JP2007278431A - Reduction gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a double-shaft output reduction gear 10a forming an output shaft of the reduction gear to carry out double-shaft output. <P>SOLUTION: The reduction gear comprises an eccentric shaft 20 converting rotary motion into eccentric rotary motion and inserting the output shaft 13 through; a first gear 22 put in eccentric swinging motion by the eccentric shaft 20; a second gear 24 partially meshed with the first gear following the eccentric motion of the first gear 22 and connected to the output shaft 13; a regulating pin 23 for rotating the second gear 24 by regulating rotating motion generated to the first gear 22 when the second gear 24 and the first gear 22 are partially meshed; and a pulley 14 transmitting rotating power of a motor 13 disposed non-coaxially with the output shaft 13, to the eccentric shaft 20 and taking out output from both ends of the output shaft 13 to form a double-shaft output shaft with the output shaft 13 projected out of the right and left of the reduction gear. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a speed reducer that decelerates and outputs rotational power with high power transmission efficiency and a high reduction ratio.

  Various products such as electrical appliances and industrial products in recent years need a governor as a speed governor for the purpose of adjusting the number of rotations of the motor that is the driving source and the number of rotations required by the driven source. Reduction gears are used in many fields as a torque amplifying device for obtaining a large torque.

  Such a reduction gear is desired to be small and have a large reduction ratio with a simple configuration and to have high power transmission efficiency. However, conventionally, a plurality of spur gears 101 as shown in FIG. 9 are combined to adjust the rotational speed of the motor 100 and output it to the output shaft 102. For this reason, the size of the speed reducer is increased, and it is difficult to secure a storage space in a device that has a large demand for downsizing.

  It should be noted that with a speed reducer comprising a combination of an existing worm and worm wheel, a large reduction ratio can be easily obtained. However, since the speed reducer transmits power by sliding the meshed teeth, There is a problem of large power loss due to wear and sliding.

On the other hand, a planetary reduction gear using a planetary gear has a feature that a large reduction ratio can be easily obtained while having a simple configuration, and power loss can be reduced because sliding of a meshing portion can be suppressed. I have.
As an apparatus using such a planetary speed reducer, Patent Document 1 proposes an automatic opening / closing device that decelerates the rotational power of a motor by a planetary speed reducer and rotates a hinge shaft of an opening / closing member.

  However, since the conventional planetary speed reducer has a configuration in which the motor shaft and the input shaft of the speed reducer are provided coaxially, there is a problem that the output shaft of the speed reducer cannot act as a hinge shaft. In other words, since the output of the speed reducer is a single shaft, there is a disadvantage that it cannot be used as a hinge shaft having both ends as action points.

  Moreover, even if it is desired to drive both the left and right wheels simultaneously, such as an electric wheelchair for care, for example, it is not possible to directly drive the left and right wheels whose output shaft of the speed reducer is one axis.

In the image forming apparatus, a lift is provided for moving the recording paper placed on the tray up and down in accordance with the consumption of the recording paper. In this lift as well, the output shaft of the reduction gear and the driven shaft are provided. And cannot be provided coaxially.
JP 2005-325523 A

As described above, the conventional planetary speed reducer can meet the demand for power saving and downsizing, but there is a problem that the downsizing cannot be sufficiently achieved because the output shaft is a single-axis output.
Accordingly, an object of the present invention is to provide a speed reducer that can output both axes with a simple configuration.

Further, since the speed reducer having the above configuration is configured such that the motor and the speed reducer are coaxially arranged in the axial direction of the output shaft, it may be difficult to secure an installation space in the axial direction.
Accordingly, an object of the present invention is to provide a reduction gear that is thin so that it can be easily installed even when an installation space cannot be secured in the axial direction.

In addition, since the motor and the speed reducer are basically separate structures, there is a problem that the space occupied by them increases.
Therefore, the present invention is characterized in that the motor and the speed reducer are integrally configured so that they can be installed in a small space.

Further, since the reduction ratio depends on the number of teeth of the planetary gear, there is a problem that the reduction ratio cannot be made extremely large. That is, if it is intended to achieve a reduction gear with a reduction ratio of 300 or more, the number of teeth of the planetary gear must be set to 300 or more. It becomes a factor that prevents
Therefore, an object of the present invention is to enable multistage deceleration so that a large reduction ratio can be easily obtained even with a small size.

