阅读说明：本技术 一种抗时变大偏载的分流马达变速同步系统及工作方法 (Shunt motor speed change synchronization system capable of resisting time-varying large unbalance load and working method ) 是由 丁海港 刘永状 赵继云 赵延斌 曹超 陈世其 赵亮 于 2020-07-03 设计创作，主要内容包括：本发明公开了一种抗时变大偏载的分流马达变速同步系统,属于液压同步控制领域。包括负载敏感变量泵、比例方向阀、分流马达,压力补偿阀、换向阀、执行元件,并依次连接,而分流马达具有多联,每一联的出油口连接一个执行器支路,实现多个液压执行器的变速同步驱动,还公开了变速同步系统的工作方法,其经过变速、分流、压力补偿、负载敏感控制四个环节,可实现大偏载或时变负载工况下的高精度、高效率变速同步驱动控制,且结构简单、可靠性高,尤其适用于恶劣环境下的同步驱动,可彻底消除偏载对分流精度的影响,并可抵抗时变负载的干扰。(The invention discloses a shunt motor speed change synchronous system capable of resisting time-varying large unbalance loading, and belongs to the field of hydraulic synchronous control. The variable speed synchronous system comprises a load sensitive variable pump, a proportional directional valve, a shunt motor, a pressure compensation valve, a reversing valve and an execution element which are sequentially connected, wherein the shunt motor is provided with multiple joints, an oil outlet of each joint is connected with an actuator branch to realize variable speed synchronous drive of a plurality of hydraulic actuators, and the variable speed synchronous system also discloses a working method of the variable speed synchronous system.)

1. The utility model provides a reposition of redundant personnel motor variable speed synchronous system of anti time-varying big unbalance loading which characterized in that: the variable-speed synchronous driving device comprises a load sensitive variable pump (1), a proportional direction valve (2) and a plurality of shunt motors (3) which are connected in sequence, wherein the proportional direction valve (2) is of a three-way structure, an oil inlet of the proportional direction valve is connected with an oil outlet of the load sensitive pump (1) through a pipeline, an oil return port of the proportional direction valve is connected with an oil tank, and an oil outlet pipeline of each shunt motor (3) is connected with a hydraulic actuator (7) through an actuator branch circuit, so that variable-speed synchronous driving of the plurality of hydraulic actuators is realized;

the actuator branch comprises an overflow oil supplementing loop (4) with one end connected with an oil outlet of the shunt motor (3), and the overflow oil supplementing loop (4) is connected with a reversing valve (6) through a pressure compensation valve (5); the overflow oil supplementing loop (4) comprises an overflow valve (4.1) and a one-way valve (4.2) which are respectively arranged on a pipeline, the overflow valve and the one-way valve are connected in parallel at an oil outlet of the shunt motor (3), an oil return port of the overflow valve is communicated with an oil tank, a terminal error can be eliminated by the overflow valve (4.1), the one-way valve (4.2) is used for supplementing oil, an inlet of the pressure compensation valve (5) is connected with an outlet of the shunt motor (3), an outlet pipeline of the pressure compensation valve (5) is connected with an oil inlet of the reversing valve (6), and Ls ports of all the pressure compensation valves (5) are communicated and connected into the load sensitive variable pump (.

2. The shunt motor variable speed synchronizing system of claim 1 wherein: the shunt motor (3) is a plunger type shunt motor or a gear type shunt motor.

3. The shunt motor variable speed synchronizing system of claim 1 wherein: the reversing valve (6) is a two-position four-way electromagnetic reversing valve, and an outlet of the reversing valve (6) is connected with two cavities of the hydraulic actuator (7) and used for changing the running direction of the actuator (7).

