JP2013237363A - Vehicle seat control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle seat control device, capable of detecting whether or not an occupant is seated with high sensitivity and improving temperature rising performance of a heater, in a vehicle seat including the heater and an electrode for detection of seating.SOLUTION: A vehicle seat control device 1 includes: a heater 2 connected with a heater power supply circuit 21 through a heater connection switch 22; a seating detection circuit 31 for detecting seating of an occupant by an electrode 3 for detection; a state detection means 5 for detecting a state of a specified part of a vehicle; and a control part 4 which performs seating detection with a predetermined frequency by the seating detection circuit and electrically separates the heater from the heater power supply circuit by the heater connection switch at least in a period of seating detection. After it is detected that the occupant is seated while the heater is operated, the control part 4 decreases the frequency of the seating detection by the seating detection circuit while it is determined that seating is continued based on the state of the specified part detected by the state detection means 5.

Description

  The present invention relates to a vehicle seat control device, and more particularly to a vehicle seat control device that improves the seating detection performance of a passenger and the temperature rise performance of a heater in a vehicle seat having a heater and a seating detection electrode on a surface layer portion.

2. Description of the Related Art Conventionally, a seat heater that uses a heater on a seat surface portion or a backrest portion of an automobile seat to give heat to an occupant has been used. In such a seat heater, the temperature is adjusted by turning on / off the energization of the heater or changing the power supplied to the heater depending on the temperature.
In addition, a seating detection device that includes a sensor in an automobile seat and detects whether an occupant is seated in the seat is used. The deployment of the airbag is controlled by detection information from the seating detection device, such as not deploying the airbag when the occupant is not seated. Various methods are used to detect the seating of an occupant. As a typical example, a capacitive seating detection device is known. Since the human body is a dielectric, the impedance (capacitance) generated in the detection electrodes provided on the seat surface portion and the backrest portion of the seat is greatly different between when the occupant is seated and when the occupant is not seated. In addition, when an alternating electric field is generated around the detection electrode, the electric field is disturbed when an occupant is seated. Many seating detection devices detect the presence or absence of an occupant by measuring changes in these capacitance values or by measuring changes in the amount of electricity generated in the detection electrodes due to changes in capacitance. ing.

  Furthermore, an invention of a vehicle seat apparatus in which a vehicle seat is equipped with both a seat heater and a detection electrode for detecting whether or not seated is known (for example, see Patent Document 1). Further, an invention of a cloth material in which a seat heater and a detection electrode are integrally provided on a surface material of a vehicle seat is disclosed (see, for example, Patent Document 2).

JP 2008-24087 A JP 2011-239773 A

When the vehicle seat is equipped with a heater (heating element) and a seating detection electrode, both are made of a conductor and are disposed on the surface layer portion of the vehicle seat (seat surface or directly below it). Therefore, it is necessary to detect the seating of the occupant with high sensitivity using the detection electrode without impairing the heating performance of the heater. However, in the case where the presence or absence of the occupant is detected by detecting a change in the amount of electricity caused by a change in impedance (mainly capacitance) generated in the detection electrode, the gap between the heater and the detection electrode There is a problem that the detection sensitivity is lowered due to the generated capacitance.
Therefore, the vehicle seat device disclosed in Patent Document 1 uses a detection electrode disposed facing the seat heater to detect the presence / absence of an occupant with high sensitivity. The heater is set to a floating potential state during a period, and then the presence / absence of sitting is determined. Then, the presence / absence of a passenger seat is detected at a predetermined interval. According to this, since the heater is in a floating potential state when determining whether or not the occupant is seated, the electrostatic capacitance between the detection electrode and the heater is greatly reduced, and there is seating. It is said that the potential fluctuation range of the detection electrode when there is no occasion can be increased, and the detection sensitivity of passenger seating can be improved.
Further, in the cloth material described in Patent Document 2, a plurality of two types of conductive wire materials having different resistance values are provided, and the heater and the detection electrode are integrated. The two types of conductive wires are connected in parallel and used by switching between a heater mode that functions as a heater and a sensor mode that functions as a seating detection electrode by separating the heater. According to this cloth material, it is said that by increasing the number of high-resistance conductive wires that act as detection electrodes, the detection sensitivity in the sensor mode can be increased and the overall power consumption can be suppressed.
However, in any of the above-mentioned conventional examples, it is necessary to detect the seating of the occupant at regular time intervals. Therefore, power cannot be supplied to the heater at least during the seating detection period, and the temperature rise performance of the heater is reduced. There was a problem of doing.