Furthermore, in order not to apply a torque exceeding a certain value to the output shaft, it is necessary to additionally install a torque limiter, which causes a problem of increasing the size.
Therefore, an object of the present invention is to provide a speed reducer with a built-in torque limiter.

  In order to solve the above problems, an eccentric shaft that converts rotational motion into eccentric rotational motion and through which an output shaft is inserted, a first gear that performs eccentric motion by the eccentric shaft, and an output shaft are inserted and connected. The second gear partially engaging with the first gear with the eccentric motion of the first gear, and the second gear by regulating the rotational motion of the first gear while allowing the eccentric rocking motion of the first gear. And a regulation pin for rotating the gear.

  An eccentric shaft that converts the rotational motion into an eccentric rotational motion and through which the output shaft is inserted, a first gear that moves eccentrically by the eccentric shaft, and an eccentric motion of the first gear that is fixedly provided. Accordingly, the second gear partially meshed with the first gear, the output shaft is inserted and connected, and the output extraction member that rotates by the rotation of the first gear, the first gear and the output extraction member are passed. And at least one of which is swingably mounted and includes a regulation pin that transmits the rotation of the first gear to the output extraction member.

  Also, an eccentric shaft that converts rotational motion into eccentric rotational motion, a first gear that has an inner tooth and is driven by the eccentric shaft, and an eccentric motion. A second gear partially meshed with the first gear in accordance with the core movement, and a regulation pin for regulating the rotation of the first gear and allowing the second gear to rotate while allowing the eccentric rocking movement of the first gear. It is characterized by having.

  Also, an eccentric shaft having an eccentric portion that converts rotational motion into eccentric rotational motion, a first gear that performs eccentric oscillating motion by the eccentric shaft, and associated with the eccentric motion of the first gear There are provided a plurality of speed reducers each including a second gear partially meshed with the first gear, and the second gear in the front stage reduction gear also serves as an eccentric part in the rear speed reducer, and all A restriction pin for restricting rotation of the first gear in the speed reducer is loosely fitted into each first gear and is inserted.

  Further, the rotational motion transmitted to the eccentric shaft is the rotational motion of the motor, and the rotor of the motor is provided integrally with the eccentric shaft, or the eccentric shaft is formed on the rotor. It is characterized by.

  Also, an eccentric shaft that converts rotational motion into eccentric rotational motion, a first gear that performs eccentric swing motion by the eccentric shaft, and the first gear and partial teeth that accompany the eccentric motion of the first gear A second gear to be coupled, a regulation pin for regulating the rotation of the first gear while allowing the eccentric rocking motion of the first gear to rotate the second gear, and an output shaft mounted on the eccentric shaft. And a torque limiter that prevents the rotational power from the motor from being transmitted to the eccentric shaft by slipping when the driving torque exceeds a predetermined value.

  Further, an eccentric shaft that converts rotational motion into eccentric rotational motion, a first gear that is eccentrically oscillated by the eccentric shaft and that is swingable in the axial direction, and the first gear A second gear having a tooth portion facing the tooth portion on a plane perpendicular to the rotation axis and partially meshed with the first gear in accordance with the eccentric motion of the first gear; A regulation pin for regulating the rotation of the first gear while allowing the movement to rotate the second gear, and an eccentric shaft are provided so as to be rotatable integrally with the eccentric shaft, and urge the first gear with a predetermined force. An urging member that partially meshes the first gear and the second gear is provided.

  Further, an eccentric shaft that converts rotational motion into eccentric rotational motion, a first gear that performs eccentric swing motion by the eccentric shaft, and the first gear and partial teeth that accompany the eccentric motion of the first gear A second gear to be engaged, and one of the first gear and the second gear is made of resin and the other is made of metal.

  According to the present invention, the output shaft is inserted through the eccentric shaft, and the rotational power of the motor is transmitted to the eccentric shaft via a pulley or the like, so that it is possible to output both shafts with a small and simple configuration. become.

  In addition, since the eccentric shaft is inscribed in the first gear, the second gear is internally engaged with the first gear, and the output shaft is inserted through the second gear. Can be small.

  In addition, the first gear is inscribed in the eccentric shaft, the second gear is internally engaged with the first gear, and the output shaft is inserted through the second gear. Can be small.

