Patent Application
20090119932
The present invention relates to a curved and toothed cutting blade for a trimmer and a grinding wheel for manufacturing said cutting blade.
Conventional toothed cutting blades for trimmers are straight and are manufactured by means of grinders. A typical grinder has a grinding wheel which comprises a plurality of axially spaced circular grinding disks connected together by a rotatable shaft passing through the centers of the respective grinding disks. The teeth of the blade are formed and sharpened by grinding the blade against the grinding wheel. The manufacturing process is simple and of low cost. However, such grinders can only manufacture straight cutting blades but not curved cutting blades.
Curved cutting blades are preferred for trimmers as it is ergonomic to make easier and faster adjustments to hair length according to the curvature of a portion of a body surface, for example, a human head. As illustrated in
In view of the aforesaid disadvantages now present in the prior art, the object of the present invention is to provide a kind of the curved and toothed cutting blades for trimmers which can be efficiently manufactured by simply grinding against a grinding wheel and is thus susceptible of low manufacturing costs.
To attain this, the present invention generally comprises a curved and toothed cutting blade for a trimmer comprising a base body having at least a connecting member for mounting onto a trimmer and a longitudinal cutting edge on one side which is symmetrically concave downward and has teeth, wherein the curve of the cutting edge is in the form of a segment of the interior of a circular arc of a lens with the two interior angles of any teeth not having different degrees of angle and the dent in between any two teeth being not perpendicular to the base pitch of the tips of the two teeth and slanted towards the center point of the curve of the cutting edge.
The curve of the cutting edge corresponds approximately to the curvature of a portion of a body surface such as a portion of a human head so that the cutting blade can fit the surface curvature of a body surface such as a human head to be trimmed, and it is therefore ergonomic to make easier and faster adjustments to hair length according to the curvature of the portion of the body surface. After trimming, the hair remaining on the body surface can be of substantially identical length, thereby creating a tidy cut which is very difficult to be achieved by a conventional straight toothed blade.
The present invention further provides a grinding wheel for manufacturing said cutting blade, wherein the grinding wheel is in the form of a lens with the two endpoints truncated with diameter being the largest in the middle and gradually decreasing towards the two ends and the surface of which has grooves of sizes and shapes which correspond to the sizes and shapes of the teeth of the cutting blade.
The grinding wheel may comprise a one-piece tool with the grooves being cut onto its surface and a rotatable shaft passing through its center.
Alternatively, the grinding wheel may comprise a plurality of axially spaced circular grinding disks with the alternate disks being of shorter diameters and all grinding disks being connected together by a rotatable shaft passing through the centers of the respective grinding disks, and the alternate disks of shorter diameters forming the grooves of the grinding wheel.
The grinder with the grinding wheel of the present invention operates in the same way as a conventional grinder does for manufacturing straight toothed cutting blades for trimmers known in the art. The curve and the teeth of the cutting blade are formed and sharpened by grinding the blade against the grinding wheel. The manufacturing process is simple and of low cost.
Further objects, features, and advantages of the invention will become more apparent from the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification. It should be understood, however, that the description and the specific example while representing the preferred embodiment is given by way of illustration only.
The present invention is further described in detail with the following embodiment and the accompanying drawings.
As illustrated in
As illustrated in
The grinding wheel 2 is to be installed onto a grinder and the grinder operates in the same way as a conventional grinder does for manufacturing straight toothed cutting blades for trimmers known in the art. The grinder with the grinding wheel 2 of the present invention can manufacture the curved and toothed cutting blade 1 which can be mounted onto a trimmer for trimming. The curve and the teeth 13 of the cutting blade 1 are formed and sharpened by grinding the blade 1 against the grinding wheel 2. The manufacturing process is simple and of low cost.
It is ergonomic to make easier and faster adjustments to hair length according to the curvature of the portion of the body surface. The user may simply move the trimmer in a direction that the cuffing edge 12 moves in parallel along the curvature of a portion of a body surface such as a human head to be trimmed. The hair on that part of the body will be trimmed and the hair remaining on the body part is of substantially identical length, thereby creating a tidy cut which is very difficult to be achieved by a conventional straight toothed blade.
The above embodiment is a preferred embodiment of the present invention. The present invention is capable of other embodiments and is not limited by the above embodiment. Any other variation, decoration, substitution, combination or simplification, whether in substance or in principle, not deviated from the spirit of the present invention, is replacement or substitution of equivalent effect and falls within the scope of protection of the present invention.
