JP2875180B2 - Electromagnetic pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic pump having a function of supplying cleaning air for removing a tar component attached to a vaporizer or a combustion nozzle of a combustion apparatus.

[0002]

2. Description of the Related Art An electromagnetic pump is used to guide a liquid fuel in a fuel tank attached to a combustion device such as a stove into a combustion chamber such as a stove at a predetermined flow rate. Pump body, an electromagnetic coil provided around the pump body, a terminal plate for relaying power supply to the electromagnetic coil, and a yoke formed of a U-shaped magnetic member forming an annular magnetic path of the electromagnetic coil. It has a basic configuration provided.

[0003] The pump body has a fuel suction portion at the lower portion, which is immersed in liquid fuel in the fuel tank, and a fuel discharge portion at the top portion. The pump body is supplied to the electromagnetic coil through the terminal plate. The pulse excitation current causes the plunger incorporated in the pump body to move up and down, so that the plunger moves up and down to draw liquid fuel from the fuel suction part and discharge it from the top fuel discharge part. The discharged liquid fuel is heated and vaporized by a vaporizer provided at an appropriate position in the combustion device, becomes a vaporized fuel, passes through a fuel supply pipe, and is injected and supplied to a combustion chamber from a nozzle provided at the tip of the pipe. .

In the above-mentioned conventional combustion apparatus, tars formed by condensation of heavy components of the vaporized fuel are deposited on the inside of the vaporizer and on the inner wall surface of the fuel supply pipe downstream of the vaporizer. Since the pipes become narrower due to the accumulation, a so-called cleaning process for appropriately removing the deposits of the tars is performed. As such a cleaning process, JP-A-1-219405 and JP-A-4-3566.
No. 10 has been proposed.

[0005] In the cleaning process described in Japanese Patent Application Laid-Open No. 4-356610, an electric heater in a carburetor is used in a state where the liquid level of the liquid fuel in the fuel tank is positioned lower than the fuel suction port of the pump. Energize and drive the pump to draw air instead of liquid fuel from the fuel suction port and send it into the carburetor.Then, the suction air is heated by the electric heater in the carburetor to high-temperature air, which is vaporized with this high-temperature air. The tars accumulated in the vessel and the fuel supply line are oxidized and decomposed to remove the accumulation of tars.

In the cleaning process described in Japanese Patent Application Laid-Open No. 1-219405, a mechanism for introducing cleaning air is provided at a fuel suction port below the pump. Instead, the air is sucked, and this air is sent to a fuel supply pipe to remove the accumulation of tars accumulated in the vaporizer and the pipe.

In the cleaning air introducing mechanism, a small-diameter fuel intake cylinder having a lower end opening from the upper part is fitted into the bottomed outer pipe, and the inner peripheral surface of the outer pipe and the fuel intake cylinder are connected to each other. An annular closed space is formed in a gap with the outer diameter of the fuel inlet pipe, and a fuel suction pipe communicating with the closed space and having an opening at a lower end surface is hung down from the upper portion of the outer pipe surface. And an air inlet pipe provided with an intake valve.

With the air introduction pipe positioned above the liquid level, the lower part of the outer cylinder is submerged in the liquid fuel in the fuel tank, and after closing the intake valve, the pump is driven. For example, fuel is sucked into the pump through the fuel suction pipe, the annular closed space between the outer pipe and the fuel suction pipe, and the fuel suction pipe. Further, if the intake valve is opened, the fuel level in the closed space temporarily drops to the liquid level position in the fuel tank due to the opening, so if the pump is driven in this state, first, the closed space The fuel inside the pump is sucked, and the liquid level in the closed space of the fuel drops to the lower end of the fuel suction cylinder. Then, air for cleaning passes through the air introduction pipe and the closed space, and flows from the fuel suction pipe into the pump. And supplied to a vaporizer or the like heated by an electric heater.

[0009]

By the way, in the cleaning method described in Japanese Patent Laid-Open No. 4-356610, the liquid level of the liquid fuel in the fuel tank is lower than the fuel inlet of the pump. In order to perform the cleaning process when the liquid fuel remains in the fuel tank, the remaining liquid fuel can be suctioned using a suction jig such as a spoiler. Has to be sucked out, and such an operation is very troublesome, and has a problem that the surroundings are contaminated by dripping or the like.

