TW201902091A - Linear drive system - Google Patents

Abstract

The present invention discloses a linear driving system including a motor, a screw shaft and a table. The motor comprises a rotor, a stator and a ball bearing. The stator comprises a shaft part and a spiral part. The shaft part and the spiral part include an accommodation space in communication with the shaft part and the spiral part. One end of the spiral part includes a first helical protrusion on the inner surface thereof. The screw shaft is coaxially coupled with the rotor. One end of the screw shaft includes a second helical protrusion on the outer surface thereof, and at least portion of the second helical protrusion is accommodated within the accommodation space of the rotor. The table is fixed on the other end of the screw shaft. The first helical protrusion of the spiral part of the rotor is engaged with the second helical protrusion of the screw shaft. When the rotor is rotated, the rotor drives the screw shaft and the table connected with the screw shaft to move forward or backward linearly in the direction of the axial of the rotor.

Description

Linear drive system

This case discloses a linear drive system, especially a linear drive system that does not require a coupling.

Linear drive systems are currently a common technique and are widely used in various fields, such as industrial machinery, precision machine tools, electronic machinery, and transportation machinery. In order to achieve the control of linear motion, the conventional linear drive system mostly uses a motor plus a screw to convert the rotary motion of the motor into the linear motion of the screw.

Please refer to FIG. 1, which is a schematic cross-sectional structure diagram of a conventional linear drive system. As shown, the linear drive system 1 includes a motor 11, a ball screw device 12, a coupling 13, a frame 14, a bearing 15, and a fixed nut 16. The motor 11 includes a rotor 111, a stator 112, and a motor shaft 113. The motor shaft 113 is disposed on the rotor 111. The rotor 111 includes a plurality of permanent magnets 114, and the plurality of permanent magnets 114 are disposed on the rotor 111. The stator 112 includes a plurality of winding coils for transmitting a current and generating a magnetic field interaction with the plurality of permanent magnets 114 of the rotor 111.俾 generates a driving force to rotate the motor shaft 113 of the rotor 111.

The ball screw device 12 is disposed on the frame 14 and includes a screw shaft 121, a slider nut 122, a slide table 123, a linear bearing 124, and a support bearing 125. One end of the screw shaft 121 of the ball screw device 12 is coaxially connected to the motor shaft 113 via a coupling 13. In other words, the coupling 13 is connected between the motor shaft 113 of the motor 11 and the screw shaft 121 of the ball screw device 12, so that the screw shaft 121 of the ball screw device 12 rotates according to the rotation of the motor shaft 113 of the motor 11. The slider nut 122 has threads for engaging the screw shaft 121 and the slider nut 122 with each other. Among them, the slide table 123 is fixedly disposed on the slider nut 122 to carry a load through the slide table 123. A plurality of rolling elements (not shown), such as balls, are provided between the slider nut 122 and the screw shaft 121 so that the screw shaft 121 and the slider nut 122 cooperate with each other.

The linear bearing 124 is disposed on the frame 14 and is connected to the slider nut 122 to limit the rotation of the slider nut 122 and guide the slider nut 122 to move in a linear direction. Accordingly, the slider nut 122 can drive the screw shaft 121 of the ball screw device 12 to rotate along the screw shaft 121 by the motor 11. The support bearing 125 is disposed on the frame 14 to support the other end portion of the screw shaft 121 of the ball bearing 12 and restrict the end portion of the screw shaft 121 so that it cannot move axially relative to the frame 14.

When the motor rotating shaft 113 of the motor 11 and the screw shaft 121 of the ball screw device 12 are coupled together by the coupling 13, one end of the screw shaft 121 can be supported radially by the arrangement of the bearing 15, thereby lifting the motor 11. Of rigidity. In addition, the fixed nut 16 is fixed on the screw shaft 121 and is located between the coupling 13 and the bearing 15 to apply a preload to the bearing 15 to meet the usage requirements of the bearing assembly and limit the bearing 15 to the screw shaft 121 Axial displacement.

