JPH0567448B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a seat cushion thigh support device for optimally adjusting the seating condition on the seat cushion.

[Problems to be solved by conventional technology and invention]

An example of this type of device is a device that changes the inclination angle of the entire seat cushion. However, in this case, increasing the inclination angle may put pressure on the abdomen or cause numbness in the legs due to pressure on the backs of the knees. Additionally, a device that moves only the front edge of the seat cushion up and down is well known, but it similarly tends to cause numbness in the legs due to localized pressure.

Furthermore, it is usually difficult to optimally adjust the thigh support in a static condition immediately after riding a car, and if you feel discomfort after riding for a while and try to readjust it, This poses a problem as the occupants no longer have the sensitivity to adjust to the optimal support. Therefore, it is desirable to automatically set the optimal thigh support for occupants of all body types during dynamic driving conditions.
Conventionally, such a device did not exist.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a thigh support device for a seat cushion that automatically provides optimum support depending on the body shape and seating position.

(Means for Solving the Problems) In order to achieve this object, the present invention, as shown in FIG.
A rotary body 3 which is rotationally driven by a motor 4 and has a cam surface eccentric to a horizontal axis of rotation to change the state of protrusion with respect to a horizontal plane is accommodated in the left-right direction via a cushion material. In addition, seat pressure sensors 2 to 2c are installed at at least four locations on the front, rear, left, and right sides of the surface portion of the seat cushion 1 in the central portion.
was placed. As can be seen from FIG. 2, the central portion of the seat cushion 1 corresponds in position to the thigh between the back of the knee 1a and the ischial tuberosity 1b. in this case,
Since the feeling in the thigh becomes duller as you move from the back of the knee 1a toward the ischial tuberosity 1b, it is particularly preferable to place the thigh near the ischial tuberosity 1b as indicated by the circle 1c in the figure.

Then, sensor selection means 5 selects the one with the maximum sitting pressure among the sitting pressure sensors 2 and 2a on the left side, and sensor selection means 5 selects the one with the maximum sitting pressure among the sitting pressure sensors 2b and 2c on the right side. means 5a and determining whether or not each of the two sensors selected by these sensor selection means is within a predetermined seating pressure range, and generating a motor control signal when at least one sensor is outside the range; Seating pressure determination means 6
and when the selection state of the selection means 5, 5a remains unchanged for a predetermined period of time or longer, and the seat pressure determining means 6 determines that it is outside the range for a predetermined period of time or more, a timer means outputs a motor control signal. 7 and a motor drive means 8 for driving the motor 4 by inputting the timed motor control signal.

(Function) The sensor selection means 5 selects the sitting pressure sensor, for example 2, which has a relatively higher sitting pressure among the sensors 2 and 2a on the left side.
Suppose you select . As a result, the seating pressure determining means 6
It is determined whether the sitting pressure levels detected by both of the selected sitting pressure sensors 2 and 2b are within a predetermined sitting pressure range. The clock means 7 is connected to the sensor selection means 5, 5.
When a predetermined period of time has elapsed after the new selection of a, and the seat pressure determining means 6 continues to determine that at least one of them is out of range for a predetermined period of time or more, a motor control signal is supplied to the motor driving means 8.

As a result, the rotating body 3 rotates, so that
The amount of protrusion on the surface of the rotating body for each position of the thigh is changed, and when the sitting pressure determining means 6 determines that the detection signal levels of both sitting pressure sensors are within the allowable range,
The output of the motor control signal is interrupted, so that the rotating body 3 is stopped within the optimum position range. Due to the presence of the timer 7, the rotating body 3 does not respond to temporary fluctuations in seating pressure caused by acceleration or deceleration of the vehicle, traveling on a changing slope, or movement of the seated person's body.

(Example of the invention) 3 to 5 show one embodiment of the present invention.

As shown in FIG. 3, the seat cushion 11
has a cushion material 11 inside the cover 11a.
b, and further has an S spring 16 partially on the back surface thereof.
A seat pan 16 having a shape is arranged and configured. A notch 16b is formed in the seat pan 16 at a position approximately corresponding to the thigh near the ischial bone, and the surface of the cam-shaped rotating body 13 having the same cross section in the left-right direction protrudes from this notch, and its rotating shaft 1
Both sides of 3a are pivotally supported by the side surfaces of the seat pan 16. A gear 13b is provided at one end of the rotating shaft 13a.
is attached and meshed with a worm gear 14a rotated by the motor 14. Cushion material 11b
The thickness of the rotating body 13 is about 40 mm, the hardness is about 16 kg, and the cross-sectional shape of the rotating body 13 has a maximum height of about 15 mm, which changes the seating pressure by several tens of g/ ^cm2 , and its longitudinal position is about 40 mm. It is formed to adjust the degree.

That is, in FIG. 7a, in order not to interfere with each other, the trough A ₀ with weak supporting force, the neutral peak B ₀ ,
A strong peak B ₁ and a very strong peak B ₂ are formed, and the valley A ₀ does not protrude from the seat pan 16 at the position shown in the figure. In all other rotational positions, they all protrude, and each peak exhibits the trajectory shown in FIG. 7b, roughly covering the area shown by hatching.

Incidentally, the mountain portion _B3 is a neutral for supporting the front side.

Furthermore, an acceleration sensor 17 is provided in the seat pan 16.
and an attached circuit unit 1 having the circuit configuration shown in FIG.
8 is stored. On the back surface of the cover 11a of the seat cushion 11, seat pressure sensors 12 to 12c made of, for example, pressure-sensitive conductive rubber are affixed to four locations on the front and back of the rotating shaft 13a and on the left and right along this axis (fourth (see figure). An up/down type manual operation switch 24 is attached to the side of the seat back 15 to manually adjust the seating pressure, and has an off neutral position that automatically returns.

