CN217920264U

CN217920264U - Mechanical arm structure

Info

Publication number: CN217920264U
Application number: CN202222379572.8U
Authority: CN
Inventors: 王丙讯; 张成林; 杨森
Original assignee: Shandong University of Science and Technology
Current assignee: Shandong University of Science and Technology
Priority date: 2022-09-08
Filing date: 2022-09-08
Publication date: 2022-11-29
Anticipated expiration: 2032-09-08

Abstract

The utility model discloses a mechanical arm structure relates to artificial limb joint transmission technical field. Including rotation axis joint subassembly, underarm axle joint subassembly, upper arm axle joint subassembly, ball wrist joint subassembly, snatch the manipulator subassembly, rotation axis joint subassembly pass through steering wheel and axis of rotation with underarm axle joint subassembly transmission is connected, underarm axle joint subassembly pass through steering wheel and underarm joint connecting rod with upper arm axle joint subassembly transmission is connected, upper arm axle joint subassembly pass through steering wheel and forearm joint connecting rod with ball wrist joint subassembly transmission is connected, ball wrist joint subassembly pass through the rudder frame with fixed connection can be dismantled to the snatch the manipulator subassembly, it utilizes lead screw motor to carry out the centre gripping to snatch the manipulator subassembly. The utility model discloses a structure design of personification, running state, position angle etc. are controlled through the steering wheel to each articular activity for control more accurate, to snatching or putting in of article more smoothly.

Description

Mechanical arm structure

Technical Field

The utility model relates to an artificial limb joint transmission technical field especially relates to a mechanical arm structure.

Background

With the development of industrial technology, industrial robots are widely involved in various links of industrial production. Mechanical grabbing is the main operation task of an industrial robot for picking or releasing a product, and in the mechanical grabbing process, the picking or releasing action is realized through the movement of each mechanical joint. However, the existing mechanical arm assembly has a complex structure, cannot grab in multiple directions and angles, and cannot move freely like the upper limbs of people.

SUMMERY OF THE UTILITY MODEL

Can't carry out the nimble operation of snatching of multi-direction, multi-angle to above-mentioned arm structure, the utility model provides a arm structure.

In order to solve the technical problem, the utility model discloses a following technical scheme:

the utility model provides a mechanical arm structure, includes rotation axis joint subassembly, lower arm shaft joint subassembly, upper arm shaft joint subassembly, ball wrist joint subassembly, snatchs the manipulator subassembly, the rotation axis joint subassembly pass through steering wheel and axis of rotation with lower arm shaft joint subassembly transmission is connected, lower arm shaft joint subassembly pass through steering wheel and lower arm joint connecting rod with upper arm shaft joint subassembly transmission is connected, upper arm shaft joint subassembly pass through steering wheel and forearm joint connecting rod with ball wrist joint subassembly transmission is connected, ball wrist joint subassembly pass through the rudder frame with snatch the manipulator subassembly and can dismantle fixed connection, snatch the manipulator subassembly and utilize lead screw motor to carry out the centre gripping or put in.

Further, the rotation axis joint assembly comprises a first steering engine, an installation base, a first coupler and a horizontal rotation axis, a shell of the first steering engine is fixedly connected with the installation base in a detachable mode, a steering wheel of the first steering engine is connected with one end of the horizontal rotation axis in a transmission mode through the first coupler, the other end of the horizontal rotation axis is fixedly connected with the lower arm shaft joint assembly in a detachable mode, and the first steering engine can drive the lower arm shaft joint assembly to rotate.

Further, underarm axle joint subassembly includes underarm axle U type frame, cross axle, underarm joint connecting rod and sixth steering wheel, horizontal axis of rotation with fixed connection can be dismantled to the roof of underarm axle U type frame, can drive underarm axle U type frame rotates, the cross axle is located in the underarm axle U type frame, both ends respectively with underarm axle U type frame rotates to be connected, be provided with the pedestal on the cross axle, underarm joint connecting rod with fixed connection can be dismantled to the pedestal, the sixth steering wheel is located back the type frame, and passes through back the type frame with fixed connection can be dismantled to the lateral wall of underarm axle U type frame, the steering wheel of sixth steering wheel pass through the third shaft coupling with cross axle transmission is connected, drives underarm joint connecting rod rotates.

