Valve assembly

Abstract

To provide a valve assembly for allowing easy inspection of a suction valve and a discharge valve constituting a pump and actualizing easy replacement of components.SOLUTION: A valve assembly A includes a suction flow path 13 formed in a region ranging from an outer face of a valve block 10 separably connected to a lower end of a cylinder 5 to a pump space S in a lower part of the cylinder 5, a suction valve Va arranged in a position where the suction flow path 13 is opened / closed, and adapted to be opened along with a pressure drop in the pump space S to make liquid hydrogen in a tank flow into the pump space S, a discharge flow path 14 formed in a region ranging from the pump space S to a discharge port 12, and a discharge valve Vb arranged in a position where the discharge flow path 14 is opened / closed, and adapted to be opened along with a pressure rise in the pump space S to make the liquid hydrogen in the pump space S flow into the discharge port 12.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a valve assembly. [Background technology]

[0002] As a valve assembly, Patent Document 1 discloses a fuel removal device in which a cylindrical insulating layer is formed on a fuel tank in which liquid hydrogen is stored, protruding downward, and a cylindrical body is provided that is movable vertically relative to this insulating layer, and a pump unit is disposed inside this cylindrical body.

[0003] The fuel removal device in Patent Document 1 shows a pump unit equipped with a piston, a cylinder, a suction valve, and a discharge valve, and a rod is used to reciprocate the piston, sucking in liquid hydrogen via the suction valve and sending it from the discharge valve to a fuel pipe for removal.

[0004] Patent Document 2 shows a configuration in which a vertically elongated pump housing that sucks in and pumps out liquid hydrogen from a hydrogen fuel tank has a cylindrical piston holder inside, the lower end of which is connected to the inside of the piston holder by a universal joint.

[0005] In Patent Document 2, the upper end of a cylinder holder housed inside a piston holder so as to be capable of vertically reciprocating is connected to a connecting rod by a universal joint, and a piston is housed inside the cylinder holder.

[0006] In the configuration of Patent Document 2, the connecting rod moves up and down, which causes the cylinder to move up and down within the pump housing. In response to this movement, the piston moves relatively within the cylinder, sucking in liquid hydrogen via the suction valve at the bottom end of the cylinder and sending it out through the discharge valve at the top end of the piston. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 62-102000 [Patent Document 2] Japanese Patent Application Publication No. 7-4350 Summary of the Invention [Problem to be solved by the invention]

[0008] In both the pumps disclosed in Patent Document 1 and Patent Document 2, a rod (such as a connecting rod) is reciprocated up and down, and a suction valve and a discharge valve are alternately opened and closed by the pressure difference caused by the up and down movement of a piston connected to the rod, thereby delivering liquid hydrogen.

[0009] In each document, the suction valve is located at the lower end of the pump, but in Patent Document 1, the discharge valve is located parallel to the piston, and in Patent Document 2, the discharge valve is located above the piston.

[0010] The device shown in Patent Document 1 has a cylindrical body that can be freely moved up and down relative to a cylindrical insulation layer formed in the fuel tank, and is configured to enable the pump unit to be inserted and removed from this cylindrical body, but it is not easy to inspect the discharge valve.

[0011] Furthermore, the pump disclosed in Patent Document 2 has a suction valve and a discharge valve disposed inside a piston holder and spaced apart in the vertical direction, making maintenance difficult.

[0012] For these reasons, there is a demand for a valve assembly that allows easy inspection of the suction valves and discharge valves that make up the pump, and also allows easy replacement of parts. [Means for solving the problem]

[0013] A characteristic configuration of a valve assembly according to the present invention is a valve assembly which is inserted below the liquid level of a tank in which liquid hydrogen is stored, is provided at the lower end of a cylinder which allows liquid hydrogen to be drawn from the tank, and supplies and discharges liquid hydrogen by operation of a piston housed in the cylinder, and which comprises a valve block which is detachably connected to the lower end of the cylinder, an intake passage formed in an area extending from the outer surface of the valve block to a pump space below the cylinder, an intake valve which is positioned to open and close the intake passage and opens as pressure in the pump space drops, thereby allowing liquid hydrogen stored in the tank to flow into the pump space, a discharge passage formed in an area extending from the pump space to a discharge port formed in the valve block, and a discharge valve which is positioned to open and close the discharge passage and opens as pressure in the pump space rises, thereby allowing liquid hydrogen in the pump space to flow to the discharge port.

