Axial and circumferential movement driving device and driving method thereof

Abstract

The application discloses an axial and circumferential motion driving device and a driving method thereof. The driving device comprises a cover, a shell, a telescopic driving steering engine, a rotary driving steering engine, an output shaft, a dual-purpose cylindrical gear, a circumferential transmission gear and an axial transmission gear. The output shaft and the shell form a cylindrical pair. The circumferential transmission gear and the axial transmission gear are rotationally connected in the shell. The dual-purpose cylindrical gear is fixed on the output shaft. A plurality of gear tooth rows which are uniformly distributed along the circumferences of the dual-purpose cylindrical gear are arranged on the dual-purpose cylindrical gear. Each gear tooth row comprises a plurality of dual-purpose gear teeth which are arranged in an equal interval along the axial direction of the dual-purpose cylindrical gear. The application provides a dual-purpose cylindrical gear which can engage with two transmission gears which are perpendicular to each other. The dual-purpose cylindrical gear has the characteristics of a cylindrical gear and a rack gear, and can perform telescopic motion and rotary motion under the driving of the two transmission gears which are perpendicular to each other, so that the compactness of a two-degree-of-freedom power element is improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of steering engine design, and particularly relates to an axial and circumferential motion driving device and a driving method thereof. BACKGROUND

[0002] The conventional steering engine can only drive the rotation of the central shaft, and cannot simultaneously drive the axial movement and circumferential rotation of the central shaft. This makes the steering engine in some special occasions (for example, occasions requiring simultaneous output of circumferential rotation and axial movement) have to be matched with other moving driving mechanisms to complete the use requirements of double outputs. In the prior art, the following three structures are commonly used to realize the axial and circumferential double driving:

[0003] The first double driving structure: the steering engine and the steering engine are matched with each other to drive, one of which provides rotation, and the other is matched with a lead screw to convert the rotation into linear motion. The second double driving structure: the steering engine and the hydraulic slide are matched, in which the steering engine and the hydraulic slide drive the circumferential rotation and the axial movement respectively. The third double driving structure: the combination of two motors is used to realize it, a linear motor and a rotary motor are used to realize it.

[0004] The first and second double driving structures both need to occupy a large space, and the control is complex, and the installation cost is relatively high. The third double driving structure requires the rotary motor to be embedded in the linear motor, and the disadvantage of this layout is that it is difficult to seal and occupies a large space.

[0005] In addition, there is a linear-rotary permanent magnet actuator in the prior art, which is internally provided with a composite inner and outer double stator for driving the permanent magnet array to move in two degrees of freedom of linear and rotation. However, the actuator has a special structure, complex control, high cost, and is difficult to be serialized and marketed. SUMMARY

[0006] The purpose of the present application is to provide an axial and circumferential motion driving device and a driving method thereof.

[0007] An axial and circumferential motion driving device, comprising a cover, a shell, a telescopic driving steering engine, a rotary driving steering engine, an output shaft, a dual-purpose column gear, a circumferential transmission gear and an axial transmission gear. The output shaft and the shell form a cylindrical pair. The circumferential transmission gear and the axial transmission gear are both rotationally connected in the shell. The axis of the circumferential transmission gear is parallel to the axis of the output shaft. The axis of the axial transmission gear is perpendicular to the axis of the output shaft. The telescopic driving steering engine and the rotary driving steering engine are both fixed on the shell, and are respectively used to drive the axial transmission gear and the circumferential transmission gear.

[0008] The dual-purpose cylindrical gear is coaxially fixed on the output shaft. The outer circumferential surface of the dual-purpose cylindrical gear is provided with a plurality of rows of teeth which are uniformly distributed along the circumferential direction of the cylindrical gear axis. Each row of teeth comprises a plurality of dual-purpose teeth which are arranged in equal intervals along the axial direction of the dual-purpose cylindrical gear.

[0009] The dual-purpose teeth arranged in sequence along the axial direction of the dual-purpose cylindrical gear are in the form of a rack and can be engaged with the axial transmission gear; the dual-purpose teeth arranged in sequence along the circumferential direction of the dual-purpose cylindrical gear are in the form of a cylindrical gear and can be engaged with the axial transmission gear; during operation, the circumferential transmission gear rotates to drive the dual-purpose cylindrical gear to rotate; the axial transmission gear rotates to drive the dual-purpose cylindrical gear to move axially.

[0010] As a preferred embodiment, the two side surfaces of each dual-purpose tooth along the tangential direction of the dual-purpose cylindrical gear are circumferential engagement tooth surfaces; the circumferential engagement tooth surfaces are specifically involute tooth surfaces of a cylindrical spur gear and are engaged with the tooth surfaces on the circumferential transmission gear.

