A motor system and a working machine

Abstract

This invention provides a motor system and engineering machinery. The motor system includes: a pump, a motor, a cartridge valve, a control valve, a shuttle valve, and a control unit. The motor's inlet is connected to the pump's outlet via a first pipeline, and the motor's outlet is connected to the pump's inlet via a second pipeline. The cartridge valve has two working ports and one control port. One of the working ports is connected to the first pipeline, and the other is connected to the second pipeline. The control valve is connected to the control port and is used to control the opening and closing of the cartridge valve. The shuttle valve is configured to allow the hydraulic oil in the first pipeline and the hydraulic oil in the second pipeline with the higher oil pressure to enter the control valve. This invention addresses the technical problem of preventing excessive overturning moment caused by excessive motor operating speed.

Description

Technical Field

[0001] This invention relates to motor systems, and more particularly to a motor system and engineering machinery. Background Technology

[0002] Currently, closed-loop hydraulic systems are more commonly used in the hydraulic systems of engineering machinery and equipment. This means that the hydraulic oil circulation method is a hydraulic pump-hydraulic motor-hydraulic pump, and the hydraulic pump usually drives the hydraulic motor to rotate in both directions or in one direction.

[0003] The rotational speed of a hydraulic motor is determined by the amount of flow input to it. As the flow rate increases, the motor speed increases, and the overturning torque it bears also increases. This can affect the stability of the motor's operation and easily lead to problems such as leakage, vibration, and noise.

[0004] Therefore, it is necessary to limit the operating speed of the hydraulic motor to prevent excessive overturning torque caused by excessive motor operating speed. Summary of the Invention

[0005] This invention provides a motor system and engineering machinery to address the technical problem of preventing excessive overturning moment caused by excessive motor operating speed.

[0006] To achieve the above objectives, the present invention provides a motor system, comprising:

[0007] Pump;

[0008] The motor has its inlet connected to the outlet of the pump via a first pipe, and its outlet connected to the inlet of the pump via a second pipe.

[0009] A cartridge valve having two working ports and one control port, one of the two working ports being connected to the first pipeline and the other being connected to the second pipeline;

[0010] A control valve, which is connected to the control port, is used to control the opening and closing of the cartridge valve;

[0011] A shuttle valve, configured to allow the hydraulic oil in the first line and the hydraulic oil in the second line, with the higher oil pressure, to enter the control valve;

[0012] The control unit is configured to control the cartridge valve to open when the motor speed is greater than a preset value, so that the two working oil ports are connected to each other, and to control the cartridge valve to close when the motor speed is less than or equal to the preset value, so that the two working oil ports are blocked.

[0013] This invention provides a motor system in which, when the motor speed exceeds a preset value, a control valve opens a cartridge valve to connect two working ports, allowing hydraulic oil flowing in the first and second pipelines to pass through the cartridge valve. This reduces the flow rate to the motor, preventing it from tipping over due to excessive speed and protecting the motor. Conversely, when the motor speed is less than or equal to the preset value, the control valve closes the cartridge valve, preventing the first or second pipeline from connecting through it, thus reducing energy waste.

[0014] In one possible implementation, the control unit includes:

[0015] A speed detection device, used to detect the rotational speed of the motor;

[0016] A main control unit is electrically connected to the speed detection element and the control valve. The main control unit is used to control the control valve based on the speed information detected by the speed detection element.

[0017] In one possible implementation, the control unit further includes a signal amplifier electrically connected to the speed detection element and the main control unit, the signal amplifier being used to amplify the speed signal detected by the speed detection element.

[0018] In one possible implementation, the two inlets of the shuttle valve are connected to the first pipeline and the second pipeline, respectively, and the outlet of the shuttle valve is connected to the control valve.

[0019] In one possible implementation, one of the first pipeline and the second pipeline is a liquid outlet pipeline, and the other is a liquid return pipeline.

[0020] In one possible implementation, the cartridge valve is a two-way cartridge valve.

[0021] In one possible implementation, the control valve is a two-position three-way solenoid directional valve.

[0022] In one possible implementation, the speed detection element is a rotational speed sensor.

[0023] In one possible implementation, the motor has an end cap, and both the cartridge valve and the control valve are disposed on the end cap of the motor.

[0024] The present invention also provides an engineering machine, including the motor system described above.

[0025] The motor system provided by this invention has the advantages of simple structure, stable system, and low cost.

