Resolver

Abstract

The invention relates to a resolver (4) comprising two units (1, 2) which can be rotated relative to each other about an axis (A), the resolver (4) being suitable for determining a relative angular position between the two units (1, 2). At least one of the two units (1, 2) has a plurality of resolver windings (1.1, 2.1) and transformer windings (1.4, 2.4). The first unit (1) comprises a first housing element (1A) and a second housing element (2B). The second unit (2) comprises a first sleeve element (2A) and a second sleeve element (2B). The first housing element and the second housing element (1A, 1B) are coupled to each other at at least one connection point (3.1) extending in the circumferential direction. In addition or alternatively, the first and second sleeve elements (2A, 2B) are also coupled at at least one further connection point (3.2) extending in the circumferential direction.

Description

Technical Field

[0001] The invention relates to a resolver having a modular structure according to claim 1 .

[0002] In electrical engineering, a resolver is an electromagnetic measuring transducer that converts the angular position of a rotor into an electrical quantity or an electrical signal. In this application, the term resolver also includes measuring transducers known as synchros or resolvers or RVDTs (rotary variable differential transformers).

[0003] In a brushless resolver, a plurality of windings are usually arranged in a housing. These windings include, on the one hand, a resolver winding consisting of a stator winding and a rotor winding, and, on the other hand, a transformer winding arranged on the rotor and the stator. In order to minimize undesired magnetic flux between the resolver winding and the transformer winding, the resolver winding is located in a first distal region of the resolver, while the transformer winding is located as far as possible in a second distal region opposite the resolver.

[0004] Such resolvers are usually produced in large quantities, so that simple and, if possible, fully automated production is desirable. Background Art

[0005] From publication EP1667313 A1, a resolver is known which comprises a one-piece rotor sleeve and a multi-part stator housing, wherein the rotor sleeve and the stator housing are made of the same material. Magnetic interferences between the resolver windings and the transformer windings are minimized via additional shielding structures.

[0006] Such a design has disadvantages with regard to measuring accuracy and can only be produced or assembled with relatively high complexity. Summary of the invention

[0007] The object of the present invention is to provide a resolver which has a relatively high measurement accuracy and can be mass-produced in a relatively ideal manner.

[0008] This object is achieved by the features of claim 1. Advantageous refinements and developments are given in the respective dependent claims.

[0009] The resolver according to the invention comprises two structural units that can rotate relative to each other around an axis, wherein the resolver is suitable for determining the relative angular position between the two structural units. At least one of the structural units has a plurality of resolver windings and transformer windings. The first structural unit comprises a first housing element and a second housing element. The second structural unit comprises a first sleeve element and a second sleeve element. The first housing element and the second housing element are coupled or connected to each other at at least one connection position, which extends along the circumference of the first housing element and the second housing element. In addition or alternatively, the first sleeve element and the second sleeve element are coupled to each other at at least one other connection position, which extends along the circumference of the first sleeve element and the second sleeve element.

[0010] The coupling between the first housing element and the second housing element or between the first sleeve element and the second sleeve element prevents an axial displacement, in particular of the mutually coupled elements. For this purpose, a relative axial displacement of the first housing element with respect to the second housing element or a relative axial displacement of the first sleeve element with respect to the second sleeve element should be prevented.

[0011] In a further embodiment, the first housing element and, in addition or as an alternative, the first sleeve element are made of a first material. Furthermore, the second housing element and, in addition or as an alternative, the second sleeve element are made of a second material.

[0012] Preferably, the first material is a non-magnetic material and the second material is a magnetic material.

[0013] In this case, the magnetic material or magnetic substance refers in particular to a ferromagnetic material which has a high magnetic permeability and a low remanence.

[0014] Non-magnetic material or non-magnetic substance refers to non-ferromagnetic material, which is essentially non-magnetizable, that is, has low magnetic permeability and high remanence.