In the cleaning system described in Japanese Patent Application Laid-Open No. 1-219405, the liquid level in the closed space between the outer pipe and the fuel suction cylinder is controlled by opening the intake valve. The liquid fuel in the closed space formed between the fuel supply cylinder and the outer pipe and the liquid fuel in the fuel tank are separated from each other. Even if the liquid fuel remains in the fuel tank, if the pump is driven, the fuel in the fuel tank is not sucked by the pump, and the air is sucked through the air supply pipe.

Accordingly, if the cleaning mechanism described in Japanese Patent Application Laid-Open No. 1-219405 is used,
It is not necessary to extract the liquid fuel remaining in the fuel tank as in the case of -356610, but after performing a cleaning process, close the intake valve, drive the pump, and try to suck the liquid fuel again. Then, an air reservoir is formed in the closed space between the outer tube and the fuel suction cylinder, so that air is sucked prior to suction of the liquid fuel, or liquid fuel is sucked while pushing the air away. Therefore, there is a problem that the suction amount of the liquid fuel is not stabilized due to the presence of the air in the sealed state, and the supply amount of the fuel to the burner fluctuates, so that a stable combustion state cannot be obtained.

The present invention solves the above problems,
It is an object of the present invention to provide an electromagnetic pump that can easily perform a cleaning process on a fuel supply path and that can immediately suck liquid fuel in a stable state even after performing a cleaning process. I have.

[0013]

According to another aspect of the present invention, there is provided an electromagnetic pump which is provided in a fuel tank and supplies liquid fuel sucked from a fuel suction port which is submerged in the fuel tank to a combustion section side. The pump includes a container having a portion extending upward so as to surround the fuel suction port, and a reflux means for returning fuel in the container to the fuel tank. A fuel inlet hole formed at a position, an intake hole formed at least above the liquid level, and a fuel discharge hole formed at least above the fuel inlet. Are provided between the fuel inlet hole and the fuel outlet hole.

According to a second aspect of the present invention, in the electromagnetic pump according to the first aspect, the intake hole is formed so as to face the inside of the fuel tank.

According to a third aspect of the present invention, in the electromagnetic pump according to the first or second aspect, the container is a cylindrical first container having the fuel inlet and the inlet, a recirculation means and a fuel discharger. A second container having a cylindrical shape having a hole, wherein the first container and the second container are communicated with each other via a downstream side of the fuel inflow hole.

According to a fourth aspect of the present invention, in the electromagnetic pump according to any one of the first to third aspects, the recirculation means includes an impeller disposed inside the container and a drive for rotating the impeller. Means.

According to a fifth aspect of the present invention, in the electromagnetic pump according to any one of the first to third aspects, the reflux means is constituted by a second electromagnetic pump provided at an intermediate portion of the container. It is characterized by having.

[0018]

According to the electromagnetic pump of the first aspect, since the fuel inflow hole is formed in the liquid submerged portion of the container, the liquid fuel is filled through the fuel inflow hole with the fuel tank filled with the liquid fuel. Is introduced into the container, and the fuel suction port of the electromagnetic pump is in a submerged state. Therefore, by driving the electromagnetic pump in this submerged state, the liquid fuel is sucked from the fuel inlet and discharged toward the combustion section.

Further, when performing the cleaning treatment on the combustion part side, the driving of the electromagnetic pump may be temporarily stopped, or the reflux means provided in the container may be driven while the driving of the electromagnetic pump is continued. Then, the liquid fuel stored in the container is sucked by the reflux means and returned to the fuel tank through the fuel discharge hole. As a result, only a minimum amount of liquid fuel is present in the container, and the fuel inlet of the electromagnetic pump is not immersed in liquid fuel.

In this state, while the drive of the recirculation means and the energization and heating of the carburetor of the combustion device are continued, the electromagnetic pump once stopped is restarted, or the continued drive of the electromagnetic pump is continued as it is. As a result, air is introduced into the container through the intake hole and supplied to the combustion section through the electromagnetic pump. Then, by the supply of air to the vaporizer in a heated state, tar accumulated in the vaporizer and the fuel passage is oxidized and decomposed, and the accumulation of tar disappears.

