JP2013169909A - Headrest device for vehicle seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of problems, which are contradictory to each other, due to the setting of feedback control responsiveness by switching the control methods while discriminating between when the responsiveness is requested and when the stability is requested.SOLUTION: A headrest device for a vehicle seat includes: a measuring means that measures a distance between the head of an occupant sitting on a vehicle seat and a headrest; a normal mode in which the position of the headrest is adjusted so that the measurement distance by the measuring means becomes a target distance, and the adjustment is executed with a predetermined response delay with respect to a change in measurement distance when executing the adjustment; and a forward adjustment mode and a backward adjustment mode respectively in which the position of the headrest is adjusted at response speed faster than that of the normal mode when the distance measured by the measuring means is larger than a predetermined level.

Description

  The present invention relates to a headrest device for a vehicle seat that automatically adjusts the position of the headrest relative to the head of an occupant seated on the vehicle seat.

  An apparatus has been developed that measures the distance between the head and the headrest of an occupant seated on a seat and performs feedback control so that the distance becomes a target value (see Patent Document 1 below).

JP 2010-143572 A

However, in the technique of the above-mentioned patent document 1, contradictory problems arise due to the setting of feedback control response. That is, when trying to improve the responsiveness by the feedback control, the headrest moves frequently, which causes trouble for the occupant. On the other hand, if the headrest is not moved frequently, the passenger feels that the responsiveness is poor.
In view of such a problem, an object of the present invention is to distinguish between when responsiveness is required and when stability is required, and by switching the control method, each other by setting the responsiveness of feedback control The goal is to avoid conflicting problems.

The first invention of the present invention is a measuring means for measuring the distance between the head of the occupant seated on the vehicle seat and the headrest, and adjusting the position of the headrest so that the measurement distance by the measuring means becomes a target distance, In the adjustment, the first adjusting means for adjusting with a predetermined response delay with respect to the change of the measuring distance, and when the distance measured by the measuring means is larger than the predetermined level, the response speed is faster than the first adjusting means. A vehicle seat headrest device comprising: a second adjustment unit that adjusts a position of the headrest.
According to the first aspect of the invention, the position adjustment of the headrest is normally performed with a response delay by the first adjustment means, and when the measurement distance becomes large, the second adjustment means has a faster response speed than the first adjustment means. The position of the headrest is adjusted. Therefore, the headrest position can be stably adjusted when the measurement distance does not change greatly, and the headrest position can be adjusted with good response when the measurement distance changes greatly.

According to a second aspect of the present invention, in the first aspect, the second adjusting means starts adjusting the position of the headrest when the distance is greater than a predetermined level and the direction of change in the distance does not change for a predetermined period. This is a headrest device for a vehicle seat.
According to the second invention, when the measurement distance is increased and the position adjustment of the headrest is performed based on the second adjustment means, the position adjustment is started after confirming that the change in the distance is stable. Therefore, when the change of the distance is temporary, it is possible to prevent a problem that the position adjustment is performed following the change.

According to a third aspect of the present invention, in the second aspect, the determination of the direction of the change in the distance in the second adjustment means is performed such that the distance measured this time with respect to the distance measured last time is within a predetermined range on both large and small sides. It is a headrest device for a vehicle seat, which is performed depending on which side is changed beyond.
According to the third aspect of the invention, the determination of the direction of the change in distance is performed depending on which side the change width exceeds the predetermined range and changes to which side. Therefore, even if the accuracy of distance measurement is low, the direction of the distance change can be confirmed with a small measurement period.

It is a disassembled perspective view which shows the external appearance of one Embodiment of this invention. It is a system block diagram in the said embodiment. It is explanatory drawing explaining the positional relationship of the up-down direction of a headrest with respect to the passenger | crew head in the said embodiment. It is explanatory drawing explaining the positional relationship of the front-back direction of a headrest with respect to the passenger | crew head in the said embodiment. It is explanatory drawing explaining the control outline of the computer in the said embodiment. It is a flowchart explaining the processing content of the mode determination process of FIG. It is a flowchart explaining the processing content of the 1st part in the head movement determination process of FIG. It is a flowchart explaining the processing content of the 2nd part in the head movement determination process of FIG. It is a flowchart explaining the process content of the 3rd part in the head movement determination process of FIG. It is a time chart explaining the processing content of head movement direction determination in FIG.