However, the linear drive system 1 needs to be provided with a coupling 13 to connect and fix the motor 11 and the screw shaft 121 at the connection point between the motor 11 and the screw shaft 121. However, the rigidity of the coupling 13 makes the linearity The overall rigidity of the drive system 1 is reduced accordingly, and the response speed of the linear drive system 1 cannot be improved, and the cost of the linear drive system 1 is increased due to the addition of the coupling 13. In addition, when the ball screw device 12 of the linear drive system 1 is assembled, in order to increase the overall rigidity, a set of angular ball bearings 15 will be added to the side of the ball screw device 12 near the motor 11 so that the angular ball bearings 15 are screws. The fixed end of the shaft 121, however, in order to fix the angular ball bearing 15, an additional set of fixing nuts 16 corresponding to the angular ball bearing 15 must be added, so that the motor 11 cannot be directly connected to the ball screw device 12, further As a result, the assembly space of the linear drive system 1 becomes larger.

Therefore, how to develop a linear drive system that can improve the lack of the conventional technology is a problem that needs to be solved by those skilled in the related art.

The purpose of this case is to provide a linear drive system. To solve the conventional linear drive system, it is necessary to add a set of couplings and fixed nuts with fixed angular ball bearings, which leads to a decrease in overall rigidity, an increase in cost, and a large lack of assembly space. .

Another purpose of this case is to provide a linear drive system that uses a screw to directly connect to the rotor without the need for additional couplings. It has the advantages of greater rigidity, fast response speed, and lower cost. Used as the screw nut, the linear drive system in this case has the advantages of less assembly space and easy disassembly and maintenance.

In order to achieve the above purpose, one of the broader implementation aspects of the present case is to provide a linear drive system including a motor, a screw, and a slide table. The motor includes a rotor, a stator, and a ball bearing. The rotor includes a rotating shaft portion and a spiral portion. The rotating shaft portion and the spiral portion have a receiving space connected to each other. The inner surface of the spiral portion has a first thread. The screw system is coaxially arranged with the rotor, and the outer surface of one end of the screw is provided with a second thread, and is at least partially accommodated in the accommodation space of the rotor. The slide table is fixed at the other end of the screw, wherein the first thread of the helical part of the rotor is engaged with the second thread of the screw, and the rotor rotates to drive the screw and the slide table connected to the screw is parallel to the axial direction of the rotor Linear reciprocating movement in the direction of.

Some typical embodiments embodying the features and advantages of this case will be described in detail in the description in the subsequent paragraphs. It should be understood that the present case can have various changes in different aspects, all of which do not depart from the scope of the present case, and that the descriptions and diagrams therein are essentially for the purpose of illustration, rather than limiting the case.

Please refer to FIG. 2 and FIG. 3, wherein FIG. 2 is a schematic cross-sectional structure diagram of the linear driving system according to the first preferred embodiment of the present invention, and FIG. 3 is a part of the components of the linear driving system shown in FIG. Sectional structure diagram. As shown in the figure, the linear drive system 2 of the present case includes a motor 21, a screw 22, and a slide table 23. The motor 21 may be, but is not limited to, a servo motor. The motor 21 includes a rotor 211, a stator 212, and a ball bearing 213. The rotor 211 includes a rotating shaft portion 214 and a spiral portion 215. The rotating shaft portion 214 and the spiral portion 215 are connected to each other. The rotating shaft portion 214 and the spiral portion 215 have a receiving space 216 communicating therewith. A hollow space is formed in the spiral portion 215, and an inner surface of the spiral portion 215 has a first thread 2151.

In the above embodiment, the rotor 211 may further include a plurality of permanent magnets 217, and the plurality of permanent magnets 217 are annularly disposed outside the rotating shaft portion 214 of the rotor 211. The stator 212 is disposed outside the permanent magnet 217 of the rotor 211, and may further include a plurality of coil windings (not shown). The coil windings are used to carry a current and generate a magnetic field interaction with the plurality of permanent magnets 217 of the rotor 211. In order to generate a driving force, the rotating shaft portion 214 and the spiral portion 215 of the rotor 211 are rotated, and the first thread 2151 is further rotated correspondingly.

The ball bearing 213 of the motor 21 is provided outside the spiral portion 215 of the rotor 211 of the motor 21. When the rotor 211 receives the driving force and rotates, the ball bearing 213 is used to support the rotation of the rotor 211. It is limited to oblique ball bearings, and the ball bearings 213 can also be arranged in pairs and symmetrically outside the spiral portion 215, such as two or four, but the number of the ball bearings 213 is not limited to this.

