Cam tool changing driving device

Abstract

The invention belongs to the technical field of machine tool tool changing, and relates to a cam tool changing driving device which comprises a shell, an output shaft, a driving structure, a first transmission structure and a second transmission structure. Under the action of the driving structure and the first transmission structure, the output shaft can be in a first working state or a third working state, the cylindrical cam can be driven to rotate under the action of the driving structure, the rotation of the cylindrical cam can enable the first roller to slide in the curve groove, and therefore the connecting part can be driven to rotate; and the output shaft can be in a second working state. Compared with the mode that a plurality of connecting rods are used for controlling rotation of the output shaft, the arrangement of the cylindrical cam and the roller enables the structure of the whole cam tool changing driving device to be more compact, transmission resistance can be reduced on the premise that low back clearance or even zero back clearance is guaranteed, transmission precision and transmission efficiency are improved, and therefore tool changing precision and tool changing efficiency can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of machine tool tool changing, and in particular to a cam tool changing driving device. Background Art

[0002] At present, there are two main ways to replace tools in machine tools. One is to achieve tool exchange by relative movement between the tool magazine and the machine tool spindle. However, this method requires pulling out the used tool and placing it in the tool magazine. Then, take out the new tool from the tool magazine and install it on the machine tool spindle. The two actions of pulling out and installing the tool cannot be performed at the same time. The other is to use a cam tool changing mechanism to exchange tools. Specifically, the tool changing arm is controlled to move back and forth and rotate through the cam tool changing drive device to remove the old tool from the spindle while taking out the new tool from the tool magazine. After the two exchange positions, they are placed in the tool magazine and spindle respectively. Compared with tool exchange through relative movement, the cam box can improve tool change efficiency.

[0003] However, in the existing cam tool change drive devices, most of them control the rotation of the tool change arm through the cooperation of the cam plate, the connecting rod mechanism, the rack, the gear and the output shaft. Specifically, a rotation curve is set on the cam plate, and the rack is connected to the rotation curve through the connecting rod mechanism. The rotation curve can drive the rack to move during the rotation process, thereby driving the gear to rotate, thereby driving the output shaft to rotate, and then driving the tool change arm to rotate. Since it is necessary to ensure that the rack cannot be offset during the movement, the connecting rod mechanism often includes multiple connecting rods. In order to ensure the stability of the operation of the connecting rod mechanism, it is necessary to ensure the length of each connecting rod, which leads to an increase in the size occupied by the entire cam tool change mechanism. In addition, the more connecting rods there are, the longer it takes to drive the rack to move, thereby reducing the tool change efficiency of the entire cam tool change mechanism.

[0004] Therefore, the above problems need to be solved urgently. Summary of the invention

[0005] The object of the present invention is to provide a cam tool-changing drive device to improve the tool-changing efficiency of a machine tool spindle.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] A cam tool-changing drive device, used for driving a tool-changing arm to change tools, comprises a housing, an output shaft, a driving structure, a first transmission structure and a second transmission structure, wherein the output shaft is arranged inside the housing, one end of the output shaft can extend to the outside of the housing and is connected to the tool-changing arm, the output shaft has a first working state of driving the tool-changing arm away from the housing, a second working state of rotating around its own axis and a third working state of driving the tool-changing arm close to the housing; the driving structure is arranged inside the housing, and the driving structure has a first output part and a second output part, the first output part is connected to the output shaft through the first transmission structure, so that the output shaft is in the first working state or the third working state, the second output part is connected to the output shaft through the second transmission structure, so that the output shaft is in the second working state;

[0008] Wherein, the second transmission structure comprises:

[0009] A cylindrical cam, drivingly connected to the second output part so that the cylindrical cam can rotate around its own axis, a straight groove and a plurality of curved grooves are arranged on the cylindrical surface of the cylindrical cam, the length direction of the curved groove extends along the axial direction of the cylindrical cam, and the plurality of curved grooves are evenly distributed along the circumference of the cylindrical cam, the length direction of the straight groove extends along the circumference of the cylindrical cam, and the straight groove is arranged between two adjacent curved grooves;

