Stirling refrigerating machine with adjustable working medium pressure and refrigeration control method

Abstract

The present application relates to a kind of Stirling refrigerators with adjustable working medium pressure and refrigeration control method, it includes: gas inlet container, for storing working medium gas;Gas inlet valve assembly, respectively communicate the gas inlet container and the back pressure chamber of the expander of Stirling refrigerator;And controller, it is connected the gas inlet valve assembly, and for receiving the temperature information of the expansion chamber of Stirling refrigerator;When the temperature of the expansion chamber of Stirling refrigerator is not in the preset temperature range, the opening of the gas inlet valve assembly is controlled by the controller, so that the working medium gas in gas inlet container enters back pressure chamber.The present application can combine working medium pressure regulation and motor operating state control to achieve rapid cooling, and can reduce the mechanical load of motor while ensuring refrigeration effect.

Description

Technical Field

[0001] This invention relates to the field of Stirling refrigerators, and more particularly to a Stirling refrigerator with adjustable working fluid pressure and a refrigeration control method. Background Technology

[0002] When a Stirling refrigerator operates, the pressure of the gaseous working fluid is constant. Therefore, during expander temperature regulation, the controller is often used to adjust the motor's operating state, thereby regulating the cooling capacity. For example, when the motor is a rotary motor, the controller can obtain the temperature inside the expansion chamber in real time. When the temperature has not reached the preset value (i.e., the initial cooling stage), the controller increases the rotary motor's speed to further increase the cooling capacity and achieve rapid cooling. When the temperature inside the expansion chamber reaches the preset value (i.e., the temperature control stage), the controller reduces the rotary motor's speed and maintains it at a constant level, further ensuring that the expansion chamber temperature remains unchanged at the preset value. Similarly, when the motor is a linear motor, during the initial cooling stage, the controller increases the linear motor's stroke to achieve rapid cooling, and during the temperature control stage, it reduces the linear motor's stroke to achieve constant temperature control.

[0003] However, the above temperature control method only achieves this by adjusting the working state of the motor, resulting in low overall efficiency and excessive load on the motor, which affects the lifespan and reliability of the refrigeration unit. Summary of the Invention

[0004] The purpose of this invention is to provide a Stirling refrigerator with adjustable working fluid pressure and a refrigeration control method, which can combine working fluid pressure regulation with motor operating status control to achieve rapid cooling and reduce the mechanical load on the motor while ensuring the refrigeration effect.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] On the one hand, a Stirling refrigerator with adjustable working fluid pressure is provided, comprising:

[0007] An inlet container, used to store the working gas;

[0008] An intake valve assembly, which is connected to the intake container and the back pressure chamber of the expander of the Stirling refrigerator, respectively;

[0009] And a controller, which is connected to the intake valve assembly and is used to receive expansion chamber temperature information from the Stirling refrigerator;

[0010] When the temperature of the expansion chamber of the Stirling refrigerator is not within the preset temperature range, the controller controls the opening of the intake valve assembly, so that the working gas in the intake container enters the back pressure chamber.

[0011] Preferably, when the working gas in the intake container enters the back pressure chamber, and when the motor of the Stirling refrigerator is a rotary motor, the controller controls the motor to rotate continuously at a first speed; when the motor of the Stirling refrigerator is a linear motor, the controller controls the motor to move continuously according to a first stroke.

[0012] Preferably, the Stirling refrigerator further includes:

[0013] An outlet container, used to store the working gas flowing out of the back pressure chamber;

[0014] An exhaust valve assembly is connected to the exhaust container and the back pressure chamber of the expander of the Stirling refrigerator, respectively, and is also connected to the controller;

[0015] When the temperature of the expansion chamber is within the preset temperature range, the controller controls the opening of the outlet valve assembly, so that the working gas in the back pressure chamber enters the outlet container.

[0016] Preferably, when the temperature of the expansion chamber is within a preset temperature range, and when the motor of the Stirling refrigerator is a rotary motor, the controller controls the motor to rotate continuously at a second speed; when the motor of the Stirling refrigerator is a linear motor, the controller controls the motor to move continuously according to a second stroke, so as to maintain the temperature of the expansion chamber within the preset temperature range.

