JPH10161752A - Deceleration transmitting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deceleration transmitting method which drives the rotary shaft of a device to be rotated at a minimum speed, invariably, stably, and with high rotating precision without using any fly-wheel. SOLUTION: In a deceleration transmitting method decelerating the rotation of a motor 1 to a minimum speed slower than 10 rotations per minute by a decelerator 3 to transmit to the rotary shaft 12 of the device to be moved 11, the decelerator 3 is made a traction driving system, the motor 1 is made a variable speed system, the rotary shaft 5 of the motor 1 is incorporated as the input element 8 of the decelerator the decelerator 3 and the rotary shaft 12 of the device to be moved 11 is connected directly with the output element 9 of the decelerator 3 to adjust the rotation speed of a rotary shaft of the motor 1 in order that the detected value of the rotation speed at the shaft 12 of the device 11 is always held to be a set value by feedback control. Therefore, rotation irregularity coused at the rotary shaft 12 of the device 11 by a transmitting error on working precision and assembling precision of a transmission system from the motor 1 to the device 11 and external diffusion including the fluctuation of a load at the device 11 is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus such as a printing machine, a printer or a photo processor, which is used at an extremely low speed of 10 revolutions per minute or less and requires high rotational accuracy and excellent rotational stability. The present invention relates to a deceleration transmission method suitably used for driving a rotating unit in a machine, a film processing machine, a sound recording device, or the like.

[0002]

2. Description of the Related Art Conventionally, as the above-mentioned deceleration transmission method, a method in which the rotation of an electric motor controlled at a constant speed is reduced by a gear type speed reducer and transmitted to a rotating shaft of a driven device has been adopted. In the gear type speed reducer, a reliable deceleration transmission with less slippage can be obtained, but the output side gear has a delicate change in angular velocity due to the meshing between the gears and the processing accuracy of the gears, and the rotation of the driven device. Uneven rotation will occur on the shaft.

In the case where the driven device is an image processing machine such as a printing press or a printer, and the rotation unevenness occurs on the rotating shaft of a paper or photosensitive paper printing drum, the image is transferred onto the paper or photosensitive paper. When color shift or stripe pattern occurs in the image, and when the driven device is a film processing machine and the rotation unevenness occurs on the rotation axis of the film feed roll, the thickness of the obtained film becomes uneven. Further, when the driven device is a recording / recording device and the rotation unevenness occurs on the rotation axis of a recording medium such as a tape or a disc, various noises are generated when recording is reproduced from the recording medium.

[0004] Therefore, in the reduction transmission method using a gear type reduction gear, in order to reduce the rotation unevenness,
Conventionally, a method has been adopted in which a flywheel is coupled coaxially with the rotating shaft of the driven device, and the angular velocity change in the output gear is absorbed by the moment of inertia of the flywheel.

FIG. 2 is a side view of a main part including a partial cross-sectional view of a device including a speed reducer and a driven device illustrating the speed reduction transmission method according to the prior art. In FIG. Is rotated at a constant speed by the control device 34 so that the detected value of the rotation speed by the rotation sensor 33 provided in the motor 31 becomes a set value. The output element 36 of the machine 35 and the rotating shaft 12 of the driven device 11
The flywheel 38 is fixed to the rotating shaft 12 of the driven device 11 coaxially with the rotating shaft 12 by a set screw 39.

However, in order to stably rotate the flywheel at an extremely low speed of 10 revolutions per minute or less to reduce rotational unevenness on the rotating shaft of the driven device, the weight and the radius of rotation of the flywheel should be as small as possible. Although it is necessary to increase the size and the radius of rotation of the flywheel, the size and weight of the entire device must be increased,
In particular, when the driven device requires an operation that repeatedly starts and stops frequently, a large amount of energy and time is wasted at each start and stop, resulting in reduced workability and efficiency. When delicate speed control is required as described above, problems such as deterioration of control responsiveness due to a large inertial load of the flywheel occur.