[0010] A connecting portion, drivingly connected to the output shaft;

[0011] A plurality of first rollers are evenly spaced and fixed on the outer peripheral wall of the connecting portion, any one of the first rollers can extend into the curved groove or the straight groove, and the first roller can fit with the side wall of the curved groove or the straight groove, when the first roller is in the curved groove, the output shaft is in the first working state or the third working state, and when the first roller is in the straight groove, the output shaft is in the second working state.

[0012] Preferably, the straight groove includes a first groove body, a second groove body and a third groove body arranged in sequence, the first groove body and the third groove body are arranged parallel to the curved groove, and the first groove body and the third groove body have an opening at one end away from the second groove body, and the length of the second groove body extends along the circumference of the cylindrical cam.

[0013] Preferably, the plurality of curved grooves are divided into a plurality of first curved grooves and a plurality of second curved grooves, wherein the first curved grooves and the second curved grooves have opposite inclination directions and are respectively located at two ends of the linear groove;

[0014] The first slot body is disposed adjacent to the first curved slot, and the first slot body is disposed parallel to the first curved slot;

[0015] The third slot body is disposed adjacent to the second curved slot, and the third slot body is disposed parallel to the second curved slot.

[0016] Preferably, the connecting portion comprises:

[0017] A connecting shaft, a plurality of first rollers are evenly spaced and arranged on the connecting shaft;

[0018] A driving gear, coaxially fixedly disposed on the connecting shaft;

[0019] The driven gear is meshed with the driving gear, and the driven gear is sleeved on the output shaft and can rotate synchronously with the output shaft.

[0020] Preferably, the cross section of the portion of the output shaft located inside the housing is polygonal, and the center hole of the driven gear is contoured to the output shaft.

[0021] Preferably, the connecting shaft is rotatably disposed inside the housing via a ball bearing.

[0022] Preferably, the driving structure further comprises a turntable rotatable around its own axis, and the second output portion is a synchronization shaft, and the synchronization shaft is arranged between the turntable and the cylindrical cam.

[0023] Preferably, the first transmission structure is a cam profile groove arranged on the rotating disk;

[0024] The first transmission structure comprises:

[0025] A bushing is fixed to the output shaft, and an annular groove is provided on the bushing along the circumference of the output shaft;

[0026] A transmission rod, one end of which is hinged to the housing;

[0027] A second roller is disposed at one end of the transmission rod away from the housing and can extend into the annular groove, and the second roller can fit with the side wall of the annular groove;

[0028] The third roller is arranged at the middle part of the transmission rod and can extend to the cam profile groove, so that when the rotating disk rotates, the output shaft is intermittently in the first working state and the third working state.

[0029] Preferably, the cam profile groove comprises a first stop segment, an extension segment, a second stop segment and a retraction segment connected end to end, the first stop segment has a consistent spacing with the rotation axis of the turntable, the second stop segment has a consistent spacing with the rotation axis, and the spacing between the first stop segment and the rotation axis is greater than the spacing between the second stop segment and the rotation axis;

[0030] The distance between the protruding section and the rotation axis gradually decreases;

[0031] The distance between the retracted section and the rotation axis gradually increases.

[0032] Preferably, the cam tool-changing drive device further comprises an encoder, and the encoder is arranged on the synchronization shaft to detect the rotation angle of the synchronization shaft.