[0017] Preferably, the first rotational speed is greater than the second rotational speed, and the first stroke is greater than the second stroke.

[0018] Preferably, the Stirling refrigerator further includes:

[0019] A pressure sensor, which is mounted on the expander, is used to acquire pressure changes within the back pressure chamber.

[0020] Preferably, the intake valve assembly is closed when the pressure in the back pressure chamber increases to the upper pressure threshold, and / or the outlet valve assembly is closed when the pressure in the back pressure chamber decreases to the lower pressure threshold.

[0021] On the other hand, a refrigeration control method based on a Stirling refrigerator is also provided, which includes the following steps:

[0022] When the expansion chamber temperature is not within the preset temperature range, the controller receives the expansion chamber temperature information and controls the opening of the intake valve assembly according to the expansion chamber temperature, so that the working gas in the intake container enters the back pressure chamber of the expander of the Stirling refrigerator.

[0023] When the temperature of the expansion chamber is within the preset temperature range, the controller controls the opening of the outlet valve assembly, allowing the working gas in the back pressure chamber of the Stirling refrigerator's expander to enter the outlet container.

[0024] Preferably, when the expansion chamber temperature is not within the preset temperature range, and when the motor of the Stirling refrigerator is a rotary motor, the controller controls the motor to rotate continuously at a first speed; when the motor of the Stirling refrigerator is a linear motor, the controller controls the motor to move continuously according to a first stroke.

[0025] In addition, when the expansion chamber temperature is within the preset temperature range, and when the motor of the Stirling refrigerator is a rotary motor, the controller controls the motor to rotate continuously at a second speed; when the motor of the Stirling refrigerator is a linear motor, the controller controls the motor to move continuously according to a second stroke, so as to maintain the expansion chamber temperature within the preset temperature range.

[0026] Furthermore, the first rotational speed is greater than the second rotational speed, and the first stroke is greater than the second stroke.

[0027] Preferably, the intake valve assembly is closed when the pressure in the back pressure chamber increases to the upper pressure threshold, and / or the outlet valve assembly is closed when the pressure in the back pressure chamber decreases to the lower pressure threshold.

[0028] In summary, the present invention has the following advantages compared with the prior art:

[0029] This invention combines working fluid pressure regulation with motor operating status control to reduce the expansion chamber temperature to a preset temperature range in a short time. Furthermore, by combining the low speed / short stroke operating state of the motor with the reduction of working fluid pressure, the motor can maintain the expansion chamber temperature within a low temperature range under low speed / short stroke conditions, thereby reducing the mechanical load on the motor while ensuring the cooling effect. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of a Stirling refrigerator in the prior art.

[0031] Figure 2 This is a schematic diagram of the overall structure of the Stirling refrigerator in this invention. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0033] Example 1

[0034] like Figure 2 As shown, this embodiment provides a Stirling refrigerator with adjustable working fluid pressure. The Stirling refrigerator can be a linear Stirling refrigerator or a rotary Stirling refrigerator, such as... Figure 1 As shown, the Stirling refrigerator mainly includes: a motor 1, connecting pipes 3, a cold finger 4, a cold accumulator 5, an expansion piston 6, and a spring 7. The cold accumulator 5 (including a cold accumulator shell and energy storage material, such as a metal wire mesh, filled within the shell) is assembled inside the cold finger 4 to form an expansion chamber 41 and a room temperature chamber 43 at both ends of the cold finger 4. Simultaneously, a back pressure chamber 42 is formed at the end of the cold finger 4 furthest from the expansion chamber 41 (for example, formed by the expansion chamber shell, piston 6, and end caps). The expansion piston 6 and the spring 7 are both located within the back pressure chamber 42. 6 connects to spring 7; the connecting pipe 3 connects to compression chamber 21 and room temperature chamber 43 respectively. The motor 1 is used to drive expansion piston 6 and spring 7 to move synchronously in a linear motion. For example, when the motor 1 is a rotary motor, compression piston 2 is set in compression chamber 21, and motor 1 is connected to compression piston 2 and expansion piston 6 through an eccentric structure, so that the gas working medium enters back pressure chamber 42 through connecting pipe 3 through the periodic movement of compression piston 2, so as to drive expansion piston 6 and spring 7 to move synchronously in a linear motion. When motor 1 is a linear motor, it can directly drive expansion piston 6 and spring 7 to move synchronously in a linear motion, thereby compressing the working medium gas and causing it to enter cold finger 4.

