Fuel shutoff valve

Abstract

The present invention relates to a valve installed in a valve body including a supply channel, a discharge channel, and a valve seat formed between the supply channel and the discharge channel, which controls the flow of fuel by opening and closing the valve seat. Considering its configuration, it includes a housing with a connector integrally formed for power and signal transmission, a coil assembly provided inside the housing and electrically connected to the connector, a core coupled so as to penetrate the coil assembly and having a first operating groove formed therein, a plunger movably installed in the first operating groove and having a second operating groove connected to the supply channel, a friction member interposed between the core and the plunger to reduce friction, a pilot movably installed in the second operating groove and having a pilot orifice connecting the second operating groove and the discharge channel, and a spring interposed between the core and the plunger to elastically support the plunger so that the pilot is in close contact with the valve seat.

Description

Technical Field

[0001] The present invention relates to a fuel shut-off valve, and more particularly to a fuel shut-off valve with improved openness, airtightness, and noise performance.

Background Art

[0002] Generally, a fuel cell system is a system that produces electrical energy by reacting hydrogen and oxygen. Research and development of these fuel cell systems have been continuously carried out as an alternative to solve environmental problems.

[0003] A fuel cell electric vehicle (FCEV) is a vehicle in which a fuel cell is applied instead of an internal combustion engine, and is configured such that a motor is driven to run by electrical energy generated by the reaction of hydrogen and oxygen.

[0004] The above-described fuel cell vehicle includes a stack that generates electrical energy, a fuel supply system that supplies hydrogen as fuel, an air supply system that supplies oxygen as an oxidant required for an electrochemical reaction, and a system that manages heat and water generated in the stack.

[0005] Among the above-described systems, the fuel supply system is provided with a hydrogen tank in which high-pressure hydrogen is stored, and the hydrogen stored in the hydrogen tank is depressurized to a predetermined pressure and supplied to the stack.

[0006] In Korean Registered Patent Publication No. 10-1893361 (September 4, 2018), a fuel shut-off valve is disclosed that is installed between a hydrogen tank and a stack to shut off fuel.

[0007] The fuel shut-off valve includes a valve section for restricting fluid flow and a solenoid section for driving the valve section. The solenoid section, for controlling the valve section, includes a coil assembly for generating a magnetic field, a hollow core, a plunger movably mounted inside the core, and a plunger absorber provided on the plunger.

[0008] Incidentally, the fuel shut-off valve described above has a structure in which the plunger moves while in contact with the inner wall of the core. Therefore, when the solenoid unit operates to move the plunger, there was a problem in that friction with the core generated operating resistance. [Overview of the project] [Problems that the invention aims to solve]

[0009] The present invention aims to solve the problems of the prior art described above, and to provide a fuel shut-off valve that can reduce friction caused by contact between the core and the plunger and effectively eliminate operating resistance.

[0010] Furthermore, the present invention aims to provide a fuel shut-off valve that can improve the design flexibility within the engine compartment and solve problems caused by assembly interference with other parts. [Means for solving the problem]

[0011] The fuel shut-off valve according to the present invention is a valve installed in a valve body that includes a supply passage, a discharge passage, and a valve seat formed between the supply passage and the discharge passage, and controls the flow of fuel by opening and closing the valve seat.

[0012] Considering its configuration, it includes a housing with a connector integrally formed for power and signal transmission, a coil assembly provided inside the housing and electrically connected to the connector, a core coupled so as to penetrate the coil assembly and having a first operating groove formed therein, a plunger movably installed in the first operating groove and having a second operating groove formed therein that connects to the supply passage, a friction member interposed between the core and the plunger to reduce friction, a pilot movably installed in the second operating groove and having a pilot orifice formed therein that connects the second operating groove and the discharge passage, and a spring interposed between the core and the plunger to elastically support the plunger so that the pilot is in close contact with the valve seat. [Effects of the Invention]

[0013] As described above, the present invention, by interposing a friction member between the core and the plunger to reduce friction due to contact, can effectively eliminate the operating resistance of the plunger, thereby improving openness, airtightness, and noise reduction.

[0014] Furthermore, since the valve volume can be minimized by eliminating the operating resistance of the plunger, the design flexibility within the engine compartment can be improved, and problems caused by assembly interference with other parts can be solved. [Brief explanation of the drawing]

[0015] [Figure 1] This is a cross-sectional view of a fuel shutoff valve according to one embodiment of the present invention. [Figure 2] This is an enlarged view of a part of a fuel shutoff valve according to one embodiment of the present invention. [Figure 3] This figure shows the operating state of a fuel shutoff valve according to one embodiment of the present invention. [Figure 4] This figure shows the operating state of a fuel shutoff valve according to one embodiment of the present invention. [Figure 5] This figure shows the operating state of a fuel shutoff valve according to one embodiment of the present invention. [Modes for carrying out the invention]

[0016] Preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Where a specific description of known technology according to the present invention would obscure the gist of the invention, such detailed description will be omitted. Furthermore, the same reference numerals in the drawings are used to indicate identical or similar components.

