An additively manufactured flexible harmonic reducer nuclear magnetic compatible pneumatic motor

Abstract

The invention discloses an additively manufactured flexible harmonic reducer nuclear magnetic compatible pneumatic motor, comprising a shell, a thin plate, a photoelectric encoder, a wave generator, a rigid wheel, a flexible wheel and an external bearing; the shell is connected to the thin plate; the shell is provided with an air inlet, a light inlet and an inner cavity which is conductive with the air inlet and the light inlet; the thin plate is provided with a through hole; the photoelectric encoder comprises a main body and a connecting rod inserted through the main body, the main body is placed in the inner cavity, one end of the connecting rod passes through the light inlet and is connected to the thin plate, the other end of the connecting rod passes through the through hole and is connected to one end of the wave generator, and the other end of the wave generator is connected to bearing three; the rigid wheel is provided with an enclosure frame, the enclosure frame encloses the wave generator and is connected to the thin plate; the flexible wheel is meshedly connected to the rigid wheel, the wave generator and bearing three are embedded in the flexible wheel; the external bearing is connected to the flexible wheel; after the above motor is adopted, gas is input from the air inlet to drive the motor with gas, light enters from the light inlet, the photoelectric editor measures the rotation speed by outputting an electrical signal, so that the flexible wheel can quantitatively adjust the movement speed.

Description

Technical Field

[0001] The present invention relates to the field of motors, and in particular to an additively manufactured flexible harmonic reducer nuclear magnetic compatible pneumatic motor. Background Art

[0002] Magnetic resonance imaging (MRI) is a non-invasive, radiation-free soft tissue imaging technique. MRI can avoid exposing patients or operators to ionizing radiation, and the imaging results are better than other imaging methods, so it is often used in surgical operations.

[0003] Puncture surgery is a common minimally invasive surgical procedure in clinical practice. Under the guidance of medical images, doctors need to insert a puncture needle through the skin to the lesion area to establish a channel for biopsy or interventional treatment. In order to improve surgical accuracy and reduce the trauma caused by surgery to patients, robots are often used to assist doctors in performing surgery under the guidance of magnetic resonance imaging.

[0004] To ensure that the puncture surgical robot works normally in the high-intensity magnetic field of the MRI machine, it is necessary to ensure that the puncture surgical robot does not interfere with the MRI imaging, and the puncture robot needs to have MRI compatibility. Therefore, this type of puncture surgical robot cannot use traditional motors as drivers. Currently, the feasible driving methods mainly include hydraulic drive, pneumatic drive, and ultrasonic / piezoelectric drive. Among them, pneumatic drive has the advantages of good MRI compatibility, high power and mass ratio, clean, simple structure, and easy maintenance. It is a more ideal driving method. At the same time, in order to provide the robot with rotational motion, it is necessary to choose a good pneumatic motor.

[0005] Harmonic reducers are precision reducers used in the joints of industrial robots. They are usually composed of three major components: a flexible wheel, a rigid wheel, and a wave generator. Harmonic reducers use the rotation of the wave generator to cause the flexible wheel to produce periodic wave deformation, forcing the flexible wheel and the rigid wheel to mesh with each other with a small tooth difference, thereby realizing the transmission of motion. Harmonic reducers are used to adjust the speed of movement and output torque. Because of their large transmission ratio, they are widely used in the field of mechanical transmission, especially in the field of medical equipment. In addition, medical equipment is expected to be quickly manufactured and easy to install and use due to the special nature of its use. Therefore, there is a great practical need to apply harmonic reducer nuclear magnetic compatible pneumatic motors to puncture surgical robots. Summary of the invention

[0006] The purpose of the present invention is to provide an additively manufactured flexible harmonic reducer nuclear magnetic compatible pneumatic motor to solve the problems that the power device of the existing puncture surgical robot cannot achieve nuclear magnetic compatibility and adjust the movement speed.

