JP7048882B2 - Vehicle seat - Google Patents

Description

The present invention relates to a vehicle seat provided with a heater capable of heating the seat surface.

Conventionally, a vehicle seat provided with a heater and a control device for controlling the heater is known (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2017-157279

By the way, in a vehicle seat provided with a heater, it is desired to connect a thermostat to the heater so as to prevent an excessive current from flowing through the heater and mechanically cut off the energization of the heater. However, when a plurality of heaters are provided on the vehicle seat, each heater must be individually provided with a thermostat, which causes a problem of high cost.

Therefore, an object of the present invention is to reduce the number of thermostats in a vehicle seat provided with a plurality of heaters to reduce the cost.

The present invention for solving the above-mentioned problems is a vehicle seat provided with a seat cushion and a seat back, the first heater for heating the first region of the seat cushion and the seat back, and the seat cushion. A second heater for heating a second region of the seat back, which is different from the first region, and a thermostat for shutting off the energization are provided.
The first heater and the second heater are configured to be independently controllable, and the thermostat is connected to the ground side with respect to the first heater and the second heater.

According to this, since it is only necessary to provide one thermostat for a plurality of heaters, it is possible to reduce the cost.

Further, the connecting portion between the first heater and the second heater and the thermostat may be sandwiched between sheet-shaped supports.

According to this, it is possible to prevent the connection portion between each heater and the thermostat from being short-circuited to the ground.

Further, the vehicle seat may include a thermistor for detecting the temperature of the first heater.

Further, the vehicle seat includes a control device for controlling energization of the first heater and the second heater, and the control device is the first heater or the first heater based on a signal detected by the thermistor. 2 The heater may be configured to stop energization.

According to this, when an excessive current is about to flow in the first heater, the energization can be stopped by the control device based on the signal detected by the thermistor without operating the thermostat.

Further, the seat cushion and the seat back may have a contact portion in contact with each other, and the thermostat may be arranged so as to overlap the center position in the front-rear direction of the contact portion.

According to this, the thermostat arranged on the ground side can be protected by being sandwiched between the seat cushion and the seat back.

Further, the seat cushion and the seat back have contact portions that come into contact with each other, and the thermostat may be arranged so that the center position of the thermostat in the front-rear direction overlaps with the contact portion.

According to this, the thermostat arranged on the ground side can be protected by being sandwiched between the seat cushion and the seat back.

Further, the vehicle seat includes a control device for controlling energization of the first heater and the second heater, and the control device sets the energization period per unit time to provide the first heater and the second heater. It is possible to execute PWM control that controls the current supplied to the second heater, and when the first heater and the second heater are energized, in the PWM control, the first heater is supplied within the unit time. The first energization period, which is the energization period, and the second energization period, which is the energization period for the second heater within the unit time, may be staggered.

According to this configuration, since the first energization period, which is the energization period of the first heater, and the second energization period, which is the energization period of the second heater, are staggered, the peak power can be suppressed. Further, since the first energization period and the second energization period are shifted within the unit time of the PWM control, fine control can be performed and each region can be efficiently heated.

Further, at least one of the seat cushion and the seat back is arranged on the left and right sides of the seat surface portion located in the center in the left-right direction and the left and right sides of the seat surface portion, and overhangs to the occupant side to support the occupant side portion. The first region may be the seating surface portion, and the second region may be the overhanging portion.

According to this, the seat surface portion and the overhanging portion can be efficiently heated.

Further, the vehicle seat includes a temperature sensor that detects the temperature of the seat surface portion, and the control device supplies a current only to the first heater when receiving an instruction to heat the vehicle seat. The surface portion heat treatment is executed, and after the seat surface portion heat treatment, the first energization period and the second energization period are set so that the sum of the first energization period and the second energization period becomes the unit time. The overhanging portion heat treatment is executed, and after the overhanging portion heat treatment, a feedback process for setting the first energization period and the second energization period is executed based on the detection temperature acquired from the temperature sensor, and the overhanging portion is executed. In the partial heat treatment, one of the first energization period and the second energization period may be set to a longer time than the other.

According to this, in the overhanging portion heat treatment, the first energization period and the second energization period are set so that the sum of the first energization period and the second energization period is the unit time, so that the unit time can be heated without waste. Can be used.

Further, the control device may set the second energization period to a longer time than the first energization period in the overhanging portion heat treatment.

According to this, in the overhanging portion heat treatment after the seating surface portion is preferentially heated by the seating surface portion heat treatment, the overhanging portion can be heated preferentially.