[0017] Referring to Figures 1 and 2, the fuel shut-off valve 100 according to one embodiment of the present invention is a valve installed in a valve body 200 in which fuel transfer passages 210 to 230 are formed, and which controls the flow of fuel.

[0018] First, let's consider the valve body 200 in which the fuel shut-off valve 100 according to this embodiment is installed. A supply passage 210 is formed on one side of the valve body 200, and a discharge passage 230 is formed on the other side. A valve seat 230 is formed between the supply passage 210 and the discharge passage 220. At this time, the upper surface of the valve body 200 on which the valve seat 230 is formed is open, and the fuel shut-off valve 100 is installed on the open upper surface.

[0019] The valve seat 230 is the part that is opened and closed by the fuel shut-off valve 100, and although it protrudes towards the fuel shut-off valve 100, it has a tapered shape in which the diameter decreases towards the tip.

[0020] The fuel shut-off valve 100 consists of a housing 110, a coil assembly 120 provided inside the housing 110, a core 130 that penetrates the coil assembly 120, a plunger 140 movably installed inside the core 130, a friction member 150 interposed between the core 130 and the plunger 140, a pilot 160 movably installed inside the plunger 140, and a spring 170 that elastically supports the pilot 160.

[0021] The housing 110 is cylindrical with a sealed upper surface and an open lower surface. A connector 112 is formed on one side of the housing 110 for power and signal transmission. Further, a flange (not shown) is formed at the lower end of the housing 110 for connection with the valve box 200.

[0022] For reference, the fuel cut-off valve 100 is coupled to the valve box 200 via bolts (not shown) that penetrate the flange of the housing 110.

[0023] The coil assembly 120 is provided inside the housing 110 and is electrically connected to the connector 112. When power is applied through the connector 112, it generates a magnetic field.

[0024] The coil assembly 120 consists of a bobbin 122 and a coil 124 wound around the outer peripheral surface of the bobbin 122. The bobbin 222 is formed in a hollow spool shape and is made of an insulating material so as to electrically insulate between the coil 124 and the core 130. The coil 124 is the part where a magnetic field is generated when power is applied. At this time, the strength of the magnetic field generated is proportional to the current flowing along the coil 124 and the number of coils.

[0025] The core 130 is a fixed core that induces the magnetic field generated by the coil assembly 120. The core 130 extends in one direction (in the vertical direction in the drawing) and is coupled so as to penetrate the coil assembly 120 from the lower part to the upper part.

[0026] First operation grooves 132, 134 that are open downward are formed in the core 130. The first operation grooves 132, 134 consist of a small-diameter part 132 that guides the movement of the plunger 140 and a large-diameter part 134 that is formed below the small-diameter part 132 and is open to the valve seat 230 side.

[0027] A tapered magnetic force strengthening groove 136 is formed around the middle end of the core 130 corresponding to the upper end of the small-diameter part 132 to ensure magnetic force. Further, a damper 180 is provided in the large-diameter part 134 to absorb the impact generated when contacting the plunger 140.

[0028] The damper 180 is made of a material with a predetermined elasticity to absorb shocks and is formed in an annular shape so that it can be closely fitted to the inner circumferential surface of the large-diameter portion 134. At this time, a number of connecting grooves 182 are formed radially on the lower surface of the damper 180.

[0029] The connecting groove 182 is a passage for connecting the supply channel 210 and the first operating grooves 132 and 134, and more specifically, it allows the supply channel 210 and the first operating grooves 132 and 134 to remain connected even when the core 130 and the plunger 140 are in contact.

[0030] The plunger 140 is a movable core that moves by a magnetic field induced through the core 130 and is movably installed in the first working grooves 132 and 134 of the core 130.

[0031] The plunger 140 has a cylindrical shape that extends in the vertical direction. A flange 142 is formed at the lower end of the plunger 140, which contacts the damper 180 and limits the upward movement of the plunger 140. In this case, the flange 142 is formed with a diameter larger than the plunger 140 and smaller than the large-diameter portion 134.

[0032] A second working groove 142 is formed in the plunger 140, which is open downwards. The second working groove 142 is connected to the supply channel 210, and therefore a connecting hole 146 is formed around the lower part of the plunger 140 where the second working groove 142 is formed.

[0033] The friction member 150 is interposed between the core 130 and the plunger 140 to reduce friction caused by contact. The friction member 150 is in the form of a thin film or sheet, wound into a cylindrical shape, and attached to the inner wall of the first working groove 132. These friction members 150 are preferably made of polytetrafluoroethylene (PTFE) or a material containing the same, and are made to a thickness of 1.0 mm or less.

[0034] In this way, by reducing friction caused by contact between the core 130 and the plunger 140 via the friction member 150, the operating resistance of the plunger 140 can be effectively eliminated, thereby improving openness, airtightness, and noise reduction.

[0035] The pilot 160 is a means of opening and closing the passages 210-230 by moving due to the pressure of the fuel flowing in through the connecting hole 140. These pilots 160 are movably mounted in the second operating groove 144 of the plunger 140 and close or open the passages 210-230 when they come into contact with or separate from the valve seat 230.

