JPH0413643Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a pinhole detector for a bottle stopper with a built-in rubber stopper with a pull ring.

BACKGROUND TECHNOLOGY Recently, bottles, such as infusion bottles, have been used as mouth plugs.
For example, as shown in Fig. 4, a so-called plug with a built-in rubber plug with a pull ring has become popular, in which a rubber plug a is covered with a plastic film b and a pull ring c is provided on the covered portion of the top surface of the rubber plug a. , a pull ring c is attached to the plastic membrane b covering the top surface of the rubber stopper a.
A groove (not shown) is provided for tearing off the material. This groove part is thin, for example, 0.2 to 0.3 mm.
Therefore, pinholes may occur for some reason during or after molding. If a pinhole occurs, the water inside the can will enter through the pinhole while the bottle is passing through the continuous sterilization machine and adhere to the area around the rubber stopper, resulting in a serious complaint regardless of the amount of water adhered to the product, so this should be detected. It is necessary to eliminate it. As a means for detecting such pinholes, for example, a detector incorporating a known capacitance type proximity switch may be applied. In this case, as is clear from the detection principle diagram in FIG.
(electrodes), the capacitance C between the electrodes A and B changes depending on whether there is water intrusion or not, so by operating the proximity switch based on this capacitance change, In principle, it is possible to detect the presence or absence of pinholes.

Problems to be Solved by the Invention However, as shown in Fig. 4, there is a pull ring c on the top of the spout where the electrode of the detector comes into contact, and furthermore, the top of the plastic membrane b is
Rubber stopper a is not smooth due to unevenness d such as the needle mark on the top surface, and the pull ring c has to be held with a finger, and the electrode part is raised above the top surface except for the connecting part. Variations in the contact area and distance between electrodes are likely to occur, and these variations have a significant impact on the capacitance between the electrodes.
This causes a large detection error and causes a big problem in terms of performance.

The present invention was made with the aim of eliminating these conventional problems.

Means for Solving the Problems The present invention provides a capacitance type proximity device comprising an oscillation circuit that oscillates or stops depending on a change in capacitance, and a capacitor electrode portion electrically connected to the oscillation circuit. The head of the electrode part of the proximity switch has a built-in switch, and the head of the electrode part of the proximity switch is protruded so as to pass through the pull ring of the bottle's stopper with a built-in rubber stopper and come into contact with the top surface of the stopper. , the surface that touches the top of the spout is made of a conductive elastic material,
Built-in rubber stopper with a pull ring for a bottle characterized by being equipped with an electrically insulating ring presser that presses the pull ring against the top surface of the spout when the contact surface of the electrode portion contacts the top surface of the spout. This relates to the pinhole detector in the mold opening part.

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings. Although the figure shows an example of the present invention in which a commercially available detector is partially improved to improve its detection performance, the present invention is not limited to such an example. Various changes are possible without departing from the gist of the invention.

The detector main body 1 includes an oscillation circuit (not shown) that oscillates or stops depending on a change in capacitance, and a capacitance type proximity switch that includes a capacitor electrode part 2a electrically connected to the oscillation circuit. The detector main body 1 itself is easily available as a commercial product. 2b connects the electrode portion 2a to the electrically insulating layer 2.
It is the earth pole part surrounding via c.

A cylindrical earth pole member 3 having approximately the same diameter as the body of the detector main body 1 is fitted and fixed to the previous earth pole portion 2b in a central hole 3b of a central partition 3a. By largely surrounding the electrode portion 2a with the ground pole member 3, noise components can be removed from the electrode portion 2a.
It is possible to more reliably prevent adverse effects on Part 3
For example, one made of brass can be used.

An electrically insulating head base 4 made of, for example, Bakelite and having a circular protrusion 4a at the center of the upper surface is fitted into the upper space of the earth electrode member 3.
An electrically insulating ring presser 5 is fitted into the central hole 5a of the protrusion 4a. The ring presser 5 is preferably made of an elastic material, such as elastic rubber or plastic. The ring presser 5 may be omitted and may also be used as the head base 4.