Further, the upper arm shaft joint component comprises a second steering engine, a third steering engine, a second steering engine frame, an upper arm shaft U-shaped frame and a small arm joint connecting rod, the second steering engine frame is fixedly connected with the lower arm joint connecting rod in a detachable mode, a steering wheel of the second steering engine is fixedly connected with a side wall of the upper arm shaft U-shaped frame in a detachable mode, the second steering engine drives the upper arm shaft U-shaped frame to rotate, a shell of the third steering engine is fixedly connected with a top wall of the upper arm shaft U-shaped frame in a detachable mode, the steering wheel of the third steering engine is connected with a second coupler, and one end of the small arm joint connecting rod is connected to the second coupler in a sleeved mode.

Furthermore, the ball wrist joint assembly comprises a fourth steering engine, a fifth steering engine, a fourth steering engine frame and a fifth steering engine frame, the fourth steering engine is arranged in the fourth steering engine frame, one side of the fourth steering engine frame is detachably and fixedly connected with the second coupler, the fifth steering engine is arranged in the fifth steering engine frame, and the fourth steering engine is connected with the fifth steering engine through an axle connecting block.

Further, a first upper baffle plate in a Z shape and a second upper baffle plate in a Z shape are fixed outside the fourth rudder rack, the first upper baffle plate and the second upper baffle plate are connected with a third upper baffle plate and a fourth upper baffle plate, the first upper baffle plate, the second upper baffle plate, the third upper baffle plate and the fourth upper baffle plate form a first accommodating cavity, a transmission shaft of the fourth steering engine is connected with a first belt pulley, the first belt pulley is connected with a second belt pulley through a first synchronous belt, the second belt pulley is arranged in the first accommodating cavity, and the second belt pulley is provided with a first transmission shaft. The fifth rudder frame is externally fixed with a first lower baffle plate in a Z shape and a second lower baffle plate in a Z shape, the first lower baffle plate and the second lower baffle plate are connected with a third lower baffle plate and a fourth lower baffle plate, the first lower baffle plate, the second lower baffle plate, the third lower baffle plate and the fourth lower baffle plate form a second containing cavity, the transmission shaft of the fifth steering engine is connected with a third belt pulley, the third belt pulley is connected with a fourth belt pulley through a second synchronous belt, the fourth belt pulley is arranged in the second containing cavity, and the fourth belt pulley is provided with a second transmission shaft. The first transmission shaft is connected with the second transmission shaft through the shaft connecting block.

Furthermore, the grabbing manipulator assembly comprises a screw motor, an outer frame, a first grabbing portion, a second grabbing portion, a connecting rod and a connecting rod group, one side of the outer frame is detachably and fixedly connected with the fifth steering engine frame, the screw motor is fixed in the outer frame, a screw of the screw motor faces the other side of the outer frame, a connecting plate is connected to the screw of the screw motor in a matched manner, and the connecting plate can move relative to the screw. The first grabbing part is hinged to the upper side of the outer frame through a first connecting shaft, one end of the connecting rod is hinged to the connecting plate through a second connecting shaft, and the other end of the connecting rod is hinged to the inner side of the first grabbing part through a third connecting shaft. The second grabbing part is hinged to the lower side of the outer frame through a fourth connecting shaft, one end of the connecting rod group is hinged to the connecting plate through a fifth connecting shaft, and the other end of the connecting rod group is hinged to the inner side of the second grabbing part through a sixth connecting shaft.

The beneficial effects of the utility model are that: the utility model discloses a structure design of personification, running state, position angle etc. are controlled through the steering wheel to each articular activity for control is more accurate, realizes moving about freely like people's upper limbs, so that better centre gripping or input article. The rotating shaft joint component can drive the upper arm shaft joint component to rotate for 360 degrees, and the lower arm shaft joint component can drive the joint connecting rod to rotate for 180 degrees so as to approximately simulate the moving state of a shoulder joint of a human body; the upper arm shaft joint assembly can drive the ball wrist joint assembly to mechanically rotate for 360 degrees so as to approximately simulate the moving state of the elbow joint of the human body; the ball wrist joint components can rotate by 100 degrees to approximately simulate the moving state of the human wrist joint; and multi-direction and multi-angle accurate clamping or throwing operation is realized through a plurality of steering engines.

