JPH0326426Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a liquid level detection device for detecting the level of a liquid and issuing a predetermined warning, and in particular, the present invention relates to a liquid level detection device for detecting the level of a liquid and issuing a predetermined warning. The present invention relates to a structure that prevents malfunction caused by the liquid, and is effective for use in, for example, a liquid level detection device used in a fuel tank of a two-wheeled vehicle such as a motorcycle.

[Conventional technology]

Conventionally, a liquid level detection device used in a motorcycle fuel tank includes a switch case housing a reed switch, a float fitted to the case so as to move up and down in accordance with the liquid level. The reed switch is equipped with a magnet that is attached to the float to open and close the reed switch, and when the float drops to a predetermined position due to a drop in the liquid level, the reed switch responds to the magnet and activates a warning light, etc. Some devices are configured to do this.

In such a liquid level detection device, the float easily follows irregular vertical movements of the liquid level, so even if there is sufficient fuel in the tank, when the motorcycle suddenly starts or stops, There is a risk of false alarms occurring when the liquid level suddenly moves up and down.

Therefore, a liquid level detection device has been proposed in which the float is surrounded by a cover to prevent irregular vertical movements of the liquid level from being immediately transmitted to the float, thereby preventing false alarms.

Conventionally, this type of liquid level detection device has a switch case that is integrally molded with the tank, and a small hole formed on the bottom of the cover is fitted into a protrusion formed on the lower end of the case. There is one in which a cover is fixedly attached to the top (for example, see Japanese Utility Model Application No. 56-86519).

[Problem that the invention attempts to solve]

However, in such a liquid level detection device,
Since the cover is configured to be caulked with a protrusion formed at the lower end of the switch case, there is a problem in that the cover cannot be attached later to a general existing liquid level detection device.

An object of the present invention is to provide a liquid level detection device in which a cover can be attached to the outside of the float as desired to prevent the float from overly following irregular fluctuations in the liquid level. be.

[Means for solving problems]

The liquid level detection device according to the present invention is disposed at the lower end of a housing 1, and includes a switch case 4 in which a reed switch 5 is housed, and a switch case that moves up and down in accordance with the liquid level. 4, a magnet 18 that is attached to the float 17 to open and close the reed switch 5, and a cover 1 that is attached to the switch case 4 so as to surround the float 17.
9, a holding plate 11 having elasticity is fixed to the upper part of the switch case 4, and a stopper 10 is fixed to the lower part of the switch case 4, An engaging convex portion 24 is provided on the inner periphery of the cover 19 to protrude radially inward, and this engaging convex portion 24 engages the holding plate 11 and the stopper 10.
The retaining plate 11 is held between the retaining plate 11 by the elastic force thereof, and the retaining plate 11 has a cutout portion that allows the cover 19 to move by inserting the engagement convex portion 24 of the cover 19 into the retaining plate 11. It is characterized by the fact that 14 have been established.

[Effect]

When the liquid level suddenly moves up and down, the cover prevents the up and down movement from being immediately transmitted to the float, thereby preventing the float from following the up and down movement and dropping suddenly. Therefore, false alarm activation of the reed switch 5 due to the float excessively following the liquid level is prevented.

Since the cover is attached to the outside of the float by being sandwiched between a plate fixed to the switch case and a stopper, it can be easily assembled to an existing product later.

〔Example〕

Fig. 1 is a partially cutaway front view showing a liquid level detection device which is an embodiment of the present invention, Figs. 2 and 3 are front and bottom views showing a holding plate, and Fig. 4 shows a state in the middle of assembly. FIG.

In this embodiment, the liquid level detection device includes a housing 1, and the housing 1 is integrally molded of resin or the like into a substantially cylindrical shape with an open upper end and a closed lower end. A rubber cap 2 is attached to the upper opening of the housing 1.
The liquid level detection device is attached to a fuel tank of a two-wheeled vehicle and is formed to maintain a seal. The housing 1 houses an electrical component 3 for detecting the liquid level and checking the alarm operation, as well as for protection. )
It is designed to be electrically connected to via wiring 3a.

A switch case 4, which is made of resin or the like and is formed into a small diameter, substantially cylindrical shape, is fixed to the lower end of the housing 1 so as to project so as to substantially coincide with the center line. A reed switch 5 that opens and closes in response to magnetic force is disposed approximately on the center line inside the switch case 4, and this switch 5 is electrically connected to the electric component 3. An excitation coil 6 is arranged on the inner periphery of the switch case 4 so as to surround the reed switch 5.

