JP2001041148A - Electromagnetic pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double-acting electromagnetic pump which facilitates clearance control, eliminates the possibility of lowering of performance due to abrasion and can be increased in pressure by an increase in size of an armature. SOLUTION: Small-diameter cylinders 3A, 3B and large-diameter armature sliding spaces 4A, 4B are formed in housings 1A, 1B of a two-split structure. Pistons 5A, 5B are respectively inserted in the cylinders 3A, 3B to form pump chambers 6A, 6B. An armature 7 provided separately from the pistons 5A, 5B and driven by solenoids 12A, 12B of the housing 1 are stored in the armatures sliding spaces 4A, 4B, and made abut on the right and left pistons 5A, 5B. Thus, the pump chambers 6A, 6B are alternately caused to perform pump action, whereby air is sucked from intake passages 13A, 13B and delivered from delivery passages 14A, 14B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-acting electromagnetic system in which a reciprocating member reciprocated by an electromagnetic force changes the volume of two pump chambers provided on the left and right sides thereof to alternately perform a pumping operation. Related to pumps.

[0002]

2. Description of the Related Art As a conventional electromagnetic pump, a reciprocating member reciprocated by an electromagnetic force, particularly a piston which is a part of the reciprocating member which performs a pumping operation, is used.
There is a type in which the volume of a pump chamber in a cylinder formed in a housing is changed to perform a pumping operation (Japanese Patent Application Laid-Open No.
-68157).

Further, as a double-acting electromagnetic pump, each of the left and right housings is formed by a reciprocating member reciprocated by an electromagnetic force, in particular, a piston which is a part of the reciprocating member that performs a pump action. There is one in which the volume of a pump chamber in a cylinder is changed so that two pump chambers alternately perform a pumping action, and the piston itself is formed of a magnetic material so that the piston also serves as an armature.

[0004]

However, in the above-mentioned double-acting electromagnetic pump, the housing is divided into two parts at the center, and one piston slides in the cylinder of each housing. Therefore, there is a problem in that a radial error of the piston sliding portion easily occurs due to a positional error of the two divided housings, and it is difficult to manage the clearance.

Further, since the piston itself also serves as an armature, it is difficult to obtain a high hardness of a piston made of a magnetic material. There was a problem that there was concern about a decrease.

In addition, there is a problem that it is difficult to increase the pressure since the armature cannot be made larger and a large electromagnetic force cannot be configured. The present invention has been made in view of the above-described conventional problems, and a double-acting electromagnetic pump that facilitates clearance management, has no risk of performance deterioration due to wear, and enables high pressure to be achieved by enlarging an armature. The purpose is to provide.

[0007]

According to the present invention, the volume of the pump chamber in each of the cylinders formed in the left and right housings is changed by the reciprocating member reciprocated by the electromagnetic force. Further, in the electromagnetic pump in which the two pump chambers alternately perform the pumping action, the left and right pistons, which are parts of the reciprocating member that perform the pumping action, are configured separately.

In the invention according to claim 2, the armature, which is a portion of the reciprocating member that receives electromagnetic force from the solenoid on the housing side, is formed separately from the left and right pistons and is in contact with each other. I do.

The invention according to claim 3 is characterized in that a liner having a higher hardness than the main body of the armature is attached to a contact portion of the armature with the piston. The invention according to claim 4 is characterized in that a contact portion of the piston with the armature is a spherical convex portion.

The invention according to claim 5 is characterized in that a spring for urging the armature to a neutral position is provided, and a spring for contacting each of the pistons with the armature is provided.

The invention according to claim 6 is characterized in that the clearance between the armature and its sliding space is made larger than the clearance between the piston and the cylinder.

The invention according to claim 7 is characterized in that the outer diameter of the armature is larger than the outer diameter of the piston. The invention according to claim 8 is characterized in that the armature is provided with a communication passage for communicating the left and right chambers of the sliding space. Here, the communication passage may be formed as a communication groove extending in the movement direction on the outer peripheral surface of the armature (claim 9) or may be formed in the armature as a communication hole penetrating in the movement direction (claim 9). Claim 10).

According to an eleventh aspect of the present invention, a drain passage is provided from each of the left and right chambers of the sliding space for the armature, and each drain passage is connected to a suction passage to a pump chamber located on the opposite side. Features.