[0015] According to a preferred improvement of the present invention, the coupling between the first housing element and the second housing element is anti-twist or anti-torsion. In addition or alternatively, the coupling between the first sleeve element and the second sleeve element is also anti-twist or anti-torsion, or only the coupling between the first sleeve element and the second sleeve element is anti-twist or anti-torsion.

[0016] Preferably, the coupling between the first housing element and the second housing element is formed by a connection technique of form fit, force fit and supplementary or alternative material fit. Additionally or alternatively, the coupling between the first and second sleeve elements is also formed by a connection technique of form fit, force fit and supplementary or alternative material fit, or only the coupling between the first and second sleeve elements is formed by a connection technique of form fit, force fit and supplementary or alternative material fit.

[0017] Preferably, at least the first sleeve element and the second sleeve element are designed to be rotationally symmetrical.

[0018] According to an advantageous development of the invention, the transformer winding is arranged in the region of the second housing element and the second sleeve element, and the resolver winding is arranged in the region of the first housing element and the first sleeve element.

[0019] In the area of ​​the first housing element and the first sleeve element, the arrangement of the resolver winding on the structural unit itself or the arrangement of the resolver winding in the cavity formed by one or more of these components is understood. Similarly, in the area of ​​the second housing element and the second sleeve element, the arrangement of the transformer winding on the structural unit itself or the arrangement of the transformer winding in the cavity formed by these components is understood.

[0020] In a further embodiment, the housing element and the sleeve element are designed and arranged to form an air gap between the structural units, and at least the resolver winding and the transformer winding are shielded from all sides by the housing element and the sleeve element.

[0021] According to another aspect, the present invention includes a resolver series. Thus, each resolver is modular in structure and includes two structural units that can rotate relative to each other around an axis. Each resolver of the series is used to determine the relative angular position of its two structural units during operation. At least one of the two structural units always has a plurality of resolver windings and transformer windings. The first structural unit always includes a first housing element and a second housing element. The second structural unit always includes a first sleeve element and a second sleeve element. The first housing element and the second housing element are coupled to each other at at least one connection position, which extends along the circumference of the first housing element and the second housing element. In addition, the first sleeve element and the second sleeve element can also be coupled to each other at at least one other connection position, which extends along the circumference of the first sleeve element and the second sleeve element.

[0022] The resolvers in this series are assembled according to a modular design principle, wherein the components are selected from a number of different embodiments as required.

[0023] Further advantageous embodiments of the invention are given in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The figure shows:

[0025] Figure 1 A longitudinal section of the decomposer. DETAILED DESCRIPTION

[0026] The present invention will further explain its features and advantages based on the description of the embodiments in conjunction with the schematic illustrations of the accompanying drawings.

[0027] The invention is based on the recognition that so-called "crosstalk" occurs in brushless resolvers in which the transformer winding and the resolver winding are arranged directly adjacent to each other in the resolver housing. In this case, the electromagnetic field of the transformer winding acts on the resolver winding as a disturbance factor, resulting in a decrease in measurement accuracy. The invention achieves simplified manufacturing and decoupling or shielding of the resolver winding by the transformer magnetic field by selecting suitable materials and designing the structure of the housing elements and sleeve elements of the stator and rotor, thereby reducing crosstalk.

[0028] according to Figure 1 The modularly designed resolver 4 includes two structural units that can rotate around an axis A, namely a stator 1 as a first structural unit and a rotor 2 as a second structural unit. An air gap L is formed between the stator 1 and the rotor 2. The stator 1 has a first housing element 1A and a second housing element 1B, which are coupled to each other to prevent relative axial displacement and torsion. The first housing element 1A includes a receiving portion suitable for a laminated core 1.2. A resolver winding 1.1, for example, a resolver winding made of copper wire, is arranged on the laminated core 1.2 as a receiving coil. In addition, the stator 1 has a transformer winding 1.4, which is arranged in the area of ​​the second housing element 1B.

