A proportional valve for a ventilator

Abstract

The present invention discloses a proportional valve for a ventilator, which relates to the field of fluid control. The valve comprises a valve body, a valve core and a driving assembly, wherein the valve body is provided with an air inlet, an air outlet and a cavity connecting the air inlet and the air outlet, and is characterized in that the valve core has no direct contact with the valve body, an elastic sheet is provided between the outer wall of the valve core and the inner wall of the valve body, the elastic sheet divides the cavity into a first cavity and a second cavity which are not connected to each other, the second cavity is connected with the air inlet and the air outlet, the elastic sheet can hold the valve core against the inner wall of the valve body to cover the air inlet, the driving assembly can drive the valve core away from the inner wall of the valve body to connect the air inlet and the air outlet, and an air pipe connecting the air inlet and the first cavity is provided inside the valve core. The valve core in the proportional valve has no direct contact with the valve body, the friction generated by the proportional valve during operation is reduced, and the control of the gas flow is more precise and linear.

Description

Technical Field

[0001] The invention relates to the field of fluid control, and in particular to a proportional valve for a ventilator. Background Art

[0002] In modern clinical medicine, ventilators, as an effective means of artificially replacing spontaneous ventilation function, have been widely used in respiratory failure caused by various reasons, anesthesia respiratory management during major surgery, respiratory support therapy and emergency resuscitation, and occupy a very important position in the field of modern medicine.

[0003] During the use of the ventilator, the patient must be mechanically ventilated. The ventilator has its own compressor, turbine or other types of components to provide the gas source, so the ventilator needs a valve that can perform flow proportional control to control the gas flow. The key technical point of the proportional valve for the ventilator is to achieve precise control of a smaller flow range under a higher pressure. Summary of the invention

[0004] Existing typical proportional valves are as follows Figure 1 As shown. The valve core is fixed by the movable armature. Driven by the electromagnetic force of the coil, the valve core moves left and right along the sealing component that plays a guiding and sealing role to achieve the purpose of adjusting the size of the valve port. Since this proportional valve has relative movement with mutual contact, friction is inevitable. The influence of dynamic friction weakens the effect of electromagnetic force, especially when the input control current is small, it will seriously affect the proportional relationship between the input current and the output electromagnetic force. This is also one of the reasons for the instability of the small flow output of the existing proportional valve; and because the friction of the proportional valve is just opposite when it is opened and closed, the existing proportional valve has a large hysteresis when it is opened and closed. In order to minimize the influence of hysteresis on flow rate control, complex control algorithms have to be studied, which greatly increases the cost. At the same time, this component that uses a spring as a support for the valve core and the valve body to seal the air inlet also has the problems of spring aging failure and poor sealing.

[0005] Therefore, in the field of fluid control technology, it is urgent to propose a proportional valve that can reduce the influence of friction on flow in the proportional valve and realize precise control of gas flow. To this end, the present invention provides a proportional valve for a ventilator to solve the problem with the following technical points:

[0006] A proportional valve for a ventilator comprises a valve body, a valve core and a drive assembly, the valve body being provided with an air inlet, an air outlet and a cavity connecting the air inlet and the air outlet, and being characterized in that the valve core has no direct contact with the valve body, an elastic sheet is provided between the outer wall of the valve core and the inner wall of the valve body, the elastic sheet divides the cavity into a first cavity and a second cavity which are not connected to each other, the second cavity is connected to the air inlet and the air outlet, the elastic sheet can hold the valve core against the inner wall of the valve body to cover the air inlet, the drive assembly can drive the valve core away from the inner wall of the valve body to connect the air inlet and the air outlet, and an air pipe connecting the air inlet and the first cavity is provided inside the valve core.