[0026] The present invention provides a motor system that can automatically control the opening and closing of a cartridge valve according to the motor speed, thereby achieving self-adjustment of the motor speed, preventing the motor speed from being too high, ensuring the stability and sealing of the motor system, and protecting the motor.

[0027] In addition to the technical problems solved by the embodiments of the present invention, the technical features constituting the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions as described above, other technical problems that can be solved by a motor system and engineering machinery provided by the embodiments of the present invention, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further described in detail in the specific embodiments. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 Hydraulic schematic diagram of a motor system provided for an embodiment of the present invention;

[0030] Figure 2 This is a block diagram of the control unit of the motor system provided in an embodiment of the present invention.

[0031] Explanation of reference numerals in the attached figures:

[0032] 10-pump;

[0033] 11-Motor;

[0034] 20-Motor;

[0035] 30 - Cartridge valve;

[0036] 31-Working oil port;

[0037] 32 - Control oil port;

[0038] 40 - Control valve;

[0039] 50-Shuttle valve;

[0040] 60 - First pipeline;

[0041] 70 - Second pipeline;

[0042] 80 - Control Unit;

[0043] 81-Speed ​​detection component;

[0044] 82-Main Controls;

[0045] 83 - Signal Amplifier;

[0046] 90-Fuel Tank;

[0047] 91-Third pipeline;

[0048] 92-Fourth pipeline;

[0049] 93-Fifth Pipeline;

[0050] 94 - Sixth Pipeline;

[0051] 95 - Seventh Pipeline;

[0052] 96-Eighth Pipeline. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0054] Typically, in hydraulic systems, there are certain limitations on the rotational speed of hydraulic motors. When the rotational speed of a hydraulic motor is too high, the overturning torque of the motor increases, which will affect the stability of the motor system.

[0055] In related technologies, two cartridge valves and two sets of directional valves are typically installed on the rear end cover of the motor to control the motor speed, which increases the cost. Considering that the motor speed is determined by the amount of flow into the motor, the motor speed increases when the amount of hydraulic oil passing through the motor increases. Therefore, the motor speed can be reduced by decreasing the amount of hydraulic oil in the motor, thus protecting the motor.

[0056] The present invention provides a motor system that can control the opening and closing of a cartridge valve according to the motor speed, thereby controlling the flow rate through the motor, realizing the self-regulation of motor speed, preventing the motor from tipping over due to excessive speed, and playing a role in protecting the motor.

[0057] The motor system and engineering machinery provided by embodiments of the present invention are described below with reference to the accompanying drawings.

[0058] refer to Figure 1 and Figure 2As shown, the present invention provides a motor system, including: a pump 10, a motor 20, a cartridge valve 30, a control valve 40, a shuttle valve 50, and a control unit 80, wherein the pump 10 is used to provide power to the hydraulic oil in the motor system; the inlet of the motor 20 is connected to the outlet of the pump 10 through a first pipeline 60, and the outlet of the motor 20 is connected to the inlet of the pump 10 through a second pipeline 70.

[0059] The cartridge valve 30 has two working ports 31 and one control port 32. One of the two working ports 31 is connected to the first pipeline 60, and the other is connected to the second pipeline 70.

[0060] Control valve 40 is connected to control port 32, and control valve 40 is used to control the opening and closing of cartridge valve 30.

[0061] The shuttle valve 50 is configured to allow the hydraulic oil in the first line 60 and the hydraulic oil in the second line 70 with the higher oil pressure to enter the control valve 40.

[0062] The control unit 80 is used to control the cartridge valve 30 to open via the control valve 40 when the speed of the motor 20 is greater than a preset value, so as to connect the two working oil ports 31 to each other, and to control the cartridge valve 30 to close via the control valve 40 when the speed of the motor 20 is less than or equal to the preset value, so as to block the connection between the two working oil ports 31.

[0063] The present invention provides a motor system in which, when the speed of the motor 20 exceeds a preset value, the control valve 40 controls the cartridge valve 30 to open, thereby connecting the two working oil ports 31. This allows hydraulic oil flowing in the first pipeline 60 and the second pipeline 70 to pass through the cartridge valve 30, reducing the flow rate to the motor 20 and preventing the motor 20 from tipping over due to excessive speed, thus protecting the motor 20. Conversely, when the speed of the motor 20 is less than or equal to the preset value, the control valve 40 controls the cartridge valve 30 to close, preventing the first pipeline 60 or the second pipeline 70 from connecting through the cartridge valve 30. This ensures the oil supply to the motor 20 and reduces energy waste.

