Drive element for a hair cutting device with replaceable tip

Abstract

Hair cutting device (14) with an interchangeable tip (10, 78), a drive element (12, 84), a moving blade (26), and a cutting machine housing, wherein - the drive element (12, 84) is configured to drive the moving blade with a back-and-forth motion, and wherein - the tip further comprises an engagement section (66, 92) configured for engagement with the drive element (12, 84) of the hair cutting device (14), - the engagement section (66, 92) further comprises at least one tip support structure (74) configured to engage with at least one drive element support structure (72) arranged on the drive element (12, 84), characterized in that - the tip (10) is constructed and arranged in such a way that it can be replaced on the drive element (12, 84) without disassembling the cutting machine housing and can be released in a coaxial direction by a force relating to the longitudinal axis (b) of a neck (24) of the drive element (12, 84), - the tip support structure (74) is formed with at least one snap hole in the engagement section (66), and - the drive element mounting structure (72) is designed with at least one mounting pin corresponding to the snap hole on the neck (24) of the drive element (12, 84) so ​​that the snap hole and the mounting pin can form a snap connection.

Description

[0001] The present invention relates generally to hair cutting devices with a moving cutting blade and a drive system, and in particular to hair cutting machines with a blade set driven by rotary motor systems.

[0002] One type of hair clipper used for cutting hair employs an electric motor with an eccentric drive element attached to the armature rotor. A articulated gear converts the rotational motion into a linear, reciprocating blade motion.

[0003] Traditionally, a reciprocating or oscillating drive element is used to drive a moving cutting blade of a cutting blade set in a lateral, oscillating motion relative to a stationary cutting blade. The drive element has a contact section that engages with the moving blade to drive the blade via the oscillating motion. Significant wear occurs at a contact section of the drive element, leading to wear or failure of that contact section, while the rest of the drive element remains structurally relatively undamaged and intact.

[0004] Typically, once the contact section or tip wears out or fails, additional operating noise and / or a reduced stroke occur, resulting in an inadequate and / or inefficient cut. A user must then replace the entire drive unit, which requires some degree of disassembly of the drive system and usually the clipper housing to access and replace the drive unit. The replacement process can typically be time-consuming, involving disassembly and reassembly of the clipper. This process is not only time-consuming but also labor-intensive and requires some mechanical skill. Furthermore, the disassembly and reassembly can lead to further product failure if other clipper components are misaligned and / or damaged during the replacement process.

[0005] Therefore, there is a need for a drive element arrangement for a hair cutting device that addresses the disadvantages of the state of the art.

[0006] DE 3 224 223 A1 describes an electric shaver. The reciprocating electric shaver comprises a blade carrier block, which carries a plurality of inner cutting blades and is coupled to a first drive element that converts the rotary motion of a motor into a reciprocating motion, and an outer shearing blade, which is coupled to a second drive element that is moved reciprocally with a mechanical phase opposite to that of the first drive element. The cutting blades and the shearing blade are in sliding engagement with each other and move with opposite phases relative to each other. The relative torque of the shearing blade with respect to the cutting blades can be increased. Further generic hair-cutting devices are disclosed in US 2 294 713 A and US 3 570 122 A. SUMMARY OF THE INVENTION

[0007] The aforementioned requirements are met or exceeded by the present replaceable tip for use with a drive element of a hair clipper. The replaceable tip is configured to drive a moving blade and is designed and arranged so that it can be replaced on the drive element without disassembling the clipper housing.

[0008] An alternative interchangeable tip for a drive element of a hair clipper is also disclosed. The interchangeable tip is generally rectangular and is located at the end of the drive element. The interchangeable tip is configured to drive a moving blade.

[0009] A method for replacing a replaceable tip of a drive element without disassembling a cutting machine housing is also disclosed. The method comprises the steps of loosening and removing a blade assembly from the cutting machine housing. The replaceable tip is removed from the drive element, and a new replaceable tip is mounted on the drive element. Then the blade assembly is attached and secured to the cutting machine housing.

[0010] In another embodiment, a drive element with an interchangeable tip for a hair clipper is configured to drive a moving blade of the hair clipper. The interchangeable tip and the drive element are designed and arranged such that the interchangeable tip can be replaced on the drive element without disassembling the clipper housing. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a perspective view of a drive element mounted in a hair clipper drive system and an interchangeable tip with a set of blades arranged on the drive element in exploded view; Fig. 2 is a perspective exploded view of the drive system of Fig. 1, wherein the replaceable tip is removed from the drive element. Fig. Figure 3 is a perspective exploded view of a second embodiment, with the replaceable tip removed from the drive element. Fig. Figure 4 is an assembled perspective view of the interchangeable tip and drive element of Fig. 3; and Fig. Figure 5 is a sectional view of the replaceable tip and drive element along line 5-5 of Fig. 4. DETAILED DESCRIPTION OF THE EXECUTION FORMS

[0011] In Fig. 1 and Fig. 2 is an interchangeable tip for a powered hair clipper, collectively designated 10. Although the present device 10 is illustrated as an interchangeable tip on a drive element 12 for a hair clipper 14, which engages with a blade set 16, it is considered that the present operating principles can be implemented in any mechanical device in conjunction with the use of a drive system that contacts a moving or reciprocating element. In particular, the interchangeable tip 10 can be used in cutting machines, razors, trimmers, and the like.

