JPH04127853A - Motor - Google Patents

Abstract

PURPOSE:To realize arbitrary modification of the dimension and the profile of an output shaft by employing a hollow output shaft for taking out the rotational force of the rotor of a motor. CONSTITUTION:A motor comprises a stator 31 secured to a casing 31, a rotor 34 producing rotational force from a magnetic force produced between the stator 31 and the rotor 34, and a hollow output shaft 35 supported by bearings 33, 33' and taking out the rotational force of the rotor 34. The hollow output shaft 35 may have various profiles including the cylindrical hole as shown on the drawing. Since the output shaft is made hollow, dimension and profile of the output shaft can be modified arbitrarily by fitting a shaft having arbitrary profile and dimension therein.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a motor, and more specifically to the shape of an output shaft.
This invention relates to a motor whose dimensions can be easily changed.

<Background of the Invention> FIG. 15 shows a schematic structure of a conventional DC motor, and FIG. 16 shows a schematic structure of a conventional stepping motor.

As shown in these figures, the output shaft 15.25 is rod-shaped, and a rotor is fixed to the output shaft 15.25.

In addition, a pulley and a gear are attached to this output shaft 15.25.

Attach and use transmission parts such as clutches and screws.

<Problems to be Solved by the Invention> Due to the above configuration, when the dimensions of the output shaft 15.25 are changed, it is not possible to change only the output shaft 15.25, and the rotor 14 It became necessary to rebuild the entire ゜24. For this reason, even a slight change in specifications will increase manufacturing costs.

There were some problems, such as the length of time it took to complete the project.

The present invention has been made to solve the above problems, and its purpose is to realize a motor in which one dimension of the output shaft can be freely changed.

Means for Solving the Problems> The first configuration for solving the above problems consists of a stator fixed to an outer case, a rotor that generates rotational force by the magnetic force generated between the stator, and a bearing. The motor is supported by a rotor and includes an output shaft for extracting the rotational force of the rotor to the outside, and is characterized in that the output shaft is hollow.

A second configuration for solving the above-mentioned problems includes a stator fixed to an outer case, a rotor that generates rotational force by the magnetic force generated between the stator, and a rotor supported by a bearing. A motor equipped with an output shaft for extracting rotational force to the outside, the output shaft for extracting the rotational force of a rotor of the motor to the outside is configured to be hollow, and a female thread is formed on the inner surface of the output shaft. It is characterized by:

In the motor of the first configuration, the output shaft is hollow, so by fitting a shaft of any shape and size into this hollow part, the size and shape of the output shaft can be changed as desired. It can be easily changed.

In the motor of the second configuration, since a female thread is formed in the hollow portion of the output shaft, an output shaft of any length can be obtained by inserting a shaft having a male thread formed on the surface.

<Examples> Examples of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a configuration diagram showing a schematic cross-sectional configuration of an embodiment of the present invention. Here, the case where it is applied to a stepping motor will be explained.

In this figure, 31 is a case that constitutes the outer case of the motor, 32 is a coil that constitutes the stator of the motor, 33 and 3.
3' is a bearing that receives the output shaft of the rotor, 34 is a rotor, 3
5 is a hollow output shaft whose inside is hollow, and 36 is a yoke.

2 to 7 are explanatory diagrams showing examples of the cross-sectional shape of the hollow output shaft 35. FIG. As shown in these figures, the hollow portion of the hollow output shaft 35 may have various shapes other than a cylindrical hole.

Here, a case where the inner surface of the hollow output shaft 35 is female threaded as shown in FIG. 7 will be described with reference to FIG. 8.

