JPH0421076B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a moving magnet diaphragm pump. More specifically, by reciprocating the vibrator through magnetic interaction between a vibrator connected to the diaphragm and an electromagnetic coil provided on the outer periphery of the vibrator, the diaphragm linked to the vibrator is caused to reciprocate. This is a movable magnet diaphragm pump that sucks and then discharges fluid in conjunction with this movement, and both ends of the state core are bent outward in the axial direction, so that the state core does not move when reciprocating. There is no adsorption or contact with the magnetic shoe provided on the vibrator, and the magnetic force is effectively applied in the axial direction up to the top and bottom dead centers of the vibration, improving pump performance. Regarding the state core that can be done. Note that the top dead center and bottom dead center here refer to the right diaphragm (first
For example, the time when the vibrator moves to the right is the top dead center, and the time when the vibrator moves to the left is the bottom dead center.

The movable magnet diaphragm pump of the present invention is mainly used for oxygen supplementation in fish tanks, garden ponds, or human waste septic tanks, or for sampling test gas in pollution monitoring.

[Conventional technology]

Conventionally, there is a movable magnet type diaphragm pump described in Japanese Patent Application Laid-open No. 54-84603 (see FIG. 7).

Such a diaphragm pump has a cylindrical yoke 2
The vibrator 23 is caused to reciprocate in its axial direction by magnetic interaction between the inner circumferential end of the vibrator 1 and the N and S magnetic poles generated at both ends of the vibrator 23. N and S in FIG. 7 indicate the polarities of the magnetic poles appearing at the inner peripheral end of the yoke 21 during a certain half wave of the alternating current, and in this case the vibrator 23 is moved to the right. During the next half wave, the magnetism becomes N and S, and the vibrator is moved to the left. In this way, the vibrator 23 vibrates in the left-right direction in synchronization with the cycle of the applied alternating current, and the diaphragms 26a and 26b also vibrate in conjunction with this. and the right side of diaphragm 26a and diaphragm 26b
The diaphragm pump is operated by applying regular pressure fluctuations to the fluid in a working chamber (not shown) provided on the left side of the diaphragm pump, sucking the fluid into the working chamber, and discharging the fluid outside the working chamber. functions as a pump.

However, in the conventional diaphragm pump, it is necessary to increase the permeance coefficient of the magnet in order to strengthen the residual magnetic flux of the permanent magnet 24, which is made of a cast magnet attached to the support shaft 25. A permanent magnet is used, and the permanent magnet 24 is used to strengthen the magnetic force between the magnetic poles generated at the inner circumferential ends of the left and right ends of the yoke 21 and the S and N poles of the permanent magnet 24. Since the magnetic pole pieces 27a and 27b are provided on the left and right end faces of the vibrator 23, the weight of the vibrator 23 becomes very large.

Therefore, the natural frequency of the vibrator 23, which is determined by the design conditions of the diaphragm or the weight of the vibrator 23, cannot be made to match the frequency of the alternating current flowing through the electromagnetic coils 22a and 22b. Therefore, there is a problem in that the discharge capacity of the diaphragm pump cannot be rapidly increased due to resonance between alternating changes in the alternating current and the vibration of the vibrator, resulting in poor driving efficiency of the diaphragm pump.

In order to effectively solve the above problems,
As already described in the specification of Japanese Patent Application No. 61-208423 (Japanese Unexamined Patent Publication No. 63-65182), the applicant has proposed that We proposed a movable magnet diaphragm pump equipped with two separate ferrite magnets whose magnetic poles on opposite sides have the same polarity.
Furthermore, the specification of Japanese Patent Application No. 1983-8380
As described in Japanese Patent No. 176680, a magnetic field is used to form an active magnetic field with a high magnetic flux density between an electromagnetic coil and a magnet, thereby increasing the vibrating force of the vibrator and increasing the pump's discharge capacity. We are proposing a diaphragm pump that is equipped with a

[Problem that the invention seeks to solve]

However, even the method described in the specification of Japanese Patent Application No. 62-8380 (Japanese Unexamined Patent Publication No. 176680/1983) has the following problems.

