TWM512259U - Direct drive motor with deceleration mechanism - Google Patents

Description

Direct drive motor with speed reduction mechanism

The present invention relates to a direct drive motor with a speed reduction mechanism, and more particularly to a design that enables a low pole direct drive motor to increase the output torque of the motor with a harmonic speed reduction mechanism in a limited space.

Due to the lack of torque, the conventional servo motor usually uses the gear reduction mechanism to exchange the same output power motor for the torque output by reducing the rotation speed. However, the speed reduction mechanism has the backlash problem of the gear, and the volume is too large. The space is much larger than the servo motor volume, so using a direct drive motor is a good choice for miniaturized equipment and lowering costs. The output torque of the direct drive motor is limited by the input current, internal magnetic flux density and motor size. The larger the motor size, the larger the output torque, but the higher the price. Therefore, the factor of motor size is limited by equipment space and cost considerations.

When the motor is applied to the shaft joint of the robot arm in the field of mechanical automation, three important requirements must be considered. One is that the output torque of the motor is large, and the speed of the motor output is low. Finally, The motor is small in size. The larger the value of the motor output torque, the more it contributes to the load capacity of the robot arm; the low motor speed can reduce the noise value without the doubt of overheating, and the motor has good effect in frequent positive and negative reversal. The operation efficiency is high, and the speed reduction mechanism can accurately position without a large reduction ratio; the motor is small in size, the motor cost can be appropriately controlled, and the structural design of the shaft joint of the mechanical arm is beneficial.

The shaft joints of the traditional mechanical arm are mostly applied by a Harmonic Drive (HD) using a metal elastic mechanics. The Flex Spline used in the HD is a cup or a cap. The thin metal shell elastomer has a tooth shape cut at its outer peripheral opening portion and a diaphragm at the bottom of the tooth type. Since the flexible rack is made of special steel with extremely high fatigue strength, and the HD transmission mode is different from the meshing power transmission mode of the general gear, the tooth backlash value is extremely small, so the machining of the metal tooth type, It must be applied with special tools. In addition to the difficulty of obtaining tools and special steel materials, the cost is not high. If the position of the formed tooth type is not suitable for the tool, it will increase the difficulty of processing and the production cost.

In addition, since the entire HD structure is composed of a combination of metal materials, when assembled in the middle and end portions of the robot arm, the load torque at the joint of the front end of the arm is increased, resulting in a poor effective load value of the robot arm.

To this end, combining the above-mentioned elements for the joints of the mechanical arm, this creation is an innovative design for the direct drive motor with a speed reduction mechanism, which is light in weight, small in size, easy to manufacture, low in price, large in output torque, and accurate in positioning. The advantage of the speed reduction mechanism makes the direct drive motor more suitable for the application of the mechanical arm shaft joint.

The purpose of the present invention is to provide a direct drive motor design with a speed reduction mechanism that directly stores a low pole number direct drive motor in a harmonic speed reduction mechanism, thereby obtaining a direct output motor with a better output torque. The direct drive motor has the design goal of low cost, high torque and small volume.

In order to achieve the above object, a direct drive motor having a speed reduction mechanism is provided. The preferred embodiment includes: a drive motor and a speed reduction mechanism, wherein the direct drive motor is disposed in the speed reduction mechanism, and includes a rotor assembly. And a stator assembly necessarily located within the rotor assembly; the stator assembly having a fixed shaft, a plurality of magnetic poles disposed about the fixed shaft, and coils respectively wound around the magnetic pole; the rotor assembly including a housing And a plurality of magnets attached to the inner side of the outer casing; and the two ends of the outer casing are respectively provided with a bearing, and the bearing is arranged to be supported on the fixed shaft. The speed reduction mechanism includes at least one internal tooth difference ring, an external tooth difference ring and a harmonic generator; the internal tooth difference ring has an outer ring body formed of a first material, and the inner ring surface of the outer ring body is provided with an or One or more attachment portions, and an inner ring body composed of a second material different from the first material, the inner ring body having internal teeth coaxially coupled to the inner annular surface of the outer ring body and fixed The outer toothed ring is rotatably disposed in the inner toothed ring, the outer ring surface has external teeth matching the inner teeth; the harmonic generator has a cam, and the cam is disposed at the In the outer tooth difference ring, and the direct drive motor is coupled in the cam, the outer casing of the rotor assembly drives the cam, and the cam pushes a part of the outer teeth of the outer toothed ring to engage in a part of the inner tooth difference ring tooth.

In the above direct drive motor having a speed reduction mechanism, the fixed shaft is a hollow shaft having a through hole communicating with both ends in the center.

In the above direct drive motor having a speed reduction mechanism, the outer tooth difference ring is a flexible outer tooth difference ring.