[0029] By means of a corresponding resolver 4, the relative angular position between the stator 1 and the rotor 2 can be determined. For this purpose, a sinusoidal alternating current is applied to the transformer winding 1.4 of the stator 1, which induces an alternating voltage with a predetermined transformation ratio in the transformer winding 2.4 of the rotor 2. This alternating voltage is therefore also applied to the resolver winding 2.1 of the rotor, so that a corresponding output voltage is induced in the resolver winding 1.1 of the stator 1 surrounding the resolver winding 2.1 of the rotor 2. When two resolver windings 1.1 of the stator 1 are used, which are 90° out of phase, two voltage signals with a 90° phase difference can be obtained, which depend on the relative angular position between the stator 1 and the rotor 2. Therefore, the current resolver 4 is implemented as a brushless or slip ring-free resolver.

[0030] Figure 1 Electrical inputs and outputs (not shown) from the resolver winding 1.1 and the transformer winding 1.4 are led outward from the interior of the first and second housing elements 1A, 1B through holes or guide sleeves 5 which are partially arranged in the holes.

[0031] The rotor 2 has a first sleeve element 2A and a second sleeve element 2B, which are also coupled to each other to prevent relative axial displacement and rotation. In the embodiment shown, the first and second sleeve elements 2A, 2B are coupled to a hollow shaft, which can be fixed in a torsion-proof manner to a motor shaft (not shown), for example, to determine its angular position. The first sleeve element 2A includes a receptacle for arranging a laminated core 2.2, where a resolver winding 2.1 is arranged. In addition, the rotor 2 has a transformer winding 2.4, which is arranged in the area of ​​the second sleeve element 2B. Usually, the resolver winding 2.1 is encapsulated together with the laminated core 2.2. For the sake of simplicity, the encapsulation material is not shown. Figure 1 Displayed in.

[0032] In addition to the laminated core 1.2 and the laminated core 2.2, other alternative components can also be used which facilitate the focusing of the electromagnetic waves.

[0033] For example, the coupling between the first housing element 1A and the second housing element 1B or the first sleeve element 2A and the second sleeve element 2B is achieved by a connection technique such as a form fit and a force fit. Preferably, a material fit connection technique is used when coupling the housing elements 1A, 1B or when coupling the sleeve elements 2A, 2B, such as by laser welding or by bonding.

[0034] Figure 1 The resolver 4 shown is a resolver with a modular structure, i.e. it can be assembled and manufactured according to the modular principle. Almost every component of the resolver 4 has different implementations, wherein the components of all implementations do not exceed the predefined installation space and meet other standards. For example, the resolver windings 1.1, 1.2 can include implementations with different winding patterns.

[0035] By selectively selecting the embodiment of the individual components, advantageous synergistic effects can also be achieved. It is therefore particularly advantageous if the first housing element 1A and the second housing element 1B are made of different materials and the first sleeve element 2A and the second sleeve element 2B are made of different materials. In this way, the distribution of the magnetic flux emitted by the energized transformer windings 1.4 and 2.4 within the resolver 4 can be selectively influenced.

[0036] exist Figure 1 In the embodiment shown, the first housing element 1A and the first sleeve element 2A are made of the same non-magnetic material, ie, not a magnetic material. Suitable materials for this are, for example, non-magnetic steel, aluminum, aluminum alloys or plastics.

[0037] The second housing element 1B and the second sleeve element 2B are made of the same magnetic material. A suitable material for this is, for example, magnetic steel.

[0038] By this design, the transformer magnetic field is mainly retained in the area of ​​the transformer windings 1.4, 2.4, because it is preferentially coupled to the magnetic second housing element 1B and the magnetic second sleeve element 2B. The non-magnetic first housing element 1A and the non-magnetic first sleeve element 2A hardly or completely conduct the magnetic flux of the transformer magnetic field, thereby magnetically decoupling this part of the resolver 4 from the resolver windings 1.1, 1.2. In this way, it is possible to save additional shielding elements between the transformer windings 1.4, 2.4 and the resolver windings 1.1, 2.1.

