US2111215A

US2111215A - Lock

Info

Publication number: US2111215A
Application number: US169405A
Authority: US
Inventors: Edward N Jacobi
Original assignee: Briggs and Stratton Corp
Current assignee: Briggs and Stratton Corp
Priority date: 1937-10-16
Filing date: 1937-10-16
Publication date: 1938-03-15
Anticipated expiration: 1955-03-15

Description

E. N. .mcolsll 2,311,215

Loox v Filed oct. le, 1937 Patented Maf. 15, 193s UNITED sri* PATENT GFFICE VBriggs & Stratton Corporation, Milwaukee,

Wis., a corporation of Delaware Application October 16, 1937, Serial No. 169,405

8 claims.

This invention relates to improvements in locks and refers particularly to pin tumbler locks.

As disclosed in a copending application, Serial No. 141,713, filed May 10th, 1937, in some types of pin tumbler locks the cylinder is: assembled with the casing from the rear. This necessitates the provision of means to protect or guard the joint between the cylinder and its casing at its exposed front end toprevent the insertion of a thin feeler between the cylinder and the wall of the bore for the purpose of picking the lock.

The present invention is directed generally to this type of lock and has particular reference` to a specic application of this lock ywherein the construction is such that the outside diameter of the cap or other covering means used to protect the front end of the lock may not be larger than the diameter of the cylinder.

Another requirement of this specic; installation is that the key-Way be open to the bore of the casing so that the key will rest on the bore of the casing and receive support therefrom.

This invention therefore contemplates as one of its objects to provide an improved cap construction which meets these requirements in a simple and practical manner.

Inasmuch as the main body of the cap may not be larger than the diameter of the cylinder,

and as the keyway must break through this portion of the cap as well as the cylinder, it follows that the cap is necessarily weakened by its key opening, and to guard against bursting or tearing the cap durin-g its application to the cylinder, the invention has as a further object to provide a novel connection between the cap and the cylinder. I

Another object of this invention is to provide a novel manner of securing the cap in assembled relation with the cylinder and casing for insertion into the support. y f

With the above and other objects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement o-f parts substantially p as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

complete example of the physical embodiment of the invention constructed in accordance with the best mode so far devised for the practical application of the principles thereof, and in which:

Figure 1 is a side view of the front end portion The accompanying drawing illustrates one- (Cl. 'Y0-450) of a lock embodying this invention, having parts broken away and in section;

Figure 2 is a front view of the lock, with parts broken away and in section on the plane of the line 2 2 of Figure 1;

Figure 3 is a bottom View of the cylinder and cap, showing the same properly assembled;

Figure 4 is a perspective view of the cap and cylinder shown separated and ready for assembly; and

Figure 5 is a View partly in section and partly in elevation, illustrating the cap in the act of being applied to the cylinder.

Referring now particularly to the accompanying drawing in which like numerals indicate like parts, the numeral 5 designates the casing of the lock which is adapted to be mounted in a support and which is bored as at 'I to rotatably receive a lock cylinder 8. The support 6 has a chamber S to receive the casing and a hole in its front face into which the front end of the lock cylinder projects to lie substantially flush with the front face of the support.

The cylinder is inserted into the casing bore 'I from its rear end and ymeans (not shown) are provided to hold the cylinder against endwise displacement. The customary tumblers (not shown) are carried by the cylinder to be actuatable by a key insertable into a keway II which opens directly to the outside surface of thevcylinderso that the bottom of the key rests on the bore of the casing.

The extreme front end I2 of the cylinder is reduced in diameter, and a sheet metal cap I3 is telescopedfthereover. The diameter of the front end portion I2 of the cylinder plus the metal thickness of the side wall I4 of the cap is substantially equal to the diameter of the cylinder so as to t the opening I9 in the support, in the same manner as an uncapped cylinder so that the capped construction is interchangeable with cylinders which are directly plated and nished and do not have separate caps.