The screw 22 is coaxially disposed with the rotor 211 of the motor 21. The screw 22 includes a first end portion 221 and a second end portion 222. The first end portion 221 is at least partially accommodated in the accommodation space 216 of the rotor 211, and The outer surface of the first end portion 221 has a second thread 2211 that can be engaged with the first thread 2151. The meshing of the first thread 2151 and the second thread 2211 is used to connect the spiral portion 215 and the screw 22 of the rotor 211 of the motor 21. The screw portion 215 is used as the nut of the screw 22, and the second threads 2211 extend evenly from one end of the first end portion 221 to the other end where the first end portion 221 and the second end portion 222 are connected. . When the rotor 211 is rotated by the driving force, the first thread 2151 of the spiral portion 215 rotates correspondingly, and the second thread 2211 meshing with the first thread 2151 is further driven to rotate, so that the screw 22 is driven in parallel by the spiral portion 215. The rotor 211 is linearly reciprocated in the axial direction.

The slide table 23 is fixedly connected to the second end portion 222 of the screw 22 and is used to carry a load (not shown). When the screw 22 linearly reciprocates in the axial direction of the parallel rotor 211, the slide table 23 connected to the screw 22 is driven by the screw 22, and also linearly reciprocates in the axial direction of the parallel rotor 211, thereby achieving The rotational movement of the motor 21 is converted into a linear movement of the slide table 23.

It can be known from the above that the first end portion 221 of the screw 22 of the linear drive system 2 of the present case is accommodated in the accommodation space 216 of the rotor 211 of the motor 21, and the first end portion 221 of the screw 22 and the rotor 211 of the motor 21 The accommodation space 216 is directly connected, and no additional device is needed to connect the screw 22 and the rotor 211 of the motor 21. Therefore, compared with the conventional linear drive system 1, an additional set of couplings 13 is required. The rigidity of the linear drive system 2 in this case Larger, faster response, and cheaper. In addition, the meshing of the first thread 2151 and the second thread 2211 of the linear drive system 2 of the present case is used to connect the screw portion 215 and the screw 22 of the rotor 211 of the motor 21, so that the screw portion 215 is used as the nut of the screw 22 Compared with the conventional linear drive system 1, a set of oblique ball bearings 15 is added as a fixed end of the screw shaft 121 on the side of the ball screw device 12 near the motor 11, and an additional set of fixed oblique ball bearings is added. 15 and the corresponding fixed nut 16, the linear drive system 2 in this case does not need to add additional angular ball bearings and fixed nuts to connect the rotor and screw of the motor, so the linear drive system 2 in this case has lower cost and assembly It has the advantages of less space and easy removal of the screw 22 for maintenance.

Please refer to FIG. 2 and FIG. 3 again. The rotating shaft portion 214 and the spiral portion 215 of the linear drive system 2 are integrally formed, and the outer surface of the spiral portion 215 has a third thread 2152 having a serrated portion structure.

In addition, the ball bearing 213 of the linear drive system 2 is provided on the outer side of the spiral portion 215, and the motor 21 of the linear drive system 2 further includes a locking element 218 provided on the outer surface of the spiral portion 215 of the rotor 211, and the lock The fixing element 218 is disposed adjacent to the ball bearing 213. The locking element 218 includes a first end 2181 and a second end 2182. The first ends 2181 are adjacent to each other and pass through the ball bearing 213, thereby locking the ball bearing 213 with the locking element 218. The inner surface of the second end 2182 has a fourth thread 2183, the fourth thread 2183 is adjacent to the outer surface of the spiral portion 215, and the fourth thread 2183 can be engaged with the third thread 2152 on the outer surface of the spiral portion 215 for engagement. The locking element 218 and the spiral portion 215. In some embodiments, the motor 21 of the linear drive system 2 further includes a supporting element 219 adjacent to the ball bearing 213 to support the ball bearing 213.

In addition, the slide table 23 further includes a slider 231, a platform 232, and a linear bearing 233. The slider 231 is connected to the second end portion 222 of the screw 22. When the screw 22 performs linear motion, the slider 231 drives the slide table 23 to perform linear motion. The platform 232 is disposed and connected above the slider 231 to carry a load (not shown), and performs linear motion through the slide table 23 to drive the load to perform linear motion. The linear bearing 233 is arranged and connected below the slider 231 to limit the linear movement of the slider 231 on the outer frame (not shown) of the linear drive system 2 without deviating from the track of the outer frame.