A pair of male engaging portions 7 are provided at the upper end of the switch case 4 and protrude in opposite directions in the radial direction.
When this engaging part 7 is engaged with the female engaging part 8 formed on the lower end opening/closing wall of the housing 1,
The switch case 4 is fixed to the housing 1. An annular groove 9 is provided on the outer periphery of the lower end of the switch case 4.
This groove 9 is configured such that a C-ring 10 serving as a stopper is inserted and fixed therein.

A holding plate 11 as shown in FIGS. 2 and 3 is fitted onto the upper end of the switch case 4 and is fixed using the male engaging portion 7. That is, the holding plate 11 is integrally formed into a substantially disk shape using a thin plate having appropriate elasticity such as a spring plate material by an appropriate means such as press working. Holding plate 11
An insertion hole 12 is formed approximately in the center of the switch case 4 so that the switch case 4 can be inserted therethrough, and a pair of female engaging portions 13 are arranged in opposite directions in the radial direction on the edges of the insertion hole 12. It is formed so that it can be tightened in a state in which the male engaging portion 7 is inserted.

Then, the holding plate 11 is fitted to the upper end of the switch case 4 by relatively inserting the switch case 4 into the insertion hole 12, and further, the male engaging part 7 is fitted into the female engaging part 13. This makes it relatively fixed to the switch case 4.

A plurality of notches 14 are cut out on the outer periphery of the holding plate 11 at approximately equal intervals in the circumferential direction, and the notches 14 are formed so that ribs of a cover, which will be described later, can be inserted therethrough. . A position regulating pawl 15 is protruded from a portion adjacent to one side of each notch 14 in the circumferential direction by bending a portion of the holding plate 11 at a substantially right angle in a direction away from the end surface of the housing 1 . An inclined surface portion 16 is formed by cutting and raising a part of the holding plate 11 at a portion adjacent to the other side of each notch portion 14, and the inclined surface portion 16 becomes closer to the housing as it moves away from the notch portion 14 in the circumferential direction. It is inclined so as to gradually move away from the end face of 1.

A float 17 made of a material with low specific gravity such as polyurethane and formed into a thick-walled substantially cylindrical shape is fitted onto the outer periphery of the intermediate portion of the switch case 4 so as to be movable in a direction parallel to the center line. A ring-shaped magnet 18 is fitted onto the inner periphery of the float 17.

A cover 19 is provided on the outer side of the float 17 so as to surround the float 17, and the cover 19 covers the holding plate 11 and the annular groove 9.
It is fixed to the switch case 4 by a C ring 10 fitted to the switch case 4.

That is, the cover 19 is integrally molded using translucent resin into a substantially cylindrical shape with an open upper end and a closed end, and the closed wall and the open end of the cylindrical wall are designed to allow fuel to flow in and out. flow path 20,
A plurality of 21 are formed. A substantially cylindrical recess 22 is arranged concentrically in the center of the closing wall of the cover 19 and recessed in the direction of the opening surface. It is perforated so that it can be inserted through it. On the inner periphery of the cover 19, the same number of ribs 24 as engagement protrusions as the notches 14 of the holding plate 11 are arranged at approximately equal intervals in the circumferential direction, and are approximately aligned with the center line from the vicinity of the opening to the closing wall. They are provided to protrude in the radial direction so as to extend in parallel.

When the cover 19 is assembled to the switch case 4, the switch case 4 is relatively inserted into the cover 19 from the opening, and its tip is inserted into the insertion hole 23 of the cover 19. At this time, the fourth
As shown in the figure, the holding plate 11 is fitted into the opening of the cover 19, and the rib 24 of the cover 19 is inserted into the notch 14 of the holding plate 11.
is inserted relative to the This rib 24
By inserting the switch case 4 into the notch 14,
The leading end of the cover 19 is projected from the insertion hole 23 of the cover 19. Therefore, it becomes extremely easy to fit the C-ring 10 into the annular groove 9 protruding from the cover 19.

After the C-ring 10 is fitted, the cover 19 is moved in the opposite direction to the housing 1, so that the rib 24 is pulled out from the notch 14. continue,
The ribs 24 circumferentially move the cover 19 into position regulating claws 15.
When the cover 19 is rotated until it comes into contact with the C-ring, the rib 24 slides on the inclined surface 16, and the cover 19 is pushed away from the housing 1. 10. In this state, the rib 24 is pushed by the holding plate 11 and the reaction force is received by the C-ring 10 in the recess 22, so that the cover 19 is moved between the holding plate 11 and the C-ring 10 with the switch case 4 as a pivot. be held between.

If the cover 19 is semitransparent or transparent, the inside of the cover can be seen through, making the above-mentioned work easier.

Next, the action will be explained.

