CA1037875A - Elastomeric keyboard switch and its method of manufacture - Google Patents
Elastomeric keyboard switch and its method of manufactureInfo
- Publication number
- CA1037875A CA1037875A CA217,693A CA217693A CA1037875A CA 1037875 A CA1037875 A CA 1037875A CA 217693 A CA217693 A CA 217693A CA 1037875 A CA1037875 A CA 1037875A
- Authority
- CA
- Canada
- Prior art keywords
- keyboard
- electrically conductive
- conductive paint
- rubber
- paint
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D1/00—Processes for applying liquids or other fluent materials
- B05D1/32—Processes for applying liquids or other fluent materials using means for protecting parts of a surface not to be coated, e.g. using stencils, resists
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H13/00—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch
- H01H13/70—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch having a plurality of operating members associated with different sets of contacts, e.g. keyboard
- H01H13/702—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch having a plurality of operating members associated with different sets of contacts, e.g. keyboard with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H2229/00—Manufacturing
- H01H2229/002—Screen printing
- H01H2229/004—Conductive ink
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H2229/00—Manufacturing
- H01H2229/006—Pad transfer printing
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H2229/00—Manufacturing
- H01H2229/056—Laminating
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H2229/00—Manufacturing
- H01H2229/058—Curing or vulcanising of rubbers
Landscapes
- Push-Button Switches (AREA)
- Manufacture Of Switches (AREA)
- Input From Keyboards Or The Like (AREA)
Abstract
ABSTRACT OF DISCLOSURE
A method for manufacturing a keyboard which can be utilized in a keying structure is described. It consists of layering a flat fixed plate with a conductive paint, masking a preformed insulating rubber keyboard, laying the keyboard on the conductive paint surface and thereafter applying pressure to the rubber keyboard to the extent that certain portions of the rubber keyboard are put in contact with the conductive paint.
A method for manufacturing a keyboard which can be utilized in a keying structure is described. It consists of layering a flat fixed plate with a conductive paint, masking a preformed insulating rubber keyboard, laying the keyboard on the conductive paint surface and thereafter applying pressure to the rubber keyboard to the extent that certain portions of the rubber keyboard are put in contact with the conductive paint.
Description
1037~5 Rubber keyboards for keyed structures are not new.
Neither are rubber keyboards having electrically conductive portions thereon. There are problems, however, associated with the currently used keyboards as well as problems associated with their production.
Prior art keyboards are manufactured by joining a contact material, i.e., an electrically conductive material which has been fashioned beforehand, with a keyboard which is either made of non-conductive material or is coated with non-conductive material.
In a particular method, a large number of small contact members are press formed by molding in metal molds.
The contact members are thereafter affixed to the keyboard, thus constituting a two-step method of manufacture which is not only complicated but is time consuming. In order to `-- overcome the difficulties attendant in such an operation, this invention was conceived and reduced to practice.
This invention relates to a method of manufacturing a keyboard which is useful in keying structures. More particularly, this invention relates to a rubber keyboard which is useful in keying structures such as miniature, hand-held computers and calculators.
The method of this invention comprises layering a flat fixed plate with a thin layer of electrically conductive paint, masking a prefotmed insulating rubber keyboard, laying the so masked keyboard on the conductive paint and applying - pressure to the rubber keyboard to the extent that certain portions of the rubber keyboard are pressed downwardly into ,. , contact with the electrically conductive paint.
~` '`', , 1037~75 ~ i This invention also relates to an article of manufacture which is produced by the method of this invention.
More particularly, this invention relates to an insulating rubber keyboard which has certain designated areas upon its planar surface which are coated with an electrically conductive paint. ~ ~
Thus, in accordance with the present teachings, - ; -a method of manufacturing a keyboard is provided wherein the method comprises contacting a preformed rubber keyboard without - -electrically conductive paint at specific locations on the ~
keyboard to form the conductive contact. The method includes the steps of spreading a thin layer of electrically conductive paint on a flat fixed plate, surmounting the electrically conductive paint with a masking shield, surmounting the masking shield with a preformed insulating rubber keyboard, contacting the preformed insulated rubber keyboard with a pressure means - -whereupon those portions of the preformed rubber keyboard .7. .'1' which are not masked are forced downwardly into intimate contact with the electrically conductive paint causing the paint to adhere to the preformed rubber keyboard. The pressure means is subsequently released and the electrically conductive paint permitted to dry. '^
Pursuant to the above and other aspects, the invention will now be described in greater detail.
