Eccentric shaft with ball joint

Abstract

The utility model discloses an eccentric shaft with ball joint, it includes the shaft body and is located on the eccentric part of shaft body, eccentric part includes the cylinder that is connected on the upper end of shaft body and is located on the ball of cylinder upper end, is equipped with the inner recess groove of eccentric part side on the shaft body, and the inner recess groove one side contact cylinder surface wall. The ball is polished and polished and handles, when the motor drive shaft body rotates, the ball passes through the spatial curved surface movement track and converts the linear reciprocating motion of cutter head assembly to the rotary motion, and the ball will rub and generate heat with rotation, and then through the inner recess groove to the cylinder and the ball on it carries out the heat dissipation, to promote the service life of this eccentric shaft and reduce the wear and tear degree of ball operation.

Description

Technical Field

[0001] This utility model relates to the field of eccentric shafts, and in particular to an eccentric shaft with a ball joint. Background Technology

[0002] In reciprocating electric shavers, the eccentric shaft (or crankshaft) is the core transmission component that drives the shaver head assembly to perform high-speed reciprocating motion. Its mechanical performance and service life directly affect the shaving efficiency and user experience of the entire machine.

[0003] Eccentric shafts achieve beard shearing by converting the rotational motion of a motor into the linear reciprocating motion of a blade. However, this dynamic conversion process presents significant tribological challenges: under high-frequency operating conditions (typically 8,000-15,000 times / minute), the contact interface between the eccentric shaft and the matching bearing / sleeve is continuously subjected to alternating loads. If there is a lack of effective lubrication during long-term operation, the metal / plastic friction pair will gradually generate wear particles, resulting in a gradual increase in the mating clearance.

[0004] Mechanical wear can trigger a series of chain reactions. Initially, it manifests as slight vibrations and howling noise caused by increased axial movement (sound pressure level can rise by 15-20dB). In the middle stage, it causes a decrease in shaving efficiency due to the deviation of the blade travel trajectory. In the end, it may develop into motion jamming or even complete lock-up due to wear failure, causing the drive system to fail. Utility Model Content

[0005] In view of this, the present invention addresses the deficiencies of the existing technology, and its main purpose is to provide an eccentric shaft with a ball joint. This solves the problem that the contact interface between the eccentric shaft and the matching bearing / sleeve is continuously subjected to alternating loads, and if there is a lack of effective lubrication during long-term operation, the metal / plastic friction pair will gradually generate wear particles, resulting in a gradual increase in the mating clearance.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: an eccentric shaft with a ball joint, comprising a shaft body and an eccentric portion disposed on the shaft body, the eccentric portion comprising a column connected to the upper end of the shaft body and a ball disposed on the upper end of the column body, the shaft body being provided with an inner groove located next to the eccentric portion, and one side of the inner groove contacting the surface wall of the column body.

[0007] Furthermore, the column is conical with a narrow end and a wide end, and the sphere is located on the narrow end of the column.

[0008] Furthermore, the axis is hexagonal, and the prism is located between any two sides.

[0009] Furthermore, the two sides of the shaft adjacent to the column are divided into a first side and a second side. The distance between the edge of the first side and the column is the first spacing, and the distance between the edge of the second side and the column is the second spacing. The second spacing is greater than the first spacing.

[0010] Furthermore, the top of the sphere is provided with a cavity, the inner cavity of which is provided with multiple through holes extending out of the outer side of the sphere, and the cavity is filled with solid grease.

[0011] Furthermore, the through hole is tapered, with the diameter of the end of the through hole closer to the cavity being smaller, and the diameter of the end of the through hole farther from the cavity being larger.

[0012] Furthermore, the end with the larger diameter of the through hole is provided with oil-absorbing cotton, and one side of the oil-absorbing cotton is adapted to the surface of the sphere.

[0013] Furthermore, the insertion end of the cavity is threaded with a sealing element.

[0014] Compared with the prior art, this utility model has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solution, after the ball is polished and ground, when it rotates with the motor-driven shaft, the ball converts the rotational motion into the linear reciprocating motion of the cutter head assembly through the spatial curved surface motion trajectory. The ball will generate heat through friction as it rotates, and then the internal groove will dissipate heat from the column and the ball on it, so as to improve the service life of the eccentric shaft and reduce the wear of the ball during operation.

[0015] To more clearly illustrate the structural features and effects of this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0016] Figure 1 This is a perspective view of Embodiment 1 of this utility model.

[0017] Explanation of reference numerals in the attached diagram: Shaft 10, inner groove 11, first side 12, first spacing 121, second side 13, second spacing 131; Eccentric part 20, column 21, sphere 22, cavity 221, through hole 222, oil-absorbing cotton 223, sealing part 224. Detailed Implementation

[0018] Please refer to Figure 1As shown, this illustrates the specific structure of a preferred first embodiment of the present invention, which is an eccentric shaft with a ball joint. It includes a shaft body 10 and an eccentric portion 20 disposed on the shaft body 10. The eccentric portion 20 includes a column 21 connected to the upper end of the shaft body 10 and a ball 22 disposed on the upper end of the column 21. The shaft body 10 has an inner groove 11 located beside the eccentric portion 20, and one side of the inner groove 11 contacts the surface wall of the column 21. The ball 22 is polished and, when the shaft body 10 is driven to rotate by a motor, the ball 22 converts the rotational motion into the linear reciprocating motion of the cutter head assembly through a spatial curved surface motion trajectory. The ball 22 generates heat through friction during rotation, and the inner groove 11 dissipates heat from the column 21 and the ball 22 thereon, thereby improving the service life of the eccentric shaft and reducing the wear of the ball 22 during operation.

