TWI898365B - Pinless universal joint device - Google Patents

Abstract

A pinless universal joint device comprises a cartridge seat, a joint assembly and a positioning member. The cartridge seat has an inner wall surface surrounding and defining a receiving groove. The inner wall surface has two protrusions and two arc-shaped portions. Each of the protrusions has two first latching surfaces. The joint assembly is rotatably connected to the cartridge seat and includes a rotating head. The outer surface of the rotating head has two spherical portions and two second latching surfaces. The second latching surfaces are respectively used to latch on to the protrusions. The curvature of each spherical portion on a radial cross section perpendicular to the axis is greater than 90 degrees and less than 140 degrees. The positioning member is arranged on the cartridge seat and is used to block the rotating head so that the joint assembly is confined in the cartridge seat. The present invention does not require drilling on the rotating head, is simpler to process, can reduce manufacturing costs, and is more durable.

Description

Pinless universal joint device

The present invention relates to a tool head, and more particularly to a pinless universal joint device.

Referring to FIG. 1 , a conventional universal joint includes a socket 11, a ball-end swing member 12 rotatably mounted within the socket 11, a pin 13 extending through the socket 11 and the ball-end swing member 12, and an outer cylinder 14 sleeved on the outer side of the socket 11. The socket 11 is provided with two opposing transverse through-holes 111. The ball-end swing member 12 has a pivot hole 121 extending through two opposite sides and aligned with the transverse through-holes 111. By extending the pin 13 through the transverse through-holes 111 and the pivot hole 121, the ball-end swing member 12 can swing relative to the pin 13 and is rigidly connected to the socket 11 at an angle to transmit torque.

Although this universal joint can be used to transmit torque, it requires not only machining a spherical outer profile on the ball-end swing member 12 but also multiple drilling operations to form the pivot hole 121. The outer cylinder 14 is then installed to prevent the pin 13 from dislodging from the socket 11. This universal joint has many parts and is complex to machine, resulting in high manufacturing costs. Furthermore, when transmitting torque, the universal joint only engages at the junction between the pin 13 and the transverse through-holes 111, leaving a small contact area and making it less durable.

Therefore, the object of the present invention is to provide a pinless universal joint device that can reduce manufacturing costs and is more durable.

Therefore, the pinless universal joint device of the present invention includes a cartridge seat, a joint assembly and a positioning member. The cartridge seat includes a driven portion and a receiving groove opposite to the driven portion in a height direction. The cartridge seat has an inner wall surface surrounding an axis parallel to the height direction and defining the receiving groove. The inner wall surface has two convex portions arranged oppositely in the radial direction, and two arc-shaped portions arranged oppositely in the radial direction. The two opposite sides of each of the convex portions are respectively connected to the arc-shaped portions. The two opposite sides of each of the arc-shaped portions are respectively connected to the convex portions. Each of the convex portions protrudes in the direction of the axis and has two oppositely inclined first latching surfaces, and the first latching surfaces of the convex portions and the arc-shaped portions together define two movable spaces spaced opposite to each other.

The connector assembly is rotatably connected to the cartridge seat, and the connector assembly includes a rotating head and a tool portion. The rotating head is rotatably arranged in the receiving groove of the cartridge seat, and the outer surface of the rotating head has two spherical portions respectively accommodated in the movable spaces, and two second latching portions connected to the spherical portions. The second latching portions are respectively used to latch on to the protrusions. Each of the spherical portions is connected to the second latching portions. The two opposite sides of each of the second latching portions are respectively connected to the spherical portions. The curvature of each of the spherical portions on a radial cross section perpendicular to the axis is greater than 90 degrees and less than 140 degrees. The tool portion is connected to the rotating head and extends beyond the cartridge seat in the height direction. The positioning member is arranged on the cartridge seat and is used to block the rotating head so that the connector assembly is confined in the cartridge seat.

The present invention is effective in that torque is transmitted by engaging the second latching surfaces of the connector assembly with the protrusions of the cartridge seat. This eliminates the need for drilling holes in the rotary head and the need for additional latching components. Furthermore, the two spherical surfaces and the two second latching surfaces are formed on the rotary head with relatively simple processing, thereby reducing manufacturing costs. Furthermore, the contact area between the second latching surfaces and the protrusions is relatively large, making the present invention more durable.

2 to 4 , a first embodiment of the pinless universal joint device of the present invention includes a cartridge seat 2 , a joint assembly 3 , an elastic member 4 , and a positioning member 5 .

