CA2263007A1 - Safety edge for an electrically operated door - Google Patents

Abstract

A safety edge for an electrically operated door includes a female housing strip, a male actuator strip and means for attaching the safety edge to an edge of the door. The female housing strip has an interior cavity in which is positioned a first electrical contact. The male actuator strip has a second electrical contact.
The male actuator strip is telescopically received in the female housing strip. The male actuator strip is movable between a first position in which the second electrical contact is spaced from the first electrical contact and a second position in which the second electrical contact engages the first electrical contact to complete a normally open circuit.

Description

SAFETY EDGE FOR AN ELECTRICALLY OPERATED DOOR
FIELD OF THE INVENTION
The present invention relates to a safety edge for connection to a surface such as an electrically operated door.
BACKGROUND OF THE INVENTION
Electrically operated doors, especially overhead doors, are inherently dangerous. During their downward travel mode, overhead doors are capable of trapping and exerting extreme force upon any object obstructing their path of travel.
Therefore, a triggering device is placed upon the lower lead edge of the door which serves to reverse the direction of travel of the overhead door should an object obstruct the door's path of travel. These triggering devices are known as safety edges, although they are also referred to as reversing systems or reversing bars.
One common type of safety edge is a pneumatic system. A gum-hose is used to force air to a diaphragm operated switch. The diaphragm, when aroused by the force of said air, touches a set of electrical points together. Pneumatic systems have a number of inherent problems. The diaphragm operated switch is hidden from view and is, therefore, difficult to inspect for routine maintenance. The gum-hose has a tendency to crack, rot and leak; thereby rendering the system ineffective.
Should the door encounter a narrow obstruction during downward travel, a pneumatic reversing system does not always transmit sufficient air through said gum-hose to operate the diaphragm switch. The longer the hose used (i.e. for larger or wider doors), the less effective pneumatic systems become, due to outward deflection of the longer gum-hose, reducing airflow to said diaphragm. This is especially evident when the gum-hose is compressed furthest from said diaphragm switch. On very slow moving doors, the operating capabilities of this switch are extremely limited, due to a reduced force of airflow to said diaphragm.
A more reliable and widely used system is the mechanical safety edge system. Mechanical safety edge systems consist of a metal rail attached to the lead edge of a door section by a hinged attachment system. The mechanical safety edge relies upon gravity to disengage one or more electric switches fastened to the inner face of a bottom section of door. The metal rail pivots upwardly about its hinges upon striking an object in its path of travel. The switches are positioned to be struck by the metal rail or its linkages as it pivots. Although mechanical systems are far more reliable than pneumatic systems, they also have inherent drawbacks. The weight of the metal rail makes it difficult to attach to new lightweight doors and also causes counterbalancing problems. T'he linkages tend to wear or come out of alignment with the switches they are supposed to contact, thus causing the safety edge to malfunction.
A third style of safety edge is the compressible electrical contact system.
This system consists of thin ribbons of copper tape, separated by foam rubber strips.
The foam rubber strips are uniformly perforated, and when compressed allow the ribbons of copper tape to contact, sending an electrical signal. As with the other systems described above, this system has inherent defects. The system is housed in a canvas and/or rubber sheath. If the sheath becomes torn, cracked or perforated, the incursion of moisture creates a short in the electrical system. This type of reversing bar is also extremely expensive, and has to be manufactured to suit the length of each individual door size on which it is to be used. This presents stocking problems, as well as marketing concerns. For these reasons the compressible electrical contact system is not as widely used a system as either the pneumatic or mechanical safety edges.
A fourth style of safety edge is similar to both the pneumatic and compressible electrical contact systems described above, and consists of a deformable member positioned along the bottom edge of the door. The deformable member carries an electrical contact which engages a second electrical contact mounted on the bottom of the door when the door encounters an obstruction and the deformable member is deformed. One disadvantage of this system is that the deformable member, which is often made from plastic or rubber, is prone to cracking, rotting and leaking (as in the pneumatic system), with the result first, that the deformable member may cease to function properly and second, that the electrical contacts may become exposed to dirt and moisture and thus become fouled. A second disadvantage of this system is that the size and configuration of the deformable member is limited by the requirement that it must provide for the electrical contacts to be separated when the deformable member is not deformed and also provide for the electrical contacts to be engaged when the deformable member is deformed. This disadvantage is particularly significant in circumstances where the deformable member also serves to provide a seal between the door and the floor when the door is closed.
SUMMARY OF THE INVENTION
What is required is an alternative safety edge that obviates some or all of the problems present in the prior art.
According to the present invention there is provided a safety edge which includes a female housing strip and a male actuator strip. The female housing strip has an interior cavity in which is positioned at least one of a first electrical contact means.
