CA1250150A

CA1250150A - Arrangement in cylinder locks

Info

Publication number: CA1250150A
Application number: CA000470398A
Authority: CA
Inventors: Bengt O. Sjunnesson
Original assignee: GKN Stenman AB
Current assignee: GKN Stenman AB
Priority date: 1983-12-22
Filing date: 1984-12-18
Publication date: 1989-02-21
Also published as: SE8307139D0; EP0147377A1; FI845020A0; ATE33162T1; DE3470073D1; DK155842C; FI845020L; NO845011L; SE440528B; EP0147377B1; FI77718C; NO165001B; DK625384D0; NO165001C; DK625384A; DK155842B; SE8307139L; FI77718B; US4631941A

Abstract

ABSTRACT

A cylinder lock (1) has a normal locking mode (12 o'clock position) and a service locking mode (10 o'clock position). When the cylinder plug (3) is left in the service mode of the lock, with the aid of standard key, the lock can be turned with the aid of a service key (9).
The service key is latched against withdrawal in the normal mode of the lock, by means of an intermediate pin (7') of larger diameter than a corresponding upper pin (4) in the normal mode of the lock. The intermediate pin can be received in a widened part (3b') of a corresponding pin -channel (3a') in the cylinder plug, but is unable to enter the pin-channel (2a) of the cylinder housing of smaller diameter, hence latching the service key (9). Subsequent to using the service key (9), the cylinder is returned to the normal locking mode (12 o'clock position) with the aid of the standard key, whereafter the lock can only be opened with the aid of the standard key. Each of the two modes can be defined by a spring-biased ball disposed in a suitable pin-channel and arranged to snap-in a corres-ponding empty pin-channel in the plug.

(Figures 3 and 6)

Description

~n a~-rangement in cylinder locks Field of Invention The presen-t invention relates to cylinder locks cf the kind comprising a plug which is mounted for rotation in a plug housing and has a keyway therein for receiving a key, a first row of pin-channels having pins disposed therein and being arranged to co-act with at least two further rows of pin-channels provided in the cylinder housing and having spring-loaded pins disposed therein, of which two further channel-rows one corresponds to a normal lock position in which a standard key can be inserted into the keyway and the plug turned, and a second channel-row is positioned at an angle to the first, this angled posi-tion corresponding to a service position in which a service key can be inserted in the keyway and the plug turned, the arrangement being such that while the standard key can be inserted into the keyway with the pin-channels in the service position, the service key is latched against withdrawal in a normal lock position.
Such locks have the advantage that a person with access to a service key, for example a janitor or like attendant with respect to a block of flats, can obtain access to an apartment with the aid of the key, but only if the occupier of the apartment so permits. When the occu-pier of an apartment is willing for the janitor or like person to enter the apartment during his/her absence, he/she turns the lock to the service position when leaving the apartment, so that the attendant is able to en-ter with the aid of the service key.
When leaving the -flat, however, the attendant is un-able to turn the plug to the normal lock position, since he/she is unable to remove the key from the lock with the plug in this position.
When the occupier of the apartment leaves the lock in the normal lock position, it is not possible -to enter the apartment with the~aid of the service key. ~lthou~i~ in ~onle cases it is possible to inser-t the service key into the keyway, one or more pins in the passa~e ways or channels will prevent rotation of the lock plug.
The plug can be turned with the standard key, however, irrespective of whether the lock is in its normal position or in its service position.

