DE102014102564B4 - Absolute single-turn rotary encoder with selectable multiturn function - Google Patents

Abstract

Absolute value single-turn rotary encoder (10) with selectable multi-turn function comprising: an electronic angle sensor (14) and an electronic evaluation unit (16); anda closed housing (12) into which the angle sensor (14) and the evaluation unit (16) are integrated and which has an external physical interface (18) for coupling an external attachment (26), the interface (18) for positive engagement wherein the evaluation unit (16) is arranged to be operated both in a single-turn configuration and in a multi-turn configuration, wherein the evaluation unit (16) is further configured to: recognize whether the add-on (26) is coupled to the interface (18) automatically to switch from singleturn configuration to multiturn configuration without further configuration as soon as it is detected that the add-on (26) is docked; and to remain in the singleturn configuration when the attachment (26) is not coupled to the interface (18).

Description

Absolute single-turn rotary encoder with selectable multiturn function

The present invention relates to an absolute value singleturn rotary encoder with additionally selectable multiturn function.

The DE 198 49 108 A1 discloses a rotary encoder. The EP 0 550 794 B1 discloses a rotary encoder with an absolute position detection. The EP 0 516 572 B1 discloses a method for pseudo-absolute determination of the angle of a shaft and an autonomous sensor for carrying out this method. The item "An integrated single output signal encoder for both multi-turn absolute encoder use and incremental encoder use" (Takashi Katagiri et al., Industry Applications Society Annual Meeting, 1994, Conference Record of the 1994 IEEE, Volume 1, pages 347-351, 2 until October 6, 1994) discloses a signal generator. The WO 2010/121595 A2 discloses a gearless rotary encoder. The DE 10 2008 055 687 A1 discloses a miniaturized battery-powered rotary encoder.

There are rotary encoders for detecting angular positions of a encoder shaft within 360 ° (single-turn encoders) as well as rotary encoders, which are additionally equipped with a device to detect rotation angles larger than 360 ° (multi-turn encoders). Multiturn encoders can be operated both under operating voltage and in an operating voltage-free state (see eg DE 198 49 108 A1 ) operate. The above-mentioned additional facilities may, for. B. can be realized by: mechanical counters, which are read out by means of a suitable sensor (optical, magnetic, inductive, etc.) electronically (see, eg EP 0 550 794 B1 ); or electronic counters (see eg EP 0 516 572 B1 ), which usually consist of a sensor element for detecting the rotation, an electronic calculator (processor, ASIC, VPGA, etc.), an electronic memory and a power source (primary or secondary battery, capacitor, energy harvester, etc.) wherein the sensor element may be the same sensor which also serves to detect the position within 360 ° (single-turn sensor).

A multi-turn encoder is therefore technically more complex than a single-turn encoder. Multi-turn encoders are always more expensive than pure single-turn encoders, because to detect several (complete) revolutions always the additional facilities are required, which lead to the manufacturer of the encoder to a greater effort compared to single-turn encoders. Therefore, singleturn encoders and multiturn encoders are now offered separately and in parallel.

A user or dealer who requires both a single-turn and a multi-turn encoder is thus forced to procure and store both types of encoders, which entails increased costs. Alternatively, a configurable multiturn rotary encoder can be used, which can be downconverted to a single-turn rotary encoder. This multiturn encoder is more expensive than comparable single-turn encoders.

For the manufacturers of encoders, it would be advantageous if the manufacturers had to provide only a single encoder type, which can be configured as needed to a single-turn or multi-turn encoder. The configuration should preferably be carried out by the (end) customer without, however, having to carry out complex and complicated configuration steps.

This object is achieved by a rotary encoder according to claim 1.

There is disclosed an absolute single turn rotary encoder with selectable multi-turn function comprising: an electronic angle sensor and an electronic evaluation unit; and a closed housing in which the angle sensor and the evaluation unit, preferably inaccessible from the outside, are integrated and which has an external physical interface for coupling an external attachment element; wherein the evaluation unit is arranged to operate both in a single-turn configuration and in a multi-turn configuration; characterized in that the evaluation unit is further configured to: recognize whether the attachment is coupled to the interface; automatically switch from the singleturn configuration to the multiturn configuration without any further configuration measures, as soon as it has been detected that the attachment is coupled; and to remain in the singleturn configuration if the attachment is not coupled to the interface. The interface is set up for positive reception of the external power supply unit in the housing.

