KEY PROVIDED WITH BUILT-IN TRANSMITTER ELEMENT AND KEY BODY

Abstract: A transmitting element 18 is embedded into a resin container 16 by insert-molding. After the resin container 16 has been attached to a base portion 12B of a key body 12, an outer soft resin skin 34 is integrally formed onto the resin container 16 and the base portion 12B, so that a key knob 14 is formed. The transmitting element 18 is reliably fixed into the base portion 12B via the resin container 16, so that the transmitting element 18 can be protected from external force applied to the key knob 14.

Description: BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to a key provided with a built-in transmitting element in which a transmitting element is embedded at the interior of the key. DESCRIPTION OF THE RELATED ART Conventionally, in order to unlock a lock with a key, a plurality of pins provided at the internal cylinder of the lock are driven by mechanical projections and recesses or a magnetic force by an embedded magnet provided at the insertion portion of the key body so that pins bridging over the boundary surface of the internal cylinder and the fixed external cylinder are moved, and the internal cylinder is rotated within the external cylinder. However, when such a combination of a mechanical key and a lock is used, the lock can be unlocked, if a reproduced key has the same shape as that of an original key. In addition, it is difficult to make defensive structures against destructive activities with such combination. In particular, in case of keys for vehicles, since an engine starter can be operated by directly connecting electric wires without using the key, it is difficult to achieve complete key functions by use of a conventional combination of a key and a lock To solve this problem, in addition to the insertion portion of a key having mechanical projections and recesses or magnetic force generating portion, a key with a built-in transmitting element for transmitting a specified ID code has been proposed. According to an embodiment of such key, only when a receiving element installed in a vehicle receives the specified ID code, the engine of the vehicle can be started or continuously operated so that the movement of the vehicle due to a direct connection of electric wires or a mechanical destruction can be prevented. For such conditions, since the transmitting element is required to be small and metal portions are not disposed on the outer periphery of the transmitting element, the transmitting element is not generally disposed at the insertion portion of the key body, but at a grip portion (i.e. key knob) formed by non-metal member such as resin which does not interfere in transmitting functions. In such a key with a built-in transmitting element, the grip portion of the key is constituted by resin cases which are divided into two portions, so that the resin cases clamp the transmitting element and the base portion of the key body by screwing with bolts. Further, when a battery is exhausted, since the transmitting element cannot transmit the ID code and the vehicle engine cannot be started, a key with a built-in transmitting element which needs no battery has been adopted in recent years. However, since the grip portion is formed by non-metal member such as resin or the like, there has been a drawback that when the key body is rotated, external force is applied to the transmitting element, so that the transmitting element is damaged. Moreover, in an assembling structure in which two resin cases are fastened by screws, as the key is used for a long period of time, the screws are loosened and the resin cases are opened, so that the embedded components such as a transmitting element and a battery or the like may be released from the resin cases and thereby dropped from the resin cases. In such a case, there has been a drawback in that since the ID code is not transmitted, the vehicle engine cannot start. Further, there is a possibility that when the screws are loosened, a gap is formed between the resin cases, dust and/or water penetrate thereinto and affect the transmitting element which has been embedded in the resin cases. Also in the assembling structure in which the resin cases are fastened by screws, a work for screwing is trouble some and the key assembling is time-consuming. Because a certain degree of hardness is required for the resin cases to be securely screwed together, a slightly resilient material whose touch feel is comfortable cannot be used as a grip portion of a key. Document US 4,200,227 discloses a key according to the preamble of claim 1. However, the key disclosed therein has the disadvantage of possible injuries caused by the hard key head in case of accident. Document FR 2 626 526 discloses a key with a hard resin holder and an outer soft skin covering the holder. However, the key disclosed therein does not have a transmitting element nor is it disclosed to reliably fix a transmitting element in the hard resin holder by means of the outer soft skin. SUMMARY OF THE INVENTION In view of the above-described facts, it is an object of the present invention to provide a key with a built-in transmitting element which is resistant against external force such as torsion, and which has a structure in which the transmitting element is reliably embedded in the key. Further, it is another object of the present invention to provide a key with a built-in transmitting element and a key body in which any screwing work is