FIG. 5 shows the configuration housed in the attached circuit unit 18. The microcomputer 20 includes A/D converters 21 to 21c which input detection signals from the seat pressure sensors 12 to 12c, and detection signals from the acceleration sensor 17. A/D converter that receives a signal as input;
21d, the timer 22 for counting 10 seconds causes the motor 14 to rotate forward or reverse depending on the setting of the manual operation switch 24 to the up position or down position, and furthermore, the motor 14 is rotated in either direction by being supplied with a motor control signal. A motor drive circuit 23 for rotating in the direction is attached.

The microcomputer 20 performs the following operations according to the program stored in the built-in ROM.
That is, the digitized detection signals of the sitting pressure sensors 12 to 12c are taken in, and the one with the higher detection signal level is identified among the left sitting pressure sensors 12 and 12a. Similarly, the right seat pressure sensors 12b and 12
The one with the higher detection signal level among c is identified.
Next, the identified seat pressure sensor, for example, the front one
2 and 12b is outside a predetermined seating pressure range, for example, 100 to 150 g/cm ² . Furthermore, the timer 22 is made to measure time from the time when the acceleration detected by the acceleration sensor 17 becomes 0.1G or less, the sensor specific time, and the detection time outside the range, and the same state is detected after 10 seconds have passed. If it continues, the timer signal is taken in and the motor control signal is output to the motor drive circuit 23 while this state continues.

The operation of the thigh support device for the seat cushion 11 constructed as described above will be explained with reference to the flowchart shown in FIG.

If the ignition switch is turned on and the manual operation switch 24 is in the neutral position, for example, if the seat pressure sensors 12 and 12b detect a relatively large seat pressure with respect to those on the same side, Both detection signal levels are 100~
It is determined whether or not it is within the range of 150g/cm ² . If either or both are outside this range,
If the acceleration remains below 0.1G for 10 seconds or more, a motor control signal is output to the drive circuit to rotate the rotating body 13 and open the notch 16b of the seat pan 16.
The amount of protrusion and the state of the protrusion are changed. As a result, the sitting pressure on the thigh near the ischial bone, which occupies the position indicated by the dotted line in FIG. 3, changes. When the signal levels of both seat pressure sensors 12, 12b fall within the predetermined range, the motor control signal disappears, and thigh support is performed at that position.

In such an operation, the maximum seating pressure is normally determined by the front sensor pair 12, 12b or the rear sensor pair 1.
This is a combination of 2a and 12c. Due to variations in body shape and sitting position, the change in sitting position from front to back is usually approx.
30 mm, and this range is sufficient to automatically provide optimal support, especially when the seat belt is worn.

By operating the manual operation switch 24 from the neutral position to the up or down position, the rotating body 13
The upheaval state can be set in a desired rotational direction, and the automatic setting operation is interrupted during this time.

In addition, in the above-mentioned embodiment, the detection signal level is
Depending on whether the pressure is above or below the specified seating pressure range,
It is also conceivable to generate a motor control signal that also instructs the rotation direction of the motor 14 by checking the shape of the rotating body 13 stored in a memory. The number of seating pressure sensors can be increased to four or more, and it is also conceivable that the rotating body 13 is separated into left and right parts and controlled independently by the left and right seating pressure sensors.

(Effects of the Invention) As described above, according to the present invention, optimum thigh support is automatically provided according to the body shape and seating position of the occupant just by sitting down, preventing posture collapse by preventing forward slipping, and improving posture while driving. It eliminates pressure on the abdomen and back of the knees, suppressing numbness and fatigue.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a thigh support device for a seat cushion according to the present invention, FIG. 2 is a diagram for explaining the same invention, and FIG. 3 is a diagram showing a thigh support device for a seat cushion according to an embodiment of the present invention. 4 is a plan view showing the mechanical structure of the same cushion portion, FIG. 5 is a view showing the structure of the attached circuit of the same embodiment, and FIG. 6 is the same embodiment. A flowchart for explaining the operation of the example and FIGS. 7a and 7b are diagrams for explaining the structure and operation of the rotating body of the same example, respectively. 1, 11... Seat cushion, 2-2c, 1
2 to 12c... Seat pressure sensor, 3, 13... Rotating body, 11b... Cushion material, 4, 14... Motor.

Claims (1)

[Scope of Claims] 1. A rotating body is housed on the back surface of the cushion material in the central part of the seat cushion, and is rotatably driven by a motor with a rotation axis in the left-right direction, and is provided with a cam surface that changes the raised state. Sensor selection means for arranging seat pressure sensors at at least four locations on the front, rear, left, and right sides of the seat cushion surface in the central portion, and selecting the one that detects the maximum seat pressure among the seat pressure sensors on the left side; a sensor selection means for selecting one of the sitting pressure sensors on the right side that detects a maximum sitting pressure, and each of the two sitting pressure sensors selected by these sensor selection means is within a predetermined sitting pressure range. and a selection state of the selection means remains unchanged for a predetermined period of time, and one or both of the sitting pressure sensors by the sitting pressure determining means are outside the range. A thigh support device for a seat cushion comprising: a timer for outputting a motor control signal when the determination continues for the predetermined time or more; and a motor drive means for driving the motor by inputting the motor control signal. 2. The seat cushion according to claim 1, which is provided with an acceleration sensor and includes motor control interrupting means for interrupting the supply of the motor control signal to the motor drive circuit when the detection signal level exceeds a predetermined level. Thigh support device.