Discharge valve

Abstract

This invention relates to a discharge valve. The discharge valve is disposed in a recirculation line through which gas discharged from a fuel cell stack is recirculated back to the fuel cell stack. The discharge valve opens or closes the discharge line, allowing fluid to be discharged. The discharge valve includes a valve body connected to the discharge line; the drive unit is disposed within the valve body and is capable of vertical movement. A diaphragm is connected to the lower end of the drive unit and selectively opens or closes the discharge line based on vertical movement. The drive unit switches between a closed state, a first open state, and a second open state, in which the discharge line is closed by the diaphragm; in the first open state, the discharge line is opened to a first degree of openness; and in the second open state, the discharge line is opened to a second degree of openness greater than the first degree of openness.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2019-0168235, filed on December 16, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a discharge valve, and more specifically, to a discharge valve configured to release overpressure without the need for a separate pressure reducing valve. Background Technology

[0004] A fuel cell system is a system that generates electricity through a chemical reaction between hydrogen supplied to the fuel cell stack and oxygen from the air. Fuel cell systems are used in the field of hydrogen-powered vehicles (hydrogen fuel cell vehicles). Figure 1 An example of a fuel cell system 10 based on related technologies is shown. (Reference) Figure 1 The fuel cell system 10 includes a fuel cell stack 20, a compressor (not shown), and a hydrogen supply unit 30. The compressor (not shown) is configured to compress air and supply the compressed air to the fuel cell stack 20; the hydrogen supply unit 30 is configured to supply hydrogen to the fuel cell stack 20. The air compressed by the compressor can be supplied to the cathode 21 of the fuel cell stack 20, and the hydrogen stored in the hydrogen supply unit 30 can be supplied to the anode 23 of the fuel cell stack 20 via a hydrogen supply line. A hydrogen supply valve 31 and an injector 32 can be disposed in the hydrogen supply line.

[0005] The gas (hydrogen) discharged from the fuel cell stack 20 is recirculated to the fuel cell stack in the recirculation line 41. In the recirculation line 41, a dehydrator 60 is provided to remove condensate contained in the recirculated gas hydrogen, a drain valve 61 is provided to discharge condensate from the dehydrator, an exhaust valve 70 is provided to discharge gas if necessary, and a pressure reducing valve 50 is provided to release overpressure in the recirculation line 41.

[0006] In the related technologies described above, the fuel cell system has a mechanical pressure reducing valve 50 that is separate from the exhaust valve 70 or the drain valve 61 to release overpressure in the system. However, the configuration with a separate pressure reducing valve 50 increases cost and structural complexity.

[0007] Therefore, an integrated valve is needed, which integrates the function of a pressure reducing valve into a valve 70 for discharging gas from the system or a valve 61 for discharging condensate, thereby enabling the proper performance of the following processes: discharging a small amount of gas during normal operation and discharging a large amount of gas under overpressure conditions. Summary of the Invention

[0008] The present invention provides a discharge valve configured as a single valve and operating like valves and pressure reducing valves in the related art, which discharge gas to improve fuel utilization and regulate hydrogen concentration in a fuel cell system; the pressure reducing valve discharges gas to release overpressure under overpressure conditions.

[0009] An exemplary embodiment of the present invention provides a discharge valve disposed in a recirculation line through which gas discharged from a fuel cell stack is recirculated back to the fuel cell stack. The discharge valve is configured to open or close the discharge line through which fluid in the recirculation line is discharged. The discharge valve may include a valve body, a drive unit, and a diaphragm. The valve body is connected to the discharge line. The drive unit is disposed in the valve body and is capable of vertical movement. The diaphragm is connected to the lower end of the drive unit and configured to selectively open or close the discharge line based on the vertical movement of the drive unit. The drive unit is configured to switch between a closed state, a first open state, and a second open state. In the closed state, the discharge line is closed by the diaphragm. In the first open state, the discharge line is opened to a first degree of opening. In the second open state, the discharge line is opened to a second degree of opening greater than the first degree of opening.

