This invention relates to improvements in devices for hazardous material safety storage cabinets with automatic self-closing and self-locking doors.

Prior Art: It has been known to manufacture safety cabinets for the storage of various hazardous or flammable materials, having features that enable the door or doors to automatically close and lock. None of these inventions allow the doors to move freely beyond that of their restrictive closing mechanism that are unable to exceed an opening capacity of a 180-degree angle.

Safety storage cabinets with dual doors and overlapping seal features require that one door must close before the other. This has been achieved by using a variety of spring, lever and hydraulic mechanisms or by relying on the timing of one door closer in relation to the other door.

All known sequential closing methods have weaknesses that can result in operational failure, consequently eliminating their safety features as follows:

Safety cabinets are subject to diverse commercial industry environments where numerous operators of these cabinets become frustrated with the restrictive 90 or 180- degree door angle mechanisms when attempting to open the doors of these cabinets to conduct simple tasks. Cabinet doors that are forced beyond their fixed closing designed damage varied parts of cabinet structures: doors, hinges, closing mechanisms and cabinet frame structures which inturn causes a various array of additional faults that impact on the ability for the doors to automatically close.

Existing inventions with spring, lever mechanisms have an inability to open the doors past a 180-degree angle. Sequential closing is achieved by a complicated system of levers, bells and cranks mounted on trays under the cabinet's roof and connected with restricted movement to lugs on each door. Some leaver mechanisms limit the door opening to a 90-degree angle. Any attempt to open the doors further causes leaver door anchor lugs to distort which results in misalignment of the leaver mechanism and consequent malfunctioning.

Door closing design inventions that use composite internal topside, split tray sequential closing mechanisms suffer the same opening restrictions as described above, a maximum of 90-degree door opening angle. This split tray mechanism has two metal arms that contact from opposite topsides of the cabinet. One of the metal tray arms moves outside of the trays to come in contact with the other metal tray arm that could cause a naked spark. This moving action can also cause damage to stored containers placed on the top shelves that come into contact with the moving tray arm. Both of these faults eliminate their desired safety function; one function in particular creates an ignition source for fire with the internal contents. Other safety cabinet closing design inventions using a single internal topside tray mechanism have the same opening restrictions as above, again with a maximum of 90- degree door opening angle. These types of mechanisms require care to be taken by opening one door fully before the other. The doors must be opened in a prescribed way to avoid jamming the lever linkage mechanism, when dealing injudiciously with this jamming effect results in damage to the closing mechanism. This damage causes further door, hinge, and structural damages; ultimately the automatic closing mechanism fails disabling the safety function.

Although other cabinet closing design inventions with a combination internal latch, biased spring and hydraulic dampener assembly allow the doors to open to a maximum of 180 degrees, the doors are compromised by the hydraulic dampener and hinges. The position of the hydraulic base mount attached to the top rear wall of the cabinet with the moving arm of that hydraulic to the door disturbs the linkages during the working of the latch rod throughout the function of automatic sequential closing. With the latch rod not engaging the unsealed door, the sealing door will not close flush and causes the failing of the safety seal feature. This design also faults when force is applied to the doors to extract an internal shelf structure. Repetitive disturbances by the hydraulic to the linkages ultimately damage the linkage, latch road and bias spring mount, leaving the cabinet with no form of sequential closing.

Inventions relying on the function of only hydraulic (dual) door closing devices to be speed adjusted so that one closes before another fails the sequential closing action when an operator holds the under-lapping seal door open (to obtain internal contents) allowing the over-lapping door to close flush preventing the safety seal. This closing action is also compromised by the hydraulic door closing devices fluid fluctuations, the loss of fluid thereof, both sealing doors can be altered by the mechanical failure. Impacting weather elements on hydraulic fluids cause changes in door closing speed ratios. The internal closing arm hydraulic devices cause an arm to swing internally, suffering the same fault as other cabinets using theses types of hydraulics with sequential closing mechanisms. Internal contents can be damaged by the swinging action of the hydraulic arms; operators can be injured by closing door high-speed hydraulic fluid fluctuations and leeks.

All of the prior art design cabinets mentioned above are fitted with internal mounted piano hinges, which also restricts the cabinet (dual panel) doors to open to a maximum of 180 degrees. All of the these designs remain in constant contact with their retrospective sequential closing mechanisms creating a difficult restrictive opening action for the operator when conducting simple tasks to access the safety cabinet and contents.

These prior art problems are overcome by the present invention combined with the preferred spring hinge closing function allows the dual doors to open more than 180 degrees with no restraint on the doors. Doors can be opened 270 degrees flush to the cabinet's exterior panel without connection to the sequential closing invention applicable when opening the dual doors creating unrestricted ease of operation when moving internal contents or altering shelf levels, whilst still adhering to the safety features. This invention also provides the option for a safety storage cabinet to have no internal moving parts that can cause damage to the internal hazardous contents.

This sequential closing system invention relates to a dual door bin or cabinet type of construction, a safety storage cabinet for the storage of hazardous and flammable material. The safety feature is to enable the doors to automatically close and lock whilst providing an over-lapping safety seal feature.

The sequential-closing invention is mounted horizontally onto the safety cabinet with the capability of being mounted either: internally, externally or between the cabinets two external and internal panel layers, as per the location of the closing dual doors. There is no linkage between the doors and the sequential closing system device, the doors are free to open 270 degrees to the exterior panels of the cabinet without restriction from the sequential closing invention whilst providing an automatic sequential closing action and safety seal of dual closing doors.

To assist with understanding the invention, reference will now be made to the accompanying drawings, which show one example of the invention.