In the drawings, FIG. 1 is a plan view of the under portion of the finished keyboard showing the contact :
points 2A and the silicone rubber support material 4;
FIG. lA is a cross-sectional view of the key-board taken along the plane A-A; ;
FIG. 2 is a top plan view of the masking shield -3 with the requisite openings 7 through which the portion of rubber 4A passes to reach the electrically conductive paint;
,. .
FIGS. 3 and 4 show a cross-sectional view of the keyboard taken along the plane A-A shown in FIG. 1 and the apparatus used in manufacture during the various steps of the manufacture;
FIG. 5 is a cross-sectional view along plane A-A
of the finished article showing the rubber support material 4 and the contact thereupon, 2A.
Referring now to the drawings wherein like reference characters designate like or corresponding parts throughout the figures thereof, there is shown in FIG. 3 a cross-sectional view of a portion of the manufacturing apparatus and article of this invention. The invention requires a flat fixed plate 1 which is at least as wide as the width of the rubber keyboard w}lich is to be manufactured. Layered on the surface of the flat fixed plate is an electrically -~
- conductive paint Z. Shown above the components 1 and 2 are components 3 and 4, which are shown in plan view in FIGS. Z
and 1, respectively. The component 3 is a masking shield which protects the surfaces of the insulating rubber keyboard 4 which are not to be coated with the electrically conductive paint 2. The masking shield 3 is generally affixed to the rubber keyboard before the whole is surmounted on the electrically conductive paint surface, although the affixing of the masking shield is not essential and the masking shield can be placed directly on the paint surface and the rubber keyboard thereafter placed thereon. The rubber keyboard 4 is preformed from a resilient material, which resilience is necessary for the satisfactory operation of the finished part as well as for the satisfactory operation of the instant method. Note that the manufacture of the preformed rubber -3- ~
.`
'" ~ ' ~ ' ' ' !'; ' : . , '~., 10378'75 keyboard itself is not part of this invention. Note also :
that the rubber keyboard is manufactured with small rubber dimples 5 on its upper surface. These dimples correspond directly with the rubber portion 4A which is to become -the contact 2A.
Referring now to FIG. 4, there is shown a cross- -. i. .
sectional view of the same portion of apparatus as is shown in FIG. 3. The components 1, 2, 3 and 4 are in the proper position for the application of pressure. The pressure is supplied by a roller 6 which passes over the components 1 ~ -~
through 4 and causes the portions 4A to be pushed downwardly into the conductive paint surface. Note that the rubber dimples 5 enhance the pressure of the roller at that point -thereby causing the portions 4A to reach the paint surface without undue pressure on the remainder of the rubber keyboard `
that is not intended to be coated. Note also that the invention is not restricted to that portion of the invention where the roller is passed over the components 1 through 4. Contemplated within the scope of the invention is the situation where the components 1 through 4 are passed under a stationary roller, and mass production can be accomplished under such conditions by -providing the components in the form of a moving belt which is later cut into segments.
Immediately after the passage of the roller, the resilient rubber keyboakd, portion 4A, springs back to its normal configuration and the portion 4A is now coated with ~-the electrically conductive paint. The finished keyboard is then set aside to dry or cure, as the case may be, to form the contact 2A.
:~ 4_ . ~.
.
: .. . . - . . - ~ .: .
.
.:,.. . - - . . .i ~ , . .. , "
10378~5 Note that the drawings show 3 or 4 dimples 5 or 3 or 4 portions 4A but this is just for convenience in drawing and illustrating the invention. The number of such dimples 5 and portions 4A are not intended to be restricted to any certain ~ --number but are intended to be limited by practicality and need.
As mentioned supra, the insulating rubber keyboard 4 is preformed and the process and article thereby are not intended to be encompassed by this invention. The rubber keyboard can be any resilient rubber material which has electrical insulating properties. Preferred for this invention are curable silicone rubbers. Silicone rubbers are well known in the art and are well known to be electrically insulative. For those unfamiliar with such silicone rubbers, attention is directed to U.S. Patents Nos. 2,823,218; 3,159,601; 3,188,299 and 3,192,181. Also known are silicone rubbers that cure by the action of peroxide catalysis on unsaturated groups on silicon.
