Method for determining a torque in a traction gear, traction gear and robot or vehicle

Abstract

Method for determining a torque in a traction device (100), the traction device (100) comprising a drive shaft, an output shaft and a traction element (102) with a first run (118) and a second run (120), wherein the torque is determined taking into account a first traction force in the first run (118) and a second traction force in the second run (120), traction device (100) comprising a drive shaft, an output shaft, a traction element (102) with a first run (118) and a second run (120), a first traction tensioner (104) associated with the first run (118) and a second traction tensioner (106) associated with the second run (120), wherein the traction device (100) is designed to perform such a method, and a robot or vehicle comprising such a traction device (100).

Description

[0001] The invention relates to a method for determining a torque in a traction device, the traction device comprising a drive shaft, an output shaft, and a traction element with a first run and a second run. The invention further relates to a traction device comprising a drive shaft, an output shaft, a traction element with a first run and a second run, a first traction element tensioner associated with the first run, and a second traction element tensioner associated with the second run. The invention also relates to a robot or a vehicle.

[0002] Document DE 196 16 574A1 discloses a device for measuring the tension of a belt in a tensioned state, comprising: a vibration application device for applying a vibration to the belt with a frequency that varies within a predetermined frequency range covering the resonant vibration frequency of the belt; a vibration amplitude detection device for detecting the amplitude of the belt vibrations and outputting a corresponding amplitude signal; and a tension detection device for detecting the occurrence of a resonance of the belt based on the output signal of the vibration amplitude detection device and for identifying a vibration frequency of the belt, detected when the resonance occurs, as the resonant vibration frequency of the belt, in order to determine the tension of the belt based on the resonant vibration frequency.

[0003] Document DE 10 2016 010 551 B3 discloses a torque sensor with a base body that extends in a radial direction from an annular inner flange with first force application points via a mechanically weakened sensor section equipped with output signal-generating measuring transducers to an annular outer flange with second force application points, characterized in that the second force application points are connected to the sensor section by a radially elastic material section.

[0004] The invention is based on the objective of structurally and / or functionally improving a method mentioned above. Furthermore, the invention is based on the objective of structurally and / or functionally improving a traction device mentioned above. Additionally, the invention is based on the objective of structurally and / or functionally improving a robot or vehicle mentioned above.

[0005] The problem is solved by a method having the features of claim 1. Furthermore, the problem is solved by a traction device having the features of claim 6. Furthermore, the problem is solved by a robot or a vehicle having the features of claim 10. Advantageous embodiments and / or further developments are the subject of the dependent claims.

[0006] The method according to the invention is designed to determine a torque in a traction drive comprising a drive shaft, an output shaft, and a traction element with a first run and a second run. The torque is determined taking into account a first traction force in the first run and a second traction force in the second run. The traction element may have a longitudinal axis. A traction force may be a force acting along the longitudinal axis of the traction element. The torque can be determined based on the first traction force and the second traction force. The torque can be determined indirectly or by calculation.

[0007] The first and second tensile forces can be determined or measured differentially. A difference in tensile forces can be calculated from these two forces. The torque can then be determined taking this difference into account.

[0008] The method can be designed to determine a torque in a traction drive that has a first traction tensioner associated with the first run and / or a second traction tensioner associated with the second run. A first traction tension force of the first traction tensioner can be determined or measured. A second traction tension force of the second traction tensioner can be determined or measured. A traction tension force can be a force acting perpendicular to the longitudinal axis of the traction element. The traction element can have a first entry angle and a first exit angle at the first traction tensioner, in particular at a tensioning roller of the first traction tensioner. The traction element can have a second entry angle and a second exit angle at the second traction tensioner, in particular at a tensioning roller of the second traction tensioner.

[0009] The method can be designed to determine a torque in a traction device in which the first traction tensioner has at least one first elastic element and / or the second traction tensioner has at least one second elastic element.

[0010] A first change in displacement and / or a first change in shape can be detected at the first elastic element. A second change in displacement and / or a second change in shape can be detected at the second elastic element. A change in displacement can be detected as a change in distance between two reference points. A change in shape can be detected on a surface of an elastic element.

[0011] The tensile force can be determined during assembly. The tensile force can also be determined during operation of the traction drive.

