US3417215A - Electric switch - Google Patents

Description

Dec. 17, 1968 1-, CORONA ET AL 3,417,215

ELECTRIC SWITCH Filed June 22, 1966 3 Sheets-Sheet l sHonr LONG I38] Iii;

INVENTORS. THOMAS CORONA LEROY J. KELLY ATTORNEY-S.

T. CORONA ET AL ELECTRIC SWITCH Filed June 22, 1966 E .56 12g S we Q 552 127 6 use 72; 18 I04 Q 76 74 N 5 Sheets-Sheet 2 Q: /I/II/ 44 Q4 64 H8 :4 4e I22 I274 1 |20- 5M- 1I- I 6 V 72 Y 68 I28 Q 74 I00 80 53 I04 102 92 42 as 88 I06 86 no 82 I08 13:94

.l/VVENTORS. THOMAS CORONA LEROY a. KELLY ATTORNEYS.

Dec. 17, 1968 CORONA ET AL 3,417,215

ELECTRIC SWITCH 3 Sheets-Sheet :5

Filed June 22, 1966 5 w m m m 9 'l/VVENTORS. THOMAS CORONA LEROY J. KELLY BY .J &

ATTORNEYS.

United States Patent 3,417,215 ELECTRIC SWITCH Thomas Corona, Pleasantville, and Le Roy J. Kelly, Egg

Harbor Township, N.J., assignors of fifty percent to Thomas Corona, Pleasantville, and fifty percent to Le Roy J. Kelly, Egg Harbor Township, NJ.

Filed June 22, 1966, Ser. No. 559,551 Claims. (Cl. 200-86) This invention relates generally to electric switches and more particularly to a pneumatically controlled electric switch.

An annoying as well as time consuming situation is to arrive at home at night and not be able to determine in the dark which of the keys on a key ring is the proper key and having found the key, it is necessary to search for the key hole of the door lock. Various devices are available to overcome this difiiculty. One device is the pocket flashlight which is normally too bulky to carry in the pocket of a males clothing and is usually unavailable when needed. In addition to being bulky, flashlights require constant replacement of batteries as well as light bulbs.

A more suitable solution to lighten the area adjacent a door is the provision of a pressure sensitive mat which is electrically connected to enable energization of an outdoor lamp adjacent to the door. Prior systems, however, have proved inadequate since they are inflexible in that they cannot be turned off easily when lighting is not necessary. Further, the use of electrical contacts or other electrical components in mats outdoors is dangerous because the electrical components often become exposed through wear and therefore form an electrical hazard. Further, even though the components are well protected by the outer surface of the mat against children and adults putting their fingers or limbs in contact therewith, the mat may still not be waterproof. Therefore, on a rainy day, an electrical hazard is everpresent. Further, these mats have the disadvantage that unless someone is on the mat, the contacts are not urged against each other and therefore the light remains on only as long as the electric mat is stepped on. Thus, as soon as the user steps off of the mat, the light is turned off. This action does not provide a person with enough time to get indoors and find the indoor electrical switch. Further, a second person directly behind the first person may stumble in the dark until the first person is able to turn on the outdoor lamp for full time use. Finally, electrical contact type doormats are not coordinated with the conventional electric switch that is used for an outdoor lamp. Thus, two switches are required if control over the mat operation is desired. Two switches are thus necessary, one for normal operation and another for selection of the mat controlled operation of the lamp.

It is therefore an object of the invention to overcome the aforementioned disadvantages.

Another object of the invention is to provide a new and improved mat controlled electric switch which may be inhibited against operation when it is not necessary.

Another object of the invention is to provide a new and improved electric switch which uses a control mat having no electrical contactsv It is another object of the invention to provide a new and improved electric switch having a control mat which is impervious to the weather.

Another object of the invention is to provide a new and improved electric switch which may be used for both a normal lamp switching operation as well as being responsive to a control mat for operation of the lamp.

Another object of the invention is to provide a new and improved electric switch which is responsive to a control mat to operate a lamp for a predetermined length of time after a person has stepped off the mat.

