JPS5848881Y2 - Low tire pressure indicator - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a tire air pressure drop display device for warning a driver or the like of a drop in tire air pressure in a vehicle.

Tire air pressure must always be maintained at an appropriate value not only to ensure the steering stability of the vehicle, but also to prevent tire wear and damage, and to prevent deterioration of fuel efficiency due to increased rolling resistance.

For this reason, for example, a tire pressure drop display device that is screwed onto the air pulp of a tire has been put into practical use, but this is because the pressing force of the spring becomes greater than the expansion force of the diaphragm due to the drop in internal pressure. The protrusion of the movable element is of a retractable type, and the size of the protrusion that normally protrudes is limited in terms of appearance quality, so it is extremely difficult to see and has the disadvantage of not being able to display clearly. A system using a pressure switch and a solenoid has been proposed as in 1982-179909, but the cost of the pressure switch is high, and compared to a system that uses only air pressure, it is difficult to handle rainwater in the electrical circuit. However, there are problems such as the need for a strict seal against mud and the need to replace the power supply battery.

This idea was made in view of the above points, and has a simple structure that uses the tire air pressure itself as the operating source.
It is an object of the present invention to provide a tire air pressure reducing device that can clearly display a display when the tire air pressure is reduced.

Hereinafter, one embodiment of this invention will be described in detail based on the drawings.

FIG. 1 shows a tire air pressure drop display device 1 according to this invention, and FIG. 2 shows a state in which this display device 1 is attached to a part of the center of a wheel 2.

In FIG. 1, 3 is a board that integrally has a wheel mounting bracket part 4, 5 is a cylindrical case fixed to this board 3 with screws 6, and 7 is a connector for introducing air pressure.
As shown in FIG. 2, the tip of a conduit 9 for taking out the air pressure of the tire 8 is connected to this connector 7.

Note that the connection between the conduit 9 and the tire 8 is made using the existing air valve 1.
0 may be used, or a separate pneumatic pressure outlet connector 11 may be provided.

12 is a transparent plate attached to the front surface of the case 5;
Reference numeral 3 denotes an opaque non-magnetic plate made of, for example, synthetic resin, which is disposed parallel to the back side of the transparent plate 12, and a relatively thin space 14 is formed between the two, in which an appropriate amount of liquid is applied. Magnetic powder 15 is enclosed.

Reference numeral 16 denotes a bellows, which is an example of a flexible member, and has one end fixed to the substrate 3 and the other free end facing the non-magnetic plate 13. It is biased and expands and contracts in accordance with the tire air pressure so that this biasing force and the tire air pressure inside the case 5 are balanced.

18 is an operating pressure adjusting screw for variably adjusting the biasing force of the operating pressure adjusting spring 17, and 19 is a nut portion into which this screw is screwed.

A plate-shaped magnet 20 is attached to the tip of the bellows 16, and as the bellows 16 expands and contracts, the non-magnetic plate 13
On the other hand, on the back side of the non-magnetic plate 13 on which the magnetic force acts, there is a magnetic plate cut out in the shape of a display character such as rAIRJ or a display figure such as rXJ to indicate the decrease in air pressure. 21 is fixed.

Note that each joint of the case 5 is sealed by filling a sealing agent or the like to maintain the airtightness inside the case 5.

Next, the operation of this tire pressure drop display device 10 will be explained.

The upper half of Figure 1 shows the normal tire air pressure.
The lower half shows the state at the time of decline.

That is, when the tire air pressure constantly introduced into the case 5 via the conduit 9 is sufficiently high, the bellows 16
is compressed, and the magnet 20 is in a position separated from the non-magnetic plate 13.

Therefore, no magnetic flux acts on the magnetic plate 21, and no display is performed.

On the other hand, when the tire air pressure decreases, the bellows 16 expands to the point where this and the biasing force of the operating pressure adjustment spring 17 are balanced, and the magnet 20 approaches the non-magnetic plate 13vc.

Therefore, the magnetic plate 21 on the back side of the non-magnetic plate 13 is attached to the magnet 2.
The magnetic powder 15 in the space 14 is attracted and collected on the non-magnetic plate 13 along the shape of the magnetic plate 21 .

This results in display characters such as rAIRJ. The figure is drawn on the non-magnetic plate 13.

Here, it is of course preferable that the magnetic powder 15 and the non-magnetic plate 13 on the background are colored in colors that are easy to distinguish, such as black and white.

To set the critical tire pressure that is displayed in this way, turn the operating pressure adjustment screw 18 and adjust the operating pressure adjustment spring 1.
It can be adjusted as appropriate by changing the urging force of 7.

Incidentally, it is also possible to omit the operating pressure adjustment spring 17 and the operating pressure adjustment screw 18, and as an alternative, fill gas in the bellows 16 and adjust the set air pressure by adjusting the amount of gas. .

(This applies to the embodiments shown in FIGS. 3, 5, 6, and 7, which will be described later.

) Also, without providing the magnetic plate 21 on the back surface of the non-magnetic plate 13, the third
As shown in the figure, a convex portion 20a in the shape of two display characters such as rAIRJ is formed on the surface of the magnet 200, and a non-magnetic plate 1
3, the magnetic powder 15 may be attracted and collected in a shape along this shape (O).Also, as shown in FIG. A bulge is formed on the magnet 2.
If a predetermined display is drawn on the dome-shaped non-magnetic plate 13 with a curved shape along this curve, this display can be seen from the side, and for example, the air pressure can be checked even when the driver is in the car. can be confirmed.

