IES81093B2

IES81093B2 - A gasket

Info

Publication number: IES81093B2
Authority: IE
Inventors: John Ryan
Original assignee: Ryan Intellectual Properties L
Priority date: 1999-04-01
Filing date: 1999-04-01
Publication date: 2000-03-08
Also published as: GB9907707D0; GB2348470A; IES990267A2; GB2348470B

Abstract

A method and apparatus is for producing a multi-layer gasket suitable for mounting electronic components to provide absorbency and electrical noise reduction. Carefully aligned and sequenced rollers, drums and cutters are activated to apply the layers and deliver individual gaskets on a carrier ready for use. The process is fully automated and significantly reduces wastage while being flexible to produce a wide variety of gaskets. The method involves forming a laminate in several stages and which entails the removal of a carrier film and a peelable screen during the stages.

Description

“A Gasket” P7928.IES The present invention relates to a gasket and in particular to a method and apparatus for use in the production of multi-layer adhesive gaskets.

A variety of multi-layer gaskets are known for use in applications where shockproof and absorbent mounts are required. These gaskets are particularly effective in situations where it is necessary to reduce to an absolute minimum Electromagnetic and Radio Frequency Interference (EMI & RFI). One particular application where all of these characteristics are required may be illustrated with reference to the production of mobile telephones. To ensure that the telephone operates correctly in all environments a gasket is fitted between a Liquid Crystal Display (LCD) and the telephone casing. In addition to providing the necessary interference protection, it prevents damage to the display during the life of the telephone and prevents ingress of moisture to internal circuitry. Gaskets having different shapes but identical functionality are fitted between the speaker or microphones and the telephone casing.

Heretofore, the production of these gaskets has been labour intensive requiring the intervention during processing of an excessive number of personnel. Additionally, the skill requirements for supervising and equipment operatives were too high. Obviously, both of these have resulted in higher per unit costs, which are unacceptable to equipment manufacturers. Attempts to automate the production process have been limited by their inability to produce the necessary gaskets to the required quality standards or having an uneconomic acceptance to rejection ratio. Where automation has proved possible, the systems have been inflexible to varying customer requirements severely limiting their scope of application.

There is therefore a need for a method and apparatus for the production of a gasket, which will overcome the aforementioned problems.

Accordingly, there is provided a method for producing a multi-layer gasket for use in the mounting of electronic components, the gasket being produced by activating a carrier roller, a layer roller, a web roller, an excess roller, a product roller, a separation drum and a screen drum to deliver materials associated with the said rollers and drums at a pre-set speed to at least two synchronised and aligned cutters, the rollers, drums and cutters performing the sequential steps of: drawing a non-stick earner film from the carrier roller and a double-sided adhesive laminate having a protective layer from the adhesive roller; fixing the carrier film to the laminate to cover substantial portion of the width of the film by drawing the film and laminate through compressing rollers to form a base substrate; passing the base substrate beneath a detachment tensioner to remove the protective layer by winding the protective layer onto the layer roller to produce an adhesive substrate having an exposed adhesive section; applying a silicone based non-stick web to the adhesive portion ofthe adhesive substrate by drawing the non-stick web from the web roller and passing the web and adhesive substrate between a plurality of compressing rollers to form a work substrate; removing selected portions of the work substrate using the a plurality of cutters disposed on and about an exterior surface of the precision substrate-cutting drum to form a perforated substrate; removing the carrier film from the perforated substrate to produce a connect substrate by drawing the film across a separation roller and around the separation drum; affixing a peelable screen to the connect substrate to form a Tollable substrate by drawing the screen from the screen drum and is attaching the screen to a lower adhesive surface of the laminate; passing the Tollable substrate through the shaping cutter to define a gasket outline shape and form a gasket outline substrate, removing material outside the gasket outline from the gasket outline substrate onto the excess roller to produce deliverable gaskets; and winding deliverable gaskets onto the product roller for storage and delivery.

In a particularly preferred embodiment the method comprises the further steps of:removing the protective coating from a plurality of adjacent gaskets using a adhesive material; and applying a single continuous non-adhesive film across unprotected gaskets.

According to another aspect of the invention there is provided an apparatus for producing a multi-layer gasket for use in the mounting of electronic components, the apparatus comprising an a carrier roller, a layer roller, a web roller, an excess roller, a product roller, a separation drum and a screen drum to deliver materials associated with the said rollers and drums at a pre-set speed to at least two synchronised and aligned cutters, the rollers, drums and cutters performing the sequential steps of :drawing a non-stick carrier film from the carrier roller and a double-sided adhesive laminate having a protective layer 43 from the adhesive roller; fixing the carrier film to the laminate to cover substantial portion of the width of the film by drawing the film and laminate through compressing rollers to form a base substrate; passing the base substrate beneath a detachment tensioner to remove the protective layer by winding the protective layer onto the layer roller to produce an adhesive substrate having an exposed adhesive section; applying a silicone based non-stick web to the adhesive portion of the adhesive substrate by drawing the non-stick web from the web roller and passing the web and adhesive substrate between a plurality of compressing rollers to form a work substrate; removing selected portions of the work substrate using the a plurality of cutters disposed on and about an exterior surface of the precision substrate-cutting drum to form a perforated substrate; removing the carrier film from the perforated substrate to produce a connect substrate by drawing the film across a separation roller and around the separation drum; affixing a peelable screen to the connect substrate to form a rollable substrate by drawing the screen from the screen drum and is attaching the screen to a lower adhesive surface of the laminate; passing the rollable substrate through the shaping cutter to define a gasket outline shape and form a gasket outline substrate; removing material outside the gasket outline from the gasket outline substrate onto the excess roller; removing the protective coating from a plurality of adjacent gaskets using a adhesive material; and applying a single continuous non-adhesive film across unprotected gaskets.