The electrically conductive paint can be a commercial paint containing a resin, pigments, conductive particles and ~ solvents or the electrically conductive paint can be a rubber 20 dispersion in water or solvent, said dispersion also containing pigments and/or conductive particles.
Preferred for this invention are silicone rubber dispersions containing electrically conductive particles or pigments. The amount of electrically conductive paint that is layered on the flat fixbd plate 1 can vary according to the desired end use of the finished product. For most uses, i however, the layer of electrically conductive paint on the surface of the fixed flat plate should be 1 to 2 mm. thick - in its uncured state. Depending upon the dilution of the base resin or rubber in the paint solution, this amount of `,.'" ~
. . : : . , . ........ .... . : . . . .... . ... -., .... ~
... ;-- . .. ~ . . . .. : .. : . . ..... - . . . ..
~037875 electrically conductive paint gives a contact point, when dried, of 0.5 to 2 mm. thick. Layers of electrically conductive paint which give in excess of 10 mm. in thickness are usually not practical for this invention. Furthermore, layers of ~ -electrically conductive paint which give less than 0.05 mm.
in thickness are also usually not practical for this invention. .
As noted earlier, the pressure necessary for the portion 4A to contact the wet electrically conductive paint is provided by way of a roller. Roller means are common in the art and no further elaboration is required. ;
While the invention has been particularly shown and described with reference to specific embodiments, it is to be understood by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention.
.
',', .
.':
''. ' .
-,
Neither are rubber keyboards having electrically conductive portions thereon. There are problems, however, associated with the currently used keyboards as well as problems associated with their production.
Prior art keyboards are manufactured by joining a contact material, i.e., an electrically conductive material which has been fashioned beforehand, with a keyboard which is either made of non-conductive material or is coated with non-conductive material.
In a particular method, a large number of small contact members are press formed by molding in metal molds.
The contact members are thereafter affixed to the keyboard, thus constituting a two-step method of manufacture which is not only complicated but is time consuming. In order to `-- overcome the difficulties attendant in such an operation, this invention was conceived and reduced to practice.
This invention relates to a method of manufacturing a keyboard which is useful in keying structures. More particularly, this invention relates to a rubber keyboard which is useful in keying structures such as miniature, hand-held computers and calculators.
The method of this invention comprises layering a flat fixed plate with a thin layer of electrically conductive paint, masking a prefotmed insulating rubber keyboard, laying the so masked keyboard on the conductive paint and applying - pressure to the rubber keyboard to the extent that certain portions of the rubber keyboard are pressed downwardly into ,. , contact with the electrically conductive paint.
~` '`', , 1037~75 ~ i This invention also relates to an article of manufacture which is produced by the method of this invention.
More particularly, this invention relates to an insulating rubber keyboard which has certain designated areas upon its planar surface which are coated with an electrically conductive paint. ~ ~
Thus, in accordance with the present teachings, - ; -a method of manufacturing a keyboard is provided wherein the method comprises contacting a preformed rubber keyboard without - -electrically conductive paint at specific locations on the ~
keyboard to form the conductive contact. The method includes the steps of spreading a thin layer of electrically conductive paint on a flat fixed plate, surmounting the electrically conductive paint with a masking shield, surmounting the masking shield with a preformed insulating rubber keyboard, contacting the preformed insulated rubber keyboard with a pressure means - -whereupon those portions of the preformed rubber keyboard .7. .'1' which are not masked are forced downwardly into intimate contact with the electrically conductive paint causing the paint to adhere to the preformed rubber keyboard. The pressure means is subsequently released and the electrically conductive paint permitted to dry. '^
Pursuant to the above and other aspects, the invention will now be described in greater detail.
In the drawings, FIG. 1 is a plan view of the under portion of the finished keyboard showing the contact :
points 2A and the silicone rubber support material 4;
FIG. lA is a cross-sectional view of the key-board taken along the plane A-A; ;
FIG. 2 is a top plan view of the masking shield -3 with the requisite openings 7 through which the portion of rubber 4A passes to reach the electrically conductive paint;
,. .
FIGS. 3 and 4 show a cross-sectional view of the keyboard taken along the plane A-A shown in FIG. 1 and the apparatus used in manufacture during the various steps of the manufacture;
FIG. 5 is a cross-sectional view along plane A-A
of the finished article showing the rubber support material 4 and the contact thereupon, 2A.