Further, the control device may set the first energization period to a longer time than the second energization period in the overhanging portion heat treatment.

According to this, in the overhanging portion heat treatment after the seat surface portion is preferentially heated by the seat surface portion heat treatment, for example, when the temperature of the seat surface portion is lower than a predetermined temperature, the seat surface portion is preferentially heated again. Can be done.

Further, in the seat surface heat treatment, the control device measures the time from receiving the instruction until the detected temperature reaches a predetermined temperature, and the time to execute the overhanging heat treatment based on the measured time. May be set.

According to this, the time for executing the overhanging portion heat treatment can be set to an appropriate time.

According to the present invention, it is only necessary to provide one thermostat for a plurality of heaters, so that the cost can be reduced.

Further, by sandwiching the connection portion between each heater and the thermostat with a sheet-shaped support, it is possible to prevent the connection portion between each heater and the thermostat from being short-circuited to the ground.

In addition, by connecting a thermistor to each heater, if an excessive current is likely to flow in each heater, the control device stops energization based on the signal detected by each thermistor without operating the thermostat. can do.

Further, by arranging the thermostat so as to overlap the center position of the contact portion between the seat cushion and the seat back in the front-rear direction, the thermostat arranged on the ground side can be sandwiched between the seat cushion and the seat back to protect the thermostat. ..

In addition, by arranging the thermostat so that the center position of the thermostat in the front-rear direction overlaps the contact part between the seat cushion and the seat back, the thermostat arranged on the ground side is sandwiched between the seat cushion and the seat back to protect it. Can be done.

Further, since the first energization period and the second energization period are shifted within the unit time of the PWM control, the peak power can be suppressed and each region can be efficiently heated.

Further, by using the first region as the seat surface portion and the second region as the overhanging portion, the seat surface portion and the overhanging portion can be efficiently heated.

Further, in the overhanging portion heat treatment, the first energization period and the second energization period are set so that the sum of the first energization period and the second energization period is the unit time, so that the unit time can be used for heating without waste. Can be used for.

Further, by setting the second energization period to a longer time than the first energization period in the overhanging portion heat treatment, the overhanging portion is heated in the overhanging portion heat treatment after the seat surface portion is preferentially heated by the seat surface portion heat treatment. It can be heated with priority.

Further, by setting the first energization period to a longer time than the second energization period in the overhanging portion heat treatment, for example, in the overhanging portion heat treatment after the seat surface portion is preferentially heated by the seat surface portion heat treatment, for example, the seat surface portion. When the temperature of is lower than the predetermined temperature, the seat surface portion can be heated with priority again.

In addition, by measuring the time from receiving the instruction until the detection temperature reaches a predetermined temperature and setting the time to execute the overhanging portion heat treatment based on the measured time, the time to execute the overhanging portion heat treatment can be set. It can be set at an appropriate time.

It is a perspective view of the vehicle seat which shows one Embodiment of the vehicle seat which concerns on this invention. It is a side view (a) which looked at the vehicle seat from the left-right direction, and is a plan view (b) which shows the structure of a planar heating element. It is a figure (a) which shows the relationship between a thermostat and a contact part, and the figure (b) which shows a modification of the relationship between a thermostat and a contact part. It is a circuit diagram which shows the relationship between the structure of a planar heating element and a control device and the like. It is a time chart (a)-(c) which shows the state of electric power in each process in a control device. It is a flowchart which shows the processing of a control device. It is a time chart which shows an example of the temperature change of the seat surface portion and the overhanging portion during the heat treatment in a control device.

Hereinafter, an embodiment of a vehicle seat according to the present invention will be described with reference to the accompanying drawings. The vehicle seat of one embodiment is configured as a vehicle seat S mounted on an automobile, for example, as shown in FIG. The vehicle seat S includes a seat cushion S1, a seat back S2, and a headrest S3 in which a pad material made of a cushion material such as urethane foam is covered with a skin material such as synthetic leather or cloth.

The seat cushion S1 is arranged in the center of the left and right sides of the seat surface portion S11 that contacts and supports the occupant's buttocks and thighs from below, and is arranged on the outside of both the left and right sides of the seat surface portion S11. It has an overhanging portion S12 overhanging on the occupant side to support it.
Similarly, the seat back S2 is also arranged in the center of the left and right sides of the seat surface portion S21 that contacts the occupant's back and supports the back from behind, and is arranged on the outside of both the left and right sides of the seat surface portion S21. It has an overhanging portion S22 overhanging to the occupant side to support the side portion.

