Noise reduction device and method for an electronic expansion valve

Abstract

The application provides a noise reduction device and method of an electronic expansion valve, and the noise reduction device is used for reducing the noise of the electronic expansion valve, the electronic expansion valve is connected with a front wall metal plate of a vehicle through a mounting bracket, and the noise reduction device of the electronic expansion valve comprises a first noise reduction structure and a second noise reduction structure; the electronic expansion valve is connected with a controller through a stepping motor, the controller comprises a first control unit and a second control unit, and the first control unit and the second control unit control the stepping motor to reset and operate the electronic expansion valve through a first excitation mode and a second excitation mode respectively. When the electronic expansion valve produces noise due to stall during the reset process in the self-checking and adjusting process, the noise can be weakened, and the noise produced by the electronic expansion valve due to stall can be further weakened, so that a better riding experience is provided for customers.

Description

A noise reduction device and method for an electronic expansion valve Technical Field

[0001] This invention relates to the field of noise reduction technology, and in particular to a noise reduction device and method for an electronic expansion valve. Background Technology

[0002] With the rise of microcomputer control technology, mechatronics has become a new trend in the development of refrigeration systems. Electronic expansion valves, compared to thermostatic expansion valves, have evolved from mechanical control to computer control, fully reflecting this trend. In the field of air conditioning for new energy vehicles, electronic expansion valves are used to regulate system overcooling or overheating.

[0003] Currently, due to space constraints on the placement of heat pump air conditioning components in gasoline vehicles converted to electric vehicles, as well as aesthetic requirements for pipeline design, the electronic expansion valve is placed on the front bulkhead sheet metal. Because the electronic expansion valve generates a lot of noise during its power-on self-test and adjustment process, the sound is transmitted into the driver's cab, making it audible to customers and affecting their experience. Summary of the Invention

[0004] Therefore, the purpose of this invention is to provide a noise reduction device and method for an electronic expansion valve to overcome the shortcomings of the prior art.

[0005] To achieve the above objectives, the present invention provides a noise reduction device for an electronic expansion valve, used to reduce noise in the electronic expansion valve. The electronic expansion valve is connected to the front sheet metal of a vehicle via a mounting bracket. The noise reduction device includes a first noise reduction structure and a second noise reduction structure disposed on the mounting bracket.

[0006] The first noise reduction structure is used to reduce the vibration transmission between the mounting bracket and the front sheet metal;

[0007] The second noise reduction structure is used to reduce the vibration transmission between the mounting bracket and the electronic expansion valve;

[0008] The electronic expansion valve is connected to a controller via a stepper motor. The controller includes a first control unit and a second control unit. The first control unit and the second control unit control the stepper motor to reset and run the electronic expansion valve via a first excitation mode and a second excitation mode, respectively.

[0009] The beneficial effects of this invention are as follows: By setting a first noise reduction structure and a second noise reduction structure on the mounting bracket, the first noise reduction structure reduces the vibration transmission between the mounting bracket and the front sheet metal, and the second noise reduction structure reduces the vibration transmission between the electronic expansion valve and the mounting bracket. This reduces the noise generated when the electronic expansion valve stalls during the self-test and adjustment reset process. At the same time, the first control unit and the second control unit control the stepper motor in the first excitation mode and the second excitation mode, respectively, to control the reset and operation of the electronic expansion valve, further reducing the noise generated by the electronic expansion valve stalling and providing customers with a better riding experience.

[0010] Preferably, the controller is connected to the stepper motor via a hardwire.

[0011] Preferably, the controller uses a four-phase eight-step method to control the stepper motor.

[0012] Preferably, the first noise reduction structure includes a vibration-damping rubber sleeve.

[0013] Preferably, the second noise reduction structure is a sound-insulating felt.

[0014] To achieve the above objectives, the present invention also provides a noise reduction method for an electronic expansion valve, the method comprising:

[0015] When the electronic expansion valve is powered on, the stepper motor is controlled to work in the first excitation mode so that the stepper motor drives the electronic expansion valve to reset and close the valve according to the first path.

[0016] After the reset is completed, the stepper motor is controlled to work in the second excitation mode so that the stepper motor drives the electronic expansion valve to open the valve by running along the second path.

