Abstract
A retaining device for coupling an encoder unit of a rotary encoder to an electric machine includes an end shield having a guide groove for receiving an encoder module of the encoder unit, and a retaining ring including a first coupling element for mechanically coupling the retaining ring to the end shield, with the first coupling element being embodied as a hole. A fastening screw is received in the hole to mechanically fasten the retaining ring to the end shield. A shielding element is integrally formed on the retaining ring for shielding against an external interference field.
Claims
1.-12. (canceled)
13. A retaining device for coupling an encoder unit of a rotary encoder to an electric machine, said retaining device comprising: an end shield having a guide groove for receiving an encoder module of the encoder unit; a retaining ring including a first coupling element for mechanically coupling the retaining ring to the end shield, said first coupling element being embodied as a hole; a first fastening screw received in the hole to mechanically fasten the retaining ring to the end shield; and a shielding element integrally formed on the retaining ring for shielding against an external interference field.
14. The retaining device of claim 13, wherein the retaining ring includes a second coupling element for mechanically coupling the retaining ring to a circuit board of the encoder unit.
15. The retaining device of claim 14, wherein the retaining ring is made of conductive material to enable a grounding of the circuit board without installation of a separate grounding bracket, when the circuit board is directly screwed to the retaining ring.
16. The retaining device of claim 14, wherein the second coupling element is embodied as a threaded hole, and further comprising a second fastening screw received in the threaded hole for effecting a mechanical fastening of the circuit board on the retaining ring and an electrical ground connection of the circuit board.
17. The retaining device of claim 13, wherein the shielding element Is configured to shield a Wiegand sensor on the encoder unit against the external interference field.
18. The retaining device of claim 13, wherein the shielding element is embodied as a segment-shaped tab or as a closed pot.
19. The retaining device of claim 13, wherein the end shield includes a dust protection wall configured to protect a code disk arranged in the end shield.
20. The retaining device of claim 19, wherein the dust protection wall has a semicircular configuration.
21. A rotary encoder, comprising a retaining device which includes an end shield having a guide groove, a retaining ring including a first coupling element for mechanically coupling the retaining ring to the end shield, said first coupling element being embodied as a hole, a first fastening screw received in the hole to mechanically fasten the retaining ring to the end shield, and a shielding element integrally formed on the retaining ring for shielding against an external interference field.
22. The rotary encoder of claim 21, constructed in the form of a modular rotary encoder which Includes a rotary encoder module received in the guide groove of the retaining device, a code disk arranged in the end shield, and a circuit board mechanically coupled to the retaining ring by a second coupling element of the retaining ring.
23. The rotary encoder of claim 22, wherein the second coupling element is embodied as a threaded hole, said retaining device Including a second fastening screw received in the threaded hole for effecting a mechanical fastening of the circuit board on the retaining ring and an electrical ground connection of the circuit board.
24. The rotary encoder of claim 22, further comprising a Wiegand sensor arranged on the rotary encoder module and shielded by the shielding element against the external interference field.
25. The rotary encoder of claim 22, wherein the end shield includes a dust protection wall configured to protect the code disk.
26. The rotary encoder of claim 25, wherein the dust protection wall has a semicircular configuration.
27. The rotary encoder of claim 21, wherein the shielding element is embodied as a segment-shaped tab or as a closed pot.
28. The rotary encoder of claim 22, wherein the end shield includes at least two of said guide groove, said encoder module including at least two guide tabs to cooperate with the at least two guide grooves in the end shield.
29. The rotary encoder of claim 28, wherein the tabs are arranged on an upper end of the encoder module.
30. An electric machine, comprising a retaining device as set forth in claim 13 or a rotary encoder Including said retaining device.
31. A method for mounting a rotary encoder, in particular a modular rotary encoder, said method comprising: pressing a code disk of the rotary encoder onto an encoder bearing shaft of an encoder bearing arrangement; sliding in an encoder module by guiding tabs of the encoder module in guide grooves of an end shield of a retaining device; inserting the encoder module into a centering shoulder formed by an opening in the end shield placing a retaining ring of the retaining device onto the end shield; mounting the retaining ring on the end shield via a first fastening screw; mounting a circuit board including a connecting line on the retaining ring via a second fastening screw to produce an encoder unit; and mounting the encoder unit on an electric machine.
Description
[0032] In the drawings:
[0033] FIG. 1 shows a modular rotary encoder having a retaining device that is formed essentially from a retaining ring and an end shield,
[0034] FIG. 2 shows an encoder module for the modular rotary encoder that is illustrated in FIG. 1,
[0035] FIG. 3 shows a retaining ring for the modular rotary encoder that is illustrated in FIG. 1,
[0036] FIG. 4 shows an end shield for the modular rotary encoder that is illustrated in FIG. 1 and
[0037] FIG. 5 shows a lateral section through an electric machine having a modular rotary encoder.
