JPS6240558B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a diaphragm pump.

[Technical background of the invention and its problems]

For example, diaphragm pumps are suitable for pumps used in process control because they do not destroy the molecules of the pumped fluid, but conventional diaphragm pumps have two The left and right push pins are alternately pressed by the clamp plate of the diaphragm, and the contacts at the left and right ends of the valve member of the pilot valve device are alternately pressed by the retaining nuts screwed into the external threads of the left and right push pins. It was designed to press, and then
In order to adjust the effective length of the pump stroke, the switching timing of the pump can be adjusted by rotating the left and right locking nuts, respectively, and adjusting the movement on the external thread of the pin.

As described above, although the conventional diaphragm pump has a switching timing adjustment mechanism (locking nut), the locking nut must be adjusted manually and cannot be controlled automatically or remotely. Furthermore, while the pump is operating, the push pin is also moved forward and backward, so the rotation of the locking nut screwed onto this pin cannot be adjusted, and the pilot valve device cannot be switched manually while the pump is operating. I can't adjust the timing. For this reason, the conventional diaphragm pump described above is not suitable for process control applications. In addition, in conventional diaphragm pumps, the left and right locking nuts are adjusted separately, so care must be taken to ensure that the amount of movement adjustment of the left side locking nut is always equal to the amount of movement adjustment of the right side locking nut. However, this is not easy, and if the left and right adjustment amounts are different, there is a problem that the discharge amount from the left and right pump chambers will be unbalanced.

[Purpose of the invention]

The present invention aims to provide a diaphragm pump that can automatically change the amount of left and right movement of the diaphragm in a well-balanced manner even during pump operation, and is suitable as a pump used in process control. It is.

[Summary of the invention]

In the diaphragm pump of the present invention, left and right diaphragms are provided on the left and right sides of the pump body to form a working fluid chamber and a pump chamber, respectively. By supplying and discharging working fluid, the left and right diaphragms move forward and backward into the pump chamber, and the pressurized fluid sucked into the pump chamber from the pump suction port via the suction check valve is pumped via the discharge check valve. A diaphragm pump that discharges from a discharge port includes an electromagnetic switching valve that alternately controls the supply and discharge of working fluid to and from the left and right working fluid chambers, and a solenoid switching valve that operates in conjunction with the reciprocating motion of the diaphragm. It is equipped with a switch that issues a switching signal, and a variable operation timing mechanism that changes the operation timing of this switch. , and a pair of left and right switch opening/closing parts whose mutual spacing can be equally expanded and contracted by rotation of the pair of left and right reverse threaded threaded parts, and its operation is performed by connecting the rotational drive system to a stepping motor or the like. By driving the left and right switch opening/closing parts, the left and right pair of counter-screw threaded parts are rotated simultaneously, and the left and right switch opening/closing parts are adjusted to expand and contract equally, and the solenoid valve switching timing by the left and right switch opening/closing parts is automatically adjusted. The amount of discharge per reciprocation from the left and right pump chambers is adjusted to increase or decrease equally from the left and right pump chambers.

[Embodiments of the invention]

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

FIG. 1 shows a first embodiment of the present invention, in which left and right diaphragms 4 are provided on the left and right sides of a pump body 1 to form a working fluid chamber 2 and a pump chamber 3, respectively. By connecting air as a working fluid to and from the left and right working fluid chambers 2 alternately, the left and right diaphragms 4 are moved forward and backward into the pump chamber 3, and the air is pumped from the pump suction port 6. The pumped liquid as pumped fluid sucked into the pump chamber 3 via the suction check valve 7 is discharged from the pump discharge port 9 via the discharge check valve 8.

Such a diaphragm pump is provided with an electromagnetic switching valve 11 that alternately controls supply and discharge of air to and from the left and right working fluid chambers 2, and operates in conjunction with the reciprocation of the diaphragm 4 to control the electromagnetic switching valve 1.
A reed switch 12 is provided on the inner wall surface of the working fluid chamber 2, and the reed switch 12 is installed on the inner wall of the working fluid chamber 2, and the reed switch 12 is placed on the upper part of the disk 13 that clamps the center portions of the left and right diaphragms 4.
Magnet 14 as a switch opening/closing part for turning off
The rod 5 is provided with an operation timing variable mechanism 15 for fixing the switch 12 and changing the operation timing of the switch 12.

