DE1941646A1 - Device for displaying a predetermined wear value of friction linings - Google Patents

Description

Patent application 12. » August 19 & 9

ADAM OPEL AKTIENGESELLSCHAFT

werJ; es_v ^ n_Rj3ibbelägen ..

The invention relates to a device for displaying a predetermined wear value of friction linings with a distance between that caused by the friction lining when the wear value falls below this value Part to be braked and an electrical contactor which can be brought into the closed position relative to this movable part in an electrical circuit in which the for example designed as a lamp, buzzer or the like Display device is arranged, and relates in particular to such a device for displaying a predetermined Wear value of friction linings on disc brakes.

In the case of brake linings, especially those of disc brakes, there is a risk that the covering will wear out completely between the inspection intervals and with it metallic back plate in contact with the brake

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disk comes, leading to brake failure with its particular can lead to significant consequences if the disc brake is installed in a motor vehicle. Devices have therefore been developed that use optical and acoustic displays to alert the driver to critical pad wear to draw attention. .

For this purpose, in known constructions, electrical contacts have been embedded in the covering material, which come into contact with the brake disc when the covering material above them is worn and thereby actuate a warning display. In another known embodiment, contacts were attached to the lining carrier plates, which protrude in the direction of the brake disc by an invariably predetermined amount and when the lining material in excess of this amount wears in w Step into contact, thereby creating an electrically conductive con

Establish cycle to the brake disc and also activate the warning display.

Apart from the fact that these known devices in the Manufacturing are expensive, they only know each other be used to wear the brake pads When making contact with the friction lining, which is relative to the

and this is operated in this state for a long time.

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Friction lining carrier and the contact moving part with this Contact, with the known devices, the contact is constantly worn known devices for further use after replacement dejB worn friction lining against another unusable. Special brake pads with pressed-in contacts require separate storage of pads when installing is only provided as an option.

The invention has set itself the task of addressing the disadvantages to avoid the known devices and a device for displaying a predetermined wear value of Friction linings, in particular of friction linings of disc brakes, with a wear value when falling below this one corresponding distance between the part to be braked by the friction lining and a part relative to this movable part brought into the closed position electrical contactor in an electrical circuit in which the For example, designed as a lamp, buzzer or the like display device is arranged to create the even if the friction lining is worn down to the predetermined critical value and exchanged for one fresh friction lining while at the same time simplifying and making the corresponding replacement work cheaper.

This object is achieved by the invention in that the contactor Supported by the brake housing and by an anti-movement rotatably held parallel to the friction surface of the friction lining, transversely to the friction surface of the friction lining movable part can be actuated as soon as the distance from this part closes the part to be braked by the friction lining falls below a predetermined value.

The invention thus goes a completely different way than the known devices. Namely, it arranges the contactor beyond the range of motion of the relative

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tiv to the brake housing moving part, for example the Brake disc, stationary and makes it dependent on the application of pressure by a likewise movement in the direction of the friction lining between and to be braked by this Part acting frictional forces are not going through part, which rather only transversely to the direction of this friction forces depending on the wear value of the friction lining is movable. This achieves according to the invention that the contactor is not subject to any signs of wear and tear and is therefore practically unlimited Has lifetime.

It has been found that, particularly in the case of known disc brakes with a fixed caliper with an expanding spring this results in a particularly simple and cheap construction according to the invention that the contactor of, which is supported against the brake housing Spreading spring worn for the brake lining carrier (s) is. -

According to a further non-obvious embodiment of the invention, the contactor can advantageously be two in one elastic insulation jacket, preferably made of synthetic material have arranged contact tongues, which under transversely to the friction surface of the friction belt or the friction linings attacking pressure can be brought into electrically conductive contact with one another. In this way becomes the possibility for further simplification and cheaper the invention created by namely not only the contactor is designed so that it is after modern manufacturing methods produced cost-saving can be, but that also its assembly and in particular its assignment to the one or those acting on it Part (s) and the corresponding adjustment considerably simplified and the need for Ieolirungen on others, having a considerably more complicated shape Having to provide for sharing is turned off.

