seat

Abstract

To provide a seat capable of easily determining a posture of an occupant in a seated state.SOLUTION: A seat comprises: a plurality of air cells arranged in a row state in a height direction in a seat back; an air pump and a valve unit for supplying fluid into the plurality of air cells; a pressure sensor 33 for detecting an air pressure in each of the plurality of air cells; and an ECU 50 for, after an occupant is seated on the seat back, controlling an electric motor 41a for an air pump and an electromagnetic valve 42a included in the valve unit so as to compress the air cells until a pressure detected by the pressure sensor 33 reaches a prescribed value. The ECU 50 has a posture determination part 51 for determining a posture of the occupant seated on the seat back, on the basis of a time period required until the pressure reaches the prescribed value since compression of the plurality of air cells is started.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a seat having a seat back.

Background Art

[0002] Conventionally, a vehicle seat having a seat back with a plurality of airbags incorporated therein has been known (see, for example, Patent Document 1). In the seat described in Patent Document 1, air is introduced into the plurality of airbags in advance before the occupant gets on the vehicle, and the plurality of airbags are each set to a predetermined airbag state. Then, according to the change state of the internal pressure of the airbag when the occupant sits down in this state, a seat shape that does not impose a burden on the occupant is selected.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Therefore, the objective is to provide a seat that can easily determine the posture of a person while they are seated.

Means for Solving the Problems

[0005] One aspect of the present invention is a seat including a support surface that supports a human back and having a posture determination unit that determines the posture of a person supported by the support surface, including a pad disposed inside the support surface, and a plurality of fluid bags arranged in a row in the height direction in the seat so as to press a person through the support surface. The plurality of fluid bags include a plurality of first fluid bags disposed on the front side of the pad and a plurality of second fluid bags disposed on the rear side of the pad. Each of the multiple first fluids is arranged in two rows, left and right.

Effects of the Invention

[0006] According to the present invention, the posture of a person while seated can be easily determined without requiring a waiting period before the person sits down. [Brief explanation of the drawing]

[0007] [Figure 1] A perspective view showing a schematic configuration of a sheet according to the first embodiment of the present invention. [Figure 2] Figure 1 is a perspective view schematically showing the main components of the sheet frame that makes up the sheet. [Figure 3] A cross-sectional view schematically showing the arrangement of air cells within the seatback of Figure 1. [Figure 4] This figure shows a modified example of Figure 3. [Figure 5] A block diagram showing the configuration of an air control device used in a seat according to the first embodiment of the present invention. [Figure 6] A flowchart showing an example of the process performed by the ECU in Figure 5. [Figure 7] A flowchart showing a modified example of Figure 6. [Figure 8] A front view showing the arrangement of air cells used in a sheet according to a second embodiment of the present invention. [Figure 9] A cross-sectional diagram of a seat back showing the positional relationship of air cells of different shapes used in a seat according to the third embodiment of the present invention. [Figure 10] A perspective view showing the arrangement of multiple air cells used in a sheet according to the third embodiment of the present invention. [Figure 11] A block diagram showing the main components of an air control device used in a seat according to a third embodiment of the present invention. [Figure 12] A cross-sectional view showing the main components of a seat cushion, which is a modified example of the present invention. [Figure 13] Figure 12 is a perspective view showing the configuration of the planar member and the structure. [Figure 14] This figure shows a modified version of Figure 1. [Figure 15] A front view of a pressurizing mechanism built into a sheet, which is a modified example of the present invention. [Figure 16] Figure 15 shows a cross-sectional view of the pressurizing mechanism.

Best Mode for Carrying Out the Invention

[0008] -First Embodiment- Hereinafter, referring to FIGS. 1 to 7, the first embodiment of the present invention will be described. The seat according to the first embodiment is configured as, for example, a vehicle seat provided in the driver's seat or the passenger seat of a vehicle. Note that the seat according to the first embodiment can also be used as a seat for other vehicles, and can also be used other than a vehicle seat. Therefore, the person sitting on the seat is not limited to a passenger.

[0009] FIG. 1 is a perspective view showing a schematic configuration of a seat 100 according to the first embodiment of the present invention. As shown in FIG. 1, the seat 100 has a seat cushion 1 that supports the buttocks of the passenger, a seat back 2 that supports the waist and back of the passenger, and a headrest 3 that supports the head of the passenger. Hereinafter, the front-rear direction, the left-right direction, and the up-down direction are defined as shown in the figure based on the passenger sitting on the seat 100, and the configuration of each part will be described according to this definition.

[0010] The seat cushion 1 extends in the front-rear direction and the left-right direction, and has a substantially rectangular shape as a whole when viewed from above. The seat back 2 extends in the up-down direction and the left-right direction, and has a substantially rectangular shape as a whole when viewed from the front. The seat 100 has a seat frame (FIG. 2) inside, and has a urethane resin pad 301 and a skin 302 on the surface of the pad 301 so as to cover the seat frame. The upper surface of the seat cushion 1 and the front surface of the seat back 2 constitute a seating surface 100a on which the passenger sits, and the seating surface 100a is supported by the seat frame via the pad 301 and the skin 302.

[0011] An armrest 5 is rotatably supported on the left side surface of the seat back 2 (for example, on the opposite side of the door). The lower end portions of the seat back 2 (side frames 221 and 222 in FIG. 2) are supported by a pair of left and right reclining mechanisms 6 at the rear end portion of the seat cushion 1 so as to be tiltable in the front-rear direction with a shaft portion 6a extending in the left-right direction as a fulcrum.

[0012] FIG. 2 is a perspective view schematically showing a main part configuration of a seat frame 200 constituting a seat 100 according to a first embodiment of the present invention. As shown in FIG. 2, the seat frame 200 includes a seat cushion frame 210 constituting a skeleton of the seat cushion 1 and a seat back frame 220 constituting a skeleton of the seat back 2. The seat cushion frame 210 has a pair of left and right side frames 211 and 212 extending in the front-rear direction, and a pair of front and rear connecting frames 213 and 214 connecting the side frames 211 and 212 to each other.

