Electromagnetically actuable brake device

Abstract

An electromagnetically actuable brake device includes: a coil shell, in particular of the solenoid, an armature disk, which is connected to the coil shell in a torque-proof yet displaceable manner, a sensor having a sensor housing, a spring part, and a screwed cable gland. The coil shell has a stepped through bore, the sensor housing of the sensor has a stepped configuration, the screwed cable gland is situated at an end of the bore, in particular is screwed into a threaded section of the bore, the spring part is situated in the bore between the screwed cable gland and the sensor housing, the spring part is braced on a step of the sensor housing on one side and on the screwed cable gland on the other, and the sensor housing is pressed against a step of the bore, in particular by the spring part.

Claims

1. An electromagnetically actuable brake device, comprising: a coil shell; an armature disk connected to the coil shell in a torque-proof and displaceable manner; a sensor having a sensor housing; a spring part; and a screwed cable gland; wherein the coil shell includes a stepped through bore, the sensor housing of the sensor being stepped, the screwed cable gland situated at an end of the bore, the spring part is arranged in the bore between the screwed cable gland and the sensor housing, one side of the spring part being braced on a step of the sensor housing, an opposite side of the spring part being braced on the screwed cable gland, the sensor housing being pressed against a step of the bore.

2. The device according to claim 1, wherein the sensor and the through bore are located at a greater radial distance from an axis of a shaft to be braked than a coil of a solenoid of the electromagnetically actuable brake device.

3. The device according to claim 1, wherein the bore is covered by the armature disk when the armature disk is resting against the coil shell.

4. The device according to claim 1, wherein a peripheral angular range covered by the armature disk covers a peripheral angular range covered by the bore, and a radial distance range covered by the armature disk covers a radial distance range covered by the bore.

5. The device according to claim 4, wherein no parts are located in an intermediate region between the armature disk and the sensor.

6. The device according to claim 1, further comprising a cable centrically routed from the sensor through the spring part and centrically through the screwed cable gland.

7. The device according to claim 1, wherein the sensor includes an eddy-current sensor.

8. The device according to claim 7, wherein the eddy-current sensor is adapted to sense a distance between the armature disk and the eddy-current sensor.

9. The device according to claim 1, wherein the coil shell is arranged as a coil shell of a solenoid.

10. The device according to claim 1, wherein the screwed cable gland is screwed into a threaded section of the bore.

11. The device according to claim 1, wherein the spring part is located axially between the screwed cable gland and the sensor housing.

12. The device according to claim 1, wherein the sensor housing is pressed against the step of the bore by the spring part.

13. An electromagnetically actuable brake device, comprising: a first coil shell; a second coil shell; a first armature disk connected to the first coil shell in a torque-proof and displaceable manner; a second armature disk connected to the second coil shell in a torque-proof and displaceable manner, a sensor having a sensor housing; a spring part; and a screwed cable gland; wherein the first coil shell includes a first through bore, the second coil shell includes a second through bore, the first through bore and second through bore being coaxially aligned with respect to each other, the second through bore being stepped, the sensor housing of the sensor being stepped, the screwed cable gland being arranged at an end of the first through bore facing away from the second coil shell, the spring part arranged in the first through bore or the second through bore between the screwed cable gland and the sensor housing; wherein (a) one side of the spring part is braced on a step of the sensor housing and an opposite side of the spring part is braced on a sleeve that touches the screwed cable gland at an end facing away from the spring part or (b) one side of the spring part is braced on the screwed cable gland and an opposite side of the spring part is braced on a sleeve that touches a step of the sensor housing; and wherein the sensor housing is pressed against a step of one of the through bores.

14. The device according to claim 13, wherein the first through bore and the second through bore are arranged at a same radial distance from a shaft to be braked and cover a same peripheral angular range.

15. The device according to claim 13, wherein the screwed cable gland is screwed into a threaded section of the first through bore.

16. The device according to claim 13, wherein the sensor housing is pressed against the step of one of the through bores by the spring part.

17. The device according to claim 13, wherein an axial region covered by the sleeve overlaps with an axial region covered by the first coil shell and the second coil shell.

