JP2002005028A - Pumping unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pumping unit which is minimized in friction of moving parts structurally in supply and discharge working fluid switching mechanism, and can be improved in durability. SOLUTION: This pumping unit is equipped with a switching chamber 53 to receive pressurized working fluid in the working fluid switching mechanism 51 and an actuation rod 54, which reciprocates with diaphragms 32, 33 in the switching valve chamber 53 is inserted. A rotation support shaft 61 is provided in the crossing direction of an actuation rod 54, and perpendicular to the rotation support shaft 61 a fixed valve plate 62 is provided while having working fluid supply and discharge port which communicates switching valve chamber 53 to one of working fluid chambers 44, 45 and also having working fluid discharge port which communicates another working fluid chambers 44, 45 to outside. A rocking valve body 66 switches supply and discharge working fluid sliding to the fixed valve plate 62 while rocking around a supporting point of the rotating support shaft 61 in the switching chamber 53. A switch actuation 68 while switching the rocking valve body 66 engaging with the rocking valve body 66 in the process of rocking around the rotation support shaft 61 installed between the actuation rod 54 and the rocking valve body 66, and energized by spring 92.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump device characterized by a working fluid supply / discharge switching mechanism.

[0002]

2. Description of the Related Art As shown in FIG. 7, pump chambers 12 are formed on both left and right sides of a pump body 11 so as to face each other, and these left and right pump chambers 12 are formed on the left and right suction-side check valves 13. And a common discharge port 16 via left and right discharge-side check valves 15, and a partition 17 formed inside the left and right pump chambers 12 by a diaphragm 17. An air chamber 18 for working air is provided, and both ends of an operating rod 19 are fixed between the center portions of the diaphragms 17 on both sides, so that air supply and exhaust to the left and right air chambers 18 are switched between supply and exhaust of air. There is a pump device that alternately performs the suction and discharge operations of the left and right pump chambers 12 alternately in relation to the reciprocating motion of the operating rod 19 by means of 21.

The above-mentioned working air supply / exhaust switching mechanism 21 is provided with a switching valve chamber formed within the pump body 11 for receiving supply of working air.
At 22, a switching operator 23 is slidably and loosely fitted to the operating rod 19 within a certain axial range, and the switching operator 23 moves together with the operating rod 19 against the urging force of the spring 24 to neutralize. When the position exceeds the dead point, the position is instantaneously switched to the opposite switching position by the urging force of the spring 24. At this time, the switching operation is provided in the guide groove 25 of the switching operator 23 so as to be freely detachable. The switch 26 is also a guide groove for the pump cast body 11.
The slide is instantaneously slid within the switch 27 to perform the switching operation.
By the movement of 28, the air chamber 18 communicating with the switching valve chamber 22 is switched from one air chamber to the other air chamber, and the air chamber 18 exhausted outside is changed from the other air chamber to the one air chamber. I try to switch.

[0004]

The switching element 26 is guided by a spring member 29 provided between the rear surface (lower surface in the drawing) of the switching element 23 and the switching operation element 23, so that the guide groove 27 of the pump cast body 11 is provided.
When the switching operator 23 moves in the axial direction together with the operating rod 19, for example, when the switching operator 23 moves to the left, the right end of the guide groove 25 is connected to the switching element 26. The right end shoulder of the switch 26 is engaged with the left end leg of the switch 26 due to the sliding resistance received from the guide groove 27 of the pump body 11, so that the right end shoulder of the switch 26 has the left end leg as a fulcrum. The switch 26 reciprocates, and the legs at the left and right ends of the switch 26 are liable to wear due to sliding because the front is turned forward so that it floats against the spring member 29 and slides in a position where the front can not be pressed. , There is a problem that its function is gradually impaired.

The present invention has been made in view of the above points, and an object of the present invention is to provide a pump device capable of structurally reducing wear of a movable member in a working fluid supply / discharge switching mechanism and improving durability. It is assumed that.

[0006]

According to the first aspect of the present invention, a pump body, a variable volume member provided in the pump body, a pump chamber formed in the pump body by the variable volume member, A pumping chamber includes a working fluid chamber defined by a variable volume member, and a supply / discharge switching mechanism for switching the supply / discharge of the working fluid to / from the working fluid chamber by a swing valve body that swings around a rotation support shaft. Pump device
As a result, the swing valve body in the supply / discharge switching mechanism repeats a stable swinging motion about the rotation support shaft, so that the wear of the swing valve body is structurally reduced, and the durability of the supply / discharge switching mechanism is improved. Is improved.