[0033] Beneficial effects of the present invention:

[0034] The cam tool-changing drive device of the present invention can put the output shaft in the first working state or the third working state under the action of the driving structure and the first transmission structure, and can drive the cylindrical cam to rotate under the action of the driving structure. The rotation of the cylindrical cam can make the first roller slide in the curved groove, thereby driving the connecting part to rotate, and then the output shaft can be put in the second working state. The sliding of the first roller in the linear groove can put the output shaft in the first working state or the third working state. Compared with using multiple connecting rods to control the rotation of the output shaft, the setting of the cylindrical cam and the roller can make the structure of the entire cam tool-changing drive device more compact, and can reduce the transmission resistance under the premise of ensuring low backlash or even zero backlash, improve the transmission accuracy and transmission efficiency, and thus improve the tool-changing accuracy and tool-changing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic structural diagram of a cam tool-changing drive device and a tool-changing arm in an embodiment of the present invention;

[0036] Figure 2 This is one of the cross-sectional views of the cam tool changing drive device in the embodiment of the present invention;

[0037] Figure 3 This is the second cross-sectional view of the cam tool changing drive device in the embodiment of the present invention;

[0038] Figure 4 is a schematic structural diagram of a rotating disk and a cam profile groove in an embodiment of the present invention;

[0039] Figure 5 is a schematic structural diagram of a first curved groove in an embodiment of the present invention;

[0040] Figure 6is a schematic structural diagram of a second curved groove in an embodiment of the present invention;

[0041] Figure 7 Schematic diagram of the structure of the linear groove in the embodiment of the present invention.

[0042] In the figure:

[0043] 100, tool changing arm; 200, tool;

[0044] 1. Housing; 2. Output shaft;

[0045] 3. Driving structure; 31. Rotating plate; 32. Cam profile groove; 321. First rest section; 322. Extending section; 323. Second rest section; 324. Retracting section; 33. Synchronous shaft; 34. Frequency conversion motor; 35. Active synchronous wheel; 36. Synchronous belt; 37. Driven synchronous wheel; 38. Worm;

[0046] 4. first transmission structure; 41. bushing; 411. annular groove; 42. transmission rod; 43. second roller; 44. third roller;

[0047] 5. Second transmission structure; 51. Cylindrical cam; 511. Straight groove; 5111. First groove body; 5112. Second groove body; 5113. Third groove body; 512. First curved groove; 513. Second curved groove; 52. Connecting part; 521. Connecting shaft; 522. Driving gear; 523. Driven gear; 524. Ball bearing; 53. First roller;

[0048] 6. Encoder. DETAILED DESCRIPTION

[0049] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0050] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0052] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0053] See also Figure 1 In order to improve the tool changing efficiency of the machine tool spindle, a cam tool changing drive device and a tool changing arm 100 are usually used in cooperation. The tool changing arm 100 has two clamping parts, and the two clamping parts are respectively opposite to the machine tool spindle and the tool magazine. Under the action of the cam tool changing drive device, the tool changing arm 100 can be controlled to reciprocate and rotate. Specifically, the cam tool changing drive device can drive the tool changing arm 100 to approach the machine tool spindle and the tool magazine, and under the action of the clamping part, the used tool 200 on the machine tool spindle and the new tool 200 in the tool magazine can be clamped. Then the cam tool changing drive device can drive the tool changing arm 100 away from the machine tool spindle and the tool magazine. In this process, the tool can be unloaded and taken out. Then the cam tool changing drive device can control the tool changing arm 100 to rotate, so that the positions of the two tools 200 can be changed. Finally, under the action of the cam tool changing drive device, the installation of the new tool 200 and the storage of the old tool 200 are completed.

[0054] However, most of the existing cam tool changing drive devices control the rotation of the tool changing arm 100 through the cooperation of the cam plate, connecting rod mechanism, rack, gear and output shaft 2. According to multiple tests and user feedback, the cam plate takes a long time to control the transmission of the connecting rod mechanism, and the entire connecting rod mechanism occupies a large space, which leads to an increase in the size occupied by the cam tool changing mechanism.

[0055] To this end, a cam tool changing drive device is proposed in this embodiment. By utilizing the cooperation of the cylindrical cam 51 and the first roller 53 to replace the connecting rod mechanism, the cam tool changing drive device can be made more compact, thereby reducing the transmission ratio of the cam tool changing drive device and improving the tool changing efficiency.