In the above direct drive motor with a speed reduction mechanism, the harmonic generator has an elliptical cam, and the cam faces at both ends of the elliptical cam push the two outer teeth of the outer toothed ring to engage the two parts of the inner tooth difference ring Internal teeth.

In the above direct drive motor having a speed reduction mechanism, the outer tooth difference ring is a rigid outer tooth difference ring.

In the above direct drive motor with a speed reduction mechanism, the harmonic generator has an eccentric cam, and a cam surface of the eccentric cam pushes a part of the external teeth of the external tolerance ring to engage a part of the internal teeth of the internal tooth difference ring.

In the above direct drive motor with a speed reduction mechanism, the attachment portion of the internal tooth difference ring is a bump or a groove.

In the above-mentioned direct drive motor with a speed reduction mechanism, one end of the external tooth difference ring is provided with an elastic folding ring, the elastic folding ring has a fixing ring having a diameter larger than the outer tooth difference ring, and is integrally formed or assembled on the fixing ring. An elastic fold between the end of the outer toothed ring.

The direct drive motor with the speed reduction mechanism is arranged, so that the inner tooth difference ring is sleeved on the outer side of the bearing of the harmonic generator, so that the outer teeth of the inner tooth difference ring and the inner teeth of the outer tooth difference ring are partially meshed, and The power output of the direct drive motor is linked to the cam, so that the output torque is increased by the speed reduction mechanism, and the direct drive motor composed of the structure can achieve the design purpose of small number of poles, high torque and small volume.

1‧‧‧Direct drive motor

11‧‧‧Rotor assembly

111‧‧‧Shell

112‧‧‧ magnet

12‧‧‧ stator assembly

121‧‧‧Fixed shaft

122‧‧‧ magnetic pole

123‧‧‧ coil

13‧‧‧ Bearing

2‧‧‧Deceleration mechanism

21‧‧‧ Internal tooth difference ring

211‧‧‧ outer ring

212‧‧‧ Attachment Department

213‧‧‧ Inner ring

214‧‧‧ internal teeth

22‧‧‧ external tooth difference ring

221‧‧‧ external teeth

222‧‧‧ elastic folding ring

223‧‧‧Fixed ring

224‧‧‧Flexible folds

23‧‧‧Harmonic generator

231‧‧‧ cam

232‧‧ ‧roller

3‧‧‧Fixed outer ring

31‧‧‧ Roller

The first figure is a schematic cross-sectional perspective view of a preferred embodiment of the present invention.

The second figure is a schematic side cross-sectional view of a preferred embodiment of the present invention.

The third figure is an exploded perspective view of a preferred embodiment of the present invention.

The fourth figure is an exploded perspective view of a preferred embodiment of the creation speed reduction mechanism.

The fifth figure is a three-dimensional schematic view of the outer ring body of the inner tooth insert.

The sixth figure is a three-dimensional schematic view of the inner ring body of the inner toothed insert.

The seventh figure is a schematic perspective view of a preferred embodiment of the creation speed reduction mechanism.

The eighth figure is a schematic cross-sectional view of a preferred embodiment of the creative elastic folding ring.

The ninth figure is a schematic diagram of the meshing state of the outer tooth difference ring and the inner tooth difference ring.

The structural features and other functions and purposes of the present invention are described in detail below with reference to the accompanying drawings. Referring to the first and second figures, the direct drive motor with the speed reduction mechanism is mainly used to make the external direct drive motor. 1 is disposed in the speed reduction mechanism 2 to obtain a better output torque, wherein: as shown in the second and third figures, the direct drive motor 1 preferably includes a rotor assembly 11 and must be located in the rotor assembly. Total stator in 11 Into 12. The stator assembly 12 has a stationary fixed shaft 121, a plurality of magnetic poles 122 fixed to the circumference of the hollow shaft 121, and coils 123 wound around the magnetic poles 122, wherein the fixed shaft 121 preferably has a communication center. The hollow shaft of the through hole at the end. The rotor assembly 11 includes a housing 111 and a plurality of magnets 112 attached to the inner side of the housing 111. The two ends of the housing 111 are supported by the two bearings 13 on the fixed shaft 121 or other components. When the coil 123 is turned into 12, the rotor assembly 11 can be driven.

As shown in the second and fourth figures, the preferred embodiment of the speed reduction mechanism 2 includes at least one internal tooth difference ring 21, an external tooth difference ring 22, and a harmonic generator 23. As shown in the fifth and sixth figures, the inner toothed ring 21 is provided with an outer ring body 211 of a first material, and the first material is preferably made of a light metal such as an aluminum alloy. The inner ring surface of the outer ring body 211 is provided with one or more attachment portions 212, and the attachment portion 212 can be any shape of protrusions or grooves/holes; and the inner annular surface of the outer ring body 211 is different from the first material. The inner ring body 213 of the second material is preferably a plastic material suitable for mold molding, such as engineering plastics, and the outer ring body 211 can be placed in the mold, and the engineering plastic is embedded by the injection molding method. The inner ring surface of the outer ring body 211 is formed, and the inner ring surface of the inner ring body 213 is simultaneously molded with the inner teeth 214, and is fixedly coupled to the attaching portion 212 of the outer ring body 211.