[0038] FIG. 1 illustrates a modular rotary encoder 1 having a retaining device that is formed from a retaining ring 3 and an end shield 4. The retaining ring 3 is mechanically coupled to the end shield 4 mechanically via first fastening screws 18 and said retaining ring is then further illustrated and explained in conjunction with FIG. 3. The retaining ring 3 essentially includes a circular annular element 21 (cf. FIG. 3) and shielding tabs 6 are arranged on said annular element. Furthermore first coupling elements 16 are provided on the annular element 21 of the retaining ring 3 and said first coupling elements have fastening holes 7. These first coupling elements 16 are integrally formed on the annular element 21 in a lug-shaped manner. The fastening holes 7 (cf. FIG. 3) are used to feed through the first fastening screws 18 for coupling the retaining ring 3 in a mechanical manner to the end shield 4.
[0039] The rotary encoder 1 that is illustrated in FIG. 1 furthermore contains an encoder unit 5 that is mechanically mounted in the end shield 4 (cf. FIG. 4) and is additionally mechanically held by the retaining ring 3. Furthermore, second coupling elements 17 are arranged on the retaining ring 3 and threaded holes 8 are provided in said coupling elements so as to receive a circuit board 2, wherein the circuit board 2 is mechanically fastened by means of second fastening screws 19 in the first threaded holes 8 of the retaining ring 3 (cf. FIG. 3). The encoder unit 5 supports a so-called Wiegand sensor 11 that is visible in the upper region, wherein a shielding of the Wiegand sensor 11 is ensured by means of the shielding tabs that are integrally formed on the retaining ring 3.
[0040] The distinctive feature of the modular rotary encoder that is Illustrated in FIG. 1 resides in the fact that the rotary encoder 1 can be assembled in a simple and reliable manner from few modular components, wherein owing to the specific modular construction the modular rotary encoder 1 renders possible a simple mounting and also a reliable operation of the rotary encoder 1. One distinctive feature of the modular rotary encoder resides in the fact that tabs 14 are arranged on the encoder unit 5 in the upper region on opposite lying sides (cf. FIG. 2) and said tabs cooperate with corresponding guide grooves 10 (cf. FIG. 4) of the end shield 4 and thereby ensure a stable bearing arrangement of the encoder unit 5 in the end shield 4. The circuit board 2 that is required for a coordinate conversion is also mechanically fastened in a simple and secure manner to the retaining ring 3 of the rotary encoder 1 in the case of the rotary encoder 1 that is illustrated in FIG. 1, wherein moreover an electrical ground connection is also insured via the screw connections 19. Additional ground lines that are susceptible to Interference can therefore be omitted.
[0041] The distinctive feature of the rotary encoder 1 that is illustrated in FIG. 1 consequently resides in the fact that in contrast to previous solutions the assembly of the rotary encoder 1 is to be performed in a particularly simple manner. The specific design of the end shield 4 (cf. FIG. 2) having the lateral grooves 10 therefore allows the encoder unit 5, which is also referred to as a so-called C module, to slide particularly easily into the correct position wherein an incorrect mounting is thereby practically impossible. The end shield 4 furthermore has a dust protection wall 9 that lies on the side opposite the insertion (cf. FIG. 4) and said dust protection wall protects the code disk 12 (cf. FIG. 2) of the encoder unit 5 against contamination. The retaining ring 3 also simultaneously integrates multiple functions, namely said retaining ring on the one hand clamps the encoder unit 5 and holds the circuit board 2 and further shields the Wiegand sensor 11 by means of the shielding tabs 6. It is consequently possible owing to the dust protection wall 9 of the end shield 4 to omit a separate dust protection cap that would otherwise be required. As already stated, the circuit board 2 is directly grounded via the screwing arrangement to the retaining ring 3. It is possible by producing the retaining ring 3 from a conductive material, in particular from steel, for a separate grounding bracket to no longer be necessary as would be required in the case of dust protection caps or fastening apparatuses that are embodied previously from plastic.
[0042] As already stated, the retaining ring consequently integrates the functions of “clamping the encoder, holding and grounding the circuit board and also shielding the Wiegand sensor”. Altogether, this consequently reduces assembly costs and also leads to an increase in quality during assembly as well as during operation and furthermore also leads to it being easy to repair during maintenance work.
