TWI468599B - Three degree of freedom universal joint - Google Patents

Description

Three degrees of freedom universal joint

The invention relates to a universal joint, in particular to a three-degree-of-freedom universal joint.

Universal joints generally have only two degrees of freedom, and in some complex multi-degree-of-freedom motion mechanisms, such as parallel six-axis robots, the universal joint is required to have three degrees of freedom to achieve its motion, otherwise it will be operated at the time of operation. The knot will be stuck, which will cause damage to the entire parallel six-axis robot. In addition, the conventional universal joint structure is relatively complicated, the volume is relatively bulky, and the movement flexibility is relatively low.

In view of the above situation, it is necessary to provide a three-degree-of-freedom universal joint with simple structure and high flexibility of movement.

A three-degree-of-freedom universal joint includes a first connecting seat, a second connecting seat and a two-way hinge, wherein the first connecting seat and the second connecting seat are perpendicular to the first axis direction and the second by the two-way hinge The axial direction is rotatably mounted together, the three-degree-of-freedom universal joint further includes a third connecting seat, the third connecting base includes a seat body, a rotating shaft and a tapered roller bearing, the seat body includes a mounting end and a a connecting end opposite to the mounting end; the tapered roller bearing is rotatably sleeved on the rotating shaft and mounted in the housing along the rotating shaft, and one end of the rotating shaft protrudes from the mounting end and is fixed to the shaft The second connecting seat is configured to rotate the seat body in a third axis direction perpendicular to the first axis direction and the second axis direction.

The above-mentioned degree of freedom universal joint has a simple structure, low cost, and high practicability, and is widely applied to a mechanism or device that requires a plurality of degrees of freedom. By adding the third connecting seat, the three-degree-of-free joint can be freely rotated about three axial directions perpendicular to each other, which greatly improves the movement flexibility of the mechanism, device and the like to which the three-degree-of-free joint is applied.

100‧‧‧Three Degrees of Freedom Universal Joint

10‧‧‧First connector

11‧‧‧ base

13, 23‧‧‧ hinge block

132, 232‧‧‧ hinged holes

20‧‧‧Second connector

21‧‧‧Substrate

211‧‧‧Installation top surface

212‧‧‧Assembled bottom

213‧‧‧Assemble

215, 8115‧‧‧ fixing holes

30‧‧‧Two-way hinge

31, 32‧‧‧ side

313, 323‧‧‧ shaft hole

40‧‧‧ articulated shaft

50‧‧‧ Connection pin

51‧‧‧ Pin body

53‧‧‧ head

55‧‧‧stopping

60‧‧‧ pin

61‧‧‧ pinhole

70, 88‧‧‧ screws

80‧‧‧ third connector

81‧‧‧ body

811‧‧‧Assembly

812‧‧‧Connected end

813‧‧‧ stepped hole

8131‧‧‧Assembly Department

8132‧‧‧Regulatory Department

8135‧‧‧Responsible Department

83‧‧‧ shaft

831‧‧‧Spindle Department

8315‧‧‧Fixed holes

833‧‧‧Connecting Department

835‧‧‧Adjustment shaft

85‧‧‧Tapered roller bearings

87‧‧‧ bearing gland

871‧‧‧ Pressing surface

873‧‧‧ outer surface

874‧‧‧Installation Department

875‧‧‧Fixed holes

876‧‧‧ shaft hole

878‧‧‧Resist the ring

89‧‧‧ thrust pin bearings

1 is a schematic perspective view of a three-degree-of-freedom joint of a preferred embodiment of the present invention.

2 is a perspective exploded view of the three-degree-of-freedom universal joint shown in FIG. 1.

3 is a perspective exploded view of the three-degree-of-freedom universal joint shown in FIG. 1 from another perspective.

Figure 4 is a cross-sectional view of the three-degree-of-freedom universal joint shown in Figure 1 taken along line IV-IV.