8-9 show the right half of the vibrator 109 and the state core 108, and the right diaphragm 1.
11, in which the yoke plate core, side plates, etc. are omitted for simplicity. 107a, 107b, 107c are
It is a magnetic shoe made of isotropic magnetic material such as silicon steel plate, and as shown in Figures 8 and 9, its peripheral edge is bent in order to increase the magnetic flux density in the magnetic circuit and increase the magnetic force. It is fixedly provided to the ferrite magnet 105.

The vibrator 109 in FIG. 8 is in a so-called neutral state, not moving to the right or left, and the core of the vibrator 109 and the core of the state core 108 are approximately aligned. And vibrator 1
When the electromagnetic coil is energized to vibrate left and right 09, an axial force F _L ' is generated by the magnetic fluxes A', B', and C' as shown in FIG. It becomes drawn into the core 108. In the above description, it is assumed that the polarity S first appears at the right end of the state core 108 upon energization.

Thereafter, with the passage of time (time within a half wave with alternating current), the vibrator 109
It gradually moves to the left due to the action of F _L ', but in this case, as shown in FIG.
When they begin to overlap, the force due to the magnetic fluxes A', B', and C' changes to a force that attracts the magnetic shoe 107a to the state core 108 like Fv'. This force Fv' gradually increases as the vibrator 109 moves to the left. In that case,
The core of the vibrator 109 and the core of the state core 108 are completely aligned, and the force of the rubber diaphragm supporting the vibrator 109 is in all directions.
In other words, there is no problem if it is equal in all directions of 360° with respect to the axis 106 of the vibrator 109.
In practice it is very difficult to match the cores perfectly and to obtain a completely homogeneous diaphragm. As a result, the rubber diaphragm supporting the central position of the vibrator 109, that is, the magnetic shoe 107a, becomes sagging in one area, and the opposite side is stretched, resulting in deviation. Even if the magnetic shoe 107a is not attracted to the state core 108 even in this biased state at the beginning of operation, as the operation continues, the bias is amplified.
Eventually, the adsorption force becomes greater than the tensile strength of the rubber, and the magnetic shoe 107a comes into contact with and adsorbs to the state core 108.

When the vibrator 109 is moved to the maximum extent, the tensile strength of the rubber is large, so it is possible to counteract the adsorption force and support the vibrator 109 at the center position, but when the diaphragm 111 is in the vicinity of the neutral state, Since the tensile strength of rubber is small, even a slight adsorption force causes the diaphragm to shift.

And, as mentioned above, the magnetic show 10
If 7a comes into contact with the state core 108, the vibration of the vibrator 109 from side to side will be restricted, and the performance of the pump, that is, the discharge capacity will be significantly reduced. Furthermore, a problem arises in that impact noise and vibration occur, and the magnet shoe 107a and state core 108 are eventually damaged, rendering the pump useless as a pump.

In order to prevent the above-mentioned inconveniences, the difference between the inner diameter of the state core and the outer diameter of the magnet shoe may be increased to reduce the adsorption force.
In this case, the magnetic attraction forces that act on each other become weaker, and the vibration force of the vibrator becomes smaller, causing another problem in that the performance of the pump is significantly reduced.

The present invention has been made to solve the above-mentioned problems, and it not only prevents contact between the magnet shoe and the state core, but also prevents the magnetic shoe from coming into contact with the state core. (process up to)
It is an object of the present invention to provide a movable magnet type diaphragm pump that can effectively apply magnetic force in the axial direction.

[Means for solving problems]

The movable magnet diaphragm pump of the present invention is equipped with an electromagnetic coil and a vibrator that is inserted into the electromagnetic coil, connected to the diaphragm, and provided with a pair of permanent magnets. In a diaphragm pump, in which the polarities of the magnetic poles in the axial direction on opposing sides of the first permanent magnet and the second permanent magnet provided spaced apart from each other in portions corresponding to the S and N poles of the electromagnetic coil are the same. A cylindrical state core made of a magnetic material is interposed between the electromagnetic coil and the vibrator, and both ends of the state core are bent outward in the axial direction.

〔Example〕

Next, the movable magnet type diaphragm pump of the present invention will be explained based on drawings showing embodiments thereof.

