Metal bellows coupling

Abstract

Metal bellows coupling with at least two compensating elements arranged opposite each other, with at least one cylindrical hollow body arranged between the compensating elements, in particular in the form of at least one flange or in particular in the form of at least one tube, and with at least one sensor device or sensor assembly arranged inside the hollow body.

Description

Technical area

[0001] The invention relates to a generic metal bellows coupling. State of the art

[0002] Metal bellows couplings (see state of the art: Fig. 1) are used to transmit power in drivetrains. Power is determined by the operating speed and the operating torque.

[0003] Furthermore, the coupling serves to compensate for misalignments between one hub or shaft and the other, which is achieved through the bellows. Metal bellows couplings are particularly suitable for direct drives.

[0004] The typical metal bellows is the core of the coupling and compensates for lateral, axial, and / or angular hub or shaft misalignments with low restoring forces. Backlash-free, torsionally rigid metal bellows couplings guarantee precise positioning of the drive train, can ensure torque transmission from 2 Nm to 10,000 Nm, and can be used in highly dynamic applications up to 120,000 rpm.

[0005] To fully utilize their technical properties and compensate for hub or shaft misalignments without transmission errors, precise assembly of the metal bellows couplings is crucial. Factors such as operational reliability, acceleration torque, and resonance frequency are important when dimensioning.

[0006] The integration of sensors for measuring physical quantities, such as torque, is not possible here. Attachments can be glued, welded, or pressed onto the metal bellows.

[0007] Description of the present invention: Task, solution, advantages

[0008] Based on the disadvantages and deficiencies outlined above and taking into account the outlined prior art, the present invention is based on the object of developing a metal bellows coupling of the type mentioned at the outset in such a way that the disadvantages and deficiencies are overcome.

[0009] This object is achieved according to the invention in a generic metal bellows coupling as follows: The bellows corrugations, which serve as compensating elements, are placed at a greater distance from each other to create a cylindrical hollow body between them. One, two, or more bellows corrugations can be used on each side. Strain gauges can be applied to the cylinder's outer surface. The strain gauge cables can be routed through one or more holes in this surface. Alternatively, the strain gauges can also be applied to the inner surface of the outer surface.

[0010] The sensor metal bellows coupling can be designed as an inductive variant with a wire winding on the outer surface and pick-up (separate component) for the power supply of the electronics or as a battery variant in addition to the induction or without induction or with an energy harvester based on an eccentric mass with a generator with or without a battery.

[0011] Within the scope of the disclosure relating to the present invention, at least one capacitive element, in particular at least one capacitor, can also be used in combination with an energy harvester and / or induction instead of the at least one battery. This has the advantage that a battery with a comparatively high mass and thus mass inertia can be replaced by at least one significantly lighter capacitive element, in particular by at least one significantly lighter capacitor.

[0012] This also has a positive effect in the event of the occurrence or presence of imbalance(s), in that the sensors can be supplied with energy even at high speeds when using a capacitive element or capacitor, either in combination with an energy harvester and / or induction, which is not easily possible when using one (or more) batteries - as a speed-limiting factor.

[0013] Furthermore, capacitive elements or capacitors, unlike lithium polymer batteries, for example, are not classified as hazardous materials, which simplifies shipping and trade with respect to the present invention.

[0014] A special feature compared to the state of the art is that the compensating element (metal bellows) itself can serve as the base body for the strain gauges and to hold the sensor assembly. This eliminates the need for special solutions such as aluminum or steel tubes, flanges, or other substitute bodies that are conventionally used between two compensating elements, such as two bellows and an aluminum tube in the middle.

[0015] This makes the sensor coupling very compact, has a lower mass, a lower mass inertia and fewer interfaces between the components.

[0016] Such, particularly high-precision, metal bellows couplings can be used, especially as sensor couplings, wherever positioning accuracy is required, for example in medical technology, in test benches, in wind turbines or in highly dynamic servo axes, such as in machine tools, woodworking machines, packaging machines and the like. Short description of the drawings

[0017] There are various possibilities for advantageously embodying and developing the teachings of the present invention. For this purpose, further embodiments, features and advantages of the present invention are described with reference to the Fig. 2 are explained in more detail. The figures are not necessarily to scale; any design and dimensioning information in the figures is purely exemplary. Preferred embodiment of the present invention; best mode for carrying out the present invention

[0018] In Fig. 2 shows various embodiments of a metal bellows coupling according to the present invention.

[0019] The metal bellows coupling has two compensating elements arranged opposite one another (= several bellows corrugations each), a cylindrical hollow body arranged between the compensating elements in the manner of a flange or in the manner of a pipe, and a sensor device or sensor assembly arranged within the hollow body with associated sensor electronics.

[0020] The sensor device or sensor assembly can be fixed in the hollow body by elastically deformed O-rings, in particular glued or pressed.

[0021] The sensor device or sensor assembly can be assigned a radio antenna, in particular based on Bluetooth®, for the wireless or wireless transmission of sensor data determined by the sensor device or sensor assembly.

[0022] The sensor device or sensor assembly has strain gauges (SGs) that are arranged on the outside of the lateral surface of the hollow body and are covered and thus protected by a cover (e.g. housing or shrink tubing).

[0023] The outer surface of the hollow body has a hole through which the strain gauge cables, covered and thus protected by a cover (e.g., a housing or heat-shrink tubing), can be routed into the interior of the hollow body. Alternatively, the strain gauges can be arranged on the inside of the outer surface of the hollow body.