The male actuator strip has at least one of a second electrical contact means.
The male actuator strip is telescopically received in the female housing strip. In a preferred embodiment of the invention, the male actuator strip is telescopically received in the interior cavity of the female housing strip. The male actuator strip is movable between a first position in which the second electrical contact means is spaced from the first electrical contact means and a second position in which the second electrical contact means engages the first electrical contact means to close or complete a normally open circuit.
Means is provided for attaching the safety edge to a surface. In the preferred embodiment of the invention, means are provided for attaching the female housing strip to the surface. Alternatively, the male actuator strip may be attached to the surface. The surface may be the edge of a door, window, shutter, wall, gate, panel or any other surface which may cause injury or damage if it is permitted to move without regard to obstructions that may be in its path. In the preferred embodiment, the safety edge is intended to be used in conjunction with an automatically closing door.
The means for attaching the safety edge to the door may be integral with the safety edge or may be comprised of a separate component or components.
Where the means for attaching the safety edge to the door are integral with the safety edge, the means may be comprised of an integral attachment flange which extends from and is formed as part of either the female housing strip or the male actuator strip.
Where the means for attaching the safety edge to the door is comprised of a component or components separate from the safety edge, the means may be comprised of a separate attachment flange which can be mounted on the edge of a door or other surface and can also be attached to either the female housing strip or the male actuator strip. Preferably, the separate attachment flange and the female housing strip comprise an attachment lug and a complementary attachment groove to facilitate attachment of the separate attachment flange to the female housing strip. In a preferred embodiment, the separate attachment flange comprises the attachment lug and the female housing strip comprises the attachment groove.
The separate attachment flange may be of any shape and size as long as it facilitates attachment of the safety edge to the edge of the door or other surface.
Preferably, the female housing strip is compatible with a variety of shapes and sizes of separate attachment flange in order to maximize the versatility of the safety edge.
Preferably the safety edge includes both an integral attachment flange and a separate attachment flange and preferably the integral attachment flange can be severed from the safety edge if its use is not required.
In the preferred embodiment, each female housing strip and male actuator strip together comprise a safety edge unit, and a plurality of safety edge units are connected together to form a complete safety edge. In this embodiment, the safety edge further comprises a connector comprising at least one connective member for connecting adjacent safety edge units together both structurally and electrically. More particularly, in the preferred embodiment, each female housing strip of the plurality of safety edge units has opposed ends, adjacent female housing strips have adjacent opposed ends, and the connector connects the adjacent opposed ends of the adjacent female housing strips.
Each female housing strip may have an interior wall, an exterior wall and a plurality of channels disposed between the interior wall and the exterior wall, and the connector may comprise at least one connective member insertable into at least one of the plurality of channels at the adjacent opposed ends of the adjacent female housing strips. Preferably the channels extend between the opposed ends of the female housing strip and preferably the connector comprises at least one connective member for connecting the safety edge units together structurally and comprises at least one connective member for connecting the safety edge units together electrically.
The structural connective member may be comprised of any shape or size which is compatible with the corresponding channels in the female housing strips to provide a firm connection between adjacent female housing strips while permitting limited flexure of the joint between adjacent female housing strips. In a preferred embodiment, the structural connective member is comprised of two pairs of tines, with each pair of tines being insertable in a channel of a female housing strip for engagement with a locking pin which extends across the channel.
The first electrical contact means may extend the full length of the female housing strip or may be positioned intermittently along the female housing strip.
Preferably, however, the first electrical contact means preferably comprises a pair of first electrical contacts. Preferably, one of the pair of first electrical contacts is positioned at one of the opposed ends of the female housing strip and another of the pair of first electrical contacts is positioned at another of the opposed ends of the female housing strip, and preferably the pair of first electrical contacts is electrically connected by using conductive material such as wiring, metal strips or by other means known in the art.
The first electrical contact means may comprise a positive electrical contact and a negative electrical contact in spaced relation, and the second electrical contact means may comprise a bridge contact so that when the male actuator strip is in the second position the bridge contact spans between the positive electrical contact and the negative electrical contact to close the normally open circuit. The second electrical contact means may extend the full length of the male actuator strip or it may be positioned intermittently along the male actuator strip as long as the second electrical contact means can engage the first electrical contact means when the male actuator strip is in the second position.

