JP2003299331A - Fixed shaft type motor having gear portion and gear head - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a geared motor and a gear head which reduce a space occupied by a motor and a gear head when incorporated in a device, obtain a desired driving torque, and suppress the influence of backlash. SOLUTION: A stator portion has a shaft,
In a shaft-fixed motor having a rotor portion in which a shaft is inserted into a bearing and the bearing is rotatably supported about the shaft, a gear portion is provided integrally or fixedly on an outer surface of the rotor portion. At the same time, by fixing both ends of the shaft of the fixed shaft type motor, the fixed shaft type motor is incorporated in the inside of the gear head to form a gear head.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft-fixed motor having a gear portion integrally provided therein, and a gear head incorporating the motor.

[0002]

2. Description of the Related Art Currently, geared motors are used in various devices such as space-saving compact industrial robots and syringe pumps in the medical field.

The geared motor is generally composed of a motor body and a gear head in which multiple gears are combined. Typically, as shown in FIG. 21, a gear 26 is attached to a shaft 9 of a motor 22. The output torque of the motor 22 is transmitted by the rotation of the shaft 9 to increase by engaging the gear 26 with the multi-stage reduction gears inside the gear head 16, and the output torque is taken out from the output shaft 17 of the gear head 16. is there.

[0004]

However, when the gear head is composed of a multi-stage gear in order to increase the output torque, the volume of the gear head becomes large, and when the gear head is incorporated into each device, the gear head occupies the inside of the device. The space also becomes larger. Further, as the number of gears increases, the amount of loss torque lost before the output torque from the motor is transmitted to the output shaft of the gear head also increases. For this reason, the gear head consists of a small number of stages,
It is desired to reduce the size as much as possible.

However, if the gear head is downsized, that is, the number of gears is reduced, the amplification of the output torque tends to be suppressed along with the downsizing. Therefore, in order to make the drive torque extracted from the output shaft of the gear head a desired magnitude, it is necessary to design the motor as large as possible within the allowable occupied volume inside the device.

However, the increase in size of the motor body causes an increase in weight, and the increase in weight makes it difficult to secure the mounting strength to the gear head.

The fixing of the conventional geared motor is shown in FIG.
As shown in, the plate 14b is fixed to the base plate 23, and the motor 22 is fixed to the plate 14a that constitutes the gear head 16. This is because there are two standards for mounting and fixing, and this causes two variations in the meshing of gears 26 to occur in each geared motor during production of geared motors, as well as backlash. The variation was also large.

Therefore, when the rotor portion of the motor 22 is started and stopped, or due to the eccentricity of the rotor portion which is unavoidably produced during manufacturing, the vibration is transmitted to the gear 26, and the gear 26 and the gear head 16 are then transmitted. A geared motor having a small backlash with the internal gear results in a further increase in the amount of the loss torque and a difficulty in quickly transmitting the rotation of the motor 22 to the output shaft 17. Also causes problems. Further, if the backlash varies, the loss torque amount also varies.

The present invention has been made in view of the above problems, and an object of the present invention is to form a geared motor by directly providing a gear portion on the outer peripheral surface of the motor and to construct the geared motor inside the gear head. Is to reduce the space occupied by the motor and the gear head inside each device. This allows
It is possible to provide a geared motor and a gear head that can obtain a desired driving torque while reducing the space occupied by the motor and the gear head inside each device.

Further, when the geared motor is installed inside the gear head, the both ends of the shaft of the motor are supported and installed so that the gear is supported on the basis of the shaft to suppress the variation in the backlash and the influence caused by the backlash. It is a thing.

[0011]

According to a first aspect of the present invention, a stator portion is provided with a cylindrical shaft, the shaft is inserted in a bearing, and the shaft is rotated about the shaft by the bearing. A shaft fixed motor having a supported rotor portion, wherein a gear portion is provided on an outer surface of the rotor portion.

Further, the invention according to claim 2 is the shaft fixed type motor according to claim 1, wherein the stator portion is composed of at least the shaft and an armature, and the armature comprises a plurality of armatures. A core having salient poles and into which the shaft is inserted; and a coil wound around the core, while the rotor part includes a yoke part formed in a cylindrical shape in the axial direction of the shaft. A magnet provided on an inner cylindrical side surface of the yoke portion and bearings provided in openings at both ends of the yoke portion, and the gear portion is provided on the outer surface of the yoke portion with the yoke portion. The armature is housed in the yoke portion by being integrally formed, and the shaft is inserted into the bearing, and the salient pole and the magnet are arranged to face each other. And the magnetic poles of the magnet are magnetically attracted to the salient poles, whereby the rotor portion and the gear portion rotate relative to the stator portion. Is provided.

Particularly, in the motor structure according to claim 2, the number of salient poles of the core is four, and the number of poles of the magnet is two.
It is more desirable to drive the motor in two phases in order to drive the gear portion with high torque and high positioning control.

