High pressure high volume compound controller device with flow control

Abstract

The application discloses a high-pressure large-displacement composite controller device with flow control, which comprises a shell, a variable piston, a return spring, a power control valve and a pressure control valve arranged in the shell, the power control valve and the pressure control valve are communicated with the large end and the small end of the variable piston through control oil paths, and the device is characterized in that the device further comprises a flow control valve, an oil inlet of the flow control valve is communicated with a high-pressure control oil path, and an oil outlet of the flow control valve is communicated with the large end of the variable piston through the power control valve; the flow control valve is provided with a feedback oil port; a valve core of the flow control valve moves based on the balance relationship between the feedback pressure of the feedback oil port and a preset spring force, so as to control the on-off of the high-pressure control oil path to the large end of the variable piston, and then the displacement of the pump is adjusted to stabilize the output flow. The device can significantly improve energy efficiency, improve the coordination of composite actions, enhance response speed and control accuracy, and meet the compactness requirement of high pressure and large flow.

Description

Technical Field

[0001] This invention relates to the field of hydraulic transmission and control technology, and in particular to a compact composite controller device for a high-pressure, large-displacement variable piston pump that integrates flow control, constant power control and remote pressure control functions. Background Technology

[0002] As a core power component of hydraulic systems, the control technology of hydraulic piston pumps directly affects the system's energy efficiency, dynamic response, and stability. In hydraulic systems of marine machinery and construction machinery, pumps often require constant power control to maximize engine power. For example, the constant power controller with pressure control for a high-pressure piston pump, as described in the applicant's previous patent application (CN222596231U), allows the main pump to automatically adjust its output flow based on the load pressure. When the system pressure increases, the pump reduces its displacement through a variable displacement mechanism, keeping the output power W=P×Q essentially constant, thus achieving high engine power utilization and high-pressure protection.

[0003] However, with the upgrading and iteration of mainframes, higher requirements are placed on piston pumps, necessitating compatibility with multiple control functions to further reduce energy consumption and adapt to complex operating conditions in various scenarios. Besides constant power control, under idling conditions, to reduce equipment energy loss, it is typically necessary to reduce system pressure and displacement to zero flow. Furthermore, in many applications (such as the stable propulsion of ceramic presses and forging presses), a constant pump output flow rate is required to ensure stable operation of the actuator.

[0004] Traditional hydraulic systems often use fixed displacement pumps or constant pressure variable displacement pumps, adjusting flow and pressure through relief valves or throttle valves. However, under conditions of frequent load fluctuations, such systems suffer from significant energy loss and temperature rise. The system's unused energy is converted into heat, which is not only an unrecoverable energy loss but also leads to increased system oil temperature, affecting system performance and component lifespan.

[0005] Currently, integrated flow controllers for common swashplate piston pumps are in use, but they are limited by factors such as pressure level, displacement size, and installation space, making it difficult to integrate the advantages of high pressure, large displacement, multiple composite control functions, and compact structure into one device. Therefore, there is an urgent need for a composite controller device that can integrate flow control, constant power control, and pressure control under high pressure and large displacement conditions, and has a compact structure and clear control priorities. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a high-pressure, high-displacement composite controller device that integrates flow control. This device aims to solve the problems of existing piston pumps being unable to simultaneously meet the requirements of high pressure (e.g., rated pressure above 35MPa), large displacement (e.g., maximum displacement 1000mL / r), integrate multiple control functions (flow control, constant power control, remote pressure control), and have a compact structure, thereby achieving high efficiency, energy saving, and precise control of the hydraulic system under complex working conditions.

