JP2000045933A - Electromagnetic reciprocal pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable sucking and discharging of the high pressure fluid without increasing the sliding resistance of the plunger by sucking and discharging the fluid in the cylinder by reciprocal motion of the plunger with high rigidity, and by storing the fuel that leaks from the sliding surface of the plunger in the storage chamber and flowing it out of the housing through an orifice. SOLUTION: A magnetic body, for instance a plunger 12 made of iron materials is fit into the inside of a cylinder 11 that is fit into the inside of a third housing 4, to constitute an operation chamber 7. At a bottom portion 4a of the third housing 4, a fuel opening passage 15 is provided, serving as an orifice for communicating with a storage chamber M formed by the other end face of the plunger 12 and the bottom portion 4a thereof, in order to return the fuel that leaked from between the cylinder 1 and the plunger 12 directly to the fuel tank. In this structure, use of the plunger 12 with high rigidity to vary the capacity of the operation chamber 7 allows the highly pressured fuel to be supplied. Further, fuel opening passage 15 facilitates the operation of the plunger 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic reciprocating pump for sucking and discharging a fluid by utilizing the exciting action of a coil.

[0002]

2. Description of the Related Art Various pumps are used for pumping a fluid, and among them, there is an electromagnetic drive system having a simple structure. This electromagnetic drive system is roughly classified into a movable coil type and a movable magnet type. However,
In the case of a moving coil pump, when the discharge amount increases, the discharge pressure may suddenly decrease and the pump may become unusable. In general, a movable magnet type pump having a small change in the discharge amount and discharge pressure is used. Have been. For example, there is a diaphragm type pump disclosed in Japanese Patent Application Laid-Open No. 54-84603 as this movable magnet type pump.

[0003]

The movable magnet diaphragm pump disclosed in the above-mentioned publication has a working chamber (pump chamber) for pumping a fluid. The working chamber has a diaphragm as a main component, and the diaphragm keeps airtightness with the outside, for example, a drive unit. However, there is a limit in improving the strength of the diaphragm, and there is a problem that it is difficult to perform high-pressure pumping of the fluid. Accordingly, an object of the present invention is to provide an electromagnetic reciprocating pump capable of high-pressure pumping of a fluid with high reliability.

[0004]

According to the first aspect of the present invention,
An electromagnetic reciprocating pump that sucks and discharges a fluid by using the exciting action of a coil uses a highly rigid plunger to change the volume in a cylinder (pump chamber). For example, since the plunger is reciprocated in the cylinder by the plunger driving means,
Fluid is sucked into the cylinder from the suction port, and the sucked fluid is discharged from the discharge port to the outside of the cylinder.
At this time, the suction and discharge of the fluid is performed by reciprocating motion of the rigid plunger, and the fuel leaked from the sliding surface of the plunger is stored in the storage chamber and is discharged from the outlet to the outside of the housing. The high-pressure fluid can be sucked and discharged without increasing the plunger sliding resistance.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes an electromagnetic reciprocating pump. In this embodiment, a case will be described in which the electromagnetic reciprocating pump 1 is used as a fuel pump in a fuel injection device of an automobile. The electromagnetic reciprocating pump 1 includes a first housing 2 provided with a passage for fuel as a fluid,
The outer shape is composed of a second housing 3 and a third housing 4 which are airtightly connected to the first housing 2.

A concave portion 2a is provided at a portion of the first housing 2 facing the second and third housings 3, 4, and an annular member adapted to the shape of the concave portion 2a is provided in the concave portion 2a. 5 is fitted via a valve member 6. The annular member 5 is formed of a magnetic material, for example, an iron material. A substantially central portion of the annular member 5 is provided with a hole 5a having a step, and the hole 5a constitutes a part of a working chamber 7 for pumping fuel. At substantially the center of the hole 5a, a pedestal 5b that receives one end of a spring 13 described later is located. The first housing 2 has a fuel suction passage 8 for supplying fuel from a fuel supply source (not shown) to a working chamber 7 and a fuel pressure feeding passage for feeding fuel pressurized in the working chamber 7 to fuel injection means (not shown). 9 are provided respectively.

