JP6284613B1 - Contactless potentiometer - Google Patents

Abstract

A contactless potentiometer that can be reduced in size and can adjust the total number of outputs as appropriate. A cylindrical sensor unit 30 including at least one set of magnets 10 and a Hall IC 12 is provided, and the magnets 10 and Hall ICs 12 are arranged at positions orthogonal to the rotation axis of the shaft 6 on the peripheral side surface of the sensor unit 30. The contactless potentiometer 1 is arranged. [Selection] Figure 2

Description

  The present invention relates to a contactless potentiometer using a magnet and a magnetic detection element.

  Conventionally, in a contactless potentiometer using a magnet and a magnetic detection element (Hall IC), the magnet and the Hall IC are generally arranged on an extension of the shaft axis of the contactless potentiometer (see Patent Document 1). .

Japanese Patent No. 5329683

  However, in the conventional non-contact type potentiometer, since the magnet and the Hall IC are arranged on the extension line of the shaft axis of the potentiometer, there is a limitation that only one magnet and the Hall IC can be arranged. There is also a problem that the size of the non-contact type potentiometer becomes larger in the direction of the extension of the shaft axis.

  Furthermore, there is also a problem that the total number of outputs of the contactless potentiometer is determined by the number of outputs of the magnet and the Hall IC arranged on the extension line of the shaft axis.

  The present invention has been made in consideration of such a situation, and provides a non-contact type potentiometer that can be downsized in the axial direction of the shaft and can appropriately change the total number of outputs in accordance with specifications. For the purpose.

  In order to achieve the above object, a contactless potentiometer according to the present invention includes a rotatable shaft, a magnet that is rotated by the rotational force of the shaft, and a Hall IC that faces the magnet and detects a change in magnetic flux of the rotating magnet. And comprising. Further, a cylindrical sensor unit including at least one set of magnets and Hall ICs is provided, and the magnets and Hall ICs are arranged at positions orthogonal to the rotation axis of the shaft on the peripheral side surface of the sensor unit.

  In the contactless potentiometer of the present invention, the potentiometer can be reduced in size in the shaft axis direction, and the number of outputs of the entire potentiometer can be changed according to the specification.

It is a side view which shows the external appearance of the non-contact-type potentiometer by embodiment of this invention. It is the sectional view on the AA line of FIG. 1 is an exploded view of a contactless potentiometer according to an embodiment of the present invention. FIG. It is an exploded view of the sensor unit of the contactless potentiometer according to the embodiment of the present invention. It is a principal part perspective view of the sensor unit comprised by the two-stage type by embodiment of this invention. It is an output characteristic figure of the non-contact type potentiometer by the embodiment of the present invention. It is a longitudinal cross-sectional view of the contactless potentiometer by other embodiment of this invention.

  Hereinafter, an embodiment of a contactless potentiometer of the present invention (hereinafter referred to as “this example”) will be described with reference to the drawings. In the present specification and drawings, the same reference numerals are used for members having substantially the same elements or functions, and redundant inventions are omitted.

  1 is a side view showing the appearance of a contactless potentiometer according to the present embodiment, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1, FIG. 3 is an exploded view of the contactless potentiometer, FIG. 4 is an exploded view of the sensor unit, FIG. 5 is a perspective view of a main part when the sensor unit is configured in a two-stage type, and FIG.

  As shown in FIG. 1, the contactless potentiometer 1 of this example is configured by rotatably supporting a shaft 6 with respect to a housing 2. The housing 2 includes a housing case 3, a gear panel 4 that is fitted to the lower end of the housing case 3, and a back cover 5 that is fitted and fixed to the upper end of the housing case 3. Thus, the shaft 6 is rotatably supported.

  As shown in FIGS. 2 to 6, a sensor unit 30 including a magnetic circuit unit that generates a magnetic field and a magnetic detection unit that detects the magnetic field is provided inside the housing 2. In this example, it is a two-stage type in which two sensor units 30 are arranged on the rotation axis of the shaft 6. The sensor unit 30 has a sensor unit including the magnet 10, the Hall IC 12, and the driven gear 33. The sensor unit of this example includes a right sensor unit 35 provided on the right side of the peripheral side portion of the unit case 40 and a left sensor unit 36 provided on the left side of the peripheral side portion so as to face the right sensor unit 35. It is configured. Further, the magnet 10 and the Hall IC 12 of the right sensor unit 35 and the magnet 10 and the Hall IC 12 of the left sensor unit 36 are provided at positions facing each other across the center of the unit case 40.

