JP4366041B2 - Rotation drive - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotary drive device, and more particularly to a rotary drive device that can rotate a photosensitive drum or the like of a copying machine with low speed and high accuracy, and can detect an output rotational speed and feedback control the drive rotational speed.
[0002]
[Prior art]
In an image forming apparatus such as a copying machine, a printing machine, or the like, a rotation driving device for rotating a roller for feeding a photosensitive drum or a film with low speed and high accuracy is required. A conventional device of this type includes a motor and a planetary reduction device that reduces the rotation of the motor. The planetary reduction device includes a gear reduction device and a traction or friction transmission reduction device, each having a solar wheel, an internal ring, a planetary vehicle, and a carrier.
[0003]
The traction type speed reducer is configured to frictionally transmit torque by pressing the solar wheel, the internal ring, and the planetary wheel together. The solar wheel, the internal ring, and the planetary wheel are each mainly made of an iron-based material.
In such a conventional traction type reduction gear, each friction contact portion of the solar wheel, the internal ring, and the planetary wheel is configured to transmit torque via traction oil such as grease. This prevents the seizure of iron and the like, or increases the torque transmission force between ferrous materials.
[0004]
[Problems to be solved by the invention]
In the conventional traction type reduction gear as described above, traction oil is filled in the reduction gear, and thus a seal member or the like is required to prevent the oil from leaking out. In addition, the surface with which the seal member abuts must be finished with high accuracy.
[0005]
Furthermore, in order to obtain high rotational accuracy, it is necessary to process the friction contact portions of the solar wheel, the internal ring, and the planetary vehicle with high accuracy, and high assembling accuracy is required, which increases the manufacturing cost. .
An object of the present invention is mainly to reduce manufacturing costs.
Another object of the present invention is to reduce the manufacturing cost and improve the transmission efficiency.
[0006]
[Means for Solving the Problems]
  The rotary drive device according to claim 1 is:A motor as a rotational drive source, and a speed reducer having a friction transmission unit that receives the rotation of the motor and transmits torque by frictional contact of one or more rotating members, and decelerates and outputs the rotation from the motor And a speed detection mechanism for detecting the output rotational speed of the reduction gear, and at least one member among the members that transmits torque by the friction transmission constitutes a portion other than the friction contact portion. And a rubber member constituting the friction contact portion, the rubber of the rubber member is elastically deformed without moving the member having the rubber member and the other member in contact with the rubber, It is characterized by being provided in pressure contact with another member in contact with the rubber.
[0007]
  In this device, the rotation of the motor is decelerated and output by the reduction device, and the driven device is driven. At this time, in the speed reducer, torque transmission is performed at least in part by frictional contact of the rotating member. Configure the friction transmission partPartAt least one of the materialsParts ofIs a rubber made of structure and rubberAppendixMaterial, rubber is the opponentPart ofTorque is transmitted in contact with the material. At this time, rotation accuracy deteriorates due to frictional contact of rubber. However, in this device, the output rotational speed of the reduction gear is detected, and the rotational speed of the motor is feedback-controlled based on the detection result so that the output rotational speed becomes a desired set speed. Therefore, a desired output rotational speed can be obtained with high accuracy in spite of torque transmission due to rubber contact.
[0008]
  Here, the friction transmission partPartThe material is composed of a structure and rubber, and the rubber is in frictional contact to transmit torque. Therefore, the friction coefficient can be increased as compared with a rotating member made of a conventional iron-based material, and there is no need to increase the processing accuracy, and no lubricant is required. Therefore, the manufacturing cost can be reduced and the pressing force of the frictional contact portion can be reduced. In particular, in the differential planetary system, it is possible to eliminate the urging member for pressing the internal ring against the planetary car. It becomes. Thus, for example, when the speed reducer is divided into a friction transmission portion and a gear transmission portion, the traction oil as in the conventional device is not required in the friction transmission portion, and a seal member is not required. At the same time, high-precision processing of the mating member with which the seal member comes into contact is also unnecessary. In addition, even if a part of the transmission includes a gear meshing part, if only that part is formed of a resin or the like impregnated with a lubricant, traction oil is not necessary, and all members are lubricated as described above. Compared with the case where the resin is impregnated with resin, the manufacturing cost is reduced.
