JP4860171B2 - Metering pump - Google Patents

Description

  The present invention relates to a metering pump, and more particularly, to a metering pump that does not have a mechanical sliding portion in order to suitably fill a container with a highly flammable organic solvent such as alcohol or acetone.

  Conventionally, a metering pump capable of accurately delivering a certain amount of liquid has been provided. As the metering pump, various types of pumps such as a reciprocating type and a diaphragm type are used depending on the type and properties of the target liquid.

  A reciprocating pump represented by a piston type or the like has a structure in which a piston reciprocates in a cylinder, and has a so-called sliding portion and is provided with a seal member such as an O-ring.

  The diaphragm type has a structure in which a part of the pump chamber is formed of a diaphragm, and this diaphragm is expanded and contracted by a motor, hydraulic pressure, air pressure or the like to increase or decrease the volume of the pump chamber. The pump chamber is provided with a suction port for sucking fluid and a discharge port for discharging.

  In addition, a pump combining these has been developed. For example, the metering pumps disclosed in Japanese Patent Application Laid-Open Nos. 2001-182660 and 2001-193653 are metering pumps that suck and discharge the discharged fluid into the pressure chamber by the reciprocating motion of the piston unit. A first piston member and a second piston member are coupled via a retainer member, and a discharge diaphragm and a pressure diaphragm are arranged opposite to each other on the retainer member side of the first piston member and the second piston member, and are mutually connected. The folded portion of the diaphragm is arranged so as to face outward.

  However, if there is a mechanical sliding part inside the pump, it is usually necessary to apply a lubricant such as grease to the part to reduce friction and ensure smooth movement. When the liquid to be handled is an organic solvent such as alcohol or acetone, such a lubricant is dissolved by the organic solvent and becomes useless. Therefore, a great frictional force acts on the sliding portion, and such a metering pump cannot be used at all.

In the case of a pump that can be moved by a motor, electricity, etc., if the target liquid is a highly flammable organic solvent such as alcohol or acetone, there is a risk of ignition by sparks or heating. was there.
Therefore, the applicant of the present application has applied for a patent to solve those problems (Japanese Patent Application No. 2003-433941).

JP 2001-182660 A JP 2001-193653 A

In the invention according to the above-mentioned patent application (Japanese Patent Application No. 2003-433941) filed by the applicant, a metering pump with various improvements such as using a diaphragm has been developed and provided from the viewpoint of eliminating the sliding portion of the metering pump. did. As a result, highly flammable organic solvents such as alcohol and acetone, which have been difficult to handle, can be quantified safely and reliably.
However, there has been a demand for the development of a metering pump that is simpler in structure and more inexpensive.

  Therefore, in the present invention, in order to realize such a demand, a metering pump capable of safely and reliably quantifying highly flammable organic solvents such as alcohol and acetone, and has a mechanical sliding portion inside. Therefore, an object of the present invention is to provide a metering pump that is simple in structure and inexpensive.

In order to solve the above-mentioned problem, the invention according to claim 1 is a metering pump that sucks and discharges a predetermined amount of liquid, and an air supply port into which pressurized air is introduced and the supplied pressurized air are discharged. The air supply port and the air discharge port are connected by an air passage tube formed in a diameter smaller than the diameter of the air supply port and the air discharge port ; A decompression chamber that is communicated with the air passage tube of the introduction part through the suction path and decompressed by Bernoulli's theorem by introducing pressurized air into the air introduction part, a suction port for sucking the liquid, and the sucked liquid A cylinder part provided with a discharge port for discharging, a communication pipe connecting the decompression chamber and the cylinder part by a transparent pipe member provided with a scale on the surface, and a float arranged in the decompression room , wherein suction Decrease from mouth And buoyant by the liquid introduced into the chamber and a float for closing a suction path connecting the vacuum chamber and the air introduction part, the valve is provided for opening and closing the flow pipe and the liquid guiding liquid discharged to the discharge port The inside of the cylinder part is decompressed through the decompression chamber and the communication pipe by introducing pressurized air into the air introduction part, thereby sucking the liquid from the suction port into the cylinder part, When the sucked liquid is further introduced into the decompression chamber through the communication pipe, the float floats to block the suction path connecting the air introduction portion and the decompression chamber, whereby a certain amount of liquid is sucked and held, and enters the air from the air outlet side by a larger pressure to stop the supply of pressurized air to open the vacuum chamber from the vacuum state through the suction path, it is stored inside the cylinder While discharging the liquid from the discharge port, characterized in that it is capable metering liquids desired amount by opening and closing a valve in accordance with the scale provided on the communicating pipe.