These and other objects of the invention are achieved by providing in combination with a control mat comprisng an imperforate deformable envelope confining a cushlon of air, a pressure responsive electric switch, said switch comprising a manually movable member, a slidable member controlled by said mat, a pair of conductive strips and a pair of wipers, said switch enabling energization of an electrical load when a closed circuit is made between said conductive strips, one of said wipers being connected to one of said strips and the other of said wipers being mounted adjacent the other of said strips, said movable member having a first conductive member which is adapted to make a closed circuit between said strips when said movable member is in a first position and a second conductive member which is adapted to make a closed circuit between said other wiper and said other strip when said movable member is in a second position, said movable member adapted to be placed in a third position which prevents making a closed circuit between said strips, said slidable member having a head including a conductive surface so that said slidable member when activated by said mat makes a closed circuit between said wipers which in turn makes a closed circuit between said conductive strips when said movable memher is in its said second position.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a fragmentary perspective view of a house embodying the invention;

FIG. 2 is a sectional view of the control mat embodying the invention taken along the line 2-2 in FIG. 1;

FIG. 3 is a front elevational view of a wall plate used on the device embodying the invention;

FIG. 4 is an enlarged sectional view of the electric switch embodying the invention in the off position taken along the line 4-4 in FIG. 3;

FIG. 5 is an enlarged sectional view of the electric switch taken along the line 55 in FIG. 4;

FIG. 6 is an enlarged sectional view similar to FIG. 4 with the switch shown in an on position;

FIG. 7 is a sectional view taken along the line 77 in FIG. 6;

FIG. 8 is an enlarged sectional view similar to FIG. 4 with the electric switch shown in the delay position; and

FIG. 9 is a sectional view taken along the line 9-9 in FIG. 8.

Referring now in greater detail to the various figures of the drawings wherein similar reference characters refer to similar parts, an electric switch embodying the present invention is generally shown at 20 in FIG. 1.

Electric switch 20 is responsive to a pressure sensitive mat 22 which is connected to switch 20 by a tube 24. As best seen in FIG. 2, the mat 22 comprises a continuous envelope of an impervious material which may preferably be an elastomer or a synthetic such as a thermoplastic resin. The mat 22 is generally rectangular and comprises a rectangular planar top wall 26 and a rectangular planar bottom wall 28 which are integrally connected by an arcuate skirt 30 which extends peripherally about and between top wall 26 and bottom wall 28. The mat thus confines a cushion of air. It should be understood that a highly porous material or integral ribs may also be used inside the mat to provide additional resilient support for top wall 26. The mat is preferably decorative and thus may be used as a welcome mat.

Tube 24 is integrally connected to the mat 22 and communicates with an opening therein. It is, of course, understood that the tube may also be connected to an opening in the mat by a suitable fitting. Thus, pressure applied in the direction of arrow 32 deforms the top wall 26 and moves it as shown in phantom at 26.

When the mat is so deformed, air pressure is applied to tube 24 in the direction of arrow 34. The mat 22 is so constructed that when weight is taken off the top wall 26, the wall 26 resumes its former shape. The mat further includes a suitable one-way valve 35 in skirt 30 thereof. Valve 35 is provided to pass air only into the mat 26. Thus, no air escapes through valve 35 when pressure is applied to mat 32, however, when pressure is released from the top surface of wall 26 of the mat, valve 35 em ables the mat to resume its shape as air is taken in by the mat.

The electric switch 20 basically comprises a mounting bracket 36 which is preferably comprised of a resilient n'onconductive material, a pivotable selection member 38, a piston 40, and cylinder 42. As best seen in FIGS. 4 and 5, the mounting bracket 36 includes a first portion 44 which is generally rectangular and which houses the selection member 38. A pair of terminals 46 and 48 are provided on the opposite vertically extending side walls 50 and 52 of portion 44. The terminals 46 and 48 each include a longitudinally extending bore which is adapted to threadedly receive a fastener 54 and 56, respectively. Fasteners 54 and 56 are secured in the openings in terminals 46 and 48, respectively. The fasteners 54 and 56 secure to the terminals 46 and 48 leads 58 and 60, respectively, of a cable 62.

As best seen schematically in FIG. and hereinafter described, the cable 62 provides to the switch the voltage from a conventional household voltage source. A first conductive strip 64 is connected to and depends from terminal 46 along the inner surface of wall 50. A second conductive strip 66 is connected to and depends from terminal 48 along the inner surface of wall 52. Strips 64 and 66 are preferably integral with terminals 46 and 48, respectively, but may also be formed separately and secured thereto by soldering or other electrically conductive connection. A third conductive strip 68 is mounted to the inner surface of wall 50 spaced below but adjacent to the lowermost end of strip 64. Both strips 64 and 68 have at their ends closest to each other a projecting contact 70 and 72, respectively. The purpose of these contacts will hereinafter be seen.

