DE10114338B4 - Adaptionsflansch - Google Patents

Abstract

Adapter flange for coupling a shaft coupling, preferably all-steel coupling, with a Drehmomentaufnehmer in the course of a torque transmission, consisting of a torsionally rigid, flexible elastic shaft coupling and a torque-measuring coupling, characterized in that the adaptation flange (13, 23, 33) by a mainly radial undercut (13a , 23a, 33a) is divided into two partially interconnected partial flanges (13b, 23b, 33b), wherein a press cover (5) is inserted into the central recess (5a) of the adapter flange.

Description

The The invention relates to an adapter flange for coupling a shaft coupling (All-steel coupling) with an extensometer in the course of a torque transmission, consisting of a torsionally rigid, flexurally elastic shaft coupling and a torque-measuring clutch. The extensometer serves to provide a torque-proportional surface strain by means of strain gauges too measure up. It is for a reliable one Measurement of a homogeneous strain curve condition.

• – Die vorhandene Oberflächendehnung aufgrund des einwirkenden Drehmomentes muß unterhalb der plastischen Deformation des Aufnehmers liegen.
• – Die Dehnmeßstreifen müssen auf das Aufnehmermaterial abgestimmt sein (gleiche Wärmeausdehnungskoeffizienten).
• – Die Applikation muß dergestalt gewählt werden, daß Störgrößen (Temperatur, Biegung, Axialkraft) weitgehend kompensiert werden, andrerseits aber das Drehmoment mit möglichst hoher Empfindlichkeit gemessen wird.
• – Möglichst hohe Anzahl von Dehnmeßstreifen, um evtl. Inhomogenitäten (Krafteinleitung, Reaktionskräfte) auszugleichen, was zu hohen Kosten führt.
• – Homogener Dehnungsverlauf – keine punktuelle und unsymmetrische Krafteinleitung

When using the strain gauge technology for measuring the torque-proportional surface strain, the following criteria must be met:

• - The existing surface strain due to the applied torque must be below the plastic deformation of the transducer.
• - The strain gauges must be matched to the transducer material (same thermal expansion coefficients).
• - The application must be chosen such that disturbances (temperature, bending, axial force) are largely compensated, but on the other hand, the torque is measured with the highest possible sensitivity.
• - As high as possible of strain gauges to compensate for any inhomogeneities (force, reaction forces), which leads to high costs.
• - Homogeneous expansion curve - no punctiform and asymmetrical force application

In the prior art in the form of US 3,800,591 a strain gland is known, which has two thick-walled sections and a particularly thin-walled portion, are arranged on the measuring strip to the transmitted. To measure torque. The thin-walled portion is connected to the thick-walled portions via portions having radial grooves and thus acting as bellows couplings to reduce or prevent the transmission of bending moments.

The DE 19936293 shows a torque sensor with two axially spaced apart flanges. A torque transmission element, which also includes the cross-sectional areas in which the strain gauges are arranged, is located between the two connecting flanges, in each of which two radially offset opposite end-side inserted circumferential grooves are provided to form a hinge-like portion. These grooves are mounted in the axial direction and are intended to decouple the torque introduction via the screw connection of the flanges in the arranged between the flanges torque transmission element.

at the integration of a measuring shaft (an extensometer) exists in an existing shaft train always the problem of offset compensation between the two shaft ends. Remedy can be either by a correspondingly high cost in the alignment of the shafts and the production of the individual components or by suitable shaft compensation couplings.

By backlash-compensated couplings such as curved tooth couplings can cause reaction forces due to offset (friction lubrication), which act on the extensometer, are kept very low. Possibly. influences to the measured variable torque are thus largely prevented.

at absolutely backlash-free compensating couplings such as all-steel couplings Occur offset reaction forces that are significantly above those of game-based systems. By the punctual Force introduction, d. H. the screw connection of the disk set prevails an inhomogeneous strain distribution in the adapter flange and thus in the extensometer before. In addition, through the combination of different types of offset asymmetrical strain curves at the measuring points (DMS), the error compensation by suitable application to make impossible. As a consequence, reaction-related interference signals are superimposed on the actual measurement signal, which reduce the overall accuracy of a present measurement system.

The Adaptation of all-steel couplings with corresponding strain transducers As a rule, this is done by means of simple, as short as possible adaption flanges. these can the punctiform and non-uniform initiated forces due to the connection of the disk packs only insufficiently homogenize. As a result, occur in the combination of corresponding displacement components measurement error on, which are shown in Figure 3.

By a rotation of the clutch in the fully displaced state, related on the ensprechende angular positions (X-axis), the illustrated Zero offsets (Y axis). Determined measured values (torques) would be like that upon rotation of the clutch with a swelling signal with the superimposed level shown.

task The invention is caused by the acting reaction forces measurement error at least significantly lower.

This is done by a new design according to the invention of the adaptation flange. In order to the unwanted reaction forces generated by the compensating coupling are decoupled from the extensometer. As a result, the full displacement capability of the compensating coupling used can be claimed, without having to accept increased measurement errors.

