JP2573564Y2 - Electromagnetic reciprocating 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 reciprocating pump, and more particularly, to an electromagnetic reciprocating pump capable of reducing the weight of an armature provided on a piston for reciprocating the piston by electromagnetic force. It relates to a type pump.

[0002]

2. Description of the Prior Art A piston having a piston head slidably disposed in a cylinder is biased in one direction by a spring so that its magnetic pole is located outside an armature provided on the piston. 2. Description of the Related Art A pump of a type in which a fluid is repeatedly sucked / discharged by periodically sucking and discharging a fluid in a direction opposite to the above direction by using an electromagnet arranged in a casing (hereinafter referred to as an electromagnetic reciprocating pump) is known. is there. The electromagnet includes a pair of magnetic poles for attracting an armature.

In this known electromagnetic reciprocating pump, heat is dissipated by frictional heat between a piston and a main shaft or a cylinder slidably supporting the piston, Joule heat generated in an electromagnetic circuit, iron loss, and the like. Is not sufficiently performed, there is a problem that the main shaft, cylinder, piston, etc. thermally expand, and the reciprocation of the piston is not smooth.

[0004] The sliding bearings provided on the piston, the main shaft or the cylinder also have a problem that the service life is adversely affected by the temperature rise and the service life is shortened.

In order to solve such a problem at a stretch, the applicant of the present application has disclosed in Japanese Patent Application No. Hei 3-11456 a type in which a piston is slidably mounted on a main shaft fixed to a casing of a pump. In the pump, the main shaft has a hollow structure, and when the piston reciprocates, the suction / discharge fluid passes through the hollow main shaft and is guided into the pump casing to cool the main shaft and the casing. An electromagnetic reciprocating pump has already been proposed. In this pump, the cooling action during the operation can prevent thermal expansion of the main shaft, cylinder, piston, etc., and shortening of the life of the sliding bearing.

[0006]

As described above, it is necessary to attach an armature to the piston, but this armature is usually formed by laminating a plurality of annular plates (donut-like plates) made of a magnetic material. Is formed. The piston is cast after fitting the armature into a piston mold.

By the way, in the pump of the type described in the above publication, the piston is inserted through the main shaft having a hollow structure, or the load per unit area of a bearing member disposed between the piston and the main shaft is used. Due to limitations, relatively large through holes are required. For this reason, the armature attached to the piston also needs a hole with a larger diameter than the through hole, but if the diameter of this hole is too large,
Inevitably, the outer diameter of the armature also becomes large, and the armature and, consequently, the electromagnetic reciprocating pump increase in weight.

Further, when the hole diameter of the armature is reduced, the thickness of the armature mounting portion after the armature is cast into the piston becomes small, and the strength of the piston becomes insufficient.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an electromagnetic reciprocating motion capable of increasing the hole diameter of an armature without increasing the outer diameter of the armature. It is to provide a type pump.

[0010]

In order to solve the above-mentioned problems, the present invention provides an electromagnet for attracting an armature having an even number of magnetic poles of four or more, that is, a multipole structure, and a magnetic pole between adjacent magnetic poles. The present invention is characterized in that the coil is wound so that the magnetic flux forms a closed loop through the armature.

In addition, a through hole is formed in the piston, and a hollow main shaft is inserted into the through hole so that the piston reciprocates on the main shaft, and a fluid is sucked into the pressure chamber by the reciprocating motion, or When discharging the fluid from the pressure chamber, the fluid passes through the hollow main shaft and the casing,
It is also characterized in that an electromagnet and a piston in the casing, or a bearing provided between the main shaft and the piston are cooled.

[0012]

When the number of magnetic fluxes to the armature (the total number of magnetic fluxes entering and leaving the armature) is the same, the force acting on the armature is the same. Therefore, the number of magnetic poles facing the armature is reduced by 2
If the force acting on the armature can be the same if the number of magnetic poles is increased to an even number of four or more, the cross-sectional area of the magnetic pole may be reduced by the increased number of magnetic poles. Further, since the coil of the electromagnet is wound between the adjacent magnetic poles so that the magnetic flux forms a closed loop via the armature, the sectional area of the armature may be small. That is, the inner diameter of the armature can be increased.