[0011] As a preferred embodiment, the two side surfaces of each dual-purpose tooth along the axial direction of the dual-purpose cylindrical gear are axial engagement tooth surfaces; the axial engagement tooth surfaces are specifically involute tooth surfaces of a straight rack and are engaged with the tooth surfaces on the axial transmission gear.

[0012] As a preferred embodiment, an axial driving gear is fixed on the rotating shaft of the telescopic drive steering gear; the axial driving gear is engaged with the axial transmission gear.

[0013] As a preferred embodiment, a circumferential driving gear is fixed on the rotating shaft of the rotary drive steering gear; the circumferential driving gear is engaged with the circumferential transmission gear.

[0014] As a preferred embodiment, the tooth top surface of the dual-purpose tooth is a partial cylindrical surface; the axis of the partial cylindrical surface coincides with the axis of the output shaft.

[0015] As a preferred embodiment, the tooth width B9 of the circumferential transmission gear is in the range of m 7' *4≤B9≤m 7' *6; the tooth width B 11 of the axial transmission gear is in the range of m7*3≤B 11 ≤m7*5. m 7' and m7 are the axial module and the circumferential module of the dual-purpose cylindrical gear.

[0016] As a preferred embodiment, the dual-purpose cylindrical gear is obtained by the following method: using a disc-shaped milling cutter or a finger-shaped milling cutter to process a cylindrical tooth blank into a dual-purpose cylindrical tooth blank in the form of a cylindrical spur gear; using a hob to process the dual-purpose cylindrical tooth blank; during the processing, the hob rotates and feeds along the radial direction of the dual-purpose cylindrical tooth blank, while the dual-purpose cylindrical tooth blank rotates around its own axis, so as to divide the tooth profile on the dual-purpose cylindrical tooth blank into an array of dual-purpose teeth which are uniformly arranged on the outer circumferential surface of the dual-purpose cylindrical gear.

[0017] As preferred, a cover is detachably fixed at the opening of the end of the shell. The outer end of the output shaft extends out of the cover.

[0018] As preferred, the output shaft is connected with the shell through a shaft sleeve.

[0019] As preferred, a plurality of balls are uniformly installed on the inner side of the shaft sleeve. The balls and the shaft sleeve form a spherical pair.

[0020] As preferred, the circumferential transmission gear is an internal gear, and the outer circumferential surface thereof is coaxially connected with the shell through a bearing. The output shaft is eccentrically arranged in the shell.

[0021] The driving method of the axial and circumferential motion driving device is as follows:

[0022] When the output shaft of the axial and circumferential motion driving device needs to perform telescopic motion, the telescopic driving rudder is rotated to drive the axial transmission gear to rotate, and then drive the output shaft and the dual-purpose cylindrical gear to slide along the axial direction.

[0023] When the output shaft of the axial and circumferential motion driving device needs to perform rotational motion, the rotational driving rudder is rotated to drive the circumferential transmission gear to rotate, and then drive the output shaft and the dual-purpose cylindrical gear to rotate around the axial line thereof.

[0024] The specific beneficial effects of the present application are as follows:

[0025] 1. The present application provides a dual-purpose cylindrical gear capable of engaging with two transmission gears perpendicular to each other. The dual-purpose cylindrical gear has the characteristics of both cylindrical gear and rack, and can perform telescopic motion and rotational motion under the driving of the two transmission gears perpendicular to each other, thereby improving the compactness of the two-degree-of-freedom power element.

[0026] 2. The present application provides a processing method of the dual-purpose cylindrical gear, which specifically processes a cylindrical workpiece into a cylindrical gear, and then processes the cylindrical gear into a rack along the axial direction. The dual-purpose cylindrical gear can be obtained by using conventional gear processing equipment, and the production cost is low. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the present application;

[0028] Figure 2 It is an exploded view of the present application;

[0029] Figure 3 It is a transmission schematic diagram of the dual-purpose cylindrical gear, the circumferential transmission gear and the circumferential driving gear in the present application;

[0030] Figure 4 It is a transmission schematic diagram of the dual-purpose cylindrical gear, the axial transmission gear and the axial driving gear in the present application;

[0031] Figure 5 Figure 2 is a partial view of the dual-purpose cylindrical gear in the application. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the application clearer, the technical solutions in the embodiments of the application will be described clearly below with reference to the drawings in the embodiments of the application.

