JP4308082B2 - Drive unit - Google Patents

Description

The present invention relates to a drive unit .

2. Description of the Related Art Conventionally, as a motor, a motor including a rotor and a stator, the rotor has a pair of permanent magnets stacked via disk-shaped magnetic bodies, and each of the permanent magnets is attached in the axial direction. A plurality of magnetized magnetic poles are formed to be different magnetic poles alternately in the circumferential direction, the pair of permanent magnets are opposed to each other in the axial direction, and each of the pair of stators includes an inner ring and an outer ring. A magnetic thin plate stator iron core having a magnetic coil and a magnetic coil is known. (For example, see Patent Document 1).
Japanese Patent Publication No. 6-83561

  However, the motor disclosed in Patent Document 1 has a very large starting torque because a magnetic material such as iron is present in the magnetic field formed between the permanent magnet and the magnetic coil. For this reason, when a solar battery is used as a power source, a battery having a large operating current has to be used.

The present invention has been made in view of such problems, and an object of the present invention is to provide a drive unit incorporating a motor having a small starting torque .

According to a first aspect of the present invention, there is provided a drive unit including a rotor in which a magnet support portion for supporting a permanent magnet is made of a non-magnetic material, a gear mechanism for reducing and transmitting rotational power of the rotor, and an air core coil. A housing having a stator and a substrate on which an unstable multivibrator connected to a solar battery serving as a power source and performing energization control of the air-core coil is mounted ,
The housing includes a first plate and a second plate. The first plate is provided with the stator and a U-shaped engagement portion, and the engagement portion includes the second plate. The substrate is detachably provided from the plate side, and the first plate and the second plate are spaced apart from each other by a screw screwed into a boss of the first plate. Is assembled with the
The rotor shaft of the rotor and the gear shaft of the gear mechanism are spanned between the first plate and the second plate, and the output shaft which is the gear shaft of the final stage gear in the gear mechanism is the Projecting through the second plate,
Four permanent magnets are arranged so that different magnetic poles are alternately arranged at equal intervals along the circumferential direction of the rotor shaft,
Two air core coils are arranged at equal intervals along the circumferential direction of the rotor shaft,
The housing and the gear and gear shaft of the gear mechanism excluding the rotor gear and the rotor shaft are made of a non-magnetic material. Nonmagnetic materials include substances that exhibit diamagnetism, such as gold and copper.

  The installation location of the air-core coil may be a position away from the permanent magnet in the axial direction of the rotor shaft, or may be a position away from the permanent magnet in the diameter direction of the rotor shaft. Further, the overall shape of the air-core coil may be circular, elliptical, rectangular, or the like as viewed from the permanent magnet side, or may be arcuate along the circumferential direction of the rotor shaft. Note that when the permanent magnet and the air-core coil are opposed to each other, it is not always necessary that the center of the permanent magnet and the center of the air-core coil face each other.

  When the permanent magnet is attached to the rotor shaft, the permanent magnet can be directly attached to the rotor shaft, or the permanent magnet can be indirectly attached via the magnet support portion. In the latter case, the magnet support is preferably made of a nonmagnetic material. On the other hand, the rotor shaft is not limited to a non-magnetic material, and may be composed of a magnetic material (for example, metal). This is because the rotor shaft exists at the center of the rotor and rotates together with the rotor, so that it has little influence on the rotating magnetic field generated between the permanent magnet and the air-core coil.

Furthermore, when installing the motor, it is preferable that all the peripheral components in the region that affects the rotating magnetic field generated between the permanent magnet and the air-core coil are made of a non-magnetic material if the magnetic material is brought close to the motor. .

For example, when a magnetic material is brought close, all the parts arranged in a region that affects the rotating magnetic field generated between the permanent magnet and the air-core coil and stops the rotation of the rotor are made of a non-magnetic material. Like that. Such a region can be easily determined by experiments or the like.