[0056] Specifically, see Figure 2 and Figure 3 The cam tool-changing drive device comprises a housing 1, an output shaft 2, a driving structure 3, a first transmission structure 4 and a second transmission structure 5. The output shaft 2 is arranged inside the housing 1, one end of the output shaft 2 can extend to the outside of the housing 1 and is connected to the tool-changing arm 100. The output shaft 2 has a first working state in which the tool-changing arm 100 is driven away from the housing 1, a second working state in which the tool-changing arm 100 rotates around its own axis, and a third working state in which the tool-changing arm 100 is driven close to the housing 1; the driving structure 3 is arranged inside the housing 1, and the driving structure 3 has a first output part and a second output part that rotate synchronously, the first output part is connected to the output shaft 2 through the first transmission structure 4, so that the output shaft 2 is in the first working state or the third working state, and the second output part is connected to the output shaft 2 through the second transmission structure 5, so that the output shaft 2 is in the second working state.

[0057] The second transmission structure 5 includes a cylindrical cam 51, a connecting portion 52 and a plurality of first rollers 53. The cylindrical cam 51 is transmission-connected to the second output portion so that the cylindrical cam 51 can rotate around its own axis. A linear groove 511 and a plurality of curved grooves are arranged on the cylindrical surface of the cylindrical cam 51. The length direction of the curved groove extends along the axial direction of the cylindrical cam 51, and the plurality of curved grooves are uniformly distributed along the circumference of the cylindrical cam 51. The length direction of the linear groove 511 extends along the circumference of the cylindrical cam 51, and the linear groove 511 is arranged Placed between two adjacent curved grooves; the connecting part 52 is transmission-connected to the output shaft 2; a plurality of first rollers 53 are evenly spaced and fixed on the outer peripheral wall of the connecting part 52, any one of the first rollers 53 can extend into the curved groove or the straight groove 511, and the first roller 53 can fit with the side wall of the curved groove or the straight groove 511, when the first roller 53 is in the curved groove, the output shaft 2 is in the first working state or the third working state, and when the first roller 53 is in the straight groove 511, the output shaft 2 is in the second working state.

[0058] It can be understood that the output shaft 2 can be placed in the first working state or the third working state under the action of the driving structure 3 and the first transmission structure 4, and the cylindrical cam 51 can be driven to rotate under the action of the driving structure 3. The rotation of the cylindrical cam 51 can make the first roller 53 slide in the curved groove, thereby driving the connecting part 52 to rotate, and then the output shaft 2 can be placed in the second working state. The sliding of the first roller 53 in the linear groove 511 can put the output shaft 2 in the first working state or the third working state. Compared with using multiple connecting rods to control the rotation of the output shaft 2, the setting of the cylindrical cam 51 and the roller can not only make the structure of the entire cam tool change drive device more compact, but also reduce the transmission resistance under the premise of ensuring low backlash or even zero backlash, improve the transmission accuracy and transmission efficiency, and thus improve the tool change accuracy and tool change efficiency.

[0059] Among them, when the cylindrical cam 51 rotates, it can drive the curved groove to rotate, so that the first roller 53 can enter the curved groove through one end of the curved groove, and as the cylindrical cam 51 continues to rotate, the first roller 53 moves out of the groove from the other end of the curved groove, and the next first roller 53 enters the curved groove, and so on. The cycle can drive the connecting part 52 to rotate. At this time, the output shaft 2 is in the second working state. When the output shaft 2 is in the first working state or the third working state, the first roller 53 enters the linear groove 511, thereby stopping the rotation of the connecting part 52.

