DE102014212674A1 - Disc brake and method for adjusting a disc brake - Google Patents

Abstract

It is a disc brake, in particular for braking a ring gear of a connected between a pulley for driving ancillary components of a motor vehicle and a drive shaft of a drive motor of a motor vehicle planetary gear provided with a fixed Aktorgehäuseteil an actuator for actuating the disc brake, attachable to the Aktorgehäuseteil support piece, said Abstützstück in an unattached state in the axial direction is movable relative to the Aktorgehäuseteil and is fixed in a fixed state at a constant distance to Aktorgehäuseteil with the Aktorgehäuseteil, a via a first spring member axially movably supported on the support piece brake caliper for braking a brake disc on a first axial side , A brake shoe axially supported on a second spring element relative to the brake caliper on the supporting piece brake shoe for braking the brake disc to one of the first Axials eite pioneering second axial side and a self-tapping threaded centering screw for attachment of the Abstützstücks with the Aktorgehäuseteil, wherein the centering screw has at least a portion of the self-tapping thread end piece, wherein the end piece has a substantially conical outer contour and the tail into a mounting opening of the support piece or the actuator housing part can be screwed in a self-tapping manner, wherein the attachment opening has an inner contour that at least partially corresponds to the outer contour of the end piece. Due to the self-tapping screwing of the conical end of the centering in the correspondingly shaped mounting hole, the support piece can be fixed in a tolerance-compensated axial misalignment compensating distance with the Aktorgehäuseteil without significantly changed during self-tapping screwing the found optimal axial distance between the support piece and the Aktorgehäuseteil so that during operation of the disc brake, a substantially simultaneous contact of the caliper and the brake shoe on the brake disc can be achieved, which allows a disc brake with a long service life.

Description

The invention relates to a disc brake and a method for adjusting a disc brake, with the aid of a brake disc, in particular a ring gear provided between a crankshaft of an internal combustion engine of a motor vehicle and a pulley for driving ancillaries planetary gear, with a substantially equal braking force on both axial sides of the Brake disc can be braked.

From the DE 101 48 961 A1 a belt drive with a pulley for driving ancillaries is known, which is connected via a planetary gear with a crankshaft of the internal combustion engine of a motor vehicle. The planetary gear has a ring gear, which can be braked by means of a belt freewheel to vary a gear ratio between the crankshaft and the pulley.

In a typical disc brake, a friction padded caliper and a brake shoe connected to a brake shoe can be axially displaced to press the brake caliper and the brake shoe against the brake disc for closing the disc brake and braking a brake disc. It is possible that the caliper and the brake shoe are supported on a support piece via a spring element to automatically press the caliper and the brake shoe in an open position after a braking operation. When the caliper and the brake shoe are supported on the same support piece and actuated by a common actuator of an actuator, the exact positioning of the support piece relative to an actuator housing of the actuator at a defined distance is particularly important so that the caliper and the brake shoe an equal clearance have, whereby existing space can be optimally used and when braking simultaneous contact of the caliper and the brake shoe can be achieved on the brake disc.

There is a constant need to improve the life of a disc brake.

It is the object of the invention to show measures that allow a disc brake with a long service life.

The object is achieved by a disc brake with the features of claim 1 and a method for adjusting a disc brake with the features of claim 10. Preferred embodiments of the invention are set forth in the dependent claims, each individually or in combination constitute an aspect of the invention can.

According to the invention, a disc brake, in particular for braking a ring gear of a connected between a pulley for driving ancillaries of a motor vehicle and a drive shaft of a drive motor of a motor vehicle planetary gear provided with a fixed Aktorgehäuseteil an actuator for actuating the disc brake, attachable to the Aktorgehäuseteil support piece, said Abstützstück in an unattached state in the axial direction relative to the Aktorgehäuseteil is movable and in a fixed state at a constant distance is fixed to the Aktorgehäuseteil with the Aktorgehäuseteil, a via a first spring member axially movably supported on the support piece brake caliper for braking a brake disc on a first axial side, via a second spring member relative to the brake caliper axially movably supported on the support piece brake shoe for braking the brake disc to a from the first axial side pioneering second axial side and a self-tapping threaded centering screw for attachment of the Abstützstücks with the Aktorgehäuseteil, wherein the centering screw has at least a portion of the self-tapping end piece, wherein the end piece has a substantially conical outer contour and the tail in a Attachment opening of the support piece or the Aktorgehäuseteils is self-tapping screwed, wherein the attachment opening to the Außenkontor the tail at least partially corresponding inner ontur.