In the rotary encoder of the invention required for generating the multi-turn function components or add-on elements from the end user simply the originally designed as a single-turn encoder encoders can be additionally attached to the originally designed as a single-turn encoder encoders during assembly or in the application, almost in the last second, in addition to provide a multi-turn functionality. The end user, who uses both singleturn and multiturn encoders, thus only has to stock singleturn encoders with a comparatively low-cost multiturn attachment automatically reconfigurable by physically coupling the add-on to the singleturn encoder.

It is economical to carry out a determination of the rotary encoder to a specific characteristic (on singleturn or multiturn) as late as possible in a production process. In this way, a logistics and storage costs can be kept low. The switching of a rotary encoder from a single-turn functionality to a multi-turn functionality is carried out only by attaching the attachment, so without additional configuration steps, such. B. Programming or manual switching of the encoder.

In one case, assume an absolute value encoder that has both an (original) singleturn configuration and (switchable preconfigured) multiturn configuration. In an original state, this encoder is operated with the singleturn function. The corresponding single-turn sensor technology also provides the basis for the acquisition and counting of complete revolutions (multiturn). These two functions are eg. B. already integrated cost-effective in a sensor ASIC of the encoder. To generate the multi-turn function, e.g. The following has been done: 1) installation of a battery (add-on element) in the rotary encoder or in its supply line to realize the multi-turn function, especially if there is no operating voltage; and 2) automatically reconfiguring the sensor ASIC from the singleturn function to the multiturn function.

In one embodiment, the singleturn rotary encoder can be converted to a multi-turn encoder within seconds simply by clipping or plugging a built-in a separate housing battery (clip-on). When the battery is plugged in, two contacts for the battery voltage are connected to the basic unit (rotary encoder) at the same time. The encoder recognizes the battery voltages and independently configures itself to a multi-turn encoder. The end user therefore needs a rotary encoder with original singleturn function and a battery with clip-on housing in order to realize the multi-turn function later.

Preferably, the attachment is a self-sufficient power supply unit for providing additional energy, in particular a primary or secondary battery, wherein the interface for directing power to the evaluation unit is set up. Preferably, the evaluation unit is then configured to detect the concerns of the additional energy as soon as the power supply unit is coupled to the interface.

In a further advantageous embodiment, the attachment element is realized by a data connection cable with a mechanical contact, wherein the data connection cable is set up for transmitting angle measurement data to an external display / evaluation unit and wherein the mechanical contact is adapted to be introduced into the interface become.

The attachment can also be a mechanical counter.

The rotary encoder may additionally have a data storage unit.

The housing, the interface and the attachment can be sealed against external environmental influences.

• 1 zeigt ein Blockdiagramm eines Drehgebers der Erfindung;
• 2 zeigt ein Schaltbild eines Drehgebers;
• 3A-C zeigen eine Sequenz eines Zusammenbaus eines Drehgebers;
• 4 zeigt eine alternative Zusammenbauweise;
• 5 zeigt eine perspektivische Ansicht eines zusammengebauten Drehgebers;
• 6 zeigt ein Flussdiagramm eines Zusammenbaus;
• 7A-7B zeigen einen Drehgeber mit angebauter Batterie; und
• 8A-8B zeigen einen Drehgeber mit angebauten Umdrehungszählungskomponenten.

Preferably, the encoder is gearless.

• 1 Fig. 12 is a block diagram of a rotary encoder of the invention;
• 2 shows a circuit diagram of a rotary encoder;
• 3A-C show a sequence of assembly of a rotary encoder;
• 4 shows an alternative assembly method;
• 5 shows a perspective view of an assembled encoder;
• 6 shows a flowchart of an assembly;
• 7A - 7B show a rotary encoder with mounted battery; and
• 8A - 8B show a rotary encoder with attached revolution counting components.

The absolute value singleturn rotary encoder 10 has a housing 12 on which an angle sensor 14 and an evaluation unit 16 so that they are not accessible from the outside. Furthermore, the housing comprises 12 an external physical interface 18 , The housing 12 can also be a code carrier 20 and a program memory 22 for storing data 24 lock in. The code carrier 20 But can also be provided outside the housing, z. B. in the form of a dipole magnet, the front side of a (not shown here) encoder shaft 30 is attached. the interface 18 is furnished, an attachment 26 , such as B. a battery or a plug or the like, preferably to receive form-fitting from the outside.

