阅读说明：本技术 一种负载敏感分流阀、变速同步驱动系统及工作方法 (Load-sensitive flow divider valve, variable-speed synchronous driving system and working method ) 是由 丁海港 刘永状 赵继云 赵延斌 赵亮 于 2020-05-22 设计创作，主要内容包括：本发明公开了一种负载敏感分流阀、变速同步驱动系统及工作方法,适用于液压同步控制领域中使用。其包括变速分流单元、流量补偿单元、压力补偿单元,这三个功能单元依次连接,变速分流单元的入口管路连接负载敏感变量泵,压力补偿单元的出口管路连接液压执行器,该分流阀具有分流、调速、负载敏感的功能。还公开了包含该分流阀的变速同步驱动系统与工作方法,可实现大偏载或时变负载工况下的高精度、宽范围、高效率变速同步驱动控制,且结构简单、成本低、可靠性高,尤其适用于恶劣环境下的同步驱动,并可取代常规环境下一部分闭环同步控制。(The invention discloses a load-sensitive flow divider valve, a variable-speed synchronous driving system and a working method, which are suitable for being used in the field of hydraulic synchronous control. The variable-speed flow divider comprises a variable-speed flow dividing unit, a flow compensation unit and a pressure compensation unit which are sequentially connected, wherein an inlet pipeline of the variable-speed flow dividing unit is connected with a load sensitive variable pump, an outlet pipeline of the pressure compensation unit is connected with a hydraulic actuator, and the flow dividing valve has the functions of flow dividing, speed regulating and load sensing. The variable-speed synchronous driving system comprises the flow divider, a speed-changing synchronous driving control unit and a control unit, wherein the speed-changing synchronous driving control unit is used for controlling the speed-changing synchronous driving control unit to control the speed-.)

1. A load sensitive diverter valve characterized by: the variable-speed flow distribution device comprises a variable-speed flow distribution unit (1), a flow compensation unit (2) and a pressure compensation unit (3), wherein the three units are sequentially connected through a pipeline, an inlet of the variable-speed flow distribution unit (1) is a port P, and an outlet of the pressure compensation unit (3) is divided into a port A and a port B;

the variable speed shunting unit (1) is of a three-way valve structure and comprises a P port serving as an inlet, a left controllable throttling port (1.2) and a right controllable throttling port (1.3) serving as an outlet, and pump source oil is divided into a left branch and a right branch by the left controllable throttling port (1.2) and the right controllable throttling port (1.3); the opening degree of the left controllable throttling port (1.2) and the opening degree of the right controllable throttling port (1.3) are always kept the same, and a valve core of the three-way valve moves under the pushing of the driving device (1.1) to change the opening degrees of the two throttling ports, so that the total flow of the split flow is adjusted, and the hydraulic synchronization speed of the inlet is further adjusted;

the flow compensation unit (2) comprises valve sleeves (2.1) which are arranged in bilateral symmetry, a compensation valve core (2.3) is arranged in each valve sleeve (2.1), each compensation valve core (2.3) is provided with a left-middle-right three-section plunger, a reset spring (2.2) is arranged between the top end of each left-middle-section plunger and the bottom of each valve sleeve (2.1), each reset spring (2.2) acts on two ends of each compensation valve core (2.3) to enable each compensation valve core (2.3) to be centered in each valve sleeve (2.1), a left throttling port (2.4) is formed between the middle-section plunger of each compensation valve core (2.3) and the left side of each valve sleeve, a right throttling port (2.5) is formed between the middle-section plunger of each compensation valve core and the right side of each valve sleeve, and;

the pressure compensation unit (3) comprises a left pressure compensation valve (3.1) and a right pressure compensation valve (3.2) which are arranged side by side, oil inlets of the left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) are respectively connected with outlet pipelines of a left throttling opening (2.4) and a right throttling opening (2.5) in the flow compensation unit (2), oil outlets of the left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) are respectively connected with two driving oil cylinders, the left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) are also connected with a shuttle valve (3.3), the oil outlets of the left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) are respectively connected with the left oil inlet and the right oil inlet of the shuttle valve (3.3), the hydraulic control ports of the left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) are respectively connected with the oil outlet of the shuttle valve (3.3), the oil outlet of the shuttle valve (3.3) is an Ls port, and the highest load pressure of the whole load sensitive flow divider valve is acquired.

2. The load sensitive diverter valve of claim 1, wherein: the left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) are both BLF10 in type, and the shuttle valve (3.3) is VU2P in type.