  Each embodiment shown in each drawing is an example in which the present invention is applied to one independent vehicle seat 60. As shown in FIG. 1, a known capacitance sensor 50 is provided on the front surface of the headrest 63 at a portion facing the occupant's head (not shown), and the headrest 63 is moved in the front-rear direction in the headrest 63. A front / rear adjustment motor 30 for controlling the front / rear adjustment is provided, and a headrest control circuit 20 for driving and controlling the front / rear adjustment motor 30 is also included. Further, the seat back 62 incorporates a vertical adjustment motor 40 for moving the headrest 63 in the vertical direction, and a main control circuit 10 for driving and controlling the vertical adjustment motor 40 is also incorporated. . Although not shown, the capacitance sensor 50 is composed of five sensors divided into five zones in the vertical direction. In FIG. 1, reference numeral 61 denotes a seat cushion.

As shown in FIG. 2, the main control circuit 10 includes a computer 11, a vertical drive circuit 12, and a manual switch 13. The computer 11 receives an operation signal from the vertical adjustment motor 40 and outputs a signal for driving the vertical adjustment motor 40 via the vertical drive circuit 12. The manual switch 13 is provided around the seat 60, and a switch signal is input to the computer 11 so that the headrest 63 can be driven back and forth and up and down by any operation of the occupant.
The headrest control circuit 20 includes a computer 21, a front / rear drive circuit 22, and a capacitance detection IC 23. The computer 21 receives an operation signal from the front / rear adjustment motor 30 and outputs a signal for driving the front / rear adjustment motor 30 via the front / rear drive circuit 22. The electrostatic capacitance detection IC 23 receives the electrostatic capacitance signal from the electrostatic capacitance sensor 50 that is an antenna, converts it into a voltage signal proportional to the distance from the occupant's head, and supplies it to the computer 21. The computer 21 converts the voltage signal from the capacitance detection IC 23 into a distance signal to the head. As described above, the electrostatic capacity sensor 50 measures the electrostatic capacity divided into five zones in the vertical direction of the headrest 63. Therefore, the computer 21 via the electrostatic capacity detection IC 23 detects the electrostatic capacity of each zone. The height of the occupant's head P can be detected from the size of the occupant. This is because, as shown in FIG. 3, the capacitance of the capacitance sensor 50 corresponding to the rear apex of the head P is smaller than the other zones because the distance from the head P is smaller, thereby increasing the capacitance. The position of the part P can be detected.
The computer 11 and the computer 21 send and receive signals to each other so that they can cooperate with each other. The computer 11 is connected so as to receive various signals representing the state of the vehicle, such as a vehicle power switch, a seating detection switch for a passenger on the vehicle seat 60, and a seat belt detection detection switch for passenger protection. In FIG. 2, various vehicle signals are represented as vehicle signals 70.

As shown in FIGS. 3 and 4, the headrest 63 includes a base portion 65 and a moving portion 66 fixed so as to be movable in the front-rear direction with respect to the base portion 65. At the same time, it is fixed so as to be movable in the vertical direction. Therefore, the front / rear adjustment motor 30 is provided in the base 65 so as to move the moving part 66 in the front / rear direction, and the vertical adjustment motor 40 is provided in the seat back 62 so as to move the stay 64 in the vertical direction. It has been. The above-described capacitance sensor 50 is provided on the head P side surface of the moving unit 66.
As shown in FIG. 3, the amount of vertical displacement between the rear tip of the passenger's head P and the center of the moving part 66 of the headrest 63 is set to “h” and will be used in the following description. Further, as shown in FIG. 4, the distance in the front-rear direction between the rear tip of the passenger's head P and the front surface of the moving portion 66 of the headrest 63 is “x”, and the reference position O of the moving portion 66 of the headrest 63 is In the following description, the amount of movement in the front-rear direction is “y”. The reference position O is the position of the surface of the moving part 66 on the head P side when the moving part 66 is in the neutral position (position indicated by a broken line in FIG. 4).

