Patent Description:
Electric hair shavers, clippers or trimmers may incorporate a clipper blade assembly having a stationary blade and a reciprocating blade. The stationary blade and the reciprocating blade each have a plurality of teeth along leading edges of the blades. The reciprocating blade oscillates with respect to the stationary blade to trim hair disposed between the teeth. Examples of hair clippers are disclosed in commonly assigned <CIT>, <CIT>, and <CIT>. Prior art document <CIT> discloses the preamble of claim <NUM>.

Several deficiencies are inherent in conventional clipper designs. For example, adjusting the length of cut between the cutting blades, sometimes referred to as "gap" in the barber industry, often requires removal of the blade assembly from the handle, and securing the relative positions of the blades followed by reattachment of the blades to the handle. This operation is difficult in and of itself. Compounding the issue is that the adjustment of the blades often results in angulation of one blade relative to another. This is undesirable in that the resulting cut with the angulated blades is inconsistent, thereby resulting in additional operator difficulties.

Accordingly, the present disclosure is directed to further improvements in hair clippers, shavers, trimmers, etc. For example, illustrative embodiments of the present disclosure permit adjustment of the blade cut while the blades are mounted to the handle. In exemplary embodiments, the present invention further ensures direct relative linear movement of the cutting blades such that the cutting blades are "aligned" with respect to each other. In certain embodiments, the cutting edges of the cutting blades are in parallel relation to each other when in the aligned position. These features amongst other features provides a clean, consistent and easily controllable cut.

In accordance with claim <NUM>, a hair cutting system includes a handle defining a longitudinal axis, a strut mounted to the handle and a hair cutting blade assembly coupled to the strut. The cutting blade assembly includes a stationary blade defining cutting teeth having blade edges and a movable blade defining cutting teeth having blade edges and capable of reciprocal movement relative to the stationary blade in a horizontal direction. The movable blade and the stationary blade are movable relative to each other in a longitudinal direction to adjust a longitudinal position of the movable blade relative to the stationary blade to selectively vary a distance between the blade edges of the stationary blade and the blade edges of the movable blade. A releasable lock is configured to selectively lock and release the stationary blade and the movable blade with respect to each other in the longitudinal direction.

The hair cutting system according to claim <NUM> further includes an adjustment tool mounted relative to the cutting blade assembly and operatively engageable with the movable blade. The adjustment tool and the strut are correspondingly configured such that longitudinal movement of the adjustment tool imparts corresponding longitudinal movement of the movable blade to facilitate adjustment of the longitudinal position of the movable blade relative to the stationary blade. Optional features are mentioned hereafter. The adjustment tool may include inner walls defining an internal recess for at least partially receiving the strut wherein the inner walls cooperating with the strut during longitudinal movement of the movable blade to facilitate linear movement of the movable blade relative to the stationary blade.

The releasable lock includes at least one alignment fastener coupled to the movable blade, and configured to releasably secure the movable blade at a plurality of select longitudinal positions. The alignment fastener may include an alignment screw.

A slider may be mounted within a recess of the stationary blade. The slider includes a threaded anchor for at least partial threaded reception of the alignment screw. The slider is configured to reciprocate within the recess of the stationary blade during reciprocal movement of the movable blade.

The adjustment tool includes a driver releasably mounted thereto, which is manipulatable to control movement of the alignment screw. One or more alignment screws may be provided. The one or more alignment screws are accessible to the driver with the cutting assembly mounted to the strut.

A bracket may be disposed between the movable blade and the strut. The bracket includes at least one elongated opening to receive the screw. The screw traverses the elongated opening during longitudinal movement of the movable blade.

Other features of the present disclosure will be appreciated from the following description of same.

Various embodiments of the present disclosure are described hereinbelow with references to the drawings, wherein:.