3. The load sensitive diverter valve of claim 1, wherein: the opening degree change trends of a left throttle orifice (2.4) and a right throttle orifice (2.5) in the flow compensation unit (2) are opposite; the inlet of the left throttling orifice (2.4) and the left spring cavity are connected with the outlet of a left controllable throttling orifice in the variable-speed flow splitting unit (1), oil in the left controllable throttling orifice enters the left pressure compensation valve (3.1) through the left throttling orifice (2.4), the inlet of the right throttling orifice (2.5) and the right spring cavity are connected with the outlet of a right controllable throttling orifice (1.3) in the variable-speed flow splitting unit (1), and oil in the right controllable throttling orifice enters the right pressure compensation valve (3.2) through the right throttling orifice (2.5); the compensating valve core (2.3) keeps balance under the action of spring force and hydraulic pressure to change the opening degrees of the left throttling port (2.4) and the right throttling port (2.5) so as to adjust the hydraulic resistance of a left branch and a right branch which are connected with the compensating valve core, the opening degrees of the left throttling port (2.4) and the right throttling port (2.5) are adjusted by depending on the displacement of the compensating valve core (2.3), one opening degree of the two throttling ports is increased, the other opening degree of the two throttling ports is decreased, and the change trends are opposite.

4. A variable speed synchronous drive system using the load sensitive diverter valve of the preceding claims, wherein: a P port of the variable speed shunting unit (1) is used as an oil inlet and is connected with a load sensitive variable pump (4) through a pipeline, an A port and a B port of the pressure compensation unit (3) are connected with a left driving oil cylinder (6) and a right driving oil cylinder (7), and the A port and the B port are respectively connected with rod cavities of the left driving oil cylinder (6) and the right driving oil cylinder (7) through pipelines; the highest load pressure is fed back to the pressure feedback oil port of the load sensitive variable pump (4) through the load pressure feedback oil port Ls of the pressure compensation unit (3), and the highest load pressure is fed back to the left pressure compensation valve (3.1), the right pressure compensation valve (3.2) and the variable pump (4) through the shuttle valve (3.3), so that load sensitive control is achieved.

5. The variable speed synchronous drive system of claim 4, wherein: the pressure feedback mode of the variable speed synchronous driving system comprises one of hydraulic feedback and electric feedback.

6. The variable speed synchronous drive system of claim 4, wherein: the type of the load-sensitive variable pump (4) is A11 VODRS.

7. A working method using the load-sensitive shunt synchronous drive of the above claims to achieve high-precision equivalent shunt under large-offset or time-varying load conditions, characterized by the process of:

firstly, oil input by a load-sensitive pump (4) through a P port is divided into a left branch and a right branch by a variable speed shunting unit (1) and finally reaches a left controllable throttling port (1.2) and a right controllable throttling port (1.3), and the left branch flow Q is obtained by utilizing the left controllable throttling port (1.2) and the right controllable throttling port (1.3)₁And right branch flow Q₂Changed to left side pressure P₁And right side pressure P₂(ii) a The opening degrees of the left controllable throttling port (1.2) and the right controllable throttling port (1.3) are manually changed, so that the total flow of the load-sensitive flow divider valve (5) is changed, and the synchronous speed of the left driving oil cylinder (6) and the right driving oil cylinder (7) is further adjusted;

left side pressure P after diversion₁And right side pressure P₂The oil acts on two ends of the compensating valve core to push the valve core to move so as to adjust the hydraulic resistance of the two branches, thereby compensating the flow deviation of the two branches and leading the pressure P of the two branches₁＝P₂Flow rate Q₁＝Q₂；

The left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) are used for compensating the load deviation acting on the left driving oil cylinder (6) and the right driving oil cylinder (7), so that the unbalance loading becomes uniform, the influence of unbalance loading on the shunting precision of the variable speed shunting unit (1) is thoroughly eliminated, and the large unbalance loading resistance of the load sensitive shunting valve (5) is further wholly improved;

the shuttle valve (3.3) takes the highest load pressure of the system and feeds the highest load pressure back to the load-sensitive variable pump (4) through a load feedback port, and the displacement of the load-sensitive variable pump is changed through load-sensitive control, so that the load-sensitive variable pump outputs flow and pressure consistent with the load demand, and the efficiency of the synchronous driving system and the capacity of resisting load change are further improved.

