JPH09257541A - Liquid fixed quantity supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably supply a small quantity of weighing liquid with simple and inexpensive constitution by arranging a housing part to house a rotary shaft having a weighing part and a liquid flowing passage continuously connected to the weighting part in a body proper, and inserting a vertically freely movable free piston into the weighing part. SOLUTION: An outlet 7a of a soft nylon chemical bag 7 in which chemicals are filled, is inserted into a guide part 2c of a liquid flowing passage 2b bored in an upper surface of a body proper 2. A piston inserting hole 3b is put in a vertical condition, and when a free piston 4 exists in a lower part by dead weight, the chemicals in the chemical bag 7 are injected into a weighing part (a space part) 5. Then, when a rotary shaft 3 rotates by a motor 8, the chemicals in the weighing part 5 rotate in a sealed condition, and the rotary shaft 3 rotates by 180 degrees, and when the piston 4 stops in a condition of coming above, the chemicals in the weighing part 6 are discharged in a test tube 10 housing inspection object water from the guide part 2c of the liquid flowing passage in a lower part of the body proper 2 by dead weight. A similar weighting part 5 is re-formed in an upper part of the piston inserting hole 3b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for quantitatively supplying a small amount of liquid.

[0002]

2. Description of the Related Art Generally, as a device for supplying a very small amount of liquid, there are a tube pump, a diaphragm pump, a piston pump and the like. For example, the structure of the tube pump 21 shown in FIG. Axis 23
And a pair of arms 24 are provided on the rotary shaft 23.
Rollers 25, 2 rotatable at both free ends of the arm 24
5 are provided respectively, and both rollers 25 press the tube 26 disposed in the pump case 22 in an attached state, and the friction between the rollers 26 causes the rollers 25 to rotate. It is designed to pump the liquid of. However, in the tube pump 21, when water or oil adheres to the surface of the tube 26 or each roller 25, the friction between each roller 25 and the tube 26 becomes extremely small, and the tube pump 21 rolls on the tube 26. Each roller 25 slips and each roller 2
5 does not move rotationally, which causes the tube 26 to wear and shorten the life of the tube 26 extremely. Further, the diaphragm pump and the piston pump have many problems such as an increase in dead volume in the pump with respect to the amount of liquid to be delivered and a malfunction due to a defect in an auxiliary device (for example, a check valve). Further, in the case of any of the pumps described above, there is a demand for a liquid constant quantity supply device which is high in cost, good in operability (with few failures) and low in cost.

[0003]

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide a low-cost liquid quantitative supply device capable of stably supplying an extremely small amount of liquid.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems and includes a body body,
A free piston that is movable up and down along with the rotation of the rotating shaft is formed in the measuring unit by forming a liquid flow passage communicating with the measuring unit while forming a storage unit of the rotating shaft provided with the measuring unit. It is characterized by having been inserted.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described. According to the present invention, a body containing a rotary shaft accommodating portion having a measuring portion, and a liquid communicating with the measuring portion. This is realized by forming a flow passage and inserting a free piston that is vertically movable with the rotation of the rotary shaft into the measuring unit. A specific configuration of the liquid constant quantity supply device of the present invention is provided with a body main body, and the body main body is provided with a housing portion for a rotary shaft. The accommodating portion is opened as a hole having a predetermined depth on the side surface of the body body. A liquid flow passage that is orthogonal to the center of the accommodating portion penetrates from the upper surface to the lower surface of the body body. The rotary shaft that fits into the storage portion is provided with a step (smaller than the diameter of the rotary shaft) of a predetermined length from a portion of the rotary shaft that corresponds to the depth of the storage portion, and corresponds to the liquid flow passage. A piston insertion hole that forms a measuring portion is penetrated at a point where the free piston is moved up and down and a free piston having a predetermined length is inserted. A bearing plate having a bearing portion having the same diameter as the stepped portion of the rotary shaft is fixed to the side surface of the body body via the stepped portion. Then, a rotating device having a half-rotation stop function is attached to the end of the step portion of the rotating shaft by an appropriate means. Further, a liquid bag filled in a soft nylon bag to be injected into a liquid flow passage formed in the upper surface of the body is suspended, and a liquid supply unit is arranged in the liquid flow passage on the lower surface.

According to the liquid constant quantity supply device having the above-mentioned structure, when the free piston is in the lower part in the vertical direction by the pist insertion hole formed in the rotary shaft, it is between the piston insertion hole and the length of the free piston. Space part (measurement part)
Then, the liquid in the liquid bag is injected. Then, the rotating device is driven to rotate the rotating shaft by 180 ° and stop. Due to this half-rotation operation, the liquid injected into the space rotates in a sealed state, and the free piston descends due to hydraulic pressure and its own weight, so that the liquid flows through the lower surface of the body body. While dropping from the passage to the liquid supply unit, the next liquid is injected into the space formed in the piston insertion hole. As described above, the liquid constant quantity supply device of the present invention is capable of accurately measuring and feeding a liquid with a simple structure, and can be provided at a low cost, which is very effective.

In the above-described embodiment, the cantilever support system in which a hole of a predetermined depth is formed in the body of the body as the housing for the rotary shaft and the rotary shaft is inserted into this hole is used. A method of supporting both ends of the rotary shaft in which a through hole is formed as a housing portion of the shaft and bearing plates are provided on both side surfaces of the body body can be appropriately selected depending on the implementation.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an explanatory view of the liquid constant quantity supply device of the present invention seen from above, and FIG. 2 is a sectional explanatory view of FIG.

