JPS63183016A - Active control seat for vehicle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vehicle seat whose cushioning properties can be varied by adjusting the viscosity of a magnetic fluid incorporated therein.

Prior Art Japanese Patent Application No. 61-287458 discloses means for changing cushioning properties by utilizing magnetic fluid.

This relates to a vehicle seat support device, in which a cylinder made of a non-magnetic material that is fixed to the vehicle body is filled with magnetic fluid, and a permanent magnet is located within the magnetic fluid at a distance from the inner wall of the cylinder. The permanent magnet is fixed to the seat cushion frame via a support rod, and a coil capable of applying a magnetic field to the magnetic fluid is disposed outside the cylinder. The present invention is characterized in that it is connected to a power source controlled by a computer that calculates the required current value based on a detection signal from a sensor such as a throttle position.O Problems to be solved by the invention However, the above-mentioned application The purpose of this adjustment is to adjust the cushioning properties of the seat against the vehicle floor, but not to adjust the cushioning properties at the contact area between the passenger and the seat.

Therefore, it is not possible to control the hardness of the seat cushioning material in accordance with the preferences of the occupant, or in accordance with the driving conditions and driving conditions.

Means for Solving the Problems In order to solve the above problems, the present invention provides an active control seat for a vehicle in which the cushioning properties of the vehicle seat are variable by adjusting the viscosity of a magnetic fluid. A configuration is adopted in which a bag containing a magnetic fluid is installed under the epidermis of the site, and a viscosity adjusting electromagnet is installed adjacent to the bag.

Here, the magnetic fluid is made of, for example, magnetic fine particles such as magnetite (Fe3o4) having a dispersant adsorbed on the surface thereof dispersed in a solvent such as oil or water.

Magnetic fluid has the property of increasing its viscosity when a magnetic field is applied, and the change appears instantaneously.

Now, the viscosity when there is no magnetic field is η5, the viscosity when there is a magnetic field is M, the magnetization of the magnetic particles is M, the strength of the magnetic field is H1, the shear rate of the magnetic fluid is γ, and the viscosity of the solvent is η. The change in viscosity of the magnetic fluid due to the magnetic field is shown by curve A in FIG. 6.

Figure 6 shows the ratio of the viscosity η□ in the presence of a magnetic field to the viscosity ηS in the absence of a magnetic field as a function of γηc)/MH, indicating that the viscosity changes in proportion to the strength of the magnetic field. The present invention utilizes the above-mentioned properties of magnetic fluid.

The magnetic force of the viscosity adjusting electromagnet is controlled by a predetermined control section.

The control unit may be an electric circuit that changes the value of the current flowing through the electromagnet according to an operation by the occupant.

In addition, there are acceleration sensors installed on the car body that detect acceleration in the vertical, longitudinal, and lateral directions of the car body, and the signals from these sensors are used to calculate the current value that should be passed to the electromagnet in a specific part of the seat. The control unit can also be configured with a computer.

Operation: An electromagnet corresponding to a specific part of the bag is energized by a computer that performs calculations and outputs based on the operation of the occupant or information obtained from an acceleration sensor.

The bag body is, for example, the central part of the backrest (lumbar support part),
It is buried under the epidermis of the side support part, hip side support part, and front end.

By the above-mentioned energization, the viscosity of the magnetic fluid in all or any of the bags increases and hardens, or the viscosity decreases and softens, thereby changing the cushioning properties.

Electricity is applied to electromagnets selected by the occupant when the occupant makes adjustments, and energization is conducted by the computer based on acceleration information from each sensor.

For example, when the vehicle body turns to the right, the amount of electricity applied to the left electromagnet can be increased to make the corresponding bag harder, and when the vehicle turns to the left, the right bag can be made harder.

Embodiment An embodiment of the active control sheet according to the present invention will be described with reference to FIGS. 1 to 5.

In these figures, reference numeral 1 indicates a seat cushion of a vehicle seat, and a bag body 6.7.8 in which magnetic fluid 5 is sealed in the hip portion 2, hip side support portion 3, and front end portion 4 of this seat cushion 1 is shown. are installed respectively.

The bag body 6.7.8 is formed into a pillow shape and is made of a soft material such as rubber or synthetic resin.

And a cushioning material 10 made of a skin 9 and a urethane material.
It is installed below.

Seat cushion frame 11 is under the cushion material 10
There is an electromagnet 12, which is slightly smaller than the bags 6, 7.8, on which is installed corresponding to each bag 6.7.8. Each bag body 6, 7.8 has an electromagnet 12 and a cushion material 10
is attached to both sides.

Further, reference numeral 13 indicates a seat back, and bags 16 and 17 filled with magnetic fluid 5 are also installed in the center portion 14 and side port portions 15 of the backrest in the same manner as described above.

