BACKGROUND OF THE INVENTION

The present invention relates to personal care appliances and, more particularly, to electrically powered hair cutting devices.

Description of Related Art

Electrically-powered hair cutting devices commonly referred to as

"clippers" or "shavers", depending on specific use, typically comprise an electric motor, a movable blade that is caused to move by output from the motor, and a stationary blade that is juxtaposed adjacently to the movable blade so that, together, the blades cut hair by shearing action because both blades have teeth patterns and hair is positioned between valleys of the teeth pattern and thus sheared when one blade moves. Known electric hair cutting devices are typically one of two types: straight, single cutting blade assembly where a linear fixed blade and a linear movable blade are used; and foil assembly comprising one or more rotating blade assemblies within a curved "foil" that serves as a stationary blade. Both types of hair cutting devices required a user to hold the device at a specific angle relative to the body part being trimmed or shaved, whereby in some instances it is difficult to maintain uniformity in angle resulting in lack of uniformity in hair cutting length. Also, both types of hair cutting devices do not provide means to collect the cut hair pieces, and instead cause them to fall or be thrown in various directions.

OBJECT OF THE PRESENT INVENTION

It is an object of the present invention to provide a hair cutting device that enables a user to consistently obtain uniform cutting length and to collect cut hair pieces.

These an other objects are achieved by the present invention disclosed herein. SUMMARY OF THE INVENTION

According to the present invention, a hair cutting device comprises a housing, an electric motor positioned in said housing, an electrical source for powering the motor (either a battery, a cord for attaching to an external source, or both), a stationary blade of ring-shaped configuration, a movable blade of ring- shaped configuration, and a cutting guide for contacting the body during cutting to control the length of the cut, said cutting guide being adjustable for setting different cutting lengths.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 A is a top, perspective view of a preferred embodiment of the present invention.

Figure 1 B is a bottom, perspective view of a preferred embodiment of the present invention.

Figure 2 is a side, cross-sectional view of a preferred embodiment of the present invention.

Figure 3 is a partial, phantom, perspective, top view of a preferred embodiment of the present invention.

Figure 4A is a perspective view of a preferred embodiment moving blade component of the present invention.

Figure 4B is a perspective view of a preferred embodiment stationary blade component of the present invention

Figure 4C is a perspective view of a preferred embodiment of each of the moving blade component and the stationary blade component of the present invention.

Figure 5A is a perspective view of a preferred embodiment of the blade assembly of the present invention.

Figure 5B is a partial, side, cross-sectional view of a preferred

embodiment of the blade assembly of the present invention.

Figure 6A is a side, cross-sectional view of a preferred embodiment of the present invention shown in use on a user's head in a side view. Figure 6B is a side view of a user's head having its hair cut using and in accordance with a preferred embodiment of the present invention.

Figure 7 A is a side, cross-sectional view of a preferred embodiment of the present invention shown in use on a user's head in a side view.

Figure 7B is a partial, side, cross-sectional view of a preferred

embodiment of the present invention shown in use on a user's head in a side view.

Figure 8 is a perspective, bottom view of a preferred embodiment of the present invention.

Figure 9 is an inverted, perspective, bottom view of a preferred

embodiment of the present invention.

Figure 10A is a perspective view of a prior art hair cutting device.

Figure 1 OB is a perspective view of a prior art hair cutting device having a hair clipper attachment according to a second preferred embodiment of the present invention.

Figure 1 OC is a partial, perspective view of a prior art hair cutting device having a hair clipper attachment according to a second preferred embodiment of the present invention.

Figure 1 OD is a partial, perspective view of a prior art hair cutting device having a hair clipper attachment according to a second preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE PRESENT INVENTION

Referring to Figs. 1 - 1 OD, a hair cutting device 1 according to a preferred embodiment of the present invention comprises a housing 2, an electric motor 3 positioned in said housing 2, an electrical source (not shown) of a type known to those skilled in the art for powering the motor (either a battery, a cord for attaching to an external source, or both), a stationary blade 4 of ring-shaped configuration, a movable blade 5 of ring-shaped configuration, and a cutting guide 6 for contacting the body during cutting to control the length of the cut, said cutting guide being adjustable for setting different cutting lengths.

