Harmonic drive, and flanged bushing for a harmonic drive having a sensor device

Abstract

The invention relates to a flanged bushing (1) for a harmonic drive (2), having a sensor device for measuring a temperature, a pressure, a voltage, a magnetic field and / or a linear position on the flanged bushing (1), comprising • at least one bistable magnetic wire (3) arranged in the region of a surface of the flanged bushing (1), • at least one excitation element (4) for generating a magnetic field, wherein the at least one excitation element (4) is arranged outside the flanged bushing (1) in the range of the at least one bistable magnetic wire (3), • at least one sensor element (5) for receiving a reaction of the at least one bistable magnetic wire (3), wherein the at least one sensor element (5) is arranged outside the flanged bushing (1) in the range of the at least one bistable magnetic wire (3), and • a signal processing unit (6), which is arranged outside the flanged bushing (1) and is signal-transmittingly connected to the at least one excitation element (4) and the at least one sensor element (5) and is designed to generate and receive electrical signals. The invention also relates to a harmonic drive (2) having such a flanged bushing (1).

Description

[0001] Corrugated gear and claw sleeve for a corrugated gear with a sensor device

[0002] The invention relates to a collar sleeve for a wave gear with a sensor device for measuring temperature, pressure, voltage, magnetic field and / or linear position. The invention further relates to a wave gear with such a collar sleeve.

[0003] For example, DE 10 2019 134 661 A1 discloses a wave gear with a drive wheel, a collar sleeve which is connected to the drive wheel and has a sleeve-shaped section with external teeth and a radially outwardly directed flange, a wave generator which interacts with the collar sleeve and has a flexible outer ring, and an internally toothed output wheel.

[0004] Furthermore, EP 4 257 929 A1 discloses a system for measuring a physical quantity and / or a position. The system comprises a bistable magnet wire, an excitation element for generating a magnetic field within whose range the bistable magnet wire is arranged, wherein the bistable magnet wire is provided for magnetization reversal by a Barkhausen jump from a first end to a second end or vice versa, and a sensor element for receiving the response of the bistable magnet wire. The excitation element and the bistable magnet wire are arranged in such a position that the amplitude of the magnetic field excited by the excitation element at the first end differs from the amplitude of the magnetic field excited by the excitation element at the second end.

[0005] The object of the invention is to improve a collar sleeve for a wave gear. In particular, physical quantities and / or a position on the collar sleeve should be able to be precisely detected by a sensor device. Furthermore, the sensor device should be cost-effective and robust. These objects are achieved by the subject matter of claim 1. Preferred embodiments can be found in the dependent claims, the description, and the figures. A collar sleeve for a wave gear according to the invention comprises a sensor device for measuring a temperature, a pressure, a voltage, a magnetic field, and / or a linear position on the collar sleeve, wherein the sensor device has the following: at least one bistable magnet wire arranged in the region of a surface of the collar sleeve, at least one excitation element for generating a magnetic field,wherein the at least one excitation element is arranged within range of the at least one bistable magnet wire outside the collar sleeve, at least one sensor element for receiving a response from the at least one bistable magnet wire, wherein the at least one sensor element is arranged within range of the at least one bistable magnet wire outside the collar sleeve, and a signal processing unit, which is arranged outside the collar sleeve, is connected to the at least one excitation element and the at least one sensor element for signal transmission and is configured to generate and receive electrical signals.