  In order to solve the above-mentioned problem, the invention according to claim 2 is the metering pump according to claim 1, wherein the float has a substantially spherical shape, and a substantially circular opening provided in the decompression chamber has a curved surface. It is characterized in that the suction path is closed by sealing.

  In order to solve the above-mentioned problems, the invention described in claim 3 is characterized in that in the metering pump according to claim 1 or 2, valve means for controlling the introduction of pressurized air to the air introduction part is provided. To do.

  In order to solve the above problem, the invention according to claim 4 is the metering pump according to claim 3, wherein the valve means discharges the sucked liquid in a pressurized state by introducing pressurized air into the pump. It is characterized by having a mechanism to perform.

  According to the metering pump of the present invention, since it does not have a mechanical sliding portion inside, it can be reliably handled without being hindered by an organic solvent such as alcohol or acetone, and has a simple structure. Therefore, the maintenance is easy, and there is an effect that it can be provided at a low cost.

  In addition, according to the metering pump according to the present invention, since it is moved by pressurized air instead of a motor or electricity, it can be safely performed without causing problems such as ignition to highly flammable organic solvents such as alcohol and acetone. There is an effect that the container can be filled.

  Hereinafter, the metering pump according to the present invention will be described in detail based on the illustrated preferred embodiment. FIG. 1 is a schematic sectional view of an embodiment of a metering pump 1 according to the present invention.

  The illustrated metering pump 1 is in communication with an air introduction unit 10 through which pressurized air is introduced, and the air introduction unit 10 and the suction path 17, and is decompressed by introducing pressurized air into the air introduction unit 10. A decompression chamber 20, a suction port 31 for sucking a liquid and a cylinder portion 30 provided with a discharge port 33 for discharging the sucked liquid, a communication pipe 40 connecting the decompression chamber 20 and the cylinder portion 30, and a decompression chamber 20 and a float 25 disposed in the inside.

  The air introduction unit 10 includes an air supply port 11 through which pressurized air is introduced, and an air discharge port 13 through which the supplied pressurized air is discharged. The air supply port 11 and the air discharge port 13 are air They are connected by a passage tube 15. The air passage tube 15 is formed to have a diameter smaller than the diameters of the air supply port 11 and the air discharge port 13. The air passage pipe 15 is provided with a suction passage 17 connected to the decompression chamber 20. As a result, when pressurized air is introduced from the air supply port 11, the pressurized air passes through the small diameter air passage tube 15 and is discharged from the air discharge port 13 through the suction passage 17. Is in a reduced pressure state.

  On the other hand, a pipe 3a for supplying pressurized air from a pressure pump (not shown) is connected to the air supply port 11, and the pipe 3a is used for supplying and stopping pressurized air. A valve 3b is provided. Further, a pipe 5a for discharging the pressurized air supplied from the air supply port 11 is connected to the air discharge port 13, and a valve 5b is similarly provided in the pipe 5a. .

The decompression chamber 20 is communicated with the air introduction part 10 via the suction path 17, and a float 25 is housed therein.
The float 25 is formed in a substantially spherical shape, and the inside thereof is hollow so as to float by the liquid to be handled. As will be described later, the liquid to be quantified is supplied into the decompression chamber 20, and the float 25 is floated in the decompression chamber 20 by the supplied liquid. It is to do. Here, the float 25 is preferably formed of a material having resistance to an organic solvent to be measured by the metering pump 1. If it has such conditions, it can be formed by, for example, a synthetic resin such as plastic, or a metal material, and the material for forming the float 25 does not ask the kind. The float 25 may be solid as long as the float 25 can float in a liquid, such as wood.

As shown in FIG. 1, a circular opening 21 corresponding to the curvature of the surface of the float 25 is formed on the upper side of the decompression chamber 20 so that the surface of the float 25 is in close contact. In the present embodiment, a packing member 23 is attached around the opening 21 in order to further secure the contact state with the float 25.
On the other hand, an opening end 41 on one side of the communication pipe 40 is connected to the decompression chamber 20, thereby communicating with the cylinder part 30.

  The cylinder part 30 is disposed on the lower side of the decompression chamber 20 and is formed with a space for storing a predetermined amount of liquid. A suction port 31 for sucking a liquid to be quantified is provided at the bottom of the cylinder part 30. A check valve 31a is disposed at the suction port 31 and opens in a direction in which the liquid is sucked into the cylinder part 30, but in the case opposite to the direction, the liquid is not discharged. It has a structure.

