GB2313104A

GB2313104A - Manually operated landing gate lock

Info

Publication number: GB2313104A
Application number: GB9610421A
Authority: GB
Inventors: Jeffrey John Gunn
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-05-17
Filing date: 1996-05-17
Publication date: 1997-11-19
Also published as: GB9610421D0

Abstract

A manually operated device which allows an operative to unlock a goods hoist landing gate when the hoist platform is in position at that landing level. To operate the device an operating lever (1) is depressed, this causes the roller (5) to make contact with the platform (12) thus pushing a retracting bar (2) up the inside of the operating lever (1) causing an activation pin (7) to fully rotate a switch arm (8) thereby unlocking the landing gate. If the operating lever (1) is depressed when the platform (12) is not in position, the retracting bar (2) does not move up the inside of the operating lever (1) thus preventing unlocking of the landing gate; however this does cause partial rotation of the switch arm (8) which breaks the gatelock electrical circuit and stops the platform running, thus preventing a moving hoist platform striking the projecting roller (5)

Description

MANUALLY OPERATED LANDING GATE LOCK This invention relates to a manually operated landing gate lock, generally for use with construction site goods hoists.

A goods hoist is used to transport goods vertically from one landing level to another. At each landing level there is a landing gate, which is opened from the landing to gain access to the hoist platform. To prevent the operators falling from a landing through an open gate, a lock can be fitted to the gate which prevents the gate opening until the platform is at that landing level. Existing designs of locks unlock the landing gate automatically whenever the platform stops at the landing level. This unlocking is triggered by means of an electrically operated retiring ramp that is fitted to the platform. This combination of gate lock and retiring ramp has proved to be unreliable when in use on construction site goods hoists due to the difficulty in setting and maintaining the accurate alignment that is required for this combination to operate.

This invention converts existing landing gate locks to manual operation, thus eliminating the need for a retiring ramp on the platform, and allowing greater positional tollerance when fitting the gate lock.

The operation of this invention will now be described with reference to the following drawings and parts list.

Fig.l Shows a plan view of the landing gate, the lock and the platform. The landing gate is locked.

Fig.2 Shows a side view of the lock and platform. The landing gate is locked.

Fig3 Shows a side view of the lock. The operating lever is depressed. The operating lever switch is open. The landing gate is locked.

Fig.4 Shows a side view of the lock and platform. The operating lever is depressed.

The operating lever switch is open. The landing gate is unlocked.

Fig.5 Function Table.

PARTS LIST

(1) Operating lever (2) Retracting bar (3) Carrier plate (4) Compression spring (5) Roller Manually Operated (6) Roller shaft r Landing Gate Lock (7) Activation pin (8) Switch arm (9) Gatelock (10) Beak (11) Landing Gate (12) Platform (13) Landing Gate Frame Refering to the drawings the Manually Operated Landing Gate Lock (items 1 to 10) comprises of a Carrier plate (3), which is fixed to the Landing Gate Frame (13), an Opearting lever (1), which pivots on the Carrier plate (3), a Retracting bar (2), which slides within the Operating lever (1), a Compression spring (4), which pushes the Retracting bar (2) into its extended position, a Roller (5), which contacts the platform when the Operating lever (1) is depressed, a Roller shaft (6), which allows adjustment of the Roller (5) in two planes, an Activation pin (7) which retains the Retracting bar (2) within the Operating lever (1) and partially pushes the Switch arm (8) when the Operating arm (1) is depressed, which opens the Operating lever switch inside the Gatelock (9). The Gatelock (9) which contains the Operating lever switch, and the Beak switch which are connected in series, a Beak (10) which is fixed to the Landing Gate (11). The front of the Beak (10) slides into the Gatelock (9) and is locked there until the Operating lever (1) is depressed whilst the Platform (12) is stationary at landing level, causing the Retracting bar (2) to retract and the Activation pin (7) to push the Switch arm (8) fully round.

ELECTRICAL FEATURES A manually operated Landing Gate lock is installed at each landing level. The Gatelocks are connected together in series (through the two normally closed switches in each Gatelock) to a contactor in the goods hoist control panel. If any switch opens, the hoist platform will stop.The hoist platform will not run until all switches in the Gatelock circuit are closed and the circuit is complete. A completed Gatelock circuit can only be achieved when all the Landing Gates are closed and when all the Operating Levers are in their free positions (not depressed).

Claims

1. A manually operated Landing Gate lock which enables a Landing Gate to be opened from the Landing only when the hoist platform is stationary at that landing level. By means of a Roller fixed to a Retracting bar which slides within an Operating lever. When the lever is depressed the roller rolls up the Platform causing the Retracting bar to retract causing the Activation pin to rotate the Switch arm fully, causing the Landing Gate to unlock.

2. A manually operated Landing Gate lock as claimed in claim 1. wherin movement of the Operating lever will cause the hoist Platform to stop or prevent it from moving by means of a switch operated by partial rotation of a Switch arm. The Switch arm is caused to rotate by an Activation pin which is positioned off centre of the Operating lever pivot.

Thus when the Operating lever is depressed the switch opens. The position of the Activation pin is such that when the Operating lever is depressed, the Switch arm rotates only partially causing the Landing Gate to remain locked.