4. A working method of a shunt motor variable speed synchronous system capable of resisting time-varying large unbalance loading is characterized by comprising the following steps:

1) maintaining the pressure drop of the proportional direction valve to be basically constant, changing the opening size of the proportional direction valve (2), and adjusting the total flow Q of oil entering the shunt motor (3) so as to control the synchronous speed of each hydraulic actuator (7);

2) the total flow Q of oil liquid for driving each hydraulic actuator (7) is pumped into a plurality of proportional directional valves (2) by a load sensitive variable pump (1) and is divided into a plurality of branch flows by a shunt motor (3);

3) the pressure compensation valve (5) is used for compensating the load deviation of the hydraulic actuator (7) to change the unbalance loading into uniform loading, so that the influence of the unbalance loading on the oil flow averagely distributed to each actuator branch of the shunt motor (3) is thoroughly eliminated, and the large unbalance loading resistance of the shunt motor (3) is further improved;

4) the pressure compensation valve (5) collects the highest load pressure of the whole shunt motor speed change synchronous system and feeds the highest load pressure back to the load sensitive variable pump (1), and the flow and the pressure of oil output by the load sensitive variable pump (1) are consistent with the load requirement through the load sensitive control of the highest load pressure, so that the efficiency of each control hydraulic actuator (7) is improved, and the capacity of resisting load change is improved.

5. The synchronous working method according to claim 4, characterized in that:

using the formula:

6. The method of claim 4, wherein the formula Q ∑ Q is used_iCalculating the total flow Q of oil passing through the proportional direction valve (2) by the sum of the oil flow in each actuator branch, wherein Q_iThe flow is divided into a plurality of actuator branches i equally by a shunt motor (3), wherein i is 1-n, n is more than or equal to 2, and n is the number of the actuator branches.

7. The method of operation of claim 4, wherein: let the load pressure of any actuator branch i be P_LiLoad pressure P_LiThe oil outlets of the pressure compensation valves (5) acting on the corresponding actuator branch circuits i are communicated with the ports Ls of all the pressure compensation valves (5), and the highest load pressure P of the actuator branch circuits i is taken_m＝max(P_Li) The highest load pressure is fed back to a spring cavity of a pressure compensating valve (5) in the actuator branch circuit i and generates a spring force P together with the spring cavity_kiAct on the valve core of the pressure compensation valve (5) together, and the pressure compensation valve (5) is in a stable state;

using the formula: p_ci＝P_m+P_kiCalculating the pressure P at the inlet of the pressure compensation valve (5) when it is in a steady state_ciSince the same pressure compensation valve (5) is used in each actuator branch, the spring force P of the spring chamber thereof_kiEqual, and therefore the pressure P of the inlet_ciAre also equal; thus, although the load pressure P of each branch_LiDifferent, but separate, motor (3) each associated with an outlet pressure P_ciBut are substantially equal, the total flow Q of oil is equally distributed by the shunt motor (3) so that the flow of each actuator branch is equal, i.e. Q_iAnd (2) compensating the load deviation of each branch hydraulic actuator (7) by adopting a pressure compensation valve (5) to ensure that the unbalance loading becomes uniform loading, thoroughly eliminating the influence of the unbalance loading on the shunting precision, further improving the large unbalance loading resistance of the shunting motor (3) and realizing the unbalance loading compensation of each actuator branch.

8. The method of operation of claim 4, wherein: the pressure compensation valve (5) collects the highest load pressure P of the whole shunt motor variable speed synchronous system_mAnd the flow rate of the load-sensitive variable pump (1) is the total flow rate Q of the oil liquid under the load-sensitive control of the load-sensitive variable pump (1), and in order to avoid overflow loss, the outlet pressure of the load-sensitive variable pump (1) is P_s＝P_m+P_d，P_dThe pressure margin of the load sensitive pump (1) is 2-3 MPa; it can be seen that when the outlet flow and the pressure of the load-sensitive variable pump (1) are suitable for the load, the flow and the pressure can be improvedThe efficiency and ability to resist load variations of the synchronous drive system;

the total pressure drop of the proportional direction valve (2) and the shunt motor (3) is P_s-P_ci＝P_d-P_ki＝ΔP_v+ΔP_miConstant value, where Δ P_miThe pressure drop of the branch of the i-connection actuator by the shunt motor is maintained to be constant, delta P_vIs the pressure drop of the proportional directional valve, the pressure drop deltaP by maintaining the proportional directional valve when the load changes_vThe speed regulating characteristic of the synchronous system is not influenced by load change.

Technical Field

The invention relates to a speed change synchronization system and a working method of a shunt motor, in particular to a speed change synchronization system and a working method of a shunt motor, which are resistant to time-varying large unbalance loading, and belong to the field of hydraulic synchronization control.