According to the electromagnetic pump of the second aspect,
Since the intake hole is formed so as to face the inside of the fuel tank, air in the fuel tank is sucked through the intake hole by driving the electromagnetic pump in a state where no liquid fuel exists in the container. .

According to the electromagnetic pump of the third aspect,
The container has a cylindrical first container having the fuel inlet hole and the intake hole, and a cylindrical second container having a recirculation means and a fuel outlet hole.
Since the first container and the second container are communicated with each other via the downstream side of the fuel inflow hole, when the recirculation means is not driven, the first container and the second container are passed through the fuel inflow hole. When the liquid fuel flows into and is stored in the container and the recirculation means is driven, the liquid fuel stored in the two containers is discharged from the fuel discharge holes, and the fuel suction port of the electromagnetic pump is It will not be submerged in liquid fuel.

According to the electromagnetic pump of the fourth aspect,
Since the recirculation means is composed of an impeller disposed inside the container and a driving means for rotating the impeller, the liquid fuel in the container is discharged to the outside by the rotation of the impeller driven by the driving means. .

According to the electromagnetic pump of the fifth aspect,
Since the reflux means is constituted by the second electromagnetic pump provided in the middle part of the container, the liquid fuel in the container is discharged to the outside by the vertical movement of the plunger driven by the electromagnetic pump.

[0025]

FIG. 1 is a partially cutaway perspective view showing a first embodiment of an electromagnetic pump according to the present invention, and shows a state in which the electromagnetic pump is mounted on a fuel tank. FIG. 2 is similar to FIG.
FIG. 3 is a cross-sectional view taken along line AA of FIG. The electromagnetic pump 1 includes a pump unit 2 that sucks and discharges the liquid fuel F in the fuel tank T,
It has a basic configuration including a fuel relay section (container) 7 detachably attached to a lower portion of the pump section 2.

The pump section comprises a cylindrical pump body 20,
An electromagnetic coil portion 3 provided around a cylinder 21 of the pump body 20, a yoke 4 made of a magnetic member constituting a part of an annular magnetic path of the electromagnetic coil portion 3, and an upper end flange of a coil bobbin 31 of the electromagnetic coil portion 3. A terminal portion 5 extending from the portion and a connecting portion 6 for connecting the fuel outlet pipe 62 to the pump body 20 are provided.

An upper end of the pump body 20 is fixedly fitted to a lower end of the cylinder 21, and a lower end of the cylindrical fuel suction portion 2a is immersed in the liquid fuel F filled in the fuel tank T. Is provided. The lower end surface of the fuel suction portion 2a is provided with a fuel suction port 2b in which a mesh member is stretched. Further, a fuel discharge section 8 is provided at an upper portion of the cylinder 21.

The yoke 4 is provided at a substantially central portion of the pump body 20 and comprises a pair of upper and lower horizontal plate portions 41 and 42 parallel to each other and a vertical plate portion 43 formed on one side surface. As shown in FIG. 2, through holes are formed in the center portions of the upper and lower horizontal plate portions 41 and 42, and the cylinder 21 is inserted into these through holes.

The inner diameter of the through holes of the upper and lower horizontal plate portions 41 and 42 is set slightly larger than the outer diameter of the cylinder 21, and the clearance between the through hole of the lower horizontal plate portion 42 and the outer peripheral surface of the cylinder 21 is set. A cylindrical lower magnetic body 92 is fitted into the gap between the through hole of the upper horizontal plate portion 41 and the outer peripheral surface of the cylinder 21 at a predetermined distance from each other.

A flange portion 92a is provided below the lower magnetic body 92, and the fuel suction portion 2a is attached to the lower horizontal plate portion 42 of the yoke 4 in a state where the flange portion 92a is fitted over the fuel suction portion 2a. It is tightly fixed. An annular seal member 92b is provided at a lower end portion of the flange portion 92a so as to seal a gap between a lower end surface of the lower magnetic body 92, an outer peripheral surface of the cylinder 21, and an inner peripheral surface of the fuel suction portion.