FIG. 5 is a perspective exploded view of a three-degree-of-freedom universal joint rotary seat according to a preferred embodiment of the present invention.

6 is a perspective exploded view of the rotary seat of the three-degree-of-freedom universal joint according to the preferred embodiment of the present invention.

The three-degree-of-freedom universal joint of the invention can be widely applied to various complex multi-degree-of-freedom motion mechanisms to improve the movement flexibility of the mechanism, device and the like using the three-degree-of-freedom universal joint. The three-degree-of-freedom universal joint of the preferred embodiment of the present invention is further applied to a parallel six-axis robot (not shown) as an example for further detailed description with reference to the accompanying drawings and specific embodiments.

Referring to FIG. 1 , a three-degree-of-freedom universal joint 100 according to a preferred embodiment of the present invention includes a first connecting base 10 , a second connecting base 20 , a two-way hinge 30 , two hinge shafts 40 , a connecting pin 50 , a pin 60 , and The third connector 80. The first connector 10 and the second connector 20 are The two-way hinge 30, the two hinge shafts 40, the connecting pin 50 and the rotating pin shaft 60 are along two mutually perpendicular first axis directions (ie, the first degree of freedom X-axis direction shown in FIG. 1) and the second axis direction (also That is, the second degree of freedom Y-axis direction shown in Fig. 1 is rotatably mounted together. The third connecting base 80 and the second connecting base 20 are rotatably mounted along a third axis direction perpendicular to the first axis direction and the second axis direction (ie, the third degree of freedom Z axis direction shown in FIG. 1 ) Together.

Referring to FIG. 2 and FIG. 3 together, the first connecting base 10 has a substantially 'ㄇ' shape in cross section, and includes a base body 11 and two hinge blocks 13 protrudingly spaced apart from the base body 11. The ends of the two hinge blocks 13 respectively open through a hinge hole 132, and the hinge holes 132 of the two hinge blocks 13 are located on the same axis.

The structure of the second connecting base 20 is substantially equivalent to the structure of the first connecting base 10, and includes a base plate 21 and two hinge blocks 23 protruding from the base plate 21. The substrate 21 has a rectangular plate shape and includes a mounting top surface 211 and an assembly bottom surface 212 opposite to the mounting top surface 211. A substantially cylindrical mounting groove 213 is recessed toward the mounting bottom surface 212 at a substantially central position on the mounting top surface 211 of the substrate 21. Correspondingly, two fixing holes 215 are formed through the bottom of the mounting groove 213 so as to be adjacent to the mounting bottom surface 212 of the substrate 21 . The two hinge blocks 23 are oppositely disposed on the mounting bottom surface 212 of the substrate 21 and adjacent to the middle of the two side edges of the substrate 21. The two hinge blocks 23 are opposite to the two sides of the two fixing holes 215, and each of the hinge blocks 23 is adjacent to the hinge block 23 A hinge hole 232 is defined in the end position toward the other hinge block 23, and the two hinge holes 232 are coaxially disposed. The distance between the two hinge blocks 23 is equivalent to the distance between the two hinge blocks 13 of the first connector 10. When the two hinge blocks 13 of the first connecting base 10 and the two hinge blocks 23 of the second connecting base 20 are assembled together, the two hinge blocks 13 of the first connecting seat 10 and the two hinge blocks 23 of the second connecting seat 20 surround each other. a substantially rectangular mounting space (not shown) to provide a two-way hinge The connector 30 is installed in the installation space.

The two-way hinge 30 is substantially rectangular in shape in the embodiment, and is disposed in a mounting space surrounded by two hinge blocks 13 of the first connecting base 10 and two hinge blocks 23 of the second connecting base 20 to The first connecting base 10 and the second connecting base 20 are rotatably mounted along two mutually perpendicular degrees of freedom. A shaft hole 313, 323 is defined in each of the two opposite sides 31, 32 of the two-way hinge 30, and correspondingly, a two-way hinge 30 is formed in the two-way hinge 30. A cross hole with four sides connected to each other (not shown). The diameter of the shaft holes 313, 323 is equivalent to the hinge hole 132 of the first connector 10 and the hinge hole 232 of the second connector 20.