[0014] In this configuration, by removing the cylinder from the tank, it is possible to visually check the suction valve and discharge valve on the valve block, and they can be easily adjusted or replaced. In addition, by separating the valve block from the lower end of the cylinder, it is possible to not only replace the suction valve and discharge valve, but also adjust their positions. This configuration shortens the suction flow path and discharge flow path formed in the valve block, and also makes it possible to miniaturize the valve assembly. In this way, a valve assembly has been configured that makes it easy to inspect the suction valve and discharge valve that make up the pump, and to easily replace parts. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is a cross-sectional view showing a pump unit provided in a tank for storing liquid hydrogen. [Diagram 2] FIG. 4 is a cross-sectional view of the valve assembly during intake actuation. [Diagram 3] FIG. 2 is a cross-sectional view of the valve assembly during a dispensing operation. [Figure 4] FIG. 2 is a plan view of the valve assembly. [Diagram 5] FIG. 2 is a bottom view of the valve assembly. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] An embodiment of the valve assembly A according to the present invention will be described below with reference to the drawings. In this embodiment, the shape of the valve block 10, the arrangement of the suction valve Va and the discharge valve Vb, and the configuration thereof are not limited to the following embodiment, and various modifications are possible without departing from the spirit of the invention.

[0017] [Basic configuration] Fig. 1 shows a pump unit P that extracts liquid hydrogen stored in a tank T provided on a vehicle. The vehicle vaporizes the liquid hydrogen supplied from the pump unit P in a vaporizer C and supplies it to an engine E, which is a reciprocating internal combustion engine. With this configuration, the vehicle is a hydrogen vehicle that runs using the driving force of the engine E generated by the combustion of hydrogen gas.

[0018] The pump unit P is equipped with a crank mechanism 2 that converts the rotational driving force of the electric motor 1 into reciprocating motion, and is also equipped with an operating rod 3, a cylindrical rod case 4, a cylinder 5, a piston 6, a valve assembly A, and an extraction pipeline 7 (an example of an extraction flow path).

[0019] In this pump unit P, a cylindrical cylinder 5 is connected to the lower end of a rod case 4, and a piston 6 is housed in this cylinder 5. The piston 6 is connected to the lower end of the operating rod 3, and reciprocates inside the cylinder 5 by the driving force transmitted from the crank mechanism 2 to the operating rod 3.

[0020] As shown in FIGS. 2 and 3, the valve assembly A includes a suction valve Va, a discharge valve Vb, and a discharge port 12.

[0021] 2, the valve assembly A opens the suction valve Va by the action of negative pressure caused by the operation of the piston 6 to draw in liquid hydrogen, and opens the discharge valve Vb by the increase in pressure caused by the operation of the piston 6 to send the liquid hydrogen that has already been drawn in to the discharge port 12. The liquid hydrogen sent to the discharge port 12 in this way is sent to the vaporizer C through the single extraction pipe 7.

[0022] In particular, the operating rod 3, the rod case 4, the cylinder 5, the piston 6, and the valve block 10 of the valve assembly A are each formed from a metal material.

[0023] Although the pump unit P can be used in an oblique position, it is used with the crank mechanism 2 on the upper side and the valve assembly A on the lower side as shown in Fig. 1. For this reason, the upper and lower sides of the pump unit P and the valve assembly A will be described in accordance with the vertical relationship shown in Fig. 1.

[0024] The pump unit P also includes a crank mechanism 2 outside the tank T, and a rod case 4 protruding downward from the lower part of the crank mechanism 2. The rod case 4 is disposed so that its lower end is located below the liquid level L of the liquid hydrogen.

[0025] Tank T has an outer wall made of a heat insulating material to keep liquid hydrogen in a low temperature liquid state. Tank T has a collector part Ta that protrudes downward from the lower surface of the outer wall, and a valve assembly A is disposed inside this collector part Ta.

[0026] [Valve Assembly] 2 to 5, the valve assembly A includes a valve block 10 that is detachably connected to the lower end of the cylinder 5, and an intake valve Va and a discharge valve Vb that are attached to the valve block 10. The valve block 10 also includes a discharge port 12 that delivers liquid hydrogen from the discharge valve Vb.

[0027] The valve block 10 has a cylindrical portion 11 formed on its upper surface, which protrudes upward. A female thread is formed on the inner surface of this cylindrical portion 11. A female thread that can be screwed into the male thread of the cylindrical portion 11 is formed on the outer surface of the lower end of the cylinder 5. As a result, the valve block 10 is connected to the cylinder 5 by screwing into the male thread formed on the outer periphery of the lower end of the cylinder 5.