[0017] Preferably, the first excitation method includes a first specific pulse step count and a first excitation rate, the first excitation rate being 100 PPS; the second excitation method includes a second specific pulse step count and a second excitation rate, the second excitation rate being 66.7 PPS; and both the first specific pulse step count and the second specific pulse step count are 550.

[0018] Preferably, the electronic expansion valve includes a stopper, a rotor, and a valve core. The step of controlling the stepper motor to operate in a first excitation mode so that the stepper motor drives the electronic expansion valve to reset along a first path includes:

[0019] The stepper motor is controlled to operate using the first excitation method, which drives the stop to rotate clockwise. Under the action of the magnetic field, the rotor rotates with the rotation of the stop and drives the valve core to move vertically away from the stop, so as to reset.

[0020] Preferably, the first excitation mode includes a first excitation timing sequence, which consists of four phases. The four phases are combined to form multiple step control signals, and each step control signal corresponds to a position of the rotor.

[0021] Preferably, the method further includes:

[0022] The stepper motor is controlled to work continuously with a preset number of pulse steps as a cycle.

[0023] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0024] Figure 1 is a schematic diagram of the electronic expansion valve in application state provided in the first embodiment of the present invention;

[0025] Figure 2 is a cross-sectional view of the electronic expansion valve provided in the first embodiment of the present invention when the valve is open;

[0026] Figure 3 is a schematic diagram of the connection of the four phases in the first excitation timing sequence provided in the first embodiment of the present invention;

[0027] Figure 4 is a diagram showing the correspondence between the excitation method and the on / off valve provided in the first embodiment of the present invention;

[0028] Figure 5 is a flowchart of the noise reduction method for the electronic expansion valve provided in the second embodiment of the present invention.

[0029] Explanation of key component symbols:

[0030] 10 Electronic expansion valve 20 Mounting bracket 11 Front sheet metal 30 Rotor 12 Stepper motor 40 Valve core 13 Controller 50 Valve port 14 surface

[0031] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0032] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Several embodiments of the invention are illustrated in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0033] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0035] Please refer to Figures 1 and 2, which show the noise reduction device for the electronic expansion valve in the first embodiment of the present invention. The device is used to reduce the noise of the electronic expansion valve 10. It is understood that due to space constraints on the arrangement of heat pump air conditioning parts in the conversion of fuel vehicles to electric vehicles, as well as the aesthetic requirements of pipeline design, the electronic expansion valve 10 is arranged in the front sheet metal 30. Because the electronic expansion valve 10 may stall during power-on self-test and adjustment, it will generate a large noise, which will be transmitted into the driver's cab and affect the passenger's riding experience. In order to improve the above problems, the noise reduction device for the electronic expansion valve includes a first noise reduction structure and a second noise reduction structure.

[0036] The first noise reduction structure and the second noise reduction structure are both mounted on the mounting bracket 20. The first noise reduction structure is used to reduce the vibration transmission between the mounting bracket 20 and the front sheet metal 30, and the second noise reduction structure is used to reduce the vibration transmission between the mounting bracket 20 and the electronic expansion valve 10. When the electronic expansion valve 10 stalls during power-on self-test and adjustment, it can effectively reduce the noise amplitude to improve the customer's riding experience. Furthermore, the electronic expansion valve 10 is generally connected to the controller 50 through the stepper motor 40. The controller 50 is electrically connected to the stepper motor 40, and the stepper motor 40 is connected to the electronic expansion valve 10. In order to improve the stall situation, the controller 50 includes a first control unit and a second control unit. The first control unit and the second control unit control the stepper motor 40 with the first excitation mode and the second excitation mode, respectively, to control the reset and operation of the electronic expansion valve 10.

[0037] Specifically, the controller 50 is connected to the stepper motor 40 via hardwired connection to achieve hardwired control of the stepper motor 40. Therefore, the controller 50 can only determine the operating status of the stepper motor 40 by observing the continuity of the circuit. To better control the stepper motor 40, the controller 50 employs a four-phase, eight-step method to control the stepper motor 40, based on the hardwired control. It should be noted that, as shown in Figure 3, the first excitation mode includes a first excitation timing sequence, which consists of four phases. These four phases combine to form various stepper control signals. The control signal corresponds to a position of the valve core 13 of the electronic expansion valve 10, as shown in Figure 4. This represents the state of each of the four phases in the first excitation sequence when the stepper motor 40 takes one step. A cross-section indicates that the phase is in the energized and conducting state, while no cross-section indicates that the phase is in the non-conducting state. Each column represents a step control signal. When the four phases are transmitted as step control signals from left to right, the electronic expansion valve is determined to be in the opening phase. When the four phases are transmitted as step control signals from right to left, the electronic expansion valve is determined to be in the closing phase.

