JPH082580Y2 - Piston prober piston position detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an improvement of a piston position detecting device of a piston prober used for verification of various flow meters.

(Prior Art) The piston position detection device of the piston prober is
Some are disclosed in Japanese Patent Publication No. 56-31713. According to this piston prober, a container that allows the inside to be visually inspected is provided at the end of the reference volume tube, and when the piston position detection member enters the container as the piston moves, the piston moves to the slide limit position. It is a piston position detection device that can visually detect that it has moved up to.

(Problems to be solved by the invention) However, since the function of the container in the conventional device must be a container having an internal visible structure and pressure resistance, a material such as tempered glass is limited. In addition, there is a problem that the manufacturing cost becomes high because the structure becomes complicated. In addition, there is a drawback that it becomes difficult to see due to dirt of the fluid used, and in a verification vehicle equipped with a piston prober, it is necessary to go to the reference volume tube each time, so workability is extremely poor. Is occurring. The present invention has been devised to solve these problems.

(Means for Solving the Problem) In order to achieve this object, a first invention is to connect a reference volume pipe to a flow meter to be tested, and use a fluid passing through the flow meter to be tested to provide a piston in the reference volume pipe. A container provided at one piston sliding limit position of one of the reference volume pipes in a piston prober configured to test the flow rate measurement accuracy of the flowmeter to be tested based on the volume of fluid removed by the piston. And a piston position detection member which is provided so as to be able to move in and out of the container and which enters the container when the piston reaches the one sliding limit position, and is fixed to an end portion of the piston position detection member. A piston position detecting device for a piston prober, comprising a drive magnet and a driven magnet which is disposed outside the container and is slidably provided so as to follow the drive magnet.

A second invention is such that a proximity switch is provided in the vicinity of the driven magnet, an indicator is connected to the proximity switch, and the indicator displays when the piston reaches one sliding limit position. 2 is a piston position detecting device for a piston prober having the configuration of the first invention.

(Operation) When the piston 3 moves in the reference volume tube 2 and reaches the vicinity of one sliding limit position, the piston 3 becomes a piston position detecting member.
The piston position detecting member 16 is pushed out against the spring 18 against the spring 18, and comes into contact with the stopper member 2b to stop. At the same time, the driven magnet 24 arranged outside the container 14 slides following the drive magnet 22 in the container 14. This state can be visually observed from the outside of the transparent protective cover 28, and it can be confirmed whether or not the piston 3 in the reference volume tube 2 has moved to the stopper member 2b. Further, when the driven magnet 24 moves and approaches the predetermined position of the proximity switch 26 by the above-described operation, the proximity switch 26 operates and the indicator 30 connected thereto lights up. Further, the same operation is performed when the piston 3 in the reference volume tube 2 moves to another sliding limit position.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. Second
In the figure, reference numeral 1 denotes a piston prober, in which a piston 3 is slidably fitted between a stopper member 2a and a stopper member 2b inside a cylindrical reference volume tube 2, and the piston 3 is attached to the stopper member 2a. The section that moves from the to the stopper member 2b is the reference volume section 5, and the volume of the reference volume section 5 is accurately measured in advance.

On the other hand, the inflow ports 2c, 2 are provided outside the reference volume section 5.
d is provided, and the inflow and outflow ports 2c and 2d are connected to the four-way switching valve mechanism 7 by piping. The inflow side of the 4-way switching valve mechanism 7 is connected with the flowmeter 4 to be tested, the pump 6, and the liquid storage tank 8 via a valve 9, and the discharge side of the 4-way switching valve mechanism 7 is connected via a valve 10. It is connected to the liquid storage tank 8 by piping.

Next, the essential part of the present invention will be described with reference to FIGS. 1 and 2. Reference numerals 13 and 14 denote containers attached to the side plates 19 and 20, respectively, provided at both ends of the reference volume tube 2. Reference numerals 15 and 16 denote piston position detecting members, which penetrate the side plates 19 and 20 respectively at both ends of the reference volume tube 2 and are held in the containers 13 and 14 so that they can freely move in and out. The magnets 21 and 22 are fixed. Further, the piston position detecting members 15 and 16 are biased by springs 17 and 18 in a direction of retreating from the inside of the containers 13 and 14, respectively, and their rear ends project into the reference volume section 5. Furthermore, a driven magnet is attached to the outer circumference of the containers 13 and 14.
23 and 24 are fitted and are configured to slide movably following the advance and retreat of the drive magnets 21 and 22. Protective covers 27 and 28 are made of a transparent material.
In the vicinity of the driven magnets 23 and 24, the proximity switch 2
5, 26 (eg reed switch) are mounted and the proximity switches 25, 26 are electrically connected to the indicators 29, 30 (eg indicator lamp).

The operation and action of the piston prober thus configured will be described.