According to a third aspect of the present invention, in the shaft fixed motor according to the first aspect, the stator portion is composed of at least the shaft and an armature, and the armature has a plurality of elements. A core having salient poles and into which the shaft is inserted; and a coil wound around the core, while the rotor part includes a yoke part formed in a cylindrical shape in the axial direction of the shaft. A magnet provided on an inner cylindrical side surface of the yoke portion and bearings provided at openings at both ends of the yoke portion, and the gear portion is fitted and fixed on an outer surface of the yoke portion. By the shaft being inserted into the bearing, the armature is housed in the yoke portion, the salient pole and the magnet are arranged to face each other, and the coil is powered. A shaft fixed motor, characterized in that the rotor part and the gear part rotate relative to the stator part by magnetically attracting the magnetic poles of the magnet to the salient poles. is there.

According to a fourth aspect of the present invention, in the shaft fixed motor according to the first aspect, the stator portion is composed of at least the shaft and an armature, and the armature has a plurality of elements. The reluctance rotor part has a core having salient poles and in which the shaft is inserted, and a coil wound around the core, while the rotor part is formed in a cylindrical shape in the axial direction of the shaft. And bearings provided in openings at both ends of the reluctance rotor portion, the gear portion is fitted and fixed on an outer surface of the reluctance rotor portion, and the shaft is inserted into the bearing. Thus, the armature is housed in the reluctance rotor portion, and the salient poles and the inner cylindrical side surface of the reluctance rotor portion are arranged to face each other,
Further, by providing a cutout on the outer side surface, sections having different reluctance generated between the outer side surface and the salient pole are circumferentially divided, and the coil is fed to supply power to the salient pole. The magnetic flux generated in the magnetic field attracts a small reluctance section of the section to the salient poles, whereby the rotor section and the gear section rotate relative to the stator section. A shaft fixed motor is provided.

Further, the invention according to claim 5 is the shaft fixed type motor according to any one of claims 2 to 4, in which a slit is provided on a part of the outer peripheral surface of the shaft,
A ring is fitted around the slotted portion, the ring is inserted into the bearing, and a conductive wire for feeding power to the coil is housed in the slitted portion, and the conductive wire is external to the rotor portion. The present invention provides a fixed shaft type motor, which is characterized in that the motor is fixed to the shaft.

According to a sixth aspect of the present invention, in the shaft-fixed motor according to the second to fourth aspects, a ring is fitted to the shaft, a groove is provided on the inner peripheral surface of the ring, and the ring is attached. Inserted in the bearing, further,
Pass the conductive wire for power supply to the coil to the groove,
The present invention provides a shaft-fixed motor that is drawn out of the rotor unit.

Further, according to a seventh aspect of the present invention, in a gear head including a gear provided in multiple stages and a plate rotatably supporting the gear, both ends of the shaft are fixed to the plate. According to another aspect of the present invention, there is provided a gear head comprising the shaft fixed motor according to any one of claims 1 to 6 incorporated therein.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION <First Embodiment> A first embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a perspective view showing a rotor portion 2 of a shaft fixed motor (hereinafter, abbreviated as geared motor) having a gear portion according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing the stator portion 7 of the geared motor.

In FIG. 1, the rotor portion 2 is a yoke portion 3
And bearings 4a and 4b, and a magnet 6. The yoke portion 3 is formed by forming a magnetic material into a cylindrical shape in the axial direction of a shaft (not shown), and has openings at both ends thereof. Furthermore, on its inner cylindrical side surface,
A magnet 6 formed in a cylindrical shape concentric with the yoke portion 3 is inserted and fixed, and each opening is
Bearings 4a and 4b, both of which have the same outer diameter, are press-fitted and provided. A gear portion 5 is integrally formed on the outer surface of the yoke portion 3 by cutting and gear cutting a magnetic material.

Next, the stator portion 7 will be described with reference to FIG. The stator part 7 is composed of an armature 8, a cylindrical shaft 9 and a ring 10. The armature 8 is further composed of one core and four coils. The core 11 has four salient poles 11a, 11b every 90 degrees.
11c, 11d with coils 12a, 12 on the throttle of each salient pole
Each of b, 12c and 12d is wound. The outer shape of each salient pole is formed in an arc shape, and the shaft 9 is inserted and fixed in a hole provided at the center of the core 11. Further, a slitting portion 9a is provided on a part of the outer peripheral surface near the one end of the shaft 9 and on the end surface, and the conductive wire 13 for power feeding drawn out from each coil is accommodated in the slitting portion 9a. To be done.
The ring 10 covers the slot 9a so that it covers a part of the slot 9a.
Fitted around 9a.

Next, referring to FIG. 3, the rotor portion 2 will be described.
Also, the assembly of the stator portion 7 will be described. First, the yoke portion 3 in which the magnet 6 is inserted and fixed on the inner cylindrical side surface.
The bearing 4a is press-fitted into the gear-side opening of the. next,
The stator portion 7 is inserted into the hole of the magnet 6 while inserting one end of the shaft 9 into the hole of the bearing 4a. The armature 11 is now housed in the yoke portion 3.