[0043] The mounting of the modular rotary encoder on a motor end shield 26 of an electric machine 25 (cf. FIG. 5) is consequently performed essentially in the following steps: [0044] mounting the encoder bearing arrangement: constructing the encoder bearing arrangement comprised of an end shield, an encoder bearing shaft having two ball bearings and an engagement spring and also a coupling half. [0045] pressing the code disk: for this purpose the code disk 12 is pressed onto the encoder bearing shaft of the electric machine 25. [0046] sliding the encoder module 13 in: in this case the tabs 14 are used as a guiding arrangement in the grooves 10 of the end shield 4. [0047] inserting the encoder module 13 into the centering shoulder that is formed by an opening 24 in the end shield 4. [0048] placing the retaining ring 3 onto the end shield 4 and mounting the retaining ring 3 on the end shield 4 by means of the first fastening screws. [0049] placing the circuit board 2 on the retaining ring 3 and fastening the circuit board 2 to the retaining ring 3 by means of the second fastening screws. [0050] mounting the circuit board including the connecting line on the retaining ring by means of the fastening screws. [0051] mounting the complete encoder unit 1 on the electric machine 25.
[0052] FIG. 2 illustrates an encoder module 5 for the modular rotary encoder 1 that is Illustrated in FIG. 1. FIG. 2 again illustrates which components are essentially comprised in the encoder unit 5. The encoder unit 5 essentially comprises an opening 15 for the encoder module 13 having the code disk 12. The encoder unit 5 has a cylindrical sidewall 22 that is provided with tabs 14 on in each case two opposite lying sides. These tabs 14 correspond to guide grooves 10 as they are provided in FIG. 4 on the end shield 4. The tabs 14 are consequently used to guide and orient the angular position. Furthermore, the Wiegand sensor 11, as has already been explained in conjunction with FIG. 1, is also apparent in FIG. 2. With regard to the operating principle and the cooperation of the encoder unit 5 in relation to the modular rotary encoder 1 reference is made to the statements with regard to FIG. 1 and also the remaining figures.
[0053] FIG. 3 illustrates a retaining ring 3 for the modular rotary encoder 1 that is Illustrated in FIG. 1. The retaining ring 3 essentially includes an annular element 21 and shielding tabs 6 are integrally formed on said annular element. Furthermore, the retaining ring 3 has first coupling elements 16 and also second coupling elements 17, the first coupling elements 16 are embodied as lugs 16 that are integrally formed on the annular element 21 and fastening holes 7 are Integrated into said lugs so as to receive first fastening screws for the end shield (cf. FIG. 1). The second coupling elements 17 are embodied as second lugs 17 that are integrally formed on the annular element 21 and said second lugs have first threaded holes 8 for receiving second fastening screws 19 for the circuit board (cf. FIG. 1).
[0054] The second lug elements 17 are embodied further spaced with respect to the first lug elements 16 from the annular element 21 and the thickness of these lug elements 17 is embodied as thicker in the region of the threaded holes 8 in order to ensure a secure seat of the fastening screws 19 for the circuit board 2.
[0055] Finally, FIG. 4 illustrates an end shield 4 for the modular rotary encoder 1 that is illustrated in FIG. 1. The distinctive feature of the end shield 4 that is illustrated in FIG. 4 resides in the fact that a semicircular band element 23 is provided on the end shield 4 and said band element has in each case guide grooves 10 on opposite lying sides and said guide grooves are provided so as to receive the guide tabs 14 that are arranged on the encoder unit 5. The front semicircle of the end shield 4 between the wall elements 23 is embodied as open in a first semicircular region with the result that it is rendered possible to insert the encoder unit 5 while the opposite lying region of the end shield 4 supports a dust protection wall 9 that is used as dust protection for the encoder module or the entire encoder unit 5 and in particular the code disk 12.
[0056] FIG. 5 illustrates a lateral section through an electric machine 25 having a modular rotary encoder. The figure serves in particular to clarify where and how the modular rotary encoder is coupled to a motor end shield 26 of the electric machine via the end shield 4 of the rotary encoder.
[0057] In summary, the invention consequently relates to a retaining device 3, 4 for coupling an encoder unit 5 of an in particular modular rotary encoder 1 to a motor end shield 26 of an electric machine 25. For a simple and secure mounting in particular of a modular rotary encoder and also for its reliable operation, it is proposed that the retaining device 3, 4 is essentially formed from a retaining ring 3 and an end shield 4 of the rotary encoder 1, wherein the retaining ring 3 has first coupling elements 16 for mechanically coupling the retaining ring 3 to the end shield 4 and wherein the end shield 4 has guide grooves 10 for receiving an encoder module 13 of the encoder unit 5, wherein the first coupling elements (16) that are provided in the retaining ring 3 are embodied as holes (7) for receiving first fastening screws (18) for mechanically fastening the retaining ring (3) to the end shield (4) and wherein at least one shielding element (6) for shielding against external interference fields is integrally formed on the retaining ring (3). The second coupling element (17) is embodied as a threaded hole (8) for receiving and grounding the circuit board (2) via the second fastening screws (19).
