GB2187497A

GB2187497A - Security lock for a door

Info

Publication number: GB2187497A
Application number: GB08605206A
Authority: GB
Inventors: Ronald Henry Gealy; Lionel John Smith
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-03-03
Filing date: 1986-03-03
Publication date: 1987-09-09

Abstract

A locking system for a hinged door comprises a pair of bolts 3 mounted for longitudinal horizontal movement on a back plate 1, which extends substantially across the width of the door and an operating mechanism which includes an operating handle secured to a slide 5 moveable vertically between two positions to urge the bolts 3 into or out of engagement with the door frame. Movement is transmitted from slide 5 to bolts 3 via pivoted links 6. The system may be mounted on or in the door and movement of the slide 5 may be controlled additionally by a solenoid operated via switches, push-buttons or a security circuit responding to magnetic tape or card key. <IMAGE>

Description

SPECIFICATION Door lock This invention relates to a security locking arrangement for a hinged door.

The invention provides a locking system for a hinged door, openable within a fixed frame and comprises a pair of latch bolts mounted on a back plate for longitudinal movement on a horizontal axis, an operating mechanism which includes a handle moveable vertically between a first position in which the latch bolts are retracted and a second position in which the bolts are moved apart to engage with the door frame to secure the door in a locked position.

These and other features will now be de- scribed by way of example with reference to the accompanying drawing of which Figure 1 is a diagramatic view with the outer case removed and showing the operating mechanism of the lock in accordance with the invention.

Figure 2 is a similar view of the lock with the outer case in position.

Referring to the drawings the locking system comprises a back plate 1 of channel section having spaced guide members. 2 adapted to guide and retain two rectangular section latch bolts. 3 The latch bolts slide within the guide members and are moveable relative to each other and the back plate.

Each bolt is connected to a slide block 5 by a link member 6 the link members are mounted on a pivot pins 7 at each end such that vertical movement of the slide block 5 will move the latch bolts longitudinally within the guide members.

A channel section cover plate 8 fits over the back plate and encloses the slide block, guide members and latch bolts.

A slot 9 formed in the cover plate acts as a guide channel for the slide block. The slot is shaped in the form of a inverted L and the slide block has an upstanding portion 13 which engages with and slides within the guide channel. Preferably the upper arm of the slot is shaped to provide an indent 10 to return the slide block in its uppermost position.

A handle or knob 11 may be attached to the slide block in a conventional manner.

In the preferred embodiment, the back plate 1 is secured to the surface of the door by screws and extends substantially across the full width of the door. Locking plates 12 dimensioned to receive and engage the latch bolts are fitted to the vertical members of the door frame on each side of the door opening.

In operation, with the door closed but not locked the knob 12 will be in the lower position at the bottom of the vertical slot 9.

Upward movement of the knob moves the slide block within the slot, the link plates 6 push the latch bolts apart and the end of each bolt engages with the locking plates on each side of the door frame. Slight sidewards movement of the knob allows the slide block to enter the detent and hold the latch bolts in the "door-locked" position.

The latch bolts will thus remain in the "door-locked" position until a deliberate upward and sideways Movement of the knob is made to clear the detent and then move the knob vertically downward to withdraw the latch-bolts and unlock the door.

Although in the preferred embodiment of the invention the lock has been described as an attachment to the door surface it will be understood that the lock may be incorporated with the thickness of the door or it may be included as a constructional and strengthening feature of the door during the process of manufacture.

As an additional feature, movement of the slide block may be controlled by an electric solenoid and operated through switches, push buttons or an electronic sensing circuit using magnetic tape or card keys.

1. A locking system for a hinged door which is openable within a fixed frame comprising a pair of latch bolts mounted for longitudinal movement on a horizontal axis an operating mechanism including a handle, movealbe vertically between a first position in which the latch bolts are retracted and a second position in which the bolts are moved apart and engage with the frame to secure the door in a locked psoition.

2. A locking system according to claim 1 wherein said latch bolts are moveable within guide members on a back-plate adapted for attachment to the operating mechanism comprises a slide block engageable with the handle a link plate pivotally connecting each bolt to the slide block such that movement of the slide block causes the bolts to slide within the guide members.

3. A lock system as claimed in claim 2 wherein the back-plate, guide members locking bolts and the slide block are enclosed within an outer case and a slot formed in the outer case provides a guide channel for the slide block.

4. A locking system according to claim 1 wherein the guide channel is shaped to provide a detent position for the operating handle when the latch bolts are extended in the locking mode.

5. A locking system according to any preceding claim wherein the back plate is adapted for attachment to the surface of a building door, is dimensioned to extend substantially across the width of the door and locking plates are mountable on the vertical members of the door frame to engage and receive the end of the latch bolts.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Door lock This invention relates to a security locking arrangement for a hinged door. The invention provides a locking system for a hinged door, openable within a fixed frame and comprises a pair of latch bolts mounted on a back plate for longitudinal movement on a horizontal axis, an operating mechanism which includes a handle moveable vertically between a first position in which the latch bolts are retracted and a second position in which the bolts are moved apart to engage with the door frame to secure the door in a locked position. These and other features will now be de- scribed by way of example with reference to the accompanying drawing of which Figure 1 is a diagramatic view with the outer case removed and showing the operating mechanism of the lock in accordance with the invention. Figure 2 is a similar view of the lock with the outer case in position. Referring to the drawings the locking system comprises a back plate 1 of channel section having spaced guide members. 2 adapted to guide and retain two rectangular section latch bolts. 3 The latch bolts slide within the guide members and are moveable relative to each other and the back plate. Each bolt is connected to a slide block 5 by a link member 6 the link members are mounted on a pivot pins 7 at each end such that vertical movement of the slide block 5 will move the latch bolts longitudinally within the guide members. A channel section cover plate 8 fits over the back plate and encloses the slide block, guide members and latch bolts. A slot 9 formed in the cover plate acts as a guide channel for the slide block. The slot is shaped in the form of a inverted L and the slide block has an upstanding portion 13 which engages with and slides within the guide channel. Preferably the upper arm of the slot is shaped to provide an indent 10 to return the slide block in its uppermost position. A handle or knob 11 may be attached to the slide block in a conventional manner. In the preferred embodiment, the back plate 1 is secured to the surface of the door by screws and extends substantially across the full width of the door. Locking plates 12 dimensioned to receive and engage the latch bolts are fitted to the vertical members of the door frame on each side of the door opening. In operation, with the door closed but not locked the knob 12 will be in the lower position at the bottom of the vertical slot 9. Upward movement of the knob moves the slide block within the slot, the link plates 6 push the latch bolts apart and the end of each bolt engages with the locking plates on each side of the door frame. Slight sidewards movement of the knob allows the slide block to enter the detent and hold the latch bolts in the "door-locked" position. The latch bolts will thus remain in the "door-locked" position until a deliberate upward and sideways Movement of the knob is made to clear the detent and then move the knob vertically downward to withdraw the latch-bolts and unlock the door. Although in the preferred embodiment of the invention the lock has been described as an attachment to the door surface it will be understood that the lock may be incorporated with the thickness of the door or it may be included as a constructional and strengthening feature of the door during the process of manufacture. As an additional feature, movement of the slide block may be controlled by an electric solenoid and operated through switches, push buttons or an electronic sensing circuit using magnetic tape or card keys. CLAIMS

6. A lock for a door substantially as herein before described with reference to the accompanying drawing.