JPS6330227Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the improvement of a small synchronous motor suitable for use as a drive source for timers and digital clocks.

[Conventional technology]

Generally, this type of synchronous motor has an N pole and an S pole on the circumference.
a rotor whose poles are alternately magnetized; a bottomed cylindrical stator box that pivotally supports one end of the rotor; a stator lid that pivotally supports the other end of the rotor and closes an open end of the stator box; The stator box includes a coil bobbin housed between the outer wall of the stator box and the rotor, and a plurality of stator pieces alternately stand up from the stator box and the stator lid between the inner peripheral surface of the coil bobbin and the rotor. A coil is wound around the body of the coil bobbin. When the coil is energized through a terminal provided on the coil bobbin, the rotor rotates due to the magnetic action between the stator and the rotor, and driving force is obtained.

However, since this type of synchronous motor is configured so that it can rotate in either direction at startup, it is necessary to provide some means to eliminate dead points at startup in order to rotate it only in one direction. Yes. For example, a certain number of stator pieces arranged at approximately the same pitch as the rotor pole pitch may be configured as main poles that regulate the position of the rotor in a stationary state, and a number of stator pieces may be arranged at positions that are out of phase with these main poles. Possible means include providing a plurality of commutating poles. In this case, in an undefined direction synchronous motor in which the rotation direction is not determined, a pair of commutative poles are arranged with their phases shifted in opposite directions, and another compensator that works together with the commutative poles to give forward and reverse rotation to the rotor. The provision of poles must also be considered.

[Problem that the invention attempts to solve]

However, in the case of small synchronous motors, the number of poles of the rotor or stator pieces is restricted due to the machinability of the stator pieces and the limit of the amount of magnetization of the rotor, and the operating range where starting torque is generated relative to the starting voltage becomes narrower. There was a problem that it became difficult to secure the

As a result of research and experiments, the problem is that despite the provision of additional commutating poles, the pair of commuting poles interfere with each other, resulting in a state in which the rotor cannot be rotated in either the forward or reverse direction, and as a result, the operating range It was revealed that this is due to the narrowing of the area.

[Means for solving problems]

In order to solve these problems, the present invention includes a rotor whose peripheral surface is alternately magnetized with N and S poles, a cylindrical stator box with a bottom that pivotally supports one end of the rotor, and a stator box. a stator lid that is assembled so as to close an opening of the stator box and pivotally supports the other end of the rotor, and a coil bobbin that is housed between the outer peripheral wall of the stator box and the rotor and has a coil wound around its body. , a synchronous motor having a plurality of stator pieces arranged alternately upright from a stator box and a stator lid so as to surround the periphery of the rotor, each stator piece being arranged in opposing positions and each having substantially the same pitch as the magnetic pole pitch of the rotor. A main pole consisting of three stator pieces each regulating the position of the rotor in a stationary state, and a main pole arranged between these main poles and positioned in opposite directions with respect to the center line of the rotor's magnetic pole pitch. A first commutative pole and a second commutative pole consisting of stator pieces of the same polarity arranged in a staggered manner; A third commutative pole consisting of stator pieces of different polarity that cooperate with the poles to regulate the rotational direction of the rotor is provided, and the stator pieces of the first commutative pole and the second commutative pole have different shapes. It is characterized by being formed by

[Effect]

According to the synchronous motor according to the present invention configured as described above, the mutual magnetic balance between the first commutative pole and the second commutative pole is disrupted, so that the magnetic force between the two commutative poles on the rotor is reduced. There is no electrical angle to cancel, and a situation where the rotor stops is prevented from occurring.

〔Example〕

The present invention will be explained in detail below with reference to embodiments shown in the drawings.

The synchronous motor 1 includes a stator box 2 formed of a magnetic material such as iron into a cylindrical shape with a bottom, and a bearing 3 press-fitted into a bearing hole provided at the center of the bottom plate.
One end of the rotor 4 is pivotally supported by. The rotor 4 consists of a rotor shaft 5, a rotor main body 6 fitted and fixed to the rotor shaft 5, and an annular magnet 7 fitted and fixed to the outer circumference of the rotor main body 6. N poles and S poles are alternately magnetized. Around the rotor 4, a plurality of stator pieces 8 formed by cutting and raising the bottom plate 2a of the stator box 2 in a rectangular shape in the radial direction are arranged in a cylindrical shape having a diameter slightly larger than the circumferential surface of the magnet 7. It is arranged so that there is no shape. Note that the details of the configuration, arrangement, etc. of the eight stator pieces will be described later.