As shown in the fourth and seventh figures, the outer toothed ring 22 is coaxially or eccentrically disposed in the inner toothed ring 21, and has an outer tooth 221 on the outer ring surface, and the outer tooth 221 has fewer teeth than the corresponding one. The number of teeth of the internal teeth 214 of the internal tooth difference ring 21 forms a difference in the number of teeth. The harmonic generator 23 is mainly a device connected to the power input end, and includes a cam 231 or an eccentric wheel, and a plurality of rollers 232 or an axis. The cam 231 or the eccentric is coaxially or eccentrically disposed in the outer toothed ring 22, and a plurality of rollers 232 are arranged between the cam surface around the cam 231 and the inner annular surface of the outer toothed ring 22, This causes the cam 231 and the roller 232 to push a part of the external teeth 221 of the external toothed ring 22 to engage a part of the internal teeth 214 of the inner toothed ring 21.

With the above-described direct drive motor 1 being provided in the feature of the speed reduction mechanism 2, the cam 231 of the harmonic generator 23 is sheathed on the outer periphery of the outer casing 111 of the direct drive motor 1 (as shown in the first and second figures), and the external teeth The differential ring 22 is sleeved on the periphery of the plurality of rollers 232 or the bearing of the harmonic generator 23, so that the outer teeth 221 of the outer toothed ring 22 and the inner teeth 214 of the inner toothed ring 21 are partially meshed, and the direct drive The rotor assembly 11 of the motor 1 can be directly coupled with the cam 231, so that the output torque of the direct drive motor 1 is increased by the speed reduction mechanism 2, so that the direct drive motor with the speed reduction mechanism can achieve a small number of poles and a large output torque. The effect of shrinking size.

Furthermore, the inner tooth difference ring 21 and the outer tooth difference ring 22 are combined with the rotor assembly 11 of the direct drive motor 1 to drive the motor. Therefore, the inner tooth difference ring 21 and the outer tooth difference ring 22 can be both ring bodies. Supporting the servo through a fixed outer ring 3 (refer to the second figure), the fixed outer ring 3 is made of a light-weight aluminum alloy metal material, and is arranged in a cross arrangement with the inner tooth difference ring 21 The roller 31 is supported so that the internal tooth difference ring 21 can obtain a stable servo in both the shaft and the radial direction, so that when the direct drive motor 1 is applied to the robot arm, the advantages of high rigidity support and positioning are achieved, and the machine can be improved. Arm positioning accuracy.

The cam 231 of the aforementioned harmonic generator 23 can be directly fitted around the outer casing 111 of the rotor assembly 11 and rotate together with the outer casing 111. Since the stator assembly 12 of the direct drive motor 1 is fixed by a fixed shaft 121, the fixed shaft 121 is preferably embodied as a hollow shaft, so that the speed reduction mechanism 2 disposed outside the direct drive motor 1 does not output power. Interference to the two ends of the fixed shaft 121, so that the fixed shaft 121 (the through hole of the hollow shaft) can provide the relevant wire passage, so that the end wire group of the multi-axis robot arm can have a better wiring design, and the mechanical arm has a simple appearance. There is no confusing line of tangled lines to hinder the operation.

Referring to the first, second and eighth figures, the outer toothed ring 22 can be integrally formed with an elastic folding ring 222 at the axial side end of the ring body. The elastic folding ring 222 has a diameter larger than The fixing ring 223 of the outer toothed ring 22 and the elastic folding portion 224 integrally formed or assembled between the fixing ring 223 and one end of the outer toothed ring 22, so that the outer toothed ring 22 and the inner tooth are made by the elastic flange 224 When the differential ring 21 is meshed in multiple sections, it can have a more radial elastic action and can be combined with the fixed outer ring 4. As shown in the ninth embodiment, the external toothed ring 22 is supported by the harmonic generator 23, and the opposite sides of the 180 degrees are simultaneously meshed with the internal toothed ring 21 due to The outer tooth difference ring 22 is integrally formed of engineering plastics. In addition to the elastic property of the material, the outer elastic hem 224 can be used to assist the tooth difference creeping rotation during multi-section meshing, and the outer teeth The torque resistance of the meshing transmission of the inner tooth 214 and the inner tooth 214 can also be improved by widening the meshing tooth width. Therefore, in the present creation, the function of the external tooth difference ring 22 on the harmonic reducer can fully realize the application flawlessness, and at the same time, due to the selection of the lightweight material, the shifting device can easily achieve weight reduction. For the purpose of not losing the strength requirement due to the choice of materials, obtaining a between the weight reduction and the strength requirement The best balance.