A pair of terminals which are formed as wipers 74 and 76 depend from strips 66 and 68 beyond lower horizontal wall 78 of the rectangular portion 44 of the mounting bracket 36. Wipers 74 and 76 are arcuately shaped and are symmetrically spaced from each other with the centers thereof spaced closest to each other.

Referring again to FIG. 4, it can be seen that mounting bracket 36 further includes a lower portion 80 which depends from the horizontal wall 78 of the rectangular portion 44. The cylinder 42 is integral with the lower portion 80. The lower portion 80 of the mounting bracket 36 further includes a vertically depending integral member 82. Member 82 includes an opening which extends horizontally therethrough and into communication with the bore of cylinder 42. A threaded member 84 is threadedly secured in the horizontal opening of member 82 and includes a slotted end 86 which is adapted to receive a coin or screw driver for rotating it within the opening.

The threaded member 84 also includes a tapered end 88. The horizontal opening in member 82 includes a portion 90 which is of smaller cross-section than the portion of the opening in which the threaded portion of member 84 extends. The portion 90 of the opening is separated from the major portion of the opening by a vertically extending opening 92. The tapered portion 88 of threaded member 84 is adapted to be inserted into opening 90 by appropriate rotation of the threaded member 84. Thus, the size of the opening to the bore of cylinder 42 may be varied by rotation of threaded member 84. The opening 92 is adjacent the lower end of cylinder 42 and acts as an outlet for the air in the cylinder when the piston 40 is urged downwardly as will hereinafter be seen. The cylinder 42 also includes an opening 94 adjacent its uppermost end which acts as a port to release the air when piston 40 is moved upwardly.

The main body of the piston 40 is comprised of an elongated cylindrical shaft 96, a cylindrical end piece 98 at its lowermost end and an enlarged head 100 at its uppermost end. The enlarged head 100 includes a conductive surface 102 which is comprised of an annular metal band which is secured to the outer periphery of the enlarged head 100. The topmost portion 104 of head 100 is tapered to facilitate its insertion between the wipers 74 and 76 when the piston 40 is moved upwardly. The cylinder 42 includes a spring 106 which is axially mounted on shaft 96 of the piston 40 and extends from the top of a bore of the cylinder to the inner surface of cylindrical end piece 98. Thus, spring 106 normally urges the piston 40 downwardly. The cylinder 42 includes at the lowermost end of its bore an axially tapered portion 108 having an axially extending bore 110 which extends into the bore of said cylinder. As best seen in FIG. 4, the tube 24 is connected to the cylinder 42 about tapered portion 108. A ball 112 is provided within the cylinder adjacent bore 110 which in combination therewith acts as a ball valve for enabling air to be passed only in a direction from tube 24 into the bore of the cylinder and not in the reverse direction.

The shaft 96 of piston 40 extends through a vertical opening in the lower portion 80 of the mounting bracket 36 to the enlarged head 100 of the piston. The opening acts to restrain the piston against. transverse movement and enables the shaft to slide vertically therein. As best seen in FIG. 5, the head 100 is vertically aligned with the vertical axis of symmetry between wipers 74 and 76 so that when moved upwardly, the head urges the wipers 74 and 76 away from each other until the conductive surface 102 contacts the inner surface of both of these wipers. Thus, when moved upwardly, the head makes a closed electrical circuit between the wipers.

The pivotable selection member 38 includes a cylindrical portion 114 and three integral radially extending arms 116, 118, and 120. Arm 116 is adapted to extend out of the rectangular portion 44 of the mounting bracket 36 and is accessible for manual pivoting of the pivotable selection member 38. Arm 118 is perpendicular to arm 116 and includes a conductive clip 122 which extends transversely across arm 118 so that a portion thereof is exposed on each of the lateral surfaces of the arm 118. Arm 120 extends diametrically opposite to arm 118 and perpendicular to arm 116 and includes a conductive contact 124 which is secured to the lateral surface of arm 120 facing wall 50 of portion 44 of the mounting bracket 36.