Background

Heavy equipment is heavily loaded and requires multiple hydraulic actuators to be driven in unison. The shunt motor is formed by connecting a plurality of hydraulic motors with higher processing precision and the same size through rigid shafts, and can realize the synchronous action of up to 12 hydraulic actuators. Compared with a shunt valve, the shunt error of the current shunt motor is smaller, and is 1% -3%. However, the anti-unbalance loading capability of the shunt motor is not strong, and when the load deviation between the branches is increased, the shunt error of the shunt motor is further increased. For example, the shunt error for RV-series shunt motors for VIVOIL, italy, is around 1.5% at even load and 8% at 10MPa offset load. Therefore, to ensure the accuracy of the shunt motor, it is generally recommended that the unbalance loading thereof does not exceed 7 MPa. Therefore, the current shunt motor is difficult to obtain high-precision synchronous control under the working condition of time-varying large unbalance loading. In addition, the synchronous speed of the current shunt motor synchronous system is not adjustable, so that the impact of the starting brake pressure is large, the system is difficult to be used for fine operation, the system generally adopts a constant delivery pump for supplying oil, the overflow loss is inevitable, the system generates heat, and the service life of the system is endangered.

Disclosure of Invention

Aiming at the defects of the technology, the shunting motor speed change synchronous system and the working method can realize high-precision and high-efficiency shunting motor speed change synchronous drive under the working condition of large unbalance loading or time-varying load, have simple structure and resist the time-varying large unbalance loading by high-precision equivalent shunting under the large unbalance loading of oil.

In order to achieve the purpose, the shunt motor speed change synchronous system capable of resisting time-varying large unbalance loading comprises a load sensitive variable pump, a proportional direction valve and a plurality of shunt motors which are arranged in a multi-connected mode, wherein the load sensitive variable pump, the proportional direction valve and the shunt motors are sequentially connected;

the actuator branch comprises an overflow oil supplementing loop, one end of the overflow oil supplementing loop is connected with an oil outlet of the shunt motor, and the overflow oil supplementing loop is connected with a reversing valve through a pressure compensation valve; the overflow oil-supplementing loop comprises an overflow valve and a one-way valve which are respectively arranged on a pipeline, the overflow valve and the one-way valve are connected in parallel with an oil outlet of the shunt motor, an oil return port of the overflow valve is communicated with an oil tank, the overflow valve can eliminate a terminal error, the one-way valve is used for supplementing oil, an inlet of the pressure compensation valve is connected with an outlet of the shunt motor, an outlet pipeline of the pressure compensation valve is connected with an oil inlet of the reversing valve, and Ls ports of all the pressure compensation valves are communicated and connected into the load sensitive.

The shunt motor is a plunger type shunt motor or a gear type shunt motor.

The reversing valve is a two-position four-way electromagnetic reversing valve, and an outlet of the reversing valve is connected with two cavities of the hydraulic actuator and used for changing the operation direction of the actuator;

a working method of a shunt motor variable speed synchronous system capable of resisting time-varying large unbalance loading comprises the following steps:

1) maintaining the pressure drop of the proportional direction valve to be basically constant, changing the size of an opening of the proportional direction valve, and adjusting the total flow of oil entering a shunt motor so as to control the synchronous speed of each hydraulic actuator;

2) the total flow of oil liquid for driving each hydraulic actuator is pumped into a plurality of proportional directional valves by a load sensitive variable pump and divided into a plurality of branch flows by a shunt motor;

3) the pressure compensation valve is used for compensating the load deviation of the hydraulic actuator, so that the unbalance loading becomes uniform, the influence of the unbalance loading on the oil flow averagely distributed to each actuator branch of the shunt motor is thoroughly eliminated, and the large unbalance loading resistance of the shunt motor is further improved;

4) the pressure compensation valve collects the highest load pressure of the whole shunt motor speed change synchronous system and feeds the highest load pressure back to the load sensitive variable pump, and the flow and the pressure of oil output by the load sensitive variable pump are consistent with the load requirement through the load sensitive control of the highest load pressure, so that the efficiency of each control hydraulic actuator is improved, and the capacity of resisting load change is improved.

