WO2010146968A1

WO2010146968A1 - Liquefied gas fuel supply device

Info

Publication number: WO2010146968A1
Application number: PCT/JP2010/058650
Authority: WO
Inventors: 恵司岩月; 秀幸稲垣; 靖中谷
Original assignee: 中央精機株式会社; 株式会社ハマイ
Priority date: 2009-06-19
Filing date: 2010-05-21
Publication date: 2010-12-23
Also published as: JPWO2010146968A1; CN102459857B; JP5496196B2; KR20120049176A; CN102459857A

Abstract

Provided is a liquefied gas fuel supply device that, even if an accelerator is operated suddenly, can accurately follow said operation and stably carry out an appropriate engine operation. If it is determined from a supply flow volume determination value that a flow volume in a fuel supply pipe and/or the engine is anomalous, a valve opening/closing control means closes off a narrow openable/closeable channel by actuating an actuated valve in an electromagnetic valve device interposed between a fuel supply pump and the fuel supply pipe, thereby switching a main valve to a closed position and forcibly shutting off supply of a liquefied gas fuel from the fuel supply pump in a fuel tank to the fuel supply pipe. Thus, even if an excessive pressure differential arises due to sudden accelerator operation, said accelerator operation can be reliably followed and an appropriate engine operation can be stably carried out.

Description

Liquefied gas fuel supply device

The present invention relates to a liquefied gas fuel supply device for storing and supplying liquefied gas fuel such as DME (dimethyl ether) and LPG (liquefied petroleum gas) used as engine fuel to the engine.

For example, vehicles such as automobiles tend to increase the number of vehicles using liquefied gas fuel for the purpose of low pollution in accordance with the recent tightening of exhaust gas regulations. As the liquefied gas fuel, liquefied petroleum gas (hereinafter referred to as LPG) fuel is mainstream, but dimethyl ether (hereinafter referred to as DME) fuel is also attracting attention. This DME fuel has an excellent advantage that it has a high cetane number, and can significantly reduce the emission amount of PM and NOx, and is also highly expected as a low pollution measure.

The above-described automobile using liquefied gas fuel as a fuel is provided with a fuel supply device for storing the liquefied gas fuel and supplying the liquefied gas fuel to the engine. Here, the fuel tank for storing the liquefied gas fuel is mounted on the trunk, the lower part of the side of the vehicle body, and a supply pipe for supplying the liquefied gas fuel from the fuel tank to the engine is disposed. In recent years, a fuel supply pump is disposed in the fuel tank, and the fuel consumption improvement effect is enhanced by controlling the flow rate of the liquefied gas fuel supplied to the engine by the fuel supply pump. An overflow prevention valve is provided between the fuel supply pump and the supply pipe to prevent excessive liquefied gas fuel from flowing into the supply pipe. This overflow prevention valve automatically closes when the outflow of liquefied gas fuel becomes abnormal due to damage to the supply pipe, etc., and reliably prevents the outflow of liquefied gas fuel. It is generally known that the valve body is automatically closed when a pressure exceeding the urging force is applied to the valve body opened according to the urging force of the spring ( For example, Patent Document 1).

In addition, such a fuel supply device is provided with a return pipe for returning surplus liquefied gas fuel that has not been used in the engine to the fuel tank, and is liquefied from the fuel tank at the downstream end of the return pipe. A check valve for preventing the backflow of the gas fuel is provided.

Japanese Utility Model Publication No. 1-94682

In the fuel supply device described above, when the vehicle is mounted on an automobile, the fuel supply pump is controlled to operate according to the accelerator operation. Therefore, for example, if the flow rate of the liquefied gas fuel from the fuel supply pump suddenly increases or decreases due to a rapid operation of the accelerator, an excessive pressure fluctuation occurs and the differential pressure before and after the overflow prevention valve tends to increase instantaneously. . If an instantaneous increase in the differential pressure occurs in this way, there is a concern that the overflow prevention valve malfunctions, causing engine malfunction and the like.

In particular, in a fuel supply apparatus using DME fuel as liquefied gas fuel, the operation control of the fuel supply pump is performed with higher accuracy than in a configuration using LPG fuel. As a result, the flow rate of the liquefied gas fuel supplied to the engine can be controlled with high accuracy, and surplus liquefied gas fuel that is not used in the engine can be reduced as much as possible, so that an improvement in fuel consumption can be obtained. However, when the fuel supply pump is controlled with high accuracy in this way, as described above, there is a tendency that a large differential pressure is likely to be generated instantaneously before and after the overflow prevention valve, and the problems associated therewith also occur remarkably. Is concerned.

The present invention proposes a liquefied gas fuel supply device capable of properly supplying liquefied gas fuel to an engine even when a large differential pressure is suddenly generated by a fuel supply pump.

The present invention includes a fuel tank that stores liquefied gas fuel to be supplied to an engine, a fuel supply pump that is disposed in the fuel tank and pumps the liquefied gas fuel in the fuel tank at a predetermined flow rate, and a fuel supply pump. In a liquefied gas fuel supply device including a fuel supply pipe for supplying the liquefied gas fuel fed to the engine, a first gas flow port and a second gas flow port capable of flowing in and out of the liquefied gas fuel are provided. A casing body, an open position that is disposed in the casing body, forms a variable closed region that is hermetically partitioned from the second gas flow port, and communicates the first gas flow port and the second gas flow port; A main valve for converting the position to the closed position to be closed, an urging means for urging the main valve toward the closed position, and a casing body, and the variable closed area and the first gas flow port are always in communication with each other. Narrow channel and case An open / close narrow channel provided in the ring body for communicating the variable closed region and the second gas flow port, a communication position for opening the open / close narrow channel to communicate the variable closed region and the second gas flow port, An electromagnetic valve device comprising: an actuating valve that converts a position to a non-communication position that shields a path; and an actuating valve drive means that converts the operation valve to a communication position and a non-communication position. Is provided between the fuel supply pump and the fuel supply pipe, and is supplied to the engine through the fuel supply pipe so that the second gas flow port is on the fuel supply pipe side. The flow rate of the liquefied gas fuel detected by the flow rate detection sensor provided in the fuel supply pipe or / and the engine during driving of the engine is set in advance to determine the supply flow rate judgment value for judging the flow rate abnormality of the liquefied gas fuel. Based on the supply flow rate judgment value, When it is determined that the flow rate is low, the main valve is moved to the closed position by drivingly controlling the operating valve driving means so that the operating valve of the electromagnetic valve device is in the non-communication position. A liquefied gas fuel supply device comprising valve opening / closing control means for performing control for stopping supply of liquefied gas fuel from the fuel supply pipe to the fuel supply pipe.

Here, the flow rate detection sensor may be a sensor that directly detects the flow rate of the liquefied gas fuel, or the pressure detection sensor that detects the pressure in the fuel supply pipe or the pressure of the gas flow path in the engine. The flow rate may be indirectly detected by the pressure detected by the detection sensor. In the latter case, in order to determine the pressure detected by the pressure detection sensor, it is possible to set a predetermined pressure value as the supply flow rate determination value and thereby directly determine the detected pressure. In addition, it is preferable that the flow rate detection sensor provided in the engine is provided in the vicinity of the fuel injection pump provided in the engine. Further, the flow rate detection sensor may be a sensor that detects the rotational speed of the fuel supply pump or the fuel injection pump, and the flow rate may be indirectly detected based on the rotational speed detected by the sensor. On the other hand, the abnormal flow rate of liquefied gas fuel determined by the supply flow rate determination value means that when the flow rate in the fuel supply pipe significantly increases or decreases compared to the flow rate pumped by the fuel supply pump due to gas leakage or the like, Or it is a case where the flow volume supplied to an engine reduces remarkably compared with the flow volume pumped by a fuel supply pump.

In such a configuration, when it is determined that the flow rate of the liquefied gas fuel detected by the flow rate detection sensor is an abnormal flow rate based on the supply flow rate determination value, the solenoid valve device is controlled to be closed to control the operation from the fuel supply pump. Since the supply of the liquefied gas fuel is forcibly stopped, the same effect as the above-described conventional overflow prevention valve can be exhibited, and the overflow prevention valve is not required. It has become. And if there is no abnormality in the flow rate in the fuel supply pipe and / or the engine, the supply of the liquefied gas fuel by the solenoid valve device is maintained, and as described above, an excessive differential pressure was generated by a sudden accelerator operation. Even in this case, the supply through the electromagnetic valve device is maintained, and the same engine malfunction as in the case where the conventional overflow prevention valve malfunctions does not occur. Furthermore, since the operation control of the electromagnetic valve device is controlled based on the flow rate detected by the flow rate detection sensor, accurate and stable operation control can be performed. Therefore, according to this configuration, it is possible to reliably and accurately follow a sudden accelerator operation, and it is possible to stably perform an appropriate engine operation.