Center heaters 11 and 12 are arranged as first heaters 10 on the inside of the skin of the seat surface portion S11 of the seat cushion S1 and the seat surface portion S21 of the seat back S2, respectively. Further, in the overhanging portion S12 of the seat cushion S1 and the overhanging portion S22 of the seat back S2, side heaters 21 and 22 are arranged as second heaters 20 inside the skin, respectively. That is, the portions heated by the first heater 10 are the seat surface portions S11 and S21, and the portions heated by the second heater 20 are the overhanging portions S12 and S22. That is, the seat surface portions S11 and S21 correspond to the first region, and the overhanging portions S12 and S22 correspond to the second region different from the first region.

The seat surface portion S11 of the seat cushion S1 has a built-in temperature sensor 30 that detects the temperature of the seat surface portion S11 in a portion corresponding to the first heater 10 inside the skin. The temperature sensor 30 is arranged at a position that is not affected by the body temperature of the occupant. For example, the temperature sensor 30 can be arranged at the lower part of the seat back S2 or at the rear part of the seat cushion S1. It should be noted that there is a substantially constant correlation between the temperature detected by the temperature sensor 30 and the temperature of the portion of the seat surface portion S11 that the occupant contacts. The control device 100 may perform control using the temperature itself detected by the temperature sensor 30 as the detection temperature, or estimates the temperature of the portion in contact with the occupant based on the above-mentioned correlation, and detects the estimated temperature. Control may be performed as the temperature T.

The control device 100 is arranged at an appropriate position on the vehicle seat S. The temperature sensor 30 described above is connected to the control device 100 so as to output a signal of the detection temperature T to the control device 100. Further, the first heater 10 and the second heater 20 are connected to the control device 100. Then, the control device 100 is supplied with electric power from the power supply device 90 driven by the battery mounted on the vehicle, and the electric power is supplied to the first heater 10 and the second heater 10 based on the detection temperature T acquired from the temperature sensor 30. It is configured to control the output of the heater 20. The power supply device 90 is configured to supply electric power within a predetermined upper limit output range for the first heater 10 and the second heater 20 of the vehicle seat S, and in the present embodiment, the first heater 10 is provided. The upper limit value P1 of the electric power with respect to the second heater 20 is made larger than the upper limit value P2 of the electric power with respect to the second heater 20. For example, the upper limit value P1 can be 80 W and the upper limit value P2 can be 60 W.

The upper limit of the electric power of each of the heaters 10 and 20 can be arbitrarily set, such as a magnitude relationship and a specific numerical value. For example, the upper limit of the electric power of each of the heaters 10 and 20 may be set to the same value, or the upper limit of the electric power of the first heater 10 may be smaller than the upper limit of the electric power of the second heater 20. ..

As shown in FIG. 2B, a planar heating element 50 provided with a center heater 11 and a side heater 21 is provided between the skin of the seat cushion S1 and the pad. Although such a planar heating element is also provided in the seat back S2, since it has substantially the same structure as the planar heating element 50 provided in the seat cushion S1, the planar heating element on the seat back S2 side is provided. The description of is omitted.

The planar heating element 50 includes a heater circuit 40 including heaters 11 and 21, and two sheet-shaped supports 51 sandwiching the heater circuit 40. The support 51 is made of an insulator such as a non-woven fabric, and sandwiches all the parts and wiring constituting the heater circuit 40. As a result, the connection portion CP between the heaters 11 and 21 and the thermostat 45, which will be described later, is sandwiched by the support 51.

The heater circuit 40 includes, in addition to the heaters 11 and 21, a connection terminal 41, a thermistor 43, and a thermostat 45.

The connection terminal 41 is a terminal to which electric power is supplied from the control device 100, and is connected to the control device 100 via the cable C1. The cable C1 is detachable from the connection terminal 41.

The connection terminal 41 is arranged at the central portion in the left-right direction at the rear end of the planar heating element 50.

The thermistor 43 is connected to the control device 100 and is arranged nearby so that the temperature of the center heater 11 can be detected. Desirably, it is more preferable that the sub-heater 13 (see FIG. 4) connected to the center heater 11 is arranged so as to detect the temperature.

The thermostat 45 has a function of spontaneously shutting off the energization of the heaters 11 and 21 by using a physical phenomenon without being controlled by the control device 100. The structure of the thermostat 45 will be described in detail later.

The thermistor 43 and the thermostat 45 are arranged at the same position in the front-rear direction at the rear end portion of the seat cushion S1. Specifically, as shown in FIG. 2A, the thermistor 43 and the thermostat 45 are arranged at the contact portion TP between the seat cushion S1 and the seat back S2. Here, the contact portion TP is a portion where the seat cushion S1 and the seat back S2 come into contact with each other. The seat cushion S1 and the seat back S2 each have a contact portion TP.

