Switches, Signals, and Connectors 14870

Originally Published MPMN January 2004

SPOTLIGHT

Switches, Signals, and Connectors

Slide components

Available in surface-mount or through-hole versions, compact slide switches featuredouble-pole capabilities in a single-pole body. The Alcoswitch units can be ordered unsealed orwith an IP67-rated seal. With printed circuit board retention features and a robust actuator,the components offer repeatable performance for up to 10,000 cycles. The contacts within the switches are rated for 0.4 VA at 20 V dc with an initial contact resistance of less than 50mW. The contacts are phosphor bronze with gold over nickel plating, and offer actuation force rangesfrom 70 to 500 g. Tyco Electronics, Harrisburg, PA; www.tycoelectronics.com 

Miniature switches

A line of miniature and subminiature PC-mount and sealed switches includes rocker, toggle, push-button, and slide options. Many of the components are also availablefor surface-mount applications, are sealed to an IP67 rating, and are UL/CUL certified. Acatalog of the miniature switches is available, detailing product features and specifications.Carling Technologies Inc., Plainville, CT; www.carlingtech.com 

Motion switches

Miniature switches sense motion, acceleration, impact, and other disturbances. Their current-handling capacity ranges from milliamps to amps, and sensitivity ranges from fractional to several thousand forces of gravity. Multiple configurations are available, and the switches can be oriented for linear, angular, or hemispherical sensing. Hermetically sealed 
for long life and reliability, the components are easily mounted to printed circuit boards. 
Aerodyne Controls, Ronkonkoma, NY; www.aerodyne-controls.com 

Key switches

Key switches are available in a range of models and sizes, and with various options. They offer vibration resistance and guaranteed switching. The K6 and K12 models' switching voltage ranges from 2 to 30 V dc, and their switching currents range from 10 µA to 100 mA dc. The K12 series features standard travel lengths of 1.0, 1.5, and 2.0 mm, and a service life in excess of one million cycles. A special contact system enables the button travel, tactile snap point, and operating force to be engineered to custom applications. The K6 switches offer travel lengths from 1 to 1.5 mm, and are available in four versions, with and without an LED. With a smaller footprint than earlier versions, the components require a printed circuit board space of 10.9 ¥ 7.4 ¥ 8.4 mm. The life span of the K6 models exceeds 200,000 cycles. ITT Industries, Cannon, Newton, MA; www.ittcannon.com 

Hybrid connectors

Mixing multipurpose contacts in one connector body provides design flexibility. The contacts can be assembled into a variety of configurations. With more than eight standard bodies to choose from, capabilities include fiber-optic, fluid or gas, high-voltage, and high-current options. The hybrid line can be optionally sealed to an IP68 rating; a number of options and accessories are available.Fischer Connectors, Alpharetta, GA; www.fischerconnectors.com 

PCB terminal block

A high-power printed circuit board (PCB) terminal block is based on screw-clamp technology. The MKDSP 25 enables the connection of large conductors directly to the PCB, typically found in ring-tongue and panel-mount applications. The component is available in a single position or preassembled in two to nine positions. In addition to offering screw-mounting flanges to the PCB, the terminal block has a current capacity of up to 125 A at 600 V, and accepts #20 2 AWG wire. 
Phoenix Contact Inc., Harrisburg, PA; www.phoenixcon.com 

Sensor arc

A device with a curved, one-piece, flexible sensing edge provides contact closure when touched at any point. Sensor-Ring is suitable for medical scanning heads, and replaces multipiece, multiswitch components. The sensing edge is located on the circumference of a hollow arc or ring, enabling the pass-through of wires, mechanical components, or personnel. Available in diameters of 1.5-5 ft, the component covers an angular range from 10° to 360°. The connection is made with a stainless-steel armored cable, and sensors can be installed on up to three sides of the ring. Classified with an IP67 rating, the switch is protected against dust and immersion.Tapeswitch Corp., Farmingdale, NY; www.tapeswitch.com 

I/O connector

A microcircular connector has been developed in response to the growing need for ruggedness inmedical equipment. Designed for use in harsh environments, the JB5 series offers waterproofsealing with an IP68 rating and a secure push-pull mating system. With solder terminals and a lightweight aluminum alloy shell, the connector is available with from 2 to 25 contacts. Each contact features a current rating of 2 A, a 200-V-ac dielectric withstanding voltage, and a temperature range of -55° to 85°C. 
JAE Electronics Inc., Irvine, CA; www.jae.com 

Terminal blocks

Compact sensor or terminal blocks are suitable for control panels or junction boxes with limited space and persistent vibration. Front-entry wiring of the 270 series facilitates assembly, and the company's Cage Clamp for conductors ensures a vibration-proof connection. The jumper system with slots to accommodate noninsulated push-in jumper bars protects against accidental contact. Jumpers are available in 2- through 17-way versions for power distribution. An optional LED indicates the status of and locations for marker cards to ensure secure connections.Wago, Germantown, WI; www.wago.com 

Emergency stops

Panel-mounted switches are available in twist-to-release and key-to-release options for emergency-stop operations. The 04, 61, and 44 series of the EN 418 E-Stops are designed with a mechanism to prevent the switch contacts from operating if the mushroom head is not fully actuated. The 22.5-mm mounted 04 and 44 switches have 37-mm-diam actuators. The 04 model incorporates a bayonet-fitting contact block with two mounting screws, while the 44 series has a snap-on contact block. Installed using a threaded shaft and lock nut,the 61 model measures 16 mm with a 27-mm-diam actuator. Accessories include emergency-stop labels and enclosure boxes.EAO, Milford, CT; www.eaoswitch.com 

Copyright ©2004 Medical Product Manufacturing News