[0039] The housing elements 1A, 1B and the sleeve elements 2A, 2B shield the resolver windings 1.1, 2.1 and the transformer windings 1.4, 2.4, thereby protecting the interior of the resolver 4 from contamination from all sides.

[0040] In the proposed embodiment, the housing elements 1A, 1B and the sleeve elements 2A, 2B are designed to be rotationally symmetrical and have approximately the same longitudinal extension in the axial direction relative to the axis A. This allows these components to use semi-finished products or blanks, wherein the final product is manufactured by forming component-specific features during final processing. In this way, the first housing element 1A or the second housing element 1B can be manufactured from the corresponding semi-finished product.

[0041] Alternatively, the first housing element 1A and the first sleeve element 2A can be made of non-magnetic material, while the second housing element 1B and the second sleeve element 2B can be made of magnetic material. In this case, the resolver windings 1.1, 2.1 are mainly protected from external magnetic field interference. In this alternative embodiment, the external interference magnetic field will be coupled into the second housing element 1B and the second sleeve element 2B, and the magnetic flux will remain therein.

[0042] Another advantage is that the resolvers can be manufactured and assembled in a standardized manner in one series, even if the individual components of the finished resolvers are not identical.

Claims

1. A modularly constructed resolver (4), comprising two structural units (1, 2) which are rotatable relative to each other about an axis (A), wherein: The resolver (4) is suitable for determining the relative angular position between the two structural units (1, 2), and at least one of the two structural units (1, 2) has a resolver winding (1.1, 2.1) and a transformer winding (1.4, 2.4), The first structural unit (1) comprises a first shell element (1A) and a second shell element (1B). The second structural unit (2) comprises a first sleeve element (2A) and a second sleeve element (2B). The first housing element and the second housing element (1A, 1B) are coupled at at least one circumferentially extending connection position (3.1) and / or the first sleeve element and the second sleeve element (2A, 2B) are coupled at at least one further circumferentially extending connection position (3.2).

2. The decomposer according to claim 1, wherein: The first housing element (1A) and / or the first sleeve element (2A) are made of a first material, and the second housing element (1B) and / or the second sleeve element (2B) are made of a second material.

3. The decomposer according to claim 2, wherein: The first material is a non-magnetic material, and the second material is a magnetic material.

4. The decomposer according to at least one of the preceding claims, wherein The coupling between the first housing element and the second housing element (1A, 1B) is designed to be rotationally fixed, and / or The coupling between the first sleeve element and the second sleeve element (2A, 2B) is designed to be rotationally fixed.

5. The decomposer according to at least one of the preceding claims, wherein The coupling between the first housing element and the second housing element (1A, 1B) is designed to be form-fitting, force-fitting and / or material-fitting, and / or The coupling between the first sleeve element and the second sleeve element (2A, 2B) is designed to be form-fitting, force-fitting and / or material-fitting.

6. The decomposer according to at least one of the preceding claims, wherein At least the first sleeve element and the second sleeve element (2A, 2B) are designed to be rotationally symmetrical.

7. The decomposer according to at least one of the preceding claims, wherein The transformer winding (1.4, 2.4) is arranged in the region of the second housing element (1B) and the second sleeve element (2B), and the resolver winding (1.1, 2.1) is arranged in the region of the first housing element (1A) and the first sleeve element (2A).

8. The decomposer according to at least one of the preceding claims, wherein The housing element (1A, 1B) and the sleeve element (2A, 2B) are designed and arranged so that an air gap (L) is formed between the structural units (1, 2) and at least the resolver winding and the transformer winding are shielded from all sides by the housing element (1A, 1B) and the sleeve element (2A, 2B).

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