JP2010235021A - Pneumatic pressure control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control the pneumatic pressure in an airbag for a seat with excellent accuracy. <P>SOLUTION: A pneumatic pressure control device includes a pressure sensor for detecting the pneumatic pressure in an airbag provided inside a seat, a firs control circuit for performing the control to repeat the intermittent operation that a pump for feeding air to the airbag is operated for the second time after the pump is stopped for the first time, and a second control circuit which detects the pneumatic pressure in the airbag by the pressure sensor at the first time when the pump is stopped, and performs the control to repeat the intermittent operation of the pump until the pneumatic pressure in the airbag reaches the target value according to the differential pressure between the detected pressure and the target pressure of the airbag. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a pneumatic control device.

For example, some seats for vehicles and the like adjust hardness by controlling the air pressure of a built-in air bag. As a specific example, an air pressure control device disclosed in Patent Document 1 includes a valve, a pump, and the like for sucking or exhausting air bags corresponding to each part of a seat, and a pressure sensor that detects air pressure of the air bags. It controls based on a detection result (namely, detection pressure of an air bag).
For example, when regenerating the shape of the seat, the air pressure control device compares the detected pressure of the air bag with the target pressure while supplying air to the air bag by the pump, and determines that the detected pressure has reached the target pressure. At that time, the air supply operation is stopped.

Japanese Patent Publication No. 6-95969

By the way, the detected pressure of the air bag when the pump is operating and supplying air to the air bag is compared with the detected pressure of the air bag when the pump is stopped after the supply operation is finished. For example, when there is an error due to instability of the air pressure, etc., when the air pressure control is performed based on the detected pressure during the operation of the pump, the final air pressure of the air bag is allowed with respect to the target pressure. There is a possibility that they do not match within the error range.
Thus, when the accuracy of air pressure control of the air bag is lowered, there arises a problem that the accuracy of adjusting the hardness of a sheet containing the air bag is also lowered.
The error due to the instability of the air pressure described above varies depending on, for example, variations in characteristics of tubes, valves, etc. that form the air flow path from the pump to the air bag. However, there is a further problem in detecting air pressure during operation of the pump.

  The present invention has been made in view of such problems, and an object of the present invention is to accurately control the air pressure of the air bag of the seat.

  The invention for solving the above-mentioned problems is a second time operation after a pressure sensor for detecting an air pressure of an air bag provided in a seat and a pump for supplying air to the air bag stop for a first time. A first control circuit that performs control for repeating the intermittent operation, and the pressure sensor detects the air pressure of the air bag during the first time when the pump is stopped, and the detected pressure of the air bag A second control circuit that performs control for the pump to repeat the intermittent operation until the air pressure of the air bag reaches the target pressure in accordance with a differential pressure with respect to the target pressure. is there.

  According to the present invention, the air pressure of the air bag of the sheet can be controlled with high accuracy.

It is a perspective view which shows the structural example of a sheet | seat. It is a block diagram which shows the structural example which manages control of a pneumatic control apparatus, and the structural example of various apparatuses. It is a block diagram which shows the structural example of a microcomputer. It is a graph which shows the structural example of the parameter data which matches the detection pressure of an air bag, the differential pressure | voltage of the detection pressure and target pressure, and the ON time of the pump in intermittent operation | movement of a pump. It is a flowchart which shows an example of the process sequence of the microcomputer core of the pneumatic control apparatus in the case of pneumatic control. It is a time diagram which shows an example of the time change of the operation | movement of a pump and a pressure sensor in the case of air pressure control, and the air pressure of an air bag.

  At least the following matters will become apparent from the description of the present specification and the accompanying drawings.

=== Configuration of pneumatic control device ===
A configuration example of the pneumatic control device 41 of the present embodiment will be described with reference to FIGS. 1 to 4. 1 is a perspective view showing a configuration example of the seat 10, FIG. 2 is a block diagram showing a configuration example for controlling the air pressure control device 41 and configuration examples of various devices, and FIG. 3 is a microcomputer. FIG. 4 is a block diagram showing a configuration example of 71, and FIG. 4 shows the detected pressure of the air bags 30, 31, 32, 33, the detected pressure and the target pressure, and the ON time of the pump 42 in the intermittent operation of the pump 42. It is a graph which shows the structural example of the parameter data which matches.