1 and 2, the liquid constant quantity supply device 1 of the present invention includes, for example, a water quality inspection line in which a chemical liquid is added to water to be inspected in a test tube in water quality inspection and the water quality is determined by the reaction. It is used as a device for automatically and quantitatively supplying a chemical solution. The structure of this device is such that a rectangular body 2 is provided, and a circular hole having a predetermined depth is formed as a housing portion 2a of the rotary shaft 3 on one side surface of the body 2.
A liquid flow passage 2b which is orthogonal to the center of the housing portion 2a penetrates from the upper surface to the lower surface of the body 2 and predetermined guide portions 2c are formed on the upper surface and the lower surface. The housing portion 2a
The rotary shaft 3 fitted in the rotary shaft 3 is fitted into the housing portion 2a of the rotary shaft 3.
The step portion 3a (which is smaller than the diameter of the rotating shaft) is provided from a position corresponding to the depth of the liquid flow passage 2
Piston insertion hole 3 that forms a measuring portion at a location corresponding to b
A free piston 4 having a predetermined length is inserted through the piston insertion hole 3b, and a space formed by the piston insertion hole 3b and the free piston 4 serves as a measuring portion 5.
Then, the rotary shaft 3 having the free piston 4 inserted therein is fitted into the accommodating portion 2a, and the rectangular bearing plate 6 in which the bearing portion 6a having the same diameter as the stepped portion 3a of the rotary shaft 3 is bored is attached to the rotary shaft. It is fixed to the side surface of the body 2 through the stepped portion 3a.

The liquid quantitative supply device having the above structure is arranged at a predetermined position of the water quality inspection line, and as shown in FIG. 2, a chemical solution bag 7 in which a chemical solution is filled in a soft nylon bag is suspended and the chemical solution bag 7 is suspended. The outlet 7a is inserted into the guide portion 2c of the liquid flow passage 2b formed on the upper surface of the body body 2. On the other hand, the piston insertion hole 3b formed in the rotary shaft 3 is superposed at a position corresponding to the liquid flow passage 2b, and in this superposed state, at the end of the stepped portion 3a of the rotary shaft 3, for example, a half The motor 8 having a rotation stopping function is connected by an appropriate means. In FIG. 2, reference numeral 9 indicates the liquid flow passage 2
It is an injection port inserted into the outlet side of b, and reference numeral 10 is
This is a test tube containing the water to be inspected.

According to the liquid constant quantity supply device having the above-mentioned configuration, as shown in A of the operation explanatory view of FIG. 3, when the piston insertion hole 3b is in the vertical direction and the free piston 4 is at the lower part by its own weight, the measuring portion 5 is The drug solution in the liquid bag 7 is injected into the. Then, the motor 8 is driven and the rotating shaft 3 stops half-rotated, but as shown in FIG. 3B, when the rotating shaft 3 rotates and turns sideways (90 ° rotation), the weighing unit 5 is rotated. When the chemical liquid of No. 2 is sealed and accumulated, and further rotated 90 ° to the state of C of FIG. 3, the free piston 4 descends as shown by D of FIG. Part 5
3 is discharged through the lower liquid flow passage 2b,
It becomes the state of E. Then, a measuring portion 5 similar to the above is formed on the piston insertion hole 3b. This measuring unit 5 follows the same operation as that of B to D in FIG. 3, and becomes the state of A in FIG. 3 in which the original measuring unit 5 is on the upper side. Therefore, it is possible to supply a predetermined amount of the chemical liquid to the test tube 10 through the injection port 9 every time the rotary shaft 3 makes a half rotation.

In this embodiment, the liquid quantitative supply device 1 has the liquid bag 7 in which a soft nylon bag is filled with the chemical liquid is suspended, but an appropriate pump mechanism is used as a means for injecting the liquid. Alternatively, it is also suitable to put the liquid in the bellows container, place a weight on the bellows container and apply a pressure depending on the implementation.

Next, a second embodiment of the present invention will be described with reference to FIG. The same members as those in the first embodiment are designated by the same reference numerals, and the duplicated description will be omitted.

In FIG. 4, a through hole 2d for accommodating the rotary shaft 3 is formed on one side surface of the body 2 and the through hole 2d is formed.
A rotary shaft 3 having stepped portions 3a formed at both ends to be inserted into is provided, and bearing plates 6 are fixed to both side surfaces of the body 2 via the stepped portions 3a formed at the both ends. In the second embodiment, the rotary shaft 3 is supported at both ends as opposed to the cantilever support system of the rotary shaft 3 in the first embodiment, and can be appropriately selected depending on the implementation.

[0015]

As described above, according to the present invention, the body main body is formed with the accommodating portion of the rotary shaft having the measuring portion, and the liquid flow passage communicating with the measuring portion is formed. Since the free piston, which can be moved up and down in accordance with the rotation of the rotary shaft, is inserted in the metering unit, the structure is simpler than that of the conventional tube pump and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory view of a first embodiment of a liquid constant quantity supply device embodying the present invention as viewed from above.

FIG. 2 is a cross-sectional explanatory diagram of FIG.

FIG. 3 is an operation explanatory view of the liquid constant quantity supply device of the present invention.

FIG. 4 is a cross-sectional explanatory view of a second embodiment of a liquid constant quantity supply device embodying the present invention.

FIG. 5 is a cross-sectional explanatory view of a conventional tube pump.

[Explanation of symbols]

 1 Liquid fixed amount supply device 2 Body main body 2a Storage part 2b Liquid flow passage 3 Rotating shaft 4 Free piston 5 Measuring part

Claims (1)

[Claims] 1. A body main body 2 is formed with an accommodating portion 2a of a rotary shaft 3 provided with a measuring portion 5, and a liquid flow passage 2b communicating with the measuring portion 5 is bored therein. A liquid constant quantity supply device in which a free piston 4 which is movable up and down in accordance with the rotation of the rotary shaft 3 is inserted.