In addition, this structure can demonstrate the above-mentioned effect more effectively, when controlling a fuel supply pump with high precision using DME fuel as liquefied gas fuel. That is, even if the operation control of the fuel supply pump is controlled with higher accuracy, the engine operation is appropriate and stable, so that the effect of improving fuel consumption is further increased.

Here, in the electromagnetic valve device, the main valve is subjected to position conversion operation by controlling the operation of the operation valve, so that the first gas flow port and the second gas flow port are in a communication state and a non-communication state. It is to be converted. Specifically, when the operating valve is in the communication position, the first gas flow port and the second gas flow port communicate with each other via the narrow channel, the variable closed region, and the open / close narrow channel. The pressure in the position direction acts and the main valve is in the open position. Further, when the operating valve is in the non-communication position, the liquefied gas fuel that has flowed into the variable closing area via the narrow flow path increases the internal pressure of the variable closing area, and the main valve becomes the closing position. Liquefied gas fuel does not flow to the gas outlet. That is, when the valve opening / closing control means detects a flow rate abnormality based on the supply flow rate determination value, the supply valve to the fuel supply pipe is forcibly controlled by controlling the operation valve to the non-communication position. Can be stopped.

Furthermore, the solenoid valve device can reduce the pressure acting on the operating valve by reducing the flow passage area of the open / close narrow channel opened and closed by the operating valve as compared to the flow path opened and closed by the main valve. Therefore, the driving force (thrust) for operating the operating valve can be reduced, and the power consumption required for the operating valve driving means can be suppressed. And since it can respond to a large flow rate with a small thrust, it is more efficient than a general electromagnetic valve (so-called direct acting type) that directly opens and closes the flow path. Further, by setting the channel area of the open / close narrow channel to be equal to or less than the channel area of the narrow channel that communicates the first gas flow port and the variable closed region, the position of the main valve can be appropriately changed.

In the liquefied gas fuel supply device described above, the solenoid valve device opens the first gas flow port so that the liquefied gas fuel can flow in and out from the first gas flow port, and the first gas flow port A configuration is proposed in which a manual valve that is position-converted by a manual operation is provided at a closed position in which the liquefied gas fuel cannot be flowed in and closed. Here, the manual valve may have a configuration in which the first gas flow port itself is directly closed, or a substantially first configuration such as a configuration in which a communication path communicating with the first gas flow port is closed. The gas flow port may be closed.

In such a configuration, the electromagnetic valve device includes a manual valve that forcibly closes the first gas flow port so that the liquefied gas fuel cannot flow in and out from the first gas flow port regardless of the operation control of the operation valve. Therefore, it has both an open / close operation control function based on the flow rate detected by the flow rate detection sensor and an open / close function by manually operating the manual valve, which is highly useful. Furthermore, even if the open / close narrow channel cannot be shielded due to defective operation control of the operating valve, damage to the operating valve, etc., by holding the manual valve at the closed position, Inflow and out of the liquefied gas fuel can be reliably prevented. Also, for example, when the fuel tank is maintained or replaced, when the fuel tank is removed from or attached to the vehicle, the operation valve is kept in the closed position so that the liquefied gas fuel can be safely operated without leaking. can do. In addition, as this operation valve, the structure screwed by the casing body can be used suitably as a structure hold | maintained in a retracted position and a shielding position, respectively.

In the above-described liquefied gas fuel supply device, the solenoid valve device is manually operated at a retracted position where the main valve can be converted into an open position and a closed position, and a shield position where the main valve is held at the closed position. A configuration including a valve closing operation member whose position is changed by operation is proposed.

In such a configuration, the electromagnetic valve device includes a valve closing operation member capable of forcibly converting the position of the main valve to the closed position separately from the operation control of the operating valve. It has both an opening / closing operation control function based on the flow rate and an opening / closing function by manually operating the valve closing operation member, and is highly useful. For example, when the fuel tank is maintained or replaced, when removing or installing the fuel tank from the automobile, the valve closing operation member is placed in the shielding position so that the liquefied gas fuel can be safely operated without leaking. can do. In addition, as this valve closing operation member, the thing of the rod-shaped structure screwed together by the casing body can be used suitably as a structure hold | maintained in a retracted position and a shielding position, respectively.

The liquefied gas fuel supply device described above is provided with a return pipe for returning surplus liquefied gas fuel from the engine to the fuel tank, the electromagnetic valve device having the first gas flow port as the fuel tank side, and A pressure detection sensor disposed between the fuel tank and the return pipe so that the second gas flow port is located on the return pipe side, and the valve opening / closing control means is disposed on the return pipe during engine operation. When the pressure in the return pipe detected by the above is less than or equal to a preset return pressure threshold, the main valve driving means is driven to control the main valve so that the main valve is in the non-communication position. A configuration is proposed in which control is performed to prevent the backflow of the liquefied gas fuel from the fuel tank to the return pipe by changing the position of the valve to the closed position.

Here, in the configuration provided with the return pipe for returning the surplus liquefied gas fuel from the engine, conventionally, as described above, a check valve is provided to prevent the backflow from the fuel tank. In this configuration, the above-described electromagnetic valve device is provided and the electromagnetic valve device exerts the same effect as the check valve, and does not require a check valve. As the operation control of the electromagnetic valve device, if the pressure in the return pipe is larger than the return pressure threshold, the liquefied gas fuel returned from the return pipe moves the main valve toward the open position by maintaining the operation valve in the communication position. Press and flow into the fuel tank. On the other hand, if the pressure in the return pipe is equal to or lower than the return pressure threshold, the operating valve is set to the non-communication position. Here, if the pressure in the return pipe is larger than the internal pressure of the fuel tank with the operating valve in the non-communication position, the main valve is pressed toward the open position by the pressure difference, and the return pipe and the fuel tank communicate with each other. Maintained in a state. In this case, since the internal pressure in the return pipe is higher than the internal pressure of the fuel tank, no backflow occurs from the fuel tank. Further, when the pressure in the return pipe becomes smaller than the internal pressure of the fuel tank with the operating valve in the non-communication position, the internal pressure of the variable closed region communicating with the fuel tank through the narrow channel increases, and the main valve The position is converted to the closed position. Thereby, the backflow from a fuel tank can be prevented. As described above, in the present configuration, when the pressure in the return pipe detected by the pressure detection sensor provided in the return pipe becomes less than or equal to a preset return pressure threshold value while the engine is being driven, When the operation valve of the solenoid valve device is maintained in the non-communication position, and the pressure in the return pipe becomes smaller than the internal pressure of the fuel tank, the main valve is converted into the closed position, so that the reverse flow from the fuel tank Can be prevented. The return pressure threshold can be set as appropriate as a pressure value larger than the internal pressure of the fuel tank. For example, the return pressure threshold may be set to a maximum pressure value determined as the internal pressure of the fuel tank.

Furthermore, in this configuration, the same solenoid valve device as that connected to the fuel supply pump is interposed between the fuel tank and the return pipe. The effect of reducing the cost required for manufacturing and purchase can be achieved.

In the liquefied gas fuel supply apparatus described above, when the engine is stopped, the valve opening / closing control means drives and controls the operation valve drive means so as to hold the operation valve of the electromagnetic valve device in the non-communication position, and the engine starts. Then, the structure which is made to drive-control an operating valve drive means so that the operating valve of an electromagnetic valve apparatus may be hold | maintained in a communicating position is proposed.

In such a configuration, when the engine is stopped, the operating valve of the electromagnetic valve device is held in the non-communication position, whereby the main valve is held in the closed position, and the outflow of the liquefied gas fuel from the fuel tank can be reliably prevented. . When the engine is driven, the solenoid valve device connected to the fuel supply pipe can supply fuel to the fuel supply pipe by setting the operation valve to the communication position. Moreover, in the structure which connected the solenoid valve apparatus to the above-mentioned return pipe, if the pressure in a return pipe is larger than the internal pressure of a fuel tank, excess liquefied gas fuel can be returned to a fuel tank.

