JP3568053B2 - Transmission - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a transmission that can achieve a high reduction ratio in one step.
[0002]
[Prior art]
Conventionally, various types of speed reduction mechanisms have been proposed to reduce high-speed rotation to low-speed rotation, and the following transmissions are known.
[0003]
(1) First conventional example A transmission in which a plurality of gear trains such as a spur, umbrella, worm gear, etc. are used, or in which a planetary gear is used to reduce the speed.
[0004]
(2) Second Conventional Example A transmission using a harmonic drive mechanism, which is one of mechanisms for decelerating using a difference in the number of teeth.
[0005]
(3) Third conventional example A transmission using an elastically deformable wave gear described in Japanese Patent Application Laid-Open No. Sho 63-214544, which is another mechanism for reducing the speed by utilizing the difference in the number of teeth.
[0006]
(4) Fourth conventional example A universal joint described in JP-A-4-191546 and JP-A-5-99283, which is another one of the mechanisms for decelerating using the difference in the number of teeth, or using a ball. A transmission that pivots the oscillating bevel gear.
[0007]
FIG. 5 shows the above-described third conventional transmission. In FIG. 5, reference numeral 30 denotes a wave gear, and a tooth portion 30A is formed around an end face. Reference numeral 31 denotes a speed change gear, which is formed with a tooth portion 31A having a different number of teeth from the tooth portion 30A around the end face. Reference numeral 32 denotes a rotating shaft of a motor serving as an input shaft, reference numeral 33 denotes an arm, reference numeral 34 denotes a roller provided at the tip of the arm 33, and reference numeral 35 denotes a chassis. In this transmission, when the wave gear 30 pressed by the roller 34 undergoes elastic deformation, the teeth 30A of the gear 30 mesh with the teeth 31A of the transmission gear 31, and the arm 3 is rotated about the rotation axis. , The meshing position is sequentially shifted.
[0008]
Here, assuming that the wave gear 30 is fixed in the rotation direction, the speed change gear 31 is rotated by one pitch of the gear. Therefore, for example, when the number of teeth of the wave gear 30 is 64 and the number of teeth of the transmission gear 31 is 66, when the arm 33 makes one rotation, the transmission gear 31 has two teeth. It has been done. That is, it means that it has been rotated by 1/33 (2/66).
[0009]
FIG. 6 shows the above-described fourth conventional transmission. In FIG. 6, 40 is a casing, 41 is an input shaft, 42 is an input rotor, 43 is an input gear, 44 is a rotating bearing ball, 45 is an output shaft, 46 is a detent roller pin, 47 is a slit groove, and 48 is an output side. Show gears. When the input shaft 41 rotates, the input rotor 42 fixed to the input shaft 41 and having the inclined end face also rotates, and the input-side gear 43 that is in sliding contact with the input shaft 41 swings about the rotary bearing ball 44.
[0010]
The input side gear 43 does not rotate because the rotation stopping roller pin 46 attached to the outer periphery is fitted in the slit groove 47 provided in the casing 40. When the input rotor 42 that slides on the back surface of the input gear 43 makes one rotation, the input gear 43 swings, and the output gear 48 that partially meshes with the input gear 43 rotates by the number of teeth.
[0011]
For example, when the number of teeth of the input side gear 43 is 100 and the number of teeth of the output side gear 48 is 99, when the input side gear 43 swings once, there is one tooth difference from the output side gear 48. Therefore, the number of teeth is excessively increased. In other words, this means that it has rotated 1/100.
[0012]
[Problems to be solved by the invention]
However, the following problems are pointed out in the above-described conventional example.
[0013]
(1) First Conventional Example If a flat, bevel gear, or planetary gear is used, a reduction ratio of 1/2 to 1/3 per gear is appropriate. A plurality of gear trains are required, and there is a difficulty in increasing the size.
[0014]
When a worm gear is used, high speed reduction can be obtained in one stage, but the transmission efficiency is generally poor at 40%.
[0015]
(2) Second Embodiment Although a high speed reduction ratio can be obtained in one stage using a harmonic drive mechanism, it is difficult to make the thickness thin, and the number of parts increases, such as using ball bearings. There are disadvantages that are expensive.
[0016]
(3) The third conventional example is characterized by an elastically deformable wave gear, which uses an elastic body for the gear, constantly deforms the gear, and forcibly engages the opposing gear for use. Also, it is applied to, for example, consumer-use and small-sized products that have low torque and do not require much rotation accuracy and durability in view of the physique of the constituent components.