[0013] The seat back frame 220 has a pair of left and right side frames 221 and 222 extending in the vertical direction, and a pair of upper and lower connecting frames 223 and 224 connecting the side frames 221 and 222 to each other. The upper connecting frame 223 is formed by bending a pipe member into a substantially U shape, and both ends of the pipe member constitute upper end portions of the side frames 221 and 222. Substantially plate-shaped side frames (side plates 221a and 222a) that are part of the side frames 221 and 222 are joined to both ends of the pipe member. The side plates 221a and 222a are configured to be elongated in the vertical direction and wide in the front-rear direction. A side airbag unit 7 for protecting an occupant during a collision is attached to the left surface of the left side plate 221a.

[0014] A substantially rectangular support plate 225 is disposed in a space between the side frames 221 and 222 and the connecting frames 223 and 224. The support plate 225 constitutes a pressure receiving plate that receives the self-weight from the seating surface 100a of the occupant. The support plate 225 is supported by the seat back frame 220. For example, as shown in the figure, the lower end portion of the support plate 225 is supported by the connecting frame 224 via a support portion 226, and the upper end portion is supported by the connecting frame 223 via a pair of left and right wire-shaped support portions 227. Note that the support plate 225 may be supported by the left and right side frames 221 and 222.

[0015] Multiple air cells 10 (four in the diagram) are arranged vertically on the front surface of the support plate 225. Each air cell 10 is a fluid bag that expands when air is enclosed and compresses when air is released, and is configured in a roughly rectangular shape when viewed from the front. The expansion and compression of the air cells 10 changes the pressing force on the seating surface 100a, which in turn changes the pressurizing force on the occupant. The multiple air cells 10 are referred to as the first air cell 11, the second air cell 12, the third air cell, and the fourth air cell 14, from bottom to top.

[0016] Figure 3 is a schematic cross-sectional view showing the arrangement of the air cells 10 within the seat back 2. As shown in Figure 3, the first air cell 11 is positioned corresponding to the lower part of the occupant's lower back, the second air cell 12 is positioned corresponding to the upper part of the lumbar spine, the third air cell 13 is positioned corresponding to the lower part of the thoracic spine, and the fourth air cell 14 is positioned corresponding to the upper part of the thoracic spine. Furthermore, the seat 100 is equipped with seating sensors 31 on the seat cushion 1 and the seating surface 100a of the seat back 2 to detect whether or not an occupant is seated.

[0017] Multiple air cells 11-14 are positioned between the support plate 225 and the front plate 228. The front plate 228 is made of a flexible material (e.g., resin) that is less rigid than the support plate 225. The front plate 228 deforms due to the expansion and contraction of the air cells 10, changing its shape in side view, i.e., its curved shape. As a result, the pad 301 is pressed forward via the front plate 228, and a pressing force is applied to the seating surface 100a. The pressing force can also be increased by adding air cells 10 on top of the front plate 228.

[0018] The number and arrangement of the air cells 10 are not limited to those shown in Figure 3. Figure 4 shows a modified example of Figure 3. In the example in Figure 4, three air cells 11 to 13 are arranged in a row in the vertical direction. That is, the first air cell 11 is positioned corresponding to the position of the occupant's pelvis, the second air cell 12 is positioned corresponding to the position of the waist, and the third air cell 13 is positioned corresponding to the position of the shoulder. Note that the front plate 228 in Figures 3 and 4 may be omitted, and the back surface (rear surface) of the pad 301 on the seating surface 100a side may be directly pressed by the air cells 10.

[0019] As shown in Figure 2, an air pump 41 and a valve unit 42 are mounted on the inner surface (right side) of the left side plate 221a. The air pump 41 functions as a source of air (compressed air) supplied to the air cell 10. The air pump 41 is driven by the rotation of an electric motor 41a connected to its rotating shaft, and compressed air is generated by the operation of the air pump 41. Although not shown in the figure, the air pump 41 is covered by a cover member such as a bag or case to suppress the release of operating noise generated when the electric motor 41a rotates (when the air pump 41 is driven), and is mounted on the side plate 221a with its periphery covered by the cover member.

[0020] The valve unit 42 has a plurality of solenoid valves 42a (only one is shown in Figure 5) that control the flow of air supplied from the air pump 41 to each air cell 10. The solenoid valves 42a consist of on / off type solenoid valves that open and close the air passage between the air pump 41 and each air cell 10, and solenoid switching valves that can switch the air inside the air cell 10 to be released to the atmosphere. By driving the solenoid valves 42a, air is supplied to each air cell 10 (pressurized) or air is discharged from each air cell 10 (depressurized). The valve unit 42 has a sensor for measuring internal pressure and a sensor for measuring atmospheric pressure.

[0021] The mounting positions of the air pump 41 and valve unit 42 are not limited to those shown in Figure 2. For example, the air pump 41 and valve unit 42 may be mounted on the outer surface (left side) of the side plate 221a. Alternatively, the air pump 41 and valve unit 42 may be mounted on the inner or outer surface of the right side plate 222a.

[0022] The airflow to each air cell 10 is controlled by an air supply control device. Figure 5 is a block diagram showing the configuration of an air control device 30 used in a seat 100 according to the first embodiment of the present invention. As shown in Figure 5, the air control device 30 includes an electronic control unit (ECU) 50, seat sensors 31 (Figure 3) connected to the ECU 50, a mode selection unit 32, a pressure sensor 33, an electric motor 41a (Figure 2), and an electromagnetic valve 42a (Figure 2). Although not shown in the figures, the air control device 30 further includes a sensor for measuring atmospheric pressure (atmospheric pressure sensor), which is also connected to the ECU 50.

