This application is based on related Israeli Application No. 160955, filed Mar. 18, 2004, in the Israeli Intellectual Property Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to hair clippers generally, and, more particularly, to a hair cutting apparatus, including an extendable hair engagement comb.
2. Description of the Related Art
Conventional hair clippers with varying cut length capability have been well known for some time. Generally, these included devices in which a movable blade is moved relative to a stationary blade for varying a cut length of hairs by moving an adjuster handle mounted on a housing of the hair clipper in a direction along the longitudinal axis of the housing. The movable blade is interlocked with the adjuster handle through a linkage member in such a manner that the movable blade is moved in a rearward direction along the longitudinal axis to reduce the cut length when the adjuster handle is moved in a forward direction along the longitudinal axis.
However, since the movable blade in conventional devices is urged against the stationary blade by a torsion spring to provide a suitable spring bias to cause a hair shearing reciprocating motion of the movable blade on the stationary blade, a relatively large manipulation force is required to slide the adjuster handle and therefore the movable blade against a friction between the blades when adjusting the cut length of the hairs.
In addition, the adjuster handle of the conventional devices includes a latch means capable of stably holding a shearing position of the movable blade relative to the stationary blade during the shearing operation. The latch means includes a release knob projecting on a portion of the adjuster handle to be accessible by a finger of an operator manipulating the handle. The release knob is provided to unlatch the adjustor handle upon being pressed to thereby permit a sliding movement of the handle for varying the cut length. Eventually, the operator is required to press the release knob for sliding the adjuster handle besides the above described manipulation force. This is inconvenient and is therefore a cause of accumulating fatigue of a wrist or fingers of the operator when shearing the hairs while varying the cut length continuously and manually. Additionally, it may be expected that such linkage member and latch means create difficulties because of necessary complex structures.
These problems have been addressed in hair clippers that have a cutter head on the front end of a housing which includes a toothed stationary blade and a toothed movable blade reciprocating on the stationary blade in a hair shearing engagement between individual toothed edges thereof. The movable blade is slidable relative to the stationary blade in an edgewise direction perpendicular to the reciprocating motion of the movable blade for varying a cut length of hairs. An adjuster handle is slidably fitted on an outer round surface of the housing and linked to the movable blade through a linkage member such that the movable blade is shifted in the edgewise direction to increase and reduce the cut length by rotating the adjuster handle about a longitudinal axis of the housing.
However, since the cutting blade is moved relative to the stationary blade, the ability to cut hair at any particular length is limited to the distance between the stationary blade from the housing, which is predetermined at the time of manufacture and which is necessarily relatively short relative to desired hair lengths for many people.
Further, since the hair-cutting blade is moved relative to the body of the device, the blade may be damaged during the course of the lifetime of the blade, resulting in lowered reliability and cutting efficiency.
An aspect of the present invention provides a hair cutting apparatus, comprising a chassis to support a motor to drive a cutting blade, a rotary ring, including an inner circumferential surface, rotatably mounted on said chassis,a threaded screw having a head including an outer circumferential surface to engage with the inner circumferential surface of the rotary ring, and a shaft including threads, the threaded screw rotating in response to the rotation of the rotary ring, a longitudinal positioner having threads to engage with said threads of the threaded screw, to move in a longitudinal direction relative to the chassis in accordance with the rotation of the threaded screw and a hair engagement comb coupled with said longitudinal positioner to position hair to be cut by the cutting blade.
Another aspect of the invention provides a hair cutting apparatus, including a chassis to support a motor to drive a cutting blade, the apparatus comprising a rotary ring, including an inner circumferential surface, rotatably mounted on said chassis, a threaded screw, constrained within said chassis against non-rotational movement, having a head including an outer circumferential surface to engage with the inner circumferential surface of the rotary ring and a shaft including threads, the threaded screw rotating in response to the rotation of the rotary ring, a longitudinal positioner, having a socket including threads to engage with said threads of the threaded screw, to move in a longitudinal direction relative to the chassis in accordance with the rotation of the threaded screw, and a hair engagement comb coupled with said longitudinal positioner to position hair to be cut by the cutting blade.
Another aspect of the invention provides a hair cutting apparatus, including a chassis to support a motor to drive a cutting blade, the apparatus comprising a rotary ring, including an inner circumferential surface, rotatably mounted on said chassis, a threaded screw, constrained within said chassis against non-rotational movement, having a head including an outer circumferential surface to engage with the inner circumferential surface of the rotary ring and a shaft including threads, the threaded screw rotating in response to the rotation of the rotary ring, and a longitudinal positioner, having a socket including threads to engage with said threads of the threaded screw, to position a hair engagement comb at a desired distance from the cutting blade in accordance with the rotation of the threaded screw.