The invention will now be described with reference to the accompanying drawings, which shows, by way of example only, one embodiment of a process and apparatus for producing a gasket in which: Fig. 1 is a perspective view of portion of a roll of gaskets produced in accordance with the invention; Fig.2 is a perspective view of an apparatus according to the invention for producing the gaskets of Fig. 1; Fig. 3 is an operational view of the apparatus of Fig. 2; and Figs. 4,4A, 5,5A, 6,6A, 7, 7A, 8,8A, 9, 9A, 10,10A, 11 and 11A show intermediate stages in the construction of the gasket of Fig. 1. Each A stage being a cross section of the corresponding numeral.

Referring to the drawings and initially to Fig. 1, there is shown a gasket in accordance with the invention indicated generally by the reference numeral 1. The gasket 1 may be used for mounting electronic components in systems to provide absorbency and shock proofing as well as reducing electromagnetic and radio frequency interference. The gasket 1, is carried on a peelable screen 91 for delivery to an assembly site where it is easily removed for use in the production of devices such as mobile telephones requiring the use of the gasket 1. Further, the screen 91 can be rolled to aid delivery without dislodging the gasket 1. The construction of the gasket will be described in more detail below.

Fig. 2 shows an apparatus for producing the gasket 1 in accordance with the invention indicated generally by the reference numeral 3. The apparatus 3 comprises a number of rollers namely a carrier roller 4, a layer roller 5, a web roller 6, an excess roller 11, and a product roller 12. The apparatus also includes a separation drum 8 and a screen drum 9.

The apparatus has in this case two cutters, a precision substrate-cutting drum 7 and shaping cutter 10. The alignment and synchronisation of the cutters 7,10 is an essential feature of the invention. Synchronisation is achieved using a common drive (not shown) and alignment guaranteed by careful adjustment of the cutter mountings.

In more detail and referring now to Fig. 3, the rollers are activated to begin production of the gasket I. A non-stick carrier film 41 is drawn from the carrier roller 4 and a doublesided adhesive laminate 42 having a protective layer 43 is simultaneously drawn from the adhesive roller 4A at the same speed. The carrier film 41 is fixed to the laminate 42 covering almost the entire width but leaving an uncovered handling margin 45, by the adhesive surface on the opposite side of the laminate 42 to the protective layer 43. The film 41 and the laminate 42 are fixed as both the film 41 and the laminate 42 are drawn through the first compressing rollers 4B to form a base substrate indicated generally as 44 and shown in detail in Figs. 4 and 4A.

The base substrate is passed beneath a detachment tensioner 51 to remove the protective layer 43 by winding the layer 43 onto the layer roller 5. The presence of the protective layer 43 allows the adhesive laminate 42 to be more easily handled during and stored prior to manufacturing. Downstream of the tensioner 51 with the layer 43 removed, the base substrate 44 becomes an adhesive substrate indicated at 52 with an exposed adhesive portion 53 shown in detail in Figs. 5 and 5A, By producing the adhesive substrate 52 in this way positive contact with the carrier film 41 is guaranteed as the compressing rollers 4B do not come into contact with the adhesive laminate 42 but with the layer 43.

The adhesive substrate 52 is then drawn further through the apparatus 1 and a silicone based non-stick web 61 is affixed to the adhesive portion of 53 of the adhesive substrate 52. The web 61 is drawn from the web roller 6 and securely attached as the substrate 52 and the web 61 are drawn between compressing rollers 62 to form a work substrate shown as 63. The work substrate 63 is shown in detail in Figs. 6 and 6A. The work substrate 63 is passed beneath the precision substrate-cutting drum 7 to form a perforated substrate 71. The cutter drum 7 has cutting templates 72 arranged on and about an exterior surface to extract window blanks 73 leaving required openings 74 in the perforated substrate 71. The perforated substrate 71 results when the window blanks 73 have been collected in a blank bag 79 as illustrated in Figs. 7 and 7A.

The perforated substrate 71 then has the carrier film 41 removed to produce a connect substrate 81. The film 41 is removed by drawing the film 41 across a separation roller 82 and around the separation drum 8. The connect substrate is show particularly in Figs. 8 and 8 A. The connect substrate 81 has the peelable screen 91 applied to form a Tollable substrate 92. The screen 91 is drawn from the screen drum 9 and is fixed to the lower adhesive surface of the laminate 42 as shown in detail in Figs. 9 and 9A.