[0023] The mode selection unit 32 is configured, for example, by a selection switch operated by the occupant, which is located on the vehicle's control panel. By operating the mode selection unit 32, the occupant can select either the optimal mode or the posture correction mode. The optimal mode controls the pressure state of the seat back 2 to follow the occupant's posture so that the occupant does not feel uncomfortable. The posture correction mode controls the pressure state of the seat back 2 to correct the occupant's posture in order to bring the occupant's pelvis into an appropriate position. The mode selection unit 32 can also be configured by a mobile device such as a smartphone or tablet.

[0024] The pressure sensor 33 consists of multiple pressure sensors 33 (only one is shown in Figure 5) provided for each of the air cells 11 to 14, and detects the air pressure in each of the air cells 11 to 14. The pressure sensors 33 can be provided, for example, connected to each of the air cells 11 to 14, or connected to an air passage communicating with the air cells 11 to 14. The pressure sensors 33 can also be provided by connecting them to the electromagnetic valve 22a. The pressure detected by the pressure sensor 33 is corrected by the atmospheric pressure detected by the atmospheric pressure sensor. That is, atmospheric pressure decreases with increasing altitude, with the atmospheric pressure at ground level being 1. Therefore, when the atmospheric pressure detected by the atmospheric pressure sensor is standard atmospheric pressure, the pressure in the air cells 11 to 14 is controlled using the detected value of the pressure sensor 33 as is. However, if the detected atmospheric pressure falls outside a predetermined range, the detected value of the pressure sensor 33 is corrected according to the atmospheric pressure detected by the atmospheric pressure sensor, and the pressure in the air cells 11 to 14 is controlled using the corrected value.

[0025] The ECU 50 is configured to include a processing unit having a CPU, ROM, RAM, and other peripheral circuits, and is positioned, for example, below or inside the seat cushion 1. The ECU 50 may also be attached to the back surface of the support plate 225. Functionally, the ECU 50 has a posture determination unit 51 and a posture control unit 52.

[0026] The posture determination unit 51 outputs control signals to the electric motor 41a and the electromagnetic valve 42a based on the signal from the pressure sensor 33 to determine the occupant's posture. Specifically, in the initial state where the air cells 11 to 14 are depressurized, when the seating sensor 31 detects that an occupant is seated, the electric motor 41a is driven to operate the air pump 41, and the electromagnetic valve 42a is driven to sequentially pressurize the air cells 11 to 14. That is, the first air cell 11 is pressurized until the pressure inside the first air cell 11 reaches a predetermined value of Pa, then the second air cell 12 is pressurized until the pressure inside the second air cell 12 reaches a predetermined value of Pa, then the third air cell 13 is pressurized until the pressure inside the third air cell 13 reaches a predetermined value of Pa, and then the fourth air cell 14 is pressurized until the pressure inside the fourth air cell 14 reaches a predetermined value of Pa. When pressurizing the second air cell 12, the first air cell 11 may be depressurized before pressurizing, or it may be pressurized without depressurizing. Similarly, when pressurizing the third air cell 13 and the fourth air cell 14, the other air cells may be depressurized before pressurizing, or they may be pressurized without depressurizing.

[0027] The posture determination unit 51 stores in memory the pressurization time obtained by performing the pressurization operation described above, namely the first time t1 required for the pressure in the first air cell 11 to reach a predetermined value of Pa, the second time t2 required for the pressure in the second air cell 12 to reach a predetermined value of Pa, the third time t3 required for the pressure in the third air cell 13 to reach a predetermined value of Pa, and the fourth time t4 required for the pressure in the fourth air cell 14 to reach a predetermined value of Pa. The posture determination unit 51 determines the occupant's posture, namely the neutral posture, which is the occupant's posture before the pressurizing force is applied to the occupant from the seat back 2, according to the difference between these acquired times t1 to t4.

[0028] For example, if the third time t3 and fourth time t4 are longer than the first time t1 and second time t2, the posture determination unit 51 determines that the occupant's posture is hunched over. Conversely, if the first time t1 and second time t2 are longer than the third time t3 and fourth time t4, the posture determination unit 51 determines that the occupant's posture is arched back. On the other hand, if the difference between the first time t1 to the fourth time t4 is small, it determines that the posture is standard (the so-called S-shaped posture). Such determinations can be made, for example, by pre-storing the correspondence between the first time t1 to the fourth time t4 and the occupant's posture in memory and using this correspondence.

[0029] The posture control unit 52 outputs control signals to the electric motor 41a and the electromagnetic valve 42a according to the pressurization mode selected by the mode selection unit 32 and the posture determined by the posture determination unit 51, thereby controlling the occupant's posture. For example, if the optimal mode is selected, the posture control unit 52 calculates a target pressure (referred to as the first target pressure) for each air cell 11 to 14 such that the occupant can easily maintain a neutral posture, that is, the occupant is uniformly supported across the entire seating surface 100a of the seat back 2 while maintaining a neutral posture. Then, the air cells 11 to 14 are pressurized so that the pressure of each air cell 11 to 14 detected by the pressure sensor 33 becomes the first target pressure.

[0030] On the other hand, if the posture correction mode is selected, the posture control unit 52 calculates a target pressure (referred to as the second target pressure) that will bring the occupant's pelvis to a predetermined state stored in memory. Then, it pressurizes each of the air cells 11 to 14 so that the pressure of each air cell 11 to 14 detected by the pressure sensor 33 becomes the second target pressure.

[0031] Figure 6 is a flowchart showing an example of a process executed by the ECU 50 according to a program pre-stored in memory. The process shown in this flowchart is started, for example, when the seating sensor 31 detects that an occupant is seated after the vehicle door has been opened or closed. At the start of control, air cells 11 to 14 are in a depressurized state, and n, which represents the number of air cell 10, is set to 1.