The disc brake can be closed in the unfastened state of the support piece, wherein the spring elements can apply a correspondingly increased spring force on the support piece, as a result of which the support piece can be automatically moved to an axial distance to Aktorgehäuseteil in which a actuation of the caliper and the brake shoe between a opened and a closed position is substantially equal and the support piece between the caliper and the brake shoe can be centered. For example, a tolerance-related axial offset of the brake disc and / or parts of the disc brake can be compensated automatically, without it being necessary for this to compensate for axial misalignment intermediate discs provided ("Shimmers"). In the closed position of the disc brake, the support piece can be connected to the actuator housing part by the self-tapping screwing of the centering screw into the fastening opening and fixed to the actuator housing part with the actuator housing part on the spacing of the support piece that adjusts in the closed state of the disc brake. For this purpose, for example, the centering screw in an internal thread of Aktorgehäuseteils regularly, that is non-self-tapping, be screwed and be screwed self-tapping in the provided in the support piece mounting opening. Alternatively, the centering screw in an internal thread of the support piece can be regular, that is non-self-tapping, screwed and be screwed self-tapping in the mounting opening provided in the actuator housing part.

Due to the conical outer contour of the end piece and the corresponding inner contour of the fastening opening, it is possible that the cutting edge of the self-tapping thread does not abut flat against a side edge of the thread on the edge of the fastening opening facing the centering screw. Instead, the centering screw with at least one cutting edge already inside the fastening opening can contact the inner surface of the fastening opening essentially from radially inward, so that, in particular, forces of the centering screw on the fastening opening in the axial direction can be avoided. In particular, in a further screws of the centering a force in the radial direction greatly increase, so that already can set a sufficiently high frictional force, which avoids an axial pushing away the mounting hole, in particular against the engaging spring forces of the spring elements. Instead, the force can increase in the radial direction to such an extent that the centering screw can screw self-tapping into the fastening opening, without the axial relative position of the support piece to the actuator housing part being significantly changed during the self-tapping screwing. It can thereby be achieved that in the fixed state of the Abstützstücks with the Aktorgehäuseteil at subsequent actuations of the disc brake on both the caliper and the brake shoe substantially equal normal forces and braking forces occur so that brake pads of the caliper and the brake shoe uniformly wear and essentially the entire wear reserve of the brake pads of the caliper and the brake shoe can be used. Due to the self-tapping screwing of the conical end of the centering in the correspondingly shaped mounting hole, the support piece can be fixed in a tolerance-compensated axial misalignment compensating distance with the Aktorgehäuseteil without significantly changed during self-tapping screwing the found optimal axial distance between the support piece and the Aktorgehäuseteil so that during operation of the disc brake, a substantially simultaneous contact of the caliper and the brake shoe on the brake disc can be achieved, which allows a disc brake with a long service life.

The actuator of the disc brake, for example, have a driven by an electric motor spindle drive to pivot an actuating lever, the brake caliper and the brake shoe for a brake closing in the axial direction towards each other via a ramp system and / or for opening the brake in axial Can shift direction away from each other. In particular, the actuator can have a housing which has the actuator housing part and can be mounted securely in position in the motor vehicle. For example, the housing can be fixedly connected to the drive motor, in particular an internal combustion engine, of the motor vehicle. If no actuating force is introduced into the disc brake by the actuator, then the first spring element, the brake caliper and the second spring element press the brake shoe in a defined starting position, which corresponds in particular to the open position of the disc brake. Since both the brake caliper and the brake shoe can be displaced axially relative to the brake disc, there is a floating connection of the caliper and the brake shoe to the support piece via the interposed respective spring element. As a result, the brake disk can be designed to be fixed and axially immovable in the axial direction, so that tilting moments and imbalances caused, for example, by an axial mobility of the brake disk can be avoided. Due to the very exact substantially central positioning of the support piece between the preferably equally thick friction linings of the caliper and the brake shoe, the caliper and the brake shoe in the open state may have a substantially equal distance from the brake disc. This allows a simultaneous contact of the caliper and the brake shoe to the brake disc at a closing of the disc brake and a similar wear of the caliper and the brake shoe to the brake disc.

