GB2091242A

GB2091242A - Take-out tong head for use in glassware forming machinery

Info

Publication number: GB2091242A
Application number: GB8202644A
Authority: GB
Original assignee: Rockware Glass Ltd
Current assignee: Ardagh Glass Ltd
Priority date: 1978-04-20
Filing date: 1979-05-08
Publication date: 1982-07-28
Also published as: GB2091242B

Abstract

A take-out tong head is described for use in an independent section glass forming machine, in which after the final moulding operation, while the glassware is cooling in the mould after forming, the blow head is removed and the take- out tongs (18) are brought to a position above the mould so that when the mould is split, any tendency to sticking of the ware in the mould is counteracted by the ware engaging one of the tong jaws and releasing from the mould. Thereafter, the tongs are lowered, and caused to grip the ware and remove it in the usual way. The tong head comprises first (7, 5) and second (16, 14) piston cylinder devices adapted to operate in this way. <IMAGE>

Description

SPECIFICATION Take-out tong head for use in glassware forming machinery This invention relates to take-out tongs for use in glassware forming machinery.

In recent years the use has become widespread of so-called independent section glassforming machines for the manufacture of glass containers such as bottles and jars. Such machines are located adjacent a forehearth of a glass making furnace and are fed with gobs of glass from the forehearth. From such gobs the hollow glassware is first formed into a parison and thereafter blown to shape in a mould. After blowing to shape and as soon as the ware is sufficiently cooled to be sufficiently rigid to enable it to be handled, it is removed from the mould by means of socalied take-out tongs and placed on a dead plate prior to being transferred to a conveyor which conventionally leads the newly formed glassware into an annealing lehr.

The conventional operation of the final container moulding stage is as follows: the moulds are formed as two half moulds which are regularly opened and closed. Each mould half may have one or two cavities therein. The mould is first opened and a parison moved into position by an appropriate arm. The mould is then closed and the parison gripped by the upper end of the mould engaging the underside of the rim of the glass container. A so-called blow head is then located above the mould and air is introduced via the blow head into the centre of the parison so blowing the molten glass walls against the walls of the mould. After a sufficient period of time has elapsed to enable the glass in contact with the mould walls to cool sufficiently to render the container self-supporting, the blow head is raised very slightly and the mould halves parted.The halves are parted before the blow head is raised entirely in order that any tendency of a container to stick in one half of a mould is counteracted by the upper edge of the container abutting the side of the blow head which frees any container slightly adherent to a half of the mould. The blow head is then raised and take-out tongs lowered over the heads of the glassware. The tongs are then operated to grip the glassware around its periphery under its upper rim, pick it up and deposit it on a dead plate prior to its transfer to the exit conveyor.

In order to produce yet greater numbers of containers per hour on such machines, it is desired to shorten the time taken for each operational step but this has adverse results when that operational step is the cooling of the blow glassware in the mould with the mould halves remaining assembled together.

We have now found that the time available for cooling the glassware in this way may be substantially increased if the blow head is removed immediately after the glassware has been blown to shape and the take-out tongs and their positioning modified to act to release any ware tending to stick in the mould when the mould halves are separated. Operating in this way enables the separation of the mould halves to be delayed until the tongs close operation.

Our co-pending Application No. 7915770 from which this Application is divided describes and claims a method of operating an independent section glass forming machine in each section of which one or more glass containers have an upper peripheral rim are finally moulded to shape in a blow mould having two mating halves by means of gas e.g. air pressure applied through a blow head, which comprises the steps of blowing the glassware to shape in the mould, removing the blowhead from a position above the mould, positioning one or more take out tongs above the mould with jaws thereon located laterally adjacent to an upper part of the container(s) projecting from the mould, parting the mould halves to release the container(s), further lowering the jaws of the take out tong(s), engaging the jaws of the take out tong(s) underneath the rim of the container(s) and transferring the container(s) by means of the tong(s) out of the machine.

The tongs are preferably pneumatically operated and mounted upon an intermediate base member itself mounted on a base. The intermediate base member may be arranged to move up and down a short distance relative to the base by means of a piston/cylinder arrangement. In use the base is first brought into position after removal of the blowhead over the glassware forming mould with the intermediate base in its upper position and so that the jaws of the tongs are laterally adjacent the heads of the glassware which protrudes from the upper surface of the mould.

This mould is then split apart, any tendency for the or each glass container therein to stick to one of the mould halves being counteracted by its engagement with a jaw of one of the tongs. Thereafter the piston cylinder arrangement may be operated in order to lower the tongs a short distance whereafter the conventional piston cylinders operating the tongs may be actuated to cause the tong jaws to grip the ware below its upper rim. After this, the base carrying the intermediate base may be moved to lift the ware out of the machine and e.g. on to a deadplate prior to moving it on to a transport conveyor leading the ware to an annealing lehr.

Such movement may be achieved particularly conveniently if the piston cylinder devices operating the take out jaws are fed with compressed air from the main cylinder of the device via ports which are only opened when the intermediate base is moved from the base.