Preferably, one or both of the first electrical contact means and the second electrical contact means is pivotable so that an electrical connection can be made between the first and second electrical contact means when the male actuator strip is in the second position even when the male actuator strip does not telescope evenly along the length of the female housing strip. Most preferably, the second electrical contact means are pivotable relative to the male actuator strip. In a preferred embodiment, the second electrical contact means are mounted on the male actuator strip such that they "float" relative to the male actuator strip. The second electrical contact means preferably "float" relative to the male actuator strip as a result of being connected to the male actuator strip with a biasing device, which in the preferred embodiment is either a spring or an elastomeric material. The biasing device may be located in a cavity defined by the male actuator strip.
In the preferred embodiment, the female housing strip is a "C" channel in cross section and the male actuator strip is telescopically received within the "C"
channel. The safety edge may also comprise a stop means to prevent the male actuator strip from being withdrawn from the female housing strip. In the preferred embodiment, the stop means comprises internal shoulders in the interior cavity of the female housing strip which are adapted to engage external shoulders on the male actuator strip when the second electrical contact means is spaced from the first electrical contact means by a predetermined distance. Other forms of stop means may, however, be utilized in the invention.
The safety edge may also comprise biasing means to bias the male actuator strip toward the first position. In the preferred embodiment, the biasing means comprise springs such as coil springs or leaf springs which are positioned between the male actuator strip and the female housing strip in the interior cavity of the female housing strip. In the preferred embodiment where coil springs are used, the coil springs are received in pockets located on the male actuator strip. Other forms of biasing means may, however, be used in the invention as long as they provide the specified biasing function. Such alternative biasing means may include other types of springs or other resilient material such as foam rubber or may even comprise a form of pneumatic or hydraulic dampening system.

The safety edge units of the present invention may be fabricated in any length and may then be cut and assembled to create a safety edge as required for a specific application. As a result, the various components of the safety edge are preferably designed to be easily assembled in the field so that manufacturing of the components can be standardized.
In particular, preferably the structural and electrical connective members may be inserted and removed from the channels of the female housing strip without causing damage to any components of the safety edge. In addition, preferably removable endblocks are provided at both ends of each safety edge unit. These removable endblocks add strength to the safety edge and assist in maintaining the orientation of the male actuator strip in the female housing strip. They also provide a conduit for conductive material such as wiring which pass through the female housing strip and the endblocks.
The removable endblocks preferably fit snugly in the ends of the female housing strips and accommodate the conductive material which is extending along the female housing strips. The removable end blocks may be held in place in the ends of the female housing strips by any device or means, but preferably may be inserted and removed without the use of fasteners which may cause damage to components of the safety edge.
In a preferred embodiment, the removable endblocks are held in place in the ends of the female housing strips by a plunger which engages the female housing strip and by engagement with two locking pins which extend into the interior of the female housing strip. In the preferred embodiment the plunger is biased towards the female housing strip, preferably with a spring or an elastomeric material.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings, wherein:

FIGURE 1 is a pictorial view of a safety edge constructed in accordance with the teachings of the invention.
FIGURE 2 is a pictorial view of a female housing strip for the safety edge illustrated in FIGURE 1.
FIGURE 3 is a pictorial view of a male actuator strip for the safety edge illustrated in FIGURE 1.
FIGURE 4 is a pictorial view of a first electrical contact means assembly for the female housing strip illustrated in FIGURE 2.
FIGURE 5 is a pictorial view of a second electrical contact means assembly for the male actuator strip illustrated in FIGURE 3.
FIGURE 6 is a partially cut-away pictorial view of the safety edge illustrated in FIGURE 1, with the endblock removed.
FIGURE 7 is a pictorial view of an endblock for the safety edge illustrated in FIGURE 1.
FIGURE 8 is a pictorial view of an electrical connective member for use between two adjacent safety edge units of the safety edge illustrated in FIGURE 1.
FIGURE 9 is a pictorial view of an end cover plate for the safety edge illustrated in FIGURE 1.
FIGURE 10 is a pictorial view of a dust plug for the safety edge illustrated in FIGURE 1.
FIGURE 11 is a pictorial view of the safety edge illustrated in FIGURE 1 with end cover plate, dust plug and weather strip attached.
FIGURE 12 is a pictorial view of the safety edge illustrated in FIGURE 10 _g_ attached to a typical electrically operated overhead door.
FIGURE 13 is a partially cut-away detailed pictorial view of the safety edge as illustrated in FIGURE 11.
FIGURE 14 is a side view of a plastic alignment plug for the safety edge illustrated in FIGURE 1.
FIGURE 15 is a pictorial view of a preferred embodiment of a separate attachment flange for the safety edge illustrated in FIGURE 1.
FIGURE 16 is a pictorial view of an alternate embodiment of a separate attachment flange for the safety edge illustrated in FIGURE 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of safety edge, generally identified by reference numeral 20, will now be described with reference to FIGURES 1 through 16 as a safety edge for an overhead door.
Referring to FIGURES 1 to 3, the key components of safety edge 20 include an elongate female housing strip 22 and an elongate male actuator strip 24.
Referring to FIGURE 12, the length of female housing strip 22 and male actuator strip 24 can be equivalent to the width of any overhead door. In actual practice, female housing strip 22 and male actuator strip 24 will be made in safety edge units of standard lengths with a plurality of safety edge units being joined to make up any required width of safety edge 20, as will hereinafter be further explained. Female housing strip 22 is separately illustrated in FIGURE 2. Male actuator strip 24 is separately illustrated in FIGURE 3. It will be understood that the following description of safety edge 20 as employed on an overhead door bottom section is by way of example only, as the safety edge of the present invention may also be advantageously employed in other applications, such as, rolling steel door bottom rails, rolling shutter door bottom bars, as well as gates, windows, shutters, sliding panels and the like.