8. The working method according to claim 7, characterized by the specific steps of:

a. speed change and flow distribution: firstly, oil liquid input by a load-sensitive pump (4) through a P port is divided into a left branch and a right branch by a variable speed shunting unit (1) and finally reaches a left controllable throttling port (1.2) and a right controllable throttling port (1.3), and the flow Q of the left branch and the flow Q of the right branch are respectively measured by the left controllable throttling port (1.2) and the right controllable throttling port (1.3)₁And Q₂Conversion to pressure P₁And P₂The flow of the left branch and the right branch is as follows:wherein K is the valve coefficient, Q₁And Q₂Flow rates, x, of the left and right branches, respectively_v1And x_v1Respectively, the opening degree of the throttle opening is controlled left and right, and x_v1＝x_v2，P_sIs the pressure at port P, P₁Is the outlet pressure, P, of the left controllable throttle (1.2)₂The outlet pressure of the right controllable throttling orifice (1.3) is used for adjusting the flow Q of the left branch and the right branch by changing the opening degrees of the left controllable throttling orifice (1.2) and the right controllable throttling orifice (1.3)₁And Q₂Further changing the synchronous speed of the left driving oil cylinder (6) and the right driving oil cylinder (7);

b. flow compensation: the pressure after the diversion is P₁And P₂The two paths of oil act on two ends of the compensating valve core (2.3) through pipelines respectively to push the compensating valve core (2.3) to move so as to adjust the hydraulic resistance of the oil in the two branches, and finally the compensating valve core (2.3) is in a balanced state under the combined action of the spring force and the hydraulic pressure of the two return springs (2.2);

the equilibrium state is: (P)₁-P₂) A is equal to K delta x, wherein A is the effective area of the two ends of the left plunger and the right plunger of the compensation valve core (2.3), K is the rigidity of the return spring (2.2), delta x is the displacement of the compensation valve core (2.3), and delta x is the outlet pressure P of the left throttling port (2.4) and the right throttling port (2.5) of the compensation valve core₃And P₄When | P is related to₃-P₄The smaller |, the smaller Δ x, and P₁And P₂The smaller the difference is, the smaller the flow Q of the two branches is₁And Q₂The closer the position is, the higher the shunting precision of the load-sensitive shunting valve (5) is;

c. pressure compensation: setting the load pressure of different oil cylinders as P₅And P₆And P is₅≠P₆The shuttle valve (3.3) takes the maximum value P of the two load pressures of the two branches_m＝max(P₅,P₆) (ii) a If the left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) are in a balanced state, the inlet pressures of the left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) are basically equal, namely P₃≈P₄＝P_m+P_kIn which P is_kThe preset pressure of the left pressure compensation valve (3.1) and the right pressure compensation valve (3.2) is balanced; due to the effect of pressure compensation, | P₃-P₄I is close to zero, Δ x is small, and therefore has P₁≈P₂At this time Q₁≈Q₂Therefore, the unbalance loading becomes uniform through pressure compensation, the influence of unbalance loading on the flow distribution precision is thoroughly eliminated, and the large unbalance loading resistance of the flow distribution valve is further improved;

d. load-sensitive control: the shuttle valve (3.3) takes the highest load pressure P of the system_mAnd the flow rate is fed back to the load-sensitive variable pump (4) through a load feedback port, the load-sensitive variable pump (4) changes the displacement under the action of load-sensitive control, and the output flow rate is the sum Q of the total flow rates of the two branches₁+Q₂The output pressure being adapted to the highest load pressure, i.e. P_s＝P_m+P_dIn which P is_dThe pressure margin is used, the pressure and the flow of the pump source can be consistent with the load requirement through the load sensitive control, so that the capacity of the synchronous system for resisting load change is improved, meanwhile, the overflow loss is reduced, and the efficiency of the synchronous driving system is improved.

Technical Field

The invention relates to a load-sensitive flow divider valve, a variable-speed synchronous driving system and a working method, which are particularly suitable for being used in the field of hydraulic synchronous control.

Background

The hydraulic shunting synchronous drive adopts shunting elements (such as a shunting valve and a shunting motor) as control elements, and realizes the speed synchronization of a plurality of hydraulic actuators by an equivalent shunting principle. Compared with closed-loop synchronous driving by adopting a servo valve or a proportional valve and hydraulic shunt synchronous driving, the hydraulic shunt synchronous driving method is an open-loop synchronous driving mode, does not need to detect and feedback control an actuator, has the advantages of simple structure, low cost, high reliability, capability of adapting to severe environment and the like, is a preferred scheme of high-power synchronous driving, and is widely applied to engineering machinery, aerospace and metallurgical machinery. But the structure and the reposition of redundant personnel principle of current reposition of redundant personnel component have the defect, lead to hydraulic pressure reposition of redundant personnel synchro-driven to be difficult to satisfy the synchronous demand of high accuracy: (1) the shunt element has poor resistance to large unbalance loads. For example, the shunt accuracy of the existing shunt valve and the shunt motor is 3% -5% and 1% -3% respectively, and the greater the unbalance load is, the lower the shunt accuracy is. (2) The flow range of the flow dividing element is narrow, the flow dividing precision is low under low flow, and the flow dividing element does not have a speed regulating function. (3) The existing shunting synchronous driving system generally adopts a constant delivery pump for supplying oil, has large overflow loss and cannot adapt to time-varying load working conditions. In 2019, the inventor discloses an invention patent of an unbalance-load-resistant speed-adjustable synchronous valve, a synchronous control system and a working method (ZL201910812965.3), but the novel synchronous valve comprises a four-layer structure, is complex in structure, large in pressure drop, small in speed-adjusting range and low in load sensitivity. Therefore, the high-precision shunt synchronous driving under the working condition of large unbalance loading or time-varying loading at present is still a great technical problem, and a better solution is not found yet.

