HEATER AND HEATING SYSTEM

• US 20130127212A1
• Filed: 07/27/2011
• Published: 05/23/2013
• Est. Priority Date: 08/05/2010
• Status: Active Grant

• Current Assignee: Joyson Safety Systems Japan GK
• Original Assignee: Takata Corporation (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Aoki, Hiroshi
• Granted Patent: US 9,132,758 B2
• Time in Patent Office: Days
• US Class Current: 297/180.12
• CPC Class Codes: B60N 2/002 Seats provided with an occupancy detection means mounted therein or thereon detection means responsive to presence or absence of children B60N2/266
• CPC Class Codes: B60N 2/5685 Resistance

Abstract

Heater electrodes and a sensor electrode both in a film shape are formed on the top surface of an insulation sheet without overlapping with each other. As a result, a seat heater has a small overall thickness. Then, the seat heater can be placed near the seating surface of a seat without making the seat less comfortable to sit in. The occupant is detected based on the impedance between the sensor electrode and the vehicle. As a result, it is possible to warm the occupant seated on the seat efficiently and detect the occupant with accuracy.

Claims

1. A heater for warming an occupant seated on a seat of a vehicle, the heater comprising:

a heating element disposed in the seat;

heater electrodes connected to the heating element; and

a sensor electrode disposed in the seat,

wherein the heater electrodes are supplied with electric power to the heating element,

the impedance between the sensor electrode and vehicle varies depending on the presence of the occupant in the seat, and

the heater electrodes and sensor electrode are placed in the same plane.

2. The heater according to claim 1, wherein the heater electrodes and sensor electrode are in a film shape.

3. A heating system for warming an occupant seated on a seat of a vehicle, the heating system comprising:

the heater according to claim 1;

a supply unit that is connected to the heater electrodes and supplies electric power to the heating element;

a measurement unit that measures the impedance between the sensor electrode and vehicle; and

a detection unit that detects the occupant seated on the seat based on the impedance measured by the measurement unit.

4. The heating system according to claim 3, wherein:

the measurement unit measures the capacitance between the sensor electrode and vehicle as an impedance correlation value from the AC voltage applied between the sensor electrode and vehicle and the current or voltage input to the sensor electrode in response to change in the impedance.

5. The heating system according to claim 4, wherein:

the measurement unit measures the quadrature component of the current at the AC voltage as the capacitance as an impedance correlation value.

6. The heating system according to claim 5, wherein:

the measurement unit measures the in-phase component of the current at the AC voltage, and

the detection unit detects the occupant seated on the seat from the result of comparison between a threshold defined based on a relationship between the in-phase component and quadrature component and the capacitance.

7. The heating system according to claim 6, comprising:

a temperature detection sensor detecting the temperature of the seat near the heating element,

wherein the detection unit detects the occupant from the temperature of the seat detected by the temperature detection sensor and the result of comparison between the threshold and capacitance.

8. The heating system according to claim 3, comprising:

a switching unit that periodically connects the supply unit and heater electrodes,

wherein the measurement unit measures the impedance when the supply unit and heater electrodes are disconnected.

9. The heating system according to claim 8, wherein the switching unit connects the heater electrodes to the supply unit and to the power source applying a voltage to the heater electrodes alternately.

10. The heating system according to claim 9, wherein the power source applies a voltage equal in phase to the voltage applied to the sensor electrode.

11. The heating system according to claim 9, wherein the power source applies a voltage different in phase from the voltage applied to the sensor electrode.

12. The heating system according to claim 3, comprising:

a switching unit that periodically connects the supply unit and heater electrodes,

wherein the measurement unit detects the occupant from the result of comparison of the impedance between when the supply unit and heater electrodes are connected and when the supply unit and heater electrodes are disconnected.

13. The heating system according to claim 12, wherein:

the heater electrodes are connected to the supply unit and to the power source applying a voltage to the heater electrodes alternately, and

the impedance is measured when a voltage equal in phase to the voltage applied to the sensor electrode is applied to the heater electrodes.

14. The heating system according to claim 12, wherein:

the heater electrodes are connected to the supply unit and to the power source applying a voltage to the heater electrodes alternately, and

the impedance is measured when a voltage different in phase from the voltage applied to the sensor electrode is applied to the heater electrodes.

15. A heating system for warming an occupant seated on a seat of a vehicle, the heating system comprising:

the heater according to claim 2;

a supply unit that is connected to the heater electrodes and supplies electric power to the heating element;

a measurement unit that measures the impedance between the sensor electrode and vehicle; and

a detection unit that detects the occupant seated on the seat based on the impedance measured by the measurement unit.

16. The heating system according to claim 15, comprising:

a switching unit that periodically connects the supply unit and heater electrodes,

wherein the measurement unit measures the impedance when the supply unit and heater electrodes are disconnected.