The position adjustment control of the headrest 63 will be described based on FIG.
<Initial adjustment mode>
A vehicle power switch (not shown) is turned on, an occupant sits on the vehicle seat 60, a seating sensor (not shown) detects the seating, and the occupant wears a seat belt and a detection switch (not shown) When the wearing is detected, the vehicle signal 70 transmits a signal to the computer 11. In the computer 11, when a certain time (for example, 10 seconds) elapses thereafter, processing in the initial adjustment mode is executed.
In this initial adjustment mode, based on the signal from the capacitance sensor 50, the height (the amount of vertical displacement) h and the distance x in the front-rear direction with respect to the headrest 63 are measured, and the measurement results thereof. Based on the above, it is determined whether or not the measured distance x in the front-rear direction between the occupant's head P and the headrest 63 is smaller than an upper limit value (for example, 100 mm). Until the distance in the front-rear direction is determined to be smaller than the upper limit value, the front-rear adjustment motor 30 is operated to move the headrest 63 in the front-rear direction. Thereafter, when it is determined that the distance x in the front-rear direction is smaller than the upper limit value, the height of the headrest 63 is adjusted so that the vertical adjustment motor 40 is operated and the vertical displacement h becomes a predetermined value (for example, 10 mm). Is preliminarily adjusted. Thereafter, the position of the headrest 63 is adjusted based on a signal from the capacitance sensor 50 so that the distance x in the front-rear direction becomes a target distance (for example, 30 mm). When the front / rear position of the headrest 63 is adjusted in this way, the height of the headrest 63 is adjusted so that the vertical displacement h is finally a predetermined value (for example, 10 mm).
When the above initial adjustment mode processing is completed, mode determination processing is executed. As shown in FIG. 6, after the initial adjustment mode described above is processed in step S1, mode determination is started in step S2, and the position of the occupant's head P is detected in step S3. That is, information on the distance x in the front-rear direction and the amount of shift h in the vertical direction is taken into the computer 21. When the head position detection is completed, a head motion determination process is executed in step S4.

<Normal mode 1>
In detail, the head movement determination process in step S4 is performed as shown in FIGS. FIGS. 7 to 9 show a single control flow, but are divided into three because of the restriction of the size of the drawing.
In step S41 shown in FIG. 7, the determination process is started, and xa <c (for example, a is 30 mm, c is -20 mm) and y ≦ 0 is satisfied, or b <xa ≦ When z−a (for example, b is 20 mm, z is 100 mm) and d ≦ y (for example, d is 30 mm) is satisfied, the head movement direction determination result log (described later, head movement) (Recording that the direction determination has been made) is deleted. When the process of step S45 is executed, the counter for the number of times the head movement direction determination is continued is reset, and the normal mode process is executed in step S46. When the parameters a, c, z, etc. are as shown in the above example, the distance x is smaller than 10 mm and the headrest 63 is in a position retracted from the reference position O, or the distance x is 50 to 100 mm. Is in a position advanced by 30 mm or more from the reference position O, the normal mode is executed.
When the normal mode is executed, while the deviation of the distance x between the headrest 63 and the occupant head P with respect to the target distance is within a specified range (for example, x = 0 to 100 mm), the average value is continuously obtained. When a threshold value (for example, 25 mm <x <35 mm) is exceeded, the headrest 63 is moved in the front-rear direction so that the average value becomes zero. Thus, since the movement of the headrest 63 is not performed unless the average value exceeds the threshold value, it is possible to prevent the headrest from operating frequently and causing the occupant to feel annoyance. After this normal mode is executed, the mode determination process returns again as shown in FIG. Here, the process of averaging the difference of the distance x with respect to the target distance corresponds to having a predetermined response delay in the first adjusting means of the present invention.

<Vertical adjustment mode>
Further, the determination process is started in step S41, and when c ≦ xa ≦ b (corresponding to a predetermined level in the present invention) is established, the head movement direction determination result log is deleted in step S42. When the process of step S42 is executed and the head movement direction determination continuation count is reset, the head height detection start determination process is executed in step S43. At this time, after completion of the initial adjustment, T ₁ second (for example, If 10 seconds) has not elapsed or T ₁ second has elapsed after resetting the up / down adjustment timer, the process proceeds to step S44, and processing in the up / down adjustment mode is executed. Assuming that the parameters a, b, c, etc. are as shown in the above example, the distance x is 10 to 50 mm and 10 seconds have not elapsed since the completion of the initial adjustment, or 10 seconds have elapsed since the completion of the previous vertical adjustment. If so, the process in the vertical adjustment mode in step S44 is executed.
When the processing in the vertical adjustment mode is executed, an average value of the head height for a certain period is obtained from the signal from the capacitance sensor 50, and the vertical displacement amount h of the headrest 63 is calculated from the head height. The height of the headrest 63 is adjusted so that the deviation amount h is a predetermined value (for example, 10 mm). This adjustment is performed only when the threshold is exceeded. After the adjustment is completed, the up / down adjustment timer is reset. After the up / down adjustment mode is executed, the mode determination process is resumed as shown in FIG.

