Invalidity dossier
US 5952916
Hammer-equipped emergency signal device
Current assignee: Atras Auto Co Ltd
Added 9/23/2026, 1:08:46 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview
Title: Hammer-equipped emergency signal device
Patent No.: US5952916A
Assignee: Atras Auto Co Ltd (original and current assignee per the source)
Inventor: Hideyasu Yamabe
Priority date: 1998-05-28 (priority to JP10146430A / JP2873001B2)
Filing date: 1998-12-17 (application US09/213,964)
Publication/grant date: 1999-09-14
Legal status: Expired – Fee Related; anticipated expiration 2018-12-17
Classifications include: B25D1/00 (hand hammers; hammer heads); B25D2250/271 (tools for breaking windows); B25D2250/295 (tools used in automobiles); B60Q3/46 (emergency lighting, e.g. escape routes)
Purpose: The source states the device is adapted to be installed chiefly in a car, for use in an emergency such as a traffic accident.
Plain-language scope (from the supplied text): A hollow main body has a grip of elliptic cross section and an enlarged head of circular cross section continuous with the grip. At least the grip is made of light-permeable material. A first light emitting body is housed in the grip to emit warning light through the grip; a second light emitting body is housed in the head to emit light through a disk-like light-permeable plate at the head's front end. A light emitting circuit, with a light emission controller for the first and second light emitting bodies and a battery in the grip, is housed in the main body. A control switch body turns the circuit off or on when the main body is placed in or removed from a car holder. Magnets are disposed around the outer periphery of the head's front end surface, and that outer periphery serves as a hammer portion for breaking glass. The main body may include an alarm buzzer sounding in correspondence to control-switch operation; the first light emitting body's light color is red; and a cutter's cutting edge is curved so as to be recessed toward the head.
Source: https://patents.google.com/patent/[US5952916](/patent/US5952916)/en
What the excerpt does not establish: It does not provide the full claims, the complete description, the number of figures, the dependent-claim scope, or the exact cut-off text of the enumerated arrangement (the excerpt truncates mid-sentence). No litigation, ownership transfers, validity, or prior-art analysis is provided or implied.
Generated 10/1/2026, 9:53:14 PM
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Litigation summary
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Proceedings on file (0)
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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