EDGE GRINDING MACHINE AND ITS APPLICATION IN THE MANUFACTURING OF
NAIL CUTTER/CLIPPER
Field of the invention:
The present invention relates to grinding of edges of the nail cutter/clipper during its
manufacturing, using the proposed edge grinding machine. Said edge grinding machine
is installed with motorized grinder for grinding the edges of the nail cutter/trimmer head
of the main body, particularly for effective grinding of the curved edges of said nail
cutter/trimmer head in single grinding step.
Background and object of the present invention:
Nail cutters are usually made of steel but can also be made of plastic and aluminum.
Two common varieties are the pliers and the compound lever type. All are common
household objects. Most nail cutters usually come with another tool attached, which is
used to clean the dirt out of nails. A nail trimmer often has a miniature file fixed to it to
allow rough edges of nails to be manicured. A nail file allows for removal of any excess
nail that is jagged or has been missed. Nail cutters occasionally come with a pocket
knife or a nail catcher. The nail trimmer consists of a head which may be concave or
convex.
Most common nail cutter/clipper in domestic use in these days is of compound lever
type cutters/clippers. The nail cutter/trimmer head is the sole of the product, wherein its
cutting/trimming edge is made very sharp. With time the sharpness of the edges
2
become ineffective for cutting/trimming the nail. Sometimes the edges get easily
damaged, mainly due to misuse or mishandling of the device. Further these edges of
the nail cutter/trimmer head lose their sharpness due to various manufacturing steps
involved, namely electroplating of the components and multi-time grinding. Sometimes,
certain nail cutter/trimmer heads are so shaped that it becomes difficult to grind the
edges uniformly and create very smooth long lasting sharp edges of the nail
cutter/trimmer. Therefore the industry is regularly trying to remove all existing defects
getting associated to the edges of the nail cutter/clipper heads of nail cutters/clippers,
utilizing available state of the art technologies available for the same purpose.
Object of the present invention is to perform very effective and economical edge
grinding operation towards sharpening of the edge of nail cutter/clipper head during
manufacture of the nail cutter/clipper, and to get rid of any kind of said edge related
defects.
Prime object of the present invention is to propose process for edge grinding of nail
cutter/clipper, particularly on the edge grinding machine being proposed herein.
Another prime object of the present invention is to propose an edge grinding machine is
installed with a motorized roller type grinder, wherein said grinder effectively grinds the
edges of nail cutter/trimmer head, preferably in single attempt/run therein.
Another object of the present invention is to propose strengthening of the material of the
nail cutter/clipper head and the main body as well stronger/tougher before performing
said grinding operation, particularly by the suitable heat treatment.
3
1*
Another object of the present invention is to propose such edges of the nail
cutter/clipper during its manufacturing, which after receiving the edge grinding treatment
on the proposed edge grinding machine herein, does not get affected adversely during
the final electroplating operation performed on all components of the nail cutter/clipper,
the assembled together.
Statement of the invention:
The present invention is intended to propose:
• process for edge grinding of nail cutter/clipper, particularly on the edge grinding
machine being proposed herein;
• an edge grinding machine, installed with a motorized roller type grinder, wherein
said grinder effectively grinds the edges of nail cutter/trimmer head, preferably in
single attempt/run therein;
• strengthening of the material of the nail cutter/clipper head and the main body as
well stronger/tougher before performing said grinding operation, particularly by
the suitable heat treatment; and
• such edges of the nail cutter/clipper during its manufacturing, which after
receiving the edge grinding treatment on the proposed edge grinding machine
herein, does not get affected adversely during the final electroplating operation
performed on all components of the nail cutter/clipper, the assembled together.
Description of the present invention:
The present invention generally discloses a novel edge grinding machine for nail
cutter/clipper, which grinds the edges of nail cutter/clipper head effectively and
4
1»
preferably in single run of the edge onto the grinder in such a manner that the proposed
grinding process yields long lasting sharp edges of the nail cutter/trimmer head. In the
present invention the main body of the nail cutter/clipper, its nail cutter/clipper head and
its various components thereof are preferably made from cold roll & close annealed
(CRCA) mild steel material, preferably by involving several operations towards
cutting/slotting, bending & shaping, edge grinding and electroplating etc.
The proposed edge grinding machine mainly comprises of a roller type grinder, wherein
the diameter of the grinder is equivalent to the size and curves created on the edges of
the nail cutter/trimmer head. Said grinder is electric motor operated and the grinding
operation using it is performed preferably manually. The frequency of rotation (RPM) of
the roller type grinder is adjustable and is so adjusted that the rotation of said functional
grinder becomes capable of grinding the edges of the nail cutter/trimmer head in single
grinding run. Thus the proposed machine yields sharp edges on both the segments of
the jaw of nail cutter/trimmer head, which is very smooth and uniform.
The nail cutter/clipper has nail cutter/trimmer head at one end of its main body, wherein
said head is shaped as an open jaw. Said jaw has two segments, upper and lower,
wherein said segments of the jaw are provisioned for clipping the nail between
themselves and trimming the nail thereafter.