  Moreover, since the eccentric shaft is formed integrally with the rotor of the motor, a small reduction gear with a built-in motor can be manufactured.

  Further, the speed reducer is constituted by a speed reducer composed of a plurality of first gears and second gears, etc., and the second gear in the front stage side reducer also serves as an eccentric part in the rear stage side speed reducer, and all the speed reducers Since the restriction pin for restricting the rotation of the first gear in the machine is loosely fitted to each first gear and inserted therethrough, a reduction gear with a high reduction ratio can be easily and compactly formed while reducing the number of parts. Is possible.

  Further, since the torque limiter is provided on the input side, the output side torque control can be performed with a small torque value.

  Also, a biasing member for biasing the first gear is provided, with the tooth portions of the first gear and the second gear facing each other in a plane perpendicular to the rotation shaft, and the first gear being provided so as to be able to swing in the axial direction. Since it is provided, there is no restriction on the difference in the number of teeth of the first gear and the second gear, and it can be formed so that the deceleration function, the speed increasing function, and the joint function can be expressed, and the urging member according to the elastic force It becomes possible to act as a torque limiter.

  Since at least one of the first gear and the second gear is made of resin, tooth wear can be suppressed.

  A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a double shaft output speed reducer according to the present invention.

  The speed reducer 10 a includes a pulley 14 to which rotational power from a motor 11 such as a servomotor is transmitted, an eccentric shaft 20 that is connected to the pulley 14 and rotates coaxially, and an eccentricity that accompanies the rotation of the eccentric shaft 20. A first gear 22 that receives motion through a bearing 25b, a regulation pin 23 that regulates the rotation of the first gear 22, a second gear 24 that partially rotates with the first gear 22, and a rotation of the second gear 24. And an output shaft 13 to which rotational power is transmitted. The output shaft 13 is housed in a casing 28, and the output shaft 13 is inserted into the eccentric shaft 20 to be a biaxial output.

  The second gear 24 is supported by a bearing 35a, the eccentric shaft 20 is supported by bearings 25c and 25d, and the output shaft 13 is supported by a bearing 25e.

Then, the rotation of the motor 11 is transmitted to the pulley 14 via the timing belt 12. Since the eccentric shaft 20 including the eccentric portion 21 is fixed to the pulley 14, the eccentric motion of the eccentric portion 21 is transmitted to the first gear 22 via the bearing 25b.
Accordingly, the first gear 22 follows the eccentric movement of the eccentric portion 21 and performs an eccentric movement. At this time, the eccentric movement direction rotates, so that the first gear 22 also rotates (spins).

  However, since the regulation pin 23 is fixed to the first gear 22 and the head of the regulation pin 23 is accommodated in the pin loose hole 26 formed in the casing 28, the first gear 22 rotates. Only the eccentric rocking motion is allowed.

  When the first gear 22 performs eccentric movement, the first gear 22 and the second gear 24 are partially engaged in this eccentric direction, and the teeth of the other portions are separated from each other. The part rotates according to the eccentric direction, and this rotation is transmitted as the rotation of the second gear 24.

  The teeth of the first gear 22 and the second gear 24 are formed by a cyclod curve, and each tooth rolls without sliding to change the meshing state. That is, the power transmission efficiency can be remarkably improved to 90%, for example, compared to the case of a spur gear with sliding (for example, 30%).

  The rotation speed of the second gear 24 depends on the difference in the number of teeth between the first gear 22 and the second gear 24, and the number of teeth of the second gear 24 is smaller than the number of teeth of the first gear 22, so the motor rotation speed is reduced. Then, it is transmitted to the output shaft 13. If the number of teeth of the first gear 22 is N1 and the number of teeth of the second gear 24 is N2, the reduction ratio γ is given by γ = (N1−N2) / N2.

  In the above description, the case of using a pulley has been described. However, the rotational power of the motor 11 may be transmitted to the eccentric shaft 20 by a general gear such as a spur gear.

  In the above description, the rotation of the first gear 22 is restricted by the restriction pin 23 and the second gear 24 is fixed to the output shaft 13. However, the output shaft 13 is provided with an output extraction plate (not shown). The same effect can be obtained by loosely fixing or fixing the restriction pin 23 to the output extraction plate to fix the second gear 24 immovably. The same applies to the following embodiments.

