US3313134A

US3313134A - Tumbler or locking disks for cylinder locks and a lock provided with such disks

Info

Publication number: US3313134A
Authority: US
Inventors: Gustaf A Gahmberg
Original assignee: Wartsila Oy AB
Current assignee: Wartsila Oy AB
Priority date: 1964-07-09
Filing date: 1965-01-22
Publication date: 1967-04-11
Anticipated expiration: 1984-04-11
Also published as: DE1428562A1; GB1084813A; DK113267B; DE1428562C3; FI43546B; NO115165B; DE1428562B2

Description

April 11, 1967 G. A. GAHMBERG 3,313,134

TUMBLER OR LOCKING DISK-S FOR CYLINDER LOCKS AND A LOCK PROVIDED WITH SUCH DISKS Filed Jan. 22, 1965 FIG. 7

FIG. 4

IN VEN TOR.

United States Patent 4 Claims. 01. 70--376) This invention relates to tumbler disks or so called locking disks in cylinder locks of the type provided with disks for locking function of the cylinder as shown in the Finnish Patent 7,203. In this type of locks a number 'of disks of the shape as shown in FIG. 1 and FIG. 4 are used instead of pins or plungers as for example in Yale or similar locks. The cylinder contains a number of such disks separated from each other by flat and thin disksprings and held within the cylinder by a spring exerting a predetermined pressure ranging from 1 kgr. to 4 kgr. The disks can be rotated in the cylinder a certain angle by the use of the key. The cylinder is open at one end and the cylinder wall has two longitudinal slits reaching from the open end to the bottom. The lug on the periphery of the disk enters into one of the mentioned slits and limits the movements of the disk. In the other slit a so called flocking bar or pin is placed. The locking pin has a length corresponding to the length of the batch of the locking disks. In the wall of cylinder housing is longitudinal groove with a depth of about half of the locking pin, so that when the locking pin rides upon the circumferences of the locking disks half of the body of the pin rests in said groove and the other half remains in the cylinder wall slit, locking the cylinder to its housing.

Each locking disk is provided with a notch in its periphery, differently spaced in each disk of the batch and arranged so that, when the disks are rotated by the action of the key, they can be lined up forming a continuous groove. When this groove, turning the key, comes opposite the slit in the cylinder wall, in which slit the locking pin rests, the pin will be forced out of the cylinder housing groove and into the lined up grooves of the disk batch. The depth of the groove formed by the lined up notches in the locking disks, is about half of the locking pin diameter, thus the disk batch and the cylinder are locked to each other and by further turning of the key the cylinder takes part in the turning movement, which in known way is transmitted to the latch bolt.

This simple design of the locking disks has, however, the disadvantage that it has shown to be possible by introducing through the keyhole in between a disk and the adjacent diskspring a suitably bent thin burglars tool ending with a small hook to feel how the said peripheral notches are located and line them up or choose a suitable skeleton key.

In order to make the locating of the peripheral operative notches on the locking disks more diflicult, the disks were later provided with one or more indentations on one or both sides as disclosed in the Finnish Patent 25,707.

It has been proved that even these notches intended as misguiding indentations in the sides of the locking disks have not been effective enough to prevent the picking of the lock.

In order to obviate this disadvantage, the locking disks according to the present invention have been provided with one or more additional notches arbitrarily spaced along their periphery, these additional notches preferably having the same spacing as the previously mentioned indentations in the sides of the disks. Also, the additional notches may be combined with the indentations, and may have the same peripheral length as the indentations.

One or several or even all of the locking disks in a cylinder may be provided with such indentations and ad ditional notches making the picking of the lock practically impossible or at least extremely difiicult.

The invention will further be described by way of example with reference to the accompanying drawing showing two embodiments of the invention.

FIG. 1 shows a side view of a locking disk with the indentations only on one side,

FIG. 2 shows a part of the circumference of the disk in FIG. 1 as seen in the direction of the arrows I- I,

FIG. 3 shows a part of the circumference of the disk in FIG. 1 as seen in the direction of the arrows II-II,

FIG. 4 shows a side view of a locking disk with the indentations on both sides,

FIG. 5 shows a part of the circumference of the disk in FIG. 4 as seen in the direction of the arrows II I--III,

FIG. 6 shows a part of the circumference of the disk in FIG. 4 as seen in the direction of the arrows IV-IV.