The two hinge shafts 40 are two hollow short shafts, and a connecting inner hole (not shown) is formed in the axial direction. One end of the two hinge shafts 40 are respectively fixed in the hinge holes 132 of the two hinge blocks 13 of the first connecting base 10, and the other ends are respectively rotatably mounted in the two ends of the shaft hole 313 of the two-way hinge 30, The first connector 10 and the two-way hinge 30 are rotatably mounted together.

The connecting pin 50 has a substantially T-shaped shaft shape and includes a substantially cylindrical shaft-shaped pin body 51 and a head portion 53 provided at one end of the pin body 51 having a larger cross-sectional diameter than the pin body 51. The diameter of the pin body 51 is equivalent to the diameter of the connecting inner hole of the hinge shaft 40, and the length of the pin body 51 is slightly larger than the sum of the lengths of the two hinge shafts 40 and the shaft holes 313 of the two-way hinge member 30. A stopper hole 55 is formed through the other end of the pin body 51 opposite to the head portion 53.

The pin shaft 60 is a long shaft, and a pin hole 61 is formed through the corresponding connecting pin 50 at a substantially central position. The pin shaft 60 is assembled through the shaft hole 323 of the two-way hinge member 30. The two ends of the pin shaft 60 are respectively mounted on the pin shaft 60. The second connecting seat 20 is in the hinge hole 232 of the hinge block 23.

Referring to FIG. 5 and FIG. 6 together, the third connecting base 80 includes a seat 81 and an adjusting nut 82. The rotating shaft 83, the tapered roller bearing 85, the bearing gland 87 and the thrust needle bearing 89 have a hollow rectangular cylindrical shape, and include a mounting end 811 and a connecting end 812 opposite to the mounting end 811. A fixing hole 8115 is recessed in the end surface of the mounting end 811 adjacent to the four corners of the periphery thereof. The inside of the seat body 81 is penetrated in the axial direction and forms a stepped inner hole 813 whose hole diameter is gradually reduced from the fitting end 811 toward the connecting end 812. The stepped inner hole 813 includes a shaft-shaped mounting portion 8131 recessed in the mounting end 811 and a shaft-shaped adjusting portion 8132 recessed toward the connecting end 812. The mounting portion 8131 is opposite to the adjusting portion 8132. A resisting portion 8135 is formed at the joint position (see FIG. 4).

The rotating shaft 83 is rotatably mounted by the tapered roller bearing 85 and received in the stepped inner hole 813 of the base 81. The rotating shaft 83 includes a main shaft portion 831, a connecting portion 833 and an adjusting shaft portion 835, a main shaft portion 831 and an adjustment. The shaft portion 835 is opposite to both ends of the connecting portion 833, and the shaft diameter is larger than the shaft diameter of the connecting portion 833. Two fixing holes 315 are defined in the two fixing holes 215 of the base plate 21 corresponding to the second connecting base 20 on the end surface of the main shaft portion 831 away from the adjusting shaft portion 835, so as to be the main shaft portion 831 of the rotating shaft 83. The two connecting seats 20 are fixed together. The outer peripheral wall of the adjustment shaft portion 835 is provided with a thread to be screwed together with the adjustment nut 82.

The tapered roller bearing 85 is sleeved on the main shaft portion 831 of the rotating shaft 83, and is mounted in the seat body 81 along with the rotating shaft 83. When assembled, the outer peripheral wall of the tapered roller bearing 85 is correspondingly fixed to the fitting portion of the seat body 81. On the inner wall of the 8131, the tapered roller bearing 85 abuts against the abutting portion 8135 toward the periphery of one end of the connecting end 812.