[0038] It should be noted that the first excitation method also includes a first specific pulse step count and a first excitation rate. The first specific pulse step count is determined by the maximum pulse value of the stepper motor 40. In this embodiment, the maximum pulse value of the stepper motor 40 is 550, therefore, the first specific pulse step count is 550, and the first excitation rate is 100 PPS. The electronic expansion valve 10 includes a stopper 11, a rotor 12, and a valve core 13. The stopper 11 is magnetically connected to the rotor 12, and the rotor 12 is connected to the valve core 13. When the stepper motor is controlled to operate in the first excitation method, the electronic expansion valve 10 will reset according to the first path. That is, the stopper 11 of the electronic expansion valve 10 rotates clockwise with the stepper motor 40. Under the action of the magnetic field, it drives the rotor 12 to rotate downward, so as to drive the valve core 13 to move axially in a straight line away from the stopper 11, so as to block the valve port 14 of the electronic expansion valve 10. This continues until all the first specific pulse steps are completed, then the reset is completed, and then the normal operation is resumed. The movement of the valve core 13 away from the stopper 11 is the reverse movement, and its movement towards the stopper 11 is the forward movement. The electronic expansion valve 10 moves in the reverse direction to close the valve, and moves in the forward direction to open the valve.

[0039] It should be noted that the second excitation mode includes a second excitation timing sequence. The connection relationship of the four phases in the second excitation timing sequence is basically the same as that of the four phases in the first excitation timing sequence. The difference is that the second excitation timing sequence consists of eight step control signals transmitted sequentially from left to right as shown in Figure 4.

[0040] Understandably, when the electronic expansion valve 10 is powered on, it first needs to be reset, i.e., find zero, before it can start normal operation. The traditional reset method usually requires the electronic expansion valve 10 to be moved forward first, i.e., the stopper 11 is rotated counterclockwise to push the rotor 12 to rotate upward. The rotor 12 drives the valve core 13 to move upward in an axial linear motion until the valve core 13 reaches the top. The rotor 12 can no longer rotate upward even if it continues to rotate. At this time, it is in a stalled state. Then the electronic expansion valve 10 is adjusted to move in the reverse direction until it is successfully found zero and then it can operate normally.

[0041] It should be noted that since the controller 50 generally controls the stepper motor 40 to control the electronic expansion valve 10 through hard wiring, the working status of the stepper motor 40 can only be obtained through the continuity of the circuit. Therefore, the starting position of the electronic expansion valve 10 cannot be obtained, and the position of the electronic expansion valve 10 can only be determined manually. As a result, when the electronic expansion valve 10 is moving in the forward direction, the pulse step number of the stepper motor 40 needs to be repeatedly tried, which can easily lead to a long stall time. During the stall process, the rotor 12 will continuously rotate and collide with the valve core 13, which will produce a lot of noise. Compared with directly controlling the stepper motor 40 to work with the first excitation method in this embodiment, which directly drives the electronic expansion valve 10 to move in the reverse direction, the stall time can be effectively reduced, the noise situation can be improved, and the reset efficiency can also be improved.

[0042] In addition, the stepper motor 40 is controlled to operate using a second excitation method to control the operation of the electronic expansion valve 10. Specifically, the second excitation method includes a second pulse step count and a second excitation rate. The second pulse step count is 550, and the second excitation rate is 66.7 PPS. When the electronic expansion valve 10 is running, the corresponding excitation rate of the stepper motor 40 is usually 100 PPS to reduce noise decibels and improve stall noise.

[0043] In this embodiment, the first noise reduction structure is a vibration-damping rubber sleeve to reduce the stiffness of the end of the mounting bracket 20 that is connected to the front sheet metal 30, thereby reducing vibration transmission. The second noise reduction structure is a sound-insulating felt. It should be noted that the traditional mounting bracket 20 and the electronic expansion valve 10 are usually connected by bolts. In this embodiment, the bolt connection is eliminated, and sound-insulating felt is used for isolation to reduce the vibration transmission of the electronic expansion valve 10 to the mounting bracket 20 and the front sheet metal 30.