The cartridge holder 2 includes a driven portion 201, a circular receiving groove 202 that is opposite to the driven portion 201 in a height direction Z, and a stepped groove 203 that extends from the receiving groove 202 to the driven portion 201. In this embodiment, the driven portion 201 is a rectangular engagement hole. In some embodiments, the driven portion 201 may be a non-circular rod. The stepped groove 203 has a large-diameter section 204 connected to the bottom end of the receiving groove 202, and a small-diameter section 205 that extends from the large-diameter section 204 to the driven portion 201. The diameter of the large-diameter section 204 is larger than that of the small-diameter section 205.

Referring to Figures 3 to 5 , the axial cross-section depicted in Figure 3 is taken along line III-III in Figure 2 . The radial cross-section depicted in Figure 5 is taken along line V-V in Figure 3 . The cartridge holder 2 has an inner wall surface 21 that surrounds an axis L parallel to the height direction Z and defines the accommodating groove 202 . The inner wall surface 21 has two radially opposed protrusions 211, two radially opposed arcuate portions 212, and an annular groove 215 that circumferentially surrounds the axis L and is higher than the protrusions 211 and the arcuate portions 212. Opposite sides of each protrusion 211 are connected to the arcuate portions 212, respectively. Two opposite sides of each arc portion 212 are respectively connected to the protrusions 211 .

Each protrusion 211 protrudes toward the axis L and has two oppositely inclined first latching surfaces 213. The first latching surfaces 213 of the protrusions 211 and the arcuate portions 212 together define two spaced apart movable spaces 210. The tilt angle T1 of each first latching surface 213 ranges from 3 to 10 degrees.

The connector assembly 3 is rotatably connected to the cartridge holder 2 to swing relative to the axis L and adjust the connection angle between the connector assembly 3 and the cartridge holder 2. The connector assembly 3 includes a rotating head 31 and a tool portion 32. The rotating head 31 is rotatably disposed within the receiving groove 202 of the cartridge holder 2 and has a main body 311 and a connecting section 312 connecting the main body 311 and the tool portion 32.

Referring to Figures 4 to 6 , the main body 311 has two spherical portions 313, each housed within the movable spaces 210; two second latching portions 314 connected to the spherical portions 313; and two upper sector-shaped portions 315 connected to the upper sides of the second latching portions 314. The periphery of each spherical portion 313 is connected to the second latching portions 314, and the top edge of each spherical portion 313 extends to the connecting section 312. Opposite sides of each second latching portion 314 are connected to the spherical portions 313. The second latching portions 314 face and engage with the protrusions 211. The upper sector-shaped portions 315 are spaced parallel to each other and each has a fan-shaped bottom with a flattened bottom and an arc-shaped longitudinal side extending to the connecting section 312. Each second latching surface 314 is capable of horizontally rotating within the corresponding movable space 210, and each second latching surface 314 engages the corresponding protrusion 211 to transmit torque. Because the tilt angle T1 of each first latching surface 213 of this embodiment is between 3 degrees and 10 degrees, the rotating head 31 of the connector assembly 3 rotates smoothly within the cartridge base 2.

Referring to Figures 5, 7, and 8, the arc A1 of each spherical portion 313 on a radial cross-section perpendicular to the axis L is greater than 90 degrees and less than 140 degrees. When the arc A1 is less than 90 degrees, the area of the spherical portions 313 will become smaller, and the area of the second latching portions 314 will become larger, thereby reducing the smooth rotation of the rotating head 31. When the arc A1 is greater than 140 degrees, the area of the spherical portions 313 will become larger, and the area of the second latching portions 314 will become smaller, thereby affecting the latching effect. The arc A1 of this embodiment is 110 degrees. Specifically, as shown in Figures 7 and 8, the lower sides of the second latching portions 314 are connected and are roughly cylindrical. The spherical radius of each spherical portion 313 is r1, and the cylindrical radius of each second latching portion 314 is r2. The spherical radius r1 of each spherical portion 313 is larger than the cylindrical radius r2 of each second latching portion 314.

3 and 9 , when manufacturing the connector assembly 3 , a cutting machine (not shown) can be used to directly cut out the upper sector-shaped portions 315 and the second latching portions 314 on a sphere with a spherical radius r1 , thereby forming the spherical portions 313 . This simplifies the manufacturing process and reduces manufacturing costs.

Referring to Figures 3, 5, and 6, in this embodiment, the maximum length D1 of each upper sector-shaped surface portion 315 in a first direction X perpendicular to the height direction Z is equal to the length D2 of each second latching surface portion 314 in the first direction X, thereby simplifying manufacturing. The maximum length D3 of each upper sector-shaped surface portion 315 in the first direction X perpendicular to the first direction X is greater than or equal to the spherical radius r1 minus the cylindrical radius r2. The distance D4 from the vertex of each spherical surface portion 313 in the first direction X to the side edge of the corresponding second latching surface portion 314 is spherical radius r1. The ratio of this distance D4 to the spherical radius r1 is between 1:2 and 1:3, and the ratio of this distance D4 to the length D2 is between 1:2 and 1:3. The length D2 of each second latching surface portion 314 in the first direction X is approximately equal to the spherical radius r1 of each spherical surface portion 313. Optimal rotation and latching effects can be achieved through the above-mentioned size restriction.