In the above embodiment, the motor 21 further includes a position sensor 210 such as an encoder, and the position sensor 210 is disposed at one end of the rotating shaft portion 212 of the rotor 211 to sense the rotational position of the rotor 211. In some embodiments, the screw 22 further includes a plurality of stops 223, which are disposed on the surface of the first end 221 of the screw 22. When the screw 22 performs linear movement, the stop 223 is used to prevent the screw 22 from leaving the rotor 211. .

Please refer to FIG. 4, FIG. 5A, and FIG. 5B, where FIG. 4 is a schematic cross-sectional structure diagram of the linear driving system of the second preferred embodiment of the present invention, and FIG. 5A is the linear driving system shown in FIG. A schematic cross-sectional structure of some components is shown in FIG. 5B, which is a schematic cross-sectional view of the rotor shown in FIG. 5A in the direction of AA ′. As shown in the figure, the linear drive system 4 of this embodiment includes a motor 41, a screw 42 and a slide table 43. Among them, the motor 41, the screw 42 and the slide 43 of the linear drive system 4 are respectively linearly driven as shown in FIG. The motor 21, the screw 22, and the slide table 23 of the system 2 are similar, and similar component numbers represent similar component structures, operations, and functions, so they are not repeated here. In this embodiment, the motor 41 includes a rotor 411, a stator 412, and a ball bearing 413. The rotor 411 includes a rotating shaft portion 414 and a spiral portion 415. The rotating shaft portion 414 and the spiral portion 415 are independently provided in an assembly manner, and the rotating shaft portion 414 An accommodating space 416 is communicated with the spiral portion 415, and the accommodating space 416 is a hollow space in the rotating shaft portion 414 and the spiral portion 415.

The shaft portion 414 of the rotor 411 of the motor 41 further includes a first connection portion 4141. The first connection portion 4141 is disposed on the outer circumference of one end of the shaft portion 414, and includes at least a first through hole 4142 and at least a first positioning hole. 4143, for example, as shown in FIG. 5B, there are three first through holes 4142 and first positioning holes 4143. The first through holes 4142 and the first positioning holes 4143 are alternately disposed on the outer circumference of the first connecting portion 4141. . The spiral portion 415 of the rotor 411 of the motor 41 further includes a second connection portion 4153. The second connection portion 4153 is provided on the outer circumference of one end of the spiral portion 415 adjacent to the shaft portion 414, and is disposed adjacent to the first connection portion 4141. It also includes a plurality of second through holes 4154 corresponding to the first through hole 4142 and at least one second positioning hole 4155 corresponding to the first positioning hole 4143. The first positioning hole 4143 and the second positioning hole 4155 are for the rotating shaft. The portion 414 and the spiral portion 415 are positioned with respect to each other. The rotor 411 of the motor 41 further includes at least one connecting element 4156. The connecting element 4156 is provided with a first through hole 4142 corresponding to the first connecting portion 4141 and a second through hole 4154 corresponding to the second connecting portion 4153. A through hole 4142 and a second through hole 4154 are connected, and the rotating shaft portion 414 and the spiral portion 415 are fixed, and the rotating shaft portion 414 and the spiral portion 415 are coaxially disposed. Therefore, the rotating shaft portion 414 and the spiral portion 415 in this embodiment are detachable, which facilitates maintenance and replacement of the rotor 411.

In the above-mentioned embodiment, the ball bearing 413 of the linear drive system 4 is annularly disposed outside the spiral portion 415, and the motor 41 of the linear drive system 4 further includes a locking element 418 disposed outside the spiral portion 415 of the rotor 411 Surface, and the locking element 418 is disposed adjacent to the ball bearing 413, wherein the locking element 418 includes a first end 4181 and a second end 4182. The first ends 4181 are adjacent to each other and pass through the ball bearing 413, thereby locking the ball bearing 413 with the locking element 418, and the ball bearing 413 is disposed on the outer surface of the spiral portion 415. The inner surface of the second end 4182 has a fourth thread 4183, the fourth thread 4183 is adjacent to the outer surface of the spiral portion 415, and the fourth thread 4183 can be engaged with the third thread 4152 on the outer surface of the spiral portion 415 for engagement. The locking element 418 and the spiral portion 415. In some embodiments, the motor 41 of the linear drive system 4 further includes a supporting element 419 adjacent to the ball bearing 413 to support the ball bearing 413.