[0044] In practical implementation, by setting a first noise reduction structure and a second noise reduction structure on the mounting bracket 20, the first noise reduction structure reduces the vibration transmission between the mounting bracket 20 and the front sheet metal 30, and the second noise reduction structure reduces the vibration transmission between the electronic expansion valve 10 and the mounting bracket 20. This reduces the noise generated when the electronic expansion valve 10 stalls during the self-test and adjustment reset process. At the same time, the first control unit and the second control unit control the stepper motor 40 in the first excitation mode and the second excitation mode, respectively, to control the reset and operation of the electronic expansion valve 10, further reducing the noise generated by the electronic expansion valve 10 due to stalling, and providing customers with a better riding experience.

[0045] It should be noted that the above implementation process is only to illustrate the feasibility of this application, but it does not mean that the noise reduction device of the electronic expansion valve of this application has only the above-mentioned unique implementation process. On the contrary, as long as the noise reduction device of the electronic expansion valve of this application can be implemented, it can be included in the feasible implementation scheme of this application.

[0046] Please refer to 5, which describes a noise reduction method for an electronic expansion valve in the second embodiment of the present invention. This method is used to reduce noise in the electronic expansion valve 10, and employs a noise reduction device for the electronic expansion valve as described in the first embodiment. The method includes the following steps:

[0047] Step S101: When the electronic expansion valve 10 is powered on, the stepper motor 40 is controlled to work in the first excitation mode so that the stepper motor 40 drives the electronic expansion valve 10 to reset and close the valve according to the first path.

[0048] In step S102, after the reset is completed, the stepper motor 40 is controlled to work in the second excitation mode so that the stepper motor 40 drives the electronic expansion valve 10 to open the valve according to the second path.

[0049] It should be noted that the first excitation method also includes a first specific pulse step count and a first excitation rate. The first specific pulse step count is determined by the maximum pulse value of the stepper motor 40. In this embodiment, the maximum pulse value of the stepper motor 40 is 550, therefore, the first specific pulse step count is 550, and the first excitation rate is 100 PPS. The electronic expansion valve 10 includes a stopper 11, a rotor 12, and a valve core 13. The stopper 11 is magnetically connected to the rotor 12, and the rotor 12 is connected to the valve core 13. When the stepper motor is controlled to operate in the first excitation method, the electronic expansion valve 10 will reset according to the first path. That is, the stopper 11 of the electronic expansion valve 10 rotates clockwise with the stepper motor 40. Under the action of the magnetic field, it drives the rotor 12 to rotate downward, so as to drive the valve core 13 to move axially in a straight line away from the stopper 11, so as to block the valve port 14 of the electronic expansion valve 10. This continues until all the first specific pulse steps are completed, then the reset is completed, and then the normal operation is resumed. The movement of the valve core 13 away from the stopper 11 is the reverse movement, and its movement towards the stopper 11 is the forward movement. The electronic expansion valve 10 moves in the reverse direction to close the valve, and moves in the forward direction to open the valve.

[0050] Understandably, when the electronic expansion valve 10 is powered on, it first needs to be reset, i.e., find zero, before it can start normal operation. The traditional reset method usually requires the electronic expansion valve 10 to be moved forward first, i.e., the stopper 11 is rotated counterclockwise to push the rotor 12 to rotate upward. The rotor 12 drives the valve core 13 to move upward in an axial linear motion until the valve core 13 reaches the top. The rotor 12 can no longer rotate upward even if it continues to rotate. At this time, it is in a stalled state. Then the electronic expansion valve 10 is adjusted to move in the reverse direction until it is successfully found zero and then it can operate normally.

[0051] It should be noted that since the controller 50 generally controls the stepper motor 40 to control the electronic expansion valve 10 through hard wiring, the working status of the stepper motor 40 can only be obtained through the continuity of the circuit. Therefore, the starting position of the electronic expansion valve 10 cannot be obtained, and the position of the electronic expansion valve 10 can only be determined manually. As a result, when the electronic expansion valve 10 is moving in the forward direction, the pulse step number of the stepper motor 40 needs to be repeatedly tried, which can easily lead to a long stall time. During the stall process, the rotor 12 will continuously rotate and collide with the valve core 13, which will produce a lot of noise. Compared with directly controlling the stepper motor 40 to work with the first excitation method in this embodiment, which directly drives the electronic expansion valve 10 to move in the reverse direction, the stall time can be effectively reduced, the noise situation can be improved, and the reset efficiency can also be improved.