The evaluation unit 16 can be realized by a microprocessor. The evaluation unit 16 may also include one or more ASICs exhibit. These components are configured so that the encoder 10 can be operated both as a single-turn encoder and as a multi-turn encoder. Primary is the evaluation unit 16 configured for single-turn operation.

The encoder 10 can be coupled to an external display / evaluation unit 28, for. B. display data measured by an end user.

2 shows a circuit diagram of a rotary encoder according to the DE 198 49 108 A1 , which can also be used here with a corresponding configuration.

A code carrier 20 (Code disc) is non-rotatable on a sensor shaft 30 attached. The code carrier 20 triggers a 360 ° rotation of the encoder shaft 30 in a known manner by means of absolute coding in a corresponding number of positions (angle), so that an angular position of the shaft 30 immediately after switching on the rotary encoder 10 is available for one revolution measurement. The absolute coding can be optical, magnetic, inductive or capacitive.

In the example of 2 will be angular changes of the shaft 30 by means of the code carrier 20 and eg three sensors 14 - 1 to 14 - 3 detected. The sensors 14 - 1 to 14-3 can operate optically, magnetically, inductively or capacitively and read a code of the code carrier 20 off and set the measured values of the evaluation unit 16 to disposal. The evaluation unit 16 sets those from the sensors 14 - 1 to 14 - 3 supplied codes in angle and a number of revolutions of the shaft 30 around. The evaluation unit 16 also has the task to suppress electromagnetic interference and possibly make a data correction in case of failure and issue a warning or error message, if z. B. one of the sensors 14 - 1 until 14-3 fails.

With a battery, not shown here, the information of the code carrier 20 or the sensors 14 or evaluation unit 16 be buffered in the event of a power failure.

The sensors 14 - 1 to 14 - 3 be in the 2 supplied with an operating voltage U _Bat , the evaluation unit 16 can be a logic module 32 and a counter module 34 have, which may optionally be formed as a unit. Both modules 32 and 34 are supplied with the battery voltage U _Bat . The sensors 14 - 1 up to 14-3 are constantly energized in the present example. The logic module 32 only occurs when the level of the sensors changes 14 - 1 to 14 - 3 awakened for a short time until appropriate data is processed. That the logic module 32 downstream counter module 34 can be synchronous with the logic module 32 be awakened. In this case, the counters need to 36 to 40 of the counter module 34 by nonvolatile memory, e.g. As EEPROMs, are added, the voltage-free retain the last counter value. But it is also possible the counters 36 to 40 of the counter module 34 constantly energize, despite a high-impedance design of the meter 36 to 40 can be a miscalculation by blocking the counter inputs when switching off the logic module 32 be avoided.

The code carrier 20 , which, for example, consists of a correspondingly magnetized disc or a magnetic ring, modulated upon rotation of the shaft 30 the three sensors 14 - 1 to 14 - 3 that are, for example, reed switches. This creates a sinusoidal code course.

At each edge change the signal level of the sensors 14 - 1 to 14 - 3 energizes the sensors 14 downstream Guardian IC 42 , which is also supplied with the battery voltage U _Bat , the downstream logic module 32 , Between the Guardian IC 42 and the logic module 32 is a switch 44 arranged, which is open as long as the watchdog IC no signal from the respective sensor 14 receives. The logic module 32 thus remains off until it is closed by closing the switch 44 by means of the Guardian IC 42 is energized.

The logic module 32 can be a digital filter 46 have, possibly the glitches, for example. By multiple readout of the logic levels, filters. If an interference pulse has been the cause of the activation of the logic module, a feedback is sent to the guardian IC 42 , The logic module 32 is then switched off without further function.

In the case of a useful signal as a cause for the activation of the logic module 32 become the signals of the sensors 14 from the digital filter 46 a sensor level comparator 48 fed. This compares the read-in level states of the signals of the sensors 14 with values stored in a table. The sensor level comparator 48 are the counters 36 to 40 downstream of the counter module. Depending on the result of the comparison of the sensor level comparator 48 can be one of the counters 36 can be incremented or decremented to 40, or it can be no action or it can be an issue of a warning and then a lock of one of the final counters 36 to 40 or issuing an error. For the last case is the sensor level comparator 48 an error output module 50 downstream.