For example, in the configuration including the above-described conventional overflow prevention valve, a manually operated shut-off valve is separately provided so that liquefied gas fuel does not flow out when the engine is not started for a relatively long period of time. Are known. In this configuration, since the main valve is automatically closed when the engine is stopped, there is an advantage that no manual operation is required even when the engine is not driven for a relatively long period of time. In addition, even when a very small leak (leakage that does not activate the overflow prevention valve) occurs from the fuel supply pipe, it is possible to prevent the liquefied gas fuel from gradually leaking while the engine is stopped. obtain.

In the liquefied gas fuel supply device described above, the solenoid valve device is configured such that the casing body communicates with the second gas flow port in front of the main valve, and is opened and closed by position conversion between the open position and the closed position of the main valve. The annular seal member is disposed by caulking from both inside and outside so that the main valve is opposed to the mouth of the circulation opening and closing portion. Thus, a configuration is proposed in which the flow opening / closing port is hermetically closed by pressure-bonding the seal member to the edge of the flow opening / closing port. The flow opening / closing port is opened apart from the main valve by setting the main valve to the open position, and is closed by the main valve by setting the main valve to the closed position.

In such a configuration, since the main valve is closed at the closed position by pressing the annular seal member against the edge of the flow opening / closing port, the flow opening / closing port is reliably and stably closed. Can do. Therefore, the operation and effect of the present invention that occurs when the main valve is in the closed position can be properly achieved. Furthermore, in this configuration, since the flow opening / closing port portion communicating with the second gas flow port is disposed in front of the main valve, a communication passage communicating with the first gas flow port is provided on the side of the main valve. Thus, the pressure by the liquefied gas fuel acts on the main valve from the side. In particular, when the main valve is converted into the closed position while the liquefied gas fuel is being pumped by the fuel supply pump, a relatively large pressure acts on the main valve from the side. Even when such pressure is applied, the annular seal member is arranged by caulking from both the inside and outside, so that it is possible to sufficiently suppress the occurrence of defects such as deformation and to exhibit the sealing performance at the closed position. Can be maintained over a long period of time.

As the seal member, a material made of a polymer material such as rubber or resin can be used. When DME fuel is used, DME rubber or polytetrafluoroethylene can be suitably used. .

As described above, according to the present invention, when the valve opening / closing control means determines that the flow rate in the fuel supply pipe or / and the engine is an abnormal flow rate based on the supply flow rate determination value, the fuel supply pump and the fuel supply pipe are connected. The operation valve of the electromagnetic valve device interposed in the cylinder is controlled to close the open / close narrow flow path, thereby converting the position of the main valve to the closed position, and liquefied gas fuel from the fuel supply pump of the fuel tank to the fuel supply pipe Therefore, the supply of liquefied gas fuel from the fuel tank can be stopped reliably when an abnormality in the flow rate occurs in the fuel supply pipe or / and the engine. obtain. In addition, if the flow rate abnormality does not occur in the fuel supply pipe or / and the engine, the supply of the liquefied gas fuel by the electromagnetic valve device is maintained. For example, even if an excessive differential pressure is generated by a sudden accelerator operation, Since the supply of the liquefied gas fuel is maintained, the malfunction does not occur unlike the configuration including the conventional overflow prevention valve described above. According to this configuration, it is possible to reliably and accurately follow a sudden accelerator operation, and it is possible to stably perform an appropriate engine operation.

Here, the solenoid valve device opens the first gas flow port and allows the liquefied gas fuel to flow in and out from the first gas flow port, and closes the first gas flow port to supply the liquefied gas fuel. In the case of a configuration with a manual valve whose position is changed by manual operation at the closed position where inflow and outflow are impossible, the open / close operation control function based on the flow rate detected by the flow rate detection sensor and the manual valve are manually operated. It has both an opening and closing function by operation, and exhibits high utility. Even when the open / close narrow channel cannot be shielded due to a malfunction of the operating valve, the inflow and out of the liquefied gas fuel from the first gas flow port is ensured by setting the manual valve to the closed position. Can be prevented.

In addition, the solenoid valve device is a valve closing operation in which the position of the main valve is converted by a manual operation into a retracted position where the position of the main valve can be changed between an open position and a closed position and a shield position where the main valve is held in the closed position. In the case of a configuration comprising a member, it has both an opening / closing operation control function based on the flow rate detected by the flow rate detection sensor and an opening / closing function by manually operating the valve closing operation member, Highly useful.

Further, if the pressure in the return pipe detected by the pressure detection sensor provided in the return pipe for returning the excess liquefied gas fuel to the fuel tank is equal to or lower than a preset return pressure threshold, the return pipe and the fuel tank are The operation valve of the electromagnetic valve device interposed in the valve is controlled to close the open / close narrow flow path, thereby converting the position of the main valve to the closed position and preventing the backflow from the fuel tank to the return pipe. In this case, when the pressure in the return pipe becomes smaller than the internal pressure of the fuel tank, backflow from the fuel tank can be reliably prevented.

Further, the valve opening / closing control means performs control to hold the operation valve of the electromagnetic valve device in the non-communication position when the engine stops, and control to hold the operation valve of the electromagnetic valve device in the communication position when the engine starts. In the configuration to be performed, the liquefied gas fuel can be reliably prevented from flowing out from the fuel tank while the engine is stopped. When the engine is being driven, the operation and effect of the present invention described above can be appropriately achieved by controlling the operation of the operation valve based on the flow rate detected by the flow rate detection sensor.

Further, an annular seal member is disposed by caulking from both the inside and outside of the main valve so as to face the mouth of the flow opening / closing port formed in front of the main valve. In the case of a configuration in which the sealing member is crimped to the opening edge of the flow opening / closing port and closed in a sealed state, when the main valve is in the closed position, the flow opening is reliably and stably formed by the main valve. Since it can close, the effect of this invention which produces a main valve as a closed position can be show | played appropriately. Further, since the deformation of the seal member due to the pressure acting from the side of the main valve can be sufficiently suppressed, the effect of closing the flow opening in a closed state at the closed position can be maintained for a long time.

1 is a conceptual diagram illustrating a liquefied gas fuel supply device 1 of Embodiment 1. FIG. It is a side view from the mirror part 2b side of the fuel tank 2 which comprises the liquefied gas fuel supply apparatus 1. FIG. It is the (A) front view and (B) bottom view of the solenoid valve apparatus 11 of Example 1. FIG. 3A is a cross-sectional view taken along line XX and FIG. 3B is a cross-sectional view taken along line YY in FIG. The electromagnetic valve device 11 interposed between the fuel supply pump 36 and the fuel supply pipe 3 schematically illustrates (A) a state in which the main valve 20 is opened and (B) a state in which the main valve 20 is closed. FIG. A state in which the electromagnetic valve device 11 interposed between the fuel tank 2 and the return pipe 4 is (A) the operating valve 30 is opened, and (B) the operating valve 30 is closed and the main valve 20 is opened. FIG. It is the schematic explaining the state which closes the operation valve 30 and the main valve 20 of the solenoid valve apparatus 11 interposed between the fuel tank 2 and the return pipe | tube 4. FIG. FIG. 4 is a schematic view showing a state in which the main valve 20 is held in the closed position by the valve closing operation member 38 of the electromagnetic valve device 11. It is the (A) front view and (B) bottom view of the solenoid valve apparatus 51 of Example 2. FIG. FIG. 9A is a cross-sectional view taken along a line ZZ and a cross-sectional view taken along a line WW. It is the schematic which shows the state which held the manual valve 61 in the open position of the solenoid valve apparatus 51, and the state which held the manual valve 61 in the obstruction | occlusion position (B).

Embodiment 1 of the present invention will be described in detail with reference to the accompanying drawings.
In the first embodiment, the liquefied gas fuel supply device 1 is provided in an automobile provided with an engine 5 driven by DME fuel. As shown in FIG. 1, the liquefied gas fuel supply device 1 is used in a fuel tank 2 for storing DME fuel, a fuel supply pipe 3 for supplying DME fuel from the fuel tank 2 to the engine 5, and the engine 5. And a return pipe 4 for returning the surplus DME fuel that has not been returned to the fuel tank 2. DME fuel is a liquefied gas fuel according to the present invention.