Background ~rt `1 0 Various lock designs are found which utilize the principles of the aforedescribed arrangement. For example, US-A-1 070 367 (Voight) describes a cylinder lock having an additional functional position for a special key. When the plug occupies this additional functional mode, access can be had to the apartment or room, solely with the aid of this special key. In the preferred embodiment, an upper pin located in a pin-channel in the row of channels in the additional functional mode have an upwardly extending peg, which causes the pin to engage the roof of the plug housing, thereby to prevent the plug from being turned with any key other than the aforesaid special key, when the plug occu-pies said additional functional position.
A lock of this design is unsatisfactory, however, since it is a relatively simple matter to file a substi-tutekey so that the part of the key co-acting with the studded pin is able to move the same in a manner to enable the plug to be turned. Thus, a standard key can readilv ~e converted to the aforesaid special key, and be used to gain entry to the apartment, even when the locJc is turned to the additional functional mode.
NO-A-793 880 (Elkem Spigerverket) describes a similar lpck in which tile number of pin-channels in the normal lock position cliffer frolll the number of pin-chanl1els operative in the additiol1cll ful-ctional mode or service mode thereof, thereby enablincl tlle key to be l,ocked.
slockill~ of the key is effected by e~cludin~ the pLesenCe of eertain pin-channels for u2per pins in one of Lne saicl loek positions, so as to prevent the lower pin or pins from moving upwardly in this position. This lock also has the same disadvantage as the lock previously described, sinee it is a simple matter to modify a standard key to fit the lock and function in the additional or service mode, thereby overriding the design latching effect.
US-A-4 300 374 (Mullich et al) describes a similar loek arrangement, although in this ease the special key has limited manouverability.
US-A-1 922 438 (Hurd) deseribes an arrangement in whieh pin-seetions ean be tipped over in a manner to retain the key.
One disadvantage with the majority of the aforemen-tioned known loek designs is that they can readily beforeed. This applies, for example, to the deseribed Nor-wegian loek design, when one has pre-knowledge of the particular pin-ehannel which does not co-aet with a pin-ehannel in the plug housing. Another disadvantage is that the serviee key ean readily be filed to fit the lock in its normal lock position.

Object of the Invention An object of the invention is to provide a eylinder lock of -the aforesaid kind, with which the dis-advantages inherent Wit}l similar known lock designs are avoided; whicll cannot be readily forced; and which does not provide the possibility of opening the lock with the plug in the normal lock position with the aid of a modi~ied service key.
Another object of the invention is to provide a cylinder lock of simple desicJIl and low cost with respect to necessary ancillary devices which, despite its simplicity, is highly reliable and burcJlar-safe.

Brief Disclosure of the Invention A lock according to the present invention is characterized in its widest aspect substantially in that one or more of the pin-channels of the cylinder housing in said second row, corresponding to the service mode of the lock, accommodate intermediate pins in addition to said upper pins;
that one such intermediate pin has a larger diameter ~an the bore of the coxresponding pin-channel of the first row of pin-channels, and in that corresponding pin-channels in the cylinder plug have a widened part capable of accommodating said intermediate pin of larger diameter.
Among other things, the invention affords the advantage that the service key is effectively latched in the normal lock position, without it being possible to know beforehand which of the pin-channels accommodates the intermediate pin effecting the latching action. This makes it more difficult to file the service key to a form in which it is not latched in the normal lock position.
A further ~dvantage is that it is comparatively simple to provide a pin-channel of larger diameter than remaining channels, and to provide the cylinder plug with a flared or widened portion capable of receiving an intermediate pin of said larger diameter.
Thus, with a lock of this design, when attempting to withdraw the service key in the normal lock position the intermediate pin will strike against the overlying narrower pin-channel in the plug housing, i.e. without being able to move upwardly therein, thereby effectively latching the key against withdrawal.
Several of the pin-channels in said second row, i.e. corresponding to the service position, can be pro-vided with intermediate pins which render forcing of thelock difficult. The position of the pin-~el of larger 5 ~ 5~

diame+:er may also be varied, -thereby makiny -the task of forcing the lock even more difficult.
In the normal lock position, the coinciding pin-channels in the cylinder housing and plug respectively solely accommodate upper and lower pins respectively, i.e.
the intermediate pins are omitted in this case. The form and design of these pins, however, can be varied in a conventional manner. For example, both the upper and lower pins may comprise various types of safety pin, pins having hardened cores, and so-called pear-shaped pins.
In practice it is preferred that the in-termediate-pin accommodating pin-channel of larger diameter in the plug housing also accommodates an upper pin of the same diameter as the intermediate pin.
The service position can be defined by a spring-biased ball disposed in a suitable pin-channel in said second row and arranged to snap-into a co-acting pin-channel in the plug, said co-acting channel preferably being an empty channel.

2~ The normal lock position can also be defined in a corresponding manner.
~n embodiment of the invention will now be described in more detail with reference to the accompanying drawings.