Further, the ring fitted to the slot 9a
Insert 10 into the hole of bearing 4b. Since the hole diameter of the bearing 4b is formed to be approximately the same as the outer diameter of the ring 10, the outer diameter surface of the ring 10 and the inner hole surface of the bearing 4b slide with each other. The hole diameter of the bearing 4b is set larger than the hole diameter of the bearing 4a. And bearing
4b is press-fitted into the other opening of the yoke portion 3. The appearance of the geared motor 1 assembled by the above steps is shown in FIG.

Next, a gear head incorporating the geared motor 1 will be described with reference to FIG.
As shown in FIG. 5, the geared motor 1 has a gear head in which both ends of the shaft are press-fitted and fixed by two plates 14a and 14b.
16 Installed inside. The gear head 16 is composed of a gear 15 provided in multiple stages (three stages in FIG. 5) (only a pitch circle is indicated by a chain line for the sake of omission), and two plates 14a and 14b rotatably supporting the gear 15. To be done. Then, the output torque from the geared motor 1 is amplified by the gear 15 and is transmitted from the output shaft 17 to a device incorporating the gear head 16.

By fixing the geared motor 1 at both ends of the shaft as shown in FIG. 5, both ends of the gear portion 5 provided on the geared motor 1 are supported. As a result, as compared with the conventional geared motor shown in FIG. 21, the gear portion 5 is fixed with the shaft 9 as a reference and at both ends, so that vibration generated when the motor 1 main body and the gear portion 5 are rotationally driven is suppressed. Or reduced. As a result, variations in backlash generated between the gear heads 16 and the teeth of the gears 15 can be reduced, so that variation in loss torque can be reduced and accurate positioning control can be realized. Therefore, it is possible to obtain a desired drive torque while suppressing an increase in the size of the motor.

Further, since the geared motor 1 of this embodiment has a structure in which the bearings 4a and 4b are press-fitted and supported at both ends of the yoke portion 3, it is possible to incorporate two bearings into the geared motor 1 with high axial accuracy. is there. If the shaft precision of the two bearings is high, the shafts inserted and supported by the bearings can also support the rotary shaft with high shaft precision. These technical elements also contribute to the suppression and reduction of the shake and the variation in backlash. Furthermore,
Since the gear portion 5 is provided integrally with the yoke portion 3, the output torque and rotation of the motor 1 are transmitted to the gear portion 5 without loss.

Furthermore, when the shaft end side provided with the slit portion 9a is press-fitted into the hole of the plate 14b, the shaft 9 is bent in the space of the slit portion 9a, so that the shaft 9 is slightly shrunk in the radial direction.
Pressed in. Therefore, the shaft 9 can be press-fitted without damaging the hole of the plate 14b at the time of press-fitting, and the hole is not damaged, so that the shaft 9 can be more firmly fixed.

As shown in FIG. 2, it is desirable that the slot 9a be formed so that the outer peripheral surface and the end surface of the shaft 9 are continuous. If formed in this way, one processing step is sufficient, and the number of steps and the process time can be shortened.

Next, the driving of the main body of the geared motor 1 will be described with reference to FIG. FIG. 6 is a cross-sectional view of the geared motor 1 of FIG. 4 taken along the AA axis. As shown in FIG. 6, the salient poles 11a to 11d are arranged so as to face the inner side surfaces of the magnet.

Now, the coils 12a and 12c are energized to make the salient pole 11a
Is magnetized to the N pole and 11c to the S pole, and the state in which the N pole of the magnet 6 is magnetically attracted to the salient pole 11c and the S pole to 11a is shown in FIG. With this state as the initial state, the description will be continued thereafter.

From the state shown in FIG. 3A, the coils 12b and 12d are also energized to excite the salient pole 11b as the N pole and 11d as the S pole. In this state, the salient poles 11a and 11b are the N pole, and the salient pole 11c.
Since 11d and 11d are respectively excited by the S pole, each magnetic pole of the magnet 6 is magnetically attracted from two adjacent salient poles. Therefore, of the magnetic poles of the magnet 6, the portion having the strongest magnetic flux, that is, the central portion of each magnetic pole is magnetically attracted from the two salient poles and magnetically balanced between the two salient poles, so that a stable state is achieved. take. Figure above
Shown in (b). In this state, the magnet 6, the yoke portion 3, and the gear portion 5 (hereinafter, collectively referred to as a rotor portion as needed) are relative to the stator portion from the state of FIG. It can be said that it has rotated 45 degrees and stopped.

Next, the coils 12a and 12c from the state of FIG.
When the power is turned off, the magnetic poles of the magnet 6 are
Magnetically attracted only to 1d, the strongest magnetic flux of each magnetic pole of the magnet 6, that is, the center of each magnetic pole, is the salient pole 11b.
And come in front of 11d. The above state is shown in FIG. In this state, the rotor part is
It can be explained as a state in which it has rotated 5 degrees and stopped.

Next, the coils 12a and 12c from the state of FIG.
The energization is started, and this time, the salient pole 11c is excited to the N pole and 11a to the S pole. Then, as described above, the central portion of each magnetic pole of the magnet 6 tries to attain magnetic balance between the two sets of the adjacent salient poles 11b and 11c, and 11d and 11a, so that the rotor portion is
From the state of (c), it rotates further 45 degrees in the direction of arrow R and stops. This state is shown in FIG.