In the state before the start of the verification, the piston 3 has the stopper member 2a.
The reference volume tube 2 is densely filled with liquid. At the start of the test, start pump 6
When the one-way switching valve mechanism 7 is switched, the liquid is passed by the pump 6 through the flowmeter 4 to be tested and the valve 9 and the inflow / outflow port via the pipe 11.
It is supplied to the reference volume tube 2 from 2c. Therefore, the piston 3 (shown by the one-dot chain line in the figure) at the sliding limit position on the left side in FIG. 2 of the reference volume tube 2 is pressed by the supplied liquid and displaced to the right side in the figure. The liquid removed from the reference volume tube 2 with the movement of the piston 3 is discharged from the inflow / outflow port 2d to the outside of the reference volume tube 2 through the pipe 12, and passes through the 4-way switching valve mechanism 7 and the valve 10 to store the liquid. It is refluxed in the tank 8. Piston 3
Moves in the reference volume section 5 and is displaced until it comes into contact with and is locked by the stopper member 2b, and stops at the sliding limit position shown by the two-dot chain line in FIG.

At this time, when the piston 3 arrives in the vicinity of the right end of the reference volume tube 2, the piston 3 contacts the piston position detecting member 16 and resists the spring 18 to move the piston position detecting member 16 to the first position.
It is pushed to the right in the figure and stopped when it comes into contact with the stopper member 2b. At the same time, the driven magnet 24 disposed outside the container 14 and the drive magnet 22 inside the container 14 are moved to the right in the figure. This state can be visually observed from the outside of the transparent protective cover 28, and it can be confirmed whether or not the piston 3 in the reference volume tube 2 has moved to the stopper member 2b. Further, when the driven magnet 24 moves and reaches the predetermined position of the proximity switch 26 by the above-mentioned operation, the proximity switch 26
Is activated, and the indicator 30 connected thereto is lit.

In the piston prober 1 with this configuration, the piston 3
The volume of the liquid removed from within the reference volume section 5 while moving from the stopper member 2a to the stopper member 2b is equal to the liquid that actually passed through the flowmeter 4 to be tested. Therefore, by comparing the count value of the counter of the flow meter 4 to be tested with the volume of the reference volume section 5, the instrumental difference or measurement accuracy of the flow meter 4 to be tested can be verified. In addition, it can be confirmed visually or by the indicator 30 that the piston 3 has moved in the reference volume section 5 and has reached the one sliding limit position, and during verification, for example, the reference volume It is also possible to detect an abnormality such as the piston 3 stopping in the tube 2.

In order to return the piston 3 that has moved to the right end portion of the reference volume tube 2 to the original position again, the four-way switching valve mechanism 7 is switched, and contrary to the above case, the inside of the reference volume tube 2 is connected via the pipe 12. It is sufficient to supply the liquid to.

(Effects of the Invention) As is apparent from the above embodiments, the present invention has a container provided at one piston sliding limit position of the reference volume tube and a piston provided so as to be able to move in and out of the container. A piston position detection member that enters the container when it reaches one sliding limit position, a drive magnet fixed to the end of the piston position detection member, and arranged outside the container to follow the drive magnet. And a piston position detection device for a piston prober consisting of a driven magnet slidably provided,
Further, a proximity switch is provided near the driven magnet, an indicator is connected to the proximity switch, and the indicator is displayed when the piston reaches one sliding limit position. It is a position detection device.

The container in this device does not need to be visually inspected, and it only needs to have a pressure resistant function, so the structure is simple and it can be manufactured at low cost, and when dangerous liquids are used because glass is not used as in the past. But it's extremely safe. In addition, since it is possible to display remotely using a driven magnet, even in the case of a mobile verification vehicle equipped with a reference volume tube, for example, it is not necessary to go into the vehicle each time and check it visually so that it can be seen easily. Since a display device can be installed, the verification work is quick, and the safety is great.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of an essential part showing an embodiment of the present invention, and FIG. 2 is a schematic configuration diagram of a piston prober of the present invention. 1: Piston prober, 2: Standard volume tube 2a, 2b: Stopper member, 2c, 2d: Inlet / outlet 3: Piston, 4: Flow meter to be tested 5: Standard volume section, 6: Pump 7: 4-way switching valve mechanism , 8: Storage tank 9, 10: Valve, 11, 12: Piping 13, 14: Container, 15, 16: Piston position detection member 17, 18: Spring, 19, 20: Side plate 21, 22: Drive magnet, 23 , 24: Driven magnet 25, 26: Proximity switch, 27, 28: Protective cover 29, 30: Display

Claims (2)

[Scope of utility model registration request] 1. A reference volume pipe is connected to a flowmeter to be tested, a piston in the reference volume pipe is moved by a fluid passing through the flowmeter to be tested, and the volume of fluid removed by the piston is used as a reference. In a piston prober configured to verify the flow rate measurement accuracy of a flow meter, a container provided at one piston sliding limit position of the reference volume tube and a piston provided so as to be able to move in and out of the container are Piston position detection member that enters the container when it reaches the sliding limit position, a drive magnet fixed to the end of the piston position detection member, and arranged outside the container to follow the drive magnet. A piston position detecting device for a piston prober, comprising a driven magnet slidably provided. 2. A proximity switch is arranged in the vicinity of the driven magnet, an indicator is connected to the proximity switch, and the indicator indicates when the piston reaches one piston slide limit position. The piston position detecting device for a piston prober according to claim 1.