[0010] Another exemplary embodiment of the present invention provides a discharge valve configured to open or close a discharge line through which fluid is discharged. The discharge valve may include: a valve body, a drive unit, and a diaphragm. The valve body is connected to the discharge line. The drive unit is disposed in the valve body and is capable of vertical movement. The diaphragm is connected to the lower end of the drive unit and configured to selectively open or close the discharge line based on the vertical movement of the drive unit. The drive unit is configured to switch between a closed state, a first open state, and a second open state. In the closed state, the discharge line is closed by the diaphragm. In the first open state, the discharge line is opened to a first degree of opening. In the second open state, the discharge line is opened to a second degree of opening greater than the first degree of opening. Attached Figure Description

[0011] The object, features, and advantages of the invention will become clearer from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0012] Figure 1 This is a schematic diagram showing an example of a fuel cell system according to the related technology of the present invention.

[0013] Figure 2 This is a schematic diagram showing the closed state of the discharge valve in the related technology.

[0014] Figure 3 This is a schematic diagram showing the open state of the discharge valve in the related technology.

[0015] Figure 4 This is a schematic diagram showing the closed state of the discharge valve according to the present invention.

[0016] Figure 5 This is a schematic diagram showing the first open state of the discharge valve according to the present invention.

[0017] Figure 6 This is a schematic diagram showing the second open state of the discharge valve according to the present invention.

[0018] Labels for each component in the diagram:

[0019] 10: Fuel Cell System

[0020] 20: Fuel Cell Stack

[0021] 21: Cathode

[0022] 23: Anode

[0023] 30: Hydrogen supply unit

[0024] 31: Hydrogen supply valve

[0025] 32: Injector

[0026] 41: Recirculation line

[0027] 42: Discharge pipeline

[0028] 43: Entrance

[0029] 44: Discharge outlet

[0030] 50: Pressure reducing valve

[0031] 60: Dehydrator

[0032] 61: Drain valve

[0033] 70: Exhaust valve

[0034] 71: Shell

[0035] 72: Coil

[0036] 73: Core

[0037] 74: Plunger

[0038] 75: Spring

[0039] 76: Diaphragm

[0040] 100: Discharge valve

[0041] 200: Valve body unit

[0042] 210: Shell

[0043] 220: Coil

[0044] 230: Sleeve

[0045] 231: Protrusion

[0046] 233: Cover

[0047] 300: Drive Unit

[0048] 310: Plunger component

[0049] 311: Supporting protrusion

[0050] 312: Stepped section

[0051] 320: Core component

[0052] 321: Stepped protrusion

[0053] 500: Diaphragm

[0054] 610: First elastic member

[0055] 620: Second elastic member. Detailed Implementation

[0056] It should be understood that the term "vehicle" or "of a vehicle" or other similar terms as used herein generally include motor vehicles, such as passenger cars including sport utility vehicles (SUVs), buses, trucks, and various commercial vehicles, vessels including various boats and ships, aircraft, etc., and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., vehicles derived from non-fossil fuels). As mentioned herein, a hybrid vehicle is a vehicle with two or more power sources, such as a vehicle powered by both gasoline and electricity.

[0057] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a,” “an,” and “described” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of the stated features, values, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, values, steps, operations, elements, components, and / or groups thereof. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0058] While the exemplary embodiments are described as using multiple units to perform the exemplary processes, it should be understood that the exemplary processes may also be performed by one or more modules. Furthermore, it should be understood that the term controller / control unit refers to a hardware device including a memory and a processor, and that the hardware device is specifically programmed to perform the processes described herein. The memory is configured to store modules, and the processor is specifically configured to execute said modules to complete one or more processes, which will be further described below.

[0059] Unless otherwise stated or obvious from the context, as used herein, the term “about” is understood to mean within the normal tolerance range in the field, such as within 2 standard deviations of the mean. “About” can be understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the specified value. All numerical values ​​provided herein are modified by the term “about” unless the context clearly indicates otherwise.