Referring now to the drawing figures wherein like reference numerals identify similar or like components throughout the several views, <FIG> illustrate the hair cutting system in accordance with the principles of the present disclosure. The hair cutting system <NUM> includes a hair cutter <NUM> and an adjustment tool <NUM> which is releasably mountable to the hair cutter <NUM>. The hair cutter <NUM> may be a hair clipper, a shaver, a hair trimmer or any other personal grooming device capable of cutting, trimming, shaving etc., hair from any part of the human body. For simplicity, the device will be referred to hereinafter as a "hair cutter". The hair cutter <NUM> includes a handle <NUM> defining a longitudinal axis "k" and a cutting blade assembly <NUM> mounted adjacent the remote end of the handle <NUM>. The handle <NUM> includes a drive mechanism, schematically illustrated in <FIG>, as reference numeral <NUM>. The drive mechanism <NUM> may be powered by an external electrical power source connected by an electrical cord (not shown) or it may include a battery-operated motor and one or more drive shafts <NUM> for imparting movement, including but not limited to oscillating, reciprocating or any other type of motion to the cutting blade assembly <NUM>. When adjustment of the blade gap is desired, the adjustment tool <NUM> is utilized to be operated as described in greater detail hereinbelow. In general, the adjustment tool <NUM> is used to facilitate positioning and proper alignment of the cutting blades of the cutting blade assembly <NUM> while adjusting the gap in order to vary the length of cut of the cutting blade assembly <NUM> for cutting beards, hair, body hair etc..

Referring now to <FIG>, the adjustment tool <NUM> will be discussed. The adjustment tool <NUM> has a pair of spaced walls <NUM>, e.g., proximal wall 24a and distal wall 24b, arranged in the general shape of a "U" which are connected by a base <NUM>. The spaced walls 24a, 24b define a spacing <NUM> therebetween which at least partially receives the cutting blade assembly <NUM> to mount the adjustment tool <NUM> to the cutting blade assembly <NUM>. A rear wall <NUM> extends upwardly from the distal wall 24b and engages the rear of the cutting blade assembly <NUM> as shown in <FIG>. In one exemplary embodiment, the spacing <NUM> between the spaced walls <NUM> is dimensioned such that the spaced walls <NUM> and the rear wall <NUM> engage the front and rear of the cutting blade assembly <NUM> in friction relation therewith. It is also envisioned that the spacing <NUM> defines a dimension which is less than the width of the cutting blade assembly <NUM> whereby the spaced walls <NUM> and/or the rear wall <NUM> flex slightly outward to further facilitate securement of the adjustment tool <NUM> to the cutting blade assembly <NUM>. Other mechanisms are also envisioned. The adjustment tool <NUM> further includes a driver receptacle <NUM> and opposed detents <NUM> within the driver receptacle <NUM>. A pair of lock ledges <NUM> are mounted adjacent the rear wall <NUM> and depend inwardly into the spacing <NUM>.

The proximal wall 24a of the adjustment tool <NUM> defines an internal recess <NUM> which defines a dimension "d1" the significance of which will be described hereinbelow. The proximal wall 24a further defines upper surfaces <NUM> which assist in adjusting the blades of the cutting blade assembly <NUM>. Moreover, the internal recess <NUM> and the upper surfaces <NUM> of the proximal wall 24a cooperate to ensure direct linear adjustment of the cutting blade assembly <NUM> without any rotation, angulation etc. of the blades of the cutting blade assembly <NUM> relative to each other.

