GB2138483A - Door lock - Google Patents

Abstract

A door lock comprises a housing (1), a dead bolt (4) and at least on a first side of the housing, a first type of connection member (10) connectable to a turnable knob or the like. The first type of connection member (10) is also operatively connected to the dead bolt (4) for manual operation thereof between a protruding locking position (not shown) and a retracted releasing position. At least on the opposite side of the housing (1), there is a second type of connection member (8) connectable to a key-operated lock unit. The second type of connection member (8) is also operatively connected to the dead bolt (4). The operative connection (26,27,17,21) between the first type of connection member (10) and the dead bolt (4) includes means (26) for temporary disconnection of this connection for excluding manual operation of the dead bolt (4) and thereby make the door lock temporarily operable only from a key-operated lock unit coupled to the second type of connection member (8). <IMAGE>

Description

SPECIFICATION Door lock The invention relates to a door lock comprising a housing, a dead bolt slidably mounted within the housing for movement between a protruding locking position and a retracted releasing position, a dead bolt moving mechanism located within the housing for moving the dead bolt between said positions, and first andsecond types of connection memberturnably mounted in the housing and each operatively con nectedtothe moving mechanism, thefirsttype of connection member being accessible from at least one side ofthe housing and the second type of connection member being accessible from at least the othersideofthe housing.

Thefunctions of a normal door lock usually require that the lock includes a latch bolt. This is also the case in a door lock according to the invention. However, the latch bolt per se forms no part of the present invention, since itfunctions in a conventional manner. For moving the latch bolt, a handle, a turnable door knob, orsomesimilarlock-operating device, is normally needed although ifthe latch bolt is a roller bolt ora latch member of similartype, no lock-operating device is needed, sincethe latch bolt then functions automatically, when the door is shut or opened by pushing or pulling.

Many attempts have been made to obtain a series of locks, in which thesame lock housing may be used in different locktypes having different functional characteristics, see for instance published Finnish Patent Application 763696, and G B-A-2097462. Since the desired functions of door locks for different purposes are partly mutually exclusive, it is difficult to find a perfect solution.

Embodiments of the present invention are capable of providing a door lock which can be used for obtaining at least the following lockfunctions.

Firstly, a normal front door lockfunction, which means that the lock may be operated manually from one side (the inside) ofthe door but only by means of a keyfromthe other side (the outside).

Secondly, a dead locking front door lockfunction, which means that it is not possible to operate the lock manually from the inside of the door.

Thirdly, a purely key-operated function only allow ing opening ofthe door by means of a key inserted into the doorfrom either side.

Fourthly, a manual emergency opening function, which means that a normally key-operated locked door may be manually opened from one side in an emergency situation.

What constitutes a door lock in accordance with the invention can be taken from the following claim 1, and using a door lock constructed in accordance with the invention each of the functions mentioned above can be provided by appropriate use well known tock-operating devices, such as, for example, tu rnable door knobs and key-operated cylinder lock units.

If it is required that a key-operated lock unit is connectable to both sides ofthe door lock, the door lock is provided with a second type of connection member accessible from each side ofthe housing, each connectable to a key-operated lock unit, both second type connection members being independently operatively connected to the dead bolt moving mechanism ofthe door lock.

Afront door lock dead locking function may be obtained by providing the door lockwith its firsttype of connection memberfor a turnable knob and with its second type of connection memberfora key-operated lock unit. Both types of connection memberare operatively connected to the dead bolt moving mechanism in such a way, that byfirstturning the turnable knob into a security position outside its normal operating sector, whilethe dead bolt is in its retracted releasing position, and by moving thereafter the dead boltto its protruding locking position, by means ofthe second type of connection member, disconnection of the operative connection between the firsttype of connection member and the dead bolt moving mechanism can be accomplished.Thereby the dead boltcannot be moved backto its retracted releasing position byturning the knob.

In a preferred embodiment ofthe invention, a fork-and-pin-mechanism is used in the operative connection between the knob and the dead bolt moving mechanism. Such a fork-and-pin-mechanism can be so arranged, that by turning the knob into the said security position, the fork member of the fork-and-pin-mechanism moves away from its en gagement with the pin, which in the next phase, when the dead bolt is moved to its protruding locking position by means of a key-operated lock unit, moves to such a position in relation to the fork member, that the fork member cannot be operatively connected thereto.Suitably, the fork member is operated by the knob and the pin is attached to an operating member forming a part of the dead bolt moving mechanism, which operating member may be operated from a key-operated lock unit as well as from the knob via the fork-and-pin-mechanism. This operating member is preferably a turnable member, but it is also feasible for itto be a suitably guided sliding member.