A portion of the valve member 6 corresponding to the opening of the fuel suction passage 8 is provided with a suction valve 6a as first valve means for permitting only the flow of fuel from the fuel suction passage 8 to the inside of the working chamber 7.
(See FIG. 2). A discharge valve 6b as a second valve means for permitting only the flow of fuel from the inside of the working chamber 7 to the fuel pressure transmission path 9 is provided at a position corresponding to the opening of the fuel pressure transmission path 9 of the valve member 6 (FIG. 2). The second housing 3 has a cylindrical shape, and a third housing 4 is provided inside the second housing 3.
Are arranged. The third housing 4 is a substantially cup-shaped cylindrical body made of a magnetic material, for example, an iron material, and is positioned so that an opening thereof faces the working chamber 7. A collar is provided on the periphery of the opening and the periphery of the bottom of the third housing 4, and these flanges are in contact with the inner peripheral surface of the second housing 3, respectively.

A plunger 1 to be described later is provided between the inner surface of the second housing 3 and the outer surface of the third housing 4, that is, the space covered by the inner and outer peripheral surfaces of both housings.
2 is provided. Coil 10
Is connected to a power supply via a not-shown energization control means. A cylindrical cylinder 11 is inserted into the third housing 4, and a plunger 12 made of a magnetic material, for example, an iron material is inserted into the cylinder 11.
Are slidably fitted. One end surface of the plunger 12, that is, an end surface corresponding to the opening of the third housing 4 and the inner surface of the cylinder 11 also constitute a part of the working chamber 7.

Between the annular member 5 and the plunger 12,
A spring 13 for urging the plunger 12 against the bottom 4a of the third housing 4 is provided. The plunger 12 is constantly biased by the spring 13 toward the bottom 4a of the third housing 4. The above-described coil 10 and spring 13
These form a plunger driving means. When the plunger 12 moves toward the bottom 4a between the other end of the plunger 12 and the bottom 4a of the third housing 4, the collision between the other end of the plunger 12 and the bottom 4a of the third housing 4 occurs. Is disposed to alleviate this. Also, on the bottom 4a of the third housing 4,
A fuel release passage 15 is provided as an outlet communicating with a space (reservoir M) formed by the other end surface of the plunger 12 and the bottom 4 a of the third housing 4.
The fuel in the working chamber 7 leaking from between the plunger 1 and the plunger 12 is directly returned to a fuel tank (not shown). For this reason, the operation of the plunger 12 is performed smoothly.

Next, the operation of the above-mentioned electromagnetic reciprocating pump 1 will be described with reference to FIG. Here, the direct current is coil 1
0, when the coil 1 is turned on, as shown in FIG.
By the excitation of 0, the plunger 12 moves upward in the figure against the urging force of the spring 13. When an alternating current is supplied, the plunger moves upward when the driving force by the current becomes larger than the spring urging force. As the plunger 12 moves, the volume of the working chamber 7 decreases, and the fuel pressure in the working chamber 7 increases. The discharge valve 6b is opened by the increase in the fuel pressure, and the pressurized fuel in the working chamber 7 is discharged to the fuel pressure feed path 9 through the discharge valve 6b as shown by an arrow A in the figure.

When the energization of the coil 10 is interrupted by the direct current, the exciting action of the coil 10 is also stopped, and as shown in FIG.
Moves downward in the figure. In the case of the alternating current, when the driving force becomes smaller than the spring urging force due to the current, the plunger 12 moves downward. As the plunger 12 moves, the volume of the working chamber 7 increases, and the fuel pressure in the working chamber 7 decreases. The decrease in the fuel pressure causes the suction valve 6a to open, and fuel is drawn into the working chamber 7 from the fuel suction passage 8 through the suction valve 6a as indicated by an arrow B in the drawing. At this time, the plunger 12 moves toward the bottom 4a of the third housing 4 by the urging force of the spring 13, but the disc spring 14 collides with the bottom 4a of the third housing 4 at the other end of the plunger 12. Is reduced, and the collision noise can be reduced.