The counters 36 to 40 is a counter comparator 52 Downstream, constantly checking the contents of the three counters 36 to 40 compares and blocks the counter in case of deviation, corresponding warning 54 to the error output module 50 supplies and an update of the counters 36 to 40 downstream output buffer 58 blocked by the faulty counter. The counters 36 to 40 are each an AND gate 56 to the output buffer 58 connected, over the data 60 be issued.

The 3A to 3C show a sequence of three steps in a side view to a rotary encoder 10 with an original singleturn function ( 3a ) in a rotary encoder 10 with a multi-turn function ( 3c ) to convert.

3A shows a rotary encoder 10 in its design as a single-turn encoder. The housing 12 takes the encoder shaft 30 in itself. An inside of the giver 10 is not shown. On the opposite side is the outer physical interface 18 provided that a mechanical and / or electrical contact 62 may be that from the housing 12 protrudes.

3B shows the situation in which the attachment element 26 in the direction of the arrow 64 into the interface 18 is inserted.

The 3C shows the encoder 10 in a state in which the attachment element 26 (captive) to the housing 12 is coupled. By coupling the add-on element 26 to the housing 12 becomes the rotary encoder 10 automatically reconfigured, as will be explained in more detail below, so that the rotary encoder 10 in the coupled state (also) has a multi-turn function.

4 shows an alternative connection form, in which the attachment member 26 with a (mechanical) nose 68 in a recess, not shown 70 in the case 12 is hung in the direction of the arrow 66 into the interface 18 to be pivoted into it.

5 shows a perspective view of the encoder 10 of the 3 and 4 in a coupled state. The attachment 26 is captive and form-fitting in the interface 18 of the housing 12 added.

With reference to 6 A method is described for reconfiguring an original single-turn rotary encoder into a multi-turn rotary encoder.

In a first step S10 becomes a rotary encoder 10 provided in its original singleturn configuration. In a step S12, a separate attachment element 26 to the interface 18 be coupled. In a step S14 it is queried whether the attachment element 26 is coupled. This query is made by the evaluation unit 16 carried out. Represents the evaluation unit 16 firmly that the attachment 26 not to the encoder 10 is paired, this query is executed again. Is found that the attachment 26 is coupled, is automatically changed to the multi-turn function or configuration in a step S16. Then the procedure ends.

7A shows a block diagram of a rotary encoder 10 in which the attachment element 26 essentially a battery 72 includes. 7B shows a function diagram for 7A ,

The coupling of the add-on element 26 of the 7A to the housing 12 of the rotary encoder 10 configures the encoder originally designed as a single-turn encoder 10 to a multi-turn encoder and at the same time provides the energy for the revolution counting in a no-load state. The encoder 10 has one or more sensors 14 for the singleturn measurement and the revolution measurement. The sensor (s) 14 are in the case 12 integrated. The also integrated in the housing code carrier 20 is set up for single-turn measurement and revolution counting. The logic modules 32 and 34 serve a singleturn evaluation and a rotation count and include a corresponding memory, which is not shown here. Via another (optional) interface 74 can data with the external display / evaluation unit 28 (see. 1 ) be replaced.

The attachment 26 of the 7 has its own separate housing into which the battery 72 is integrated. The attachment 26 supplies the energy for the revolution counting in the operating voltage-free state. Optionally, coding data can also be sent to the logic modules 32 and 34 be transmitted. The reconfiguration is done here eg by evaluating an applied supply voltage. Alternatively, via the interface 18 an electrical connection between two poles (jumpers) not shown here are made.

The 8A and 8B show another encoder 10 ( 8A ) as well as a corresponding functional diagram ( 8B ), in which by coupling the attachment element 26 originally designed as a single-turn encoder encoder 10 is reconfigured to a multi-turn encoder, wherein the attachment 26 Contains components that are needed for revolution counting or determination. The attachment 26 supplies a count to the logic of the single-turn encoder.

In the 8A includes the housing 12 a code carrier 20 - 1 for singleturn measurement, a singleturn sensor 14 - 1 and a logic module 32 - 1 for singleturn evaluation. The logic module 32 - 1 however, is set up to incorporate rotation data.