Next, from the state shown in FIG. 2D, the coils 12b and 12b
When the power supply to d is cut off, the magnetic poles of the magnet 6 become the salient poles 11a.
The central portion of each magnetic pole of the magnet 6 comes to the front of the salient poles 11a and 11c by being magnetically attracted only to 11c. Figure above
Shown in (e). From this figure (d), this state can be further explained as a state in which the rotor portion has rotated 45 degrees in the direction of arrow R and stopped.

As described above, the rotor portion can be rotated and stopped by repeating the control in which the adjacent salient poles are energized so that they have the same polarity and the energization is sequentially cut off. Therefore, it is possible to rotate the gear portion 5 to rotate the gear 15 in the gear head 16 and transmit the output torque of the geared motor 1 to the output shaft 17. Further, since the rotor portion can be stopped by 45 degrees, it is possible to stop the gear portion 5 at an arbitrary position with a minimum resolution of 45 degrees. In the present invention,
In a motor with four salient pole cores, the opposing salient poles (11a and 11c, and 11b and 11d) have different polarities, and the two-phase drive method is used by shifting the phase by 90 degrees in terms of electrical angle. It is defined as

The driving method shown in FIG. 6 was a method of rotating the rotor portion with a resolution of 45 degrees, but depending on the usage form and purpose of the geared motor 1, there are cases where such a fine resolution cannot be obtained. . In such a case, the rotor portion may be rotated with a resolution of 90 degrees as shown in FIG.
The driving method will be described below.

FIG. 7A shows an initial state (a state in which no coil is energized), and from this state, the coils 12b and 1
When 2d is energized to excite the salient pole 11b as the N pole and 11d as the S pole, magnetic attraction works between the salient pole 11b and the S pole of the magnet 6, and between the salient pole 11d and the N pole of the magnet 6. The rotor portion rotates / stops in the direction of arrow R, and changes from the state shown in FIG. 9A to the state shown in FIG.

Next, in the state shown in FIG. 3B, the coil 12b
When 12a and 12c are energized and salient pole 11a is magnetized to S pole and 11c is magnetized to N pole respectively, salient pole 11a and N pole of magnet 6 and salient pole 11c are excited. Magnetic attraction acts between the S pole of the magnet 6 and the rotor portion further rotates 90 degrees in the direction of arrow R and then stops.
It becomes the state of.

Thereafter, the N poles are excited in the order of salient poles 11d → 11a → 11b → 11c → ... (In accordance with the N pole excitation, 1
The salient poles facing each other at 80 degrees are 11b → 11c → 11d → 11a → ・ ・
The S pole is excited in the order of), and each rotor is repeatedly energized to rotate and stop the rotor portion in the direction of arrow R.

The driving method shown in FIGS. 6 and 7 is selected more optimally according to the drive target of the geared motor 1 or the control purpose. When it is desired to drive the gear unit 5 while positioning it with a finer resolution, or to drive the gear unit 5 with a large output torque, the configuration shown in FIG. 6 is more appropriate. If it is not possible, the one shown in FIG. 7 may be selected.

Further, when it is desired to obtain a larger output torque, the driving method shown in FIG. 8 is optimal. This drive method will be briefly described. First, with the same figure (a) as the initial state, the coils 12a and 12b are energized so that the salient poles 11a and 11b become N poles, and at the same time, the salient poles 11c and 11d are turned on. The coils 12c and 12d are also energized so as to have the south pole.

Then, the central portions of the respective magnetic poles of the magnet 6 are magnetically attracted from the two salient poles respectively, and magnetically equilibrium is established between the salient poles to attain a stable state, so that the rotor portion is shown in FIG. From the state, rotate in the direction of arrow R, stop and then the same figure
It will be in the state of (b).

Next, the salient poles 11a and 11b are S poles, and 11c and 11d are N poles.
The energization of each of the coils 12a to 12d is switched so as to form the pole.

Then, the central portions of the magnetic poles of the magnet 6 are brought into the state shown in FIG. 6 (c) and are in a stable state. This state can be explained as a state in which the rotor portion has rotated 180 degrees in the direction of arrow R from the state shown in FIG.

As described above, the salient poles 11a and 11b, 11c and 11d
By repeating the excitation operation so that the pair will have different polarities,
The rotor portion is repeatedly rotated in the direction of arrow R and stopped.
Therefore, the resolution is 180 degrees.

As described above, in the present embodiment, the gear portion is integrally formed with the yoke portion, which is one of the rotor portions, to form a geared motor, and the geared motor is incorporated into the gear head. It is possible to reduce the space and weight occupied by the motor and the gear head inside the device, as compared with the geared motor of FIG.
Since the occupied space and the weight are small, it is easy to secure the mounting strength to the device, and the positioning accuracy of the mounting position is easily obtained.

Further, the geared motor of this embodiment has many functions such as integrally forming the gear portion and the yoke portion into one component, and further having the yoke portion also function as a bearing support. Since it is integrated into one part, the structure of the geared motor is simplified and the outer diameter of the motor body can be made smaller.