By repeatedly performing the control of energizing the coil 10, the fuel suction operation and the fuel discharge operation are repeatedly performed in the working chamber 7, and the pressurized fuel is supplied to the fuel injection means. . Therefore, since the plunger 12 having high rigidity is used to change the volume of the working chamber 7, the fuel pressurized to a high pressure can be pumped. Here, when the fuel pressure of the conventional electromagnetic reciprocating pump using the diaphragm and the fuel pressure of the electromagnetic reciprocating pump 1 using the plunger 12 of the present invention are compared, the conventional electromagnetic reciprocating pump is capable of pumping. Fuel pressure is 0.
On the other hand, in the electromagnetic reciprocating pump 1 of the present invention, the fuel pressure that can be pumped is 0.1 to 0.5 MPa.
The pressure is 10 MPa, and the fuel can be pumped at approximately 20 times the pressure.

The fuel in the working chamber 7 is supplied to the cylinder 11
Through the gap between the inner surface of the plunger 12 and the outer surface of the plunger 12, and leaches between the other end of the plunger 12 and the bottom 4a of the third housing 4. At this time, the plunger 12 is lubricated. Therefore, since the plunger 12 is lubricated by the fuel, seizure of the plunger 12 can be prevented, and there is no need to separately provide a lubrication means for the plunger 12, so that the electromagnetic reciprocating pump 1 can be simplified and the cost can be reduced. Can be reduced. In addition, since the plunger 12 only reciprocates in the cylinder 11, sufficient lubrication can be performed even with a low-lubricity liquid such as fuel. further,
A low-viscosity fluid can also be pumped, and a wide variety of fluids can be pumped.

Next, a second embodiment is shown in FIG. 3, and this embodiment will be described. In the figure, the same members as those shown in FIG. 1 are denoted by the same reference numerals as those used in FIG. 1, and the description thereof will be omitted, and different points will be described. The operation of the electromagnetic reciprocating pump of the second embodiment is a double action, whereas the operation of the electromagnetic reciprocating pump of the first embodiment is a single action. I have. The details will be described below. FIG.
As shown in FIG. 2, the electromagnetic reciprocating pump 20 includes a pair of first and second housings 2 provided with a fuel passage.
The outer shape is constituted by the first and second housings 23 and the third housing 23 sandwiched between the housings 21 and 22 while keeping the airtightness.

The first housing 21 is configured substantially in the same manner as the first housing 2.
A recess 21a into which an annular member 25 forming a part of the working chamber 24 is fitted; a fuel suction passage 21b for supplying fuel from a fuel supply source (not shown) to the working chamber 24;
And a fuel pressure feed path 21c for feeding the fuel pressurized in the above to a fuel injection means (not shown). The second housing 22 is also configured substantially in the same manner as the first housing 2, and the second housing 22 also includes a concave portion 22a in which an annular member 27 forming a part of the working chamber 26 is fitted.
A fuel suction passage 22b for supplying fuel from a fuel supply source (not shown) to the working chamber 26, and a fuel pressure feeding passage 22c for feeding fuel pressurized in the working chamber 26 to fuel injection means (not shown) are provided. .

The fuel intake passage 21b and the fuel intake passage 22b communicate with each other via a communication passage 28 shown by a two-dot chain line in the figure. In addition, the fuel pressure delivery path 21c and the fuel pressure delivery path 22
c communicates with each other via a communication path 29 indicated by a two-dot chain line in the figure. Although the communication passages 28 and 29 are formed inside the first housing 21 and the second housing 22, they are shown by two-dot chain lines outside the housings 21 and 22 for convenience. Annular member 25 and recess 2
A suction valve 30a that allows only the flow of fuel from the fuel suction passage 21b to the inside of the working chamber 24 is provided between the suction valve 30a and the bottom of the suction chamber 30a.
A valve member 30 having a discharge valve 30b for permitting only the flow of fuel from the inside of the working chamber 24 to the fuel pressure supply passage 21c.
Are arranged.

Further, between the annular member 27 and the bottom of the concave portion 22a, a suction valve 31a for allowing only the flow of the fuel from the fuel suction passage 22b to the inside of the working chamber 26, and the inside of the working chamber 26 for the fuel. A valve member 31 having a discharge valve 31b that allows only the flow from the fuel supply passage 22c to the fuel pressure feed passage 22c is provided. The first valve means is constituted by the suction valve 30a and the suction valve 31a, and the second valve means is constituted by the discharge valve 30b and the discharge valve 31b. The third housing 23 has a cylindrical shape, and a pair of cylindrical cylinders 32a and 32b, which are vertically divided in the figure, are disposed in a substantially central portion inside the third housing 23, respectively. ing. A plunger 33 made of a magnetic material, for example, an iron material is slidably fitted inside the cylinders 32a and 32b. Both ends of plunger 33 and cylinders 32a, 32b
Of the working chambers 24 and 26.