The outer diameter of the circular protrusion 4a of the head base 4 is smaller than the inner diameter of the pull ring c of the spout (see Fig. 4).
An electrode head 6 having the same shape as the circular protrusion 4a and a conductive elastic disk 7 are successively laminated and fixed on the top surface of the circular protrusion 4a. As the fixing means, for example, an adhesive is used, and for fixing the electrode head 6 and the elastic disk 7, a conductive adhesive is used. The conductive elastic disk 7 may be made of rubber into which conductive powder such as carbon is kneaded. This disk 7 constitutes the elastic contact surface of the electrode head 6.

The electrode head 6 and the electrode part 2a of the main body 1 are connected by a shielded wire 8, one end of the shielded part 8a of the wire 8 is connected to the ground pole part 2b, and the other end is terminated slightly before the electrode head 6. .

The protruding height of the electrode head 6 (including the contact surface) is
The width is approximately equal to the vertical width of the pull ring c, and when the electrode head 6 is pressed against the top surface of the spout portion, the ring presser 5 presses the pull ring c against the top surface of the spout portion.

FIG. 8 shows the operation of detecting the presence or absence of a pinhole using the detector of the present invention. Incidentally, during this detection operation, a grounding member e (electrode) is attached to the circumferential side of the spout, particularly surrounding the built-in portion of the rubber plug. This grounding member e is composed of a pair of left and right half-rings, and can be configured to be pressed against the circumferential side of the spout by a spring bias.

The electrode head 6 of the detector main body 1 passes through the pull ring c and is pressed against the center of the top surface of the spout so as to form a pair with the ground member e. Since the contact surface of the electrode head 6 is composed of a conductive elastic disk 7, the electrode head 6 can be moved through the elastic disk 7 without being affected by irregularities on the top surface of the spout. , the entire surface of the spout can be brought into full contact with the top surface of the spout, and a uniform contact area can be obtained for each operation. Furthermore, since irregularities on the top surface of the spout can be corrected and absorbed by the elastic deformation of the contact surface of the electrode head 6, the distance from the ground member e (electrode) can be made uniform for each operation. Furthermore, if the pull ring c is left in an unstable state such as floating above the top surface of the spout, this may cause variations in the dielectric constant of the insulator between the electrodes. This pull ring c is held by the ring presser 5.
Since it is always pressed against the top surface of the spout, there is no cause for variation in dielectric constant.

Effects As described above, according to the present invention, it is possible to eliminate error factors that affect the size of the capacitance created between the electrodes, so the detection performance is significantly improved.
It has the advantage of being able to reliably detect even small pinholes that may cause the intrusion of ultra-trace amounts of water, and detecting the presence or absence of pinholes without malfunction.

[Brief explanation of the drawing]

Fig. 1 is a partially longitudinal side view showing an embodiment of the present invention, Fig. 2 is an exploded perspective view thereof, Fig. 3 is a longitudinal sectional view showing the situation during detection operation, and Fig. 4 is a view of the spout. A vertical cross-sectional view showing the structure, and FIG. 5 is an explanatory diagram of the detection principle. In the figure, 1 is the detector body, 2a is the electrode part, and 3
4 is a ground pole member, 4 is a head base, 5 is a ring holder, 6 is an electrode head, and 7 is an elastic disc.

Claims (1)

[Scope of utility model registration request] It has a built-in capacitive proximity switch that includes an oscillation circuit that oscillates or stops depending on the change in capacitance, and a capacitor electrode section that is electrically connected to the oscillation circuit. The head is
It protrudes so that it can pass through the pull ring of the bottle's built-in rubber stopper with a pull ring and come into contact with the top surface of the spout, and the surface that contacts the top surface of the spout has a conductive A bottle comprising an electrically insulating ring holder that is made of an elastic material and presses the pull ring against the top surface of the spout when the contact surface of the electrode portion contacts the top surface of the spout. A pinhole detector for the spout with a built-in rubber plug with a pull ring.