Tool bit assembly and shaver

Abstract

The tool bit assembly comprises a static knife, a movable knife and a movable knife rest for bearing the movable knife, and a guide groove is formed in the movable knife rest and used for containing an eccentric shaft of a driving unit; the two opposite inner side walls of the guide groove are each provided with an independent rolling piece in a rotatable mode. When the eccentric shaft rotates, the circular motion of the eccentric shaft periodically acts on the two rolling pieces, so that the movable knife rest and the movable knife are driven to do transverse reciprocating motion relative to the static knife. The rolling piece can be a rolling shaft, a ball, a bearing or a cylindrical lining fixed by a pin shaft. Traditional sliding friction is converted into rolling friction, transmission noise is remarkably reduced, part abrasion is reduced, and the moving cutter operates more smoothly and efficiently.

Description

Technical Field

[0001] This invention relates to the field of personal care electrical appliances, and more particularly to a blade assembly and a shaver. Background Technology

[0002] In the design of existing electric shavers, there are usually two main parts: the body and the shaver head. The body houses the motor, and an eccentric shaft is mounted on the motor's rotating shaft. The shaver head mainly consists of a fixed blade and a moving blade. The moving blade is fixed by a moving blade holder, which has a guide groove. The eccentric shaft is embedded in the groove and, driven by the motor, moves the moving blade back and forth by stirring left and right.

[0003] However, this structure has obvious defects: when the eccentric shaft swings left and right in the guide groove, it generates a lot of friction with the groove wall, which not only causes significant operating noise, but also, since the moving blade holder is mostly made of plastic, long-term friction can easily cause serious wear, affecting service life and shaving efficiency.

[0004] To improve friction, some solutions attempt to install bearings on the eccentric shaft of the motor to enhance smoothness. However, this design still has shortcomings: if the bearing diameter is designed to be equal to the width of the guide groove, when the eccentric shaft rotates to the leftmost or rightmost end of its trajectory, the bearing will be simultaneously squeezed by the two side walls of the guide groove and unable to rotate, forced into a state of sliding friction. This results in two noticeable jerks per rotation, leading to uneven operation. If the width of the guide groove is increased to exceed the bearing diameter to maintain smoothness, the eccentric shaft will impact the groove wall when turning, increasing operating noise.

[0005] In summary, existing electric shavers still suffer from problems such as high friction loss, significant noise, and uneven operation in their moving blade transmission structure, which require further optimization and improvement. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a blade assembly and a shaver.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a cutter head assembly, comprising a stationary cutter, a moving cutter, and a moving cutter holder supporting the moving cutter. The moving cutter holder has a guide groove for accommodating an eccentric shaft of a drive unit. Two independent rolling elements are rotatably disposed on the two opposing inner sidewalls of the guide groove. When the eccentric shaft rotates, its circumferential motion periodically acts on the two rolling elements, driving the moving cutter holder and the moving cutter to reciprocate laterally relative to the stationary cutter.

[0008] By adopting the above technical solution, the sliding friction in traditional transmission is transformed into rolling friction, fundamentally solving the technical problems of high noise, easy wear, and jerky operation in electric shavers. This makes the moving blades run more smoothly and efficiently, and also extends the overall service life of the blade assembly.

[0009] As a preferred embodiment of the present invention, grooves are respectively provided on the two opposite inner sidewalls of the guide groove, and the rolling element is disposed in the corresponding groove; the rolling element is a roller, ball, or bearing.

[0010] By adopting the above technical solution, the rolling elements are specifically defined as standard or mature components such as rollers, balls, or bearings, making this solution easy to implement and promote. This helps ensure the stability of the transmission effect and the economic efficiency of the product.

[0011] As a preferred embodiment of the present invention, the rolling element is a cylindrical bushing, and the two opposite inner sidewalls of the guide groove are provided with grooves for accommodating the cylindrical bushing. The moving tool holder is provided with a pin that passes through the cylindrical bushing and positions it in the groove. The cylindrical bushing can rotate relative to the pin, and its outer cylindrical surface is at least partially exposed in the groove.

[0012] By adopting the above technical solution, the cylindrical bushing structure fixed by the pin is simple and reliable. Its outer cylindrical surface forms a line contact with the eccentric shaft, resulting in uniform force distribution and better wear resistance. The structure is also easy to process and assemble.

