DE102012023679C5 - Position securing element, rotary encoder system with a position securing element and method for fastening a rotary encoder system - Google Patents

Abstract

The invention relates to a position securing element (50) for a rotary encoder system (14), wherein the rotary encoder system (14) has a rotary encoder (16) and a tolerance compensating connecting piece (18) and for detecting revolutions of a measuring shaft (26) of a measuring object to be monitored (12 ), wherein the position securing element (50) is releasably connectable to a transmitter housing (42) of the rotary encoder (16) and the connecting piece (18) and is adapted, in a joined state, the transmitter housing (42) and the connecting piece (18) set in a relative position to each other. The invention further relates to a rotary encoder system (14) having a position securing element (50), a measuring system (10) having a measuring object (12) and a rotary encoder system (14), and a method for fastening a rotary encoder system (14) to a measuring object (12). ,

Description

The present invention relates to a position assurance element for a rotary encoder system and to a rotary encoder system with a rotary encoder for detecting revolutions of a measuring shaft of a measuring object to be monitored. The invention further relates to a measuring system with a measuring object and a rotary encoder system and to a method for fastening a rotary encoder system to a measuring object.

From the EP 1 557 643 A1 is a rotation angle measuring device with a rotary encoder and an encoder shaft, which is mounted in a housing, and known with a stator coupling for the rotationally fixed connection of the encoder housing to a stationary part of a drive system to be measured, wherein the stator coupling has a torque arm. The torque arm is provided with at least two first attachment tabs for attachment to the encoder housing and at least two second attachment tabs for attachment to the stationary part.

From the DE 102 16 376 A1 a Drehwinkelmesssystem is known, comprising a device for torsionally stiff mechanical connection of a stator and a shaft of the measuring system with a stator or a shaft of a drive system to be measured, wherein the stator connection is realized by a stator coupling, which consists of a resilient element and represents a radially and axially resilient mechanical connection, and wherein the rotation angle measuring system has control elements that connect the shaft of the measuring system against rotation with the housing during assembly.

From the DE 10 2006 056 461 A1 a rotary encoder comprising a first group of components and a second group of components is known, wherein the second group of components comprises a code disk, a shaft with a central bore, a shoulder and a web with an outer surface, a ring body with an inner surface and an actuating means, as well as a component which is arranged between the outer surface and the inner surface of the annular body, and wherein the annular body is supported by the actuating means on the shoulder that over the component an inserted into the bore of the shaft machine part is radially clamped.

From the DE 10 2004 027 348 A1 is an angle measuring device for measuring the angular position of two relatively rotatable objects known with a stator, a rotatably mounted on the stator rotor and a coupling, by means of which the stator is axially resiliently coupled to one of the objects rotatable to each other, wherein a transport lock provided, which Coupling with an axial stop surface engages over such that it limits the mobility of the coupling in the axial direction, wherein the axial stop surface is spaced in the equilibrium position of the coupling in the axial direction of the coupling.

From the DE 20 2006 010 183 U1 an angle measuring device is known, comprising two units, wherein the first unit is rotatable relative to the second unit about an axis, arranged on the second unit coupling having an elastic spring behavior in the direction of the axis, and a locking member, wherein the angle measuring device to a Machine part is attachable, wherein in non-preloaded coupling a free gap between the machine part and the second unit is present with an extension in the direction of the axis, and wherein the locking element can be brought from a neutral position into a locking position, in which at least a portion of the locking element in Active connection with the second unit is.

From the EP 1 517 121 A2 a rotary encoder is known, wherein the rotary encoder has a transmitter body and a rotatably mounted in the encoder body encoder shaft, the encoder shaft is rigidly coupled with a shaft to be measured, the encoder is torsionally rigid and at least axially resiliently mounted in the housing, wherein the housing rigid is attached to a mounting surface, wherein on the housing a locking member is arranged, wherein the locking member between a locking position and a release position is movable, wherein the locking member engages in the locking position on the rotary encoder and this at least axially fixed with respect to the housing, and wherein the locking member is in the release position disengaged from the rotary encoder and allows its resilient mobility in the housing.

Encoder systems are well known in the art. Encoder systems are usually designed to detect partial or complete revolutions of a measuring shaft. Encoder systems can be used, for example, in drive technology, automation technology, transport technology or in power engineering. Rotary encoder systems usually have rotary encoders, which in principle can be configured to detect rotational angles or angles of rotation and / or rotational speeds of rotating components of a measuring object absolutely and / or relatively. For example, a relative measurement can also be called an incremental measurement.

By means of a rotary encoder, approximately an angular position in the range between 0 ° and 360 ° ( single turn) and / or a number of complete revolutions (multi turn) of a DUT are determined. Conventional DUTs may be designed as motors or transmissions. A rotating component of the measurement object whose movement is to be detected can be referred to as a measuring shaft, for example.

The assembly of the rotary encoder can make high demands on the alignment between the measuring shaft and an encoder shaft of the rotary encoder, especially in the case of play-related, high-speed and / or highly loaded measuring waves. In principle, it may be desirable to align the measuring shaft and the encoder shaft with one another as "as possible", ie in particular concentrically. However, a large number of applications is conceivable in which static and / or dynamic displacements, in particular of the measuring shaft, can occur. Such shifts should be compensated as possible by the encoder. Otherwise, an excessive wear or even a failure of the encoder could threaten.

In particular, shock loads can cause deformations of the measuring shaft, which can affect the encoder shaft and can affect the reliability of the encoder as a whole. Jerky loads can occur, for example, in out-of-round machines, such as internal combustion engines, presses or the like. However, shock loads can also occur during load changes and / or abrupt acceleration or deceleration on the measuring shaft.

Known encoder systems have exemplary elastic shaft couplings for tolerance compensation, which can be switched between the measuring shaft and the encoder shaft. Elastic shaft couplings can in particular have yielding, tolerance-compensating elements, so that positional deviations of the measuring shaft can not act directly on the encoder shaft. However, such solutions are often subject to the disadvantage that yielding shaft couplings increase the measurement inaccuracy. The shaft couplings "dampen" the detected rotation signal. Furthermore, there is the disadvantage that yielding shaft couplings, also called compensating couplings, require a certain amount of space, which is greater, the more tolerant the coupling should react to positional deviations.