At a point in line with the shoulder I5 formed by the juncture of the bore or hole I!! with the cavity 9, the side wall of the cap is abruptly enlarged in diameter, as is also the adjacent portion I6 of the cylinder. The extreme inner peripheral edge of the cap is flanged outwardly, as at I'I, which ange is received in a counterbore I8 at the mouth of the bore L` The abrupt enlargement of the cap diameter behind the yshoulder I5 closes the space between the cylindrical surface of the cylinder and the wall of the casing bore to preclude the insertion of thin feelers for the purpose of picking the lock.

Thecap is held in place on the cylinder by a tang i9 forming part of a tumbler retainer 20 iitted to the casing. The tang I9 extends downinto the counterbore, as shown, to overlie the flange` l1.

A keyhole 2l is formed in the front Wall of the cap, which, to permit the key to engage the wall of the bore 1 in the casing, extends through the small diameter forepart of the cap, as best shown in Figures 3 and 4. This keyhole thus substantially splits the cap in two and to guard against bursting stresses incident to the application of the cap onto the front end of the cylinder tearing the cap at the bottom of the keyhole, two tangs 22 are provided in the side wall I4 of the cap, one at each side of the keyhole.V These tangs project inwardly and engage in recesses 23 in the adjacent forepart of the cylinder.

The side walls 24 of these recesses are inclined with respect to true radial planes so that their inner ends at the bottoms of the recesses lie closer to the keyway than their outer ends. The circumferential distance around the front end of the cylinder from edge to edge of the side walls 24 thus increases slightly as this measurement progresses toward the bottoms of the recesses, consequently during the application of the cap to the front end of the cylinder, Vthe cap will be drawn about the cylinder and the tendency to burst the cap will be offset. It is also evident that the interengagernent of the tangs 22 and recesses 23 secures the cap against rotation on the cylinder.

From the foregoing description taken in connection with the accompanying drawing, it will be readily apparent to those skilled in the art, that this invention provides a simple cap structure for cylinder locks, and that it is particularly well suited to the requirements of an installation where the diameter of the forepart of the cap must be kept within that of the cylinder.

What I claim as my invention is:

1. In a lock, a bored casing, a lock cylinder rotatable therein, said cylinder Ybeing inserted through the rear end of the bore and having its front end projecting fromthe casing and having a key slot opening in its cylindrical surface; a cap comprising front and side walls fitted to the front end of the cylinder and having an outside diameter at its forepart substantially equal to the diameter of the cylinder, said cap having a keyhole in its front-wall continuing into the y side wall of its forepart; and means for retaining the cap assembled with the cylinder including interengaging abutments on the cylinder and the side wall of the' cap at opposite sides of its keyhole.

2. In a lock, a bored casing, a lock cylinder rotatable therein, said cylinder being inserted through the rear end of the bore and having its front end projecting from the casing and having a key slot opening in its cylindrical surface;

:.f a cap comprising front and side Walls tted to the front end ofthe cylinder and having an outside'diameter at its forepart substantially equal to the diameter of the cylinder, said cap having a keyhole in its front wall continuing into the side wall of its forepart; and means for retaining the cap assembled with the cylinder including interenga-ging abutments on the cylinder and the side wall of the cap at opposite sides of its keyhole, the abutments on at least one of said parts being tapered so that during application of the cap to the cylinder, the cap is drawn about the cylinder toward the key slot to offset bursting stresses incidental to the application of the cap to the cylinder.

3. In a lock, a lock cylinder having a key slot opening to the cylindrical surface thereof; a cap tted over the iront end of the cylinder, said cap having a front wall provided with a keyhole and a cylindrical side wall telescoped over the forepart of the cylinder,v said side wall of the cap having a forepart equal in outside diameter to the diameter of the cylinder and having the keyhole of the front wall continuing through said forepart of the side wall; and interengaging means on the side wall of the cap and the cylinder at opposite sides of the keyhole to hold the portions of the side wall adjacent to the keyhole against spreading apart during the application of the cap to the cylinder.