In FIG. 1 each locking disk 1 is provided with an operative notch 2 in its circumference for the locking pin (not shown), an additional fooling notch 3, and, further, with two indentations 4 on the same side of the disk. The spacing of the indentations 4 is arbitrary. As shown in FIG. 1 and FIG. 3, the additional fooling notch 3 may be combined with one of the indentations 4.

FIG. 3 shows a locking disk 1 with the indentations 4 made on both sides. The spacing of these on each side is arbitrary and the indentation 4 can also be combined with the circumferential fooling notches 3 as shown in FIG. 6. The spacing of the indentations 4 can be equal on both sides of the disk and they can thus also be located opposite each other as shown in FIG. 5 and FIG. 6.

The number of circumferential fooling notches 3 as well as the number of the indentations 4 in the side surfaces of the disks is arbitrary as well as their spacing. This makes it exceedingly difficult and tedious or almost imposible for a lock-picker to locate the operative locking pin notches 2 in all the disks in a lock cylinder and bring all the notches 2 in line allowing the locking pin to fall into the groove formed by the lined-up notches 2;; thus allowing the cylinder to be turned in its housing and the latch bolt to be withdrawn and the door opened.

What I claim is:

1. A locking disc for cylinder locks, said disk being provided with an operative notch cut in the circumference thereof and adapted to seat a locking bar; at least one indentation formed in at least one side of the disk in order to make locating of said operative notch difiicult for a lock-picker, said indentation having the same outline as said operative notch and being located similarly, separately, and with an arbitrary spacing along said disk; and means for misleading the lock picker which do not detrimentally interfere with the movement of said locking bar along the circumference of said disk, said means comprising at least one additional notch formed in the circumference of the disk, said additional notch having the same circumferential length as said operative notch and a smaller depth than said operative notch.

2. The locking disk of claim 1, wherein the location of said additional notch wit-h respect to said disk coincides with that of said indentation.

3. A cylinder lock comprising a plurality of coaxial spring loaded disks in juxtaposition, each of said disks being provided with an operative notch cut in the circumference thereof, said operative notches together being adapted to seat a locking bar when aligned; at least one indentation formed in at least one side of each disk in order to make locating of said operative notch diflicult for a lock-picker, said indentation having the same outline as said operative notch and being located similarly, separately, and With an arbitrary spacing along said disk; and means for misleading the lock-picker Which do not detrimentally interfere With the movement of said locking bar along the circumference of said disk, said means comprising at least one additional notch formed in the circumference of each disc, said additional notch having the same circumferential length as said operative notch and a smaller depth than said operative notch.

4. The lock of claim 3, wherein the location of said additional notch with respect to said disk coincides with that of said indentation.

2,301,755 11/1942 Seiffert i 70-376 X 5 2,613,528 10/1952 Salmivuori 70-366 FOREIGN PATENTS 25,707 4/ 1952 Finland.

10 EDWARD c. ALLEN, Primary Examiner.

P. TEITELBAUM, Assistant Examiner.

Claims

1. A LOCKING DISC FOR CYLINDER LOCKS, SAID DISK BEING PROVIDED WITH AN OPERATIVE NOTCH CUT IN THE CIRCUMFERENCE THEREOF AND ADAPTED TO SEAT A LOCKING BAR; AT LEAST ONE INDENTATION FORMED IN AT LEAST ONE SIDE OF THE DISK IN ORDER TO MAKE LOCATING OF SAID OPERATIVE NOTCH DIFFICULT FOR A LOCK-PICKER, SAID INDENTATIONHAVING THE SAME OUTLINE AS SAID OPERATIVE NOTCH AND BEING LOCATED SIMILARLY, SEPARATELY, AND WITH AN ARBITRARY SPACING ALONG SAID DISK; AND MEANS FOR MISLEADING THE LOCK-PICKER WHICH DO NOT DETRIMENTALLY INTERFERE WITH THE MOVEMENT OF SAID LOCKING BAR ALONG THE CIRCUMFERENCE OF SAID DISK, SAID MEANS COMPRISING AT LEAST ONE ADDITIONAL NOTCH FORMED IN THE CIRCUMFERENCE OF THE DISK, SAID ADDITIONAL NOTCH HAVING THE SAME CIRCUMFERENTIAL LENGTH AS SAID OPERATIVE NOTCH AND A SMALLER DEPTH THAN SAID OPERATIVE NOTCH.