Combination key and transponder carrier

Abstract: An improved combination key and transponder assembly is provided wherein the head (11) of the key includes an elongate slot that passes through the head. A carrier (15) is moulded into the slot disposed in the key head. The carrier has a hollow interior (19) bound by a plurality of tabs (21) for frictionally retaining a transponder (22) in the carrier. After the transponder is inserted into the carrier (19), the key head, carrier and transponder are inserted into a mould and an outer sheath is moulded around the head, carrier and transponder. The resulting assembly has a slim profile and may be mounted on a standard sized key chain or key holder. The assembly may be manufactured using an automated process without manual sub-assembly steps.

Description: Field of the Invention: The present invention relates generally to keys used in combination electronic and mechanical lock systems. More specifically, the present invention relates to an improved design for a key which is equipped with a transponder. Still more specifically, the present invention relates to an improved structure for attaching a transponder to a key and an improved method of manufacturing a combination key and transponder assembly. BACKGROUND OF THE INVENTION It is known to equip keys used for rotating the tumblers of mechanical locks with electronic devices such as small lights or transponders for sending signals to electronic anti-theft devices or electronic lock mechanisms. Typically, the transponders are encased in a plastic housing which is mounted to the head of the key. However, two additional assembly steps are required. Specifically, the transponder must be assembled to the housing and the housing then must be attached or otherwise assembled to the key head. Further, currently-available housings that attach a transponder to a key head are large and bulky and are not amenable to attachment to a standard key chain. Document EP-A-0 685 620 shows for example an assembly according to the first part of claim 1. Therefore, there is a need for an improved combination key and transponder whereby the transponder is attached to the key in an efficient manner using automated equipment and whereby the size of the key head, transponder and housing or casing is relatively small so that the combination easily fits on a standard key ring. Further, there is a need for an improved combination key and transponder which can be manufactured using automated equipment and which will not require any sub-assembly steps to be carried out manually. SUMMARY OF THE INVENTION The present invention satisfies the aforenoted needy providing a combination key and transponder assembly according to claim 1. As a result, a combination key and transponder are provided whereby the head of the key, which includes the transponder and an encapsulating sheath, is relatively thin thereby enabling it to be easily accommodated on a standard key ring. Further embodiments are defined in dependent claims 2-9. The present invention also provides a method of manufacturing a combination key and transponder assembly according to claim 10. Further embodiments are defined in dependent claims 11 and 12. BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the present invention, reference should now be made to the embodiment illustrated in greater detail in the accompanying drawing and described below by way of an example of the present invention. In the drawing: Figure 1 is a perspective view of a key blank and carrier made in accordance with the present invention; Figure 2 is a perspective view of the key blank and carrier shown in Figure 1 with the carrier inserted into a slot disposed in the key blank and further illustrating a transponder; Figure 3 is a schematic plan view of the key blank, carrier and transponder inserted into a mold for molding an outer sheath; and Figure 4 is a plan view of the key blank, carrier, transponder and outer sheath of the present invention. It should be understood that the drawings are not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS Turning first to Figure 1, a key blank 10 is illustrated which includes a head 11 that is connected to a blade 12. The head 11 includes an elongated slot 13 which, in the preferred embodiment illustrated in Figure 1, is disposed in a general alignment with the blade 12. The head also includes an opening 14 for mounting the blank 10 onto a key chain. Figure 1 also illustrates a transponder carrier 15. The carrier 15 is accommodated in the slot 13. In a preferred embodiment, the carrier 15 is permanently molded into the slot 13. Further, the carrier 15 is also configured to include outer flanges 16 and 17 with a central body 18 disposed therebetween. The central body 18 includes a hollow interior 19. At opposing sides of the central body 18 or the opposing flanges 16, 17, a plurality of tabs shown at 21 are provided. The tabs 21 frictionally engage the transponder 22 (see Figure 2) and trap the transponder 22 inside the hollow interior 19 of the carrier 15. Each flange 16, 17 or each opposing side of the central body 18 may include one or more tabs 21. It is preferable that at least one tab 21 be included at each flange 16, 17 or opposing side of the central body 18 for trapping the transponder 22 in the hollow interior 19. Turning to Figure 2, after the carrier 15 is molded into the slot 13 or forced into the slot 13, the transponder 22 is inserted into the hollow interior 19, past the tabs 21. After the transponder 22 is inserted into the carrier 15, an outer sheath 23 is molded over the entire head 11, carrier 15 and transponder 22 (see Figure 4). Referring to Figure 3, the sheath 23 is molded using an injectable mold 24 by placing the key 10 with carrier 15 and transponder 22 disposed therein into the mold 24 and injecting liquid plastic material from a reservoir 25 into the cavity shown at 26. Because the slot 13 extends through the head 11 and further because the carrier 15 includes the hollow interior 19 which passes through the carrier 15, molten plastic can be communicated through the carrier 15 and around the transponder 22 to secure the transponder 22 in place and provide a sturdy structure. As a result, a key 10 can be equipped with a transponder 22 and encasing sheath 23 without utilizing a bulky casing or housing for the transponder 22. The key 10 with sheath 23 as shown in Figure 4 may be easily attached to a standard key chain or key ring. Thus, the employment of a slot 13 that extends through the head 11 of the key 10 and further which accommodates the transponder 22 therein saves space without adversely affecting the structural integrity of the key 10. Accordingly, to fabricate the key and transponder assembly 30 shown in Figure 4, a key 10 is provided with a pre-punched slot 13 disposed in the head 11 of the key 10. A carrier 15 is then molded into the slot 13 or forced into the slot 13 if the carrier 15 is provided in a pre-molded state. Because of the advantages of having the outer flanges 16, 17, the preferred method of fabricating the assembly 30 includes a step of molding the carrier 15 into the slot 13. After the carrier 15 is in place, the transponder 22 is forced past the tabs 21 and into the hollow interior 19 of the carrier 15. Then, the key 10, carrier 15 and transponder 22 are placed into a mold 24 which includes a cavity 26 for forming the outer sheath 23. Liquid plastic is then injected into the cavity 26 thereby forming the sheath 23 thereby producing the assembly 30 as shown in Figure 4.