[0007] The above-mentioned technical problems of the present invention are mainly solved by the following technical solution: a high-pressure, large-displacement composite controller device integrating flow control, comprising a housing, a variable piston disposed within the housing, a return spring connected to the small end (W) of the variable piston, a power control valve, and a pressure control valve, wherein the power control valve and the pressure control valve are respectively connected to the large end (Q) and the small end (W) of the variable piston through control oil circuits, characterized in that:

[0008] It also includes a flow control valve, the inlet of which is connected to a high-pressure control oil circuit, and the outlet of which is connected to the large end (Q) of the variable piston through a power control valve; the flow control valve is equipped with a feedback port (X), which is used to receive a feedback pressure signal related to the system output flow rate; the valve core of the flow control valve moves based on the balance relationship between the feedback pressure of the feedback port (X) and the preset spring force, so as to control the opening and closing of the high-pressure control oil circuit (b) to the large end (Q) of the variable piston, thereby adjusting the pump displacement to stabilize the output flow rate.

[0009] In the aforementioned high-pressure, high-displacement composite controller device with integrated flow control, preferably, the return port of the flow control valve is connected to the return oil circuit of the pump chamber; when the flow control valve is not working, the large end (Q) of the variable piston is connected to the return oil circuit of the pump chamber through the flow control valve.

[0010] In the aforementioned high-pressure, high-displacement composite controller device for flow control, preferably, one end of the valve core of the flow control valve is subjected to the oil pressure of the high-pressure control oil circuit (b), and the other end is subjected to the feedback pressure of the feedback oil port (X) and the preset spring force; the preset spring force is provided by small springs and large springs arranged in parallel or series.

[0011] In the aforementioned high-pressure, high-displacement composite controller device with integrated flow control, preferably, the high-pressure control oil circuit (b) originates from the oil inlet end of the power control valve or the high-pressure oil circuit at the pump outlet.

[0012] In the aforementioned high-pressure, high-displacement composite controller device for flow control, preferably, the feedback port (X) is connected to the inlet or outlet side of the system throttle valve to sense the pressure difference change across the throttle valve.

[0013] In the aforementioned high-pressure, high-volume composite controller device that integrates flow control, preferably, the flow control valve and the power control valve are arranged side by side on the housing.

[0014] In the aforementioned high-pressure, high-displacement composite controller device integrating flow control, preferably, the control priority of the composite controller device is as follows: the control function of the pressure control valve is the highest, followed by the control function of the power control valve, and the control function of the flow control valve is the lowest; when the system pressure reaches the set value of the pressure control valve, the pressure control valve operates, and the flow control valve and the power control valve exit control; when the system pressure reaches the set value of the power control valve but not the set value of the pressure control valve, the power control valve operates, and the flow control valve exits control.

[0015] In the aforementioned high-pressure, high-displacement composite controller device for flow control, preferably, the radial side of the variable piston is provided with a variable support, the end of the variable support is provided with a variable plunger, the variable plunger is in contact with a rotatable lever, and the other end of the lever is linked with the valve core of the power control valve.

[0016] A hydraulic system characterized by comprising a high-pressure, high-displacement composite controller device for integrated flow control as described above.

[0017] An engineering machine, including marine machinery, agricultural machinery, ceramic press or forging press, is characterized in that the hydraulic system of the engineering machine is equipped with a high-pressure, large-displacement composite controller device for flow control as described above.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] 1. Significantly improves energy efficiency: By controlling the flow rate, the pump's output flow rate is precisely matched with the actuator's requirements. By controlling the constant power, the engine power is fully utilized. By cutting off the pressure, high-pressure overflow loss is avoided. Compared with traditional systems, energy savings of 20% to 35% can be achieved, and system heat generation is effectively reduced.

[0020] 2. Improved coordination of compound actions: The flow control function ensures that the output of constant flow is unaffected by small fluctuations in load and speed when the actuator requires a stable flow, thereby improving the coordination of compound actions of multiple actuators and reducing pressure fluctuations.

[0021] 3. Enhanced response speed and control precision: Each control valve is directly integrated into the pump body, ensuring rapid response. The flow control valve adjusts in real time through feedback from the sensing throttling pressure difference, resulting in high control precision.