Referring now to the drawings wherein like reference characters designate like or corresponding parts throughout the figures thereof, there is shown in FIG. 3 a cross-sectional view of a portion of the manufacturing apparatus and article of this invention. The invention requires a flat fixed plate 1 which is at least as wide as the width of the rubber keyboard w}lich is to be manufactured. Layered on the surface of the flat fixed plate is an electrically -~
- conductive paint Z. Shown above the components 1 and 2 are components 3 and 4, which are shown in plan view in FIGS. Z
and 1, respectively. The component 3 is a masking shield which protects the surfaces of the insulating rubber keyboard 4 which are not to be coated with the electrically conductive paint 2. The masking shield 3 is generally affixed to the rubber keyboard before the whole is surmounted on the electrically conductive paint surface, although the affixing of the masking shield is not essential and the masking shield can be placed directly on the paint surface and the rubber keyboard thereafter placed thereon. The rubber keyboard 4 is preformed from a resilient material, which resilience is necessary for the satisfactory operation of the finished part as well as for the satisfactory operation of the instant method. Note that the manufacture of the preformed rubber -3- ~
.`
'" ~ ' ~ ' ' ' !'; ' : . , '~., 10378'75 keyboard itself is not part of this invention. Note also :
that the rubber keyboard is manufactured with small rubber dimples 5 on its upper surface. These dimples correspond directly with the rubber portion 4A which is to become -the contact 2A.
Referring now to FIG. 4, there is shown a cross- -. i. .
sectional view of the same portion of apparatus as is shown in FIG. 3. The components 1, 2, 3 and 4 are in the proper position for the application of pressure. The pressure is supplied by a roller 6 which passes over the components 1 ~ -~
through 4 and causes the portions 4A to be pushed downwardly into the conductive paint surface. Note that the rubber dimples 5 enhance the pressure of the roller at that point -thereby causing the portions 4A to reach the paint surface without undue pressure on the remainder of the rubber keyboard `
that is not intended to be coated. Note also that the invention is not restricted to that portion of the invention where the roller is passed over the components 1 through 4. Contemplated within the scope of the invention is the situation where the components 1 through 4 are passed under a stationary roller, and mass production can be accomplished under such conditions by -providing the components in the form of a moving belt which is later cut into segments.
Immediately after the passage of the roller, the resilient rubber keyboakd, portion 4A, springs back to its normal configuration and the portion 4A is now coated with ~-the electrically conductive paint. The finished keyboard is then set aside to dry or cure, as the case may be, to form the contact 2A.
:~ 4_ . ~.
.
: .. . . - . . - ~ .: .
.
.:,.. . - - . . .i ~ , . .. , "
10378~5 Note that the drawings show 3 or 4 dimples 5 or 3 or 4 portions 4A but this is just for convenience in drawing and illustrating the invention. The number of such dimples 5 and portions 4A are not intended to be restricted to any certain ~ --number but are intended to be limited by practicality and need.
As mentioned supra, the insulating rubber keyboard 4 is preformed and the process and article thereby are not intended to be encompassed by this invention. The rubber keyboard can be any resilient rubber material which has electrical insulating properties. Preferred for this invention are curable silicone rubbers. Silicone rubbers are well known in the art and are well known to be electrically insulative. For those unfamiliar with such silicone rubbers, attention is directed to U.S. Patents Nos. 2,823,218; 3,159,601; 3,188,299 and 3,192,181. Also known are silicone rubbers that cure by the action of peroxide catalysis on unsaturated groups on silicon.
The electrically conductive paint can be a commercial paint containing a resin, pigments, conductive particles and ~ solvents or the electrically conductive paint can be a rubber 20 dispersion in water or solvent, said dispersion also containing pigments and/or conductive particles.
Preferred for this invention are silicone rubber dispersions containing electrically conductive particles or pigments. The amount of electrically conductive paint that is layered on the flat fixbd plate 1 can vary according to the desired end use of the finished product. For most uses, i however, the layer of electrically conductive paint on the surface of the fixed flat plate should be 1 to 2 mm. thick - in its uncured state. Depending upon the dilution of the base resin or rubber in the paint solution, this amount of `,.'" ~
. . : : . , . ........ .... . : . . . .... . ... -., .... ~
... ;-- . .. ~ . . . .. : .. : . . ..... - . . . ..
~037875 electrically conductive paint gives a contact point, when dried, of 0.5 to 2 mm. thick. Layers of electrically conductive paint which give in excess of 10 mm. in thickness are usually not practical for this invention. Furthermore, layers of ~ -electrically conductive paint which give less than 0.05 mm.
in thickness are also usually not practical for this invention. .