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In a further advantageous embodiment of the invention, one of the Contact tongues have an electrically conductive connection with electrical ground via a carrier part of the friction lining carrier. This The carrier part can advantageously be one of the lining retaining pins. This reduces the wiring effort for the electrical connection of the contactor to the circuit of the warning display is kept low and simplifies the electrical connection assembly. In some applications, especially when there is no electrical ground is available in a conductive connection, which can be the case, for example, when the relevant components consist of electrically non-conductive material, but it can also be useful to use both contact tongues by means of electrical cables to be connected to the electrical circuit.

A particularly simple construction with the possibility of simpler and convenient assembly results according to the invention in that the Contactor is unbuttoned on the longitudinal bracket of the expanding spring.

The contactor is expediently fixed in relation to a carrier part of the friction lining carrier. Ale Such a support member for fixing the contactor can be one of the pad retaining pins are used. "..--.

In order to avoid that the contactor when pressing the Contact tongues is pressed at an angle, he can according to an expedient development of the invention about in the area of his Contact tongues facing away from the free end to its central longitudinal line have approximately symmetrical widenings.

A preferred embodiment of the invention is characterized in that when the predetermined wear value of a friction lining is reached, the contactor can be brought into an electrically conductive switching position by the friction lining carrier associated with this friction lining. An expedient further development is characterized in that the contactor is arranged in such a way that when the predetermined wear value of a friction lining is reached

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this associated Kontaktzungeη the Kontaktgeberß through the ειη it coming to the plant associated with this friction lining ßeibbelagtrfiger in electrically conductive contact with the other contact tongue can be brought.

A device for optional setting is useful of the desired distance value corresponding to the predetermined wear value is provided. It can be advantageous the friction lining carrier (s) on his or her side coming into contact with the contactor each one transversely have adjustable pressure surface to the friction surface of the friction lining. One both in terms of manufacture and in terms of subsequent adjustment simple preferred embodiment results from the fact that the adjustable pressure surface through the tip of one in a transverse to the friction surface of the friction lining extending threaded hole is formed in the friction lining arranged screw.

Further simplifications as regards manufacture and assembly arise according to a further advantageous embodiment of the invention in that the contactor is W-known plug connections is connected to its electrical (s) feed line (s) to the electrical circuit by means of. ■ "."". -

Although the invention is based on a preferred embodiment with an electrical contactor as a pulse generator for the indication of reaching a predetermined one, for example the critical wear value is shown,

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via impulse transmission lines designed as electrical cables which feeds the pulse (s) to the again electrically operated display device it can be seen that other impulse transmission media in the Can come within the scope of the invention for use, such as hydraulic or pneumatic energy transmission media. Such a design can be advantageous, for example, in a brake system in which the im During the braking process, larger vibrations occur, which generate and transmit electrical impulses appear inexpedient, or at the use electrical energy is not permitted for any reason, as is the case with large Special test stands which Pail can be. In such a If other energy carriers are used than electrical ones Energy is more responsive to the pressure than the energy used Pulse emitting pulse generator trained Contactor and a correspondingly responsive to these impulses Display device for use via suitable impulse transmission lines, for example Pressure medium lines, is connected to the assigned pulse generator.

In the following, the invention is described in more detail purely by way of example using two preferred exemplary embodiments. Show:

FIG. 1 shows a schematic representation of a vertical section through an exemplary embodiment of the invention in FIG Application in a disc brake for motor vehicles with double-sided acting on the brake disc Brake pads along line I-I according to Figure 2;

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FIG. 2 shows a plan view of the device according to FIG. 1 with the upper part of the contactor cut off;

FIG. 3 ″ a side view of the device according to FIG and FIG. 2 from direction A with an approximately vertically logged contactor in an operating state, at which either has not yet worn the brake pads or has not yet reached the critical value Wear and tear is present;