Reference numeral 9 denotes a stator lid that closes the open end of the stator box 2, and is made of a magnetic material such as iron and has a substantially disc shape. A bearing 10 that pivotally supports the device is press-fitted and fixed, and a pair of attachment pieces 9a for attaching to the device fixing portion are integrally formed at two locations on the outer periphery. The stator lid 9 is provided with the same number of stator pieces 11 that are cut and raised in a rectangular shape in the radial direction in correspondence with the stator pieces 8, and the stator lid 9 closes the open end of the stator box 2. By assembling in this manner, the stator pieces 8, 11 are attached to the rotor 4.
arranged alternately around the In addition, stator piece 1
1 has a different polarity from the stator piece 8, and details of its configuration, arrangement, etc. will be described later. Furthermore, a notch 2b and a protrusion 9b are provided on the outer wall edge of the stator box 2 and the circumferential edge of the stator lid 9, which engage with each other in a press-fit state to fix the stator box 2 and the stator lid 9.

Reference numeral 12 denotes a synthetic resin coil bobbin consisting of flanges on both sides and a body part.A coil 13 is wound around the body part, and one of the flanges is connected to a terminal attachment part 18, which will be described later. A protrusion 14 is provided. Reference numeral 15 denotes a synthetic resin coil case which houses the coil bobbin 12 and serves to protect and insulate the coil 13, and has a pair of terminals 16 and 17 connected to both ends of the coil 13 on its outer wall. The terminal mounting portion 18 provided therein is provided in a protruding manner. The terminal mounting portion 18 is positioned and fixed by engaging with a notch 19 provided in the stator box 2 and engaging the protrusion 20 with the protrusion 14.

The structure and arrangement of the stator pieces 8 and 11 will be explained with reference to FIG. 2. FIG. 2 is a diagram illustrating the arrangement of the stator pieces 8 and 11 when the stator box 2 and stator lid 9 are combined. In this embodiment, the stator pieces 8 and 11 each have six poles each. It consists of a total of 12 stator pieces. The magnetic pole pitch of the magnet 7 of the rotor 4, which has a total of 16 poles alternately magnetized with N and S poles, is 360°/
16=22.5°. On the other hand, among the 12-pole stator pieces 8 and 11, three adjacent stator pieces 8a, 11a, 11b and 8b, 11c at opposing positions,
Reference numerals 11d constitute two sets of main poles that regulate the position of the rotor 4 in a stationary state. Each set of stator pieces 8a, 11a, 11b and 8b of these main poles,
11c and 11d have a pitch of 22.5°, which is almost the same as the magnetic pole pitch of the magnet, and the N and S poles are
The poles are arranged alternately. Further, among the remaining six stator pieces, the stator pieces on the stator box side indicated by reference numerals 8c and 8d constitute a first commutative pole A disposed opposite to each other, and both of them constitute the stator pieces 8a of the main pole. The polarity is the same and the entire circumference is the same.
The stator pieces 11a and 11c of the main pole are shifted by an angle α with respect to the center line S1 of the magnetic pole pitch of the rotor 4, which is divided into 16 equal parts. Further, the other stator pieces on the stator box side indicated by reference numerals 8e and 8f constitute a second commutative pole B disposed opposite to each other, have the same polarity as the first commutative pole A, and have the same polarity as the magnetic pole B. Pituchi center line S1 and
With respect to the magnetic pole pitch center line S2 forming an angle of 45 degrees, the angle β is the same as the angle α in the opposite direction to the first commutative pole A, that is, in the direction approaching the stator pieces 11b and 11d of the main pole.
They are placed at different positions. Also code 1
The stator pieces on the stator lid side indicated by 1e and 11f constitute a third commutative pole C disposed opposite to each other, and have opposite polarity to the first and second commutative poles A and B. With respect to the magnetic pole pitch center line S3 at the middle part of the commutator, angles α and β are made in the same direction as the first commutator A, that is, in a direction approaching this.
The position is shifted by an angle γ different from the .

The present invention is characterized in that each stator piece is arranged as described above, and the first commutative pole A and the second commutative pole B are formed with different shapes. That is, as shown in FIG. 1, the stator pieces 8c and 8d forming the first commutative pole A
The height dimension is made smaller than that of the stator pieces 8e and 8f that constitute the second commutating pole B by cutting the stator pieces 8e and 8f, which constitute the second commutating pole B, by cutting the stator pieces 8e and 8f from the tip to approximately the center. Therefore, the first commutative pole A has a weaker magnetic influence on the rotor 4 than the other commutative poles, in other words, the first commutative pole A and the second commutative pole B
It is constructed in such a way as to disrupt the magnetic balance between the two.

The example synchronous motor configured as above is
The rotor 4, whose position is regulated by one of the main poles in a stationary state, rotates by the magnetic action of each excited stator piece when the coil 13 is energized, but the direction of rotation is regulated. In addition to the first commutative pole A and the second commutative pole B, a third commutative pole C is provided, and the mutual magnetic balance of the first and second commutative poles B and C is disrupted. Therefore, there is no electrical angle to magnetically offset these, and the rotor 4 will not be in a dead center state where it cannot be rotated in either the forward or reverse direction.