[0028] In the valve assembly A, a pump space S is formed inside a cylindrical portion 11, below a region of the lower end side of the cylinder 5 where the piston 6 operates.

[0029] The valve block 10 has multiple (two in this embodiment) intake passages 13 in the area connecting the bottom surface of the valve block 10 and the pump space S inside the cylindrical portion 11, and has multiple (three in this embodiment) discharge passages 14 in the area connecting the pump space S and the discharge port 12.

[0030] The suction flow passage 13 and the discharge flow passage 14 formed in the valve block 10 do not have to be multiple, and either or both of the suction flow passage 13 and the discharge flow passage 14 may be single.

[0031] [Valve assembly: suction valve] 2 and 3, the valve block 10 is provided with an intake valve Va in each of the two intake passages 13. The intake valve Va has a metal or resin intake valve element 15 and a metal intake spring 16 that biases the intake valve element 15 to a closed position. Note that Figures 2 and 3 show one intake passage 13 and one intake valve element 15 that opens and closes this intake passage 13.

[0032] The suction valve body 15 is integrally formed with a disk-shaped valve head portion 15a and a rod-shaped stem portion 15b.

[0033] The valve assembly A supports the suction valve element 15 with a stem portion 15b slidably inserted into the valve block 10. The suction valve element 15 opens and closes the suction flow passage 13 at the valve head portion 15a by moving along the insertion direction of the stem portion 15b.

[0034] The suction valve body 15 has a spring bearing 17 (an example of a movable body) at a portion of the stem portion 15b that protrudes toward the lower surface of the valve block 10, and has a compression coil type suction spring 16 between the spring bearing 17 and the lower surface of the valve block 10. The spring bearing 17 is fitted onto the stem portion 15b and is maintained in a retaining state by a fixing pin 17a that is inserted into an engagement hole perpendicular to the longitudinal direction of the stem portion 15b (see FIG. 5).

[0035] As a result, the intake valve body 15 is maintained in a closed position in which the valve head portion 15a abuts against the opening of the intake passage 13 on the pump space S side by the biasing force of the intake spring 16, as shown in Figure 3, and as a result, the flow of liquid hydrogen in the intake passage 13 is blocked.

[0036] [Valve assembly: discharge valve] 2 and 3, the valve block 10 is provided with a discharge valve Vb in each of the three discharge flow paths 14. The discharge valve Vb has a discharge valve element 18 made of metal or resin, a discharge spring 19 made of metal such as spring steel that biases the discharge valve element 18 to a closed position, and a metal plug 20 (an example of a fixed body) that supports the discharge valve element 18 in a manner that accommodates it therein. Note that one discharge flow path 14 and one discharge valve element 18 that opens and closes this discharge flow path 14 are shown in FIGS. 2 and 3.

[0037] The discharge flow path 14 has an upstream portion 14a extending from the pump space S to the underside of the valve block 10, and a downstream portion 14b branching off from the upstream portion 14a at a location where the discharge valve body 18 is located and extending to the discharge port 12.

[0038] The discharge valve body 18 is supported so as to be slidable in the fitting space of the plug 20, and is biased to protrude by the biasing force of a compression coil type discharge spring 19 provided between the discharge valve body 18 and the plug 20. The plug 20 is fixed to the valve block 10 from the outside of the valve block 10 by a screw type.

[0039] As a result, the discharge valve body 18 is maintained in the closed position by abutting against a contact portion formed in the upstream portion 14a of the discharge flow path 14 as shown in FIG. 2, and as a result, the flow of liquid hydrogen in the discharge flow path 14 is blocked.

[0040] This valve assembly A has three discharge flow paths 14, and therefore also has three upstream portions 14a and three downstream portions 14b of the discharge flow paths 14, as shown in FIG.

[0041] With this configuration, as shown in Fig. 2, the valve assembly A opens the suction valve Va due to the action of negative pressure from the pump space S as the piston 6 rises, causing liquid hydrogen to flow and be drawn into the pump space S. In addition, as shown in Fig. 3, the valve assembly A opens the discharge valve Vb as the pressure in the pump space S increases as the piston 6 descends, causing liquid hydrogen in the pump space S to flow and be discharged from the discharge port 12 to the extraction pipeline 7.

[0042] [Effects of the embodiment] In the valve assembly A, the intake valve Va and the discharge valve Vb are maintained in the closed position while the piston 6 is stopped, so that liquid hydrogen is not supplied to the extraction pipeline 7 (extraction flow path).