Here, the “component” is a concept including the housing itself, and when a component other than the motor (motor external component) is assembled to the housing, it is also used as a concept indicating the motor external component. The “part” refers to a part of the part. Therefore, some parts constituting the drive unit may be non-magnetic, and some of those parts may be non-magnetic. However, it is preferable that all of the casing and the external motor parts provided in the casing are non-magnetic. In this case, the casing is preferably configured to cover the range covered by the rotating magnetic field generated between the permanent magnet and the air-core coil. In other words, even if a magnetic body is installed at an arbitrary location outside the housing, the size and shape are such that the rotating magnetic field generated between the permanent magnet and the air-core coil is not substantially diminished. It is preferable to constitute a housing.

  Further, it is preferable to reduce the weight of the rotor in order to make the rotational resistance as small as possible. For this reason, it is preferable to make the rotor shaft as thin as possible to reduce the weight, or to reduce the weight of the magnet support with a magnet support by devising the shape and material of the magnet support.

A drive unit according to a second aspect is the drive unit according to the first aspect, wherein a projection provided on one surface of a gear of the final stage of the gear mechanism and an insertion hole formed in the second plate And a pin that can be attached to and detached from the insertion hole, and the projection is brought into contact with the pin when the final stage gear is rotated when the pin is attached to the insertion hole.

According to the first and second aspects of the present invention, since the magnet support portion, the gear and gear shaft of the gear mechanism, and the housing are made of non-magnetic material, the rotor can be rotated with a very small operating current. it can. Since an astable multivibrator is used as the energization control means, it is still further compared with the case where an IC is used. Further, since a solar battery is used as a power source, a dry cell or the like is not required, so that energy can be saved.

  FIG. 1 shows an operating device. This operating device 1 is used for placing a product such as a mobile phone on a disk-shaped table 2 which is a final operation component, and displaying the product by rotating the table 2. Here, the “final operation component” refers to a component to be finally operated by the motor. The operating device 1 includes a table 2, a driving device 3 (see FIG. 2), and a solar battery 4. Of these, the driving device 3 is incorporated in the housing 5. The casing 5 is made of a synthetic resin (for example, ABS resin (styrene-butadiene-acrylonitrile copolymer resin)) which is a non-magnetic material.

2A to 2C show the inside of the housing 5. Here, FIG. 6A is a cross-sectional view taken along the line AA in FIG. As shown in FIG. 3, the housing 5 has four sides formed by a rectangular lower plate 5 a and an upper plate 5 b and a lower plate 5 a and an upper plate 5 b that are assembled with each other at a predetermined interval. And a side frame 5c that closes the gap. The shafts 7, 8, and 9 are spanned between the lower plate 5a and the upper plate 5b. The shafts 7, 8, and 9 are installed by temporarily placing the shafts 7, 8, and 9 at predetermined positions on the lower plate 5a and placing the upper plate 5b on the boss 5a-1 of the lower plate 5a. The shafts 7, 8, and 9 are positioned with a nonmagnetic tool inserted through the gap between the plate 5 a and the upper plate 5 b, and the lower plate 5 a and the upper plate 5 b are assembled to each other with screws 6. In this case, the screw 6 is preferably made of a non-magnetic material (for example, brass or synthetic resin). And the housing | casing 5 is completed by making the side frame 5c externally fit with respect to the assembly of the lower board 5a and the upper board 5b which were mutually assembled | attached.

The side frame 5c may be assembled to the assembly with a non-magnetic screw, but the mounting structure is preferably as follows.
That is, as shown in FIG. 3, the claw 5b-1 having a triangular cross section is provided partially (preferably at a plurality of locations) around the upper plate 5b, and the claw 5b-1 is engaged with the side frame 5c. A triangular recess 5c-1 is provided. Then, the side frame 5c can be externally fitted to the assembly from the upper plate 5b side. Then, when the side frame 5c is externally fitted to the assembly from the upper plate 5b side, the claw 5b-1 and the recess 5c-1 are engaged so that the side frame 5c does not come out upward. On the other hand, when the lower plate 5a is formed slightly larger than the upper plate 5b, and the side frame 5c is externally fitted to the assembly from the upper plate 5b side, the end of the side frame 5c becomes the lower frame 5a. The side frame 5c is prevented from coming out downward. When replacing or repairing the components in the housing 5, the side frame 5c can be removed from the upper frame 5b after the screws 6 are removed and the lower frame 5a is removed from the upper frame 5b. . With the mounting structure as described above, the assembly can be easily performed. Needless to say, the upper plate 5b may be formed slightly larger than the lower plate 5a and may have a structure opposite to the above structure.