  In view of the above-described problems, the present invention can detect presence / absence of an occupant with high sensitivity in a vehicle seat having a heater and a seating detection electrode on the surface layer portion, and improve the temperature rise performance of the heater. An object of the present invention is to provide a vehicle seat control device.

In order to solve the above problems, the vehicle seat control device according to the first aspect of the present invention is provided on the surface layer portion of the vehicle seat and connected to the heater power supply circuit via the heater connection switch, and the surface layer portion of the vehicle seat. A seating detection circuit for detecting the seating of an occupant by a detection electrode provided on the vehicle, state detection means for detecting the state of a predetermined part of the vehicle, and seating detection at a predetermined frequency by the seating detection circuit, at least The seating detection period includes a control unit that electrically disconnects the heater and the heater power supply circuit by the heater connection switch, and the control unit has the heater activated and an occupant is seated. After detecting this, while it is determined that the seating is continued based on the state of the predetermined part detected by the state detecting means, the seating detection circuit frequently detects seating. And summarized in that lowering.
According to a second aspect of the present invention, in the first aspect, the state of the predetermined part of the vehicle includes one or more of a vehicle speed, a position of a shift lever, whether a seat belt is attached, whether a door is locked, and whether a door is opened or closed. The gist.
The gist of the third invention is that, in the first or second invention, the heater connection switch is configured by connecting a plurality of semiconductor switch elements in series.
The gist of the fourth invention is that, in the first to third inventions, the heater and the detection electrode are integrally formed using a conductive member.

  According to the vehicle seat control device of the first aspect of the present invention, a heater connected to the heater power supply circuit via the heater connection switch, a seating detection circuit for detecting the seating of the occupant by the detection electrode, and a predetermined part of the vehicle Control for detecting seating at a predetermined frequency by the state detection means for detecting the state of the head and the seating detection circuit, and at least during the seating detection period, the heater connection switch electrically disconnects the heater and the heater power supply circuit. Therefore, the presence or absence of seating can be detected with high sensitivity by disconnecting the heater from the heater power supply circuit during the period when seating detection of the occupant is performed. In addition, after detecting that the heater is operated and the occupant is seated, the control unit determines that the seating is continued based on the state of the predetermined portion detected by the state detection unit. In order to reduce the frequency of seating detection by the seating detection circuit, when the heater is turned on, for example, when the heater is turned on, It is not necessary to perform seating detection, and the interruption period of power supply to the heater can be greatly reduced. Thereby, it becomes possible to fully demonstrate the temperature rising performance of a heater. Further, when the control unit detects the state of the predetermined part by the state detection unit and determines that there is a possibility that the seating is not continued, the control unit can immediately perform the seating detection using the seating detection circuit. . For this reason, while it is determined that the seating is continued, the seating detection using the seating detection circuit is not performed, and the heating of the seat by the heater can be maximized.

  When the state of the predetermined part of the vehicle includes one or more of the vehicle speed, the position of the shift lever, the presence / absence of the seat belt, the presence / absence of the door lock, and the door opening / closing, the control unit is running or stopped By detecting the state of each part of the vehicle, it is possible to make a highly accurate determination as to whether or not the seated state of the occupant continues. It is also possible to control the heater to stop when the passenger forgets to turn off the heater switch and leaves.

  When the heater connection switch is configured by connecting a plurality of semiconductor switch elements in series, an increase in electrostatic capacitance due to the parasitic capacitance of the semiconductor switch element is suppressed, and the seating detection circuit increases sensitivity. The presence or absence of seating can be detected. Moreover, since it does not have a mechanical contact, it can be set as the vehicle seat control apparatus excellent in reliability and durability.

  When the heater and the detection electrode are integrally formed using a conductive member, a vehicle seat control device can be realized with a very simple configuration.