In order to ensure the ease of pulling out the conductive wire 13 to the outside of the motor with the downsizing of the motor,
The geared motor 1 has a structure in which the shaft 9 is provided with a slit portion 9a, and the conductive wire 13 is housed therein and pulled out to the outside of the motor. Thereby, even if the motor becomes small, the work of pulling out the conductive wire can be easily performed.

Further, in the present embodiment, the ring 10 is fitted around the slotted portion 9a, and the inner hole surface of the ring 10 and the outer peripheral surface of the bearing 4b are slid to form the hole surface of the bearing 4b. The structure is such that the slot 9a does not directly slide. As a result, it is possible to prevent the inner hole surface of the bearing 4b from being worn due to the sliding of the rotor portion 2 with respect to the slotted portion 9a, thereby improving the reliability and extending the life of the geared motor.

The geared motor and gear head of this embodiment can be variously modified in accordance with the technical idea thereof.
For example, by changing the gear unit 5 to a bevel gear or the like, the shaft 9
The direction of the output shaft 17 may be changed.

Further, as shown in FIG. 9, the entire length of the gear portion 5 may be matched with the entire length of the yoke portion 3 in the shaft direction, and then the gear portion 5 may be provided on the entire yoke portion 3. In this way, the total length of the gear portion 5 depends on the purpose of use of the geared motor 1,
Alternatively, various changes can be made according to the usage form. Also,
The gear portion 5 of FIG. 9 is formed into a worm gear, and the shaft 9
A large gear ratio may be obtained between the output shaft 17 and the output shaft 17.

In this embodiment, the four salient pole core magnet rotating type has been described as an example of the motor structure inside the yoke portion 3. However, the motor structure is, for example, a magnet fixed coreless coil outer rotation type. Needless to say, it can be replaced with various outer rotor type configurations such as.

<Second Embodiment> Next, a second embodiment of the geared motor of the present invention will be described with reference to FIG. It should be noted that the description of the second embodiment will be made only with respect to differences from the first embodiment, the same components as those of the first embodiment will be denoted by the same reference numerals, and overlapping description will be omitted or simplified. To do.

As shown in FIG. 10, the geared motor of the second embodiment differs from the geared motor 1 of the first embodiment in that the yoke portion 3'and the gear portion 5'are divided into separate parts. 5'is fitted and fixed on the outer peripheral surface of the yoke portion 3 '.

With the above structure, the yoke portion and the gear portion can be formed separately, so that the forming means is simplified and the gear portion is different from the yoke portion, as compared with the first embodiment. Can be made of materials. Therefore, it is possible to improve the reliability and extend the life of the entire geared motor by forming the gear portion with a material stronger than the magnetic material.

<Third Embodiment> Next, a third embodiment of the geared motor of the present invention will be described with reference to FIG. The description of the third embodiment will be made only on the points different from the first and second embodiments, the same components as those of the first and second embodiments will be denoted by the same reference numerals, and overlapping description will be omitted. , Or abbreviated.

As shown in FIG. 11, the geared motor of the third embodiment differs from the geared motors of the first and second embodiments in that the cylindrical magnet 6 is eliminated and the inner cylindrical side surface of the yoke portion 3 is removed. Magnet by depositing a magnetic thin film layer
6'is provided. As a result, the magnet 6
Since the space for housing is unnecessary, it is possible to reduce the size of the yoke portion 3 in the radial direction by that amount, and it is possible to form a more compact geared motor.

Further, if the size of the core in the radial direction is expanded to the space in which the magnet 6 is housed without changing the size of the yoke portion 3, more conductive wires can be wound, so that each coil is made larger. Can be something. By increasing the number of windings, the torque constant can be increased to obtain a larger output torque while the gear diameter is the same, and the torque can be increased to form a geared motor that can be easily controlled.

<Fourth Embodiment> Next, a fourth embodiment of the geared motor of the present invention will be described with reference to FIGS. It should be noted that the description of the fourth embodiment will be made only on the points different from each of the above-described embodiments, and the same components as those in each of the above-mentioned embodiments will be given the same reference numerals,
Overlapping descriptions are omitted or abbreviated.

The geared motor 18 of the fourth embodiment is different from the geared motors of the above-described embodiments in that the rotor section is different.
It is a motor configuration that does not use magnets in 19. FIG. 12 is a perspective view showing the rotor portion 19 of the geared motor according to the fourth embodiment of the present invention.

In FIG. 12, a rotor portion 19 is a cylindrical reluctance rotor portion 3 "made of a magnetic material and a bearing.
It is composed of 4a and 4b. Reluctance rotor part 3 "
On the outer surface of the cylinder, six cutouts 21a are provided at equal intervals over the entire circumference, and the shape of the cutouts 21a is set to a concave shape as shown in FIG. Notch 21 like this
By providing a, on the entire circumference of the outer surface of the cylinder, a portion 21d that is notched except for both ends 21e, a portion 21b where the outer surface of the cylinder is left over both ends 21e, and the central portion only. Three places 21c where the outer surface of the cylinder is left are provided, and a total of 18 sections are circumferentially divided. Further, the gear portion 5'is fitted and fixed on the outer surface of the reluctance rotor portion 3 ".