[0032] As shown in Figure 6, first, in step S1, a control signal is output to the electric motor 41a to start the air pump 41, and a control signal is output to the electromagnetic valve 42a to pressurize the nth air cell 10 (any of air cells 11 to 14). In the initial state, n=1, so the first air cell 11 is pressurized first. Next, in step S, the timer starts counting (timing). Next, in step S3, it is determined whether the pressure of the pressurized air cell 10 detected by the pressure sensor 33 has reached a predetermined value of Pa. If the result in step S3 is positive, the process proceeds to step S4; otherwise, it returns to step S2.

[0033] In step S4, the time taken for the pressure of the air cell 10 to reach a predetermined value of Pa from the start of pressurization, i.e., the time t1 to t4 measured by the timer, is stored in memory. Next, in step S5, it is determined whether or not pressurization of all air cells 11 to 14 has been completed. For example, if the 1st air cell 11, 2nd air cell 12, and 3rd air cell 13 have just been pressurized, this is rejected in step S5 and the process proceeds to step S6. In step S6, n is updated by adding 1, and the process returns to step S1. As a result, the 2nd air cell 12 is pressurized after the 1st air cell 11, the 3rd air cell 13 is pressurized after the 2nd air cell 12, and the 4th air cell 14 is pressurized after the 3rd air cell 13. In this case, the pressurized air cells 11 to 13 may be depressurized before the new air cells 12 to 14 are pressurized, or they may be pressurized without depressurizing.

[0034] If affirmed in step S5, the process proceeds to step S7, where the occupant's posture is determined using the first time t1 to the fourth time t4 stored in step S4. For example, it is determined whether the occupant is hunched over, arched back, or in a standard posture. Next, in step S8, the signal from the mode selection unit 32 is read, and the pressurization mode selected by the occupant is determined. If the optimal mode is determined in step S8, the process proceeds to step S9. In step S9, the first target pressure for each air cell 11 to 14 is calculated according to the optimal mode, and a control signal is output to the electromagnetic valve 42a while referring to the detected value of the pressure sensor 33, thereby controlling the pressurization pressure of the air cells 11 to 14 so that the pressure of each air cell 11 to 14 becomes the first target pressure. In other words, the pressurization is adjusted to the optimal pressure. This adjusts the pressing force from the air cells 11 to 14 to the occupant, i.e., the pressurizing force on the occupant, to a value that maintains the occupant's neutral posture.

[0035] On the other hand, if the posture correction mode is determined in step S8, the process proceeds to step S10. In step S10, the second target pressure for each air cell 11-14 is calculated according to the posture correction mode, and a control signal is output to the electromagnetic valve 42a while referring to the detected value of the pressure sensor 33, thereby controlling the pressure applied to the air cells 11-14 so that the pressure of each air cell 11-14 becomes the second target pressure. In other words, the pressure is adjusted in the posture correction mode. This adjusts the pressing force from the air cells 11-14 to the occupant, i.e., the pressure applied to the occupant, to a value that puts the pelvis in the correct position.

[0036] In Figure 6, the first time t1 to the fourth time t4, until the pressure in air cells 11 to 14 reaches a predetermined value of Pa, is measured, and the neutral posture of the occupant is determined using these times t1 to t4. However, the method for determining the neutral posture is not limited to this. Figure 7 is a flowchart of a modified version of Figure 6. Note that the same parts as in Figure 6 are denoted by the same reference numerals. In Figure 7, after the pressurization of the nth air cell 10 begins and the timer count starts (steps S1 and S2), the process proceeds to step S11 to determine whether a predetermined time ta has elapsed. The predetermined time ta is set to a time shorter than, for example, the time required for air cells 11 to 14 to be fully pressurized. If affirmed in step S11, the process proceeds to step S12; otherwise, the process proceeds to step S2.

[0037] In step S12, the pressure of the pressurized air cell 10 at a predetermined time ta, as detected by the pressure sensor 33, is stored in memory. As a result, the memory sequentially stores the pressurized pressure of the first air cell 11 (first pressure P1), the pressurized pressure of the second air cell 12 (second pressure P2), the pressurized pressure of the third air cell 13 (third pressure P3), and the pressurized pressure of the fourth air cell 14 (fourth pressure P4). In step S13, the occupant's posture (neutral posture) is determined using the first pressure P1 to the fourth pressure P4 stored in step S12.

[0038] For example, if the first pressure P1 or second pressure P2 is greater than the third pressure P3 or fourth pressure P4, it is determined that the occupant is hunched over. Conversely, if the third pressure P3 or fourth pressure P4 is greater than the first pressure P1 or second pressure P2, it is determined that the occupant is arching their back. On the other hand, if the difference between the first pressure P1 to the fourth pressure P4 is small, it is determined that the occupant is in a standard posture. The posture can be determined by, for example, pre-memorizing the correspondence between the pressure of each air cell 11 to 14 and the posture, and using this correspondence.

[0039] According to the first embodiment, the following effects can be achieved. (1) The vehicle seat 100 has a seat back 2 that supports the occupant's waist and back (Figure 1). The seat 100 includes a plurality of air cells 11 to 14 arranged in rows in the height direction within the seat back 2 so as to pressurize the occupant via a support surface that supports the person's back, i.e., the seating surface 100a of the seat back 2; an air pump 41 and a valve unit 42 that supply air to the interior of each of the air cells 11 to 14 and pressurize each of the air cells 11 to 14 individually; a pressure sensor 33 that detects the air pressure in each of the air cells 11 to 14; and an ECU 50 that controls the air pump 41 (electric motor 41a) and the valve unit 42 (solenoid valve 42a) to pressurize the air cells 11 to 14 until the pressure detected by the pressure sensor 33 reaches a predetermined value Pa or a predetermined time ta has elapsed after the occupant sits on the seat back 2 (Figures 2, 5). The ECU 50 has a posture determination unit 51 that determines the posture of the occupant seated on the seat back 2 based on the time required from the start of pressurization of the multiple air cells 11 to 14 until the pressure detected by the pressure sensor 33 reaches a predetermined value of Pa (first time t1 to fourth time t4), or the pressure detected by the pressure sensor 33 after a predetermined time ta has elapsed (first pressure P1 to fourth pressure P4) (Figure 5).