3 and 4 , the tool portion 32 is connected to the rotary head 31 and extends beyond the cartridge seat 2 in the height direction Z. In this embodiment, the tool portion 32 is a ball bearing square head adapter. In some embodiments, the tool portion 32 may be a socket, a screwdriver, or other tool head.

The elastic member 4 is mounted within the stepped groove 203 of the cartridge holder 2 and can be compressively elastically pressed between the rotary head 31 and the cartridge holder 2. In this embodiment, the elastic member 4 is a wave spring. In some embodiments, the elastic member 4 can be a pyramidal spring or other compressible elastic element. In some embodiments, the pinless universal joint device does not include the elastic member 4.

The positioning member 5 is disposed on the cartridge seat 2 and is used to block the rotating head 31, thereby retaining the connector assembly 3 within the cartridge seat 2. In this embodiment, the positioning member 5 is a C-shaped buckle that is embedded in the annular groove 215 of the cartridge seat 2. In some embodiments, the positioning member 5 is a plurality of metal beads disposed on the cartridge seat 2 and protruding toward the rotating head 31, which can also achieve the same function of preventing the connector assembly 3 from being removed from the cartridge seat 2.

As shown in FIG10 , the connector assembly 3 can be rotated forward, backward, left, and right to change the connection angle between the connector assembly 3 and the cartridge holder 2 .

As shown in Figure 11, when using this embodiment, the connector assembly 3 and the cartridge holder 2 rotate relative to each other until each second latching surface 314 latches onto the corresponding protrusion 211, forming a rigid connection between the connector assembly 3 and the cartridge holder 2 and enabling continuous torque transmission. Compared to conventional latching methods that utilize contact between a pin and a hole, the second latching surfaces 314 of the present invention contact the protrusions 211 over a larger area. As a result, the latching area between the rotating head 31 and the cartridge holder 2 is larger, resulting in greater durability and a longer service life.

12 to 14 , a second embodiment of the present invention is similar to the first embodiment, except that:

The rotating head 31 also has two lower fan-shaped surfaces 316 (due to the angle, only one can be seen in the figure) that are respectively connected to the lower sides of the second latching surfaces 314. Each of the lower fan-shaped surfaces 316 is axially symmetrical with the corresponding upper fan-shaped surface 315. Each of the lower fan-shaped surfaces 316 is connected to the spherical surfaces 313. Through the design of the lower fan-shaped surfaces 316, the lower sides of the second latching surfaces 314 are not connected. Therefore, when the angle cutting machine is used for cutting, the spherical shape of the bottom end of the rotating head 31 can be retained, so that the rotating head 31 can maintain the same contact area with the elastic member 4 (see Figure 10) when rotating, so the rotation will be smoother. This second embodiment can further shorten the processing time and reduce the manufacturing cost.

In summary, the pinless universal joint device of the present invention transmits torque by engaging the second latching surfaces 314 of the joint assembly 3 with the protrusions 211 of the cartridge seat 2. Therefore, there is no need to drill holes in the rotating head 31 or use additional latching pins, resulting in fewer components. Furthermore, the process of forming the two spherical surfaces 313 and the two second latching surfaces 314 on the rotating head 31 is relatively simple, thereby reducing manufacturing costs. Furthermore, the present invention increases the latching area between the rotating head 31 and the cartridge seat 2 by providing a large contact area between the second latching surfaces 314 and the protrusions 211, thereby enhancing durability and extending service life. Therefore, the present invention effectively achieves its objectives.

However, the above description is merely an example of the present invention and should not be used to limit the scope of the present invention. All simple equivalent changes and modifications made according to the scope of the patent application and the content of the patent specification of the present invention are still within the scope of the present patent.