The positional relationship between the thermostat 45 and the contact portion TP in the front-rear direction will be described below. The description of the positional relationship between the thermistor 43, which has the same position in the front-rear direction as the thermostat 45, and the contact portion TP will be omitted.

As shown in FIG. 3A, the thermostat 45 is arranged so as to overlap the center position L1 in the front-rear direction of the contact portion TP. The position of the thermostat 45 is not limited to this, and the thermostat 45 may be arranged so that the center position L2 in the front-rear direction of the thermostat 45 overlaps the contact portion TP, for example, as shown in FIG. 3 (b). ..

Returning to FIG. 2B, the thermistor 43 is arranged on the right side of the connection terminal 41, and the thermostat 45 is arranged on the left side of the connection terminal 41. As a result, a space for installing the wiring of the heater circuit 40 is secured between the thermistor 43 and the thermostat 45. Note that FIG. 2B is a circuit diagram that simply shows the wiring of the heater circuit 40, and since the actual wiring is arranged so as to pass through a complicated path, the space as described above is effectively utilized. ..

Next, the configuration of the heater circuit 40 will be described in detail with reference to the circuit diagram of FIG. 4, which is a simplification of the circuit diagram of FIG. 2 (b).
The center heater 11 and the side heater 21 are connected to the control device 100 by individual wiring, and are configured to be independently controllable by the control device 100. The thermostat 45 is connected to the ground side with respect to the center heater 11 and the side heater 21.

The thermostat 45 includes an energization cutoff unit 45A that functions as a switch for switching the energization state, and a heat generation resistor 45B that heats the energization cutoff unit 45A. The energization cutoff unit 45A is made of a bimetal that deforms in response to a temperature change. Normally, the heaters 11 and 21 are connected to the ground, and when the temperature rises above a predetermined temperature, the heaters 11 and 21 and the ground are connected. It is configured to disconnect. The current flowing through the center heater 11 and the current flowing through the side heater 21 do not flow to the thermostat 45 at the same time but are supplied alternately by the control by the control device 100 described later. When such a current enters the thermostat 45, heat corresponding to the magnitude of the current is generated from the heat generation resistor 45B. When the temperature of the energization cutoff portion 45A becomes higher than a predetermined temperature due to this heat, the energization cutoff portion 45A is cut off, and the energization to each of the heaters 11 and 21 is cut off.

One end of the center heater 11 is connected to the control device 100, and the other end is connected to the sub heater 13. A thermistor 43 is arranged in the vicinity of the sub-heater 13. The thermistor 43 is connected to the control device 100.

The other end of the subheater 13 is connected to the thermostat 45. One end of the side heater 21 is connected to the control device 100, and the other end is connected to the thermostat 45.

The control device 100 has a function of individually stopping the energization of the center heater 11 and the side heater 21 based on the signal detected by the thermistor 43, specifically, the current that changes according to the temperature change of the subheater 13. ..

Specifically, the control device 100 stops energization of the center heater 11 when the temperature detected by the thermistor 43 is equal to or higher than a predetermined value, in other words, the current output from the thermistor 43 is equal to or higher than a predetermined threshold value. Then, when an excessive current is about to flow to the center heater 11, the control device 100 is configured to stop energization based on the current output from the thermistor 43 before the thermostat 45 is cut off. There is. Further, when an abnormality occurs in the thermistor 43 or the control device 100 and an excessive current is about to flow to the center heater 11, the thermostat 45 is cut off without depending on the control of the control device 100. It is possible to cut off the energization. Since the control of the side heater 21 using the thermistor 43 is the same as the control of the center heater 11, the description thereof will be omitted.

The control device 100 is connected to an operation switch of a heater mounted on the vehicle, and receives an instruction for heating the vehicle seat S from the operation switch to control energization of the first heater 10 and the second heater 20. As shown in FIGS. 5A to 5C, the control device 100 concentrates the first heater 10 in the heating period in which the detection temperature T is raised toward the target temperature T2 when instructed by the operation switch. The seat surface heat treatment that rapidly raises the temperature of the seat surface portions S11 and S21 that are in contact with the occupant and the heating of the second heater 20 are started, and the temperature of the overhanging portions S12 and S22 is changed to the seat surface portions S11 and S21. It is configured to execute a heat treatment of the overhanging portion to bring the temperature close to the above temperature and a feedback processing for adjusting the detected temperature T to match the target temperature T2 after the temperatures of the overhanging portions S12 and S22 have risen to some extent.
In a warm season or when the heater has been used once before the operation switch is operated, the detection temperature T may already be higher than the target temperature T2 when the operation switch receives a heating instruction. .. In that case, the control device 100 does not execute the control of the heating period referred to here, but starts the control from the feedback process.