After all, even if the flywheel is connected to the rotating shaft of the driven device in the reduction transmission method using the gear type reduction gear, the range of the weight and the turning radius that can be adopted in the flywheel is limited to the range of the rotating shaft of the driven device. It is difficult to reduce the occurrence of subtle rotational unevenness to an unacceptable level, and it has been difficult to respond to the recent technical demand for high rotational accuracy.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a deceleration that can drive a rotating shaft of a driven device stably at a very low speed without unevenness and with high rotational accuracy without using a flywheel at all. It is to provide a transmission method.

[0009]

SUMMARY OF THE INVENTION A deceleration transmission method according to the present invention is a deceleration method in which the rotation of an electric motor is reduced to an extremely low speed of 10 revolutions per minute or less by a speed reducer and transmitted to a rotating shaft of a driven device. In the transmission method, the speed reducer is a traction drive type, the motor is a variable speed type, and the rotating shaft of the motor is incorporated as an input element of the speed reducer, and the rotating shaft of the driven device is directly connected to the output element of the speed reducer, and the feedback is performed. By controlling the rotation speed of the rotating shaft of the electric motor so that the detected value of the rotating speed of the rotating shaft of the driven device is always maintained at the set value, the processing accuracy in the transmission system from the motor to the driven device is thereby improved. In addition, it is possible to eliminate rotational unevenness that occurs on a rotating shaft of a driven device due to a transmission error in assembling accuracy and a disturbance including a load variation in the driven device. It is characterized by a door.

In the above configuration, a traction drive type is adopted as the speed reducer instead of the conventional gear type, thereby preventing the occurrence of the angular velocity change specific to the gear type on the output side and smooth transmission. Done. In addition, a variable speed type is adopted for the motor in place of the conventional constant speed rotation type, whereby the rotation speed of the rotation shaft of the motor is controlled by feedback control of the rotation shaft of the driven device to maintain the rotation speed at a predetermined speed. It becomes possible to adjust.

[0011] In the control system, unevenness in rotation of the rotating shaft of the driven device may occur due to a transmission error in processing accuracy and assembling accuracy in the transmission system from the electric motor to the driven device and a disturbance including a load variation in the driven device. Since such rotational unevenness also appears as a deviation between the detected value and the set value of the rotational speed at the rotating shaft of the driven device, it is eliminated by the feedback control of the rotating shaft of the driven device.

According to the structure of the present invention, the rotating shaft of the electric motor is incorporated as an input element of the speed reducer, and the rotating shaft of the driven device is directly connected to the output element of the speed reducer. In addition, transmission errors between the transmission members are reduced, and it becomes easier to eliminate rotational unevenness occurring on the rotation shaft of the driven device in the control system.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on embodiments shown in the drawings. FIG. 1 is a side sectional view of a device including a speed reducer and a driven device illustrating a speed reduction transmission method according to an embodiment of the present invention.

In FIG. 1, a frame 2 of an electric motor 1 is integrated with a case 4 of a traction drive type reduction gear 3, and a rotating shaft 5 of the electric motor 1 is supported on the frame 2 at a rear end side thereof via a rolling bearing 6. The rotary shaft 5 is inserted into the case 4 via a seal 7 on the front end side, and the rotating shaft 5 is used as an input element 8 of the speed reducer 3.

An output element 9 composed of a boss member is supported on the case 4 via a sliding bearing 10 on the same axis as the rotary shaft 5 of the electric motor 1, and is coaxial with the output element 9 on the rotary shaft of the driven device 11. 12 is fitted and set screw 13
, And a planetary transmission mechanism 21 is interposed between the rotation shaft 5 (input element 8) and the output element 9 of the electric motor 1.

Further, a slit disk 16 and a photoelectric sensor unit 17 of a rotary encoder 15 as a rotation sensor are provided on the rotation shaft 12 and the case 14 of the driven device 11, respectively.
The control unit 18 compares the detected value of the rotational speed by the photoelectric sensor unit 17 with the set value, and inputs a required control signal to the electric motor 1 so that the deviation is eliminated.