[0043] In particular, the valve assembly A is provided with a single valve block 10, an intake valve body 15, an exhaust valve body 18, and an exhaust port 12. Therefore, by removing the pump unit P from the tank T, an operator can expose the intake valve body 15 and the exhaust valve body 18 provided in the valve block 10, and visually check their condition, and can easily perform maintenance such as adjustment and replacement.

[0044] In addition, since the valve block 10 is attached to the lower end of the cylinder 5 with a screw, the entire valve assembly A can be easily removed from the lower end of the cylinder 5, making it easy to adjust and replace the suction valve body 15 and the discharge valve body 18.

[0045] Valve assembly A is configured to draw liquid hydrogen into suction passage 13 of valve block 10, send this liquid hydrogen through discharge passage 14 to discharge port 12, and send it from discharge port 12 to extraction pipeline 7. This configuration makes it possible to shorten the flow passages formed inside valve block 10.

[0046] [Another embodiment] The present invention may be configured as follows other than the above-described embodiment (common numbers and symbols as in the embodiment are used to designate components having the same functions as in the embodiment).

[0047] (a) In a configuration in which a plurality of suction passages 13 are formed in the valve block 10, the number of suction valve bodies 15 is different from the number of suction passages 13.

[0048] As one example, four suction passages 13 are formed to draw in liquid hydrogen from outside the valve block 10, and two sets of combined passages (not shown) are formed by merging the four suction passages 13 with two suction passages 13, and each combined passage is provided with an suction valve body 15. In this configuration, the number of suction valve bodies 15 used is fewer than the number of suction passages 13 that draw in liquid hydrogen from outside the valve block 10, making it possible to reduce the number of parts.

[0049] As a configuration including the concept of the alternative embodiment (a), a greater number of suction valve bodies 15 are used than the number of suction passages 13. In such a configuration, even if one of the suction valve bodies 15 does not operate properly, the other suction valve bodies 15 enable proper suction of liquid hydrogen.

[0050] (b) In a configuration in which a plurality of discharge flow paths 14 are formed in the valve block 10, the valve block 10 is provided with a number of discharge valve bodies 18 which differs from the number of discharge flow paths 14.

[0051] This alternative embodiment (b) has a configuration that shares a common concept with the alternative embodiment (a) previously described, and as can be inferred from the specific configuration described in alternative embodiment (a), it allows for a reduction in the number of parts and enables proper discharge of liquid hydrogen.

[0052] (c) A portion of the suction passage 13 and a portion of the discharge passage 14 may be formed by a pipe arranged outside the valve block 10.

[0053] Furthermore, the configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, provided that no contradiction arises. Furthermore, the embodiments disclosed in this specification are merely examples, and the embodiments of the present invention are not limited thereto, and can be appropriately modified within the scope that does not deviate from the purpose of the present invention.

[0054] In the above-described embodiment, the following configurations are envisaged. (1) A valve assembly A is inserted below the liquid level of a tank T in which liquid hydrogen is stored, and is provided at the lower end of a cylinder 5 to allow liquid hydrogen to be extracted from the tank T, and supplies and discharges liquid hydrogen by the operation of a piston 6 contained in the cylinder 5. This valve assembly A is equipped with a valve block 10 which is detachably connected to the lower end of the cylinder 5, an intake passage 13 formed in an area extending from the outer surface of the valve block 10 to a pump space S below the cylinder 5, an intake valve Va which is positioned to open and close the intake passage 13 and opens as the pressure in the pump space S drops, thereby allowing the liquid hydrogen stored in the tank T to flow into the pump space S, a discharge passage 14 which is formed in an area extending from the pump space S to a discharge port 12 formed in the valve block 10, and a discharge valve Vb which is positioned to open and close the discharge passage 14 and opens as the pressure in the pump space S rises, thereby allowing the liquid hydrogen in the pump space S to flow into the discharge port 12.

[0055] According to this, by removing the cylinder 5 from the tank T, the valve assembly A can be removed integrally with the cylinder 5, making it possible to visually check the suction valve Va and discharge valve Vb provided in the valve block 10, and to easily adjust or replace them. In addition, by separating the valve block 10 from the lower end of the cylinder 5, it becomes possible not only to replace the suction valve Va and discharge valve Vb, but also to adjust their positions. This configuration shortens the suction flow path 13 and discharge flow path 14 formed in the valve block 10, making it possible to reduce the size of the valve assembly A.

[0056] (2) In the valve assembly A of (1), it is preferable that the intake valves Va arranged corresponding to each of the plurality of intake passages 13 and the exhaust valves Vb arranged corresponding to each of the plurality of exhaust passages 14 are arranged in the valve block 10.