[0064] Because the oil with the higher oil pressure at one of the two inlets of shuttle valve 50 is connected to the outlet of shuttle valve 50, and the oil pressure flowing out of the outlet of shuttle valve 50 is higher, the outlet of shuttle valve 50 is connected to control valve 40. This allows only the oil with the higher pressure in the first pipeline 60 and the second pipeline 70 to enter control valve 40, thereby controlling the opening of cartridge valve 30. Shuttle valve 50 can select the highest working pressure and transmit that pressure to control valve 40. Shuttle valve 50 has a compact structure, is not prone to leakage, and is easy to install.

[0065] Because the oil pressure in the outlet line of the motor system is greater than the oil pressure in the return line, the hydraulic oil in the outlet line can enter the outlet of the shuttle valve 50. This structure ensures the stable operation of the motor system regardless of whether either the first line 60 or the second line 70 is an outlet line.

[0066] In one possible implementation, the two inlets of the shuttle valve 50 are connected to the first pipeline 60 and the second pipeline 70, respectively, and the outlet of the shuttle valve 50 is connected to the control valve 40. The hydraulic oil entering the shuttle valve 50 drives the valve core of the shuttle valve 50 to switch, thereby changing the two inlets connected to the outlet of the shuttle valve 50.

[0067] In one possible implementation, one of the two inlets of the shuttle valve 50 is connected to the first pipeline 60 via a third pipeline 91, and the other of the two inlets of the shuttle valve 50 is connected to the second pipeline 70 via a fourth pipeline 92, and the outlet of the shuttle valve 50 is connected to the control valve 40 via a fifth pipeline 93.

[0068] It is easy to understand that the shuttle valve 50 also has the function of preventing the hydraulic oil in the control valve 40 from flowing backward into the first pipeline 60 and the second pipeline 70, thus ensuring the normal operation of the motor system.

[0069] In one possible implementation, one of the two working ports 31 of the cartridge valve 30 is connected to the first line 60 via a sixth line 94, and the other is connected to the second line 70 via a seventh line 95. The control valve 40 is connected to the control port 32 via an eighth line 96.

[0070] In one possible implementation, the third pipe 91, the fourth pipe 92, the fifth pipe 93, the sixth pipe 94, and the eighth pipe 96 can all be oil pipes.

[0071] In one possible implementation, the cartridge valve 30 can be adjusted to control pressure as needed, which is very convenient. When the oil pressure flowing from the control valve 40 into the cartridge valve 30 is greater than the elastic force of the pressure spring inside the cartridge valve 30, the valve core of the cartridge valve 30 moves, and the cartridge valve 30 opens. Conversely, when the oil pressure flowing from the control valve 40 into the cartridge valve 30 is less than the elastic force of the pressure spring inside the cartridge valve 30, the valve core of the cartridge valve 30 resets, and the cartridge valve 30 closes.

[0072] In one possible implementation, pump 10 is a hydraulic pump and motor 20 is a hydraulic motor, wherein pump 10 is driven by motor 11, and pump 10 provides hydraulic power to the motor system, thereby driving the flow of hydraulic oil.

[0073] In one possible implementation, pump 10 is a closed-loop hydraulic pump.

[0074] In one possible implementation method, refer to Figure 1 and Figure 2 As shown, the control unit 80 includes a speed detection element 81 and a main control element 82. The speed detection element 81 is used to detect the rotational speed of the motor 20. The main control element 82 is electrically connected to the speed detection element 81 and the control valve 40. The main control element 82 is used to control the control valve 40 according to the speed information detected by the speed detection element 81.

[0075] In one possible implementation, the main control 82 can control the circuit board. The main control 82 compares the speed detected by the speed detector 81 with a preset value. If the speed detected by the speed detector 81 is greater than the preset value, it sends a signal to the control valve 40, driving the electromagnet of the control valve 40 to actuate, causing the control valve 40 to control the cartridge valve 30 to open, thus connecting the two working ports 31. Conversely, if the speed detected by the speed detector 81 is less than or equal to the preset value, it does not send a signal to the control valve 40, and therefore the control valve 40 controls the cartridge valve 30 to remain closed, so that the two working ports 31 remain blocked.

[0076] After the electromagnet of the control valve 40 is activated, the hydraulic oil entering the outlet of the shuttle valve 50 can flow through the control valve 40 to the control port 32 of the cartridge valve 30. The hydraulic oil entering the control port 32 of the cartridge valve 30 drives the valve core of the cartridge valve 30 to move, thereby connecting the two working ports 31.

