Disc Brake With a Synchronization Mechanism

Abstract

A disc brake, for a motor vehicle, has a brake caliper with a clamping section, which is equipped with a clamping device with a brake rotary lever, at least two threaded pistons, an adjustment device, and a driver device. A synchronization mechanism for synchronizing the rotational movements of the threaded pistons is arranged outside of the housing of the brake caliper within a sealed cover on the clamping section of the brake caliper. The synchronization mechanism has at least one synchronizing element and two synchronizing wheels, a first synchronizing wheel of which is coupled to one threaded piston and a second synchronizing wheel of which is coupled to the other threaded piston. The synchronization mechanism is arranged on the clamping section of the brake caliper (3) so as to be guided about a lever housing of the brake rotary lever. The lever housing protrudes from the clamping section of the brake caliper.

Claims

1.-14. (canceled)

15. A disc brake for a motor vehicle, comprising: a brake caliper having a clamping section housing in which a clamping device with a brake rotary lever, at least two threaded pistons, an adjustment device, and a driver device are arranged; and a synchronization mechanism for synchronizing rotational movements of the at least two threaded pistons, wherein the synchronization mechanism is arranged outside the housing within a sealed cover, wherein the synchronization mechanism comprises: at least one synchronizing element and two synchronizing wheels, the two synchronizing wheels being respectively connected to the two threaded pistons in a rotationally fixed manner, and wherein the synchronization mechanism is arranged on the clamping section housing of the brake caliper so as to be guided about a lever housing of the brake rotary lever, which lever housing protrudes from the clamping section housing of the brake caliper.

16. The disc brake according to claim 15, wherein the brake caliper has a balcony-shaped support section which is attached or integrally formed laterally to the clamping section housing, the support section protrudes from the clamping section housing of the brake caliper in a direction orthogonal to a brake disc axis, wherein an upper side of the support section extends in a common plane together with an end face of the clamping section housing.

17. The disc brake according to claim 16, wherein the support section is an additional cast contour of the clamping section housing of the brake caliper.

18. The disc brake according to claim 16, wherein the at least one synchronizing element of the synchronizing mechanism is a chain, a roller chain, or a toothed belt, and interacts with the two synchronizing wheels as a wrap-around gear, and the synchronizing mechanism is arranged inside the sealed cover on the clamping section housing and on the support section of the brake caliper.

19. The disc brake according to claim 18, wherein the at least one synchronizing element is arranged around the lever housing of the brake rotary lever with the aid of a chain guide.

20. The disc brake according to claim 19, wherein the chain guide has guide elements in the form of cylindrical domes, deflection rollers and/or guide rails.

21. The disc brake according to claim 16, wherein a course of the at least one synchronizing element around the lever housing of the brake rotary lever is a component of an imaginary trapezoidal shape, the course of the synchronizing element is arranged in an area of slanted edges of the support section, which form components of legs of the imaginary trapezoid, and of a straight edge of the support section, which is a short base side of the imaginary trapezoid.

22. The disc brake according to claim 16, wherein the at least one synchronizing element of the synchronizing mechanism is formed from a number of synchronizing gears, and interacts with the two synchronizing wheels that form spur gears, the synchronizing mechanism is arranged within the sealed cover on the clamping section housing and on the support section of the brake caliper.

23. The disc brake according to claim 16, wherein the at least one synchronizing element of the synchronization mechanism is formed from a number of synchronizing shafts which are coupled to one another and to the two synchronizing wheels via coupling units which are attached, in each case, to ends of the synchronizing shafts.

24. The disc brake according to claim 23, wherein the coupling units have bevel gears, and the two synchronizing gears are crown gears with bevel teeth.

25. The disc brake according to claim 23, wherein the coupling units have universal joints, constant velocity joints, or elastic coupling elements.

26. The disc brake according to claim 16, wherein the at least one synchronizing element of the synchronization mechanism is formed from one or more flexible shafts.

27. The disc brake according to claim 15, wherein the clamping section housing together with the support section is formed in one piece as a monobloc caliper.

28. The disc brake according to claim 15, wherein the brake caliper together with the support section is formed in one piece as a monobloc caliper.