[0024] On the outside of the shell surface of the hollow body, an inductively acting wire winding is provided, covered and thus protected by a cover (e.g. housing or shrink tube), and at least one pick-up is provided as a separate component.

[0025] An energy converter for converting mechanical energy into electrical energy is provided on and / or within the lateral surface of the hollow body, wherein the mechanical energy is provided by a relative rotational movement of the energy converter relative to a rotational axis or hub or shaft of the energy converter and the rotational axis or hub or shaft of the energy converter can be held in position by gravity, in particular by at least one eccentric mass element, for example in the form of a plate or a plurality of mutually associated plates.

[0026] The energy converter can - as an excitation device or generator, in particular as a brushless or slip-ring-less excitation device and / or as a synchronous generator, and / or - be designed modularly, in particular as an independent or separate module.

[0027] A storage element, in particular a battery or an accumulator element and / or a capacitive element or a capacitor, for storing electrical energy, in particular for storing an excess portion of the electrical energy, can be provided on and / or within the lateral surface of the hollow body.

[0028] The compensation element is designed as a base body for the strain gauges (SGs) and to hold the sensor device or sensor assembly.

[0029] Such a particularly high-precision metal bellows coupling according to Fig.2 can be used, in particular as a sensor coupling, wherever positioning accuracy is required, for example in medical technology, in test benches, in wind turbines or in highly dynamic servo axes, such as in machine tools, woodworking machines, packaging machines and the like. List of reference symbols 10a hub 10b hub 12 metal bellows with bellows corrugations 20 Sectional view of the coupling 30 metal bellows couplings with different hub connections 40 bellows waves 42 bellows 50 tube with integrated sensors and strain gauge 52a Metal bellows 1 (compensating element) 52b Metal bellows 2 (compensating element) 60 flange with integrated sensors and strain gauge 62a Disc pack 1 (compensating element) 62b Disc pack 2 (compensating element) 70 hubs interchangeable according to customer requirements 72 Covering the winding, strain gauges and cable with housing or shrink tubing 74 Fastening of the sensor assembly by elastically deformed O-rings, glued or pressed 80 wire windings 82 Pickup

Claims

[1] Metal bellows coupling with at least two compensating elements arranged opposite one another, with at least one cylindrical hollow body arranged between the compensating elements, in particular in the manner of at least one flange or in particular in the manner of at least one pipe, and with at least one sensor device or sensor assembly arranged within the hollow body. [2] Metal bellows coupling according to claim 1, wherein one, two or more bellows corrugations are provided on each side of the metal bellows coupling as a compensating element. [3] Metal bellows coupling according to claim 1 or 2, wherein at least one sensor electronics is assigned to the sensor device or sensor assembly. [4] Metal bellows coupling according to at least one of claims 1 to 3, wherein the sensor device or sensor assembly is assigned at least one radio antenna, in particular based on Bluetooth®, provided for the wireless or cable-free transmission of sensor data determined by the sensor device or sensor assembly. [5] Metal bellows coupling according to at least one of claims 1 to 4, wherein the sensor device or sensor assembly comprises at least one strain gauge (DMS) arranged on the outside of the lateral surface of the hollow body. [6] Metal bellows coupling according to claim 5, wherein the outer surface of the hollow body has at least one bore by means of which at least one cable of the at least one strain gauge (DMS) can be guided into the interior of the hollow body. [7] Metal bellows coupling according to at least one of claims 1 to 4, wherein the sensor device or sensor assembly comprises at least one strain gauge (DMS) arranged on the inside of the lateral surface of the hollow body. [8] Metal bellows coupling according to at least one of claims 1 to 7, wherein at least one inductively acting wire winding is provided on the outside of the lateral surface of the hollow body and at least one pick-up is provided as a separate component. [9] Metal bellows coupling according to at least one of claims 1 to 8, wherein at least one energy converter for converting mechanical energy into electrical energy is provided on and / or within the outer surface of the hollow body. [10] Metal bellows coupling according to claim 9, wherein the mechanical energy is given by a relative rotational movement of the energy converter relative to a rotational axis or hub or shaft of the energy converter. [11] Metal bellows coupling according to claim 10, wherein the axis of rotation or hub or shaft of the energy converter is held in position by gravity, in particular by at least one eccentric mass element, for example in the form of a plate or several plates assigned to one another. [12] Metal bellows coupling according to at least one of claims 9 to 11, wherein the energy converter - as an excitation device or generator, in particular as a brushless or slip-ring-less excitation device and / or as a synchronous generator, and / or - is designed in a modular manner, in particular as an independent or separate module. [13] Metal bellows coupling according to at least one of claims 1 to 12, wherein at least one storage element, in particular at least one accumulator or at least one accumulator element and / or at least one capacitive element or at least one capacitor, is provided on and / or within the outer surface of the hollow body for storing electrical energy, in particular for storing an excess portion of the electrical energy. [14] Metal bellows coupling according to at least one of claims 1 to 13, wherein the compensating element is designed as a base body for the at least one strain gauge (DMS) and / or for holding the sensor device or sensor assembly. [15] Use of at least one metal bellows coupling according to at least one of claims 1 to 14 in medical technology, in test benches, in wind turbines or in highly dynamic servo axes, in particular of machine tools, woodworking machines, packaging machines and the like.

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