Using the formula:

calculating the total flow Q of oil passing through the proportional directional valve, where K is the valve coefficient and x_vIs the opening degree of the proportional directional valve, P_sIs the inlet pressure of the proportional directional valve, and is also the outlet pressure of the load-sensitive variable pump, P_vIs the outlet pressure of the proportional directional valve, also the inlet pressure of the shunt motor, Δ P_vIs the pressure drop of the proportional directional valve; by varying the opening x of the proportional directional valve_vThe total flow Q of oil liquid of the whole shunt motor speed-changing synchronous system is regulated, and the operation speed of an actuator corresponding to the actuator branch is finally controlled through the oil liquid flow input by the reversing valve on each actuator branch.

Using the formula Q- ∑ Q_iCalculating the total flow Q of oil passing through the proportional direction valve and the sum of the oil flow in each actuator branch, wherein Q_iThe flow rate of a plurality of actuator branches i is uniformly divided by a shunt motor, i is equal to 1-n, n is more than or equal to 2, and n is the number of the actuator branches.

Let the load pressure of any actuator branch i be P_LiLoad pressure P_LiThe oil outlets of the pressure compensation valves acting on the corresponding actuator branch i are communicated with the ports Ls of all the pressure compensation valves, and the highest load pressure P of the actuator branch i is taken_m＝max(P_Li) The highest load pressure is fed back to the spring cavity of the pressure compensating valve in the actuator branch i and is combined with the spring force P generated by the spring cavity_kiActing on the valve cores of the pressure compensation valve together, wherein the pressure compensation valve is in a stable state;

using the formula: p_ci＝P_m+P_kiCalculating the pressure P at the inlet of the pressure compensating valve when it is in steady state_ciSince the same pressure compensation valve is used in each actuator branch, the spring force P of its spring chamber_kiEqual, and therefore the pressure P of the inlet_ciAre also equal; thus, although the load pressure P of each branch_LiDifferent, but split-flow motor respective outlet pressure P_ciBut are substantially equal, the total flow of oil Q is equally distributed by the split motors so that the flow in each actuator branch is equal, i.e. Q_iAnd the pressure compensation valve is adopted to compensate the load deviation of the hydraulic actuators of each branch, so that the unbalance loads are changed into uniform loads, the influence of the unbalance loads on the shunting precision is thoroughly eliminated, the large unbalance load resistance of the shunting motor is further improved, and the unbalance load compensation of each actuator branch is realized.

The pressure compensation valve collects the highest load pressure P of the whole shunt motor speed change synchronous system_mAnd the pressure is fed back to the load sensitive variable pump through a pipeline, the flow of the load sensitive variable pump is the total flow Q of the oil liquid under the load sensitive control of the load sensitive variable pump, and the outlet pressure of the load sensitive variable pump is P to avoid overflow loss_s＝P_m+P_d，P_dThe pressure margin of the load sensitive pump is 2-3 MPa; therefore, when the outlet flow and the pressure of the load sensitive variable pump are suitable for the load, the efficiency of the synchronous driving system and the capacity of resisting load change can be improved;

the total pressure drop of the proportional direction valve and the shunt motor is P_s-P_ci＝P_d-P_ki＝ΔP_v+ΔP_miConstant value, where Δ P_miIs the pressure drop of the shunt motor i-connection, and maintains a constant value, delta P_vIs the pressure drop of the proportional directional valve, the pressure drop deltaP by maintaining the proportional directional valve when the load changes_vThe speed regulating characteristic of the synchronous system is not influenced by load change.

Has the advantages that: the invention can compensate the load deviation among the branches by utilizing the pressure compensation principle, so that the outlet pressure of each link of the shunt motor is equal, the influence of the unbalance load on the shunt precision of each actuator branch output by the shunt motor is thoroughly eliminated, and high-precision equivalent shunt under large unbalance load is realized; the flow of the system is regulated through the proportional valve, and the synchronous control of speed change can be realized; through the load sensitive control, the efficiency of the synchronous system can be improved, and the interference of time-varying loads can be resisted. The invention organically combines the structure and the principle of synchronous driving and load sensitive control of the shunt motor, can realize high-precision and high-efficiency variable speed synchronous driving control under the working condition of large unbalance loading or time-varying load, has simple structure and high reliability, is especially suitable for synchronous driving under severe environment, and can replace part of closed-loop synchronous control under the conventional environment.