The planetary transmission mechanism 21 includes a sun roller 22 formed on the front end side of the rotating shaft 5 of the electric motor 1, a track ring 23 internally fixed to the case 4 of the speed reducer 3, and around the sun roller 22. The solar rollers 22 are arranged at an angular interval.
A plurality of planetary rollers 24 (only one is shown in FIG. 1) circumscribed and also inscribed in the race ring 23, and a planetary shaft 26 supporting each planetary roller 24 via a bearing 25.
And a carrier 27 that supports each planetary shaft 26 and is integrated with the output element 9. In this case, the motor 1
The rotary shaft 5 is formed on the sun roller 22 at the front end side thereof and has a plurality of planetary rollers 24 and the orbit ring 2.
The case 4 is supported by a kind of bearing mechanism composed of 3 or the like.

Further, each planetary roller 24 is provided with a sun roller 2.
2 is composed of a large-diameter flat cylindrical roller portion 24a that is short in the axial direction and a small-diameter truncated cone-shaped roller portion 24b formed on both sides thereof and tapered outward in both directions. A fixing ring 23a having a conical inner peripheral surface that is internally fixed to the case 4 and is inscribed in the outer peripheral surface of one frustoconical roller portion 24b of each planetary roller 24.
A movable ring having a conical inner peripheral surface that is disposed so as to be displaceable in the axial direction and faces the fixed ring portion 23a and that is inscribed in the outer peripheral surface of the other frustoconical roller portion 24b of each planetary roller 24; 23b. Also,
The compression coil spring 28 for pressing the movable ring portion 23b in the direction of the fixed ring portion 23a includes the movable ring portion 23b and the case 4.
It is interposed between and.

In the above configuration, the rotation input from the rotary shaft 5 of the electric motor 1 also serving as the input element 8 is reduced to an extremely low speed of 10 rotations per minute or less via the planetary transmission mechanism 21 and the output element 9 is rotated. Of the driven device 11 via the
2 is transmitted. In that case, the rotating shaft 1 of the driven device 11
The rotation speed of the rotary shaft 5 of the electric motor 1 is adjusted by the control device 18 so that the motor 2 is maintained at a predetermined extremely low speed while the feedback control of the motor 2 is performed. I do.

In the above configuration, in the planetary transmission mechanism 21, the compression coil spring 28 applies a pressing force between the transmission members in the planetary transmission mechanism 21 as a normal force generating means.

[0021]

The deceleration transmission method according to the present invention is constructed as described above, so that the rotating shaft of the driven device can be rotated at an extremely low speed without using a flywheel at all, with stable and high rotational accuracy. The apparatus can be driven to rotate, and the flywheel can be removed from the driven apparatus, so that the entire apparatus can be reduced in size and measured.

[Brief description of the drawings]

FIG. 1 is a side cross-sectional view of a device including a speed reducer and a driven device illustrating a speed reduction transmission method according to an embodiment of the present invention.

FIG. 2 is a main part side view including a partial cross-sectional view of a device including a speed reducer and a driven device, illustrating a speed reduction transmission method according to the related art.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 motor 3 reduction gear 5 rotating shaft (motor) 8 input element 9 output element 11 driven device 12 rotating shaft (driven device)

Claims (1)

[Claims] 1. A speed reduction transmission method in which the rotation of an electric motor is reduced to an extremely low speed of 10 rotations per minute or less by a speed reducer and transmitted to a rotating shaft of a driven device. Making the motor a variable speed type, and incorporating the rotating shaft of the motor as an input element of the speed reducer, and directly connecting the rotating shaft of the driven device to the output element of the speed reducer,
The rotational speed of the rotating shaft of the electric motor is adjusted so that the detected value of the rotating speed of the rotating shaft of the driven device is always maintained at the set value by the feedback control, and thereby, the machining accuracy in the transmission system from the electric motor to the driven device. A deceleration transmission method characterized by eliminating uneven rotation occurring on a rotating shaft of a driven device due to a transmission error on the upper and assembling accuracy and a disturbance including a load variation in the driven device.