The spring elements may in particular be designed as a spiral spring, wherein a plurality of coil springs inserted into each other and / or can be positioned side by side to provide a desired spring characteristic can. The attachment opening may in particular be a conically tapered part, a bore, in particular a through hole, which can be produced, for example, with the aid of a countersink. By way of example, the end piece of the centering screw can have an insertion pin with the aid of which the centering screw can be easily aligned coaxially with the fastening opening and, in particular, stabilized during the self-tapping screwing. An inclination and / or a tilting of the centering screw within the mounting hole can be avoided, so that acting on the mounting hole axial forces can be kept low by the centering. The outer contour of the end piece of the centering screw is understood, in particular, to mean an envelope which is guided along the radially outwardly pointing cutting edges of the thread and essentially corresponds to a truncated cone in the region of the thread. In particular, the end piece can have a truncated cone-shaped basic body, from which the thread protrudes at a constant thread height between the base body and the radially outer cutting edge. Alternatively, the base body can be made substantially cylindrical and the thread height of the thread in the radial direction projecting from the base body can change along the thread pitch such that a frustoconical outer contour results when viewing a longitudinal section of the centering screw. Preferably, the thread pitch in the region of the end piece and a central region adjoining the end piece is substantially constant. The center region of the centering screw may have a base body with a constant diameter, so that the central region for a regular, that is non-furrow, screw can be screwed into an internal thread of a component that is different from a component having the attachment opening.

In particular, contacted at a first contact of the tail of the centering with the mounting hole, a cutting edge of more than one turn at the same time the mounting hole. The geometric configuration of the end piece and the attachment opening are in particular prepared such that at a first contact of the end piece of the centering with the attachment opening a blade of more than one thread simultaneously contacted the attachment opening. Due to the plurality of cutting edges coming into contact with the inner surface of the fastening opening, at least two contact points arranged axially one behind the other between the inner surface of the fastening opening and the cutting edges of the thread of the centering screw, so that a correspondingly higher frictional force against an axial relative movement of the mounting hole to the centering screw and thus may result against an axial relative movement of the support piece to Aktorgehäuseteil.

Preferably, the attachment opening is formed of a softer material than the centering screw. A plastic deformation of the self-tapping thread of the centering can be avoided, so that the cutting edges of the thread can cut particularly far into the softer material of the mounting hole. This allows a sufficiently stable fixation of the support piece with the actuator housing part.

Particularly preferably, the outer contour of the end piece is beveled against an axis of the centering screw by an angle φ, wherein 0.0 ° <φ ≤ 25 °, in particular 0.5 ° ≤ φ ≤ 10 °, preferably 1.0 ° ≤ φ ≤ 5, 0 ° and more preferably 1.5 ° ≤ φ ≤ 2.5 ° applies. At such a comparatively shallow angle φ results in the truncated conical end portion of the centering only a relatively small deviation from a cylindrical outer contour. In particular, characterized by the radially outwardly facing force component in a striking and / or contacting the self-tapping thread on the mounting hole is particularly large compared to a pointing in the axial direction force component. Pressing out the Abstützstücks from the found equilibrium position when screwing the centering in the mounting hole is thereby avoided.

In particular, the centering screw and the attachment opening are arranged substantially coaxially. As a result, it is not necessary for the centering screw to exert a force in the radial direction and / or in the circumferential direction on the fastening opening in order to align the support piece and the actuator housing part for the screw connection to one another.

Preferably, the self-tapping thread for forming more than one pointing in the direction of thread cutting edge recesses. The thread can be interrupted along its helical course by a radially outwardly to radially inwardly extending recess, so that several circumferentially facing cutting edges can result. The cutting of the centering in the mounting hole can thereby begin at several defined locations simultaneously, which are preferably distributed uniformly in the circumferential direction. An inclination of the centering screw during cutting can be avoided.

Particularly preferably, the centering screw has a central region for forming a regular, in particular non-furrow, screw connection with the actuator housing part or with the support piece. The centering can be screwed with a little effort over the central region, so that the centering screw can not fall out during assembly. The centering screw can thereby be provided preassembled in the actuator housing part or in the support piece.

In particular, the first spring element and the second spring element have a substantially identical spring characteristic. The caliper and the brake shoe experienced by an equal stroke between the closed position and the open position of the disc brake.

The invention further relates to a pulley arrangement, in particular for connection to a crankshaft of an internal combustion engine of a motor vehicle, with a pulley for driving ancillaries, a ring gear having a ring gear for transmitting torque from a drive shaft, in particular crankshaft of an internal combustion engine of a motor vehicle, to the pulley, and a disc brake, which may be formed and further formed as described above, for braking the ring gear via a brake disc connected to the ring gear. By means of the disc brake, a sufficiently large drag torque can be applied to the ring gear in order to provide a reduction of, for example, 3: 1 between the drive shaft and the belt pulley for the planetary gear. If a torque is introduced via the pulley with the aid of a starter, this transmission ratio can facilitate the starting of the internal combustion engine. In normal operation, a gear ratio of 1: 1 can be set, whereby it is only necessary to disengage the disc brake. The disc brake need not be actuated in the normal driving operation of a motor vehicle, so that component loads are avoided and / or actuation energy for actuating the disc brake is not required. Due to the self-tapping screwing of the conical end of the centering in the correspondingly shaped mounting hole, the support piece can be fixed in a tolerance-compensated axial misalignment compensating distance with the Aktorgehäuseteil without significantly changed during self-tapping screwing the found optimal axial distance between the support piece and the Aktorgehäuseteil so that during operation of the disc brake, a substantially simultaneous contact of the caliper and the brake shoe to the brake disk can be achieved, which enables a pulley arrangement with a long service life.