Brief Description of the Drawings Figure 1 is a sectional view through a cylinder lock provided with an arrangement according to the invention, and illustrates the cylinder plug in its normal lock position.
Figure 2 is a sectional view -tak.en on the line in Figure 1.
Figure 3 is a view corresponding to the view of Figure 2, but with the cylinder plug in its service mode.
Figure 4 is a sectional view taken on the line IV-IV
in Figure 2.
Figure 5 is a sectional view through the cylinder lock, corresponding to the view of Figure 1, with a standard key inserted.
Figure 6 is a sectional view corresponding to the view of Figure 5, in which the service key has been in-serted into the service position and turned to -the normal lock position, whereupon the service key is held latched against withdrawal.
Figure 7 illustrates in larger scale a part of Figure 6, namely the intermediate pin of larger diame-ter operative in latching the service key.
Figure 8 illustra-tes the position in which the service key has been inserted into the lock in its normal lock position, whereupon rotation of the cylinder plug is prevented.
Figure 9 is a partially cut-away view of a modified embodiment, corresponding to the view in Eigure ~.
Figure 10 is an immediate side view of the embodi-ment illustrated in Figure 9, with the cylinder plug in the service mode of the lock.

A Preferred Embodiment of the Invention Referring first to Figures 1-4 there is illustrated a cylinder lock 1 having a cylinder housing 2 which has a cylinder plug 3 disposed for rotation therein. The cylinder housing is provided with two rows of pin-channels, namely one row of pin-channels corresponding to the normal locking mode of the cylinder plug (the 12 o'clock posi-tion). These pin-channels are referenced 2a and, as illustrated in Fig.1, accommodate upper pins 4 biased by springs 10, said upper pins being of mutually different configuration and having mutually different characteristics. Thus, some of these pins are provided with hardened cores, to render drilling of the cores difficult.
In a corresponding manner the cylinder plug 3 is provided with a row of pin-channels 3a accommodatinq lowex pins 5, which similar to the upper pins have mutually different configurations and characteristics.

The keyway of the cylinder plug is referenced 3c.
The housing 2 is also provided with a second row of pin-channels, here re~erenced 2b. A plane extending through the first row of pin-channels is able to form an angle, for example, of 40 with a plane passing through the second row of pin-channels. In other words, the row of pin-channels in the core, with the channels in the 12 o'clock position, coincide with the first row of pin-channels in the cylinder housing, while when the plug-channels occupy the 10 o'clock position they coincide with thesecond rcw of channels, corresponding to the service mode of the cylinder plug.
As illustrated in Fig. 4, some of the pin~nnels 2b accommodate both upper pins 6 and intermediate pins 7. One of the pin-channels, namely the fifth ~nel from the mouth of the keyway 3c, has a laroer diameter than rem~ing pin-channels.
This pin-channel is referenced 2b'. me pin-channel acol~dates an upper pin 6' and an intermediate pin 7'. The diameter of the upper pin 6' and the intermediate pin 7' may be as lar~e as

3.5 mm,while the rem~n~ pins have a diameter of about 3 mm.
As illustrated in Figs. 6 and 7, corresponding channels 3a' in the cylinder plug have a widened portion 3b' at their upper end, i.e. the end located adjacent the periphery of the cylinder plug, the depth of said widened portion being such as to enable it to accommodate the intermediate pin 7'. It will be seen frc~ Fig. 7 that in this position the intermediate pin 7' is prevented from mcving up-wardly by the step between the widened portion 3b' and the bore 2a for the upper pin 4 in the overlying pin-channel 2a. mus, a service key 9 which has been inserted into the cylinder plug in the service mode illustrated in Fig. 3, (the 10 o'clock position), and the plug subsequently turned to the normal lock position (the 12 o'clock position), cannot be withdrawn from the cylinder lock, since such with-drawal is prevented by the intermediate pin 7'.
Figure 5 illustrates the situation when an apartmentkey 8 is inserted into the cylinder plug in the normal 8 f~