<Normal mode 2>
In step S43, a head height detection start determination process is executed. At this time, after completion of the initial adjustment, if T ₁ second has elapsed, or if T ₁ second has not elapsed after resetting the vertical adjustment timer, step S46 is performed. Then, the normal mode processing is executed. Assuming that the parameters a, b, c, etc. are as illustrated above, the distance x is 10 to 50 mm, and 10 seconds have elapsed after completion of the initial adjustment, or 10 seconds have elapsed since the completion of the previous vertical adjustment. If not, normal mode processing is executed.
Assuming that the vertical adjustment has been performed in the initial adjustment, even if within 10 seconds after the completion of the initial adjustment, 10 seconds have not passed since the completion of the vertical adjustment, so the condition that the distance x is 10 to 50 mm is satisfied. If the distance x is 10 to 50 mm, the normal mode process is executed even after 10 seconds have elapsed from the completion of the initial adjustment. On the other hand, the processing in the up / down adjustment mode is executed immediately if the condition that the distance x is 10 to 50 mm is satisfied within 10 seconds after the completion of the initial adjustment, but is executed every 10 seconds thereafter. Since the normal mode processing is performed by the computer 21 and the vertical adjustment mode processing is performed by the computer 11, the processing of each mode is performed in parallel by the computers 11 and 21 simultaneously.

<Front adjustment mode and rear adjustment mode>
In step S41, the determination process is started, and when b <xa <za is satisfied and y <d is satisfied, a forward motion prediction process is executed in step S49. Further, when x-a <c is satisfied and 0 <y is satisfied, the backward motion prediction process is executed in step S50. Assuming that the parameters a, b, c, etc. are as shown in the above example, when the distance x is 50 to 100 mm and the headrest 63 is in the retracted position from the position advanced by 30 mm from the reference position O, the forward operation is expected, that is, the front It is stored that the operation process has been started. Further, when the distance x is less than 10 mm and the headrest 63 is in the forward position from the reference position O, it is stored that the backward motion expectation, that is, the backward motion processing has been started.

<Unmeasurable mode>
When the determination process is started in step S41 and za <xa is established, the head movement direction determination result log is deleted in step S47. When the process of step S47 is executed and the head movement direction determination continuation count is reset, the process of the measurement impossible mode is executed in step S48. Assuming that the parameters a and z are as illustrated above, the measurement impossibility mode is executed when the distance x is greater than 100 mm. In the measurement impossible mode, the operation of the front / rear adjustment motor 30 is stopped. After this non-measurable mode is executed, the process returns to the mode determination process again as shown in FIG.

<Distribution to each mode>
The conditions distributed from the start of the determination process in step S41 to the normal mode 1, vertical adjustment mode, normal mode 2, forward adjustment mode, backward adjustment mode, and measurement impossible mode described above are summarized as follows. .
First, when the distance x between the occupant's head P and the headrest 63 is relatively small, for example, 10 to 50 mm (corresponding to a predetermined level in the present invention), the mode shifts to the vertical adjustment mode and the normal mode 2. When the distance x is a little larger, for example, 50 to 100 mm, the mode shifts to the normal mode 1 or the forward adjustment mode, and due to the magnitude of the forward movement amount y from the reference position O of the moving part 66 of the headrest 63 at that time, Which mode to move to is determined. If the amount of movement y is smaller than 30 mm, for example, the forward adjustment mode is entered, and if it is larger than 30 mm, the mode 1 is shifted to the normal mode 1. When the distance x is small, for example, smaller than 10 mm, the mode is shifted to the normal mode 1 or the rear adjustment mode, and the mode to be shifted is determined depending on the amount of movement y at that time. If the amount of movement y is greater than 0 mm, for example, the rear adjustment mode is selected. When the distance x is significantly large, for example, greater than 100 mm, the mode is shifted to the measurement impossible mode.
By performing such processing, after the adjustment in the initial adjustment mode, the headrest 63 is adjusted in the front-rear and vertical directions when the occupant moves the head P. When the distance x has become significantly large, it waits for the distance x to return to a measurable level in the non-measurable mode, and after returning to the measurable level, the normal mode, forward adjustment mode, or backward adjustment Depending on the mode, the distance x is controlled to be a relatively small level, and after the distance x reaches a relatively small level, the normal mode or the vertical adjustment mode is used so that the distance x becomes the target distance or in the vertical direction. The shift amount h is controlled to be a predetermined amount.

