DE10114338A1 - Adaptor flange couples all-steel shaft union with a torque drive - Google Patents

Abstract

An adaptor flange couples an all-steel shaft union with a torque drive. The flange is stiff in rotation but otherwise elastic. The adapter flange (13, 23, 33) has a mainly radial relief groove (13a, 23a, 33a) in two part-flanges (13b, 23b, 33b) linked at the middle.

Description

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 coupling. The stretch absorption mer serves to generate a torque-proportional surface expansion To measure strain gauges. Here is a reliable measurement homogeneous strain curve condition.

When using the strain gauge technology to measure the torque-proportional surface elongation, the following criteria must be met:

• - The existing surface expansion due to the acting torque mentes must be below the plastic deformation of the transducer.
• - The strain gauges must be matched to the transducer material (same coefficient of thermal expansion).  
• - The application must be selected in such a way that disturbance variables (tempera ture, bending, axial force) are largely compensated for, but on the other hand the torque is measured with the highest possible sensitivity.
• - The greatest possible number of strain gauges to avoid possible inhomogeneities (Force introduction, reaction forces) to compensate, which leads to high costs.
• - Homogeneous strain curve - no selective and asymmetrical force introduction

When integrating a measuring shaft (a strain gauge) into a front existing shaft strand there is always the problem of offset compensation between between both shaft ends. Remedy can either be by a high effort in aligning the shafts and manufacturing the Individual components or through suitable shaft balancing couplings be opened.

Due to playful compensating couplings such as curved tooth couplings displacement-related reaction forces (friction-lubrication) that affect the deh act on the sensor, be kept very low. Possibly. Influences on the Measured variable torque is thus largely prevented.

With absolutely play-free compensating couplings such as all-steel Clutches experience offset reaction forces that are significantly above of those systems with play. Due to the selective application of force, d. H. the screw connection of the plate pack is inhomogeneous distribution in the adapter flange and thus in the strain sensor. In addition, by combining different types of offsets symmetrical strain curves occur at the measuring points (DMS), the one Make error compensation impossible by suitable application. As a result of this, the actual measurement signal becomes reaction-related interference signals  superimposed, which reduce the overall accuracy of an existing measuring system ren.

The adaptation of all-steel couplings with appropriate expansion transducers is usually carried out using simple, as short as possible adaptation flanges. Due to the connection of the plate packs, these can only insufficiently homogenize the forces that are introduced selectively and irregularly. As a result, measurement errors occur when combining the corresponding displacement components, which are shown in Figure 3.

Pedal by rotating the clutch in the fully shifted state to the corresponding angular positions (X-axis), the zero point shown shifts (Y axis). Measured values (torques) would be so with when the clutch rotates with a swelling signal with the darge level superimposed.

The object of the invention is to ver by the acting reaction forces cause measurement errors to be reduced at least considerably.

This is done by a new design of the adaptation according to the invention flange. So that the generated by the compensating coupling, un desired reaction forces decoupled from the strain sensor. hereby can the full displacement ability of the compensating coupling used in Be claimed without having to accept increased measurement errors have to.

The essence of the invention results from claim 1 and is developed according to the subclaims. In the following description, examples of the invention are described with the aid of pictures of a known and of the construction of the adapter flange according to the invention. Figure 1 shows a torque measuring coupling in combination with an all-steel coupling according to the St. d. T. with a conventional adapter flange short design;

Figure 2 an adapter flange of short design of conventional design;

Figure 3 shows the measurement error due to axis misalignment when idling, without additional torque load when using a conventional adaptation flange;

Figure 4 shows the arrangement of Figure 1 using a first embodiment form of the adapter flange according to the invention;

Figure 5 a Adaptionsflansch invention with pressing lid;

Figure 6 shows the measurement error due to axis misalignment when using an adaptation flange according to the invention;

Figure 7 shows a modified embodiment of the adapter flange according to the invention;

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

In the conventional arrangement of Figure 1, 1 denotes the bilateral hub, 2 is the respective plate compact, 3 is the conventional adapter flange, 4 is the expansion sleeve for measuring the torque-proportional surface expansion, 6 is a rotary signal transmitter / stator electronics.

Figure 2 shows a top view and two sections AA and BB of the conventional adapter flange.