FIG. 4 shows a part of the illustration according to FIG Operating condition in which both brake or friction linings have a predetermined critical value exhibit corresponding wear;

FIG. 5 shows, in the illustration corresponding to FIG. 4, an operating state in which only one of the friction linings has reached its critical wear value;

Figure 6 in the illustration according to Figure 1 corresponding Representation 'a further preferred embodiment of the invention, in which this in Vertical section along line VI-VI according to FIG. 7 is shown;

Figure 7 in the illustration according to Figure 2 corresponding Representation of a plan view of the exemplary embodiment according to FIG. 6 with the upper part of the contact bar again cut off;

FIG. 8 shows a view of the exemplary embodiment according to FIG 6 and 7 from direction A in an operating state in which the wear of the friction linings is still below the predetermined critical value; and

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Figure 9 in the representation according Pigur 8 corresponding representation, the operating state of this-embodiment, the same reached in which both friction linings to their degree of wear, wherein the ^e enters the inventive device in effect.

Corresponding parts are given the same reference numerals marked.

With 4 the brake disc is designated, on both sides of which a brake lining 15a or 15b engages when the disc brake is actuated, which is carried by a brake lining carrier 1 or 2, which by means of a suitably known, / iron designed actuator, for example a hydraulically actuated piston 5, transversely to the direction of movement of the brake disc 4 can be moved towards the latter. Midway between the walls 14 of the brake housing is a bracing spring centered 12 by the levers 6, which "rest of the brake housing on the walls 14 and are supported on this. The expanding spring 12 is in the manner of a conventional disc brake fixed saddle against the pad retaining pins 3 and the \

Friction lining carriers 1, 2 supported and in their position held.

In the embodiment according to. Figure 1 is on the expanding spring 12 a contactor 10 / unbuttoned, the two in one Plastic sheath 10 'enclosed electrical contact tongues 7, 0, of which one contact tongue B via the cable 11 to the electrical, not shown Circuit is connected to the display device leads, while the other contact tongue 7 from the Isolationeummantelung 10 * leads out in such a way that it goes through the

middle lateral lobe 30 and J1

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Spreading spring 12 with a contact surface provided for this purpose in electrically conductive contact with the one Pad retaining pin 3 is pressed and thus the electrical Establishes a lead connection to the ground. The contact tongue 8 is electrically conductively connected to the cable 11 by means of the plug connection 9.

The contactor 10 is designed and arranged so that when the predetermined wear value fe of a friction lining 15a or 15b is reached, it is brought into an electrically conductive switching position by the friction lining carrier 1 or 2 assigned to this friction lining, the contact tongue 7 assigned to this friction lining or 8 of the contactor is brought into electrically conductive contact with the other contact tongue or 7 by the friction lining carrier 1 or 2, which comes to rest on it and assigned to this friction lining. The width of the contactor 10 is so dimensioned that it is wider than the brake disc 4 by the dimensions 1γ and L _2.

When the lining is worn, the pistons 5 push the friction lining carriers 1 and 2 with the friction linings W 15a and 15b they carry against the brake disc 4 until the friction lining carriers 1, 2 press the contacts 7 and 8 together _{with the remaining lining thickness R ^ and R 2 and activate the display device} . This operating state is shown in FIG.

Even with one-sided lining wear or eccentric Assembly of the brake caliper is guaranteed to function. For example, friction lining 15b can be earlier up to the predetermined one critical value of its remaining lining thickness, be worn as a friction lining 15a, so that its friction lining 2 rests on the contactor 10 earlier than the friction lining carrier 1. About the cross bracket 6, the expansion spring 12 is to

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Braking housing Ik supported and forms the necessary reaction force to compress the contacts 7 and 8. So that the contactor 10 is not pushed crookedly when it is only attached to the expanding spring 12 by means of the tabs 30, extensions 13 are provided, which at the point of Tabs 31 of the contactor 10 are provided or formed by them.