The Essence of the invention results from the patent claim 1 and is according to the subclaims further training. In the following description are based on Pictures of a known and inventive designs of Adapter flange embodiments of the invention. Show in it

image 1 a torque measuring coupling in combination with an all-steel coupling after the St. d. T. with a usual Adapter flange short design;

image 2 an adapter flange short design of conventional design;

image 3 the measurement error due to axial misalignment, without additional torque load when using a conventional Adaptionsflansches;

image Fig. 4 shows the arrangement of Fig. 1 using a first embodiment the adaptation flange according to the invention;

image 5 shows an adaptation flange according to the invention with press cover;

image 6 the measurement error due to axial misalignment when using an adaptation flange according to the invention;

image 7 a modified Embodiment of the adaptation flange according to the invention;

image 8 an exploded view of an arrangement with an adaptation flange according to the invention.

In the conventional arrangement of Figure 1 are with 1 denotes the mutual hubs, 2 is the respective lamella pact, 3 the conventional adaptation flange, 4 the expansion sleeve for measuring the torque-proportional surface strain, 6 is a signal rotary transformer / stator electronics.

image Fig. 2 shows in plan view and two sections A-A and B-B the conventional one Adaptionsflansch.

The Measurement results After picture 3 were from a conventional clutch with a Nominal torque of 1600 Nm taken. A variation of the measuring signal for the Error torque of ± 27 Nm, as shown in Figure 3, thus corresponds to a measurement error of ± 1.7% from nominal torque of the coupling.

After picture 4 each adapter flange was 13 according to the invention by a mainly radial undercut 13a in two partial flanges 13b divided, which have remained connected to each other in the middle. They are preferably flat and preferably over the entire radius of the undercut 13a same thickness. They are also preferably of equal thickness relative to each other. But they can also be uneven and uneven thickness. The underdog 13a For example, runs exactly radially in a direction perpendicular to the axis of rotation D of the adaptation flange level E. The undercut 13a can also be at an acute angle to the plane E. This training is better in effect but more difficult to produce.

According to Figure 5, the adapter flange is in view and in sections AA and BB 23 with the undercut 23a and the partial flanges 23b shown. In addition, a press cover 5 in a recess 5a intended. By concentrating the power flow on the smallest possible cross-sections (undercut from the outside), the selective introduction of force on the disk pack side can be homogenized. At the same time the radial stiffness of the disk pack side is greatly increased by using a press cover, so that unbalanced radial force effects are transmitted only to a much lesser extent on the drive side (expansion sleeve). By this embodiment (undercut on small cross-sections - press cover with oversize) a significant reduction of the offset-related measurement error could be achieved. With a comparable displacement level, the error could be reduced from ± 27 Nm to ± 0.75 Nm (Figure 6). At a rated torque of 1600 Nm, this corresponds to an error of ± 0.05% of the nominal torque.

Figure 6 shows the results of a measurement analogous to the picture 3 but using an adaptation flange according to the invention. With the same risk of displacement as in the measurement according to FIG. 3, this measurement proves the advantages of the adaptation flange according to the invention, namely acceptance of higher axis offsets, a lower level of the error and an increased overall accuracy of the system.

In picture 7 in view and in sections AA and BB there is an adaptation flange 33 shown according to the invention, a press cover 5 in a hole 5a has. The radial undercut 33a can be very narrow, causing either the thickness of the partial flanges 33b increased or the overall length can be shortened.

This inventive adaptation flange undergoes a additional weakening in terms of axial and radial stiffness. This can be a more Decoupling of the disturbances achieved become. Application finds this embodiment, especially for large dimensions or at extreme clutch reaction forces.

By further reduction of the flange stiffness in the axial direction, as well Displacement of the interference fit on the outside diameter of the press cover can be an absolute decoupling of the reaction forces, simultaneously must however an additional Reduction in overall stiffness can be accepted. This allows lamella packages with high rigidity (large Power density) without additional increase the measurement error with strain gage hubs be coupled. At the same time, the full ability to shift remains the used compensating couplings obtained, d. H. without any Compromise regarding measurement accuracy and costs.

Figure 8 shows an exploded view, with the details of the adapter flange 3 . 13 . 23 . 33 not exposed.

Claims (6)

Adapter flange for coupling a shaft coupling, preferably all-steel coupling, with a torque transducer in the course of a torque transmission, consisting of a torsionally stiff, flexible elastic shaft coupling and a torque-measuring coupling, characterized in that the adaptation flange ( 13 . 23 . 33 ) by a mainly radial undercut ( 13a . 23a . 33a ) in two centrally connected partial flanges ( 13b . 23b . 33b ), wherein a press cover ( 5 ) in the central recess ( 5a ) of the adaptation flange is used. Adapter flange according to claim 1, characterized in that the undercut ( 13a ) in a plane (E) perpendicular to the axis of rotation (D) of the adapter flange ( 13 ) runs. Adapter flange according to claim 2, characterized that the partial flanges are flat. Adapter flange according to claim 2 or 3, characterized characterized in that the partial flanges equal over their entire radius are thick. Adapter flange according to claim 2, 3 or 4, characterized characterized in that the partial flanges in relation to each other the same thickness are. Adapter flange according to claim 1, characterized in that the puncture ( 13 ) at an acute angle to a plane (E) extending perpendicular to the axis of rotation (D) of the adaptation flange ( 13 ).