[0012] The replaceable tip 10 is configured to be removable on a distal end 18 ( Fig. 2) of the drive element 12. It is considered that any configuration of a drive element 12 made of any material can be used. In the preferred embodiment, the drive element 12 is a rotary / linear mechanism with a body 20, a shoulder section 22, and a neck 24, which are formed in one piece from a material selected for durability, formability, and affordability. The drive element 12 is preferably moved in an actual linear manner with respect to the blade set, such that the drive element moves back and forth in a straight line along an axis “T” transverse to a longitudinal axis “a” of the cutting machine 14. The back-and-forth movement of the drive element 12 is parallel to the movement of a moving blade 26.

[0013] The drive element 12 operates as part of a drive system 28. The drive system 28 comprises a motor assembly 30 and a chassis with a base plate 32 having a pair of spaced-apart, generally parallel, perpendicularly projecting arms 34. Each of the arms 34 has a through-bore 36 dimensioned to receive a corresponding end of a linear drive shaft 38. The drive shaft 38 is oriented such that it lies parallel to the operating axis of the moving blades 26 and defines an operating path for the drive element 12. One end 40 of the drive shaft 38 is preferably toothed and is secured in a friction fit in the corresponding through-bore 36.

[0014] To enable the linear sliding of the drive element 12 on the drive shaft 38, the drive element includes a transverse through-bore 42. At least one and preferably two drive shaft bushings 44 are slidably located on the drive shaft 38 on an inner diameter and are slidably received in the through-bore 42 on an outer diameter.

[0015] In the drive element 12, the through-hole 42 is preferably located in the shoulder 22. The neck 24 projects from the shoulder 22, and at its end 18 it has the removable tip 10. The tip 10 is preferably configured for attachment to the moving blade 26 of the blade set 16. By fixing the relative deflection of the distal end 18 of the drive element 12 with the moving blade 26 ( Fig. 1) the moving blade moves laterally in relation to a stationary blade 48 and generally transversely to the longitudinal axis “a” of the cutting machine 14.

[0016] The body 20 defines a chamber 50 with an upper opening 52, which provides access to a sliding piece 54. The sliding piece 54 defines a lateral stroke of a bearing 56, which is rotatably engaged with a cam pin (58) of an eccentric cam 60. During operation, an armature rotor 62 rotates due to the force from the motor 30, the eccentric cam pin 58 follows an eccentric path defined by the sliding piece 54, and the drive element 12 is displaced laterally along the linear drive shaft 38. Thus, the rotational motion of the motor assembly 30 is converted into the linear motion of the moving blade 26. Although the present invention has been described with respect to a rotary / linear drive system 28, any device drive system powered by an electric motor that activates a moving or reciprocating element can be considered.

[0017] The replaceable tip 10, when arranged on the distal end 18 of the drive element 12, is the portion of the drive element that is in contact with the moving blade 26. Typically, the moving blade 26 has a receiving feature 64 (shown in dashed lines) configured to receive the replaceable tip 10. In the preferred embodiment, the receiving feature 64 is a notch or groove that receives the replaceable tip 10 or is adapted to transmit the transverse movement of the neck 24 to the moving blade 26. Preferably, the replaceable tip 10 engages tightly with the receiving feature 64, although it is taken into account that a slight displacement of the receiving feature relative to the replaceable tip may occur.

[0018] If the drive element 12 transmits a movement generally transverse to the longitudinal axis “a” of the cutting machine 24, the replaceable tip 10 is configured to remain enclosed within the receiving formation 64. Preferably, the replaceable tip does not move into or out of the receiving formation 64, or upwards or downwards, thereby reducing wear induced by shock loads and extending the service life of the replaceable tip 10.