As shown in FIG. 13, the assembly of the rotor portion 19 and the stator portion 7 is basically the same as that of FIG.
The difference is that since the magnet 6 is not used, the stator portion 7 is housed inside the reluctance rotor portion 3 ", and the reluctance rotor portion 3" and the gear portion 5'are separated into different parts. This means that the gear portion 5 ′ is fitted and fixed on the outer peripheral surface of the reluctance rotor portion 3 ″.
Geared motor 18 assembled by the above process
Is shown in FIG.

Next, driving of the geared motor 18 will be described with reference to FIGS. 16 and 17. 16 is shown in FIG.
FIG. 17 is a sectional view of the geared motor 18 of FIG. 4 taken along the line A-A, and FIG. 17 is an enlarged view of the elliptical two-dot chain line portion of FIG.
FIG. 17 is an enlarged view of an essential part corresponding to the stator portion 7 when the stator portion 7 is housed in the reluctance rotor portion 3 ″. In addition, in FIG. In addition, the location 21c is shown as a parallel horizontal line, and the location 21d is not shown.

When the coils 12b and 12d are energized to excite the salient pole 11b as the N pole and 11d as the S pole from the state of FIG. 16 (a) (the state in which no coil is energized), the salient pole is generated. 11b
And 11d, and the locations 211b, 2 located near the salient poles 11b and 11d.
Flow of magnetic flux occurs between 12b, 211c and 212c ((b) in the figure)
reference). Two of them 211b and 211c and salient pole 11b
FIG. 17 shows the flow of magnetic flux between and, and the driving description of the geared motor 18 will be further described with reference to this drawing.

As shown in FIG. 17, by exciting the salient pole 11b to the N pole, a magnetic flux flows between the two locations 211b and 211c through both ends 21e. Of these, point 211
Where b is the magnetic flux generated over both ends 21e,
Since the cylindrical outer surface of the reluctance rotor portion 3 "is cut away in the portion 211c except for the central portion, the flow of magnetic flux does not occur at the location of the ellipse two-dot chain line portion in the figure. The location 211d leaves both end portions 21e. Therefore, the flow of magnetic flux does not occur because the outer surface of the cylinder is all cut out.Therefore, the most magnetic flux flows in the place 211b among the three places, which means that the place 211b has a smaller magnetic flux than the places 211c and 211d. This means that the flow is easy, that is, the magnetic resistance (reluctance) is small.
Since the salient poles 11b are attracted to the salient poles 11b more strongly than 1c by the magnetic action, the rotor portion 19 and the gear portion 5'rotate relatively in the direction of arrow R with respect to the stator portion shown by the broken line in FIG. The state shown in (c) of FIG. From the above, it was found that the points 21b, 21c, and 21d shown in FIG. 12 have different reluctance values. Therefore, hereinafter, the point 21b is referred to as the attraction electrode, the point 21c is referred to as the rotational excitation electrode, and the point 21d is collectively referred to as the point 21d. It is called a blank pole.

Next, in the state of FIG. 16 (c), the coil 1
By energizing 2a and 12c to excite the salient pole 11a to the S pole and 11c to the N pole respectively, the attraction poles located near the salient poles 11a and 11c
A magnetic flux flows in 213b and 214b and the rotation excitation poles 213c and 214c. Then, as explained in FIG. 17, an imbalance occurs in the flow of the magnetic flux between the attraction pole and the rotation excitation pole, so that more magnetic flux flows through the attraction poles 213b and 214b, and the salient poles 11c and 1c.
It is magnetically attracted to 1a. Therefore, from the state of FIG. 16 (c), the rotor portion and the gear portion further rotate in the direction of arrow R,
The state of (d) is reached.

Thereafter, the N-pole excitation is performed in the order of salient poles 11d → 11a → 11b → 11c → ... (In accordance with the N-pole excitation, the salient poles facing each other at 180 degrees are 11b → 11c. → 11d → 11a
The S pole is excited in the order of → ...) and the energizing operation is repeated for each coil, whereby the rotor portion and the gear portion are rotationally driven in the arrow R direction.

Geared motor rotationally driven in this way
By incorporating 18 into the gear head 16 as in the geared motor 1 of FIG. 5, the output torque from the geared motor 18 is amplified by the gear 15 and transmitted from the output shaft 17 to the device incorporating the gear head 16. Go.

As described above, the structure of the geared motor 18 is
By using a reluctance type that does not use a magnet, compared to a geared motor that uses a magnet, it is possible to suppress the effect of rotational leakage magnetic flux on the built-in equipment and reduce the number of parts of the geared motor.
The manufacturing cost of the entire geared motor can be reduced.

Further, since the notch 21a is provided and the sections having different reluctance values are divided and formed on the cylindrical side surface of the reluctance rotor portion 3 ", the reluctance motor can be formed without increasing the thickness of the reluctance rotor portion 3". At the same time, it is possible to reduce the size and weight of the geared motor 18.

As shown in FIG. 15, the cutout 21a is formed.
By covering the exposed portion of the cover 27 with the stator portion 7
Since it is possible to prevent the leakage of the magnetic flux generated from each coil (only 12a and 12b are shown in the figure), it is necessary to use the cover that covers the exposed portion of the notch so that the geared motor 18 is incorporated in the device. It can be said that this is more preferable.