Another aspect of the invention provides a hand held hair cutting apparatus, including a cutting assembly, comprising a first member, disposed on a surface of the apparatus, to be selectively moved by a user in forward and reverse directions, a second member, disposed within the apparatus, to transform the movement of the first member into linear movement relative to the cutting assembly, and a third member, extending from the second member to an exterior of the apparatus, to position a hair engagement device a distance from the cutting assembly in accordance with the selection of the user.
Still yet another aspect of the invention provides a method of operating a hand held hair cutting apparatus, including a cutting assembly, comprising selectively moving a first member, disposed on a surface of the apparatus, in forward and reverse directions, transforming the movement of the first member into linear movement based on an amount of the selective movement of the first member relative to the cutting assembly, and positioning a hair engagement device a distance from the cutting assembly in accordance with the linear movement.
Additional and/or other aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.
Reference is now made to
As seen in
A rotatable hair length control ring 114 is rotatably mounted onto a forward edge 113 of rear housing portion 100. The rotatable hair length control ring 114 selectively positions a hair engagement comb 116 along an axis 102 in variable positions along a longitudinal direction. A rotatable motion of hair length control ring 114 about the axis 102 is converted to longitudinal motion of the hair engagement comb 116 about the axis 102 by a comb driving assembly 120, which is located within a forward housing portion 122.
A cutting blade assembly 110 is located at a forward end of forward housing portion 122 and the hair engagement comb 116 is located forwardly of the cutting blade assembly 110 along the longitudinal axis 102 by a selectable distance related to an amount of the rotation of the hair length control ring 114, as seen in
With reference to
The threaded screw 130 engages a slidable longitudinal positioner 134 including a support portion 136 and an elongated portion 138 which is formed with a threaded socket 140. A threading pattern of the threaded socket 140 generally corresponds with that of the threaded screw. A forward end of elongated portion 138 may engage with an extension portion 142 of the hair engagement comb 116 in a snap fit engagement.
Thus, a manual rotation of the hair length control ring 114 produces a corresponding rotation of the threaded screw 130. This, in turn, produces a longitudinal displacement of the longitudinal positioner 134 along the axis 102.
It is understood that the tooth-to-tooth engagement between the threaded screw 130 and the array 150 of teeth 152 of the hair length control ring 114 is only one embodiment of the invention. An alternate embodiment, in which the outer surface of the threaded screw 130 and the inner surface of the hair length control ring 114 comprise frictional surfaces that contact with each other, is possible. According to this embodiment, a rotation of the hair length control ring 114 causes a corresponding rotation of the threaded screw 130 due to the frictional contact between the outer and inner surfaces of the hair length control ring 114 and the threaded screw 130. Of course, yet additional embodiments, which provide for similar effects, are also possible.
Reference is now made to
An outer surface 158 of the hair length control ring 114 may be formed with dimples 160 to enhance a frictional engagement therewith by the fingers of the user. A forward facing flange 162 may be provided for rotational sliding engagement between the hair length control ring 114 and a corresponding rearward facing edge of the forward housing 122.
Reference is now made to
Reference is now made to
Reference is now made to
Reference is now made to
Various mechanisms in addition to the row of protrusions 155 to hold the hair engagement comb 116 in place relative to the forward housing 122 will now be described with reference to methods of operation of the hair clipping device of the present invention. First, once a user has positioned the hair engagement comb 116 in a desired position and thereafter begins cutting a hair cutting operation, it is understood that a compressing force applied to the hair engagement comb 116 to tend to cause the hair engagement comb 116 to move toward the forward housing 122 will be applied by the surface of a body undergoing the hair cutting operation. According to an embodiment of the invention, however, an angle and friction generated between the corresponding threads of the threaded screw 130 and the threaded socket 140 as well as the friction generated between the teeth 152 of the array 150 and the teeth 133 of the screw head 132 combine to prevent a compression of the hair engagement comb 116 toward the forward housing 122 under a compressing force applied by the body.
According to other embodiments of the invention, a compression of the hair engagement comb 116 toward the forward housing 122 may be prevented by a latch system and/or a locking system which selectively disengages the threaded screw 130 from either the threaded socket 140 or the array 150 of teeth 152 and/or prevents a rotation of either the threaded screw 130 and the array 150 of teeth 152 or a longitudinal movement of the threaded socket 140.
It is understood that such a latch system and/or a locking system may provide either predetermined cutting positions at which the hair clipping device may be set, or may allow a user to set a hair cutting length at any length given the length of the extension portion 142 of the hair engagement comb 116.
With respect to
With respect to
Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.
Number | Date | Country | Kind |
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160955 | Mar 2004 | IL | national |