When the rotor 411 of the motor 41 rotates by the driving force, the first thread 4151 of the spiral portion 415 of the motor 41 rotates correspondingly, and the second thread 4211 of the screw 42 meshing with the first thread 4151 of the spiral portion 415 of the motor 41 is further turned by Driven to rotate, the screw 42 is linearly reciprocated in the direction parallel to the axial direction of the rotor 411 by the screw portion 415. Since the first end portion 421 of the screw 42 is directly connected to the accommodation space 416 of the rotor 411 of the motor 41, no additional device is needed to connect the screw 42 and the rotor 411 of the motor 41, so the linear drive system 4 in this case has greater rigidity. It has the advantages of faster response speed and lower cost. In addition, the meshing of the first thread 4151 and the second thread 4211 of the linear drive system 4 in this case is used to connect the screw portion 415 and the screw 42 of the rotor 411 of the motor 41, so that the screw portion 415 is used as the nut of the screw 42 It is not necessary to add additional angular ball bearings and fixed nuts to connect the rotor and the screw. Therefore, the linear drive system 4 in this case has the advantages of cheaper cost, less assembly space, and easy disassembly of the screw 42 for maintenance.

Please refer to FIG. 6 and FIG. 7, where FIG. 6 is a schematic cross-sectional structure diagram of the linear driving system according to the third preferred embodiment of the present invention, and FIG. 7 is a part of the components of the linear driving system shown in FIG. 6. Sectional structure diagram. As shown in the figure, the linear drive system 6 of this embodiment includes a motor 61, a screw 62, and a slide table 63, wherein the motor 61, the screw 62, and the slide 63 of the linear drive system 6 are respectively linearly driven as shown in FIG. The motor 21, the screw 22, and the slide table 23 of the system 2 are similar, and similar component numbers represent similar component structures, operations, and functions, so they are not repeated here. In this embodiment, the motor 61 includes a rotor 611, a stator 612, and a ball bearing 613. The rotor 611 includes a rotating shaft portion 614 and a spiral portion 615. The rotating shaft portion 614 and the spiral portion 615 are independently provided in an assembly manner, and the rotating shaft portion 614 An accommodating space 616 communicating with the spiral portion 615 is provided, and the accommodating space 616 is a hollow space in the rotating shaft portion 614 and the spiral portion 615.

The rotating shaft portion 614 of the rotor 611 includes a shaft portion body 6141 and a first extension portion 6142. The shaft portion body 6141 and the first extension portion 6142 are connected to each other. The inner diameter Ra of the shaft portion body 6141 is smaller than that of the first extension portion 6142. The inner diameter Rb, the inner surface of the first extension portion 6142 has a fifth thread 6143. The spiral portion 615 has a sixth thread 6152. The sixth thread 6152 is provided at least partially on the outer surface of the spiral portion 615, and is disposed corresponding to the fifth thread 6143. The sixth thread 6152 and the fifth thread 6143 can be mutually connected. After meshing, the sixth thread 6152 and the fifth thread 6143 can be used to combine and fix the rotating shaft portion 614 and the spiral portion 615, and the first extension portion 6142 is ring-shaped at least partially outside the spiral portion 615. Therefore, the rotating shaft portion 614 and the spiral portion 615 of this embodiment are detachable, which is beneficial to the maintenance and replacement of the rotor 611.

In some embodiments, the outer surface of the spiral portion 615 further includes a convex portion 6153 that is a convex structure, and a ball bearing 613 is disposed and fixed to one end of the first extension portion 6142 of the rotating shaft portion 614 and the convex portion of the spiral portion 615. The ball bearing 613 is provided between the set portions 6153 and the outer surface of the spiral portion 615. In some embodiments, the motor 61 of the linear drive system 6 further includes a supporting element 619 adjacent to the ball bearing 613 to support the ball bearing 613.

When the rotor 611 of the motor 61 is rotated by the driving force, the first thread 6151 of the spiral portion 615 of the motor 61 rotates correspondingly, and the second thread 6211 of the screw 62 meshing with the first thread 6151 of the spiral portion 615 of the motor 61 is further turned by Driven to rotate, the screw 62 is linearly reciprocated in the direction parallel to the axial direction of the rotor 611 by the screw portion 615. Since the first end portion 621 of the screw 62 is directly connected to the accommodating space 616 of the rotor 611 of the motor 61, no additional device is required to connect the screw 62 and the rotor 611 of the motor 61. Therefore, the linear drive system 6 in this case has a relatively high rigidity. It has the advantages of faster response speed and lower cost. In addition, the meshing of the first thread 6151 and the second thread 6211 of the linear drive system 6 in this case is used to connect the screw portion 615 and the screw 62 of the rotor 611 of the motor 61, so that the screw portion 615 is used as the nut of the screw 62 It does not need to add additional angular ball bearings and fixed nuts to connect the rotor and the screw. Therefore, the linear drive system 6 in this case has the advantages of lower cost, less assembly space, and easy disassembly of the screw 62 for maintenance.

