AU2008100493A4 - Security Screens - Google Patents

Description

00

O

CO

0D

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION Innovation Patent Applicant(s): Roland Clements Invention Title: Security Screens The following statement is a full description of this invention, including the best method for performing it known to me/us: P7779.AU PcgSe1_flng Appkaion 200&5-30dcoc (M) 2 00 Security screens This invention relates to improvements in relation to security screens especially security screens which are attachable to the exterior of windows of vehicles and can be locked thereon to reduce the likelihood of vandalism.

Earth moving machines and vehicles are traditionally too Sbulky to move around and therefore tend to be left on construction sites overnight. The damage caused to such 00 vehicles by vandals is a serious concern and the glass C windows of such vehicles appear to be an attractive target to vandals.

To prevent damage to the windows of such vehicles when left overnight there have been proposed to place security screens over the exterior of the windows and lock those screens in place by use of locking means such as padlocks. The security screens substantially reduce the opportunity for a vandal to break the window and are often designed to define an open mesh. Although the screens are usually removed by the operator before operating the vehicle it is common practice for operators to simply leave the security screens locked in place.

The cabs of earth moving vehicles usually have a rear window which is designed as a safety exit. Because vehicles such as this operate on sites with adverse soil and sloping conditions accidents are known to occur and many accidents occur with the vehicle toppling forwards, jamming the doors, leaving the only method of escape through the rear window.

The cabs of such vehicles often include a hammer or other device to enable the operator to, in an emergency, break the window to effect escape.

Unfortunately however, if the rear window is covered by a security screen which remains locked thereon by use of N:MebaoumeCases satont%770DO-7799'P77793.ALASpoasP77793.AU Specification 2008-5-30.doc 30105108 3 00 0 padlocks, breaking of the window from the inside does not provide a ready access for escape. There have thus been a number of accidents where operators have been killed because it was impossible to escape from the cab due to the presence of security screens locked to the exterior of the windows.

SIt is these issues which have brought about the present invention.

10 According to one aspect of the present invention there is 00 Sprovided a security screen detachably secured to a base C- structure having lugs that engage the opposite ends or sides of the screen, locking means on the exterior of the screen preventing separation of the screen from the lugs, and latch means on the inside of the screen, the release of which facilitates separation of the lugs on one side or end from the base structure.

Brief Description of the Drawings Embodiments of the present invention will now be described by way of example only in which: Figure 1 is an external perspective view of a window frame showing mounting points for a security screen; Figure 2 is a perspective view of the screen when attached to the mounting points; Figure 3 is an inside perspective view of a latch that forms part of a mounting point in a locked position; Figure 4 is a perspective view of the latch in an unlocked position; Figure 5 is a perspective view of a screen mounted on mounting points in accordance with a second embodiment; N:WelboumeXCases \Ptent\77OOO-77999XP77793.AUkSpcisW77793.AU Specifcation 20a8-5-30.doc 30105/08 4 00 Figure 6 is an interior perspective view of a screen mounted on mounting points in accordance with a third embodiment; and Figure 7 is an enlarged perspective view showing the relationship of the lower mounting point of Figure 6 in association with the screen.

As shown in Figure 1 of the accompanying drawings, a mounting Sstructure 10 with projecting lugs 11, 12, 13, 14 is secured by screws, bolts or welding to the top and bottom of the 00 periphery of the window W of the vehicle. The lugs 11, 12, C- 13, 14 extend upwardly at spaced intervals adjacent the corners of the window.

Figure 2 shows a removable security screen 20 made of metal, or very strong plastics, comprises a rectangular frame 21 defining a grid of small, open squares 22. Adjacent to corner of the top of the screen 20 are narrow slits 25, 26 though which the lugs 13, 14 extend. The base of the screen has rectangular cut outs 23, 24 which accommodate right angled brackets 28, 29 which are secured to the screen to project upwardly from the screen to abut the lugs 11, 12 of the mounting structure. The lugs 11, 12 and brackets 28, 29 have coaxial holes 27 which accommodate a padlock 30. At the top of the screen 20, the lugs 13, 14 have a V-shaped profile or extend upwardly so that they extend through the slits 26 in the face of the screen which is lowered onto the incline of the V so the screen can only be removed by first moving the screen 20 up the V and then pulling it away from the lugs 13, 14. This movement can only be effected by release of the padlocks 30 which are attached to the lugs 11, 12 at the base of the screen This is one means for holding a security screen onto the window of a vehicle and causes no problem if the operator of the vehicle is diligent enough to remove the screen every time the vehicle is used. However, because the screen has a N:\MlboumeCses\Patent\77000- 77999\P77Specification 2008-5-30.doc 3=108 00 perforated structure, the vehicle can still be driven with the screen in place and there has been a tendency for operators to leave the screens locked in position which means escape from the interior of the vehicle through the glass becomes impossible because of the fixed location of the screen 20 to the window frame W.