[0060] For further information, see Figure 4 The linear groove 511 includes a first groove body 5111, a second groove body 5112 and a third groove body 5113 which are arranged in sequence. The first groove body 5111 and the third groove body 5113 are arranged in parallel with the curved groove, and an opening is provided at one end of the first groove body 5111 and the third groove body 5113 which are away from the second groove body 5112. The length of the second groove body 5112 extends along the circumferential direction of the cylindrical cam 51. It can be understood that the first roller 53 is carried out in the linear groove 511 by the first groove body 5111. At this time, the output shaft 2 is in the second working state. When the first roller 53 enters the second groove body 5112 from the first groove body 5111, the connecting part 52 stops rotating, that is, the output shaft 2 switches to the first working state or the third working state. With such an arrangement, the output shaft 2 can switch between the first working state, the second working state and the third working state, thereby improving the tool changing efficiency.

[0061] For further information, see Figure 4 , Figure 5 and Figure 6, the multiple curved grooves are divided into multiple first curved grooves and multiple second curved grooves, the first curved grooves and the second curved grooves have opposite inclination directions and are respectively located at the two ends of the linear groove 511; the first groove body 5111 is arranged adjacent to the first curved groove, and the first groove body 5111 is arranged parallel to the first curved groove; the third groove body 5113 is arranged adjacent to the second curved groove, and the third groove body 5113 is arranged parallel to the second curved groove. It can be understood that the cylindrical cam 51 is divided into two parts in the circumferential direction, one part of which is evenly distributed with the first curved grooves, and the other part is evenly distributed with the second curved grooves, and two linear grooves 511 are provided, so that the first curved groove and the second curved groove can be separated, and under the action of the linear groove 511, the rotation direction of the connecting part 52 can be adjusted, so that the tool changing arm 100 can be controlled to rotate in the opposite direction, thereby improving the tool changing efficiency of the cam tool changing drive device.

[0062] In this embodiment, the connecting portion 52 includes a connecting shaft 521, a driving gear 522 and a driven gear 523, a plurality of first rollers 53 are evenly spaced and arranged on the connecting shaft 521; the driving gear 522 is coaxially fixedly arranged on the connecting shaft 521; the driven gear 523 is meshed with the driving gear 522, and the driven gear 523 is sleeved on the output shaft 2 and can rotate synchronously with the output shaft 2. It can be understood that the connecting shaft 521 can rotate around its own axis under the cooperation of the first rollers 53 and the curved groove, and then the output shaft 2 can be driven to rotate under the action of the driving gear 522 and the driven gear 523.

[0063] In actual application, the connecting shaft 521 is arranged inside the shell 1 through the ball bearing 524, and the driving gear 522 is fixed on the connecting shaft 521, the driven gear 523 is fixed inside the shell 1 through the connecting seat, and the driven gear 523 is meshed with the driving gear 522, and the output shaft 2 is slidably arranged at the center hole of the driven gear 523, that is, when the output shaft 2 is in the first working state and the second working state, the output shaft 2 can slide in the center hole, and in addition, when the output shaft 2 is in the second working state, the output shaft 2 stops sliding and can rotate synchronously with the driven gear 523.

[0064] Specifically, the cross section of the output shaft 2 located inside the housing 1 is polygonal, and the center hole of the driven gear 523 is contoured with the output shaft 2. This arrangement not only ensures that the output shaft 2 can slide in the center hole, but also forms a circumferential limit for the output shaft 2, so that the output shaft 2 and the driven gear 523 rotate synchronously.

[0065] In particular, the connecting shaft 521 is rotatably disposed inside the housing 1 via a ball bearing 524. It is understandable that the position of the connecting shaft 521 can be adjusted under the action of the ball bearing 524, so that the first roller 53 can fit the side wall of the curved groove or the linear groove 511, thereby eliminating the backlash between the first roller 53 and the curved groove or the linear groove 511, thereby further improving the tool changing accuracy.