In addition, since the internal teeth 214 of the internal tooth difference ring 21 and the external teeth 221 of the external tooth difference ring 22 are formed in the mold in advance, if the tooth shapes of the internal teeth 214 and the external teeth 221 are to be changed, only It is easy to achieve the mold cutting of the mold, which is a method that simplifies the manufacturing process and reduces the cost. It is not necessary to have a tooth type that is made of metal as a conventional one, and it is necessary to prepare various types of tooth forming and forming tools in order to cope with the needs of various tooth ratios, so that the manufacturing cost cannot be reduced.

In summary, the direct drive motor with the speed reduction mechanism of this creation has been practical and creative, and its technical means are also novel and undoubted, and the effect and design purpose are in line with the fact that it has been reasonably improved. To this end, a new type of patent application is filed in accordance with the law, but the bureau is requested to give a detailed examination and grant the patent as a prayer.

1‧‧‧Direct drive motor

11‧‧‧Rotor assembly

111‧‧‧Shell

112‧‧‧ magnet

12‧‧‧ stator assembly

121‧‧‧Fixed shaft

13‧‧‧ Bearing

2‧‧‧Deceleration mechanism

21‧‧‧ Internal tooth difference ring

211‧‧‧ outer ring

213‧‧‧ Inner ring

214‧‧‧ internal teeth

22‧‧‧ external tooth difference ring

221‧‧‧ external teeth

222‧‧‧ elastic folding ring

223‧‧‧Fixed ring

224‧‧‧Flexible folds

23‧‧‧Harmonic generator

231‧‧‧ cam

232‧‧ ‧roller

3‧‧‧Fixed outer ring

31‧‧‧ Roller

Claims (8)

A direct drive motor having a speed reduction mechanism, comprising a drive motor and a speed reduction mechanism, wherein: the direct drive motor is disposed in a speed reduction mechanism, comprising a rotor assembly and a stator assembly located in the rotor assembly; The stator assembly has a fixed shaft, a plurality of magnetic poles disposed around the fixed shaft, and coils respectively wound around the magnetic poles; the rotor assembly includes a casing, and a plurality of magnets attached to the inner side of the casing And a bearing is disposed on the two ends of the housing, the bearing is disposed to be supported on the fixed shaft; the speed reduction mechanism includes at least one internal tooth difference ring, an external tooth difference ring and a harmonic generator; the internal tooth difference ring has An outer ring body of a first material, the inner ring surface of the outer ring body is provided with one or more attachment portions, and an inner ring body composed of a second material different from the first material, the inner ring body has An inner tooth coaxially coupled to an inner annular surface of the outer ring body and fixedly coupled to the attachment portion; the outer differential ring is rotatably disposed in the inner tolerance ring, and the outer annular surface has Matching the external teeth of the internal tooth; the harmonic The generator has a cam disposed in the outer toothed ring, and the direct drive motor is coupled in the cam, the outer casing of the rotor assembly drives the cam, and the cam pushes a portion of the outer tooth of the outer toothed ring Engaging a portion of the internal teeth of the internal tooth difference ring. A direct drive motor having a speed reduction mechanism according to claim 1, wherein the fixed shaft is a hollow shaft having a through hole communicating with the two ends in the center. a direct drive motor having a speed reduction mechanism according to claim 1, wherein the outer teeth The difference ring is a flexible external tooth difference ring. The direct drive motor with a speed reduction mechanism according to claim 3, wherein the harmonic generator has an elliptical cam, and the cam faces at both ends of the elliptical cam push the two external teeth of the outer toothed ring to engage the inner teeth. The two parts of the inner ring of the difference ring. A direct drive motor having a speed reduction mechanism according to claim 1, wherein the outer tooth difference ring is a rigid outer tooth difference ring. A direct drive motor having a speed reduction mechanism according to claim 5, wherein the harmonic generator has an eccentric cam, and a cam surface of the eccentric cam pushes a part of the external teeth of the outer toothed ring to engage a part of the inner tooth difference ring Internal teeth. The direct drive motor with a speed reduction mechanism according to any one of claims 1 to 6, wherein the attachment portion of the internal tooth difference ring is a bump or a groove. The direct drive motor with a speed reduction mechanism according to any one of claims 1 to 6, wherein one end of the outer toothed ring is provided with an elastic folding ring, and the elastic folding ring has a fixing ring having a diameter larger than the outer tooth difference ring. And an elastic fold integrally formed or assembled between the retaining ring and one end of the outer toothed ring.