The control device 100 controls the current supplied to the first heater 10 and the second heater 20 by setting the energization period per unit time Tu in each of the seat surface heat treatment, the overhanging portion heat treatment, and the feedback treatment. It is possible to execute PWM control. Then, when the control device 100 performs PWM control in the overhanging portion heat treatment and the feedback treatment to energize the first heater 10 and the second heater 20, the energization period to the first heater 10 within the unit time Tu The first energization period Ts1 is different from the second energization period Ts2, which is the energization period for the second heater 20 within the unit time Tu.

That is, the unit time when the first heater 10 is energized by the PWM control and the unit time when the second heater 20 is energized by the PWM control are the same unit time Tu. Then, within this unit time Tu, the start time and end time of the first energization period Ts1 and the start time and end time of the second energization period Ts2 are prevented so that the first energization period Ts1 and the second energization period Ts2 do not overlap. Are set respectively.

When the control device 100 receives an instruction to heat the vehicle seat S, the control device 100 executes the seat surface heat treatment shown in FIG. 5A. In the seat surface heat treatment, the first energization period Ts1 is set to the same time as the unit time Tu, and the second energization period Ts2 is set to 0. That is, in the seat surface heat treatment, the duty ratio of the current supplied to the first heater 10 (hereinafter, also referred to as “first duty ratio”) is set to 100%, and the duty of the current supplied to the second heater 20 is set. The ratio (hereinafter, also referred to as “second duty ratio”) is set to 0%. As a result, the control device 100 supplies a current only to the first heater 10 in the seat surface heat treatment. When the upper limit value P1 of the electric power for the first heater 10 is 80 W, the electric power of 80 W is supplied to the first heater 10.

Further, the control device 100 measures the time from receiving the instruction to the predetermined temperature T1 lower than the target temperature T2 in the seat surface heat treatment, and heats the overhanging portion based on this measurement time. The time to execute the process is set. Specifically, the control device 100 sets the time for executing the overhanging portion heat treatment to be longer as the measurement time is longer. When the temperature of the vehicle seat S at the start of heating the vehicle seat S is low, it takes a long time to heat the seat surface portions S11, S22 and the overhanging portions S12, S22. By prolonging the execution time of the overhanging portion heat treatment according to the long measurement time required for T to reach the predetermined temperature T1, the seat surface portions S11, S22 and the overhanging portions S12, S22 can be satisfactorily heated. can.

The control device 100 executes the overhanging portion heat treatment shown in FIG. 5B after the seat surface portion heat treatment. In the overhanging portion heat treatment, the first energization period Ts1 and the second energization period Ts2 are each set to a period larger than 0 so that the sum of the first energization period Ts1 and the second energization period Ts2 is the unit time Tu. ing. Further, in the present embodiment, the second energization period Ts2 is set to a longer time than the first energization period Ts1. As a result, in the overhanging portion heat treatment, the second duty ratio becomes larger than the first duty ratio, and the overhanging portion S12 can be preferentially heated.

As an example, in the overhanging portion heat treatment, the first duty ratio can be 40% and the second duty ratio can be 60%. In this case, when the upper limit value P1 of the electric power for the first heater 10 is 80 W and the upper limit value P2 of the electric power for the second heater 20 is 60 W, 32 W of electric power is supplied to the first heater 10 and the second heater 20 is supplied. A power of 36 W is supplied to 20.

The control device 100 executes the feedback process shown in FIG. 5C after the overhanging portion heat treatment. In the feedback process, the control device 100 sets the first energization period Ts1 and the second energization period Ts2 based on the detected temperature T acquired from the temperature sensor 30. Specifically, the control device 100 sets the first energization period Ts1 and the second energization period Ts2 so that the detection temperature T becomes the target temperature T2 in the feedback process. For example, the control device 100 executes PI control in the feedback process.

The control device 100 calculates the required control amount mv based on the detection temperature T and the target temperature T2. The required control amount mv is, for example, as a required control amount for so-called PI control.
mv = Kp × e + ie / Ki
Can be calculated by.