That is, the rod 5 has left and right threaded rods 5b screwed into the left and right threaded holes 16 of the center rod 5a with left and right reverse threads, and a part of the worm wheel 18 is slid into the axial groove 17 of the center rod 5a. The worm wheel 18 is rotatably fitted into the central boss portion 19 of the pump body 1 and integrated with a cylindrical portion 21 which is locked by a ring 20 so as not to move in the axial direction. The rotating shaft of a worm 22 that meshes with the worm wheel 18 is rotatably received by the pump body 1. The rotation shaft of the worm 22 is rotated manually or automatically by a stepping motor or the like outside the pump body 1. This motor, worm 22, and worm wheel 18 constitute a rotational drive system of the variable operation timing mechanism 15.

Then, in the state shown in FIG. 1, the right reed switch 12 is turned on by the magnet 14, and when the electromagnetic switching valve 11 is switched to a side different from the state shown in the figure through an amplifier etc., the air pressure source is turned on. 25 is supplied to the working fluid chamber 2 on the right side, and the diaphragm 4 expands to the right side and discharges the liquid in the pump chamber 3 on the right side through the check valve 8. At the same time, the pump chamber 3 on the left side expands. The liquid is sucked through the check valve 7. When the left magnet 14 approaches the left reed switch 12, this reed switch 12 is activated and the electromagnetic switching valve 1
1 is switched to the state shown in FIG. 1, and the left and right pump chambers 3 perform an action opposite to the above action.

In this way, the electromagnetic switching valve 11 is automatically switched in response to a command from the left and right reed switches 12, and the left and right diaphragms 4 are moved left and right by a predetermined count amount to force-feed a fixed amount of liquid in total. can.

When variably adjusting this amount, when the worm wheel 18 is rotated by the worm 22 rotated by a stepping motor or the like, the worm wheel 18 is rotated in the center relative to the threaded rod 5b, which is integral with the diaphragm 4 and cannot be rotated. Since the rod 5a rotates,
The left and right threaded rods 5b, which are threaded onto the center rod 5a with left and right reverse threads, approach or separate equally from each other. As a result, when the left and right magnets 14 approach the left and right reed switches 12 equally, the diaphragm 4
The operating amount of the diaphragm 4 decreases, and even if the number of repetitions of the reciprocating motion is constant, the discharge amount of the pumped liquid decreases.Conversely, when the left and right magnets 14 are equally spaced from the left and right reed switches 12, the operating amount of the diaphragm 4 increases. , the discharge amount of the pumped liquid increases.

Next, FIG. 2 shows a second embodiment of the present invention, in which a contact plate 32 of a switch 31 operates in conjunction with the reciprocating motion of the diaphragm 4 to issue a switching signal for operating the electromagnetic switching valve 11. is provided integrally with the rod 5, and also includes an operation timing variable mechanism 33 that changes the operation timing of this switch 31.
is provided around the contact plate 32.

That is, the worm 3 is placed in the center of the pump body 1.
A small-diameter gear 36 is provided rotatably between the pump body 1 and a small-diameter gear 36 is provided integrally on the left and right through a worm wheel 35 that meshes with the worm 34. The boss portions 38 of the left and right large-diameter gears 37 that mesh with each other are connected to the pump body 1.
Screw it into the recess 39 with left and right reverse threads. Reference numeral 40 indicates the screwing part. The left and right large-diameter gears 37 are loosely fitted into the rod 5, and the left and right opposing surfaces thereof serve as stationary contacts as switch opening/closing portions that face reciprocating contacts 41 provided on the left and right surfaces of the contact plate 32. 42 are integrally protruded.

Then, when the electric contacts 41 and 42 on the left side come into contact in the state shown in FIG. The left and right diaphragms 4 and rods 5 move to the right to perform a pumping action. and rod 5
When the contact plate 32 integrated with the large-diameter gear 37 on the right approaches the large-diameter gear 37 on the right and the contacts 41 and 42 on the right come into contact, the electromagnetic switching valve 11 is switched to the state shown in FIG. 2, and the pump action is performed in the opposite direction. conduct. The pump action is repeatedly performed by such automatic switching, and the stroke of the rod 5 at that time is a distance that allows the contact plate 32 to move between the left and right large-diameter gears 37.

When the stroke of this rod 5 is variably adjusted, that is, when the pump discharge amount is variably adjusted, the worm 34 is rotated by a stepping motor or the like, and the large diameter When the gears 37 are rotated in the same direction, the left and right large-diameter gears 37 equally approach or separate from each other due to the threaded portions 40 having opposite left and right threads. When the left and right large-diameter gears 37 approach, the discharge amount of the pumped liquid decreases, and when they move apart, it increases. The motor, worm 34, worm wheel 35, etc. constitute a rotational drive system for the variable operation timing mechanism 33.