According to a second aspect of the present invention, in the pump device according to the first aspect, the supply / discharge switching mechanism is provided inside the switching mechanism main body and the switching mechanism main body, and receives pressurized supply of the working fluid. A switching valve chamber, an operating rod inserted into the switching valve chamber and reciprocating integrally with the variable volume member, a rotation support shaft provided in a direction intersecting the operation rod, and a right angle to the rotation support shaft. A fixed valve plate provided with a working fluid supply / discharge port for communicating the switching valve chamber with the working fluid chamber and a working fluid discharge port for discharging the working fluid returned from the working fluid chamber to the outside;
Supplying the working fluid from the switching valve chamber to the working fluid chamber and discharging the working fluid from the working fluid chamber to the outside by sliding against the fixed valve plate while swinging about the rotation support shaft in the switching valve chamber. Between the operating rod and the oscillating valve element, and interlocks with the oscillating valve element while swinging around the pivot shaft as a fulcrum in conjunction with the reciprocating operation of the operating rod. When the switching operating body that switches the valve operating body and the switching operating body that swings in conjunction with the reciprocating operation of the operating rod exceeds the neutral position, the accumulated pressure is released and engaged with the switching operating body. And a spring for instantaneously switching the swinging valve body, whereby the swinging valve body in the working fluid supply / discharge switching mechanism swings around a rotation support shaft. The swing valve body swings in parallel with the fixed valve plate provided at right angles to the rotation support shaft. Wear of the oscillating valve body that is structurally less, there is no particular part of the uneven wear, and durability is improved. Furthermore, when the switching operating body that swings in conjunction with the reciprocating operation of the operating rod exceeds the neutral position, the force accumulated in the spring is released, and the swinging valve body engaged with the switching operating body is instantaneously released. By performing the switching operation, it is possible to prevent the occurrence of a trouble in which the swing valve body stops moving at the neutral position.

According to a third aspect of the present invention, in the pump device according to the first or second aspect, the variable volume member is a diaphragm, whereby a chemical product is provided in comparison with the case where the variable volume member is a piston. Suitable for pumping paints, inks, adhesives, oils, waste oils, filth, sludge, etc.

According to a fourth aspect of the present invention, in the pump device according to the third aspect, a pair of diaphragms are provided,
The operating rod connects between the pair of diaphragms, and the supply / discharge switching mechanism is disposed between a pair of working fluid chambers defined by the pair of diaphragms. By alternately repeating the suction and discharge of the pumping material and the suction and discharge of the pumping material by the other diaphragm, the efficiency of the pump action is increased.

According to a fifth aspect of the present invention, in the pump device according to any one of the second to fourth aspects, at least the fixed valve plate, the swing valve body, and the switching operation body are formed by a mold. Yes, thereby facilitating manufacturing.

According to a sixth aspect of the present invention, in the pump device according to the fifth aspect, at least the fixed valve plate, the swing valve body, and the switching operation body are formed of one of a sintered metal and a synthetic resin. In addition, since the swing valve body that slides with the fixed valve plate is structurally less worn, it is possible to obtain sufficient durability as a synthetic resin part that can be easily manufactured, and to use sintered metal. Molded articles are more durable and can maintain accuracy even when used frequently.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described.
This will be described with reference to FIGS.

As shown in FIG. 1, a pair of diaphragms 32 and 33 as a variable volume member are provided in a pump body 31.
A pair of pump chambers 34 and 35 are formed in 31 respectively. These pump chambers 34, 35 are provided with a pair of suction side check valves 3
It communicates with the common suction port 38 via 6, 37,
It is connected to a common discharge port 43 via a pair of discharge-side check valves 41 and 42.

A pair of working fluid chambers 44, 45 are defined by the respective diaphragms 32, 33 with respect to the pair of pump chambers 34, 35, and chamber members 46, 47 forming these working fluid chambers 44, 45 are formed. Between them, a supply / discharge switching mechanism 50 for switching supply / discharge of the working fluid to / from the working fluid chambers 44, 45 is disposed.
The working fluid uses compressed air supplied from a compressor or the like.