not required for manufacturing or assembling the key, the transmitting element does not fall off from a grip portion of the key, and dust and/or water do not penetrate into the grip portion. Finally it is an object to improve touch feel during key operation. This object is solved by a key comprising the features of claim 1. The outer soft skin is formed onto the holding member and the key body. In this way, the holding member and the key body are covered with the outer soft skin, so that the transmitting element is reliably fixed into the key body. Further, the transmitting element is sealed by the outer soft skin and is thereby protected from external force acting thereon. Moreover, the present invention concerns a key with a built-in transmitting element comprising a transmitting element, a supporting member into which the transmitting element is accommodated and which is mounted in a base portion of a key body, and an outer soft skin which is formed onto the supporting member and the key body to fix the transmitting element into the key body. Accordingly, the transmitting element is accommodated into the supporting member, the supporting member is mounted to the base portion of the key body, and the outer soft skin is formed onto the supporting member and the key body. On the other hand, the exposed outer periphery of the hard resin is covered with an outer soft skin, so that touch feel during the key operation is improved. Moreover, an aspect of the present invention is a key with a built-in transmitting element in which the accommodation portion is formed such that the transmitting element which is accommodated into the accommodation portion can be disposed to be spaced apart from the key body at a predetermined distance. Accordingly, the electric wave transmitted by the transmitting element is not interfered by the metal key body is reliably transmitted. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a front view of a key according to a preferred embodiment of the present invention; Fig. 2 is an exploded perspective view showing a portion except a key knob according to the embodiment of Fig. 1; Fig. 3 is a front view showing a portion except a key knob according to the embodiment of Fig.1; Fig. 4 is a circuit diagram of a transmitting element and a control module; Fig. 5 is a side view of a vehicle showing a state in which the control module is disposed at the interior of the vehicle. EMBODIMENT A preferred embodiment of the present invention is shown in Figs. 1 through 3. Fig. 1 shows the key body 12, the transmitting element 18, a holder 76, and the key knob 14 as a grip portion. Among these members, as shown in Fig. 2, the base portion 12B of the key body 12 is rectangular-shaped and is wider than the insertion portion 12A, and has a hole 12H formed therein. The insertion portion 12A is used for insertion into a key cylinder 24 provided in a steering column 22 of a vehicle 20 shown in Fig. 5. The holder 76 is made of plastic and has a rectangular container shaped configuration. The holder 76 is provided with a first accommodation portion 77 for accommodating the base portion 12B of the above key body 12 and a second accommodation portion 78 for accommodating the transmitting element 18, the accommodation portions 77 and 78 being partitioned by a partition wall 79. Further, the above accommodation portions 77 and 78 of the holder 76 have insertion openings 62 and 63, respectively, which are formed on a coplanar surface of the holder 76. A projection 67 projects from one of the inner surfaces of the accommodation portion 77 at the innermost portion of the inner surface. A projection 72 projects from an opening edge portion on one of the inner surfaces of the accommodation portion 78. Since the holder 76 is structured as described above, the base portion 12B of the key body 12 is inserted from the insertion opening 62 into the first accommodation portion 77, the projection 67 is engaged with the hole 12H, so that the base portion 12B of the key body is engaged with the holder 76. On the other hand, the transmitting element 18 is inserted into the second accommodation portion 78, the projection 72 is engaged with the back edge portion of the transmitting element 18, so that the transmitting element 18 is engaged with the holder 76. Further, the base portion 12B of the key body 12 and the transmitting element 18 are set in a forming mold (not shown). A molten resin is injected into the forming mold from the insertion portion 12A side which is a direction indicated by an arrow A in Fig. 3, so that injection traces of the molten resin cannot be exposed. Accordingly, the base portion 12B of the key body 12 and the transmitting element 18 are covered with the resin, so that the above key knob 14 is formed by insert-molding. In this way an outer soft skin is formed on the hard resin holder 76. Further, the resin holder 76 is preferably made of such resin as polyacetal resins and polyester resins such as polybutylenetelephthalate resin or the like, has a predetermined hardness, and ought to have a strength enough to endure a force applied to the key knob 14 by a user because the key knob 14 serves as a user operating force input portion. Meanwhile, the outer resin skin is made of a relatively soft synthetic resin such as soft polyvinylychloride resin or the like. As shown in Fig. 5, a control module 40 is mounted in the vicinity of the steering column 22. The control module 40 is preferably disposed inside the