[0007] As described above, the present invention provides a proportional valve including a valve body, a valve core, and a drive assembly. Compared with the prior art, the valve core in the proportional valve is independently arranged in the cavity of the valve body, and is connected to the valve body only by an elastic sheet. There is less contact between the valve core and the valve body, and the friction generated by the proportional valve during operation is greatly reduced. The drive assembly can drive the valve core away from the inner wall of the valve body. The greater the distance between the valve core and the inner wall of the valve body, the greater the gas flow rate, thereby achieving the effect of flow control. Since the influence of friction is reduced, the control of the valve core by the drive assembly is more precise and linear. The elastic force of the elastic sheet can restore the valve core to its original position, holding the valve core against the inner wall of the valve body to cover the air inlet. At the same time, the elastic sheet divides the cavity into a first cavity and a second cavity that are not connected to each other, and an air pipe connecting the first cavity and the air inlet is opened inside the valve core. When not working, the valve core presses against the inner wall of the valve body to seal the air inlet, and the gas in the air inlet enters the first cavity from the air pipe inside the valve core, forming back pressure, which presses the valve core tightly against the valve body, thereby enhancing the sealing effect of the air inlet and preventing poor sealing effect caused by failure of the sealing component.

[0008] Further technical solutions are:

[0009] The driving assembly includes an electromagnet and an armature, wherein the electromagnet is fixedly installed in the valve body, the armature is fixed at the rear end of the valve core, and the armature and the electromagnet are separated from each other. In this technical feature, the electromagnet generates suction with the armature under the action of electric current, pulls the valve core away from the valve seat, and the gas flows from the air inlet to the exhaust port. The greater the current, the greater the distance between the valve core and the valve seat, and the corresponding gas flow rate is also greater. The armature and the electromagnet are separated from each other to avoid friction caused by contact.

[0010] The valve core includes a sealing hemisphere, and the side wall of the air inlet of the valve core is a conical surface that matches the sealing hemisphere, and the conical surface and the sealing hemisphere cooperate to form a ball head conical surface sealing structure. In existing proportional valves, the valve body is often provided with a rubber pad for sealing, but since the size, hardness, rigidity, etc. of the rubber pad cannot be kept consistent, the large deformation produced by the rubber pad will affect the accuracy of flow control. Therefore, in the present invention, the ball head conical surface sealing structure formed by the conical air inlet side wall and the sealing hemisphere is used as the sealing structure of the proportional valve. A hard seal is formed between the sealing hemisphere and the air inlet, and both are metal parts, and the deformation is very small and can be almost ignored, which can ensure the linear control of the flow by the proportional valve.

[0011] The valve core also includes a connecting column, the front end of which is used to assemble a sealing hemisphere, a first slot for installing an elastic sheet is formed between the connecting column and the sealing hemisphere, and the rear end of the connecting column is used to install a fixed armature, and the sealing hemisphere is made of stainless steel or ceramic. In this technical feature, the combined valve core is conducive to the installation and replacement of the elastic sheet. The sealing hemisphere is made of stainless steel or ceramic, which can make it have a higher hardness.

[0012] The valve body includes a valve body and a valve seat, the valve body and the valve seat are assembled to form a second slot for installing an elastic sheet, the valve seat and the elastic sheet are enclosed to form a second cavity, and the material of the valve seat is copper alloy or aluminum alloy. In this technical feature, the valve seat and the valve body are assembled to form a valve body, which facilitates the installation of the valve core and the elastic sheet inside the valve body. Copper alloy or aluminum alloy is used as the valve seat material, which is conducive to the precision processing and manufacturing of the valve seat.

[0013] The elastic sheet is a combination of a reed and a diaphragm, the reed and the diaphragm are stacked, the diaphragm forms the boundary of the first cavity, and the reed forms the boundary of the second cavity. Since the gas will enter the first cavity from the air inlet through the organs inside the valve core to form a back pressure for strengthening the sealing effect, the reed supports the diaphragm to prevent the diaphragm from being damaged due to excessive pressure and reduce the deformation of the diaphragm. The elastic restoring force of the reed and the diaphragm together generate pre-pressure on the valve core.

[0014] The spring material is 3J21 stainless steel spring material.

[0015] The diaphragm material is nylon fiber reinforced rubber.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The structure of the present invention is scientific and reasonable, and it is safe and convenient to use. The present invention provides a proportional valve including a valve body, a valve core, and a drive assembly. Compared with the prior art, the valve core in the proportional valve is independently arranged in the cavity of the valve body, and is connected to the valve body only by an elastic sheet. There is less contact between the valve core and the valve body, and the friction generated by the proportional valve during operation is greatly reduced, and the control of the flow rate is more precise and linear. The elastic force of the elastic sheet can restore the valve core to its original position, holding the valve core against the inner wall of the valve body to cover the air inlet. The proportional valve also adopts a ball head cone surface hard sealing structure formed by a sealing hemisphere and a conical surface, which can improve the sealing effect and reduce the control error. The combination of the metal reed and the rubber diaphragm can improve the reliability of the elastic sheet. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0019] Figure 1 It is a schematic diagram of an existing proportional valve;

