JP2002276555A - Small-sized pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the consumption of electric power in a small-sized pump by improving the efficiency of the motion of the pump. SOLUTION: The small-sized pump 21 has plural diaphragms 24 for forming a pump room 21 in a housing 22. Each diaphragm 24 is interlocked with an oscillating element 26 inclined and oscillates with an eccentric axis of rotation 30, and the diaphragm 24 moves upward/downward alternately, interlocking with the oscillation motion of the oscillating element 26 to make the pumping motion. In the small-sized pump 21, the surface opposite to the diaphragm 24 in the pump room 23 is formed as an inclined surface 43 so that the surface can be closely in contact with the diaphragm 24 when air in the pump room 23 is compressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small pump, and more particularly to a small pump used for a blood pressure monitor or the like and using a diaphragm.

[0002]

2. Description of the Related Art A small pump of this type, which has been previously filed by the present applicant, will be described with reference to FIG. In the figure 1
Denotes a small pump. In the small pump 1, pump chambers 3, 3 are formed in a case 2 which is rectangular in a plan view, and the diaphragms 4, 4 exhaust the pump chambers 3, 3. The diaphragms 4, 4 are provided with flanges 4a, 4 provided at the ends.
a is fitted and fixed to the case 2. Further, a disk-shaped oscillating body 5 is disposed on the lower surfaces of the diaphragms 4, 4, and the oscillating body 5 is in close contact with the lower surfaces of the diaphragms 4, 4.

[0003] Further, air introducing holes 6 and 6 are formed in the oscillating body 5.
Are formed in the air introduction holes 6, 6 to form suction valve portions 7, 7. The opening and closing operations of the suction valve portions 7, 7 allow the pump chambers 3, 3 to pass through the air introduction holes 6, 6. It is configured such that air can be introduced or blocked therein. An eccentric rotating shaft 8 that rotates in a tilted state by driving a motor is fixed to the center of the oscillating body 5, and a lower end of the eccentric rotating shaft 8 is a rotating body 9 disposed below the oscillating body 5. And the upper end of the eccentric rotary shaft 8 is supported by a shaft support 2 a provided at the center of the case 2. Since the rotating body 9 is rotated by driving the motor 10, the swinging body 5 swings while tilting back and forth and right and left.

[0004] An exhaust hole 11 communicating with the pump chambers 3 and 3 is formed in the upper center of the case 2.
In the upper part of the pump chambers 3, 3, annular grooves 12, 12 communicating with the exhaust holes 11 are provided. And the annular groove 1
Exhaust valves 13, 13 formed by extending the diaphragms 4, 4 on the inner wall surfaces of the pump chambers 3, 3,
Is formed to be openable and closable to the outside. Reference numeral 14
Denotes a motor case accommodating the motor 10;
Is a communication hole communicating the motor case 13 with the case 2; and 16 is an intake hole provided in the motor case 13 for sucking outside air.

When the motor 10 is driven, the rotating body 9 rotates, and the eccentric rotating shaft 8 of the rocking body 5 rotates eccentrically with the rotation of the rotating body 9. Therefore, since the swinging body 5 swings in an inclined state, the diaphragms 4, 4
Will alternately move up and down following the swing of the swing body 5.

Therefore, for example, one of the diaphragms 4
When the lower surface (left side in FIG. 2) is lowered, the inside of the pump chamber 3 on the diaphragm 4 side is in a negative pressure state, so that the exhaust valve 13 communicates with the exhaust hole 11 and the annular groove 12. The pump chamber 3 is closed in close contact with the side wall on which the pump is not performed. Further, the suction valve section 7 is naturally opened by the negative pressure state in the pump chamber 3, and air is sucked into the pump chamber 3 through the air introduction hole 6.

[0007] As shown in the figure, when the lower surface of the other diaphragm 4 rises, the air in the pump chamber 3 is compressed to a high pressure. At the same time, the introduction hole 6 is closed, and the other exhaust valve 13 turns to the side wall on the side where the annular groove 12 and the exhaust hole 11 can communicate with each other to open the exhaust hole 11. Therefore, the air in the pump chamber 3 is pressed out from the exhaust hole 11. As described above, the pump chambers 3 and 4 act by the action of the left and right diaphragms 4 and 4.
The operation of sucking and discharging the air into the inside 3 is performed, and the air is sent to the blood pressure monitor and the like.