The present embodiment can be variously modified without departing from the gist thereof. For example, the shape of the rotary excitation electrode 21c is trapezoidal as shown in FIG. 18 (a), or FIG. 18 (b).
It is also possible to have a trapezoidal shape on one side and a 90 degree cutout on the other side as shown in.

Further, as shown in the sectional view of FIG. 19, the rotary excitation pole 21c is abolished, and the attraction pole 21b is gradually reduced in thickness in the circumferential direction of the reluctance rotor portion 3 ".
You may form the inner shape e of.

Furthermore, the geared motor of the present invention can be variously modified without departing from the spirit of the invention. For example, as shown in FIG. 20, the conductive wire 13 is provided with a groove 20 on the inner peripheral surface of the ring 10. Alternatively, each conductive wire 13 may be passed therethrough.

[0076]

As described above, according to the invention of claim 1, the gear portion is integrally formed on the outer surface of the rotor portion of the motor,
Alternatively, since it is provided by being fitted and fixed, the output torque and rotation of the motor can be transmitted to the gear portion without loss.

Further, according to the second aspect of the present invention, the gear portion and the yoke portion are integrally formed into one component, and the yoke portion also has a function as a bearing support member, which has many functions. Since the components are integrated into one component, the structure of the geared motor is simplified and the outer diameter of the motor body can be made smaller.

Further, according to the invention of claim 3, the yoke part and the gear part are divided into separate parts and can be formed separately. Therefore, compared with the invention of claim 2, the forming means of each part is formed. Can be simplified. Furthermore, by forming the gear portion with a material that is stronger than the magnetic material, it is possible to improve the reliability and extend the life of the entire geared motor.

Further, according to the invention of claim 4, compared with a geared motor using a magnet, it is possible to suppress the influence of the rotational leakage magnetic flux on the built-in equipment, and the number of parts of the geared motor is also reduced. Since it can be reduced, the manufacturing cost of the entire geared motor can be reduced.

Further, since the notch is provided and the cylindrical side surface of the reluctance rotor portion is divided into sections having different reluctance values, the reluctance motor can be formed without increasing the thickness of the reluctance rotor portion.
It is possible to reduce the size and weight of the geared motor.

According to the invention of claim 5 or 6,
Even if the motor is downsized, the work of pulling out the conductive wire can be easily performed.

Further, according to the invention described in claim 7, by fixing the geared motor at both ends of the shaft, the gear portion provided on the motor is supported at both ends. Therefore, the gear portion is fixed with the shaft as a reference and is fixed at both ends of the shaft, so that the vibration generated when the motor body and the gear portion are rotationally driven is suppressed and reduced. As a result, it is possible to reduce the variation in backlash generated between the gear head and the gear of each gear head, so that the variation in loss torque can be reduced. Therefore, a desired drive torque can be obtained while suppressing an increase in the size of the motor.

In the geared motor according to the second, third or fourth aspect of the invention, since the bearings are press-fitted and supported at both ends of the yoke portion, the two bearings can be incorporated in the geared motor with high axial accuracy. is there. Therefore,
Since the shaft inserted and supported by the bearing can also rotate with high axial accuracy, it contributes to the suppression and reduction of the shake and the reduction of backlash.

[Brief description of drawings]

FIG. 1 is a perspective view showing a rotor portion of a shaft fixed type geared motor according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a stator portion of the geared motor.

FIG. 3 is a perspective view illustrating assembly of a rotor unit and a stator unit.

FIG. 4 is a perspective view showing a geared motor configured by assembling a rotor portion and a stator portion.

FIG. 5 is a perspective view showing a gear head configured by incorporating the geared motor of the present invention.

6 is a sectional view of the geared motor of FIG. 4 taken along the line AA,
Sectional drawing explaining the driving method.

7 is a cross-sectional view illustrating another driving method of the geared motor of FIG.

FIG. 8 is a cross-sectional view illustrating still another driving method of the geared motor of FIG.

FIG. 9 is a perspective view showing another form of the gear portion.

FIG. 10 is a perspective view showing another form of the gear portion and the yoke portion.

FIG. 11 is a perspective view showing another form of a magnet.

FIG. 12 is a perspective view showing a rotor portion of a shaft fixed type geared motor according to a fourth embodiment of the present invention.

FIG. 13 is a perspective view illustrating assembly of a rotor unit and a stator unit.

FIG. 14 is a perspective view showing a geared motor configured by assembling a rotor portion and a stator portion.

FIG. 15 is a perspective view showing a state where a cover is attached to the geared motor of FIG.

FIG. 16 is a cross-sectional view illustrating the driving method of the geared motor of FIG. 14 taken along the line AA.

FIG. 17 is an enlarged view of a main part of the elliptical two-dot chain line portion of FIG.

FIG. 18 is a perspective view showing another form of the reluctance rotor unit.

FIG. 19 is a cross-sectional view showing still another form of the reluctance rotor unit.

FIG. 20 is a perspective view showing another form of a method of drawing out a conductive wire.