The fuel tank 2 is disposed, for example, at the lower part of the side of the vehicle body of the truck, and is composed of a cylindrical body 2a and hemispherical mirrors 2b joined to openings on both sides of the body 2a. Has been. The fuel tank 2 is fixed to the vehicle by a fixing member (not shown), and a filling device 40 having a filling valve (not shown) that is opened and closed by manual operation is disposed on one mirror portion 2b. Yes. As shown in FIG. 2, the filling device 40 includes a filling valve handle 42 for manually operating the filling valve and a filling port 43 for filling DME fuel from the outside. An overfill prevention valve device (not shown) provided and the filling port 43 are communicated with each other through the filling valve. When filling the fuel tank 2 with DME fuel, a filling gun (not shown) for filling the DME fuel is connected to the filling port 43 and the filling valve handle 42 is manually operated to open the filling valve. Thus, the DME fuel is filled in the fuel tank 2, and when filling is completed, the filling valve is closed and the filling gun is removed. Through such operations, the fuel tank 2 can be filled with DME fuel.

One mirror portion 2b of the fuel tank 2 includes a safety valve 47 for preventing the internal pressure of the fuel tank 2 from exceeding a predetermined upper limit value, and an electromagnetic valve device 11 to which the return pipe 4 is connected. It is arranged. Here, since the same thing as the structure conventionally used can be applied to the safety valve 47, the detail is abbreviate | omitted. The electromagnetic valve device 11 is a main part of the present invention and will be described in detail later.

Furthermore, a liquid level gauge 48 indicating the amount of DME fuel stored in the fuel tank 2 is disposed on the body 2 a of the fuel tank 2. In addition, an electromagnetic valve device 11 connected to a fuel supply pump 36 disposed inside the fuel tank 2 is disposed below the trunk portion 2a. The electromagnetic valve device 11 is connected to the fuel supply pipe 3 described above, and is interposed between the fuel supply pump 36 and the fuel supply pipe 3. Here, the liquid level gauge 48 can be applied with the same configuration as that conventionally used, and therefore the details thereof are omitted. The electromagnetic valve device 11 disposed in the body 2a of the fuel tank 2 has the same configuration as that disposed in the above-described mirror portion 2b, and is a main part of the present invention. To do.

The fuel supply pump 36 is driven and controlled by the fuel supply control device 35 so as to operate according to the accelerator operation. Further, the fuel supply control device 35 also has a function of controlling the operation of the electromagnetic valve device 11 described above, and is input from

pressure detection sensors

9 and 9 provided in the fuel supply pipe 3 and the return pipe 4 respectively. Based on the pressure signal, the

electromagnetic valve devices

11 and 11 disposed on the body 2a and the mirror 2b of the fuel tank 2 are controlled and operated. Here, the

pressure detection sensors

9 and 9 are disposed on the upstream side of the fuel supply pipe 3 and on the downstream side of the return pipe 4. Then, the fuel supply control device 35 performs processing so as to indirectly detect the flow rate of the DME fuel flowing through the fuel supply pipe 3 based on the pressure signal input from the pressure detection sensor 9 disposed in the fuel supply pipe 3. . Furthermore, in the first embodiment, the engine 5 is also provided with a pressure detection sensor 9, and a pressure signal is output from the pressure detection sensor 9 to the fuel supply control device 35. The pressure detection sensor 9 disposed in the engine 5 is disposed immediately before a fuel injection pump (not shown) disposed in the engine 5, and the fuel supply control device 35 detects the pressure detection. Processing is performed so that the flow rate of the DME fuel supplied to the fuel injection pump is indirectly detected by the pressure (pressure signal) input from the sensor 9. In the first embodiment, the

pressure detection sensors

9 and 9 provided in the fuel supply pipe 3 and the engine 5 are the flow rate detection sensors according to the present invention.

The fuel supply control device 35 is constituted by a control system including a central control device CPU, a storage device RAM, a ROM, and the like. The storage device ROM stores programs for controlling the operation of the fuel supply pump 36 and the

electromagnetic valve devices

11 and 11, and each program is executed by the central control unit CPU. The storage device RAM appropriately stores predetermined data related to each program described above, and each data is read or deleted as necessary. The fuel supply control device 35 having the same configuration as that of a conventional computer can be used, and details thereof are omitted. The operation control of the fuel supply pump 36 by the fuel supply control device 35 can be performed in the same manner as in the prior art, and the details thereof are omitted. Further, the operation control of the

electromagnetic valve devices

11 and 11 by the fuel supply control device 35 will be described later according to the main part of the present invention.

Next, the main part of the present invention will be described.
As shown in FIGS. 1 and 2, the electromagnetic valve devices 11 respectively disposed on one mirror part 2b and the body part 2a of the fuel tank 2 are

pedestal parts

7 and 8 provided on the mirror part 2b and the body part 2a, respectively. It is fixed and attached to. As shown in FIGS. 3 and 4, the solenoid valve device 11 includes a casing body 12 fixed to the

pedestals

7 and 8 and an operating valve drive device 31 that is driven and controlled by the fuel supply control device 35. Yes. The operation valve drive device 31 controls the operation of the operation valve 30. In the first embodiment, the operation valve drive device 31 is constituted by a solenoid, and the operation valve 30 is advanced and retracted by a voltage signal input from the fuel supply control device 35. Operate. The operation valve drive device 31 and the operation valve 30 have a function as a so-called electromagnetic valve that is directly driven and controlled. The operating valve driving device 31 constitutes the operating valve driving means according to the present invention.

The casing body 12 of the electromagnetic valve device 11 has a first gas flow port 13 formed so as to face the

pedestal portions

7 and 8, and a second gas flow port 14 communicating with the first gas flow port 13. Is provided. The first gas flow port 13 communicates with a through hole (not shown) formed in each of the

pedestal portions

7 and 8 in a state where the electromagnetic valve device 11 is disposed in the

pedestal portions

7 and 8. And communicates with the fuel supply pump 36 through these through holes. The through holes of the

pedestal portions

7 and 8 are provided with O-rings or the like (not shown) at the hole edges, and with the solenoid valve device 11 attached, the first gas flow port 13 and the through holes Gas leakage is prevented from occurring in between.

As shown in FIGS. 3 and 4, the casing body 12 has a first main flow path 15 having the first gas flow port 13 as an open end to the outside and a second gas flow port 14 having an open end to the outside. The second main flow path 16 is formed, and the main operation region 17 is formed so as to be orthogonal to the first main flow path 15 and the second main flow path 16, respectively. The passage 16 communicates with the main operation region 17. A main valve 20 is slidably disposed in the main operation region 17, and a variable closing region 19 that is partitioned from the second main flow channel 16 in a sealed manner is formed by the main valve 20 (FIG. 5-8).

The second main flow path 16 is provided with a flow opening / closing port 18 that opens to the main operation region 17, and the flow opening / closing port 18 and the main valve 20 are provided to face each other. The main valve 20 slides in the main operation region 17 to a closed position (see FIG. 5B) for closing the flow opening / closing port 18 and an open position (see FIG. 5A) for opening. The position is converted, and the first main channel 15 (first gas flow port 13) and the second main channel 16 (second gas flow port 14) are converted into a communication state and a non-communication state by this position conversion. The main valve 20 is urged toward the closed position by a coiled spring 27 disposed in the main operation area 17 (movable closing area 19). The spring 27 constitutes an urging means according to the present invention.

The main valve 20 is formed with a narrow channel 22 that always communicates the first main channel 15 and the movable closed region 19, and the narrow channel 22 is located at the open position and the closed position. Even if converted, the first main channel 15 and the movable closed region 19 are always in communication (see FIG. 5).

Further, the casing body 12 is formed with an operating region 26 in which the above-described operating valve 30 is advanced and retracted. The closed narrow channel 24 a that communicates the operating region 26 and the movable closed region 19, the operating region 26, and the first operating region 26. A communication narrow channel 24b communicating with the two main channels 16 is formed (see FIG. 5). The communication narrow channel 24b is provided with an opening / closing port 25 that opens to the operating region 26 side, and the operation valve 30 closes the opening / closing port 25 to communicate with the closed narrow channel 24a (movable closing region 19). A non-communication position (see FIG. 5B) that makes the passage 24b (second main flow path 16) non-communication, and a communication position that opens the opening / closing port 25 and makes the communication state (FIG. 5A). And the position change operation is performed. The operation valve 30 is subjected to position conversion operation control between the communication position and the non-communication position by the operation valve drive device 31 described above. Further, the operating valve 30 is formed with a substantially disc-shaped sealing member 32 at its tip, and is highly pressure-tight by being crimped to the opening edge of the opening / closing port 25 of the communication narrow channel 24b at a non-communication position. It can happen. As the seal member 32, a material having high DME resistance such as rubber or polytetrafluoroethylene is used. Further, the operating valve drive device 31 is held at the non-communication position in a state where no voltage signal is input from the fuel supply control device 35 described above, and moves to the communication position when the voltage signal is input. Therefore, the communication position is maintained while the voltage signal is input by the fuel supply control device 35. In this way, the operation valve 30 is accurately and stably controlled by the fuel supply control device 35. The closed narrow channel 24a and the communicating narrow channel 24b communicating with each other via the operation region 26 constitute the open / close narrow channel 24 according to the present invention.