As noted earlier, the pressure necessary for the portion 4A to contact the wet electrically conductive paint is provided by way of a roller. Roller means are common in the art and no further elaboration is required. ;
While the invention has been particularly shown and described with reference to specific embodiments, it is to be understood by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention.
.
',', .
.':
''. ' .
-,
Claims (5)
1. A method of manufacturing a keyboard which is useful in keying structures, the method comprises contacting a preformed rubber keyboard with electrically conductive paint, at specific locations on the keyboard, to form a conductive contact, the method characterized by spreading a thin layer of electrically conductive paint on a flat fixed plate;
surmounting the electrically conductive paint with a masking shield;
surmounting the masking shield with a preformed insulating rubber keyboard;
contacting the preformed insulating rubber keyboard with pressure means, whereupon those portions of the preformed rubber keyboard which are not masked are forced downwardly into intimate contact with the electrically conductive paint causing the paint to adhere to the preformed rubber keyboard, thereafter releasing the pressure means, and allowing the electrically conductive paint to dry.
surmounting the electrically conductive paint with a masking shield;
surmounting the masking shield with a preformed insulating rubber keyboard;
contacting the preformed insulating rubber keyboard with pressure means, whereupon those portions of the preformed rubber keyboard which are not masked are forced downwardly into intimate contact with the electrically conductive paint causing the paint to adhere to the preformed rubber keyboard, thereafter releasing the pressure means, and allowing the electrically conductive paint to dry.
2. The method of claim 1 wherein said pressure means is a pressure roller.
3. The method of claim 2 wherein the preformed insulating rubber keyboard consists of cured silicone rubber.
4. The method of claim 3 wherein the electrically conductive paint is a curable silicone paint.
5. The method of claim 3 wherein the electrically conductive paint is a curable silicone rubber dispersion containing electrically conductive particles.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP603874A JPS5647651B2 (en) | 1974-01-11 | 1974-01-11 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1037875A true CA1037875A (en) | 1978-09-05 |
Family
ID=11627463
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA217,693A Expired CA1037875A (en) | 1974-01-11 | 1975-01-10 | Elastomeric keyboard switch and its method of manufacture |
Country Status (10)
| Country | Link |
|---|---|
| JP (1) | JPS5647651B2 (en) |
| BE (1) | BE824289A (en) |
| CA (1) | CA1037875A (en) |
| CH (1) | CH596654A5 (en) |
| DE (1) | DE2500701C2 (en) |
| FR (1) | FR2257951B1 (en) |
| GB (1) | GB1493042A (en) |
| IT (1) | IT1048801B (en) |
| NL (1) | NL157740B (en) |
| SE (1) | SE404559B (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5486371U (en) * | 1977-11-30 | 1979-06-19 | ||
| DE3034585C2 (en) * | 1980-09-13 | 1982-11-04 | Philips Patentverwaltung Gmbh, 2000 Hamburg | Pushbutton arrangement in an electrical communications engineering device |
| DE3041186C2 (en) * | 1980-09-13 | 1984-03-29 | Philips Patentverwaltung Gmbh, 2000 Hamburg | Pushbutton arrangement in an electrical communications engineering device |
| DE3214454C2 (en) * | 1982-04-20 | 1984-08-23 | Rudolf Schadow Gmbh, 1000 Berlin | Electrical switch in foil construction |
| US4858174A (en) * | 1983-01-03 | 1989-08-15 | Pitney Bowes Inc. | Electronic postage meter control system employing a membrane switch mechanism |
| US4620075A (en) * | 1983-06-10 | 1986-10-28 | Price Pfister, Inc. | Unitized control panel |
| DE3415672A1 (en) * | 1984-04-27 | 1985-11-07 | Wilde Membran Impuls Tech | Multiple switch |