[0008]

The above-mentioned small pump is
The pump is operated by alternately moving the diaphragm up and down while swinging the swinging body in an inclined state. However, when compressing the air in the pump chamber, the diaphragm in close contact with the oscillating body also compresses the air in the pump chamber in an inclined state, so that the diaphragm above the pump chamber facing the diaphragm is compressed. A gap S is generated between the inner surface and the inner surface. Therefore, as described above, when the diaphragm swings upward and discharges the air in the pump chamber from the exhaust hole, air remains in the gap S as much as possible. As a result, a loss occurs in the air discharge amount.

In order to solve this problem, it is necessary to prevent the air from remaining in the pump chamber when the air in the pump chamber of the small pump is compressed, to reduce the loss of the discharge amount of the pump, and to obtain an efficient small pump. A technical problem arises, and an object of the present invention is to solve the problem.

[0010]

SUMMARY OF THE INVENTION The present invention has been proposed to achieve the above object, and includes a plurality of diaphragms forming a pump chamber in a case, each of the diaphragms being inclined by an eccentric rotation axis. When the air in the pump chamber is compressed in a small pump that is interlocked with the oscillating body and that performs a pump operation by alternately moving the diaphragm up and down in conjunction with the oscillating operation of the oscillating body. An object of the present invention is to provide a small-sized pump in which a surface of the pump chamber facing the diaphragm is formed on an inclined surface so that the surface can be in close contact with the diaphragm.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIG. In the figure, reference numeral 21 denotes a small pump. The small pump 21 has two diaphragms 2 forming pump chambers 23, 23 in a rectangular case 22 in a plan view.
At the center of the lower part of the diaphragms 24, hollow mounting bodies 25 are projected downward.

Below the diaphragms 24, 24, there is provided an oscillating body 26 for vertically moving the lower surfaces of the diaphragms 24, 24. The case 22 is composed of an upper case 22a, a middle case 22b, and a lower case 22c in three stages. The diaphragms 24, 24 have flanges 24a, 24a... Of the upper case 22a. It is sandwiched between the lower case 22 c and held by the case 22.

The shafts 27, 27 having air introduction holes 27a, 27a, which are located in the vicinity of the periphery of the oscillating body 26 and below the respective centers of the diaphragms 24, 24, are raised. The shafts 27, 2
7, the inner surfaces of the hollow attachment bodies 25, 25 provided on the diaphragms 24, 24 are tightly fitted to each other,
Diaphragms 24, 24 are attached to the.

The bottom central portions of the respective diaphragms 24, 24 are cut out to form intake valves 28, 28, and the cutouts form through holes 29, 29. Then, through holes 29, 2 are formed by the intake valves 28, 28.
9 is formed so as to be able to close and open. The intake valve 2
The method of forming 8, 28 is not limited to the above-described method by incision, but can be formed by other methods.

Further, an eccentric rotation shaft 30 for oscillating the oscillating body 26 by eccentric rotation is fixed to the center of the oscillating body 26. A shaft support 31 extending from the middle case 22b is provided above the rocking body 26, and a recess 32 is formed below the shaft support 31 so as to open downward. Further, a rotating body 34 is fixed to the upper end of the rotating drive shaft 33 disposed on the lower side of the lower case 22c, and a concave portion 35 is formed in a peripheral portion above the rotating body 34. Thus, the upper end of the eccentric rotary shaft 30 is loosely fitted in the recess 32, and the lower end is loosely fitted in the recess 35.

On the other hand, an exhaust hole 36 is formed in the center of the upper case 22a, and the upper case 22a is connected to the exhaust hole 36 and has a lower portion opened to the pump chambers 23, 23. Grooves 37, 37 are formed. And
Exhaust valves 38, 38 having the ends of the diaphragms 24, 24 extending upward are pressed against the inner side surfaces 37a, 37a of the annular grooves 37, 37.