[0060] In the following, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0061] First, the exemplary embodiments described below are exemplary embodiments suitable for understanding the technical features of the discharge valve according to the present invention. However, the present invention is not limited to the exemplary embodiments described below, and the technical features of the present invention are not limited to the exemplary embodiments described herein, and various modifications can be made within the technical scope of the present invention.

[0062] The exhaust valve 70 may include a housing 71, a core 73, and a coil 72, wherein the core 73 is disposed within the housing 71, and the coil 72 is disposed between the core 73 and the housing 71. Additionally, the exhaust valve 70 may include a plunger 74, a spring 75, and a diaphragm 76, wherein the plunger 74 is disposed within the housing 71 and is movable by an applied force; the spring 75 is configured to elastically press the plunger 74 downwards; and the diaphragm 76 is connected to the lower end of the plunger 74 and configured to open or close the exhaust line 42. The exhaust line 42 may include an inlet 43 and an outlet 44, through which gas flows toward the exhaust valve 70; and the outlet 44 is configured to discharge gas to the outside by communicating with the inlet 43 when the exhaust valve 70 is open.

[0063] refer to Figure 2 In the closed state, spring 75 can press plunger 74 towards inlet 43, thereby blocking inlet 43 with diaphragm 76 to prevent gas from escaping. (Reference) Figure 3When force is applied, the plunger 74 and diaphragm 76 move upward by overcoming the elastic force of the spring 75, thereby opening the discharge line 42. In particular, the inlet 43 and the outlet 44 are connected to each other, allowing gas to flow to the outside.

[0064] In the case of the exhaust valve 70 in the relevant technology, the flow rate of the discharged gas is constant, such as... Figure 2 and Figure 3 As shown. A high-flow-rate exhaust valve 70 is advantageous for releasing overpressure in the recirculation line 41, but during normal operation, it may worsen fuel utilization or make it difficult to control the hydrogen concentration in the fuel cell system 10. Conversely, a low-flow-rate exhaust valve 70 has the problem of making it difficult to quickly release overpressure occurring in the recirculation line 41.

[0065] Therefore, the present invention provides an improved discharge valve that integrates a pressure-reducing function into a valve in the related art, enabling the discharge valve to discharge gas at a low flow rate under normal operating conditions of the fuel cell system 10, and to discharge gas at a high flow rate when overpressure occurs in the recirculation line 41. The discharge valve 100 according to the present invention will be described below.

[0066] The discharge valve 100 according to the invention can be configured to open or close the discharge line 42 through which fluid is discharged. For example, when the discharge valve 100 is used in a fuel cell system, the discharge valve 100 can be located in the recirculation line 41 (see...). Figure 1 In this configuration, gas discharged from the fuel cell stack is recirculated back to the fuel cell stack via the recirculation line 41, and the discharge valve 100 can be configured to open or close the discharge line 42, through which fluid in the recirculation line 41 is discharged. Specifically, the discharge line 42 may include an inlet 43 and an outlet 44, through which gas flows toward the discharge valve 100; the outlet 44 is configured to discharge gas to the outside by communicating with the inlet 43 when the discharge valve 100 is open.

[0067] refer to Figures 4 to 6The discharge valve 100 according to the present invention may include a valve body 200, a drive unit 300, and a diaphragm 500. The valve body 200 may be connected to a discharge line 42. The drive unit 300 may be arranged in the valve body 200 to be vertically movable (e.g., upward and downward). The diaphragm 500 may be coupled to the lower end of the drive unit 300 and configured to selectively open or close the discharge line 42 based on the vertical movement of the drive unit 300. Specifically, the vertical direction is defined based on the drawings; the upward direction refers to the direction in which the drive unit 300 moves to open the discharge line 42, while the downward direction refers to the direction in which the diaphragm 500 presses the inlet 43 in the discharge line 42 to close the discharge line 42.