[0035] In addition, the Stirling refrigerator also includes:

[0036] An inlet container 100 is used to store a working gas at a gas pressure of P1; in this embodiment, the inlet container 100 may be made of steel.

[0037] The intake valve assembly 10 is connected to the intake container 100 and the back pressure chamber 42 of the expander of the Stirling refrigerator, respectively.

[0038] Pressure sensor 9, which is installed on the expander and connected to the controller 8, is used to acquire the pressure in the back pressure chamber 42 in real time;

[0039] And controller 8, which is connected to the intake valve assembly 10 and is used to receive the expansion chamber temperature information of the Stirling refrigerator;

[0040] During the initial cooling stage (i.e., when the expansion chamber temperature is not within the preset temperature range), the controller 8 receives the expansion chamber temperature information of the Stirling refrigerator in real time, and controls the opening of the air intake valve assembly 10 according to the expansion chamber temperature, so that the working gas in the air intake container 100 enters the back pressure chamber 42 to increase the pressure in the back pressure chamber 42. At the same time, when the motor 1 is a rotary motor, the controller 8 controls the motor 1 to rotate continuously at a first speed. When the motor 1 is a linear motor, the controller 8 controls the motor 1 to move continuously according to the first stroke. This process is the inflation process.

[0041] During inflation, the pressure sensor 9 acquires the pressure change in the back pressure chamber 42 in real time. When the pressure in the back pressure chamber 42 increases to the upper pressure threshold, the pressure sensor 9 feeds back the pressure in the back pressure chamber 42 to the controller 8. The controller 8 closes the air intake valve assembly 10 according to the pressure in the back pressure chamber 42 to end the inflation process.

[0042] Therefore, as the motor 1 continues to work at a higher speed or a longer stroke (i.e., the first speed or the first stroke), the pressure in the back pressure chamber 42 increases during the inflation process. Thus, by combining the high speed / long stroke working state of the motor 1 with the increase in working fluid pressure, the cooling capacity per unit time is increased, thereby reducing the temperature of the expansion chamber to the preset temperature range in a short time, which can significantly shorten the cooling time and improve the cooling efficiency.

[0043] Preferably, in this embodiment, the working gas pressure P1 in the air intake container 100 is greater than the initial pressure of the back pressure chamber 42. Therefore, when the air intake valve assembly 10 is opened, the working gas in the air intake container 100 can automatically flow into the back pressure chamber 42 under the action of the pressure difference without the need for equipment such as a pump.

[0044] Example 2:

[0045] The only difference between this embodiment and Embodiment 1 is that the Stirling refrigerator further includes:

[0046] The outlet container 100' is used to store the working gas flowing out of the back pressure chamber 42; in this embodiment, the outlet container 100' can also be made of steel.

[0047] The outlet valve assembly 10' is connected to the outlet container 100' and the back pressure chamber 42 of the expander of the Stirling refrigerator, respectively;

[0048] When the temperature of the expansion chamber is within the preset temperature range (i.e., during the temperature control stage), the controller 8 controls the opening of the outlet valve assembly 10', allowing the working gas in the back pressure chamber 42 to enter the outlet container 100', thereby reducing the pressure inside the back pressure chamber 42. Simultaneously, when the motor 1 is a rotary motor, the controller 8 controls the motor 1 to rotate continuously at a second speed; when the motor 1 is a linear motor, the controller 8 controls the motor 1 to move continuously according to a second stroke. This process is the outlet process. Furthermore, the first speed is greater than the second speed, and the first stroke is greater than the second stroke.

[0049] Furthermore, during the aforementioned air discharge process, the pressure sensor 9 acquires the pressure change within the back pressure chamber 42 in real time. When the pressure within the back pressure chamber 42 decreases to the lower pressure threshold, the pressure sensor 9 feeds back the pressure within the back pressure chamber 42 to the controller 8. The controller 8 then closes the air discharge valve assembly 10' based on the pressure within the back pressure chamber 42 to end the air discharge process.