On the other hand, an annular flange portion 91a projecting in the radial direction is also provided on the upper portion of the upper magnetic body 91, and the upper magnetic body 91 is fitted into the through hole of the upper horizontal plate portion 41, and the flange portion 91a is fitted. Are locked to the inner peripheral edge of the through hole of the upper horizontal plate portion 41. In this state, the fuel discharge portion 8 is screwed and fastened to a male screw threaded on the upper portion of the cylinder 21, so that the yoke 4 and the upper magnetic body 91 are connected to the bottom surface of the fuel discharge portion 8 via the flange portion 91 a. Are fixed in contact with each other.

In the cylinder 21, the liquid fuel F
A plunger 22 for sucking oil into the pump body 20 is provided so as to be slidable in the vertical direction. The plunger 22 is biased in the vertical direction by coil springs 23 and 24 provided inside the upper and lower sides of the cylinder 21. Is to be stopped at a position where it is balanced. Inside the plunger 22, a check valve 25 for suction made of a ball body and a lower valve spring 26 for urging the check valve 25 for suction toward a closing side which is a suction side are installed.

A discharge check valve 28 is provided above the upper coil spring 23. An upper valve spring 29 for urging the discharge check valve 28 toward the closing side, which is the plunger 22 side, is provided above the discharge check valve 28. Is provided.

The electromagnetic coil section 3 is a cylindrical body which is externally fitted to the upper magnetic body 91 and the lower magnetic body 92 while being sandwiched between the horizontal plate sections 41 and 42 of the yoke 4, and is vertically Non-magnetic bobbin 31 having flange 31b and lower flange 31a, and electromagnetic coil 32 wound around its cylindrical body
It has. A terminal 5 extends from one end of the upper flange 31b. The terminal 5 has an electromagnetic coil 3
2 is connected to a lead J for supplying a pulse-like drive signal.

The terminal 5 is provided with a fixed resistor 51, and the current supplied from the lead wire J is supplied to the electromagnetic coil 32 through the fixed resistor 51. By replacing the fixed resistor 51 and selecting various resistance values, the amplitude of the reciprocating vertical movement of the plunger 22 can be changed, and the discharge amount of the liquid fuel F can be finely adjusted to match the design value. ing.

In the above configuration, when the electromagnetic coil 32 is excited by the pulse drive signal to generate a magnetic flux, the plunger 22 receives a magnetic attraction and receives the upper coil spring 23.
The liquid fuel F in the fuel tank T is sucked from the fuel suction port 2b and discharged from the fuel discharge port 61 at this time. On the other hand, when the magnetic attraction force disappears during the pulse pause period, the plunger 22 is pushed down by the repulsive force of the upper coil spring 23, and when the plunger 22 descends, the liquid fuel F in the fuel suction portion 2a is discharged by the suction check valve 25. Is introduced above the installation section. By repeating this operation, a fixed amount of the liquid fuel F is supplied from the fuel discharge port 61 to a combustion chamber such as a burner.

Next, the fuel relay section 7 will be described in detail with reference to FIGS. The fuel relay section 7 has a bottomed cylindrical suction section surrounding container 71 fitted to the fuel suction section 2 a of the pump section 2, and is adjacent to the suction section surrounding container 71, and is integrally arranged via a partition wall 70. Bottomed cylindrical suction container 72 provided
And fuel delivery means (recirculation means) 73 attached to the suction container 72. In the first embodiment, the container of the present invention is constituted by the suction part surrounding container 71 and the suction container 72.

The suction part surrounding container 71 and the suction container 7
The upper part of the fuel tank 2 is provided with a flange part 74 in which the upper edges of the fuel tank T and the fuel transfer part 7 with the pump part 2 mounted on the mounting opening of the fuel tank T are screwed together. By doing so, the electromagnetic pump 1 is fixed to the fuel tank T.

The inner diameter of the suction portion surrounding container 71 is set slightly larger than the outer diameter of the upper portion of the fuel suction portion 2a.
The fuel suction portion 2a is fitted into the suction portion surrounding container 71 in a sliding state via the ring 74a. Then, according to the tapered shape of the fuel suction section 2a, the fuel suction section 2
a between the outer peripheral surface of a and the inner peripheral surface of the suction portion surrounding container 71,
An annular air introduction passage 75 extending in the up-down direction is formed.