Disclosure of Invention

Aiming at the defects of the technology, the load-sensitive flow divider, the variable speed synchronous driving system and the working method thereof are provided, and the variable speed synchronous driving with high precision, high efficiency and wide range can be realized under the working condition of large unbalance load or time-varying load.

To achieve the above object, the load-sensitive diverter valve of the present invention is characterized in that: the variable-speed flow distribution unit is connected with the pressure compensation unit in sequence through a pipeline, wherein an inlet of the variable-speed flow distribution unit is a P port, and an outlet of the pressure compensation unit is divided into an A port and a B port;

the variable speed flow dividing unit is of a three-way valve structure and comprises a P port serving as an inlet and a left controllable throttling port and a right controllable throttling port serving as an outlet, and the pump source oil is divided into a left branch and a right branch by the left controllable throttling port and the right controllable throttling port; the opening sizes of the left controllable throttling port and the right controllable throttling port are always kept the same, and a valve core of the three-way valve moves under the pushing of the driving device to change the opening sizes of the two throttling ports, so that the total flow of the split flow is adjusted, and the hydraulic synchronization speed of the inlet is adjusted;

the flow compensation unit comprises valve sleeves which are arranged in a bilateral symmetry mode, a compensation valve core is arranged in each valve sleeve, each compensation valve core is provided with a left plunger, a middle plunger and a right plunger, a reset spring is arranged between the top end of each left plunger and the bottom of each valve sleeve, the reset springs act on two ends of each compensation valve core to enable the compensation valve core to be centered in each valve sleeve, a left throttling port is formed between the plunger in the middle section of each compensation valve core and the left side of each valve sleeve, a right throttling port is formed between the plunger in the middle section of each compensation valve core and;

the pressure compensation unit comprises a left pressure compensation valve and a right pressure compensation valve which are arranged side by side, oil inlets of the left pressure compensation valve and the right pressure compensation valve are respectively connected with outlet pipelines of a left throttling port and a right throttling port in the flow compensation unit, oil outlets of the left pressure compensation valve and the right pressure compensation valve are respectively connected with two driving oil cylinders, the left pressure compensation valve and the right pressure compensation valve are further connected with shuttle valves, oil outlets of the left pressure compensation valve and the right pressure compensation valve are respectively connected with left and right oil inlets of the shuttle valves, hydraulic control ports of the left pressure compensation valve and the right pressure compensation valve are respectively connected with oil outlets of the shuttle valves, oil outlets of the shuttle valves are Ls ports, and the highest load pressure of the whole load sensitive flow divider is collected.

The left pressure compensation valve and the right pressure compensation valve are both BLF10 in model, and the shuttle valve is VU2P in model.

The opening degree change trends of a left throttle orifice and a right throttle orifice in the flow compensation unit are opposite; the inlet of the left throttling orifice and the left spring cavity are connected with the outlet of a left controllable throttling orifice in the variable speed flow dividing unit, oil in the left controllable throttling orifice enters the left pressure compensation valve through the left throttling orifice, the inlet of the right throttling orifice and the right spring cavity are connected with the outlet of a right controllable throttling orifice in the variable speed flow dividing unit, and the oil in the right controllable throttling orifice enters the right pressure compensation valve through the right throttling orifice; the compensating valve core keeps balance under the action of spring force and hydraulic pressure to change the opening degree of the left throttling port and the right throttling port, so that the liquid resistance of a left branch circuit and a right branch circuit connected with the compensating valve core is adjusted, the opening degrees of the left throttling port and the right throttling port are adjusted by depending on the displacement of the compensating valve core, one of the opening degrees of the two throttling ports is increased, the other one of the opening degrees of the two throttling ports is decreased, and the change trends are opposite.