[0077] The size of the preset value can be flexibly selected according to the needs of use, and no specific limit is made here.

[0078] In one possible implementation, the control unit 80 further includes a signal amplifier 83 electrically connected to the speed detection element 81 and the main control unit 82. The signal amplifier 83 amplifies the speed signal detected by the speed detection element 81. When the signal passes through the signal amplifier 83, the signal is amplified and transmitted to the control valve 40, causing the electromagnet of the control valve 40 to actuate.

[0079] In one possible implementation, one of the first pipe 60 and the second pipe 70 is a liquid outlet pipe, and the other is a liquid return pipe.

[0080] In one possible implementation, where the first pipeline 60 is the outlet pipeline and the second pipeline 70 is the return pipeline, the hydraulic oil output by the pump 10 flows to the motor 20 through the first pipeline 60 and then flows to the pump 10 through the second pipeline 70.

[0081] When the speed of motor 20 is less than or equal to the preset value, the electrical signal transmitted to control valve 40 is small and cannot drive the electromagnet of control valve 40 to move. The two working ports 31 of cartridge valve 30 are blocked. The hydraulic oil in the first pipeline 60 cannot flow to the second pipeline 70 through cartridge valve 30, but can only flow to the second pipeline 70 through motor 20, thus ensuring the flow rate input to motor 20 and the speed of motor 20.

[0082] Conversely, when the speed of motor 20 exceeds the preset value, the electrical signal transmitted to control valve 40 can drive the electromagnet of control valve 40 to actuate. Hydraulic oil entering control valve 40 from shuttle valve 50 flows into cartridge valve 30, causing the valve core of cartridge valve 30 to move. The two working ports 31 of cartridge valve 30 are connected to each other. A portion of the hydraulic oil in the first pipeline 60 can flow to the second pipeline 70 through motor 20, and another portion of the hydraulic oil in the first pipeline 60 can flow to the second pipeline 70 through cartridge valve 30. This diverts the hydraulic oil in the first pipeline 60, reducing the flow to motor 20, thereby effectively preventing motor 20 from rotating too fast and protecting motor 20, thus ensuring the safe operation of the motor system.

[0083] In another possible implementation, where the first pipeline 60 is a return pipeline and the second pipeline 70 is a discharge pipeline, the hydraulic oil output by the pump 10 flows to the motor 20 through the second pipeline 70 and then flows to the pump 10 through the first pipeline 60.

[0084] When the speed of motor 20 is less than or equal to the preset value, the electrical signal transmitted to control valve 40 is small and cannot drive the electromagnet of control valve 40 to move. The two working ports 31 of cartridge valve 30 are blocked. The hydraulic oil in the second pipeline 70 cannot flow to the first pipeline 60 through cartridge valve 30, but can only flow to the first pipeline 60 through motor 20, thus ensuring the flow rate input to motor 20 and the speed of motor 20.

[0085] Conversely, when the speed of motor 20 exceeds the preset value, the electrical signal transmitted to control valve 40 can drive the electromagnet of control valve 40 to actuate, and the hydraulic oil entering control valve 40 flows into cartridge valve 30, causing the valve core of cartridge valve 30 to move. The two working ports 31 of cartridge valve 30 are connected to each other. A portion of the hydraulic oil in the second pipeline 70 can flow to the first pipeline 60 through motor 20, and another portion of the hydraulic oil in the second pipeline 70 can flow to the first pipeline 60 through cartridge valve 30. This diverts the hydraulic oil in the second pipeline 70, reducing the flow to motor 20, thereby effectively preventing motor 20 from rotating too fast and protecting motor 20, thus ensuring the safe operation of the motor system.

[0086] In one possible implementation, the first conduit 60 and the second conduit 70 can be oil pipes.

[0087] In one possible implementation, the cartridge valve 30 is a two-way cartridge valve. The cartridge valve 30 has the advantages of high flow pressure, low pressure loss, and stable operation, making it suitable for high-flow-rate systems.

[0088] In one possible implementation, the control valve 40 is a two-position three-way solenoid directional valve. Control is achieved through electronic control logic. When the speed of the motor 20 is detected to be greater than a preset value, the electromagnet of the control valve 40 is directly driven, causing the control valve 40 to switch from the normally closed state to the open state.

[0089] In one possible implementation, the speed detection element 81 is a rotational speed sensor.