[0007] In order to solve the above technical problems, the present invention provides an additively manufactured flexible harmonic reducer nuclear magnetic compatible pneumatic motor, including a shell, a thin plate, a photoelectric encoder, a wave generator, a rigid wheel, a flexible wheel and an external bearing; the shell is connected to the thin plate; the shell is provided with an air inlet, a light inlet and an inner cavity, the air inlet and the light inlet are both connected to the inner cavity, and a bearing 1 is connected to the inner cavity; the thin plate is provided with a through hole, and a bearing 2 is inserted through the through hole; the photoelectric encoder includes a main body and a connecting rod inserted into the main body, the main body is placed in the inner cavity, one end of the connecting rod is inserted and connected with the bearing 1 and then passes through the Light inlet, the other end of the connecting rod passes through the bearing two and is connected to one end of the wave generator, and the other end of the wave generator is connected to the bearing three; the outer peripheral side of the rigid wheel is provided with an enclosure frame, the enclosure frame is connected to the thin plate, and the enclosure frame encloses the wave generator; the flexible wheel is embedded in the rigid wheel and meshed with the rigid wheel, and the wave generator and the bearing three are embedded in the flexible wheel; the external bearing is connected to the flexible wheel; the air inlet is used to input gas, the gas drives the photoelectric encoder to rotate, drives the wave generator to rotate, and then transmits the speed to the flexible wheel for deceleration to achieve the driving effect.

[0008] In one of the embodiments, light source mounting positions are provided on both sides of the light inlet, and the light source mounting positions are used to install the light source device.

[0009] In one of the embodiments, one end of the connecting rod that is interlaced with the bearing has a notch, the notch is axially aligned with the light inlet, and the notch radially penetrates the connecting rod.

[0010] In one of the embodiments, mounting holes 1 are provided at both ends of the wave generator, bolts are installed in the mounting holes 1, and the bolts are embedded in the flexible wheel.

[0011] In one embodiment, the number of teeth of the rigid wheel is two more than the number of teeth of the flexible wheel.

[0012] In one of the embodiments, the shell, the thin plate and the rigid wheel are each provided with a plurality of mounting holes 2, and the plurality of mounting holes 2 are used for installing bolts connecting the shell, the thin plate and the rigid wheel.

[0013] In one embodiment, the shell, the thin plate, the photoelectric encoder, the wave generator, the rigid wheel, the flexible wheel and the external bearing are all made of nuclear magnetic compatible materials, including but not limited to polylactic acid.

[0014] The beneficial effects of the present invention are as follows:

[0015] The present invention provides an additively manufactured flexible harmonic reducer nuclear magnetic field compatible pneumatic motor, which combines a harmonic reducer with a pneumatic motor, so that compared with the common pneumatic motors on the market, it has the characteristics of simple structure and efficient adjustment of movement speed; at the same time, it is made of 3D printing technology materials, so that compared with traditional motor drives, it has the characteristics of nuclear magnetic field compatibility, low cost, and green environmental protection, and can be widely used in the medical field. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a structural schematic diagram of a pneumatic motor with a harmonic reducer provided by the present invention;

[0018] Figure 2 is a cross-sectional view of a pneumatic motor with a harmonic reducer provided by the present invention;

[0019] Figure 3 It is a structural schematic diagram of the housing provided by the present invention;

[0020] Figure 4 It is a structural schematic diagram of the photoelectric encoder provided by the present invention;

[0021] Figure 5 It is a schematic diagram of the structure of the thin plate provided by the present invention;

[0022] Figure 6 It is a schematic diagram of the structure of the wave generator provided by the present invention;

[0023] Figure 7 It is a structural schematic diagram of a rigid wheel provided by the present invention;

[0024] Figure 8 is a schematic structural diagram of the flexible pulley provided by the present invention;

[0025] Fig. 9 is a structural schematic diagram of a bearing three provided by the present invention;

[0026] Fig.10 It is a structural schematic diagram of the external bearing provided by the present invention;

[0027] Fig.11 It is a structural schematic diagram of the bolt provided by the present invention.