[0068] Drive unit 300 is set to the off state (see Figure 4 ), first open state (see Figure 5 ) and the second open state (see Figure 6 Switch between the off state and the off state (see Figure 4 Under the first open state (see...), the discharge line 42 is closed by the diaphragm 500; in the first open state (see...), Figure 5 Under the condition that the discharge pipeline 42 is opened to the first opening degree; in the second opening state (see... Figure 6 In the first open state, the lower end of the diaphragm 500 can be moved upward by a predetermined distance X1 by the movement of the drive unit 300 to open the discharge line 42 to the first open state. In the second open state, the lower end of the diaphragm 500 can be moved upward by a predetermined distance X1+X2 by the movement of the drive unit 300 to open the discharge line 42 to the second open state, which is greater than the first open state.

[0069] As described above, the discharge valve 100 according to the present invention can regulate the flow rate of gas discharged through the discharge line 42 by utilizing the opening degree of a multi-stage regulating valve. Specifically, when the discharge valve 100 according to the present invention is applied to a fuel cell system, during normal system operation, if it is necessary to improve fuel utilization and ensure an appropriate hydrogen concentration, the discharge valve 100 can be opened to a first open state to discharge gas at a low flow rate. Additionally, when overpressure occurs in the recirculation line 41, the discharge valve 100 can be opened to a second open state to rapidly release the overpressure.

[0070] Therefore, the discharge valve 100 according to the invention, configured as a single valve, can operate both like a valve in the related art and like a pressure reducing valve, which discharges gas to improve fuel utilization and control hydrogen concentration in the fuel cell system; the pressure reducing valve discharges gas to release overpressure under overpressure conditions. When force is applied, the drive unit 300 can switch from a closed state to a first open state, and when the fluid pressure is equal to or greater than a reference pressure, the drive unit 300 can switch from the first open state to a second open state by the fluid pressure in the recirculation line 41.

[0071] Specifically, when overpressure occurs in the system, the fluid pressure in the recirculation line 41 can be equal to or greater than the reference pressure. When it is necessary to vent gas to improve fuel utilization during system operation, the vent valve 100 can be opened to a first open state by an applied force to vent gas at a low flow rate. Furthermore, when overpressure occurs in the system, the drive unit 300 and the diaphragm 500 can be moved by the pressure of the gas flowing to the inlet 43 of the vent line 42 to open the vent valve 100 to a second open state to vent gas at a high flow rate.

[0072] Specifically, the drive unit 300 may include a plunger 310 and a core 320. The plunger 310 may be arranged in the valve body 200 to be movable upward and downward. The plunger 310 may be arranged above the diaphragm 500. Additionally, the core 320 may be arranged in the valve body 200 to be movable upward and downward. The core 320 may be arranged above the plunger 310. Particularly, in the closed state, the core 320 may be arranged above the plunger 310 and spaced apart from the plunger 310.

[0073] Meanwhile, the discharge valve 100 according to the present invention may further include a first elastic portion 610 and a second elastic portion 620. The first elastic portion 610 elastically presses the plunger 310 downward. When the plunger 310 moves upward by an applied force, the first elastic portion 610 can be compressed. The second elastic portion 620 elastically presses the core 320 downward. When the fluid pressure is equal to or greater than the reference pressure, the second elastic portion 620 can be compressed and moved upward by the fluid pressure in the circulation line 41 causing the plunger 310 to move upward and thus compressing the core 320.

[0074] In other words, when the fluid pressure in the recirculation line 41 is equal to or greater than the reference pressure, the diaphragm 500 and plunger 310 can move upwards due to the fluid pressure, and the plunger 310 can press the core 320 with a pressing force that overcomes the elasticity of the second elastic part 620, thereby moving the core 320. Therefore, the degree of opening in the second open state can be increased compared to the first open state where only the plunger 310 moves. When the fluid pressure is less than the reference pressure, the second elastic part 620 will not be compressed even if force is applied, so the plunger 310 can move to the lower end of the core 320.