[0006] The at least one bistable magnetic wire is made of a magnetizable material and forms a passive sensor, generating signals through magnetic induction. These signals are altered by environmental influences, enabling the measurement of at least temperature, pressure, voltage, magnetic field, and / or linear position. In particular, the at least one bistable magnetic wire is encased in a layer of insulating material, such as glass. This not only makes the bistable magnetic wire more robust but also increases its durability. The excitation element preferably comprises an excitation coil configured to remagnetize the at least one bistable magnetic wire. The sensor element preferably comprises a sensor coil configured to receive responses from the at least one bistable magnetic wire.In particular, the sensor coil of the sensor element is separate from the excitation coil of the excitation element. For example, the excitation element and the sensor element are arranged in a common housing and connected to the signal processing unit via a cable. For example, a large number of bistable magnet wires, in particular up to one hundred magnet wires, can be excited by a single excitation element and read out via a single sensor element. Depending on the measured data acquired at the collar sleeve, the wave gear, in particular the wave generator or an associated drive motor, can be controlled very precisely. The direct measured quantities acquired by the sensor device at the collar sleeve are mechanical stress, temperature, and a magnetic field. Indirectly, pressures, torques, bends, and positions, for example, can be determined from these measured quantities.

[0007] In particular, the at least one bistable magnet wire is provided for magnetization reversal by a Barkhausen jump from a first end to a second end or vice versa, wherein the at least one excitation element and the at least one bistable magnet wire are positioned such that the amplitude of the magnetic field excited by the at least one excitation element at the first end differs from the amplitude of the magnetic field excited by the at least one excitation element at the second end.

[0008] According to one embodiment, bistable magnetic wires of varying lengths, diameters, and / or orientations are arranged on the surface of the collar sleeve. The length, diameter, and orientation of each magnetic wire influence its magnetizability and thus its response to changes in its environment. In particular, this allows the sensitivity and response to be tailored to the specific application.

[0009] According to one embodiment, the at least one bistable magnet wire is glued to the end face of the collar sleeve. Alternatively or additionally, the at least one bistable magnet wire is glued at least partially to a cylindrical section of the collar sleeve. For example, the at least one bistable magnet wire extends at least partially along the end face and at least partially along a cylindrical section of the collar sleeve. For example, several bistable magnet wires are glued to different locations on the collar sleeve and thus firmly bonded to its surface. Preferably, the bistable magnet wires are first applied to a carrier film, the carrier film and the bistable magnet wires forming a semi-finished product that is precisely positioned on the collar sleeve so that the positioning of the bistable magnet wires relative to each other is reproducible.In particular, the bistable magnetic wires are bonded to the collar sleeve at points where the greatest deformation and stress occur during operation of the wave gear. Preferably, the at least one bistable magnetic wire is coated with a protective layer. This protective layer is particularly flexible and durable, providing additional protection and fixation to the surface of the collar sleeve.

[0010] According to one embodiment, the signal processing unit is configured to be located outside the wave gear. Preferably, the at least one excitation element and the at least one sensor element are configured to be fixed to a stationary component of the wave gear located adjacent to the collar sleeve. For example, the stationary component is designed as the housing of the wave gear or as a component non-rotatably connected to it. In particular, the signal processing unit can be arranged outside the wave gear on the housing and connected to the at least one excitation element and the at least one sensor element via cables.

[0011] According to one embodiment, a single excitation element and a single sensor element are arranged continuously in the vicinity of the collar sleeve. Alternatively, several excitation elements and several sensor elements are arranged in the vicinity of the collar sleeve.

[0012] The invention also relates to a wave gear with a collar sleeve according to the invention. The wave gear comprises a flexible ring element, designed as a collar sleeve and having external teeth, which is continuously deformable in the radial direction by a wave generator, and a ring gear designed as a rigid ring element with internal teeth. The external teeth of the flexible ring element mesh with the internal teeth of the ring gear at at least one tooth engagement area to transmit a torque. The wave generator has a non-circular bearing element comprising an inner ring, an outer ring, and rolling elements arranged between them. The bearing element projects axially, at least partially, into the flexible ring element, with the inner ring being rotationally fixed to the gear input shaft.The flexible ring element, also called a flexspline, is a high-strength and torsionally rigid collar sleeve that is fixed to the housing, for example, by being bolted to it. The flexible ring element is designed to accommodate the shaft generator and bearing element, at least partially axially, and is locally deformable depending on the shaft generator's outer shape. In particular, the shaft generator's outer shape is determined by the inner ring and formed on the outer ring. The rolling elements of the bearing element contact the outer circumferential surface of the inner ring, with a first raceway for the rolling elements formed on the outer circumferential surface of the inner ring. Furthermore, the rolling elements of the bearing element contact the inner circumferential surface of the outer ring, with a second raceway for the rolling elements formed on the inner circumferential surface of the outer ring.Preferably, the rolling elements are guided in a cage, the cage being preferably made of a polymer material to reduce wear on the rolling elements. The flexible ring element has at least one open axial side for receiving the shaft generator with the bearing element, wherein the inner circumferential surface of the flexible ring element is configured to receive the outer circumferential surface of the outer ring of the bearing element during operation of the shaft generator.