A port P of the variable speed shunting unit is used as an oil inlet and is connected with a load sensitive variable pump through a pipeline, a port A and a port B of the pressure compensation unit are connected with a left driving oil cylinder and a right driving oil cylinder, and the port A and the port B are respectively connected with rod cavities of the left driving oil cylinder and the right driving oil cylinder through pipelines; and a load pressure feedback oil port Ls port of the pressure compensation unit feeds the highest load pressure back to a pressure feedback oil port of the load sensitive variable pump, and the shuttle valve feeds the highest load pressure back to the left pressure compensation valve, the right pressure compensation valve and the variable pump, so that the load sensitive control is realized.

The pressure feedback mode of the variable speed synchronous driving system comprises one of hydraulic feedback and electric feedback.

The model of the load-sensitive variable pump is A11 VODRS.

A working method of load sensitive shunt synchronous drive is used for realizing high-precision equivalent shunt under the working condition of large unbalance load or time-varying load, and the working method comprises the following steps:

firstly, the oil liquid input by a load-sensitive pump through a P port is divided into a left branch and a right branch by a variable speed shunting unit and finally reaches a left controllable throttling port and a right controllable throttling port, and the left branch flow Q is obtained by utilizing the left controllable throttling port and the right controllable throttling port₁And right branch flow Q₂Changed to left side pressure P₁And right side pressure P₂(ii) a The opening degrees of the left controllable throttling port and the right controllable throttling port are manually changed, so that the total flow of the load sensitive flow divider valve is changed, and the synchronous speed of the left driving oil cylinder and the right driving oil cylinder is further adjusted;

left side pressure P after diversion₁And right side pressure P₂The oil acts on two ends of the compensating valve core to push the valve core to move so as to adjust the hydraulic resistance of the two branches, thereby compensating the flow deviation of the two branches and leading the pressure P of the two branches₁＝P₂Flow rate Q₁＝Q₂；

The left pressure compensation valve and the right pressure compensation valve are used for compensating the load deviation acting on the left driving oil cylinder and the right driving oil cylinder, so that the unbalance loading becomes uniform, the influence of the unbalance loading on the shunting precision of the variable speed shunting unit is thoroughly eliminated, and the large unbalance loading resistance of the load sensitive shunting valve is further improved;

the shuttle valve takes the highest load pressure of the system and feeds the highest load pressure back to the load-sensitive variable pump through the load feedback port, and the displacement of the load-sensitive variable pump is changed through load-sensitive control, so that the load-sensitive variable pump outputs flow and pressure consistent with the load requirement, and the efficiency of the synchronous driving system and the capacity of resisting load change are improved.

The working method comprises the following specific steps:

a. speed change and flow distribution: firstly, the oil liquid input by a load-sensitive pump through a P port is divided into a left branch and a right branch by a variable speed shunting unit and finally reaches a left controllable throttling port and a right controllable throttling port, and the flow Q of the left branch and the right branch is controlled by the left controllable throttling port and the right controllable throttling port₁And Q₂Conversion to pressure P₁And P₂The flow of the left branch and the right branch is as follows:wherein K is the valve coefficient, Q₁And Q₂Flow rates, x, of the left and right branches, respectively_v1And x_v1Respectively, the opening degree of the throttle opening is controlled left and right, and x_v1＝x_v2，P_sIs the pressure at port P, P₁Is to the leftOutlet pressure, P, of a controllable orifice₂The outlet pressure of the right controllable throttling opening is used for adjusting the flow Q of the left branch and the right branch by changing the opening degrees of the left controllable throttling opening and the right controllable throttling opening₁And Q₂Further changing the synchronous speed of the left driving oil cylinder and the right driving oil cylinder;

b. flow compensation: the pressure after the diversion is P₁And P₂The two paths of oil respectively act on two ends of the compensating valve core through pipelines to push the compensating valve core to move so as to adjust the hydraulic resistance of the oil in the two branches, and finally the compensating valve core is in a balanced state under the combined action of the spring force and the hydraulic pressure of the two return springs;

the equilibrium state is: (P)₁-P₂) A is K delta x, wherein A is the effective area of two ends of the left plunger and the right plunger of the compensation valve core, K is the rigidity of the return spring, delta x is the displacement of the compensation valve core, and delta x is the outlet pressure P of the left throttling port and the right throttling port of the compensation valve core₃And P₄When | P is related to₃-P₄The smaller |, the smaller Δ x, and P₁And P₂The smaller the difference is, the smaller the flow Q of the two branches is₁And Q₂The closer the pressure is, the higher the flow dividing precision of the load-sensitive flow dividing valve is;