[0019] However, through use, the replaceable tip experiences wear with respect to the receiving element 64. Such wear increases the amount of play of the tip 10 in the receiving element 64, which reduces the efficiency of the drive system 28, typically increases the operating noise of the cutting machine 14, and is generally undesirable. When the replaceable tip 10 wears out or otherwise fails, an advantage of the present replaceable tip is that it can be replaced without disassembling the drive system 28 to replace the entire drive element 12. Instead, only the blade assembly 16 needs to be removed from the cutting machine 14 to gain access to the replaceable tip 10.This is typically achieved by applying pressure to the side of the moving blade 26 of the blade assembly 16 to disengage the blade assembly from the cutting unit 14 by releasing a snap-fit. Alternatively, if fasteners are used to secure the blade assembly to the housing, the blade elements are released and the blade assembly is pulled off the cutting unit 14. In other units, a locking element must be released or moved to allow removal of the blade assembly. In such cases, the cutting unit body does not need to be disassembled. In some hair clippers 14, the blade assembly 16 is attached to the cutting unit only by a snap-fit. This allows the replaceable tip 10 to be pulled off the neck 24 of the drive element 12 using the user's fingers, pliers, or the like.When a new replaceable tip 10 is connected to the drive element 12, preferably by pressing it onto the neck 24, the blade set 16 can be reattached to the cutting machine.

[0020] According to Fig. 1 and Fig. Figure 2 is the first embodiment of the replaceable tip 10, generally rectangular, configured with an engagement section 66, preferably a countersunk bore, to receive the distal end 18 of the neck 24. An opening 68 (shown with dashed lines) towards the engagement section 66 is arranged on a proximal side 70 of the tip 10, and the neck 24 is inserted into the opening 68. The replaceable tip 10 is pressed onto the neck 24 and preferably secured in its position to encapsulate the distal end of the drive element 12.

[0021] At least one, but preferably several, retaining structures for the drive element 42, such as snap devices, pins, projections, or wedges, are arranged on the neck 24 for engagement with corresponding tip retaining structures 74, such as snap holes or recesses. It is also considered that other retaining structures 72, 74 can be used to hold the replaceable tip 10 on the distal end 18 of the drive element 12. When the retaining structures 72 of the drive element and the retaining structures 74 of the tip are engaged, the neck 24 extends within the replaceable tip 10 substantially along the longitudinal axis of the tip, but preferably the neck does not protrude through an opposite side 76 of the tip.In the preferred embodiment, the opposite side 76 is rounded in both the perpendicular and longitudinal directions with respect to the cutting machine 14. This configuration provides a localization function with the receiving formation 64 as well as a curved impact surface when the replaceable tip 10 is used for a curved movement (see ). Fig. 3 to 5).

[0022] In the Fig. Figures 3 to 5 represent an alternative embodiment of an interchangeable tip, collectively designated by 78. The interchangeable tip 78 generally has a wide end 80 and a beveled end 82 ( Fig. 5) rectangular. Similar to the first embodiment, the tip 78 has an engagement section 66. In the second embodiment, however, the engagement section 66 is preferably a through-bore extending from the chamfered end 82 through the entire tip 78 to the wide end 80.

[0023] In the corresponding drive element 84, an engagement element section 86 of a drive element, preferably a pin, is formed, preferably in one piece, such that it protrudes from the distal end 88 of a neck 90 for reception in an engagement section 92 of the replaceable tip 84. When the pin 86 is inserted into the chamfered end 82, the pin protrudes slightly from the wide end 80. Preferably, the pin 86 has a slight widening 94 ( Fig. 5) to maintain the relative position of the pin within the engagement section 92. Alternatively, the pin 86 may be flush with the wide end 80, or the pin may extend less than the full length of the replaceable tip 78. Other configurations are considered provided that the replaceable tip 78 is attached to the drive element 84.

[0024] The wide end of the replaceable tip 78 is received in the receiving formation 64 of the moving blade 26. The replaceable tip 78 has side ends 96 which are preferably slightly concave in the direction perpendicular to the engagement section 92, as shown in Fig. 3 is shown, or are configured in any other way to hold the tip within the receiving section 64. A contact of the moving blade 26 with the wide end 80 of the replaceable tip 78 and any additional contouring of the tip provides an additional engagement of the tip within the receiving formation 64.

[0025] The chamfered end 82 of the replaceable tip 78 and the drive element 84 preferably have a first and second locking configuration, such as an interlocking "V"-shaped geometry, to prevent rotation of the tip 78 relative to the drive element. Furthermore, the engagement section 92 and the pin 86, both preferably shaped to have a slight eccentricity about the longitudinal axis "b" of the replaceable tip, prevent rotation of the replaceable tip 78 relative to the drive element 84. In this embodiment of the tip 78, the axis "b" is inclined to the cutting machine axis "a", although other orientations are considered depending on the application. It is also considered that other shapes of the engagement sections 86 and 92 can be used, particularly if they are configured to interlock but not rotate relative to each other.Furthermore, a configuration with a round pin 86 and an engagement section 92 is considered, in which the additional inhibition of the eccentricity is not desired, provided that a relative movement of the tip to the drive element 84 is prevented.