  As illustrated in FIG. 1, the air pressure control device 41 is provided together with the pump 42 and the valve unit 43 on the lower side of the seat cushion portion 20 of the seat 10 provided in a driver's seat such as a vehicle, for example. A controller 40 operated by a user (for example, a driver) is provided on the left side surface of the seat cushion portion 20 to adjust the air pressure of the air bags 30, 31, 32, and 33 in each part such as a shoulder and a waist. Is provided.

  The seat 10 according to the present embodiment includes a seat cushion portion 20, a seat back portion 21, and a headrest portion 22. Among these, the seat cushion part 20 incorporates an air bag 30 for adjusting the hardness of the seating surface, and the seat back part 21 is provided with air bags 31a and 31b ("air bags" symmetrically with respect to the center in the width direction. 31 ”and air bags 32a and 32b (collectively referred to as“ air bags 32 ”) and air bags 33a and 33b (collectively referred to as“ air bags 33 ”) in the center in the width direction. To do. Here, the air bag 31 is provided to support the user's side, and is composed of an air bag 31a provided on the left side of the sheet from the center of the seat back portion 21 and an air bag 31b provided on the right side of the sheet. The The air bag 32 is provided to support the shoulder of the user, and includes an air bag 32a provided on the left side of the sheet from the center of the seat back portion 21 and an air bag 32b provided on the right side of the page. The air bag 33 is an air bag provided to support the user's waist, and includes an air bag 33a provided on the upper side of the seat back portion 21 and an air bag 33b provided on the lower side. . By adjusting the air pressure of the air bladder 33, a so-called lumbar support function is realized.

  As illustrated in FIG. 2, the air pressure control device 41 includes a pressure sensor 70, a microcomputer 71, and a drive circuit 72. The air pressure control device 41 is, for example, an ECU (Electronic Control Unit), and the pump 42 and the valve unit 43 are controlled according to the operation result of the controller 40 by the user, the pressure detected by the pressure sensor 70, and the like. Control the behavior.

  The pressure sensor 70 is a single sensor for detecting the air pressure of each of the air bags 30, 31, 32, and 33 and includes a pressure receiving unit (not shown) for detecting the pressure.

  The microcomputer 71 is a microcomputer core (first control circuit, second control circuit) to be described later for overall control of the air pressure control device 41 according to the operation result of the controller 40 by the user, the pressure detected by the pressure sensor 70, and the like. Control circuit) 102. For example, when an input signal from the controller 40, a detection signal from the pressure sensor 70, or the like is received, the drive circuit 72 and the pump 42 are controlled based on these signals. A signal is transmitted.

  The drive circuit 72 is a circuit that controls the opening and closing of each valve by driving the valve unit 43 based on a control signal from the microcomputer 71.

  Hereinafter, a configuration example of the valve unit 43 and the pump 42 that are controlled by the air pressure control device 41 and the controller 40 that is an input terminal to the air pressure control device 41 will be described.

  As illustrated in FIG. 2, the valve unit 43 includes control valves 90, 91, 92, 93, 94 and exhaust valves 95, 96, 97 for controlling intake and exhaust of the air bags 30, 31, 32, 33. It has.

  The control valve 90 is, for example, a solenoid valve for connecting or blocking the tube 80 connected to the pump 42 and the pressure sensor 70 and the shoulder air bag 32. The control valve 90 is connected in the open state and blocked in the closed state. It is like that. Similarly to the control valve 90, the control valves 91, 92, 93, 94 also connect or block the tube 80, the side air bag 31, the waist air bag 33, and the cushion air bag 30. It is like that.

  The exhaust valve 95 is, for example, a solenoid valve for connecting or blocking the tube 80 and the exhaust port 81 for exhausting air, and is connected in the open state and blocked in the closed state. For example, by opening the exhaust valve 95, all the air in the air bags 30, 31, 32, 33 connected to the tube 80 is exhausted from the exhaust port 81. Similarly to the exhaust valve 95, the exhaust valves 96 and 97 connect or disconnect the exhaust port 82 and the air bags 33a and 33b, respectively. In addition, since the exhaust valves 96 and 97 are provided exclusively for the air bags 33a and 33b, for example, the air bag 33b can be exhausted while inhaling the air bag 33a. This leads to smooth adjustment of the lumbar and reduction of the user's uncomfortable feeling during adjustment.

  As illustrated in FIG. 2, the pump 42 sucks air in the atmosphere and discharges it into the air bags 30, 31, 32, 33 based on a control signal from the microcomputer 71. The mouth is in contact with the atmosphere, and the outlet is connected to the tube 80.