The present invention will be further described in the following detailed description with reference to the drawings referred to, with reference to non-limiting examples of exemplary embodiments according to the present invention. Similar parts are shown throughout the several figures.
It is a typical block diagram showing the structure of the vehicle seat control apparatus which concerns on this embodiment. It is a typical block diagram showing the structure of the vehicle seat control apparatus in case a heater and a detection electrode are provided as separate bodies. It is a typical block diagram showing the structure of a vehicle seat control apparatus in case a heater and the electrode for a detection are provided in common or integrally. It is a block diagram for demonstrating the heater connection switch comprised by connecting a some semiconductor switch element in series. It is a schematic diagram showing the example which forms a heater and the electrode for a detection integrally using a different electrically-conductive member. It is a timing chart for demonstrating operation | movement of a vehicle seat control apparatus. It is a flowchart showing the example of the control method in a vehicle seat control apparatus. It is a flowchart which shows the example of the method of detecting a predetermined vehicle state and judging whether seating is continued.

  The items shown here are for illustrative purposes and exemplary embodiments of the present invention, and are the most effective and easy-to-understand explanations of the principles and conceptual features of the present invention. It is stated for the purpose of providing what seems to be. In this respect, it is not intended to illustrate the structural details of the present invention beyond what is necessary for a fundamental understanding of the present invention. It will be clear to those skilled in the art how it is actually implemented.

(Configuration of vehicle seat control device)
A vehicle seat control device according to this embodiment includes a heater for warming an occupant seated in a vehicle seat and a detection electrode for detecting whether or not the occupant is seated (seating detection). Applied to the sheet. The vehicle seat is not particularly limited as long as it is a seat on which an occupant is seated, such as a driver's seat, a passenger seat, and a rear seat of an automobile. The heater and the detection electrode are usually disposed on the surface layer of the vehicle seat.
The surface layer portion of the vehicle seat is intended to be the surface of the vehicle seat or a portion immediately below the vehicle seat. In addition to the skin material of the vehicle seat, a seat cover and a seat provided so as to cover the outer surface of the seat integrally with the seat Includes between cover and cushioning material. Regardless of whether it is a seating portion or a backrest portion of the vehicle seat, the heater and the detection electrode may be embedded in the surface layer portion of the vehicle seat, or may be formed integrally with a member constituting the surface layer portion. Also good. Further, the heater and the detection electrode may be provided in common or integrally.

  FIG. 1 shows a configuration of a vehicle seat 7 on which an occupant 9 is seated and a vehicle seat control device 1 according to the present embodiment. The seat 7 includes a seating portion 71 and a backrest portion 72, and is fixed to the floor portion 8 of the vehicle body by a seat frame 81. The vehicle body 8 can be electrically grounded (vehicle ground). If the seat frame 81 is made of metal, the seat frame 81 can be used as a ground electrode. The interior of the seat seating portion 71 is configured by a cushion pad made of urethane foam or the like, a seat cover, etc. disposed on a seat frame 81, and the surface is covered with a surface material such as a woven fabric. Yes. Similarly, the backrest 72 is composed of a seat frame, a cushion material, a surface material, and the like.

  The vehicle seat control device 1 is provided on the surface layer portion of the vehicle seat 7, the heater 2 connected to the heater power supply circuit 21 via the heater connection switch 22, and the detection electrode 3 provided on the surface layer portion of the vehicle seat 7. The seat detection circuit 31 for detecting the seating of an occupant, the state detection means 5 for detecting the state (51, 52,...) Of a predetermined part of the vehicle, and the seating detection circuit 31 detect the seating, and at least the seating detection. During this period, the control unit 4 that electrically separates the heater 2 and the heater power supply circuit 21 by the heater connection switch 22 is provided. Then, after detecting that the seat heater is activated and the occupant 9 is seated, the control unit 4 is based on the state (51, 52,...) Of the predetermined part detected by the state detection means 5. While it is determined that the seating continues, the seating detection circuit 31 is configured to reduce the frequency of seating detection.

The heater 2 is made of a conductive material that generates heat when energized. The number, shape, size, arrangement, etc. of the heater are not particularly limited. In this example, one heater 2 is provided on the seat surface layer of the seat 71 that contacts the body of the seated person. A plurality of heaters 2 may be provided separately, or may be provided on the backrest 72 in addition to the seating. The material and structure of the heater 2 are not particularly limited, and for example, a resistance heating wire or a planar heating element can be used.
The heater 2 is electrically connected to the heater power supply circuit 21 via the heater connection switch 22. The type and configuration of the heater connection switch 22 are not particularly limited, and a semiconductor switch element or a relay or the like may be used. On / off of the heater connection switch 22 is controlled by the control unit 4. When the heater connection switch 22 is off, the heater 2 is electrically disconnected from the heater power supply circuit 21.