Referring to FIGURE 12, each female housing strip 22 has opposed ends 26. Referring to FIGURE 2, each female housing strip 22 has a "C" channel body which defines an interior cavity 30. "C" channel body 28 has both an integrally formed vertically extending integral attachment flange 32 and an integrally formed attachment groove 33.
Referring to FIGURE 13, integral attachment flange 32 serves as one means for attaching female housing strip 22 to an edge 34 of a door 36 and may be severed from the safety edge 20 by cutting or by some other method if the use of the integral attachment flange 32 is not required.
Referring to FIGURES 2, 15 and 16, the attachment groove 33 facilitates a second means for attaching the female housing strip 22 to an edge of a door 36 using a separate attachment flange 35 which comprises an attachment lug 37.
Alternatively, the integral attachment flange 32 and/or the attachment groove 33 may be formed with or otherwise connected to the male actuator strip 24 so that the male actuator strip 24 may be attached to an edge 34 of a door 36. In addition, the attachment groove 33 may be formed as part of the separate attachment flange 35 and the attachment lug 37 may be formed as part of either the female housing strip 22 or the male actuator strip 24.
The attachment groove 33 and the attachment lug 37 are complementary in order to provide a connection between the separate attachment flange 35 and the female housing strip 22. The separate attachment flange 35 may be any shape or size as may be required in order to mount the safety edge 20 to an edge of a door 36 or some other surface. Referring to FIGURE 15, a preferred separate attachment flange 35 is illustrated in which the flange 35 is vertically extending. Referring to FIGURE 16, an alternate separate attachment flange 35 is illustrated in which the flange 35 is horizontally extending and includes an attachment channel 39 for engaging an edge of the female housing strip 22 to provide a more positive attachment of the separate attachment flange 35 to the female housing strip 22.
In the preferred embodiment, the attachment groove 33 extends along the top of the female housing strip for the entire length of the female housing strip. The attachment groove 33 may however be located at any position on the female housing strip 22 or the male actuator strip 24.
Referring to FIGURE 2, "C" channel body 28 has an interior wall 38, an exterior wall 40, and a plurality of channels 42, 44 and 46 disposed between interior wall 38 and exterior wall 40. Each of channels 42, 44, and 46 extend between opposed ends 26. Channels 46 have longitudinally extending slots 47, the purpose of which will hereinafter be further described. Integral attachment flange 32 and exterior walls 40 have longitudinally extending exterior reinforcing ribs 48. It is preferred that female housing strip 22 and, in particular, integral attachment flange 32 be constructed of a lightweight plastic material. This enables portions of integral attachment flange 32 to be cut away, to accommodate a variety of obstacles, while still maintaining adequate support for female housing strip 22. Interior cavity 30 of female housing strip 22 has internal shoulders 50. Separate attachment flange 35 is also preferably constructed of a lightweight plastic material.
Within interior cavity 30 is positioned first electrical contact means 52.
First electrical contact means 52 can take a variety of forms, as long as it is compatible with a second electrical contact means 54 to complete a normally open circuit, as will hereinafter be further described.
In the preferred embodiment, first electrical contact means 52 includes a pair of first electrical contacts, each of the first electrical contacts comprising a positive electrical contact 52a and a negative electrical contact 52b in spaced relation. Positive electrical contact 52a and negative electrical contact 52b are separately illustrated in FIGURE 4. One of the pair of first electrical contacts is positioned at each of the opposed ends of the female housing strip 22.
Each of the pair of first electrical contacts comprising positive electrical contact 52a and negative electrical contact 52b consists of two copper strips to which are connected insulated conductive wires 56. These conductive wires 56 extend along the length of the female housing strip 22 to connect the pair of first electrical contacts electrically. When placed in position, positive electrical contact 52a and negative electrical contact 52b are accessible for electrical contact from both interior cavity 30 and from channels 42.