18. The device according to claim 13, wherein the sleeve extends through a through bore of the first armature disk.

19. The device according to claim 13, wherein the sleeve is located at a greater radial distance from an axis of a shaft to be braked than a brake-pad carrier that is connected to the shaft to be braked in a torque-proof and axially displaceable manner.

20. The device according to claim 13, further comprising a cover connected to the first coil shell and to the second coil shell so that an intermediate region between the first coil shell and the second coil shell is surrounded by the cover.

21. The device according to claim 20, wherein the first armature disk is located in the intermediate region.

22. The device according to claim 13, further comprising a cover connected to the second coil shell and a part having a counter-brake surface so that an intermediate region between the part and the second coil shell is surrounded by the cover.

23. The device according to claim 22, wherein the second armature disk is located in the intermediate region.

24. The device according to claim 20, wherein the cover is (a) formed of a more elastic material than the coil shells and/or is (b) formed of (i) plastic and/or (ii) rubber.

25. The device according to claim 22, wherein the cover is (a) formed of a more elastic material than the coil shells and/or is (b) formed of (i) plastic and/or (ii) rubber.

26. The device according to claim 13, wherein the sensor and the through bores are located at a greater radial distance from an axis of a shaft to be braked than a coil of a solenoid of the electromagnetically actuable brake device.

27. The device according to claim 13, wherein the first and second through bores are covered by one of the first and second armature disks when the one of the first and second armature disks is resting against one of the coil shells.

28. The device according to claim 13, wherein a peripheral angular range covered by one of the first and second armature disks covers a peripheral angular range covered by the through bores, and a radial distance range covered by the one of the first and second armature disks covers a radial distance range covered by the through bores.

29. The device according to claim 28, wherein no part is located in an intermediate region between the one of the first and second armature disks and the sensor.

30. The device according to claim 13, further comprising a cable centrically routed from the sensor through the spring part and centrically through the screwed cable gland.

31. The device according to claim 13, wherein the sensor includes an eddy-current sensor.

32. The device according to claim 31, wherein the eddy-current sensor is adapted to sense the distance between one of the first and second armature disks and the eddy-current sensor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a brake device according to an example embodiment of the present invention including a sensor for wear detection, in a sectional view.

(2) FIG. 2 shows the sensor with an associated mounting system in an oblique view.

(3) FIG. 3 shows an alternative brake device equipped with a sensor for wear detection, in a sectional view.

(4) FIG. 4 shows the sensor associated with FIG. 3 with an associated mounting system, in an oblique view.

DETAILED DESCRIPTION

(5) As illustrated in FIG. 1 and FIG. 2, an electromagnetically actuable brake according to an example embodiment of the present invention is depicted.

(6) A brake-pad carrier 11 is connected to a shaft to be braked in a torque-proof yet axially displaceable manner. The shaft is mounted inside a housing part that is connected to coil shell 3 of a solenoid in a torque-proof manner.

(7) Brake-pad carrier 11 has an internal tooth system which is in engagement with an external tooth system disposed on the shaft. The tooth system extends in the axial direction so that brake-pad carrier 11 is able to be axially displaced in relation to the shaft.

(8) A coil brace 6, in which an energizable coil 7 is situated, is accommodated in an annular groove of coil shell 3. The ring axis of the annular groove is aligned coaxially with respect to the shaft axis.

(9) Brake-pad carrier 11 is provided with brake pads 9 axially on both sides. An armature disk 8 is situated axially between brake-pad carrier 11 and coil shell 3. For example, armature disk 8 is made from a ferromagnetic material. Armature disk 8 is connected to coil shell 3 in a torque-proof yet axially displaceable manner with the aid of guide elements, the armature disk being guided by the guide elements during the displacement.

(10) Spring elements are situated between coil shell 3 and armature disk 8. An approach of armature disk 8 toward coil shell 3 can therefore only take place counter to the force generated by the spring elements.

(11) When coil 7 is energized, armature disk 8 is pulled toward coil shell 3 counter to the spring force generated by the spring elements.

(12) In the non-energized state of coil 7, the spring elements axially press armature disk 8 in the direction of brake-pad carrier 11, the latter being axially displaced in the process and pressed against a part 10, which has a brake surface and is firmly connected to coil shell 3.