Further, the casing body 12 is provided with a valve closing operation member 38 so as to be movable along the position conversion direction of the main valve 20 in the variable closing region 19 described above. The valve closing operation member 38 moves forward to the flow opening / closing port 18 side of the second main channel 16, thereby moving the main valve 20 into the closed position (see FIG. 8), and the advanced position. It is possible to move backward to the retracted position (see FIG. 5) that enables the main valve 20 to move to the open position. Here, by setting the valve closing operation member 38 to the retracted position, the main valve 20 can be converted into the open position and the closed position without interfering with the main valve 20. The valve closing operation member 38 is connected to an operation handle 39 that protrudes outside the casing body 12, and is moved between the advanced position and the retracted position by manual operation of the operation handle 39. That is, if the valve closing operation member 38 is set to the advanced position by manual operation, the first main flow path 15 (first gas flow port 13) and the second main flow path 16 (second gas flow port 14) are forcibly made non-conductive. The communication state can be maintained. The operation handle 39 is screwed to the casing body 12, and can be moved to the advanced position by rotating in one direction, and moved to the retracted position by rotating in the other direction. Can be made.

The main valve 20 has a bottomed cylindrical shape that opens on one side, and an annular seal member 23 is disposed on the pressure receiving surface 20a facing the flow opening / closing port 18 of the second main flow path 16. ing. More specifically, an annular groove 20b is formed on the pressure receiving surface 20a side of the main valve 20, and the seal member 23 is fitted into the groove 20b, and the inner peripheral end and outer periphery of the groove 20b. The sealing member 23 is fixed by crimping the end. The seal member 23 is provided so as to face the mouth edge 18a of the above-described flow opening / closing port portion 18, and by setting the main valve 20 to the closed position, the seal member 23 and the mouth edge 18a of the flow opening / closing port portion 18 are sealed. The member 23 is in pressure contact with the flow opening / closing port 18 (see FIG. 5B). In the first embodiment, the mouth edge 18a of the flow opening / closing port 18 is formed in a shape that protrudes in the circumferential direction toward the main valve 20 side, and is sealed at the position where the main valve 20 is closed. It has high pressure-bonding properties with the member 23. The seal member 23 is made of rubber having high DME resistance or a polymer resin made of polytetrafluoroethylene.

The main valve 20 is disposed so as to change its position in a direction substantially orthogonal to the first main flow path 15 in the main operation region 17 orthogonal to the first main flow path 15. That is, the pressure of DME fuel flowing from the side of the first main flow path 15 acts on the main valve 20 from the side, and the pressure is compared when the position of the main valve 20 is changed from the open position to the closed position. Acts strongly. The main valve 20 of the first embodiment can sufficiently suppress the deformation in the radial direction of the above-described polymer resin-made seal member 23 even if such pressure from the side is repeatedly received. This is because the annular seal member 23 is fixed by caulking.

Furthermore, in the electromagnetic valve device 11, the closed narrow channel 24 a and the connecting narrow channel 24 b disposed in the casing body 12 are smaller in channel area than the first main channel 15 and the second main channel 16. It is formed to become. Further, the narrow channel 22 formed in the main valve 20 is formed to have the same channel area or a smaller channel area than the closed narrow channel 24a and the connecting narrow channel 24b.

As described above, such a solenoid valve device 11 is fixed to the

pedestals

7 and 8 provided in the fuel tank 2. Then, the above-described fuel supply pipe 3 is connected to the second gas flow port 14 of the electromagnetic valve device 11 attached to the pedestal portion 7 provided in the trunk portion 2a of the fuel tank 2, and the fuel supply pipe 3 The fuel supply pump 36 disposed in the fuel tank 2 is connected via the electromagnetic valve device 11. On the other hand, the return pipe 4 is connected to the second gas flow port 14 of the electromagnetic valve device 11 attached to the pedestal part 8 provided in the mirror part 2b of the fuel tank 2, and the return pipe 4 and the fuel The inside of the tank 2 is connected via the electromagnetic valve device 11.

The

electromagnetic valve devices

11 and 11 are controlled by the fuel supply control device 35 as described above. A pressure detection sensor 9 disposed in the fuel supply pipe 3, a pressure detection sensor 9 disposed in the engine 5, and a pressure detection sensor 9 disposed in the return pipe 4 are connected to the fuel supply control device 35. (See FIG. 1). And the pressure signal input from each pressure detection sensor 9 is each determined, and control which operates the

solenoid valve apparatus

11 and 11 suitably according to this determination is performed. The fuel supply control device 35 stores a control program and data for controlling the operation of the

electromagnetic valve devices

11 and 11 in its storage device ROM, and is read by the central control device CPU as necessary. And execute.

As described above, the electromagnetic valve device 11 of the first embodiment is manually operated with the operation valve 30 that is controlled by the fuel supply control device 35, the main valve 20 that changes the position according to the operation of the operation valve 30, and the operation valve 30. The valve closing operation member 38 is integrally arranged on the casing body 12.

The operation mode of the liquefied gas fuel supply device 1 provided with such

electromagnetic valve devices

11 and 11 will be described with reference to FIGS. First, as the operation of the electromagnetic valve device 11 connected to the fuel supply pipe 3, when the engine is stopped, the voltage signal from the fuel supply control device 35 is not output to the operation valve drive device 31, As shown in FIG. 5B, the operation valve 30 is held in the non-communication position, and the internal pressure of the fuel tank 2 is higher than the internal pressure of the fuel supply pipe 3, so that the main valve 20 is held in the closed position. . Here, it is assumed that the valve closing operation member 38 is held at the retracted position. When the engine is driven, a voltage signal is continuously output from the fuel supply control device 35 to the operation valve drive device 31, whereby the operation valve 30 is moved to the communication position as shown in FIG. The region 19 and the second main channel 16 communicate with each other. As a result, the pressure difference between the first main flow path 15 (and the variable closing region 19) and the second main flow path 16 is eliminated, and the pressure acting on the pressure receiving surface 20a of the main valve 20 is greater than the biasing force of the spring 27. Thus, the position of the main valve 20 is changed from the closed position to the open position. As described above, during operation of the engine, by setting the operation valve 30 to the communication position, the main valve 20 is maintained in the open position, the flow opening / closing port 18 of the second main flow path 16 is opened, and the first main flow The channel 15 and the second main channel 16 communicate with each other. During operation of the engine, the fuel supply pump 36 operates and is controlled by the fuel supply control device 35, so that the DME fuel pumped at a predetermined flow rate by the fuel supply pump 36 passes through the electromagnetic valve device 11. The fuel flows to the fuel supply pipe 3 and is supplied to the engine 5.

The fuel supply control device 35 detects the pressure in the fuel supply pipe 3 by the pressure detection sensor 9 disposed in the fuel supply pipe 3, and indirectly determines the flow rate of the DME fuel flowing in the fuel supply pipe 3 by the pressure. Detect. Similarly, the flow rate of DME fuel supplied to a fuel injection pump (not shown) of the engine 5 is indirectly detected by a pressure detection sensor 9 disposed in the engine 5. That is, the pressure signal input from these

pressure detection sensors

9, 9 is determined based on a supply flow rate determination value that is set in advance so as to correspond to the pressure signal. Here, the supply flow rate determination value is set, for example, to determine that the DME fuel flowing from the fuel supply tank 2 has an abnormal flow rate when the fuel supply pipe 3 is damaged and gas leaks. In addition, it is possible to determine a case where the flow rate supplied to the engine 5 is significantly reduced compared to the flow rate pumped by the fuel supply pump 36. In this case, the flow rate of the fuel supply pipe 3 is significantly increased or decreased as compared with the flow rate of the fuel supply pump 36. The supply flow rate determination value for determining such a flow rate abnormality includes a minimum pressure value for determining a pressure drop caused by an increase or decrease in the flow rate of the fuel supply pipe 3 and a pressure drop caused by a flow rate decrease to the engine 5. Is set in advance. That is, when the pressure signal input from each

pressure detection sensor

9, 9 is equal to or less than the supply flow rate determination value (the above-mentioned minimum pressure value), the DME fuel flow rate abnormality (supply abnormality) occurs due to gas leakage. It is determined that In the first embodiment, a supply flow rate determination value for determining a flow rate abnormality based on a pressure signal input from a pressure detection sensor 9 provided in the fuel supply pipe 3 and a pressure detection provided in the engine 5 are used. A supply flow rate determination value for determining a flow rate abnormality based on a pressure signal input from the sensor 9 is set as a different determination value, and whether the fuel supply pipe 3 and the engine 5 have an appropriate flow rate or not. The process of determining whether or not is performed separately.