  As illustrated in FIG. 2, the controller 40 is a terminal operated by the user to change the shape of the sheet 10, and transmits information corresponding to the operation result to the microcomputer 71 as an input signal. The controller 40 includes operation switches 60, 61, 62, and 63, a setting switch 64, and position switches 65 and 66.

  The operation switches 60, 61, 62, and 63 are switches for adjusting the air pressures of the shoulder air bag 32, the side air bag 31, the cushion air bag 30, and the waist air bag 33, respectively.

  The setting switch 64 is a switch for storing the air pressure of the air bags 30, 31, 32, 33 of each part that determines the shape of the seat 10. For example, when the setting switch 64 is pressed, the shape of the sheet 10 is stored in the memory 101 built in the microcomputer 71 by pressing one of position switches 65 and 66 described later. Yes.

  The position switches 65 and 66 are switches for reproducing the shape of the sheet 10 stored in the memory 101. For example, when the position switch 65 is pressed, the shape of the sheet 10 stored in the memory 101 in association with the position switch 65 is reproduced. When the position switch 66 is pressed, the shape is correlated with the position switch 66. The shape of the sheet 10 stored in the memory 101 is reproduced.

<<< Details of microcomputer 71 >>>
As illustrated in FIG. 3, the microcomputer 71 of the present embodiment includes a microcomputer core 102, an AD converter 100, the memory 101 described above, and a timer 103.
The microcomputer core 102 is a CPU for overall control of the air pressure control device 41, and implements various functions described below of the air pressure control device 41 by executing processes defined in a program stored in the memory 101. .

  Specifically, the microcomputer core 102 causes the pump 42 to repeat an intermittent operation that operates for a predetermined ON time (second time) after stopping for a predetermined OFF time (first time) based on the program. The processing is executed, and the pressure sensor 70 detects the air pressure of the air bag (for example, the air bag 30) during the OFF time when the pump 42 is stopped, and the pump 42 detects the detected pressure and the target pressure of the air bag. In response to the differential pressure, a process of repeating the intermittent operation until the air pressure of the air bag reaches the target pressure is executed. Further, the microcomputer core 102 continuously operates the pump 42 until the air pressure of the air bag reaches a predetermined pressure (below the target pressure) based on the program, and after the air pressure reaches the predetermined pressure. Is configured to repeat the intermittent operation until it reaches the target pressure. Further, the microcomputer core 102 determines the stabilization time necessary for accurate detection of the air pressure during the passage of the OFF time since the operation of the pump 42 is turned OFF with respect to the pressure sensor 70 based on the program. A process for performing the same detection after the elapse of (third time) is executed. The function of the microcomputer core 102 described above will be described in detail again in the operation description of the pneumatic control device 41 described later.

  The AD converter 100 is a circuit that converts an analog signal output from the pressure sensor 70 into digital data at predetermined intervals and outputs the digital data.

  The memory 101 includes a RAM (Random Access Memory) 110 and a ROM (Read Only Memory) 111. The RAM 110 stores, for example, various data used for the operation of the air pressure control device 41. The ROM 111 includes, for example, a program storage unit 112 that stores a program executed by the microcomputer core 102 and a parameter data storage unit 113 that stores parameter data described below.

  The timer 103 measures the above-described ON time, OFF time, stabilization time, and the like.

  As illustrated in FIG. 4, the parameter data relating to the above-mentioned “ON time” in the intermittent operation of the pump 42 is an air bag (for example, an air bag) detected by the pressure sensor 70 during the OFF time in the intermittent operation of the pump 42. 30) is table data in which information indicating the ON time in the intermittent operation of the pump 42 is associated with information indicating the detected pressure 30) and information indicating the differential pressure between the detected pressure and the target pressure. According to the figure, for example, when the detected pressure is 0 kPa (relative pressure to the atmospheric pressure) and the differential pressure between the detected pressure and the target pressure is 10 kPa, the ON time in the intermittent operation of the pump 42 is set to 500 ms. ing. Here, the differential pressure “A” illustrated in the figure shows a positive value whose absolute value is close to zero (but not zero). Further, the ON time is set longer as both the detected pressure and the differential pressure become higher, while the ON time is set shorter as both the detected pressure and the differential pressure become lower. The parameter data relating to the ON time is generated in advance for each of the air bags 30, 31, 32, 33 based on the experimental results and stored in the parameter data storage unit 113. Here, the ON time can counter the pressure load from the air bag without the air pressure of the air bag (for example, air bag 30) greatly exceeding the target pressure by the intake operation per pump 42, for example. The time is set in advance enough for the torque to be generated in the motor (not shown) of the pump 42. The ON time is set in advance in consideration of the characteristics of the pump 42 and the air bags 30, 31, 32, 33.