  The magnetic circuit unit has a magnet 10 and generates a magnetic field. The magnet 10 is connected to the shaft 6 via a gear unit 20 that is a speed reduction mechanism. The magnetic detection unit includes a circuit board 13 having a Hall IC 12 provided at a position facing the magnet 10, detects the magnetic flux generated from the magnet 10 by the Hall IC 12, and responds to the rotation of the shaft 6 through a code (not shown). Output voltage. In this example, a single output type Hall IC is used as an example. However, the Hall IC may be a double output type, and the output form of the Hall IC is not limited.

  The gear unit 20 includes a disk-shaped intermediate gear 22 to which the rotational drive of the shaft 6 is transmitted via a pinion gear 21 attached to the tip of the shaft 6, and an intermediate gear 22 via a pinion gear 22 a of the intermediate gear 22. And a disk-like drive gear 23 to which the rotational drive is transmitted. The drive gear 23 is integrally attached to the lower end of the rod-shaped sub shaft 31. The sub shaft 31 is arranged such that the rotation axis thereof coincides with the rotation axis of the shaft 6.

  A driving bevel gear 32 as a first bevel gear having the same rotation axis as the shaft 6 is connected and fixed to the subshaft 31. The driven bevel gear 32 is connected to a driven bevel gear 33 as a second bevel gear having a rotation axis orthogonal to the rotation axis of the drive bevel gear 32. The driven bevel gear 33 is formed with a cylindrical magnet holder 9 having a storage portion for storing and holding the magnet 10.

  In this example, the drive bevel gear 32 and the driven bevel gear 33 constitute a conversion mechanism that converts the rotational force of the shaft 6 into a direction orthogonal to the magnet and transmits it to the magnet 10. That is, the rotational force of the shaft 6 is transmitted as the rotational force of the magnet 10 through the sub shaft 31, the drive bevel gear 32, and the driven bevel gear 33.

  In addition, by setting the reduction ratio of the gear train of the gear unit 20 to 10 with respect to the shaft 6, it can be set so that the magnet 10 makes one rotation while the shaft 6 makes 10 rotations. As a result, it is possible to detect an electrical rotation angle of 360 ° × 10 rotations = 3600 ° in the shaft 6.

  The intermediate gear 22 and the drive gear 23 of the gear unit 20 are stored in a storage portion 4 a formed on the gear panel 4. The intermediate gear 22 is rotatably supported by a gear pin 24 between a disc-shaped gear plate 25 fixed above the storage portion 4a and the bottom of the storage portion 4a. The gear pin 24 is assembled with the shaft holes of the gear plate 25 and the gear panel 4 as bearings.

  A through hole 4b is formed at the center of the gear panel 4, and the shaft 6 to which the pinion gear 21 is attached is inserted.

  On the upper surface of the gear plate 25, a groove portion 25b for fitting the lower end surface of the sensor unit 30 is formed along the outer peripheral end. A through hole 25a is formed at the center of the gear plate 25, and the sub shaft 31 to which the drive gear 23 is attached is inserted into the through hole 25a. The center position of the through hole 25a is formed to coincide with the rotation axis of the shaft 6.

  The gear plate 25 is fixed to the gear panel 4 by inserting screws 28 through a plurality of screw holes 27 provided in the gear plate 25 and the gear panel 4. The sub shaft 31 inserted through the through hole 25a of the gear plate 25 fixed to the gear panel 4 is locked by the driving gear 23, and the driving bevel gear 32 of the sensor unit 30 is placed at a predetermined position of the locked sub shaft 31. Is fixed. The sub shaft 31 is assembled with the central shaft hole 5a of the back cover 5 as a bearing.

  For example, as shown in FIG. 4, a right sensor portion 35 is provided on the right side of the sensor unit 30, and a magnet holder of a driven gear 33 is provided on a peripheral side portion of a unit case 40 formed in a rectangular tube shape. The holder insertion part 41 for inserting 9 is formed. The holder insertion portion 41 includes an inner hole 41a substantially the same as the diameter of the magnet holder 9, and an outer hole 41b having a larger diameter than the inner hole 41a formed outside the inner hole 41a.

  A flat part 45 for attaching the circuit board 13 is formed around the outer hole 41 b of the unit case 40. In addition, a shaft insertion hole 48 through which the sub shaft 31 is inserted is formed at the center of the unit case 40.

  The disc-shaped magnet 10 is fitted into the magnet holder 9 with the driven gear 33 inserted through the inner hole 41a. The cylindrical pressing ring 44 is attached to the magnet holder 9 with the ring-shaped adjusting washer 43 placed between the magnet holder 9 and the outer hole 41b. Thereby, the driven bevel gear 33 is attached to the unit case 40 in a rotatable state.