While the engine 5 is being driven, the fuel supply control device 35 receives the pressure signals input from the fuel supply pipe 3 and the

pressure detection sensors

9 and 9 of the engine 5 as the respective supply flow rate determination values (minimum lower limit). Pressure value) or less, and if it is determined that at least one of them is less than or equal to the supply flow rate determination value, a voltage signal to the actuation valve drive device 31 of the electromagnetic valve device 11 connected to the fuel supply pipe 3 Control to stop the output of. As a result, in the electromagnetic valve device 11, as shown in FIG. 5B, the operation valve 30 performs a position conversion operation from the communication position to the non-communication position, so that the variable closed region 19 and the second main channel 16 are not in communication. State. The DME fuel fed to the first main flow path 15 passes through the narrow flow path 22 of the main valve 20 and accumulates in the variable closed area 19, whereby the pressure in the variable closed area 19 increases, The valve 20 moves to the closed position, and the first main channel 15 and the second main channel 16 are brought into a non-communication state. As described above, when the pressure in the fuel supply pipe 3 and / or the pressure in the engine 5 is equal to or lower than a predetermined supply flow rate determination value, it is determined that an abnormality has occurred in the supply of DME fuel, and the main valve 20 is turned on. The DME fuel supply to the fuel supply pipe 3 is forcibly stopped by closing. As a result, if a gas leak occurs due to damage to the fuel supply pipe 3 or the like, the solenoid valve device 11 can be controlled to stop the supply of DME fuel, thereby preventing the gas leak.

Here, in the first embodiment, as described above, the

pressure detection sensors

9, 9 are provided in the fuel supply pipe 3 and the engine 5, respectively, and the gas leakage is determined based on the pressure signals detected by each. Like to do. This is because if the gas leakage is relatively small, the flow rate abnormality (supplied flow rate determination value or less) is accurately determined only by the pressure signal detected by the pressure detection sensor 9 disposed on the upstream side of the fuel supply pipe 3. This is because there are concerns about difficulties. Then, as in the first embodiment, the pressure detection sensor 9 is disposed immediately before the fuel injection pump (not shown) of the engine 5, and at least one of the flow rate abnormality is determined, thereby ensuring gas leakage. And it is easy to judge stably.

Further, when the engine 5 is stopped, the fuel supply control device 35 stops the output of the voltage signal to the operation valve drive device 31 of the electromagnetic valve device 11 connected to the fuel supply pipe 3. As a result, similarly to the case where the pressure signal becomes equal to or less than the supply flow rate determination value, the main valve 20 is converted into the closed position, and the fuel supply pipe 3 and the fuel supply pump 36 are disconnected (FIG. 5B )reference). In this way, while the engine 5 is stopped, the supply of DME fuel from the fuel tank 2 to the engine 5 is reliably stopped. Thereby, for example, even when a gas leak occurs due to damage to the fuel supply pipe 3 or the like while the engine 5 is stopped, gas outflow from the fuel tank 2 can be reliably prevented.

On the other hand, as the operation of the electromagnetic valve device 11 connected to the return pipe 4, while the engine 5 is stopped, the fuel supply control device 35 supplies a voltage signal to the operation valve drive device 31 of the electromagnetic valve device 11 as described above. Is not output, the operating valve 30 is held in the non-communication position, and the internal pressure of the fuel tank 2 acts on the variable closing region 19, so that the main valve 20 is maintained in the closed position (see FIG. 7). In this state, the DME fuel from the fuel tank 2 to the return pipe 4 does not flow backward.

When the engine 5 is driven, the fuel supply control device 35 outputs a voltage signal to the operation valve drive device 31 and moves the operation valve 30 to the communication position, similarly to the electromagnetic valve device 11 connected to the fuel supply pipe 3. When the DME fuel returns from the engine 5 through the return pipe 4, the pressure acts on the pressure receiving surface 20a of the main valve 20, and the main valve 20 moves from the closed position to the open position as shown in FIG. Convert position. Thereby, surplus DME fuel returns from the engine 5 into the fuel tank 2.

In addition, even if the engine 5 is driven, if the pressure signal input from the pressure detection sensor 9 disposed in the return pipe 4 is equal to or less than a preset return pressure threshold, a voltage signal is sent to the operating valve drive device 31. Without output, the operating valve 30 is maintained in the non-communication position (see FIG. 7). This is because it is determined that the pressure in the return pipe 4 may be lower than the internal pressure of the fuel tank 2. That is, if the pressure in the return pipe 4 is larger than the pressure in the fuel tank 2 while the operating valve 30 is maintained at the non-communication position, the internal pressure in the variable closing region 19 communicating with the fuel tank 2 is increased. In contrast, since the pressure acting on the pressure receiving surface 20a of the main valve 20 is increased, the main valve 20 is pressed toward the open position as shown in FIG. 16 communicates. As a result, DME fuel can be returned from the return pipe 4 to the fuel tank 2, and the internal pressure of the fuel tank 2 is greater than the pressure in the return pipe 4, so that backflow from the fuel tank 2 can be prevented. On the other hand, if the pressure in the return pipe 4 is smaller than the pressure in the fuel tank 2 while the operating valve 30 is maintained at the non-communication position, the internal pressure in the variable closing region 19 communicating with the fuel tank 2 is increased. Since the pressure is larger than the pressure acting on the pressure receiving surface 20a of the main valve 20, the main valve 20 is in the closed position as shown in FIG. Thereby, since the 1st main flow path 15 and the 2nd main flow path 16 become a non-communication, the backflow from the fuel tank 2 can be prevented.

Here, the return pressure threshold value set as a condition for performing the position conversion operation of the operation valve 30 between the communication position and the non-communication position is in the first embodiment, and compared with the maximum value of the internal pressure of the fuel tank 2. Is set as a slightly high pressure value. Thereby, when the pressure signal input from the pressure detection sensor 9 disposed in the return pipe 4 is larger than the return pressure threshold, the pressure in the return pipe 4 is surely higher than the internal pressure of the fuel tank 2. If it is less than the return pressure threshold, it is determined that the pressure in the return pipe 4 may be lower than the internal pressure of the fuel tank 2 as described above. And according to such determination, control which performs the position conversion operation of the operation valve 30 is performed. Note that if a gas leak is caused by breakage of the return pipe 4 or the like, the flow rate of the DME fuel returning to the fuel tank 2 is small, so that the return pressure threshold is not exceeded.

When the engine 5 is being driven and the pressure signal input from the pressure detection sensor 9 disposed in the return pipe 4 exceeds the return pressure threshold, the fuel supply control device 35 drives the operating valve as described above. By continuously outputting the voltage signal to the device 31, the main valve 20 is maintained in the open position so that excess DME fuel returns from the return pipe 4 to the fuel tank 2 (see FIG. 6A). . Further, when it is determined that the pressure signal input from the pressure detection sensor 9 of the return pipe 4 is equal to or lower than the return pressure threshold in the state where the main valve 20 of the electromagnetic valve device 11 connected to the return pipe 4 is in the open position, as described above. As described above, the voltage signal to the operation valve drive device 31 of the electromagnetic valve device 11 is stopped, and the operation valve 30 performs the position conversion operation to the non-communication position. When the pressure in the return pipe 4 is larger than the pressure in the fuel tank 2 as described above with the operation valve 30 maintained at the non-communication position, the main valve 20 is pressed toward the open position. In this state, the first main flow path 15 and the second main flow path 16 communicate with each other, and the DME fuel that has returned through the return pipe 4 returns to the fuel tank 2, and no backflow from the fuel tank 2 occurs. (See FIG. 6B). Further, as described above, when the pressure in the return pipe 4 is smaller than the pressure in the fuel tank 2, the main valve 20 is in the closed position, and backflow from the fuel tank 2 can be prevented. Thus, in the state where the operation valve 30 is maintained at the non-communication position, the main valve 20 is opened and closed by increasing or decreasing the internal pressure of the return pipe 4 by the DME fuel returning from the return pipe 4 (FIG. 6). (See (B) and FIG. 7), returning the DME fuel and preventing backflow can occur as appropriate.