  With such a configuration, the reduction gear can easily and easily output both shafts with a high reduction ratio with a small number of parts, and the space volume occupied by the conventional reduction gear can be reduced.

  Further, the eccentric shaft 20 is inscribed in the first gear 22, the second gear 24 is internally engaged with the first gear 22, and the output shaft 13 is inserted through the second gear 24. Thus, the power transmission direction is folded back at the meshing position between the second gear 24 and the second gear 24, and the radial dimension of the output shaft 13 can be reduced.

  The present invention does not particularly limit the application target of such a double-axis output speed reducer, but as an example, a case where the present invention is applied to a lift mechanism that moves a recording sheet up and down in an image forming apparatus will be described with reference to FIG. explain.

The reduction gear 10 a is attached to a reduction gear mounting plate 53 erected on the bottom plate 54 b of the lift frame 54.
Two arm shafts 56a and 56b are provided across the side plate of the lift frame 54, and one arm shaft 56a serves as the output shaft 13 of the speed reducer 10a.
Lift arms 52 a and 52 b are fixed to the arm shafts 56 a and 56 b, and the lift arms 52 a and 52 b are connected by a connecting bar 51.

When the speed reducer 10a operates, the output rotates the arm shaft 56a. Since the lift arm 52a and the lift arm 52b are connected by the connecting bar 51, when the arm shaft 56a is rotated, the lift arm 52b is similarly rotated.
As a result, the rollers 55 attached to the tips of the lift arms 52a and 52b change the height in synchronization, and the height of the tray (not shown) on which the recording paper is placed can be adjusted.

  By using the speed reducer for such a lift, the left and right lift arms 52a and 52b can be easily rotated while being small in size.

  In particular, most of the space for storing the reduction gear (the space formed by the side plate 54a and the bottom plate 54b) is a dead space. In order to reduce the dead space, it is necessary to reduce the side plate height dimension h of the reduction gear. There is.

  In the above configuration, since the power transmission direction is folded back at the meshing position between the first gear 22 and the second gear 24, the side plate height dimension h can be reduced, and the generation of a large dead space is suppressed. There is an advantage that makes it possible.

  In addition, since the reduction ratio in the reduction gear depends on the difference in the number of teeth between the first gear 22 and the second gear 24, for example, the number of teeth between the first gear 22 and the second gear 24 is 49 and 50, respectively. A reduction ratio of 1/50 can be obtained, and a large load can be moved up and down even with the motor 11 having a small torque. Accordingly, there is an advantage that the motor 11 can be easily downsized and the design conditions such as cooling of the motor are relaxed.

  In addition, since this reduction gear has a large reduction ratio, there is an advantage that it is possible to prevent reverse rotation of the reduction gear even if the braking force on the motor side is small.

  Next, a second embodiment of the present invention will be described with reference to FIG. A reduction gear 10b shown in FIG. 3 includes a power transmission gear 31 that transmits the rotational power of the motor 11, an eccentric gear 33 that is supported by a bearing 39c and rotates by the rotational power from the power transmission gear 31, and the eccentric gear 33. The first gear 35 that meshes, the regulation pin 34 that is loosely fitted in the plurality of pin loose holes 38 formed in the first gear 35, and the end portion is fitted to the casing 30, and the first gear 35. And a second gear 36 connected to the output shaft 37.

  The power transmission gear 31 is attached to the motor shaft 32 by a spur gear, for example. The eccentric gear (eccentric shaft) 33 is rotatably supported by a bearing 39c, and is an eccentric portion formed by opening an inner peripheral portion thereof.

  Inner teeth are formed inside the first gear 35, and a plurality of pin loose holes 38 are formed at equal intervals in the circumferential direction in the thickness direction, and the eccentric movement from the eccentric gear 33 via the bearing 39d. Is transmitted. At this time, the rotation movement is restricted by the restriction pin 34 loosely fitted in the pin loose fitting hole 38, and only the eccentric rocking movement is allowed.

  The second gear 36 is fixed to the output shaft 37, and external teeth are formed on the outer peripheral surface thereof. Then, the first gear 35 that has made an eccentric motion rotates in a partially meshed manner with the first gear 35, and the rotation motion is transmitted to the output shaft 37.

  In the above description, gears such as spur gears are used, but belt transmission using pulleys may be used.

  With such a configuration, the reduction gear can easily and easily output both shafts with a high reduction ratio with a small number of parts, and the space volume occupied by the conventional reduction gear can be reduced.