The bearing gland 87 is disposed on the mounting end 811 of the base 81. The tapered roller bearing 85 is received in the mounting portion 8131 of the base 81 and interposed between the bearing gland 87 and the abutting portion 8135. The bearing gland 87 has a substantially rectangular plate shape, and its peripheral size and the peripheral dimension of the seat body 81 Therefore, the bearing gland 87 can be completely fixedly mounted on the mounting end 811 of the base 81. A fixing hole 875 is defined in each of the four fixing holes 8115 of the corresponding bearing body 81 at a position corresponding to the four corners of the bearing gland 87. The bearing gland 87 includes a pressing surface 871 and an outer surface 873 opposite to the pressing surface 871. The outer surface 873 is recessed toward the pressing surface 871 to form a cylindrical mounting portion 874. A shaft hole 876 is defined in the direction of the pressing surface 871 so as to extend from the shaft hole 876 to be fixed to the second connecting seat 20 . A cylindrical resisting ring 878 is protruded from the pressing hole 871 around the shaft hole 876. The outer diameter of the resisting ring 878 is equal to the inner diameter of the fitting portion 8131 of the fitting end 811 of the seat body 81.

The thrust needle bearing 89 is disposed in the mounting portion 874 of the bearing gland 87 and is sleeved on the main shaft portion 831 of the rotating shaft 83 adjacent to the end position thereof.

Referring to FIG. 4 together, when the third connecting base 80 is assembled, the adjusting nut 82 is screwed onto the adjusting shaft portion 835 of the rotating shaft 83, and then the tapered roller bearing 85 is sleeved on the main shaft of the rotating shaft 83. The portion 831 is extended from the fitting end 811 of the seat body 81 along with the rotating shaft 83 and the adjusting nut 82 until the tapered roller bearing 85 is completely received in the fitting portion 8131 of the seat body 81. The tapered roller bearing 85 is abutted against the adjusting nut 82 toward one end of the adjusting nut 82. Correspondingly, the adjusting nut 82 is received in the adjusting portion 8132 along with the adjusting shaft portion 835 of the rotating shaft 83. The tapered roller bearing 85 faces the adjusting nut 82. One of the end faces abuts against the abutting portion 8135 of the stepped inner hole 813. Next, the bearing gland 87 is placed on the mounting end 811 of the seat body 81, and the bearing gland 87 and the seat body 81 are fixed by the four screws 88 passing through the fixing holes 875 of the bearing gland 87. Connected together. The end of the main shaft portion 831 of the rotating shaft 83 is exposed through the shaft hole 876 of the bearing gland 87. The abutting ring 878 of the bearing gland 87 is tightly fitted to the mounting end 811 of the seat body 81. Inside the mounting portion 8131. The abutting ring 878 is abutted against the tapered roller bearing 85, and the tapered roller bearing 85 is interposed between the bearing gland 87 and the abutting portion 8135. Finally, the thrust needle bearing 89 is mounted in the mounting portion 874 of the bearing gland 87 and sleeved on the end of the main shaft portion 831 of the rotating shaft 83, that is, the assembly of the third connecting seat 80 is completed.

When assembling the three-degree-of-freedom universal joint 100, the two screws 70 are first passed through the two fixing holes 215 of the base plate 21 of the second connecting base 20, and correspondingly fixed to the ends of the main shaft portion 831 of the rotating shaft 83. The hole 8315 is fixed to the end of the rotating shaft 83 of the third connecting seat 80. Next, the two-way hinge 30 is placed between the two hinge blocks 23 of the second connecting base 20, and the pin 60 is sequentially passed through the hinge hole 232 of the hinge block 23, the shaft hole 323 of the two-way hinge 30, and The hinge hole 232 of the other hinge block 23 is disposed at two ends of the pin 60 in the hinge hole 232 of the hinge block 23 of the second connector 20, and the pin hole 61 in the middle of the pin 60 is bidirectional The shaft holes 313 of the hinge 30 are aligned and located on the same axis. Next, the two hinge blocks 13 of the first connector 10 are aligned on both sides of the two-way hinge 30, and the hinge holes 132 on the hinge block 13 are aligned with the shaft holes 313 of the two-way hinge 30, The two hinge shafts 40 respectively pass through the hinge holes 132 of the two hinge blocks 13 and are hinged to opposite ends of the shaft hole 313 of the two-way hinge member 30. Finally, the pin body 51 of the connecting pin 50 is sequentially passed through an hinge shaft 40, one end of the shaft hole 313 of the two-way hinge 30, the pin hole 61 in the middle of the pin shaft 60, and protrudes from the other end of the shaft hole 313, and finally wears. Passing through another hinge shaft 40, and preventing the connecting pin 50 from coming out through a stopper hole 55 provided at the end of the connecting pin 50 by a stopper bolt (not shown), that is, completing the three-degree-of-freedom joint 100 installation.