[0020] Figure 2 It is a schematic diagram of the structure of the present invention;

[0021] In the figure: 1. electromagnet; 2. armature; 3. connecting column; 4. diaphragm; 5. reed; 6. sealing hemisphere; 7. valve body; 8. valve seat. DETAILED DESCRIPTION

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0023] Please refer to the accompanying drawings, the present invention provides a technical solution:

[0024] A proportional valve for a ventilator comprises a valve body, a valve core and a drive assembly, the valve body being provided with an air inlet, an air outlet and a cavity connecting the air inlet and the air outlet, and being characterized in that the valve core has no direct contact with the valve body, an elastic sheet is provided between the outer wall of the valve core and the inner wall of the valve body, the elastic sheet divides the cavity into a first cavity and a second cavity which are not connected to each other, the second cavity is connected to the air inlet and the air outlet, the elastic sheet can hold the valve core against the inner wall of the valve body to cover the air inlet, the drive assembly can drive the valve core away from the inner wall of the valve body to connect the air inlet and the air outlet, and an air pipe connecting the air inlet and the first cavity is provided inside the valve core.

[0025] As described above, the present invention provides a proportional valve including a valve body, a valve core, and a drive assembly. Compared with the prior art, the valve core in the proportional valve is independently arranged in the cavity of the valve body, and is connected to the valve body only by an elastic sheet. There is less contact between the valve core and the valve body, and the friction generated by the proportional valve during operation is greatly reduced. The drive assembly can drive the valve core away from the inner wall of the valve body. The greater the distance between the valve core and the inner wall of the valve body, the greater the gas flow rate, thereby achieving the effect of flow control. Since the influence of friction is reduced, the control of the valve core by the drive assembly is more precise and linear. The elastic force of the elastic sheet can restore the valve core to its original position, holding the valve core against the inner wall of the valve body to cover the air inlet. At the same time, the elastic sheet divides the cavity into a first cavity and a second cavity that are not connected to each other, and an air pipe connecting the first cavity and the air inlet is opened inside the valve core. When not working, the valve core presses against the inner wall of the valve body to seal the air inlet, and the gas in the air inlet enters the first cavity from the air pipe inside the valve core, forming back pressure, which presses the valve core tightly against the valve body, thereby enhancing the sealing effect of the air inlet and preventing poor sealing effect caused by failure of the sealing component.

[0026] Further technical solutions are:

[0027] The driving assembly includes an electromagnet 1 and an armature 2, wherein the electromagnet 1 is fixedly installed in the valve body, the armature 2 is fixed at the rear end of the valve core, and the armature 2 and the electromagnet 1 are separated from each other. In this technical feature, the electromagnet 1 generates suction with the armature 2 under the action of the current, pulling the valve core away from the valve seat 8, and the gas flows from the air inlet to the exhaust port. The greater the current, the greater the distance between the valve core and the valve seat 8, and the corresponding gas flow rate is also greater. The armature 2 and the electromagnet 1 are separated from each other to avoid friction caused by contact.

[0028] The valve core includes a sealing hemisphere 6, and the side wall of the air inlet of the valve core is a conical surface that matches the sealing hemisphere 6. The conical surface and the sealing hemisphere 6 cooperate to form a ball head conical surface sealing structure. In existing proportional valves, the valve body is often provided with a rubber pad for sealing. However, since the size, hardness, rigidity, etc. of the rubber pad cannot be kept consistent, the large deformation produced by the rubber pad will affect the accuracy of flow control. Therefore, in the present invention, the ball head conical surface sealing structure formed by the conical air inlet side wall and the sealing hemisphere 6 is used as the sealing structure of the proportional valve. A hard seal is formed between the sealing hemisphere 6 and the air inlet. Both are metal parts, and the deformation is very small and can be almost ignored, which can ensure the linear control of the proportional valve on the flow.