[0075] The valve body 200 may include a sleeve 230 and a housing 210, the sleeve 230 being configured to receive the drive portion 300; the housing 210 being disposed outside the sleeve 230 to place the coil 220 between the sleeve 230 and the housing 210. The sleeve 230 may include a protrusion 231 that protrudes from the inner surface of the sleeve 230 and is configured to support the lower end of the core 320. Additionally, the sleeve 230 may further include a cover 233 disposed at the upper end of the sleeve 230.

[0076] Furthermore, the upper end of the first elastic portion 610 can be supported by the protrusion 231, while the lower end of the first elastic portion 610 can be supported by a stepped support protrusion 311 formed on the plunger 310. Therefore, when no force is applied, the first elastic portion 610 can press the plunger 310 downward. The stepped portion 312 can be formed on the outer surface of the plunger 310, and when the plunger 310 presses against the core 320 in the second open state, it can limit the upward movement distance of the plunger 310.

[0077] The upper end of the second elastic portion 620 can be supported by the cover portion 233, while the lower end of the second elastic portion 620 can be supported by the stepped protrusion 321 formed on the core portion 320. Therefore, when no overpressure occurs (e.g., the fluid pressure is less than the reference pressure), the second elastic portion 620 can press down on the core portion 320.

[0078] When the plunger 310 of the drive unit 300 is compressed downwards and moved to its lowest position by the first elastic part 610, the discharge valve can be in the closed state. Specifically, the discharge line 42 can be closed by the diaphragm 500 to prevent gas (fluid) from flowing to the outside. When the plunger 310 moves upwards by an applied force, and then the upward movement of the plunger 310 is restricted by the core 320 supported by the second elastic part 620, the discharge valve can be in the first open state. Specifically, the discharge line 42 can be opened to the first open degree, thereby discharging fluid to the outside at a low flow rate.

[0079] Furthermore, when fluid pressure causes the plunger 310 to move upward, compressing the core 320 and moving it to its uppermost position, the discharge valve can be in a second open state. Specifically, the discharge line 42 can be opened to the second open degree, thereby discharging fluid to the outside at a high flow rate. This releases overpressure in the recirculation line 41. Subsequently, when the fluid pressure is lower than the reference pressure, the plunger 310 and core 320 can move downward, allowing the discharge valve to be in a first open or closed state.

[0080] As described above, the discharge valve according to the present invention can regulate the flow rate of gas discharged through the discharge line by utilizing the opening degree of a multi-stage regulating valve. For example, when the discharge valve is applied to a fuel cell system, during normal system operation, if it is necessary to improve fuel utilization and ensure an appropriate hydrogen concentration, the discharge valve can be opened to a first open state to discharge gas at a low flow rate. Additionally, when overpressure occurs in the recirculation line, the discharge valve can be opened to a second open state to rapidly release the overpressure.

[0081] Therefore, the discharge valve according to the invention, configured as a single valve, can operate both like a valve in the related art and like a pressure reducing valve, which discharges gas to improve fuel utilization and control hydrogen concentration in the fuel cell system; the pressure reducing valve discharges gas to release overpressure under overpressure conditions.

[0082] Although specific exemplary embodiments of the present invention have been described above, the spirit and scope of the present invention are not limited to the specific exemplary embodiments, and those skilled in the art can make various modifications and changes to the present invention without departing from the subject matter of the invention disclosed in the claims.

[0083] The discharge valve according to the present invention can regulate the flow rate of gas discharged through the discharge line by utilizing the opening degree of a multi-stage regulating valve. For example, when the discharge valve is applied to a fuel cell system, during normal system operation, if it is necessary to improve fuel utilization and ensure an appropriate hydrogen concentration, the discharge valve can be opened to a first open state to discharge gas at a low flow rate. Additionally, when overpressure occurs in the recirculation line, the discharge valve can be opened to a second open state to rapidly release the overpressure.