[0022] 4. Meets the requirements of high pressure, high flow and compact design: This device is based on a constant power controller structure with high pressure resistance and pressure control, inheriting its high pressure and high displacement characteristics. The flow control valve is integrated into it through optimized layout, which meets the stringent requirements of high pressure, high flow and space position in heavy load scenarios. Attached Figure Description

[0023] Figure 1 This is a hydraulic schematic diagram of the present invention.

[0024] Figure 2a This is a schematic diagram of the external shape of the flow control valve of the present invention (marked with X port).

[0025] Figure 2b This is a cross-sectional structural diagram of the flow control valve of the present invention.

[0026] Figure 3 This is a schematic diagram of the structure and arrangement of a plunger pump composite control valve according to the present invention.

[0027] Figure 4 This is a pressure-flow curve energy consumption comparison chart of the present invention.

[0028] The following are the labels in the diagram: 1. Oil supply component; 2. Return spring; 3. Power control valve; 4. Pressure control valve; 5. Remote relief valve; 6. Flow control valve; 7. Throttle valve; 601. Small spring; 602. Large spring; 603. Valve core; W. Small end of variable piston; Q. Large end of variable piston; b. High-pressure control oil; c. Pressure control oil; X. Feedback port. Detailed Implementation

[0029] The technical solution of the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

[0030] Reference Figure 1 , Figure 2a , Figure 2b and Figure 3 As shown, this embodiment provides a high-pressure, high-displacement composite controller device integrating flow control. This device is an integrated improvement based on a high-pressure resistant constant power controller device with pressure control (the basic structure of which can be referred to in CN222596231U). The variable piston has a variable support on its radial side, and a variable plunger is provided at the end of the variable support. The variable plunger (oil supply component 1) is in contact with a rotatable lever, and the other end of the lever is linked with the valve core of the power control valve 3.

[0031] Specifically, the device includes a housing, a variable piston housed within the housing, a return spring 2 connected to the small end (W) of the variable piston, a power control valve 3, and a pressure control valve 4. The power control valve 3 and the pressure control valve 4 are respectively connected to the large end (Q) and the small end (W) of the variable piston via control oil circuits. The core components of this device are the power control valve 3, the pressure control valve 4, and the newly added flow control valve 6.

[0032] The inlet of the flow control valve 6 is connected to a high-pressure control oil circuit (b), and the outlet of the flow control valve 6 is connected to the large end (Q) of the variable piston through the power control valve 3. The flow control valve 6 is equipped with a feedback port (X), which is connected to the inlet or outlet side of the system throttle valve 7. The feedback port (X) is used to receive feedback pressure signals related to the system output flow (sensing the pressure difference change across the throttle valve). The valve core 603 of the flow control valve 6 moves based on the balance between the feedback pressure of the feedback port (X) and the preset spring force to control the opening and closing of the high-pressure control oil circuit (b) to the large end (Q) of the variable piston, thereby adjusting the pump displacement to stabilize the output flow.

[0033] Furthermore, the integration of the flow control valve 6 is crucial. Internally, it houses a valve core 603. One end of the valve core 603 bears the hydraulic pressure from the high-pressure control oil circuit b, while the other end bears the hydraulic pressure from the feedback port X, as well as the spring force provided by the small spring 601 and the large spring 602. The inlet of the flow control valve 6 is connected to the high-pressure control oil circuit b, which can be drawn from the inlet of the power control valve 3 or the high-pressure oil circuit at the pump outlet. The outlet of the flow control valve 6 is connected to the power control valve 3, ultimately leading to the large end Q of the variable piston. Simultaneously, the flow control valve 6 has a return port, connected to the pump chamber (low-pressure chamber); when the flow control valve 6 is not operating, the large end (Q) of the variable piston is connected to the pump chamber return oil circuit through the flow control valve 6.

[0034] From a structural layout perspective, such as Figure 3 As shown, the flow control valve 6 and the power control valve 3 are arranged side by side on the pump's control housing. This layout is compact, makes full use of space, and makes the internal connecting oil passages as short as possible, reducing processing complexity and pressure loss.