The shaft (rotor shaft) 7 is a rotor shaft and is made of SUS or brass which is a non-magnetic material. In this case, the shaft 7 is preferably made of a nonmagnetic material, but may be made of a magnetic material. This is because the shaft 7 exists at the center of the rotor and rotates together with the rotor, so that the influence on the rotating magnetic field is small. The shaft 7 is preferably as thin as possible for weight reduction. A magnet support member 10 is attached to the shaft 7. The magnet support member 10 is made of a non-magnetic synthetic resin (for example, POM resin (polyacetal). As shown in FIGS. 4A and 4B, the magnet support member 10 is attached to the shaft 7. A shaft cylinder 11 that fits externally and four magnet support portions 12 that are formed integrally with the shaft cylinder 11 and project in a cross shape outside the rotor shaft are shown in FIG. Although the magnet support 12 may project in an annular shape, it is preferable to project the magnet support 12 radially outside the rotor shaft in accordance with the number of magnets in order to reduce the weight. Permanent magnets 13 are respectively attached to the lower surface of the magnet 10. In this case, the permanent magnets 13 are arranged so that different magnetic poles (N poles and S poles) are arranged alternately at equal intervals in the circumferential direction of the shaft 7. In addition, a small diameter gear 14 is integrally provided on the shaft cylinder 11. The small-diameter gear 14 is made of a non-magnetic synthetic resin (for example, POM resin (polyacetal). The small-diameter gear 14 is preferably made of a non-magnetic material, but may be made of a magnetic material. This is because the small-diameter gear 14 exists at the center of the rotor and rotates together with the rotor, so that it has little influence on the rotating magnetic field.
As the permanent magnet 13, various magnets such as barium ferrite magnets, strontium ferrite magnets, samarium magnets, neodymium magnets can be used. It is preferable to do. The axis 7 may be a square axis, but is preferably a round axis. Then, both end portions of the shaft 7 are inserted into the round holes, and the end portions of the shaft 7 are rounded or sharpened and supported in a substantially point contact state by a metal pivot 20 (for example, Cu) to suppress axial movement. At the same time, it is preferable to reduce rotational friction. Nonmagnetic materials (paramagnetic materials) include substances that exhibit diamagnetism (diamagnetic materials) such as gold and copper. A diamagnetic material has exactly the opposite properties to a ferromagnet, but its action is extremely subtle, so it is included in the paramagnetic material for distinction. In this specification, the term “non-magnetic material” is used according to the classification.
FIG. 5 shows a specific example of the support structure of the shaft 7. In this support structure, the metal pivot 20 receives an axial load. That is, the metal pivot 20 functions as a thrust bearing. On the other hand, the support portion 5-1 having a round hole into which the end portion of the shaft 7 is inserted receives a load applied perpendicularly to the shaft 7. That is, the support portion 5-1 functions as a radial bearing. The thickness of the support portion 5-1 is preferably as small as possible. In the embodiment, the operating device 1 is used so that the shaft 7 is in the vertical direction. However, in some cases, the operating device 1 is used sideways. In this case, the contact area with the shaft 7 is reduced to allow rotational friction. This is to reduce as much as possible. It is preferable that the other shafts 8 and 9 have the same structure.
As described above, the rotor is constituted by the shaft 7, the magnet support member 10 attached to the shaft 7, and the permanent magnet 13. The small diameter gear 14 constitutes a part of the power transmission mechanism.

The shaft 8 is made of a non-magnetic synthetic resin (for example, POM resin (polyacetal). The shaft 8 is integrally provided with a large diameter gear 15 and a small diameter gear 16. The large diameter gear 15 and the small diameter gear. The gear 16 is made of a non-magnetic synthetic resin (for example, POM resin (polyacetal)), and the large diameter gear 15 meshes with the small diameter gear 14.
The axis 8 may be a square axis, but is preferably a round axis. Furthermore, it is preferable that the end of the shaft 8 is rounded or sharpened and supported in a substantially point contact state by a metal pivot (for example, Cu) 21 or the like to suppress axial movement and reduce rotational friction.