An alternative approach to the design of encoder systems based on the encoder shaft as rigid as possible and directly to the measuring shaft (also: drive shaft) to connect. It is deliberately accepted that the encoder shaft immediately reproduces misalignments or positional deviations of the measuring shaft. This has the advantage that the measurement can be carried out with high precision and "unfiltered". In this design, it is advantageous to attach a housing of the rotary encoder on the measurement object such that a tolerance compensation is possible. However, it must be ensured that the housing of the rotary encoder does not twist as far as possible relative to the test object. This would lead to an increase in the measurement inaccuracy. However, it is desirable to take the housing of the rotary encoder "enough" to compensate for deviations in the position of the measuring shaft can. For example, an at least partially compliant housing coupling can be installed between the rotary encoder and the measurement object.

Submitted in the name of the Applicant of this application German utility model application, file number 20 2011 107 029.1 , filed October 17, 2011, which is not pre-published, describes advantageous designs of such compliant housing couplings. These are also referred to as connecting pieces and can provide an at least partially molded, tolerance-compensating anti-twist between the housing of the rotary encoder and a housing part of the measurement object in the mounted state. Various configurations make it possible to provide housing couplings (or: connecting pieces) which require only minimal axial space between the object to be measured and the rotary encoder.

The invention has the object to further develop the prior art and in particular to improve the handling and assembly of encoder systems. In particular, the assembly should be simplified as possible and be designed fault tolerant. Furthermore, necessary adjustment work should be reduced to a minimum.

This object is achieved by a position assurance element according to the independent device claim.

The object of the invention is completely solved in this way.

In accordance with the invention, the position-securing element can contribute to securing and / or stiffening the rotary encoder and the connecting piece in a preferred position during assembly, but also during storage and transport. In this way, especially during assembly of the encoder system, the desired position assignment between the encoder and the connector can be maintained. This may include in particular that the assembly of the encoder system can be done without a potentially adverse bias on the connector produce. The connection piece can basically also be called a stator coupling.

It is preferable to be able to mount the rotary encoder system in such a way that, as far as possible, the connecting piece is not loaded with a bias in a so-called neutral position. In this way, the connection piece can act in a desired manner in a tolerance-compensating manner in an operating state, for example when a measuring shaft of the measurement object deforms or shifts.

The rotary encoder system can be in a so-called joined state, for example, when the rotary encoder and the connecting piece are fixed to one another in the desired relative position or preferred position by means of the position-securing element. The relative position may comprise a defined axial and / or radial relative position. The relative position can also refer to a concentricity between the connector and the encoder. It is understood that the position assurance element can also be configured such that in the assembled state of the encoder and the connector are set under slight bias in the desired relative position to each other. However, this can be a defined preload. In particular, it is preferred in this context if a pretension caused in such a way in the assembled state can be reduced by the encoder system when the position-securing element is released.

Advantageously, the position assurance element is configured to transmit user actions, such as assembly forces and the like, to a considerable extent on the connector. This may in particular apply to an axial force applied by the operator when mounting the encoder system. The axial force can be generated by loading the rotary encoder system in a longitudinal direction or mounting direction in the direction of the measured object to be monitored.

By means of the position assurance element, a disadvantage of known rotary encoder systems can be overcome. For the purpose of tolerance compensation, it is customary to make the connecting piece (or the so-called stator coupling) yielding in certain spatial directions or spatial axes. However, this compliance can be detrimental during assembly and during transport or storage. The position assurance element can impart improved rigidity and robustness to the encoder system in the assembled state.

It will be understood that detecting revolutions of the measuring shaft may include detecting partial revolutions and / or detecting complete revolutions. Likewise, speeds, angles of rotation, rotational speeds and / or rotational accelerations can be detected.

According to a further embodiment, the position securing element has a base, from which extends at least one lateral leg, wherein on at least one leg contact elements are formed, which contact the encoder housing and / or the connector in the assembled state, wherein the contact elements preferably axial spacers and / or radial spacers.

The axial spacers and the radial spacers can be generally summarized by the term spacers. The spacers may be designed to set a defined axial distance and / or a radial distance in the joined state of the position-securing element between the connection piece and the rotary encoder. It is understood that spacers are also conceivable which define both a radial and an axial distance. The legs of the position assurance element may be referred to as a boom or support arms. The contact elements can contact the encoder housing and / or the connecting piece in a force-locking and / or form-fitting manner.

The at least one lateral limb, preferably the at least two lateral limbs of the position-securing element, can extend substantially parallel to an (imaginary) longitudinal axis of the rotary encoder system. A plurality of lateral limbs may be disposed approximately substantially mirror-symmetrically or rotationally symmetrically about the longitudinal axis.

According to a further embodiment, the position securing element has a bow-shaped or spider-like configuration with a plurality of lateral legs extending from the base, wherein the position securing element can engage around the encoder housing starting from its rear side, which faces away from the connecting piece.

The rear side of the rotary encoder or the encoder housing is the side that faces away from the DUT in the mounted state of the encoder system. The back side is usually the side most easily accessible to an operator or fitter. For assembly purposes, however, it is advantageous to be able to act as defined on the connector, but which is usually attached to a front side of the encoder or the encoder housing. The front side is the side facing the measurement object in the mounted state. The A bow-shaped or spider-like position securing element can embrace the encoder housing and provide a possibility of acting on the front-side connecting piece starting from the rear side. In this way, about an axial force or radial force can be applied substantially to the connector, without burdening the encoder excessively and / or to clamp the connector relative to the encoder.

By way of example, the position securing element may also be designed in the shape of a kraken, wherein the legs may correspond to the arms of an octopus and the base to the trunk or head. If the position assurance element has exactly two lateral legs, an approximately U-shaped configuration can result.

In an advantageous embodiment, the base of the position assurance element in the assembled state is spaced from the encoder housing. In this way it is ensured that from the rear (from the rear side) no significant axial load can act on the encoder housing of the encoder. Rather, the one or more legs of the position assurance element can transmit an axial force directly and essentially without the inclusion of the rotary encoder on the connector.