[0035] In this embodiment, the control priority of the composite controller device is as follows: the pressure control valve 4 has the highest control function, followed by the power control valve 3, and the flow control valve 6 has the lowest control function. When the system pressure reaches the set value of the pressure control valve 4, the pressure control valve 4 is activated, and the flow control valve 6 and the power control valve 3 are deactivated; when the system pressure reaches the set value of the power control valve 3 but not the set value of the pressure control valve 4, the power control valve 3 is activated, and the flow control valve 6 is deactivated.

[0036] The working principle is as follows:

[0037] I. Flow control process:

[0038] When the main unit requires a stable flow rate, the system throttle valve 7 is put into use. The feedback port X of the flow control valve 6 is connected to the inlet or outlet of the throttle valve 7 (to sense the pressure difference across the throttle valve 7).

[0039] When the main engine speed increases instantaneously, the output flow rate of the oil supply component 1 pump increases instantaneously, causing the pressure difference across the throttle valve 7 to increase. This increased pressure difference is fed back as increased hydraulic pressure through port X. If the resultant force of this force and the spring force (small spring 601 and large spring 602) is insufficient to balance the pressure of high-pressure oil b on the other end of valve core 603, the high-pressure oil pushes valve core 603 to move, opening the oil circuit. High-pressure oil b then enters the large end Q of the variable piston through flow control valve 6 and power control valve 3. Since the effective area of ​​the large end Q is larger than that of the small end W, the variable piston moves in the direction of decreasing displacement, causing the pump's displacement Vg to decrease, and finally restoring the product of speed n and displacement Vg (i.e., output flow rate) to constant.

[0040] Conversely, when the main unit speed drops instantaneously, the pump output flow decreases, the pressure difference across the throttle valve 7 decreases, and the feedback pressure at port X decreases. The spring force (small spring 601 and large spring 602) pushes the valve core 603 to reset, cutting off the high-pressure oil b. The oil at the large end Q of the variable piston is discharged back to the pump chamber through the flow control valve 6. Under the action of the high-pressure oil at the small end W, the variable piston moves in the direction of increasing displacement, so that the output flow returns to constant.

[0041] The entire variable process takes a very short time, and the valve core 603 is in dynamic equilibrium, thus achieving a stable flow output.

[0042] II. Constant power control process:

[0043] When the system load pressure increases and reaches the set pressure of power control valve 3, the constant power control function is activated. At this time, the valve core of power control valve 3 reaches a new equilibrium under the action of hydraulic pressure and its own spring force, opening the oil circuit. High-pressure control oil b (the oil pressure in this circuit is related to the load pressure) enters the large end Q of the variable piston through power control valve 3, pushing the variable piston to move in the direction of reducing displacement.

[0044] According to the characteristics of power control valve 3, as the load pressure P increases, the displacement Q decreases accordingly, resulting in the pump's output power W = P. 出 ×Q 出 The power output remains essentially constant, thus making full use of the engine's power.

[0045] In this mode, since the system pressure is already high, the sum of the feedback pressure at the X port of the flow control valve 6 and the spring force cannot overcome the pressure of the high-pressure oil b. The valve core 603 is always in the open state, and the flow control function is automatically overridden (exit state).

[0046] III. Pressure Cut-off Control Process:

[0047] When the load pressure increases further and reaches the set value (system safety threshold or overload protection value) of pressure control valve 4 (usually connected to remote relief valve 5), pressure control valve 4 is activated. Pressure control oil c quickly enters the large end Q of the variable piston through pressure control valve 4, forcing the variable piston to move to the position where the displacement is zero, and the pump output flow drops to zero, thus realizing the pressure cut-off function.

[0048] In this state, the system pressure is at its highest, and both power control valve 3 and flow control valve 6 are out of control, giving pressure protection absolute priority.

[0049] Control priority summary: Pressure cutoff > Constant power control > Flow control. These three control modes automatically and seamlessly switch according to changes in system pressure, ensuring that the system operates in the most energy-efficient and safest manner under any operating conditions.