cover of the steering column 22 so that the control module 40 cannot be visually found from outside. As shown in Fig. 4, in the control module 140, a transmitting and receiving coil 142, a transmitting and receiving circuit 143, a control circuit 144 and a memory 146 are connected each other. The control circuit 144 is connected to a vehicle control circuit 150 via an interface circuit 148. Accordingly, when a vehicle engine is started or a receiving signal is generated in the transmitting and receiving coil 142, the control circuit 144 of the control module 140 transmits an actuation signal from the transmitting and receiving coil 142 to the transmitting element of the key 10 via the transmitting and receiving circuit 143. An ID code from the transmitting element 18 of the key 10 is received by the transmitting and receiving coil 142 and judged by the control circuit 144. A registration code writing device 152 is connected to the control circuit 144 so that an ID code can be written therein. On the other hand, a transmitting and receiving coil 154, a transmitting and receiving circuit 155, a control circuit 156 and a memory 158 are provided to be connected each other in the transmitting element 18. Accordingly, an electromotive force is generated in the transmitting and receiving coil 154 in the transmitting element 18 by current generated in the transmitting and receiving coil 142. The electromotive force actuates the control circuit 156 through the transmitting and receiving circuit 155 and the ID code stored in the memory 158 is transmitted from the transmitting and receiving coil 154 to the transmitting and receiving coil 142. When the transmitting and receiving coil 142 receives the ID code it transmits the same to the control circuit 144 through the transmitting and receiving circuit 143. Therefore, the control circuit 144 collates the ID code thus received with the ID code stored in the memory 146. When it is determined through this collation that the ID codes are identical to each other, a signal is transmitted from the control circuit 144 to the vehicle control circuit 150 through the interface circuit 148 so that the vehicle engine can start or continuously run. When the received ID code is different from the ID code stored in the memory 146, another signal is transmitted to the vehicle control circuit 150 to disable the vehicle engine from starting, or to stop the running of the vehicle engine. The transmitting and receiving circuit 155, the control circuit 156 and the memory 158 in the transmitting element 18 are constituted as a single IC. The external dimensions of the transmitting element 18 are, for example, 1 mm in diameter and 10 mm in length. Next, operations of the key according to the first embodiment will be given hereinafter. When the key 10 is rotated by holding the key knob 14, the inner cylinder of the key cylinder 24 into which the key 10 is inserted is rotated together with the key 10, and the starter is actuated by the vehicle control circuit 50 so that the vehicle engine starts. At the same time, the transmitting and receiving circuit 143 of the control module 140 receives a signal announcing that the vehicle engine has started from the vehicle control circuit 150, and the control circuit 144 actuates the transmitting and receiving circuit 143 to pass a current to the transmitting and receiving coil 142. Accordingly, the transmitting element 18 of the key 10 disposed in the vicinity of the transmitting and receiving coil 142 causes an electromotive force in the transmitting and receiving coil 154. The control circuit 156 is actuated by the electromotive force and the ID code stored in the memory 158 is transmitted from the transmitting and receiving coil 154. The transmitted signal is received by the transmitting and receiving coil 142 and transmitted to the control circuit 144 through the transmitting and receiving circuit 143. The control circuit 144 transmits a signal to the vehicle control circuit 150 when the ID code received by the control circuit 144 is identical to the ID code stored in the memory 146 and the vehicle control circuit 150 is allowed to continue to run the vehicle engine. However, when the received ID code is different from the stored ID code in the memory 146, or an ID code is not received, the control circuit 144 transmits a different signal to the vehicle control circuit 150, so that the vehicle control circuit 150 makes the engine to stop. Further, in the preferred embodiment, the key 10 transmits the ID code to the control module 140 after the vehicle engine has started. However, the ID code may be transmitted when the key 10 is inserted into the key cylinder 24, and thereafter, the vehicle control circuit 150 causes the engine to start. As a result, the base portion 12B of the key body 12 and the transmitting element 18 are accommodated into the holder 76 and are embedded in the molten resin for molding the key knob 14 together with the holder 76. In the key knob 14 of the present embodiment, being different from a conventional key knob comprising a case which is divided into two pieces which are screwed each other, it is not necessary to effect a screwing. Accordingly, a cost for a screwing can be reduced from a total manufacturing cost. Further, the key knob 14 can be used at any number of times without forming any gag within the key knob 14. Therefore, the key knob 14 can be used for a long time without fearing that dust or water may enter into the key.