Further, when the engine is stopped, the fuel supply control device 35 stops the voltage signal to the operation valve drive device 31 of the electromagnetic valve device 11 connected to the return pipe 4 and the operation valve 30 is held at the non-communication position. While the engine is stopped, the pressure in the return pipe 4 becomes smaller than the internal pressure in the fuel tank 2, so the main valve 20 is held in the closed position and the fuel tank 2 and the return pipe 4 are not in communication with each other. Maintain (see FIG. 7). Thereby, it is possible to prevent the DME fuel in the fuel tank 2 from leaking due to damage or the like occurring in the return pipe 4.

On the other hand, each electromagnetic valve device 11 described above includes a valve closing operation member 38 capable of forcibly holding the main valve 20 in the closed position by manual operation. Therefore, when the liquefied gas fuel supply device 1 is maintained, when the fuel tank 2 is removed, or when it is not used for a long period of time, the operation handle 39 is manually operated to move the valve closing operation member 38 to the advanced position. By doing so, the main valve 20 can be held in its closed position as shown in FIG. Thus, no gas leaks from the fuel tank 2 through each electromagnetic valve device 11 during the period when the use is stopped. As described above, the solenoid valve device 11 according to the first embodiment has a function by manual operation in addition to the control function by the fuel supply control device 35, and thus exhibits excellent usability. .

As described above, the liquefied gas fuel supply apparatus 1 according to the first embodiment controls the operation of the electromagnetic valve device 11 connected to the fuel supply pipe 3 by the fuel supply control apparatus 35, so that the fuel supply pipe 3 and the engine are controlled. When an abnormality occurs in the supply of DME fuel at 5, the DME fuel supply is forcibly stopped, so that gas leakage and the like can be reliably and stably prevented. Further, the backflow from the fuel tank 2 can be reliably and stably prevented by controlling the operation of the solenoid valve device 11 connected to the return pipe 4 by the fuel supply control device 35. In the first embodiment, the fuel supply control device 35 constitutes the valve opening / closing control means of the present invention.

The liquefied gas fuel supply device 1 according to the second embodiment of the present invention has a configuration in which an electromagnetic valve device 51 (FIGS. 9 and 10) including a manual valve 61 that opens and closes the first main flow path 15 is disposed in the fuel tank 2. It is. The liquefied gas fuel supply device 1 according to the second embodiment has the same configuration except that each electromagnetic valve device 11 according to the first embodiment is replaced with a solenoid valve device 51.

In the electromagnetic valve device 51 of the second embodiment, as shown in FIGS. 9 to 11, a manual valve 61 that is moved by a manual operation is disposed in the casing body 52. The manual valve 61 advances into the first main flow path 15 to close the first main flow path 15 (FIG. 11B), and retracts from the closed position to open the first main flow path 15. It is possible to move to the opening position (FIG. 11A). Here, the manual valve 61 includes a closing portion 62 that completely closes the first main flow path 15 at the closing position. Thereby, in the closed position, DME fuel does not flow through the first main flow path 15, and the first gas flow port 13 is substantially closed. The manual valve 61 is screwed to the casing body 52, and an operation hole 63 that can be rotated by a hexagon wrench is provided at a terminal portion exposed to the outside of the casing body 52. The manual valve 61 can be moved back and forth between the open position and the closed position by inserting a hexagon wrench into the operation hole 63 and rotating it.

This solenoid valve device 51 is operated by the fuel supply control device 35 with the manual valve 61 held in the open position in the same manner as the solenoid valve device 11 of the first embodiment (see FIGS. 5 and 6). By controlling the operation of 31, the position of the main valve 20 is converted between the open position and the closed position. That is, in the electromagnetic valve device 51 interposed between the fuel supply pump 36 and the fuel supply pipe 3, the main valve 20 is maintained in the closed position by setting the operation valve 30 to the non-communication position by the operation valve driving device 31. Thus, the DME fuel is prevented from flowing from the fuel supply pump 36 to the fuel supply pipe 3. Therefore, as described above, when the flow rate abnormality is determined by the

pressure detection sensors

9 and 9 provided in the fuel supply pipe 3 and the engine 5, the operation valve 30 is controlled to the non-communication position to thereby control the DME fuel. The supply can be forcibly stopped to prevent gas leakage. By maintaining the operating valve 30 in the communication position, the main valve 20 is set in the open position, and DME fuel is supplied from the fuel supply pump 36 to the engine 5 through the fuel supply pipe 3 (see FIG. 11A). .

Further, in the solenoid valve device 51 interposed between the return pipe 4 and the fuel tank 2, the actuation valve 30 is set by the actuation valve drive device 31 as in the solenoid valve device 11 of the first embodiment (see FIG. 7). By setting the non-communication position, the main valve 20 is maintained in the closed position, and the flow of DME fuel between the return pipe 4 and the fuel tank 2 is stopped. That is, as described above, when the flow rate abnormality is determined by the pressure detection sensor 9 provided in the return pipe 4, the supply of the DME fuel is forcibly stopped by controlling the operation valve 30 to the non-communication position. The backflow from the fuel rank 2 to the return pipe 4 can be prevented. It should be noted that the DME fuel can be returned from the return pipe 4 to the fuel tank 2 with the main valve 20 in the open position by maintaining the operation valve 30 in the communication position.

Further, in any one of the

electromagnetic valve devices

51, 51, when the engine 5 is stopped, the main valve 20 is maintained in the closed position by maintaining the operating valve 30 in the non-communication position. Is stopped, and fuel return from the engine 5 to the fuel tank 2 is stopped.

Thus, even in the configuration of the second embodiment, the same operation and effect as the configuration of the first embodiment described above can be achieved by driving and controlling the operation valve drive device 31.

Further, in the configuration of the second embodiment, the manual valve 61 described above is set to the closed position, so that the first operation is performed regardless of the drive control of the actuation valve 30 (and the position of the main valve 20) by the actuation valve drive device 31. By closing the one gas flow port 13, the inflow and outflow of DME fuel from the first gas flow port 13 can be reliably and stably prevented. Here, when the operation valve 30 malfunctions or the operation valve 30 is damaged, for example, as shown in FIG. 11, the operation valve 30 cannot be converted into the non-communication position, and the open / close narrow channel 24 cannot be closed. Can be a friend. Even in such a state, in the configuration of the second embodiment, by setting the manual valve 61 to the closed position as shown in FIG. Are not communicated, and the inflow and outflow of DME fuel from the first gas flow port 13 can be reliably prevented. Therefore, the gas leakage that may occur due to the malfunction (operation failure or damage) of the operation valve 30 as described above can be reliably prevented by setting the manual valve 61 to the closed position. Similarly to the first embodiment described above, when the liquefied gas fuel supply device 1 is maintained, when the fuel tank 2 is removed, or when it is not used for a long period of time, the manual valve 61 is held in the closed position. Therefore, no gas leaks from the fuel tank 2 through each solenoid valve device 51 during the period when the use is stopped.

The solenoid valve device 51 of the second embodiment has the same configuration as that of the first embodiment described above except that the valve closing operation member 38 of the first embodiment is not provided and the manual valve 61 is provided. Elements are denoted by the same reference numerals and description thereof is omitted.

On the other hand, in the liquefied gas fuel supply device 1 of the first and second embodiments described above, the

electromagnetic valve devices

11 and 51 are configured to be interposed between the return pipe 4 and the fuel tank 2, Instead of the

electromagnetic valve devices

11 and 51, a check valve may be provided. Even in such a configuration, the above-described operational effects of the present invention by the

electromagnetic valve devices

11 and 51 connected to the fuel supply pipe 3 can be appropriately achieved. As this check valve, one having a conventionally used configuration can be applied.