[0009]
  Also, DepartmentSince the portion other than the frictional contact portion of the material is formed of a structure, the strength of the structure is not increased, so that the strength is not insufficient. Further, since processing errors and assembly errors of the rotating member can be absorbed by elastic deformation of the rubber, options for processing accuracy, processing method, and material of the rotating member are expanded. As a result, manufacturing costs can be reduced..
[0010]
Here, when the speed detection mechanism is arranged inside the speed reduction device to reduce the axial dimension, the conventional device has to separate the portion where the speed detection mechanism is provided from the speed reduction mechanism portion filled with oil. It was. However, in this device, as described above, it is possible to eliminate the need for oil in the speed reduction mechanism. In this case, there is no member for isolating this portion even if the speed detection mechanism is arranged inside the speed reduction device. This eliminates the need for a smaller device and simplifies the configuration.
[0011]
  RubberAppendixWhen using materials in multiple locations, it may be possible to vary the elastic body or structure depending on where it is used.Yes.
[0013]
  ContractClaim2The rotary drive device according to claim1'sIn the apparatus, the structure has a groove on the entire outer periphery, and rubber is mounted in the groove. Here, various rubbers can be selected according to the specifications and can be easily attached to the structure. Therefore, rubber with various characteristics while using a common structureAppendixThe material can be easily realized.
[0014]
  Claim3The rotational drive device according to claim 1Or 2In this apparatus, the rubber is provided integrally with the structure on the outer peripheral surface of the structure. Here, “integral” means provided by adhesion, coating, or the like. In this case rubberAppendixThe processing of the material becomes easy. Claim4The rotary drive device according to claim 1 is from3In any of the apparatuses, the structure is a resin molded product.
[0017]
  Claim5The rotary drive device according to claimAny one of 1 to 4In this device, the speed reducer isThe rotation transmission unit includes at least two rotation transmission units, and the at least two rotation transmission units include a rotation transmission unit based on frictional contact of a rubber member and a rotation transmission unit based on meshing of a gear.A sun gear provided at the tip of the rotating shaft of the motor and having teeth formed on the outer periphery, and a plurality of planetary gears having teeth that mesh with the sun gear on the outer periphery;The rotation transmission part by frictional contact of the rubber-equipped member isAn internal ring disposed concentrically with the sun gear, and a plurality of planetary rollers that are in frictional contact with the internal ring and are non-rotatable with the planetary gear,HaveAt least one of the star roller and the internal ring is rubberAppendixIt is a material.
[0018]
In this device, the speed reducer is constituted by a planetary system, and the rotation of the motor is input to the sun gear, and this rotation is transmitted to the planetary gear meshing with the sun gear. In the speed reduction mechanism, the planetary gear and the planetary roller are provided so as not to rotate relative to each other, and the planetary roller is in frictional contact with the internal ring. Therefore, the rotation of the sun gear is decelerated by the reduction mechanism and output from the carrier.
[0019]
In such a planetary reduction device, in addition to the same effects as described above, the sun gear and the planetary gear are engaged and transmitted by teeth, so that rotation is transmitted efficiently. In addition, although the speed fluctuation occurs due to the meshing of the sun gear and the planetary gear, the speed fluctuation generated here is provided in the friction contact portion between the planetary roller on the output side and the internal ring.RubberTherefore, it is possible to make it difficult to transmit the speed fluctuation to the output side.
[0025]
In this case, the same effect as described above can be obtained.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
[First Embodiment]
FIG. 1 shows a rotary drive device according to a first embodiment of the present invention.
The rotational drive device shown in FIG. 1 includes a motor 1, a planetary reduction device 2 that decelerates and outputs rotation from the motor 1, and a speed detection mechanism 3 for detecting the output rotational speed of the reduction device 2. And. The rotary drive device further includes a controller 4 to which an output from the speed detection mechanism 3 is input, and a drive device 5 that controls the rotational speed of the motor 1 in accordance with a control signal from the controller 4.