FIG. 1 is a partial sectional view of a movable magnet type diaphragm pump with a discharge rate of about 10 per minute, according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an electromagnetic coil having a donut-shaped cross section, and a conducting wire is wound around a hollow portion formed in the center of the electromagnetic coil. A cylindrical yoke core 3 is provided on the outer periphery of the electromagnetic coil 1 so as to cover the electromagnetic coil 1 and share a central axis with the electromagnetic coil 1.

On the inner periphery of the electromagnetic coil 1 and on both end faces of the left and right sides shown in Fig. 1 (hereinafter left, right, top, and bottom refer to those in Fig. 1), there are longitudinal sections in contact with this. A bobbin 2 whose upper and lower halves are U-shaped is provided. A donut-shaped right yoke plate core 4 and a left yoke plate core 4' are fixed on both the left and right end surfaces of the bobbin 2 in contact with them, respectively. The yoke plate cores 4, 4' protrude slightly from the inner peripheral surface of the bobbin 2 in the direction of the central axis. A support shaft 6 for a vibrator (described later) is provided at the center axis of the electromagnetic coil 1 and extends in the direction of the center axis. The parts corresponding to the right side of the short cylinder are respectively
A permanent magnet 5 (hereinafter simply referred to as a first magnet) and a second magnet 5' on the left side (hereinafter simply referred to as a second magnet) are fixed and spaced apart by appropriate means.

The central axes of the first magnet 5 and the second magnet 5' coincide with the central axis of the support shaft 6. Furthermore, the polarities of the magnetic poles in the axial direction of the opposing surfaces of the first magnet 5 and the second magnet 5' are both S poles, and therefore the polarities of the magnetic poles on these opposite surfaces are N.
It has become a pole. and the first magnet 5 and the second
On both the left and right end surfaces of each of the magnets 5', in contact with them, there is a magnet sheet made of several laminated disc-shaped silicon steel plates, each of which is a magnetic material and has a thickness of 0.5 mm. You 7a, 7b, 7c, 7a', 7
b' and 7c' are fixedly provided by appropriate means.

The outer peripheral end of the magnetic shoe is bent along the outer peripheral end surface of the ferrite magnet. That is, magnetic shoes 7b, 7c, 7b', 7
The peripheral end of c' is made of ferrite magnets 5 and 5', respectively.
It is bent at right angles along and in contact with the outer circumferential end surface of the ferrite magnets 5, 5', and extends slightly from the left or right end surface of each of the ferrite magnets 5, 5'.

Also, on the left side surface of the magnetic shoe 7b and on the right side surface of the magnetic shoe 7b', a magnetic shoe 7a and a magnetic shoe 7a' similar to the magnetic shoes 7b, 7c, 7b', and 7c' are placed in contact with these. are fixedly provided, and the peripheral ends of the magnetic shoes 7a, 7b are bent inward at right angles so that these peripheral ends approach the state core 8.

Magnetic shoes 7a, 7b, 7c, 7a', 7
The dimensions of the perpendicularly bent peripheral edges of b' and 7c' are:
Although it is determined by design conditions such as the discharge capacity of the pump and the moving distance of the vibrator 9, the magnetic shoe 7b
It is necessary to prevent the peripheral end surfaces of the magnetic shoes 7c and the magnetic shoes 7b' and 7c' from becoming magnetically short circuits. In this embodiment, the dimension of this peripheral end is 1 to 3 mm.