  The heater power supply circuit 21 is a circuit that receives power from a vehicle battery (not shown) and supplies power to the heater 2. The amount of heat generated by the heater 2 varies depending on the amount of power supplied from the heater power supply circuit 21. The method for controlling the amount of heat generated by the heater 2 is not particularly limited, and may be, for example, on / off control of supply voltage or current, current control by PWM, or the like. You may comprise so that the emitted-heat amount of the heater 2 may be controlled by the control part 4. FIG.

  Usually, the seat heater is provided with a heater switch or the like (not shown) for an occupant to turn the seat heater on and off and adjust its temperature. The vehicle seat control device 1 can be configured to allow the heater 2 to be energized (activate the heater) when the heater switch is on.

The detection electrode 3 serves as an electrode for detecting the seating of an occupant. The shape, size, arrangement, etc. of the detection electrode 3 are not particularly limited. In FIG. 1, the detection electrode 3 is provided so as to face the lower side of the heater 2. However, the detection electrode 3 is not limited thereto, and may be arranged side by side with the heater 2. Any structure that does not hinder heat transfer to the person may be disposed on the seat surface side of the heater 2. Further, the heater 2 and the detection electrode 3 can be integrated and used as the heater 2 and the detection electrode 3 in common.
It is sufficient that at least one detection electrode 3 is provided. The detection electrode 3 may be provided at the seating portion and the backrest portion, but is preferably provided at least at the seating portion 71. The detection electrode 3 may be matched to the size or shape of the seating portion or the backrest portion of the seat, or the electrode may be provided only in a portion where the occupant's body contacts when seated. Alternatively, a plurality of electrodes may be arranged as the detection electrode 3 and electrically connected to each other.

A wide range of materials can be used for the detection electrode 3 as long as it is a conductive material. For example, the detection electrode 3 can be configured using a metal wire, a conductive cloth, a conductive film, a metal plate, or the like.
Examples of the conductive cloth include a woven cloth appropriately woven with conductive fibers such as stainless steel wires, carbon fibers, and plated fibers. For example, if a woven fabric in which conductive fibers such as stainless wire are woven at intervals of about 1 to 10 mm is used, a detection electrode having excellent durability and economy can be realized. The conductive cloth can also be applied as the heater 2. By using the conductive cloth for the heater 2 and the detection electrode 3, their arrangement, shape, dimensions, etc. can be designed arbitrarily, and can also be formed integrally with the surface material constituting the other part of the sheet become. Further, the air permeability is not lowered by the heater 2 or the detection electrode 3, and the texture of the sheet is not impaired.

  The seating detection circuit 31 is connected to the detection electrode 3 and is a circuit for detecting seating of an occupant. Various known methods can be used for seating detection. For example, when the occupant 9 is seated on the seat 7, the human body has a relative dielectric constant larger than that of air, and therefore there is a capacitance between the detection electrode 3 and the vehicle body 81 (ground electrode) due to the human body. As a result, the capacitance between the electrodes increases as compared with the case where the passenger is not seated. For this reason, when an AC signal (for example, a signal having a constant frequency in the range of several tens of kHz to several hundreds of kHz, preferably 70 kHz to 200 kHz) is supplied from the seating detection circuit 31 to the detection electrode 3, detection is performed depending on whether the passenger is seated. The voltage, current, phase, and the like of the signal detected by the electrode 3 changes, and the amount of change can be measured by the seating detection circuit 31. The control unit 4 is configured to perform seating detection using the seating detection circuit 31.

The state detection means 5 is means for detecting the state of a predetermined part of the vehicle. Here, the state of the predetermined part of the vehicle is information useful for determining whether or not the seated state of the passenger on the seat is continued, that is, whether or not the seated state may have changed. Intended. The state (51, 52,...) Of the predetermined part includes, for example, vehicle speed, shift lever position, seat belt attachment / non-existence, door lock / non-existence, door opening / closing, etc., including one or more of these. It can be used for the above judgment.
The state detection unit 5 can be configured on the control unit 4. The state detection means 5 may be configured to detect a state for each predetermined part by a sensor, or may be configured to receive information on the state from an external device.