[0014]

According to the first aspect of the invention, since the left and right pistons are formed separately, even if there is a positional error in the divided housing, each piston can be smoothly moved in each cylinder. Sliding movement can be performed, and clearance management becomes easy, for example, it is not necessary to perform precise spigot alignment for housing alignment.

According to the second aspect of the present invention, the portion for performing the pumping action (piston) and the portion for receiving the electromagnetic force (armature) have a separate structure, so that a material having high hardness is used for the piston portion. Therefore, there is no need to worry about performance degradation due to wear and the like even when using a non-lubricating working fluid such as gasoline, and the armature size can be set arbitrarily with respect to the piston diameter. It is also possible to gain power.

According to the third aspect of the present invention, the abrasion of the contact portion can be prevented by mounting the high-hardness liner on the contact portion of the armature with the piston. According to the fourth aspect of the present invention, since the contact portion of the piston with the armature is formed as a spherical convex portion, it is possible to prevent the occurrence of a prying force.

According to the fifth aspect of the present invention, the operation can be stabilized by providing the spring for urging the armature to the neutral position and the spring for contacting each piston with the armature.

According to the sixth aspect of the present invention, the clearance between the armature and its sliding space is made larger than the clearance between the piston and the cylinder, so that the wear of the armature can be prevented.

According to the invention according to claim 7, the outer diameter of the armature is made larger than the outer diameter of the piston.
The armature can be increased in size to allow a large electromagnetic force to work, and high pressure can be achieved.

According to the eighth aspect of the present invention, since the armature is provided with the communication path for communicating the left and right chambers of the sliding space, the stirring resistance during movement of the armature can be reduced. Here, by forming the communication passage as a communication groove in the outer peripheral surface of the armature, the centering action of the armature can be obtained (claim 9). Also, by forming the communication hole inside the armature, the electromagnetic force is not hindered (claim 10).

According to the eleventh aspect of the present invention, since the drain passages from the left and right chambers of the sliding space of the armature are connected to the suction passage to the pump chamber on the opposite side, the pressure is increased by the movement of the armature. The working fluid can be supplied from the chamber to the pump chamber in the suction stroke, suppressing the pressure increase due to the movement of the armature, not only reducing the resistance, but also improving the suction performance of the pump chamber. Can be improved.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of an electromagnetic pump showing one embodiment of the present invention.

The housings 1A and 1B are divided into two parts on the left and right sides, and have a structure in which the housing 1A and 1B are joined via a sealing material 2 at the center joint surface. Each housing 1A, 1B has a small-diameter cylinder (piston sliding space) 3A, 3B on the same axis.
And a large-diameter armature sliding space 4 on the joint surface side thereof
A and 4B are formed.

The ends of the pistons 5A and 5B are slidably inserted into the cylinders 3A and 3B, respectively, thereby being defined by the end faces of the pistons 5A and 5B in the cylinders 3A and 3B. Pump chambers 6A and 6B are formed.

In the armature sliding spaces 4A and 4B,
An armature 7 made of a magnetic material having a larger diameter than the pistons 5A and 5B is housed so as to straddle the joint surface. Here, compared to the radial clearance between the cylinders 3A, 3B and the pistons 5A, 5B, the armature sliding space 4
The radial clearance between A, 4B and the armature 7 is increased.

The armature sliding spaces 4A and 4B (left and right chambers of the armature 7) accommodate springs (return springs) 8A and 8B, respectively, and act on the armature 7 to urge the armature 7 to the neutral position. is there.

Springs (return springs) 9A and 9B are accommodated in the pump chambers 6A and 6B, respectively, and act on the pistons 5A and 5B, respectively, so that the pistons 5A and 5B abut on the armature 7.

Here, as shown in FIGS. 2 and 3, the contact portions between the pistons 5A and 5B and the armature 7 are
A disk-shaped liner (sheet material) 10A, 10B having higher hardness than the armature 7 (magnetic material) is provided on the armature 7 side.
And the pistons 5A and 5B are brought into contact with these liners 10A and 10B. In addition, pistons 5A, 5
As shown in FIG. 2, the contact portion on the B side is a spherical convex portion 11.

In order to drive the armature 7, a pair of solenoids (electromagnetic coils) 12A and 12B are provided on the housings 1A and 1B so as to be shifted left and right in the axial direction of the pistons 5A and 5B with respect to the armature 7 at the neutral position. It is arranged.