[0090] The speed sensor outputs a frequency signal, which generates a square wave signal by detecting the output shaft speed or the number of teeth on the output shaft of motor 20. The higher the speed of motor 20, the higher the frequency of the signal. When the speed of motor 20 is low, the frequency signal of the speed sensor is small, and the pulse width modulation (PWM) signal generated by amplifier 53 is insufficient to generate enough current to control the electromagnet of valve 40, thus failing to control the opening of cartridge valve 30.

[0091] In one possible implementation, an oil tank 90 is also included, with the control valve 40 connected to the oil tank 90 and the motor 20 connected to the oil tank 90. ​​The oil tank 90 is used to store hydraulic oil.

[0092] In one possible implementation, the motor 20 has an end cap, and the cartridge valve 30 and control valve 40 are both mounted on the end cap of the motor 20. This helps to save installation space.

[0093] The present invention also provides an engineering machine, including the motor system described above.

[0094] The engineering machinery provided by this invention can be a device that uses the above-mentioned motor system.

[0095] This invention provides a motor system and engineering machinery, which have the advantages of simple structure, stable system, and low cost.

[0096] This invention provides a motor system and engineering machinery that can automatically control the opening and closing of the cartridge valve 30 according to the speed of the motor 20, thereby achieving self-adjustment of the motor 20 speed, preventing oil leakage and excessive overturning torque caused by excessive motor speed, protecting the motor 20, and ensuring the stability of the motor system operation.

[0097] In the description of this invention, it should be understood that the terms "center," "length," "width," "thickness," "top," "bottom," "upper," "lower," "left," "right," "front," "rear," "vertical," "horizontal," "inner," "outer," "axial," and "circumferential," etc., used to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the indicated position or component must have a specific orientation, or a specific structure and operation, and therefore should not be construed as a limitation of this invention.

[0098] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0099] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0100] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A motor system, characterized in that, include: Pump (10); Motor (20), the inlet of the motor (20) is connected to the outlet of the pump (10) through a first pipe (60), and the outlet of the motor (20) is connected to the inlet of the pump (10) through a second pipe (70); Cartridge valve (30) having two working ports (31) and one control port (32), one of the two working ports (31) being connected to the first pipeline (60) and the other being connected to the second pipeline (70); A control valve (40) is connected to the control port (32), and the control valve (40) is used to control the opening and closing of the cartridge valve (30); A shuttle valve (50) is configured such that the hydraulic oil in the first line (60) and the hydraulic oil in the second line (70) with the greater oil pressure enters the control valve (40). The control unit (80) is used to control the cartridge valve (30) to open through the control valve (40) when the speed of the motor (20) is greater than a preset value, so that the two working ports (31) are connected to each other, and to control the cartridge valve (30) to close through the control valve (40) when the speed of the motor (20) is less than or equal to the preset value, so that the two working ports (31) are blocked.

2. The motor system according to claim 1, characterized in that, The control unit (80) includes: Speed ​​detection element (81), the speed detection element (81) is used to detect the rotational speed of the motor (20); The main control (82) is electrically connected to the speed detection element (81) and the control valve (40). The main control (82) is used to control the control valve (40) based on the speed information detected by the speed detection element (81).

3. The motor system according to claim 2, characterized in that, The control unit (80) further includes a signal amplifier (53), which is electrically connected to the speed detection device (81) and the main control unit (82). The signal amplifier (83) is used to amplify the speed signal detected by the speed detection device (81).

4. The motor system according to any one of claims 1-3, characterized in that, The two inlets of the shuttle valve (50) are connected to the first pipeline (60) and the second pipeline (70) respectively, and the outlet of the shuttle valve (50) is connected to the control valve (40).

5. The motor system according to any one of claims 1-3, characterized in that, One of the first pipeline (60) and the second pipeline (70) is a liquid outlet pipeline, and the other is a liquid return pipeline.

6. The motor system according to any one of claims 1-3, characterized in that, The cartridge valve (30) is a two-way cartridge valve.

7. The motor system according to any one of claims 1-3, characterized in that, The control valve (40) is a two-position three-way solenoid directional valve.

8. The motor system according to any one of claims 2-3, characterized in that, The speed detection component (81) is a rotational speed sensor.

9. The motor system according to any one of claims 1-3, characterized in that, The motor (20) has an end cap, and the cartridge valve (30) and the control valve (40) are both disposed on the end cap of the motor (20).

10. An engineering machinery, characterized in that, Includes the motor system described in any one of claims 1-9.

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