  In addition, since all the components have an inclusion relationship, there is an advantage that the thickness of the speed reducer can be reduced, and since the first gear 35 is provided in the eccentric gear 33, the eccentric motion is performed. Transmission to the first gear 35 can be facilitated.

  Further, since the eccentric gear 33 has the function of the eccentric portion, there is an advantage that the number of parts can be reduced.

  In addition, since the eccentric gear 33, the first gear 35, and the second gear 36 sequentially satisfy the inclusion relationship, there is an advantage that the axial dimension of the output shaft 37 can be reduced.

  Next, a third embodiment of the present invention will be described with reference to FIG. In the above-described embodiment, the motor and the speed reducer are configured separately. However, in the speed reducer according to the present embodiment, an eccentric portion is integrally provided on the rotor of the motor.

  In the speed reducer 10c, a stator 41a is provided in a casing 46 that also serves as a motor case. An output shaft 48 is inserted into the rotor 41b. The rotor coil 41c is provided to face the stator 41a, and a rotor eccentric portion 41d is formed at one end. As a result, when the rotor 41b rotates, the rotor eccentric portion 41d also rotates.

  A first gear 42 is fitted into the rotor eccentric portion 41d through a bearing 47d. Inner teeth are formed on the inner peripheral side of the first gear 42, and a plurality of pin loose holes 43 in which the restriction pins 44 are loosely fitted are formed in the thickness direction of the first gear 42. Is allowed, but the rotation is restricted.

  The second gear 45 is provided so as to be included in the first gear 42, and external teeth having fewer teeth than the first gear 42 are formed on the outer peripheral surface thereof.

  Then, the rotation of the rotor 41b is transmitted to the first gear 42 via the rotor eccentric portion 41d and the bearing 47b, and the first gear 42 performs an eccentric swing motion. The first gear 42 and the second gear 45 are partially meshed according to the eccentric motion of the first gear 42, and the change in the eccentric direction appears as the rotation of the second gear 45. Therefore, the second gear 45 rotates at a reduction ratio corresponding to the difference in the number of teeth from the first gear 42, and the output shaft 48 rotates.

  This makes it possible for the motor-integrated double-shaft output reducer to easily and easily output both shafts with a high reduction ratio with few parts, and to reduce the size of the reducer while suppressing the space occupied by the motor. Can do.

  Next, a fourth embodiment of the present invention will be described with reference to FIG. In the above embodiment, the case where the speed reduction is performed by one speed reducer has been described. However, the present invention is not limited to this and may be a multistage speed reduction. FIG. 5 shows a cross-sectional view of the speed reducer in the case of two-stage speed reduction composed of a front speed reducer and a rear speed reducer as an example of multistage speed reduction.

  The front reduction gear includes a front-stage eccentric shaft 65, a front-stage eccentric portion 66 provided on the front-stage eccentric shaft 65, and a front-stage first gear that receives eccentric rotational power from the front-stage eccentric portion 66 via a bearing 79d. 67, and a front second gear 70 that is rotatably supported by a bearing 79e that partially meshes with the front first gear 67.

  Further, in the rear stage reduction gear, the eccentric rotational movement of the rear stage eccentric part 72 formed in the front stage second gear 70 partially meshes with the rear stage first gear 73 and the rear stage first gear 73 via the bearing 79f and is output. A rear second gear 75 connected to the shaft 76 is provided.

  Further, a plurality of front-stage pin loose holes 68 and rear-stage pin loose holes 74 are formed in the thickness direction of the front-stage first gear 67 and the rear-stage first gear 73, respectively, and restriction pins 69 are formed in these pin loose holes. The both ends are inserted into the casing 77a and the casing 77b.

  The output shaft 76 is pivotally supported by bearings 79b and 79g, and the front eccentric shaft 65 is pivotally supported by bearings 79a and 79c so that rotational power from a motor 61 such as a servomotor is transmitted. Are transmitted to the front eccentric shaft 65 via the pulleys 63 and 64.

  When the front eccentric shaft 65 rotates, the eccentric rotational motion of the front eccentric portion 66 is transmitted to the first first gear 67 via the bearing 79d. Since the rotation speed of the first-stage first gear 67 is restricted by the restriction pin, the first-stage first gear 67 moves eccentrically, and partially meshes with the front-stage second gear tooth portion 71 of the front-stage second gear 70 in the eccentric direction. The front second gear 70 rotates. At this time, the rotational speed of the front second gear 70 is determined by the difference in the number of teeth between the front second gear 70 and the front first gear 67.