The switching mechanism 50 for supplying and discharging the working fluid will be described with reference to FIGS. 2 and 3. A switching valve chamber 53 which receives pressurized supply of the working fluid through a working fluid supply hole 52 is provided inside a switching mechanism main body 51. The switching valve chamber 53 is connected to the pair of diaphragms 32 and 33 to connect the diaphragms 32 and 33 to each other.
An operating rod 54 that reciprocates integrally with 33 is inserted.

As shown in FIG. 2, the opening of the switching valve chamber 53 has a cover body 55 fixed by screws 56 via a packing 55.
As shown in FIG. 3, the bearing 58, which is hermetically sealed by the bearing 57 and slidably holds the operating rod 54, is kept airtight by O-rings 59, 60 fitted on its inner and outer peripheral surfaces. I'm dripping.

Inside the switching valve chamber 53, a turning support shaft 61 with a screw is provided in a direction intersecting the operating rod 54,
A fixed valve plate 62 is provided at right angles to the rotation support shaft 61. As shown in FIG. 2, the fixed valve plate 62
A gasket 64 is fitted into a valve plate fitting groove 63 provided at the bottom of the valve 53, and is fixed by screws (not shown). As shown in FIG. 3, a pair of locking portions 65 are integrally provided. .

A pair of locking portions 65 are provided on the pivot 61.
A swinging valve body 66 that is swingable is rotatably fitted therebetween, and is further rotated within a limited range in the switching valve chamber 53 via a compression coil-shaped spring 67 shown in FIG. A movable switching operation body 68 is rotatably fitted.

The swing valve element 66 is provided in the switching valve chamber 53 with the pivot 61
Is supplied to the working fluid chamber 44 or 45 from the switching valve chamber 53 and is discharged from the working fluid chamber 45 or 44 to the outside. Is switched.

The switching operating member 68 is integrally provided with an engaging projection 70 which is provided between the operating rod 54 and the swing valve body 66 and is loosely fitted in the small-diameter groove 69 of the operating rod 54. Interlocking with the swing valve body 66 while swinging about the rotation support shaft 61 as a fulcrum in conjunction with the reciprocating operation of the operating rod 54 via the projection 70, the swing valve body 66
Is switched.

As shown in FIG. 4, the valve plate fitting groove 63 is provided.
The opening is provided with two working fluid supply / discharge holes 71 and 72 communicating with a pair of working fluid chambers 44 and 45, and one working fluid discharge hole 73 for discharging the working fluid to the outside. A screw hole 74 for screwing the moving support shaft 61 and a screw hole 75 for screwing a screw for fixing the fixed valve plate 62 are provided.

Further, a screw hole 76 for screwing a screw for fixing the chamber members 46 and 47 and a screw 56 for fixing the lid 57 are screwed into the switching mechanism main body 51. Screw holes 77 are provided.

As shown in FIG. 5, the fixed valve plate 62 includes
The switching valve chamber 53 is aligned with the working fluid supply / discharge holes 71 and 72 and the working fluid discharge hole 73 opened in the valve plate fitting groove 63, respectively.
Are provided with two working fluid supply / discharge ports 81 and 82 communicating with the working fluid chamber 44 or 45, and one working fluid discharge port 83 for discharging the working fluid returned from the working fluid chamber 45 or 44 to the outside. ing. Further, a screw insertion hole 84 for inserting a screw for fixing the fixed valve plate 62 is provided.

The oscillating valve body 66 is provided with a triangular switching groove 85 on a surface facing the fixed valve plate 62, and at the switching position of the oscillating valve body 66 shown by a solid line in FIG. The upper working fluid supply / discharge port 81 is opened to the switching valve chamber 53, and the lower working fluid supply / discharge port 82 is communicated with the working fluid discharge port 83 by the switching groove 85. Further, in FIG. In the switching position of the oscillating valve element 66, the lower working fluid supply / discharge port 82 is opened to the switching valve chamber 53, and the upper working fluid supply / discharge port 81 is connected to the switching groove 85.
Thereby, it is communicated with the working fluid outlet 83.