A power switch 7 for turning the device on and off, causing the movable blade to move, is located on the top of the housing 2. An electrical power adapter socket 8 is provided on the outside of the housing 2 in order to receive an electrical cord (not shown) of a type known to those skilled in the art in order to deliver electrical energy to the motor 3. Alternatively, the electrical cord can deliver energy to a battery pack (not shown) housed in the housing 2. An open chamber 9 is formed within the circular cutting guide 6. The upper portion 10 of the housing 2 is circular and is of a larger diameter than a central portion 11 of the housing 2, which is also circular, in order to enable a user's fingers to comfortably grasp the device 1 by placing some or all of the fingers and the thumb at or near the central portion 1 1. A power indicator light 12, in the form of an LED, is located on the upper portion 10.

The motor 3 has an output shaft 13 that delivers rotational energy from the motor to a transmission link 14. The transmission link 14 is eccentrically mounted to the output shaft 13 via a mount 16 to convert its rotational movement to oscillating, linear motion. A conversion gear 15 drives the movable blade 5 in oscillating movement, along a rotational path, so that the movable blade 5 moves relative to the stationary blade 4. The movable blade 5 is attached to the conversion gear 15 via a blade holder 17. Because the blades 5, 4 are adjacent to each other, and because each has cutting teeth, hair that is positioned between valleys of the teeth pattern is cut by shearing action between the two blades 5, 4. The transmission link 14 is connected to the conversion gear 15 via a pin-and-slot type connection, of a type known to those skilled in the art, to convert the oscillating movement of the link 14 to movement in the desired plane to cause the blade holder 17 and the movable blade 5 to oscillate. The cutting blade holder 17 is mounted on an axle 19 so that it can rotationally oscillate with respect to the housing 2 and the stationary blade 4, which is fixed relative to the housing 2 by the distal end 20 of the housing 2. The blades 4, 5 are positioned near the opening of the open chamber 9. The open chamber 9 is adjacent to a widened cavity region 18 that is of a wider diameter than the opening of the chamber 9, thus enabling cup hair pieces to collect in the open chamber 9 and be generally held within until the user is ready to clean the chamber 9, thus preventing large amounts of hair from being dropped as occurs with conventional hair cutting devices.

A bearing assembly 21 supports the blade holder 17 for movement about the axle 19 and springs 22 provide downward bias on the blade holder 17 to impart pressure between the blades 4, 5 for increased cutting efficiency.

As shown in Figure 5B, the movable blade 5 has an S-shaped bend, in cross-section, for added strength and resistance to deformation. Similarly, the stationary blade 4 has a bend 24 in it for the same purpose. As shown in Figure 5A, the movable blade 5 has cutting teeth 25 facing concentrically inwardly from the inner diameter of the blade 5. Also shown in Figure 5A, the stationary blade 4 has cutting teeth 26 facing concentrically inwardly from the inner diameter of the blade 4.

Referring to Figures 6A, 6B, 7A and 7B the cutting device 1 is applied against a user's scalp 27 as shown in order to cut hair 28. The resulting cut hair 28, as shown in Figure 6B, is of uniform length so long as the cutting guide 6 is maintained at one setting. The guide 6 may be adjusted throughout a hair cutting session to achieve various lengths as shown in Figure 8, where twisting the guide 6 in the direction shown at arrow 29 will cause a camming action of the housing 2 relative to the guide 6 due to an angled slot 30 in which a pin (not shown) of a type known to those skilled in the art is used to achieve height adjustment.

Figure 9 illustrates cut hair 28 being received in the open chamber 9 as a result of cutting operation with the device 1. A user can manually empty the hair from the chamber when desired.

Figures 1 OA - 1 OD illustrate an alternative embodiment of the present invention. A conventional hair cutting device 31 may be fitted with a circular cutting attachment 32 according to the present invention. The cutting

attachment 32 is similar in form and function to the device 1 of the previous embodiment. While the attachment 32 has no motor of its own, it is adapted to attach via its attachment transmission member 33 to the oscillating output member 34 of the device 31. This enables the blade assembly 35 of the attachment 32 to function as similarly to the blade assembly of the previously described embodiment.

While the preferred embodiment of the present invention has been disclosed herein, it is understood that various modification can be made without departing from the scope of the presently claimed invention.