It is further preferred if the base has a recess, which is arranged in particular centrally. The recess can provide approximately a passage for a tool with which the encoder system can be attached to the measurement object. In this way, about a fastener, which is arranged concentrically to a longitudinal axis of the measuring shaft or a sensor shaft of the rotary encoder, are actuated starting from the rear side of the rotary encoder. It is understood that according to an alternative embodiment, the base can also be designed such that a central region of the rear side of the rotary encoder is not covered by the base. The central region can be an area through which a (imaginary) longitudinal axis of a sensor shaft or measuring shaft runs in the assembled state.

In an advantageous development, at least one lateral limb of the position-securing element has a handling section, which in particular has a structuring, wherein the handling section is provided at a base-side end of the limb. The structuring may be, for example, a corrugation, knurling or similar raised and / or recessed structures. In particular, it may be a structuring which gives the handling section a high "grip".

In a preferred development, the position securing element has at least two handling sections, which are in particular formed on opposite legs, wherein a radial pressure on the handling sections in the joined state causes a defined deformation of the position securing element. The radial pressure on the handling sections can in particular be applied radially inwards in the direction of a (imaginary) longitudinal axis, to which the legs of the position-securing element are arranged substantially parallel.

According to a further embodiment, the position securing element has at least one cohesive joint, which is deformable, at least in the joined state, by pressure on the at least one handling section in such a way that at least one contact element, in particular an axial spacer, is displaced around the position securing element without tools Be able to solve state.

The cohesive joint may be, for example, a defined section of a leg or the base of the position-securing element, which is deliberately thin-walled by way of example. It is understood that the position securing element can be deformable as a whole if the at least one handling incision is acted upon. However, it may be advantageous to design certain sections such that a defined deformation results with high repeatability. The at least one cohesive joint can be configured, for example, as a cohesive hinge, for example as a film hinge. The at least one displaceable contact element may be formed, for example, as an axial spacer, which is arranged in the assembled state positive and / or non-positive between the connecting piece and the encoder housing of the rotary encoder to ensure a defined axial distance. The displacement of the contact element may include a radial disengagement of the contact element. In this way, about a form-locking position assurance of the position assurance element can be canceled on the encoder system. The position assurance element can be solved in a simple manner without the need for a tool. In this way, the rotary encoder system can be put in an operable state in which the connector can unfold its tolerance-compensating function.

Preferably, at least two axial spacers are provided in a position securing element, which lie substantially opposite one another. In this way, on the one hand in the assembled state, a secure positive connection for the position assurance element can be provided. On the other hand, the disengagement of both spacers, which can be effected for example by a "compression" of two substantially opposite handling sections, can contribute in a simple manner to the release of the position securing element.

In a preferred development, at least one lateral limb of the position securing element has a tilting region about which at least one partial tilt of the limb can take place when the at least one handling section is actuated in the joined state.

The lateral leg can be designed as rocker similar. The tilting area can be formed for example by a tilting edge or tilting surface, which provides a deflection point for the leg. Tilting of the leg can be triggered by actuation of the handling section. In other words, the handling portion can be displaced in the direction of the (imaginary) longitudinal axis, whereby a further portion of the leg, on which in particular at least one axial spacer is arranged, can be moved away from the longitudinal axis. In this way, the axial spacer can disengage from the composite with the rotary encoder and the connector.

According to a further embodiment, the position assurance element further comprises a manipulation indicator, which is activated in particular when releasing the position assurance element from the joined state. The manipulation indicator (or: manipulation detector) may be used, for example, to make unauthorized multiple use of the position assurance element difficult or impossible. The manipulation indicator may be, for example, a predetermined breaking point in the position securing element, which is damaged or destroyed during actuation of the at least one handling section for releasing the position securing element.

According to a further preferred embodiment, the position assurance element has an integrated, one-piece design, wherein the position assurance element is in particular made of a plastic material or a sheet metal material. In this way, the position assurance element can be made highly automated, cheap and easy. The position assurance element can thus be particularly suitable for a single use. In particular, the position assurance element can be attached to the encoder system, for example, by the manufacturer. In this way, the rotary encoder system can already be placed in the assembled state during manufacture, in which the rotary encoder and the connecting piece are fixed together in a preferred position. In this way, for example, excessive stress or damage during transport, storage and during subsequent assembly can be avoided.

The object of the invention is further achieved by a rotary encoder system for detecting revolutions of a measuring shaft of a measured object to be monitored, with a rotary encoder, with a tolerance-compensating connector for attaching the encoder to the device under test, wherein the encoder has a transmitter housing with a transmitter unit, wherein in the encoder housing a Encoder shaft is mounted, which is connected to the measuring shaft substantially rigidly to the rotational drive, preferably with determination of an axial position assignment between the encoder shaft and the measuring shaft, and wherein the encoder system is provided in particular for assembly purposes with a releasable position assurance element according to one of the aforementioned aspects, in a joined state determines the encoder housing and the connector in a relative position to each other.

Also in this way the object of the invention is completely solved.

The housing part may be, for example, an integral part of a housing of the test object. However, the housing part can also be an adapter piece which is connected to the housing of the test object. In particular, the housing part may be configured as cup-shaped, cup-shaped or as a so-called end shield. In this way, the housing part on the one hand provide some protection for the encoder system. On the other hand, certain installation space restrictions may result for the installation of the rotary encoder system. Using the position-securing element, the encoder system can be safely and easily mounted even under difficult installation conditions. In particular, potentially disadvantageous biases in the connection piece can be avoided.

The position assurance element can act as a position assurance, but also about as a transport lock. The position securing element makes it possible to design the connecting piece such that it can be arranged as space-saving as possible between the encoder housing and the housing part of the test object. In particular, little consideration needs to be given to the mountability of the encoder system when designing the fitting. The position assurance element can contribute to the fact that the rotary encoder can be received in a neutral position on the measurement object essentially "load-free".

The object of the invention is further characterized by a measuring system with a measuring object and with a rotary encoder system according to one of the aforementioned Aspects solved, wherein the encoder system is flanged using the position assurance element to the measurement object.

With regard to the method, the object of the invention is achieved by a method according to the independent method claim.

Also in this way the object of the invention is completely solved. By applying the method, in particular, a disadvantage can be avoided, which results from the design-related flexibility of the combination of shaft encoder and connector. The connection piece is usually designed to act in a tolerance-compensating manner. However, this functionality may be detrimental to the assembly of the encoder system. For example, it can lead to preload in the connector, which affect the rotary encoder when mounted. In this way, for example, the life of the encoder can be reduced.