With reference to <FIG> and <FIG>, the adjustment tool <NUM> includes a driver <NUM> having a drive handle <NUM> and a drive member <NUM> extending from the drive handle <NUM>. The drive handle <NUM> includes a peripheral recess <NUM> which cooperates with the opposed detents <NUM> within the driver receptacle <NUM> of the adjustment tool <NUM> to secure the drive handle <NUM> to the adjustment tool <NUM>. The drive member <NUM> may have a hexagonal head or other shaped head, e.g., a Phillips head, a straight head as well as any other polygon configuration. The driver <NUM> is utilized to loosen and tighten fastener elements, e.g., screws of the cutting blade assembly <NUM> to permit selective adjustment of the cutting blades to vary a length of cut as will be discussed hereinbelow. The drive member <NUM> may further be secured within the spacing <NUM> of the adjustment tool <NUM> by the lock ledges <NUM>. The lock ledges <NUM> may bias outwardly upon insertion of the drive member <NUM> and then return to their normal positions securing the drive member <NUM>, for example, engaging the outer periphery of the drive member <NUM>.

Referring now to <FIG>, further details of the hair cutter <NUM> and the cutting blade assembly <NUM> will be discussed. <FIG> illustrates the cutting blade assembly <NUM> prior to being assembled to the handle <NUM>. With reference to <FIG> and the exploded view of <FIG>, the hair cutter <NUM> includes a strut <NUM> which is directly mounted to the handle <NUM> and to the cutting blade assembly <NUM>. The strut <NUM> is dimensioned to displace the cutting blade assembly <NUM> away from the handle <NUM> to permit access to various features of the cutting blade assembly <NUM> without having to remove the cutting blade assembly <NUM> from the handle <NUM>. The strut <NUM> defines a central opening <NUM> for receiving a screw <NUM> and two side openings <NUM> extending completely through the strut <NUM>. As best depicted in <FIG>, the strut <NUM> defines an outer dimension "w1" which generally approximates the internal dimension "d1" of the proximal wall 24a of the adjustment tool <NUM>.

The cutting blade assembly <NUM> includes, from proximal to distal, an oscillation spring <NUM>, a bracket <NUM>, a movable blade <NUM>, a slider <NUM> and a stationary blade <NUM>. The oscillation spring <NUM> at least partially resides in a pair of distal recesses <NUM> in the strut <NUM> and engages the bracket <NUM>, e.g., spring holders <NUM> of the bracket <NUM> (<FIG>). The oscillation spring <NUM> normally biases the bracket <NUM> and thus the movable blade <NUM> to a central-most position in general alignment with the longitudinal axis "k. " The bracket <NUM> includes a central segment <NUM> (<FIG>) having two opposed vertical walls <NUM> which receive the eccentric rotating shaft (not shown in <FIG>) extending from the handle <NUM>. Rotation of the eccentric shaft causes the bracket <NUM> and the movable blade <NUM> secured to the bracket <NUM> to correspondingly oscillate in a known manner.

As best depicted in <FIG> and <FIG>, the movable blade <NUM> incudes cutting teeth <NUM> defining an outer cutting edge. The movable blade <NUM> further includes a proximal ledge <NUM> upon which the bracket <NUM> may reside and two elongated outer rectangular-shaped openings <NUM> (see also <FIG>). The rectangular-shaped openings <NUM> receive alignment screws <NUM> which extend through the elongated openings <NUM> of the bracket <NUM>. The rectangular-shaped openings <NUM> and the elongated openings <NUM> are generally elongated in the vertical direction.

As best illustrated in <FIG> and <FIG>, the slider <NUM> is generally rectangular in shape and has two rectangular openings <NUM> in alignment with the rectangular-shaped openings <NUM> of the movable blade <NUM>. Secured within the openings <NUM> of the slider <NUM> are internally threaded anchors <NUM>. The anchors <NUM> receive the alignment screws <NUM> which extend through the slotted openings <NUM> of the bracket <NUM> and the rectangular-shaped openings <NUM> of the movable blade <NUM> for threaded engagement with the threaded anchors <NUM> of the slider <NUM> to secure the slider <NUM>, the movable blade <NUM> and the bracket <NUM> relative to each other. The slider <NUM> further includes one or more, e.g., three protrusions <NUM> on each of its upper and lower surfaces.