| DE3434107A1 (en) * | 1984-09-17 | 1986-03-20 | Siemens AG, 1000 Berlin und 8000 München | Switching mat for keyboards |
| DE3440979A1 (en) * | 1984-11-09 | 1986-05-15 | Marquardt Gmbh, 7201 Rietheim-Weilheim | ELECTRICAL COMPONENT LIKE KEYBOARD OR THE LIKE. |
| JPS61245417A (en) * | 1985-04-24 | 1986-10-31 | 富士ポリマテック株式会社 | Formation of contact rubber conducting section |
| DE3643124A1 (en) * | 1986-12-17 | 1988-07-07 | Ruf Kg Wilhelm | Keyboard |
| DE3714316A1 (en) * | 1987-04-29 | 1988-11-10 | Siemens Ag | Contact mat for keys and keyboards |
| JPH0298930U (en) * | 1989-01-25 | 1990-08-07 | ||
| CN112519086A (en) * | 2020-10-20 | 2021-03-19 | 北京中石伟业科技无锡有限公司 | Double-color conductive silica gel product forming process |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1298089A (en) * | 1969-02-24 | 1972-11-29 | William Barber Sudduth | Electric switch made of conducting elastomer |
| JPS5129921Y2 (en) * | 1971-03-24 | 1976-07-28 |
-
1974
- 1974-01-11 JP JP603874A patent/JPS5647651B2/ja not_active Expired
-
1975
- 1975-01-07 GB GB590/75A patent/GB1493042A/en not_active Expired
- 1975-01-08 SE SE7500165A patent/SE404559B/en unknown
- 1975-01-09 FR FR7500514A patent/FR2257951B1/fr not_active Expired
- 1975-01-09 DE DE2500701A patent/DE2500701C2/en not_active Expired
- 1975-01-10 IT IT19144/75A patent/IT1048801B/en active
- 1975-01-10 BE BE152295A patent/BE824289A/en unknown
- 1975-01-10 CH CH26075A patent/CH596654A5/xx not_active IP Right Cessation
- 1975-01-10 NL NL7500295.A patent/NL157740B/en not_active IP Right Cessation
- 1975-01-10 CA CA217,693A patent/CA1037875A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5647651B2 (en) | 1981-11-11 |
| FR2257951A1 (en) | 1975-08-08 |
| NL7500295A (en) | 1975-07-15 |
| DE2500701A1 (en) | 1975-07-17 |
| SE404559B (en) | 1978-10-09 |
| JPS50101868A (en) | 1975-08-12 |
| FR2257951B1 (en) | 1977-07-08 |
| NL157740B (en) | 1978-08-15 |
| GB1493042A (en) | 1977-11-23 |
| SE7500165L (en) | 1975-07-14 |
| BE824289A (en) | 1975-07-10 |
| AU7692774A (en) | 1976-07-01 |
| IT1048801B (en) | 1980-12-20 |
| DE2500701C2 (en) | 1985-10-03 |
| CH596654A5 (en) | 1978-03-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1037875A (en) | Elastomeric keyboard switch and its method of manufacture | |
| US4442055A (en) | Process for the manufacture of a contact mat | |
| US4067102A (en) | Methods of manufacturing tactile switch for keyboards and the like | |
| DE3366717D1 (en) | Process for producing a perforated foil for an electric dry-shaver with raised regions on the face contacting the skin | |
| US2963748A (en) | Printed circuits | |
| ATE88412T1 (en) | DEVICE FOR FORMING A PRESS BUTTON ''IN SITU'' ON A POROUS SUBSTRATE. | |
| US2988839A (en) | Process for making a printed circuit | |
| US3340606A (en) | Printed circuit structure and method of making the same | |
| US4143179A (en) | Method of manufacturing a keyboard | |
| GB2041828A (en) | A Method for Manufacturing Interconnectors | |
| JPS56123819A (en) | Shaping method for cover pad for sheet | |
| JPS57167659A (en) | Manufacture of semiconductor device | |
| JPS56117617A (en) | Frosting of synthetic resin molding | |
| JPS51131584A (en) | A process for manufacturing polyurethane rubber coated gloves | |
| JPS5574124A (en) | Manufacturing of insulated coil | |
| JPS62243214A (en) | Keyboard covering member | |
| JPS5586567A (en) | Preparation of decorative board | |
| JPS54142286A (en) | Production of rubber product | |
| JPS62163223A (en) | Key board | |
| JP3206298B2 (en) | Panel switch | |
| JPS57136116A (en) | Cord plate | |
| DK510481A (en) | PROCEDURE FOR MANUFACTURING AN ELECTRIC CONDUCTIVE PLASTIC MAT | |
| JPS6417340A (en) | Manufacture of touch switch | |
| JPS54157139A (en) | Method of forming the terminal surface of sprayed layer | |
| JPS57110423A (en) | Method for adhering thermoplastic synthetic resin sheet |