c. pressure compensation: setting the load pressure of different oil cylinders as P₅And P₆And P is₅≠P₆The shuttle valve takes the maximum value P of two load pressures of two branches_m＝max(P₅,P₆) (ii) a If the left pressure compensating valve and the right pressure compensating valve are in a balanced state, the inlet pressures of the left pressure compensating valve and the right pressure compensating valve are basically equal, namely P₃≈P₄＝P_m+P_kIn which P is_kBalancing the preset pressures of the left pressure compensation valve and the right pressure compensation valve; due to the effect of pressure compensation, | P₃-P₄I is close to zero, Δ x is small, and therefore has P₁≈P₂At this time Q₁≈Q₂Therefore, the unbalance loading becomes uniform through pressure compensation, the influence of unbalance loading on the flow distribution precision is thoroughly eliminated, and the large unbalance loading resistance of the flow distribution valve is further improved;

d. load-sensitive control: maximum load pressure P of shuttle valve system_mAnd the flow rate is fed back to the load-sensitive variable pump through a load feedback port, the load-sensitive variable pump changes the displacement under the action of load-sensitive control, and the output flow rate is the sum Q of the total flow rates of the two branches₁+Q₂The output pressure being adapted to the highest load pressure, i.e. P_s＝P_m+P_dIn which P is_dThe pressure margin is used, the pressure and the flow of the pump source can be consistent with the load requirement through the load sensitive control, so that the capacity of the synchronous system for resisting load change is improved, meanwhile, the overflow loss is reduced, and the efficiency of the synchronous driving system is improved.

Has the advantages that:

the invention utilizes the variable speed shunting principle to enable the shunting valve to have the speed regulating function and the shunting function, thereby realizing variable speed synchronous driving; by utilizing the flow compensation and pressure compensation principles, the unbalance loading is homogenized, the influence of the unbalance loading size on the shunting precision can be thoroughly eliminated, and high-precision equivalent shunting under large unbalance loading is realized; the flow divider valve has a load-sensitive function, and is used in combination with a load-sensitive variable pump, so that the efficiency of the system can be improved, and the interference of a time-varying load can be resisted. The structure and the principle of shunting synchronous drive and load sensitive control are organically combined, so that high-precision, wide-range and high-efficiency variable speed synchronous drive control under the working condition of large unbalance load or time-varying load is realized, the structure is simple, the cost is low, the reliability is high, the synchronous drive device is particularly suitable for synchronous drive under severe environment, and part of closed-loop synchronous control under the conventional environment can be replaced.

Drawings

FIG. 1 is a schematic diagram of the construction of the load sensitive diverter valve of the present invention;

fig. 2 is a schematic diagram of a variable speed synchronous drive system employing the load sensitive diverter valve of the present invention.

In the figure: 1-variable speed diversion unit, 1.1-driving device, 1.2-left controllable throttling orifice, 1.3-right controllable throttling orifice, 2-flow compensation unit, 2.1-valve sleeve, 2.2-reset spring, 2.3-compensation valve core, 2.4-left throttling orifice, 2.5-right throttling orifice, 3-pressure compensation unit, 3.1-left pressure compensation valve, 3.2-right pressure compensation valve, 3.3-shuttle valve, 4-load sensitive variable displacement pump, 5-load sensitive diversion valve, 6-left driving oil cylinder and 7-right driving oil cylinder.

Detailed Description

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

As shown in fig. 1 and 2, the load-sensitive shunt valve 5 of the present invention comprises a variable speed shunt unit 1, a flow compensation unit 2, and a pressure compensation unit 3, which are sequentially connected through a pipeline, wherein an inlet of the variable speed shunt unit 1 is a port P, and an outlet of the pressure compensation unit 3 is divided into a port a and a port B;

the variable speed shunting unit 1 is of a three-way valve structure and comprises a P port serving as an inlet, a left controllable throttling port 1.2 and a right controllable throttling port 1.3 serving as outlets, and pump source oil is divided into a left branch and a right branch by the left controllable throttling port 1.2 and the right controllable throttling port 1.3; the opening degree of the left controllable throttling port 1.2 and the opening degree of the right controllable throttling port 1.3 are always kept the same, and a valve core of the three-way valve moves under the pushing of the driving device 1.1 to change the opening degrees of the two throttling ports, so that the total flow of the split flow is adjusted, and the hydraulic synchronous speed of the inlet is further adjusted;