The position assurance element may in particular be selected according to one of the aforementioned aspects. The joining steps may in particular include indirect joining and / or direct joining.

The method can be further developed in that the joining of the connection piece comprises an insertion of at least one arm of the connection piece into a guide geometry, in particular at least one recess, which is formed on the housing part of the measurement object, and in that the release of the position securing element comprises a tool-free release, the In particular, an actuation of handling sections, which are formed on legs of the position assurance element.

In this way, the position assurance element can be solved by a simple radial pressure on the handling sections without tools from the encoder system. As a result of the radial pressure, contact elements of the position-securing element can be brought out of engagement with the connection piece and the encoder housing. The engagement of the position-securing element can take place in a non-positive and / or form-fitting manner. A positive engagement may include, for example, an undercut embracing the encoder by the position assurance element.

It is understood that the features of the invention mentioned above and those yet to be explained below can be used not only in the particular combination indicated, but also in other combinations or in isolation, without departing from the scope of the present invention.

Further features and advantages of the invention will become apparent from the following description of several preferred embodiments with reference to the drawings. Show it:

1 a partially sectioned side view of a measuring system having a measuring object and a rotary encoder system;

2 a perspective rear view of another measuring system with a modified encoder system;

3 a side view of a position assurance element;

4 an enlarged partial perspective view of a rotary encoder system with a mounted position securing element, which defines a rotary encoder and a connector in a relative position to each other;

5a an enlarged side detail view of a connector in the region of a boom;

5b another view of the boom in an orientation that in 5a is indicated by Vb;

5c another view of the boom in an orientation that in 5a indicated by Vc;

6 a side section through another measuring system having a measuring object and a rotary encoder system with a position assurance element;

7 a perspective front view of another encoder system, which is approximately with the in 6 shown encoder system can correspond;

8th a perspective rear view of the measuring system according to 6 ; and

9 An embodiment of a method for attaching a rotary encoder system to a measured object.

1 shows a partially sectioned side view of a measuring system, the total with 10 is designated. The measuring system 10 has a measurement object 12 and a rotary encoder system 14 on. The encoder system 14 can be used for detecting rotational movements, rotational speeds, Rotation angles, rotational accelerations or decelerations and derived therefrom can be used. Often, there is a desire to acquire the desired measured values with high precision. For this reason, in rotary encoder systems 14 Often special design measures required to achieve the most accurate coupling of the encoder system 14 to the measurement object 12 to be able to guarantee.

The encoder system 14 has a rotary encoder 16 as well as a connection piece 18 on. The connection piece 18 may also be referred to as a coupling piece or generally as a housing coupling. The connection piece 18 may be adapted to the rotary encoder 16 , in particular a rotary encoder housing, on a housing part 20 of the measurement object 12 set. The housing part 20 can be an integral part of a housing of the DUT 12 be. The housing part 20 can in particular flange on the measurement object 12 be educated. In the case part 20 It can also be a separate part, that on the measurement object 12 can be fixed. The housing part 20 can be used as a frame-fixed component of the test object 12 be executed.

In 1 is also by means of dashed lines a position assurance element 50 indicated, especially in the assembly of the encoder system 14 can be beneficial. Exemplary embodiments of the position assurance element 50 are described below, cf. in particular also 3 . 6 and 7 ,

At the encoder 16 can be a transmitter unit 22 be formed, which is provided for approximately absolute and / or relative rotations. The transmitter unit 22 of the rotary encoder 16 can be accommodated in particular in a transmitter housing, compare about a donor housing 42 in 2 , The encoder 16 also usually has a transmitter shaft 24 on, as possible torsionally stiff with a measuring shaft 26 of the measurement object 12 can be coupled. Twists of the measuring shaft 26 can on the encoder shaft 24 be transferred and through the encoder unit 22 be recorded.

At the measuring shaft 26 it can be about a motor shaft or a gear shaft. At the measuring object 12 it can be about a motor or a gear. The measurement object 12 However, it can also be part of an engine or a transmission. Other applications for encoder systems 14 are conceivable without further notice. The measuring shaft 26 can be around a longitudinal axis 28 be designed rotatable or pivotable, compare one with 30 designated double arrow. In real use can be on the measuring shaft 26 Deformations or displacements occur. These can be caused by static or dynamic loads. Furthermore, displacements may result from manufacturing tolerances. It must be expected that the measuring shaft 26 is subject to deformation or displacement during operation or even at a standstill. These can occur constantly or dynamically.

For a highly accurate detection of rotational movements of the measuring shaft 26 can be provided, it can be provided, the encoder shaft 24 highly rigid with the measuring shaft 26 connect to. This can be exemplified by a conical connection 34 between the encoder shaft 24 and the measuring shaft 26 to offer. A conical shaft connection can be designed and executed in such a way that there is no or almost no relative movement between the encoder shaft 24 and the measuring shaft 26 occurs. The conical shaft connection 34 can be exemplified by a fastener 36 be secured. In the fastener 36 it can be about a screw, the encoder shaft 24 protrudes and with a thread of the measuring shaft 26 is coupled. Other types of connection or types of attachment between the encoder shaft 24 and the measuring shaft 26 are conceivable.

The encoder system 14 can the measured object 12 be fed along a longitudinal direction or feed direction, which by a with 32 indicated arrow is indicated. It is advantageous if the encoder 16 a rear recess 38 has, by about the fastener 36 can be supplied or at least operated. Under a rear side of the rotary encoder 16 can be understood as the side that in the assembled state of the measured object 12 turned away. Accordingly, the term front side or frontal side that side of the encoder system 14 , the rotary encoder 16 or their components are understood, in the mounted state of the measured object 12 is facing.

Especially if the encoder shaft 24 and the measuring shaft 26 high-strength connected to each other, such as by means of the conical shaft connection 34 , Both a determination of a rotational position (rotation about the longitudinal axis 28 ) As well as a determination of an axial position (axial position on the longitudinal axis 28 ) respectively. According to some embodiments, the rotary encoder 16 therefore already statically determined on the housing part 20 of the measurement object 12 be included when the connector 18 only an anti-twist device for the encoder housing 42 ( 2 ) of the rotary encoder 16 provides.

