JPH1028962A - Chemical injection device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To perform stable chemical injection by eliminating clogging and gas lock of a turbine of a chemical injection device powered by a water turbine. SOLUTION: A tube pump 9 injects a drug into a negative pressure portion of an ejector 2 through which a fluid to be injected flows. The power of the turbine 4 rotating by the flow of the injection fluid is transmitted to the tube pump 9. [Effect] Since the power source of the chemical injection is mainly the suction force of the ejector, the pushing power of the tube pump is small. Since there is no need to extract a large amount of power from the water flow turbine, the distance between the turbine blade and the inner wall of the casing can be increased, and flow passage blockage at this portion is prevented. A tube having low pressure resistance is sufficient. The tube pump does not hinder the delivery of chemicals even if air bubbles are mixed in,
It does not cause a gas lock.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drug injection device, and more particularly to a drug injection device that does not use a motor, an engine, or the like.

[0002]

2. Description of the Related Art A conventional general chemical injection device has a drawback that it cannot be used in a place where there is no power source because it is operated by a motor (electric power) or an engine.

[0003] A chemical injection device utilizing the power of a water flow turbine without using these power sources is also provided. However, in this chemical injection device, it is necessary to take out relatively large power from the water flow turbine. The clearance between the turbine blade (turbine blade) and the inner wall of the turbine casing is designed to be small. In addition, since the rotating power of the water flow turbine has a small torque (force) and a large number of rotations, a combination of gears is used to reduce the number of rotations to obtain a large torque. The pump is running.

[0004]

The above-described conventional chemical injection device powered by a water turbine has the following disadvantages. Since the clearance between the turbine blade and the inner wall of the turbine casing is reduced in order to extract a large power from the water turbine, clogging of the turbine due to dust or turbidity in the fluid is likely to occur. Since the chemical injection pump has a check valve, gas lock easily occurs due to air bubbles.

It is possible to prevent gas lock by using a tube pump instead of a pump with a check valve. However, in a conventional drug injection device without an ejector, a tube pump with a small pushing pressure is used. It is difficult to do. In order to increase the pushing pressure of the tube pump, it is necessary to considerably increase the pressure resistance of the tube. However, it is very difficult in practice to constitute a tube pump with such a high pressure resistant tube.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and is a drug injection device which does not require a power source such as a motor and an engine. The drug can perform stable drug injection without causing clogging or gas lock. It is intended to provide a note device.

[0007]

According to the present invention, there is provided a dispensing apparatus comprising: an ejector through which a fluid to be injected flows, power generating means for generating a rotational force by the flow of the fluid to be injected, and a negative pressure of the ejector. It is characterized by comprising a pump for injecting medicine into the generator, and power transmission means for transmitting the rotational force from the power generation means to the pump.

[0008] In the chemical dosing device of the present invention, the power source of the chemical dosing is:
Since it is mainly the suction force of the ejector, the pushing pressure of the pump is small. For this reason, since it is not necessary to take out large power from the power generating means serving as the power source of the pump, it is possible to increase the clearance between the turbine blade and the inner wall of the turbine casing even when a water turbine is used. Therefore, clogging of the turbine is prevented.

As this pump, a positive displacement pump such as a tube pump is preferable. The tube pump does not hinder the delivery of chemicals even if air bubbles are mixed, and does not cause gas lock. In general, a tube pump has a low pushing pressure. However, in the chemical dosing device of the present invention, a tube pump injects a negative pressure into a negative pressure generating section formed by an ejector, and the tube pump has a function of dispensing a fixed amount of medicine. For this reason, the pushing pressure by the tube pump may be low, so that the tube need only have a low pressure resistance.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a chemical injection device according to an embodiment of the present invention.

FIG. 1 is a sectional view of a chemical injection device 1 according to an embodiment.

Reference numeral 2 denotes an ejector, in which a nozzle 3, a turbine 4, and a throat portion 5 are provided from the upstream side, and a turbine casing 6 surrounding the turbine 4 is provided integrally with the ejector 2.

A turbine blade (turbine blade) 7 is provided on the outer periphery of the turbine 4. The rotating shaft of the turbine 4 extends outside the turbine casing 6 through the water seal bearing portion, and a pulley 8 is fixed to the rotating shaft outside the turbine casing 6.