Between the annular member 25 and one end of the plunger 33 and between the annular member 27 and the other end of the plunger 33,
Spring 34 biasing plunger 33 toward its center
a and 34b are respectively provided. Springs 34a, 3
4b are substantially equal to each other. An annular flange 33 protruding in the radial direction is provided at a substantially intermediate portion of the plunger 33.
a is integrally formed. Collar 33 of plunger 33
By a, the inside of the third housing 23 is divided into two upper and lower spaces. Plunger 3 in the upper space
3 is provided with a coil 35a for moving the coil 3 in the direction of arrow C in the figure. A coil 35b that moves the plunger 33 in the direction of arrow D in the figure is provided in the lower space. The above-mentioned springs 34a, 34b and coils 35a, 3
Plunger driving means is constituted by 5b.

The coils 35a and 35b are connected to a power supply via a power supply control means (not shown). Coil 35
a and 35b are fixed to the inner surface of the third housing 23 by cylindrical holding members 36a and 36b having flanges at both ends. Coil 35a, 35b
Are separated from each other by a predetermined distance. That is, the holding member 3
When the plunger 33 is moved in the cylinders 32a and 32b, the flange 33a of the plunger 33 does not come into contact with the holding members 36a and 36b earlier than the end face of the plunger 33 when the plunger 33 is moved within the cylinders 32a and 32b. Separated by a distance. On the side wall of the third housing 23, a fuel release passage 37 is provided as an outlet communicating with a space (reservoir M) in which the flange portion 33a of the plunger 33 moves, and the cylinders 32a and 32b, the plunger 33 and The fuel in the working chambers 24 and 26 leaking from between the tanks is directly returned to a fuel tank (not shown). For this reason, the operation of the plunger 33 is performed smoothly.

Next, the operation of the above-described electromagnetic reciprocating pump 20 will be described with reference to FIG. In the second embodiment, only the case where the power supply is a DC power supply is shown. First, when only the coil 35a is energized, the plunger 33 moves upward in the figure against the urging force of the spring 34a by the exciting action of the coil 35a, as shown in FIG. As the plunger 33 moves, the volume of the working chamber 24 decreases, and the fuel pressure in the working chamber 24 increases. This increase in fuel pressure causes the discharge valve 30b to open, and the pressurized fuel in the working chamber 24 is discharged through the discharge valve 30b to the fuel pressure feed path 21c, as shown by the arrow E in the drawing. On the other hand, in the working chamber 26,
The movement of the plunger 33 increases its volume, and the fuel pressure in the working chamber 26 decreases. This decrease in fuel pressure opens the suction valve 31a, and as shown by the arrow F in the figure,
Fuel is drawn into the working chamber 26 from the fuel suction passage 22b via the suction valve 31a.

Next, when the energization of the coil 35a is interrupted and the coil 35b is energized, as shown in FIG.
3 moves downward in the figure against the urging force of the spring 34b. When the plunger 33 moves, the working chamber 2
6, the fuel pressure in the working chamber 26 increases. This increase in fuel pressure causes the discharge valve 31b to open, and the pressurized fuel in the working chamber 26 is discharged to the fuel pressure feed passage 22c via the discharge valve 31b, as shown by the arrow H in the drawing. On the other hand, in the working chamber 24, the volume of the working chamber 24 increases due to the movement of the plunger 33, and the fuel pressure in the working chamber 24 decreases. This decrease in fuel pressure opens the suction valve 30a,
In the figure, as indicated by an arrow G, fuel is sucked into the working chamber 24 from the fuel suction passage 21b via the suction valve 30a. FIG. 5 shows a rectangular diagram illustrating the control of energization of the coils 35a and 35b. As shown in FIG. 5, the coils 35a, 35b
The energization to is performed alternately.