  On the other hand, a discharge port 33 for discharging the liquid sucked into the cylinder part 30 to the outside is provided on the left side surface of the cylinder part 30 in FIG. The discharge port 33 is also provided with a check valve (not shown) that opens in the direction of discharging the liquid to the outside of the cylinder part 30 but does not open in the opposite direction. The discharge port 33 is provided with a filling means, that is, a pipe 35a for guiding the discharged liquid, and the pipe 35a is provided with a valve 35b for opening and closing the flow of the discharged liquid. For example, a container 70 filled with a quantified liquid can be connected to the tip of the pipe 35a. In addition, what is necessary is just to determine the magnitude | size of the space in the cylinder part 30 suitably. Further, the other opening end 43 of the communication pipe 40 is connected to the cylinder part 30, so that the cylinder part 30 communicates with the decompression chamber 20.

  The communication pipe 40 is a hollow pipe member that connects the decompression chamber 20 and the cylinder part 30 to each other. For example, the communication pipe 40 can observe the movement state of the liquid to be quantified from the outside by using a transparent pipe material such as glass or acrylic, and if a scale is provided on the surface of the communication pipe 40, the scale is provided. It is also possible to configure so that a desired amount of liquid can be measured.

  Next, operation | movement of the metering pump 1 which concerns on this invention mentioned above is demonstrated. FIG. 2 is a schematic cross-sectional view showing a state in which the tip of the pipe 60 connected to the suction port 31 of the metering pump 1 according to the present invention is immersed in the tank 50 containing the organic solvent 51 before the organic solvent 51 is sucked. It is the figure which showed the step. FIG. 3 is a diagram showing a stage during the suction of the organic solvent 51. FIG. 4 is a diagram showing a stage before the organic solvent 51 is discharged. FIG. 5 is a diagram showing the discharge of the organic solvent.

  First, the tip of the pipe 60 connected to the suction port 31 of the metering pump 1 according to the present invention is immersed in the tank 50 containing the organic solvent 51. Next, a pump (not shown) such as a compressor is connected to the pipe 3a to enable the introduction of pressurized air. Then, the valve 3b and the valve 5b are opened, and introduction of pressurized air into the air supply port 11 is started. When the pressurized air is introduced into the air introduction part 10 from the air supply port 11, the pressurized air continues to be discharged from the air discharge port 13 while passing through the air passage pipe 15 (see FIG. 2). Since the air passage tube 15 has a smaller cross-sectional area of the diameter of the passage than the air supply port 11, a pressure drop phenomenon occurs in the air passage tube 15 due to Bernoulli's theorem. As a result, the inside of the decompression chamber 20 is gradually decompressed through the suction path 17.

  As the inside of the decompression chamber 20 is decompressed, the pressure in the cylinder portion 30 gradually decreases through the communication pipe 40. In conjunction with this, the check valve 31 a of the suction port 31 is opened, and the organic solvent 51 is sucked into the cylinder part 30 through the pipe 60. Then, the organic solvent 51 sucked into the cylinder part 30 flows into the decompression chamber 20 through the communication pipe 40. When the inside of the decompression chamber 20 flows in with the organic solvent 51, the float 25 starts to float gradually by the organic solvent 51 filled in the decompression chamber 20. Finally, it is pressed against the packing member 23. When the float 25 is in close contact with the packing member 23 of the opening 21, the suction path 17 is closed, and as a result, the opening 21 is completely airtight (see FIG. 3).

  When this happens, the valve 3b is closed and the supply of pressurized air is stopped. Then, as shown in FIG. 4, air enters from the air discharge port 13 side by the atmospheric pressure, and the decompression state of the decompression chamber 20 is gradually eliminated through the suction path 17, and gradually returns to the normal pressure state. Therefore, the liquid in the decompression chamber 20 is relatively pressurized, and is pressed toward the cylinder portion 30 through the communication pipe 40. Thereby, the organic solvent 51 in the cylinder part 30 is discharged from the discharge port 33. And if the valve | bulb 35b is opened after attaching the container 70 to the front-end | tip of the piping 35, the organic solvent 51 will be filled in the container 70. FIG. When the container 70 is filled with a predetermined amount of the organic solvent 51, the valve 35b is closed. When the valve 3 b is opened again and pressurized air is introduced from the air supply port 11, the above-described operation is repeated and the organic solvent 51 in the tank 50 is sucked into the cylinder portion 30.

  As described above, an embodiment of the metering pump according to the present invention has been shown. However, in the state where the organic solvent 51 is sucked into the cylinder part 30 and the decompression chamber 20 and the float 25 is in close contact with the opening part 21, If the valve 5b is closed, the metering pump 1 can be held in a state filled with the organic solvent 51.