  The parameter data (not shown) related to the above-mentioned “OFF time” in the intermittent operation of the pump 42 is information on a fixed value indicating the OFF time, and the experimental results are obtained for each of the air bags 30, 31, 32, 33. Is generated in advance and stored in the parameter data storage unit 113. Here, the OFF time is set in advance to a time that is sufficient for stopping the pump 42 and stabilizing the air flow, and minimizes the outflow of air from the pump 42, for example.

  Further, the parameter data (not shown) related to the above-mentioned “stabilization time” in the intermittent operation of the pump 42 is a fixed value indicating the stabilization time required for the air pressure to stabilize after the operation of the pump 42 is turned off. This is value information, and is generated in advance for each of the air bags 30, 31, 32, and 33 based on the experimental results and stored in the parameter data storage unit 113. In addition, this stabilization time is 40 ms as an example. However, in this case, the OFF time is set to a time longer than 40 ms.

  Further, the parameter data (not shown) related to the above-mentioned “predetermined pressure” that is a reference for switching the continuous operation from the continuous operation of the pump 42 is the optimum air pressure (for example, for executing the air pressure control accurately in a short time) , Which is a fixed value indicating air pressure slightly lower than the target pressure), is generated in advance for each of the air bags 30, 31, 32, 33 based on the experimental results and stored in the parameter data storage unit 113. .

=== Pneumatic controller operation ===
An air pressure control operation by the air pressure control device 41 having the above-described configuration will be described with reference to FIGS. 5 and 6. FIG. 5 is a flowchart showing an example of the processing procedure of the microcomputer core 102 during the air pressure control. FIG. 6 shows the operation of the pump 42 and the pressure sensor 70 and the air pressure of the air bag 30 during the air pressure control. It is a time diagram which shows an example of a time change.

  Hereinafter, as an example, an operation for inhaling the air bag 30 to regenerate the shape of the seat cushion portion 20 of the seat 10 will be described. Here, the shape to be reproduced is specifically stored as the target pressure of the air bladder 30 in the parameter data storage unit 113 of the ROM 111.

  As illustrated in FIG. 5, the microcomputer core 102 first determines whether or not the air bag 30 needs to be sucked (S100). The case where the intake is necessary is, for example, a case where the position switches 65 and 66 of the controller 40 are pressed to regenerate the shape of the seat cushion portion 20.

<<< Continuous operation of pump 42 >>>
When it is determined that the intake is necessary (S100: YES), the microcomputer core 102 transmits a control signal to the pump 42 to start the operation and transmits a control signal to the drive circuit 72 to control the valve unit 43. Only the valve 94 (corresponding to the air bag 30) is opened, and the intake of the air bag 30 is started (S101).