Please refer to FIG. 8 and FIG. 9, wherein FIG. 8 is a schematic cross-sectional structure diagram of the linear driving system according to the fourth preferred embodiment of the present invention, and FIG. 9 is a part of the components of the linear driving system shown in FIG. 8. Sectional structure diagram. As shown in the figure, the linear drive system 8 of this embodiment includes a motor 81, a screw 82, and a slide table 83. The motor 81, the screw 82, and the slide 83 of the linear drive system 8 are respectively linearly driven as shown in FIG. 2. The motor 21, the screw 22, and the slide table 23 of the system 2 are similar, and similar component numbers represent similar component structures, operations, and functions, so they are not repeated here. In this embodiment, the motor 81 includes a rotor 811, a stator 812, and a ball bearing 813. The rotor 811 includes a rotating shaft portion 814 and a spiral portion 815. The rotating shaft portion 814 and the spiral portion 815 are independently provided in an assembly manner, and the rotating shaft portion 814 An accommodating space 816 is connected to the spiral portion 815, and the accommodating space 816 is a hollow space in the rotating shaft portion 814 and the spiral portion 815.

The rotating shaft portion 814 of the rotor 811 has a shaft portion body 8141 and a first extension portion 8142. The inner diameter Ra of the shaft portion body 8141 is smaller than the inner diameter Rb of the first extension portion 8142. The inner surface of the first extension portion 8142 has Fifth thread 8143. The spiral portion 815 of the rotor 811 has a sixth thread 8152. The sixth thread 8152 is at least partially provided on the outer surface of the spiral portion 815 and is provided corresponding to the fifth thread 8143. The fifth thread 8143 and the sixth thread 8152 The intermeshing system can be engaged with each other, and is used for assembling and fixing the rotating shaft portion 814 and the spiral portion 815, and the first extension portion 8142 is looped on at least part of the outside of the spiral portion 815.

The outer surface of the first extension portion 8142 includes a bearing surface 8144, and the outer surface of the first extension portion 8142 has a seventh thread 8145. The bearing surface 8144 is used to carry the ball bearing 813. The motor 81 of the linear drive system 8 further includes a locking element 818, which is provided on the outer surface of the first extension 8142 of the spiral portion 814 of the rotor 811, and the locking element 818 is provided adjacent to the ball bearing 813, among which the locking element 818 includes a first end 8181 and a second end 8182. The first end 8181 is adjacent to and penetrates the ball bearing 813, thereby locking the ball bearing 813 with a locking element 818. The inner surface of the second end 8182 has a fourth thread 8183, and the fourth thread 8183 is adjacent to the shaft portion. The outer surface of the first extension portion 8142 of the 814, and the fourth thread 8183 can be engaged with the seventh thread 8145 of the outer surface of the spiral portion 815, for engaging the locking element 818 and the rotating shaft portion 814.

In this embodiment, the rotating shaft portion 814 further includes a positioning portion 8146. The positioning portion 8146 is disposed inside the rotating shaft portion 814, and the positioning portion 8146 and the leading edge of the spiral portion 815 are engaged with each other for positioning, so that the spiral portion 815 and The rotating shaft portion 814 is more accurately positioned when fixedly connected.

In some embodiments, the outer surface of the spiral portion 815 further includes a convex portion 8153 which is a convex structure. When the rotating shaft portion 814 is fixedly connected to the spiral portion 815, the first extending portion 8142 and the spiral portion of the rotating shaft portion 814 are fixedly connected. The convex portion of 815 is in contact with 8153. In some embodiments, the motor 81 of the linear drive system 8 further includes a supporting element 819 adjacent to the ball bearing 813 to support the ball bearing 813.