  The controller 4 is configured to detect the seating of an occupant by the seating detection circuit 31, detect the state of a predetermined part of the vehicle by the state detection means 5, and control the heater connection switch 22. In addition, it can be configured to be connected to the heater power supply circuit 21 and to control the power supplied to the heater 2. Further, the result of detection of the seating of the occupant can be output and used for controlling the deployment of the airbag.

  The control part 4 can be comprised by a microcontroller (microcomputer) and a peripheral circuit, for example. The microcontroller can include a program for measurement, control, determination, and the like performed by the vehicle seat control device 1. Further, the control unit 4 can store parameters for seating determination, conditions for determining whether the seating state is continued from the state of a predetermined part of the vehicle, and the like.

  FIG. 2 shows a connection in the case where the heater 2 and the detection electrode 3 are respectively provided on the surface layer portion of the sheet 7. This is a case where the heater 2 and the detection electrode 3 constitute separate electric circuits, and it does not matter whether the heater 2 and the detection electrode 3 are formed separately or integrally. In this case, when the heater connection switch 22 is turned off (disconnected) by the control unit 4, the heater 2 becomes a floating potential. Therefore, a change in potential due to the seating of the occupant is detected by the seating detection circuit 31 connected to the detection electrode 3. It can be detected with high sensitivity.

  FIG. 3 shows a configuration in which the heater 2 and the detection electrode 3 are configured as a common conductor portion 20 and are provided on the surface layer portion of the sheet 7. In this case, when the heater connection switch 22 is turned off (disconnected) by the control unit 4, the conductor unit 20 is disconnected from the heater power supply circuit 21 and the reference potential and is connected only to the seating detection circuit 31. The change in potential due to can be detected with high sensitivity by the seating detection circuit 31 connected to the conductor portion 20.

FIG. 4 is a diagram illustrating an example in which the heater connection switch 22 is configured by an FET (MOS FET). A source S and drain D of adjacent FETs are connected, and a plurality of FETs (22a1 to 22an, 22b1 to 22bn) are connected in series to constitute the heater connection switch 22. By controlling the potential of the gate G by the control unit 4, the heater connection switch 22 can be turned on / off.
In general, since the semiconductor switch element has a large parasitic capacitance, if the heater connection switch 22 is configured by a semiconductor switch element, the detection of the parasitic capacitance of the semiconductor switch element in the seating detection for detecting the change in the amount of electricity caused by the change in the capacitance. There is a problem that the influence cannot be ignored. However, by configuring the heater connection switch 22 by connecting a plurality of semiconductor switch elements in series, it is possible to reduce the capacitance caused by the parasitic capacitance of the semiconductor switch elements and make the seating detection circuit 31 highly sensitive. Therefore, the presence / absence of sitting can be detected more accurately. Moreover, since the semiconductor switch element does not have a mechanical contact, reliability and durability can be improved.

  The heater 2 and the detection electrode 3 can be integrally formed using a conductive member. For example, FIG. 5 schematically shows a conductor portion 20 in which the heater 2 and the detection electrode 3 are integrally formed. The conductor part 20 includes a plurality of conductive wire rods (first conductive members) 201 provided in parallel on one plane and a plurality of conductive wire rods (first conductive members) provided in parallel on the same plane. 2 conductive members) 202. Both ends of the first conductive member 201 and the second conductive member 202 are electrically connected by conductive members 203A and 203B. Then, lead wires 204A and 204B are led out from the conductive members 203A and 203B as connection terminals of the conductor portion 20 (common to the heater 2 and the detection electrode 3). As shown in FIG. 3, the conductor portion 20 configured in this way can be connected to the heater connection switch 22 and the seating detection circuit 31.

  Here, the resistance value of the second conductive member 202 is higher than the resistance value of the first conductive member 201 (for example, about ten times the resistance value of the first conductive member 201). Thus, when functioning as a heater, heat can be generated mainly by the current flowing through the first conductive member 201 having a low resistance. Further, by increasing the number of high-resistance second conductive members 202, the sensitivity when functioning as a detection electrode can be improved, and when the entire structure is formed using only the first conductive member 201. In comparison, low power consumption can be achieved. In this example, the two second conductive members 202 are arranged between the first conductive members 201, but the interval and the number of the conductive members can be set as appropriate. The conductor portion 20 can be formed by a method such as weaving a first conductive member 201 and a second conductive member 202 made of a metal wire, conductive fiber, or the like into a cloth.