[0029] The valve core also includes a connecting column 3, the front end of which is used to assemble a sealing hemisphere 6, a first slot for installing an elastic sheet is formed between the connecting column 3 and the sealing hemisphere 6, and the rear end of the connecting column 3 is used to install and fix the armature 2, and the sealing hemisphere 6 is made of stainless steel or ceramic. In this technical feature, the combined valve core is conducive to the installation and replacement of the elastic sheet. The sealing hemisphere 6 is made of stainless steel or ceramic, which can make it have a higher hardness.

[0030] The valve body includes a valve body 7 and a valve seat 8, wherein the valve body 7 and the valve seat 8 are assembled to form a second slot for installing an elastic sheet, and the valve seat 8 and the elastic sheet are enclosed to form a second cavity, and the material of the valve seat 8 is copper alloy or aluminum alloy. In this technical feature, the valve seat 8 and the valve body 7 are assembled to form a valve body, which facilitates the installation of the valve core and the elastic sheet inside the valve body. Copper alloy or aluminum alloy is used as the material of the valve seat 8, which is conducive to the precision processing and manufacturing of the valve seat 8.

[0031] The elastic sheet is a combination of a reed 5 and a diaphragm 4, the reed 5 and the diaphragm 4 are stacked, the diaphragm 4 forms the boundary of the first cavity, and the reed 5 forms the boundary of the second cavity. Since the gas will enter the first cavity from the air inlet through the organs inside the valve core to form a back pressure for strengthening the sealing effect, the reed 5 supports the diaphragm 4 to prevent the diaphragm 4 from being damaged due to excessive pressure and reduce the deformation of the diaphragm 4. The elastic restoring force of the reed 5 and the diaphragm 4 together generate pre-pressure on the valve core.

[0032] The material of the reed 5 is 3J21 stainless steel spring material.

[0033] The material of the diaphragm 4 is nylon fiber reinforced rubber.

[0034] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A proportional valve for a ventilator, comprising a valve body, a valve core and a drive assembly, wherein the valve body is provided with an air inlet, an air outlet and a cavity connecting the air inlet and the air outlet, It is characterized in that The valve core has no direct contact with the valve body, an elastic sheet is provided between the outer wall of the valve core and the inner wall of the valve body, the elastic sheet divides the cavity into a first cavity and a second cavity which are not connected to each other, the second cavity is connected to the air inlet and the air outlet, the elastic sheet can hold the valve core against the inner wall of the valve body to cover the air inlet, the driving assembly can drive the valve core away from the inner wall of the valve body to connect the air inlet and the air outlet, and an air pipe connecting the air inlet and the first cavity is opened inside the valve core; The driving assembly comprises an electromagnet (1) and an armature (2), wherein the electromagnet (1) is fixedly mounted in the valve body, the armature (2) is fixed to the rear end of the valve core, and the armature (2) and the electromagnet (1) are separated from each other; The elastic sheet is a combination of a reed sheet (5) and a diaphragm sheet (4); the reed sheet (5) and the diaphragm sheet (4) are stacked and arranged; the diaphragm sheet (4) forms a first cavity boundary, and the reed sheet (5) forms a second cavity boundary.

2. A proportional valve for a ventilator according to claim 1, It is characterized in that The valve core comprises a sealing hemisphere (6); the side wall of the valve core air inlet is a conical surface that matches the sealing hemisphere (6); the conical surface and the sealing hemisphere (6) cooperate to form a ball head conical surface sealing structure.

3. A proportional valve for a ventilator according to claim 2, It is characterized in that The valve core also includes a connecting column (3), the front end of the connecting column (3) is used to assemble the sealing hemisphere (6), a first slot for installing an elastic sheet is formed between the connecting column (3) and the sealing hemisphere (6), and the rear end of the connecting column (3) is used to install the fixed armature (2), and the sealing hemisphere (6) is made of stainless steel or ceramic.

4. A proportional valve for a ventilator according to claim 2, It is characterized in that The valve body comprises a valve body (7) and a valve seat (8), wherein the valve body (7) and the valve seat (8) are assembled to form a second slot for installing an elastic sheet, and the valve seat (8) and the elastic sheet are combined to form a second cavity, and the material of the valve seat (8) is a copper alloy or an aluminum alloy.

5. A proportional valve for a ventilator according to claim 1, It is characterized in that The material of the spring leaf (5) is 3J21 stainless steel spring material.

6. A proportional valve for a ventilator according to claim 1, It is characterized in that The material of the diaphragm (4) is nylon fiber reinforced rubber.

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