Referring to FIGURE 12, male actuator strip 24 is generally elliptical in transverse section and has opposed ends 64. Referring to FIGURE 3, male actuator strip 24 has a top edge 66 and external shoulders 68 which are spaced toward top edge 66.
Top edge 66 has second electrical contact means 70 at each of opposed ends 64.
Second electrical contact means 70 is a "bridge" contact that spans between positive electrical contact 52a and negative electrical contact 52b when the male actuator strip 24 is in a second position, as hereinafter will be further described.
Referring to FIGURE 6, male actuator strip 24 is telescopically received within the interior cavity 30 of female housing strip 22. Male actuator strip 24 is movable between a first position in which second electrical contact means 70 is spaced from first electrical contact means 52 and a second position in which second electrical contact means 70 engages first electrical contact means 52 to close a normally open circuit. Leaf-type springs (not shown) serve to bias male actuator strip 24 toward the first position and are positioned in the interior cavity 30 between the female housing strip 22 and the male actuator strip 24 . External shoulders 68 on male actuator strip 24 engage internal shoulders 50 within interior cavity 30 of female housing strip 22 to prevent male actuator strip 24 from being withdrawn from female housing strip when in the first position. Male actuator strip 24 moves to the second position to cause second electrical contact means 70 to come into contact with first electrical contact means 52 when an obstruction is encountered in its path of travel. Having first electrical contact means 52 at each of opposed ends 26 of female housing strip 22 and second electrical contact means 70 at each of opposed ends 64 of male actuator strip 24 enables each safety edge unit comprising the safety edge 20 to operate in a safe manner even when struck at one end only.
Preferably, one or both of the first and second electrical contact means 52,70 are pivotable about an axis that is perpendicular to the longitudinal axis of the male actuator strip 24 so that the normally open circuit can be closed even when only one end of the male actuator strip 24 is in the second position due to uneven telescoping of the male actuator strip 24 in the female housing strip 22. This pivoting function can be achieved in any manner such as by mounting the first and/or second electrical contact means 52,70 on a pivoting axis. In the preferred embodiment, the second electrical contact means 70 are mounted so that they "float" relative to the male actuator strip 24 and are thus pivotable. This "floating" function is achieved in the preferred embodiment by mounting the second electrical contact means 70 on the male actuator strip 24 with a biasing device. Although any type of biasing device may be used, in the preferred embodiment the biasing device is comprised of an elastomeric material 75 which is contained in a cavity 77 in the upper surface of the male actuator strip 24, and the second electrical contact means 70 are mounted on the elastomeric material 75 using a wire 79 which extends around both the second electrical contact means 70 and the elastomeric material 75 and is held in place with a block 80 which is inserted in the male actuator strip 24.. Alternatively, the first electrical contact means 52 may pivot in addition to or instead of the second electrical contact means 70.
Referring to FIGURE 7, a removable endblock 78 is illustrated. Preferably each safety edge unit includes an endblock 78 at each of the opposed ends of the female housing strip 22 to provide strength to the female housing strip 22 and to assist in maintaining the male actuator strip 24 in its proper orientation within the interior cavity 30 of the female housing strip 22. The endblocks 78 also provide a conduit for conductive material which extends through the female housing strip 22.
Referring to FIGURES 1 and 7, each endblock 78 is attached to the female housing strip 22 in three separate locations which eliminate the use of screws or other fasteners in the attachment of the endblocks 78. Each endblock 78 is attached to the female housing strip 22 at one location with a plunger 81 associated with the endblock 78 which plunger 81 engages a discontinuity in the female housing strip 22. In the preferred embodiment, the plunger 81 is biased towards engagement with the female housing strip 22 by an elastomeric material 82, but other forms of biasing device may be used.
Referring to FIGURE 1, in the preferred embodiment each end of each female housing strip 22 is equipped with a pair of locking pins 83 which extend from the exterior of the female housing strip 22 through the channels 44 on both sides of the female housing strip 22 and protrude into the interior cavity 30 of the female housing strip 22. Referring to FIGURE 13, in the preferred embodiment each endblock 78 includes a lower endblock cavity 78a. Each endblock 78 is attached to the female housing strip 22 at second and third locations by engaging the lower endblock cavity 78a with the locking pins 83 which protrude into the interior cavity 30 of the female housing strip 22. Further alignment and support for the endblocks 78 is achieved by complementary notches and flanges 84 on the endblock 78 and the female housing strip 22.
Referring to FIGURE 12, the electrical circuit is formed by connecting conductive wires 56 to the electrical door opener 86 by means of an electrical cord 88.
In the preferred embodiment, the conductive wires 56 for each safety edge unit extend between and terminate at each first electrical contact means 52 comprising the pair of first electrical contacts, except as may be required to facilitate the formation of the electrical circuit between the safety edge 20 and the electrical door opener 86, in which case the conductive wires 56 also extend through an endblock 78 and through an access port 85 which can be drilled or cut into the female housing strip 22 on-site, where they may be connected to the electrical cord 88 which in turn is connected to the electrical door opener 86.
As indicated, safety edge 20 is preferably modular and is preferably comprised of a plurality of safety edge units connected together both structurally and electrically. Referring to FIGURE 12, two or more substantially identical safety edge units when coupled together can achieve a required length of safety edge 20 to correspond to the length of an edge 34 of door 36 on which they are to be installed.
Each safety edge unit is constructed in such a manner so as to allow its use individually for door sections of small length or in a plurality of safety edge units connected together for use on door sections of greater length.