[0027]
The motor 1 includes a cup-shaped rotor hub 10, a rotor magnet 11 fixed to the inner wall of the rotor hub 10, a bracket 12 disposed at the center, a coil 13 disposed between the rotor magnet 11 and the bracket 12, And a rotating shaft 14. The bracket 12 includes a cylindrical bearing holder portion 15 and a motor flange 16 formed so as to extend radially outward at the output side end portion (left end portion in FIG. 1) of the bearing holder portion 15. Have. The rotating shaft 14 is rotatably supported on the inner peripheral portion of the bearing holder portion 15 via bearings 17 and 18 such as a pair of ball bearings. Further, the tip end of the rotating shaft 14 enters the speed reduction device 2 to constitute a sun gear 20 that is an input portion of the speed reduction device 2. On the outer ring of the bearing 17 on the speed reducer 2 side, a spring 19 for applying preload to both the bearings 17 and 18 is provided.
[0028]
The reduction gear 2 has a differential planetary mechanism that reduces the rotation of the motor 1 to, for example, about 1 rotation / second, and includes a sun gear 20, an internal ring 21, and a plurality (three in this embodiment). (Only two of them are shown in the figure), planetary gears 22 and planetary rollers 23, carriers 24 that rotatably support the planetary gears 22 and planetary rollers 23, and an output shaft 25. Yes. The sun gear 20, the internal ring 21, the plurality of planetary gears 22, the planetary roller 23, and the carrier 24 are accommodated in a housing 26. A hole through which the output shaft 25 passes is formed on the end surface of the housing 26 opposite to the motor, and the output shaft 25 is rotatably supported by the housing 26 via a pair of bearings 27 and 28.
[0029]
The sun gear 20 is a spur gear with teeth formed on the outer periphery, and is integrally formed at the tip of the rotating shaft 14.
As shown in an enlarged view in FIG. 2, the internal ring 21 has an annular fixed ring 21a and a movable ring 21b, and both the rings 21a and 21b are provided to face each other with the planetary gear 22 interposed therebetween. It has been. The fixing ring 21 a is fixed to the housing 26 so as not to move in the axial direction and the rotational direction. The movable ring 21b is attached to the housing 26 so as to be movable in the axial direction and not to be relatively rotatable. And the surface which the inner peripheral part of both the rings 21a and 21b opposes is formed in the taper shape, respectively.
[0030]
The planetary gear 22 and the planetary roller 23 are integrally formed except for an elastic body, which will be described later, and a hole is formed at the center. The planetary gear 22 and the planetary roller 23 are supported in a cantilevered manner with respect to the carrier 24 by a rod 29 inserted into the hole.
The planetary gear 22 is a spur gear having teeth formed on the outer periphery, and meshes with the sun gear 20. The planetary roller 23 is composed of an iron metal structure 23a formed integrally with the planetary gear 22 and an elastic body 23b made of rubber or resin that is relatively easily deformed or a composite thereof. ing. The structure 23a is formed on both side surfaces of the planetary gear 22 so as to have a smaller diameter than the outer diameter of the planetary gear 22, and a groove having a substantially semicircular cross section is formed on the entire outer periphery of the structure 23a. The elastic body 23b is a member having a circular cross section, and is fixed to the groove of the structure 23a. The elastic body 23b is in frictional contact with the tapered surfaces formed on the inner peripheral surfaces of the fixed ring 21a and the movable ring 21b.
[0031]
Here, as the structure 23a, it is also possible to form it with resin other than metal. In this case, Young's modulus is 1 × 10²It is desirable to be formed of a resin exceeding MPa, and Young's modulus is 1 × 10^ThreeIf it is more than MPa, it is more preferable. The elastic body 23b has a Young's modulus of 1 × 10.²What is necessary is just below MPa, and 10 MPa or less is more preferable. The Young's modulus of the elastic body 23b is preferably 0.1 MPa or more from the viewpoint of durability. Furthermore, the friction coefficient of the elastic body 23b against the mating member is preferably 0.1 or more, and more preferably 0.3 or more.
[0032]
A compression coil spring 30 is disposed on the side of the movable ring 21b, and the movable ring 21b is always urged toward the fixed ring 21a by the compression coil spring 30. As a result, a predetermined pressing force is applied to the contact surfaces of the elastic body 23b of each planetary roller 23 and the fixed ring 21a and the movable ring 21b, and each elastic body 23b is elastically deformed and pressed against the mating member. . Note that the compression coil spring 30 can be omitted by forming the elastic body 23b attached to the planetary roller 23 with rubber or the like which is more easily elastically deformed.
[0033]
The carrier 24 is a ring-shaped member, and an output shaft 25 is inserted into a hole in the center portion and fixed so as not to rotate relative to each other. The carrier 24 and the output shaft 25 can be formed integrally.