In one preferred embodiment of these two segments are slightly curved/concave
inwardly such that the jaw can cover the nail properly for effective and safe
cutting/trimming thereof. Therefore, during grinding of such curved/concave shaped
edges of the pair of jaw segments of nail cutter/trimmer head, complications arise in
5
making uniform, equal and smooth grinding on both edges of both jaw segments of the
nail cutter/trimmer head.
Therefore in the said embodiment of nail cutter/trimmer, edge grinding operation is
performed on the proposed motorized edge grinding machine, using any one of two
optional ways of grinding:
(a) For one embodiment of said nail cutter/clipper, during its manufacturing, both the
jaw segments are pressed and clamped together and then both the edges of
these segments are subjected to simultaneous grinding. The closely pressed
pair of segments are kept in vertical position to the rotating grinder and a uniform
contact of edges are made with the rotating surface of the grinder, wherein the
curved/concave shaped edges of the jaw segments match with the
circumference of the rotating grinder. Further, after creating mutually matching
sharp edges on both the jaw segments of the nail cutter/trimmer head, any
further optional grinding around said edges/jaw segments can be performed.
(b) For another embodiment of said nail cutter/clipper, during its manufacturing as
an alternative grinding operation, both the edges of jaw segments are grinded
separately, keeping the jaw of the nail cutter/trimmer head in open condition,
followed by grinding them together towards making the grinding uniform therein.
After preparing all the components of said nail cutter/clipper, they are suitably
assembled and installed around a common lever. The complete and duly assembled
nail cutter/clipper device finally undergoes electroplating process towards coating the
surfaces of all components thereof for shine and protection against any rusting.
6
As the grinding on both the edges of said jaw of nail cutter/trimmer is carried out so
smoothly and uniformly, and the work-piece of the main body therein has already
received heat treatment towards enhancing toughness/strength, both the sharp edges
of said jaw receives one unique property: they do not get adversely affected by said
final electroplating operation, wherein said electroplating operation is performed in
controlled manner, very specific to the nail cutter/clipper proposed herein. Thus there is
no requirement of any final grinding of said edges of the jaw of nail cutter/trimmer head
of the main body therein. Optionally, in case there is very thicker electroplated metal
coating, the edges of said jaw of nail cutter/clipper may receive certain extent of outer
coating, which is of temporary nature and therefore to remove such unwanted coat,
second run of edge grinding may be performed.
Work-pieces of all the components of the present nail cutter/clipper device are obtained
by slotting them out from a metal sheet of certain uniform diameter. These work-pieces,
at one or another stage of their manufacturing, undergoes heat treatment, wherein said
work-pieces are heated uniformly for a particular period and thereafter cooled suddenly
below normal room temperature. Such heat treatment enhances the hardness and
toughness of the nail cutter/clipper components against any damage, mainly due to
abrasion or any mishandling of the said product.
Thus, before initiating the edge grinding of the both edges of the jaw of nail
cutter/trimmer head, the main body of said nail cutter/trimmer is subjected to
strengthening operations therein, particularly by the suitable heat treatment.
7
Scope of the invention:
Although the invention has been described with reference to specific embodiment, this
description is not meant to be construed in a limiting sense. Various modifications of the
disclosed embodiments, as well as alternate embodiments of the invention, will become
apparent to persons skilled in the art upon reference to the description of the invention.
It is therefore contemplated that such modifications can be made without departing from
the spirit or scope of the present invention as defined.

We claim:
1. Edge grinding machine and its application in the manufacturing of nail
cutter/clipper, wherein said edge grinding machine is installed with a motorized roller
type grinder, having its shape and diameter corresponding to the dimension and shape
of said pair of edges of nail cutter/trimmer head; and wherein said edge grinding
machine is characterized by its application in such a manner that:
the edges of the jaw of nail cutter/trimmer head of said nail cutter/clipper, gets
smooth and uniform grinded, preferably in single attempt/run therein;
and
the grinded pair of said edges of said jaw are subjected to controlled metallic
coating during final electroplating of the nail cutter/clipper and thus do not get
adversely affected thereof.
2. Edge grinding machine and its application in the manufacturing of nail
cutter/clipper, as claimed in claini 1, wherein the shape and dimension of said roller type
grinded is corresponding to and compatible to the shape and dimension of the pair of
edges of the jaw of nail cutter/trimmer of the said nail cutter/clipper.
3. Edge grinding machine and its application in the manufacturing of nail
cutter/clipper, as claimed in claim 1, wherein before undergo grinding operation, said
pair of edges of the jaw of nail cutter/trimmer of the said nail cutter/clipper are subjected
to heat treatment for strengthening and toughness against any abration.
4. Edge grinding machine and its application in the manufacturing of nail
cutter/clipper, as claimed in claim 1, wherein said grinder is characterized by:
9
V
Its shape and dimension corresponding to the shape and dimension of the edges
of said jaw of the nail cutter/trimmer head;
in an embodiment of nail cutter/clipper, preferably grinding the pair of edges of
said jaw of the nail cutter/trimmer head simultaneously; and
effectively grinds the edges of nail cutter/trimmer head in single attempt/run
therein, not requiring any secondary grinding after electroplating/coating various
surfaces of the nail cutter/clipper device.