Due to such bending, the inner peripheral ends of the yoke plate cores 4, 4' and the magnetic shoes 7b, 7c,
The distance from the outer peripheral edge of 7b' and 7c' is shorter than when the magnetic shoe is flat, and the distance between the magnetic shoe 7 and the isotropic magnetic material is shorter than when the magnetic shoe is flat.
The magnetic path formed by b, 7c, 7b', 7c' becomes longer. As a result, the inner peripheral ends of the yoke plate cores 4, 4' and the magnetic shoe 7
b, 7c, 7b', and 7c' are increased, and the magnetic resistance of the magnetic circuit can be further reduced, so that the magnetic flux density in the magnetic circuit can be increased and the magnetic force can be increased. A gap of approximately 1 mm to 3 mm is formed between the outer peripheral surface of the magnetic shoe and the inner peripheral surface of the yoke plate cores 4, 4'. The support shaft 6, the first and second magnets 5, 5', and the magnetic shoes 7a, 7b, 7c,
A vibrator 10 is constituted by 7a', 7b', and 7c'. Furthermore, a cylindrical state core 8 is provided on the inner periphery of the bobbin 2 at approximately the center thereof, with its center axis coinciding with the center axis of the support shaft 6. The state core 8 is fixed on the inner circumferential surface of the bobbin 2 with its outer circumferential surface in contact with the inner circumferential surface of the bobbin 2, and the inner circumferential surface of the state core 8 is connected to the yoke plate core 4,
It is substantially flush with the inner peripheral end surface of 4'. 10,
10' is a diaphragm stand that supports the diaphragms 11, 11'. Both ends of the support shaft 6 pass through the center of the diaphragm stands 10, 10' and protrude outward. A casing member 12 in which a suction chamber 12a, a discharge chamber 12b, and a recess 12c are formed is fixed to the right end surface of the diaphragm stand 10, and a suction chamber 12a' and a discharge chamber 12b are fixed to the left end surface of the diaphragm stand 10'. A casing member 12' in which a recess 12c' and a recess 12c' are formed is fixed. A substantially disc-shaped diaphragm 11 made of EPDM is provided between the diaphragm stand 10 and the casing member 12, with its peripheral end fitted between the diaphragm stand 10 and the casing member 12. Further, the right end portion of the support shaft 6 passes through the center of the diaphragm 11, and the diaphragm 11
Center plates 13, 13 for pushing and pulling the diaphragm 11 to displace it left and right are provided on both sides of the diaphragm 11. The diaphragm 11 and the center plates 13, 13 are interposed between the mounting seat 14 and the nut 15, and are fixed on the right end of the support shaft 6 by being tightened by the nut 15. The diaphragm 11 and the recess 12c of the casing member 12 define an operating chamber.

The casing member 12 is provided with a suction port 12d communicating with the suction chamber 12a and a discharge port 12e communicating with the discharge chamber 12b.
A suction valve 16 is provided in the communication hole 12f provided in the partition between the working chamber and the discharge chamber 12b, and a discharge valve 17 is provided in the communication hole 12g provided in the partition between the working chamber and the discharge chamber 12b. ing.

The configuration on the left side of the diaphragm mount 10' is completely symmetrical and the same as the configuration on the right side of the diaphragm mount 10.

Next, the function and operation of the diaphragm pump shown in FIG. 1 will be explained.

When an alternating current is passed through the electromagnetic coil 1, N and S magnetic poles are alternately generated at both ends of the electromagnetic coil 1 in synchronization with changes in the alternating current. Therefore, the yoke plate cores 4, 4' are magnetic.
The magnets are also magnetized in synchronization with changes in the alternating current, and magnetic poles of different polarities appear alternately at the inner peripheral end of the yoke plate core 4 and the inner peripheral end of the yoke plate core 4'. That is, the inner circumferential end of the yoke plate core 4' becomes the S pole or the N pole corresponding to the inner circumferential end of the yoke plate core 4 becoming the N pole or the S pole.

Here, if the inner circumferential end of the yoke plate core 4 is magnetized to the S pole during a half-wave with alternating current, the inner circumferential end of the yoke plate core 4' is magnetized to the N pole.
In this case, the S pole at the inner peripheral end of the yoke plate core 4 is attracted to the N pole of the magnet shoe 7c, which is magnetized by the first magnet 5. 5 exerts a repulsive interaction with the S poles of the magnetic shoes 7a and 7b magnetized by the magnets 5. Also, N of the inner peripheral end of the yoke plate core 4'
The N pole of the magnetic shoe 7c magnetized by the second magnet 5' is a repulsive force, and the S pole of the magnetic shoes 7a' and 7b' magnetized by the second magnet 5' is a repulsive force. exerts an interaction of attraction. As a result, the vibrator 9 receives a leftward force and moves to the left. Next, when the alternating current changes to the next half-wave between the above-mentioned half-waves, the inner circumferential end of the yoke plate core 4 is magnetized to the north pole, and at the same time, the inner circumferential end of the yoke plate core 4' is magnetized to the south pole. magnetized. In this case, the magnetic poles at the inner peripheral ends of the yoke plate core 4 and the yoke plate core 4 are the same as the magnetic poles of the magnetic shoes 7a, 7b, 7c and the magnetic shoes 7a', 7b', 7c'. In the case of waves, a completely opposite interaction occurs and the oscillator 9 moves to the right.