Then, as shown in FIG. 2, one of the working fluid supply / discharge holes 71, 72 is connected to the working fluid supply / discharge port 8 of the fixed valve plate 62.
1 and 82, through a switching groove 85 of a swing valve body 66, a working fluid discharge port 83 of a fixed valve plate 62, and a working fluid discharge hole 73, to a muffler installation section 86 provided in the switching mechanism main body 51. Communicated. The muffler installation section 86 is provided with a muffler (not shown) for reducing noise generated when exhausting compressed air as a working fluid.

As shown in FIG. 6, around the shaft hole of the swing valve body 66 which is fitted to the rotation support shaft 61, for example, 180
An engaging portion 87 is provided over the range of °, and around a shaft hole that fits with the rotation support shaft 61 in the switching operation body 68,
For example, the engaging portion 88 is provided over a range of 154 °,
A backlash 89 of, for example, 13 ° is provided between the engagement portions 87 and 88.

Due to these backlashes 89, the gently swinging movement of the first half of the switching operation body 68 is not transmitted to the swing valve body 66, and only the spring operation of the second half of the switching operation body 68 is transmitted to the swing valve body 66. Is done.

Next, as shown in FIGS. 2 and 3,
A spring mounting cylinder 91 is screwed into the switching mechanism main body 51, and a compression coil-shaped spring 92 is fitted inside the spring mounting cylinder 91. A cylindrical slider 93 slidable inside 91 is fitted, and one end rotating shaft portion 96 of an operator 95 is rotatably fitted into an end surface concave portion 94 of the slider 93. An end rotation shaft 97 is rotatably fitted in the recess 98 of the switching operation body 68. An air vent hole 99 is provided in the end surface concave portion 94 of the slider 93.

The spring 92 is compressed and accumulates force until the switching operation body 68 which swings in conjunction with the reciprocating operation of the operation rod 54 reaches the dead point at the neutral position, and the switching operation body 68 is moved to the neutral position. When the dead point is exceeded, the accumulated pressure is released, the switching operation body 68 is instantaneously turned to the opposite side, and the switching operation body 68 is engaged with the switching operation body 68 via the engaging portions 87 and 88. The swing valve element 66 is switched instantaneously.

At this time, since the backlash 89 is provided between the engaging portion 87 of the swing valve body 66 and the engaging portion 88 of the switching operation member 68, the switching operation member 68 is not moved until it reaches a dead point. During the pressure accumulation operation, the swing valve body 66 is stationary, and when the switching operation body 68 exceeding the dead point operates instantaneously due to the accumulated pressure of the spring 92, the engagement portion 88 of the switching operation body 68 Since the engagement portion 87 of the swing valve body 66 is engaged and the swing valve body 66 also switches instantaneously, it is possible to prevent the trouble that the swing valve body 66 stops at the neutral position.

In such a configuration, at least the fixed valve plate 62, the swing valve body 66, and the switching operating body 68 are formed by using a mold using one of a sintered metal and a synthetic resin, thereby facilitating manufacture. Can be achieved. In particular, when these are injection-molded with a synthetic resin, the manufacturing process can be greatly simplified, and a very inexpensive part can be provided. In addition, since the oscillating valve body 66 that slides on the fixed valve plate 62 is structurally less worn as described later, sufficient durability can be obtained even when these are easily manufactured synthetic resin parts. Further, the one molded from the sintered metal is more durable, and can maintain accuracy even when frequently used.

Next, the operation of the embodiment shown in FIGS. 1 to 6 will be described.

When the swing valve body 66 is at the switching position shown in FIG. 1, the working fluid such as compressed air supplied into the switching valve chamber 53 from the working fluid supply hole 52 is supplied to the working fluid supply / discharge port 82. Is supplied to the working fluid chamber 45 through the working fluid supply / discharge hole 72, and at the same time, the working fluid in the opposite working fluid chamber 44 is supplied to the working fluid supply / discharge hole 71, the working fluid supply / discharge port 81, the swing valve body 66. Are discharged to the outside through the switching groove 85, the working fluid discharge port 83 and the working fluid discharge hole 73, so that the working fluid chamber 45 expands and the working fluid chamber 44 contracts, so that the diaphragms 32, 33 on both sides are contracted. And the operating rod 54 moves to the opposite side.

As a result, the pump chamber 35 contracts, and the pumped material in the pump chamber 35 is discharged through the discharge side check valve 42 to the discharge port.
43, the pump chamber 34 expands, and the suction port 38
Then, the pumping material is sucked into the pump chamber 34 through the suction side check valve 36.