  As described above, the front-stage second gear 70 is formed with the rear-stage eccentric portion 72 so as to be connected to the front-stage second gear tooth portion 71. Therefore, when the front-stage second gear 70 rotates, the rotation motion is eccentric. The rotation is transmitted to the rear first gear 73 through the bearing 79f.

  The rear stage first gear 73 is formed with a rear stage pin loose-fitting hole 74, and the regulation pin 69 is loosely fitted in the rear stage pin loose-fitting hole 74. The core swings.

  The rear stage first gear 73 is eccentrically oscillated to partially mesh with the rear stage second gear 75 in the eccentric direction, whereby the rear stage second gear 75 rotates. At this time, the rotational speed of the rear second gear 75 is determined by the difference in the number of teeth between the rear first gear 73 and the rear second gear 75.

  Accordingly, the rotational speed of the pulley 64 is decelerated according to the difference in the number of teeth between the first-stage first gear 67 and the second-stage gear 70, and further according to the difference in the number of teeth between the first-stage gear 73 and the second-stage gear 75. As a result, the product of the reduction ratios of the front-stage reduction gear and the rear-stage reduction gear becomes the reduction ratio of the two-stage reduction gear. For example, when the reduction ratio of the front reduction gear is 30 and the reduction ratio of the rear reduction gear is 20, the reduction ratio of the two-stage reduction gear is 600.

  Thus, the rotational power decelerated by two stages is output via the output shaft 76.

  In the above configuration, the large reduction ratio can be easily and easily configured, and the rear-stage eccentric portion is integrally formed with the front-stage second gear, so that the number of parts can be reduced and the size can be reduced.

  Next, a fifth embodiment of the present invention will be described with reference to FIG. The present embodiment relates to a configuration in which a torque limiter is provided in the speed reducer described so far.

As described above, the present speed reducer can be easily configured while satisfying a high power transmission efficiency with a very large reduction ratio. Therefore, if a torque limiter is provided on the output side, a torque limiter that operates with a large torque is required.
As the torque limiter, for example, as shown in FIG. 7, when the operation plates 79a and 79b formed with a plurality of mountain-shaped projections 78 are urged by the torque value setting spring 81, a mountain shape is generated when the limiter is operated with a large torque. Wear on the top of the protrusion 78 increases. Therefore, a material having high wear resistance is required for the top material.

  On the other hand, as shown in FIG. 2, when the lift arms 52a and 52b are stopped, it is not preferable that the speed reducer is reversely rotated by a load.

From this point of view, the input side is preferable as the installation place of the torque limiter. Therefore, in the present invention, a torque limiter 27 is provided on the input side as between the pulley 14 and the eccentric shaft 20 as shown in FIG.
From this point of view, the input side is preferable as the installation place of the torque limiter. Therefore, in the present invention, a torque limiter 27 is provided on the input side as between the pulley 14 and the eccentric shaft 20 as shown in FIG.

When the load becomes larger than a predetermined value, the torque limiter 27 operates and the transmission of power from the pulley 14 to the eccentric shaft 20 stops.
In addition, even if the pulley 14 tries to rotate due to a load applied to the output shaft 13, the torque limiter 27 takes charge of a value obtained by dividing the load by the reduction ratio (the power transmission efficiency is 100%). Reversal can be prevented.

  For example, when the reduction ratio is 50 and a torque of 100 Nm acts on the output shaft, the reduction gear does not reverse by the load as long as the torque limiter 27 does not operate up to a torque of 2 Nm. That is, the torque limiter 27 functions as a brake. The braking force required for this brake has the advantage of requiring a small value corresponding to the reduction ratio.

  Of course, the configuration including the torque limiter 27 is not limited to the configuration described above, and may be a configuration as shown in FIG.

In the configuration shown in FIG. 8, the input shaft 80 and the output shaft 90 are provided coaxially, and an eccentric portion 83 that forms an eccentric shaft is formed at the end of the input shaft 80. The eccentric portion 83 gives an eccentric rotational motion to the first gear 84 via the spherical bearing 91c.
A pin loose fitting hole 89 is formed in the first gear 84, and a regulation pin 88 is loosely fitted in the pin loose fitting hole 89. The restriction pin 88 is fitted on an output extraction plate 93 provided on the output shaft 90.