<Forward adjustment mode>
As shown in FIG. 8, when the forward motion prediction is executed in step S49 and the forward motion prediction determination is not continued at this time, that is, when the process of step S49 is the first time, the head motion direction determination result in step S51. Log deletion is performed, and the number of times the head movement direction determination is continued is reset. On the other hand, when the forward motion prediction is executed in step S49, if the forward motion prediction determination is continued, that is, if the processing in step S49 was performed last time, the processing in step S51 is skipped, and the head in step S52. A part movement direction determination process is executed (the head movement direction determination in step S52 will be described later with reference to FIG. 10). At this time, it is determined that the occupant's body is tilted forward compared to the previous time, that is, the head has been moved forward, or has been stopped from the previous time, and the number of determinations is n When it is continued _three times (for example, three times), it is determined that the direction of the change in the distance x does not change for a predetermined period, the head forward motion is determined in step S53, and the head motion direction determination result log in step S54 Erasing is performed, and the head movement direction determination continuation count is reset. In step S55, the forward adjustment mode process is executed. Here, the above n ₃ times corresponds to a predetermined period in the second adjusting means of the present invention.
In step S55, the front / rear adjustment motor 30 is operated so that the position of the headrest 63 becomes the target distance based on the distance x measured n ₃ times. At this time, since the position adjustment of the headrest 63 is immediately performed based on the distance x measured at the n _3rd time, the position adjustment is performed at a higher response speed than in the normal mode described above. After the forward adjustment mode is executed, the mode determination process returns again as shown in FIG.
In step S52, it is determined that the occupant's body is tilted forward compared to the previous time, that is, the head has been moved forward, or has been stopped from the previous time. If n is not continued _three times, the head movement direction determination result log is accumulated in step S58, and it is recorded that the head movement direction determination in the forward direction is being performed. Is incremented. Thereafter, normal mode processing is executed in step S46 described above.
If it is determined in step S52 that the occupant's body is tilted backward compared to the previous time, that is, the head is moved backward, the head motion is not performed in step S56, and the head motion direction is determined in step S57. The determination result log is erased, and the head movement direction determination continuation count is reset. Thereafter, normal mode processing is executed in step S46 described above.
FIG. 10 illustrates the head movement direction determination processing in steps S52 to S54 and steps S56 to S58 in FIG. In FIG. 10, the head position measured for the second time is tilted forward beyond a predetermined range T with respect to the head position measured for the first time (x + y in FIG. 4). Accordingly, the process proceeds from step S52 to step S58, and the head movement direction determination result log is accumulated. In the next measurement for the third time, the head position is determined to be in a stopped state because the vehicle is not tilted forward or backward beyond the predetermined range T, and the process proceeds from step S52 to step S58 again, and the head movement direction determination result log Accumulation is performed. In this way, compared to the previous time, the current measurement result is determined that the head is tilted forward beyond the predetermined range T, or that the head is tilted forward or backward beyond the predetermined range T and is in a stopped state. If this state continues for n ₃ times, the forward adjustment mode of step S55 is executed by the processing from step S52 to step S53.