Claims: A combination key and transponder assembly comprising: a key blank (10) having a key head (11) with a top and a bottom surface, the head having a first aperture (13) formed therein, the assembly further comprising a moulded plastics material transponder carrier (15) arranged to be received in the first aperture (13) and having portions (16, 17) projecting above at least one of the surfaces of said key head (11), said portions (16, 17) having peripheral areas overlying said at least one surface of the key head, said carrier (15) having a second aperture (19) therethrough dimensioned to receive a transponder (22), the second aperture having two opposing sidewalls, the opposing sidewalls having raised protuberances (21) locally reducing the width of the second aperture (19), the transponder (22) being dimensioned to fit within the second aperture (19), the transponder (22) also having a width dimensioned to be at least as great as the width of the second aperture (19) whereby, upon insertion of the transponder into the second aperture, the transponder will be held in the second aperture by said protuberances (21), the assembly further comprising a moulded key head sheath (23) moulded around portions of said key head covering said carrier (15) and fixing the carrier in the key head, characterized in that the second aperture (19) is open to at least the one surface of the key head when the carrier (15) is disposed in the first aperture (13), and said sheath extends into said second aperture (19) and fixes said transponder (22) in said second aperture (19). An assembly as claimed in claim 1, characterised in that the first aperture (13) passes through the key head (11). An assembly as claimed in claim 1, characterised in that the first aperture (13) passes through the key head (11) and the second aperture (19) of the carrier (15) passes through the carrier. An assembly as claimed in any preceding claim, characterised in that the first aperture (13) passes through the key head (11) and the carrier (15) comprises a central body (18) disposed between two opposing outer flanges (16, 17), the central body (18) being disposed in the first aperture and the outer flanges (16, 17) being disposed on the opposing top and bottom surfaces of the key head, the central body (18) defining a hollow interior that provides fluid communication through the head. An assembly as claimed in claim 4, characterised in that each flange (16, 17) comprises at least one inwardly protruding tab (21) for frictionally engaging the transponder (22). An assembly as claimed in claim 4 or 5, characterised in that the first aperture (13) is a slot and each flange (16, 17) of the carrier (15) extends around the slot in the head, each flange (16, 17) further comprising two tabs (21) disposed on opposing sides of the slot for frictionally retaining the transponder (22)in the hollow interior of the carrier and between the two flanges. An assembly as claimed in claim 1, characterised in that the key comprises a blade (12) connected to the head (11), the first aperture (13) being elongate and disposed in alignment with the blade, the first aperture (13) passing through the head, the carrier (15) comprises a central body (18) that is matably received in the first aperture and disposed between two flanges (16, 17), the flanges being disposed on the opposing top and bottom surfaces of the head with the head and central body sandwiched between the flanges, the central body (18) of the carrier defining a hollow interior (19), and the first and second flanges (16, 17) each comprising a plurality of deformable and inwardly protruding tabs (21) for capturing the transponder (22) between the tabs and in the hollow interior (19) of the carrier. An assembly as claimed in claim 7, characterised in that the hollow interior of the carrier (15) provides communication through the carrier and through the key head and the moulded sheath (23) extends through the hollow interior (19) and past the transponder (22). An assembly as claimed in claim 7, characterised in that the moulded sheath (23) extends through the hollow interior (19) and past the transponder (22). A method of manufacturing a combination key and transponder assembly, the method comprising the following steps: providing a key comprising a head (11) having two opposing sides with a slot (13) disposed therein that extends through the head and between the opposing sides; moulding a carrier (15) in the slot, the carrier comprising a central body (18) having a hollow interior (19) for receiving a transponder (22), the hollow interior providing communication through the central body, the carrier further comprising two opposing flanges (16, 17) disposed on opposing sides of the head, the flanges (16, 17) extending around the slot (13) and each flange comprising two tabs (21) disposed on opposing sides of the slot; inserting the transponder (22) into the central body of the carrier after the carrier is moulded into the slot (13); and moulding a sheath (23) around the head, slot, carrier and transponder and at least partially through the hollow interior and around the transponder. A method as claimed in claim 10, characterised in that the tabs (21) are deformable for frictionally retaining the transponder (22) in the hollow interior during the step of moulding the sheath (23). A method as claimed in claim 10 or 11, characterised in that each flange has two pairs of spaced-apart tabs (21), each pair of spaced-apart tabs being disposed on opposing sides of the slot (13).

Inventors: DAVIS DOUGLAS, HARRELSON DONALD, DAVIS, DOUGLAS, HARRELSON, DONALD
Applicants: ILCO UNICAN INC, ILCO UNICAN CORPORATION
Application year: 1999
Main classification: E05B49
IPC codes: G07C9, E05B19