Thus as pneumatic pressure is applied, first the intermediate base moves away from the base i.e. the tong jaws drop downwards and secondly the tongs are caused to operate and grip the ware immediately thereafter. A system of return springs reverses the sequence as soon as the pressure is released.

According to the present invention there is provided a take-out tong head for use in a glassware forming machine which comprises one or more pairs of take out tongs, a first piston/cylinder device adapted to cause the jaws of the tongs to move together when fed with compressed air, a compressed air feed to the first piston/cylinder device from a second piston/cylinder device when the piston of the second piston/cylinder device uncovers a port in the wall of the cylinder of the second piston/cylinder device, and the second piston/cylinder device causing axial movement of the whole of the first piston/cylinder device relative to a base member.Preferably such apparatus has associated with each piston/ cylinder device a return spring for returning the piston and cylinder to their initial relative positions once the second piston/cylinder device is no longer fed with compressed fluid, preferably compressed air.

The invention is illustrated by way of example with reference to the accompanying drawings in which: Figure 1 is a partial section in side view of a take out tong apparatus according to the present invention along the lines X-X on Fig.

2, and Figure 2 is a front view of the apparatus of Fig. 1.

Referring to the drawings, the apparatus comprises a base member 5 attached to a suitable arm enabling the base member to be swung into position. The base member is bored to provide a central cylinder 1 6 in which slides a piston 1 3 sealed to the cylinder wall by piston rings 14. The piston 1 3 is mounted on a piston rod 11 carrying a pair of locking units 1 2 on its upper end and a carrier plate 9 on its lower end, plate 9 being secured by a lock unit 15.

Plate 9 carries mountings 10 which have a pair of lever arms 1 7 set therein. The lower ends of arms 1 7 bear tongheads 1 8 which in use contact the neck of a just moulded container. The upper ends of arms 1 7 are pivoted to links 1 9 which in turn are pivotally connected together and to the lower end of a piston rod 1.

The piston rod 1 bears a piston 7 sealed to a lateral cylinder in base member 5 by means of piston rings 6. The upper end of piston rod 1 bears a retaining washer 2 and is surrounded by a compression spring 3 which seats on a guide bush 4 and urges rod 1 upwards. The lower ends of the three cylinders in base member 5 are constituted by a perforated faceplate 8. The central cylinder in base member 5 is conncted to the two lateral cylinders by ports 20, only uncovered when piston 1 3 is in its lower position.

When piston 1 is in its upper position, tongheads 1 8 are apart.

The operation of the apparatus is as follows: the base member 5 is first moved into position with the pistons as shown in Fig. 1. The position is one in which the top of the newly moulded ware, protruding from the mould, lies between open tongheads 18. The ware is during this movement in the closed mould and rapidly losing heat. When the base member is so positioned, the mould is split apart and any ware adherent to one of the mould halves is prevented from sticking in that mould half by contact with one of tong heads 18. Air is now fed to cylinder 16. First plate 9 drops until nuts 1 2 come to rest on the top of base member 5. Then air flows through ports 20 into the side cylinders and lowers pistons 7, in turn causing tong heads 18 to grasp the ware. The whole base member carrying the ware is then moved to a position over an exit conveyor, and the pneumatic pressure relieved. Springs 3 then raise piston rods 1 and so cause the ware to be released on to the conveyor. The base member 5 is then returned to its rest position.

Claims

1. A take out tong head for use in a glassware forming machine which comprises one or more pairs of take out tongs, a first piston/cylinder device adapted to cause the jaws of the tongs to move together when fed with comprssed air, a compressed air feed to the first piston/cylinder device from a second piston/cylinder device when the piston of the second piston/cylinder device uncovers a port in the wall of the cylinder of the second piston/cylinder device, and the second piston/cylinder device causing axial movement of the whole of the first piston/cylinder device relative to a base member.

2. A take out tong head according to claim 1 and including a return spring for returning the pistons and cylinders to their initial relative positions once the second piston/cylinder device is no longer fed with compressed fluid.

2. A take out tong head according to claim 1 wherein, associated with each piston/cylinder device there is a return spring for returning the piston and cylinder to their initial relative positions once the second piston/ cylinder device is no longer fed with compressed fluid.

3. A take out tong head for an independent section glass forming machine substantially as hereinbefore described with reference to the accompanying drawings.

4. An independent section glass forming machine including a take-out tong head according to any of claims 1 to

3.

CLAIMS (8th April 1982)

1. A take out tong head for use in a glassware forming machine which comprises a base member, one or more pairs of take out tongs, a first piston/cylinder device adapted to cause the jaws of the tongs to move together when fed with comprssed air, a compressed air feed to the first piston/cylinder device from a second piston/cylinder device when the piston of the second piston/cylinder device uncovers a port in the wall of the cylinder of the second piston/cylinder device, and the second piston/cylinder device causing axial movement of the piston of the first piston/cylinder device and the jaws of the tongs relative to the base member.