Preferably, theturnable knob ofthe just-described door lock should be prevented from inadvertently moving into its security position and this preferable feature can be obtained by ensuring a suitable spring load normally acts to preventthe inadvertent move ment ofthe knob. Fortemporarily retaining the turnable knob in its security position a stop member can be used, which retains theturnable knob in the security position in spite ofthe aforementioned spring load. The stop member may be spring-loaded and can operate automatically or in a manuallysettable manner. For example actuation of the knob may require a pushing of a push knob or the like arranged in the turnable knob. The function ofthe lock releases the stop member, and hence, alsotheturnable knob.

In orderto obtain high functional reliability, the door lock is conveniently provided with an automatic reset ofthe temporarily disconnected operative connection. Thus in the case of a fork-and-pin-mechanism, the fork member may again receive the pin, when the dead bolt moves back to its retracted releasing position. This resetfeature is easily achieved by arranging, on a rear portion ofthe dead bolt, an abutment for pulling the fork member back into its operative position when the dead bolt moves to its protruding locking position. Then the fork member automaticallyengagesthe pin, when the dead bolt again moves backto its retracted releasing position.

Functional security can further be improved by providing the door lock with a relatively weak spring member arranged to retain the fork member in a position where it receives its pin. This spring member mayfunction also as a means to keep the turnable knob in its normal position.

When it is desired to use a door lock according to the invention as a purely key-operated lock, the housing can be mortised in the door, in such a waythat a portion of the door covers the otherwise accessible firsttype of connection member of the door lock.

When it is desired to provide a function, such that a locked door, in the event of an emergency, can be manually opened without a keyfrom-one side ofthe door, a turnable knob connected to the firsttype of connection member can be installed atthat side ofthe housing. Since the turnable knob is to be used only in an emergency, it can be covered by a protective cover (e.g. a breakable plastics cover) or it can be locked by means of a breakable seal orthe like. Ifthe door is to be opened manually, the cover or seal can then be broken.

Embodimentsofdoorlockin accordancewiththe invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is an exploded view of one embodiment of a door lock provided with a turnable knob, Figure 2 is a side view ofthe upper portion of an opened lock housing of a second embodiment of door lock, Figure 3 is a schematic representation ofthe spring load system oftheturnable knob of the door lock shown in Figure 1, and Figure 4 is a schematic representation of the function of the stop member of theturnable knob of Figure 3.

In Figures 1 and 2, the numeral 1 indicates the housing of a door lock, 2 its fore-end, 3 a latch bolt and 4 a dead bolt. The latch bolt3 is movable by means of a follower 5,to which a handle 6 is connected. The dead bolt 4 can be moved via a connection member 8 by a key-operated lock unit 7 and via a connection member 10 by a turnable knob 9. The rectangular openings in thefollower 5 and in the connection member 10 extend through the housing 1 so that lock-operating devices can drivablyconnectwiththese openings on either side of the housing 1. A connection member 8 is evident on each side of the housing 1 butthese function independently of each other, which means that the connection member 8 on eitherside can be turned without influencing the connection member8 on the opposite side.The key-operated lock unit 7 shown in Figure 1 contains a conventional cylinder lock mechanism.

Theturnable knob 9 isjournalled in an attachment plate 11, which its firmly pressed against a surface of the door by a shield ring 12 of the cylinder lock unit 7.

The attachment plate 11 includes an opening, the shape and size of which at least partly correspond to the shape and size of the cylinder lock unit 7,so that the position ofthe plate 11 on the door is set by side surfaces ofthecylinderlockunit7. Forconnectingthe turnable knob 9 to its connection member 10 a flat shaft 13 is used. An opening has to be bored in the doorfortheshaft 13.

If the door lock is to be used withoutaturnable knob 9 on either side ofthe door, no opening forthe shaft 13- is bored in the door on that side and theturnable knob and its attachment plate 11 are not required as door furniture on that side.

The cylinder lock unit7 shown in Figure 1 is attached directly to the housing 1 by means of a pair of screws 15 threaded into the housing 1, although of course one screw 15 could be used in place ofthetwo. Cylinder lock units 7 are preferably used on both sides ofthe door, and the screw(s) 15 extending from one side through one cylinder lock unit can pass completely through the housing 1 and bethreaded in the opposite cylinder lock unit or provided with (a) nut(s) so that the cylinder lock units are securely clamped to opposite sides ofthe housing 1.The position oftheor each cylinder lock unit is determined by the respective connection member8and,inaddition,theattachment ofthe or each cylinder lock unit is augmented by an associated shield ring 12, the attachment screws 14 of which can extend through the housing 1 to be threaded into the inner side of a corresponding shield ring on the opposite side ofthe door.