[0057] In this configuration, in conjunction with the operation of the piston 6, the valve block 10 can suck liquid hydrogen into the pump space S and deliver the liquid hydrogen already sucked into the pump space S from the discharge port 12. In particular, since the valve block 10 is provided with a plurality of suction passages 13, a plurality of suction valves Va, a plurality of discharge passages 14, and a plurality of discharge valves Vb, even if some of these do not function properly, it will result in some degradation in performance, but it is still possible to deliver liquid hydrogen.

[0058] In the valve assembly A of (3)(2), it is preferable that the discharge flow path 14 has a single extraction flow path (extraction pipeline 7) that joins the liquid hydrogen discharged from the multiple discharge valves Vb and discharges it from the discharge port 12.

[0059] According to this, when pumping out liquid hydrogen from the pump space S, multiple discharge flow paths 14 and multiple discharge valves Vb are used, which enables reliable delivery even if, for example, one of the discharge flow paths 14 or discharge valves Vb does not function satisfactorily.

[0060] (4) In any one of the valve assemblies A of (1) to (3), it is preferable that the suction valve Va has a suction valve body 15 capable of opening and closing the suction flow path 13, a suction spring 16 that urges the suction valve body 15 to a closed position, and a movable body (spring receiver 17) connected to the suction spring 16 on the outer surface of the valve block 10 while being fixed to the suction valve body 15, and the discharge valve Vb has a discharge valve body 18 capable of opening and closing the discharge flow path 14, a discharge spring 19 that urges the discharge valve body 18 to a closed position, and a fixed body (plug 20) that houses the discharge spring 19 and supports the discharge valve body 18 and is fixed to the outer surface of the valve block 10.

[0061] With this, by setting the biasing force of the suction spring 16 and the biasing force of the discharge spring 19, it becomes possible to suck in and send out liquid hydrogen stored in the tank T in conjunction with the operation of the piston 6. Also, because the movable body (spring receiver 17) and fixed body (plug 20) are structured to be disposed outside the valve block 10, it is easy to remove the movable body (spring receiver 17) and fixed body (plug 20) from the valve block 10, facilitating their inspection and replacement. [Industrial Applicability]

[0062] The present invention can be utilized in a valve assembly. [Explanation of symbols]

[0063] A: valve assembly, S: pump space, T: tank, Va: suction valve, Vb: discharge valve, 5: cylinder, 6: piston, 7: extraction pipe line (extraction flow path), 10: valve block, 13: suction flow path, 14: discharge flow path, 15: suction valve body (suction valve), 16: suction spring, 17: spring receiver (movable body), 18: discharge valve body (discharge valve), 19: discharge spring, 20: plug (fixed body)

Claims

1. A valve assembly which is inserted below the liquid level of a tank in which liquid hydrogen is stored, is provided at the lower end of a cylinder which allows liquid hydrogen to be drawn from the tank, and supplies and discharges liquid hydrogen by the operation of a piston housed in the cylinder, a valve block detachably connected to a lower end of the cylinder; an intake passage formed in a region extending from an outer surface of the valve block to a pump space at a lower portion of the cylinder; an intake valve that is disposed at a position for opening and closing the intake passage and opens in response to a pressure drop in the pump space to allow the liquid hydrogen stored in the tank to flow into the pump space; a discharge passage formed in a region extending from the pump space to a discharge port formed in the valve block; a discharge valve that is disposed at a position to open and close the discharge passage and opens as the pressure in the pump space increases, thereby allowing liquid hydrogen in the pump space to flow to the discharge port.

2. 2. The valve assembly according to claim 1, wherein the suction valves arranged corresponding to each of the plurality of suction passages and the discharge valves arranged corresponding to each of the plurality of discharge passages are arranged in the valve block.

3. 3. The valve assembly according to claim 2, wherein the discharge flow passage has a single outlet flow passage that joins together liquid hydrogen discharged from a plurality of the discharge valves and discharges the liquid hydrogen from the discharge port.

4. the suction valve includes an suction valve body capable of opening and closing the suction flow path, an suction spring that biases the suction valve body to a closed position, and a movable body that is fixed to the suction valve body and is connected to the suction spring on an outer surface of the valve block, The valve assembly according to any one of claims 1 to 3, wherein the discharge valve includes a discharge valve body capable of opening and closing the discharge flow path, a discharge spring that biases the discharge valve body to a closed position, and a fixed body that houses the discharge spring and supports the discharge valve body and is fixed to an outer surface of the valve block.

Images