[0017]
(4) Fourth conventional example Using an oscillating gear and an output bevel gear formed of rigid members, regulating the oscillating gear in the rotation direction using a universal bearing or ball-mounted pivot bearing and a pin. In this configuration, the shaft of the output bevel gear opposing is the output shaft.In this configuration, the rigidity of the members forming the oscillating gear and the output bevel gear, especially withstands a high load from the output shaft side. In view of the mechanism to be used and the physical size of the constituent parts, the present invention is intended for high torque and durable products, for example, industrial and heavy machinery products.
[0018]
Therefore, when used as a small transmission, it is difficult to reduce the size, especially the thickness, and because the roller pin is used for rotation control, the roller pin swings during rotation and hits the slit groove of the casing, causing play. This leads to the occurrence of backlash and uneven rotation due to backlash during startup.
[0019]
An object of the invention according to the present application is to achieve a high reduction ratio in one stage with a transmission efficiency close to that of a spur gear, to obtain a stable rotation without a backlash of an output shaft at the time of startup, and to have a simple structure and durability. It is an object of the present invention to provide a transmission which is excellent in cost and can be manufactured at low cost.
[0020]
Means and action for solving the problem
A first configuration for realizing the object of the invention according to the present application is, as described in claim 1, a first gear fixed to a casing and a first gear having a difference in the number of teeth from the first gear. A transmission member fixed coaxially to the output shaft and having an outer peripheral portion fixed to the second gear, and the second gear while rotating integrally with the input shaft. and a pressing means are engaged by pressing a portion of the gear portion to the first gear, pressing with pressing means to press the second gear, the second in Rukoto is elastically deformed to the transmission member a a speed change gear for swinging around its axis of rotation, in transmission, characterized in that the first gear is formed of an elastic member.
[0021]
In this configuration, the second gear is sequentially meshed with the first gear while oscillating due to the bending deformation of the transmission member with the rotation of the pressing means, and when the input shaft makes one rotation, the second gear becomes the first gear. By rotating by the number of teeth different from the gear, a high reduction ratio can be obtained. Also, since the gears themselves are not bent and elastically deformed, they can be applied to high-torque gear shifting, and have good transmission efficiency, and a high reduction ratio can be obtained in one stage with a transmission efficiency close to that of a spur gear. Along with simplification, it is possible to reduce the size of equipment using the same. In addition, the number of parts is small, assembly is easy, and it can be manufactured at low cost.
[0022]
In particular, since the first gear is formed of an elastic member, backlash between the gears can be absorbed, vibration and noise can be reduced, and the first gear that does not oscillate has a thickness equal to that of the first gear. Since it is elastically deformed in the direction, there is no particular effect on the transmission efficiency.
[0023]
A second configuration for realizing the object of the present invention according to the present application is characterized in that, in the first configuration, a stabilizing unit that stabilizes a swing center of the second gear is provided in the first configuration. Transmission.
[0024]
With this configuration, the second gear has good meshing with the first gear, and a stable rotation output without rotation unevenness can be obtained.
[0025]
According to a third configuration for realizing the object of the invention according to the present application, as described in claim 3, in claim 1 or 2, the elastic member forming the first gear or the second gear is made of rubber or rubber. The transmission is characterized by being polyurethane.
[0026]
With this configuration, a good elastic force can be obtained without using a special elastic member.
[0027]
According to a fourth configuration for realizing the object of the invention according to the present application, as set forth in claim 4, in claim 1, 2 or 3, the tooth shape of the first gear is substantially bevel gear shape. Transmission.
[0028]
With this configuration, the second gear has good meshing with the first gear, and a stable rotation output without rotation unevenness can be obtained.
[0031]
According to a fifth configuration for realizing the object of the invention according to the present application, as set forth in claim 5 , in claim 1, 2, 3 or 4 , the pressing means has an inclined surface inclined with respect to the rotation axis. The transmission is characterized in that the inclined surface is pressed against the second gear as a sliding surface.
[0032]
With this configuration, the configuration of the pressing unit can be simplified.
[0033]
Sixth configuration of realizing the object of the invention according to this application, as described in claim 6, according to claim 1, 2, 3 or 4, the transmission apparatus characterized by pressing means is a radial bearing It is in.
[0034]
With this configuration, the second gear can be pressed with low friction.
[0046]
【Example】
FIG. 1 shows a first embodiment of a transmission according to the present invention.