  The microcomputer core 102 transmits a control signal to the pressure sensor 70 to detect the air pressure of the air bladder 30 (S102), and determines whether or not the detected pressure has reached the predetermined pressure (S103). In step S102, since the air bag 30 is inhaling by the pump 42, the pressure detected by the pressure sensor 70 in such a transient state is, for example, that the air pressure is sufficiently stable after the pump 42 stops. An error is included in the accurate air pressure of the air bag 30 detected by the sensor 70. Therefore, in the present embodiment, a correlation between the detected pressure of the pressure sensor 70 when the pump 42 is operating and the detected pressure of the pressure sensor 70 when the pump 42 is stopped is obtained in advance by experiments, and the microcomputer core 102 A correction based on the correlation is applied to the detected pressure during the operation of the pump 42. This correlation is such that the detection accuracy of the pressure sensor 70 becomes lower as the pressure of the detection target is lower, and therefore, for example, with a predetermined detection pressure as a threshold value, the correlation is a linear relationship above the threshold value, but a non-linear relationship below the threshold value. Suppose that Specifically, in the case of a linear relationship, the detected pressure of the pressure sensor 70 when the pump 42 is stopped with respect to the plurality of detected pressures of the pressure sensor 70 when the pump 42 is operating (all are equal to or greater than the threshold). Are obtained in advance by experiments, and for example, two correction coefficients (ie, slope and intercept) representing a linear relationship are obtained in advance by least square calculation. On the other hand, in the case of a non-linear relationship, for example, air pressures less than a threshold value are divided into a plurality of narrow ranges, and one correction amount for the detected pressure is obtained in advance by experiments for each of the plurality of ranges. These correction coefficients and correction amounts are obtained in advance by experiments and calculations for each air bag that is the object of air pressure detection. In the parameter data storage unit 113 of the ROM 111, information indicating a threshold value for each air bag and a value equal to or greater than the threshold value are obtained. Information indicating two correction coefficients for the air pressure and information indicating one correction amount respectively associated with information indicating a plurality of ranges of air pressure less than the threshold are stored in advance. When the microcomputer core 102 compares the detected pressure of the pressure sensor 70 during operation of the pump 42 with a threshold value and determines that the detected pressure is equal to or greater than the threshold value, the microcomputer core 102 applies two correction coefficients to the detected pressure (that is, “ After multiplying by “slope”, “intercept” is added or subtracted). On the other hand, if the microcomputer core 102 determines that the detected pressure of the pressure sensor 70 during operation of the pump 42 is less than the threshold, the microcomputer core 102 sets one correction amount associated with the range corresponding to the detected pressure to the detected pressure. Apply (ie, add or subtract). However, the present invention is not limited to the above. For example, the detected pressure of the pressure sensor 70 may be corrected by only one of the two types of correction means with the above-described threshold as a boundary, or The pressure detected by the pressure sensor 70 may not be corrected.

  As illustrated in FIG. 6, the pump 42 continuously operates while the microcomputer core 102 repeatedly executes the processes of steps S102 and S103, so that the air pressure linearly approaches a predetermined pressure over time. (Inclined dotted line in FIG. 6).

<<< Intermittent operation of pump 43 >>>
As illustrated in FIG. 5, when it is determined that the pressure detected by the pressure sensor 70 has reached a predetermined pressure (S103: YES), the microcomputer core 102 determines the differential pressure between the detected pressure and the target pressure of the air bag 30. The parameter data storage unit 113 of the ROM 111 is referred to, information indicating the ON time of the pump 42 associated with the detected pressure and the differential pressure (see FIG. 4) is read out, and is a fixed value. Information indicating the OFF time of the pump 42 is read (S104), the timer 103 is reset, and time measurement is started (S105).

  The microcomputer core 102 determines whether or not the time t counted from the step S105 by the timer 103 has reached the ON time acquired in the step S104 (S106).

  When it is determined that the time t counted from the step S105 by the timer 103 has reached the ON time (S106: YES), the microcomputer core 102 transmits a control signal to the pump 42 to stop the operation (S107). 103 is reset to start timing (S108). Here, the control valve 94 (corresponding to the air bag 30) in the valve unit 43 is kept open.

  The microcomputer core 102 determines whether or not the time t counted from step S108 by the timer 103 has reached the stabilization time described above (S109).

  When it is determined that the time t counted from step S108 by the timer 103 has reached the stabilization time (S109: YES), the microcomputer core 102 causes the pressure sensor 70 to detect the air pressure of the air bag 30 (S110). Note that the pressure detected by the pressure sensor 70 is stored in the RAM 110 of the memory 101.

  The microcomputer core 102 determines whether or not the time t counted from the step S108 by the timer 103 has reached the OFF time (S111).

  When it is determined that the time t counted from the step S108 by the timer 103 has reached the OFF time (S111: YES), the microcomputer core 102 refers to the RAM 110 of the memory 101, and the detected pressure in the step S110 is the air bag 30. It is determined whether or not the target pressure is reached (S112). Specifically, the microcomputer core 102 determines whether or not the differential pressure between the detected pressure in step S110 and the target pressure of the air bag 30 has reached zero.

  When it is determined that the detected pressure in step S110 has not reached the target pressure of the air bladder 30 (that is, the differential pressure between the detected pressure and the target pressure has not reached zero) (S112: NO), the microcomputer core 102 A control signal is transmitted to the pump 42, and the operation of the pump 42 that has been stopped from step S107 is started (S113). Thereby, the pump 42 operates while the control valve 94 (corresponding to the air bag 30) in the valve unit 43 is kept open. In this state, the microcomputer core 102 executes the process of step S104 again. That is, the microcomputer core 102 obtains a differential pressure between the detected pressure in step S110 and the target pressure of the air bladder 30, refers to the parameter data storage unit 113 of the ROM 111, and associates the detected pressure with the differential pressure. The information indicating the ON time of the pump 42 (see FIG. 4) is read (S104), and the intermittent operation of the pump 42 is continued.