[0012] The traction device according to the invention comprises a drive shaft, an output shaft, a traction element with a first run and a second run, a first traction element tensioner associated with the first run, and a second traction element tensioner associated with the second run. The traction device can be a friction-fit and / or positive-fit traction device. The drive shaft can have a drive shaft axis of rotation. The output shaft can have an output shaft axis of rotation. The drive shaft axis of rotation and the output shaft axis of rotation can be parallel to and spaced apart from each other. The drive shaft can have a drive pulley. The output shaft can have an output pulley. The drive pulley and the output pulley can have different diameters. The traction element can have a drive wrap angle on the drive shaft or drive pulley.The traction element can have an output wrap angle on the output shaft or output pulley. The traction element can be flexible and elastic. The traction element can be articulated. The traction element can be fully enclosed. The traction element can wrap around the drive shaft or drive pulley on one side and the output shaft or output pulley on the other. The traction element can be force-transmittingly connected to the drive shaft or drive pulley on one side and to the output shaft or output pulley on the other. The traction element can be a belt, in particular a flat belt, V-belt, multi-ribbed belt, or toothed belt, or a chain, in particular a link chain or articulated chain. The first strand can be a load strand and the second strand can be an unloaded strand. A traction element tensioner can include a tensioning roller.The tensioning roller can have a tensioning roller diameter. The traction drive is designed to carry out the method according to the invention.

[0013] The first and second tensioning devices can be arranged symmetrically. The tensioning device can have a distance axis between the input shaft axis of rotation and the output shaft axis of rotation. The first and second tensioning devices can be arranged symmetrically with respect to this distance axis. The distance axis can also be an axis of symmetry.

[0014] The first tensioning device can have at least one first elastic element. The second tensioning device can have at least one second elastic element. An elastic element can be designed as a spring or as an elastic component. An elastic element can be torsionally elastic or flexurally elastic. An elastic element can be beam-shaped. The tensioning device can have at least one first sensor for detecting a first change in displacement and / or a first change in shape on the at least one first elastic element. The tensioning device can have at least one second sensor for detecting a second change in displacement and / or a second change in shape on the at least one second elastic element. A sensor can be a distance sensor or a displacement sensor. A sensor can be a force sensor or a torque sensor, for example, a strain gauge.

[0015] The traction transmission may include an electronic control device. The electronic control device may be designed to determine a torque in the traction transmission taking into account signals from the first sensor and / or signals from the second sensor. The electronic control device may include a processor, working memory, data storage, a signal input, and / or a signal output. The at least one first sensor and / or the at least one second sensor may be connected to the electronic control device via signal transmission.

[0016] The robot or vehicle according to the invention comprises the traction device according to the invention. The robot may have robot limbs and robot joints. The traction device may be designed and / or arranged to move the robot limbs and / or robot joints.

[0017] In summary, the invention provides, among other things, a differential torque determination in traction drives. The torque can be determined by differentially measuring the tensile forces in the belts. Symmetrically arranged belt tensioners can be used to measure the tensile forces. Existing belt tensioners can be easily integrated without additional mechanics. Force measurement at the belt tensioner can be achieved using a spring with displacement measurement, an elastic component with strain gauges, or other methods. Belt tension can be checked during assembly. Belt tension can also be checked during operation.

[0018] The invention utilizes the properties of a traction drive to not only transmit and, if necessary, translate torque, but also to determine or measure it in a disturbance-free and linear manner. Direct torque measurement at a drive shaft is not required. High levels of nonlinearity and disturbances caused by the elastic properties of the traction element and the mechanics are reduced or avoided.

[0019] Exemplary embodiments of the invention are described in more detail below with reference to the figures, which show schematically and by way of example: Fig. 1 a traction gear with two traction tensioners for determining a torque, Fig. 2 measured values ​​from two tensioning devices and Fig. 3 an average of measured values ​​from two tensioning devices

[0020] Fig. Figure 1 shows a traction gear 100 with a drive shaft, an output shaft, a traction element 102, a first traction element tensioner 104 and a second traction element tensioner 106.

[0021] The drive shaft has a drive shaft axis of rotation 108 and a drive pulley 110. The output shaft has an output shaft axis of rotation 112 and an output pulley 114. The drive shaft axis of rotation 108 and the output shaft axis of rotation 112 are parallel to each other and spaced apart. The drive pulley 110 has a radius. The output pulley 110 has a radius r. p3 a distance axis 116 is formed between the drive shaft rotation axis 108 and the output shaft rotation axis 112.

[0022] The traction element 106 is completely enclosed and wraps around the drive disc 110 with a drive wrap angle τ p2 and the output disk 114 with an output wrap angle τ p3. Sections of the traction element 106 located between the drive pulley 110 and the output pulley 114 form a first run 118 and a second run 120.

[0023] The first tensioning device 104 has a tensioning roller 122 and a beam-shaped elastic element 124 and is arranged on the first section 118 for tensioning the tensioning device 102. The tensioning device 102 has a first entry angle γ1 and a first exit angle γ2 at the tensioning roller 122 of the first tensioning device 104. The second tensioning device 106 has a tensioning roller 126 and a beam-shaped elastic element 128 and is arranged on the second section 120 for tensioning the tensioning device 102. The tensioning device 102 has a second entry angle and a second exit angle at the tensioning roller 126 of the second tensioning device 106. The tensioning devices 104 and 106 are arranged symmetrically with respect to the distance axis 116. A strain gauge is arranged on the elastic element 124 of the first tensioning device 104 as a first sensor 130 for detecting a first change in shape of the elastic element 124.A strain gauge is arranged on the elastic element 128 of the second tensioning device 106 as a second sensor 132 for detecting a second deformation of the elastic element 128.