the flow compensation unit 2 comprises valve sleeves 2.1 which are arranged in bilateral symmetry, a compensation valve core 2.3 is arranged in each valve sleeve 2.1, each compensation valve core 2.3 is provided with a left-middle-right three-section plunger, a reset spring 2.2 is arranged between the top end of each left-middle-section plunger and the bottom of each valve sleeve 2.1, each reset spring 2.2 acts on two ends of each compensation valve core 2.3, so that each compensation valve core 2.3 is centered in each valve sleeve 2.1, a left throttling opening 2.4 is formed between the middle-section plunger of each compensation valve core 2.3 and the left side of each valve sleeve, a right throttling opening 2.5 is formed between each middle-section plunger and the right side of each valve sleeve, and each left; the opening degree change trends of the left throttle orifice 2.4 and the right throttle orifice 2.5 in the flow compensation unit 2 are opposite; the inlet of the left throttle orifice 2.4 and the left spring cavity are connected with the outlet of a left controllable throttle orifice in the variable speed flow distribution unit 1, oil in the left controllable throttle orifice enters the left pressure compensation valve 3.1 through the left throttle orifice 2.4, the inlet of the right throttle orifice 2.5 and the right spring cavity are connected with the outlet of a right controllable throttle orifice 1.3 in the variable speed flow distribution unit 1, and the oil in the right controllable throttle orifice enters the right pressure compensation valve 3.2 through the right throttle orifice 2.5; the compensating valve core 2.3 keeps balance under the action of spring force and hydraulic pressure to change the opening degrees of the left throttling port 2.4 and the right throttling port 2.5, so that the hydraulic resistance of a left branch and a right branch connected with the compensating valve core is adjusted, the opening degrees of the left throttling port 2.4 and the right throttling port 2.5 are adjusted by depending on the displacement of the compensating valve core 2.3, one of the opening degrees of the two throttling ports is increased, the other one of the opening degrees of the two throttling ports is decreased, and the change trends are opposite.

The pressure compensation unit 3 comprises a left pressure compensation valve 3.1 and a right pressure compensation valve 3.2 which are arranged side by side, the models of the left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 are BLF10, the model of the shuttle valve 3.3 is VU2P, oil inlets of the left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 are respectively connected with outlet pipelines of a left throttle opening 2.4 and a right throttle opening 2.5 in the flow compensation unit 2, oil outlets of the left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 are respectively connected with two driving oil cylinders, the left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 are also connected with the shuttle valve 3.3, the oil outlets of the left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 are respectively connected with the left oil inlet and the right oil inlet of the shuttle valve 3.3, the hydraulic control ports of the left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 are respectively connected with the oil outlet of the shuttle valve 3.3, the oil outlet of the shuttle valve 3.3 is a port Ls, and the highest load pressure of the whole load sensitive flow divider valve is acquired.

A speed-changing synchronous driving system of the load-sensitive shunt valve is characterized in that a P port of a speed-changing shunt unit 1 is used as an oil inlet and is connected with a load-sensitive variable pump 4 through a pipeline, an A port and a B port of a pressure compensation unit 3 are connected with a left driving oil cylinder 6 and a right driving oil cylinder 7, and the A port and the B port are respectively connected with rod cavities of the left driving oil cylinder 6 and the right driving oil cylinder 7 through pipelines; the highest load pressure is fed back to the pressure feedback oil port of the load sensitive variable pump 4 through the load pressure feedback oil port Ls of the pressure compensation unit 3, and the highest load pressure is fed back to the left pressure compensation valve 3.1, the right pressure compensation valve 3.2 and the variable pump 4 through the shuttle valve 3.3, so that the load sensitive control is realized. The pressure feedback mode of the variable speed synchronous driving system comprises one of hydraulic feedback and electric feedback. The model of the load-sensitive variable pump 4 is A11 VODRS.

A working method of load sensitive shunt synchronous drive is used for realizing high-precision equivalent shunt under the working condition of large unbalance load or time-varying load, and the working method comprises the following steps:

firstly, the variable speed shunting unit 1 divides oil input by the load-sensitive pump 4 through a P port into a left branch and a right branch, and finally to a left controllable throttling orifice 1.2 and a right controllable throttling orifice 1.3, and the left branch flow Q is obtained by utilizing the left controllable throttling orifice 1.2 and the right controllable throttling orifice 1.3₁And right branch flow Q₂Changed to left side pressure P₁And right side pressure P₂(ii) a The opening degrees of the left controllable throttling port 1.2 and the right controllable throttling port 1.3 are manually changed, so that the total flow of the load sensitive flow divider valve 5 is changed, and the synchronous speed of the left driving oil cylinder 6 and the right driving oil cylinder 7 is further adjusted;

left side pressure P after diversion₁And right side pressure P₂The oil acts on two ends of the compensating valve core to push the valve core to move so as to adjust the hydraulic resistance of the two branches, thereby compensating the flow deviation of the two branches and leading the pressure P of the two branches₁＝P₂Flow rate Q₁＝Q₂；

The left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 are used for compensating the load deviation acting on the left driving oil cylinder 6 and the right driving oil cylinder 7, so that the unbalance loading becomes uniform, the influence of the unbalance loading on the shunting precision of the variable speed shunting unit 1 is thoroughly eliminated, and the large unbalance loading resistance of the load sensitive shunting valve 5 is further improved;

the shuttle valve 3.3 takes the highest load pressure of the system and feeds back the highest load pressure to the load sensitive variable pump 4 through a load feedback port, and the displacement of the load sensitive variable pump is changed through load sensitive control, so that the load sensitive variable pump outputs flow and pressure consistent with the load requirement, and the efficiency of the synchronous driving system and the capacity of resisting load change are further improved.