  That is, the microcomputer core 102 determines in step S112 that the detected pressure in the latest step S110 has not reached the target pressure of the air bladder 30 (that is, the differential pressure between the detected pressure and the target pressure has not reached zero). As long as this is done (S112: NO), the intermittent operation of the pump 42 is repeated with the ON time corresponding to the detected pressure and the differential pressure between the detected pressure and the target pressure, and a preset OFF time. As described above, the ON time of the pump 42 associated with the detected pressure of the pressure sensor 70 and the differential pressure between the detected pressure and the target pressure of the air bladder 30 is shortened, for example, as the differential pressure decreases. (See FIG. 4), the ON time of the pump 42 tends to be shortened as the air pressure of the air bag 30 approaches the target pressure. However, the ON time in FIG. 6 is the same regardless of the air pressure for convenience of illustration.

  As illustrated in FIG. 6, the pressure sensor 70 does not detect the air pressure of the air bag 30 during the ON time of the pump 42 in the intermittent operation of the pump 42. Further, during this ON time, the air pressure of the air bladder 30 increases linearly toward the target pressure with the passage of time (inclined solid line in FIG. 6). Since no air pressure is detected during this period, the air pressure represented by the slanted solid line illustrated in FIG. 6 is not an actual detected pressure, but a virtual air pressure for the convenience of understanding the time variation of the air pressure. It shall be.

  Further, in the OFF time of the pump 42 in the intermittent operation of the pump 42, the pressure sensor 70 detects the air pressure of the air bag 30 when the stabilization time has elapsed after switching from the ON state to the OFF state. In this OFF time, the air pressure of the air bag 30 is substantially constant regardless of the passage of time (horizontal solid line in FIG. 6). During this time, since the air pressure is not detected except when the pressure sensor 70 is in the ON operation, the air pressure represented by the horizontal solid line illustrated in FIG. 6 is not the actual detected pressure, but understands the time variation of the air pressure. It is assumed that a virtual air pressure is represented for convenience.

  As illustrated in FIG. 5, when it is determined that the detected pressure in step S110 has reached the target pressure of the air bladder 30 (that is, the differential pressure between the detected pressure and the target pressure has reached zero) (S112: YES). The microcomputer core 102 transmits a control signal to the drive circuit 72 to close the control valve 94 (corresponding to the air bag 30) in the valve unit 43 (S114), and ends the process.

  With the above processing, the intermittent operation of the pump 42 in which the air pressure increases stepwise with time in FIG. 6 is completed, and the air pressure of the air bag 30 reaches the target pressure. Thereby, the shape of the seat cushion part 20 of the seat 10 is reproduced.

  According to the air pressure control device 41 described above, as illustrated in FIG. 6, an intermittent operation is performed in which the pump 42 is operated only for the ON time and then stopped for the OFF time so as to supply air to the air bag 30. By repeating the cycle of causing the pressure sensor 70 to detect the air pressure of the air bag 30 within the OFF time in accordance with the differential pressure between the detected pressure and the target pressure of the air bag 30, air pressure control based on the real-time detected pressure Is done. In particular, the detected pressure when the pump 42 is stopped does not include, for example, errors according to variations in characteristics of the control valve 94, the tube 80, and the like, so the real-time detected pressure by the pressure sensor 70 becomes more accurate. From the above, by this air pressure control, the final air pressure of the air bladder 30 matches the target pressure within the allowable error range. Therefore, the precision of the hardness adjustment of the corresponding seat cushion part 20 in the seat 10 is improved.

  Further, according to the air pressure control device 41, as illustrated in the parameter data of FIG. 4 and step S104 of FIG. 5, each time the above-described cycle is repeated, the ON time of the pump 42 is equal to the detected pressure of the pressure sensor 70. Since the time is updated to the optimum time for the air pressure control according to the detected pressure and the differential pressure of the target pressure, the accuracy of the air pressure control is further improved by the feedback according to such a differential pressure.

  Further, according to the air pressure control device 41, the pump 42 operates through the timer 103 for an ON time optimally set for air pressure control in advance, and stops for an OFF time optimally set for air pressure control in advance. The accuracy of air pressure control of the air bag 30 is further improved.