Furthermore, in each of the above embodiments, the magnetic force that passes through the non-magnetic plate 13 and acts on the magnetic powder 15 gradually changes depending on the tire air pressure, and this can be used to display multiple colors.

That is, it is sufficient to form a plurality of types of magnetic powder 15 with different adsorption properties by making the materials and particle sizes of the magnetic powder 15 different, and to color each one in a different color, in order according to the proximity of the magnet 20. Since the items that are easily absorbed gather together, the color of the display gradually changes depending on the tire air pressure.

Next, in the embodiment shown in FIG. 5, the suitability of the air pressure can be displayed more clearly in a binary manner.
The magnet 2 is connected to the inner wall, and when the bellows 16 expands, the magnet 2
0 exceeds the neutral point, it moves instantaneously to the dotted line position, and conversely, when it exceeds the neutral point, it instantaneously returns to the solid line position due to the contraction of the bellows 16, which is a so-called snap action.

Therefore, the presence or absence of the display by the magnetic powder 15vc is clearly indicated at the preset tire air pressure.

In this illustrated example, the magnetic powder 1 is spread along the entire surface of the magnet 20.
By attracting and gathering 5, the display is performed as a color change on the surface of the non-magnetic plate 13, but it is of course possible to display 2 characters and figures as in each of the embodiments described above.

Next, in the embodiment shown in FIG. 6, changes in tire air pressure can be continuously displayed, and a rod-shaped or band-shaped magnet 20 is used, and one end of the magnet 20 swings against the back surface of a non-magnetic plate 13. The bellows 16 is movably supported, and the tip of a bellows 16 is linked to the free end, and as the bellows 16 expands and contracts, the magnet 20 swings toward and away from the nonmagnetic plate 13 .

Therefore, the magnetic powder 15 is placed on the non-magnetic plate 13 and the magnet 2
They gather in a range of length t corresponding to the inclination of the magnet 20 from the part corresponding to the support end of the magnet 20 .

In other words, the collection length t of the magnetic powder 15 changes according to the tire air pressure, thereby making it possible to continuously display a decrease in the tire air pressure.

Incidentally, a scale for determining the above-mentioned length t or a color depending on the suitability of the air pressure may be provided on the non-magnetic plate 13.

The embodiment shown in FIG. 7 is a slight modification of the embodiment shown in FIG. The roller 41a at the tip is brought into contact with the back surface of the non-magnetic plate 13 by being biased by the coil spring 42, and the magnet 20 swings as the bellows 16 expands and contracts, similar to the embodiment shown in FIG. As described in detail above, according to the tire pressure drop display device of this invention, it is possible to continuously display the decrease in tire pressure by moving close to and away from the non-magnetic plate 13. On the other hand, when the tire air pressure is low, a clear display can be displayed on the transparent plate on the front of the case, allowing the driver and the like to clearly determine whether the tire air pressure is appropriate or not.

Furthermore, the moving parts are completely housed inside the case, so
There is no risk of contamination due to rainwater, mud, etc., and reliable display operation can be ensured over a long period of time.

Also, by displaying the shape of two letters indicating a decrease in air pressure.

It is possible to make visual recognition even easier, and it is also possible to display information according to the degree of air pressure drop.

In addition, although all of the above-mentioned embodiments have shown examples in which magnetic powder is collected when the air pressure decreases, on the other hand, when the air pressure decreases, the magnet moves away from the space in which the magnetic powder is enclosed. It is also possible to easily realize the above-mentioned explanation, and this is also the gist of the present invention.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of the tire air pressure drop display device according to this invention, Fig. 2 is an 11-view view of the entire tire (7) showing the mounting state of this display device, and Fig. 3 is a view showing the magnet surface. Sectional view showing an example in which display characters are formed in the shape of 2 figures, No. 4
The figure is a half-sectional view showing an embodiment in which the display surface is dome-shaped, FIG. 5 is a sectional view showing an embodiment in which the display surface has a snap action, and FIGS. It is a sectional view showing an example. 1... Tire pressure drop display device, 2...
...wheel, 3...board, 5...case, 8...tire, 9...conduit, 1
2...Induction plate, 13...Nonmagnetic plate, 14
......Space part, 15...Magnetic powder, 16.
... Bellows (flexible member), 17 ... Working pressure adjustment spring, 18 ... Working pressure adjustment screw, 20 ... Magnet, 21 ... ...magnetic plate, 3
1... Leaf spring.

Claims (4)

[Scope of utility model registration request] (1) A predetermined space is formed between a cylindrical case attached to the wheel, a transparent plate placed on the front side of the case, and a transparent plate placed on the back side of the transparent plate. a non-magnetic plate, a magnetic powder sealed in the space, and a non-magnetic plate arranged on the back side of the non-magnetic plate so as to be able to approach and separate from the non-magnetic plate, and the magnetic powder is attracted onto the non-magnetic plate by the approach. A tire air pressure drop display device comprising magnets that are assembled together and a flexible member that is displaced by tire air pressure to move the magnets. (2) Utility model registration claim 1, in which a magnetic plate in the shape of predetermined display characters and figures is fixed to the back surface of the non-magnetic plate, and is assembled so as to attract and collect the magnetic powder in a shape that follows the non-magnetic plate. The tire pressure drop display device described. (3) The tire air pressure according to claim 1, wherein the surface of the magnet is formed in a predetermined display character or graphic shape, and the magnetic powder is attracted and collected in a shape that follows this shape. Decline indicator. (4) A claim for utility model registration in which the magnet is arranged to approach and separate from the non-magnetic plate by swinging, and is configured to attract and collect the magnetic powder from one adjacent end according to its inclination. The tire air pressure drop display device according to scope 1.