[0028] The reference numerals are as follows:

[0029] 1. Shell; 10. Air inlet; 11. Light inlet; 12. Inner cavity; 13. Bearing 1; 14. Light source installation position;

[0030] 2. thin plate; 20. through hole; 21. bearing 2;

[0031] 3. Photoelectric encoder; 30. Main body; 31. Connecting rod; 310. Notch;

[0032] 4. Wave generator; 40. Mounting hole 1;

[0033] 5. rigid wheel; 50. bearing three; 51. enclosure frame;

[0034] 6. Flexwheel;

[0035] 7. External bearing;

[0036] 8. Mounting hole 2;

[0037] 9. Bolts. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0039] The present invention provides a flexible harmonic reducer nuclear magnetic compatible pneumatic motor for additive manufacturing, and its implementation example Figures 1 to 9 As shown, it includes a shell 1, a thin plate 2, a photoelectric encoder 3, a wave generator 4, a rigid wheel 5, a flexible wheel 6 and an external bearing 7; the shell 1 is connected to the thin plate 2; the shell 1 is provided with an air inlet 10, a light inlet 11 and an inner cavity 12, the air inlet 10 and the light inlet 11 are both connected to the inner cavity 12, and a bearing 13 is connected to the inner cavity 12; the thin plate 2 is provided with a through hole 20, and a bearing 21 is inserted into the through hole 20; the photoelectric encoder 3 includes a main body 30 and a connecting rod 31 inserted into the main body 30, the main body 30 is placed in the inner cavity 12, one end of the connecting rod 31 is inserted and connected with the bearing 13 and then passes through the light inlet 11, and the connecting rod 31 is connected to the inner cavity 12. The other end of the rod 31 passes through the bearing 21 and is connected to one end of the wave generator 4, and the other end of the wave generator 4 is connected to the bearing 3 50; a containing frame 51 is provided on the outer peripheral side of the rigid wheel 5, and the containing frame 51 is connected to the thin plate 2, and the containing frame 51 surrounds the wave generator 4; the flexible wheel 6 is embedded in the rigid wheel 5 and meshed with the rigid wheel 5, and the wave generator 4 and the bearing 3 50 are embedded in the flexible wheel 6 together; the external bearing 7 is connected to the flexible wheel 6; the air inlet 10 is used to input gas, and the gas drives the photoelectric encoder 3 to rotate, drives the wave generator 4 to rotate, and then transmits the speed to the flexible wheel 6 for deceleration, so as to achieve the driving effect.

[0040] After adopting the above-mentioned setting method, the wave generator 4, the rigid wheel 5 and the flexible wheel 6 form a harmonic reducer. The harmonic reducer can use simple parts to obtain a high reduction ratio, and has the advantages of high precision, high efficiency, low noise, etc. The shell 1 of the device is provided with an air inlet 10, which is a gas-driven pneumatic motor with good nuclear magnetic compatibility. The harmonic reducer is combined with the pneumatic motor, the structural design is simple, the movement speed can be adjusted, it has the advantages of good nuclear magnetic compatibility, low cost, and green environmental protection, and is widely used in the medical field.

[0041] like Figure 1 and Figure 3 As shown, light source mounting positions 14 are provided on both sides of the light inlet 11, and the light source mounting positions 14 are used to install the light source device. The light generated by the light source device enters the inner cavity 12 from the light inlet 11, and the photoelectric encoder 3 converts the entering light information into electrical information.

[0042] After adopting the above arrangement, the light source can enter the photoelectric encoder 3 from the light inlet 11, and the photoelectric encoder 3 converts the entering light information into electrical information, thereby measuring the rotation speed of the pneumatic motor.

[0043] like Figure 1 , Figure 3 to Figure 4 As shown, one end of the connecting rod 31 which is inserted and connected with the bearing 13 has a notch 310, the notch 310 is aligned with the light inlet 11 in the axial direction, and the notch 310 passes through the connecting rod 31 in the radial direction.