4. In combination with a lock cylinder for key controlled tumbler locks having a key slot opening to its cylindrical surface: a cap for the front end of the lock, said cap being formed of sheet metal and having a front wall provided with a keyhole and a multiple diameter cylindrical side wall, the forepart of said side wall having an outside diameter no greater than the diameter of the cylinder and the rear portion of the side wall having a close t on the cylinder, the side wall of said forepart of the cap having the keyhole continuing therethrough; tangs struck inwardly from the side wall of the forepart of the cap at opposite sides of the keyhole; and the adjacent forepart of the cylinder having recesses to receive said tangs; the interengaging portions of the tangs and recesses being so shaped that the cap is drawn about the cylinder during application thereof onto the cylinder.

5. In combination with a lock cylinder for key controlled tumbler locks having a key slot opening to its cylindrical surface: a cap for the front end of the lock, said cap being formed of sheet metal and having a front wall provided with a keyhole and a multiple diameter cylindrical side wall, the forepart of said side wall having an outside diameter no greater than the diameter of the cylinder and the rear portion of the side wall having a close t on the cylinder, the side wall of said forepart of the cap having they keyhole continuing therethrough; tangs struck inwardly from the side wall of the forepart of the cap at opposite sides of the keyhole; and the adjacent forepart of the cylinder having recesses to receive said tangs, said recesses having tapered walls so inclined that during application of the cap onto the cylinder, the consequent engagement of the tangs with said inclined walls draws the cap about the cylinder to offset bursting stresses acting on the cap.

6. In a lock, the combination of: a support having a chamber to receive a lock casing and having a hole in its front wall; a bored lock casing disposed in said chamber; a cylinder rotatable in the bore with its front end projecting into the hole in the support, said hole having a diameter substantially equal'to that of the cylinder, and the forepart of the cylinder which projects into the hole having a smaller diameter; a cap tted over the front end of the cylinder and having a iront wall provided with a substantially diametrical keyhole which continues into the side wall of the forepart of the cap, said cylinder having a key slot in line with the keyhole of the cap and opening to the cylindrical surface of the cylinder, the wall thickness of the orepart of the cap being such that its outside diameter is substantially equal to that of the cylinder; the side wall of the cap having its inner rear part enlarged in diameter to fit the outside of the cylinder and having the juncture of its two diameters engaging the shoulder formed by the innerl end of the hole in the support; and means for maintaining the cap assembled with the cylinder.

7. In a lock: a bored casing having a counterbore at the mouth of its bore; a cylinder rotatable in the bore with its forepart projecting therefrom beyond the counterbore; the extreme forepart of the cylinder being reduced in diameter; a cap fitted over the forepart of the cylinder and having a front wall provided with a keyhole and a cylindrical side wall of two diameters, the smaller of which ts the reduced forepart of the cylinder, said small diameter part of the side wall having the keyhole continuing therethrough, the cylinder having a key slot in line with the keyhole; an annular flange on the inner large diameter end of the cap received in the counterbore of the casing; and means carried by the casing and projecting into the counterbore to overlie said flange.

8. In a lock: a bored casing having a counterbore at the mouth of its bore; a cylinder rotatable in the bore with its forepart projecting therefrom beyond the counterbore; the extreme forepart of the cylinder being reduced in diameter; a cap tted over the forepart of the cylinder and having a front wall provided with a keyhole and a cylindrical side wall of two diameters, the smaller of which ts the reduced forepart of the cylinder, said small diameter part o1 the side wall having the keyhole continuing therethrough, the cylinder having a key slot in line with the keyhole; an annular Iiange on the inn-er large diameter end of the cap received in the counterbore of the casing; means carried by the casing and projecting into the counterbore to overlie said ilange; and cooperating interengageable means on the side wall of the cap and the cylinder for holding the cap against rotation on the cylinder and for offsetting bursting stresses imposed on the cap during application thereof onto the cylinder.

EDWARD N. JACOBI.