Drawings

Fig. 1 is a schematic view illustrating a structural principle of an embodiment of the present invention.

Fig. 2 is a side view of fig. 1.

Fig. 3 is a schematic structural view of the rotary joint assembly and the lower arm joint assembly.

Fig. 4 is a side view of fig. 3.

Fig. 5 is a schematic structural view of the ball and wrist joint assembly.

Fig. 6 is a side view of fig. 5.

Figure 7 shows a grasping robot assembly.

Description of reference numerals: 1. a rotary shaft joint assembly; 2. a lower arm axis joint assembly; 3. an upper arm axis joint assembly; 4. a ball and wrist joint assembly; 5. grabbing the manipulator assembly; 6. a lower arm joint link; 7. a first steering engine; 8. a second steering engine; 9. a third steering engine; 10. a fourth steering engine; 11. a fifth steering engine; 12. a lead screw motor; 13. mounting a base; 14. a first grasping portion; 15. a second grasping portion; 16. a fourth rudder mount; 17. a first upper baffle; 18. a second upper baffle; 19. a first lower baffle; 20. a second lower baffle; 21. a first pulley; 22. a second pulley; 23. a first synchronization belt; 24. a fourth pulley; 25. a third belt pulley; 26. a second synchronous belt; 27. a third lower baffle; 28. a fifth rudder mount; 29. a shaft connecting block; 30. a third upper baffle; 31. a horizontal rotating shaft; 32. a first coupling; 33. a back-shaping frame; 34. a shaft bracket; 35. a horizontal axis; 36. a forearm joint link; 37. a second coupling; 38. a link rod group; 39. a connecting rod; 40. an outer frame; 41. a fourth upper baffle; 42. a lower arm shaft U-shaped frame; 43. a third coupling; 44. a sixth steering engine; 45. a second rudder mount; 46. an upper arm shaft U-shaped frame; 47. a first drive shaft; 48. a second drive shaft; 49. a first connecting shaft; 50. a second connecting shaft; 51. a fifth connecting shaft; 52. a sixth connecting shaft; 53. a fourth connecting shaft; 54. a third connecting shaft; 55. a fourth lower baffle; 56. a connecting plate.

Detailed Description

The utility model discloses a mechanical arm structure, it is right below with the accompanying drawing the utility model discloses an embodiment does the concrete description.

As shown in fig. 1 and 2, the robot comprises a rotating shaft joint assembly 1, a lower arm shaft joint assembly 2, an upper arm shaft joint assembly 3, a ball wrist joint assembly 4 and a grabbing robot assembly 5. The rotating shaft joint assembly 1 comprises a first steering engine 7, a mounting base 13, a first coupler 32 and a horizontal rotating shaft, a shell of the first steering engine 7 is detachably and fixedly connected with the mounting base 13, a steering wheel of the first steering engine 7 is located in the mounting base 13, and the steering wheel of the first steering engine 7 is in transmission connection with the rear end of the horizontal rotating shaft 31 through the first coupler 32.

Referring to fig. 3 and 4, the lower arm shaft joint assembly 2 includes a lower arm shaft U-shaped frame 42, a horizontal shaft 35, a lower arm joint connecting rod 6 and a sixth steering gear 44, and the front end of the horizontal rotating shaft 31 is detachably and fixedly connected to the top wall of the lower arm shaft U-shaped frame 42, so as to drive the lower arm shaft U-shaped frame 42 to rotate. The transverse shaft 35 is positioned in the lower arm shaft U-shaped frame 42, two ends of the transverse shaft 35 are respectively connected with the lower arm shaft U-shaped frame 42 in a rotating mode, the transverse shaft 35 is fixedly provided with a shaft frame 34, and the lower arm joint connecting rod 6 is detachably and fixedly connected with the shaft frame 34. The sixth steering engine 44 is located in the swage mount 33 and is detachably and fixedly connected with the side wall of the right side of the lower arm shaft U-shaped mount 42 through the swage mount 33. The rudder disc of the sixth steering engine 44 is in transmission connection with the cross shaft 35 through a third coupler 43, and can drive the lower arm joint connecting rod 6 to rotate.