The conductive clip 122 is adapted to abut terminals 46 and 48 when it is aligned therewith, thus, forming a closed circuit between strips 64 and 66. Clip 122 is aligned with the terminals 46 and 48 when the arm 116 is pivoted to its uppermost position as shown in FIG. 6. The contact 124 is adapted to make a closed circuit between strips 64 and 68 by contacting both contacts 70 and 72 thereof when arm 116 is disposed in the central or horizontal position as shown in FIGS. 8 and 9.

The selection member 38 further includes a pair of bosses 125 which are integral with, are axially aligned with and are disposed on opposite sides of the cylindrical portion 114 thereof. The selection member 38 is pivotably mounted in the rectangular portion 44 of the mounting bracket 36 about shaft 127 which extends through an opening in each of the side walls 50 and 52 of the mounting bracket 36 and through the bosses 125 and the cylindrical portion 114 of the switch. Bosses 125 act to space and center the selection member 38 between the side walls 50 and 52 of the mounting bracket 36. Therefore, the selection member 38 is pivotable about the shaft 127 which is preferably secured thereto by a pressed fit.

As seen in FIG. 4, a rectangular switch plate 126 is secured to the mounting bracket 36 by a pair of threaded fasteners 128 which extend through openings in the plate and are threadedly secured in openings in the mounting bracket 36 which are aligned with the openings in the plate.

As best seen in FIG. 3, the switch plate 126 is substantially planar and includes an elongated rectangular slot 130 through which arm 116 extends. The switch plate 126 includes adjacent the slot 130 the markings on, delay and off which indicate the position in which the arm 116 is disposed in order to perform the on, delay or off function. With the arm 116 in the position shown adjacent the legend off, as in FIG. 3, and the position shown in FIGS. 4 and 5, it can be seen that the conductive clip 122 and conductive contact 124 on arms 118 and 120, respectively, are not aligned with or in contact with either the terminals 46 and 48 or contacts 70 and 72, respectively. Therefore, a completed circuit cannot be made between leads 58 and 60.

As seen in FIG. 5, terminal 48 is connected via lead 60 to a first input terminal 132 and terminal 46 is connected via lead 58 and a lamp 134 to another input terminal 136. Terminals 132 and 136 are connected to a voltage source. The source of voltage is suitably a conventional household voltage. Thus, in order to provide current to lamp 134 to energize the same, it is necessary to complete the circuit between terminals 46 and 48 which provides a closed circuit between leads 58 and 60.

Referring noW to FIGS. 6 and 7, it can be seen that when the arm 116 of the selection member 38 is in the uppermost position adjacent the on legend, the arm 118 is disposed adjacent terminals 46 and 48. Thus, conductive clip 122 contacts both terminals 46 and 48 thereby causing a closed circuit between leads 58 and 60 which results in energization of lamp 134. In this position, the lamp 134 stays on irrespective of whether or not someone steps on mat 22. Similarly, in the prior position, when the arm is in the off position, the lamp 134 remains deenergized irrespective of whether or not anyone steps on the control mat 22.

The mat 22 controls the energization of lamp 134 only when arm 116 is in the horizontal position adjacent the legend delay as shown in FIGS. 8 and 9. In the delay position, it can be seen that arm 120 is positioned adjacent strips 64 and 68 so that the contact 124 abuts the contacts 70 and 72 of strips 64 and 68, respectively, and thereby forms a closed circuit therebetween. As hereinbefore mentioned, when a closed circuit is formed between strips 64 and 66, the lamp 134 is energized by the voltage source at terminals 132 and 136. Thus, by electrically connecting wipers 74 and 76 when contact 124 connects strips 64 and 68, a closed circuit is formed between strips 64 and 66.

In FIGS. 8 and 9, the enlarged head 100 of piston 40 is shown both in full line and in phantom. As shown in full line at 100, the head is in its lowermost position and not placed between wipers 74 and 76. Therefore, conductive surface 102 is not in contact with wipers 74 and 76 leaving an open circuit therebetween and the lamp 134 is not energized. If, however, someone steps on mat 22, air pressure will be applied via tube 24 to piston 40 which thereby pushes the head to the position shown in phantom at 100' in FIGS. 8 and 9. In this position, surface 102 makes a complete circuit between wipers 74 and 76 and thereby completes a circuit through lamp 134, thus, energizing the lamp. When the person steps 01? the mat 22, the air pressure in tube 24 is released. The spring 106 urges the piston 40 downwardly. The only escape, however, for air in the bore of the cylinder is through opening 90 and opening 92. The bore 110 is not accessible to the release of air in that ball 112 is urged against the inlet thereto. The amount of opening between openings 90 and 92 is determined by the lentgh of threaded member 84 which is inserted into opening 90. Thus, by limiting the passage between openings 90 and 92, the lowering of piston 40 can be somewhat delayed. Therefore, the lamp 134 remains on for a predetermined period of time after someone has stepped off the mat. Valve 35 of mat 22 enables the mat to resume its shape by enabling the mat to take air in therethrough.