[0033] As shown in Figure 1 and 2 , an axial and circumferential motion driving device includes a cover 1, a shell 2, an extension driving steering engine 3, a rotation driving steering engine 4, a shaft sleeve 5, an output shaft 6, a dual-purpose cylindrical gear 7, a bearing 8, a circumferential transmission gear 9, a circumferential driving gear 10, an axial transmission gear 11 and an axial driving gear 12. The output shaft 6 is eccentrically arranged in the shell 2; the two ends of the output shaft 6 are connected with the cover 1 and the shell 2 respectively through the shaft sleeve 5, and form a cylindrical pair, so that the output shaft 6 can rotate and axially slide relative to the shell 2. The inner side surface of the shaft sleeve 5 is uniformly provided with a plurality of balls to reduce the resistance of the output shaft 6 rotating and axially sliding.

[0034] As shown in Figure 3 and 4 , the cover 1 is fixed at the opening of one end of the shell 2. The circumferential transmission gear 9 is an internal gear, and its outer circumferential surface is coaxially and rotatably connected in the shell 2 through the bearing 8. The axis of the circumferential transmission gear 9 is parallel to the axis of the output shaft 6. The axial transmission gear 11 is rotatably connected in the shell 2. The axis of the axial transmission gear 11 is perpendicular to the axis of the output shaft 6. The extension driving steering engine 3 and the rotation driving steering engine 4 are both fixed in the shell 2; the output shaft 6 of the extension driving steering engine 3 is fixed with the axial driving gear 12; the output shaft 6 of the rotation driving steering engine 4 is fixed with the circumferential driving gear 10. The circumferential driving gear 10 is engaged with the circumferential transmission gear 9. The axial driving gear 12 is engaged with the axial transmission gear 11.

[0035] The dual-purpose cylindrical gear 7 is coaxially fixed on the output shaft 6. The cross section of the dual-purpose cylindrical gear 7 is in the shape of a cylindrical gear, and the longitudinal section (i.e. the axial section) is in the shape of a rack. Specifically, the outer circumferential surface of the dual-purpose cylindrical gear 7 is provided with a plurality of rows of teeth which are uniformly distributed along the circumferential direction of the cylindrical gear 7. Each row of teeth includes a plurality of dual-purpose teeth which are arranged in equal intervals along the axial direction of the dual-purpose cylindrical gear 7.

[0036] As shown in Figure 5As shown, the two sides of each dual-purpose gear tooth along the tangential direction of the dual-purpose spur gear 7 are circumferential meshing tooth surfaces 7-1; the circumferential meshing tooth surfaces 7-1 are specifically located on the involute tooth surface of the cylindrical spur gear, which can cooperate with the tooth surface on the circumferential transmission gear 9 to achieve meshing between the dual-purpose gear teeth and the circumferential transmission gear 9. The circumferential transmission gear 9 does not affect the axial sliding of the dual-purpose spur gear 7.

[0037] Each dual-purpose gear tooth has two axial meshing tooth surfaces 7-2 on its two sides along the axial direction of the dual-purpose spur gear 7. The axial meshing tooth surfaces 7-2 are specifically the involute tooth surfaces of a spur gear, which can mesh with the tooth surfaces on the axial transmission gear 11 to achieve meshing between the dual-purpose gear teeth and the axial transmission gear 11. The axial transmission gear 11 does not affect the circumferential rotation of the dual-purpose spur gear 7.

[0038] The tooth tip of the dual-purpose gear is a partially cylindrical surface; the axis of this partially cylindrical surface coincides with the axis of the output shaft.

[0039] Basic design parameters for dual-purpose spur gears: To ensure the gear's service life and strength requirements, and to prevent undercutting, the number of teeth in the design should not be less than 17, i.e., Z7 ≥ 17. To ensure the overlap ratio and the required number of teeth in the gear transmission, the minimum thickness (i.e., tooth width) of the circumferential transmission gear 9, B9 ≥ m. 7' *4; Minimum thickness (i.e., tooth width) B of axial transmission gear 11 11 ≥m7*3. m 7' m7 and m8 represent the axial and circumferential modules of the dual-purpose gears, respectively. The axial and circumferential modules can be different, and different modules can be selected according to the actual application. Therefore, the tooth width of the circumferential transmission gear 9 and the tooth width of the axial transmission gear 11 are designed according to the actual situation.

[0040] Since the tooth width of a gear determines the size of the contact area when two gears mesh, a larger contact area results in greater friction. Excessive friction is detrimental to improving transmission efficiency. Therefore, the minimum thickness (i.e., tooth width) B9 of the circumferential transmission gear 9 should be ≤ m. 7' *6; Minimum thickness (i.e., tooth width) B of axial transmission gear 11 11 ≤m7*5.