[0084] Therefore, the discharge valve according to the invention, configured as a single valve, can operate both like a valve in the related art and like a pressure reducing valve, which discharges gas to improve fuel utilization and control hydrogen concentration in the fuel cell system; the pressure reducing valve discharges gas to release overpressure under overpressure conditions, thereby reducing costs and simplifying the configuration of the fuel cell system.

Claims

1. An exhaust valve provided in a recirculation line through which a gas exhausted from a fuel cell stack is recirculated to the fuel cell stack, the exhaust valve configured to open or close an exhaust line through which a fluid in the recirculation line is exhausted, the exhaust valve comprising: a valve body connected to the exhaust line; a driving portion arranged in the valve body to be vertically movable; and a diaphragm coupled to a lower end of the driving portion and configured to selectively open or close the exhaust line based on vertical movement of the driving portion; wherein the driving portion is provided to be switched between a closed state in which the exhaust line is closed by the diaphragm, a first open state in which the exhaust line is opened to a first open degree, and a second open state in which the exhaust line is opened to a second open degree greater than the first open degree, wherein the driving portion comprises: a plunger provided in the valve body to be vertically movable and arranged above the diaphragm; and a core provided in the valve body to be vertically movable and arranged above the plunger, wherein the valve body comprises: a sleeve configured to accommodate the driving portion; and a housing arranged outside the sleeve to interpose a coil between the sleeve and the housing, wherein the sleeve comprises a protrusion protruding from an inner surface of the sleeve and configured to support a lower end of the core.

2. The discharge valve of claim 1, wherein, The driving portion is switched from the closed state to the first open state by an applied force, and when a fluid pressure is equal to or greater than a reference pressure, the driving portion is switched from the first open state to the second open state by the fluid pressure in the recirculation line.

3. The exhaust valve of claim 1, further comprising: a first elastic portion configured to elastically press the plunger downward, and configured to be compressed when the plunger is moved upward by the applied force; and a second elastic portion configured to elastically press the core downward, and configured to be compressed when the plunger is moved upward by the fluid pressure in the recirculation line such that the core is moved upward while being compressed.

4. The discharge valve of claim 3, wherein, In the closed state, the core is arranged above the plunger and spaced apart from the plunger, When the plunger of the driving portion is moved to a lowermost side by being compressed downward by the first elastic portion, the exhaust valve is in the closed state; When the plunger is moved upward by the applied force and then the upward movement of the plunger is limited by the core supported by the second elastic portion, the exhaust valve is in the first open state; When the plunger is moved upward by the fluid pressure such that the core is moved to an uppermost side while being compressed, the exhaust valve is in the second open state.

5. The discharge valve of claim 4, wherein, An upper end of the first elastic portion is supported by the protrusion, and a lower end of the first elastic portion is supported by a stepped support protrusion formed on the plunger.

6. The discharge valve of claim 5, wherein, The sleeve further includes a cap portion provided at an upper end of the sleeve, an upper end of the second elastic portion is supported by the cap portion, and a lower end of the second elastic portion is supported by a stepped protrusion forming a step on the core portion.

7. A drain valve configured to open or close a drain line through which fluid is drained, the drain valve comprising: a valve body connected to the drain line; a drive portion arranged in the valve body to be vertically movable; and a diaphragm coupled to a lower end of the drive portion and configured to selectively open or close the drain line based on vertical movement of the drive portion; wherein the drive portion is provided to switch between a closed state in which the drain line is closed by the diaphragm, a first open state in which the drain line is opened to a first open degree, and a second open state in which the drain line is opened to a second open degree greater than the first open degree, wherein the drive portion includes: a plunger provided in the valve body to be vertically movable and arranged above the diaphragm; and a core provided in the valve body to be vertically movable and arranged above the plunger, wherein the valve body includes: a sleeve configured to accommodate the drive portion; and a housing arranged outside the sleeve to interpose a coil between the sleeve and the housing, wherein the sleeve includes a protruding portion protruding from an inner surface of the sleeve and configured to support a lower end of the core.

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