In order to cause the pump chambers 6A and 6B to perform a pumping operation, the pump chambers 6A and 6B are provided with suction passages 13A and 13B and discharge passages 14A and 14B.
B is provided.

Suction passage 13 to each pump chamber 6A, 6B
A and 13B are for sucking a low-pressure working fluid (low-pressure fuel) from a working fluid source (fuel source) (not shown), and are connected to positions closed by the pistons 5A and 5B when the pistons 5A and 5B are in the neutral position. Then, when the pistons 5A, 5B move in the direction of increasing the volume of the pump chambers 6A, 6B, they open to the pump chambers 6A, 6B.

The discharge passage 14 from each of the pump chambers 6A, 6B
A and 14B supply a high-pressure working fluid (high-pressure fuel) to a supply unit (not shown), and are derived from positions that always open to the pump chambers 6A and 6B regardless of the positions of the pistons 5A and 5B. . Then, each discharge passage 14A, 1
Check valve 15 that allows only the flow in the discharge direction is provided for 4B.
A and 15B are provided.

The armature 7 is provided with a communication passage 16 for connecting the left and right chambers of the sliding spaces 4A and 4B. As the communication passage 16, as shown in FIG. 4, a plurality of communication grooves (16) extending in a direction parallel to the axis of the armature 7 are provided on the outer peripheral surface of the armature 7 at equal intervals in the circumferential direction, or as shown in FIG. In the armature 7, a plurality of communication holes (16) penetrating in a direction parallel to the axis of the armature 7 are provided at equal intervals in the circumferential direction.

Also, each armature sliding space 4A, 4B
(A left and right chamber of the armature 7) A drain passage 17 for draining the working fluid (fuel) leaked to the chamber 7
A and 17B are derived and formed, and the respective drain passages 17A and 17B are formed.
B is a suction passage 13B to the pump chambers 6B and 6A on the opposite side,
13A.

Next, the operation will be described. The armature 7 slides on the inner surfaces of the armature sliding spaces 4A, 4B with a clearance fit (with a relatively large clearance) that allows an assembly error between the housings 1A, 1B, and is driven by the solenoids 12A, 12B. Is done.

Therefore, the armature 7 has its sliding space 4
Piston 5 while tilting by the clearance between A and 4B
A and 5B are driven, but are separate from the pistons 5A and 5B, and the end surfaces of the abutting portions of the pistons 5A and 5B have a spherical shape (11). The pistons 5A and 5B can be driven without giving a prying force via the pistons 10A and 10B.

Further, even if the weight of the armature 7 increases, there is no fear of giving a prying force to the pistons 5A and 5B.
The outer diameter of the armature 7 is made larger than the outer diameter of the separate pistons 5A and 5B, so that a larger electromagnetic force can be obtained.

On the other hand, the pistons 5A and 5B do not receive a twisting force, and since the mating surfaces of the housings 1A and 1B are not sliding surfaces, the clearance between the pistons 5A and 5B and the cylinders 3A and 3B can be minimized.

Here, for example, the right solenoid 1
When power is supplied to 2B, the armature 7 is driven to be sucked rightward as shown in the figure, the piston 5B moves in the same direction, and the piston 5A also follows the spring 9A.

As a result, in the right pump chamber 6B, the volume thereof is reduced and the suction passage 13B is closed, so that the internal fuel is compressed and the check valve 15B of the discharge passage 14B is opened due to an increase in the internal pressure. Thus, high-pressure fuel is discharged.

Conversely, in the left pump chamber 6A, the volume is increased and the suction passage 13A is opened, so that the fuel is sucked. Next, the right solenoid 12B
To the solenoid 1 on the left.
When power is supplied to 2A, the armature 7 is sucked and driven leftward, contrary to the illustration, the piston 5A moves in the same direction, and the piston 5B also follows the spring 9B.

As a result, in the left pump chamber 6A, the volume is reduced and the suction passage 13A is closed, so that the internal fuel is compressed and the internal pressure rises, so that the check valve 15A of the discharge passage 14A is opened. High pressure fuel is discharged.

Conversely, in the left pump chamber 6B, the volume is increased, and the fuel is sucked in by opening the suction passage 13B. Such an operation is repeated, and the suction and discharge operations are alternately performed by the two left and right pump chambers 6A and 6B.