The singleturn code carrier 20 - 1 is non-rotatable with the encoder shaft 30 connected. Furthermore, another code carrier 20 - 2 provided for a revolution count, within the housing 12 , The code carrier 20 - 2 is preferably arranged so that it is in close proximity to the coupled attachment 26 is positioned.

The 8A shows the attachment 26 in a coupled state. The attachment 26 includes another sensor 14 - 2 to the revolution counting, which is also arranged so that it is in close proximity to the code carrier 20 - 2 is positioned. The attachment 26 also has a logic module 32 - 2 to turn count, a battery 72 (optional) and a revolution counter with corresponding memory. The attachment 26 can also have an energy harvester.

At the rotary encoder 10 of the 8th For example, the reconfiguration from the single-turn rotary encoder to the multiturn rotary encoder can be achieved by a non-contact detection of the add-on element via the components 14 - 22 - 2 (eg, inductive, capacitive, optical, etc.) take place. Alternatively, a micro-switch (not shown) may be actuated when the components 12 and 26 coupled to each other.

In general, the coupling by hooking, swiveling, clipping, attaching, screwing, pressing on, locking by means of e.g. a bayonet closure or similar.

• - Drehgeber mit ursprünglicher Singleturn-Funktion, die mit Hilfe optischer, magnetischer, induktiver oder kapazitiver Verfahren realisiert wird, und deren Funktion durch Anbringen eines Anbauelements von der Singleturn- zur Multiturn-Funktion erweitert wird, ohne dass dazu weitere Konfigurationsschritte notwendig sind.
• - Drehgeber, bei denen die Multiturn-Funktion mit Hilfe mechanischer Zählwerke, die mittels geeigneter Sensorik ausgelesen werden können, realisiert ist.
• - Drehgeber, bei denen die Multiturn-Funktion mit Hilfe elektronischer Umdrehungszähler realisiert ist.
• - Drehgeber mit ursprünglicher Singleturn-Funktion, die Komponenten zur Realisierung der Multiturn-Funktion noch gar nicht, teilweise oder vollständig bereits eingebaut haben, wobei diese Multiturn-Funktion erst durch Anbringen des Anbauteils von der Singleturn-Funktion auf die Multiturn-Funktion erweitert wird, ohne dass dazu weitere Konfigurationsschritte notwendig sind. Entsprechend kann das Anbauelement entweder alle zur Erzeugung notwendigen Komponenten oder Teile davon beinhalten oder im einfachsten Fall ein Codierstecker sein.
• - Drehgeber, bei denen das Anbauelement als Stecker ausgebildet ist.
• - Drehgeber, bei denen das Anbauelement Bestandteil eines ansteckbaren Verbindungskabels ist, wobei die Umschaltung bzw. Umkonfiguration von der Singleturn-Funktion auf die Multiturn-Funktion, also z. B. durch Auswahl eines ohnehin notwendigen Verbindungskabels, erfolgt.
• - Drehgeber, deren Funktion dadurch von Singleturn auf Multiturn umkonfiguriert bzw. umgeschaltet wird, dass sie mit einer externen Auswerteeinheit verbunden werden, die die notwendige Komponente zum Umschalten auf die Multiturn-Funktion beinhaltet (z. B. Versorgungsbatterie oder Steuerkontakt). Auch hier wird durch einfaches Anstecken des Anbauelements an den Drehgeber die entsprechende Konfiguration hergestellt, ohne dass es weiterer Konfigurationsschritte oder einer intelligenten Steuerung bedarf.
• - Drehgeber, die hinsichtlich ihrer Auflösung und sonstigen Funktionalität konfigurierbar sind, z. B. über eine Kommunikationsschnittstelle und deren Funktion durch Anbringen des Anbauelements von der Singleturn-Funktion auf die Multiturn-Funktion erweiterbar sind, ohne dass dazu weitere Konfigurationsschritte notwendig sind.
• - Drehgeber, die einen geringen Schutz gegen Umwelteinflüsse benötigen, und bei denen somit die Anbauzone (Schnittstelle) des Anbauelements nicht speziell abgedichtet sein muss.
• - Drehgeber, die hohe Ansprüche hinsichtlich Dichtheit erfüllen müssen und bei denen somit das Anbauelement selbst und/oder die Anbauzone (Schnittstelle) durch zusätzliche Dichtungsmaßnahmen geschützt sind, wie z. B. durch einen Deckel, elastische Dichtungen oder Ähnliches.