The speed detection mechanism 3 includes a pulse disc 35 fixed to the side surface of the carrier 24 and a photodetector 36 including a projector and a light receiver. With such a configuration, the rotation speed of the carrier 24, that is, the output shaft is detected, and the detection result is sent to the controller 4.
[0034]
The controller 4 is a control circuit that can output a motor drive signal composed of a CPU or the like, and outputs a motor drive signal based on the detection output from the light detection unit 36 so that the output rotation speed becomes a desired set value. Circuit. The driver device 5 is a device for driving the motor 1 based on a motor drive signal from the controller 4.
[0035]
Next, the operation will be described.
When the rotating shaft 14 rotates by driving the motor 1, this rotation is input to the reduction gear 2. This rotation is decelerated by a reduction ratio determined by the number of teeth of the sun gear 20 and the planetary gear 22 and the outer diameter and inner diameter of the planetary roller 23 and the internal ring 21, and is output via the carrier 24 and the output shaft 25.
[0036]
At this time, the rotational speed of the carrier 24 is detected as a pulse signal by the pulse plate 35 and the photodetector 36 fixed to the side surface of the carrier 24, and this pulse signal is input to the controller 4. In the controller 4, the phase difference between the rotation speed detection pulse obtained by the photodetector 36 and the reference pulse is detected, and a motor drive signal that eliminates this phase difference is input to the drive device 5. Then, the rotational speed of the motor 1 is increased or decreased by a drive signal from the drive device 5.
[0037]
By such feedback control, the rotational speed of the motor 1 is controlled so that the output rotational speed of the reduction gear 2 becomes a desired set speed.
In this device, since the sun gear 20 and the planetary gear 22 transmit torque by meshing the gears, there is no slip between them, and transmission efficiency is improved compared to frictional contact. Further, the speed fluctuation occurs due to the transmission by the meshing of the gears, but the speed fluctuation can be absorbed by the frictional contact between the planetary roller 23 and the internal ring 21 provided on the output side.
[0038]
Further, since the planetary roller 23 is composed of the metal structure 23a other than the frictional contact portion and the rubber or resin elastic body 23b of the frictional contact portion, the gear portion seems to be impregnated with the lubricant. By using a simple resin, the traction oil required in the conventional apparatus is not required. And since traction oil becomes unnecessary, the highly accurate process of the sealing surface of the other member which a sealing member and the sealing member slidably contact becomes unnecessary. Further, since the assembly error, the processing error, and the like can be absorbed by the elastic deformation of the elastic body 23b, the processing accuracy of each part can be lowered as compared with the conventional case. Furthermore, the friction coefficient of the friction contact portion can be increased while ensuring the strength by the structure 23b, and efficient torque transmission can be performed.
[0039]
[Modification of First Embodiment]
Below, the modification of 1st Embodiment is shown.
(1) FIG. 3 shows another example of a planetary gear and a planetary roller.
The planetary gear 40 is a spur gear that can mesh with the sun gear 20 as described above. The planetary roller 41 is composed of a structure 41a formed integrally with the planetary gear 40 and an elastic body 41b. The structure 41a is formed on the side surface of the planetary gear 40, and the outer peripheral surface thereof is formed in a tapered shape having a smaller diameter as it goes outward. The material of each member is the same as in the above example. However, in this example, the elastic body 41b is provided on the entire outer peripheral surface of the structure 41a by adhesion or coating.
[0040]
(2) In the example shown in FIG. 4, the planetary gear 45 and the planetary roller 46 are integrally formed. The planetary gear 45 is a spur gear that can mesh with the sun gear 20 as described above. Further, the planetary roller 46 is formed on both side surfaces of the planetary gear 45, and the outer peripheral surface thereof is formed in a tapered shape having a smaller diameter as it goes outward as described above.
On the other hand, the internal ring 47 has an annular fixed ring 471 and a movable ring 472, and both the rings 471 and 472 are provided to face each other so as to sandwich the planetary gear 45 and the planetary roller 46. Both rings 471 and 472 are composed of structures 471a and 472a and elastic bodies 471b and 472b. The material of both members is the same as in the above example. In the structures 471a and 472a, the opposing surfaces of the inner peripheral portion are formed in a tapered shape, and are opposed to the tapered outer peripheral surface of the planetary roller 46. The elastic bodies 471b and 472b are provided on the inner peripheral tapered surfaces of the structures 471a and 472a by adhesion or coating, and are in frictional contact with the planetary roller 46, respectively.