[0066] In some other feasible embodiments, the connecting portion 52 includes a sleeve and a connecting piece. The sleeve is arranged on the housing 1 through the connecting piece and is sleeved on the output shaft 2. A guide assembly is arranged between the output shaft 2 and the sleeve. The guide assembly can not only prevent the output shaft 2 from being offset when it is in the first working state or the third working state, but also form a circumferential limit for the output shaft 2 so that the output shaft 2 and the sleeve rotate synchronously. A plurality of first rollers 53 are evenly arranged on the outer circumference of the sleeve, and the output shaft 2 is in the second working state with the cooperation of the first rollers 53 and the curved grooves.

[0067] In this embodiment, the driving structure 3 also includes a turntable 31, which can rotate around its own axis under the action of a power source, and the first output part and the second output part are respectively arranged on the two sides of the turntable 31, wherein the first output part is arranged on the cam contour groove 32 on the turntable 31; the second output part is a synchronization shaft 33, and the synchronization shaft 33 is arranged between the turntable 31 and the cylindrical cam 51, so that the turntable 31 and the cylindrical cam 51 rotate synchronously.

[0068] Exemplarily, the driving structure 3 also includes a variable frequency motor 34, on the rotating shaft of which is fixed an active synchronous wheel 35, which is connected to a driven synchronous wheel 37 via a synchronous belt 36, and can drive the driven synchronous shaft 33 to rotate synchronously under the action of the synchronous belt 36, and the driven synchronous shaft 33 is connected to the turntable 31 via a worm gear 38.

[0069] Furthermore, the first transmission structure 4 includes a bushing 41, a transmission rod 42, a second roller 43 and a third roller 44. The bushing 41 is fixed to the output shaft 2, and an annular groove 411 is provided on the bushing 41 along the circumference of the output shaft 2; one end of the transmission rod 42 is hinged to the housing 1; the second roller 43 is provided at the end of the transmission rod 42 away from the housing 1, and can extend into the annular groove 411, and the second roller 43 can fit with the side wall of the annular groove 411; the third roller 44 is provided in the middle of the transmission rod 42, and can extend to the cam profile groove 32, so that when the turntable 31 rotates, the output shaft 2 is intermittently in the first working state and the third working state. It can be understood that the transmission rod 42 is arranged inside the shell 1 through the hinge shaft, and is connected to the output shaft 2 through the second terminal. Under the action of the hinge shaft and the second terminal, the third terminal can be in a preset position, and the cam contour groove 32 can be driven to rotate during the rotation of the turntable 31, so that the third terminal and the cam contour groove 32 can slide relative to each other. At this time, if the distance between the cam contour groove 32 and the rotation axis of the turntable 31 gradually increases or decreases, it will push the transmission rod 42 to rotate, and then push the output shaft 2 to move along its own axial direction, that is, the output shaft 2 can be in the first working state and the second working state.

[0070] Specifically, see Figure 7The cam profile groove 32 includes a first rest section 321, an extended section 322, a second rest section 323 and a retracted section 324 connected end to end. The distance between the first rest section 321 and the rotation axis of the turntable 31 is consistent at all locations, the distance between the second rest section 323 and the rotation axis is consistent at all locations, and the distance between the first rest section 321 and the rotation axis is greater than the distance between the second rest section 323 and the rotation axis; the distance between the extended section 322 and the rotation axis gradually decreases; the distance between the retracted section 324 and the rotation axis gradually increases. It can be understood that when the third terminal is in the first rest section 321, since the spacing between the first rest section 321 and the rotation axis of the turntable 31 is consistent, the third terminal is in a preset position, that is, the output shaft 2 does not move axially, and the first roller 53 is in the curved groove at this time, thereby driving the cylindrical cam 51 to rotate; when the third terminal is in the range of the extension section 322, since the spacing between the extension section 322 and the rotation axis gradually decreases, the position of the third terminal changes, thereby driving the output shaft 2 to move axially, and the tool changing arm 100 can be pushed to move in a direction away from the housing 1, and the first roller 53 is in the linear groove 511 at this time, that is, the output shaft 2 is in the first working state at this time, and when the third terminal is in the range of the second rest section 323, Since the spacing between the second rest section 323 and the rotation axis is consistent, the position of the third terminal remains unchanged, that is, the output shaft 2 does not move axially. At this time, the first roller 53 is again in the curved groove, thereby driving the cylindrical cam 51 to rotate. When the third terminal is in the range of the retracted section 324, since the spacing between the retracted section 324 and the rotation axis gradually increases, the position of the third terminal changes again, thereby driving the output shaft 2 to move axially and pushing the tool changing arm 100 to move in the direction close to the housing 1. At this time, the first roller 53 is again in the linear groove 511, that is, the output shaft 2 is in the third working state at this time to complete the replacement of the tool 200. With the continuous rotation of the turntable 31, the third terminal can be again in the first rest section 321.