Referring to FIGURES 1, 8 and 14, structural and electrical connection between two identical safety edge units is in the preferred embodiment accomplished using a connector comprising copper interlocks 90 and plastic alignment plugs 92 as connective members. Copper interlocks 90 extend through a gasket 94 into channels 42 of female housing strip 22 where they make an electrical connection with electrical contacts 52a and 52b. In order to prevent copper interlocks 90 from going completely into channels 42, the copper interlocks 90 are provided with a discontinuity 91 which limits the distance that copper interlocks 90 can be extended into channels 42. Copper interlocks 90 are preferably made of copper.
Referring to FIGURE 14, plastic alignment plugs 92 similarly extend into channels 44. Plastic alignment plugs 92 provide a structural connection between adjacent safety edge units which helps to maintain the alignment of a female housing strip 22 of one safety edge unit with a female housing strip 22 of a next adjoining safety edge unit. The plastic alignment plugs 92 may be comprised of any shape or size which is compatible with the corresponding channels 44 in the female housing strips 22 to provide a firm connection between adjacent female housing strips 22 while permitting limited flexure of the joint between adjacent female housing strips 22. In a preferred embodiment, each of the plastic alignment plugs 92 is comprised of two pairs of tines 93, with each pair of tines 93 being insertable in a channel 44 of a female housing strip 22 to surround and engage the locking pins 82 which extend through channels 44 with a locking pin engagement surface 95.
Referring to FIGURE 9, an optional end cover plate 96 is illustrated. End cover plate 96 preferably has protruding plugs 98 that are adapted to be received in channels 44 of female housing strip 22. Referring to FIGURE 11, when connection to an adjacent safety edge unit is not required, end cover plate 96 may be used to complete the terminal end of a female housing strip 22. The end cover plate 96 is preferably attached to the safety edge 20 with a screw 97 which fastens the end cover plate 96 to an endblock 78.
Referring to FIGURE 10, an optional foam rubber dust plug 100 is illustrated. Referring to FIGURE 11, dust plug 100 may be used to complete any or all of the opposed ends 64 of a male actuator strip 24. Dust plug 100 may be attached to the safety edge 20 by pressing one end of the dust plug 100 into the lower endblock cavity 78a of the endblock 78.
Referring to FIGURE 11, it is preferred that a rubber weatherstrip 102 be attached to female housing strip 22 so that it covers male actuator strip 24.
This weatherstrip 102 prevents debris from entering into interior cavity 30 of female housing strip 22 and may also function to provide a seal between the door edge 34 and the floor when the door 36 is closed. Weatherstrip 102 is retained in channels 46 and extends out through slots 47. Weatherstrip 102 is easily slid into position by sliding along slot 47 from one of opposed ends 64.
The use and operation of safety edge 20 will now be described with reference to FIGURES 1 through 16. Referring to FIGURE 12, a plurality of safety edge units are secured in end to end relation along edge 34 of door 36 using connectors as depicted in FIGURES 8 and 14 to form a complete safety edge 20. Referring to FIGURE
13, each safety edge unit is secured to edge 34 of door 36 by inserting screws 104 either through integral attachment flanges 32 or through separate attachment flanges 35.
Attachment flanges 32,35 may be cut away as required to avoid obstacles, such as bottom lifting fixture 106. If separate attachment flanges 35 are used, the female housing strips 22 may be attached to the separate attachment flanges 35 either before or after the flanges 35 are secured to the edge of door 36. Integral attachment flange 32 may be severed from the safety edge 20 if a separate attachment flange 35 is to be used.
Referring to FIGURE 1, the end to end connection of adjacent safety edge units is accomplished using connectors by extending copper interlocks 90 into channels 42 of female housing strip 22 where they make an electrical connection with electrical contacts 52. Plastic alignment plugs 92 similarly extend into channels 44 to provide a structural connection and to add stability. Removable endblocks 78 are also inserted in each end of each female housing strip 22 and are secured to the female housing strip 22 with the plunger 81 and the locking pins 82. Gaskets 94 are provided between copper interlocks 90 on adjacent endblocks 78. Preferably the ends of the safety edge where a female housing strip 22 is not attached to an adjacent female housing strip 22 are equipped with an end cover plate 96 and a dust plug 100. An access port 85 may be drilled or otherwise provided in the female housing strip 22 adjacent to the end cover plate 96 to facilitate connection of the safety edge 20 to a power supply.
Referring to FIGURE 6, male actuator strip 24 moves to the second position to cause second electrical contact means 70 to come into contact with first electrical contact means 52 when an obstruction is encountered in its path of travel. The engagement of the second electrical contact means 70 and the first electrical contact means 52 completes a previously open electrical circuit which includes the electrical door opener 86, the electrical cord 88, the conductive wires 56 and the first electrical contact means 52. The electrical contact between second electrical contact means 70 and first electrical contact means 52 can be made at either of opposed ends 64 and 26, respectively, which enables each safety edge unit to operate independently and in a safe manner even when struck at one end only. Positive contact between the first and second electical contact means 52,70 is enhanced by the floating action of the second electrical contact means 70 relative to the male actuator strip 24.
Referring to FIGURE 12, using a plurality of safety edge units in the safety edge 20 also assists in improving the seal between the door edge 34 and the floor when the door 36 is closed by virtue of the independent action of each male actuator strip 24 in each safety edge unit. This independent action also better accommodates an angular drainage slope on a floor because the telescoping movement of a relatively short length of male actuator strip 24 will more easily follow an angled floor line when deflected by the closing of the door 36.
It will be apparent to one skilled in the art that modifications may be made to the illustrated preferred embodiment without departing from the spirit and scope of the invention as hereinafter defined in the claims. For example and as discussed above, the safety edge 20 may be configured so that the male actuator strip 24 includes means for attaching the safety edge to a door and the female housing strip 22 is movable relative to the male actuator strip 24 between a first position in which the second electrical contact means 70 is spaced from the first electrical contact means 52 and a second position in which the second electrical contact means 70 engages the first electrical contact means 52 to form a complete electrical circuit.