The electromagnet 12 is connected to a variable resistor 18 as shown in FIG.
The amount of current supplied is controlled by the variable resistor 18, and the variable resistor 18 is controlled by the computer 19.

The computer 19 includes a sensor 20 that detects acceleration in the vertical direction of the vehicle body, a sensor 21 that detects acceleration in the longitudinal direction,
The amount of current is calculated by obtaining acceleration information from a sensor 22 that detects acceleration in the left and right direction, and outputs the amount to the variable resistor 18.

In response to the output from the computer 19, the variable resistor 18 controls the amount of current applied to the electromagnet 12, thereby changing the viscosity of the magnetic fluid 5, making it harder or softer than before.

Next, control of the magnetic fluid 5 in the bag body 16 of the backrest central portion 14 during sudden acceleration will be explained using the flowchart of FIG.

The acceleration α detected by the acceleration sensor 21 is 2.0 m/
See step 1) to determine whether 2≧α.
If YES, the current is set to O (step 2). As a result, the magnetic field of the electromagnet 12 disappears, and the viscosity of the magnetic fluid 5 in the bag 16 decreases.

If No in step 1, 3.0m/5eC2
≧α is determined (step 3).

If YES, the current is set to 2A (step 4), and a relatively weak magnetic force is generated in the electromagnet 12. Therefore, the magnetic fluid 5 has a medium viscosity and is slightly hardened.

If No, it is further determined whether 4.0 m/sec 2≧α (step 5).

If YES in step 5, the current is increased to 3A (step 6). As a result, the electromagnet 12 generates a moderate magnetic force, and the viscosity of the magnetic fluid 5 increases, making it harder than before.

If No, the current is increased to 4A (step 7). Therefore, the electromagnet 12 further strengthens the magnetic force and increases the hardness of the magnetic fluid 5.

In this way, the hardness of the backrest central portion 140 and the bag body 16 increases in response to an increase in acceleration based on the signal from the sensor 21 that detects the acceleration in the longitudinal direction of the vehicle body.

Although the explanation using a flowchart is omitted, the bags 6, 7, 8, and 17 of the Noh part are also connected to the respective sensors 20, 21.
．． The degree of hardening is changed depending on the signal from 22.

Effects of the Invention Since the present invention has the above-described configuration, the cushioning properties at the contact portion between the occupant and the seat can be adjusted according to the occupant's preference.

Further, the cushioning properties can be automatically adjusted according to road conditions, driving conditions, driving conditions, etc.

Furthermore, in the present invention, since the magnetic fluid is sealed in the bag, a large number of bags can be prepared and installed in various parts of the seat.

Therefore, the cushioning properties can be adjusted differently for each part of the seat. Therefore, it is possible to make adjustments according to the physique of the occupant, or to make only specific parts stiffer when accelerating suddenly, turning sharply, driving on rough roads, or jumping. For example, it is possible to make the bag under the left hip side support harder when turning to the right, and to make the bag under the right hip side support harder when turning to the left.

When starting suddenly or accelerating suddenly, the center of the backrest and hip area can be made stiffer.

When passing through rough roads, the center part of the backrest and the hip part can be made soft, and the side support part and hip side support part can be made hard.

Furthermore, the present invention supports the occupant's body using a magnetic fluid, and since the magnetic fluid generally has a high viscosity and is difficult to flow, it provides an appropriate sense of resistance to the relative movement between the contact area of the body and the seat area. It has a moist feel, so you can rub it with superior comfort.

[Brief explanation of the drawing]

The figure shows one embodiment of the present invention, and FIG. 1 is l-1 in FIG. 3.
2 is an enlarged view of a portion of FIG. 1 showing a device for controlling the hardness of the magnetic fluid, FIG. 3 is a front view of the sheet diagonally from above, FIG. 4 is a perspective view, and FIG. The figure is a flowchart for controlling the hardness of the bag under the center of the backrest based on signals from the longitudinal acceleration sensor, and FIG. 6 is a graph showing the relationship between the viscosity of the magnetic fluid and the magnitude of the current. 1: Seat cushion, 2: Hip part, 3: Hip side support part, 4: Front end part, 5: Side support part, 6.7.8: Bag body, 9: Outer skin, 10: Cushion material, 11: Frame, 12: Electromagnet, 13: Seat pack, 14: Backrest center, 15: Side support, 16.17: Bag, 18: Variable resistor, 19:
Computer, 20, 21, 22: acceleration sensor.

Claims (1)

[Claims] In an active control seat for a vehicle in which the cushioning properties of the vehicle seat are variable by adjusting the viscosity of a magnetic fluid, a bag body containing magnetic fluid is installed under the skin of each location where the hardness of the seat is adjusted, and The active control seat for a vehicle as described above, characterized in that a viscosity adjusting electromagnet is installed adjacent to the bag body.