The highly rigid coupling between the encoder shaft 24 and the measuring shaft 26 causes all displacements or deformations, the at the measuring shaft 26 occur, directly and without significant decoupling on the encoder shaft 24 can be transmitted. So the encoder shaft 26 have an axial offset and / or a radial offset. Furthermore, the encoder shaft 26 opposite to an (imaginary) ideal position of the longitudinal axis 28 may be inclined and / or at least partially have a curvature. Would be in such a case, the encoder 16 (or the encoder housing 42 ) highly rigid and relentless on the housing part 20 it could be fixed in the encoder 16 come to excessive component loads. This could result in a reduced lifetime and increased wear of the encoder unit 22 knock down.

It is therefore an object of the fitting 18 , the rotary encoder 16 on the one hand against a relative rotation with respect to the housing part 20 to secure. Here, the highest possible torsional rigidity is sought. On the other hand comes the connector 18 the task to be as tolerant as possible and compliant in other spatial directions. In this way it should be made possible that the rotary encoder 16 total deformation-related and / or displacement-related movements of the measuring shaft 26 can understand. In this way, excessive loads on the transmitter unit 22 be avoided. The measuring accuracy and the life of the rotary encoder 16 can be improved.

An exemplary design of a rotary encoder system with a connector that at least approximately fulfills the aforementioned requirements, is in the not pre-published German utility model application (file number 20 2011 108 029.1 ) of the applicant. 2 shows a perspective rear view of a measuring system 10a That with a rotary encoder system 14 is provided, which may have a basically similar structure. The encoder system 14 with the rotary encoder 16 and the fitting 18 is in a cup-shaped or pot-shaped housing part 20 introduced. In the housing part 20 is at least one recess 44 provided, which may be configured as a guide, in particular as a longitudinal groove. In the recess 44 is a boom 46 of the connector 18 taken with the case 42 of the rotary encoder 16 is coupled. It is understood that as well a plurality of recesses 44 on the circumference of the housing part 20 may be provided, in which a plurality of cantilevers 46 of the connector 18 can be introduced. By way of example, approximately two recesses each 44 and outriggers 46 be provided. The recess 44 can be designed such that the boom 46 can not reach the system axially in a desired position. As already mentioned above, it is preferred if the axial orientation of the rotary encoder 16 through the coupling of the encoder shaft 24 with the measuring shaft 26 done, compare 1 , In other words, the encoder 16 "Floating" in the housing part 20 be included. This results in an excellent suitability for tolerance compensation. At the rear end of the rotary encoder 16 is also with 48 a connecting line indicated in 2 however, only partially shown.

It is often desirable to have the encoder system 14 using only the smallest possible space with the object to be measured 12 to pair. This can lead to the assembly of the encoder system 14 cramped space prevail. To make matters worse, that encoder systems 14 often on hard-to-reach positions on DUTs 12 are to be attached. When mounting the encoder system 14 Care should be taken, if possible, no bias on the encoder 16 or the connector 18 to create. The bias could be particularly disadvantageous to bearing the encoder unit 22 impact. It should therefore be striven in principle, the encoder system 14 mount in such a way that at rest (standstill of the measuring shaft 26 ) the rotary encoder 16 recorded as free of load.

The connection piece 18 is however in the mounted state between the measuring object 12 and the encoder 16 In addition, and can almost completely from the housing part 20 be covered. An operator (or fitter) can use the fitting 18 when inserting the encoder system 14 in the housing part 20 lead and control hardly or only with great effort. There is a possibility that the connector 18 is received in the assembled state in a position in which it is biased unfavorably. On the one hand, this can lead to a load on the shaft encoder already in the idle state 16 acts. Furthermore, by the bias the possibility of the connector 18 be limited to tolerance compensation.

Below, various approaches are presented, such as the encoder system 14 can be installed quickly and with high precision without great effort and without the need for special tools in a simple manner. In particular, a mounting of the encoder system 14 such that the connection piece 18 after mounting without preload or almost without preload on the housing part 20 is included.

3 shows a side view of a position assurance element 50 , especially for assembly purposes with the encoder system 14 can be coupled. The position assurance element 50 can about to be referred to as a mounting auxiliary element. The position assurance element 50 is in 3 presented in isolation. One with the in 3 shown view in a mounted (or: joined) state can 6 be removed. The position assurance element 50 may be designed in particular bow-shaped or handle-shaped. The position assurance element 50 can in its rear area (compare the arrow 32 ) One Base 52 exhibit. To the base 52 At least one leg can be 54 connect. This in 3 illustrated position securing element 50 has two legs 54a . 54b on. It may thus result in a U-shaped design. It is readily conceivable, the position assurance element 50 with a plurality of thighs 54 to provide. In particular, it may result in a spider-like or krakenartige design. The number of thighs 54 can with the number of outriggers 46 of the connector 18 and / or with the number of recesses 44 (also: guide grooves) in the housing part 20 of the measurement object 12 correspond.

In a fitted state, when the position assurance element 50 with the rotary encoder 16 and the fitting 18 coupled, the base may be 52 in a rear area of the rotary encoder 16 be arranged. The thigh 54 can be starting from the base 52 approximately parallel to the longitudinal axis 28 ( 1 ) or to the longitudinal direction 32 extend. At her base 52 the opposite end can be the legs 54 contact elements 56 have, which are adapted to, in the assembled state, the rotary encoder 16 and / or the fitting 18 to contact. In this way, the encoder can 16 and the connector 18 be fixed to each other in a defined relative position. The installation of the encoder system 14 can be significantly simplified and done with higher accuracy.

At the contact elements 56 it can be an example of spacers 60 . 62 act. In synopsis of 3 and 4 is an exemplary design of the spacers 60 . 62 described. An axial spacer is denoted by the reference numeral 60 designated. The axial spacer 60 can be a desired axial distance between the encoder 16 and the fitting 18 define, in particular, the detailed view in 4 , A resulting distance measure can be denoted approximately by a. The axial spacer 60 can the encoder 16 surround undercut. One with the reference numeral 62 designated spacer may be a radial distance between the encoder 16 and the fitting 18 define. The radial distance can be referred to as e. The radial spacer 62 can help the encoder 16 and the connector 18 align as concentrically as possible during assembly. Together, the spacers can 60 . 62 help to make the encoder and 16 the connector 18 aligned with a sufficiently high accuracy. Also a tilt between the connector 18 and the encoder 16 can be avoided as far as possible.