[0071] In addition, the cam tool change drive device further includes an encoder 6, which is disposed on the synchronization shaft 33 to detect the rotation angle of the synchronization shaft 33. The encoder 6 is disposed outside the housing 1, so that the rotation state of the turntable 31 can be monitored, thereby facilitating the staff to monitor the position of the third terminal.

[0072] The cam tool changing drive device in the present embodiment controls the rotation of the turntable 31, thereby driving the first transmission structure 4 and the second transmission structure 5 to alternately apply force to the output shaft 2, so as to control the output shaft 2 to switch between the first working state, the second working state and the third working state, wherein the first transmission structure 4 can apply an axial force to the output shaft 2, thereby enabling the output shaft 2 to reciprocate, so that the output shaft 2 is intermittently in the first working state and the third working state, when the output shaft 2 does not move axially, the second transmission structure 5 can apply a circumferential force to the output shaft 2, thereby enabling the output shaft 2 to rotate around its own axis, so that the output shaft 2 is in the second working state, under the action of the first transmission structure 4 and the second transmission structure 5, the output shaft 2 can be intermittently switched between the first working state, the second working state and the third working state, thereby improving the tool changing efficiency.

[0073] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A cam tool-changing drive device, used for driving a tool-changing arm (100) to change tools, comprising a housing (1), an output shaft (2), a driving structure (3), a first transmission structure (4) and a second transmission structure (5), wherein the output shaft (2) is arranged inside the housing (1), one end of the output shaft (2) can extend to the outside of the housing (1) and be connected to the tool-changing arm (100), and the output shaft (2) has a first working state in which the tool-changing arm (100) is driven away from the housing (1), a second working state in which the tool-changing arm (100) is rotated around its own axis, and a second working state in which the tool-changing arm (100) is driven to move away from the housing (1), and a second working state in which the tool-changing arm (100) is driven to move away from the housing (1). The tool changing arm (100) is moved close to the housing (1) to a third working state; the driving structure (3) is arranged inside the housing (1), and the driving structure (3) comprises a first output part and a second output part which rotate synchronously, the first output part is connected to the output shaft (2) through the first transmission structure (4), so that the output shaft (2) is in the first working state or the third working state, and the second output part is connected to the output shaft (2) through the second transmission structure (5), so that the output shaft (2) is in the second working state; It is characterized in that The second transmission structure (5) comprises: A cylindrical cam (51) is drivingly connected to the second output part so that the cylindrical cam (51) can rotate around its own axis. A straight groove (511) and a plurality of curved grooves are arranged on the cylindrical surface of the cylindrical cam (51). The length direction of the curved groove extends along the axial direction of the cylindrical cam (51), and the plurality of curved grooves are evenly distributed along the circumference of the cylindrical cam (51). The length direction of the straight groove (511) extends along the circumference of the cylindrical cam (51), and the straight groove (511) is arranged between two adjacent curved grooves. A connecting portion (52) drivingly connected to the output shaft (2); A plurality of first rollers (53) are evenly spaced and fixed on the outer peripheral wall of the connecting portion (52); any one of the first rollers (53) can extend into the curved groove or the straight groove (511), and the first roller (53) can fit with the side wall of the curved groove or the straight groove (511); when the first roller (53) is in the curved groove, the output shaft (2) is in the first working state or the third working state; when the first roller (53) is in the straight groove (511), the output shaft (2) is in the second working state.