Go up arm axle joint subassembly 3 and include second steering wheel 8, third steering wheel 9, second rudder frame 45, upper arm axle U type frame 46 and forearm joint connecting rod 36, second rudder frame 45 can dismantle fixed connection with underarm joint connecting rod 6, and second steering wheel 8 is fixed in second rudder frame 45. An upper arm shaft U-shaped frame 46 is arranged on the outer side of the front portion of the second steering engine 8, a steering wheel of the second steering engine 8 is detachably and fixedly connected with the right side of the upper arm shaft U-shaped frame 46, and the second steering engine 8 can drive the upper arm shaft U-shaped frame 46 to rotate. The shell of the third steering engine 9 is detachably and fixedly connected with the top wall of the upper arm shaft U-shaped frame 46, a rudder disc of the third steering engine 9 faces the front side, the rudder disc of the third steering engine 9 is connected with a second coupler 37, the front part of the small arm joint connecting rod 36 is bent and provided with a through hole matched with the second coupler 37, and the small arm joint connecting rod 36 is sleeved on the second coupler 37 through the through hole to support the second coupler 37.

Referring to fig. 5 and 6, ball and wrist joint assembly 4 includes a fourth steering engine 10, a fifth steering engine 11, a fourth rudder mount 16, and a fifth rudder mount 28. Fourth steering wheel 10 can be dismantled and fix in fourth rudder frame 16, fourth rudder frame 16's both sides can be dismantled respectively and be fixed with the first overhead gage 17 that is the Z style of calligraphy and the second overhead gage 18 that is the Z style of calligraphy, first overhead gage 17 and second overhead gage 18 are connected with third overhead gage 30 and fourth overhead gage 41, first overhead gage 17, second overhead gage 18, third overhead gage 30 and fourth overhead gage 41 form the first chamber that holds, the transmission shaft of fourth steering wheel 10 is connected with first band pulley 21, first band pulley 21 is connected with second band pulley 22 through first hold-in range 23, second band pulley 22 sets up at the first intracavity that holds, second band pulley 22 has first transmission shaft 47. The fifth steering engine 11 is arranged in a fifth steering engine frame 28, a first lower baffle 19 in a Z shape and a second lower baffle 20 in a Z shape are fixed outside the fifth steering engine frame 28, the first lower baffle 19 and the second lower baffle 20 are connected with a third lower baffle 27 and a fourth lower baffle 55, the first lower baffle 19, the second lower baffle 20, the third lower baffle 27 and the fourth lower baffle 55 form a second containing cavity, a transmission shaft of the fifth steering engine 11 is connected with a third belt wheel 25, the third belt wheel 25 is connected with a fourth belt wheel 24 through a second synchronous belt 26, the fourth belt wheel 24 is arranged in the second containing cavity, and the fourth belt wheel 24 is provided with a second transmission shaft 48. The first transmission shaft 47 of the second pulley 22 is connected to the second transmission shaft 48 of the fourth pulley 24 via the shaft connection block 29.

As shown in fig. 7, the grasping robot assembly 5 includes a screw motor 12, an outer frame 40, a first grasping portion 14, a second grasping portion 15, a connecting rod 39 and a connecting rod group 38, a rear portion of the outer frame 40 is detachably and fixedly connected with the fifth rudder mount 28, the screw motor 12 is detachably fixed in the outer frame 40, a screw of the screw motor 12 faces to the front side, a connecting plate 56 is connected to the screw of the screw motor 12 in a matching manner, and the connecting plate 56 can move back and forth relative to the screw. The first grasping portion 14 is hinged to the upper side of the outer frame 40 via a first connecting shaft 49, the connecting rod 39 is hinged at its rear end to a connecting plate 56 via a second connecting shaft 50, and at its front end to the inside of the first grasping portion 14 via a third connecting shaft 54. The second grasping portion 15 is hinged to the lower side of the outer frame 40 by a fourth connecting shaft 53, the rear end of the link rod group 38 is hinged to a connecting plate 56 by a fifth connecting shaft 51, and the front end is hinged to the inner side of the second grasping portion 15 by a sixth connecting shaft 52.

