RU85114U1 - SAFETY RAZOR BLADE BLOCK - Google Patents

Abstract

A safety razor blade unit comprising a plurality of elongated blades with cutting edges forming a shaving surface and having two attachment points to the supporting elements, characterized in that the blades have a smoothly curved cutting edge and a smoothly curved supporting element, the blades having a third fulcrum in it the central part with positioning springs, the shape of the cutting edge, representing a part of a circle with a radius, is determined by the formula:! Rinc = kL,! where Rizg is the radius of bending of the blade; ! k is the proportionality coefficient equal to 4 ÷ 5; ! L is the length of the chord of the curve with a radius of Rinc.

Description

The invention relates to safety razors having blade units with a plurality of blades with cutting edges.

Known razor (see RF Patent No. 2336156, B26B 21/22, 2008) comprising a razor block and a body with a recess. The razor block comprises a plurality of elongated metal blades with cutting edges, first and second plastic blocks. Smooth cutting edges of these metal blades form a shaving surface. Metal blades have first and second longitudinal ends. Moreover, the first and second longitudinal ends are attached respectively to the first and second plastic blocks with the formation of a single node. In this case, the metal blades are attached to each other at the ends. The razor block is fixed in said razor recess.

A drawback of the razor design is that metal blades with longitudinal ends have only two points of support at the ends, and also the smooth cutting edge of the metal blades does not allow to keep the angle of installation of the blades to the shaving surface stable.

A known razor adopted for the prototype (see RF Patent No. 2331508, B26B 21/22, 2008), comprising a razor block and a body with a recess. The razor block contains many smooth elongated metal blades with cutting edges. The cutting edges of these metal blades form a shaving surface. Metal blades have first and second longitudinal ends. Moreover, the first longitudinal ends are connected to each other by the first welded joints, and the second longitudinal ends are connected to each other by the second welded joints. In this case, metal blades are fixed only at the first and second longitudinal ends.

The disadvantage of the above design is that the smooth cutting edge of the blade allows you to cover a small cutting surface of the hair, and the method of fastening the blades with two points of support leads to a significant change in the angle of the cutting edge to the work surface, which is especially noticeable with a blunt blade - as a result, the hair does not cut, and "Tearing up."

The objective of the proposed device is to create a blade unit that provides easy and less irritating shaving while covering a larger surface of the hair with the cutting edge of the blade.

The technical result is achieved in that the safety razor blade unit containing a plurality of elongated blades with cutting edges forming a shaving surface and having two attachment points to the supporting elements, the blades have a smoothly curved cutting edge and a smoothly curved supporting element, the blades having a third fulcrum in its central part with positioning springs, the shape of the cutting edge, representing a part of a circle with a radius, is determined by the formula:

R _izg = k · L,

where R _izg - the radius of the bend of the blade;

k is the proportionality coefficient equal to 4 ÷ 5.

L is the length of the chord of the curve with a radius of R _ex .

The essence of the utility model is illustrated by figures, where in Fig.1 shows the mounting of the blades in the cassette, Fig.2 shows the cross-sectional shape of the blade.

The blade unit contains a plastic cartridge case 1, positioning slots 2, holding elements 3, smoothly curved blades 4, blade holders 5, fixing tabs 6, positioning springs 7. The smoothly curved blade 4 is secured in the cartridge case 1 by holding the fixing tabs 6 in grooves 2 by holding elements 3 and pressed by positioning springs 7 to the holders of smoothly curved blades 5. The cutting edge of the blade 8 is connected to a z-shaped base having a rib 9 for fixing by the holder 8.

The configuration of the bending of the blade in shape is taken as part of a circle with a radius calculated by the formula:

R _izg = kL

where: R _izg - accepted for the blade bending radius;

k is the proportionality coefficient equal to 4 ÷ 5.

L is the length of the chord of the curve with a radius of R _ex .

The smoothly curved shape of the cutting edge allows you to reduce the force for cutting the hair when shaving due to the movement of the blade at a slight angle to the hair being cut, while increasing the contact surface of the blade with the body.

The installation angle of the smoothly curved cutting edge with respect to the vertical axis is 110-115 °. The value of this angle is due to the geometry of the cutting edge of the blade, exceeding the value of the angle will reduce the efficiency of shaving.

The presence of a third fulcrum makes it possible to redistribute the forces arising from cutting hair from torsion to tensile forces, which makes it possible to keep the blade angle to the shaving surface stable, which makes shaving easier and less irritating.

Claims (1)

A safety razor blade unit comprising a plurality of elongated blades with cutting edges forming a shaving surface and having two attachment points to the supporting elements, characterized in that the blades have a smoothly curved cutting edge and a smoothly curved supporting element, the blades having a third fulcrum in it the central part with positioning springs, the shape of the cutting edge, representing a part of a circle with a radius, is determined by the formula: R _izg = k · L, where R _izg - the radius of the bend of the blade; k is the proportionality coefficient equal to 4 ÷ 5; L is the length of the chord of the curve with a radius of R _ex .