The shaft 9 is made of brass which is a nonmagnetic material. A large-diameter gear 17 is provided on the shaft 9. The large diameter gear 17 is made of a non-magnetic synthetic resin (for example, POM resin (polyacetal). A projection 17a is attached to the upper end surface of the large diameter gear 17 as shown in FIG. The large-diameter gear 17 is meshed with the small-diameter gear 16. The shaft 9 extends through the upper plate 5b and above the upper plate 5b.
The axis 9 may be a square axis but is preferably a round axis. Further, the end portion of the shaft 9 is rounded or sharpened and supported by a metal pivot (for example, Cu) 22 in a substantially point contact state, and the shaft tube 23 is fitted on the shaft 9 to suppress axial movement. At the same time, it is preferable to reduce rotational friction.

  A circular table 2 made of a nonmagnetic material is detachably attached to a portion of the shaft 9 protruding from the housing 5. The table 2 is made of a synthetic resin (for example, ABS resin (styrene-butadiene-acrylonitrile copolymer resin)) which is a non-magnetic material.

  Further, two air-core coils (stators) 18 are provided in the housing 5. In the embodiment, the two air-core coils 18 are single-turned, and the number of turns is about 800 to 2000, respectively. This is because if it is less than about 800, rotation does not continue at an operating current (for example, the operating current is about 60 μA), and if it exceeds about 2000, it becomes more expensive than necessary. Preferably it is about 1400 to 1600 times. The energization control of the two air-core coils 18 is configured to be performed by the control device 19.

  The upper plate 5b is provided with an insertion hole 5b-2 as shown in FIG. As shown in FIG. 1, a pin 60 is detachably inserted into the insertion hole 5b-2. The pin 60 inserted into the insertion hole 5b-2 exists at a position where the protrusion 17a abuts as the large-diameter gear 17 rotates. Then, after the protrusion 17a hits the pin 60 as the large-diameter gear 17 rotates, the rotation direction of the rotor and thus the large-diameter gear 17 changes. In this embodiment, since the rotation direction is determined by a delicate magnetic balance acting between the two permanent magnets 13 and the two air-core coils 18, the pin rotates with the rotation of the large-diameter gear 17. This is because if the projection 17a hits 60 and the large-diameter gear wheel 17 and thus the rotor shaft are slightly reversed by the reaction force, the magnetic force balance so far will be lost and rotate in the opposite direction.

  Further, as shown in FIG. 7, the lower plate 5a is provided with an surrounding wall 5a-3 and a cross-shaped projection 5a-4 for positioning the air-core coil 18 on the lower plate 5a. The surrounding wall 5a-3 and the cross-shaped protrusion 5a-4 are also made of a nonmagnetic material. For example, the surrounding wall 5a-3 and the cross-shaped protrusion 5a-4 are integrally formed with the lower plate 5a with a nonmagnetic material. Then, the air core coil 18 is installed in the lower plate 5a by pushing the air core coil 18 into the surrounding wall 5a-3 in a state where the hole of the center of the air core coil 18 is aligned with the cross-shaped protrusion 5a-4. The In this case, the surrounding wall 5a-3 does not need to surround the entire circumference of the air-core coil 18, and may be partially enclosed.

  FIG. 8 is a circuit block diagram including the control device 19. The control device 19 in this case is constituted by an oscillation circuit. A specific configuration of the oscillation circuit is shown in FIG. As this oscillation circuit, an astable multivibrator is used. The solar battery 4 is used as a power source and the two air core coils 18 are alternately energized. The control device 19 is configured on a substrate 25 provided in the housing 5. As shown in FIG. 2B, the substrate 25 can be inserted into and removed from the U-shaped engaging portion 5a-5 of the lower plate 5a from above. In the figure, reference numeral 26 denotes a charging circuit.