In the exemplary embodiment according to FIGS. 1 to 5, according to the invention, a device for the optional setting of the desired distance R or R corresponding to the predetermined wear value is provided, which is designed in the most simple manner as a screw 21a or 21b, which is located in an unspecified threaded hole is adjustable in the friction lining 1 or 2 in the direction of the contactor 10. By appropriately turning the screw 21a or 21b, it can be determined when the adjustable pressure surface 21a ¹ or 21b ¹ formed by the tip of this screw 21a or 21b comes into pressure contact with the contactor 10. In Figure 2 and 3, the screws 21a, 21b are shown so that they protrude beyond the respective associated friction lining 1 and 2, while they are shown in Figures A and 5 so that their tip within the threaded hole in the respectively associated Friction lining carriers 1 and 2 are located and therefore this friction lining in each case comes directly into the action of pressure on the contactor. If the predetermined wear value at which the display device is to be made to respond is selected to be greater, then only the screw 21a or 21b needs to be turned so that its tip is removed from the respectively assigned friction lining 1 or 2 by a correspondingly larger amount protrudes.

The exemplary embodiment according to FIG. 6 and 9 differ from the execution example according to Figure 1 to 5 essentially only through the different design of the

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Contactor 20. Although this is in the same way, as already described in connection with the exemplary embodiment according to FIGS. 1 to 5 with regard to the contactor 10, fixed to the expanding spring 12. Are in it however, its two contact tongues 17, 18 again surround from an insulation jacket 20 'made of plastic material, so arranged and designed that both have each cable connection 21 or 22 to the electrical circuit, not shown, which connects the contact clock generator 20 to the display device connects, are connected. Accordingly. Is'

tk also no electrically conductive connection between a contact and a carrier part of the friction lining carrier 1 or 2, such as the lining retaining pin 3 »is provided. The cable connections 21, 22 are via a suitable plug-in. connection 19 with the contact tongues 17 and 18 of the contactor 20 electrically connected. Furthermore, in the exemplary embodiment according to FIGS. 6 to 9, no device is provided for arbitrarily changing the predetermined wear value at which the display device is made to respond. Rather, this wear value is determined here by the value by which the contactor width is greater than the width of the brake disk 4. Since (which is otherwise not shown in FIGS. 8 and 9) the

W contactor 20 is supported fixedly to the housing in the same way as the contactor 10 of the exemplary embodiment according to FIGS. 1 to 5, the mode of operation of this exemplary embodiment is otherwise the same as in the exemplary embodiment according to FIG Function of the device according to the invention is also guaranteed if one-sided lining wear occurs or the brake caliper is mounted off-center for any reason.

Although the invention is only described in more detail purely for example on the basis of two preferred exemplary embodiments. *in

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has been practiced, it is - as has already been explained by the way - not limited to this. Rather, it suits that A wide range of options open to experts, adaptations to given structural or operational conditions and certain requirements of the individual application through modification or different combinations of described features of the invention or to replace them with other measures having the same effect without thereby leaving the scope of the invention.

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Claims (1)

