JPH0472689B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for molding a gasket of plastic material onto a cap, such as a screw cap, crown or the like, consisting of a cup.

As a conventional technique for molding a cap gasket in the manufacture of crowns, a method is known in which a predetermined amount of a plastic material is introduced into the metal cap of the crown by extrusion, generally in a soft state, and then molded at room temperature. All of the machines used to carry out these prior art techniques have the problem that, if the height of the cap is too large, it is not possible to fully introduce the extruded and metered plastic material into the cap. . The equipment traditionally used to form gaskets consists of a first carousel carrying a plurality of metal cups around its periphery.
and a rotary knife device configured to act in a connecting direction with respect to the path of travel of the second carousel or cup to be fed with metered plastic material.

In both cases, the part that serves to introduce the metered plastic material is clearly of limited length, so the need for the device to operate at high speeds increases the complexity of the device and the probability of forming a defective gasket. It also becomes more expensive.

Obviously, this also limits the rotational speed of the carousel or the speed of the introduction device and thus the output speed of the device.

It is therefore an object of the present invention to provide screw caps, crowns, etc., which can be operated at high speed and ensure a reliable seal even if the height dimension of the metal cup is quite large.
It is an object of the present invention to obviate these drawbacks of the prior art by providing a device for forming a gasket on a base consisting of a cup.

According to one aspect of the present invention, the above problems and objects, as well as other objects which will become more apparent below, provide for a carousel carrying a plurality of cups disposed on its outer periphery, and a carousel for carrying a plurality of cups disposed on its outer periphery; scooping and measuring the plastic material, each forming a spoon member supported concentrically with the cup and oriented in the direction of rotation of the carousel, and configured to communicate with either the suction device or the blowout device; a plastic material extrusion nozzle fixed relative to the carousel and open toward the scooping and metering device; and continuously driving the scooping and metering device between a raised position and a lowered position. in the raised position, the plastic material is scooped up and measured by the spoon member, the scooping and measuring device is communicated with the suction device to hold the measured amount of the plastic material, and the scooping and measuring device is in communication with the suction device to hold the measured amount of plastic material, and is lowered. At the position, the metered amount of plastic material is introduced into the cup, and the scooping and metering device is in communication with the blowing device to spread the metered amount of plastic material into the cup. This is accomplished by means of a device that molds a gasket of plastic material onto a cap consisting of a cup, such as a screw cap, crown or the like.

The invention will be more clearly understood from the following detailed description of the preferred embodiments, taken in conjunction with the accompanying drawings.

With reference to the accompanying drawings, the device of the invention consists of a carousel 1 which can carry a plurality of metal caps 2 on its outer periphery and cooperates with an extrusion head 3 for plastic material. The extrusion head 3 is fixed relative to the carousel 1.

The carousel 1 includes a plate 4 fixed to a vertical shaft 5. The shaft 5 has a rotation bearing 6
via which it is rotatably mounted in a sleeve 7 which is part of the fixed frame of the device.

The plate 4 has a plurality of grips 8 configured to grip the cup 2. As shown in detail in FIG. 2, each gripping portion 8 has a fixed pawl 9a and a movable pawl 9.
It consists of b. The movable pawl 9b is attached to a pin 10 with a return spring 11 and an idler roller 1
I support 2. The roller 12 meshes with an annular cam 13 formed on the top of the sleeve 7, and the cam 13 controls the opening of the movable pawl 9b of the grip portion 8.

At the top of the plate 4 is a generally cylindrical body 15.
is fixed by a screw element 14. The outer periphery of the body 15 is provided with vertical seats, each concentric with the axis of the cup 2 supported on the plate 4, on each of which a device for scooping, measuring and feeding the plastic material to the cup 2 is slid. movably mounted (this device is hereinafter simply referred to as a batcher).

Each batch is an axially bored cylinder 16
The bottom of the cylinder 16 is connected to the circular conveyor 1.
The spoon member 17 is oriented in the direction of rotation. The spoon member 17 is preferably made by longitudinally cutting a narrow tubular portion of the cylinder 16, so that the spoon member 17 has a hollow semi-cylindrical shape. A small tube 18 slidable in the axial direction of the cylinder 16
is attached, and its bottom end is open to open the spoon member 1.
7 and its upper end communicates with a hole 20 formed in the guide 21 via a fitting 19 . The guide 21 is attached to the flat part 16 of the cylinder 16 so that it can slide up and down in a direction parallel to the rotation axis of the circular conveyor.
It is accommodated in the seat portion 16a of b.

The cylinder 16 is driven up and down by a cam 22 that engages a roller 23 carried on the top of the flat 16. The small tube 18 has another cam 24 which engages another roller 25 carried at the top of the guide 21.
is driven against the cylinder 16 by.

The cams 22 and 24 are annularly formed on the outer surface of a drum 26, which is mounted on the body 15 concentrically with the shaft 5 and fixedly relative to the carousel 1.

The guide 21 has a first hole 20 extending radially inside the body 15 and opening up and down on the outer surface of the body 15.
or a second conduit 28 .