lock mode and then turned ln the normal manner. In -this case, the dividing llne or pitch line between -the upper pins 4 and the lower pins 5 coincides with the periphery of the cylinder plug.
When the apartment key 8 is now removed from the cylinder plug in the service mode illustra-ted in Fig. 3, the upper pin 6' and the intermediate pin 7' adop-t the position illustrated in said Figure. The service key 9 can be inserted and the plug rotated. In the normal mode of the lock, however, the situation is that described with reference to Figures 6 and 7, i.e. the service key 9 is latched against withdrawal.
Fig. 8 illustrates that al-thouyh the service key 9 can be inserted into -the cylinder plug with the lock in its normal mode, rotation of the plug is prevented by the upper pin 4. The service key 9 can be readily withdrawn, however.
Figures 9 and 10 illustrate a modified embodimen-t.
In this modified embodimen-t, when seen from the mouth of the keyway 3c the terminal pin-channel 2b" and 2a" of respective rows of pin-channels, both in the service mode and the normal mode of the lock, lack a pin and are instead provided wi-th a ball 11 whose diameter is sligh-tly smaller than the diameter of the respective pin-channel, so that the ball 11 is able to move readily in the channel, against the action of a spring 10.
A corresponding pin-channel 3a" in the cylinder plug, this pin-channel in the embodiment illustrated in Figs.
1-8 accommodating a lower pin 5, is empty in the embodiment of Figs. 9 and 10, thereby enabling the ball 11, when -the plug 3 is -turned to respective positions by means of the key, to accurately define said position with a snap-in action, and loosely retain the cylinder in this position.
In other words, it is not necessary to seek the normal or service mode of the lock, but that the ball 11 snaps-in immediately and accurately defines the position of the cylinder, so that, for example in the service posi-tion of the lock, the apartmen-t key 8 can be readily removed and the service key 9 readily inserted.
The service key 9 may be a master key whLch fits, for example, all apartments in an apar-tment building or a living area, or alternatively all apartments on one floor of an apartmen-t block. The s-tandard key 8, on the other hand, is preferably not of this kind, i.e. each standard key fits the lock of only one apartment or dwelling house.
Thus, in such cases one or more of -the pin-channels in the service mode of the lock will accommodate intermediate pins, while the pin -channels in the normal mode of the lock will lack such intermediate pins.

Claims

Claims:

1. A cylinder lock having a cylinder plug which is rotatably disposed in a cylinder housing and has arranged therein a keyway and a row of pins accommodated in pin-channels for co-action with at least two rows of pin-channels disposed in the cylinder housing and having arranged therein spring-biased pins, namely a first row of pin-channels corresponding to a normal mode of the lock, in which a standard key can be inserted to turn the plug, and a second row of pin-channels disposed at an angle to the first row and corresponding to a service mode, in which a service key can be inserted to turn the cylinder plug, wherewith the standard key can also be inserted to and removed from the cylinder plug in the service mode of the lock, while the service key is latched against withdrawal in the normal mode of said lock, characterized in that one or more of the pin-channels of the cylinder housing in said second row, corresponding to the service mode of the lock, accommodate intermediate pins in addition to said upper pins;
that one such intermediate pin has a larger diameter than the bore of the corresponding pin-channel of the first row of pin-channels, and in that corresponding pin-channels in the cylinder plug have a widened part capable of accommodating said inter-mediate pin of larger diameter.

2. A cylinder lock according to claim 1, characterized in that the pin-channels in the first row of channels accommodate upper pins of mutually different configuration and mutually varying characteristics.

3. A cylinder lock according to claim 1, characterized in that only pin-channels associated with the second row of pin-channels in the cylinder housing accommodate intermediate pins.

4. A cylinder lock according to any one of claims 1-3, characterized in that a pin-channel in the cylinder housing accommodates a ball which is biased by a spring and which is arranged to snap-into a corresponding pin-channel in the cylinder plug, said channel preferably being empty, i.e.
has no lower pin arranged therein.

5. A cylinder lock system, comprising: a cylinder plug rotatably disposed in a cylinder housing and having arranged therein a keyway and a row of pins individually accommodated in a plurality of pin-channels for co-action with first and second rows of pin-channels defined in the cylinder housing and having individually arranged therein a plurality of spring-biased pins, said first row of pin-channels corresponding to a normal mode position of the lock, and said second row of pin-channels being disposed at an angle to the first row and corresponding to a service mode position of the lock, a standard key insertable into the keyway, and a service key insertable into the keyway, wherein one of the pin-channels in said second row accommodates an intermediate pin and an upper pin, said intermediate pin having a larger diameter than upper pins in the first row of pin-channels, a corresponding pin-channel in the cylinder plug has a widened part at a radially outer end thereof for fully receiving said larger diameter intermediate pin, said standard key is operable to rotate the cylinder plug in both the normal and service mode positions, said service key is operable to rotate the cylinder plug only in the service mode position, and the larger diameter of the intermediate pin blocks the entry thereof into a narrower first row pin-channel when the cylinder plug is rotated to the normal mode position by the service key to thereby latch the service key against withdrawal.

6. A lock system according to claim 5, wherein the pin-channels in the first row of channels accommodate upper pins having different body configurations.

7. A lock system according to claim 5, wherein only pin-channels in the second row accommodate intermediate pins.

8. A lock system according to claim 5, wherein a pin-channel in the cylinder housing accommodates a ball biased by a spring and arranged to snap into a mating pin-channel in the cylinder plug, said mating pin-channel having no lower pin disposed therein.