At this time, in conjunction with the axial movement of the operating rod 54, the switching operating body 68 that engages with the small-diameter groove 69 of the operating rod 54 via the engaging projection 70 swings to the neutral position, As a result, the slider 93 is connected to the spring-mounted cylinder via the actuator 95.
The spring 92 is pushed into the spring 91, and the spring 92 is compressed and accumulated.

Further, when the switching operation body 68 exceeds a dead point at a neutral position perpendicular to the operation rod 54, the force accumulated in the spring 92 at that time is released, and the switching operation body 68 is momentarily moved to the opposite side. The swinging valve body 66 engaged with the switching operation body 68 and the engagement portions 87 and 88 also instantaneously switches to the position shown by the solid line in FIG.

Thus, the working fluid such as compressed air supplied from the working fluid supply hole 52 into the switching valve chamber 53 is supplied from the working fluid supply / discharge port 81 to the working fluid chamber 44 via the working fluid supply / discharge hole 71. At the same time, the working fluid in the working fluid chamber 45 on the opposite side is filled with the working fluid supply / discharge hole 72, the working fluid supply / discharge port 82, and the swing valve body 66.
Switching groove 85, working fluid outlet 83 and working fluid outlet 73
Therefore, the working fluid chamber 44 is switched so that the working fluid chamber 44 expands and the working fluid chamber 45 contracts.

The supply and discharge of the working fluid are automatically switched by such a mechanism, and the diaphragms 32 and 33 and the working rod 54 on both sides repeatedly reciprocate. By alternately repeating the suction or discharge of the pumping material by the one diaphragm 32 and the discharge or suction of the pumping material by the other diaphragm 33, the efficiency of the pump action can be increased.

The above-described working fluid supply / discharge switching mechanism 50
Since the swing valve body 66 swinging about the rotation support shaft 61 as a fulcrum swings in parallel with the fixed valve plate 62 provided at right angles to the rotation support shaft 61, The abrasion of the oscillating valve element 66 that moves is structurally reduced.
Is applied to the fixed valve plate 62 in the axial direction of the rotating support shaft 61, and the entire surface of the swinging valve body 66 is pressed uniformly against the fixed valve plate 62. Performance can be improved. Further, when the switching operation body 68 that swings in conjunction with the reciprocating operation of the operation rod 54 exceeds the neutral position, the spring 92
Is released, and the swing valve body 66 engaged with the switching operating body 68 is instantaneously switched, whereby the swing valve body 66 is released.
However, it is possible to prevent a trouble that the exercise stops at the neutral position.

It should be noted that the diaphragm pump using the diaphragms 32 and 33 is more suitable for pumping a pumping material such as chemicals, paints, inks, adhesives, oils, waste oils, filths and sludges than a piston pump using a piston. Suitable.

[0041]

According to the first aspect of the present invention, the swing valve body in the supply / discharge switching mechanism repeats a stable swinging motion about the rotation support shaft, so that the wear of the swing valve body is reduced. Thus, the durability of the supply / discharge switching mechanism can be improved.

According to the second aspect of the present invention, when the oscillating valve body of the working fluid supply / discharge switching mechanism is oscillated about the pivot shaft, the pivot valve is provided at right angles to the pivot shaft. Since the swing valve body swings in parallel with the fixed valve plate, the wear of the swing valve body sliding with the fixed valve plate is structurally reduced, and in particular, partial uneven wear is eliminated, and durability can be improved. . Furthermore, when the switching operating body that swings in conjunction with the reciprocating operation of the operating rod exceeds the neutral position, the force accumulated in the spring is released, and the swinging valve body engaged with the switching operating body is instantaneously released. By performing the switching operation, it is possible to prevent the trouble that the swing valve body stops moving at the neutral position.

According to the third aspect of the present invention, since the variable volume member is made of a diaphragm, chemical products, paints, inks, adhesives, oils, waste oils, filth, sludge, etc. can be used as compared with the case of using a variable volume member of a piston. A pump device suitable for the pressure feeding of the oil.

According to the fourth aspect of the present invention, the suction and discharge of the pumping material by one diaphragm and the suction and discharge of the pumping material by the other diaphragm are alternately repeated, so that the efficiency of the pump action can be improved. .