[0036] The pilot 160 has a pilot orifice 162 that connects the second operating groove 144 and the discharge passage 220. The pilot 160 is also equipped with a first absorber 164 that absorbs the shock generated when it comes into contact with the valve seat and maintains airtightness. In this case, the diameter of the pilot orifice 162 is preferably 0.8 mm or less.

[0037] The second working groove 144, in which the pilot 160 is installed, is equipped with a second absorber 166 to absorb the impact generated when it comes into contact with the pilot 160 and to improve airtightness. In addition, the inner circumferential surface of the upper end of the second working groove 144 is equipped with a first stopper 192 which is pressed into the second working groove 144 and assembled to improve airtightness, and a stopper 194 is connected to the opening at the lower end of the second working groove 144 to prevent the pilot 160 from separating.

[0038] The spring 170 is interposed between the core 130 and the plunger 140, elastically supporting the plunger 140. The plunger 140, elastically supported by the spring 170, causes the pilot 160 to be deflected downward so that it is in close contact with the valve seat 230.

[0039] Referring to Figures 3 to 5, we will examine the operating state of the fuel shut-off valve according to this embodiment.

[0040] Figure 3 shows the state in which no power is applied to the fuel shut-off valve 100, Figure 4 shows the initial state in which power is applied to the fuel shut-off valve 100, and Figure 5 shows the later state in which power is applied to the fuel shut-off valve 100.

[0041] As shown in Figure 3, when no power is applied, the spring 170's elastic force causes the plunger 140 to descend, moving the pilot 160 downward. At this time, the pilot 160 contacts the valve seat 230, closing the valve seat 230 and thereby blocking the flow of fuel through the transfer passages 210-230.

[0042] As shown in Figure 4, in the initial stages when power is applied to the fuel shut-off valve 100, the plunger 140 rises slightly, forming a gap (G) between the pilot 160 and the second absorber 166, and fuel from the supply passage 210 is transferred to the discharge passage 220 side through the gap (G). At this time, since the pressure on the supply passage 210 side is greater than the pressure on the discharge passage 220 side, the pilot 160 is maintained in contact with the valve seat 230.

[0043] On the other hand, in the later stage when power is applied to the fuel shut-off valve 100, the plunger 140 rises completely, separating the pilot 160 from the valve seat 230. As a result, the valve seat 230 is opened, allowing fuel to flow through the transfer passages 210-230.

[0044] As described above, the present invention has been explained with reference to the illustrative drawings. However, the present invention is not limited to the embodiments and drawings disclosed herein, and it is clear that various modifications can be made by an ordinary person skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration described herein are not explicitly stated and explained in the embodiments of the present invention described above, the effects that can be predicted by such configurations should also be recognized.

Claims

1. A fuel shut-off valve is installed in a valve body including a supply channel, a discharge channel, and a valve seat formed between the supply channel and the discharge channel, and controls the flow of fuel by opening and closing the valve seat, A housing with an integrated connector for power and signal transmission; A coil assembly provided inside the housing and electrically connected to the connector; A core, which is coupled so as to penetrate the coil assembly and has a first working groove formed therein; A plunger movably installed in the first operating groove and having a second operating groove formed therein that is connected to the supply channel; A friction member interposed between the core and the plunger to reduce friction; A pilot movably installed in the second operating groove and having a pilot orifice formed therein that connects the second operating groove and the discharge passage; and Interposed between the core and the plunger is a spring that elastically supports the plunger so that the pilot is in close contact with the valve seat, Fuel shutoff valve.

2. The first operating groove consists of a small-diameter portion that guides the movement of the plunger and a large-diameter portion formed below the small-diameter portion and open to the valve seat side. The large-diameter portion is equipped with a damper to absorb the impact generated when it comes into contact with the plunger. The fuel shut-off valve according to claim 1.

3. The damper is characterized in that it has a connecting groove that connects the supply channel and the first operating groove, even when the core and the plunger are in contact. The fuel shut-off valve according to claim 2.

4. The plunger is characterized by having a connecting hole that connects the supply channel and the second operating groove. The fuel shut-off valve according to claim 3.

5. A flange is formed at one end of the plunger that contacts the damper, but the flange is characterized by being formed with a diameter smaller than the large diameter portion. The fuel shut-off valve according to claim 4.

6. The pilot is characterized by being equipped with a first absorber that absorbs the impact generated when it comes into contact with the valve seat and maintains airtightness. A fuel shut-off valve according to any one of claims 1 to 5.

7. The second operating groove is equipped with a second absorber that absorbs the shock generated when it comes into contact with the pilot and maintains airtightness. A fuel shut-off valve according to any one of claims 1 to 5.

8. The friction member is characterized by having a thickness of 1.0 mm or less that adheres to the inner wall of the first working groove. A fuel shut-off valve according to any one of claims 1 to 5.

9. The friction member is characterized by being a film made of polytetrafluoroethylene (PTFE) or a material containing the same. The fuel shut-off valve according to claim 8.

10. The diameter of the pilot orifice is characterized by being 0.8 mm or less. A fuel shut-off valve according to any one of claims 1 to 5.

Images