[0019] For example, the column 21 is conical with a narrow end and a wide end, and the sphere 22 is disposed on the narrow end of the column 21. The column 21 adopts a conical geometry design, and its axial cross section is tapered, transitioning from the wide end (base end) to the narrow end (free end). This conical structure effectively disperses axial and radial loads through smooth cross-sectional changes, significantly reducing the stress concentration factor, especially in the connection area between the narrow end and the sphere 22. In addition, the sphere 22 is fixed to the narrow end of the column 21 by interference fit or welding process, forming an eccentric mass block, whose center of mass is offset from the rotation axis, thereby converting the rotational motion of the motor into the high-frequency reciprocating motion of the cutter head.

[0020] For example, the shaft 10 is hexagonal, and the column 21 is located between any two sides. The six equal-length sides form a 120° angle, which enhances the torsional stiffness of the shaft 10, prevents slippage under high torque loads, and facilitates precise alignment with the motor drive slot or coupling during assembly. The column 21 is located between any two adjacent sides of the shaft 10, and its axis is eccentrically arranged with respect to the rotation center of the shaft 10, forming an asymmetrical mass distribution, which can adjust the stroke and frequency of the cutting head.

[0021] The two sides of the shaft 10 adjacent to the column 21 are divided into a first side 12 and a second side 13. The distance between the side edge of the first side 12 and the column 21 is the first spacing 121, and the distance between the side edge of the second side 13 and the column 21 is the second spacing 131. The second spacing 131 is greater than the first spacing 121.

[0022] For example, the top of the sphere 22 is provided with a cavity 221, and the inner cavity of the cavity 221 is provided with a plurality of through holes 222 extending outward from the outer side of the sphere 22, and the cavity 221 is filled with solid grease. The opening of the through holes 222 provides an outlet for the solid grease in the cavity 221, so that when the sphere 22 rotates, the lubricating oil can be coated on the cutting head assembly through friction, thereby reducing the degree of wear when the sphere 22 rotates.

[0023] For example, the through hole 222 is tapered, and the diameter of the end of the through hole 222 near the cavity 221 is smaller, while the diameter of the end of the through hole 222 away from the cavity 221 is larger. Because the diameter of the end of the through hole 222 connected to the cavity 221 is smaller, the outflow rate of solid grease in the cavity 221 can be effectively reduced, thereby improving the service life of the eccentric shaft in this application.

[0024] For example, the end of the through hole 222 with a larger diameter is provided with an oil-absorbing cotton 223, and one side of the oil-absorbing cotton 223 is adapted to the surface of the sphere 22. The oil-absorbing cotton 223 can collect solid grease and increase the service life of solid grease.

[0025] For example, the insertion end of the cavity 221 is threadedly connected to a closure 224. The closure 224 is installed inside the cavity 221 to prevent solid grease from falling out of the cavity 221.

[0026] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the technical scope of the present utility model. Therefore, any minor modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. An eccentric shaft with a ball joint, comprising a shaft body (10) and an eccentric portion (20) disposed on the shaft body (10), characterized in that: The eccentric portion (20) includes a column (21) connected to the upper end of the shaft (10) and a sphere (22) located at the upper end of the column (21). The shaft (10) has an inner groove (11) located next to the eccentric portion (20), and one side of the inner groove (11) contacts the surface wall of the column (21).

2. An eccentric shaft with a ball joint according to claim 1, characterized in that: The column (21) is conical and has a narrow end and a wide end, and the sphere (22) is located on the narrow end of the column (21).

3. An eccentric shaft with a ball joint according to claim 1, characterized in that: The shaft (10) is hexagonal, and the prism (21) is located between any two sides.

4. An eccentric shaft with a ball joint according to claim 3, characterized in that: The two sides of the shaft (10) adjacent to the column (21) are divided into a first side (12) and a second side (13). The distance between the side edge of the first side (12) and the column (21) is the first spacing (121), and the distance between the side edge of the second side (13) and the column (21) is the second spacing (131). The second spacing (131) is greater than the first spacing (121).

5. An eccentric shaft with a ball joint according to claim 1, characterized in that: The top of the sphere (22) is provided with a cavity (221), the inner cavity of the cavity (221) is provided with a plurality of through holes (222) extending out of the outer side of the sphere (22), and the cavity (221) is filled with solid grease.

6. An eccentric shaft with a ball joint according to claim 5, characterized in that: The through hole (222) is tapered, and the diameter of the through hole (222) closer to the cavity (221) is smaller, while the diameter of the through hole (222) further away from the cavity (221) is larger.

7. An eccentric shaft with a ball joint according to claim 6, characterized in that: The larger end of the through hole (222) is provided with oil-absorbing cotton (223), and one side of the oil-absorbing cotton (223) is adapted to the surface of the sphere (22).

8. An eccentric shaft with a ball joint according to claim 6, characterized in that: The cavity (221) is threadedly connected to a closure (224) at the insertion end.

Images