[0047]
Reference numeral 1 denotes a casing, which is coaxially fixed to the tip of the motor body 2. The rotating shaft (input shaft) 2a of the motor main body 2 is inserted into the casing 1, and the rotor 3 is fixed to the tip of the rotating shaft 2a by screwing. A support shaft 5 is attached to the rotor 3 so as to be orthogonal to the rotation shaft 2a of the motor body 2, and a radial bearing 4 is fixed to the support shaft 5 by a set screw 6. Reference numeral 7 denotes an output shaft arranged coaxially with the rotary shaft 2a , which is attached to a casing lid 8 of the casing 1 via a radial bearing 9.
[0048]
Reference numeral 10 denotes a disk-shaped transmission member formed of a thin plate having spring properties, which is coaxially fixed to one end of the output shaft 7 by a screw 10a, and a swing gear 11 is fixed to the outer periphery. As shown in FIG. 4A, the transmission member 10 has a screw hole 10b for a screw 10a formed in a central portion and a screw hole 10c for an oscillating gear formed in an outer peripheral portion. An arc-shaped hole 10d or a semi-circular hole 10e is formed between the holes to allow bending deformation and prevent deformation in the circumferential direction.
[0049]
The transmission member 10 is formed of an elastically deformable material such as a metal and a synthetic resin.
[0050]
Reference numeral 11 denotes an oscillating gear in which a radial bevel gear or a gear portion (number of teeth n ₁ ) similar to a bevel gear such as a triangular tooth is formed on one side of the annular portion, and is fixed to the outer peripheral portion of the transmission member 10. Have been. The other side 11a of the oscillating gear 11 is in contact with the outer peripheral surface of the radial bearing 4, and the other side 11a is formed on an inclined surface to make good contact with the radial bearing 4. are doing. The swing gear 11 is formed of a suitable material such as a metal or a synthetic resin.
[0051]
Reference numeral 12 denotes an annular fixed gear formed of an elastic body such as rubber or polyurethane, which is fixed to the casing lid 8 by baking or bonding. The fixed gear 12 faces the gear portion of the oscillating gear 11 and has a gear portion (the number of teeth n ₂₎ having a tooth number difference from the gear portion of the oscillating gear 11. ) Is formed. With respect to the gear portion of the fixed gear 12, the gear portion of the oscillating gear 11 partially deforms the transmission member 10 by elastically deforming the transmission member 10 by a pressing mechanism including a radial bearing 4, a support shaft 5, and a set screw 6. Are engaged with the gear portion of the fixed gear 12. By forming this fixed gear with an elastic body, when the rocking gear 11 is meshed with the fixed gear 12 by the pressing means, both gear portions are meshed without play.
[0052]
In this embodiment having the above-described configuration, when the rotating shaft 2a of the motor rotates, the pressing mechanism including the radial bearing 4 and the like also rotates integrally with the rotating shaft 2a. Then, the radial bearing 4 presses the end of the oscillating gear 11 from the rear, and just causes the oscillating gear 11 to oscillate while elastically deforming the transmission member 10 so that the teeth of the oscillating gear 11 are attached to the casing 1. The gears of the fixed gear 12 are sequentially meshed.
[0053]
Here, the number of teeth n ₁ to 51 of the swing gear 11, when the number of teeth n ₂ of the fixing gear 12 and 50, the oscillating gears 11 1 rotates the swing, difference in the number of teeth between the fixed gear 12 Since there is one tooth, the teeth are additionally meshed by the difference in the number of teeth. That is, when the rotation shaft 2a makes one rotation, the swing gear 11 makes 1/50 rotation. The transmission member 10 that connects the oscillating gear 11 and the fixed gear 12 absorbs a bending distortion at the time of oscillating by its elastic force, and transmits the rotation to the output shaft 7 accurately. Further, component tolerances constituting the transmission, Bakkura' sheet is produced by assembling adjustment, since the fixed gear 12 formed of an elastic material, is absorbed by the elastic deformation in the thickness direction of the fixing gear 12, also thereby vibrating Generation and noise generation are also reduced.
[0054]
FIG. 2 shows a second embodiment of the present invention.
[0055]
In the first embodiment described above, the pressing means is constituted by the radial bearing 4, the support shaft 5, and the set screw 6. In the present embodiment, however, the cylindrical pressing member 20 is attached to the rotary shaft 2a of the motor. Is fixed, and the open end surface 20a of the pressing member 20 is formed into a cut-out shape that is cut obliquely, is brought into contact with the other surface side of the oscillating gear 11, and is engaged with a part of the gear portion of the fixed gear 12 sequentially. I have to.
[0056]
Note that a thrust bearing may be provided on the open end surface 20 a of the pressing member 20 to reduce sliding resistance with the fixed gear 12.