  According to the operating device 1 configured as described above, a product such as a mobile phone is placed on the disk-like table 2 which is the final operating component, and the solar battery 4 is installed, for example, under a fluorescent lamp. Thus, the table 2 is rotated, and the product placed on the table 2 can be rotated.

  As mentioned above, although embodiment of this invention was described, it cannot be overemphasized that this invention is not limited to this embodiment, and a various deformation | transformation is possible in the range which does not deviate from the summary.

  For example, in the above embodiment, the air-core coil 18 is installed at a position away from the permanent magnet 13 in the axial direction of the shaft (rotor shaft) 7, but as shown in FIG. On the other hand, it may be a position separated in the diameter direction of the shaft (rotor shaft) 7.

  Further, in the above embodiment, the air-core coil 18 is installed on the one surface side of the permanent magnet 13 in order to set the location away from the permanent magnet 13 in the axial direction of the shaft (rotor shaft) 7. 12, air core coils 18 may be provided at positions where the permanent magnet 13 is sandwiched. In this case, the set of the air-core coils 18 that sandwich the permanent magnet 13 may be one set.

  In the above-described embodiment, the case where the rotor shaft is used vertically (used extending in the vertical direction) has been described. However, even when the rotor shaft is used horizontally, the rotor shaft is also applied. Of course you can.

It is a perspective view of the operating device concerning the present invention. It is a figure which shows the internal structure of the housing | casing of the operating device which concerns on this invention, The figure (A) is sectional drawing along the AA line of the figure (B) of the figure (B) in the state which removed the side frame, B) is a plan view with the upper plate removed, and FIG. 7C is a cross-sectional view showing the rotor shaft mounting structure. It is a perspective view which shows the structure of the housing | casing of the operating device which concerns on this invention. It is a figure which shows the structure of the rotor of the operating device which concerns on this invention, the figure (A) is sectional drawing which shows the principal part of a rotor, and the figure (B) is a bottom view of a rotor. It is a figure which shows the specific example of the support structure of the rotor axis | shaft of the operating device which concerns on this invention. It is a perspective view which shows the structure of one large diameter gear of the operating device which concerns on this invention. It is a top view which shows the structure of the lower board of the action | operation apparatus which concerns on this invention. It is a circuit block diagram of the operating device concerning the present invention. It is a circuit diagram of the oscillation circuit of the operating device according to the present invention. It is a figure which shows the installation place of the air-core coil in the modification of the operating device which concerns on this invention. It is a figure which shows the installation place of the air-core coil in the modification of the operating device which concerns on this invention.

DESCRIPTION OF SYMBOLS 1 Operating device 4 Solar battery 5 Case (housing)
7 axis (rotor axis)
13 Magnet 18 Air-core coil (stator)
19 Energization control device

Claims (2)

A rotor magnet support portion for supporting the permanent magnet is composed of non-magnetic material, and the gear mechanism for transmitting to decelerate the rotational power of the rotor, a stator having an air core coil, a solar battery as a power source And a substrate on which an astable multivibrator is connected to perform energization control of the air-core coil connected to the housing ,
The housing includes a first plate and a second plate. The first plate is provided with the stator and a U-shaped engagement portion, and the engagement portion includes the second plate. The substrate is detachably provided from the plate side, and the first plate and the second plate are spaced apart from each other by a screw screwed into a boss of the first plate. Is assembled with the
The rotor shaft of the rotor and the gear shaft of the gear mechanism are spanned between the first plate and the second plate, and the output shaft which is the gear shaft of the final stage gear in the gear mechanism is the Projecting through the second plate,
Four permanent magnets are arranged so that different magnetic poles are alternately arranged at equal intervals along the circumferential direction of the rotor shaft,
Two air core coils are arranged at equal intervals along the circumferential direction of the rotor shaft,
The drive unit, wherein the casing and the gear and the gear shaft of the gear mechanism excluding the rotor gear and the rotor shaft are made of a non-magnetic material. A projection provided on one surface of the gear of the final stage of the gear mechanism; an insertion hole formed in the second plate; and a pin detachable from the insertion hole, the pin including the insertion hole 2. The drive unit according to claim 1, wherein the projection is abutted by rotation of the gear of the last stage when mounted on the drive unit.

Images