Drawings

Fig. 1 is a schematic structural diagram of a shunt motor variable speed synchronous system for resisting time-varying large unbalance loading according to the invention.

Fig. 2 is a schematic structural diagram of an actuator branch in the shunt motor variable speed synchronous system for resisting time-varying large unbalance loading according to the invention.

In the figure: 1-load sensitive variable pump, 2-proportional direction valve, 3-shunt motor, 4-overflow oil supplementing loop, 4.1-overflow valve, 4.2-one-way valve, 5-pressure compensation valve, 6-reversing valve and 7-hydraulic actuator

Detailed Description

The invention is further explained below with reference to the drawings.

As shown in fig. 1, the shunt motor speed change synchronous system of the invention for resisting time-varying large unbalance loading comprises a load sensitive variable pump 1, a proportional directional valve 2 and a plurality of shunt motors 3 which are arranged in a multiple connection way, wherein the load sensitive variable pump 1, the proportional directional valve 2 and the shunt motors are connected in sequence, the proportional directional valve 2 is of a three-way structure, an oil inlet of the proportional directional valve is connected with an oil outlet of the load sensitive pump 1 through a pipeline, an oil return port of the proportional directional valve is connected with an oil tank, and an oil outlet pipeline of each shunt motor 3 is connected with a hydraulic actuator 7 through an actuator branch, so that the speed;

the proportional directional valve 2 is preferably a two-position three-way type, a port P is connected with an oil outlet of the load sensitive pump 1, a port T is connected with an oil tank, a port A is connected with an oil inlet of the shunt motor 3, the shunt motor 3 is a plunger type or gear type shunt motor, and an outlet of each branch is connected with an actuator branch.

As shown in fig. 2, the actuator branch comprises an overflow oil-supplementing loop 4 with one end connected with an oil outlet of the shunt motor 3, and the overflow oil-supplementing loop 4 is connected with a reversing valve 6 through a pressure compensation valve 5; the overflow oil supplementing loop 4 comprises an overflow valve 4.1 and a one-way valve 4.2 which are respectively arranged on a pipeline, the overflow valve 4.1 and the one-way valve 4.2 are connected in parallel at an oil outlet of the shunt motor 3, an oil return port of the overflow valve is communicated with an oil tank, the overflow valve 4.1 can eliminate a terminal error, the one-way valve 4.2 is used for supplementing oil, an inlet of the pressure compensation valve 5 is connected with an outlet of the shunt motor 3, an outlet of the pressure compensation valve 5 is connected with a P port of the reversing valve 6, LS ports of all the pressure compensation valves 5 are communicated and connected into the load sensitive variable pump 1, an outlet pipeline of the pressure compensation valve 5 is connected with an oil inlet of the reversing valve 6, and LS. The reversing valve 6 is a two-position four-way electromagnetic reversing valve, and the outlet of the reversing valve is connected with two cavities of the hydraulic actuator 7 and used for changing the running direction of the actuator 7; the hydraulic actuator 7 is a hydraulic cylinder or a hydraulic motor.

A working method of a shunt motor speed change synchronous system for resisting time-varying large unbalance loading comprises four links of speed change, shunt, unbalance loading compensation and load sensitive control so as to realize high-precision and high-efficiency speed change synchronous drive under the working condition of large unbalance loading or time-varying loading,

the method comprises the following specific steps:

1) speed change: maintaining the pressure drop of the proportional direction valve to be basically constant, changing the opening size of the proportional direction valve 2, and adjusting the total flow Q of oil entering the shunt motor 3 so as to control the synchronous speed of each hydraulic actuator 7;

using the formula:calculating the total flow Q of the oil passing through the proportional directional valve 2, where K is the valve coefficient and x_vIs the opening degree of the proportional directional valve, P_sIs the inlet pressure of the proportional directional valve, and is also the outlet pressure, P, of the load-sensitive variable displacement pump 1_vIs the outlet pressure of the proportional directional valve, which is also the inlet pressure of the shunt motor 3, Δ P_vIs the pressure drop of the proportional directional valve; by varying the opening x of the proportional directional valve 2_vTo regulate the total oil flow Q of the whole shunt motor speed-changing synchronous system and pass through each actuatorThe flow of oil input by a reversing valve 6 on the branch of the actuator finally controls the running speed of an actuator 7 corresponding to the branch of the actuator;