Claims (24)

1. A safety edge, comprising:
(a) a female housing strip having an interior cavity in which is positioned at least one first electrical contact means;
(b) a male actuator strip having at least one second electrical contact means, the male actuator strip being telescopically received in the female housing strip, the male actuator strip being movable between a first position in which the second electrical contact means is spaced from the first electrical contact means and a second position in which the second electrical contact means engages the first electrical contact means to close a normally open circuit; and (c) means for attaching the safety edge to a surface;
wherein the male actuator strip defines a longitudinal axis and wherein at least one of the first electrical contact means and the second electrical contact means is pivotable about an axis perpendicular to the longitudinal axis of the male actuator strip.

2. The safety edge as defined in Claim 1, wherein the safety edge comprises a safety edge unit, and wherein a plurality of safety edge units are connected together.

3. The safety edge as defined in Claim 2, further comprising a connector comprising at least one connective member for connecting adjacent safety edge units together both structurally and electrically.

4. The safety edge as defined in Claim 3, wherein each female housing strip of the plurality of safety edge units has opposed ends, wherein adjacent female housing strips have adjacent opposed ends, and wherein the connector connects the adjacent opposed ends of the adjacent female housing strips.

5. The safety edge as defined in Claim 4, wherein each female housing strip has an interior wall, an exterior wall and a plurality of channels disposed between the interior wall and the exterior wall, the channels extending between the opposed ends of the female housing strip, and wherein the connector comprises at least one connective member insertable into at least one of the plurality of channels at the adjacent opposed ends of the adjacent female housing strips.