In the drawings: Figure 1 shows this invention with the dual cabinet doors open ajar before fully closing and numbers all the associated parts.

Figure 2 shows this invention with the dual cabinet doors fully open 270 degrees flush to the outside walls of the cabinet as an example of the unrestricted free movement of the doors.

Referring to Figure 1 with this sequential-closing invention and preferred closing spring hinge there is no exposed internal moving closing arms or metal bars. There is only one sequential-closing locking rod 4 fully enclosed in a metal channel 1, the sequential locking action is made of alloys, preventing any possible damage to or sparking and subsequent ignition of hazardous or flammable materials contained in the cabinet.

The sequential closing invention 1 is mounted horizontally onto the safety cabinet 2 either: internally, externally or between the cabinets two metal skins 17 external and internal layers, as per the location or closing direction of the dual doors 3, 16. Given that there is no linkage between the doors 3, 16 and the sequential closing system / closer check bar channel 1, the doors are free to open 270 degrees to the exterior panels 17 of the cabinet 2 without restriction.

The sequential closing invention materials used are predominantly a composite of metals; these metals can be of alternative material pending the manufactured cabinet application, which can be of alternative materials, metals or synthetics: polyethylene. Predominantly, for a metal cabinet: the use of a steel metal for the closer check bar channel 1 encases the check bar components: locking rod 4, two slide blocks 5, a guide block 6, a tongue block 7 and spring 8. The closer check bar channel 1 will also provide an anchor point for the guide block 6.

The closer check bar channel 1 components consist of: steel metal locking rod 4 at one end is constructed to function as a roller 9 to receive the left side door 16 alloy closer probe lug 10 and is threaded at the opposite end into the alloy metal tongue block 7, this threading also allows the tongue to be variable in length. The locking rod 4 placed through the centre of the first (left side) alloy slide block 5 (this is fixed to the rod) located near the roller end 9. The locking rod 4 continues through (to the right side) the centre of the second alloy slide block 5 (also fixed to the rod) that provides the reverse stopping action onto the anchored alloy guide block 6. This alloy guide block 6 is anchored to the check bar channel 1.

The locking rod 4 moves freely through the anchored guide block 6, which is the base for the metal spring 8 applying the reverse action to the locking rod 4, and tongue block 7, the locking rod 4 continues through the spring 8 into the tongue block 7. The tongue block 7 receives the right side door 3 alloy closer probe lug 11 causing the sequential function, holding the right door 3 ajar before the left door 16 can close flush to the front of the cabinet 2. Once the left door 16 closes flush to the front of the cabinet 2 and activates the roller 9 / locking rod 4, inturn pulling the right door 3 tongue block 7 back allowing the right door 3 to close after the left door 16 causing the sequential-closing action and safety seal 15 of the two doors 3,16.

The door closer probe lugs 10, 11 are attached to a specific position on each door 3, 16 pending the mounting of the closer check bar channel 1 and internal components. The left door 16 probe lug 10 is of design shape to pull on the locking rod 4 / roller 9, specifically to activate the roller 9. The right door 3 probe lug 11 is of design shape to firstly cushion the door 3 before resting on the tongue block 7 with it's protruding edge. The probe lug 11 cushion is adjustable to assist with future maintenance. Both lug positions on the doors will not exceed that of internal cabinet shelving when the doors are in the fully closed position, applicable to any internal mounting of the closer check bar channel 1 and components.

These doors close from left to right as a commonly manufactured with the over lapping door seal 15. The invention can operate in reverse depending the manufactured over lapping seal 15 of the doors 3, 16.

There is an amount of air pressure applied internally from the rear area of the cabinet 2 as both doors 3, 16 close, which can push open the left door 16 just prior to full closure. This is counter-acted by a magnet 12 and fixed to the exterior of the check bar channel 1 and an opposing contact plate 13 fixed to the interior of the left door 16 which both pull the left door 16 to a flush position at the front of the cabinet 2. This would be applicable to any cabinet material structure to assist with door closing.

This sequential closing invention works independently from other optional prior art door closing devices as follows:

The preferred spring hinge 14 closing function option is a biased metal spring housed in steel tubing and fixed to a boss steel hinge mounted vertically on the exterior of the cabinet (the hinge fixed to the door) for maximum opening benefit. This application can also be mounted internally or be made of other composite materials depending on the cabinet application. The longer the length of the spring provides a softer closing action and offers no reverse force found with hydraulic closing options. In addition to being fault and maintenance free the spring hinge closing function can be easily removed to allow the doors to be taken off for maintenance, repairs or replacement. The soft closing action also provides a safer working cabinet with no internal working hazards, reduces the risk of damage to internal contents and prevents the user from injury which occurs with a hydraulic option that is prone to the loss of fluid.

An alternative prior art door closing function is an isolated hydraulic door closing devise. The hydraulic door closer can vary with existing inventions applicable to the particular manufactured safety cabinet designs and their relative construction materials, it can be mounted according to its' design function. In case of strong wind environments impacting on the closing of the doors this closing option may be preferred.

Adaptations on the spring hinge could be that of other prior art designs where the spring closing device is mounted separately to the hinge and attached to the door then internal cabinet structure. The preferred spring hinge 14 option conserves the amount of surface area used and works directly with a boss hinge.

Prior art automatic self-locking door handle devices differentiate with each cabinet manufacturer and vary with each cabinet door and frame design. These self-locking door handle designs work independently to this sequential-closing invention or preferred door-closing function. The specific action of the automatic door-locking handle to the cabinet frame is self-operating and can function independently with any automatic door closing invention.