[0013] As a preferred embodiment of the present invention, the moving tool holder includes a mounting plate for mounting the moving tool and a boss extending from the mounting plate toward the side opposite to the stationary tool; the guide groove is formed on the boss; a through hole corresponding to the groove is formed on the boss, and the pin is inserted into the through hole.

[0014] By adopting the above technical solution, the mounting plate and the boss are integrally formed. This integrated structure enhances the overall rigidity, improves the stability of the transmission and the straightness of the moving blade movement, and helps to obtain a more reliable shaving effect.

[0015] As a preferred embodiment of the present invention, the boss includes two spaced-apart side plates and a baffle connecting the upper ends of the two side plates; the two side plates and the baffle together form the guide groove, one side of the guide groove being open; the groove extends through the side plates.

[0016] By adopting the above technical solution, the guide groove is defined as an open structure enclosed by two side plates and a baffle. This design not only facilitates the insertion and assembly of the eccentric shaft, but also makes the internal structure readily apparent, facilitating cleaning and maintenance during the production process. The through-groove design ensures smooth installation of the rolling components.

[0017] As a preferred embodiment of the present invention, the drive unit includes a drive motor and a rotating sleeve coaxially sleeved on the output shaft of the drive motor, and the eccentric shaft is eccentrically disposed at the end of the rotating sleeve.

[0018] By adopting the above technical solution, the split transmission structure combines a standard motor with a customized rotating sleeve, achieving standardization and cost reduction of core components. The rotating sleeve drives the output shaft and eccentric shaft of the motor, significantly improving the maintainability of the product and extending the motor life.

[0019] As a preferred technical solution of the present invention, a shaver includes the aforementioned blade assembly and a body, wherein the stationary blade is fixed to the body; a torsion spring is also provided inside the body, the main body of the torsion spring being housed in a mounting groove opened in the body, and its two elastic arms elastically abutting against the moving blade holder, forcing the moving blade to always press against the stationary blade.

[0020] By adopting the above technical solution, the shaving head assembly is combined with a body that has an automatic clamping function. The two elastic arms of the torsion spring continuously apply elastic force to the moving blade holder, ensuring that the moving blade is tightly fitted to the stationary blade in any working state, thereby achieving a stable and efficient shaving effect. This design also automatically compensates for blade wear, maintaining a good long-term user experience and improving safety during use. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the cutter head assembly of the present invention; Figure 3 This is a partial structural schematic diagram of the cutter head assembly of the present invention; Figure 4 This is a schematic diagram of the structure of the rolling element of the present invention configured as a cylindrical bushing.

[0022] Reference numerals: 1. Stationary blade; 2. Moving blade; 3. Moving blade holder; 4. Guide groove; 5. Eccentric shaft; 6. Rolling element; 7. Groove; 8. Cylindrical bushing; 9. Pin; 10. Mounting plate; 11. Boss; 12. Through hole; 13. Side plate; 14. Baffle; 15. Rotating sleeve; 16. Machine body; 17. Torsion spring; 18. Elastic arm; 19. Main body; 20. Drive motor. Detailed Implementation

[0023] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0024] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] like Figure 1-4 The cutter head assembly shown includes a stationary cutter 1, a moving cutter 2, and a moving cutter holder 3 that carries the moving cutter 2. The moving cutter holder 3 has a guide groove 4 for accommodating an eccentric shaft 5 of a drive unit. Two independent rolling elements 6 are rotatably arranged on the two opposite inner sidewalls of the guide groove 4. When the eccentric shaft 5 rotates, its circumferential motion periodically acts on the two rolling elements 6, driving the moving cutter holder 3 and the moving cutter 2 to reciprocate laterally relative to the stationary cutter 1.

[0026] By transforming the sliding friction in traditional transmission into rolling friction, the technical problems of high noise, easy wear, and jerky operation of the moving blade 2 in electric shavers are fundamentally solved. This makes the moving blade 2 run more smoothly and efficiently, and also extends the overall service life of the blade assembly.

