Early Gillette Twist-To-Open patent
Patent US2004086
Invention Safety Razor and Blade
Filed Saturday, 14th July 1934
Published Tuesday, 4th June 1935
Inventor Nicholas Testi
Owner Gillette Safety Razor Company
Language English
CPC Classification:B26B21/32
- B26B21/32
Safety razors with one or more blades arranged transversely to the handle of the type carrying pivotally-mounted caps in razors involving double-edged blades - B
Performing Operations; Transporting - B26
Hand Cutting Tools; Cutting; Severing - B26B
Hand-Held Cutting Tools Not Otherwise Provided For - B26B21/00
Razors of the open or knife type; Safety razors or other shaving implements of the planing type; Hair-trimming devices involving a razor-blade; Equipment therefor - B26B21/08
Razors of the open or knife type; Safety razors or other shaving implements of the planing type; Hair-trimming devices involving a razor-blade; Equipment therefor involving changeable blades - B26B21/14
Safety razors with one or more blades arranged transversely to the handle - B26B21/30
Safety razors with one or more blades arranged transversely to the handle of the type carrying pivotally-mounted caps
For a full resolution version of the images click here
A PDF version of the original patent can be found here.
Parts not referenced in the text: None
Parts not referenced in the images: None
This invention relates to safety razors of the type in which a thin flexible blade is clamped in position for shaving between two blade-clamping members, such as a cap and guard. The invention includes within its scope a novel safety razor blade herein shown as adapted particularly for use in connection with the novel safety razor of my invention.
It will be understood that in using safety razors of this general type the satisfaction of the user depends in a large measure upon the accuracy with which the blade is located in the razor and the accuracy of its edge exposure. In locating the blade extremely fine measurements are involved and it is good practice to restrict the allowable variation or tolerance in edge exposure within a range of 0.004″. If the edge exposure of the blade is greater than is permitted by this allowance the safety razor becomes dangerous and the user is likely to cut himself. On the other hand, if the blade exposure is less than this allowance unsatisfactory shaving and pulling results. Manufacturing conditions made it difficult heretofore to hold the tolerances effecting blade exposure within the desired limits. The principal object of the present invention is to improve these conditions by rendering the operation of locating the blade in the razor more accurate and, in general, I attain the desired results by employing for this purpose cooperating, sharply defined surfaces or edges in the razor and in the blade which may be produced and located with a high degree of accuracy. In accomplishing this result I take advantage of the fact that it is easier under manufacturing conditions to shape and locate definite engaging edges of relatively small dimensions than it is to produce more extensive engaging edge contours of high accuracy. For example, a blade may be accurately located by providing it with short spaced engaging edges or shoulders and bringing such edges into abutting relation with corresponding stop lugs, since other portions of the blade may then be shaped for clearance and have no effect in positioning the blade. Thus, I overcome inaccuracies due to the necessity of allowing clearance for fit in a blade and to compensate for shrinkage in the tempering operation.
With respect to the razor itself, I contemplate cap and guard members arranged for opening or closing movement and mechanism for effecting such operation which is arranged to act through the blade itself as one link in the train and insure proper positioning of the blade before the closing of the razor. In this way I insure correct positioning of the blade before closing and entirely relieve the user of necessity for exercising any skill in locating his blade. The razor of my invention is so constructed as to insure that if the blade is presented at all to the razor it will be automatically located with the greatest possible accuracy through the medium of the most advantageous gauging surfaces, and without requiring any attention whatever on the part of the operator beyond the usual manipulations for opening or closing the razor. Indeed, I go one step further than this and insure that the razor cannot be closed at all unless the user has properly presented the blade to it. This is accomplished by including the blade itself as one element of the train of mechanism used to effect the clamping or closing movement of the razor. With this object in view an important feature of my invention consists in cooperating blade-clamping members connected for opening and closing movement and operating mechanism therefor including an element movable to a position in which closing is obstructed except when restrained from moving into such position by engagement of an apertured blade in the razor.
In one embodiment of my invention I provide an angularly movable blade-positioning bar which is moved in the razor closing operation to swing the blade and cause its gauging edges to engage suitably located blade stops in the razor. When this operation is effected the bar is locked in position and the closing mechanism is effective to carry out the closing operation. If, on the other hand, no blade is presented to the razor the blade-locating bar swings into a position to obstruct the subsequent closing movement of the cap.