The measurement results according to Figure 3 were taken from a conventional clutch with a nominal torque of 1600 Nm. A variation of the measurement signal for the error torque of ± 27 Nm, as shown in Figure 3, corresponds to a measurement error of ± 1.7% of the nominal torque of the clutch.

According to Fig 4, each Adaptionsflansch 13 was divided according to the invention b by a mainly radial undercut 13 a into two partial flanges 13, which are still connected to each other centrally. They are preferably flat and preferably have the same thickness over the entire radius of the undercut 13 a. They are also preferably of the same thickness in relation to one another. But they can also be uneven and of uneven thickness. The undercut 13 a extends, for example, exactly radially in a plane E which is perpendicular to the axis of rotation D of the adapter flange E. The undercut 13 a can also run at an acute angle to the plane E. This training is better in effect, but it is more difficult to produce.

According to Figure 5 in view and in sections AA and BB of Adaptionsflansch 23 with the undercut 23 a and the partial flanges 23 b is shown. In addition, a press cover 5 is provided in a recess 5 a. By concentrating the power flow on the smallest possible cross-sections (undercut from outside), the selective application of force on the plate pack side can be homogenized. At the same time, the radial rigidity of the disk pack side is greatly increased by using a press cover, so that asymmetrical radial force effects are only transmitted to the drive side (expansion sleeve) to a greatly weakened extent. This embodiment (undercut to small cross-sections press cover with oversize) was able to achieve a considerable reduction in the measurement error due to the set. With a comparable displacement level, the error could be reduced from ± 27 Nm to ± 0.75 Nm ( Figure 6). With a nominal torque of 1600 Nm, this corresponds to an error of ± 0.05% of the nominal torque.

Figure 6 shows the measurement results for a measurement analogous to that of Figure 3, but using an adaptation flange according to the invention. This measurement proves, with the same risk of displacement as with the measurement according to Figure 3, the advantages of the adapter flange according to the invention, namely with an acceptance of higher axis misalignments, a lower level of error and an increased overall accuracy of the system.

In Figure 7, an adapter flange 33 according to the invention is shown in view and in sections AA and BB, which has a press cover 5 in a bore 5 a. The radial undercut 33 a can be very narrow, which can either increase the thickness of the partial flanges 33 b or shorten the overall length.

This adapter flange according to the invention is additionally weakened in terms of axial and radial rigidity. This allows a stronger Ent coupling of the disturbance variables can be achieved. This configuration is used especially with large dimensions or with extreme coupling conditions reaction forces.

By further reducing the flange stiffness in the axial direction, as well as Verla The press fit on the outside diameter of the press cover can be reduced absolute decoupling of the reaction forces take place, however, at the same time an additional reduction in overall stiffness can be accepted. here by means of plate packs with high rigidity (high power density) without additional increase in the measurement error coupled with strain gauge measuring hubs the. At the same time, the compensating couplings used remain fully displaceable  received, d. H. without any compromise regarding measurement accuracy speed and costs.

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

Claims (7)

1. Adaptation flange for coupling a shaft coupling, preferably a steel coupling, with a torque transducer in the course of a torque transmission, consisting of a torsionally rigid, flexible shaft coupling and a torque measuring coupling, characterized in that the adaptation flange ( 13 , 23 , 33 ) by a Mainly radial undercut ( 13 a, 23 a, 33 a) is divided into two centrally connected partial flanges ( 13 b, 23 b, 33 b). 2. adaptation flange according to claim 1, characterized in that the undercut ( 13 a) in a plane (E) perpendicular to the axis of rotation (D) of the adapter flange ( 13 ). 3. adaptation flange according to claim 2, characterized in that the partial flange are just. 4. adaptation flange according to claim 2 or 3, characterized in that the Partial flanges are of equal thickness over their entire radius. 5. adaptation flange according to claim 2, 3 or 4, characterized in that the Partial flanges are of equal thickness in relation to each other.   6. adapter flange according to claim 1, characterized in that the recess ( 13 ) extends at an acute angle to a plane (E) which extends perpendicular to the axis of rotation (D) of the adapter flange ( 13 ). 7. adaptation flange according to one of the preceding claims, characterized by a press cover ( 5 ) inserted into a central recess ( 5 a).