Here, e is the difference between the target temperature T2 and the detection temperature T, Kp is a proportional control constant, ie is an integral (integral) of e within a predetermined period in the past, and Ki is an integral control constant. Is. Each constant Kp, Ki is a required control amount mv as an output instruction value (value indicating the first energization period Ts1 and the second energization period Ts2) in the feedback processing after the detection temperature T approaches the target temperature T2. It is set to be available. Further, the detected temperature T and the target temperature T2 do not need to be a unit such as “° C.” in the calculation here, and may be a numerical value of the voltage output from the temperature sensor 30. The constants Kp and Ki may be appropriately adjusted according to the scale of these temperature values.

The processing of the control device 100 in the vehicle seat S as described above will be described with reference to FIG.
The control device 100 repeats the process from the start to the end shown in FIG. 6 for each control cycle. The control device 100 first determines whether or not a heater heating instruction has been received, and if there is no instruction (S41, No), the process is terminated, and if there is an instruction (S41, Yes), the process proceeds to step S42. , The seat surface heat treatment (S42 to S45) is executed.

In step S42, the control device 100 sets the first energization period Ts1 to the same time as the unit time Tu, so that the duty ratio of the current supplied to the first heater 10 is 100%, and the first heater 10 is set to 100. Output in%. After step S43, the control device 100 acquires the detected temperature T from the temperature sensor 30 (S43), and determines whether or not the detected temperature T is equal to or higher than the predetermined temperature T1 (S44).

If it is determined in step S44 that T ≧ T1, the control device 100 returns to the process of step S42. If it is determined in step S44 that T ≧ T1 (Yes), the control device 100 sets the execution time TM1 of the overhanging portion heat treatment based on the time from receiving the heating instruction until T ≧ T1. Set (S45).

After step S45, the control device 100 overhangs by setting the first energization period Ts1 and the second energization period Ts2 so that the sum of the first energization period Ts1 and the second energization period Ts2 is the unit time Tu. Part heat treatment is started (S46). Specifically, in step S46, for example, the control device 100 allocates 40% of the first half of the unit time Tu as the first energization period Ts1 and 60% of the latter half of the unit time Tu as the second energization period Ts2. Then, the heaters 10 and 20 are energized with a first duty ratio of 40% and a second duty ratio of 60%.

After step S46, the control device 100 determines whether or not the execution time TM1 has elapsed from the start of the overhanging portion heat treatment (S47). If it is determined in step S47 that the execution time TM1 has not elapsed (No), the control device 100 returns to the process of step S46. If it is determined in step S47 that the execution time TM1 has elapsed (Yes), the control device 100 sets the first energization period Ts1 and the second energization period Ts2, that is, each duty ratio, based on the detection temperature T. Then, the feedback process is executed so that the detected temperature T becomes the target temperature T2 (S48).

After step S48, the control device 100 determines whether or not the instruction to stop the heater has been received (S49). In step S49, if the control device 100 has not received the stop instruction (No), the process returns to the process of step S48, and if the stop instruction has been received (Yes), the heaters 10 and 20 are reached. (S50), the energization of the above is stopped, and the process is terminated.

Next, an example of the operation of the control device 100 will be described with reference to FIG. 7. In FIG. 7, the solid line indicates the temperature of the seat surface portions S11 and S21, and the broken line indicates the temperature of the overhanging portions S12 and S22.

As shown in FIG. 7, when the control device 100 receives an instruction for heating (time t1), the control device 100 executes the seat surface heat treatment. As a result, electric power is supplied only to the first heater 10, and the temperatures of the seat surface portions S11 and S21 rise. The overhanging portions S12 and S22 are heated with a gradient smaller than the temperature gradients of the seat surface portions S11 and S21 depending on the body temperature of the occupant seated on the vehicle seat S.

When the detection temperature T reaches a predetermined temperature (time t2), the control device 100 ends the seat surface heat treatment and starts the overhanging portion heat treatment. In the overhanging portion heat treatment, since the second energizing period Ts2 is set to a longer period than the first energizing period Ts1, the overhanging portions S12 and S22 are heated with priority over the seat surface portions S11 and S21. As a result, the temperature gradient of the overhanging portions S12 and S22 becomes larger than the temperature gradient of the seat surface portions S11 and S21, and the temperature of the overhanging portions S12 and S22 gradually approaches the temperature of the seat surface portions S11 and S21.