(Operation of vehicle seat control device)
FIG. 6 is a timing chart for explaining the operation of the vehicle seat control apparatus 1. FIG. 4A shows the state of the heater switch. For example, when the heater switch is turned on by an occupant, the heater is activated. FIG. 2B shows the electric power P supplied to the heater 2. The set value and control method of the supplied power P are not particularly limited. FIG. 4C shows the state of the heater connection switch 22 controlled by the control unit 4. When the heater 2 is on, the heater 2 is connected to the heater power supply circuit 21, and the heater 2 can be energized. When the heater connection switch 22 is off, the heater 2 is electrically disconnected from the heater power supply circuit 21.

  FIG. 6D shows the seating detection operation by the detection electrode 3. At least during the seating detection period Td, the seating detection circuit 31 applies an AC voltage to the detection electrode 3 and measures a change in impedance or the like generated in the detection electrode 3. FIG. 4E shows the detection result by the seating detection circuit 31. When the logic is “1”, the seating is present, and when the logic is “0”, the seating is absent. FIG. 5F shows the detection result of the vehicle speed as an example of the vehicle state. When the logic is “1”, the vehicle speed is equal to or higher than a predetermined value, and when it is “0”, the vehicle speed is lower than the predetermined value. ing.

While the heater switch is off, as shown in FIG. 6D, the control unit 4 detects the presence or absence of the occupant by the seating detection circuit 31 at a certain frequency (cycle T1). The period T1 can be set to, for example, 1 second to several seconds. The control unit 4 can keep the heater connection switch 22 off while the heater switch is off.
When the heater switch is turned on, the control unit 4 controls the heater connection switch 22 to be turned on so that electric power is supplied to the heater 2. The supply of electric power to the heater 2 may be started when the seating of an occupant is detected. Moreover, the seating detection is continuously performed by the control unit 4 every cycle T1. At least during seating detection, the control unit 4 controls the heater connection switch 22 to be turned off to electrically disconnect the heater 2. After the occupant's seating is detected (t1 in the figure), the frequency of seating detection by the seating detection circuit 31 can be reduced by monitoring the state of a predetermined part of the vehicle such as the vehicle speed. As a result, the frequency with which the heater connection switch 22 is turned off decreases, so that the temperature rise by the heater 2 can be prevented.

For example, when the target seat is a driver's seat, it can be determined that the occupant is seated if the vehicle is traveling beyond a certain speed after the occupant is seated. When it is determined that the occupant continues to be seated, the control unit 4 lowers the frequency of seating detection by the seating detection circuit 31 (longens the period T2 for seating detection) or performs seating detection. Or not. Further, when the control unit 4 monitors the state of a predetermined part of the vehicle and determines that there is a possibility that the seating of the occupant is not continued, the seating detection circuit 31 performs seating detection. be able to. For example, when the vehicle speed drops below a certain value (t2 in the figure), seating detection can be performed.
Moreover, since the presence or absence of the seat and the vehicle state are monitored by the control unit 4, it is possible to perform control such that the operation of the heater 2 is stopped when the occupant forgets to turn off the heater switch and leaves the seat.

(Control method of vehicle seat control device)
In the vehicle seat control device 1, for example, a control method as shown in FIG. This control process is mainly executed by the control unit 4.
The vehicle seat control device 1 can repeatedly perform the following control while the ignition switch of the vehicle is turned on, for example (S10).

First, in order to detect whether a passenger is seated, the heater 2 and the heater power supply circuit 21 are separated by the heater connection switch 22 (S20). Then, the amount of electricity generated in the detection electrode 3 is measured by the seating detection circuit 31 (S22). The presence / absence of seating is determined based on the measured value (S24). If it is determined that there is no seating, control is performed so that the airbag cannot be deployed (S28), and seating detection is performed again (S20-24). Repeat to do. Here, the period T1 for repeating the seating detection may be set arbitrarily.
If it is determined in step S24 that "sitting is present", control is performed so that the airbag can be deployed (S26), and the process proceeds to the following steps.

If an occupant is seated, the state of the heater switch is determined (S30). When the heater switch is off, the energization is stopped when the heater 2 is energized (S34), and the seating detection is repeated (S20 to 24).
If the heater switch is on, the heater connection switch 22 connects the heater 2 and the heater power supply circuit 21 to supply power to the heater 2 (S32).