  On the other hand, as shown in FIG. 5, the pressurized air from the pressurizing pump 80 is arranged to be supplied to the pipe 3a and the pipe 7a connected to the pipe 5a, and the pipe 7a is arranged to communicate with the pipe 5a. Set up. The pipe 3a is provided with a valve 3b, the pipe 5a is provided with a valve 5b, and the pipe 7a is provided with a valve 7b. As a result, it is possible to fill the container 70 with pressurized air together with the organic solvent 51. That is, when supply of pressurized air from the pressure pump 80 is started with the valve 7b closed and the valves 3b and 5b opened, the pressurized air is introduced into the air supply port 11 via the pipe 3a. 15 through the valve 5b opened from the pipe 5a. As a result, the organic solvent 51 is sucked into the cylinder part 30 and the decompression chamber 20. When a predetermined amount of the organic solvent 51 is filled, the valve 3b and the valve 5b are closed and the valve 7b is opened. Then, pressurized air is supplied into the decompression chamber 20 through the air discharge port 13. Accordingly, the pressurized air is filled until the inside of the container 70 becomes the same pressure as the pressurized air.

  As described above, the metering pump according to the present invention does not have a sliding portion, and has a simpler mechanism than conventional metering pumps, so it has good maintainability and can be provided at low cost. However, the above-described embodiment is an example and is not limited thereto. In addition, the metering pump according to the present invention can be used very suitably for an organic solvent, but is not limited thereto, and can of course be used for various liquids.

It is a schematic sectional drawing in one embodiment of a metering pump concerning the present invention. It is a schematic sectional drawing which shows the pre-stage of the state which attracts | sucks an organic solvent with the metering pump shown in FIG. It is a schematic sectional drawing which shows the state which attracted | sucked the organic solvent with the metering pump shown in FIG. It is a schematic sectional drawing which shows the state which discharged the organic solvent attracted | sucked with the metering pump shown in FIG. It is a block diagram which shows one Example of piping and a valve | bulb at the time of introducing pressurized air into an air introduction part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metering pump 3a, 5a, 7a Piping 3b, 5b, 7b Valve 10 Air introduction part 11 Air supply port 13 Air discharge port 15 Air passage pipe 17 Suction path 20 Decompression chamber 21 Opening part 23 Packing member 25 Float 30 Cylinder part 31 Suction Port 31a Check valve 33 Discharge port 35a Pipe 35b Valve 40 Communication pipe 41, 43 Open end 50 Tank 51 Organic solvent 60 Pipe 80 Pressure pump

Claims (4)

In a metering pump that sucks and discharges a predetermined amount of liquid,
An air supply port through which pressurized air is introduced; and an air discharge port through which the supplied pressurized air is discharged. The air supply port and the air discharge port are the diameters of the air supply port and the air discharge port. An air introduction portion formed by being connected by an air passage tube formed in a smaller diameter size ,
A decompression chamber communicated with the air passage tube of the air introduction part via a suction path, and decompressed by Bernoulli's theorem by introducing pressurized air into the air introduction part;
A cylinder part provided with a suction port for sucking liquid and a discharge port for discharging the sucked liquid;
A communication pipe connecting the decompression chamber and the cylinder part by a transparent pipe having a scale on the surface; and
A float disposed in the decompression chamber, wherein the float is floated by the liquid introduced into the decompression chamber from the suction port and closes the suction path connecting the air introduction unit and the decompression chamber;
With
The discharge port is configured with a filling means provided with a pipe for guiding the liquid to be discharged and a valve for opening and closing the flow of the liquid,
By introducing pressurized air into the air introduction part, the inside of the cylinder part is depressurized via the decompression chamber and the communication pipe, whereby liquid is sucked into the cylinder part from the suction port, and the sucked liquid is Further, the float floats by being introduced into the decompression chamber through the communication pipe and blocks the suction path connecting the air introduction part and the decompression chamber, whereby a certain amount of liquid is sucked and held, and enters the air from the air discharge port side by the more the atmospheric pressure to stop the supply of pressurized air, the vacuum chamber through the suction path is opened from the reduced pressure state, the liquid stored within said cylinder While discharging from the discharge port, a desired amount of liquid can be measured by opening and closing the valve according to a scale provided on the communication pipe. Metering pump to be. The metering pump according to claim 1,
The metering pump according to claim 1, wherein the float has a substantially spherical shape, and the suction path is blocked by sealing a substantially circular opening provided in the decompression chamber with a curved surface thereof. The metering pump according to claim 1 or 2,
A metering pump comprising valve means for controlling introduction of pressurized air into the air introduction section. The metering pump according to claim 3,
The metering pump according to claim 1, wherein the valve means includes a mechanism for discharging the sucked liquid in a pressurized state by introducing pressurized air into the pump.

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