Conduit 27 is configured to communicate with the air intake device and conduit 28 is configured to communicate with the air blowing device. For this purpose, the conduits 27, 28 are opened at the upper side of the body 15;
controlled by ring 29. Ring 29 has a seal and is recessed in drum 26.
Connecting pipes 30 for connecting to the intake and blowing devices are installed in the drum 26 at different angles (only one of which is shown in the drawing). A flange 31 is formed near the top of the sleeve 7, which serves as a support for a ring 32 that supports RF heating means, which are known per se. Ring 32 is circular conveyor 1
It is placed directly under the metal cup 2 supported by. To prevent friction with the ring 32, the cup 2 is held by the grip 8 slightly away from the ring 32. The plastics extrusion head 3 comprises a nozzle 3a extending above the cup 2 carried on the carousel 1, the nozzle 3a having a vertically upwardly directed plastics delivery conduit and a spoon member 17 by which it passes. It consists of an orifice that is doctored.

The device of the invention described above works as follows. As the carousel 1 rotates, the cylinder 16 is driven via the fixed cam 22 to move continuously between the raised position and the lowered position. In the raised position, the cylinder 16 passes through the extrusion nozzle 3a and scoops up and meters out the plastic material, which is simultaneously distributed by the extruder, by means of a corresponding spoon member 17. At this stage, the corresponding small tube 18 is the spoon member 17.
The small tube 18 is in communication with a suction device via a conduit 27 to evacuate the spoon member 17 and retain the amount of plastic material scooped into the spoon member 17. Subsequently, the cylinder 16 is lowered under the control of the cam 22, and the spoon 17 is introduced into the metal cup 2 held in the grip 8. At the same time, the small tube 18 is also lowered by the drive of the cam 24. However, the tube 18 moves further below the cylinder 16, and the tube 18 moves further below the cylinder 16, mechanically separating the scooped and metered plastic material from the spoon member 17. When moving to the lowered position, the small tube 1
8 communicates with a conduit 28 via which the small tube 18 communicates with the blowing device. In this way, the desired amount of plastic material is introduced via the ring 32 into the suitably heated metal cup 2. By blowing from a blowing device such as a compressor,
The scooped and metered plastic material can be spread over the bottom of the metal cup, so that the gasket of the cap is well formed. The step of introducing a predetermined amount of plastic material into the metal cup 2 after it has been scooped up from the extrusion nozzle 3 by the spoon member 17 is carried out on the wide rotational arc of the carousel 1.
It is completed between the position occupied by the extrusion nozzle 3 and the usual die exit station of the carousel.

Thus, the present invention achieves the intended objectives of high speed operation and defect-free gasket formation.

[Brief explanation of the drawing]

FIG. 1 is a partially omitted axial sectional view of the apparatus of the present invention, and FIG. 2 is a detailed plan view of the gripping portion of the circular conveyor in the apparatus. In the figure, 1 is a circular conveyor, 2 is a metal cup, 3
is a plastic material extrusion head, 3a is an orifice,
4 is a plate, 16 is a cylinder, 17 is a spoon member, 18 is a small tube, 20 is a hole, 21 is a guide, 2
2 is a cam, 23 is a roller, 24 is a cam, 25 is a roller, and 27 and 28 are conduits.

Claims (1)

[Scope of Claims] 1. A circular conveyor carrying a plurality of cups disposed on the outer periphery, each supported slidably on the circular conveyor and concentrically with the cups, and oriented in the rotational direction of the circular conveyor. a device for scooping up and weighing a plastic material, which is a spoon member that is connected to either the suction device or the blowout device; and a device for continuously driving the scooping and metering device between a raised position and a lowered position, in which the plastic material is scooped and measured by the spoon member in the raised position. the scooping and metering device is in communication with the suction device to hold the calculated amount of plastic material, and in the lowered position the metered plastic material is introduced into the cup and the scooping and metering device is in communication with the suction device to retain the calculated amount of plastic material; A gasket of plastic material in a cap consisting of a cup, such as a screw lid or a crown, characterized in that a metering device is configured to communicate with the blowing device so that the measured amount of plastic material is spread into the cup. A device that molds. 2. Each scooping and measuring device consists of a cylinder, a spoon member is formed at the bottom of the cylinder, and a small tube whose bottom end opens into the spoon member is slidably housed inside the cylinder, and the cylinder and the The tubule is connected to the cam so that when the cylinder is in the raised position, the tubule rises above the spoon member and is in communication with the intake device, and when the cylinder is in the lowered position, the tubule engages the spoon member and is in communication with the blowout device. An apparatus for forming a gasket of a plastic material on a base consisting of a cup, such as a screw cap, a crown, etc., as claimed in claim 1, which is driven by the above-mentioned method. 3 a plastic material delivery conduit with an extrusion nozzle facing vertically upward and disposed below the spoon member;
Claim 2, comprising an orifice configured to be scraped off by a spoon member.
A device for molding a gasket of plastic material onto a cap consisting of a cup, such as a screw cap or crown as described in Section 1. 4. The circular conveyor consists of a plate having a gripping portion for gripping cups attached to the outer periphery, and a body attached to the top of the plate, and a vertical seat on which each of the cylinders is slidably attached. and a plurality of pairs of conduits arranged one above the other are formed, the upper one communicating the small tube with the intake device in the cylinder up position, and the lower one communicating the small tube with the intake device in the cylinder down position. An apparatus for molding a gasket of plastic material onto a cap consisting of a cup, such as a screw cap or a crown, as claimed in claim 2, which is configured to communicate with a blowing device. 5. A screw lid, a crown, etc. from a cup according to claim 1, which is fixedly held with respect to a circular conveyor and is provided with a heating device disposed below the cup carried on the circular conveyor. A device that molds a gasket made of plastic material into a base made of plastic.