  Next, the state of a predetermined part of the vehicle is detected (S40). For this purpose, the state of the predetermined part may be detected by a sensor, or information indicating the state of the predetermined part may be acquired from another device. Then, based on the detected vehicle state, it is determined whether or not the occupant has been seated (that is, there is a possibility that the occupant has not been seated) (S42). This criterion can be stored in advance in the memory in the control unit 4 in correspondence with the state of each part. If it is determined in step S42 that there is a possibility that the user is not seated, control is performed so as to perform seating detection (S20 to S24). On the other hand, if it is determined that there is no possibility of non-seating, that is, it is determined that the seating is continued, the elapse of a predetermined time T2 longer than when the heater is not operating (S50), and seating detection is performed. Repeat (S20-24). Alternatively, the predetermined vehicle state monitoring (S40, S42) may be repeatedly performed, and control may be performed so that seating detection (S20 to 24) is not performed until it is determined that there is a possibility that the vehicle is not seated. .

FIG. 8 shows a specific example of detection of the predetermined part state of the vehicle (S40) and determination based on the detection (S42). In this example, the vehicle speed, the position of the shift lever, the presence / absence of a seat belt, the presence / absence of a door lock, and the door opening / closing are cited as the state of a predetermined part of the vehicle.
If the target vehicle seat is the driver's seat, it is detected that the occupant is seated, and then the vehicle speed is acquired, and it is determined whether the seating is continued based on the value (S401). If the vehicle speed exceeds a predetermined value (for example, 10 km / hour), it can be determined that there is a high possibility of sitting (S411). On the other hand, if the vehicle speed is equal to or lower than the predetermined value, the following vehicle states are sequentially determined.

When the position of the shift lever (S402) is “P”, the seat belt (S403) is not attached, the door lock (S404) is released, and the door (S405) is opened Then, it is determined that there is a possibility of non-seating (sitting is not continued) (S410). As a result, the control unit 4 can perform seating detection (S20 to S24 in FIG. 7).
On the other hand, if any of the states is different from the above, it is determined that the seating is likely to be continued (S411). As a result, the control unit 4 may perform seating detection (S20 to S24) after a predetermined time T2 has elapsed, or after monitoring the vehicle state and determining that there is a possibility of non-sitting. You may make it perform seating detection.
Note that FIG. 8 is merely an example of determining whether or not seating is continued based on the state of each part of the vehicle, and a part to be detected and a determination method based on the state may be appropriately set.

  The present invention is not limited to the embodiment described above, and various modifications can be made within the scope of the present invention depending on the purpose and application.

  DESCRIPTION OF SYMBOLS 1; Vehicle seat control apparatus, 2; Heater, 21; Heater power supply circuit, 22; Heater connection switch, 3; Detection electrode, 31; Seating detection circuit, 4: Control part, 5: State detection means, 51, 52; 7: vehicle seat, 71; seating portion, 72; backrest portion, 8; vehicle body, 81; seat frame (ground potential), 9; human body.

Claims (4)

A heater provided on a surface layer portion of a vehicle seat and connected to a heater power supply circuit via a heater connection switch;
A seating detection circuit for detecting the seating of an occupant by a detection electrode provided on a surface layer portion of the vehicle seat;
State detecting means for detecting the state of a predetermined part of the vehicle;
The seating detection circuit performs seating detection at a predetermined frequency, and at least during the seating detection period, a control unit that electrically disconnects the heater and the heater power supply circuit by the heater connection switch;
With
While the control unit detects that the heater is operated and the occupant is seated, the control unit determines that the seating is continued based on the state of the predetermined portion detected by the state detection unit. A vehicle seat control device that reduces the frequency of seating detection by the seating detection circuit.   The vehicle seat control device according to claim 1, wherein the state of the predetermined part of the vehicle includes one or more of a vehicle speed, a position of a shift lever, whether or not a seat belt is attached, whether or not a door is locked, and door opening and closing.   The vehicle seat control device according to claim 1, wherein the heater connection switch is configured by connecting a plurality of semiconductor switch elements in series.   4. The vehicle seat control device according to claim 1, wherein the heater and the detection electrode are integrally formed using a conductive member. 5.

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