As best depicted in <FIG>, the stationary blade <NUM> includes cutting teeth <NUM> defining an outer cutting edge. The stationary blade <NUM> also includes a recess <NUM> which receives the slider <NUM>. The slider <NUM> reciprocates within the recess <NUM> upon reciprocating movement of the movable blade <NUM> and the bracket <NUM>. The protrusions <NUM> on the upper and lower surfaces of the slider <NUM> minimize the areas of contact relative to the surfaces of the stationary blade <NUM> defining the recess <NUM> to reduce surface area contact and facilitate sliding movement of the slider <NUM> within the recess <NUM>. The stationary blade <NUM> further includes two large openings <NUM>. The openings <NUM> receive fasteners or screws <NUM> utilized to secure the stationary blade <NUM> to the handle <NUM>.

Referring now to the perspective view in partial cross-section of <FIG>, the eccentric rotating shaft <NUM> coupled to the one or more drive shafts <NUM> of the drive mechanism <NUM> (<FIG>) is shown disposed within the two opposed vertical walls <NUM> of the bracket <NUM>. Rotation of the eccentric shaft <NUM> causes the bracket <NUM> to reciprocate and/ or oscillate with the connected movable blade <NUM>. Also depicted in <FIG> are the alignment screws <NUM> which couple the bracket <NUM>, the movable blade <NUM> and the slider <NUM>.

With reference to <FIG>, the operation of the hair cutting system <NUM> including the hair cutter <NUM> and the adjustment tool <NUM> will now be discussed. <FIG> is a view similar to the view of <FIG>, and depicts a fully displaced condition of the movable blade <NUM> and the stationary blade <NUM>. In the fully displaced condition, the outer blade edges 70a of the cutting teeth <NUM> are in their maximum displaced condition represented by gap "g1" relative to the outer blade edges 88a of the cutting teeth <NUM> of the stationary blade <NUM>. Compare with <FIG> where the outer blade edges 70a, 88a are in the closed or approximated condition represented by gap "g2". To adjust the gap, or relative positioning of the movable blade <NUM> and the stationary blade <NUM>, the driver <NUM> is removed from the adjustment tool <NUM> as depicted in <FIG>. In embodiments, the driver <NUM> may be removed from the adjustment tool <NUM> without removal of the adjustment tool <NUM> relative to the cutting blade assembly <NUM>. In other embodiments, the adjustment tool <NUM> may be removed to permit removal of the driver <NUM>. The driver <NUM> is utilized to loosen both alignment screws <NUM>. It is noted that the presence of the strut <NUM> displaces the alignment screws <NUM> a sufficient distance from the handle <NUM> such that the operator can readily access the alignment screws <NUM> with the driver <NUM> without the need to first remove the blade assembly <NUM> from the handle <NUM>. Thereafter, the adjustment tool <NUM>, if previously removed, is positioned onto the cutting blade assembly <NUM> with the cutting blade assembly <NUM> being at least partially received within the spacing <NUM> of the adjustment tool <NUM> (<FIG>). As best depicted in <FIG>, the recess <NUM> defined within the proximal wall 24a of the adjustment tool <NUM> receives the strut <NUM> in a close tolerance fit. More specifically, the internal dimension "d1" (<FIG> and <FIG>) of the recess <NUM> in the proximal wall 24a of the adjustment tool <NUM> approximates the width "w1" of the strut <NUM> (<FIG>) whereby the corresponding interior wall surfaces 25a, 25b defining the recess <NUM> of the adjustment tool <NUM> and the outer walls 46a of the strut <NUM> are in contacting relation. As also shown, the upper surfaces <NUM> of the proximal wall 24a of the adjustment tool <NUM> engage the lower surface 58a of the movable blade <NUM>, i.e., on both sides of the movable blade <NUM>. To selectively close the gap between the blade edges 70a, 88a of the cutting teeth <NUM>, <NUM>, the adjustment tool <NUM> is advanced upwardly in the longitudinal direction of the directional arrows "m" of <FIG> and <FIG> such that the upper surfaces <NUM> of the of the adjustment tool <NUM> and the lower surface 58a of the movable blade <NUM> cause the movable blade <NUM> to move upwardly closing the gap between the outer blade edges 70a, 88a of the movable blade <NUM> and the stationary blade <NUM>. Due to the cooperative configurations of the strut <NUM> and the internal recess <NUM> of the adjustment tool <NUM>, the movable blade <NUM> is prevented from tilting, angulating, rotating etc. and moves directly linearly with respect to the stationary blade <NUM>. Thus, the blade edges 70a, 88a of the respective movable and stationary blades <NUM>, <NUM> remain in their parallel relation during and after adjustment of the movable blade <NUM>. This ensures that the cut or trim of the hair is linear and consistent. During longitudinal movement of the movable blade <NUM>, the alignment screws <NUM> traverse the elongated openings <NUM> of the bracket <NUM> (<FIG>) and the anchors <NUM> traverse the elongated outer rectangular-shaped openings <NUM> of the movable blade <NUM> (<FIG>). The alignment screws <NUM> may be tightened at any time to secure the relative positions of the movable blade <NUM> and the stationary blade <NUM>. It is to be appreciated that the movable blade <NUM> may be adjusted to a plurality of select positions relative to the stationary blade <NUM> between the fully displaced condition and the approximated condition and the adjustment screws <NUM> to selectively adjust the length of cut as desired.