  Next, the circuit board 13 on which the Hall IC 12 is mounted is attached to the unit case 40 while maintaining an appropriate distance and positional relationship with respect to the magnet 10. The circuit board 13 is screwed and fixed to the flat portion 45 of the unit case 40 using a board fixing screw 46.

  In the present example, the left sensor unit 36 including the driven gear 33, the magnet 10, and the Hall IC 12 is also provided on the left side of the unit case 40. At this time, the rotation axis of the driven gear 33 of the left sensor unit 36 is disposed so as to coincide with the rotation axis of the driven gear 33 of the right sensor unit 35. In this example, the two sensor portions 35 and 36 are provided on the left and right sides of the unit case 40, but the sensor portions may be provided only on one side.

  As shown in FIG. 5, in this example, in a state where the sub shaft 31 is inserted through the shaft insertion hole 48, the two sensor units 30 a and 30 b are arranged so as to overlap along the extension line of the rotation axis of the shaft 6. This is a two-stage configuration type. The lower sensor unit 30a disposed in the lower stage is fixed to the gear plate 25 by a fixing screw 37 in a state where the lower end surface of the unit case 40 is fitted in the groove portion 25b provided in the gear plate 25. The upper sensor unit 30b disposed in the upper stage is placed on the upper surface of the lower sensor unit 30a in accordance with the axis of the sub shaft 31 protruding from the shaft insertion hole 48 of the lower sensor unit 30a, and is connected using a connecting screw 38. Connected and fixed. The back cover 5 is fixed to the upper surface of the upper sensor unit 30b by screws 39.

  In this example, when the upper sensor unit 30b is connected to the lower sensor unit 30a, the position of the magnet 10 of the upper sensor unit 30b is 90 degrees in the circumferential direction with respect to the position of the magnet 10 of the lower sensor unit 30a. Connect so as to be displaced. That is, when the connected sensor units 30 are viewed from above, the magnets 10 and the Hall ICs 12 are arranged at intervals of 90 degrees along the circumferential direction of the unit case 40. Thereby, the magnetic flux interference which arises between the magnet 10 of the lower sensor unit 30a and the magnet 10 of the upper sensor unit 30b can be avoided, and an accurate measurement can be performed.

  When a new sensor unit is connected to the upper sensor unit 30b to form a three-stage configuration, the position of the magnet of the sensor unit to be added is set in the circumferential direction with respect to the position of the magnet 10 of the upper sensor unit 30b. Connect 90 degrees apart. Thus, according to the contactless potentiometer 1 of this example, magnetic flux interference can be avoided by shifting the position of the magnet of the sensor unit 30 adjacent in the rotation axis direction of the shaft 6 by 90 degrees, and accurate measurement is possible. It can be performed.

  In this example, the sensor units are stacked in a plurality of stages, but a single-stage type may be used.

  In the contactless potentiometer 1 of this example, the rotational force of the shaft 6 is transmitted to the intermediate gear 22 via the pinion gear 21 fitted and fixed to the tip of the shaft 6. Further, the rotational force of the shaft 6 transmitted to the intermediate gear 22 is transmitted to the subshaft 31 via the drive gear 23, and one or more drive bevel gears 32 fixed at appropriate positions on the subshaft 31. Rotate. When the driving bevel gear 32 rotates, the driven bevel gear 33 meshing with the driving bevel gear 32 rotates, and the magnet 10 attached to the magnet holder 9 of the driven bevel gear 33 rotates. Accordingly, the Hall IC 12 of the magnetic circuit unit senses a change in magnetic flux accompanying the rotation of the magnet 10 and outputs an electrical signal such as a voltage corresponding to the rotation angle of the shaft 6.

  FIG. 6 is an output characteristic diagram of the contactless potentiometer of this example, in which the horizontal axis represents the rotation angle of the shaft 6 and the vertical axis represents the output voltage.

  Here, the relationship between the rotation angle of the shaft 6 and the rotation angle of the magnet 10, that is, the relationship between the rotation angle of the shaft 6 and the output change of the Hall IC 12 is that of the gear reduction mechanism including the pinion gear 21, the intermediate gear 22 and the drive gear 23. It depends on the gear ratio and the gear ratio of the bevel gear composed of the driving bevel gear 32 and the driven bevel gear 33.

  In this example, the gear ratio of the gear reduction mechanism is set to 10 times or more with respect to the rotation of the shaft 6. The number of teeth of the driving bevel gear 32 and the number of teeth of the driven bevel gear 33 are the same, and the gear ratio between the driving bevel gear 32 and the driven bevel gear 33 is set to 1. The gear ratio of the gear reduction mechanism and the gear ratio of the bevel gear can be appropriately set according to the specifications of the potentiometer.