Note that the magnet shoes 7a, 7b, 7 made of magnetic material
By providing magnets c, 7a', 7b', and 7c', most of the lines of magnetic force generated by the first and second magnets 5, 5' are collected at the peripheral ends of these magnets, so that the yoke plate core 4 and the yoke are Plate core 4'
magnetic poles and magnetic shoes 7a, 7b,
7c and the magnetic poles of magnet shoes 7a', 7b', and 7c' become very strong.

In this way, the vibrator 9 vibrates back and forth in the left-right direction in synchronization with the cycle of the alternating current, and in conjunction with this, the diaphragm 11 vibrates left and right. When the vibrator 9 moves to the left, the suction valve 16 opens while the discharge valve 17 remains closed, and the fluid sucked into the suction chamber 12a by the suction port 12b flows into the working chamber through the communication port 12f. Next, when the vibrator 9 moves to the right, the suction valve 16 closes and the discharge valve 17 opens, allowing the fluid in the working chamber to be discharged from the discharge port 12e via the communication port 12g, the discharge chamber 12b, and the discharge port 12e. The same operation as described above is performed for the left side of the diaphragm stand 10', and in this way the movable magnet type diaphragm pump shown in FIG. 1 is driven.

The state core 8 according to the present invention is used in a movable magnet diaphragm pump having the configuration and operation as described above, and as described above,
It is characterized in that both ends thereof are bent outward in the axial direction.

Hereinafter, the state core 8 in the present invention will be explained in detail.

FIG. 2 is a schematic perspective view of one embodiment of the state core of the present invention, and FIG. 3 is a schematic perspective view of another embodiment of the state core of the present invention.

The one shown in FIG. 2 is a single-layer silicon steel plate with a thickness of about 2 mm that is formed so that some slits are formed, that is, the cross section is C-shaped. The one shown in FIG. 3 is a 0.3 mm silicon steel plate spirally wound to have a total thickness of about 2 mm.

The device shown in FIG. 2 has the feature that it can prevent the generation of secondary current because the entire structure is an open circuit against the electromotive force generated in the magnetic body in a direction perpendicular to the direction in which the magnetic flux passes. Furthermore, since the structure shown in Figure 3 has a structure in which thin plates are laminated, it is possible to prevent eddy currents from occurring inside the state core, and the entire structure is an open circuit like the one shown in Figure 2. Therefore, generation of secondary current can also be prevented.

Furthermore, silicon steel sheets made by adding Si to Fe have the characteristics of low residual magnetization and low hysteresis loss, so that energy loss in the magnetic circuit that occurs when alternating current is passed through the electromagnetic coil 1 is reduced. will also become smaller.

For this reason, the energy loss within the state core is reduced and the amount of heat generated is also reduced, and the heat generated by the diaphragm pump itself can also be reduced.

The thickness of the silicon steel plate is not limited to the above value, and the material is not limited to the silicon steel mentioned above; any steel with any composition can be used as long as it can reduce residual magnetization. .

The state core according to the present invention may have a shape in which both ends thereof are simply bent outward in the axial direction as shown in FIG. It is also possible to form a stepped portion that becomes thinner toward the end. In short, the state core according to the present invention is characterized in that both ends thereof are bent outward in the axial direction, and there are no particular limitations on the external shape of the state core. Therefore, end state cores as shown in FIG. 4c, for example, are also included in the present invention.

When creating a state core with a slope,
It may be made by bending a thin plate with an inclined portion formed in advance into a cylindrical shape, or the inclined portion may be processed after forming the thin plate into a cylindrical shape. The thing shown in Fig. 3 is obtained by winding a strip-shaped thin plate in a helical pattern. can also be formed.

The state core may be made of one part, for example, as shown in Figure 2, but when using a state core with an outwardly bent end as shown in Figures 4a to 4c, manufacturing and assembly are required. 2 parts (2 parts in the direction orthogonal to the axis of the state core)
It is also possible to make it into three parts (a central part with constant inner and outer diameters and openings at both ends).