When the execution time TM1 elapses from the start of the overhanging portion heat treatment (time t3), the control device 100 ends the overhanging portion heating treatment and executes the feedback processing. Here, the execution time TM1 is determined based on the time from receiving the heating instruction until the detection temperature T reaches a predetermined temperature, that is, the execution time of the seat surface heat treatment. Therefore, at the end of the overhanging portion heat treatment, the execution time TM1 is determined. The temperature of the overhanging portions S12 and S22 and the temperature of the seat surface portions S11 and S21 are close to the target temperature T2. Therefore, by starting the feedback process in this state, the temperatures of the overhanging portions S12 and S22 and the temperatures of the seat surface portions S11 and S21 can be satisfactorily maintained at the target temperature T2.

Next, the operation of the control device 100 or the thermostat 45 when an excessive current is about to flow in the first heater 10 or the second heater 20 will be described with reference to FIG.

As shown in FIG. 4, when the current output from the thermistor 43 becomes equal to or higher than a predetermined threshold value while the first heater 10 or the second heater 20 is energized, the control device 100 causes the thermostat 45 to be before the thermostat 45 is cut off. Stop energizing. Further, when an excessive current is about to flow in the first heater 10 or the second heater 20 due to an abnormality of the control device 100 or the like during energization, the thermostat 45 is cut off and the energization is cut off.

As described above, according to the present embodiment, the following effects can be achieved.
Since it is only necessary to provide one thermostat 45 for the plurality of heaters 10 and 20, the cost can be reduced.

Since the connecting portion between the heaters 10 and 20 and the thermostat 45 is sandwiched between the sheet-shaped supports 51, it is possible to prevent the connecting portion between the heaters 10 and 20 and the thermostat 45 from being short-circuited to the ground.

In addition to the thermostat 45, a thermistor 43 for stopping energization is provided. Therefore, when an excessive current is about to flow in each of the heaters 10 and 20, the thermistor 43 detects it without operating the thermostat 45. The energization can be stopped by the control device 100 based on the signal.

Since the thermostat 45 is arranged so as to overlap the center position in the front-rear direction of the contact portion TP, the thermostat 45 arranged on the ground side can be protected by being sandwiched between the seat cushion S1 and the seat back S2.

Since the first energization period Ts1 which is the energization period of the first heater 10 and the second energization period Ts2 which is the energization period of the second heater 20 are shifted, the peak power can be suppressed. By suppressing the peak power in this way, the peak value of the current in the thermostat 45 to which the current flowing through each of the heaters 10 and 20 is supplied can be suppressed, so that even one thermostat 45 can function sufficiently. Can be done. Further, since the first energization period Ts1 and the second energization period Ts2 are shifted within the unit time Tu of PWM control, fine control can be performed and the seat surface portions S11 and S21 and the overhanging portions S12 and S22 are efficiently heated. be able to.

In the overhanging portion heat treatment, the first energization period Ts1 and the second energization period Ts2 are set so that the sum of the first energization period Ts1 and the second energization period Ts2 is the unit time Tu, so that the unit time Tu is heated without waste. Can be used for.

Since the second energization period Ts2 was set to a longer time than the first energization period Ts1 in the overhanging portion heat treatment, the overhanging portion was heated in the overhanging portion heat treatment after the seat surface portions S11 and S21 were preferentially heated by the seat surface portion heat treatment. Parts S12 and S22 can be heated with priority.

In the seat surface heat treatment, the execution time TM1 of the overhanging portion heat treatment is set based on the time from receiving the heating instruction until the detection temperature T reaches the predetermined temperature T1, so that the time for executing the overhanging portion heat treatment is set. , Can be set at an appropriate time.

Although the embodiment of the present invention has been described above, the present invention can be appropriately modified and carried out as shown in the following other embodiments.

In the above embodiment, the first region is the seat surface portions S11 and S21, and the second region is the overhanging portions S12 and S22, but the present invention is not limited thereto. The first region may be any portion of the seat cushion and the seat back, and the second region may be any portion of the seat cushion and the seat back as long as it is different from the first region. There may be. For example, a part of the seat cushion may be a first area and a part of the seat back may be a second area.

In the above embodiment, the second energization period Ts2 is set to a longer time than the first energization period Ts1 in the overhanging portion heat treatment, but the present invention is not limited to this, and the first energization period in the overhanging portion heat treatment is not limited to this. May be set to a time longer than the second energization period.

Here, for example, when the end condition of the seat surface heat treatment is that a predetermined time has elapsed after receiving the heating instruction, the seat surface may not be very warm at the end of the seat surface heat treatment. In such a case, in the overhanging portion heat treatment, it is necessary to heat the seat surface portion more preferentially than the overhanging portion. In such a case, by setting the first energization period to a longer time than the second energization period in the overhanging portion heat treatment, the seat surface portion can be heated with priority again.

In the overhanging portion heat treatment, the first energization period and the second energization period may be set to the same time.