It is understood that the position assurance element 50 not only during assembly of the encoder system 14 can be beneficial. The position assurance element 50 may also allow a desired relative position between the encoder 16 and the connector 18 already during production, transport and / or storage.

It is further understood that both spacers 60 . 62 on a thigh 54 can be trained. It is also conceivable, at least some of the legs 54 with the spacer 60 to provide and at least some more of the thighs 54 with the spacer 62 to provide. The spacer 62 can be exemplified by two bars 64 . 66 be formed, which are offset radially to each other. By way of example, the bridge 64 be sufficiently rigid, whereas the bridge 66 can be designed deformable. As a result, the bridge can 64 much thicker than the bridge 66 be designed. The jetty 66 can be used as a tapered continuation of the thigh 54 be educated. The jetty 64 can over the thigh 54 be offset radially inward. The term "offset inwards" can be understood to mean an offset that is in the assembled state of the position-securing element 50 radially in the direction of the longitudinal axis 28 done, compare 1 , The jetty 64 can via connecting ribs 68 . 70 with the thigh 54 or the bridge 66 be connected. At the jetty 64 can be a contact surface 72 be formed in the joined state, the encoder housing 42 of the rotary encoder 16 contacted. In this context shows 4 a further advantageous embodiment of the position assurance element 50 in which the contact surface 72 is significantly increased. For this purpose, at the jetty 64 about a lateral contact arm 84 be educated. Preferably, at the dock 64 two substantially symmetrical contact arms 84 educated. The contact arms 84 can the housing 42 at least partially peripherally contact and thus ensure good leadership.

At least one of the bridges 54 may be a handling section 74 be educated. In 3 is an example on the jetty 54a a handling section 74a trained while at the jetty 54b a handling section 74b is provided. The handling sections 74 can be structured. By way of example, the handling sections 74 be provided with a corrugation or knurling. The handling sections 74 can be provided with elevations or depressions. The handling sections 74 can be operated by an operator to the position assurance element 50 from the assembled state with the fitting 18 and the encoder 16 to solve. About the handling sections 74 For example, the operator may apply a force that helps to secure the position assurance element 50 defined to deform. The deformation may be, for example, the first spacer 60 out of engagement with the fitting 18 and the encoder 16 disengage, to a positive position assurance of the position assurance element 50 to overcome. In particular, in synopsis of 4 and 6 it will be apparent that the position assurance element 50 in the assembled state positive fit on the encoder system 14 can be included. In particular, at least one spacer 60 can the encoder 16 embrace the front. The area in which the spacer 60 is arranged, however, after the assembly of the encoder system 14 hardly or not at all can be reached from the outside. For this reason, it is preferably provided, the position assurance element 50 such that the spacer or spacers 60 by an inward pressure (compare with 76a . 76b designated arrows in 3 ) on the handling sections 74a . 74b can be disengaged. Subsequently, the position assurance element 50 against the longitudinal direction 32 from the encoder system 14 subtracted from.

According to one embodiment, the disengagement of the spacers 60 caused by the legs 54a . 54b tiltable designed. On the thighs 54 can be a so-called tilting area 78 be educated. The tilting area 78 can be formed by an edge. The tilting area 78 can in particular by a terminal edge of the contact surface 72 be formed. An inward action on the handling sections 74a . 74b can be a tilting of the thighs 54a . 54b around the tilting areas 78 cause. The handling sections 74a . 74b can be inward (in the direction of the longitudinal axis 28 ) are relocated. The distance between the handling sections 74a . 74b can decrease. The spacers 60 can be shifted to the outside. A distance between the spacers 60 can increase.

In 4 illustrates one with 79 designated arrow the disengagement of the spacer 60 , It is further apparent that the jetty 66 in the assembled state radially on the boom 46 of the connector 18 can be present. A tilt of the associated leg 54 of the position assurance element 50 can lead to deformation of the web 66 to lead. In this context, it is beneficial to the jetty 66 thin-walled to perform the disengagement of the spacer 60 to facilitate. When activating or actuating the handling sections 74a . 74b also learns the basis 52 of the position assurance element 50 a deformation. The base 52 can in the in 3 view shown to have a bent course. In this way results in the operation of the handling sections 74a . 74b for the deformation of the base 52 a preferred direction. The deformability of the base 52 can also be simplified in that at least one so-called fabric joint 80 is trained. The fabric joint 80 may generally designate a section or area in which the wall thickness of the position assurance element 50 is deliberately reduced to increase the ductility. The fabric joint 80 can exemplarily center at the base 52 be educated. In this area can the base 52 furthermore a recess 82 exhibit. The recess 82 may in particular serve as a mounting opening to the fastener 36 from the outside for a tool, see also 6 , It goes without saying, however, that the base 52 also be designed differently. It is further understood that upon actuation of the handling sections 74a . 74b large areas of the position assurance element 50 contribute to its deformation. In particular, the deformation is not limited to explicitly provided fabric joints 80 limited.

In synopsis of 4 . 5a . 5b and 5c is an exemplary design of a boom 46 of the connector 18 illustrated. It can be a plurality of outriggers 46 at the connection piece 18 be provided. The boom 46 puts on the connector 18 essentially the coupling geometry ready, in the joined state, the contact elements 56 of the position assurance element 50 contacted. The boom 46 can basically be designed as a radial arm. The boom 46 can have a stepped design, compare one with 86 designated set piece in 4 , The boom 46 can serve on the one hand, the position assurance element 50 to contact. The boom 46 However, also can be used to the recess 44 (also: guide groove) in the housing part 20 of the measurement object 12 to contact, compare 2 , In the 5a . 5b and 5c is the boom 46 shown in isolation. The boom 46 can be next to the set piece 86 a base strap 88 have, to which an outer flap 90 followed. Together, the set piece 86 , the basic strap 88 and the outer flap 90 have a stepped or stepped structure. The set piece 86 may face a base of the fitting 18 be angled. The base strap 88 can be compared to the set piece 86 be angled. The outer flap 90 can be compared to the base strap 90 be angled. The bends or bends can each have a bending angle of about 90 °.