[0040] With this configuration, there is no need to pre-set the pressure in multiple air cells 11-14 to a predetermined value, and the occupant's posture can be determined after the occupant is seated. Therefore, the occupant does not need to wait without being seated until the preparatory actions for posture determination are complete, thus reducing inconvenience for the occupant during posture determination.

[0041] (2) The seat 100 further includes a posture control unit 52 for changing the pressure applied to the seating surface 100a based on the posture of the occupant determined by the posture determination unit 51 (Figure 5). This allows for appropriate control of the occupant's posture.

[0042] (3) The ECU 50 controls the air pump 41 and valve unit 42 so that the inside of the multiple air cells 11 to 14 becomes depressurized before pressurization is started by the operation of the air pump 41 and valve unit 42 after the occupant is seated. As a result, each air cell 11 to 14 is depressurized in the initial state before pressurization is started, and the attitude determination process can start immediately after the occupant is seated.

[0043] (4) Multiple air cells 11-14 filled with air are used as fluid bags for pressurizing the occupants (Figure 2). This makes it easy to construct the fluid bags for pressurization and allows the pressurization unit to be easily built into the seat back 2.

[0044] -Second Embodiment- A second embodiment of the present invention will be described with reference to Figure 8. The differences from the first embodiment will be mainly described below. The second embodiment differs from the first embodiment in the configuration of the air cells 10. That is, in the first embodiment, a plurality of air cells 11 to 14 were arranged in a single row in the height direction of the seat back 2, but in the second embodiment, they are configured to be arranged in multiple rows (for example, two rows) in the height direction.

[0045] Figure 8 is a front view showing the arrangement of the air cells 10 on the support plate 225. As shown in Figure 8, the air cells 10 have two rows, four in each row, for a total of eight air cells 11 to 18. These air cells 11 to 18 are each mounted on the front surface of the support plate 225 so as to be expandable and compressible, and the entire unit is formed integrally with the support plate 225. The unitized air cells 11 to 18 in Figure 8 are referred to as the air cell unit AU.

[0046] The multiple air cells 10 specifically include the first air cell 11 and the second air cell 12, which are arranged side by side at the bottom; the third air cell 13 and the fourth air cell 14, which are arranged side by side above air cells 11 and 12; the fifth air cell 15 and the sixth air cell 16, which are arranged side by side above air cells 13 and 14; and the seventh air cell 17 and the eighth air cell 18, which are arranged side by side at the top. The air cells on the right, 12, 14, 16, and 18, are sometimes called the right column air cells 10R, and the air cells on the left, 11, 13, 15, and 17, are sometimes called the left column air cells 10L.

[0047] The air pressure in each of the air cells 11 to 18 is detected by a pressure sensor 33. The configuration of the air control device 30 in the second embodiment is the same as that shown in Figure 5, and each of the air cells 11 to 18 is pressurized based on the pressure detected by the pressure sensor 33, in the same manner as shown in Figures 6 and 7. That is, the posture determination unit 51 sequentially pressurizes the first air cell 11 to the eighth air cell 18, and determines the posture of the occupant seated on the seat back 2 based on the time required from the start of pressurization of the multiple air cells 11 to 18 until the pressure detected by the pressure sensor 33 reaches a predetermined value Pa (first time t1 to eighth time t8) or the pressure detected by the pressure sensor 33 after a predetermined time ta has elapsed (first pressure P1 to eighth pressure P8) (steps S7, S13).

[0048] This posture determination includes not only the height of the occupant's seated position but also the lateral position. Specifically, the posture determination unit 51 simultaneously determines the occupant's lateral torsional posture (whether or not there is torsion) when seated, based on the difference in the detected values ​​of the pressure sensors 33 of the left row air cells 10L and the right row air cells 10R (for example, the first air cell 11 and the second air cell 12, the third air cell 13 and the fourth air cell 14, etc.) which are arranged at the same height.

[0049] Similar to the first embodiment, the attitude control unit 52 controls the pressure applied to the air cells 11-18 according to the occupant's attitude determined by the attitude determination unit 51 and the pressurization mode selected by the mode selection unit 32. In this case, the pressure can be adjusted so that the left and right sides have different pressing forces according to the occupant's torsional attitude determined by the attitude determination unit 51, thereby providing better pressure to the occupant.

[0050] In this second embodiment, the multiple air cells 11-18 have a right row of air cells 10R and a left row of air cells 10L (Figure 8). The pressure sensor 33 detects the pressure of the right row of air cells 10R and the pressure of the left row of air cells 10L acting on the seating surface 100a due to the weight of the occupant. The ECU 50 (attitude control unit 52) ​​changes the pressure applied to the left and right sides of the seating surface 100a based on the pressure of the right row of air cells 10R and the left row of air cells 10L detected by the pressure sensor 33 (for example, the pressure difference between air cells 10R and 10L located at the same height). This makes it possible to apply pressure to the seating surface 100a according to the occupant's left-right twisting posture, improving the occupant's comfort when seated.

[0051] In this case, air is supplied to the left and right air cells 11-18 until the pressure detected by the pressure sensor 33 reaches a predetermined value of Pa, or until a predetermined time ta has elapsed, after the occupant is seated on the seat back 2. The ECU 50 (attitude determination unit 51) then determines the lateral posture of the occupant seated on the seat back 2 based on the time t1-t8 required from the start of pressurization of the multiple air cells 11-18 until the pressure detected by the pressure sensor 33 reaches a predetermined value of Pa, or the pressure P1-P8 detected by the pressure sensor 33 after the predetermined time ta has elapsed. Therefore, not only the occupant's posture in the height direction but also their torsional posture can be appropriately determined.