Claims: A key (10) having a built-in transmitting element (18), the key (10) comprising: a key body (12) having an insert portion (12A) and a base portion (12B); a hard resin holder (76) with a first accommodation portion (77) for accommodating the base portion (12B) of the key body (12), and with a second accommodation portion (78) for accommodating the transmitting element (18); the first accommodation portion (77) having a first engaging portion (67) for engaging an engaging portion of the base portion (12B) of the key body (12) such that the hard resin holder (76) is engaged with and secured to the base portion (12B) of the key body (12), wherein the first engaging portion (67) of the first accommodation portion (77) and an engaging portion (12H) of the base portion (12B) of the key body (12) are formed such that the key body (12) is accommodated in a predetermined position in the hard resin holder (76); and the second accommodation portion (78) having an insertion opening (63) for inserting the transmitting element (18), characterized in that the first accommodation portion (77) has an insertion opening (62) for inserting the base portion (12B) of the key body (12), that the insertion opening (62) of the first accommodation portion (77) and the insertion opening (63) of the second accommodation portion (78) are formed on a coplanar surface of the hard resin holder (76) and that an outer soft skin is formed on the hard resin holder (76) covering the insertion opening (63) of the second accommodation portion (78) of the hard resin holder (76) in order to reliably fix the transmitting element (18) in the hard resin holder (76). A key (10) having a built-in transmitting element (18) according to claim 1, wherein the hard resin holder (76) substantially seals the transmitting element (18) in the second accommodation portion (78). A key (10) having a built-in transmitting element (18) according to claim 1, wherein the outer soft skin is formed on at least a portion of the base portion (12B) of the key body (12). A key (10) having a built-in transmitting element (18) according to claim 1, wherein the predetermined position is a position such that the transmitting element (18) is spaced apart from the key body (12) by a predetermined distance. A key (10) having a built-in transmitting element (18) according to claim 1, wherein a first inserting direction in which the base portion (12B) of the key body (12) is inserted in the first accommodation portion (77) is opposite to an inserting direction in which the insertion portion (12A) of the key body (12) is inserted in a key cylinder. A key (10) having a built-in transmitting element (18) according to claim 1, wherein a first inserting direction in which the base portion (12B) of the key body (12) is inserted in the first accommodation portion (77) is the same as a second inserting direction in which the transmitting element (18) is inserted in the second accommodation portion (78) through the insertion opening (63). A key (10) having a built-in transmitting element (18) according to claim 1, wherein the second accommodation portion (78) has a second engaging portion (72) which engages the transmitting element (18) with the second accommodation portion (78) after inserting the transmitting element (18) through the insertion opening (63). A key (10) having a built-in transmitting element (18) according to claim 1, wherein the first engaging portion (67) of the first accommodation portion (77) is a convex shaped projection, and the engaging portion (12H) of the base portion (12B) of the key body (12) is a concave shaped recess which engages with the convex shaped projection (67). A key (10) having a built-in transmitting element (18) according to claim 7, wherein the second engaging portion (72) is a convex shaped projection.

Inventors: FUKUDA MASAKAZU, KATAGIRI TOSHIHARU, KITO SHOZO, OKAMURA NAOKATSU, SUGIYAMA HIROYUKI, FUKUDA, MASAKAZU, KATAGIRI, TOSHIHARU, KITO, SHOZO, OKAMURA, NAOKATSU, SUGIYAMA, HIROYUKI, FUKUDA, Masakazu, KK Tokai-Rika-Denki-Seisakusho, KATAGIRI, Toshiharu, KK Tokai-Denki-Seisakusho, KITO, Shozo, K.K. Tokai-Rika-Denki-Seisakusho, OKAMURA, Naokatsu, KK Tokai-Rika-Denki-Seisakusho, SUGIYAMA, Hiroyuki, KK Tokai-Rika-Denki-Seisakusho
Applicants: TOKAI RIKA CO LTD, KABUSHIKI KAISHA TOKAI-RIKA-DENKI-SEISAKUSHO
Application year: 1995
Main classification: E05B19
IPC codes: G07C9, E05B19