Next, the operation of the state core in the present invention will be explained.

5 and 6 show the oscillator 9 and the state core 8.
FIG. 2 is a schematic explanatory diagram showing the right half of the diaphragm 11 and the right diaphragm 11 .

As shown in FIG. 5, when the vibrator 9 is in a neutral state of left-right vibration, that is, when the center holding force of the diaphragm 11 is weak, the entrance of the state core 8 is inclined, and the state core 8 and the magnet Since the distance between the state core 8 and the magnet shoe 7a can be made large, the magnetic fluxes A, B, and C can be directed in the axial direction and concentrated as the axial force F _L , and the magnet shoe 7a can be attracted to the state core 8. power to
Fv can be made as small as possible. When the amplitude of the vibrator 9 advances and reaches the state shown in FIG. 6, the diaphragm is stretched and the tensile strength of the rubber is at its maximum, so the force holding the vibrator 9 at the center is very strong, and the state core 8 Even if the magnetic shoes A, B, and C become quite close to each other internally and the attraction force Fv by A, B, and C becomes strong, the state core 8 and the magnetic shoe 7a do not come into contact with each other. As shown in Fig. 6, even when the vibrator 9 is swung considerably to the left, the axial component of force caused by A, B, and C is large, so the resultant force F _L is at the bottom dead center of the vibration. It works reliably in the axial direction until the end of the pump, allowing the pump to exhibit its maximum performance.

〔Effect of the invention〕

As explained above, since both ends of the state core of the present invention are bent outward in the axial direction, the following effects can be achieved.

When the vibrator is in the neutral state of left-right vibration and the diaphragm's center holding force is weak, the distance between the state core and the magnet shoe can be made large, so the attraction force between them can be minimized.
It is possible to prevent the diaphragm from shifting.

If the adsorption force is kept small when the diaphragm's center holding force is weak, even if the oscillator moves and the state core and magnet shoe come close to each other and the magnetic attraction becomes strong, the diaphragm will stretch. Since the tensile strength of the rubber is at its maximum, the force holding the vibrator at the center is very strong, and therefore the state core and magnet shoe do not come into contact with each other.

When the surface of the state core where the magnetic flux enters is inclined, it is possible to obtain a component force in the axial direction during the entire swinging process (from top dead center to bottom dead center), so the magnetic action can be used effectively. , the performance (discharge capacity) of the pump can be increased.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a movable magnet diaphragm pump provided with an embodiment of the state core according to the present invention, FIG. 2 is a schematic perspective view of an embodiment of the state core according to the present invention, and FIG. A schematic perspective view of another embodiment of the state core in the invention, FIGS. 4a to 4c are explanatory diagrams of an embodiment of the state core in the invention, and FIGS. 5 to 6 show an embodiment of the state core in the invention and a magnetic shield. An explanatory diagram showing the relationship between the pump and the diaphragm, FIG. 7 is a sectional view of a conventional movable magnet diaphragm pump, and FIGS.
The figure is an explanatory view showing the relationship between a state core whose both ends are not bent outward in the axial direction, a magnet shoe, and a diaphragm. (Main symbols in the drawing) 1: Electromagnetic coil, 5: First magnet, 5': Second magnet, 6: Support shaft, 7a,
7b, 7c, 7a', 7b', 7c': Magnetic shoe, 8: State core, 9: Oscillator, 11, 1
1': Diaphragm.

Claims (1)

[Claims] 1. An electromagnetic coil, and an electromagnetic coil inserted into the electromagnetic coil,
a vibrator connected to a diaphragm and provided with a pair of permanent magnets; In a diaphragm pump in which the magnetic poles of the permanent magnet and the second permanent magnet have the same polarity in the axial direction on opposing sides, a cylindrical state core made of a magnetic material is interposed between the electromagnetic coil and the vibrator. A movable magnet diaphragm pump characterized in that both ends of the state core are bent outward in the axial direction. 2. The movable magnet diaphragm pump according to claim 1, wherein the state core is provided with sloped portions that slope toward the end faces on the inner surfaces of both ends thereof. 3. The movable magnet diaphragm pump according to claim 1, wherein stepped portions opening toward the end surfaces are provided on the inner surfaces of both ends of the state core.