The utility model discloses an operation mode does: the steering wheel of the first steering engine 7 is in transmission connection with the top wall of a lower arm shaft U-shaped frame 42 in the lower arm joint assembly through a coupler and a horizontal rotating shaft, and the lower arm shaft U-shaped frame 42 can rotate 360 degrees relative to the first steering engine 7. The rudder disc of the sixth steering engine 44 is in transmission connection with the transverse shaft 35 in the lower arm shaft U-shaped frame 42 through the third coupler 43, so as to drive the lower arm joint connecting rod 6 to rotate, and the lower arm joint connecting rod 6 can rotate 180 degrees relative to the lower arm shaft U-shaped frame 42. The rudder disc of the second steering engine 8 drives the upper arm shaft U-shaped frame 46 to rotate, and the upper arm shaft U-shaped frame 46 can rotate 180 degrees relative to the second steering engine 8. The rudder disc of the third steering engine 9 is connected to the fourth rudder mount 16 via a second coupling 37, and the fourth rudder mount 16 can rotate 360 ° relative to the third steering engine 9. The first transmission shaft 47 in the ball wrist joint assembly 4 is connected with the second transmission shaft 48 through the shaft connecting block 29, and the fifth steering engine 11 can rotate 100 degrees relative to the fourth steering engine 10.

The utility model has the advantages that: the utility model discloses a structure design of personification, running state, position angle etc. are controlled through the steering wheel to each articular activity for control is more accurate, realizes moving about as people's upper limbs freely, so that better centre gripping or put in article. The rotating shaft joint component 1 can drive the upper arm shaft joint component 3 to rotate for 360 degrees, and the lower arm shaft joint component 2 can drive the lower arm joint connecting rod 6 to rotate for 180 degrees so as to approximately simulate the activity state of a human shoulder joint; the upper arm shaft joint component 3 can drive the ball wrist joint component 4 to mechanically rotate for 360 degrees so as to approximately simulate the moving state of the elbow joint of a human body; the ball wrist joint assembly 4 can rotate 100 degrees to approximately simulate the moving state of the human wrist joint; steering engines are arranged among the assemblies to increase power, and multi-direction and multi-angle accurate clamping or throwing operation can be achieved.

Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and the changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also belong to the protection scope of the present invention.

Claims

1. A robotic arm structure, characterized by: including rotation axis joint subassembly (1), lower arm axle joint subassembly (2), upper arm axle joint subassembly (3), ball wrist joint subassembly (4), snatch manipulator subassembly (5), rotation axis joint subassembly (1) through steering wheel and axis of rotation with lower arm axle joint subassembly (2) transmission is connected, lower arm axle joint subassembly (2) through steering wheel and lower arm joint connecting rod (6) with upper arm axle joint subassembly (3) transmission is connected, upper arm axle joint subassembly (3) through steering wheel and forearm joint connecting rod (36) with ball wrist joint subassembly (4) transmission is connected, ball wrist joint subassembly (4) through the rudder frame with snatch manipulator subassembly (5) and can dismantle fixed connection, it utilizes lead screw motor (12) to carry out the centre gripping or puts in manipulator subassembly (5).

2. A robot arm structure according to claim 1, wherein: the rotation axis joint assembly (1) comprises a first steering engine (7), a mounting base (13), a first coupler (32) and a horizontal rotation axis, a shell of the first steering engine (7) is fixedly connected with the mounting base (13) in a detachable mode, a rudder disc of the first steering engine (7) passes through the first coupler (32) and one end of the horizontal rotation axis is connected in a transmission mode, the other end of the horizontal rotation axis is fixedly connected with the lower arm axis joint assembly (2) in a detachable mode, and the first steering engine (7) can drive the lower arm axis joint assembly (2) to rotate.

3. A robot arm structure according to claim 2, wherein: lower arm axle joint subassembly (2) include lower arm axle U type frame (42), cross axle (35), lower arm joint connecting rod (6) and sixth steering wheel (44), horizontal axis of rotation (31) with fixed connection can be dismantled to the roof of lower arm axle U type frame (42), can drive lower arm axle U type frame (42) rotate, cross axle (35) are located in lower arm axle U type frame (42), both ends respectively with lower arm axle U type frame (42) rotate to be connected, be provided with on cross axle (35) pedestal (34), lower arm joint connecting rod (6) with fixed connection can be dismantled in pedestal (34), sixth steering wheel (44) are located returning type frame (33), and pass through returning type frame (33) with fixed connection can be dismantled to the lateral wall of lower arm axle U type frame (42), the steering wheel of sixth steering wheel (44) pass through third (43) with cross axle coupling (35) transmission is connected, drives lower arm joint connecting rod (6) rotate.

