input end to the output end;

[0035] The second control loop 32 is formed by sequentially connecting the third check valve 321, the first throttle valve 312, the first solenoid valve 313, the first overflow valve 314 and the fourth check valve 325;

[0036] The third control circuit 33 includes a fifth check valve 331, a second throttle valve 332, a second solenoid valve 333, a second overflow valve 334, and a sixth check valve 335 which are sequentially connected from the input end to the output end;

[0037] The fourth control circuit 34 is formed by sequentially connecting a seventh check valve 341 , a second throttle valve 332 , a second solenoid valve 333 , a second overflow valve 334 and an eighth check valve 345 .

[0038] The control pressure setting circuit 35 includes a shuttle valve 351 and a third relief valve 352; the shuttle valve 351 includes three oil ports, one of which is connected between the first relief valve 314 and the second non-return valve 315 of the first control circuit 31, and is also connected between the first relief valve 314 and the fourth non-return valve 325 of the second control circuit 32; another oil port is connected between the second relief valve 334 and the sixth non-return valve 335 of the third control circuit 33, and is also connected between the second relief valve 334 and the eighth non-return valve 345 of the fourth control circuit 34; the third oil port is connected to the third relief valve 352; the hydraulic oil overflowing from the first control circuit 31, the second control circuit 32, the third control circuit 33 and the fourth control circuit 34 enters the shuttle valve 351, and then flows back to the hydraulic oil tank through the third relief valve 352 and the return oil pipeline.

[0039] The control pressures of the first control loop 31 , the second control loop 32 , the third control loop 33 and the fourth control loop 34 are set by the third relief valve 352 , and the pressure setting value of the third relief valve 352 is lower than the setting values ​​of the first relief valve 314 and the second relief valve 334 .

[0040] In the present invention, when the vehicle is starting, accelerating or moving at a constant speed, the first solenoid valve 313 and the second solenoid valve 333 are in a powered state, and the control valve group is not connected; when the vehicle is braking or going downhill, the first solenoid valve / the second solenoid valve is de-energized according to the running direction, and the corresponding control circuit is connected, and the control pressure oil enters the corresponding running hydraulic pump variable control mechanism to intervene in its displacement change, thereby controlling the engine speed of the first running hydraulic pump / the second running hydraulic pump.

[0041] In this embodiment, the control valve group 3 adopts an integrated design, and each functional valve adopts a threaded cartridge valve, which has a compact structure. Of course, it can also be implemented in an integrated manner of plate-type or sheet-type stacking; each functional valve can also be implemented in a split structure.

[0042] It should be noted that the running hydraulic pump speed stabilization control system provided by the present invention, taking a dual-pump dual-motor system as an example, can be used for a single-pump single-motor system and a multi-pump multi-motor system by increasing or decreasing the number of control loops.

[0043] It should be noted that the running hydraulic pump speed stabilization control system provided by the present invention can be applied to other fields besides railway engineering machinery.

[0044] Compared with the prior art, the travel hydraulic pump speed stabilization control system provided by the present invention has the following beneficial effects:

[0045] 1. The travel hydraulic pump speed stabilization control system provided by the present invention stabilizes the hydraulic pump speed by intervening in the displacement of the hydraulic pump through the control valve group when the vehicle is braking or going downhill, thereby achieving the purpose of stabilizing the engine speed. The engine speed deviation of the travel hydraulic pump can be controlled within ±50rpm.

[0046] 2. The travel hydraulic pump speed stabilization control system provided by the present invention has an integrated control valve group, and each functional valve adopts a threaded cartridge valve, which has a compact structure.

[0047] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations made to these embodiments without departing from the principles and spirit of the present invention are still within the scope of protection of the present invention.

Claims

1. A travel hydraulic pump speed stabilization control system, characterized in that: It includes a first running hydraulic pump oil circuit block, a second running hydraulic pump oil circuit block, and a control valve group; the first running hydraulic pump oil circuit block and the second running hydraulic pump oil circuit block respectively include two working oil ports and a running hydraulic pump variable control mechanism, and the input end of the control valve group is connected to the working oil port of the first running hydraulic pump oil circuit block / the second running hydraulic pump oil circuit block, and the output end of the control valve group is connected to the running hydraulic pump variable control mechanism; The control valve group includes a first control circuit and a second control circuit respectively connected to one of the working oil ports of the first running hydraulic pump oil circuit block and the second running hydraulic pump oil circuit block, a third control circuit and a fourth control circuit respectively connected to the other working oil ports of the first running hydraulic pump and the second running hydraulic pump oil circuit block, and a control pressure setting circuit; the output ends of the first control circuit, the second control circuit, the third control circuit and the fourth control circuit are respectively connected to the corresponding running hydraulic pump variable control mechanism; The first control circuit includes a first one-way valve, a first throttle valve, a first solenoid valve, a first overflow valve, and a second one-way valve connected in sequence from the input end to the output end; The second control loop is formed by sequentially connecting a third one-way valve, a first throttle valve, a first solenoid valve, a first overflow valve and a fourth one-way valve; The third control circuit includes a fifth one-way valve, a second throttle valve, a second solenoid valve, a second overflow valve, and a sixth one-way valve connected in sequence from the input end to the output end; The fourth control loop is formed by sequentially connecting the seventh one-way valve, the second throttle valve, the second solenoid valve, the second overflow valve and the eighth one-way valve; The control pressure setting circuit includes a shuttle valve and a third relief valve; the shuttle valve includes three oil ports, one of which is connected between the first relief valve and the second check valve of the first control circuit, and is also connected between the first relief valve and the fourth check valve of the second control circuit, another oil port is connected between the second relief valve and the sixth check valve of the third control circuit, and is also connected between the second relief valve and the eighth check valve of the fourth control circuit, and the third oil port is connected to the third relief valve; When the vehicle is starting, accelerating or moving at a constant speed, the first solenoid valve and the second solenoid valve are energized and the control valve group is not connected; when the vehicle is braking or going downhill, the first solenoid valve / the second solenoid valve is de-energized according to the running direction, and the corresponding control circuit is connected, and the control pressure oil enters the corresponding running hydraulic pump variable control mechanism to intervene in its displacement change, thereby controlling the engine speed of the first running hydraulic pump / the second running hydraulic pump; the control pressure of the first control circuit, the second control circuit, the third control circuit, and the fourth control circuit is set by the third relief valve, and the pressure setting value of the third relief valve is lower than the setting value of the first relief valve and the second relief valve; the control valve group is an integrated design; each functional valve adopts a threaded cartridge valve.

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