Here, the armature 7 is mounted on the sliding space 4.
A communication groove 16 as shown in FIG. 4 is provided on the outer peripheral surface of the armature 7 in order to minimize the stirring resistance of the fuel in the armature sliding spaces 4A and 4B when sliding movements in the armatures 4 and 4B. And the sliding space 4 in the armature 7
It is possible to effectively reduce the stirring resistance while obtaining the centering action on the inner surfaces of A and 4B.

Also, instead of the communication groove, an armature 7
When the communication hole 16 as shown in FIG. 5 is provided inside the fuel cell, it is possible to reduce the fuel stirring resistance without hindering the generation of the electromagnetic force.

The armature sliding space 4A, 4B (the left and right chambers of the armature 7) is slightly pressurized by the left and right movement of the armature 7, but the drain passages 17A, 17B from the left and right chambers of the armature 7 respectively. To suction chambers 13B, 13A to pump chambers 6B, 6A on the opposite side.
By connecting the armature A, the leaked fuel slightly pressurized can be supplied from the chamber (for example, 4B) on the side where the pressure is increased by the movement of the armature 7 to the pump chamber (for example, 6A) in the suction stroke. Not only reduces the resistance, but also improves the suction performance of the pump chamber (for example, 6 A). Therefore, it is possible to improve the suction performance particularly at the time of high rotation.

[Brief description of the drawings]

FIG. 1 is a sectional view of an electromagnetic pump showing one embodiment of the present invention.

FIG. 2 is a detailed view of a contact portion between an armature and a piston.

FIG. 3 is an end view of an armature liner mounting portion.

FIG. 4 is a sectional view showing an example (1) of an armature with a communication passage;

FIG. 5 is a sectional view showing an example (2) of an armature with a communication passage;

[Explanation of symbols]

 1A, 1B Housing 2 Seal material 3A, 3B Cylinder (piston sliding space) 4A, 4B Armature sliding space 5A, 5B Piston 6A, 6B Pump chamber 7 Armature 8A, 8B Spring 9A, 9B Spring 10A, 10B Liner 11 Spherical 12A, 12B Solenoid 13A, 13B Suction passage 14A, 14B Discharge passage 15A, 15B Check valve 16 Communication passage (communication groove or communication hole) 17A, 17B Drain passage

Continuing from the front page (72) Inventor Kenmei Kubo 2 Takara-cho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Nissan Motor Co., Ltd. (72) Inventor Shigeru Kamegaya 2 Takara-cho, Kanagawa-ku, Yokohama City, Kanagawa Prefecture F-term (reference) 3H069 AA06 BB03 CC05 DD45 DD48 EE05 3H075 AA03 BB16 CC10 CC24 CC37 DA04 DA09 DB08

Claims (11)

[Claims] An electromagnetic force that alternately pumps two pump chambers by changing the volume of pump chambers in respective cylinders formed in left and right housings by a reciprocating member reciprocated by electromagnetic force. In the pump, the left and right pistons, which are parts of the reciprocating member that perform a pumping operation, are configured separately. 2. The reciprocating member according to claim 1, wherein the armature, which is a portion for receiving an electromagnetic force from a solenoid on the housing side, is formed separately from the left and right pistons and is in contact with each other. Electromagnetic pump. 3. The electromagnetic pump according to claim 2, wherein a liner having a higher hardness than the main body of the armature is attached to a contact portion of the armature with the piston. 4. The electromagnetic pump according to claim 2, wherein a contact portion of said piston with said armature is a spherical convex portion. 5. The apparatus according to claim 2, further comprising a spring for urging said armature to a neutral position, and a spring for bringing said pistons into contact with said armature.
The electromagnetic pump according to claim 4. 6. A clearance between the armature and a sliding space thereof is made larger than a clearance between the piston and the cylinder.
The electromagnetic pump according to any one of the above. 7. The electromagnetic pump according to claim 2, wherein an outer diameter of the armature is larger than an outer diameter of the piston. 8. The electromagnetic pump according to claim 2, wherein a communication passage is formed in the armature for communicating the left and right chambers of the sliding space. 9. The electromagnetic pump according to claim 8, wherein said communication passage is formed as a communication groove extending in the movement direction on an outer peripheral surface of said armature. 10. An electromagnetic pump according to claim 8, wherein said communication passage is formed as a communication hole penetrating in the moving direction inside said armature. 11. The armature according to claim 2, wherein drain passages are provided from left and right chambers of the sliding space of the armature, and each drain passage is connected to a suction passage to a pump chamber located on the opposite side. The electromagnetic pump according to claim 10.