  In this example, 10% to 90% of the output voltage is assigned to the rotation angle of the magnet 10 with respect to the electrical rotation angle 3600 ° corresponding to 10 rotations of the shaft 6. In this example, the rotation amount of the shaft 6 accompanied by an electrical change is 10 rotations (electric rotation angle 3600). However, the rotation amount of the shaft 6 and the output level of the output voltage are appropriately set according to the potentiometer specifications. can do.

  In this example, a single output type Hall IC is used for the sensor unit of the sensor unit 30, but if a double output type Hall IC is used, each output of the left and right sensor units is double output. It is also possible.

  In this example, an analog voltage output is used, but a digital output such as PMW may be used. Further, the output is not limited to a linear analog voltage output, and may be a function output such as a triangular wave output, a switch output (square wave output), or a SIN / COS output.

FIG. 7 is a longitudinal sectional view of a contactless potentiometer according to another embodiment of the present invention.
As shown in FIG. 7, the contactless potentiometer 50 of the present example integrally forms the shaft 6 and the sub shaft 31 and eliminates the gear reduction mechanism including the intermediate gear 22 and the drive gear 23 housed in the gear panel 4. A driving bevel gear 32 is directly attached to the sub shaft 31. Thereby, the 1 rotation type non-contact-type potentiometer provided with the some sensor units 30a and 30b can be comprised.

  As described above, according to the non-contact type potentiometer of the present invention, since the sensor unit including the magnet 10 and the Hall IC 12 is not arranged on the extension line of the rotation axis of the shaft 6, the size of the potentiometer in the shaft axis direction can be reduced. Can be small. In addition, a plurality of sensor units can be provided on the peripheral side surface of the sensor unit 30.

  Moreover, the number of sensor parts can be increased by unitizing and connecting a plurality. Thereby, according to the specification of a potentiometer, the output number of the whole potentiometer can be adjusted suitably.

  The contactless potentiometer of the present invention is not limited to the above-described embodiments, and various modifications and changes can be made without departing from the configuration of the present invention in other materials and configurations.

DESCRIPTION OF SYMBOLS 1, 50 ... Non-contact type potentiometer, 2 ... Housing, 3 ... Housing case, 4 ... Gear panel, 5 ... Back cover, 6 ... Shaft, 7 ... Bearing part , 9 ... Magnet holder, 10 ... Magnet, 12 ... Hall IC, 13 ... Circuit board, 20 ... Gear unit, 21 ... Pinion gear (shaft), 22 ... Intermediate gear 22a ... pinion gear (intermediate gear), 23 ... drive gear, 24 ... gear pin, 25 ... gear plate, 25a ... through hole, 25b ... groove, 27 ... screw hole 28 ... Screw, 30 ... Sensor unit, 31 ... Sub shaft, 32 ... Drive bevel gear, 33 ... Follower bevel gear, 35 ... Right sensor part, 36 ... Left Sensor part, 40 ... unit case, 41 ... holder insertion part, 1a ... hole, 41b ... outer hole, 43 ... adjustment washer 44 ... retainer ring, 45 ... flat portion, 46 ... substrate fixing screw, 48 ... shaft insertion hole

Claims (3)

A rotatable shaft,
A magnet that rotates by the rotational force of the shaft;
A non-contact type potentiometer provided with a Hall IC that faces the magnet and detects a change in magnetic flux of the rotating magnet,
A cylindrical sensor unit provided with one set of the magnet and Hall IC and another set of magnet and Hall IC provided at a position facing the one set of magnet and Hall IC ;
The one set and the other set of magnets and Hall ICs are arranged at positions orthogonal to the rotation axis of the shaft on the peripheral side surface of the sensor unit,
A first bevel gear having a rotation axis common to the rotation axis of the shaft, and the magnet having a rotation axis connected to the first bevel gear and orthogonal to the rotation axis of the first bevel gear are held. And a second bevel gear, and a contactless potentiometer that rotates the magnet by transmitting the rotational force of the shaft via the first bevel gear and the second bevel gear . The contactless potentiometer according to claim 1, wherein a plurality of the sensor units are provided, and the plurality of sensor units are arranged so as to overlap each other on a rotation axis of the shaft. The non-contact type according to claim 2, wherein the plurality of sensor units arranged in an overlapping manner are arranged such that positions of the magnets arranged in adjacent sensor units are shifted by 90 degrees in a circumferential direction of the sensor unit. Potentiometer.

Images