The outer flap 90 can be used as an outer radial stop for the spacer 62 serve. The outer flap 90 especially through the bridge 66 be contacted. At one with the operation of the handling sections 74a . 74b accompanying disengagement of the spacer 60 Also acts a radially outward force on the bridge 66 , The jetty 66 However, the outer strap can 90 do not overcome. The jetty 66 may deform to disengage the spacer 60 due to a tilting or pivoting movement of the leg 54 to allow.

At the outer flap 90 can at least one side flap 92 be educated. On the basis of in 5b shown view that two basically symmetrical side flaps 92 are conceivable. Together, the outer flap 90 and the side flaps 92 have a U-shaped cross section. The side flaps 92 can be starting from the outer flap 90 extend substantially radially inward. The side flaps 92 may be formed to sidewalls of the guide groove or recess 44 in the housing part 20 to contact. For this purpose, an outer width of the side flaps 92 be adapted to a groove width. An inscribed with b inner width of the side flaps 92 can with a width of the spacers 60 . 62 or the thigh 54 of the position assurance element 50 correspond. In this way, the boom can 46 the encoder 16 essentially without a backlash in the recess 44 establish. Furthermore, the boom 46 in the assembled state a rotational position for the position assurance element 50 define.

In synopsis with the 5b and 5c will also be apparent that in particular on the side flaps 92 arched end areas 94 . 96 can be provided. The arched end areas 94 . 96 can provide improved guidance and mountability for the boom 46 in the recess 44 guarantee. Especially the end areas 96 at the end of the side flaps 92 are formed, in the mounted state of the measured object 12 facing, can be an insertion of the boom 46 into the recess 44 simplify.

7 shows a perspective view of a rotary encoder system 14 where the front is visible. The encoder system 14 is with the encoder 16 and the fitting 18 provided, further wherein the position assurance element 50 in the joined state with both components 16 . 18 is coupled. The position assurance element 50 can start from the rear side via the rotary encoder 16 be slipped and in the area between the encoder 16 and the fitting 18 snap in, compare too 4 , The in 7 shown state of the encoder system 14 can correspond to a delivery state or mounting state. In 6 is the rear side of the rotary encoder 16 through one with 98 indicated arrow marked.

The connection piece 18 has two outriggers 46a . 46b on, each with a thigh 54 of the position assurance element 50 are coupled. The connection piece 18 also has at least one mounting bracket 102 on top, with a mounting surface 104 coupled, which is about the encoder housing 42 of the rotary encoder 16 is trained. It is understood that the connector 18 about two mounting arms 102 may in particular be opposite each other. A plurality of mounting brackets 102 is conceivable. The mounting bracket 102 can safely by means of a screw on the mounting surface 104 be set. The mounting bracket 102 can basically on a peripheral surface of the encoder 16 be fixed, compare 7 , Alternatively, the boom 102 However, also on an end face (or: frontal surface) of the encoder 16 be fixed, the unmounted state of the measured object 12 is facing.

The in 7 exemplified state of delivery of the encoder 14 allows mounting essentially without special tools. Preferably, only a tool for fastening the fastener 36 at the measuring shaft 26 required, see also 1 ,

8th shows a perspective view of a rotary encoder system 14 that about with the in 7 shown encoder system can correspond. The encoder system 14 is on a cup-shaped housing part 20 a measurement object 12 added. The encoder system 14 is at least partially in the housing part 20 sunk. This is the encoder system 14 well protected against environmental influences and damage. Using the location backup item 50 can the encoder system 14 even in confined space conditions safe and easy to be mounted. Especially if the encoder shaft 24 and the measuring shaft 26 are firmly connected to each other, the position assurance element 50 from the combination with the encoder system 14 be solved. The release of the position assurance element 50 can be done without tools in a preferred embodiment. It may in particular satisfy the handling section or sections 74 to press. An actuation of the handling sections 74 may be a deformation or displacement of the position assurance element 50 cause the disengagement of contact elements 56 can cause comparisons 3 , After loosening the contact elements 56 can be the location backup element 50 easy from the encoder system 14 be deducted, compare one with 106 designated arrow.

Preferably, the position assurance element 50 as a plastic part, in particular as a molded plastic part formed. In this way, the position assurance element 50 inexpensive to produce. The position assurance element 50 can in principle be suitable for single use. This can include any encoder system 14 in the delivery state with a position securing element 50 is provided. In this way, the desired relative position between the connector 18 and the encoder 16 even during transport or storage. It is understood that in principle also a multiple use of the position assurance element 50 is conceivable. Alternatively, the position assurance element 50 be made of a sheet material by combining suitable separation processes and forming processes. Nevertheless, the design is preferred as a plastic component. In this context, it should be noted that in the manufacture or manufacture of the position assurance element 50 in the first place, the distances a and e are relevant, cf. 3 , However, these are relatively small dimensions that can be made in the plastic production, such as injection molding, without significant effort with reasonable tight tolerances. Apart from that, the position assurance element 50 be manufactured with relatively large tolerances that do not affect the functionality. Overall, the position assurance element 50 be produced inexpensively by means of plastic injection, without the need for significant rework.

The position assurance element 50 may have a tamper-resistant, which makes it difficult to unauthorized reuse or completely prevented. Once solved position securing element 50 in particular, can not easily re-connect to the encoder system 14 get connected. In this connection will be on again 6 directed. If the position securing element is slipped over 50 in the direction of the arrow 32 would initially be a widening of the thighs 54a . 54b be required to stand between the spacers 60 ( 3 ) to provide a necessary clearance. However, this would cause the jetty 66 not in through the outer flap 90 can thread the provided space. An unauthorized installation of the position assurance element 50 would be much more difficult or even completely prevented.

Based on 9 is an exemplary embodiment of a method for mounting or mounting a rotary encoder system 14 on a test object 12 explained.

In a first step S10, a rotary encoder system 14 be provided, which is a position assurance element 50 having. The encoder system 14 especially with one of the encoder systems 14 correspond to one of the aforementioned aspects. The encoder system 14 in particular, a rotary encoder 16 and a connector 18 for mounting the rotary encoder 16 on a test object 12 exhibit. Advantageously, a position securing element 50 provided that the rotary encoder 16 and the connector 18 in a relative position determines each other. In this way, the assembly of the encoder system 14 almost or entirely without the generation of adverse bias.