[0052] In the second embodiment, the left row air cells 10L and the right row air cells 10R are unitized together with the support plate 225 as an air cell unit AU (Figure 8). This allows the multiple air cells 11 to 18, which are arranged separately on the left and right sides, to be easily incorporated into the seat back 2.

[0053] -Third Embodiment- A third embodiment of the present invention will be described with reference to Figures 9 to 11. The differences from the first embodiment will be primarily described below. The difference between the third embodiment and the first embodiment lies in the configuration of the air cells. Specifically, in the first embodiment, the occupant's posture determination and subsequent posture control were performed using only the same air cell 10. However, in the third embodiment, separate air cells for posture control are used in addition to the air cell 10. Figure 9 is a cross-sectional view of the main part of the seat back 2 showing the positional relationship between air cell 10 and air cell 20, and Figure 10 is a perspective view of the main part of the seat 100 showing the arrangement of multiple posture control air cells 20. In Figure 10, the arrangement of air cells 11 to 14 is shown by dotted lines.

[0054] As shown in Figure 9, the air cell 20 is smaller than the air cell 10 and is positioned in front of the pad 301. More specifically, the air cell 20 is interposed between the pad 301 and the surface 302. By positioning the air cell 20 in front of the pad 301 in this way, the pressure from the air cell 20 is easily transmitted to the seating surface 100a, enabling good posture control for the occupant.

[0055] As shown in Figure 10, the multiple air cells 20 within the seat back 2 are separated in the left-right direction and arranged in rows in the height direction. Specifically, the multiple air cells 20 include a pair of left and right first air cells 21 and second air cells 22 located at the bottom of the seat back 2, a pair of left and right third air cells 23 and fourth air cells 24 located above air cells 21 and 22, a pair of left and right fifth air cells 25 and sixth air cells 26 located above air cells 23 and 24, and a pair of left and right seventh air cells 27 and eighth air cells 28 located above air cells 25 and 26. The right-side air cells 22, 24, 26, and 28 are sometimes called right-row air cells 20R, and the left-side air cells 21, 23, 25, and 27 are sometimes called left-row air cells 20L.

[0056] When viewed from the front, the air cells 20 are positioned so that they overlap with the air cells 10. That is, air cells 21 and 22 overlap with air cell 11, air cells 23 and 24 overlap with air cell 12, air cells 25 and 26 overlap with air cell 13, and air cells 27 and 28 overlap with air cell 14. The arrangement and number of air cells 20 are not limited to those described above. For example, a pair of left and right air cells 20 may be placed above the topmost air cell 14 of the seat back 2.

[0057] The air cells 20 are located not only on the seat back 2 but also on the seat cushion 1. For example, they are arranged in rows in the front-to-back direction, separated into left and right sides, on the underside (bottom) of the upholstery 302 of the seat cushion 1. The air cells 20 on the right side of the seat cushion 1 are sometimes called the right row air cells 29R, and the air cells 20 on the left side are sometimes called the left row air cells 29L. The air cells 29L and 29R of the seat cushion 1 can be used to knead the occupant's thighs. When used for kneading, the air cells 29L and 29R should be periodically pressurized.

[0058] Figure 11 is a block diagram showing the configuration of an air control device 30 used in a seat 100 according to a third embodiment of the present invention. The same reference numerals are used for the same parts as in Figure 5. As shown in Figure 11, the air control device 30, like in Figure 5, includes an ECU 50, a seat sensor 31, a mode selection unit 32, a pressure sensor 33, an electric motor 41a, and a solenoid valve 42a. Furthermore, unlike in Figure 5, it includes a pressure sensor 34 connected to the ECU 50 and a solenoid valve 43a.

[0059] The pressure sensor 34 consists of multiple pressure sensors (only one is shown in Figure 11) provided for each of the air cells 21 to 29, and detects the air pressure in each of the air cells 21 to 29. The electromagnetic valve 43a consists of multiple electromagnetic valves (only one is shown in Figure 11) that control the flow of air supplied from the air pump 41 to each of the air cells 21 to 29, and is incorporated into a valve unit (not shown). This valve unit is positioned, for example, on the inner surface of the side plate 221a, adjacent to the valve unit 42.

[0060] The attitude determination unit 51 determines the occupant's posture by pressurizing the air cells 11-14, similar to the first embodiment. Meanwhile, the attitude control unit 52 controls the occupant's posture by pressurizing the air cells 11-14 and air cells 21-28. More specifically, the attitude control unit 52 calculates target pressures for air cells 11-14 and 21-28, respectively, according to the pressurization mode selected by the mode selection unit 32 and the posture determined by the attitude determination unit 51. Then, while referring to the detected values ​​of the pressure sensors 33 and 34, it outputs control signals to the electric motor 41a and electromagnetic valves 42a and 43a to control the occupant's posture so that the pressures of air cells 11-14 and 21-28 reach the target pressures.

[0061] Furthermore, the air cells 21 to 28 may be sequentially pressurized to determine the occupant's posture. In other words, air cells 21 to 28 can also be used as air cells for posture determination. Since air cells 21 to 28 are located on the left and right sides of the seat back 2, the occupant's posture in the left and right leaning direction can also be detected, as in the second embodiment. In this case, the air cell 10 for posture determination may be omitted. Air cells 21 to 28 may also be used for kneading rather than posture control.

[0062] The above embodiment can be modified into various forms. Several modifications are described below. In the above embodiment, the air pump 41 is located on the seat back 2, but it may also be located on the seat cushion 1. Figure 12 is a cross-sectional view showing the main components of a seat cushion 1 as an example. As shown in Figure 12, the seat cushion 1 has a fabric planar member 101 located below the pad 301 to support the pad 301, and a resin structure 102 located below the planar member 101. The structure 102 is provided to support the planar member 101.