Further, in a configuration in which a through hole is formed in the piston, a hollow main shaft is inserted into the through hole, the piston is supported by the main shaft, and the pump is cooled when a fluid is sucked or discharged. As the inner diameter increases, the thickness from the inner wall of the armature to the inner wall of the piston, that is, the thickness of the armature mounting portion increases.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. FIG. 2 is a cross-sectional view of one embodiment of the present invention, and FIG. 1 is a side view of the field core 100 and the armature 8.
In FIG. 1, a piston 6, a slide bearing 7 and a main shaft 5 are shown in cross section, and a coil 2 wound around a magnetic pole 1 is shown.
Is shown in simplified form. Further, in FIG. 1, the flow of the magnetic flux is indicated by a broken line.

In each figure, the field core 100
Is provided with four magnetic poles 1 protruding inward from the annular frame, and a coil 2 is wound around each magnetic pole 1.
The winding of the coil 2 is, as shown by a broken line in FIG.
The magnetic flux is formed between the adjacent magnetic poles 1 through the armature 8 so as to form a closed loop. The field core 100 and the coil 2 constitute an electromagnet.

The field core 100 is sandwiched and fixed by a front casing 3 having a cylinder 3A at a front end thereof and a rear casing 4, and the front casing 3 and the rear casing 4 form a closed casing. The field core 100 is arranged so that the four magnetic poles 1 are located outside a piston 6 to be described later in a substantially central portion of the closed casing.

A hollow main shaft 5 is fixed to the front casing 3 so that the center axis thereof coincides with the center axis of a cylinder 3A formed at the front. The front end opening 5F of the hollow main shaft 5 is disposed at a position that is substantially the shortest distance from the air introduction opening 52 formed on the front surface of the cover 51, so that outside air can be introduced into the fluid passage 5A inside the hollow main shaft 5. The rear end opening 5B of the fluid passage 5A is open toward the internal space of the rear casing 4, and air flows through the fluid passage 5A.
It flows from A to the rear in A.

Fins (not shown) for improving the heat radiation of the hollow main shaft 5 are provided on the inner surface of the fluid passage 5A.
Since it is formed in the axial direction of the main shaft toward the centripetal direction,
The introduced air flows between the fins toward the rear end opening 5B. The fin may be formed integrally with the fluid passage 5A of the main shaft 5, or may be formed by fitting a separately formed member to the inner surface of the fluid passage 5A in a state of thermal close contact. This fin can be omitted.

A piston 6 having a piston head 6A is slidably inserted through the outer peripheral surface of the hollow main shaft 5.
A slide bearing 7 is provided on the outer peripheral surface of the main shaft 5 or the inner peripheral surface of the piston 6, whereby the piston 6 reciprocates more smoothly. A sliding bearing 6D is also provided on the inner peripheral surface of the cylinder 3A or the outer peripheral surface of the piston head 6A. A pressure chamber 12 is defined by the cylinder 3A and the piston head 6A.

The piston head 6A is provided with a suction port 6B, and the suction port 6B is closed by a suction valve 6C.
FIG. 2 shows the moment when the piston 6 starts the forward movement (movement in the direction in which the compression coil spring 9 described later is compressed), so that the suction valve 6C is open. A discharge port 13 is provided on a side wall of the cylinder 3A.
4 is closed. When the piston 6 moves forward, the discharge valve 14 is closed, but FIG. 2 shows an open state for convenience of explanation. The armature 8 attached to a substantially central portion of the piston 6 can be integrally assembled when the piston 6 is formed by, for example, aluminum die casting.

The compression coil spring 9 includes the piston 6 and
The rear casing 4 is disposed on the same central axis between the rear casing 4 and the rear end face. The end of the compression coil spring 9 on the piston 6 side is fixed to the piston 6,
An end on the rear casing 4 side is provided by a thrust bearing (not shown) fixed to the rear end inner wall of the rear casing 4 or a rotatable ring similar thereto.
The piston 6 is rotatably supported around the central axis of the piston 6. When the piston 6 rotates within the cylinder 3A, the compression spring 9 can also rotate in the same direction.