2) shunting: the total flow Q of oil liquid for driving each hydraulic actuator 7 is pumped into a plurality of proportional directional valves 2 by a load sensitive variable pump 1 and divided into a plurality of branch flows by a shunt motor 3;

using the formula Q- ∑ Q_iCalculating the total flow Q of oil passing through the proportional direction valve 2 from the sum of the oil flow in each actuator branch, wherein Q_iThe flow is divided into a plurality of actuator branches i equally by a shunt motor 3, wherein i is 1-n, n is more than or equal to 2, and n is the number of the actuator branches.

3) Offset load compensation: the pressure compensating valve 5 is used for compensating the load deviation of the hydraulic actuator 7, so that the unbalance loading becomes uniform, the influence of the unbalance loading on the oil flow averagely distributed to each actuator branch by the shunt motor 3 is thoroughly eliminated, and the large unbalance loading resistance of the shunt motor 3 is further improved;

let the load pressure of any actuator branch i be P_LiLoad pressure P_LiThe oil outlets of the pressure compensation valves 5 acting on the corresponding actuator branch circuits i are communicated with the ports Ls of all the pressure compensation valves 5, and the highest load pressure P of the actuator branch circuits i is taken_m＝max(P_Li) The highest load pressure is fed back to the spring chamber of the pressure compensation valve 5 in the actuator branch i and is associated with the spring force P generated by the spring chamber_kiAct on the valve core of the pressure compensating valve 5 together, and the pressure compensating valve 5 is in a stable state;

using the formula: p_ci＝P_m+P_kiCalculating the pressure P at the inlet of the pressure compensation valve 5 when it is in the steady state_ciSince the same pressure compensation valve 5 is used in each actuator branch, the spring force P of its spring chamber_kiEqual, and therefore the pressure P of the inlet_ciAre also equal; thus, although the load pressure P of each branch_LiDifferent, but separate, outlet pressure P of each of the motors 3_ciBut substantially equal, the total flow Q of oil is equally distributed by the shunt motor 3, so that the flow of each actuator branch is equal, i.e. Q_iThe pressure compensation valve 5 is adopted to compensate the deviation of the load of each branch hydraulic actuator 7, so that the deviation is compensatedThe unbalance loading becomes the uniform loading, the influence of the unbalance loading on the shunt precision is thoroughly eliminated, the large unbalance loading resistance of the shunt motor 3 is further improved, and the unbalance loading compensation of each actuator branch is realized.

4) Load-sensitive control: the pressure compensation valve 5 collects the highest load pressure of the whole shunt motor speed change synchronous system and feeds the highest load pressure back to the load sensitive variable pump 1, and the flow and the pressure of oil output by the load sensitive variable pump 1 are consistent with the load requirement through the load sensitive control of the highest load pressure, so that the efficiency of each control hydraulic actuator 7 and the capacity of resisting load change are improved;

the pressure compensation valve 5 collects the highest load pressure P of the whole shunting motor variable speed synchronous system_mAnd the pressure is fed back to the load-sensitive variable pump 1 through a pipeline, the flow of the load-sensitive variable pump 1 is the total flow Q of the oil liquid under the load-sensitive control of the load-sensitive variable pump 1, and in order to avoid overflow loss, the outlet pressure of the load-sensitive variable pump 1 is P_s＝P_m+P_d，P_dThe pressure margin of the load sensitive pump 1 is 2-3 MPa; it can be seen that when the outlet flow and pressure of the load-sensitive variable pump 1 are suitable for the load, the efficiency of the synchronous driving system and the capacity of resisting load change can be improved;

the total pressure drop of the proportional directional valve 2 and the shunt motor 3 is P_s-P_ci＝P_d-P_ki＝ΔP_v+ΔP_miThe value is equal to the constant value,

in the formula,. DELTA.P_miThe pressure drop of the branch circuit of the i-connection actuator by the shunt motor 3 is maintained to be constant, delta P_vIs the pressure drop of the proportional directional valve, the pressure drop deltaP by maintaining the proportional directional valve when the load changes_vThe speed regulating characteristic of the synchronous system is not influenced by load change.