(13) In other words, in the non-energized state of coil shell 7, armature disk 8 is pushed away from coil shell 3 up to an axial stop position. The stop position is a function of the thickness of the brake pads. Depending on the wear, the axial distance between armature 8 and coil shell 3 thus differs in the non-energized state.

(14) To monitor wear, a sensor is provided for sensing this distance.

(15) The sensor is arranged as an eddy-current sensor.

(16) The housing of the sensor has a stepped outer contour.

(17) A through bore, in which the sensor is accommodated, is situated in coil shell 3. The bore also has a stepped configuration and has a cross-section that tapers in the direction of the armature disk. Via a corresponding step, housing 1 of the sensor rests against the step of the bore and includes a step 20 on the side facing away from this step and/or on the side facing away from armature disk 8. This step 20 leads from a first diameter to a second diameter which is smaller than the first diameter. The axial end region tapering in this manner is disposed at the end of sensor housing 1 facing away from armature disk 8.

(18) Sensor housing 1 may be arranged as a rotating body.

(19) Sensor cable 5 is centrally routed out of sensor housing 1. A spring part 2, arranged as a spiral spring, is accommodated in the bore and braced on step 20 of sensor housing 1. The end of the bore that faces away from armature disk 8 is sealed with the aid of a screwed cable gland 4, which presses against the end of spring part 2 facing away from step 20. Screwed cable gland 4 is connected by screws to an internal threaded section of the bore, or stated another way, is screwed into the bore. The internal threaded section extends only across an end section of the bore and not across the entire bore. This end section of the bore is situated in the end region of the bore that faces away from armature disk 8.

(20) Screwed cable gland 4 may be formed of metal.

(21) In the same manner, sensor housing 1 and spring part 2 are made from metal.

(22) When screwing screwed cable gland 4 into the bore, spring part 2 is tensioned and thus presses against sensor housing 1. Because of the preloading created in this manner, the sensor housing 1 is pressed against the step of the bore.

(23) Cable 5 is axially routed through spring part 2 in a centered manner and is then centrically routed through a recess in screwed cable gland 4 in the axial direction.

(24) Screwed cable gland 4 has a hexagonal shoulder 21, which limits the screwing-in of screwed cable gland 4 and is furthermore suitable for the positive application of an open end wrench. This makes it easy to screw screwed cable gland 4 into the threaded section of the bore.

(25) In contrast to the exemplary embodiment according to FIGS. 1 and 2, in the exemplary embodiment according to FIGS. 3 and 4 a sleeve 30 for spacing spring part 2 apart from sensor housing 1 is placed inside the bore.

(26) In this way the sensor is able to be installed on a second brake situated at a greater distance, sleeve 30 bridging a first brake.

(27) As illustrated in FIGS. 3 and 4, a first and a second electromagnetically operable brake are provided in the double brake.

(28) The first brake is arranged according to FIG. 1. The second brake has a similar configuration; here, the part of the second brake having a counter-brake surface is not a coil shell or need not be a coil shell, but may exemplarily be arranged as a bearing shield of an electric motor.

(29) In this case, a second coil shell 36 is used as the particular part 10 that has a brake surface for brake-pad carrier 11 with brake pad 9. Second coil shell 36 is firmly connected to coil shell 3 of the first brake, in particular connected with the aid of screws.

(30) Another annular groove, its ring axis being aligned coaxially with the shaft axis, is also situated in second coil shell 36.

(31) Once again, a coil brace 34, which accommodates a second coil 35, is accommodated in the annular groove of second coil shell 36.

(32) A second brake-pad carrier 11 is connected to the shaft in a torque-proof yet axially displaceable manner; the shaft has an axially extending external tooth system for this purpose, which is in engagement with an internal tooth system of brake-pad carrier 11. An armature disk 33 is axially situated between the second brake-pad carrier and second coil shell 36 and connected to second coil shell 36 in a torque-proof yet axially displaceable manner with the aid of guide elements. Second spring elements are situated between second armature disk 33 and second coil shell 36 so that when second coil 35 is energized, armature disk 33 is pulled toward coil shell 36 counter to the spring force generated by the second spring elements. In the non-energized state of second coil 35, second armature disk 33 is axially pushed away from second coil shell 36 and onto the second brake-pad carrier with brake pads. The second brake-pad carrier in turn is axially pressed onto a part having a counter-brake surface, the part being situated on the side of the second brake-pad carrier axially facing away from armature disk 33.