29. The disc brake according to claim 15, wherein the disc brake is a compressed air actuated disc brake.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0052] FIG. 1 shows a schematic sectional view of a disc brake from the prior art;

[0053] FIGS. 2-3 show schematic perspective views of embodiment variants of disc brakes from the prior art;

[0054] FIGS. 4-5 show schematic views of conventional synchronization mechanisms of disc brakes from the prior art;

[0055] FIG. 6 shows a schematic perspective view of an exemplary embodiment of a disc brake according to the invention with a synchronization mechanism according to an embodiment of the invention;

[0056] FIG. 7 shows an enlarged sectional view of a lever housing of a brake caliper of the exemplary embodiment according to FIG. 6;

[0057] FIG. 8 shows a schematic perspective view of the exemplary embodiment of the disc brake according to the invention as shown in FIG. 6; and

[0058] FIGS. 9-10 show schematic perspective views of variants of the exemplary embodiment shown in FIG. 6.

DETAILED DESCRIPTION OF THE DRAWINGS

[0059] FIGS. 1 to 5 from the prior art have already been described above.

[0060] FIG. 6 shows a schematic perspective view of a synchronization mechanism 12 of the exemplary embodiment according to FIG. 6. FIG. 7 shows an enlarged sectional view of a lever housing 3c of a brake caliper 3 of the exemplary embodiment of the disc brake 1 according to the invention according to FIG. 6. FIG. 8 shows a schematic perspective view of an exemplary embodiment of a disc brake 1 according to the invention in a top view.

[0061] As shown in FIG. 6, the lever housing 3c of the brake rotary lever 11 of the radial brake, i.e. disc brake 1, protrudes in the direction of the brake disc axis 2a from the clamping section 3a of the brake caliper 3. The lever housing 3c is arranged in the middle of the end face 18 of the clamping section 3a between the adjuster axis 9a and the driver axis 10a.

[0062] The brake rotary lever 11 is arranged in the lever housing 3c. In FIG. 6, the end of the lever arm of the brake rotary lever 11 can be seen inside an opening of the flange section 3b. This end of the lever arm interacts with the plunger of the brake cylinder 17 to be attached to the flange section 3b.

[0063] To ensure that the design of the rotary brake rotary lever 11 is as simple and compact as possible, the transmission mechanism of the synchronization mechanism 12 must be routed around the brake rotary lever 11 and its lever housing 3c. On the other hand, due to restrictions regarding the installation of the disc brake in a vehicle, the synchronization mechanism 12 must be arranged in such a way that the permissible installation space for the disc brake 1 in the vehicle is not exceeded.

[0064] The synchronization mechanism 12 is therefore arranged so that it is located outside the wheel rim and on the side of the caliper housing of the brake caliper 3 facing away from the axle beam of the vehicle.

[0065] Guiding the synchronization mechanism 12 around the lever housing 3c requires an extension of a surface of the end face 18. For this purpose, the brake caliper 3 has a balcony-like support section 19 attached to the side of the clamping section 3a. This support section 19 protrudes from the clamping section 3a of the brake caliper 3 in the direction of the brake disc axis 2a.

[0066] An upper side 20 of the support section 19 extends in a common plane together with the end face 18 of the clamping section 3a and forms an extension to it.

[0067] The support section 19 also serves to support a cover 21, which protects the synchronization mechanism. Sealing of the cover 21 is made possible by a cover seal 21a, which is inserted or applied in a suitable manner, e.g. in matching contours, in the edge region of the upper side 20 of the support section 19 and on the end face 18 of the clamping section 3a.

[0068] The support section 19 can, for example, be an additional cast contour of the clamping section 3a of the brake caliper 3.

[0069] To this end, FIG. 7 shows an enlarged sectional view of the lever housing 3c of the brake caliper 3 of the exemplary embodiment according to FIG. 6. The brake rotary lever 11 with its lever arm and its end are arranged in a slender shape in the lever housing 3c. The brake rotary lever 11 can be rotated about a rotary lever axis 11a, which here extends at an angle of 90 to the brake disc axis 2a.

[0070] The support section 19 is formed in one piece with the clamping section 3a of the brake caliper 3.