2: Cartridge seat 201: Driven portion 202: Receiving groove 203: Step groove 204: Large aperture section 205: Small aperture section 21: Inner wall 210: Movable space 211: Protrusion 212: Curved portion 213: First latching surface 215: Annular groove 3: Connector assembly 31: Rotating head 311: Main body 312: Connecting section 313: Spherical portion 314: Second latching surface 315: Upper sector-shaped surface 316: Lower sector-shaped surface 32: Tool section 4: Elastic member 5: Positioning member Z: Height direction X: First direction L: Axis A1: Radius D1, D2, D3: Length r1: spherical radius r2: cylindrical radius D4: distance T1: tilt angle

Other features and functions of the present invention will be clearly presented in the embodiments with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional view illustrating a conventional universal joint; Figure 2 is a perspective view of an embodiment of a pinless universal joint device of the present invention; Figure 3 is a cross-sectional view taken along line III-III in Figure 2; Figure 4 is a perspective exploded view of the first embodiment; Figure 5 is a cross-sectional view taken along line V-V in Figure 3; Figure 6 is a side view of a joint assembly of the first embodiment; Figure 7 is a bottom view of the joint assembly; Figure 8 is a front view of the joint assembly; Figure 9 is a perspective cross-sectional view of the joint assembly; Figure 10 is a cross-sectional view similar to Figure 3 , illustrating the rotation of the connector assembly relative to a cartridge holder of the first embodiment to adjust the connection angle between the connector assembly and the cartridge holder; Figure 11 is a schematic cross-sectional view illustrating the engagement position of the connector assembly with the cartridge holder; Figure 12 is an exploded perspective view illustrating the connector assembly of a second embodiment of the pinless universal joint device of the present invention; Figure 13 is a side view of the connector assembly of the second embodiment; and Figure 14 is a bottom view of the connector assembly of the second embodiment.

2: Cartridge seat 202: Receiving groove 21: Inner wall 211: Protrusion 212: Curved portion 213: First latching surface 215: Annular groove 3: Connector assembly 31: Rotating head 311: Main body 312: Connecting section 313: Spherical surface 314: Second latching surface 315: Upper sector surface 32: Tool section 4: Elastic member 5: Positioning member Z: Height direction L: Axis

Claims (9)

A pinless universal joint device comprises: a cartridge seat including a driven portion and a receiving groove opposite to the driven portion in a height direction; the cartridge seat has an inner wall surface surrounding an axis parallel to the height direction and defining the receiving groove; the inner wall surface has two radially oppositely disposed protrusions and two radially oppositely disposed arc portions, and the two opposite sides of each protrusion are respectively connected to the arc portions. The two opposite sides of each arcuate portion are connected to the convex portions, each convex portion protrudes in the direction of the axis and has two oppositely inclined first latching surfaces, and the first latching surfaces of the convex portions and the arcuate portions jointly define two spaced movable spaces; a joint assembly rotatably connected to the cartridge seat, the joint assembly comprising: a rotating head rotatably disposed in the receiving groove of the cartridge seat The rotating head has two spherical portions respectively accommodated in the movable spaces, and two second latching portions connected to the spherical portions. The second latching portions are respectively configured to latch with the protrusions. Each of the spherical portions is connected to the second latching portions, and opposite sides of each of the second latching portions are respectively connected to the spherical portions. The arc of each of the spherical portions in a radial cross-section perpendicular to the axis is greater than 90 degrees and less than 140 degrees. The rotating head has a body and a connecting section connecting the body and the tool portion. The body forms the spherical portions and the second latching portions. The top edge of each spherical portion extends to the connecting section. The tool portion is connected to the rotating head and protrudes from the cartridge seat in the height direction. A positioning member is provided on the cartridge seat and configured to stop the rotating head so that the connector assembly is retained within the cartridge seat. The pinless universal joint device of claim 1, wherein the inclination angle of each first latch surface is between 3 degrees and 10 degrees. The pinless universal joint device of claim 2, wherein the rotating head further comprises two upper sector-shaped surface portions connected to the upper sides of the second latching surface portions, respectively, and the maximum length of each upper sector-shaped surface portion in a first direction perpendicular to the height direction is equal to the length of each second latching surface portion in the first direction. The pinless universal joint device of claim 3, wherein the maximum length of each upper sector-shaped surface portion in a direction perpendicular to the first direction is greater than or equal to the spherical radius of each spherical surface portion minus the cylindrical radius of each second latching surface portion. The pinless universal joint device as described in claim 3, wherein the upper sector-shaped surfaces are spaced apart in parallel. The pinless universal joint device of claim 2, wherein the spherical radius of each spherical portion is larger than the cylindrical radius of each second latching portion. The pinless universal joint device of claim 1 further comprises an elastic member installed in the cartridge and capable of being compressed to elastically press against the rotating head and the cartridge. The pinless universal joint device of claim 1, wherein the inner wall surface of the cylindrical seat further comprises an annular groove that fully encircles the axis and is higher than the protrusions and the arcuate portions, and the positioning member is a C-shaped buckle and is embedded in the annular groove. The pinless universal joint device of claim 1, wherein the rotating head further comprises two lower sector-shaped portions connected to the lower sides of the second latching portions, each of the lower sector-shaped portions being connected to the spherical portions.