[0027] In the core transmission structure of the cutter head assembly, the eccentric shaft 5 of the drive unit extends into the guide groove 4 of the moving tool holder 3 and interacts with two independent rolling elements 6 arranged on both sides of the guide groove 4. The low-friction, smooth transmission effect of this application can be achieved by adjusting the outer diameter of the eccentric shaft 5 and the net distance between the relative working surfaces of the two rolling elements 6. Specifically, there are several preferred dimensional fit relationships, all of which can achieve the purpose of this invention: In the first implementation, the diameter of the eccentric shaft 5 is smaller than the minimum clear distance between the opposing working surfaces of the two rolling elements 6. In this configuration, during rotation, the eccentric shaft 5's main working stroke involves alternately contacting and pushing one side of one of the rolling elements 6, thereby driving the moving tool holder 3 in reciprocating motion. At the moment of change in motion direction, the eccentric shaft 5 may briefly cease active contact with either rolling element 6, but due to the inertia of the moving tool 2 system or a small preload, the motion still transitions smoothly. The advantage of this method is that the eccentric shaft 5 and the rolling elements 6 always maintain a single, defined rolling contact point, completely eliminating sliding friction and achieving extremely low operating noise and minimal mechanical wear.

[0028] The second preferred embodiment: The diameter of the eccentric shaft 5 is equal to or very close to the net distance between the opposing working surfaces of the two rolling elements 6. In this configuration, when the eccentric shaft 5 rotates to near the midpoint of its trajectory, it may simultaneously maintain contact with or be in equilibrium with both rolling elements 6. Throughout the entire motion cycle, force transmission always occurs through the rolling elements 6. This method ensures a clearance-free fit between the eccentric shaft 5 and the rolling elements 6, resulting in direct and rapid motion transmission, avoiding the sliding friction and jerking sensation caused by the bearing being jammed by the groove wall in the prior art.

[0029] It should be noted that the changes in the various dimensional relationships mentioned above are all simple modifications based on the core concept of this application—namely, the installation of rotatable independent rolling elements 6 on the two opposing inner sidewalls of the guide groove 4 of the moving tool holder 3. As long as this core structure is adopted, regardless of whether the dimensional relationship between the eccentric shaft 5 and the rolling element 6 results in either "single-sided contact" or "double-sided contact" working states, the power transmission path has been fundamentally transformed from "sliding friction" in the prior art to "rolling friction," thereby jointly achieving the goals of reducing noise, reducing wear on the moving tool holder 3, and ensuring smooth operation.

[0030] The guide groove 4 has two opposite inner sidewalls with grooves 7, and the rolling element 6 is disposed in the corresponding groove 7; the rolling element 6 is a roller, ball, or bearing. Specifically limiting the rolling element 6 to standard parts or mature components such as rollers, balls, or bearings makes this solution easy to implement and promote. This helps ensure the stability of the transmission effect and the economy of the product.

[0031] The rolling element 6 is a cylindrical bushing 8 (preferably made of metal, such as copper). Grooves 7 for accommodating the cylindrical bushing 8 are formed on the two opposing inner walls of the guide groove 4. A pin 9 passes through the cylindrical bushing 8 and positions it within the groove 7. The cylindrical bushing 8 can rotate relative to the pin 9, and its outer cylindrical surface is at least partially exposed within the groove 7. The cylindrical bushing 8, fixed by the pin 9, has a simple and reliable structure. Its outer cylindrical surface forms line contact with the eccentric shaft 5, resulting in uniform force distribution and better wear resistance. This structure is also easy to process and assemble.

[0032] The moving blade holder 3 includes a mounting plate 10 for mounting the moving blade 2 and a boss 11 extending from the mounting plate 10 away from the stationary blade 1. A guide groove 4 is formed on the boss 11. A through hole 12 corresponding to the groove 7 is formed on the boss 11, and the pin 9 is inserted into the through hole 12. The mounting plate 10 and the boss 11 are integrally formed. This integrated structure enhances the overall rigidity, improves the stability of the transmission and the straightness of the moving blade 2's movement, and helps to obtain a more reliable shaving effect.

[0033] The boss 11 includes two spaced-apart side plates 13 and a baffle 14 connecting the upper ends of the two side plates 13; the two side plates 13 and the baffle 14 together enclose the guide groove 4, one side of which is open; the groove 7 penetrates through the side plates 13. This design defines the guide groove 4 as an open structure enclosed by the two side plates 13 and the baffle 14. This design not only facilitates the insertion and assembly of the eccentric shaft 5, but also makes the internal structure readily apparent, facilitating cleaning and maintenance during production. The through-groove groove 7 design ensures smooth installation of the rolling element 6.