6. The safety edge as defined in Claim 5, wherein the first electrical contact means comprises a pair of first electrical contacts positioned in the interior cavity of each female housing strip, one of the pair of first electrical contacts positioned at one of the opposed ends of the female housing strip and another of the pair of first electrical contacts positioned at another of the opposed ends of the female housing strip, and wherein the pair of first electrical contacts is electrically connected.

7. The safety edge as defined in claim 6, wherein the second electrical contact means is pivotable relative to the male actuator strip.

8. The safety edge as defined in claim 7, wherein the second electrical contact means is mounted on the male actuator strip using a biasing device so that the second electrical contact means floats relative to the male actuator strip.

9. The safety edge as defined in claim 8, wherein the biasing device is comprised of an elastomeric material which is contained within a cavity defined by the male actuator strip.

10. The safety edge as defined in Claim 1, wherein the first electrical contact means includes a positive electrical contact and a negative electrical contact in spaced relation, and the second electrical contact means on the male actuator strip includes at least one bridge contact that spans between the positive electrical contact and the negative electrical contact to close the normally open circuit.

11. The safety edge as defined in claim 10, wherein the second electrical contact means is pivotable relative to the male actuator strip.

12. The safety edge as defined in claim 11, wherein the second electrical contact means is mounted on the male actuator strip using a biasing device so that the second electrical contact means floats relative to the male actuator strip.

13. The safety edge as defined in claim 12, wherein the biasing device is comprised of an elastomeric material which is contained within a cavity defined by the male actuator strip.

14. The safety edge as defined in Claim 1, wherein the female housing strip has opposed ends, wherein one of the first electrical contact means is positioned at each of the opposed ends of the female housing strip, wherein the male actuator strip has opposed ends, and wherein one of the second electrical contact means is positioned at each of the opposed ends of the male actuator strip such that one of the first electrical contact means is engagable with one of the second electrical contact means to close the normally open circuit at either of the opposed ends of the female housing strip.

15. The safety edge as defined in claim 14, wherein the second electrical contact means is pivotable relative to the male actuator strip.

16. The safety edge as defined in claim 15, wherein the second electrical contact means is mounted on the male actuator strip using a biasing device so that the second electrical contact means floats relative to the male actuator strip.

17. The safety edge as defined in claim 16, wherein the biasing device is comprised of an elastomeric material which is contained within a cavity defined by the male actuator strip.

18. The safety edge as defined in claim 1, wherein the attaching means is comprised of an attachment flange and wherein the attachment flange is removably attachable to either the female housing strip or the male actuator strip.

19. The safety edge as defined in claim 18, wherein the female housing strip and the attachment flange are comprised of an attachment groove and a complementary attachment lug for attaching the attachment flange to the female housing strip.

20. The safety edge as defined in claim 19, wherein the female housing strip is comprised of the attachment groove and wherein the attachment flange is comprised of the attachment lug.

21. A safety edge, comprising:
(a) a female housing strip having an interior cavity in which is positioned at least one first electrical contact means;

(b) a male actuator strip having at least one second electrical contact means, the male actuator strip being telescopically received in the female housing strip, the male actuator strip being movable between a first position in which the second electrical contact means is spaced from the first electrical contact means and a second position in which the second electrical contact means engages the first electrical contact means to close a normally open circuit; and (c) an attachment flange for attaching the safety edge to a surface, which attachment flange is removably attachable to either the female housing strip or the male actuator strip.

22. The safety edge as defined in claim 21, wherein the female housing strip and the attachment flange are comprised of an attachment groove and a complementary attachment lug for attaching the attachment flange to the female housing strip.

23. The safety edge as defined in claim 22, wherein the female housing strip is comprised of the attachment groove and wherein the attachment flange is comprised of the attachment lug.

24. A safety edge comprising a plurality of safety edge units connected together, each safety edge unit comprising:
(a) a female housing strip having an interior cavity in which is positioned at least one first electrical contact means;

(b) a male actuator strip having at least one second electrical contact means, the male actuator strip being telescopically received in the female housing strip, the male actuator strip being movable between a first position in which the second electrical contact means is spaced from the first electrical contact means and a second position in which the second electrical contact means engages the first electrical contact means to close a normally open circuit; and (c) an attachment flange for attaching the safety edge to a surface, which attachment flange is removably attachable to either the female housing strip or the male actuator strip;

wherein the male actuator strip defines a longitudinal axis and wherein at least one of the first electrical contact means and the second electrical contact means is pivotable about an axis perpendicular to the longitudinal axis of the male actuator strip.