Not applicable
Not applicable
1. Field of Invention
This invention relates to an electric shaving device having a new shaving mechanism and mechanical structure to provide comfortable hair shaving with minimum skin irritation and convenient maintenance of the device.
2. Background and Prior Art
Electric shavers are convenient and widely used, however, their hair shaving mechanisms have inherent short comings. Basically, most existing electric razors use a hair-chopping mechanism. When a cutting edge hits a hair stem caught in a hole of a shaving screen, it pulls hair up and chops off or tears off the hair. This cutting mechanism irritates skin and can result in an uncomfortable skin rash for sensitive skins.
There are many existing electric shavers with variety of cutting edge designs, however, the basic mechanisms are all similar. For some recent examples, Kameoka, etal. (U.S. Pat. No. 6,951,056) described a cutting edge having a slightly broad surface that contacts with an outer cutter, Wong (U.S. Pat. No. 6,826,835 B1) described a 2-head shaver with a similar hair cutting mechanism to others, Shalev, et al. (U.S. Pat. No. 6,825,445) described a cutting mechanism using heating elements with a complex heat control system, Uchiyama, et al. (U.S. Pat. No. 6,823,590) described rotary cutting elements, Iwashita, et al (U.S. Pat. No. 6,789,322) described a switching system for moving the shaving head up/down with a similar cutting mechanism, Oswald (U.S. Pat. No. 6,675,480) described oscillating cutting elements and a shearing head, Gerasimov , et al used multiple rotting circular cutting elements having a shallow cup shape under a flat circular screen, Zucker (U.S. Pat. No. 6,442,840 B2) described a cutting edge adopted on a roller under a half circular screen, Ilkhanov (U.S. Pat. No. 6,154,962) described cutting elements having a flat elliptical shape rotating by a center shaft under half circular screen head, Tezuka, et al (U.S. Pat. No. 5,678,313) described a triple headed shaver, Ascoli (U.S. Pat. No. 4,115,920) used all flat and circular shaped cutting elements arranged vertically to and under curved cutting screen, and they are oscillating to each other horizontally, Yamada, et al (U.S. Pat. No. 4,058,749) also used basically flat semi-circular cutting elements and half circular screen, Meyer (U.S. Pat. No. 3,947,961) used multiple cutting element arranged vertically under a curved screen, Shoemaker (U.S. Pat. No. 3,143,797) described a cylindrical shearing element having multiple small triangular openings and multiple vertically arranged cutting elements which rotate and reciprocate, Frith (U.S. Pat. No. 3,027,635) described a helical cutting elements rotating in a cone shaped or cylindrical shape screen, Page (U.S. Pat. No. 2,440,114) described a rotating cutting elements under half circular outer cutting element, Hall (U.S. Pat. No. 2,423,595) described multiple circular cutting discs by a motor and frictional wheel mechanism under a round comb shaped outer cutting head, and Jepson (U.S. Pat. No. 2,220,800) described a device has partially perforated and curved cutting head which oscillates slowly and rotting inner cutting elements. These prior arts, all use a similar hair pulling and chopping mechanism. Also, most conventional electric shavers are bulky and the effective shaving head surface is limited, and cleaning the shaving head is cumbersome.
The present invention does not use a hair chopping mechanism, instead it uses a hair-slicing mechanism which is similar to blade shaving. It gives users a more comfortable and smoother hair shaving experience and avoiding skin irritation.
Several additional objectives and advantages are:
The present electric razor slices hair off like a blade shaving and is comprised of a cylindrical shaving screen head and a set of knives that moves in a 3-dimensionally elliptical motion on the inner surface of the cylindrical shaving screen.
In the drawings, closely related parts of a figure have the same part number with different alphabetical suffixes.
11 Shaving screen
12 Shaving knife having flat and dual cutting edges longitudinally
12
a Pins on knife
13 Shaving knife holder
14 Moving shaft, L-shape
15 Shaving screen adopter
16 Rotating cup
16
a Moving shaft anchoring position
17 Motor
18 Power source (battery)
19 Main body
20 Switch
Head of a device
Small spring
The preferred embodiment of the present invention is illustrated in
When the motor (17) turns, the rotating cup (16) in the head of the device (21) rotates and the short arm of the moving shaft (14) anchored on the inner wall of the rotating cup turns and the long arm of the moving shaft (14) rotates and slides up/down, (i.e. reciprocation) because of the angled orientation of the long arm of the moving shaft (14) from the rotation axis of the rotating cup (16). The reciprocating distance is proportional to the diameter, d of the rotating cup (16) and the angle of the long arm of the moving shaft (14) with respect to the rotating axis of the rotating cup (16). The approximate relationship between the reciprocating distance (D), the angle (A) between the shaving screen and the motor axis and the cup diameter (d) can be expressed as: D−d tan A. Accordingly, the shaving knife set moves in a rotation and reciprocation motion simultaneously, which causes the shaving knives to move 3-dimensionally elliptical motion. The shaving knife surface is sliding on the inner surface of the cylindrical screen in close contact by means of small spring (22).
Thus, this invention provides an effective and comfortable hair-shaving device in wet or dry environments with minimum skin irritation. The device can be cleaned by simple rinsing with running water. The operation is smooth and quiet. It is also slim and compact with ergonomic holding handle for easy use and carrying.
While the above description contains many specifics, these should not be construed as a limitation on the scope of the invention, but rather as an example of one preferred embodiment thereof. Many other variations and uses are possible. For example, the simultaneous rotation/reciprocation mechanism in this device can be generated by a cylindrical cam mechanism, and the mechanism can be applied to other devices such as a toothbrush, rod saw, etc. To increase the rotation power, a gear head motor can be used and a rechargeable power source can be adopted. Accordingly, the scope of the invention should be determined not by the embodiment illustrated, but by the appended claims and their legal equivalent.
This application claims the benefit of provisional patent application Ser. No. 60/850,989, filed Oct. 11, 2006 by the present inventor.
Number | Name | Date | Kind |
---|---|---|---|
2219090 | Henderson | Oct 1940 | A |
2220800 | Jepson | Nov 1940 | A |
2355672 | Page | Aug 1944 | A |
2423595 | Hall | Jul 1947 | A |
2440114 | Page | Apr 1948 | A |
3027635 | Frith | Apr 1962 | A |
3045344 | Cholet | Jul 1962 | A |
3143797 | Shoemaker | Aug 1964 | A |
3947961 | Meyer | Apr 1976 | A |
4038749 | Yamada et al. | Aug 1977 | A |
4115920 | Ascoli | Sep 1978 | A |
5678313 | Tezuka et al. | Oct 1997 | A |
6154962 | Ilkhanov | Dec 2000 | A |
6442840 | Zucker | Sep 2002 | B2 |
6584691 | Gerasimov et al. | Jul 2003 | B1 |
6675480 | Oswald | Jan 2004 | B2 |
6789322 | Iwashita et al. | Sep 2004 | B2 |
6823590 | Uchiyama et al. | Nov 2004 | B2 |
6825445 | Shalev et al. | Nov 2004 | B2 |
6826835 | Wong | Dec 2004 | B1 |
6951056 | Kameoka et al. | Oct 2005 | B2 |
Number | Date | Country | |
---|---|---|---|
60850989 | Oct 2006 | US |