[0034] The drive unit includes a drive motor 20 and a rotating sleeve 15 coaxially mounted on the output shaft of the drive motor 20. An eccentric shaft 5 is eccentrically positioned at the end of the rotating sleeve 15. This split-type transmission structure combines a standard motor with a customized rotating sleeve 15, achieving standardization and cost reduction of the core components. By linking the output shaft of the drive motor 20 and the eccentric shaft 5 through the rotating sleeve 15, the maintainability of the product is significantly improved, and the motor life is extended. Besides the indirect linkage between the eccentric shaft 5 and the drive motor 20, the output shaft of the drive motor 20 can also be directly eccentrically positioned.

[0035] A shaver includes the aforementioned blade assembly and a body 16, with a stationary blade 1 fixed to the body 16. A torsion spring 17 is also provided within the body 16, its main body housed within a mounting groove in the body 16. Its two elastic arms 18 elastically abut against the moving blade holder 3, forcing the moving blade 2 to always press against the stationary blade 1. The blade assembly is combined with a body 16 that has an automatic pressing function. By continuously applying elastic force to the moving blade holder 3 through the two elastic arms 18 of the torsion spring 17, it is ensured that the moving blade 2 is tightly fitted against the stationary blade 1 in any working state, thereby achieving a stable and efficient shaving effect. This design also automatically compensates for blade wear, maintaining a good long-term user experience and improving safety during use.

[0036] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as defined by the appended claims and their equivalents.

Claims

1. A tool head assembly, comprising a stationary tool (1), a moving tool (2), and a moving tool holder (3) supporting the moving tool (2), wherein the moving tool holder (3) has a guide groove (4) for accommodating an eccentric shaft (5) of a drive unit, characterized in that, On the two opposing inner walls of the guide groove (4), an independent rolling element (6) is rotatably provided; when the eccentric shaft (5) rotates, its circumferential motion periodically acts on the two rolling elements (6), driving the moving tool holder (3) and the moving tool (2) to reciprocate laterally relative to the stationary tool (1).

2. The cutter head assembly according to claim 1, characterized in that: The guide groove (4) has grooves (7) on its two opposite inner sidewalls, and the rolling element (6) is disposed in the corresponding groove (7); the rolling element (6) is a roller, ball or bearing.

3. The cutter head assembly according to claim 1, characterized in that: The rolling element (6) is a cylindrical bushing (8). The guide groove (4) has two opposite inner sidewalls with grooves (7) for accommodating the cylindrical bushing (8). The moving tool holder (3) has a pin (9) that passes through the cylindrical bushing (8) and positions it in the groove (7). The cylindrical bushing (8) can rotate relative to the pin (9), and its outer cylindrical surface is at least partially exposed in the groove (7).

4. The cutter head assembly according to claim 3, characterized in that: The moving tool holder (3) includes a mounting plate (10) for mounting the moving tool (2) and a boss (11) extending from the mounting plate (10) away from the stationary tool (1); the guide groove (4) is formed on the boss (11); the boss (11) is provided with a through hole (12) corresponding to the groove (7), and the pin (9) is inserted into the through hole (12).

5. The cutter head assembly according to claim 4, characterized in that: The boss (11) includes two spaced side plates (13) and a baffle (14) connecting the upper ends of the two side plates (13); the two side plates (13) and the baffle (14) together form the guide groove (4), one side of the guide groove (4) is open; the groove (7) is provided through the side plate (13).

6. The cutter head assembly according to claim 1, characterized in that: The drive unit includes a drive motor (20) and a rotating sleeve (15) coaxially sleeved on the output shaft of the drive motor (20), and the eccentric shaft (5) is eccentrically disposed at the end of the rotating sleeve (15).

7. A shaver comprising the blade assembly according to any one of claims 1-6, characterized in that: It also includes a body (16), the stationary blade (1) is fixed to the body (16); the body (16) is also provided with a torsion spring (17), the main body of the torsion spring (17) is housed in the mounting groove opened in the body (16), and its two elastic arms (18) elastically abut against the moving blade holder (3), forcing the moving blade (2) to always press against the stationary blade (1).

Images