In the embodiment shown in Figures 1 and 2, the lugs 13, 14 at the top of the screen 20 are designed to be held to the mounting structure 10 of a latch assembly 30 (Figure the 00 release of which allows the lug 13, 14 to become detached from the mounting structure 10 and allows the screen 20 to be capable of pivoting outwardly about the lugs 11, 12 at the bottom of the screen 20 by pressure from within.

As shown in Figure 1, the mounting structure 10 comprises an elongate bar 9 with a mounting plate 31, 32 at either end to facilitate secure attachment to the vehicle's window frame W.

As shown in Figures 3 and 4 each base 31, 32 has a rectangular slot 33 through which the end 34 of the lug 13, 14 projects. That end 34 of the lug 13, 14 has a squared aperture 35 which is arranged to accommodate the head 36 of a latch pin 37. The latch pin 37 extends through the end of the lug 13, 14 to hold the lug firmly against the base plate 10. The latch pin is mounted within the bar 9 and is guided for axial movement against a spring 38. A flexible wire cord extends along the bar 9 and is secured to latch pins 37 at either end (although only the left hand side latch pin 37 is shown in Figure 3).

In the locked position shown in Figure 3 the spring 38 urges the head 36 of the pin 37 through the aperture 35 in the end 34 of the lug 13. By pulling on the wire 40 against the spring 38, the head 36 of the latch can be pulled back from out of the aperture 35 in the lug 13, thereby releasing the lug 13, see Figure 4. A pull on the wire 40 pulls both heads back against springs at either end, releasing lugs 13, 14 at N:Wlelboume\Ca seJ3Patent\77000-77999T77793.AUX pSpedftcation 2008-5-30.doc 30/0/08 6 00 either side allowing the operator to then push the screen outwardly so that the top of the screen 20 pivots about the base to define a space sufficient for the occupant to escape from the vehicle. The rectangular bar 9 is of U-shaped s profile with in turned lips 39 and is secured to the end plates 31, 32 to protect the release wire 40 from access from the exterior to ensure against external release.

In the embodiment described above, release of the screen at the top allows the screen to pivot outwardly about the 00 base lugs 11, 12 whilst still providing access for escape of C the occupant of the vehicle.

However, there are certain situations where there are impediments such as an engine cover or filters or exhaust pipes which prevent the screen from pivoting open to a sufficient extent that an occupant can escape from the window. Thus in the embodiment shown in Figure 5, a plate has been fitted to the bottom of the screen 20 which has the effect of moving up the position of the lugs 11, 12 that support the padlocks 50. In other words, moving the hinge point at the base of the screen 20, upwards to allow the screen to swing freely away thus clearing the obstruction of the engine cover and effecting release.

In this embodiment, the plate 50 is of rectangular configuration with the lugs 11, 12 positioned nearer the top of the plate. The plate 50 has mounting means 51, 52 allowing it to be bolted or fastened to the vehicle and, as can be seen from Figure 5, the pivot axis through the lugs 11, 12 is spaced above the base of the plate In the embodiment shown in Figures 6 and 7, a single lug locates the base of the screen 20. The lug projects through a slot 61 in the rectangular mounting plate 50 which has laterally extending mounting points 51, 52 that are screwed or bolted to the frame of the vehicle. A spring loaded wire N:Melbme Casetent\770DO-T79777s\P 7 Specfication 2008-5-30.doc 30/O5/08 7 00 clip 65 extends across the lug 60 to be forced into a groove 62 in one side of the lug to thus prevent the lug from being pulled free of the assembly. The spring is located at either end about mounting points 63, 64. When an occupant wishes to force the screen open, the upper lugs are released in the same manner as described in the earlier embodiments. When M the upper lugs 13, 14 are released, a small force at the top of screen 20 creates a high moment arm leverage to lug Swhich overcomes the tension of the spring. The spring escapes from the groove 62 in the lug 60 and allows the lower 00 lug 60 to be released from the mounting plate 50 allowing the C- screen to be released and fall or be pushed completely clear of the vehicle.

Figure 7 shows the lug 60 in greater detail. The lug 60 has a front flage 71 which abuts the front face of the plate The lower side of the lug 60 has a V-shaped cut-out 72 which engages a similarly shaped projection 73 on the edge of the slot 61 in the plate 50. The rear of the plate 50 also has an angled support flange 75 which engages the end and base of the lug 60 to assure that the lug 60 is firmly and fixedly located within the slot 61 in the plate Thus in the event that the screens remained locked to the exterior of the vehicle and an operator becomes trapped in the vehicle, the operator can break the window, release the latches to disengage the lugs to allow the screen to be pushed open thus allowing release of the occupant.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

N:elboumeses tnt77DD-77999P 77.ALApecisP Specification 2008-5-30.doc 30=ID 8