According to the fifth aspect of the present invention, at least the fixed valve plate, the swing valve body, and the switching operating body can be easily manufactured by molding them with a mold.

According to the sixth aspect of the present invention, at least the fixed valve plate, the swing valve body, and the switching operation body are formed of one of the sintered metal and the synthetic resin. Since the wear of the valve body can be structurally suppressed, these parts can be ensured to have sufficient durability even as synthetic resin parts that are easy to manufacture, and those molded from sintered metal are more durable. Accuracy can be maintained even when the frequency is high.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a pump device according to the present invention.

FIG. 2 is a sectional view showing one embodiment of a supply / discharge switching mechanism of the pump device.

FIG. 3 is a sectional view taken along line III-III of FIG. 2;

FIG. 4 is a plan view showing a switching mechanism main body in a state where an internal mechanism of a switching valve chamber is removed.

FIG. 5 is a partially cutaway plan view showing a relationship between a fixed valve plate and a swing valve body of the supply / discharge switching mechanism.

FIG. 6 is a cross-sectional view showing an engagement portion of a swing valve body and a switching operation body of the supply / discharge switching mechanism.

FIG. 7 is a sectional view showing a conventional pump device.

[Explanation of symbols]

 31 Pump body 32, 33 Diaphragm 34, 35 as volume variable member Pump chamber 44, 45 Working fluid chamber 50 Supply / discharge switching mechanism 51 Switching mechanism body 53 Switching valve chamber 54 Operating rod 61 Rotating support shaft 62 Fixed valve plate 66 Swing valve 68 Switching actuator 81, 82 Working fluid supply / discharge port 83 Working fluid discharge port 92 Spring

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3H075 AA02 AA07 AA08 AA09 AA20 BB04 BB14 BB17 CC08 CC18 CC25 CC32 DA05 DA09 DB10 DB44 3H077 AA03 AA05 AA06 AA08 AA20 BB03 CC02 CC07 CC16 DD09 DD14 EE02 EE12 FF23 FF23 FF23

Claims (6)

[Claims] 1. A pump body, a variable volume member provided in the pump body, a pump chamber formed in the pump body by the variable volume member, and a working fluid partitioned from the pump chamber by the variable volume member. A pump device comprising: a chamber; and a supply / discharge switching mechanism that switches supply / discharge of working fluid to / from the working fluid chamber by a swing valve body that swings around a rotation support shaft. 2. A switching mechanism for supplying and discharging working fluid, comprising: a switching mechanism main body; a switching valve chamber provided inside the switching mechanism main body for receiving pressurized supply of the working fluid; and a variable volume inserted into the switching valve chamber. An operating rod that reciprocates integrally with the member, a rotation support shaft provided in a direction crossing the operation rod, and an operation that is provided at right angles to the rotation support shaft and communicates the switching valve chamber with the working fluid chamber. A fixed valve plate having a fluid supply / discharge port and a working fluid discharge port for discharging the working fluid returned from the working fluid chamber to the outside; and a fixed valve plate swinging around a pivot in the switching valve chamber. An oscillating valve body that slides to switch between supply of working fluid from the switching valve chamber to the working fluid chamber and discharge of working fluid from the working fluid chamber to the outside; and an operation between the operating rod and the oscillating valve body. Swinging in the middle of swinging about the pivot about the fulcrum in conjunction with the reciprocating movement of the rod The switching operation body that engages with the valve body to perform the switching operation of the swing valve body and the switching operation body that swings in conjunction with the reciprocating operation of the operating rod releases the force accumulated when the switching operation body exceeds the neutral position. 2. The pump device according to claim 1, further comprising: a spring that instantaneously switches the swing valve body engaged with the switching operation body. 3. The pump device according to claim 1, wherein the volume variable member is a diaphragm. 4. A pair of diaphragms are provided, an operating rod connects between the pair of diaphragms, and a supply / discharge switching mechanism is provided between a pair of working fluid chambers defined by the pair of diaphragms. The pump device according to claim 3, wherein the pump device is disposed. 5. The pump device according to claim 2, wherein at least the fixed valve plate, the swing valve body, and the switching operation body are formed by a mold. 6. The pump device according to claim 5, wherein at least the fixed valve plate, the swing valve body, and the switching operation body are formed of one of a sintered metal and a synthetic resin.