An endless belt 11 is stretched between the pulley 8 and a pulley 10 of a tube pump (roller pump) 9.

The pulley 10 is fixed to a rotating shaft of a rotor 12 of the tube pump 9. The rotor 12 is disposed inside the pump casing 13, and the rotation shaft of the rotor 12 extends outside the pump casing 13 via a water-sealed bearing. The pulley 10 is fixed to the rotating shaft outside the pump casing 13.

A plurality of rotors 14 are rotatably held on the outer periphery of the rotor 12.
A soft tube 15 is arranged between the pump casing 13 and the inner peripheral surface. The rotor 14 is connected to the tube 1
5 is pressed to roll on the tube 15, and the chemical solution in the chemical solution tank 16 is quantitatively sent to the chemical injection port 17.

In this chemical injection device 1, when water is introduced into the ejector 2, the turbine 4 rotates, and this water is ejected from the nozzle 3, so that the water is injected into the chemical injection port 17 around the nozzle 3. Negative pressure is generated.

The rotational power of the turbine 4 is controlled by pulleys 8, 10
And the rotor 12 of the tube pump 9 via the belt 11
And the rotor 12 rotates. With the rotation of the rotor 12, the liquid medicine is sent from the liquid medicine tank 16 to the medicine inlet 17 via the tube 15.

In the chemical injection device 1, since the tube pump 9 for chemical injection is driven by the water flow turbine as described above, chemical injection can be performed without using a motor or an engine.

Further, since the liquid discharged from the tube pump 9 is sucked from the chemical injection port 17 by the negative pressure generated by the ejector 2, the discharge pressure (push-in pressure) of the tube pump 9 is extremely low. Therefore, the output torque of the turbine 4 can be reduced, so that the clearance between the turbine blade 7 and the inner peripheral surface of the turbine casing 6 can be increased, and clogging of the turbine can be prevented. In addition, since the discharge pressure of the tube pump 9 can be low, the tube 15 need only have a low pressure resistance. Further, since the chemical solution is sucked by the negative pressure of the ejector 2 as described above, priming is not required at the time of startup, and the startup is easy. Also, should the pipes such as the tube 15 come off or crack, only the atmosphere is sucked into the chemical injection system, and no water leaks from the ejector 2.

Since the tube pump 9 does not hinder the liquid sending even if bubbles are mixed in, the liquid can be sent stably.

In the illustrated chemical injection device, a power transmission mechanism using a pulley and a belt is adopted as a power transmission means from the turbine 4, but a chain mechanism, a gear mechanism,
Various power transmission mechanisms such as a crank mechanism may be employed. Further, a plurality of power transmission mechanisms may be combined. For example, in the illustrated injection device, the pulley 10 is connected to the rotor 12.
Gears may be interposed between them without directly connecting them.

This power transmission mechanism may include various speed increasing mechanisms and various speed reducing mechanisms.

In addition, various displacement pumps such as a screw pump can be used in place of the tube pump 9. It should be noted that a pump with a check valve in which the valve does not work due to suction is inappropriate.

[0025] In such a chemical infusion device of the present invention,
Examples of the liquid to be injected include water, other liquids and gases. The chemical may be a gas or a liquid.

[0026]

As described above in detail, according to the chemical dosing device of the present invention, stable chemical dosing can be performed without requiring a power source such as a motor or an engine and without causing clogging and gas lock. .

[Brief description of the drawings]

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chemical injection device 2 Ejector 3 Nozzle 4 Turbine 5 Throat part 6 Turbine casing 7 Turbine blade 8,10 Pulley 9 Tube pump 11 Belt 12 Rotor 13 Pump casing 14 Rotor 15 Tube 16 Chemical liquid tank 17 Chemical injection port

Claims (2)

[Claims] 1. An ejector through which a fluid to be injected flows, power generating means for generating a rotational force by the flow of the fluid to be injected, a pump for injecting a negative pressure into the ejector, A power transmitting means for transmitting the rotational force from the generating means to the pump. 2. The chemical dispensing device according to claim 1, wherein the pump is a positive displacement pump.