In a next step S12, the encoder system 14 a measuring object 12 be supplied. It may follow further steps S14, S16, which can be carried out in principle at the same time or in any order. A step S14 may be the joining of the fitting 18 with a housing part 20 of the measurement object 12 include. A step S16 may be the joining of a transmitter shaft 24 of the rotary encoder 16 with a measuring shaft 26 of the measurement object 12 include. The step S16 may further in particular the torsionally rigid or rotationally fixed fixing of the encoder shaft 24 and the measuring shaft 26 include.

It may be followed by a step S18, in which the position assurance element 50 is solved to a defined relative movement between the encoder 16 and the fitting 18 to allow. In this way, the encoder system can 14 a high suitability for tolerance compensation arise, in particular on positional deviations and deformations of the measuring shaft 26 refers.

Claims (13)

Position securing element ( 50 ) for a rotary encoder system ( 14 ), the encoder system ( 14 ) a rotary encoder ( 16 ) and a tolerance compensating fitting ( 18 ) and for detecting revolutions of a measuring shaft ( 26 ) of a measured object to be monitored ( 12 ), wherein the position assurance element ( 50 ) detachable with a transmitter housing ( 42 ) of the rotary encoder ( 16 ) and the connector ( 18 ) and is adapted, in a joined state, the encoder housing ( 42 ) and the connector ( 18 ) in a relative position to each other, wherein the position assurance element ( 50 ) with a base ( 52 ) is provided, from which at least one lateral leg ( 54 ), wherein on at least one leg ( 54 ) Contact elements ( 56 ) are formed, which in the assembled state, the encoder housing ( 42 ) and the connector ( 18 ), wherein the contact elements ( 56 ) axial spacers ( 60 ) and radial spacers ( 62 ), wherein the position assurance element ( 50 ) a bow-shaped or a spider-like design with a plurality of lateral thighs ( 54 ) starting from the base ( 52 ), and wherein the position assurance element ( 50 ) the encoder housing ( 42 ) can engage around from its rear side, which the connecting piece ( 18 ) is turned away. Position securing element ( 50 ) according to claim 1, wherein the base ( 52 ) in the assembled state from the encoder housing ( 42 ) is spaced. Position securing element ( 50 ) according to any one of the preceding claims, wherein the base ( 52 ) a recess ( 82 ), which is arranged in particular centrally. Position securing element ( 50 ) according to one of the preceding claims, wherein at least one lateral limb ( 54 ) a handling section ( 74 ), which in particular has a structuring, wherein the handling section ( 74 ) at a base end of the leg ( 54 ) is provided. Position securing element ( 50 ) according to one of the preceding claims, comprising at least two handling sections ( 74 ), in particular on opposite thighs ( 54 ), wherein a radial pressure on the handling sections ( 74 ) in the joined state, a defined deformation of the position assurance element ( 50 ) causes. Position securing element ( 50 ) according to one of claims 4 or 5, further comprising at least one cohesive joint ( 82 ), which at least in the joined state by a pressure on the at least one handling section ( 74 ) is deformable such that at least one contact element, in particular an axial spacer, is displaced to the position securing element ( 50 ) can be detached from the assembled state without tools. Position securing element ( 50 ) according to one of claims 4 to 6, wherein at least one lateral limb ( 54 ) a tilting area ( 78 ), to the at least a partial tilting of the leg ( 54 ) can take place when the at least one handling section ( 74 ) is actuated in the joined state. Position securing element ( 50 ) according to one of the preceding claims, further comprising a manipulation indicator which, in particular when releasing the position-securing element ( 50 ) is activated from the joined state. Position securing element ( 50 ) according to one of the preceding claims, comprising an integrated, one-piece design, wherein the position assurance element ( 50 ) is made in particular of a plastic material or a sheet metal material. Encoder system ( 14 ) for detecting revolutions of a measuring shaft ( 26 ) of a measured object to be monitored ( 12 ), with a rotary encoder ( 16 ), with a tolerance compensating fitting ( 18 ) for mounting the rotary encoder ( 16 ) on the test object ( 12 ), whereby the encoder ( 16 ) an encoder housing ( 42 ) with a transmitter unit ( 22 ), wherein in the encoder housing ( 42 ) a sensor shaft ( 24 ) which is connected to the measuring shaft ( 26 ) is rigidly connected to the rotary driving, and wherein the encoder system ( 14 ) with a detachable position securing element ( 50 ) according to one of the preceding claims, which in an assembled state, the encoder housing ( 42 ) and the connector ( 18 ) in a relative position determines each other. Measuring system ( 10 ) with a measuring object ( 12 ) and with a rotary encoder system ( 14 ) according to claim 11, wherein the rotary encoder system ( 14 ) to the measurement object ( 12 ) is flanged. Method for fastening a rotary encoder system ( 14 ) on a measurement object ( 12 ), the encoder system ( 14 ) for detecting revolutions of a measuring shaft ( 26 ) of the test object ( 12 ), comprising the following steps: - providing a rotary encoder system ( 14 ) according to claim 10, - supplying the rotary encoder system ( 14 ) to the measuring shaft ( 26 ) of the test object ( 12 ), - joining the connector ( 18 ) of the rotary encoder system ( 14 ) with a housing part of the test object ( 12 ), - adding a encoder shaft of the rotary encoder ( 16 ) with the measuring shaft ( 26 ) of the test object ( 12 ), and - after the step of joining the rotary encoder ( 16 ) with the measuring shaft ( 26 ), tool-free release of the position-securing element ( 50 ), a compensation movement between the rotary encoder ( 16 ) and the connector ( 18 ) to allow. The method of claim 12, wherein the joining of the fitting ( 18 ) introducing at least one arm of the connecting piece ( 18 ) in a guide geometry, in particular at least one recess ( 44 ), which on the housing part ( 20 ) of the test object ( 12 ), and wherein the release of the position assurance element ( 50 ) an actuation of handling sections ( 74 ), which are attached to thighs ( 54 ) of the position assurance element ( 50 ) are formed.

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