The amount of time that the lamp stays on can be varied by the loosening or tightening of the threaded member 84. An opening 138 is provided in switch plate 126 adjacent the bottom thereof so that access may be had from the outside of switch plate 126 to threaded member 84. As shown in FIG. 3, the legends short and long in addition to arrow 140 are placed on the outside surface of plate 126 adjacent opening 138 so that adjustment made to lengthen or shorten the amount of time which the lamp stays on after the mat has been stepped off may be facilitated.

The entire switch 20 is adapted to be mounted in a conventional rectangular terminal box 142. Mounting bracket 36 is pressed into the terminal box 142 and is secured therein by the natural resiliency of the material comprising the bracket. -It is necessary only to provide an opening 144 in the bottom wall 146 of the terminal box 142 to accommodate the cylinder 42 and vertical member 82. The inclined surface of lower portion of the mounting bracket facilitates the insertion of the mounting bracket into the terminal box 142.

Thus, the switch is suitable for replacing a presently existing conventional switch which merely operates a lamp in the normal on-oif mode. The switch is also convenient for placement in a new home in that conventional equipment such as terminal boxes may be used and specially designed boxes are not required therefor. The mat 22 is placed outside the door, and the tube 24 is run to the switch 20 which is normally mounted on the inside wall of a house adjacent the door. A lamp placed ouside the door may then be controlled by the mat.

The electric switch is adapted, in addition to being controlled by the mat, to perform the conventional function of operating a lamp 134 in the on-off mode. Thus, only one switch is necessary and it is simple to understand and to use. If a person leaves his home and does not expect to return until late at night, he merely sets the arm 116 adjacent the legend delay and the lamp 134 lights the outside area of the door when someone steps on control mat 22. The light need not therefore be energized when not in use. In addition, if an unsuspecting burglar should step on the mat, the energization of the lamp can frighten the burglar off.

Because the switch is pneumatically operated, there are no electrical contacts in the mat 22. Thus, the entire mat 22 can be constructed of a material impervious to the elements. Also, there is no danger of the mat wearing and therefore exposing an electrical contact which is an electrical shock hazard.

Without further elaboration, the foregoing will so fully illustrate our invention, that others may, by applying current or future knowledge, readily adapt the same for use under various conditions of service.

What is claimed as the invention is:

1. In combination with a control mat comprising an imperforate deformable envelope confining a cushion of air, a pressure responsive electric switch, said switch comprising a manually movable member, a slidable member controlled by said mat, a pair of conductive strips and a pair of wipers, said switch enabling energization of an electrical load when a closed circuit is made between said conductive strips, one of said wipers being connected to one of said strips and the other of said wipers being mounted adjacent the other of said strips, said movable member having a first conductive member which is adapted to make a closed circuit between said strips when said movable member is in a first position and a second conductive member which is adapted to make a closed circuit between said other wiper and said other strip when said movable member is in a second position, said movable member adapted to be placed in a third position which prevents making a closed circuit between said strips, said slidable member having a head including a conductive surface so that said slidable member when activated by said mat makes a closed circuit between said wipers which in turn makes a closed circuit between said conductive strips when said movable member is in its said second position.

2. The combination of claim 1 wherein said slidable member is comprised of a piston which is longitudinally slidable in a cylinder, said cylinder including a means for limiting the flow of air out of said cylinder so that said electrical load is energized for a period after said member is activated by said mat.

3. The combination of claim 1 wherein said electrical load comprises a lamp and said mat is placed adjacent the outside of a door so that pressure applied to said mat enables said lamp to light the area outside said door.