[0041]
(3) In the example shown in FIG. 5, the pair of rings 50 and 51 constituting the internal ring are made of an elastic body. That is, the internal ring in this example is entirely composed of an elastic body and does not have a structure. Other configurations are the same as the example shown in FIG.
In this case, since a large amount of elastic deformation can be secured in the internal ring, a member (compression coil spring) for biasing the ring can be eliminated.
[0042]
(4) The example shown in FIG. 6 has the same basic configuration as the examples shown in FIGS. Here, the shapes of the planetary roller 56 and the internal ring 57 are different.
That is, the planetary roller 56 is formed in a cylindrical shape on both side surfaces of the planetary gear 45 and is composed of only a structure. The internal ring 57 includes a structure 57a in which a pair of rings are integrally formed, and an elastic body 57b. The elastic body 57b is provided on the inner peripheral end surfaces of a pair of integrally formed rings by adhesion or coating. The material of each member is the same as in the above example.
[0043]
[Second Embodiment]
FIG. 7 shows a second embodiment of the present invention. This embodiment is different from the first embodiment only in the speed reduction device portion, and the other configuration is the same as that of the first embodiment.
The speed reducer 60 includes a sun roller 61, a planetary roller 62 and a planetary gear 63, an internal gear 64, and a carrier 65 that supports the planetary roller 62 and the planetary gear 63.
[0044]
The sun roller 61 is formed at the tip of the motor rotating shaft 14. The planetary roller 62 and the planetary gear 63 are integrally formed of metal or resin except for an elastic body 62b described later, and are cantilevered by a carrier 65 by a rod 66 that passes through a hole formed in the center. The planetary roller 62 includes a structure body 62a and an elastic body 62b. The structure 62a has a groove having a substantially semicircular cross section on the entire outer periphery. The elastic body 61 b is fixed in the groove 62 a by fitting or the like, and the elastic body 61 b is in frictional contact with the outer periphery of the sun roller 61. The material, Young's modulus, and friction coefficient of each member are the same as in the above example. The planetary gear 63 is a spur gear having teeth on the outer periphery, is formed on the side of the planetary roller 62, and has a smaller diameter than the outer diameter of the planetary roller 62. The internal gear 64 is formed in a ring shape and is fixed to the housing by a pin 67. Further, teeth that mesh with the planetary gear 63 are formed on the inner peripheral surface of the internal gear 64.
[0045]
The operation of this embodiment is the same as that described above, but here, there is meshing with the gear on the output side of the friction contact portion. Therefore, the speed variation due to the meshing of the gears cannot be absorbed by the elastic body. However, in this apparatus, since there is a meshing portion with the gear after being decelerated, the frequency of the speed fluctuation caused by the meshing (hereinafter referred to as the meshing frequency) becomes relatively low. On the other hand, the frequency response of the motor has good responsiveness when the frequency is low, so that it becomes easy to cancel the speed fluctuation caused by the meshing by canceling the feedback.
[0046]
As a control method for canceling the speed fluctuation, there are the following methods.
<General feedback control>
If the frequency response of the motor is higher than the meshing frequency, the meshing variation can be reduced by feedback control.
<Learning control>
Since the meshing in this device depends on the tooth profile of the internal gear, the rotation result is temporarily sampled, and the rotation control of the motor is performed so as to cancel the fluctuation in synchronization with the cycle to be canceled in the output shaft. .
[0047]
<Learning control + feedback>
The rotation control is performed by continuously using the learning control together with the feedback control. In other words, while performing feedback control, the rotation results are always sampled for periodic fluctuations that cannot be removed by feedback control, and the fluctuations of the motor are canceled in synchronization with the period to be canceled in the output shaft. Generate a rotation command.
[0048]
[Modification of Second Embodiment]
Below, the modification of 2nd Embodiment is shown.
(1) The planetary roller 62 'shown in FIG. 8 is composed of a structural body 62a' and an elastic body 62b '. The material of each member is the same as the above example. However, in this example, the elastic body 62a 'is provided on the entire outer peripheral surface of the structure 62a' by adhesion or coating.