The invention further relates to a method for adjusting a disc brake, which may be formed and further formed as described above, wherein the centering screw is screwed to the mounting opening spaced in the Aktorgehäuseteil or in the support piece, the disc brake is closed until both the caliper and Contact the brake shoe, the brake disk and then the support piece is fixed on the self-adjusting axial distance to the Aktorgehäuseteil by self-tapping screwing the centering into the mounting hole with the actuator housing part. Due to the self-tapping screwing of the conical end of the centering in the correspondingly shaped mounting hole, the support piece can be fixed in a tolerance-compensated axial misalignment compensating distance with the Aktorgehäuseteil without significantly changed during self-tapping screwing the found optimal axial distance between the support piece and the Aktorgehäuseteil so that during operation of the disc brake, a substantially simultaneous contact of the caliper and the brake shoe on the brake disc can be achieved, which allows a disc brake with a long service life.

The invention will now be described by way of example with reference to the accompanying drawings, in which the features shown below may represent an aspect of the invention both individually and in combination. Show it:

1 FIG. 2 is a schematic diagram of a part of a disk brake before being fixed; FIG.

2 : A schematic diagram of the disc brake off 1 during fixation,

3 : A schematic diagram of the disc brake off 1 after fixing,

4 : a schematic perspective view of a disc brake,

5 : A schematic sectional view of the disc brake off 4 before fixing and

6 : A schematic sectional view of the disc brake off 4 after fixing.

At the in 1 greatly simplified illustrated disc brake 10 is a centering screw 12 in their middle area 14 over a thread 16 for example, in an actuator housing part 18 screwed. The centering screw 12 has a conical tail 20 on, in a correspondingly shaped conical mounting hole 22 a support piece 24 can be screwed in self-tapping. The outer contour of the tail 20 is against a longitudinal axis 25 the centering screw 12 beveled by an angle φ, wherein the angle φ in 1 to 3 from founder of the better vividness is shown greatly exaggerated. If the disc brake 10 for an adjustment of an optimal axial distance of the support piece 24 to the Aktorgehäuseteil 18 is closed for the first time, is the centering screw 12 initially only so far in the Aktorgehäuseteil 18 screwed in that a contact of the centering screw 12 with the mounting hole 22 safely avoided ( 1 ). Then the centering screw 12 so far in the actuator housing part 18 screwed in until the end piece 20 provided thread 16 the centering screw 12 the mounting hole 22 contacted in several places at the same time ( 2 ). For a further screwing in the centering screw 12 can the self-tapping thread 16 in the mounting hole 22 of the support piece 24 dig in, without this the support piece 24 from the actuator housing part 18 is pushed away ( 3 ). This will be the support piece 24 safe with actuator housing part 18 on the first time closing the disc brake 10 fixed distance resulting.

As in 4 the disc brake can be shown 10 a caliper 26 have, over several first spring elements 28 on the support piece 24 is relatively movably supported in the axial direction. In addition, there is a brake shoe 30 provided, which has several second spring elements 32 on the support piece 24 is relatively movably supported in the axial direction. The caliper 26 and the brake shoe 30 each have a wear-affected friction lining 34 on to between the caliper 26 and the brake shoe 30 to brake a brake disc, not shown frictionally. With the help of an actuatable by an actuator lever 36 can via a ball ramp 38 the caliper 26 against the spring force of the first spring elements 32 and the brake shoe 30 against the spring force of the second spring elements 32 be moved towards each other in the axial direction to the disc brake 10 close. As in 5 and 6 represented can the brake shoe 30 via an axial sliding bearing 40 in the caliper 26 be guided axially. In the in 5 and 6 embodiment shown has the centering screw 12 in the area of the tail 20 a cylindrical body on which the thread 16 protrudes with a varying in axial direction thread height to the tail 20 to provide a cone-shaped outer contour, the cone-shaped inner contour of the attachment opening 22 equivalent.