When the rotor 811 of the motor 81 is rotated by the driving force, the first thread 8151 of the spiral portion 815 of the motor 81 rotates correspondingly, and the second thread 8211 of the screw 82 meshing with the first thread 8151 of the spiral portion 815 of the motor 81 is further turned by Driven to rotate, the screw 82 is linearly reciprocated in the direction parallel to the axial direction of the rotor 811 by the screw portion 815. Since the first end portion 821 of the screw 82 is directly connected to the accommodation space 816 of the rotor 811 of the motor 81, no additional device is needed to connect the screw 82 and the rotor 811 of the motor 81. Therefore, the linear drive system 8 of this case has a relatively high rigidity. It has the advantages of faster response speed and lower cost. In addition, the meshing of the first thread 8151 and the second thread 8211 of the linear drive system 8 in this case is used to connect the screw portion 815 and the screw 82 of the rotor 811 of the motor 81, so that the screw portion 815 is used as the nut of the screw 82 It does not need to add additional angular ball bearings and fixed nuts to connect the rotor and the screw. Therefore, the linear drive system 8 in this case has the advantages of lower cost, less assembly space, and easy disassembly of the screw 82 for maintenance.

In summary, this case provides a linear drive system. The first end of the screw of the linear drive system is accommodated in the accommodation space of the rotor of the motor. The rotor and the motor are directly connected, so compared with the conventional linear system, The drive system requires an additional set of couplings. The linear drive system in this case has greater rigidity, faster response speed, and lower cost. In addition, the engagement of the first thread and the second thread of the linear drive system in this case is used to connect the screw portion and the screw of the rotor of the motor, so that the screw portion is used as the nut of the screw, so compared with the conventional linear The drive system adds a set of angled ball bearings as the fixed end of the screw shaft on the side of the ball screw near the motor, and an additional set of fixed nuts corresponding to the angled ball bearings. The linear drive system in this case is not An additional angular ball bearing and a fixed nut are needed to connect the rotor and the screw. Therefore, the linear drive system in this case has the advantages of lower cost, less assembly space, and easy disassembly of the screw for maintenance.