[0049]
(2) The speed reducer 70 shown in FIG. 9 includes a sun roller 71, a planetary roller 72 and a planetary gear 63, an internal gear 64, and a carrier 65 that supports the planetary roller 72 and the planetary gear 63.
This device differs from the above example only in the sun roller 71 and the planetary roller 72, and the other configurations are the same. That is, the sun roller 71 is composed of a structure 71a formed at the tip of the motor rotating shaft 14 and an elastic body 71b provided on the outer periphery of the structure 71a. The elastic body 71b is provided on the outer periphery of the structure 71a by adhesion, coating or fitting. The material, Young's modulus, and friction coefficient of each member are the same as in the above example.
[0050]
The planetary roller 72 is a disk-shaped member, and the outer periphery thereof is in frictional contact with the elastic body 71 b of the sun roller 71.
[Third Embodiment]
FIG. 10 shows a third embodiment of the present invention.
This device is a two-stage parent-child inscribed type reduction device that detects the output rotational speed of the motor 1, the reduction device 82 including the first reduction portion 80 and the second reduction portion 81, and the reduction device 82. A speed detection mechanism 3, a controller 4, and a drive device 5. The configurations of the motor 1, the speed detection mechanism 3, the controller 4, and the drive device 5 are the same as those in the first embodiment.
[0051]
The first reduction gear 80 has a sun gear 85 and an internal gear 86 that are integrally formed at the tip of the motor rotating shaft 14. The internal gear 86 has a gear portion 87 that meshes with the sun gear 85 and an intermediate output shaft 88 provided at the center of the gear portion 87. The intermediate output shaft 88 is rotatably supported on the wall 89 of the housing via a bearing.
[0052]
The second speed reducing portion 81 has a friction wheel 91 integrally formed with the output shaft 90, and the output shaft 90 is rotatably supported by the end cover of the housing via two bearings. The friction wheel 91 has a structure 92 made of metal or resin, and an elastic body 93 made of rubber or resin or a composite of these fixed to the inner periphery of the structure 92. The structure 92 is a disk-shaped member, and includes a disk portion 92a and a cylindrical portion 92b formed to extend in parallel with the output shaft 90 from the outer peripheral portion of the disk portion 92a. The elastic body 93 is fixed to the entire inner peripheral surface of the cylindrical portion 92b.
[0053]
The material, Young's modulus, and friction coefficient of the structure 92 and the elastic body 93 in the friction wheel 91 are the same as those in the above embodiment.
In the rotary drive device having such a configuration, the rotation of the motor 1 is output to the intermediate output shaft 88 after being decelerated by the first reduction unit 80, and further to the output shaft 90 after being decelerated by the second reduction unit 81. Is done. The rotation speed of the output shaft 90 is detected by the speed detection mechanism 3, and the rotation speed is feedback-controlled by the controller 4 and the drive device 5 as in the above embodiment. Therefore, the rotational speed of the output shaft 90 can be controlled to a desired rotational speed with high accuracy.
[0054]
Here, since the rotation of the first reduction gear 80 is transmitted by the meshing of the gears, good transmission efficiency can be obtained. Further, although the speed variation occurs due to the meshing of the gears, this speed variation is absorbed by the frictional contact by the elastic body of the second reduction part 81, and a smooth rotational output is obtained.
[Fourth Embodiment]
FIG. 11 shows a fourth embodiment of the present invention.
[0055]
In the apparatus of this embodiment, the configurations of the rotation transmission units of the first reduction unit and the second reduction unit in the third embodiment are reversed. That is, the first speed reduction unit 100 performs rotation transmission by frictional contact, and the second speed reduction unit 101 performs rotation transmission by meshing of gears. Other configurations are the same as those of the above embodiment.
First, the first reduction gear unit 100 includes a friction wheel 106 having an intermediate output shaft 105. As described above, the friction wheel 106 includes a disk 110 and a structure 110 having a cylindrical portion formed in parallel with the output shaft 107 from the outer periphery of the disk portion, and an inner peripheral surface of the cylinder of the structure 110. And an elastic body 111 fixed to the entire circumference.
[0056]
In addition, the second reduction gear unit 101 includes a small gear 115 fixed to the intermediate output shaft 105 of the friction wheel 106 by a key, and an internal gear 116 that is integrally formed with the output shaft 107 and meshes with the small gear 115.