An intake hole 71a for introducing air is formed in the upper part of the suction part surrounding container 71 and above the highest level of the liquid fuel F in the fuel tank T. A small fuel inflow hole 71b is formed in the lower portion of the surrounding container 71, and the liquid fuel F normally flows into the suction portion surrounding container 71 from the fuel inflow hole 71b. A communication hole 71 c for guiding the internal liquid fuel F to the fuel suction container 72 is provided at the bottom of the suction portion surrounding container 71.

On the other hand, a communication hole 72a for receiving the liquid fuel F in the suction portion surrounding container 71 is provided at the bottom of the suction container 72, and the communication hole 72a and the communication hole 71c of the suction portion surrounding container 71 are provided. Are connected by an oil guide tube 76. Further, the suction container 7 is provided above the suction container 72.
2 is provided with a fuel discharge hole 72b for leading the liquid fuel F inside to the outside.

Accordingly, the liquid fuel F flowing from the fuel inflow hole 71b into the suction portion surrounding container 71 is introduced into the suction container 72 through the communication hole 71c, the oil guide tube 76, and the communication hole 72a. The air whose surface has risen is led out of the fuel discharge hole 72b to the outside. As a result, the liquid levels in the suction part surrounding container 71 and the suction container 72 are usually at the same level as the liquid level in the fuel tank T.

The fuel delivery means 73 includes an electric motor (drive means) 73 provided vertically above the suction container 72.
a and a drive shaft 73 suspended from the electric motor 73a.
b, and an impeller 73c provided at the lower end of the drive shaft 73b. And the electric motor 73
The impeller 73c rotates coaxially with the drive shaft 73b around the axis by supplying electric power to a and rotating it.
The liquid fuel F in the suction part surrounding container 71 is sucked into the suction container 72.

In the present invention, the impeller 73 is used.
The electric motor 73a and the impeller 73 are designed such that the fuel suction amount of c is considerably larger than the flow amount of the liquid fuel F flowing into the suction portion surrounding container 71 through the fuel inflow hole 71b.
The ability of c is set.

The operation of the first embodiment will be described below with reference to FIGS. FIG. 3 is a partial cross-sectional explanatory view showing a state in which the electromagnetic pump of the first embodiment performs a normal drive for sucking and discharging liquid fuel, and FIG. FIG. 4 is an explanatory partial cross-sectional view showing a state in which driving during cleaning is performed.

First, during a normal operation in which the pump unit 2 is driven to suck and discharge the liquid fuel F in the fuel tank T,
The driving of the fuel delivery means 73 is stopped. Therefore, as shown in FIG. 3, the liquid fuel F in the fuel tank T flows into the suction portion surrounding container 71 through the fuel inflow hole 71b,
A part thereof is further supplied to the suction container 72 through the oil guide pipe 76, and the liquid level in the suction part surrounding container 71 and the suction container 72 is the same as the liquid level in the fuel tank T.

In this state, when a pulse current is supplied to the electromagnetic coil section 3 to drive the pump section 2, the suction section surrounding container 7
The liquid fuel F in 1 is sucked into the pump main body 20 through the fuel suction part 2 a and discharged to the fuel outlet pipe 62. The liquid fuel F in the suction portion surrounding container 71 for the sucked portion is sequentially replenished from the fuel inflow hole 71b. Therefore, the pump is operated until the liquid fuel F in the fuel tank T reaches a level equal to or lower than the fuel inlet 2b. The suction / discharge of the liquid fuel F by the unit 2 is continued.

Next, when the cleaning process of the combustion device is performed before the liquid fuel F decreases to the level of the fuel inlet 2b, the drive of the pump unit 2 is temporarily stopped, and the electric motor 73a is supplied with electric power. To drive the fuel delivery means 73. Then, the liquid fuel F in the suction portion surrounding container 71 is sucked into the suction container 72 through the oil guide tube 76 by the rotation drive of the impeller 73c, and is pushed up after passing through the impeller 73c, and is pushed up in the fuel discharge hole 72b. And is returned to the fuel tank T.

The suction amount of the fuel delivery means 73 is set to be much higher than the flow rate flowing into the suction portion surrounding container 71 through the fuel inflow hole 71b. The liquid fuel F does not exist except for those sequentially supplied from the fuel inflow hole 71b.
Accordingly, when the liquid fuel F flows into the suction portion surrounding container 71 from the fuel inflow hole 71b, the liquid fuel F is immediately sucked in the form of bubbles in a gas-liquid mixed state by the rotational drive of the impeller 73c. The surrounding container 71 is in an empty state where almost no liquid fuel F exists.

