Portable transmitter contained in a hard-to-open case

• US 20040201451A1
• Filed: 04/06/2004
• Published: 10/14/2004
• Est. Priority Date: 04/10/2003
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Sugimoto, Keiichi, Nakagawa, Mitsuru
• Granted Patent: US 7,242,278 B2
• Time in Patent Office: Days
• US Class Current: 340/5.62
• CPC Class Codes: B60R 25/406 Power supply in the remote key
• CPC Class Codes: G07C 2009/00952 Electronic keys comprising a mechanical key within their housing, e.g. extractable or retractable emergency key
• CPC Class Codes: G07C 9/00944 Details of construction or manufacture

Abstract

An ID code is wirelessly sent to a device, such as a keyless-entry system or a keyless-starter system mounted on an automobile, from a portable transmitter. Electronic components including an electronic circuit board, a transponder and a battery are all contained in a resin case. The resin case is composed of a front case and a rear case, both firmly connected to each other. The case cannot be opened to take away the transponder contained therein without breaking the case. If the case is forcibly opened, a trace showing such a fact is unavoidably left on the case. The battery contained in the case, however, can be replaced or unloaded without breaking the case through an opening formed exclusively for the battery.

Claims

1. A portable transmitter comprising:

a transponder for transmitting an ID code to a device, the ID code allowing the device to operate; and

a case containing the transponder therein, wherein;

the case comprises a front case and a rear case, both cases firmly engaging with each other not to be separated without breaking the case.

2. The portable transmitter as in claim 1, wherein:

the front case includes a front hook, and the rear case includes a rear hook that engages with the front hook.

3. The portable transmitter as in claim 2, wherein:

a projection is formed in either the front hook or the rear hook;

a depressing is formed in either the front hook or the rear hook in which the projection is not formed; and

the projection engages with the depression thereby firmly connecting the front case and the rear case together.

4. The portable transmitter as in claim 2, wherein:

a projection and a depression are formed in both the front hook and the rear hook; and

the projection formed in the front hook engages with the depression formed in the rear hook; and

the projection formed in the rear hook engages with the depression formed in the front hook, thereby firmly connecting the front case to the rear case.

5. The portable transmitter as in claim 3, wherein:

both of the front case and the rear case are formed by molding a resin material;

a first seal member is disposed between the front case and the rear case to keep the case water-tight; and

the depression is formed by a slidable core having a projected portion corresponding to the depression, and a sealing surface of the front case contacting the first seal member is formed by a core other than the slidable core.

6. The portable transmitter as in claim 4, wherein:

both of the front case and the rear case are formed by molding a resin material;

a first seal member is disposed between the front case and the rear case to keep the case water-tight; and

the depression is formed by a slidable core having a projected portion corresponding to the depression, and a sealing surface of the front case contacting the first seal member is formed by a core other than the slidable core.

7. The portable transmitter as in claim 2, wherein:

either one of the front hook or the rear hook is made easier to break when a force to forcibly separate the front case from the rear case is applied than the other hook.

8. The portable transmitter as in claim 2, further including a battery contained in the case, wherein:

the case includes an opening for loading or unloading the battery therethrough and a removable battery cover for closing the opening.

9. The portable transmitter as in claim 8, wherein:

a second seal member is disposed around the opening to keep water-tight a portion where the battery cover contacts the case.

10. The portable transmitter as in claim 8, wherein:

a wall separating the transponder from the battery is formed in the case.

11. The portable transmitter as in claim 8, further including an electronic circuit board powered by the battery for transmitting the same ID code as the ID code to be transmitted from the transponder, wherein:

the ID code is transmitted from the electronic circuit board to allow the device to operate under a normal condition where a voltage of the battery is higher than a predetermined level, and the ID code is transmitted from the transponder to allow the device to operate under an abnormal condition where the voltage of the battery is lower than the predetermined level.