[0063] Figure 13 is a perspective view of the planar member 101 and the structure 102. As shown in Figure 13, the planar member 101 is configured to be approximately rectangular in plan view, with hooks 101a and 101b provided at both its front and rear ends. The structure 102 is formed to correspond to the outer shape of the planar member 101, with hooks 102a and 102b provided at both its front and rear ends. As shown in Figure 12, the hooks 101a and 102a are hooked onto the connecting frame 215 that extends in the left-right direction of the seat cushion frame 210, and the hooks 101b and 102b are hooked onto the connecting frame 214 (Figure 2) at the rear end of the seat cushion frame 210, thereby supporting the planar member 101 and the structure 102 from the seat cushion frame 210.

[0064] An air pump 41 is positioned below the structure 102. The air pump 41 is attached, for example, to the bottom surface of the structure 102 via bolts 41b. One end of an air tube 41c is connected to the air pump 41. The air tube 41c is routed towards the seat back 2 through the gaps in the left and right directions between the hooks 101b and 102b, and compressed air is supplied to the air cell 10 via the air tube 41c. By positioning the air pump 41 on the seat cushion 1 in this way, the air pump 41 can be easily positioned without increasing the size of the seat 100. In addition, since the air pump 41 is positioned away from the occupant's head, the occupant is less likely to notice the operating noise of the air pump 41, improving occupant comfort.

[0065] Figure 14 is a perspective view of seat 100 showing a modified example of Figure 1. In Figure 14, a seat belt 4 is provided on the right side of the seat back 2. The seat belt 4 is a so-called three-point seat belt, supported by the upper end of the seat back 2 on the right side of the headrest 3, and also supported on both the left and right sides of the lower end of the seat back 2. By providing the seat belt 4 on the right side of the seat back 2 in this way, the right side of the seat back 2 is constructed with higher strength than the left side. Therefore, although not shown in the illustration, the left reclining mechanism 6 has a single gear mechanism, while the right reclining mechanism 6 has a pair of gear mechanisms, and the right reclining mechanism 6 is constructed to be larger than the left reclining mechanism 6.

[0066] Therefore, there is more space available on the left side of the seat 100 than on the right side. Consequently, in this case, it is preferable to attach the air pump 41 and valve unit 42 to the left side frame 221 rather than the right side frame 222, as described above (Figure 2). However, when a seat belt 4 is provided on the seat back 2, the layout constraints on the placement of the air pump 41 become greater compared to when a seat belt 4 is not provided (Figure 1), due to the increase in the number of parts attached to the seat back 2 and the larger size of the seat back 2. Considering this point, it is preferable to place the air pump 41 on the seat cushion 1 side, as shown in Figure 12.

[0067] In the above embodiment, the occupants are pressurized by the air cells 10 and 20 after their posture is determined. However, the pressurization of the occupants after posture determination may be performed using a pressurization mechanism other than the air cells 10 and 20. Figure 15 is a front view of an example pressurization mechanism 70, and Figure 16 is a cross-sectional view. As shown in Figures 15 and 16, the pressurization mechanism 70 has a pair of left and right frames (right frame 71, left frame 72) that extend in the vertical direction, and a central frame 73 that extends in the vertical direction and is located between the right frame 71 and the left frame 72 and behind the frames 71 and 72. A movable frame 74 that extends in the left-right direction is located in front of the frames 71 to 73. The pressurization mechanism 70 is located, for example, behind the front plate 228 (Figure 3) and facing the front plate 228.

[0068] The left and right ends of the movable frame 74 engage with frames 71 and 72 via guides 74a and 74b, and the movable frame 74 is supported so as to be movable vertically along the left and right frames 71 and 72. A ball screw 75 extending vertically is rotatably supported on the central frame 73. The ball screw 75 is rotationally driven by a motor 76 attached to the lower end of the central frame 73. A nut 77 provided on the rear surface of the movable frame 74 is screwed onto the ball screw 75. As a result, the movable frame 74 moves vertically in accordance with the rotation of the ball screw 75.

[0069] As shown in Figure 15, the movable frame 74 is provided with a pair of left and right arms 81 that are roughly U-shaped when viewed from the front. The arms 81 extend in the left-right direction, and their left and right inner ends (the left end of the right arm 81 and the right end of the left arm 81) are each supported by the movable frame 74 so as to be rotatable in the front-rear direction. As shown in Figure 16, the arms 81 have inclined portions 81a that are inclined outward and forward in the left-right direction. A pair of left and right movable blocks 82 are arranged on the front side of the movable frame 74. As shown in Figures 15 and 16, the upper and lower ends of the movable blocks 82 engage with the movable frame 74, and the movable blocks 82 are supported so as to be movable in the left-right direction along the front surface of the movable frame 74. An engagement surface 82a is formed on the front surface of the movable block 82, which is inclined inward and rearward in the left-right direction, and the inclined portions 81a of the arms 81 abut against the engagement surface 82a.

[0070] A ball screw 83 extending in the left-right direction is rotatably supported on the movable frame 74. The right end of the ball screw 83 is connected to a motor 84 mounted on the right end face of the movable frame 74, and the ball screw 83 is rotationally driven by the motor 84. The ball screw 83 passes through the movable block 82 in the left-right direction. The movable block 82 is provided with a screw hole 82b, and the ball screw 83 is screwed into the screw hole 82b. The ball screw 83 is configured, for example, with a right-hand thread on the right side and a left-hand thread on the left side.

[0071] When the motor 84 rotates in one direction, the left and right movable blocks 82 move inward in the left and right directions, and the left and right outer ends of the arm 81 move forward as shown by the arrows in Figure 16. As a result, the arm 81 deforms as shown by the dotted line, and the front plate 228 is pushed by the arm 81, increasing the pressure on the occupant. On the other hand, when the motor 84 rotates in the opposite direction, the left and right movable blocks 82 move outward in the left and right directions, and the left and right outer ends of the arm 81 move backward. As a result, the left and right outer ends of the arm 81 move backward, and the pressure on the occupant decreases.