When the pump unit 2 is driven again in this state, the air in the fuel tank T passes through the suction hole 71a and enters the suction portion surrounding container 71 as shown by the dotted arrow in FIG. It is introduced, passes through the pump body 20 via the fuel suction portion 2a, and is supplied to the vaporizer or the fuel line of the combustion device through the fuel outlet pipe 62, and is vaporized in a high temperature state in which the electric heating is continued. The accumulated tars are oxidized and decomposed in the vessel and the fuel line, and as a result, the tars are removed.

In the above embodiment, when cleaning is performed, the driving of the pump unit 2 is temporarily stopped. However, the fuel delivery unit 73 may be driven while the driving of the pump unit 2 is continued. Good. Then, the liquid fuel F is sucked by the pump body 20 until the liquid fuel F in the suction portion surrounding container 71 becomes lower than the level of the fuel suction port 2b by the driving of the fuel delivery means 73, so that the combustion is performed. Although the combustion in the device is continued, the cleaning process is automatically switched from the time when the liquid fuel F in the suction portion surrounding container 71 becomes lower than the level of the fuel suction port 2b.

When the cleaning process is completed,
The driving of the fuel delivery means 73 may be stopped. Then, the liquid fuel F in the fuel tank T is supplied to the fuel inflow hole 71b.
The liquid fuel F is discharged into the fuel outlet pipe 62 by driving the pump unit 2 and is supplied to the combustion device because the inside of the suction part surrounding container 71 and the inside of the suction container 72 are filled through.

Further, in the above embodiment, the fuel discharge hole 72b is provided above the suction container 72 and above the liquid level of the liquid fuel F. However, in the present invention, the fuel discharge hole 72b is provided. It is not limited to being provided above the liquid level, and may be below the liquid level in the fuel tank T as long as it is on the downstream side of the impeller 73c.

According to the present invention, as described in detail above, by driving the fuel delivery means 73 having a large suction capacity provided in the suction container 72, the inside of the suction portion surrounding container 71 in which the fuel suction portion 2a is immersed is provided. The liquid fuel F is forcibly extracted, the suction unit surrounding container 71 is made substantially empty, and air is sent to the combustion device by driving the pump unit 2, so that the initial operation of the cleaning process is quick. This is convenient for performing the cleaning process in a short time.

When the cleaning process is completed, the liquid fuel F is immediately introduced into the suction portion surrounding container 71 through the fuel inflow hole 71b simply by stopping the driving of the fuel delivery means 73. Since the fuel inlet 2b is immersed in the liquid fuel F without passing through the air reservoir,
This realizes stable suction and discharge of the liquid fuel F, which is effective in causing the combustion device to perform normal combustion.

FIG. 5 is a partially cutaway perspective view showing a second embodiment of the electromagnetic pump according to the present invention. As shown in this figure, in the case of the electromagnetic pump 1a of the second embodiment, the oil guide tube 76
Is bent upward so as to be parallel to the suction portion surrounding container 71, and an oil guide pipe 76 is provided at the bent portion.
A suction container 720 having the same diameter as that of the suction container 720 is formed. Then, a second electromagnetic pump 77 is connected to the tip of the suction container 720. In the second embodiment, the electromagnetic pump 77, the suction container 720, and the suction portion surrounding container 7
1 form a fuel relay portion 7a.

The second electromagnetic pump 77 has basically the same configuration as that of the pump unit 2, and reciprocates in the cylinder 77a connected to the upper end of the suction container 720. A moving plunger 77b, a bobbin 77c externally fitted to the cylinder 77a, an electromagnetic coil 77d wound around the bobbin 77c,
and a yoke 77h having a U-shape in cross section made of a magnetic material sandwiching c from above and below. The cylinder 77a projects outward from above and below the yoke 77h.