With the movable blade <NUM> and the stationary blade <NUM> in their desired positions, the hair cutter <NUM> may be activated to cause reciprocating movement of the movable blade <NUM> (in the horizontal direction of directional arrow "b" (<FIG>) to cut, trim or shave hair.

Thus, the hair cutter system with the adjustment tool <NUM> in cooperation with the strut <NUM> ensure that the movable blade <NUM> is arranged in its intended aligned position after each adjustment. Although in exemplary embodiments, the aligned position is described as inclusive of the cutting edges of the movable blade <NUM> and the stationary blade <NUM> being in parallel relation, as a direct linear movement of the movable blade <NUM> relative to the stationary blade <NUM>, it is to be appreciated that other arrangements are envisioned as well. Moreover, it is envisioned that the cutting edges may be obliquely arranged with each other if such arrangement is the intended orientation of the blades. Otherwise stated, blades of a cutting blade assembly are not aligned if subsequent to adjustment of the relative positioning of the blades, the blades are mistakenly or undesirably askew from their intended orientation and use. In certain instances, an askew orientation of the blades may include an angulation or undesired orientation of one blade relative to another.

Furthermore, although described in terms of the movable blade <NUM> being longitudinally adjustable, it is within the scope of the present disclosure that either or both blades <NUM>, <NUM> may be longitudinally movable relative to each other.

Claim 1:
A hair cutting system, comprising:
a handle defining a longitudinal axis;
a strut mounted to the handle;
a hair cutting blade assembly coupled to the strut, the cutting blade assembly including:
a stationary blade defining cutting teeth having blade edges;
a movable blade defining cutting teeth having blade edges and capable of reciprocal movement relative to the stationary blade in a horizontal direction, the movable blade and the stationary blade being movable relative to each other in a longitudinal direction to adjust a longitudinal position of the movable blade relative to the stationary blade to selectively vary a distance between the blade edges of the stationary blade and the blade edges of the movable blade; and
a releasable lock to selectively lock and release the stationary blade and the movable blade with respect to each other in the longitudinal direction,
characterized in that the hair cutting system further comprises:
an adjustment tool mountable relative to the cutting blade assembly and operatively engageable with the movable blade, the adjustment tool and the strut correspondingly configured such that longitudinal movement of the adjustment tool imparts corresponding longitudinal movement of the movable blade to facilitate adjustment of the longitudinal position of the movable blade relative to the stationary blade.