[0013] During operation of the wave gear, the wave generator rotates, causing the inner ring of the bearing element to twist relative to the flexible ring element and the outer ring of the bearing element housed within it. The flexible ring element deforms elastically in accordance with the direction and speed of rotation of the wave generator. Thus, the wave generator is set into a rotational motion during operation of the wave gear, which causes the flexible ring element to undergo circumferential deformation. Preferably, the external teeth of the flexible ring element, which transmit torque, engage at least partially with the internal teeth of the ring gear in two symmetrically opposed tooth engagement areas relative to the axis of rotation of the wave generator. This allows for uniform force application and transmission, and enables a space-saving design of the wave gear.

[0014] The ring gear, also called a circular spline, is a torsionally rigid ring whose internal teeth have more teeth than the external teeth of the flexible ring element. The rotation of the shaft generator causes a continuous, circular meshing of the teeth between the flexible ring element and the ring gear. In other words, the opposing tooth meshing areas move continuously around the axis of rotation of the shaft generator, i.e., in the circumferential direction, as the shaft generator rotates. Since the flexible ring element has fewer teeth than the ring gear, rotation of the shaft generator causes a relative movement of the flexible ring element to the ring gear. This results in the rolling elements of the bearing element rolling between the inner and outer rings.

[0015] Further measures improving the invention are described in more detail below, together with a description of preferred embodiments of the invention, with reference to the figures.

[0016] Figure 1 is a highly simplified schematic representation of a wave gear, only partially shown, with a collar sleeve according to the invention.

[0017] Figure 2 shows a highly simplified schematic representation of the collar sleeve according to a second embodiment of the invention and

[0018] Figure 3 shows a highly simplified schematic representation of the collar sleeve according to a third embodiment of the invention.

[0019] Figure 1 shows a section of a wave gear 2, where only a collar sleeve 1, a wave generator 10 interacting with the collar sleeve, and a stationary component 8 designed as a housing are shown in a highly simplified manner. The collar sleeve 1 has a sensor device for measuring temperature, pressure, voltage, a magnetic field, and / or a linear position on the collar sleeve 1. The sensor device comprises several bistable magnetic wires 3 arranged in the region of a surface of the collar sleeve 1, an excitation element 4 for generating a magnetic field, a sensor element 5 for receiving a response from the bistable magnetic wires 3, and a signal processing unit 6, which is connected to the excitation element 4 and the sensor element 5 via cables (not shown) and is configured to generate and receive electrical signals.The excitation element 4 and the sensor element 5 are arranged around a rotational axis 9 and within reach of the bistable magnetic wires 3 outside the collar sleeve 1. The signal processing unit 6 is located outside the wave gear 2. In this configuration, the excitation element 4 and the sensor element 5 are arranged on an inner side of the stationary component 8, and the signal processing unit 6 is arranged on an outer side of the stationary component 8. Alternatively, the excitation element 4, the sensor element 5, and the signal processing unit 6 can be arranged on a common side of the stationary component 8.

[0020] The collar sleeve 2 is fixed in a stationary position and thus prevented from rotating about the axis of rotation 9 during operation of the wave generator 10. The collar sleeve 2 deforms elastically during operation of the wave generator 10, thereby introducing stresses and heat into the collar sleeve 2. Several bistable magnetic wires 3 of different lengths, diameters, and orientations are arranged on the surface of the collar sleeve 1. The bistable magnetic wires 3 are at least partially bonded to an end face of the collar sleeve 1, to a cylindrical section of the collar sleeve 1, and to an intermediate area. The bistable magnetic wires 3 arranged on the end face are coated with a protective layer 7.

