DE8004896U1 - A LEVEL DETECTOR INTEGRATED IN A PLASTIC BRAKE FLUID TANK FOR MOTOR VEHICLES - Google Patents

Description

A level warning sensor integrated in a plastic-made brake fluid holder for motor vehicles

The invention relates to a level warning transmitter with the features of the preamble of claim 1.

ff Such level warning devices are known. For checking

the level warning function (contact transfer of the filling level is arranged in the warning device warning electrical contacts, function \ l of the warning signal generator or the like.) is attached to such a liquid level

ji warning devices a test cap is provided with which the con-

Cycle of the warning contacts is closed manually and the function of the warning signal generator located in the vehicle is checked can be. If the warning indicator responds to such a check, the vehicle driver also has the Driving operation the certainty that if the brake fluid level drops below a required minimum the warning signal generator also indicates this deficiency in the braking system,

In the prior art, such test caps are inherently rigid. They are on a hollow cylindrical projection

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of the brake fluid reservoir mounted in a height-adjustable manner and can be pressed down manually against spring force in the direction of immersion of the float body in the brake fluid will. When the test cap is pressed down, the float body is acted upon by the test cap from above, immersed in the brake fluid against its buoyancy and thereby the contact path of the warning switch by means of a contact element arranged on the float body closed.

Such known level warning devices have the disadvantage that, due to their relatively complex mechanical Structure are prone to failure and their assembly is associated with a considerable amount of time. For sealing opposite the container are such test caps with sealing elements, such as O-rings or the like. Mistake. These sealing elements can easily have leaks and must be replaced, especially after prolonged use will,

The object of the invention is to functionally improve level warning devices of the type mentioned at the beginning and simplify. This task is carried out by the indicator of claim 1 solved.

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The solution is initially to assemble such devices simplified, since additional spring elements or sealing parts can be completely omitted. Further The one-piece design of the pressure cap with the container prevents leaks in the sealing cap area. The increased tightness due to the invention has an advantageous effect especially when prior to filling the brake fluid largely affects the entire brake system should be evacuated.

The characterizing features of the subclaims relate in particular to advantageous designs of the subject matter of the invention. For example, the upwardly curved, frustoconical cross-section of the sealing cap that, despite sufficient mechanical rigidity, it springs back into its rest position after actuation. Furthermore, the upwardly curved cross-section ensures that the sealing cap can be operated conveniently.

The arrangement of two concentric, ring-shaped film hinges in the upper part of the sealing cap means that the required Adjustability of the sealing cap created, with a sufficiently rigid design of the center of the Dicfit cap for transferring the actuation pressure on the float body is guaranteed.

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Due to the features of claim 4, the actuation is the Sealing cap with now low actuation force made possible.

By arranging a pressure transmission stop surface at the bottom of the center of the sealing cap is on the one hand a good transmission of the actuation pressure is guaranteed. Through the protruding into the interior of the container Sealing cap side wall, a guide for the float body is created in an advantageous manner. Additional guide parts can thus be omitted.

The invention is explained in more detail using an example shown in the drawings. Show it: 1 shows a cross section through the level warning transmitter and FIG. 2 shows a detailed cross section through the sealing cap.

With 1 in Fig. 1, a brake fluid reservoir is designated- } i

net, the level indicator 2 f according to the invention

Is provided. The level warning sensor 2 consists in the we- |.

sentlichen from a float body 3, which at its upper ^

side a float body neck 4 carries. Above the float- ■

body 3 is integral to the housing 1 a sealing cap 5 i '

integrally formed, the upper part of which consists of a pressure transmission disk; be 6 and a cone jacket ring area 7 consists. The upper

side protrudes beyond a cylindrical sealing cap side wall 8. Between the pressure transmission disk 6 and the conical casing ring area 7 there is a first film hinge in the shape of a ring 9 and between the conical casing ring area 7 and the sealing cap side wall 8, a second annular film hinge 10 introduced. The first film hinge 9 and the second film hinge 10 are concentrically one inside the other in the Upper part of the sealing cap 5 is arranged.

The sealing cap 5 covers two contact pins 11 and a on the float body neck 4 attached contact element 12. The contact pins 11 are substantially parallel and are so held in the sealing cap side wall 8 that their connection ends outside of the sealing cap side wall 8 to Connection of electrical cables are exposed.