  A second gear 86 is provided opposite to the first gear 84, and the second gear 86 is provided by being fitted to the casing 92b.

  Further, a biasing member 82 that biases the first gear 84 is fixedly provided on the input shaft 80 so as to rotate integrally with the input shaft 80. The urging member 82 includes a torque value setting spring 82b including a leaf spring connected to the input shaft 80, and a contact portion 82a that contacts the first gear 84 via a bearing 91b.

  Note that the length of the contact portion 82a (the length in the rotation axis direction) is set to a different length (L1> L2). The longer abutting portion 82a is provided so as to coincide with the eccentric direction. Therefore, the tooth portion 85 of the first gear 84 on the side urged by the contact portion 82 a in the eccentric direction partially meshes with the tooth portion 87 of the second gear 86.

  Since the first gear and the second gear in the reduction gear described so far have an internal relationship, the number of teeth is limited. The first gear 84 and the second gear 86 in the reduction gear according to the present embodiment are Since there is no such inclusion relationship and it is provided in an opposing relationship, there is no structural limitation on the number of teeth.

  Further, when the load applied to the output shaft 90 changes and becomes larger than the urging value by the torque value setting spring (torque limiter) 82b urging the first gear 84 to the second gear 86, the teeth of the first gear 84 are increased. The portion 85 moves against the torque value setting spring 82b from the tooth portion 87 of the second gear 86 (moves in the direction of the arrow K), and power transmission is adjusted. That is, when a certain torque is reached, no more torque is output from the output shaft 90.

  Next, the sixth embodiment of the present invention will be described. The present embodiment relates to materials for the first gear and the second gear used in the reduction gear.

  As the material of such a gear, stainless steel, brass, cast iron, aluminum or the like can be used, and the manufacturing method thereof can be cutting, pressing, die casting, sintered metal, or the like.

  As industrial plastics, general engineering plastics and super engineering plastics such as polyacetal, polycarbonate and polybutylene terephthalate, and thermosetting resins such as phenol resins and epoxy resins can be used. Molding, cutting, etc. can be used.

  As described above, since the first gear and the second gear are cycloid gears, the teeth basically do not slide, but it is considered that some sliding actually occurs for reasons such as manufacturing accuracy. In such a case, an oil-containing resin may be used as a material in order to help the sliding surface slide.

A large reduction ratio means that a large torque is output, but the value varies depending on the product used.
In addition, since a large load is repeatedly applied to the first gear through which the regulation pin is inserted, a material having higher mechanical strength than the second gear may be required. In such a case, for example, the first gear can be made of metal and the second gear can be made of industrial plastic, or vice versa.

It is sectional drawing of the reduction gear applied to description of the 1st Embodiment of this invention. It is a figure explaining a lifter as an example of application of a reduction gear concerning the present invention. It is sectional drawing of the reduction gear applied to description of the 2nd Embodiment of this invention. It is sectional drawing of the reduction gear applied to description of the 3rd Embodiment of this invention. It is sectional drawing of the reduction gear applied to description of the 4th Embodiment of this invention. It is sectional drawing of the reduction gear applied to description of the 5th Embodiment of this invention. It is a figure which shows the example of a torque limiter. It is sectional drawing of the reduction gear of the structure changed into FIG. It is a figure which shows the example of the reduction gear of the double axis | shaft output comprised by the conventionally used spur gear.

Explanation of symbols

10a to 10c Reduction gear 11 Motor 12 Timing belt 13, 37, 48, 76 Output shaft 14, 63, 64 Pulley 20 Eccentric shaft 21, 83 Eccentric portion 22 First gear 23 Restriction pin 24 Second gear 25e Bearing 25b Bearing 25c, 25d Bearing 25a Bare bearing 26 Pin loose hole 27 Torque limiter 28 Casing 30 Casing 31 Power transmission gear 31 Power transmission gear (power transmission mechanism)
32 Motor shaft 33 Eccentric gear (Eccentric shaft)
34, 44, 69, 88 Restriction pin 35, 42, 84 First gear 36, 45.86 Second gear 38, 43, 89 Pin loose hole 41a Stator 41b Rotor 41c Rotor coil 41d Rotor eccentric part 51 connecting bar 52a, 52b lift arm 53 speed reducer mounting plate 54b bottom plate 54a space (side plate 56a, 56b arm shaft 65 front stage eccentric shaft 66 front stage eccentric part 67 front stage first gear 68 front stage pin loose fitting hole 70 front stage second gear 71 Second-stage gear tooth part 72 Second-stage eccentric part 73 First-stage gear 74 Second-stage pin loose-fitting hole 75 Second-stage second gear 80 Input shaft 81 Torque value setting spring 82 Biasing member 82a Contact part 82b Torque value setting spring 90 Output shaft 91c Spherical bearing 93 Output extraction plate