2. The cam tool change drive device according to claim 1, It is characterized in that The straight groove (511) includes a first groove body (5111), a second groove body (5112) and a third groove body (5113) which are arranged in sequence, the first groove body (5111) and the third groove body (5113) are arranged in parallel with the curved groove, and the first groove body (5111) and the third groove body (5113) are provided with an opening at one end away from the second groove body (5112), and the length of the second groove body (5112) extends along the circumference of the cylindrical cam (51).

3. The cam tool change drive device according to claim 2, It is characterized in that The plurality of curved grooves are divided into a plurality of first curved grooves and a plurality of second curved grooves, wherein the first curved grooves and the second curved grooves have opposite inclination directions and are respectively located at two ends of the linear groove (511); The first slot body (5111) is arranged adjacent to the first curved slot, and the first slot body (5111) is arranged parallel to the first curved slot; The third groove body (5113) is arranged adjacent to the second curved groove, and the third groove body (5113) is arranged parallel to the second curved groove.

4. The cam tool change drive device according to claim 1, It is characterized in that The connecting portion (52) comprises: A connecting shaft (521), a plurality of first rollers (53) being evenly spaced and arranged on the connecting shaft (521); A driving gear (522) coaxially fixedly disposed on the connecting shaft (521); The driven gear (523) is meshed with the driving gear (522); the driven gear (523) is sleeved on the output shaft (2) and can rotate synchronously with the output shaft (2).

5. The cam tool change drive device according to claim 4, It is characterized in that The cross section of the portion of the output shaft (2) located inside the housing (1) is polygonal, and the center hole of the driven gear (523) is contoured to the output shaft (2).

6. The cam tool change driving device according to claim 4, It is characterized in that The connecting shaft (521) is rotatably arranged inside the housing (1) via a ball bearing (524).

7. The cam tool change driving device according to claim 1, It is characterized in that The driving structure (3) further comprises a rotating disk (31) which can rotate around its own axis, and the second output part is a synchronous shaft (33), and the synchronous shaft (33) is arranged between the rotating disk (31) and the cylindrical cam (51).

8. The cam tool changing drive device according to claim 7, It is characterized in that The first transmission structure (4) is arranged in a cam profile groove (32) on the rotating disk (31); The first transmission structure (4) comprises: A bushing (41) is fixed to the output shaft (2), and an annular groove (411) is provided on the bushing (41) along the circumference of the output shaft (2); A transmission rod (42), one end of which is hinged to the housing (1); A second roller (43) is arranged at an end of the transmission rod (42) away from the housing (1) and is capable of extending into the annular groove (411), and the second roller (43) is capable of fitting with a side wall of the annular groove (411); The third roller (44) is arranged at the middle part of the transmission rod (42) and can extend to the cam profile groove (32), so that when the rotating disk (31) rotates, the output shaft (2) is intermittently in the first working state and the third working state.

9. The cam tool change driving device according to claim 8, It is characterized in that The cam profile groove (32) comprises a first stop section (321), an extension section (322), a second stop section (323) and a retracted section (324) connected end to end, the first stop section (321) having a consistent spacing with the rotation axis of the rotating disk (31), the second stop section (323) having a consistent spacing with the rotation axis, and the spacing between the first stop section (321) and the rotation axis is greater than the spacing between the second stop section (323) and the rotation axis; The distance between the protruding section (322) and the rotation axis gradually decreases; The distance between the retracted section (324) and the rotation axis gradually increases.

10. The cam tool changing drive device according to claim 7, It is characterized in that The cam tool-changing drive device further comprises an encoder (6), wherein the encoder (6) is arranged on the synchronization shaft (33) to detect the rotation angle of the synchronization shaft (33).

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