[0071] The support section 19 can be arranged on the edge of the clamping section 3a along the entire length of the edge or over a shorter length. Different geometric shapes of the support section 19 are possible. For example, FIG. 6 shows a trapezoidal shape, FIG. 9 curved sections with different radii and straight extensions. Rectangular shapes are also conceivable. The edges of these shapes are provided with partially cylindrical domes, which are used to attach the fastening elements 22 of the cover 21. It is understood that other edge shapes are also possible.

[0072] FIG. 8 shows the brake caliper 3 as a monobloc caliper. The synchronization mechanism 12 is closed with the cover 21. The cover 21 is fastened to the support section 19 at its circumferential edge with fastening elements 22, 22a, 22b, 22c and 22, 22a, 22b, 22c, e.g. screws. In the example shown, the cover 21 and the synchronization mechanism 12 are symmetrical with respect to an axis of symmetry which extends parallel to the brake disc axis 2a through the center of an imaginary connecting line of adjuster axis 9a and driver axis 10a.

[0073] As with the axial brake (see FIG. 4) and as a transmission element, a roller chain serves as a synchronizing element 13. The threaded pistons 7, 8 (see FIG. 1) are indicated in FIG. 5 and in the other figures by the adjuster axis 9a and the driver axis 10a. In this case, the two threaded pistons 7, 8 cannot be coupled directly to the roller chain. The term direct path is to be understood as an imaginary straight line between the axes 9a and 10a, which is blocked here by the lever housing 3c protruding from the clamping section 3a of the brake caliper 3.

[0074] Due to the conditions described above, the synchronizing element 13 (chain) must be guided around the lever with the aid of a chain guide. This chain guide has guide elements 23, 23a in the form of cylindrical domes and guide rails.

[0075] A course of the synchronizing element 13 on the end face 18 of the clamping section 3a and the upper side of the support section 19 around the lever housing 3c can be described as part of an imaginary trapezoidal shape. This imaginary trapezoid is formed by a long base side between the adjuster axis 9a and the driver axis 10a. The shorter base side extends parallel to this as the free edge 19a of the support section 19. The legs of the imaginary trapezoid are formed from the slanted edges 19b, 19c of the support section 19.

[0076] In this case, the course of the synchronizing element 13 is arranged in the area of the slanted edges 19b, 19c and the straight edge 19a.

[0077] It is important here that the chain is guided as a synchronizing element 13 with as little friction as possible so that the transmission losses caused by the friction of the chain at the deflection points of the domes are not too great. The larger the deflection angles, the greater the transmission losses can be. The relationship can be described using the rope friction equation.

[00001]$F_1=F_2*e^{}$

[0078] Wherein: [0079] F.sub.1: Tensile force on the chain after deflection [0080] F.sub.2: Tensile force on the chain before the deflection [0081] : Deflection angle [0082] : Coefficient of friction

[0083] To minimize transmission losses, the chain can also be deflected using deflection rollers. However, the applicability of this solution depends on the available installation space.

[0084] Instead of a roller chain, a toothed belt can also be used as synchronizing element 13. This is not shown, but is easily understood. In this case, the synchronizing wheels 14, 15 are correspondingly designed as toothed belt wheels.

[0085] FIG. 9 shows a schematic perspective view of a first variant of the exemplary embodiment shown in FIG. 6.

[0086] In this first variant, a number of synchronizing gears 24, 25, 25a, e.g. spur gears, are used as the synchronizing element 13. In the example shown in FIG. 9, the synchronization mechanism 12 comprises five synchronizing gears 24, 25, 25a and two synchronizing wheels 14, 15.

[0087] The synchronizing wheels 14, 15 are designed here as spur gears and are each in mesh with a first synchronizing gear 24. These first synchronizing gears 24 are each in mesh with a second synchronizing wheel 25, which in turn are both in mesh with a common synchronizing wheel 25a. An odd number of synchronizing gears 24, 25, 25a is required in order to obtain the same direction of rotation of the threaded pistons 7, 8, otherwise the thread of one of the threaded pistons 7, 8 would have to be a left-hand thread.