A shaft 37 having a male thread formed on its surface is fitted into a hollow output shaft 36 whose inner surface is formed with a female thread. In this case, the length of the shaft 37 is determined so that the length of the shaft extending outside the motor is the required length. Further, in this case, the shaft 37 and the hollow output shaft 36 can be fixed by sandwiching the hollow output shaft 36 between the nuts 38 and 39. In such a case, the shaft extension dimension can be adjusted to any desired length, so the problems that occur in the conventional case do not occur. In addition, since the shaft 37 penetrates the inside of the hollow output shaft 36 and is integrated with the hollow output shaft 36,
There are no problems in terms of strength and balance. Therefore, compared to a conventional motor in which the output shaft is extended using a joint, the motor of this embodiment is particularly superior in terms of strength and balance. In addition, the ability to finely adjust the shaft extension dimension is particularly excellent.

Further, as shown in FIG. 9, the shaft 41 is inserted into the hollow output shaft 40, and the fixing screw 42.
It is also possible to fix it with 43.

In this case as well, the same effect as in FIG. 8 can be obtained.

In FIG. 10, a gap is provided between the hollow output shaft 44 and the shaft 45 to put them in a loose insertion state, and a viscous fluid 46 is sealed in the gap. Note that oil seals 47 and 48 are installed to prevent the viscous fluid 46 from leaking. For such a configuration,
The rotational torque of the hollow output shaft 44 is transmitted to the shaft 45 via the viscous shear force of the viscous fluid. The viscous shearing force in this case is proportional to the rotational speed of the hollow output shaft 44, so when the rotational speed of the hollow output shaft 44 is low, the torque of the shaft is small, and as the rotational speed of the hollow output shaft 44 increases, the torque of the shaft 45 is small. Torque also increases.

Therefore, the same effect as forming a continuous torque clutch within the motor can be obtained.

In FIG. 11, an elastic body 50 is interposed between the hollow output shaft 44 and the shaft 49, and this elastic body 50 is bonded to the hollow output shaft 44. Therefore, some slippage occurs between the hollow output shaft 44 and the shaft 49. Therefore,
When the rotation of the hollow output shaft 44 increases rapidly, the rotation of the shaft 49 smoothly increases with the phase being delayed.

This has the advantage that shocks caused by changes in the motor's rotational speed are not transmitted to the external load.

In this case, the same effect as having a shock absorber built into the motor can be obtained.

FIG. 12 shows an embodiment in which the motor according to the present invention is applied to driving a lens. In this figure, A of the hollow output shaft 70
The inner surface of the portion is circular, and the inner surface of portion B is any shape other than a circle. Further, the shaft 74 has a male screw thread at the C portion, and the same shape as the B portion of the hollow output shaft 70 at the D portion. And A
and C are radially fitted, and B and D are also fitted. Also, lens barrel 7
A female threaded portion 71a provided in a portion of the shaft 71 and the shaft 71 are spring-fitted. Lens frame 73 with lens 72
is configured to be movable in the axial direction while being supported by guide pins 77 and 77', and the lens is controlled by the biasing force of the spring 75 and the movement of the shaft 74 in the axial direction.

When the motor is driven, as the hollow output shaft 70 rotates, the shaft 74 also rotates in accordance with the rotation of the hollow output shaft 70 due to the fitting between the B section of the hollow output shaft 70 and the D section of the shaft 74. The rotation of this shaft 74 and the female threaded portion 71
Due to the action of the shaft 74, the shaft 74 is rotated and pulled out or pulled in the axial direction. When the shaft 74 is extended, the lens frame 73 is extended, and when the shaft 74 is retracted, the lens frame 73 is also retracted by the biasing force of the spring 75. The amount of lens movement at this time is the spring 7
9, the operating knob is detected by a change in the resistance value of the slide volume 78 held down at one end of the shaft. Note that the difference between the biasing force of the spring 79 and the biasing force of the spring 75 needs to be larger than the total weight of the lens 72 and the lens frame 73, and this force causes the 0 part of the shaft 74 and the female threaded part 71a to It absorbs the backlash that occurs between the two. Note that the hole in the A section of the hollow output shaft 70 may have any shape as long as the 0 section of the shaft 74 can freely rotate.