Figure 2 shows those members of the door lock which are usedfor moving the dead bolt 4. The connection member 8 of each key-operated lock unit includes a pin 16, either of which can transmitturning force to a recess 24 of a turnable member 17 which is capable of operating the dead bolt 4. The turnable member 17thus forms part of the dead bolt moving mechanism and isiournalled on a pivot 18. A stationary plate 19, supported within the housing 1 by pins 28 is located between the two coaxial connection members 8. This plate 19 ensuresthatwhere cylinder lock units 7 are provided on each side ofthe door they will function independently of each other.

The movement of the dead bolt 4 is guided byan opening inthefore-end 2 ofthe housing 1 and buy a stationary pin 20 in the housing. The turnable member 17 transmits force to the dead bolt 4 by means of a lever 21, rigid with the member 17, the outer end ofwhich lever is locatable in a force transmission recess 22 ofthe dead bolt. In Figure 2, theturnable member 17 and the lever 21 are shown in their dead locking position, in which a stop surface 23 ofthe lever 21 prevents the dead bolt4(in its protruding locking position) from moving to the right.

In the retracted releasing position ofthe dead bolt 4, the stop surface 23 has a corresponding effect on the dead bolt but now prevents itfrom moving to the left.

The dead bolt4can also be moved by means of the, knob connection member 10.This member is connected to a fork 26, which normally is inforce transmitting engagementwith a pin 27 on the turnable member 17. When the dead bolt4isinits retracted releasing position, it is possibletotum the fork member 26to the rightinto a position26a, whereby it is released from its engagement with the pin 27. This position is obtained byturning the turnable knob 9 to its security position. When the fork 26 is in the position 26a, the dead bolt 4 can be moved outwards into its protruding locking position by means of either ofthe key-operated lock units 7.

Thereby, an abutment 25, atthe inner end ofthe dead bolt4 movesthefork 26 back to a substantially vertical position, buttheturnable member 17 and its pin 27 have now moved to such a position, thatthe pin 27 is outside the fork26 and is not engageable thereby. This means that the dead bolt 4 cannot be retracted byturning the knob 9. The movement of the dead bolt back into its retracted releasing position can only be performed by key operation of one of the cylinder lock units 7. Retracting the dead bolt by key operation, brings the fork 26 and the pin 27 again into engagement. When the fork 26 is brought back into its substantiallyvertical position by the abutment 25, the turnable knob is also brought back to its normal position.The knob connection member 10 and the turnable member 17 are also interconnected by a spring 29, the main function of which isto keep the turnable member 17 in either one of its extreme positions, so thatthe stop surface 23 ofthe lever 21 is in a position which immobilisesthedead bolt4.

Figure 3 shows one construction fortheturnable knob 9. Rigid with the knob 9 there is a member 30, which, when the knob 9 is turned clockwise, compresses a spring 32 located in a bearing housing 31 of the knob. The opposite end ofthe spring 32 is supported by a stationary support member 33. When operating the dead bolt4,theturnableknob9moves within its normal operating sector a, without being subjectto any spring load. A stationary protrusion 34 and the support member 33 prevent the spring 32 from acting when the knob 9 is moving within the sector a.

When the turnable knob is turned into its security position, a clockwise movement through an angle b against the load ofthe spring 32 is required. The turnable knob is locked in its security position by means of a push knob 35 provided therein, the function ofwhich is illustrated in Figure 4. The turnable knob shown in Figure 3 is intendedfora door, having its hinges on the right side when viewed from the side oftheturnable knob. Hence, it is natural, thatthe knob 9 is turned counter-clockwise, when the dead bolt is to be moved to its protruding locking position. lithe hinges ofthe door are on the left side of the door, it is natural to turn the knob 9 clockwise, when the dead bolt isto be moved to its protruding locking position.For making it possible to use the sameturnable knob in both cases, the su pport member 33 is made detachable and an installation recess (not shown) is provided for itwhich is symmetrically located on the other side ofthe stationary protrusion 34. By inserting the support member33 intothis second position and byrepositioning the spring 32 into a corresponding operative position, an arrangement is obtained, which is a mirror image ofthesituation shown in Figure 3.