(33) A sensor for wear detection of the brake pads of the second brake is in turn disposed in a bore that is situated in coil shell 36 in an axially uninterrupted manner and has a stepped configuration; the narrower and/or tapered section of the bore is situated on the side facing second armature disk 33, and the section having the larger cross-section is situated on the side facing second armature disk 33.

(34) The bore, so to speak, continues through armature disk 8 of the first brake and through coil shell 3 of the first brake. The bores in armature disk 8 and coil shell 3 have a coaxial alignment and are arranged using at least the same cross-section.

(35) Thus, sensor housing 1 is pressed against the step of the bore implemented in second coil shell 36, and a corresponding step of the sensor housing is placed against the step of the bore introduced into second coil shell 36, or in other words, is pressed against it.

(36) A spring part 2 is in turn pressing against step 20 of sensor housing 1; however, at its axial end facing away from sensor housing 1, spring part 2 is braced on a sleeve 30, which is in turn braced at its axial end facing away from spring part 2 on screwed cable gland 4, which is screwed into coil shell 3 in the threaded section.

(37) This screwed cable gland is in turn resting against coil shell 3 via its shoulder 21.

(38) Sleeve 30 is hollow. Thus, cable 5 is centrically routed through spring part 2 and sleeve 30 so that it is likewise able to be centrically routed through the screwed cable gland and out of the interior space of the brake device in a sealed manner.

(39) The bore and sleeve 30 are situated at a radial distance from the shaft axis such that brake-pad carrier 11 together with brake pads 9 is radially situated within the bore and sleeve 30. The axial range covered by sleeve 30 covers the axial range covered by armature disk 8 and the axial range covered by brake-pad carrier 11 with brake pads 9, and it overlaps with the axial range covered by coil shell 3 and by second coil shell 36.

(40) Coil shell 3 and second coil shell 36 are connected with the aid of a cover 31, especially a rubber cover, so that the intermediate region situated axially between coil shell 3 and coil shell 36 is covered in the manner of a housing. Cover 31 has an annular design for this purpose and is placed in a nonpositive manner onto a subregion of the external surface of coil shell 3 and coil shell 36.

(41) Situated in the intermediate region are brake-pad carrier 11 together with brake pads 9 and armature disk 8. The region axially covered by cover 31 therefore covers the axial region covered by brake-pad carrier 11 together with brake pads 9 and the axial region covered by armature disk 8.

(42) In addition, when viewed from the direction of the shaft axis, cover 31 is situated radially outside brake-pad carrier 11 together with brake pads 9 and armature disk 8.

(43) Coil shell 36 and the part having the counter-brake surface are similarly connected with the aid of a cover 32, in particular a rubber cover, so that the second intermediate region that is situated axially between second coil shell 36 and the part having the counter-brake surface is covered in the manner of a housing. Cover 32 has an annular design for this purpose and is placed in a nonpositive manner on a subregion of the external surface of coil shell 36 and of the part having the counter-brake surface.

(44) Situated in the second intermediate region are the second brake-pad carrier together with the brake pads and second armature disk 33. As a result, the region axially covered by cover 32 covers the axial region covered by the second brake-pad carrier together with the brake pads and the axial region covered by armature disk 33.

(45) In addition, when viewed from the direction of the shaft axis, cover 32 is situated radially outside the second brake-pad carrier together with the brake pads and armature disk 33.

(46) Cover 31 may be arranged in the same manner as cover 32. As a result, only one type of cover needs to be stocked.

(47) Sleeve 30 is situated at a greater radial distance than coil 7, coil shell 6 and/or the annular groove in coil shell 3 and/or the annular groove in coil shell 36.

LIST OF REFERENCE NUMERALS

(48) 1 Sensor housing, stepped configuration 2 Spring part 3 Coil shell 4 Screwed cable gland 5 Cable 6 Coil brace 7 Coil, in particular brake coil 8 Armature disk 9 Brake pad 10 Part having the brake surface 11 Brake-pad carrier 20 Step 21 Shoulder 30 Sleeve 31 Cover, in particular rubber cover 32 Cover, in particular rubber cover 33 Further armature disk 34 Further coil brace 35 Further coil 36 Further coil shell