1, 2, 4, 6, 8‧‧‧ linear drive systems

11, 21, 41, 61, 81‧‧‧ Motor

210, 410, 610, 810‧‧‧ position sensors

111, 211, 411, 611, 811‧‧‧ rotor

112, 212, 412, 612, 812‧‧‧ stator

113‧‧‧Motor shaft

114‧‧‧ permanent magnet

12‧‧‧ball screw device

121‧‧‧Screw shaft

122‧‧‧Slide nut

123‧‧‧Slide

124‧‧‧ Linear Bearing

125‧‧‧ support bearing

13‧‧‧Couplings

14‧‧‧Frame

15‧‧‧bearing

16‧‧‧ fixed nut

213, 413, 613, 813‧‧‧ ball bearings

214, 414, 614, 814‧‧‧‧ shaft section

4141‧‧‧First connection

4142‧‧‧First through hole

4143‧‧‧First positioning hole

6141, 8141‧‧‧Shaft body

6142, 8142‧‧‧ First extension

6143, 8143‧‧‧ fifth thread

8144‧‧‧bearing surface

8145‧‧‧ seventh thread

8146‧‧‧Positioning Department

215, 415, 615, 815‧‧‧ spiral

2151, 4151, 6151, 8151‧‧‧ first thread

2152, 4152‧‧‧ Third thread

8152‧‧‧ Sixth thread

4153‧‧‧Second connection

4154‧‧‧Second through hole

4155‧‧‧Second positioning hole

4156‧‧‧Connecting element

6152‧‧‧ Sixth thread

6153, 8153 ‧‧‧ convex

216, 416, 616, 816‧‧‧ accommodation space

217, 417, 617, 817‧‧‧ permanent magnets

218, 418, 818‧‧‧Locking elements

2181, 4181, 8181‧‧‧ first end

2182, 4182, 8182‧‧‧ second end

2183, 4183, 8183‧‧‧ Fourth thread

219, 419, 619, 819‧‧‧ support elements

22, 42, 62, 82‧‧‧ screw

221, 421, 621, 821‧‧‧ first end

2211, 4211, 6211, 8211‧‧‧ second thread

222, 422, 622, 822‧‧‧ second end

223, 423, 623, 823‧‧‧ stop

23, 43, 63, 83‧‧‧Slide tables

231, 431, 631, 831‧‧‧ slider

232, 432, 632, 832‧‧‧ platforms

233, 433, 633, 833‧‧‧ linear bearings

Ra, Rb‧‧‧Inner diameter

Figure 1 is a schematic cross-sectional structure diagram of a conventional linear drive system. FIG. 2 is a schematic cross-sectional structure diagram of the linear driving system of the first preferred embodiment of the present invention. FIG. 3 is a schematic cross-sectional structure diagram of some components of the linear drive system shown in FIG. 2. FIG. 4 is a schematic cross-sectional structure diagram of a linear driving system according to a second preferred embodiment of the present invention. FIG. 5A is a schematic cross-sectional structure diagram of some components of the linear drive system shown in FIG. 4. Fig. 5B is a schematic cross-sectional view of the rotor shown in Fig. 5A in the direction of A-A '. FIG. 6 is a schematic cross-sectional structure diagram of a linear driving system according to a third preferred embodiment of the present invention. FIG. 7 is a schematic cross-sectional structure diagram of some components of the linear drive system shown in FIG. 6. FIG. 8 is a schematic cross-sectional structure diagram of a linear driving system according to a fourth preferred embodiment of the present invention. FIG. 9 is a schematic cross-sectional structure diagram of some components of the linear drive system shown in FIG. 8.

Claims (15)

A linear drive system includes: a motor including a rotor, a stator, and a ball bearing, wherein the rotor includes a rotating shaft portion and a spiral portion, and the rotating shaft portion and the spiral portion have an accommodating space connected with each other, The inner surface of the spiral portion has a first thread; a screw is disposed coaxially with the rotor; an outer surface of one end of the screw has a second thread, and is at least partially accommodated in the capacity of the rotor. And a sliding table, which is fixed at the other end of the screw, wherein the first thread of the spiral portion of the rotor is engaged with the second thread of the screw, and the rotor rotates to drive the screw The screw and the slide table connected to the screw are linearly reciprocated in a direction parallel to the axial direction of the rotor. The linear drive system according to claim 1, wherein the ball bearing ring is provided outside the spiral portion to support the rotor. The linear drive system according to claim 1, wherein the outer surface of the spiral portion has a third thread. The linear drive system according to claim 3, wherein the motor further includes a locking element, the locking element includes a first end and a second end, and the first end is threaded through the ball bearing, and the first The inner surface of the two ends has a fourth thread, wherein the third thread is engaged with the fourth thread, so that the second end engages the locking element and the spiral portion. The linear drive system according to claim 1, wherein the rotating shaft portion and the spiral portion of the rotor are integrally formed. The linear drive system according to claim 1, wherein the rotating shaft portion and the spiral portion of the rotor are independently arranged in an assembly manner. The linear drive system according to claim 6, wherein the ball bearing ring is provided outside the spiral portion to support the rotor. The linear drive system according to claim 6, wherein the shaft portion includes a first through hole, and the spiral portion includes a second through hole corresponding to the first through hole, wherein the shaft portion and the spiral portion are connected by A connecting element is fixed through the first through hole and the second through hole. The linear drive system according to claim 6, wherein the rotating shaft portion includes a first positioning hole, and the spiral portion includes a second positioning hole corresponding to the first positioning hole, wherein the first positioning hole and the second positioning hole The holes are used for positioning the rotating shaft part and the spiral part with each other. The linear drive system according to claim 6, wherein the rotating shaft portion has a shaft portion body and a first extension portion, and an inner diameter of the shaft portion body is smaller than an inner diameter of the first extension portion. The linear drive system according to claim 10, wherein an inner surface of the first extension portion has a fifth thread, and an outer surface of the spiral portion has a sixth thread, wherein the fifth thread and the sixth thread Engage to fix the rotating shaft portion and the spiral portion in combination. The linear drive system according to claim 10, wherein the spiral portion has a convex portion, and the ball bearing is disposed and fixed between the first extension portion of the rotating shaft portion and the convex portion of the spiral portion. The linear drive system according to claim 10, wherein the first extension portion is disposed between the ball bearing and the spiral portion. The linear drive system according to claim 10, wherein an outer surface of the first extension includes a bearing surface, the ball bearing is disposed on the bearing surface, and an outer surface of the first extension has a seventh thread, A locking element is provided for engaging the ball bearing and the rotating shaft portion. The linear drive system according to claim 10, wherein the shaft portion further includes a positioning portion, and the positioning portion is engaged with the leading edge of the spiral portion for positioning.