[0050] Figure 4 The pressure-flow curve energy consumption diagram shown intuitively illustrates the energy-saving effect of the present invention. Compared with the traditional fixed displacement pump system (whose energy consumption is roughly the rectangular area enclosed by the outer envelope of the constant power curve), the operating point of the present invention always changes along the constant power curve and the constant flow curve, avoiding unnecessary energy consumption in the high pressure and high flow area, thus significantly reducing the actual energy consumption of the system (the area enclosed by the curve) and achieving a significant energy-saving effect.

[0051] The composite controller device of the present invention is widely used in various fields such as marine machinery, agricultural machinery, steel, mining, machine tools, ceramic presses, and forging presses, and is particularly suitable for heavy equipment with stringent requirements for energy consumption, control accuracy, and space layout.

[0052] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A high-pressure, high-displacement composite controller device integrating flow control, comprising a housing, a variable piston disposed within the housing, a return spring (2) connected to the small end (W) of the variable piston, a power control valve (3), and a pressure control valve (4), wherein the power control valve and the pressure control valve are respectively connected to the large end (Q) and the small end (W) of the variable piston via control oil circuits, characterized in that: It also includes a flow control valve (6), the inlet of which is connected to a high-pressure control oil circuit (b), and the outlet of which is connected to the large end (Q) of the variable piston through a power control valve; the flow control valve is equipped with a feedback port (X), which is used to receive a feedback pressure signal related to the system output flow; the valve core (603) of the flow control valve moves based on the balance relationship between the feedback pressure of the feedback port (X) and the preset spring force, so as to control the opening and closing of the high-pressure control oil circuit (b) to the large end (Q) of the variable piston, thereby adjusting the pump displacement to stabilize the output flow; The return port of the flow control valve (6) is connected to the return oil circuit of the pump chamber; when the flow control valve is not working, the large end (Q) of the variable piston is connected to the return oil circuit of the pump chamber through the flow control valve; The high-pressure control oil circuit (b) originates from the oil inlet end of the power control valve (3) or the high-pressure oil circuit at the pump outlet; The feedback port (X) is connected to the inlet or outlet side of the system throttle valve (7) to sense the pressure difference change across the throttle valve.

2. The high-pressure, high-capacity composite controller device for integrated flow control according to claim 1, characterized in that, The valve core (603) of the flow control valve (6) is subjected to the oil pressure of the high pressure control oil circuit (b) at one end and the feedback pressure of the feedback oil port (X) and the preset spring force at the other end; the preset spring force is provided by a small spring (601) and a large spring (602) arranged in parallel or in series.

3. The high-pressure, large-capacity composite controller device for integrated flow control according to claim 1, characterized in that, The flow control valve (6) and the power control valve (3) are arranged side by side on the housing.

4. The high-pressure, large-capacity composite controller device for integrated flow control according to claim 1, characterized in that, The control priority of the composite controller device is as follows: the control function of the pressure control valve (4) is the highest, followed by the control function of the power control valve (3), and the control function of the flow control valve (6) is the lowest; when the system pressure reaches the set value of the pressure control valve, the pressure control valve works, and the flow control valve and the power control valve exit control; when the system pressure reaches the set value of the power control valve but not the set value of the pressure control valve, the power control valve works, and the flow control valve exits control.

5. The high-pressure, large-capacity composite controller device for integrated flow control according to claim 1, characterized in that, The variable piston has a variable support on its radial side, and a variable plunger is provided at the end of the variable support. The variable plunger is in contact with a rotatable lever, and the other end of the lever is linked to the valve core of the power control valve (3).

6. A hydraulic system, characterized in that: A high-pressure, high-displacement composite controller device comprising flow control as described in any one of claims 1 to 5.

7. An engineering machinery, including marine machinery, agricultural machinery, ceramic press or forging press, characterized in that: The hydraulic system of the engineering machinery is equipped with a high-pressure, large-displacement composite controller device for flow control as described in any one of claims 1 to 5.

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