[0088] In contrast to the synchronizing element 13 as a roller chain, the transmission losses in this variant are hardly influenced by the size of the deflection, i.e. by the angle between the sides of the imaginary trapezoid. The transmission losses are mainly determined by the number of synchronizing gears 24, 25, 25a.

[0089] In a second variant of the exemplary embodiment according to FIG. 6, which is shown in a schematic perspective view in FIG. 10, shafts are used as synchronizing elements or transmission elements, which are designated here as synchronizing shafts 26, 26, 26.

[0090] In the example shown, the synchronization mechanism 12 comprises three synchronizing shafts 26, 26, 26, four coupling units and two synchronizing wheels 14, 15.

[0091] The synchronizing shafts 26, 26, 26 are coupled to each other and to the synchronizing wheels 14, 15 via the coupling units with bevel gears or also other coupling elements (e.g. universal joints, constant velocity joints or elastic coupling elements), which are each attached to the ends of the synchronizing shafts 26, 26, 26.

[0092] The synchronizing shafts 26, 26, 26 are each attached to the end face 18 of the clamping section 3a and the upper side 20 of the support section 19 via a bearing 28, 28, 28 not described in detail.

[0093] In this variant, the arrangement of the three synchronizing shafts 26, 26, 26 is such that two synchronizing shafts 26, 26, which are each coupled to a synchronizing wheel 14, 15, extend in the inclined sides of an imaginary trapezoid. One synchronizing shaft 26, which is coupled to the two other synchronizing shafts 26, 26, extends in the short base side of the imaginary trapezoid.

[0094] In this variant, the synchronizing wheels 14, 15 are designed as crown bevel gears. Accordingly, coupling wheels 27, 27a; 27, 27a; 27, 27a of the synchronizing shafts 26, 26, 26 are designed as bevel gears. The synchronizing wheels 14, 15 are bevel gears with bevel teeth.

[0095] The first synchronizing wheel 14 is in mesh with a coupling wheel 27 of the first synchronizing shaft 26. The other coupling wheel 27a of the first synchronizing shaft 26 and a coupling wheel 27 of the second synchronizing shaft 26 form the coupling of the synchronizing shafts 26 and 26. Similarly, the second synchronizing shaft 26 and the third synchronizing shaft 26 are coupled via their coupling wheels 27a and 27. The other coupling wheel 27a is in mesh with the second synchronizing wheel 15.

[0096] It is also contemplated to transmit the rotational movements of the threaded pistons 7, 8 by means of the synchronization mechanism with one or more flexible shafts.

[0097] The invention is not limited by the exemplary embodiments described above. It can be modified within the scope of the appended claims.

[0098] The course of the synchronizing element 13 as a chain can be designed as an arc shape with one radius or an arc shape consisting of several arcs with different radii. In this case, however, the dimension of the protrusion of the edge of the support section 19 from the clamping section 3a of the brake caliper 3 must be taken into account, as this may result in larger installation dimensions of the disc brake 1.

LIST OF REFERENCE SIGNS

[0099] 1 Disc brake [0100] 2 Brake disc [0101] 2a Brake disc axis [0102] 3 Brake caliper [0103] 3a Clamping section [0104] 3b Flange section [0105] 3c Lever housing [0106] 4, 5 Brake pad [0107] 6 Cross-member [0108] 7, 8 Threaded piston [0109] 9 Adjustment device [0110] 9a Adjuster axis [0111] 10 Driver device [0112] 10a Driver axis [0113] 11 Brake rotary lever [0114] 11a Rotary lever axis [0115] 12 Synchronization mechanism [0116] 13 Synchronizing element [0117] 14, 15 Synchronizing wheel [0118] 16 Cover [0119] 17 Brake cylinder [0120] 18 End face [0121] 19 Support section [0122] 19a, 19b, 19c Edge [0123] 20 Upper side [0124] 21 Cover [0125] 21a Cover seal [0126] 22, 22a, 22b; 22, 22a, 22b Fastening element [0127] 23, 23a Guide element [0128] 24, 25 Synchronizing gear [0129] 26, 26, 26 Synchronizing shaft [0130] 27, 27, 27; 27a, 27a, 27a Coupling wheel [0131] 28, 28, 28 Bearing [0132] B Base plate