The rollable substrate 92 is then passed through the shaping cutter 10 to cut the gasket outline shape and form a gasket outline substrate 100 shown in Figs. 10 and 10A. The shaping cutter 10 performs a kiss cut, which is to say a cut which does not pierce the screen 91 but separates the gasket shape from adjacent material carried thereon. This surrounding material is removed to leave the final deliverable gasket 1 by drawing the excess material from the substrate 92 onto the excess roller 11. The screen 91 carrying the gasket 1 is then wound on the product roller 12 for removal and delivery.

It will be understood that to aid production the protective coating for each gasket may be removed with an adhesive material and a continuous film applied if required. This reduces the time required for a operative to isolate a single gasket and ensures that it is ready for application while still protecting the Gaskets own adhesive surfaces.

The invention represents a significant improvement over known production techniques as the various layers are applied sequentially and removed in sequentially under light tension to prevent buckling or imperfect adhesion. Furthermore, the nature of the material on a given deliver device may be easily modified to answer specific requirements. For example, the adhesive laminate described above may be substituted for an adhesive foam laminate. Additionally the shape of the gaskets produced may be easily modified by the simple expedient of replacing cutters on the exterior surface of the drums.

It will of course be understood that the invention is not limited to the specific details as herein described, which are given by way of example only, and that various alterations and modifications may be made without departing from the scope of the invention.

Claims

1. A method for producing a multi-layer gasket for use in the mounting of electronic components, the gasket being produced by activating a carrier roller, a layer roller, a web roller, an excess roller, a product roller, a separation drum and a screen drum to deliver materials associated with the said rollers and drums at a pre-set speed to at least two synchronised and aligned cutters, the rollers, drums and cutters performing the sequential steps of :drawing a non-stick carrier film from the carrier roller and a double-sided adhesive laminate having a protective layer from the adhesive roller; fixing the carrier film to the laminate to cover substantial portion of the width of the film by drawing the film and laminate through compressing rollers to form a base substrate; passing the base substrate beneath a detachment tensioner to remove the protective layer by winding the protective layer onto the layer roller to produce an adhesive substrate having an exposed adhesive section; applying a silicone based non-stick web to the adhesive portion of the adhesive substrate by drawing the non-stick web from the web roller and passing the web and adhesive substrate between a plurality of compressing rollers to form a work substrate; removing selected portions of the work substrate using the a plurality of cutters disposed on and about an exterior surface of the precision substratecutting drum to form a perforated substrate; removing the carrier film from the perforated substrate to produce a connect substrate by drawing the film across a separation roller and around the separation drum; affixing a peelable screen to the connect substrate to form a rollable substrate by drawing the screen from the screen drum and is attaching the screen to a lower adhesive surface of the laminate; passing the rollable substrate through the shaping cutter to define a gasket outline shape and form a gasket outline substrate, removing material outside the gasket outline from the gasket outline substrate onto the excess roller to produce deliverable gaskets; and winding deliverable gaskets onto the product roller for storage and delivery.

2. A method as claimed in claim 1 comprising the further steps oftremoving the protective coating from a plurality of adjacent gaskets using a adhesive material; and applying a single continuous non-adhesive film across unprotected gaskets.

3. A method for producing a gasket or a gasket whenever produced by the process, substantially as herein described with reference to and as shown in the accompanying drawings.

4. A apparatus for producing a multi-layer gasket for use in the mounting of electronic components, the apparatus comprising an a carrier roller, a layer roller, a web roller, an excess roller, a product roller, a separation drum and a screen drum to deliver materials associated with the said rollers and drums at a pre-set speed to at least two synchronised and aligned cutters, the rollers, drums and cutters performing the sequential steps of:10 drawing a non-stick carrier film from the carrier roller and a double-sided adhesive laminate having a protective layer 43 from the adhesive roller; fixing the carrier film to the laminate to cover substantial portion of the width of the film by drawing the film and laminate through compressing rollers to form a base substrate; passing the base substrate beneath a detachment tensioner to remove the protective layer by winding the protective layer onto the layer roller to produce an adhesive substrate having an exposed adhesive section; applying a silicone based non-stick web to the adhesive portion of the adhesive substrate by drawing the non-stick web from the web roller and passing the web and adhesive substrate between a plurality of compressing rollers to form a work substrate; removing selected portions of the work substrate using the a plurality of cutters disposed on and about an exterior surface of the precision substratecutting drum to form a perforated substrate; removing the carrier film from the perforated substrate to produce a connect substrate by drawing the film across a separation roller and around the separation drum; affixing a peelable screen to the connect substrate to form a rollable substrate by drawing the screen from the screen drum and is attaching the screen to a lower adhesive surface of the laminate; passing the rollable substrate through the shaping cutter to define a gasket outline shape and form a gasket outline substrate; removing material outside the gasket outline from the gasket outline substrate onto the excess roller; removing the protective coating from a plurality of adjacent gaskets using a 5 adhesive material; and applying a single continuous non-adhesive film across unprotected gaskets.

5. An apparatus for producing a gasket substantially as herein described with 10 reference to and as shown in the accompanying drawings.