The following embodiments are therefore possible:

• - Rotary encoder with original singleturn function, which is realized by means of optical, magnetic, inductive or capacitive methods, and whose function is extended by attaching an add-on element from the single-turn to the multi-turn function, without the need for further configuration steps are required.
• - Encoders in which the multi-turn function with the help of mechanical counters, which can be read by means of suitable sensors, is realized.
• - Rotary encoders in which the multiturn function is implemented by means of electronic revolution counters.
• - Rotary encoders with original singleturn function, the components for realizing the multi-turn function have not even, partially or completely already installed, this multiturn function is only extended by attaching the attachment from the singleturn function to the multi-turn function, without the need for further configuration steps. Accordingly, the add-on element can either contain all components or parts thereof necessary for the production or, in the simplest case, be a coding plug.
• - Encoders in which the attachment is designed as a plug.
• - Rotary encoder, where the add-on element is part of an attachable connection cable, wherein the switching or reconfiguration of the singleturn function on the multi-turn function, ie z. B. by selecting an already necessary connection cable occurs.
• - Rotary encoders whose function is thereby reconfigured or switched from singleturn to multiturn, that they are connected to an external evaluation unit, which contains the necessary component for switching to the multiturn function (eg supply battery or control contact). Again, the appropriate configuration is made by simply plugging the attachment to the encoder, without the need for further configuration steps or intelligent control.
• - Encoders that are configurable in terms of resolution and other functionality, such. B. via a communication interface and their function by attaching the add-on element of the singleturn function on the multi-turn function can be extended without the need for further configuration steps are necessary.
• - Rotary encoders, which require little protection against environmental influences, and thus where the mounting zone (interface) of the add-on element does not need to be specially sealed.
• - Encoders, which must meet high demands in terms of tightness and in which thus the attachment itself and / or the mounting zone (interface) are protected by additional sealing measures, such. B. by a lid, elastic seals or the like.

The choice of a battery as an attachment has proved to be particularly advantageous because batteries represent relatively expensive components, so that the integration of the battery in the encoder from the beginning from a pricing point not worthwhile. The end user can then reconfigure a rotary encoder to the multiturn function by clipping the battery.

Claims (8)

Absolute single-turn rotary encoder (10) with selectable multiturn function with: an electronic angle sensor (14) and an electronic evaluation unit (16); and a closed housing (12), in which the angle sensor (14) and the evaluation unit (16) are integrated and which has an outer physical interface (18) for coupling an external add-on element (26), wherein the interface (18) for positive reception the external attachment is arranged in the housing (12); wherein the evaluation unit (16) is arranged to be operated both in a single-turn configuration and in a multi-turn configuration; wherein the evaluation unit (16) is further set up: to detect whether the attachment (26) is coupled to the interface (18); automatically switch from the singleturn configuration to the multiturn configuration without any further configuration measures as soon as it has been detected that the add-on element (26) is coupled; and to remain in the singleturn configuration when the attachment (26) is not coupled to the interface (18). Rotary encoder after Claim 1 wherein the add-on element (26) is a self-sufficient power supply unit for providing additional energy, and wherein the interface (18) is adapted for conducting power to the evaluation unit (16). Rotary encoder after Claim 2 wherein the evaluation unit (16) is arranged to detect the concern of the additional energy as soon as the power supply unit is coupled to the interface (18). Rotary encoder after Claim 1 wherein the add-on element (26) is a data connection cable with a mechanical contact, the data connection cable being arranged to transmit angle measurement data to an external display unit (28), and wherein the mechanical contact (62, 68) is fitted in the Interface (18) to be introduced. Rotary encoder after Claim 1 wherein the attachment (26) is a mechanical counter. Rotary encoder according to one of the Claims 1 to 5 further comprising a data storage unit (22). Rotary encoder according to one of the Claims 1 to 6 , wherein the housing (12), the interface (18) and the attachment element (26) are sealed against external environmental influences. Rotary encoder according to one of the Claims 1 to 7 , wherein the rotary encoder (10) is gearless.

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