Further, FIG. 13 shows another example. Here, a female thread is formed on the inner surface of the hole of the hollow output shaft 80. Further, a male thread is formed on the motor side of the shaft 84. Then, the lens side of the shaft 84 (arbitrary cross-sectional shape part 84a
) is formed to have a cross section of any shape other than a circle,
A rotation restricting portion 81g having a hole with the same cross-section shape allows movement only in the axial direction. Further, since the shaft 84 does not rotate, the lens frame 83 and the knob of the slide volume 88 are fixed to the shaft 84.

Here, when the hollow output shaft 80 rotates, the shaft 84 is pulled out or pulled in.

Furthermore, as shown in FIG. 14, by providing strength to the shaft 94, the guide pin can be omitted.

Incidentally, the motor having the hollow output shaft described in the above embodiments can be applied to various types of electric motors, regardless of whether they are direct current or alternating current.

<Effects of the Invention> As explained in detail above, in the first configuration of the present invention,
It is equipped with a stator fixed to an outer case, a rotor that generates rotational force by the magnetic force generated between the stator, and an output shaft that is supported by a bearing and extracts the rotational force of the rotor to the outside. A motor with a hollow output shaft. In a motor with this configuration, the output shaft is hollow, so by fitting a shaft of any shape and size into this hollow part, the dimensions and shape of the output shaft can be easily changed. can.

Further, in the second configuration of the present invention, a stator fixed to an outer case, a rotor that generates a rotational force by a magnetic force generated between the stator, and a rotor that is supported by a bearing and generates a rotational force of rotation r. The motor is equipped with an output shaft for taking out the rotational force of a rotor of the motor to the outside, the output shaft for taking out the rotational force of the rotor of the motor to the outside, and having a hollow structure, and a female thread formed on the inner surface of the output shaft. In a motor with this configuration, since a female thread is formed in the hollow portion of the output shaft, the output shaft can be made to have an arbitrary length by inserting a shaft having a male thread formed on the surface.

As a result, according to the present invention, it is possible to realize a motor having an output shaft having an arbitrary shape and one dimension, and it is also possible to change the dimensions of the output shaft.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing the configuration of a motor according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing the cross-sectional shape of the output shaft of the motor according to the embodiment shown in FIG. 1, and FIG. 4 is a cross-sectional view showing the cross-sectional shape of the output shaft of the motor of the example shown in FIG. 1; FIG. 6 is a cross-sectional view showing the cross-sectional shape of the output shaft of the motor in the example shown in FIG. 1; FIG. A cross-sectional view showing the cross-sectional shape of the output shaft of the motor of the embodiment shown in the figure, FIG. 8 is a configuration diagram showing the configuration of another embodiment of the present invention, and FIG. 9 is a configuration diagram of another embodiment of the present invention. FIG. 10 is a configuration diagram showing the configuration of another embodiment of the present invention. FIG. 11 is a configuration diagram showing the configuration of another embodiment of the present invention. FIG. 12 is a configuration diagram showing the configuration of another embodiment of the present invention. FIG. 13 is a block diagram showing the structure when the motor of the embodiment of the present invention is applied to a lens drive motor; FIG. Fig. 14 is a block diagram showing the structure when the motor of still another embodiment of the present invention is applied to a lens drive motor, Fig. 15 is a block diagram showing the structure of a conventional DC motor, and Fig. 16 is a conventional stepping motor. FIG. 2 is a configuration diagram showing the configuration of a motor.

Claims (2)

[Claims] (1) A stator fixed to an outer case, a rotor that generates rotational force by the magnetic force generated between the stator, and an output shaft that is supported by a bearing and extracts the rotational force of the rotor to the outside. 1. A motor having a hollow output shaft. (2) A stator fixed to the outer case, a rotor that generates rotational force by the magnetic force generated between the stator, and an output shaft that is supported by a bearing and extracts the rotational force of the rotor to the outside. 1. A motor comprising: an output shaft for extracting the rotational force of a rotor of the motor to the outside; the output shaft is hollow; and an internal thread is formed on the inner surface of the output shaft.