[0021] Figure 2 shows an alternative embodiment of the collar sleeve 1. In this embodiment, several identically designed bistable magnetic wires 3 are arranged evenly distributed on the end face of the collar sleeve 1. A single excitation element 4 and a single sensor element 5, both extending around the axis of rotation 9, are arranged in the vicinity of the collar sleeve 1 and are configured to excite and read the bistable magnetic wires 3.

[0022] Figure 3 shows another embodiment of the collar sleeve 1. In this embodiment, several bistable magnetic wires 3 of different lengths, diameters, and orientations are arranged on the end face of the collar sleeve 1. Furthermore, several excitation elements 4 and several sensor elements 5 are arranged in the vicinity of the collar sleeve 1 and within reach of the respective bistable magnetic wires 3, and are configured to excite and read the bistable magnetic wires 3. The excitation elements 4 and sensor elements 5 are connected via cable to a single signal processing unit (not shown in detail) for data processing.

[0023] List of reference signs

[0024] 1 collar sleeve

[0025] 2 wave gears 3 bistable magnet wire

[0026] 4. Stimulus element

[0027] 5 sensor element

[0028] 6 Signal processing unit

[0029] 7 Protective layer 8 Stationary component

[0030] 9. Axis of rotation

[0031] 10-wave generator

Claims

Patent claims 1. Collar sleeve (1) for a wave gear (2) comprising a sensor device for measuring a temperature, a pressure, a voltage, a magnetic field and / or a linear position on the collar sleeve (1). • at least one bistable magnet wire (3) arranged in the area of ​​a surface of the collar sleeve (1 ), • at least one excitation element (4) for generating a magnetic field, wherein the at least one excitation element (4) is arranged within reach of the at least one bistable magnet wire (3) outside the collar sleeve (1), • at least one sensor element (5) for receiving a response from the at least one bistable magnet wire (3), wherein the at least one sensor element (5) is arranged within range of the at least one bistable magnet wire (3) outside the collar sleeve (1), and • a signal processing unit (6) arranged outside the collar sleeve (1 ), connected to the at least one excitation element (4) and the at least one sensor element (5) for signal transmission and configured to generate and receive electrical signals.

2. Collar sleeve (1) according to claim 1, characterized in that bistable magnetic wires (3) with different lengths, different diameters and / or different orientations are arranged in the area of ​​the surface of the collar sleeve (1).

3. Collar sleeve (1 ) according to one of the preceding claims, characterized in that the at least one bistable magnet wire (3) is at least partially glued onto an end face of the collar sleeve (1 ).

4. Collar sleeve (1 ) according to one of the preceding claims, characterized in that the at least one bistable magnet wire (3) is at least partially glued onto a cylindrical section on the collar sleeve (1).

5. Collar sleeve (1 ) according to one of the preceding claims, characterized in that the at least one bistable magnet wire (3) is coated with a protective layer (7).

6. Collar sleeve (1 ) according to one of the preceding claims, characterized in that the signal processing unit (6) is arranged to be located outside the wave gear (2).

7. Collar sleeve (1 ) according to one of the preceding claims, characterized in that the at least one excitation element (4) and the at least one sensor element (5) are arranged to be fixed on a stationary component (8) of the wave gear (2) arranged adjacent to the collar sleeve (1 ).

8. Collar sleeve (1 ) according to one of the preceding claims, characterized in that a single excitation element (4) and a single sensor element (5) are arranged circumferentially in the vicinity of the collar sleeve (1 ).

9. Collar sleeve (1 ) according to one of the preceding claims, characterized in that several excitation elements (4) and several sensor elements (5) are arranged in the vicinity of the collar sleeve (1 ).

10. Wave gear (2) with a collar sleeve (1) according to one of the preceding claims.

Images