The liquid level detection device according to the above configuration is installed in a fuel tank of a two-wheeled vehicle. When the fuel in the tank is above the set level, the float 17 floats up due to buoyancy, so the magnet 18 separates from the reed switch 5, and the reed switch 5 maintains the non-warning state.

By the way, when the fuel tank of a two-wheeled vehicle is formed into a hollow body having a substantially triangular prism shape, the liquid level tends to move up and down rapidly and greatly when the vehicle suddenly starts or stops suddenly. When the liquid level moves up and down significantly like this,
If the float moves up and down to follow this movement, the reed switch will actuate a warning in response to the movement, so there is a risk that a warning will be issued erroneously even though sufficient fuel has been stored.

However, in this embodiment, since the cover surrounds the float, such a false alarm phenomenon can be avoided.

Normally, the fuel in the tank flows inside and outside the cover 19 through the flow passages 20 and 21, so the float 17 floats up inside the cover 19, thereby causing the reed switch 5 to maintain the non-warning state.

Even if the liquid level outside the cover 19 suddenly drops when the liquid level suddenly moves up and down, such as during a sudden start or sudden stop, the fuel inside the cover 19 will flow through each flow path 20,
Since fuel 21 alone cannot be discharged instantaneously, fuel remains inside the cover 19. Since the float 17 is maintained in a floating state by this residual fuel, the non-warning state of the reed switch 5 is maintained.

Then, when the fuel decreases and the liquid level falls below a set level, the fuel in the cover 19 is gradually discharged from each flow path 20, 21. Due to this discharge, the float 17 descends, so the magnet 18 approaches the reed switch 5, and the reed switch 5 responds to this and activates a warning.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and may be modified without departing from the gist thereof.
It goes without saying that various changes are possible.

For example, the engaging convex portion of the cover that presses against the holding plate and C-ring is not limited to the rib and the opening edge of the switch case insertion hole, but may also be a protrusion or pin protruding from the opening and closing portion of the cover. Good too.

The stopper that presses against a part of the cover is not limited to a C-ring, but may be a stopper pin, split pin, nut, or the like.

[Effect of idea]

(1) By attaching the cover to the switch case so as to surround the float, when the liquid level suddenly moves up and down, the up and down movement can be prevented from being transmitted to the float immediately by shielding the cover. Therefore, it is possible to avoid the float from following the liquid level excessively, and it is possible to prevent false alarms from occurring due to this.

(2) Since the cover is held between a holding plate with elastic force and a stopper using the switch case as a pivot, the elastic force of the holding plate simplifies the assembly work, and the cover can be firmly fixed.

(3) Since there is no need to modify the switch case etc., the cover can be attached to existing products, and the switch case 4 can be easily adapted to diversification.

(4) By providing a notch in the holding plate through which the rib of the cover can be inserted, the annular groove of the switch case can be made to protrude from the cover by inserting the rib into the notch when assembling the cover. , the work of attaching the stopper to the switch case can be simplified.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view showing a liquid level detection device which is an embodiment of the present invention, Figs. 2 and 3 are front and bottom views showing a holding plate, and Fig. 4 shows a state in the middle of assembly. FIG. 1...Housing, 2...Rubber cap, 3...
...Electrical component, 4... Switch case, 5... Reed switch, 6... Excitation coil, 7... Male engaging part, 8... Female engaging part, 9... Annular groove, 10... C
Ring (stopper), 11... Holding plate, 1
2...Insertion hole, 13...Female engaging part, 14...Notch part, 15...Position regulating claw, 16...Slope part, 1
7...Float, 18...Magnet, 19...
Cover, 20, 21...flow path, 22...recess,
23...Insertion hole, 24...Rib (engaging protrusion).

Claims (1)

[Scope of Claim for Utility Model Registration] A switch case 4 which is disposed at the lower end of the housing 1 and has a reed switch 5 housed therein, and a switch case 4 which moves up and down in response to the liquid level. Float 17 being extrapolated,
The reed switch 5 is attached to the float 17.
a magnet 18 that opens and closes the float 17;
A cover 19 is fitted over the switch case 4 so as to surround the switch case 4, and an elastic holding plate 11 is fixed to the upper part of the switch case 4. A stopper 10 is fixed to the lower part of the switch case 4, and an engaging convex portion 24 is provided on the inner circumference of the cover 19 to protrude radially inward, and this engaging convex portion 24 serves as the retainer. Plate 11 and the stopper 10
The retaining plate 11 is held between the retaining plate 11 by the elastic force thereof, and the retaining plate 11 has a cutout portion that allows the cover 19 to move by inserting the engagement convex portion 24 of the cover 19 into the retaining plate 11. A liquid level detection device characterized in that 14 is provided.