4. A robot arm structure according to claim 3, wherein: go up arm axle joint subassembly (3) and include second steering wheel (8), third steering wheel (9), second steering wheel frame (45), upper arm axle U type frame (46) and forearm joint connecting rod (36), second steering wheel frame (45) with fixed connection can be dismantled in lower arm joint connecting rod (6), second steering wheel (8) set up in second steering wheel frame (45), the steering wheel of second steering wheel (8) with fixed connection can be dismantled to the lateral wall of upper arm axle U type frame (46), second steering wheel (8) drive upper arm axle U type frame (46) rotate, the shell of third steering wheel (9) with fixed connection can be dismantled to the roof of upper arm axle U type frame (46), the steering wheel of third steering wheel (9) is connected with second shaft coupling (37), the one end of forearm joint connecting rod (36) cup joints on second shaft coupling (37).

5. A robot arm structure according to claim 4, wherein: the ball wrist joint assembly (4) comprises a fourth steering engine (10), a fifth steering engine (11), a fourth steering engine frame (16) and a fifth steering engine frame (28), the fourth steering engine (10) is arranged in the fourth steering engine frame (16), one side of the fourth steering engine frame (16) is detachably and fixedly connected with the second coupler (37), the fifth steering engine (11) is arranged in the fifth steering engine frame (28), and the fourth steering engine (10) is connected with the fifth steering engine (11) through a shaft connecting block (29).

6. A robot arm structure according to claim 5, wherein: a first upper baffle (17) in a Z shape and a second upper baffle (18) in a Z shape are fixed outside the fourth rudder rack (16), the first upper baffle (17) and the second upper baffle (18) are connected with a third upper baffle (30) and a fourth upper baffle (41), the first upper baffle (17), the second upper baffle (18), the third upper baffle (30) and the fourth upper baffle (41) form a first accommodating cavity, a transmission shaft of the fourth steering engine (10) is connected with a first belt wheel (21), the first belt wheel (21) is connected with a second belt wheel (22) through a first synchronous belt (23), the second belt wheel (22) is arranged in the first accommodating cavity, and the second belt wheel (22) is provided with a first transmission shaft (47);

a first lower baffle (19) in a Z shape and a second lower baffle (20) in a Z shape are fixed outside the fifth rudder rack (28), the first lower baffle (19) and the second lower baffle (20) are connected with a third lower baffle (27) and a fourth lower baffle (55), the first lower baffle (19), the second lower baffle (20), the third lower baffle (27) and the fourth lower baffle (55) form a second accommodating cavity, a transmission shaft of the fifth steering engine (11) is connected with a third belt wheel (25), the third belt wheel (25) is connected with a fourth belt wheel (24) through a second synchronous belt (26), the fourth belt wheel (24) is arranged in the second accommodating cavity, and the fourth belt wheel (24) is provided with a second transmission shaft (48);

the first transmission shaft (47) is connected with the second transmission shaft (48) through the shaft connecting block (29).

7. A robot arm structure according to claim 5, wherein: the grabbing manipulator assembly (5) comprises a lead screw motor (12), an outer frame (40), a first grabbing part (14), a second grabbing part (15), a connecting rod (39) and a connecting rod group (38), one side of the outer frame (40) is detachably and fixedly connected with the fifth rudder rack (28), the lead screw motor (12) is fixed in the outer frame (40), a lead screw of the lead screw motor (12) faces the other side of the outer frame (40), a connecting plate (56) is connected onto the lead screw of the lead screw motor (12) in a matched manner, and the connecting plate (56) can move relative to the lead screw;

the first grabbing part (14) is hinged with the upper side of the outer frame (40) through a first connecting shaft (49), one end of the connecting rod (39) is hinged with the connecting plate (56) through a second connecting shaft (50), and the other end of the connecting rod is hinged with the inner side of the first grabbing part (14) through a third connecting shaft (54);

the second grabbing part (15) is hinged with the lower side of the outer frame (40) through a fourth connecting shaft (53), one end of the connecting rod group (38) is hinged with the connecting plate (56) through a fifth connecting shaft (51), and the other end of the connecting rod group is hinged with the inner side of the second grabbing part (15) through a sixth connecting shaft (52).