GB2272247A

GB2272247A - Axial push and pull locking device

Info

Publication number: GB2272247A
Application number: GB9223175A
Authority: GB
Inventors: Gary Christian
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-11-05
Filing date: 1992-11-05
Publication date: 1994-05-11
Also published as: GB9223175D0

Abstract

An axial push and pull locking device has a housing 1 incorporating a conventional cylinder type lock 2 which transmits the rotary motion of its spindle 3 when the security key is turned. A driving means 4 attached to the lock spindle engages one or more helical grooves within the drive bush 5 which is restrained rotationally via a key 6 in a keyway 7 within the housing and causes the drive bush to convert the rotational spindle effort and be driven axially along the keyway. The drive bush is fitted with a variety of end fittings to effect numerous linear latching, catching or switching operations which are then able to be locked out at either extreme of travel or at any intermediate position depending upon the type of lock barrel employed. <IMAGE>

Description

AXIAL PUSH AND PULL LOCKING DEVICE This invention relates to a locking device whereby the rotary action of a conventional cylinder lock is converted to an axial push and pull action.

Cylinder locks as generally used in the security and safety field comprise of an anangement of pins or tumblers housed within a cylindrical barrel. Insertion of the correct key allows the pins or discs to adopt a status such that the rotary action of turning the key allows direct rotary motion of thc lock spindle, directly proportional to the movement of the key itself.

The lock spindles can be fitted with a vast array of cams and levers which cause entrapment within the associated latching equipment which rely upon rotary action to perform thier intended locking functions.

In such instances where it is desireable to perform an axial push or pull operation the lock cylinder or basel must be manually pushed or pulled along its axis by the key operator - A spring return mechanism is sometimes provided in such instances.

According to the present invention there is provided an axial push and pull locking device for the incorporation of conventional cylinder locks whereby the assembly is constructed so as to convert the rotary action of the existing lock spindle into a linear and axial movement (push and pull) of an integral drive: bush and so designed that the length of linear travel is proportional to tile a:igulz dcgruc ol rolalioll of thc lock spindle and that the drive bush is able to accommodate various cnd fittings which allow the linear motion to be transferred to various actuating apparatus.

Specific embodiments of the invention will now be described by way of examples with reference to the accompanying drawings in which : Figure 1 shows the general layout of the mechanism.

figure 2 illustrates the adoption of the mechanism to provide mechanical seperation and engagement of electrical contacts for circuit isolation purposes.

Figure 3 illustrates the adoption of the mechanism to provide mechanical extension and withdrawal of a bolt Figure 4 illustrates the adoption of the mechanism to provide the extension and retraction of a hydraulic or pneumatic piston.

Referring to the drawings the device compriscs a housing reccptacle 1 incorporating a cylindrical bore of sufficient diamctcr to accommodate the proprictary lock cylinder 2.

The lock cylinder featurcs an extended spindle 3 the end of which compriscs the axial push and pull apparatus, in this particular instance a simple drive pin 4 is illustrated. The drive mechanism engages within a helical groove within the drive bush 5 the pitch of which determines the amount of linear travel in relation to the degree of rotary motion enacted by the lock spindle. The drive bush is prevented from rotating via a key 6 engaging in keyway 7 within the housing receptacle.

The efficiency and power transmitted by the drive bush may be improved by additional helical grooves within the drive bush, ie, the number of wstartsr . An adaptor 8 couples the motion of the drive bush to the required cxternal or integral applicator mcdium. which subsequently interacts with the intended calollment, latching or clcctrical switching equipmcnL In order to activate the mechanism the relevant key is inserted within the lock cylinder and is rotated in the conventional manner.As shown in figure 1, the rotary motion enacted upon the key causes the lock spindle 3 to rotate thereby imparting a rotational movement to the drive pin 4, which subsequently attempts to impart rotational movement to the drive bush S which is prevented from rotating by its Ey 6 which is engaged with kcyway 7 formed in the housing receptacle 1.

As the drive bush is free to travel axially within the keyway, the imparted rotary forces acting upon the drive pin causes the drive bush to be driven via the helical grooves in a linear direction within the housing receptacle. Revcrse rotation of the lock spindle will cause the drive bush to be driven in the opposite dircction In operation various devices may be attached to the drive bush and in doing so will be provided with a lockable facility, in a retracted, cxtended or any intermediate position along the axis of the lock spindle, making the device suited to a variety of security or safety applications.

Referring to figure 2 by way of example only illustrates the device as a mechanically operated electrical isolation device whereby axial movement of the drive bush, effected by turning the key causes mechanical seperation of the electrical contacts 9 from their mating cable conections 10.The example further illustrates that the contacts 9 could be housed internally and codcd in such a manner as to prevent external visible identification of the circuit layouL Such a device could be uscd as a vehicle anLi-lheít immobiliser, isolating various major electrical circuits within the vehicle that would prevent nn Imauthorised person from driving the vehicle away under its own power.

Referring to figure 3 by way of cxample only illustrates the device as a mechanical and direct acting security bolt whereby axial movement of the drive bush effected by turning the key causes a hardened steel bolt 11 say to engage with the latching component as could be fitted to an opening or sliding door.

Rcferring to figure 4 by way of example only illustrates the device as a mechanically operated means to remotely activate cithcr a hydraulic or a pnucmatic cylinder, cither directly or by way of a slave cylinder. Lincar movemnt of the drive bnsll effected by turning the key causes pislon 12 to transmit movcmcnl by air or fluid power to tlic remotely located cylinderislave cylinder which subsequently transmits tile movement to activate say a locking bolt similarly in the manncr as described for figure 3.

Claims

1. An axial push and pull locking device for the incorporation of conventional cylinder locks whereby the assembly is constructed so as to convert the rotary action of the existing lock spindle into a linear and axial movement (push & ull) of thc integral drive bush and so designed that the length of linear travel is proportion:LI lo the angular dcgrce of rotation of the lock spindle and that the drive bush is able to accomodnte various cnd fittings which allow the linear motion bc uansEerrcd to various actuating apparatus.

2. An axial push and pull locking device as claimed in claim 1 whereby the conversion of rotary motion to linear travel is integrally housed within the lock assembly

3. An axial push and pull locking dcvicc as claimed in claim 1 or claim 2 wherin the rotary motion is converted to linear travel via a single or multiple start helically grooved drive bush.

4. An axial push and pull locking device as claimed in any preceding claim whereby the linear motion of the drive bush is enacted by the turning of a security key within the lock assembly.

5. An axial push and pull locking device as claimed in any previous claim which effects linear travel axial to the lock spindle without manual linear movement or spring assistance to the lock barrel itself.

6. An axial push and pull locking device as claimed in any ping claim wherin the linear motion of the drive bush may be coupled directly or indirectly to other apparatus so as to effect a variety of security and safety locking mechanism as cannot be achieved by conventional rotary lock spindles.

7. An axial push and pull locking device as claimed in any preceding claim whereby the drive bush transmits linear motion via a fluid or air medium to a remotely located cylinder or slave cylinder.

8. An axial push and pull locking device as claimed in claim 7 whorl the remotely located air or fluid cylinders perform a latching, catching or switching function capable of being locked in position by the device to which this claim relates.

9. An axial push and pull locking device substantially as described heroin with reference to figures 1-4 of the accompanying drawings.