[0026] The drive element 84, like the drive element 82, is a rotary / linear mechanism comprising a body 102, a shoulder section 104, and a neck 90, all formed in one piece from a material selected for durability, formability, and affordability. Preferably, the shoulder 104 is pivotably mounted on the cutting machine 14 via a pivot bore 108. Since the body 102 is driven by the motor assembly 30, the shoulder 104, like the neck 90, moves relative to the cutting machine 14, generally sliding transversely and in a curve about a longitudinal axis in "a" of the cutting machine around a rod 110. In this embodiment, a distal end 88 of the neck 90 moves along a slightly curved path.

[0027] The drive of the body 102 is preferably effected by coupling the drive element 84 with the motor arrangement 30 forming a drive system 112. In particular, the drive system 112 has an eccentric cam 114 that projects upward from the drive system into a cam receiving section 116 of the body 102. The cam receiving section 116 preferably includes an opening 118 in the body 102 configured to receive the cam 114 and, as a whole, circumscribes the cam 114. In a preferred embodiment, the cam 114 is preferably round, with a hollow center configured to be arranged eccentrically around a stationary shaft 120. When the motor 30 drives the drive element 84, a gear drive 122 rotates the cam 114 around the stationary shaft 120, and the eccentricity of the cam causes the body 102 to pivot about the pivot rod 110.

[0028] It is considered that further embodiments of drive elements may be used. In one considered embodiment of a (not shown) drive element, the drive element preferably has two legs that are fixedly attached to a cutting machine at a first end, and a bridging structure between the legs at a second end. Each leg is preferably resilient and configured to deform. Preferably, a cam or other mechanical element is coupled to the bridging structure to drive the drive element. When the cam forces a transverse movement on the bridging structure, the legs of the drive element deform, and the replaceable tip 10, 78, which is arranged on the bridging structure, moves back and forth.The replaceable tip 10, 78 has an engagement section configured to engage with the drive element at a distal end, preferably the bridging structure, for example by a snap-fit, sliding, fastening, or press fit, or any other method. Furthermore, it is considered that the replaceable tip 10, 78 can engage with both the drive element and the cam (or a similar mechanism) such that the cam directly transmits the force to the tip.

[0029] A detailed description of the preferred drive mechanism is disclosed in US patent application Ser. No. 10 / 929,531, entitled “Rotary Motor Clipper With Linear Drive System”, filed on August 30, 2004.

[0030] Although specific embodiments of the present replaceable tip and the method for replacing it have been presented and described, it should be understood by the person skilled in the art that changes and modifications to it can be carried out without deviating from the invention as described in the claims below.

Claims

[1] Hair cutting device (14) with an interchangeable tip (10, 78), a drive element (12, 84), a moving blade (26), and a cutting machine housing, wherein - the drive element (12, 84) is configured to drive the moving blade with a back-and-forth motion, and wherein - the tip further comprises an engagement section (66, 92) configured for engagement with the drive element (12, 84) of the hair cutting device (14), - the engagement section (66, 92) further comprises at least one tip support structure (74) configured to engage with at least one drive element support structure (72) arranged on the drive element (12, 84), characterized by , that - the tip (10) is constructed and arranged in such a way that it can be replaced on the drive element (12, 84) without disassembling the cutting machine housing and can be released in a coaxial direction by a force relating to the longitudinal axis (b) of a neck (24) of the drive element (12, 84), - the tip support structure (74) is formed with at least one snap hole in the engagement section (66), and - the drive element mounting structure (72) is designed with at least one mounting pin corresponding to the snap hole on the neck (24) of the drive element (12, 84) so ​​that the snap hole and the mounting pin can form a snap connection. [2] Hair cutting device (14) according to claim 1, wherein the engagement section (66, 92) is configured to receive a distal end (18, 86) of the drive element (12, 84). [3] Hair cutting device (14) according to one of the preceding claims, wherein the engagement section (66, 92) is configured to engage with a pin (86) that protrudes from the drive element (12, 84). [4] Hair cutting device (14) according to one of the preceding claims, wherein the tip (10, 78) transmits a curved movement to the moving blade (26) in relation to a stationary blade (48). [5] Hair cutting device (14) according to one of the preceding claims, wherein the tip (10, 78) transmits a curved movement of the moving blade (26) in relation to a stationary blade (48). [6] Hair cutting device (14) according to one of the preceding claims, wherein the tip (10, 78) engages with a receiving formation (64) of the moving blade (26). [7] Hair cutting device (14) according to one of the preceding claims, wherein the tip further comprises a locking formation (74, 100) on the tip (10, 78) configured to engage with a locking formation (72, 98) of the drive element (12, 84). [8] Hair cutting device (14) according to claim 7, wherein the tip locking formation (98) is beveled and arranged on one side of the tip (78), wherein the tip locking formation (98) and the locking formation (100) of the drive element (12, 84) are generally ‘V’-shaped.

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