[0041] In summary: the minimum thickness (i.e., tooth width) of the circumferential transmission gear 9 is: m 7' *4≤B9≤m 7' *6; The minimum thickness (i.e., tooth width) of the axial transmission gear 11 is: m7*3≤B 11 ≤m7*5.

[0042] The specific machining process of the dual-purpose spur gear 7 is as follows:

[0043] The processing method of the dual-purpose cylindrical gear can be realized by using the traditional gear processing technology, and the main parameters of the dual-purpose cylindrical gear need to be determined before processing; firstly, according to the requirements of the output circumferential rotation speed and the axial movement speed of the bidirectional driving steering engine, in combination with the output rotation speed of the internal driving telescopic steering engine and the rotary steering engine, the circumferential tooth number and the axial tooth number of the transmission dual-purpose cylindrical gear are designed, which respectively determine the output circumferential rotation speed and the axial movement speed of the axial and circumferential movement driving device; secondly, the modulus of the dual-purpose cylindrical gear is determined according to the output power and torque of the axial and circumferential movement driving device; thirdly, the pressure angle of the gear can be generally set to 20°; and finally, the axial tooth number of the axial and circumferential movement driving device is proportional to the axial displacement output by the axial and circumferential movement driving device.

[0044] After the above parameters are determined, the specific processing technology process is as follows: firstly, the axial tooth profile is processed, and disc-shaped milling cutter processing or finger-shaped milling cutter processing is used, in the processing, the cylindrical tooth blank is fixed, the milling cutter moves along the axial direction of the cylindrical tooth blank, after completing the processing once, the cylindrical tooth blank is turned by one tooth and then continues to be processed, until all the axial tooth profiles are processed, forming a cylindrical gear-shaped dual-purpose cylindrical tooth blank. The milling method can ensure that the axial tooth height is not affected by the thermal deformation of the tool when processing a long axial dimension.

[0045] Then, the circumferential tooth profile arranged along the axial direction of the cylindrical tooth blank is further processed on the basis of the dual-purpose cylindrical tooth blank, and the rolling cutter is used for processing; in the processing process, the rotation center axis of the rolling cutter is parallel to the dual-purpose cylindrical tooth blank, the rolling cutter cylinder is tangent to the dual-purpose cylindrical tooth blank, the rolling cutter rotates at high speed in the processing, and there is a radial feeding motion to ensure the processing tooth height, and at the same time, the dual-purpose cylindrical tooth blank also rotates at a fixed axis. The above axial and circumferential processing can complete the processing of the dual-purpose cylindrical gear.

[0046] The working principle of the application is as follows:

[0047] When the output shaft of the axial and circumferential movement driving device needs to perform telescopic movement, the telescopic steering engine 3 rotates to drive the axial driving gear 12 and the axial transmission gear 11 to rotate, and then drive the output shaft and the dual-purpose cylindrical gear 7 to slide along the axial direction.

[0048] When the output shaft of the axial and circumferential movement driving device needs to perform rotary movement, the rotary steering engine 4 rotates to drive the circumferential driving gear 10 and the circumferential transmission gear 9 to rotate, and then drive the output shaft and the dual-purpose cylindrical gear 7 to rotate around the axial line thereof.

[0049] Therefore, the axial movement and the circumferential rotation of the output shaft are realized, the circumferential rotation and the axial movement of the output shaft are independent of each other, the output shaft can drive the load to perform the telescopic movement, the circumferential rotation and the helical movement, the application range of the application is greatly increased, and the driving structure of the equipment which needs to move and rotate at the same time is more compact.