[0044] After adopting the above-mentioned setting method, the photoelectric encoder 3 can convert optical information into electrical information output by rotation, and its specific implementation method is: when the end of the connecting rod 31 with the slot 310 is rotated to the slot 310 and the two light source installation positions 14 are in a conducting state, the slot 310 allows the light emitted by the light source device to enter the inner cavity 12 through the light inlet 11, and outputs a high level; when the end of the connecting rod 31 with the slot 310 is rotated to the slot 310 and the two light source installation positions 14 are in a blocking state, the slot 310 blocks the light emitted by the light source device from entering the inner cavity 12 through the light inlet 11, and outputs a low level; when the level completes 4 changes, the photoelectric encoder 3 completes one rotation, and the electrical information output converted from optical information can be used to measure the rotation speed of the pneumatic motor, and the movement speed of the pneumatic motor can be quantitatively adjusted by measuring the rotation speed of the pneumatic motor.

[0045] like Figure 1 , Figures 6 to 8 , Fig.11 As shown, both ends of the wave generator 4 are provided with mounting holes 40, and bolts 9 are installed in the mounting holes 40. The bolts 9 are embedded in the flexible wheel 6, and the bolts 9 are used to promote the deformation of the flexible wheel 6.

[0046] After adopting the above-mentioned setting mode, the flexible wheel 6 is a thin shell-shaped element with elasticity. Therefore, the flexible wheel 6 can be elastically deformed under the action of the wave generator 4. The wave generator 4 is embedded in the flexible wheel 6. When the wave generator 4 rotates, the flexible wheel 6 changes from the original circle to an ellipse, while the shape of the rigid wheel 5 remains basically fixed. Therefore, a part of the deformed elliptical flexible wheel 6 is completely meshed with the rigid wheel 5, and a part is in a completely disengaged state with the rigid wheel 5; that is, the gear teeth of the elliptical flexible wheel 6 near the two ends of the long axis are completely meshed with the gear teeth of the rigid wheel 5, while the gear teeth of the elliptical flexible wheel 6 near the two ends of the short axis are completely disengaged from the rigid wheel, and the remaining gear teeth of the elliptical flexible wheel 6 are in a transitional state of meshing and disengagement; the rotation of the wave generator 4 will drive the flexible wheel 6 to continuously change its shape, so that the meshing state of the flexible wheel 6 and the rigid wheel 5 is also continuously changed, from meshing in, meshing, meshing out, disengaging, and then meshing in, and repeating over and over again, thereby realizing the transmission of motion.

[0047] like Figure 1 to Figure 2 , Figures 7 and 8 As shown, the number of teeth of the rigid wheel 5 is two more than the number of teeth of the flexible wheel 6.

[0048] After adopting the above setting mode, during the transmission process, the wave generator 4 rotates one circle, and the number of cycles of deformation of a certain point on the flexible wheel 6 is called the wave number, that is, the difference in the number of teeth of the rigid wheel 5 and the flexible wheel 6, represented by n. Commonly used transmission forms include double-wave transmission and three-wave transmission. The flexible wheel 6 of the double-wave transmission has a small stress, a relatively simple structure, and is easy to obtain a large transmission ratio, which is also the transmission mode adopted by the present invention. The flexible wheel 6 designed by the present invention has 68 teeth, and the rigid wheel 5 has 70 teeth. When the wave generator 4 rotates 360 degrees, because the number of teeth of the flexible wheel 6 is two less than the number of teeth of the rigid wheel 5, two teeth are moved counterclockwise, and then the reduction ratio, that is, the difference in the number of teeth / the number of flexible wheels, can be obtained as (68-70) / 68, which is an appropriate reduction transmission ratio.

[0049] like Figure 1 to Figure 2 , Figure 5 As shown, the housing 1 , the thin plate 2 and the enclosure frame 51 of the rigid wheel 5 are all provided with a plurality of mounting holes 8 , and the plurality of mounting holes 8 are used to install bolts 9 to connect the housing 1 , the thin plate 2 and the enclosure frame 51 .

[0050] After adopting the above arrangement, the stability of the housing 1, the thin plate 2 and the rigid wheel 5 is enhanced by connection through the bolts 9.