[0052] In this embodiment, the electronic expansion valve 10 includes a stopper 11, a rotor 12, and a valve core 13. The stopper 11 is magnetically connected to the rotor 12, and the rotor 12 is connected to the valve core 13. The step of controlling the stepper motor 40 to work in a first excitation mode so that the stepper motor 40 drives the electronic expansion valve 10 to reset along a first path includes:

[0053] The stepper motor 40 is controlled to work in the first excitation mode to drive the stop 11 to rotate clockwise. Under the action of the magnetic field, the rotor 12 rotates with the rotation of the stop 11 and drives the valve core 13 to move vertically in a direction away from the stop 11 to reset.

[0054] In this embodiment, the first excitation method includes a first excitation timing sequence, which consists of four phases. The four phases are combined to form multiple step control signals, each of which corresponds to a position of the rotor 12. It should be noted that the second excitation method includes a second excitation timing sequence, which is substantially the same as the first excitation timing sequence.

[0055] In this embodiment, the method further includes:

[0056] The stepper motor 40 is controlled to work continuously with a preset number of pulse steps as a cycle.

[0057] The preset pulse step count is 8, meaning that 8 pulse steps constitute a cycle to control the stepper motor 40 to work continuously.

[0058] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0059] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A noise reduction method for an electronic expansion valve, comprising a noise reduction device for the electronic expansion valve, the device being used to reduce noise in the electronic expansion valve, wherein the electronic expansion valve is connected to the front sheet metal of a vehicle via a mounting bracket, characterized in that... The noise reduction device includes a first noise reduction structure and a second noise reduction structure mounted on the mounting bracket; the first noise reduction structure is used to reduce the vibration transmission between the mounting bracket and the front sheet metal; the second noise reduction structure is used to reduce the vibration transmission between the mounting bracket and the electronic expansion valve; the electronic expansion valve is connected to a controller via a stepper motor, the controller includes a first control unit and a second control unit, the first control unit and the second control unit respectively control the stepper motor to reset and run the electronic expansion valve through a first excitation mode and a second excitation mode; the method includes: when the electronic expansion valve is powered on... The stepper motor is controlled to operate under a first excitation mode, so that the stepper motor drives the electronic expansion valve to reset and close the valve according to a first path. After the reset is completed, the stepper motor is controlled to operate under a second excitation mode, so that the stepper motor drives the electronic expansion valve to operate and open the valve according to a second path. The first excitation mode includes a first specific pulse step count and a first excitation rate, the first excitation rate being 100 PPS. The second excitation mode includes a second specific pulse step count and a second excitation rate, the second excitation rate being 66.7 PPS. Both the first specific pulse step count and the second specific pulse step count are 550.

2. The noise reduction method for the electronic expansion valve according to claim 1, characterized in that, The controller is connected to the stepper motor via a hardwire.

3. The noise reduction method for the electronic expansion valve according to claim 1, characterized in that, The controller uses a four-phase, eight-step method to control the stepper motor.

4. The noise reduction method for the electronic expansion valve according to claim 1, characterized in that, The first noise reduction structure includes a vibration-damping rubber sleeve.

5. The noise reduction method for the electronic expansion valve according to claim 1, characterized in that, The second noise reduction structure is sound-insulating felt.

6. The noise reduction method for the electronic expansion valve according to claim 1, characterized in that, The electronic expansion valve includes a stop, a rotor, and a valve core. The step of controlling the stepper motor to operate in a first excitation mode so that the stepper motor drives the electronic expansion valve to reset along a first path includes: controlling the stepper motor to operate in a first excitation mode so as to drive the stop to rotate clockwise. Under the action of the magnetic field, the rotor rotates with the rotation of the stop and drives the valve core to move linearly away from the stop in a direction to reset.

7. The noise reduction method for the electronic expansion valve according to claim 6, characterized in that, The first excitation mode includes a first excitation timing sequence, which consists of four phases. The four phases are combined to form multiple step control signals, and each step control signal corresponds to a position of the rotor.

8. The noise reduction method for the electronic expansion valve according to claim 1, characterized in that, The method further includes controlling the stepper motor to work continuously with a preset number of pulse steps as a cycle.

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