) / Device for displaying a predetermined wear value ~ of friction linings, in particular friction linings of disc brakes, with a distance between the part to be braked by the friction lining and an electrical control device in an electrical circuit that can be brought into the closed position relative to this part that is movable in relation to this wear value is one in which the W, for example, reasonable as a lamp, buzzer or the like formed display means arranged, characterized in that the contactor (10 or 20) brake housing fixedly supported, and by a counter movement to the friction surface (15a 'resp .. 15b ¹⁾ parallel of the friction lining (15a or 15b) held non-rotatably and transversely to the "friction surface (15a ¹ or 15b ¹ ) of the friction lining (15a or 15'b) movable part (1 or 2) can be actuated as soon as the distance (R ₁ or Rg) from this part (1 or 2) to the part (4) to be braked by the friction lining (15a or 15b) below a predetermined value itet. -, 2.) Device according to claim 1, characterized ... characterized in that the contactor (10 or 20) of one. B _f I against the brake housing (14) supporting expansion spring (6) for 1098 1 1/0767 - -. ■■ -2 » the or «the brake lining carrier (1 or 2) is worn. 3 · Device according to claim 1 and '2, characterized in that the contactor (10 or 20) has two contact tongues (7 «8 or 17» i8) which are arranged in an elastic insulation sheath (10 'or 20'), preferably made of plastic material, which are located at right angles to the friction surface (15a ¹ or 15b ¹ ) of the friction linings (15a or 15b) or the friction linings (15a, 15b) acting pressure can be brought into electrically conductive contact with one another. 4. Device according to claim 1 to 3 » characterized in that one of the contact tongues (7, 8) an electrically conductive connection with electrical Mass via a carrier part (3) of the friction lining carrier (1 or 2) having. 5. Apparatus according to claim 1 to k, characterized in that one of the contact tongues (7, 8) has an electrically conductive connection with a pad retaining pin (3). 6. Apparatus according to claim 1 to 3, characterized in that both contact tongues (171 i8) are connected to the electrical circuit by means of electrical cables (21, 22) « ■ 7 «device according to one of claims 1 to 6, characterized in that the contactor (10 or 20) is buttoned onto the bow of the expanding spring (6). 8. Device according to one of the preceding claims, characterized in that the contactor (1O or 20) opposite a TrMgertell t-3) the friction lining carrier (1 or 2) is fixed. ^ · ■ "" ■ "-" ■ - ^: - ■■ "■ ^;"; ΐΑ '# ί .; ■■■. "" - - 1941640 9 · Device according to claim 8,. characterized in that the contactor (10 or 20) is fixed with respect to a pad retaining pin (?). 10. Device according to claim 8 or 9 »' characterized in that the contactor (10 or 20) force-fit under the effect of the pressure of the expanding spring (6) is kept fixed. 11. Device according to one of claims 1 to 10, characterized in that the contactor (10) approximately in Area of his facing away from the contact tongues (7 and 8) ™ free end approximately symmetrical to its central longitudinal line Has widenings (13). . 12. Device according to one of the preceding claims, characterized in that when the predetermined Wear value of a friction lining (15a or 15b) of the contactor (10 or 20) through the friction lining (15a or 15b) associated friction lining carrier (1 or 2) can be brought into the electrically conductive switching position. 13. Apparatus according to claim 12, characterized in that the contactor (10 or 20) Ik is arranged so that upon reaching the predetermined Wear value of a friction lining (15a or 15b) the associated contact tongue (7 or 8 or 17 or 18) of the contactor (10 or 20) through the friction lining carrier associated with this friction lining (I5a or 15b) coming into contact with it (1 or 2) can be brought into electrically conductive contact with the other contact tongue (8 or 7 or 18 or 17). 1098 11/0767
£ AÖ ORiGfNAL. 1 ¹ *. Device according to one of the preceding claims, characterized in that a device (21a or 21b) is provided for the optional setting of the desired distance value a (R ₁ or R_) corresponding to the predetermined wear value. 15 · Device according to claim 1 ^ and one of claims 12 or 13, characterized in that the friction lining carrier or carriers (1 or 2) on its or their side coming to rest on the contactor (10 or 20) each have a respective transverse to the friction surface (15a ¹ or 15b ¹ ) of the friction lining (15a or 15b) has or have adjustable pressure surface (21a 'or 21b ^1). 16. Device according to claim 15 » characterized in that the adjustable pressure "surface (21a ^1, 21b ¹⁾ by the tip of a in a direction transverse to the friction surface (15a * or 1'5b ^r) of the friction lining (I5a or 15b) extending threaded bore in the friction lining carrier (1 or 2) arranged screw (21a or 21b) is formed. 17 device according to one of the preceding claims, characterized in that the contactor (10 or 20) by means of known plug connections (9) to its electrical) connecting line (s) (11 or 21, 22) connected to the electrical circuit. 109811/0767