In the first and second embodiments described above, the

pressure detection sensors

9 and 9 are respectively provided with the

solenoid valve devices

11 and 51 connected to the fuel supply pipe 3 in the fuel supply pipe 3 and the engine 5, respectively. The operation is controlled according to the detected pressure signal. However, as another configuration, the pressure detection sensor 9 is disposed only in one of the fuel supply pipe 3 and the engine 5, and the pressure detection sensor 9 The operation may be controlled based on the pressure signal from

In the first and second embodiments, the pressures detected by the

pressure detection sensors

9 and 9 provided in the fuel supply pipe 3 and the engine 5 are respectively detected by the

solenoid valve devices

11 and 51 connected to the fuel supply pipe 3. Although the configuration is such that the operation is controlled according to the signal, as another configuration, a flow rate detection sensor (flow meter) may be provided, and the electromagnetic valve device may be controlled according to the detected flow rate signal.

In the first and second embodiments, the main valve 20 is formed with a narrow channel 22 that always communicates with the first main channel 15 and the variable closed region 19. You may form in a casing body. Even in this configuration, the same operational effects as those of the first and second embodiments described above can be obtained.

In addition, the electromagnetic valve device 11 according to the first embodiment described above has a function of controlling the operation of the operating valve 30 and a function of manually operating the valve closing operation member 38. It can also be used for applications. Even when this solenoid valve device is used for other purposes, the position of the main valve is converted into an open position and a closed position by controlling the actuation valve drive control device of the solenoid valve device based on a predetermined condition. can do. As such an electromagnetic valve device, “a casing body provided with a first gas flow port and a second gas flow port through which liquefied gas fuel can flow in and out;
The second gas flow port is disposed behind the second gas flow port in the casing to form a variable closed region that is partitioned from the second gas flow port side, and the first gas flow port and the second gas flow port A main valve that changes position between an open position for communication and a closed position for closing;
Biasing means for biasing the main valve toward the closed position;
A narrow channel provided in the casing and always communicating the variable closed area and the first gas flow port;
An open / close narrow channel provided in the casing and communicating with the variable closed region and the second gas flow port;
An actuation valve that opens and closes the open / close narrow channel to communicate between the variable closed region and the second gas flow port and a non-communication position that shields the open / close narrow channel;
An actuating valve drive means for converting the position of the actuating valve between a communication position and a non-communication position;
Provided with a retracting position that allows the main valve to be converted into an open position and a closed position, and a valve closing operation member that is converted in position by a manual operation at a shielding position where the main valve is closed. When the condition is met, the actuation valve driving means is driven and controlled so that the position of the actuation valve is converted to the communication position or non-communication ”.

Moreover, even if it exists in the solenoid valve apparatus 51 of Example 2 mentioned above, it can be used for another use. As such an electromagnetic valve device, “a casing body provided with a first gas flow port and a second gas flow port through which liquefied gas fuel can flow in and out;
The second gas flow port is disposed behind the second gas flow port in the casing to form a variable closed area that is partitioned from the second gas flow port side, and the first gas flow port and the second gas flow port A main valve that changes position between an open position for communication and a closed position for closing;
Biasing means for biasing the main valve toward the closed position;
A narrow channel provided in the casing and always communicating the variable closed area and the first gas flow port;
An open / close narrow channel provided in the casing and communicating with the variable closed region and the second gas flow port;
An actuation valve that opens and closes the open / close narrow channel to communicate between the variable closed region and the second gas flow port, and a non-communication position that shields the open / close narrow channel;
An actuating valve drive means for converting the position of the actuating valve between a communication position and a non-communication position;
An open position that allows the liquefied gas fuel to flow in and out from the first gas flow port, and a closed position that closes the first gas flow port and prevents the liquefied gas fuel from flowing in and out. In addition, a manual valve whose position is converted by manual operation is provided, and when a predetermined operating condition is reached, the operating valve driving means is driven and controlled to convert the position of the operating valve to a communication position or a non-communication position. There is a configuration.

The present invention is not limited to the above-described embodiments, and can be appropriately used within the scope of the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 liquefied gas fuel supply apparatus 2 fuel tank 3 fuel supply pipe 4 return pipe 5 engine 9 pressure detection sensor (flow rate detection sensor)
DESCRIPTION OF

SYMBOLS

11,51

Electromagnetic valve apparatus

12,52 Casing body 13 1st gas flow port 14 2nd gas flow port 18 Flow opening / closing port part 19 Variable closing area 20 Main valve 22 Narrow flow path 23 Seal member 24 Open / close small flow path 27 Spring (biasing) means)
30 Actuated valve 31 Actuated valve drive device (actuated valve drive means)
35 Fuel supply control device 36 Fuel supply pump 38 Valve closing operation member 61 Manual valve

Claims

A fuel tank that stores liquefied gas fuel supplied to the engine, a fuel supply pump that is disposed in the fuel tank and pumps the liquefied gas fuel in the fuel tank at a predetermined flow rate, and a liquefaction pumped by the fuel feed pump In a liquefied gas fuel supply device comprising a fuel supply pipe for supplying gas fuel to an engine,
A casing body provided with a first gas outlet and a second gas outlet through which liquefied gas fuel can flow in and out;
An open position that is disposed within the casing body, forms a variable closed region that is hermetically partitioned from the second gas flow port, and communicates the first gas flow port and the second gas flow port, and the closed closure A main valve that converts position to position,
Biasing means for biasing the main valve toward the closed position;
A narrow channel provided in the casing and always communicating the variable closed area and the first gas flow port;
An open / close narrow channel provided in the casing and communicating with the variable closed region and the second gas flow port;
An actuation valve that opens and closes the open / close narrow channel to communicate between the variable closed region and the second gas flow port and a non-communication position that shields the open / close narrow channel;
An electromagnetic valve device comprising an actuating valve driving means for performing a position conversion operation of the actuating valve between a communication position and a non-communication position,
Interposed between the fuel supply pump and the fuel supply pipe so that the first gas flow port is on the fuel supply pump side and the second gas flow port is on the fuel supply pipe side;
A flow rate detection sensor provided in advance in the fuel supply pipe and / or the engine during driving of the engine, in which a supply flow rate judgment value for judging an abnormal flow rate of the liquefied gas fuel supplied to the engine via the fuel supply pipe is set When the flow rate of the liquefied gas fuel detected by the step is determined to be an abnormal flow rate based on the supply flow rate determination value, the operating valve driving means is driven so that the operating valve of the electromagnetic valve device is in a non-communication position. It is characterized by comprising valve opening / closing control means for controlling to stop the supply of the liquefied gas fuel from the fuel supply pump to the fuel supply pipe by controlling the position of the main valve to the closed position by controlling. A liquefied gas fuel supply device.
The solenoid valve device opens the first gas flow port and allows the liquefied gas fuel to flow in and out from the first gas flow port, and the liquefied gas fuel cannot flow in and out by closing the first gas flow port. The liquefied gas fuel supply device according to claim 1, further comprising a manual valve whose position is converted by a manual operation at the closed position.
A solenoid valve device is provided with a valve closing operation member that is manually converted into a retracted position in which the position of the main valve can be changed between an open position and a closed position and a shield position in which the main valve is held in the closed position. The liquefied gas fuel supply device according to claim 1, wherein the liquefied gas fuel supply device is provided.
A return pipe for returning surplus liquefied gas fuel from the engine to the fuel tank,
The solenoid valve device is interposed between the fuel tank and the return pipe so that the first gas flow port is on the fuel tank side and the second gas flow port is on the return pipe side,
The valve opening / closing control means operates the operating valve of the electromagnetic valve device when the pressure in the return pipe detected by the pressure detection sensor disposed in the return pipe becomes less than a preset return pressure threshold during driving of the engine. By controlling the drive of the actuating valve drive means so that the non-communication position is set to the non-communication position, the main valve is converted to the closed position so as to prevent the backflow of liquefied gas fuel from the fuel tank to the return pipe. The liquefied gas fuel supply device according to any one of claims 1 to 3, wherein the liquefied gas fuel supply device is provided.
The valve opening / closing control means
When the engine is stopped, the actuation valve drive means is driven and controlled so as to hold the actuation valve of the solenoid valve device in the non-communication position,
5. The drive valve driving means is controlled so as to hold the operating valve of the electromagnetic valve device in the communication position when the engine is started. 5. The liquefied gas fuel supply device according to Item.
Solenoid valve device
The casing body is provided with a flow opening / closing port portion that communicates with the second gas flow port in front of the main valve and is opened / closed by position conversion to an open position and a closed position of the main valve,
An annular seal member is disposed by caulking from both inside and outside so that the main valve faces the edge of the flow opening / closing port, and in the closed position, the seal member is connected to the port of the flow opening / closing port. The liquefied gas fuel supply device according to any one of claims 1 to 5, wherein the flow opening / closing port is closed in a sealed manner by crimping to an edge.