Claims

1. An axial and circumferential movement drive comprising a housing (2) and an output shaft (6); characterized in that: The extension drive steering engine (3), the rotation drive steering engine (4), the dual-purpose cylindrical gear (7), the circumferential transmission gear (9) and the axial transmission gear (11) are further included; the output shaft and the shell (2) form a cylindrical pair; the circumferential transmission gear (9) and the axial transmission gear (11) are both rotationally connected in the shell (2); the axis of the circumferential transmission gear (9) is parallel to the axis of the output shaft (6); the axis of the axial transmission gear (11) is perpendicular to the axis of the output shaft (6); the extension drive steering engine (3) and the rotation drive steering engine (4) are both fixed on the shell (2) and are used for driving the axial transmission gear (11) and the circumferential transmission gear (9) respectively. The dual-purpose cylindrical gear (7) is coaxially fixed on the output shaft (6); a plurality of gear tooth queues are uniformly distributed along the circumferential direction of the dual-purpose cylindrical gear (7) on the outer circumferential surface of the dual-purpose cylindrical gear (7); each gear tooth queue includes a plurality of dual-purpose gear teeth which are sequentially and equally spaced along the axial direction of the dual-purpose cylindrical gear (7). Each dual-purpose gear tooth sequentially arranged along the axial direction of the dual-purpose cylindrical gear (7) is in the form of a rack and can be engaged with the axial transmission gear (11); each dual-purpose gear tooth sequentially arranged along the circumferential direction of the dual-purpose cylindrical gear (7) is in the form of a cylindrical gear and can be engaged with the axial transmission gear (11); during operation, the circumferential transmission gear (9) rotates to drive the dual-purpose cylindrical gear (7) to rotate; the axial transmission gear (11) rotates to drive the dual-purpose cylindrical gear (7) to move axially.

2. An axial and circumferential movement drive according to claim 1, characterized in that: The two side surfaces of each dual-purpose gear tooth along the tangential direction of the dual-purpose cylindrical gear (7) are circumferential engagement tooth surfaces; the circumferential engagement tooth surfaces are specifically involute tooth surfaces of a cylindrical spur gear and are matched with the tooth surfaces on the circumferential transmission gear (9) for transmission.

3. The axial and circumferential movement drive of claim 1, wherein: The two side surfaces of each dual-purpose gear tooth along the axial direction of the dual-purpose cylindrical gear (7) are axial engagement tooth surfaces; the axial engagement tooth surfaces are specifically involute tooth surfaces of a straight rack and are matched with the tooth surfaces on the axial transmission gear (11) for transmission.

4. The axial and circumferential motion drive of claim 1, wherein: The rotation shaft of the extension drive steering engine (3) is fixed with an axial driving gear (12); the axial driving gear (12) is engaged with the axial transmission gear (11); the rotation shaft of the rotation drive steering engine (4) is fixed with a circumferential driving gear (10); the circumferential driving gear (10) is engaged with the circumferential transmission gear (9).

5. The axial and circumferential motion drive of claim 1, wherein: The tooth width B9 of the circumferential transmission gear (9) is in the range of m 7' *4≤B9≤m 7' *6; the tooth width B 11 of the axial transmission gear (11) is in the range of m7*3≤B 11 ≤m7*5; m 7' and m7 are the axial and circumferential module of the dual-purpose stud gear.

6. An axial and circumferential movement drive according to claim 1, characterized in that: The dual-purpose cylindrical gear is obtained by the following method: using a disc-shaped milling cutter or a finger-shaped milling cutter to process a cylindrical gear blank into a dual-purpose cylindrical gear blank in the form of a cylindrical spur gear; using a hob to process the dual-purpose cylindrical gear blank; during the processing, the hob rotates and feeds along the radial direction of the dual-purpose cylindrical gear blank, and at the same time, the dual-purpose cylindrical gear blank rotates around its own axis, so that the tooth profile on the dual-purpose cylindrical gear blank is divided into an array of dual-purpose gear teeth which are uniformly arranged on the outer circumferential surface of the dual-purpose cylindrical gear.

7. An axial and circumferential movement drive as claimed in claim 1, characterized in that: A cover (1) is detachably fixed at the opening of the end portion of the shell (2); the outer end of the output shaft (6) extends out of the cover (1); the output shaft and the shell (2) are connected through a shaft sleeve (5).

8. An axial and circumferential movement drive as claimed in claim 7, characterized in that: A plurality of balls are uniformly installed on the inner side surface of the shaft sleeve (5); the balls and the shaft sleeve (5) form a spherical pair.

9. An axial and circumferential movement drive as claimed in claim 1, characterized in that: The circumferential transmission gear (9) is an internal gear, and its outer circumferential surface is coaxially connected with the shell (2) through a bearing (8); the output shaft is eccentrically arranged in the shell (2).

10. The method of claim 1, wherein: the axial and circumferential movement drive device is a motorized device. When the output shaft of the axial and circumferential motion driving device needs to perform telescopic motion, the telescopic driving rudder (3) rotates to drive the axial transmission gear (11) to rotate, thereby driving the output shaft and the dual-purpose spur gear (7) to slide along the axial direction; When the output shaft of the axial and circumferential motion driving device needs to perform rotational motion, the rotational driving rudder (4) rotates to drive the circumferential transmission gear (9) to rotate, thereby driving the output shaft and the dual-purpose spur gear (7) to rotate around the axial line thereof.

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