In the above embodiment of the present invention, when the coil 2 is energized, the armature 8 is attracted in the direction of the magnetic pole 1 against the elastic force of the compression spring 9 and the volume of the pressure chamber 12 increases. Then, the suction valve 6C is opened, and the air in the closed casing is sucked into the pressure chamber 12 from the suction port 6B. When the energization of the coil 2 is stopped, the piston 6 returns to the initial position by the resilient force of the compression coil spring 9, the suction port 6B is closed by the valve 6C, and the volume of the pressure chamber is reduced. The air in the chamber 12 is pressurized.

Therefore, as shown in FIG. 3, if the four coils 2 and the diode 81 are connected in series to an AC power supply 82 and half-wave AC is supplied to each coil 2 in the same cycle, Is excited, the piston 6 moves forward, and when the coil 2 is deenergized, the compression coil spring 9 acts to move the piston 6 backward (moving in the direction opposite to the forward movement), and this action is synchronized with the AC frequency. Is repeated.

As a result, when the piston 6 moves backward, that is, when the piston 6 moves forward, the inside of the closed casing is depressurized, so that the front casing 3 and the rear casing 3 are connected via the fluid inlet 52 and the fluid passage 5A of the hollow main shaft 5. Air is introduced into 4. When the piston 6 moves forward, that is, when the piston 6 moves backward, the suction valve 6C is opened as shown in FIG. 2, so that the air introduced into the front and rear casings flows into the suction port 6B and the suction valve 6C.
C is introduced into the pressure chamber 12 via C. The air introduced into the pressure chamber 12 is pressurized in the same chamber at the time of the next return movement of the piston 6, and when the pressure inside the pressure chamber 12 reaches a set pressure, the discharge valve 14 is opened, and the discharge port 13 and the discharge valve The liquid is discharged into the closed tank 51B through the outlet 14 and discharged toward the consumption source through the fluid discharge port 53.

In this way, while the suction of air and the discharge of pressurized air are performed repeatedly, the air passes through the fluid passage 5A in the hollow main shaft 5 supporting the reciprocating piston 6, so that the hollow The main shaft 5 is cooled from the inside. After passing through the hollow main shaft 5, the air enters the rear casing 4 and the front casing 3, further cools the coil 2 and the magnetic pole 1, and also cools the piston 6 and the armature 8,
In addition, the sliding bearing 7 supporting the piston 6 is prevented from rising in temperature due to the oscillating friction of the piston.

The electromagnet of the electromagnetic reciprocating pump has four magnetic poles 1 as shown in FIG. 1, and a coil is formed between adjacent magnetic poles 1 through an armature 8 so that a magnetic flux forms a closed loop. 2 is wound, so that the sectional area of the armature 8 (the sectional area taken along a plane perpendicular to the magnetic flux passage direction) is compared with a conventional electromagnet having only two magnetic poles as shown in FIG. Area) may be １ ／.

That is, assuming that the total number of magnetic fluxes for attracting the armature 8 is Φ, if the total number of magnetic fluxes Φ is the same, the attraction force is the same. Accordingly, if four magnetic poles are provided for two conventional magnetic poles, and if the same attractive force is sufficient, the total number of magnetic fluxes Φ passing through each magnetic pole is １ ／.
Only needs to be done. Therefore, the cross-sectional area of the armature 8 can be reduced to half that of the conventional one. Of course, the cross-sectional area of the magnetic pole 1 is also halved compared to the conventional one.

As a result, if the outer diameter (diameter) of the armature 8 is the same, the inner diameter can be increased. Accordingly, the armature 8 is reduced in weight, and the thickness from the inner wall of the armature 8 to the inner wall of the piston 6 can be set relatively large, and the strength of the piston 6 can be sufficiently secured. Furthermore, the diameter of the main shaft 5 can be increased, and wear of the slide bearing 7 is reduced.

In addition, even if the number of magnetic poles increases, if the attraction force of the armature can be the same, the number of ampere turns (AT) of the air gap is the same, and the number of turns of the coil may be the same as the conventional one. In FIG. 7, a piston, a main shaft, and the like to be arranged inside the armature 8 are omitted.