These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof selected for purposes of illustration and shown in the accompanying drawings, in which,—
The guard member of the illustrated razor is in the form of an elongated bar
The razor is provided with a blade-supporting or carrying plate
An elongated blade-positioning bar
The cap herein shown comprises a pair of similar cap sections
In
In the blade shown in
The razor is shown in
If the user now desires to open the razor to remove or replace the blade
In comparing the two blades of
Having thus described my invention what I claim as new and desire to secure by Letters Patent is:—
1. A safety razor comprising a blade, cooperating blade-clamping members connected for closing and opening movement, and an element movable to prevent closing movement arranged to be rendered inoperative for this purpose by the blade itself.
2. A safety razor comprising an apertured blade, cooperating blade-clamping members connected for closing and opening movement, and operating mechanism therefor including an element movable to a position obstructing closing except when restrained by engagement with the aperture of the blade in the razor.
3. A safety razor having movable cap sections for flexing and clamping a blade in shaving position, and an operating train of mechanism for forcibly closing said sections including the blade as an element thereof.
4. A safety razor having movable cap sections for clamping a blade in shaving position, and an element movable to prevent clamping action of said cap sections arranged to be rendered inoperative for this purpose by the blade itself.
5. A safety razor comprising a blade having unsharpened internal gauging edges, cooperating blade-clamping members connected for opening and closing movement, blade-locating stops in the razor, and mechanism for closing said blade-clamping members operating to cause the blade to move its gauging edges to engage with said blade stops before said mechanism becomes effective to close the clamping members.
6. A safety razor comprising an apertured blade having internal gauging edges, cooperating blade-clamping members connected for opening and closing movement, spaced blade stops in the razor, and mechanism for closing said blade-clamping members including a blade-locating bar arranged to enter the aperture of the blade and to cause the gauging edges of the latter to engage with said blade stops before closing takes place.
7. A safety razor comprising a blade with an elongated aperture therein having defined gauging edges adjacent to each end, cooperating blade-clamping members connected for opening and closing movement, a blade-positioning bar movable angularly in the blade aperture and tending to cause the gauging edges of the blade to be advanced, and mechanism for closing the blade-clamping members controlled in its operation by said bar.
8. A safety razor comprising a guard member having a blade-shaping shoulder, a blade-carrying plate mounted on said guard member for vertical movement relatively thereto, cap sections carried by said plate, and an angularly movable blade-positioning bar movable vertically with said plate.
9. A safety razor comprising a guard member, a blade-carrying plate movable toward and from said member, cap sections movably connected to said plate, a blade-positioning bar movable with said plate, and mechanism for opening or closing the cap sections having an operative connection with said bar in all positions thereof.
10. A safety razor having a channeled guard plate, a blade-carrying plate movable up and down in the channel of the plate, cap sections operated by said plate, and an oscillating blade-locating bar movable with said plate.
11. A safety razor having a channeled guard plate, a blade-carrying plate movable up and down in the channel of the plate, cap sections operated by said plate, and an oscillating blade-locking bar movable with said plate, and blade-stop lugs on said plate for limiting the swing of said blade-locking bar in one direction.
12. A safety razor having cap and guard members, a blade-carrying plate movably mounted in the razor, an oscillatory blade-positioning bar arranged for limited movement on said plate, spring means binding at all times to elevate said plate, and mechanism acting positively to lower said plate when the blade-positioning bar is held against movement.
13. A safety razor having cap and guard members, a blade carrying plate having stops for holding a blade thereon against movement in one direction, an oscillatory blade-positioning bar on said plate, and mechanism acting to lower said plate when the blade-positioning bar is held against movement by a blade which engages it and said stops.
14. A safety razor having blade-clamping mechanism, including a threaded stem, an oscillatory blade-locating bar thereon, and an operating member including a nut arranged to screw down the clamping mechanism when turned by the user and when said blade-locating bar is held against turning by a blade in the razor.
15. A safety razor having a guard member, a cap member movably connected thereto, a blade stop, and mechanism for forcibly closing the cap member upon the guard to flex a perforated blade therebetween, including a blade-positioning bar arranged for transverse movement until arrested by engagement between the blade and said blade stop.
16. A safety razor having cooperating cap and guard members, a handle, a blade stop, and mechanism operated from the handle for forcibly closing said members upon an interposed perforated blade, including a blade-positioning member extending into the perforations of the blade and arranged for movement upon the guard member until arrested by engagement of the blade with its blade stop.
Nicholas Testi.