Referring again to FIG. 1 , when the three-degree-of-freedom joint 100 is used, the first connector 10 is rotatably mounted by the two-way hinge 30 and the second connector 20, wherein the first connector 10 relative to the second connecting seat 20 can be around the first axis (ie, the X axis shown in Figure 1) And the second axis (ie, the Y axis shown in FIG. 1) rotates in two degrees of freedom. The third connecting seat 80 is rotatably mounted relative to the second connecting base 20 about the third axis (ie, the Z axis shown in FIG. 1) perpendicular to the plane of the X-axis and the Y-axis.

The three-degree-of-freedom universal joint 100 has a simple structure, low cost, and high practicability, and is widely applied to a mechanism or device that requires a plurality of degrees of freedom. By adding a third connector 80, the three-degree-of-free joint 100 can be wound around a first axis (ie, the X-axis shown in FIG. 1), a second axis (ie, the Y-axis shown in FIG. 1), and a third axis ( That is, the Z-axis of FIG. 1 is freely rotated by three degrees of freedom, which greatly improves the flexibility of the mechanism, device, and the like to which the three-degree-of-freedom universal joint 100 is applied. The three-degree-of-freedom universal joint 100 is greatly enhanced by the combination of a highly rigid tapered roller bearing 85 and a thrust needle bearing 89, which greatly enhances the third degree of freedom of the three-degree-of-freedom universal joint 100 around the Z-axis. The rotation performance, and the locking nut 82 can adjust and control the gap between the tapered roller bearing 85 relative to the inner wall of the seat 81 and the bearing gland 87 when the third connecting seat 80 rotates, thereby improving the three-degree-of-freedom universal joint 100 rotation accuracy.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

100‧‧‧Three Degrees of Freedom Universal Joint

10‧‧‧First connector

20‧‧‧Second connector

30‧‧‧Two-way hinge

40‧‧‧ articulated shaft

50‧‧‧ Connection pin

60‧‧‧ pin

80‧‧‧ third connector

Claims (10)

