GB2404421A

GB2404421A - Timer controlled letterbox lock

Info

Publication number: GB2404421A
Application number: GB0317611A
Authority: GB
Inventors: Philip John Waterhouse
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-07-28
Filing date: 2003-07-28
Publication date: 2005-02-02
Also published as: GB0317611D0

Abstract

A letterbox lock includes a timer (4) which controls the movement of a geared motor driven bar assembly into and out of (Figure 2) a letter box aperture (6) such that the plate may only be opened at predetermined times. The lock may be mounted on a back plate (1) which is mounted around the letterbox aperture. The bar assembly (2) is adjustable in length (12, 13) to accommodate letterbox apertures of different depths and may be disengaged from the motor to allow the lock to be set up correctly.

Description

240442 1 TIMED L,ETTERBOX LOCKER The invention relates to a device that

incorporates an electro- mechanically operated bar that is electronically controlled via a timing unit, to move into a position such that it prevents the inwards opening of a flap or door into a small domestic or non-domestic aperture.

An obvious example of such an aperture would be a letterbox.

The object of this invention is to provide a means to control at pre programmed times on a day(s), outside access to opening the letterbox door.

i.e.: I he ability to prevent the passage of items such as mail through said opening at times other than that desired.

Accordingly this invention provides a user programmable timer unit, for every day of the week, as well as a geared motor driven closure bar that when activated moves into position in front of the letterbox door to prevent opening of said door for a user set length of time.

A manual over-ride facility on the invention enables the user to open or close the aperture at a desired time without the need for the timer unit to be re-programmed.

The geared motor,closure bar and timer unit are mounted on a flat back plate and this whole unit is then fitted to the back end of the aperture.

Preferably the whole unit is made of plastic and metal, but the back plate may be made of wood to more aesthetically suit a wooden surface to which the unit is to be attached.

A preferred embodiment of the invention will now be described with r eference to the accompanying drawing in which: FIGURE I shows a front perspective of the entire device.

I;lGlJRE 2 shows a side section showing the device in place at the back end of a domestic door letterbox. The device is NOT in activation mode (the closure bar has not been moved in front of the aperture, and thus the aperture is open).

FIGURE 3 shorts a side section showing the device in place at the back end of a domestic door letterbox. The device is in activation mode (the closure bar HAS been moved in front of the aperture, and thus the door cannot open).

FlGllRF 4 shows a simplified wire framed 3-D perspective of the closure bar assembly.

As shown in Figure 1 the device comprises a back plate 1 with a closure bar assembly 2 below a user adjustable aperture 6. The aperture has prestressed removal plastic edges 10 to allow for a customizable aperture width.

The geared motor 3 drives the closure bar 2 into the aperture 6 under control of the timer unit 4.

I'he fixed bearing 5 allows the closure bar free mobility and rigid support as the geared motor 3 rotates bar 11, which in turn drives closure bar assembly 2 into it's position in 6. An attempt to open the aperture door when the closure assembly is activated will result in a force being directed to the drive bar I I and the fixed bearing 5, and geared motor 3. The resultant torque provided by the static motor and the gear mechanism provides any back rotation of the drive bar 11, and thus prevents the aperture door from being allowed to open into the aperture.

When installing the invention, tile drive bar can be dis-engaged from the motor, to allow the closure bar assembly to be set to the desired aperture via adjustments of 12 and 14.

Both 3 and 4 are supplied a D.C (direct current) voltage via power supply 7.

Mounting holes on the bacl; plate are indicated by 8, and pre-stressed removal plastic 9 on either side of 6 and 10 are to allow for letterbox attachment bolts which may be present, to pass through back plate 1.

Figure 2 shows the closure bar 2 in it's un-activated position. T he aperture door has free motion unhindered by the invention.

Figure 3 shows the closure bar 2 in it's optimal activated position, with it's front edge as near to the edge of the aperture door 15 so as to provide the desirable maximum leverage force that it can against the force of the door opening.

Figures 2 and 3 show the adjustable feature 12 of the closure bar assembly 2, which may consist of a tightening collet 13 over an extendable or telescopic tube arrangement. This adjustment could be necessary for apertures with varying depths, to allow 2 to move into a close proximity (activated) position 15 to the aperture door, thus preventing it opening as seen in Figure 3.

Figures 2 and 3 also show the adjustable angled feature 14 of the closure bar assembly 2. This user adjustably tightened joint which may be ratchet based, along with adjustable feature 12 allows the front edge of closure bar 2 to be positioned as close in activated position to aperture door position 15 as possible. 16 and 17 also indicate the direction of mobility that the assembly has BEFORE 12 and 14 are LOCKED tightly.

Figure 4 shows the positioning of the geared motor attachment, the drive bar and fixed bearing. The general positioning of the user adjustable angled joint and the user extendable tube arrangement can also be seen.

Claims

1. A permanently fitted device providing a method of automatic control over access to an inwardly opening door fronted aperture such as a domestic or industrial letterbox, by utilizing an electronically timed geared motor to move a mechanical assembly into the aperture and provide resistance to opening of said door into aperture.

2. Permanently fitted as claimed in CLAIM 1 where once the invention is attached to the back end of the aperture, it is not a portable device unless removed.

3. Automatic control over access as claimed in CLAIM I where the user has full twenty-four hours a day, seven days a week access to the aperture by user programmed means or over-ride means.

4. Electronically timed as claimed in CLAIM I Or CLAIM 3 where the user has the ability to program the device so the assembly can enter the aperture for a specific time period, and therefore block access to the aperture.

5. Closure assembly es claimed in CLAIM 1 that comprises fully user adjustable and lockable linkages to enable the said assembly to be adjusted to fit the required sized aperture letterbox.

6. Resistance to opening as claimed in CLAIM 1 as indicated by the closure assembly moving into a position close to the aperture door, so as to prevent the door from opening. /

7. The invention as claimed in any preceding claim that is electronically controlled to provide an electro-mechanical means to bar passage of material through an aperture such as a letterbox, via an inward-opening door. r l

8. The invention as claimed in any preceding claim which is made from metal, plastics material or wood, or from a combination of these materials.

9. A time locked aperture or letterbox substantially as herein described above and illustrated in the accompanying drawings.

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