A spherical check valve 77e is provided in the lower part of the plunger 77b. The check valve 77e is pressed downward by the urging force of a valve spring 77f provided at an upper portion, and the pressing closes the fuel passage in the plunger 77b. Also, the cylinder 77
A pair of support springs 77g are provided inside and above the plunger 77b, and the plunger 77b is stopped at the equilibrium position by the urging force of the pair of support springs 77g. A connection pipe 77i is screwed into a portion of the cylinder 77a projecting upward from the yoke 77h.
The discharge pipe 77j is connected to i. This discharge pipe 77j
Is folded back by approximately 180 °, and its tip is drawn into the fuel tank T. The electromagnetic pump 77 is connected to the suction container 720 in a state where the cylinder 77a projecting downward from the yoke 77h is fitted in a through hole formed in the flange portion 74.

In the second embodiment, the suction portion surrounding container 7
1, the suction container 720, and the discharge pipe 77j form the container of the present invention.

According to the above-described structure of the second embodiment, by supplying a pulse current to the electromagnetic coil 77d, the plunger 77b at the equilibrium position can be used as a pair of upper and lower support springs 77g.
Moves up and down against the urging force of When the fuel moves downward, the discharged fuel flows backward from the constriction hole 77k to the upper part of the plunger 77b. However, since the constriction hole 77k has a small diameter and a large fluid resistance, the upper part of the plunger 77b becomes a negative pressure and the check valve 77b.
e is in the valve open state, the fluid under the plunger 77b is introduced into the plunger 77b, and the valve spring 7
The check valve 77e is closed by the urging force of 7f and the resistance of the fluid on the check valve 77e, and the fluid on the check valve 77e is discharged into the fuel tank T through the connection pipe 77i and the discharge pipe 77j. Will be done.

Accordingly, the electromagnetic pump 7 of the suction container 720 is kept in a state where the driving of the pump unit 2 on the suction part surrounding container 71 side is stopped or the driving of the pump unit 2 is continued.
7, the liquid fuel F introduced into the suction portion surrounding container 71 through the fuel inflow hole 71b is sucked by the vertical reciprocation of the plunger 77b, and is discharged.
The liquid fuel F is returned to the fuel tank T via 7j, and the liquid fuel F does not substantially exist in the suction portion surrounding container 71.

As described above, since the outer dimensions of the suction container 720 can be reduced by using the electromagnetic pump 77 as compared with the case where the impeller 73c is used, the electromagnetic pump 1a can be made more compact accordingly. become.

[0063]

According to the first aspect of the present invention, a container having a portion extending upward so as to surround a fuel suction port of the electromagnetic pump, and a recirculation means for returning fuel in the container to the fuel tank. A fuel inlet hole is provided at a submerged position of the container, an intake hole is provided at least above the liquid level, and a fuel discharge hole is provided at least above the fuel inlet port. Since the liquid fuel is provided between the fuel discharge hole and the discharge hole, the liquid fuel is discharged from the fuel discharge hole by driving the recirculation means, whereby the container can be emptied. By driving the electromagnetic pump in this state, air is sucked from the intake hole, supplied to the high temperature combustion section through the fuel inlet, and accumulated in the carburetor and the fuel passage by the supplied air. A cleaning process for oxidizing and removing tar components can be performed.

As described above, since the liquid fuel in the container is sucked and removed by the recirculation means, the liquid fuel is emptied more quickly than in the conventional case where the liquid fuel is sucked and removed by driving an electromagnetic pump. This is convenient for quickly switching from the combustion state to the cleaning state.

After the cleaning process is completed,
By stopping the driving of the recirculation means, the liquid fuel flows into the container from the fuel inflow hole, and the air reservoir is not formed in the container unlike the conventional case. If the air is trapped, the air is sucked prior to the suction of the liquid fuel due to the presence of the air reservoir, or the fluctuations and instability of the fuel supply amount due to the suction of the liquid fuel while pushing the air away. This is extremely convenient for obtaining stable combustion on the combustion section side.

According to the second aspect of the present invention, the intake hole is formed so as to face the inside of the fuel tank.
By driving the electromagnetic pump in a state where there is no liquid fuel in the container, air in the fuel tank is sucked through the intake hole, and the air in the electromagnetic pump is compared with the case where the intake hole is provided outside the fuel tank. This is effective in suppressing the suction of foreign matter into the device.

Further, at the time of cleaning, there is no need to remove the fuel from the fuel tank, so that automatic cleaning can be performed every time the fire is extinguished, and the vaporizer can always be kept in a normal state.