A three-degree-of-freedom universal joint includes a first connecting seat, a second connecting seat and a two-way hinge, wherein the first connecting seat and the second connecting seat are perpendicular to the first axis direction and the second by the two-way hinge The shaft direction is rotatably mounted together, and the improvement is that the three-degree-of-freedom universal joint further includes a third connecting seat, the third connecting base includes a seat body, a rotating shaft and a tapered roller bearing, and the seat body includes a a mounting end and a connecting end opposite to the mounting end; the tapered roller bearing is rotatably sleeved on the rotating shaft and mounted in the housing along with the rotating shaft, and one end of the rotating shaft protrudes from the mounting end and is fixed Connected to the second connecting base to rotate the base body in a third axial direction perpendicular to the first axial direction and the second axial direction. For example, the three-degree-of-freedom universal joint described in claim 1 wherein the seat body has a hollow cylindrical shape. The three-degree-of-freedom universal joint according to claim 1, wherein the body is penetrated in the axial direction and forms a stepped inner hole whose hole diameter is gradually reduced from the fitting end toward the connecting end direction, the step inner hole The utility model comprises a mounting portion recessed in the mounting end, an adjusting portion recessed toward the connecting end, and an abutting portion formed at a position where the fitting portion meets the adjusting portion; the third connecting seat further comprises a bearing gland, The bearing gland cover is disposed at the mounting end of the seat body, and the tapered roller bearing is received in the mounting portion of the seat body and is interposed between the bearing gland and the abutting portion. The three-degree-of-freedom universal joint according to claim 3, wherein the rotating shaft comprises a main shaft portion, a connecting portion and an adjusting shaft portion, and the main shaft portion and the adjusting shaft portion are oppositely located at opposite ends of the connecting portion, the adjusting shaft The outer peripheral wall of the portion is provided with a thread; the tapered roller bearing is rotatably sleeved on the main shaft portion, and the outer peripheral wall of the tapered roller bearing is correspondingly abutted against the inner wall of the fitting portion of the seat body, and is oriented toward one end of the adjusting shaft portion The peripheral edge corresponds to the abutting portion; the third connecting seat further includes an adjusting nut screwed onto the adjusting shaft portion and abutting against the tapered roller bearing. The three-degree-of-freedom universal joint according to claim 3 or 4, wherein the bearing gland comprises a pressing surface and an outer surface opposite to the pressing surface, the pressing surface correspondingly pressing against the a cylindrical mounting portion is formed on the outer surface of the mounting body toward the pressing surface, and a shaft hole is formed in the middle of the mounting portion; the end of the main shaft portion of the rotating shaft protrudes from the shaft hole and is fixed Connected to the second connecting seat, the third connecting base further includes a thrust needle bearing, and the thrust needle bearing is disposed in the mounting portion of the bearing gland and sleeved on the main shaft portion of the rotating shaft At the end position. The three-degree-of-freedom universal joint according to claim 5, wherein the pressing surface has a cylindrical abutting ring protruding around the shaft hole, and the outer diameter of the resisting ring is the same as The inner diameter of the mounting portion of the mounting end of the seat body is equivalent; the resisting ring is tightly fitted in the fitting portion of the seat body and abuts against the tapered roller bearing, and the tapered roller bearing is clamped to the bearing Between the gland and the abutment. The three-degree-of-freedom universal joint according to claim 5, wherein a fixing hole is respectively recessed on the end surface of the mounting end adjacent to the four corners of the periphery thereof, and the bearing gland is adjacent to the four corners of the periphery thereof. A fixing hole is formed through the four fixing holes, and the bearing gland is fixedly mounted on the mounting end of the base body by four screws. The three-degree-of-freedom universal joint according to claim 5, wherein the second connecting base comprises a substrate and two hinge blocks protrudingly on the substrate, and a mounting groove is recessed on the substrate, and the spindle portion of the rotating shaft The end is installed in the mounting groove of the substrate, and is fixedly mounted with the second connecting base. The three-degree-of-freedom universal joint according to claim 8, wherein the first connecting base comprises a base body and two spaced apart hinge blocks protruding from the base body, the first connecting seat and the second connecting end. A hinge hole is defined in each of the two upper hinge blocks; the two hinge blocks of the first connector are assembled with the two hinge blocks of the second connector, and the two-way hinge is received in the four hinges. a space enclosed by the block and connecting the first connector to the second connector The seat is rotatably hinged together along two mutually perpendicular first and second axes of freedom. The three-degree-of-freedom universal joint according to claim 9, wherein the two adjacent sides of the two-way hinge are respectively provided with a shaft hole, and a bidirectional hinge is formed in the two-way hinge. The three-sided universal joint further comprises two hinge shafts and a pin shaft; the pin shaft passes through the shaft hole of the two-way hinge member, and the two ends are respectively fixedly mounted on the second joint seat The two hinged shafts are oppositely disposed at opposite ends of the other axial hole of the two-way hinge, and are respectively hinged in the hinge holes of the two hinge blocks of the first connecting seat.