Open sesame!

Latch secures items in two planes

PROBLEM: The challenge was to create a seal on a door or access panel using a lever action fastener or drawlatch. The action of a conventional over-center type fastener is well understood and perfectly adequate for the purpose of securing together two items such as a locker lid or door. However, it does not force down the lid, panel, or door against the seal.

SOLUTION: The Protect ProLatch(TM) fulfills the basic function of an over-center type fastener while at the same time applying a compressive force, thus securing items in two planes.

Its simple design incorporates a safety catch that holds down the lever component. To produce a compressive force, the loop wire "claw" creates a fulcrum effect between the two flanges on the lever and the separate catchplate component.

It is available in either stainless steel or mild steel with a yellow/iridescent-colored zinc chromate finish. The latch can also be pin-sealed or padlocked for added security.

According to the manufacturer, the ProLatch(TM) can save significant costs in the manufacture or fabrication of designs by eliminating the need for complicated seals, flanges and other components normally required to achieve the sealing effect.

APPLICATIONS: The ProLatch(TM) is useful in securing EMI/RFI shielding and other types of enclosures. The option of stainless steel makes it suitable for the chemical, pharmaceutical, food, and marine industries, to prevent contamination or moisture ingress in plant equipment. Protex Fasteners, Ltd., Arrow Rd., Redditch, Worcester, England B98 8PA:

Enclosure latching system requires lower handle torque.

PROBLEM: Since enclosure doors may be accessed frequently for operation or diagnostics, a secure latching system with low torque is desirable to reduce operator fatigue. A design constraint was the very narrow frame profile of PROLINE modular enclosures compared to existing modular enclosure frames. The final design also had to be compact, durable, and economical.

SOLUTION: The Hoffman PROLINE latch is a patented, three-point system using a latch rod geared to a handle cam to close access doors on PROLINE modular enclosures. When the pop-up handle is turned, the geared cam engages teeth on the latch rod, moving the rod up or down. The latch rod has three "fingers" with rollers that ride up and over ramped latch-catches on the frame jamb.

The design has several unique features. The latching mechanism creates a secure UL Type 12 seal between the knife-edge frame flange and a foam-in-place gasket on the door. To achieve adequate gasket compression, it requires lower handle torque than previous designs. For secure latching, the roller fingers have a hook and roller design, and there is an independent locking mechanism for added security. A push button actuates the spring-up handle, which can swing right or left.

APPLICATIONS: The latching system is widely available on PROLINE Modular Enclosures through Hoffman's network of 1,400 North American distributors. Hoffman:

Vise action latch fits in small places

PROBLEM: In some applications that require compression, there is little room inside the compartment or box for the latch mechanism to function without interfering with wiring and other internal contents.

SOLUTION: Southco's new Short Shaft Vise Action(TM) compression latch has 23 mm less protrusion than a traditional vise action latch. It operates in a single half-turn, first locking the door and then pulling it up tight. With a fraction of a turn, the latching pawl swings smoothly into place behind the door. When the half-turn is complete, the latching pawl moves toward the door, pulling it up tightly against the frame and applying compression. The latch applies consistent pressure of up to 6.4 mm compression to help seal EMI or environmental gasketing. It also helps to eliminate rattles.

The Vise Action latch is unique among compression latches, says Southco, because the pawl pulls up against or perpendicular to the frame, rather than rotating behind it. A pawl rotating behind a door can cause "grinding" and eventual corrosion. Over ten head style options include the railway standard, 7 mm square, 8 mm square, and M4 triangle. For the first time, a stylized knob head style is also available. Pawls come in a variety of lengths, with grip ranges up to 53 mm to fit most any frame or door configuration.

APPLICATIONS: Any application in which inside protrusion is a concern, including enclosures for electronics, HVAC, computer, rail, and bus components. It is also suitable for luggage and storage compartments on high-speed trains and buses. Southco:

Lobe knob looks good, keeps out contaminants

PROBLEM: In sanitary applications, such as food and medical, contamination is a concern. Knobs must contain no exposed voids, while at the same time have good aesthetics.

SOLUTION: RENCOL's Lobe Knob is a full-featured thermoplastic knob. A two-part molding process conceals its internal cavity, resulting in a visually-pleasing knob with a robust solid appearance and no exposed voids. The knob comes in a standard black matt finish and also a wide range of optional colors that can be coordinated with specific applications. It is available in female and male projections in sizes 40, 50, 60, and 75 mm.

APPLICATIONS: Medical, pharmaceutical, and food industries or other applications where sanitation and aesthetics are key concerns.Rencol 216-218 Southmead Rd., Bristol B510 5EB U.K. or DFS International (U.S. distributor for RENCOL):

High security shootbolt stops theives short

PROBLEM: Within three minutes, an experienced thief can break through a window. Security hardware must resist at least 3000N of applied force, test to 50,000 cycles, and resist corrosion.

SOLUTION: Securistyle's Vector Total Security Package incorporates a shootbolt, handle, and hinges to meet stringent security requirements, yet maintains the look and feel of a door locking mechanism. Rather than a cam system, it incorporates a tri-directional gearbox with a deadbolt in the center and a shootbolt at the corners. The system's 13 die-cast components are made of one of three zinc alloys that provide the required strength and finish. The gearbox, for example, withstands over 35 N-m handle torque. Fishercast-Division of Fischer Gauge Ltd. supplies the zinc alloy die castings, which are cast net-shape with no flash, so there is no secondary finishing required.

APPLICATIONS: Security for residential windows. Security system from Securistyle Kingsmead Inds Estate, Princess Elizabeth Way, Cheltenham, Glos. U.K.:

Die castings from Fishercast-Division of Fisher Gauge Ltd PO Box 179, Peterborough, Ontario, Canada K9J 6Y9:

Pull-action clamps provide quick closure

PROBLEM: Lids, doors, and other closure devices require secure locking, yet at the same time require easy access.

SOLUTION: De-Sta-Co's family of pull-action manual clamps is available with a horizontal pull action or vertical pull action. Their over-center toggle-locking action suits them ideally for holding against heavy forces. One hand is used to engage or disengage the latch bar while the other moves the handle. Holding capacities range from 375 to 7,500 lbs. The Toggle Lock Plus configuration incorporates a special lever that enables locking of the clamp after it's latched. Threaded U-bolts on another model (shown) permit easy adjustment and provide a positive connection with the supplied latch plate. All models are supplied with an ergonomic handle grip.

APPLICATIONS: Designed for holding against heavy forces, such as those generated in plastic molding operations. Also ideal for quick clamping of doors, lids, or access covers onto drums, containers, and other vessels.

De-Sta-Co:

Weld-on hinge eliminates extra hardware

PROBLEM: In tight-fitting situations, traditional hinges are cumbersome. Designers wanted a hinge that eliminated the need for fasteners and leaves.

SOLUTION: The slim-profiled Guden Weld-on Hinge offers continuous, smooth operation. It produces less sag than butts and slip joints, an important feature for doors or lids that are inset and must fit properly. Parts also have less side play, and a better axial arrangement. In many cases, this hinge can replace butt or slip hinges and is particularly useful in tight-fitting applications. The hinge is available in 12 sizes, from 1.56 to 10 inches long, and can be configured in several different ways. It comes in all standard materials, including steel, stainless steel, and aluminum.

APPLICATIONS: Weld-on hinges are ideal for a wide range of applications, including all types of enclosures, containers, and equipment.

H.A. Guden Co., Inc.