The method comprises the following specific steps:

a. speed change and flow distribution: firstly, the variable speed shunting unit 1 divides oil input by the load-sensitive pump 4 through the P port into a left branch and a right branch and finally to a left controllable throttling port 1.2 and a right controllable throttling port 1.3, and the left controllable throttling port 1.2 and the right controllable throttling port 1.3 are utilized to control the flow Q of the left branch and the right branch₁And Q₂Conversion to pressure P₁And P₂Flow of the left and right branchesThe amount is:wherein K is the valve coefficient, Q₁And Q₂Flow rates, x, of the left and right branches, respectively_v1And x_v1Respectively, the opening degree of the throttle opening is controlled left and right, and x_v1＝x_v2，P_sIs the pressure at port P, P₁Is the outlet pressure, P, of the left controllable restriction 1.2₂The outlet pressure of the right controllable throttle orifice 1.3 is adopted, and the flow Q of the left branch and the right branch is adjusted by changing the opening degrees of the left controllable throttle orifice 1.2 and the right controllable throttle orifice 1.3₁And Q₂Further changing the synchronous speed of the left driving oil cylinder 6 and the right driving oil cylinder 7;

b. flow compensation: the pressure after the diversion is P₁And P₂The two paths of oil respectively act on two ends of the compensating valve core 2.3 through pipelines to push the compensating valve core 2.3 to move so as to adjust the hydraulic resistance of the oil in the two branches, and finally the compensating valve core 2.3 is in a balanced state under the combined action of the spring force and the hydraulic pressure of the two return springs 2.2;

the equilibrium state is: (P)₁-P₂) Where a is the effective area of the left and right plungers of the compensator spool 2.3, K is the stiffness of the return spring 2.2, Δ x is the displacement of the compensator spool 2.3, and Δ x is the outlet pressure P of the left and right orifices 2.4, 2.5 of the compensator spool₃And P₄When | P is related to₃-P₄The smaller |, the smaller Δ x, and P₁And P₂The smaller the difference is, the smaller the flow Q of the two branches is₁And Q₂The closer the proximity, the higher the diversion accuracy of the load-sensitive diversion valve 5 is;

c. pressure compensation: setting the load pressure of different oil cylinders as P₅And P₆And P is₅≠P₆Shuttle valve 3.3 takes the maximum value P of the two load pressures of the two branches_m＝max(P₅,P₆) (ii) a If the left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 are in equilibrium, the inlet pressures of the left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 are substantially equal, i.e. P₃≈P₄＝P_m+P_kIn which P is_kThe preset pressure of the left pressure compensation valve 3.1 and the right pressure compensation valve 3.2 is balanced; due to the effect of pressure compensation, | P₃-P₄I is close to zero, Δ x is small, and therefore has P₁≈P₂At this time Q₁≈Q₂Therefore, the unbalance loading becomes uniform through pressure compensation, the influence of unbalance loading on the flow distribution precision is thoroughly eliminated, and the large unbalance loading resistance of the flow distribution valve is further improved;

d. load-sensitive control: shuttle valve 3.3 takes the highest load pressure P of the system_mAnd feeds back to the load-sensitive variable pump 4 through a load feedback port, under the action of load-sensitive control, the load-sensitive variable pump 4 changes the displacement, and the output flow is the sum Q of the total flows of the two branches₁+Q₂The output pressure is adapted to the highest load pressure P_s＝P_m+P_dIn which P is_dThe pressure margin is used, the pressure and the flow of the pump source can be consistent with the load requirement through the load sensitive control, so that the capacity of the synchronous system for resisting load change is improved, meanwhile, the overflow loss is reduced, and the efficiency of the synchronous driving system is improved.

The invention organically combines the structure and the principle of shunting synchronous drive and load sensitive control, establishes a dynamic working mechanism between a load and a shunting element and a pump source, provides the load sensitive shunting valve, the variable speed synchronous control system and the working method, can thoroughly eliminate the influence of unbalance loading on shunting precision, can resist the interference of time-varying load, and can realize variable speed synchronous drive with high precision, high efficiency and wide range.