As shown in FIG. 1, the field core 100 includes a rectangular frame and four magnetic poles 1 formed to protrude inward from the frame. When the coil 2 is wound around the magnetic pole 1, the coil 2 may be wound directly around the magnetic pole 1, but it is technically difficult and the space utilization factor (space factor) is poor. Therefore, a coil may be wound around a bobbin that can be inserted into the magnetic pole 1 in advance, and the bobbin after the coil winding may be inserted into the magnetic pole 1.

In this case, at least one of the magnetic poles
If one is configured to be detachable from the frame of the field core, the bobbin can be easily inserted into the magnetic pole. FIG.
FIG. 4 is a side view of the field core when two of the four magnetic poles are configured to be detachable from the frame of the field core. In the same drawing, the armature 8 and the like are also shown as in FIG.

In FIG. 4, the field core 200 is
It comprises a frame 201 and a pair of magnetic poles 203. The pair of magnetic poles 203 and the pair of magnetic poles 202 provided on the frame 201 are provided so that the distance from the armature 8 is equal on the piston side. The frame 201 includes a pair of magnetic poles 202 facing each other and a pair of recesses 204 formed between the magnetic poles 202. Magnetic pole 203
Has a convex portion 203A substantially similar to the concave portion 204, and the convex portion 203A can be fitted into the concave portion 204. According to such a configuration, the bobbin 85 around which the coil 2 is wound can be inserted into the magnetic pole 203 and the magnetic pole 202 with the magnetic pole 203 removed from the frame 201. After the bobbin 85 is inserted, the magnetic pole 203 is
If it attaches to 01, an electromagnet will be completed.

When a coil is wound around four magnetic poles as shown in FIG. 4, if the coil can be wound in a conical shape around each magnetic pole, the number of turns can be increased. The required conductor cross-sectional area can be increased. FIG. 5 shows an example in which a coil is wound in a cone shape.
Has an area around which two coils (coil 2A and coil 2B) having different outer diameters are wound. Bobbin 8
7 are three coils (coils 2C to 2C) having different outer diameters.
E) is provided. By using such a bobbin that winds the coil in a multi-stage shape, it is possible to wind the coil substantially in a cone shape. In FIG. 5, bobbins around which coils are wound are mounted on only two of the four magnetic poles, but bobbins are mounted on the four magnetic poles, respectively, as in FIG. The same type of bobbin may be used for all magnetic poles, or different bobbins may be used.

In the above description, a coil is wound around all four magnetic poles. However, a coil may be wound every other magnetic pole, for example. In this case, the number of turns of the coil per pole is doubled.

The number of magnetic poles is not limited to four, but may be an even number of four or more. Also in this case, if the magnetic flux forms a closed loop between the adjacent magnetic poles via the armature, it is not necessary to wind the coil around all the magnetic poles. The magnetic pole may be formed or attached to an annular frame.

Further, in the above embodiment, as shown in FIG. 2, the hollow main shaft 5 for slidably supporting the piston 6 is provided.
Is cantilevered by the front casing 3,
This spindle may be supported at both ends.

FIG. 6 is a cross-sectional view of another embodiment of the present invention, in which the same reference numerals as those in FIG. 2 represent the same or equivalent parts. The main shaft 15 shown in FIG. 6 corresponds to the main shaft 5 in FIG. 2, but the rear end of the fluid passage 5A formed inside the main shaft 15 is closed and supported by the rear casing 4. ing. The fluid passage 5A
A rear end opening 15B is formed on the side surface of the rear end.
Also in this example, when the piston 6 reciprocates, the fluid flows through the fluid passage 5 through the air introduction opening 52 and the front end opening 15F.
A and is introduced into the casing through the rear end opening 15B.

When the main shaft 15 is supported at both ends, the main shaft 15 and the front casing 3 are supported.
When the rear casing 4 is made of a conductive material, a circulating current flows between the main shaft 15, the front casing 3 and the rear casing 4 due to the magnetic flux generated from the magnetic pole 1 when the coil is energized. Therefore, in this case, the main shaft 15, the front casing 3, and the rear casing 4
It is good to arrange an electrical insulating material between any of the above. In the example of FIG. 6, an insulator 16 is disposed between the magnetic pole 1 and the rear casing 4.