<Rear adjustment mode>
As shown in FIG. 9, when the backward motion prediction is executed in step S50 and the backward motion prediction determination is not continued at this time, that is, when the process of step S50 is the first time, the head motion direction determination result in step S51. Log deletion is performed, and the number of times the head movement direction determination is continued is reset. On the other hand, when the backward motion prediction is executed in step S50, if the backward motion prediction determination is continued, that is, if the processing in step S50 was performed last time, the processing in step S51 is skipped, and the head in step S60. The head movement direction determination process is executed (whether the head movement direction determination in step S60 is moving beyond the predetermined range T as well as the head movement direction determination in step S52 described above). Is determined by whether or not). At this time, it is determined that the occupant's body is tilted backward compared to the previous time, that is, the head is moved backward beyond the predetermined range T, or does not move beyond the predetermined range T from the previous time, When it is determined that the vehicle is stopped, and the number of determinations continues for n ₄ times (for example, 3 times), it is determined that the direction of change in the distance x does not change for a predetermined period, and the head is determined in step S61. In step S62, the head movement direction determination result log is erased, and the head movement direction determination continuation count is reset. In step S63, the rear adjustment mode process is executed. Here, the above n ₄ times corresponds to a predetermined period in the second adjusting means of the present invention.
In step S63, operating the front and rear motor 30 so that the position of the headrest 63 becomes a target distance based on the distance x measured in ₄ th n. At this time, since the position adjustment of the headrest 63 is immediately performed based on the distance x measured n ₄ times, the position adjustment is performed at a faster response speed than in the normal mode described above. After the backward adjustment mode is executed, the mode determination process returns again as shown in FIG.
In step S60, it is determined that the occupant's body is tilted backward compared to the previous time, that is, the head has been moved backward, or has been stopped from the previous time. When n ₄ times are not continued, the process proceeds from step S60 to step S58, the head movement direction determination result log accumulation is performed, and it is recorded that the head movement direction determination in the backward direction is being performed. The counter for the number of determination continuations is incremented. Thereafter, normal mode processing is executed in step S46 described above.
If it is determined in step S60 that the occupant's body is tilted forward compared to the previous time, that is, the head is moved forward, in step S56 there is no head movement, and in step S57 the head movement direction. The determination result log is erased, and the head movement direction determination continuation count is reset. Thereafter, normal mode processing is executed in step S46 described above.
The description of the forward adjustment mode accompanying the forward tilting operation of the head described above based on FIG. 10 is the same as the backward adjustment mode accompanying the backward tilting operation of the head only by changing the forward tilt to the backward tilt. .

According to the above embodiment, the position adjustment of the headrest 63 is performed with a response delay by performing the averaging process of the deviation of the distance x between the passenger's head and the headrest 63 with respect to the target distance in the normal mode. Is called. On the other hand, when the measurement distance increases, the position of the headrest 63 is adjusted at a faster response speed than in the normal mode in the forward adjustment mode or the backward adjustment mode. Therefore, the position adjustment of the headrest 63 can be stably performed when the measurement distance does not change greatly, and the position of the headrest 63 can be adjusted with good response when the measurement distance changes greatly.
Further, when the position x of the headrest 63 is adjusted based on the front adjustment mode or the rear adjustment mode when the measurement distance x is increased, the movement of the head P measured during a predetermined period (n ₃ times or n ₄ times). Position adjustment is started after confirming that the direction is stable in one direction including the stop state. Therefore, when the change of the distance x is temporary, it is possible to prevent a problem that the position adjustment is performed following the change.
Further, the direction of the change in the distance x in the front adjustment mode and the rear adjustment mode is determined based on whether or not the change width exceeds the predetermined range T. Therefore, even if the accuracy of distance measurement is low, the direction of the distance change can be confirmed with a small measurement period.

  In the above embodiment, the process of the capacitance sensor 50, the capacitance detection IC 23, and step S3 corresponds to the measurement unit of the present invention, and the process of step S46 corresponds to the first adjustment unit of the present invention. The processing of S41, step S49, step S51 to step S58, step S50, and step S60 to step S63 corresponds to the second adjusting means of the present invention.

The present invention is not limited to the appearance and configuration described in the above embodiment, and various modifications, additions, and deletions can be made without changing the gist of the present invention. For example,
1. The response delay in the first adjusting means may be performed by making the amount of adjusting the position of the headrest smaller than the measurement distance.
2. In the adjustment of the headrest by the second adjustment means, the response speed may be made faster than the adjustment by the first adjustment means by increasing the adjustment amount per time as compared with the case of the first adjustment means.

DESCRIPTION OF SYMBOLS 10 Main control circuit 20 Headrest control circuit 30 Front-rear adjustment motor 40 Vertical adjustment motor 50 Capacitance sensor 60 Vehicle seat 63 Headrest

Claims (3)

Measuring means for measuring the distance between the head of the passenger seated on the vehicle seat and the headrest;
First adjustment means for adjusting the position of the headrest so that a measurement distance by the measurement means becomes a target distance, and adjusting with a predetermined response delay with respect to a change in the measurement distance;
A vehicle seat headrest device comprising: a second adjustment unit that adjusts the position of the headrest at a faster response speed than the first adjustment unit when the distance measured by the measurement unit is greater than a predetermined level. In claim 1,
The vehicle seat headrest device, wherein the second adjustment means starts position adjustment of the headrest when the distance is greater than a predetermined level and the direction of change in the distance does not change for a predetermined period. In either claim 1 or 2,
The determination of the direction of the change of the distance in the second adjusting means is performed based on whether the distance measured this time with respect to the previously measured distance has changed over a predetermined range on both sides of the large and small sides. A vehicle seat headrest device.

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