[0050] Since the temperature of the expansion chamber has been rapidly reduced to the preset temperature range by combining the high speed / long stroke working state of motor 1 with the increase of working fluid pressure in Embodiment 1, so as to achieve the purpose of rapid cooling, the pressure in the back pressure chamber 42 is further reduced by the above-mentioned air discharge process, and the speed or stroke of motor 1 is reduced at the same time, so that motor 1 can maintain the temperature of the expansion chamber in the low temperature range (i.e., the preset temperature range) under the conditions of lower speed / smaller stroke (i.e., second speed or second stroke), so as to reduce the mechanical load of motor 1 while ensuring the cooling effect.

[0051] Example 3:

[0052] This embodiment provides a refrigeration control method implemented using the Stirling refrigerator described in Embodiment 2, which includes the following steps:

[0053] S1. In the initial cooling stage (i.e., when the expansion chamber temperature is not within the preset temperature range), the controller 8 controls the motor 1 to work continuously in a first state. The continuous operation in the first state includes: when the motor 1 is a rotary motor, the motor 1 rotates continuously at a first speed; when the motor 1 is a linear motor, the motor 1 moves continuously according to a first stroke.

[0054] S2. During the continuous operation of motor 1 at the first speed or first stroke, the controller receives the expansion chamber temperature information of the Stirling refrigerator in real time, and controls the opening of the air intake valve assembly 10 according to the expansion chamber temperature, so that the working gas in the air intake container 100 enters the back pressure chamber 42 to increase the pressure in the back pressure chamber 42. This process is the inflation process.

[0055] S3. During the inflation process, the pressure change in the back pressure chamber 42 is obtained in real time by the pressure sensor 9. When the pressure in the back pressure chamber 42 increases to the upper pressure threshold, the pressure sensor 9 feeds back the pressure in the back pressure chamber 42 to the controller 8. The controller 8 closes the air intake valve assembly 10 according to the pressure in the back pressure chamber 42 to end the inflation process.

[0056] S4. Repeat steps S2-S3 until the temperature of the expansion chamber is within the preset temperature range. Then, the controller 8 controls the motor 1 to continue working in the second state to maintain the temperature of the expansion chamber within the preset temperature range. At the same time, the controller 8 controls the opening of the vent valve assembly 10', allowing the working gas in the back pressure chamber 42 to enter the vent container 100', thereby reducing the pressure in the back pressure chamber 42. This process is the venting process. The continuous operation in the second state includes: when the motor 1 is a rotary motor, the motor 1 rotates continuously at a second speed; when the motor 1 is a linear motor, the motor 1 moves continuously according to a second stroke, and the first speed is greater than the second speed, and the first stroke is greater than the second stroke.

[0057] In step S5, during the air discharge process, the pressure sensor 9 acquires the pressure change in the back pressure chamber 42 in real time. When the pressure in the back pressure chamber 42 drops to the lower pressure threshold, the pressure sensor 9 feeds back the pressure in the back pressure chamber 42 to the controller 8. The controller 8 closes the air discharge valve assembly 10' according to the pressure in the back pressure chamber 42 to end the air discharge process.