According to the electromagnetic pump of the third aspect, the container is composed of a cylindrical first container having a fuel inlet and an inlet, and a cylindrical second container having a recirculation means and a fuel outlet. Since the first container and the second container are connected to each other via the downstream side of the fuel inflow hole, the first container and the second container can be disposed in parallel, and This is advantageous in making the electromagnetic pump compact.

According to the fourth aspect of the present invention, since the recirculation means is composed of the impeller disposed inside the container and the driving means for rotating the impeller, the recirculation means has a simple structure. This is effective in inexpensively manufacturing an electromagnetic pump including the reflux means.

According to the electromagnetic pump of the fifth aspect, since the reflux means is constituted by the second electromagnetic pump provided at the intermediate portion of the container, the outer dimensions of the container can be reduced. This is convenient for making the electromagnetic pump including the container compact.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing a first embodiment of an electromagnetic pump according to the present invention.

FIG. 2 is a cross-sectional view taken along line AA of FIG.

FIG. 3 is a partial cross-sectional explanatory view showing a state in which the electromagnetic pump of the first embodiment is performing a normal drive for sucking and discharging liquid fuel.

FIG. 4 is a partial cross-sectional explanatory view showing a state in which the electromagnetic pump of the first embodiment is performing a drive at the time of cleaning for sucking and discharging air.

FIG. 5 is a partially sectional explanatory view showing a second embodiment of the electromagnetic pump according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electromagnetic pump 2 Pump part 20 Pump main body 2a Fuel suction part 21 Cylinder 22 Plunger 23 Upper coil spring 24 Lower coil spring 3 Electromagnetic coil part 31 Coil bobbin 32 Electromagnetic coil 4 Yoke 5 Terminal part 51 Fixed resistor 6 Connection part 61 Fuel outlet 62 Fuel Outlet pipe 7, 7a Fuel junction (container) 70 Partition wall 71 Suction part surrounding container 71a Intake hole 71b Fuel inflow hole 71c Communication hole 72 Suction container 72a Communication hole 72b Fuel discharge hole 73 Fuel delivery means (recirculation means) 73a Electric motor (Drive means) 73b Drive shaft 73c Impeller 74 Flange part 74a O-ring 75 Air introduction passage 76 Oil guide tube 77 Second electromagnetic pump (recirculation means) 8 Fuel discharge part 91 Upper magnetic body 92 Lower magnetic body 91a, 92a Flange part T Fuel tank F Liquid fuel

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Shuichi Hiramatsu 2-7-115 Kita Kamei-cho, Yao-shi, Osaka Inside Silver Co., Ltd. (56) References JP-A-6-147474 (JP, A) JP-A Heisei 3-113207 (JP, A) JP-A-6-147467 (JP, A) JP-A-6-55034 (JP, U) JP-A-6-30628 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F04B 17/04 F23D 11/38 F23N 1/00 105

Claims (5)

(57) [Claims] 1. An electromagnetic pump provided in a fuel tank and for supplying liquid fuel sucked from a fuel suction port facing the inside of the fuel tank and submerged to a combustion section side, extends upward so as to surround the fuel suction port. A container having a bent portion;
A recirculation means for recirculating the fuel in the container into the fuel tank, wherein the container has a fuel inlet formed at a submerged position of the container and at least a position above a liquid level. And at least the fuel intake
An electromagnetic pump having a fuel discharge hole formed above an inlet , wherein the recirculation means is provided between the fuel inlet hole and the fuel discharge hole. 2. The electromagnetic pump according to claim 1, wherein the intake hole is formed so as to face the inside of the fuel tank. 3. The container comprises a cylindrical first container having the fuel inlet and the intake hole, and a cylindrical second container having a recirculation means and a fuel outlet. 3. The electromagnetic pump according to claim 1, wherein the second container communicates with the fuel inlet through a downstream side of the fuel inlet. 4. The recirculation means according to claim 1, wherein the recirculation means comprises an impeller disposed inside the vessel and a driving means for rotating the impeller. Electromagnetic pump. 5. The electromagnetic pump according to claim 1, wherein said reflux means is constituted by a second electromagnetic pump provided at an intermediate portion of said container.