The operation is basically the same as in the third embodiment, but in this case, as in the second embodiment, since there is meshing with the gear on the output side of the friction contact portion, the speed fluctuation caused by the meshing is reduced. The frequency becomes relatively low, and the speed fluctuation due to the meshing is easily canceled by feedback control.
[0057]
[Fifth Embodiment]
FIG. 12 shows a fifth embodiment of the present invention. This embodiment is different from the third embodiment only in the first reduction part, and the other configuration is the same.
That is, the first reduction gear 120 in this apparatus has a sun gear 85 formed at the tip of the rotating shaft 14 and a reduction gear 121 having teeth that mesh with the sun gear 85 on the outer periphery. The reduction gear 121 is fixed to an intermediate output shaft 124 supported by two bearings 122 and 123.
[0058]
According to this embodiment, the same effect as that of the third embodiment can be obtained.
[Sixth Embodiment]
FIG. 13 shows a sixth embodiment of the present invention.
In the apparatus of this embodiment, the configurations of the rotation transmission units of the first reduction unit and the second reduction unit in the fifth embodiment are reversed. That is, the first speed reduction unit 130 performs rotation transmission by frictional contact, and the second speed reduction unit 131 performs rotation transmission by gear meshing. Other configurations are the same as those of the above embodiment.
[0059]
The first reduction gear unit 130 includes a friction wheel 132, and the friction wheel 132 is fixed to an intermediate output shaft 133 supported by two bearings 122 and 123. The friction wheel 132 has a structure 134 and an elastic body 135 provided on the entire outer peripheral surface of the structure 134. The elastic body 135 is in frictional contact with the tip of the rotating shaft 14.
[0060]
The second reduction gear 131 includes a small gear 140 formed integrally with the end of the intermediate output shaft 133 and an internal gear 141 similar to the internal gear 116 shown in FIG. That is, the internal gear 141 is integrally formed with the output shaft 142 and meshes with the small gear 140.
The operation is basically the same as in the fifth embodiment, but in this case, as in the second and fourth embodiments, there is meshing with the gear on the output side of the frictional contact portion, so that it is caused by meshing. The frequency of the speed fluctuation becomes relatively low, and the speed fluctuation due to the meshing is easily canceled by feedback control.
[0061]
[Other Embodiments]
(1) In each of the above embodiments, the planetary roller and the planetary gear are integrally formed, but they may be formed separately.
(2) In the case of using a planetary speed reduction mechanism, the differential planetary mechanism in which the diameters of the planetary roller and the planetary gear are different is taken as an example in the above embodiment, but the present invention is also applied to a simple planetary mechanism having the same diameter. Can be applied as well.
[0062]
(3) The configuration of the speed reducer is not limited to the examples of the above embodiments. For example, as schematically shown in FIG. 14, the first transmission mechanism 152 that decelerates the rotation of the motor 1 by the meshing of a pair of gears 150 and 151, and the planetary system to which the output of the first transmission mechanism 152 is input. The second transmission mechanism 153 may be disposed, and a rotating member with an elastic body may be used for at least one of the sun wheel 154, the planetary wheel 155, and the internal ring 156 constituting the second transmission mechanism 153. Conversely, the first transmission mechanism 152 may be a friction transmission using a rotating member with an elastic body, and the second transmission mechanism 153 may be a rotation transmission by meshing of gears.
[0063]
Further, as schematically shown in FIG. 15, the planetary first transmission mechanism 160 to which the rotation of the motor 1 is input, and the output of the first transmission mechanism 160 is input to engage the pair of gears 161 and 162. The second transmission mechanism 163 that decelerates may be disposed, and a rotating member with an elastic body may be used for at least one of the sun wheel 164, the planetary wheel 165, and the internal ring 166 constituting the first transmission mechanism 160. Conversely, the second transmission mechanism 163 may be a friction transmission using a rotating member with an elastic body, and the first transmission mechanism 160 may be a rotation transmission by meshing of gears.