[0024] A pretension of the traction element 102 can be set via a respective adjusting screw on the traction element tensioner 104, 106 and the respective force acting on the belt tensioners can be sensed in them by detecting the surface tension on their elastic elements 124, 128 which are deformed under load.

[0025] During motion or force transmission between the drive pulley 110 and the driven pulley 114, one section 118 or 120 forms a load-bearing section and the other section 120 or 118 a slack section. This is reflected in the force measurement at the two tensioning devices 104 and 106. A tensile force in the tensioning device 102 is related to the transmitted torque. Due to the non-linear elastic behavior of the tensioning device 102, in both the load-bearing and slack sections, the relationship between a single force measurement at the tensioning device and the acting torque is also non-linear, as shown in diagram 200. Fig. 2. Area 202 corresponds to the ratio of the actual torque τ and the force measurement d of the first tensioning device 104 at different rotational speeds θ̇̇. Area 204 corresponds to the second tensioning device 106. Due to the symmetrical arrangement of the tensioning devices 104, 106 in the two sections 118, 120 and their coupling by the common tensioning device 102, the nonlinearities and mechanical disturbances cancel each other out when averaging the two force measurements, thus enabling a linear and low-noise torque measurement. This average value is shown in diagram 300. Fig. Figure 3 is shown as area 302. It is evident that a large proportion of the nonlinearities and mechanical disturbances cancel each other out, thus enabling a linear and low-noise torque measurement.

[0026] The term "may" refers in particular to optional features of the invention. Accordingly, there are also further developments and / or embodiments of the invention that additionally or alternatively include the respective feature(s).

[0027] From the combinations of features disclosed in the description, paragraphs

[0001] to

[0025] , features can, if necessary, be selected and used alone or in combination with other features to define the subject matter of the claim, dissolving any structural and / or functional relationship that may exist between the features. Reference sign 100 traction gears 102 traction elements 104 first tensioner 106 second tensioner 108 Drive shaft rotation axis 110 Drive pulley 112 Output shaft rotation axis 114 Output disc 116 Distance axis 118 first tower 120 second tower 122 Tension pulley 124 elastic elements 126 Tension pulley 128 elastic element 130 first sensor 132 second sensor 200 Diagram 202 area 204 area 300 Diagram 302 area QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 196 16 574A1

[0002] DE 10 2016 010 551 B3

[0003]

Claims

[1] Method for determining a torque in a traction gear (100), the traction gear (100) comprising a drive shaft, an output shaft and a traction element (102) with a first run (118) and a second run (120), characterized by , that the torque is determined taking into account a first traction force in the first phase (118) and a second traction force in the second phase (120). [2] Method according to claim 1, characterized by that the first traction force and the second traction force are determined or recorded differentially. [3] Method according to at least one of the preceding claims, wherein the traction gear (100) has a first traction tensioner (104) associated with the first run (118) and a second traction tensioner (106) associated with the second run (120), characterized by, that a first tension force of the first tension tensioner (104) and a second tension force of the second tension tensioner (106) are determined or recorded. [4] Method according to claim 3, characterized by , that the first tensioning device (104) has at least one first elastic element (124) and / or the second tensioning device (106) has at least one second elastic element (128) and that a first change in displacement and / or a first change in shape and / or a second change in displacement and / or a second change in shape are detected on the at least one first elastic element (124) and on the at least one second elastic element (128). [5] Method according to at least one of the preceding claims, characterized by , that a traction force is determined during assembly and / or operation of the traction gear (100). [6] Traction gear (100) comprising a drive shaft, an output shaft, a traction element (102) comprising a first run (118) and a second run (120), a first traction element tensioner (104) associated with the first run (118) and a second traction element tensioner (106) associated with the second run (120), characterized by , that the traction gear (100) is designed to perform a method according to at least one of claims 1 to 5. [7] Traction gear (100) according to claim 6, characterized by , that the first tensioning device (104) and the second tensioning device (106) are arranged symmetrically. [8] Traction gear (100) according to at least one of claims 6 to 7, characterized by, that the first tensioning device (104) has at least one first elastic element (124) and / or the second tensioning device (106) has at least one second elastic element (128) and the tensioning device (100) has at least one first sensor (130) for detecting a first change in position and / or a first change in shape on the at least one first elastic element (124) and / or at least one second sensor (132) for detecting a second change in position and / or a second change in shape on the at least one second elastic element (128). [9] Traction gear (100) according to claim 8, characterized by , that the traction gear (100) has an electronic control device for determining a torque in the traction gear (100) taking into account signals from the first sensor (130) and / or signals from the second sensor (132). [10] robot or vehicle, characterized bythat the robot or vehicle has a traction transmission (100) according to at least one of claims 6 to 9.

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