By repeatedly controlling the energization of the coils 35a and 35b, the fuel suction operation and the fuel discharge operation are repeatedly performed in the working chambers 24 and 26, and the pressurized fuel is supplied to the fuel injection means. Supplied to Therefore, in order to change the volume of the working chambers 24 and 26,
Since the plunger 33 having high rigidity is used, the fuel pressurized to a high pressure can be pumped. Further, since the reciprocating movement of the plunger 33 can be effectively used, the fuel can be efficiently pumped, and the pulsation of the fuel pressure (hereinafter simply referred to as fuel pressure pulsation) can be reduced as compared with the electromagnetic reciprocating pump 1 in the first embodiment. . FIG. 6 shows the characteristics of the fuel pressure pulsation by the electromagnetic reciprocating pump 1 in the first embodiment and the fuel pressure pulsation by the electromagnetic reciprocating pump 20 in the second embodiment. In the figure, a line T1 shows characteristics of fuel pressure pulsation by the electromagnetic reciprocating pump 20, and a line T2 shows characteristics of fuel pressure pulsation by the electromagnetic reciprocating pump 1.
In FIG. 6, when the characteristic line T1 and the characteristic line T2 are compared, the fuel pressure pulsation of the electromagnetic reciprocating pump 20 is reduced to approximately half that of the electromagnetic reciprocating pump 1, and the fuel pumping is stably performed. It can be carried out.

In this embodiment, the working chamber 24,
The fuel in the cylinder 26 passes through a gap between the inner surfaces of the cylinders 32a and 32b and the outer surface of the plunger 33,
Lubrication is performed. Next, a third embodiment is shown in FIG.
This embodiment will be described. The electromagnetic reciprocating pump according to the third embodiment differs from the electromagnetic reciprocating pump according to the second embodiment only in the configuration of the plunger. Therefore, here, the configuration of the plunger and its operation will be described. I do. In FIG. 7, the illustration of the first and second housings 21 and 22 is omitted, and the same members as those shown in FIG. 3 are denoted by the same reference numerals as those used in FIG. Are omitted, and the differences will be described.

A plunger 40 is slidably fitted inside the cylinders 32a and 32b. Plunger 4
Reference numeral 0 denotes a first main body 41, a second main body 42, and an annular flange 43 protruding in the radial direction of the plunger 40. The flange 43 has an inner peripheral edge sandwiched between the two main bodies at a substantially intermediate portion of the plunger 40, and is formed integrally with the first main body 41 and the second main body 42. The collar 43 is formed of a permanent magnet, and its upper surface is an N pole and its lower surface is an S pole. Next, the operation of the above-described plunger will be described with reference to FIG.

As shown in FIG. 8A, the coils 35a,
The coils 35a and 35b are energized such that N poles are generated on each side of the flange 35b facing the flange 43. The energization in this manner generates a repulsive force between the coil 35a and the collar 43. Further, an attractive force is generated between the coil 35b and the flange 43.
By these forces, the collar 43, that is, the plunger 40, moves in the direction of the arrow J in the drawing. By the movement of the plunger 40, the pressurized fuel in the working chamber 26 is discharged to the fuel pressure feed passage 22c via the discharge valve 31b, similarly to the operation of the electromagnetic reciprocating pump 20 in the second embodiment. Further, the fuel is supplied from the fuel suction passage 21b to the suction valve 30a.
Is sucked into the working chamber 24 through

Next, as shown in FIG.
The coils 35a and 35b are energized so that S poles are generated on each side of the flanges 5a and 35b facing the flange 43. By energizing in this manner, the coil 3
An attraction force is generated between 5a and the collar portion 43, and a repulsive force is generated between the coil 35b and the collar portion 43. By these forces, the collar 43, ie, the plunger 40, moves in the direction of arrow K in the figure. By the movement of the plunger, fuel is sucked from the fuel suction passage 22b into the working chamber 26 via the suction valve 31a, similarly to the operation of the electromagnetic reciprocating pump 20 in the second embodiment. The pressurized fuel in the working chamber 24 is discharged to the fuel pressure feed passage 21c via the discharge valve 30b. Note that the coils 35a, 3
FIG. 9 shows a rectangular diagram illustrating the control of energization of 5b. As shown in the figure, energization of the coils 35a and 35b is performed simultaneously.