4. The combination of claim 1 wherein said manually movable member comprises a cylindrical body portion having a first arm which extends radially and is accessible for manual pivoting of said member, a second arm which carries said first conductive member, said first conductive member extending transversely of said arm and a third arm which carries said second conductive member on a lateral surface thereof.

5. The combination of claim 1 wherein said pressure responsive electric switch is adapted to be housed in a conventional terminal box so that replacement of a conventional switch with said pressure responsiv switch is facilitated.

6. The combination of claim 1 wherein said mat is comprised of an elastomeric material and includes only non-electrically conductive components.

7. The combination of claim 2 wherein said mat includes a one-way valve for passing air into said mat so that said mat may resume its normal shape after being stepped off.

8. An electric switching system for controlling the energization of an outdoor lamp adjacent the door of a dwelling, said system comprising a control mat and an electric switch responsive thereto, said control mat comprising an imperforate envelope which normally holds the shape of a rectangular doormat, said mat being connected to said switch via an elongated tube, said mat providing air pressure to said switch through said tube when said mat is stepped on and thereby deformed, said switc'h including a normally open circuit, said air pressure adapted to close said circuit, said switch further including means for maintaining said pressure to keep said circuit closed a predetermined period of time after said mat is stepped-01f, said switch having a manually operable member to enable operation of said switch in three selectable modes, when said member is in a first position, said switch is operable to continuously energize said lamp when said member is in a second position, said switch controls energization of said lamp in accordance with pressure applied to said control mat so that when the mat is stepped on, said lamp is energized through said circuit as long as it is closed when said member is in its third position, said switch continuously prevents energization of said lamp irrespective of said control mat whereby said switch enables said lamp to be operated in both a conventional on-oflf manner as well as to be controlled by said control mat.

9. The combination of claim 8 wherein said switch includes means for adjusting the amount of time said lamp remains energized after the mat is stepped oif when said switch member in said second position.

10. The combination of claim 8 wherein said electric switch is removably mounted in a terminal box.

References Cited UNITED STATES PATENTS 285,334 9/1883 Wiswall 200-86 2,215,788 9/1940 Hamilton et al. 200-33 2,251,180 7/1941 Wesley et al. 200-86 2,371,526 3/ 1945 Knipp ZOO-86 2,795,668 6/1957 Puckett 20086 2,841,665 7/1958 Smith 200-33 3,185,782 5/1965 Lakin 200-33 BERNARD A. GILHEANY, Primary Examiner.

F. E. BELL, Assistant Examiner.

Claims (1)

1. IN COMBINATION WITH A CONTROL MAT COMPRISING AN IMPERFORATE DEFORMABLE ENVELOPE CONFINING A CUSHION OF AIR, A PRESSURE RESPONSIVE ELECTRIC SWITCH, SAID SWITCH COMPRISING A MANUALLY MOVABLE MEMBER, A SLIDABLE MEMBER CONTROLLED BY SAID MAT, A PAIR OF CONDUCTIVE STRIPS AND A PAIR OF WIPERS, SAID SWITCH ENABLING ENERGIZATION OF AN ELECTRICAL LOAD WHEN A CLOSED CIRCUIT IS MADE BETWEEN SAID CONDUCTIVE STRIPS, ONE OF SAID WIPERS BEING CONNECTED TO ONE OF SAID STRIPS AND THE OTHER OF SAID WIPERS BEING MOUNTED ADJACENT THE OTHER OF SAID STRIPS, SAID MOVABLE MEMBER HAVING A FIRST CONDUCTIVE MEMBER WHICH IS ADAPTED TO MAKE A CLOSED CIRCUIT BETWEEN SAID STRIPS WHEN SAID MOVABLE MEMBER IS IN A FIRST POSITION AND A SECOND CONDUCTIVE MEMBER WHICH IS ADAPTED TO MAKE A CLOSED CIRCUIT BETWEEN SAID OTHER WIPER AND SAID OTHER STRIP WHEN SAID MOVABLE MEMBER IS IN A SECOND POSITION, SAID MOVABLE MEMBER ADAPTED TO BE PLACED IN A THIRD POSITION WHICH PREVENTS MAKING A CLOSED CIRCUIT BETWEEN SAID STRIPS, SAID SLIDABLE MEMBER HAVING A HEAD INCLUDING A CONDUCTIVE SURFACE SO THAT SAID SLIDABLE MEMBER WHEN ACTIVATED BY

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