[0057]
Further, the pressing member 20 and the oscillating gear 11 may be made of different metals for preventing high-speed gear shifting, or different materials such as a metal and a synthetic resin, or a combination of different synthetic resins for a low torque. It can be formed of an appropriate material according to the purpose of use.
[0058]
Further, in the first and second embodiments described above, the rotor including the pressing means is rotationally balanced by a balancer (not shown).
[0059]
FIG. 3 shows a third embodiment of the present invention.
[0060]
In the above-described first and second embodiments, the swing gear 11 performs the swing motion of sequentially tilting only by the elastic force of the transmission member 10, but in the present embodiment, the swing gear 11 is provided at one end of the output shaft 7. A hemispherical hemispherical top part 22 is formed, and a receiving member 23 having a hole 23 a fitted into the hemispherical top part 22 is fixed to the swing gear 11.
[0061]
Therefore, the above-described rocking motion of the rocking gear 11 is regulated by the engagement of the receiving member 23 with the hemispherical top portion 22, and a stable rocking motion can be obtained.
[0062]
In each of the embodiments described above, the radial bearing 4 and the pressing member 20 are used as the pressing means, but the present invention is not limited to this, and may be a ball or the like.
[0063]
Further, although screws are used for coupling between the members constituting the transmission, in consideration of mass productivity, they may be formed by integral molding, insert coupling, or the like using a molding method.
[0064]
【The invention's effect】
According to the first aspect of the present invention, with the rotation of the pressing means, the second gear is sequentially meshed with the first gear while oscillating due to bending deformation of the transmission member, and when the input shaft makes one rotation, The second gear rotates by the difference in the number of teeth from the first gear, and a high reduction ratio is obtained. Since a high reduction ratio can be obtained in one stage, it is possible to reduce the size and simplification of the transmission itself, and to reduce the size of equipment using the transmission. In addition, the number of parts is small, the assembly is easy, and it can be manufactured at low cost.
[0065]
In particular, since the first gear is formed of an elastic member, backlash between the gears can be absorbed, and vibration and noise can be reduced.
[0066]
According to the second aspect of the invention, the second gear has good meshing with the first gear, and a stable rotation output without rotation unevenness can be obtained.
[0067]
According to the third aspect of the invention, a good elastic force can be obtained without using a special elastic member.
[0068]
According to the invention described in claim 4, the second gear has good meshing with the first gear, and a stable rotation output without rotation unevenness can be obtained.
[0070]
According to the invention described in claim 5 , the configuration of the pressing means can be simplified.
[0071]
According to the invention described in claim 6 , the second gear can be pressed with low friction.
[0080]
According to the invention described in claim 11, the member having flexibility, it is possible to obtain a rotational output free of Bakkura' shea, moreover sound, sound insulation against vibration, the vibration damping effect can be obtained.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a first embodiment of a transmission according to the present invention.
FIG. 2 is a sectional view showing a second embodiment.
FIG. 3 is a sectional view showing a third embodiment.
FIG. 4 is a plan view of the transmission member shown in the first embodiment.
FIG. 5 is a perspective view showing a third conventional example.
FIG. 6 is a sectional view showing a fourth conventional example.
[Explanation of symbols]
1 casing 2 motor body 2a rotating shaft (input shaft)
Reference Signs List 3 Rotor 4 Radial bearing 5 Support shaft 6 Set screw 7 Output shaft 8 Casing lid 9 Radial bearing 10 Transmission member 11 Oscillating gear 12 Fixed gear 20 Pressing member 22 Hemisphere top portion 23 Receiving member

Claims (6)

A first gear fixed to the casing, a second gear having a difference in the number of teeth from the first gear, having a spring property, being coaxially fixed to an output shaft, and having an outer peripheral portion formed of the first gear. It has a transmission member which is fixed to the second gear, and a pressing means for a portion of the second gear unit while rotating integrally with the input shaft is pressed against the first gear meshing, pressing pressure A transmission device that presses the second gear by means and elastically deforms the transmission member to swing the second gear about its rotation axis;
A transmission, wherein the first gear is formed of an elastic member. 2. The transmission according to claim 1, further comprising a stabilizing unit that stabilizes a swing center of the second gear. 3. The transmission according to claim 1, wherein the elastic member is made of rubber or polyurethane. 4. The transmission according to claim 1, wherein the first gear has a substantially bevel gear shape. According to claim 1, 2, 3 or 4, wherein the pressing means have an inclined surface inclined with respect to the rotation axis, characterized in that to press the second gear to the inclined surface as a sliding surface Transmission. According to claim 1, 2, 3 or 4, the transmission, wherein said pressing means is a radial bearing.

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