FIG. 21 is a plan view showing a conventional geared motor.

[Explanation of symbols]

1, 18 ... Geared motor 2, 19 ... Rotor part 3, 3 '... Yoke part 3 "; ・ ・ ・ Reluctance rotor part 4a, 4b ・ ・ ・ Bearing 5, 5 '... Gear part 6, 6 '... Magnet 7 ... Stator 8 ... Armature 9 ... Shaft 10 ... Ring 11 ... Core 11a, 11b, 11c, 11d ... salient poles 12a, 12b, 12c, 12d ... Coil 13 ... Conductive wire 14a, 14b ... Plate 15 ... gear 16: Gear head 17 ... Output shaft 20 ... Groove 21b ... Suction pole 21c ... Rotation excitation pole 21d ・ ・ ・ Blank pole 21e ... both ends 22 ... Motor 23 ... Base plate 26 ... gear 27 ... Cover

Continued front page    F-term (reference) 5H604 AA05 BB01 BB10 BB15 CC01                       CC05 CC16 QB11                 5H605 BB05 BB10 BB19 CC04 CC06                       EB15 EC01                 5H607 AA00 AA12 BB01 BB07 BB14                       BB17 CC01 CC03 DD03 EE31                       GG08 JJ06                 5H619 BB01 BB06 BB24 PP21 PP31                 5H621 BB07 BB10 GA01 GA04 HH01                       JK13 JK17 JK19

Claims (7)

[Claims] 1. A shaft-fixed motor, comprising: a stator having a cylindrical shaft; a bearing having the shaft inserted therein; and a rotor having a rotor rotatably supported about the shaft by the bearing. A fixed shaft motor, characterized in that a gear portion is provided on the outer surface of the rotor portion. 2. The shaft fixed motor according to claim 1, wherein the stator portion is composed of at least the shaft and an armature, and the armature has a plurality of salient poles. And a coil wound around the core, while the rotor portion has a yoke portion formed in a cylindrical shape in the axial direction of the shaft, and an inner cylindrical side surface of the yoke portion. And a bearing provided in openings at both ends of the yoke portion, the gear portion is integrally formed with the yoke portion on an outer surface of the yoke portion, and the shaft is The armature is housed in the yoke portion by being inserted into a bearing, the salient pole and the magnet are arranged so as to face each other, and the coil is supplied with electric power, so that the magnet A fixed shaft motor, wherein the rotor part and the gear part rotate relative to the stator part by magnetic attraction of the magnetic poles of the rotor to the salient poles. 3. The shaft fixed motor according to claim 1, wherein the stator portion is composed of at least the shaft and an armature, and the armature has a plurality of salient poles. And a coil wound around the core, while the rotor portion has a yoke portion formed in a cylindrical shape in the axial direction of the shaft, and an inner cylindrical side surface of the yoke portion. And a bearing provided in openings at both ends of the yoke portion, the gear portion is fitted and fixed on an outer surface of the yoke portion, and the shaft is provided inside the bearing. By being inserted, the armature is housed in the yoke portion, the salient poles and the magnet are arranged so as to face each other, the coil is supplied with power, and the magnetic pole of the magnet is A shaft fixed motor characterized in that the rotor portion and the gear portion rotate relative to the stator portion by being magnetically attracted to the salient poles. 4. The shaft fixed motor according to claim 1, wherein the stator portion is composed of at least the shaft and an armature, and the armature has a plurality of salient poles. , And a coil wound around the core, while the rotor portion has a reluctance rotor portion formed in a cylindrical shape in the axial direction of the shaft, and both ends of the reluctance rotor portion. Of the reluctance rotor part, the gear part is fitted and fixed on the outer surface of the reluctance rotor part, and the shaft is inserted into the bearing, whereby the reluctance of the armature is improved. Stored in the rotor portion, the salient poles and the inner cylindrical side surface of the reluctance rotor portion are arranged to face each other, and further by providing a notch in the outer surface, Sections having different reluctance generated between the salient poles are circumferentially divided on the outer side surface, and the magnetic flux generated in the salient poles when the coil is fed to the salient poles has a small reluctance. A shaft fixed motor, wherein the rotor portion and the gear portion rotate relative to the stator portion by magnetically attracting the partition to the salient poles. 5. The shaft fixed motor according to claim 2, wherein a slit portion is provided on a part of an outer peripheral surface of the shaft, and a ring is fitted around the slit portion. Insert the ring into the bearing,
Further, the fixed shaft motor is characterized in that a conductive wire for feeding power to the coil is housed in the slit portion, and the conductive wire is drawn out of the rotor portion. 6. The shaft fixed motor according to claim 2, wherein a ring is fitted to the shaft, a groove is provided on an inner peripheral surface of the ring, and the ring is inserted into the bearing. A shaft fixed motor characterized in that a conductive wire for supplying power to the coil is passed through the groove portion and pulled out to the outside of the rotor portion. 7. A gear head comprising a multi-stage gear and a plate that rotatably supports the gear, wherein both ends of the shaft are fixed to the plate, and A gear head characterized in that a shaft fixed type motor is incorporated inside.