[0072] In the above embodiment, multiple air cells 10, 20 filled with air were used as multiple fluid bags, but other gases or liquids may be sealed in the fluid bags. In the above embodiment, the air cells 10 were pressurized using an air pump 41 and a valve unit 42, but the configuration of the pressurization unit can be any as long as it is possible to pressurize the multiple fluid bags individually. In the above embodiment, the pressure of the air in the multiple air cells 10 was detected by a pressure sensor 33, but the configuration of the pressure detection unit and the first pressure detection unit is not limited to those described above. In the above embodiment, after detecting the seating of an occupant, the ECU 50 controlled the electric motor 41a and the electromagnetic valve 42a to pressurize the air cells 10 until the pressure detected by the pressure sensor 33 reached a predetermined value Pa, or until a predetermined time ta had elapsed, but the configuration of the control unit is not limited to those described above. For example, instead of pressurizing the multiple air cells 10 one by one, they may be pressurized together.

[0073] In the above embodiment, the pressure applied to the air cell 10 is adjusted based on the occupant's posture determined by the posture determination unit 51. However, the configuration of the pressure changing means and the first pressure changing means for changing the pressure applied to the seating surface 100a is not limited to those described above. For example, a pressurizing mechanism 70 (Figures 15, 16) may be used as the pressure changing means. In the above embodiment, when determining the occupant's posture after they are seated, the air cell 10 is started to pressurize from a depressurized state. However, pressurization may be started from a state other than a depressurized state, i.e., without a depressurized state. In the above second embodiment, a plurality of air cells 11, 13, 15 etc. (first fluid bags) arranged in the height direction and a plurality of air cells 11, 12 etc. (second fluid bags) arranged in the left-right direction are attached to a support plate 225 to constitute the air cell unit AU. However, the configuration of the fluid bag unit is not limited to this.

[0074] In the second embodiment described above, the occupant's lateral posture is determined based on the detected values ​​of a pair of left and right pressure sensors 33 (second pressure detection unit) that detect the pressure of the right row air cell 10R and the left row air cell 10L, respectively, and the pressure applied to the left and right sides of the seat surface 100a is changed by adjusting the pressure of the right row air cell 10R and the left row air cell 10L. However, the second pressure changing means is not limited to those described above. In the third embodiment, the pressure sensor 34 that detects the pressure of the left and right air cells 20 may be used as the second pressure detection unit, and the pressure of the right row air cell 20R and the left row air cell 20L may be adjusted as the second pressure changing means.

[0075] In the above embodiment, multiple air cells 10 are used to pressurize the seating surface of the seat back 2 toward the occupant. However, in a seat without a seat back, fluid bags such as air cells may be arranged in rows in the height direction (the direction in which the person's back extends) within the seat to pressurize the support surface that supports the occupant's back toward the person.

[0076] The above description is merely an example, and the present invention is not limited by the embodiments and modifications described above, as long as the features of the present invention are not impaired. It is also possible to arbitrarily combine one or more of the above embodiments and modifications, and to combine modifications with each other. [Explanation of Symbols]

[0077] 1 Seat cushion, 2 Seat back, 10, 20 Air cells, 33 Pressure sensor, 41 Air pump, 42 Valve unit, 50 ECU, 51 Attitude determination unit, 52 Attitude control unit, 100 Seat

Claims

1. A seat having a support surface for supporting a person's back, and a posture determination unit for determining the posture of a person supported by the support surface, The sheet comprises a pad positioned inside the support surface, and a plurality of fluid bags arranged in rows in the height direction within the sheet to apply pressure to a person through the support surface, The plurality of fluid bags comprises a plurality of first fluid bags arranged on the front side of the pad and a plurality of second fluid bags arranged on the rear side of the pad. A sheet characterized in that each of the multiple first fluid bags is arranged in two rows, left and right.

2. In the sheet described in claim 1, The system further includes a support plate that receives the weight of a person via the aforementioned support surface, A sheet characterized in that each of the multiple second fluid bags is provided integrated with the support plate.

3. In the sheet described in claim 1, The system further comprises a pump that delivers fluid to the fluid bag and a valve unit that controls the flow of air supplied from the pump, The seat is characterized in that the pump and the valve unit are attached to the inner or outer surface of a side plate located to the side of the support surface.

4. In the sheet described in claim 3, A seat characterized in that the valve unit is provided on the inner surface of the side plate.

5. In the sheet described in claim 3, The seat is characterized in that the pump and the valve unit are provided between the side airbag unit, which is provided on the left side of the side plate located to the left of the support surface, and the fluid bag.

6. In the sheet described in claim 5, The seat is characterized in that the pump and the valve unit are positioned between the side airbag unit and the left end of the fluid bag.

7. In the sheet described in claim 1, A pump for supplying fluid to the fluid bag and a valve unit for controlling the flow of air supplied from the pump are provided on the inner or outer surface of the side plate located to the side of the support surface. The valve unit is characterized in that it is provided above the pump.

8. In the sheet described in claim 1, A seat cushion that supports a person's buttocks, A seat back having the aforementioned support surface and supported so as to be tiltable in the front-rear direction at the rear end of the seat cushion via a reclining mechanism, A headrest that supports a person's head, A seat further comprising an armrest rotatably supported on the side of the seat back.

9. In the sheet described in claim 3, A seat cushion that supports a person's buttocks, A seat back having the aforementioned support surface and supported so as to be tiltable in the front-rear direction at the rear end of the seat cushion via a reclining mechanism, The seat belt is further supported at the upper end of one side of the seat back in the left-right direction, The seat is characterized in that the pump is provided on a structure supported by the seat cushion frame of the seat cushion.

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