In the above embodiment, each energization period Ts1 and Ts2 are set to fixed values in the overhanging portion heat treatment, but the present invention is not limited to this. Each energization period Ts1 and Ts2 may be changed so that the ratio of Ts2 becomes large.

The positions of the thermistor 43 and the thermostat 45 are not limited to the above-described embodiment, and can be arranged at any position. Further, in the above-described embodiment, the number of thermistors 43 is one, but a plurality of thermistors 43 may be provided for each heater.

In the above embodiment, the vehicle seat S used in an automobile is exemplified as the vehicle seat, but the present invention is not limited to this, and other vehicle seats, for example, a seat used in a ship, an aircraft, or the like. It can also be applied to. Further, in the above-described embodiment, an independent type seat such as that used for the driver's seat of a passenger car is exemplified, but the present invention may be adopted for a bench type seat that is often used for the rear seat of a passenger car. can.

In the above embodiment, the temperature sensor 30 is provided on the seat surface portion S11 of the seat cushion S1, but the present invention is not limited to this. For example, a temperature sensor may be provided on the seat surface portion of the seat back, or the seat cushion. A temperature sensor may be provided on each seat surface of the seat back.

Further, each element described in the above-described embodiment and modification may be arbitrarily combined and carried out.

10 1st heater 20 2nd heater 45 Thermostat S Vehicle seat S1 Seat cushion S2 Seat back S11 Seat surface S12 Overhanging part S21 Seating surface S22 Overhanging part

Claims (10)

A seat cushion and a seat back are provided , and at least one of the seat cushion and the seat back is arranged on the left and right sides of the seat surface portion located in the center in the left-right direction and to support the side portion of the occupant. It is a vehicle seat having an overhanging portion on the occupant side .
A first heater that heats the seat surface of the seat cushion and the seat back, and
A second heater that heats the overhanging portion of the seat cushion and the seat back, and
A thermostat that shuts off the power and
A temperature sensor that detects the temperature of the seat surface and
A control device for controlling energization of the first heater and the second heater is provided.
The first heater and the second heater are configured to be independently controllable.
The thermostat is connected to the ground side with respect to the first heater and the second heater.
The control device is
By setting the energization period per unit time, it is possible to execute PWM control for controlling the current supplied to the first heater and the second heater.
When energizing the first heater and the second heater,
In the PWM control,
The first energization period, which is the energization period for the first heater within the unit time, and the second energization period, which is the energization period for the second heater within the unit time, are staggered.
When instructed to heat the vehicle seat, the seat surface heat treatment that supplies an electric current only to the first heater is executed.
After the seat surface heat treatment, the overhanging portion heat treatment for setting the first energization period and the second energization period is executed so that the sum of the first energization period and the second energization period becomes the unit time. ,
After the overhanging portion heat treatment, a feedback process for setting the first energization period and the second energization period is executed based on the detected temperature acquired from the temperature sensor.
In the seat surface heat treatment, the time from receiving the instruction until the detection temperature reaches a predetermined temperature is measured, and the time for executing the overhanging portion heat treatment is set based on the measured time. Vehicle seat. The vehicle seat according to claim 1, wherein the first heater and the connection portion between the second heater and the thermostat are sandwiched between sheet-shaped supports. The vehicle seat according to claim 1 or 2, wherein the thermistor for detecting the temperature of the first heater is provided. The control device is
The vehicle seat according to claim 3, wherein the energization of the first heater or the second heater is stopped based on the signal detected by the thermistor. The seat cushion and the seat back have contact portions that come into contact with each other.
The vehicle seat according to any one of claims 1 to 4, wherein the thermostat is arranged so as to overlap the center position in the front-rear direction of the contact portion. The seat cushion and the seat back have contact portions that come into contact with each other.
The vehicle seat according to any one of claims 1 to 5, wherein the thermostat is arranged so that the center position of the thermostat in the front-rear direction overlaps with the contact portion. The control device is
The one according to any one of claims 1 to 6 , wherein in the overhanging portion heat treatment, one of the first energization period and the second energization period is set to a longer time than the other. Vehicle seat. The vehicle seat according to claim 7 , wherein the control device sets the second energization period to a longer time than the first energization period in the overhanging portion heat treatment. The vehicle seat according to claim 7 , wherein the control device sets the first energization period to a longer time than the second energization period in the overhanging portion heat treatment. With more headrests
The vehicle seat according to any one of claims 1 to 9, wherein the seat cushion, the seat back, and the headrest have a pad material and a skin material that covers the pad material.

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