[0051] like Figure 1 to Figure 2 , Fig.10 As shown, the housing 1, the thin plate 2, the photoelectric encoder 3, the wave generator 4, the rigid wheel 5, the flexible wheel 6 and the external bearing 7 are all made of nuclear magnetic compatible materials.

[0052] After adopting the above setting method, the flexible harmonic reducer nuclear magnetic compatible pneumatic motor all adopts nuclear magnetic compatible materials, which has the advantages of high strength, low friction, no reduction in image quality, and low production cost. Among them, the shell 1, the thin plate 2, the photoelectric encoder 3, the wave generator 4, the rigid wheel 5, the bearing 1 13, the bearing 2 21, and the external bearing 7 are all made by 3D printing, and the materials used are common materials for 3D printing, including but not limited to PLA materials. PLA materials are polylactic acid, which is a new type of biodegradable material with good mechanical properties, physical properties, compatibility and degradability, and low price. Therefore, polylactic acid is better; the material used for the flexible wheel 6 is an elastic material, including but not limited to TPU materials. TPU materials are thermoplastic polyurethane elastomers, which are a type of elastomer that can be plasticized by heating and dissolved by solvents. It has excellent comprehensive properties of high strength, high toughness, wear resistance, and oil resistance. Its processing performance is excellent and is widely used in medical and other industries; the material used for the bearing 1 13, the bearing 2 21, and the ball in the external bearing 7 is a resin material. Resin is a polymer compound. Artificial synthetic resin has good properties and is often used in artificial industries.

[0053] The above are preferred embodiments of the present invention. It should be noted that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. An additively manufactured flexible harmonic reducer nuclear magnetic compatible pneumatic motor, characterized in that: It includes a housing, a thin plate, a photoelectric encoder, a wave generator, a rigid wheel, a flexible wheel and an external bearing; The shell is connected to the thin plate; The housing is provided with an air inlet, a light inlet and an inner cavity, the air inlet and the light inlet are both connected to the inner cavity, and a bearing 1 is connected to the inner cavity; The thin plate is provided with a through hole, and the through hole is interspersed with a second bearing; The photoelectric encoder comprises a main body and a connecting rod inserted into the main body, the main body is placed in the inner cavity, one end of the connecting rod is inserted and connected with the bearing 1 and then passes through the light inlet, the other end of the connecting rod passes through the bearing 2 and is connected to one end of the wave generator, and the other end of the wave generator is connected to the bearing 3; The outer peripheral side of the rigid wheel is provided with an enclosure frame, the enclosure frame is connected to the thin plate, and the enclosure frame encloses the wave generator; The flexible wheel is embedded in the rigid wheel and meshedly connected with the rigid wheel, and the wave generator and the bearing are embedded in the flexible wheel; The external bearing is connected to the flexible wheel; Light source installation positions are provided on both sides of the light inlet, and the light source installation positions are used to install the light source device; One end of the connecting rod that is interlaced with the bearing has a notch, the notch is aligned with the light inlet in the axial direction, and the notch radially penetrates the connecting rod; Two ends of the wave generator are provided with mounting holes one, the mounting holes one are installed with bolts, and the bolts are embedded in the flexible wheel.

2. The additively manufactured flexible harmonic reducer nuclear magnetic compatible pneumatic motor according to claim 1, characterized in that: The number of teeth of the rigid wheel is two more than the number of teeth of the flexible wheel.

3. The additively manufactured flexible harmonic reducer nuclear magnetic compatible pneumatic motor according to claim 1, characterized in that: The shell, the thin plate and the rigid wheel are all provided with a plurality of mounting holes 2, and the plurality of mounting holes 2 are used for installing bolts connecting the shell, the thin plate and the rigid wheel.

4. The additively manufactured flexible harmonic reducer nuclear magnetic compatible pneumatic motor according to claim 1, characterized in that: The shell, the thin plate, the photoelectric encoder, the wave generator, the rigid wheel, the flexible wheel and the external bearing are all made of polylactic acid.

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