The sealing cap side wall 8 sits down below the upper wall 13 of the brake fluid container 1 and projects downwards continues and there forms a hollow cylindrical float body housing 14. The radially outer circumference 15 of the float body 3 is vertically displaceable in the float body housing 14 forcibly guided.

On the underside of the pressure transmission disk 6 is a Pressure transmission stop surface 15 arranged, the central

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is above the upper end 16 of the float body neck 4.

When there is sufficient brake fluid in container 1, the float body 3 is displaced upwards by the brake fluid; the upper end 16 of the swimmer neck 4 lies at the same time on the pressure transmission stop surface 15, the contact element 12 being lifted off the contact pins 11 is. If the fluid level in the brake fluid container 1 falls, then when the fluid level falls below a minimum the float body 3 also lowered so far that the contact element 12, the two contact pins 11 conductively connects. This connection of the contact pins 11 closes a circuit and the circuit in these Circuit activated warning signal generator triggered.

To check the functionality of the contact pins 11 and contact element 12 formed warning switch and the downstream electrical warning system is filled with Brake fluid reservoir 1 thereby manually closes the contact path between the contact pins 11, that the sealing cap 5 arranged over the contact elements is pressed downwards.

In Fig. 2 is a cross section through the sealing cap 5 in Detail shown. If the pressure transmission disc 6

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manually pressed down, so the cone jacket ring area 7 pivoted downwards with simultaneous compression of the film hinges 9 and 10 9 and 10 causes the sealing cap to resiliently spring back into it after the actuation process has ended Rest position. A bending of the conical jacket ring area 7 and the pressure transmission disk 6 when the Sealing cap 5 does not take place.

Claims (6)

ι ■ · ι II · 1 I Il I I I I Walter Alfmeier GmbH + Co, 8830 Treuchtlingen Protection claims: 1.) In a brake fluid reservoir made of plastic for motor vehicles integrated level warning device with 1. a vertically movable float body, 2. an electrical warning switch operated by the float, 2.1 whose contact path is opened when a minimum liquid level in the container is exceeded and 2.2 is closed when the liquid level falls below a minimum and a warning signal transmitter turns on, as well 3. with a test cap that can be manually operated vertically downwards, which 3.1 is arranged above the float body and 3.2 acts on the float body from above in the actuating position, characterized in that tr./:, 4. the test cap as elastic in the immersion direction (17) of the float body (3) deformable pressure actuation sealing cap (5) is integrally formed on the brake fluid reservoir (1). 2.) level warning device according to claim 1, characterized, that the pressure actuation sealing cap (5) has an upwardly curved, essentially frustoconical cross section having. 3.) Füllstandswarngebsr according to claim 1 or 2, characterized through the following features: 1. The upper part of the sealing cap is supported by a central pressure transmission disk (6) and a pressure transmission disk (6) formed radially outwardly surrounding the cone jacket ring area (7). 1.1 The pressure transmission disk (6) and the conical casing ring area (7) are formed by a ring-like wall area reduced wall thickness - called "first film hinge" (9) for short - connected to one another. 1.2 The radially outer edge of the conical casing ring area (7) is reduced in wall thickness by means of an annular wall area - in short "second" Film hinge "(10) called - with a cylindrical Sealing cap side wall (8) connected. 4.) Level warning device according to at least one of the preceding Claims, characterized by the following geometric relationships in the rest position: 1. The pressure transmission disc (6) and the cone jacket ring area (7) form a smaller angle than in the actuated position. 2. The cone jacket ring area (7) closes with the Sealing cap side part (8) forms a larger angle than in the actuated position. 5.) Level warning device according to at least one of the preceding claims, characterized in that
1. On the underside of the pressure transmission disc (6) is a pressure transmission stop surface (15) molded which 1.1 aligned perpendicular to the immersion direction (17) is. 6.) Level warning device according to at least one of the preceding Claims, characterized by the following features: 1. The sealing cap side wall (8) protrudes in a cylindrical shape as a float housing (14) down into the container (1). 2. The radially outer circumference of the float body (3) can be moved higher in the float housing forced.