Further, as a modification of the second embodiment shown in FIG. 2, a limit switch or the like is provided on each of the left and right large-diameter gears 37, and an operating plate for operating the limit switch or the like is integrated into the rod 5 instead of the contact plate 32. The electromagnetic switching valve 11 may be controlled by the left and right limit switches or the like.

Furthermore, in the first and second embodiments described above, the check valves 7 and 8 are simple ball valves, but instead of the ball valves, as shown in FIG. 3, a fluid pressure operated check valve 51, It may be set to 52. That is, a piston 54 is provided on the valve rod 53 of the check valves 51 and 52,
This piston 54 is fitted into a cylinder 55, and both ends of this cylinder 55 are provided with fluid pressure, for example, pneumatic pressure supply/discharge ports 56.

Then, before switching the left and right diaphragms 4, the check valves 51 and 52 are forcibly opened and closed by the fluid pressure actuator consisting of the cylinder 55 and the piston 54. If the diaphragm 4 is operated to switch after sensing the opening/closing of the diaphragm 52 and confirming the opening/closing, quantitative performance becomes more reliable.

〔Effect of the invention〕

According to the present invention, an electromagnetic switching valve alternately controls supply and discharge of working fluid to left and right working fluid chambers, and a switching signal for operating the electromagnetic switching valve in conjunction with the reciprocation of the diaphragm. The variable operation timing mechanism includes a switch and a variable operation timing mechanism that changes the operation timing of the switch. Since the pump has a pair of left and right switch opening/closing parts whose mutual spacing can be equally expanded and contracted by rotation of the reverse threaded threaded part, this pump can be operated by driving the rotational drive system with a stepping motor or the like. Even during operation, the variable operation timing mechanism can be automatically controlled remotely, making it compatible with process control using a computer. In addition, the variable operation timing mechanism of the present invention allows the pair of left and right switch opening/closing parts to be adjusted to expand and contract equally by simultaneously rotating the left and right pair of counter-screw threaded parts using one rotary drive system. By adjusting the left and right switch opening/closing parts in a well-balanced manner, the discharge amount per reciprocation from the left and right pump chambers can be adjusted to increase or decrease equally on both sides.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a first embodiment of the diaphragm pump of the present invention, FIG. 2 is a sectional view showing the second embodiment, and FIG. 3 is a sectional view showing a modification of the check valve. . 1...Pump body, 2...Working fluid chamber, 3...
Pump chamber, 4...diaphragm, 5...rod,
6... Pump suction port, 7... Suction check valve, 8...
...Discharge check valve, 9...Pump discharge port, 11...
Solenoid switching valve, 12, 31...Switch, 14, 4
2... Switch opening/closing part, 15, 33... Operation timing variable mechanism, 18, 22 or 34, 35...
...Rotary drive system.

Claims (1)

[Scope of Claims] 1 Left and right diaphragms are provided on the left and right sides of the pump body to form a working fluid chamber and a pump chamber, respectively, and the left and right diaphragms are connected by a rod, so that the left and right working fluid chambers are alternately connected. By supplying and discharging working fluid, the left and right diaphragms move forward and backward into the pump chamber, and the pressurized fluid sucked into the pump chamber from the pump suction port via the suction check valve is pumped via the discharge check valve. In a diaphragm pump that discharges from a discharge port, an electromagnetic switching valve that alternately controls supply and discharge of working fluid to the left and right working fluid chambers;
It is equipped with a switch that operates in conjunction with the reciprocating movement of the diaphragm to issue a switching signal for operating the electromagnetic switching valve, and a variable operation timing mechanism that changes the operation timing of this switch. a pair of left and right reverse screw threaded parts that are simultaneously rotated by two rotational drive systems;
A diaphragm pump characterized in that it has a pair of left and right switch opening/closing parts whose mutual spacing can be equally expanded and contracted by rotation of the pair of left and right reverse screw threaded parts. 2 The variable operation timing mechanism is a mechanism that variably adjusts the positional relationship of the switch opening/closing part, which is provided integrally with the diaphragm and opens and closes the switch, with respect to the switch provided on the pump body by expanding and contracting the rod between the left and right diaphragms. A diaphragm pump according to claim 1, characterized in that: 3. The variable operation timing mechanism is characterized in that stationary contacts, which serve as switch opening/closing parts for opening and closing the switch, are movably provided on both sides of a reciprocating contact provided integrally with the rod. The diaphragm pump according to item 1. 4. According to any one of claims 1 to 3, the suction check valve and the discharge check valve are forcibly opened and closed before switching the diaphragm. Diaphragm pump as described.