FIG. 3 is a diagram showing the relationship between the height of the first commutative pole A and the starting voltage and hatching voltage based on experimental results, with the horizontal axis representing the height dimension (mm) of the first commutative pole A, and the vertical axis representing the height dimension (mm) of the first commutative pole A. Take the voltage V and show the change in starting voltage as a curve V1
The change in hatching voltage is shown by a curve V2. As is clear from the figure, when the height of the first commutative pole A is 6 mm like the other commutative poles B and C, the starting voltage is 50V, the hatching voltage is 130V, and the starting torque is generated. The operating range is 80V, but when the height is 2.5mm, the starting voltage is 40V and the hatching voltage is 150V.
The maximum operating range is 110V.

FIG. 4 shows another embodiment of the present invention, in which a stator piece 8 constituting the first commutative pole A is shown in FIG.
Although the electrodes c and 8d have the same height as the other commutating electrodes, they are cut up from the stator box 2 and then bent at their tips in a direction away from the rotor 4. By configuring the stator pieces 8c and 8d of the first commutative pole A in this way,
The magnetic influence on the rotor 4 is
Similarly to the first embodiment, the magnetic balance between the first commutative pole A and the second commutative pole B is disrupted, and the operating range in which starting torque is generated is expanded. FIG. ), the voltage V is plotted on the vertical axis, and the change in the starting voltage is shown by a curve V1, and the change in the hatching voltage is shown by a curve V2. As is clear from the figure, the stator piece 8 constituting the first commutative pole A
c and 8d are placed upright and have an inner diameter of 12.2 mm, the starting voltage V1 is 55V, the hatching voltage V2 is 135V, and the operating range is 80V. On the other hand, by gradually bending the stator pieces 8c and 8d outward, the operating area also becomes gradually wider.

It goes without saying that the same effect can be achieved by changing the surface area of the commutative electrode as another embodiment of the present invention.

[Effect of idea]

As explained in detail above, according to the present invention,
For each stator, there is a main pole consisting of three stator pieces arranged in opposing positions, each of which regulates the position of the rotor in a stationary state, each having approximately the same pitch as the rotor's magnetic pole pitch, and a space between these main poles. a first commutative pole and a second commutative pole consisting of stator pieces of the same polarity which are arranged in opposite directions with respect to the center line of the magnetic pole pitch of the rotor; a third commutative pole consisting of a stator piece of a different polarity which is arranged at a position shifted to one commutative pole side between the second commutative poles and works together with both commutative poles to regulate the rotational direction of the rotor; The stator pieces of the first commutative pole and the second commutative pole are formed to have different shapes so that their magnetic influence on the rotor is different, so that the rotor is It is possible to significantly reduce the probability of occurrence of a dead center that is not rotated in either the forward or reverse direction. Therefore, the rotor can be started more reliably, the starting torque and rotational stability are improved, the starting voltage is lowered and its variation is reduced, the hatching voltage is increased and its variation is reduced, and furthermore, A high-performance synchronous motor can be obtained, such as by expanding the operating range in which starting torque is generated.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing one embodiment of a synchronous motor according to the present invention, Fig. 2 is an explanatory diagram of the arrangement of stator pieces, and Fig. 3 is an illustration of the height dimension and voltage of the first commutative pole. Diagrams explaining the relationship, FIG. 4 shows another embodiment, FIG. FIG. 3 is a diagram illustrating the relationship between and voltage. 1...Synchronous motor, 4...Rotor, 8...Stator, 9...Stator lid, 8a, 11a, 11
b, 8b, 11c, 11d...main pole, 8c, 8d
...Stator piece of the first commutative pole, 8e, 8f...Stator piece of the second commutative pole, 11e, 11f...Third
Stator piece of commutating pole, 12... Coil bobbin, 1
3... Coil, S1, S2, S3... Center line of magnetic pole pitch.

Claims (1)

[Scope of utility model registration request] A rotor 4 having N and S poles alternately magnetized on its circumferential surface, a stator box 2 having a cylindrical shape with a bottom that pivotally supports one end of the rotor, and an opening of the stator box so as to be closed. A stator lid 9 that is assembled and pivotally supports the other end of the rotor, and a coil bobbin 12 that is housed between the outer peripheral wall of the stator box and the rotor and has a coil 13 wound around its body.
and a plurality of stator pieces 8, 11 which are arranged alternately upright from the stator box and stator lid so as to surround the periphery of the rotor. Three stator pieces 8a, 11a, 11b and 8b, 11c, 11 that regulate the position of the rotor in a stationary state with approximately the same pitch.
d, and stator pieces 8c and 8d of the same polarity arranged between these main poles and shifted in opposite directions with respect to the center line of the magnetic pole pitch of the rotor. The first consisting of
A second commutative pole consisting of a commutative pole and stator pieces 8e and 8f, and a second commutative pole disposed between the first and second commutative poles at a position shifted to one commutative pole side and working together with both commutative poles to rotate the rotor. A third commutative pole consisting of stator pieces 11e and 11f of different polarity for regulating the rotational direction of the rotor is provided, and the first commutative pole and the second commutative pole have different magnetic influences on the rotor. Synchronous motors are characterized by having different shapes.