[0058] In summary, this invention combines working fluid pressure regulation with motor operating state control (i.e., speed control or stroke control) to achieve rapid cooling. Specifically, by increasing the working fluid pressure through a high-speed / long-stroke motor operating state, the cooling capacity per unit time is increased, thereby reducing the expansion chamber temperature to a preset temperature range in a short time. Furthermore, by reducing the working fluid pressure through a low-speed / short-stroke motor operating state, the expansion chamber temperature can be maintained within a low-temperature range under lower speed / shorter stroke conditions, thus ensuring the cooling effect while reducing the mechanical load on the motor.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A Stirling refrigerator with adjustable working fluid pressure, characterized in that, include: An inlet container, used to store the working gas; An intake valve assembly, which is connected to the intake container and the back pressure chamber of the expander of the Stirling refrigerator, respectively; And a controller, which is connected to the intake valve assembly and is used to receive expansion chamber temperature information from the Stirling refrigerator; When the temperature of the expansion chamber of the Stirling refrigerator is not within the preset temperature range, the controller controls the opening of the intake valve assembly so that the working gas in the intake container enters the back pressure chamber. While the working gas in the intake container enters the back pressure chamber, and when the motor of the Stirling refrigerator is a rotary motor, the controller controls the motor to rotate continuously at a first speed; when the motor of the Stirling refrigerator is a linear motor, the controller controls the motor to move continuously according to a first stroke. By increasing the working fluid pressure in combination with the high speed or long stroke of the motor, the cooling capacity per unit time is increased, and the temperature of the expansion chamber is reduced to the preset temperature range. Furthermore, by increasing the working fluid pressure in combination with the low speed or short stroke of the motor, the temperature of the expansion chamber is maintained within the low temperature range.

2. The Stirling refrigerator as described in claim 1, characterized in that, The Stirling refrigerator also includes: An outlet container, used to store the working gas flowing out of the back pressure chamber; An exhaust valve assembly is connected to the exhaust container and the back pressure chamber of the expander of the Stirling refrigerator, respectively, and is also connected to the controller; When the temperature of the expansion chamber is within the preset temperature range, the controller controls the opening of the outlet valve assembly, so that the working gas in the back pressure chamber enters the outlet container.

3. The Stirling refrigerator as described in claim 2, characterized in that, When the temperature of the expansion chamber is within the preset temperature range, and when the motor of the Stirling refrigerator is a rotary motor, the controller controls the motor to rotate continuously at a second speed. When the motor of the Stirling refrigerator is a linear motor, the controller controls the motor to move continuously according to a second stroke, so as to maintain the temperature of the expansion chamber within the preset temperature range.

4. The Stirling refrigerator as described in claim 3, characterized in that, The first rotational speed is greater than the second rotational speed, and the first stroke is greater than the second stroke.

5. The Stirling refrigerator as described in claim 2, characterized in that, The Stirling refrigerator also includes: A pressure sensor, which is mounted on the expander, is used to acquire pressure changes within the back pressure chamber.

6. The Stirling refrigerator as described in claim 5, characterized in that, When the pressure in the back pressure chamber increases to the upper pressure threshold, the intake valve assembly is closed, and / or when the pressure in the back pressure chamber decreases to the lower pressure threshold, the outlet valve assembly is closed.

7. A refrigeration control method based on the Stirling refrigerator according to any one of claims 1-6, characterized in that, Includes the following steps: When the expansion chamber temperature is not within the preset temperature range, the controller receives the expansion chamber temperature information and controls the opening of the intake valve assembly according to the expansion chamber temperature, so that the working gas in the intake container enters the back pressure chamber of the expander of the Stirling refrigerator. When the temperature of the expansion chamber is within the preset temperature range, the controller controls the opening of the outlet valve assembly, allowing the working gas in the back pressure chamber of the Stirling refrigerator's expander to enter the outlet container.

8. The refrigeration control method as described in claim 7, characterized in that, When the expansion chamber temperature is not within the preset temperature range, and when the motor of the Stirling refrigerator is a rotary motor, the controller controls the motor to rotate continuously at a first speed; when the motor of the Stirling refrigerator is a linear motor, the controller controls the motor to move continuously according to a first stroke. In addition, when the expansion chamber temperature is within the preset temperature range, and when the motor of the Stirling refrigerator is a rotary motor, the controller controls the motor to rotate continuously at a second speed; when the motor of the Stirling refrigerator is a linear motor, the controller controls the motor to move continuously according to a second stroke, so as to maintain the expansion chamber temperature within the preset temperature range. Furthermore, the first rotational speed is greater than the second rotational speed, and the first stroke is greater than the second stroke.

9. The refrigeration control method as described in claim 8, characterized in that, When the pressure in the back pressure chamber increases to the upper pressure threshold, the intake valve assembly is closed, and / or when the pressure in the back pressure chamber decreases to the lower pressure threshold, the exhaust valve assembly is closed.

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