A one-piece plastic disposable razor having structure which insures safe and efficient blade geometry while lending itself to high-speed mass production methods.

BACKGROUND OF THE INVENTION 
The present invention relates to disposable razors and in particular to low 
cost single-edge disposable razors. 
The invention also relates to one-piece razors where all elements of the 
razor are plastic save the metallic razor blade. Thus, the language 
"one-piece" relates to all elements of the razor except the blade or 
blades, as the case may be. 
A prior art razor over which the present invention is an improvement is 
disclosed and described in U.S. Pat. No. 3,154,852 issued Nov. 3, 1964, to 
E. B. Westlake, Jr. The '852 reference shows a one-piece razor with a 
replaceable double-edge blade. 
SUMMARY OF THE INVENTION 
A particular feature of the present invention is the provision of a low 
cost disposable plastic razor. 
A further feature of the invention is the provision of a razor of the above 
general class which includes structure for insuring the integrity and 
preservation of so-called blade geometry. 
The language "blade geometry" is intended to relate to the optimum position 
of the blade edge relative to the razor guard bar and the razor cap which 
must be achieved and preserved to insure safety. 
It is a further feature of the invention to provide a low cost one-piece 
plastic disposable razor susceptible of manufacture by means of high-speed 
mass production methods while maintaining the integrity and continuous 
quality of blade geometry. 
A razor embracing certain features of the present invention may comprise 
two basic plastic elements, one of said elements defining a handle, the 
other of said elements defining a cap, hinge means connecting both 
elements to facilitate relative rotation of said elements from a first or 
open position to a second or closed position and latch means for retaining 
the elements in the closed position with a single blade having a single 
cutting edge sandwiched therebetween.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIGS. 1, 2 and 3, a one-piece plastic razor comprising two 
basic elements indicated generally by the reference numerals 10 and 15 
includes a handle 11 having a pair of spaced ribs or fins 12 and 13 each 
terminating in support elements or shoulders 14 and 16 having coplanar top 
surfaces 17 and 18. That is, surfaces 17 and 18 define a plane. 
Shoulders 14 and 16 are each formed with notches 19 and 21 and slots 22 and 
23. 
The basic element 15, hinged to the basic element 10 by hinges 31 and 32, 
includes a razor cap 26 and a guard bar 27 connected to cap by ribs 28 and 
29. 
The elements 10 and 15 and the hinges 31 and 32 are cast or molded of 
plastic material so as to define a single piece-part. 
The element 15 is formed with a pair of projections or protuberances 
defining lugs 33-34 and claws 36 and 37. 
The lugs 33-34 are received within and mate with notches 19 and 21 
respectively when the element 15 is rotated from the open or first 
position of FIG. 1 to the closed or second position of FIG. 2. 
At the same time the claws 36 and 37 are received within and make a snap 
fit with slots 22 and 23 to retain the two basic elements in the closed 
position. 
As is apparent in FIG. 1, when the basic elements 10 and 15 are in the open 
position, a single blade 38 having a single edge 39 is secured to the cap 
26 by upsetting plastic rivets 41--41 in well-known fashion. 
Obviously two blades could be so secured with an appropriate spacer 
therebetween if desired. 
Thus, in the succeeding claims, reference to a "blade" or a "single blade" 
is intended to include one or more blades. 
The planar surface generated by the top surfaces 17 and 18 in combination 
with the cooperation between lugs 33-34 and mating notches 19 and 21 are 
very important elements of this invention. These members control and 
insure good blade geometry. 
It is well known that blade edge exposure, i.e., blade geometry, is 
critical to an efficient, safe shave. 
That is, too much edge exposure is unsafe and too little is inefficient. 
Since the hinges 31-32 are flexible and of relatively light or thin 
construction, they cannot be relied upon to place the blade upon the 
surfaces 17 and 18 in the correct position relative to handle 11. 
The planar surface generated by fairly extensive top surfaces 17-18 and the 
locking effect of the lugs 33-34 received in notches 19 and 21 insures 
good, safe and efficient blade geometry from razor to razor while leading 
itself to high-speed mass production methods. 
It is anticipated that a wide variety of modifications and design changes 
may be devices in the present invention without departing from its spirit 
and scope. 
For example, the fins 12 and 13 may be individually connected to the medial 
portion of the handle 11 by a "living" hinge so that the handle is molded 
flat and thereafter the fins 12 and 13 are rotated to the position of 
FIGS. 1 and 2.