By repeatedly controlling the energization of the coils 35a and 35b, the fuel suction operation and the fuel discharge operation are repeatedly performed in the working chambers 24 and 26, and the pressurized fuel is supplied to the fuel injection means. Supplied to In the above-described first and second embodiments, only the attraction force of the coil is used to move the plunger. However, in the present embodiment, in addition to the attraction force of the coil, Repulsion is also used by using a plunger as a permanent magnet. Therefore, the moving force of the plunger 40, that is, the pumping force can be increased, and the fuel can be pressurized to a higher pressure than the electromagnetic reciprocating pump in the above-described first and second embodiments. Further, when performing the same fuel pressure feeding as the electromagnetic reciprocating pump in the first and second embodiments described above, the present embodiment utilizes the repulsive force and the attractive force of the permanent magnet. The amount of current generated can be reduced, and the size of the pump can be reduced.

[0028]

As described above, according to the first aspect of the present invention, high-pressure fluid can be pumped without increasing the sliding resistance of the plunger.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electromagnetic reciprocating pump according to a first embodiment.

FIGS. 2A and 2B are explanatory diagrams of the operation of the electromagnetic reciprocating pump according to the first embodiment. FIG. 2A shows the state of the plunger when energizing the coil, and FIG. 2B shows the state when energizing the coil is interrupted. The state of the plunger is shown.

FIG. 3 is a longitudinal sectional view of an electromagnetic reciprocating pump according to a second embodiment.

FIG. 4 is an explanatory view of the operation of the electromagnetic reciprocating pump according to the second embodiment, in which (a) shows the state of the plunger when energizing one coil and interrupting energizing the other coil; b) shows the state of the plunger when power is supplied to the other coil and power supply to one coil is interrupted, respectively.

FIG. 5 is a rectangular diagram illustrating control of energizing a coil of an electromagnetic reciprocating pump according to a second embodiment.

FIG. 6 shows an electromagnetic reciprocating pump according to the first embodiment;
FIG. 9 is a waveform diagram showing a change in fuel pressure pulsation caused by the electromagnetic reciprocating pump according to the second embodiment.

FIG. 7 is a partially enlarged longitudinal sectional view of an electromagnetic reciprocating pump according to a third embodiment.

8A and 8B are explanatory diagrams of the operation of the plunger in the third embodiment, wherein FIG. 8A shows a state when the plunger moves in one direction, and FIG. 8B shows a state when the plunger moves in the other direction. Show.

FIG. 9 is a rectangular diagram illustrating control of energizing a coil of an electromagnetic reciprocating pump according to a third embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electromagnetic reciprocating pump 2 first housing 3 second housing 4 third housing 6 valve member 6a suction valve (first valve means) 6b discharge valve (second valve means) 7 working chamber 8 fuel suction Road 9 Fuel pressure feeding path 10 Coil (plunger driving means) 11 Cylinder 12 Plunger 15, 37 Fuel release path M Storage chamber

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akihito Miyamoto 5-33-8 Shiba, Minato-ku, Tokyo F-term in Mitsubishi Motors Corporation (Reference) 3H069 AA06 BB02 CC04 DD26 DD31 DD48 EE11 EE47 3H071 AA07 BB01 CC22 CC27 CC47 DD12 DD13 DD89 3H075 AA03 BB03 CC10 CC15 CC17 DA01 DA04 DA09 DA17 DB08

Claims (1)

[Claims] 1. A housing having a cylinder communicating with a suction port for sucking a fluid and a discharge port for discharging the fluid, a plunger slidably fitted in the cylinder, and an exterior of the cylinder for the fluid. First valve means for permitting only the flow from the inside to the inside, second valve means for permitting only the flow of the fluid from the inside to the outside of the cylinder, provided in the housing, and provided by the exciting action of the coil A plunger driving means for reciprocating the plunger, sucking the fluid from the suction port into the cylinder, and discharging the fluid from the discharge port to the outside of the cylinder; It has a storage chamber for storing fuel leaked from the sliding surface, and an outlet for allowing fuel in the storage chamber to flow out of the housing. Electromagnetic reciprocating pump.