A motor case 40 for housing a motor 39 connected to the rotary drive shaft 33 is directly connected to the lower case 22c, and the lower case 22c communicates with the motor case 40 below the motor case 40. Communicating hole 4
1, and at least one intake hole 42 for introducing outside air into the motor case is formed in a lower portion of the motor case 40.

Further, the lower surface of the ceiling wall 22d of the case 22 forming the pump chambers 23, 23, which faces the diaphragms 24, 24, is provided when the diaphragm 24 swings upward. The inclined surfaces 43, 43 are provided so as to make almost surface contact with the inclined surfaces. That is, the diaphragm 24 of the pump chamber 23 swings upward in accordance with the swing of the swing body 26, and compresses the air in the pump chamber 23 through the exhaust hole 36 so that the air in the pump chamber is removed. When air is pressed out, the diaphragm 24 and the inclined surface 43 of the ceiling wall 22d are formed so as to be in close contact with each other, so that no air remains in the pump chamber 23.

Then, by driving the motor 39, the eccentric rotary shaft 30 is linked with the rotary drive shaft 33.
Is eccentrically rotated, so that the swinging body 26 swings while tilting, and moves the lower surfaces of the diaphragms 24, 24 up and down.
For example, when the lower surface of one of the diaphragms 24 is lowered, the exhaust valve 38 comes into close contact with the inner surface 37 a of the annular groove 37 and closes the exhaust hole 36 due to the negative pressure in the pump chamber 23. Further, the intake valve 28 opens to open the through hole 29 from the closed state. Therefore,
Arrow C from the air introduction hole 27a into the pump chamber 23
The intake is performed as shown in FIG.

On the other hand, when the diaphragm 24 rises, the air pressure in the pump chamber 23 rises and the intake valve 28
Closes the through hole 29. In addition, the exhaust valve 38 expands in diameter from the inner side surface 27a, and the exhaust hole 36 and the pump chamber 2
And 3. Therefore, exhaust is performed as indicated by arrow D.

At this time, since the diaphragm 24 and the inclined surface 43 formed on the lower surface of the ceiling wall 22a are in close contact with each other, residual air in the pump chamber 23 is reduced as much as possible. Thus, the efficiency of the compression operation is improved, and the compression time can be reduced.

Further, as the diaphragm 24 rises, the inside of the lower case 22c enters a negative pressure state, and the communication hole 4
1, the air in the motor case 40 flows in as shown by the arrow E, so that the inside of the motor case 40 is in a negative pressure state, and the outside air is sucked in through the intake hole 42 as shown by the arrow F.

The present invention can be variously modified without departing from the spirit of the present invention, and it is natural that the present invention extends to the modified ones.

[0024]

As described in detail in the above embodiment, the present invention provides a small pump in which a plurality of diaphragms accommodated in a case are alternately moved up and down in conjunction with an oscillating body to perform a pump operation. In the above, when each diaphragm compresses the air in the corresponding pump chamber, the diaphragm is in close contact with the inclined surface formed on the upper surface of the pump chamber facing the diaphragm, so that the air in the pump is as much as possible. The pump can be operated very efficiently because all the air in the pump chamber can be discharged instantaneously, and the compression time can be shortened, the power consumption can be reduced, and the quality can be improved. It is an invention which has a truly remarkable effect, for example, it can also contribute to the above.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a miniature pump showing one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a conventional small pump.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Small pump 22 Case 22d Ceiling wall 23 Pump room 24 Diaphragm 26 Oscillator 30 Eccentric rotation shaft 43 Inclined surface

Claims (1)

[Claims] A plurality of diaphragms forming a pump chamber are provided in a case, and each diaphragm is interlocked with an oscillating body which is inclined and oscillated by an eccentric rotation shaft, and is interlocked with the oscillating operation of the oscillating body. In a small-sized pump in which a diaphragm is alternately moved up and down to perform a pump operation, when the air in the pump chamber is compressed, the surface of the pump chamber facing the diaphragm is inclined so that it can be in close contact with the diaphragm. A small pump characterized by being formed.