[0064]
【The invention's effect】
As described above, according to the present invention, the friction wheel in the traction type reduction gear is composed of the structural body and the elastic body having an appropriate Young's modulus, so that it is not necessary to lubricate the friction contact portion. In addition, since the portion other than the frictional contact portion of the friction wheel is formed of a structure, the strength of the structure is not increased and the strength is not insufficient. Furthermore, since assembly errors and processing errors can be absorbed by elastic deformation of the elastic body, options for processing accuracy, processing method, and material of the friction wheel are widened, and manufacturing costs can be reduced.
[0065]
Further, when a part of the transmission portion is engaged with the gear together with the above-described friction wheel with an elastic body, in addition to the above effects, loss during rotation transmission can be suppressed.
[Brief description of the drawings]
FIG. 1 is a cross-sectional configuration diagram of a rotary drive device according to a first embodiment of the present invention.
FIG. 2 is an enlarged partial view of FIG.
FIG. 3 is a view showing a modification of the first embodiment.
FIG. 4 is a view showing a modification of the first embodiment.
FIG. 5 is a view showing a modification of the first embodiment.
FIG. 6 is a view showing a modification of the first embodiment.
FIG. 7 is a view showing a modification of the first embodiment.
FIG. 8 is a view showing a modification of the second embodiment.
FIG. 9 is a view showing a modification of the second embodiment.
FIG. 10 is a cross-sectional configuration diagram of a rotary drive device according to a third embodiment of the present invention.
FIG. 11 is a cross-sectional configuration diagram of a rotary drive device according to a fourth embodiment of the present invention.
FIG. 12 is a cross-sectional configuration diagram of a rotary drive device according to a fifth embodiment of the present invention.
FIG. 13 is a cross-sectional configuration diagram of a rotary drive device according to a sixth embodiment of the present invention.
FIG. 14 is a schematic view of a rotary drive device according to still another embodiment of the present invention.
FIG. 15 is a schematic view of a rotary drive device according to still another embodiment of the present invention.
[Explanation of symbols]
1 --- Motor
2 --- Decelerator
4 --- Controller
5 --- Drive device
20 --- Sun gear
21,47 --- Internal ring
22, 40, 45, 63 --- planetary gear
23, 41, 46, 56, 62, 72 --- Planet roller
23a, 41a, 471a, 57a, 62a, 71a, 92a, 110 --- structure
23b, 41b, 471b, 50, 51, 57b, 62b, 71b, 92b, 111 --- elastic body
24,65 --- Carrier
25, 90, 107, 142-Output shaft
61, 71 --- Sun Roller
64,86,116,141 --- internal gear
92,116 --- friction wheel
88,105,124 --- Intermediate output shaft

Claims (5)

A rotational driving device for rotationally driving the driven device and detecting the output rotational speed to feedback control the driving rotational speed,
A motor as a rotational drive source;
A speed reducer that receives the rotation of the motor and has a friction transmission portion that transmits torque by frictional contact of one or more rotating members, and decelerates and outputs the rotation from the motor;
A speed detection mechanism for detecting the output rotation speed of the reduction gear,
At least one member among the members that transmit torque by the friction transmission includes a rubber-equipped member having a structure that forms a portion other than the friction contact portion and rubber that forms the friction contact portion.
The rubber of the rubber-attached member is provided so that the member having the rubber-attached member and the other member in contact with the rubber are elastically deformed without moving and are in pressure contact with the other member in contact with the rubber. A rotation drive device, which is characterized.   The rotary drive device according to claim 1, wherein the structure has an annular groove around the entire outer periphery, and the rubber is mounted in the groove.   The rotation drive device according to claim 1, wherein the rubber is provided integrally with the structure on an outer peripheral surface of the structure.   The rotation drive device according to any one of claims 1 to 3, wherein the structure is a resin molded product. The speed reducer has at least two rotation transmission parts, and the at least two rotation transmission parts include a rotation transmission part by frictional contact of the rubber-equipped member and a rotation transmission part by meshing of gears,
The rotation transmission part by meshing of the gear is
A sun gear provided at the tip of the rotating shaft of the motor and having teeth formed on the outer periphery;
A plurality of planetary gears formed on the outer periphery with teeth meshing with the sun gear,
The rotation transmission part by frictional contact of the rubber member is
An internal ring arranged concentrically with the sun gear;
A plurality of planetary rollers that are in frictional contact with the internal ring and are non-rotatable relative to the planetary gear;
The rotation drive device according to any one of claims 1 to 4, wherein at least one of the planetary roller and the internal ring is the rubber member.

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