  Further, according to the air pressure control device 41, as illustrated in FIG. 6, the detection operation of the pressure sensor 70 in the intermittent operation of the pump 42 is delayed from the time when the pump 42 is switched from the ON state to the OFF state. For example, an error in the detected pressure due to air pressure instability can be reduced.

  Further, according to the air pressure control device 41, the air pressure of the air bag 30 is stabilized after the pump 42 is stopped during the time from the switching from the ON state to the OFF state of the pump 42 described above until the detection operation of the pressure sensor 70. Therefore, the detected pressure error due to the instability of the air pressure can be further reduced.

  Further, according to the air pressure control device 41, the pump 42 is continuously operated until the air pressure of the air bag 30 reaches a predetermined pressure, and after the air pressure reaches the predetermined pressure, the pump 42 is repeatedly operated until it reaches the target pressure. By performing the intermittent operation, the air pressure control of the air bladder 30 can be executed accurately in a short time. For example, when the air pressure control is performed by the continuous operation of the pump 42, even if the detected pressure of the pressure sensor 70 is corrected as described above, the detected pressure includes errors such as a correction coefficient and a correction amount. ing. However, in this case, the time required for the air pressure control is shortened by not stopping the pump 42. Therefore, in the present embodiment, until the air pressure of the air bag 30 reaches the above-described predetermined pressure, the pump 42 is continuously operated (rough adjustment) to shorten the time required for air pressure control, and the air pressure of the air bag 30 is reduced to After reaching the predetermined pressure, the pump 42 is intermittently operated (fine adjustment) to perform air pressure control based on more accurate air pressure. This leads to time reduction and accuracy improvement of the pneumatic control.

  The above-described embodiment is intended to facilitate understanding of the present invention and is not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and equivalents thereof are also included.

  In the above-described embodiment, the seat 10 is for a vehicle. However, the seat 10 is not limited to this. For example, the seat 10 may be for a ship or an aircraft.

  The above-described air pressure control is applied to the operation of sucking the air bag 30 to regenerate the shape of the seat cushion portion 20 of the seat 10, but is not limited to this. For example, the air pressure control described above may be applied to the intake operation of each of the other air bags 31, 32, 33, or any two of the plurality of air bags 30, 31, 32, 33 may be applied. The air pressure control described above may be applied to the above intake operation.

DESCRIPTION OF SYMBOLS 10 Seat 20 Seat cushion part 21 Seat back part 22 Headrest part 30 Air bag 31, 31a, 31b, 32, 32a, 32b, 33, 33a, 33b Air bag 40 Controller 41 Pneumatic controller 42 Pump 43 Valve units 60, 61, 62, 63 Operation switch 64 Setting switch 65, 66 Position switch 70 Pressure sensor 71 Microcomputer 72 Drive circuit 80 Tube 81, 82 Exhaust port 90, 91, 92, 93, 94 Control valve 95, 96, 97 Exhaust valve 100 AD converter 101 Memory 102 Microcomputer core 103 Timer 110 RAM
111 ROM
112 Program storage unit 113 Parameter data storage unit

Claims (6)

A pressure sensor for detecting the air pressure of the air bag provided inside the seat;
A first control circuit that performs control for repeating an intermittent operation that operates for a second time after the pump that supplies air to the air bag stops for a first time;
The pressure sensor detects the air pressure of the air bag during the first time when the pump is stopped, and the air pressure of the air bag is determined according to the differential pressure between the detected pressure of the air bag and the target pressure. A second control circuit for controlling the pump to repeat the intermittent operation until a target pressure is reached;
A pneumatic control device comprising: The pneumatic control device according to claim 1, wherein the second time is a time that increases as a differential pressure between the detected pressure of the air bag and the target pressure increases. The pneumatic control apparatus according to claim 1, wherein the first control circuit includes a timer that counts the first and second times for the pump to repeat the intermittent operation. The air pressure control device according to claim 1, wherein the pressure sensor detects an air pressure of the air bag at a third time in the course of the first time. The air pressure control device according to claim 4, wherein the third time is a time required for the air pressure of the air bag to stabilize. The pump continuously operates until the air pressure of the air bag reaches a predetermined pressure lower than the target pressure, and when the air pressure of the air bag reaches the predetermined pressure, the air pressure of the air bag reaches the target pressure. The pneumatic control apparatus according to any one of claims 1 to 5, wherein the intermittent operation is repeated by the first and second control circuits.

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