Claims (8)

An eccentric shaft that converts rotational motion into eccentric rotational motion and through which the output shaft is inserted;
A first gear that is eccentrically moved by the eccentric shaft;
A second gear that is inserted through and connected to the output shaft, and that partially meshes with the first gear in accordance with the eccentric motion of the first gear;
A reduction gear comprising: a regulation pin for regulating the rotation of the first gear and allowing the second gear to rotate while allowing the eccentric gear to swing eccentrically. An eccentric shaft that converts rotational motion into eccentric rotational motion and through which the output shaft is inserted;
A first gear that is eccentrically moved by the eccentric shaft;
A second gear provided immovably and partially meshed with the first gear with an eccentric motion of the first gear;
An output take-out member connected through an output shaft and rotated by the rotation of the first gear;
A speed reduction mechanism comprising: a restriction pin that spans between the first gear and the output take-out member, at least one of which is swingably mounted and transmits the rotation of the first gear to the output take-out member. Machine. An eccentric shaft that converts rotational motion into eccentric rotational motion;
A first gear having internal teeth and driven by the eccentric shaft to perform an eccentric motion;
A second gear having external teeth and partially meshed with the first gear with the eccentric movement of the first gear;
A reduction gear comprising: a regulation pin for regulating the rotation of the first gear and allowing the second gear to rotate while allowing the eccentric gear to swing eccentrically. An eccentric shaft having an eccentric portion that converts rotational motion into eccentric rotational motion, a first gear that performs eccentric swing motion by the eccentric shaft, and the first gear that accompanies the eccentric motion of the first gear. A plurality of reduction gears each including a second gear that partially meshes with the gear;
The second gear in the speed reducer on the front stage also serves as the eccentric portion in the speed reducer on the rear stage, and a regulation pin that regulates the rotation of the first gear in all the speed reducers. A reduction gear characterized by being loosely fitted in and inserted.   The rotational motion transmitted to the eccentric shaft is the rotational motion of the motor, and the rotor of the motor is provided integrally with the eccentric shaft, or the eccentric shaft is formed on the rotor. The speed reducer according to any one of claims 1 to 4, wherein the speed reducer. An eccentric shaft that converts rotational motion into eccentric rotational motion;
A first gear that performs an eccentric oscillating motion by the eccentric shaft;
A second gear partially meshed with the first gear in accordance with the eccentric movement of the first gear;
A regulation pin that regulates the rotation of the first gear while allowing the eccentric gear to swing eccentrically, and rotates the second gear.
A torque limiter mounted on the eccentric shaft, and configured to slip when the output shaft driving torque exceeds a predetermined value so that rotational power from the motor is not transmitted to the eccentric shaft. Decelerator. An eccentric shaft that converts rotational motion into eccentric rotational motion;
A first gear that is eccentrically oscillated by the eccentric shaft and is swingable in the axial direction;
A second gear that includes a tooth portion facing the tooth portion of the first gear on a surface perpendicular to the rotation axis, and that partially meshes with the first gear with the eccentric motion of the first gear;
A regulation pin that regulates the rotation of the first gear while allowing the eccentric gear to swing eccentrically, and rotates the second gear.
And a biasing member that is rotatably provided integrally with the eccentric shaft, and biases the first gear with a predetermined force to partially mesh the first gear and the second gear. And reducer. An eccentric shaft that converts rotational motion into eccentric rotational motion;
A first gear that performs an eccentric oscillating motion by the eccentric shaft;
A second gear partially meshed with the first gear in accordance with the eccentric movement of the first gear, and
One of the first gear and the second gear is made of resin, and the other is made of metal.