Since the present invention basically has an even number of four or more magnetic poles of the electromagnet, any other structure, for example, support of the piston, may be of any type. . That is, in the above embodiment, the piston 6 is described as being slidably supported by the hollow main shaft 5 or the main shaft 15, but instead of providing the main shaft, for example, the rear outer peripheral portion of the piston is slidably supported. Alternatively, the support portion and the cylinder 3A may support the front and rear portions of the piston.

When the piston 6 is supported by using the hollow main shaft to cool the inside of the casing, the fluid may be introduced into the casing when the fluid is discharged from the pressure chamber to perform cooling. In this case, the fluid introduced into the casing is discharged to the outside via the hollow main shaft.

[0041]

Advantages of the Invention (1) According to the electromagnetic reciprocating pump of the first aspect, the inner diameter of the armature can be increased, so that the weight of the armature is reduced. Although the number of magnetic poles is larger than that of the conventional magnetic pole, the cross-sectional area may be smaller than that of the conventional magnetic pole, so that the weight of the entire magnetic pole is not much different from that of the conventional magnetic pole. Therefore, the weight of the electromagnetic reciprocating pump is reduced. Conversely, if the weight is the same, a large capacity pump can be configured.

Further, by increasing the number of poles of the electromagnet, the attraction to the armature is dispersed, and the piston is less likely to be unevenly worn. As a result, the life of the piston is extended.

(2) In the electromagnetic reciprocating pump according to the second aspect, the thickness from the inner wall of the armature to the inner wall of the piston can be set relatively large, and the strength of the piston can be sufficiently obtained. .

Further, the diameter of the hollow main shaft supporting the piston can be increased, and the strength of the main shaft becomes sufficient. Further, since the inner diameter of the hollow main shaft also increases, the flow rate of fluid flowing into the casing of the pump through the main shaft increases, and the cooling efficiency of the pump increases.

Furthermore, it is possible to design so that the load value of the slide bearing disposed between the piston and the main shaft is appropriate, and wear of the bearing is reduced, which contributes to a longer life.

[Brief description of the drawings]

FIG. 1 is a side view of a field core and an armature according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of one embodiment of the present invention.

FIG. 3 is a diagram illustrating an example of an electric circuit according to an embodiment of the present invention.

FIG. 4 is a side view of the field core when two of the four magnetic poles are configured to be detachable from a frame of the field core.

FIG. 5 is a diagram showing a shape of a bobbin for winding a coil in a conical shape, and is a side view of the bobbin and a field core.

FIG. 6 is a cross-sectional view of another embodiment of the present invention.

FIG. 7 is a side view of a conventional field core and armature having two magnetic poles.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Magnetic pole, 2, 2A-2E ... Coil, 3 ... Front casing, 4 ... Rear casing, 5, 15 ... Main shaft, 5A ... Fluid passage, 5B, 15B ... Rear end opening, 5F, 15F ... Front end opening, 6 ... Piston, 8 ... Armature, 9 ... Compression coil spring, 85, 86, 87 ... Bobbin, 100, 200 ... Field core, 201 ... Frame, 202 ... Magnetic pole, 203 ... Magnetic pole, 203A ... Convex part, 204 ... Concave part

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F04B 35/04

Claims (1)

(57) [Scope of request for utility model registration] A casing having a cylinder, a piston head at one end thereof, a piston disposed in the casing such that the piston head can reciprocate in the cylinder, A fixed armature; spring means disposed between the piston and the casing for biasing the piston in one direction; and an armature which is inserted into the casing so as to suck the armature in a direction opposite to the biasing force of the spring means. A fixed electromagnet, provided in a pressure chamber formed by the cylinder inner wall and the piston head, sucks a fluid into the pressure chamber by reciprocating the piston, and discharges the sucked fluid. An electromagnetic reciprocating pump including a suction valve, a discharge port, and a discharge valve, wherein the electromagnet includes the armature. A coil is wound around the outside of the armature so as to form an even number of magnetic poles of four or more, and between adjacent magnetic poles, a magnetic flux forms a closed loop through the armature, and the casing has at least one end fixed. Hollow
A shaft having a through-hole in the axial direction.
The stone is fitted reciprocally via a bearing.
When the piston reciprocates, it moves out through the hollow main shaft.
Air flows through the casing, the bearings and the electromagnets
Or after cooling the armature, etc.
An electromagnetic reciprocating pump characterized by being introduced into a power chamber .