High temperature shut-off for an LCD heater

• US 6,891,129 B2
• Filed: 01/29/2004
• Issued: 05/10/2005
• Est. Priority Date: 12/11/2002
• Status: Expired due to Fees

• Current Assignee: Denso International America Incorporated (DENSO Corporation)
• Original Assignee: Denso International America Incorporated (DENSO Corporation)
• Inventors: Pala, Silviu, Arms, Christopher, Heflin, Scott
• Primary Examiner(s): Jeffery, John A.
• Application Number:
  US10/767,616
• Publication Number:
  US 20040182851A1
• Time in Patent Office: 467 Days
• Field of Search: 219/209, 219/494, 219/543, 219/544, 219/510, 219/517, 349/161
• US Class Current: 219/209
• CPC Class Codes: G02F 1/133382 Heating or cooling of liquid crystal cells other than for activation, e.g. circuits or arrangements for temperature control, stabilisation or uniform distribution over the cell
• CPC Class Codes: G02F 2201/36 Airflow channels, e.g. constructional arrangements facilitating the flow of air

Abstract

A main heater controller is adapted to control operation of the LCD heater. A temperature controlled override switch is adapted to disable the LCD heater, independent of the main heater controller, upon a temperature reaching a shut-off temperature above a normal operating temperature of the LCD. The temperature controlled switch has a current flow path made of a material whose conductivity is a function of temperature. A cavity in which the temperature controlled switch is located is also provided. The cavity is adapted to transfer heat in air emanating from the LCD heater to the temperature controlled switch. The housing which forms the cavity also includes a vent system for the cavity.

Claims

1. An LCD with a high temperature shut-off for an LCD heater to protect against run-away heating, comprising:

a main heater controller adapted to control operation of the LCD heater; and

a temperature controlled override switch adapted to disable the LCD heater, independent of the main heater controller, upon a temperature reaching a shut-off temperature; and

a housing surrounding an LCD panel and the LCD heater, and wherein the temperature controlled switch is located within a cavity of the housing, the cavity being adapted to transfer heat emanating from the LCD panel, the LCD heater, or both, to the temperature controlled switch, wherein the housing has a vent system for the cavity, wherein the housing has a slant portion slanted with respect to a vertical direction so that the heat is efficiently emanated from the LCD panel, the LCD heater, or both, to the temperature controlled switch.

2. An LCD according to claim 1, wherein the housing further has a portion slanted in a direction different from that of said slant portion.

3. An LCD with a high temperature shut-off for an LCD heater to protect against run-away heating, comprising:

a main heater controller adapted to control operation of the LCD heater; and

a temperature controlled override switch adapted to disable the LCD heater, independent of the main heater controller, upon a temperature reaching a shut-off temperature; and

a housing surrounding an LCD panel and the LCD heater, and wherein the temperature controlled switch is located within a cavity of the housing, the cavity being adapted to transfer heat emanating from the LCD panel, the LCD heater, or both, to the temperature controlled switch, wherein the housing has a vent system for the cavity, wherein the housing has a front-slant portion slanted toward a front portion of the liquid crystal display panel and a side-slant portion slanted toward a side portion of the liquid crystal display panel.

4. An LCD with a high temperature shut-off for an LCD heater to protect against run-away heating, comprising:

a main heater controller adapted to control operation of the LCD heater; and

a temperature controlled override switch adapted to disable the LCD heater, independent of the main heater controller, upon a temperature reaching a shut-off temperature; and

a housing surrounding an LCD panel and the LCD heater, and wherein the temperature controlled switch is located within a cavity of the housing, the cavity being adapted to transfer heat emanating from the LCD panel, the LCD heater, or both, to the temperature controlled switch, wherein the housing has a vent system for the cavity, further comprising a circuit board on which said temperature controlled switch is mounted, and a light emitting diode portion is formed, wherein said housing is attached to the circuit board at one end and covers the LCD panel at the other end.

5. An LCD according to claim 4, wherein said housing has a slant portion slanted from a portion close to the temperature controlled switch to the one end.

6. An LCD according to claim 5, wherein said the housing further has a portion slanted in a direction different from that of said slant portion.

7. An LCD according to claim 4, wherein the housing has a front-slant portion slanted toward a front portion of the liquid crystal display panel and a side-slant portion slanted toward a side portion of the liquid crystal display panel.