LIST OF REFERENCE NUMBERS

10

 disc brake

12

 centering

14

 the central region

16

 thread

18

 Aktorgehäuseteil

20

 tail

22

 fastening opening

24

 support piece

25

 longitudinal axis

26

 caliper

28

 first spring element

30

 brake shoe

32

 second spring element

34

 friction lining

36

 actuating lever

38

 ball ramp

40

 axial plain

φ

 angle

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10148961 A1 [0002]

Claims (10)

Disc brake, in particular for braking a ring gear of a connected between a pulley for driving ancillaries of a motor vehicle and a drive shaft of a drive motor of a motor vehicle planetary gear, with a fixed actuator housing part ( 18 ) of an actuator for actuating the disc brake ( 10 ), one with the Aktorgehäuseteil ( 18 ) attachable support piece ( 24 ), wherein the support piece ( 24 ) in an unattached state in the axial direction relative to the Aktorgehäuseteil ( 18 ) is movable and in a fixed state at a constant distance to the Aktorgehäuseteil ( 18 ) with the actuator housing part ( 18 ) is fixed, one via a first spring element ( 28 ) axially movable on the support piece ( 24 ) supported caliper ( 26 ) for braking a brake disk on a first axial side, one via a second spring element ( 32 ) relative to the caliper ( 26 ) axially movable on the support piece ( 24 ) supported brake shoe ( 30 ) for braking the brake disk on a second axial side facing away from the first axial side and a self-tapping thread ( 16 ) having centering screw ( 12 ) for fixing the support piece ( 24 ) with the actuator housing part ( 18 ), whereby the centering screw ( 12 ) at least a part of the self-tapping thread ( 16 ) end piece ( 20 ), wherein the end piece ( 20 ) has a substantially conical outer contour and the tail ( 20 ) in a mounting opening ( 22 ) of the support piece ( 24 ) or the actuator housing part ( 18 ) is screwed in self-tapping, wherein the attachment opening ( 22 ) one to the Außenkontor the tail ( 20 ) has at least partially corresponding inner contour. Disc brake according to claim 1, characterized in that upon initial contact of the end piece ( 20 ) of the centering screw ( 12 ) with the attachment opening ( 22 ) a cutting edge of more than one thread at the same time the mounting hole ( 22 ) contacted. Disc brake according to claim 1 or 2, characterized in that the fastening opening ( 22 ) made of a softer material than the centering screw ( 12 ) is trained. Disc brake according to one of claims 1 to 3, characterized in that the outer contour of the end piece ( 20 ) against a longitudinal axis ( 25 ) of the centering screw ( 12 ) is bevelled by an angle φ, wherein 0.0 ° <φ ≤ 25 °, in particular 0.5 ° ≤ φ ≤ 10 °, preferably 1.0 ° ≤ φ ≤ 5.0 ° and particularly preferably 1.5 ° ≤ φ ≤ 2.5 ° applies. Disc brake according to one of claims 1 to 4, characterized in that the centering screw ( 12 ) and the attachment opening ( 22 ) are arranged substantially coaxially. Disc brake according to one of claims 1 to 5, characterized in that the self-tapping thread ( 16 ) has recesses for the formation of more than one pointing in the direction of the thread cutting edge. Disc brake according to one of claims 1 to 6, characterized in that the centering screw ( 12 ) a middle area ( 14 ) for forming a regular, in particular non-furrow, screw connection with the actuator housing part ( 18 ) or with the support piece ( 24 ) having. Disc brake according to one of claims 1 to 7, characterized in that the first spring element ( 28 ) and the second spring element ( 32 ) have a substantially same spring characteristic. Pulley arrangement, in particular for connection to a crankshaft of an internal combustion engine of a motor vehicle, with a pulley for driving ancillaries, a ring gear having a ring gear for transmitting torque from a drive shaft, in particular crankshaft of an internal combustion engine of a motor vehicle, to the pulley, and a disc brake ( 10 ) according to one of claims 1 to 8 for braking the ring gear via a brake disc connected to the ring gear. Method for adjusting a disc brake ( 10 ) according to one of claims 1 to 6, wherein the centering screw ( 12 ) to the attachment opening ( 22 ) spaced in the actuator housing part ( 18 ) or in the supporting piece ( 24 ), the disc brake ( 10 ) is closed until both the caliper ( 26 ) as well as the brake shoe ( 30 ) Contact the brake disc and then the support piece ( 24 ) on the self-adjusting axial distance to the Aktorgehäuseteil ( 18 ) by self-tapping screwing the centering screw ( 12 ) in the mounting opening ( 22 ) with the actuator housing part ( 18 ) is fixed.

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