in Figure4,the function ofthe stop member of the turnable knob 9 is illustrated. The push knob 35 of the knob 9 pushes, in the security position ofthe knob, a stop pin 36 inwards, so that the inner end thereof enters into a stationary recess 37. The stop pin 36 has asmall retainer ball 39,which keepsthe pin 36 flexibly in each of its end positions. The recess 37 has oblique side surfaces and the head 38 ofthe pin 36 has corresponding oblique surfaces. This means that a sufficiently powerful turning moment acting on the turnable knob 9 releases the stopfunction of the pin 36 byforcing the pin outwards. The pin 36 may be made of a low friction plastics material. In order that the knob could be used with either left-hand hinged or right-hand hinged doors, two holding recesses 37 should be provided symmetrically with respect to the protrusion 34.

When a door lock according to the invention is required to provide an emergency opening function, this is obtained simply by installing, at one side ofthe door, a turnable knob, which is enclosed in a (preferably transparent plastics) protective cover 40.

The cover 40 is breakable or removable in an emergency situation to expose the tu rnable knob.

Normally, the turnable knob is not used, because of the protective cover 40.

The invention is not limited to the embodiments described with reference to the drawings, since several modifications thereof are feasible within the scope of the following claims.

Claims (14)

1. A door lock comprising a housing, a dead bolt slidably mounted within the housing for movement between a protruding locking position and a retracted releasing position, a dead bolt moving mechanism located within the housing for moving the dead bolt between said positions, and first and second types of connection memberturnably mounted in the housing and each operatively connected to the moving mechanism, the firsttype of connection member being accessible from at least one side of the housing and the second type of connection member being accessible from at least the other side of the housing, characterised in that the operative connection between said firsttype of connection member and said dead bolt moving mechanism includes meansfor temporary disconnection of said operative connection.

2. A door lock according to claim 1, in which on both sidesofthe housing a second type of connection member is accessible but each second type of connection member is operatively connected to the dead bolt moving mechanism independently of the other second type of connection member.

3. A door lock according to claim 1 or 2, in which the first and second types of connection member are so operatively connected to the dead bolt moving mechanism, that byfirstturning a turnable knob connected to a first type of connection member into a security position outside its normal operating sector, while the dead bolt is in its retracted releasing position, and by moving thereafterthe dead bolt into its protruding locking position by operating the second type of connection member, a disconnection of the operational connection between the firsttype of connection member and the dead bolt moving mechanism is obtained, which excludes any moving ofthe dead bolt back into its retracted releasing position by operating the first type of connection member.

4. A door lock according to claim 3, in which the operational connection between the firsttype of c Jnnection member and the dead bolt moving mechanism includes a fork-and-pin-mechanism so arranged, that byturning aturnable knob connected to a firsttype of connection member into its security position, the fork member of the fork-and-pin mechanism is disengaged from the pin thereof, and that, when the dead bolt moving mechanism, operated via a second type of connection member, moves to its protruding locking position, the pin is brought out of reach of the fork member, thereby preventing thefork memberfrom operatively engaging the pin while the dead bolt remains in its protruding locking position.

5. A door lock according to claim 4, in which the fork member is rigid with a first type of connection member and the pin is rigid with a memberforming partofthe dead bolt moving mechanism, said last mentioned member being operatively connected to the firsttype of connection member(s) as well as to the secondtype connection member(s).

6. Adoorlockaccordingto any of claims 3-5, in whichtheturnable knob has yielding stop means capable of keeping theturnable knob in its security position.

7. A door lock according to any of claims 3-6, in which a spring member is arranged to influence said turnable knob when it moves to its security position outside its normal operating sector.

8. A door lock according to claim 4 or any claim dependent thereon, in which there are automatic reset means bringing the fork member of the fork-and-pin-mechanism back from its disengage ment position to a ready position, in which it is able to receive the pin of the said mechanism, when the dead bolt moves back to its retracted releasing position.

9. A door lock according to claim 8, in which a spring flexibly retainsthe fork member in its ready position.

10. A door lock according to claim 9, in which the spring also functions as aflexible retainerforthefirst type of connection member.

11. A mortised installation of a door lock according to claim 1 or 2, in which thefirsttype of connection member is concealed behind a covering portion of a door in which the door lock is installed.

12. Adoorlockaccording to anyofthe preceding claims, in which a seal member is arranged to prevent use of a turnable knob connected to the first type of connection member, said seal member being break able for emergency use of said tu rnable knob.

13. A door lockaccording to any of the preceding claims, in which a manually operable latch bolt is provided in the housing in addition to the dead bolt.

14. A door lock substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.