January 14, 2019

Liftgate Engineering for Work Trucks

Liftgate manufacturers need to contend with a great many variables as they seek to make their hydraulic lift assemblies operational on the widest possible variety of vehicles. Is it a pickup truck, straight truck, van, or trailer application being used? What are body widths? Will it be a swing up platform or a stowaway gate? What ground clearance and load must it support? Will it cantilever to support uneven ground? The list of considerations goes on well beyond these and fleet managers need to consider all them when designing liftgate solutions for their work trucks.

One thing however that seems to be more agreed upon are the requirements of the platform activation switches. These are typically mounted in a fixed position on or near the liftgate. As such they are often exposed to the same conditions as the outside of the vehicle itself, namely rain, mud, dirt, wind, vibration and temperature extremes. Given the propensity for operators to ride up and down on the liftgate, they are often designed to go for the ride too.

CPI Switches and Panels for Liftgate Control

Because CPI’s switch construction is truly waterproof, not just splash-proof or water resistant, we can create assemblies out of our totally submersible basic switches and stainless steel panels that are perfect for a wet outdoor environment. Our assemblies are used in outdoor applications including lift gate up/down control, construction and mining equipment, as well as engine compartments in transit buses.

Most commonly used for liftgate control and positioning is our E1333 series dual pushbutton switch panel to raise and lower the lift gates. The E1333 provides a short behind the panel depth requirement making it usable in places where other switches can’t fit. The CPI switch also provides low assembly labor to install with its integral PEM nuts and its packard connector. Lastly as opposed to electronic switches that require power from the circuit to operate the discreet CPI switch is resistant to failures due to poor grounds and its high electromechanical endurance. In fact our “snap action” contact design has been tested to over 500,000 “contactor” electrical cycles.

Don’t worry about lead lengths either. Our switches and switch panels can be ordered from the factory at any custom lead length you need.

The ability of our switch to withstand abuse at the hands of an operator or mother nature, really sets our products apart for most outdoor applications. And with convenient custom or stock panels, there’s one less piece of engineering you need to do.

CPI Custom Waterproof Switch Panels

Switch panels come in a variety of configurations: separate circuits, in-series, and in-series with interlock (to prevent both switches from operating at the same time).

We can produce multiple switch panels that also include additional electrical components such as LED indicator lamps per customer specification.

CPI Waterproof Switch Panel Features / Options

All-stainless brackets
2- and 3-switch configurations
Custom wire treatments: wire-protecting tubing, wire restraints (tie wraps), wire tags
Switch & wire color variations available (minimums may apply)
Sealed connections available: Weatherpak, Deutsch, ITT Sure Seal

The Buck Stops with CPI Liftgate Control Solutions

Given our durability and worldwide leadership in waterproof switching solutions, it’s likely that our switches will be the last you’ll ever need for your liftgate application. Give us a call today to discuss.

Original content posted on https://www.cpi-nj.com/blog/liftgate-engineering-for-work-trucks/

March 10, 2018

CPI Thermal Switches Are Heating Up

The vast majority of thermal switch applications we get have to do with keeping things from getting too hot. Just a few examples of this include:

Gally fire detection
Avionics Bay Over Temperature
Brake over temperature warnings
Hydraulic fluid temperature monitoring
Engine oil over temperature monitoring
Gun barrel temperature monitoring for heavy duty weapons.
APU temperature monitor…

The list continues but most of these applications are essentially safety systems where our high temperature thermal switch products are uniquely capable and reliable. They detect a high temperature and then close or open to activate a cooling system, an alarm, or a slowdown of the machinery to restore acceptable thermal limits.

The Navy’s Phalanx Gun Firing System

In an interesting twist on our normal thermal switch applications, one of our SnapStat series, flange mount thermal switches, is being used to heat things up!

The Phalanx system is part of a family of military defenses referred to as “Close-in Weapon Systems” (CIWS ) They are designed to engage anti-ship cruise missiles and fixed-wing aircraft at short range. Phalanx is the most heavily deployed CIWS with thousands of these guns mounted on US naval vessels and exported to allies around the world. Like other close-in weapon systems, Phalanx provides ships with a terminal defense against anti-ship missiles that have penetrated other fleet defenses. Phalanx is unique in that it combines search, detection, threat evaluation, acquisition, track, firing, target destruction, kill assessment and cease fire into a single, small deck footprint, mounting.

The electronics on Phalanx are complicated and actually work most reliably at a higher operating temperature. In this application our AD006-501 will trigger when ambient temperature in the electronics bay drops below 70F. This activation triggers heaters built into the gun to keep circuit boards in the bay from getting too cold!

In this application, our AD006, part of our SnapStat line of thermal switches (0 – 300F) switches almost 10 amps of resistive power. It is set to close-on-fall at 70F but our thermal switches are available in all varients (close on rise, open on fall, etc…)

CPI Thermal Switches for Military Applications

CPI is certainly a well seasoned supplier of military grade, thermal control components, having produced parts for the US military for over 70 years. We maintain these designs through the years, supporting the military’s upgrade and obsolescence programs, providing drop in replacements when older thermal switches from other manufactures cannot be produced any more.

Whether you’re trying to keep it hot or cold in your application. CPI’s thermal switches get the job done. Call our engineering team today!

https://www.cpi-nj.com

Original content posted on https://www.cpi-nj.com/blog/cpi-thermal-switches-are-heating-up/

December 26, 2017

When to use a Real Thermal Switch not a Sensor

When CPI started making thermal switches for the Military in the 40’s, there really wasn’t any other choice. Thermocouple based switches with variable set-points and various temperature ranges of operation were made using the thermocouple materials of the day, mostly copper, aluminum, and chrome. The concept of a thermocouple had been around for over 100 years but CPI switches of that time stood out because they provided reliable operation over an extended temperature range, in an environmentally hardened package suitable for battlefield conditions.

Temperature switch technology has evolved over the last 75 years however, and depending on what you’re trying to do, alternate thermal switching technologies abound. For instance, in applications where smaller temperature differences need to be measured with high accuracy (like from 0-100C at 0.01%), technologies like thermistors, temperature sensors tied to external control systems, or simple resistance thermometers may be more suitable and cost effective.

CPI Rod & Tube Thermal Switches

Still, traditional thermal switches have evolved too. The variety of types, and use of metal alloy’s has been informed by discovery, experimentation, and improvements in manufacturing processes. Today’s CPI thermal switches come in three basic types, covering a thermal range from 0 to 1750 degrees Celsius. And as always, CPI switches maintain their hardened design making them unique in the world for their electromechanical endurance, and their survivability.

Thermal Switch Applications

Perhaps one of the best ways to understand the applications that are better suited for thermal switches vs. sensors is to look at common applications for these switches.

Galley Temperature Sensors – Prevention of galley fires is critical on both Navy Ships and around any high temperature professional cooking stations. With flash points over 1000 degrees, these systems usually do not have a controller and so local switching to turn of gas supply or raise an alarm is appropriate.

Steel Manufacturing – Thermal Switches are used extensively in the steel and iron industries to monitor temperatures and chemistry throughout the steel making process. Disposable, immersible, type S thermocouples are regularly used in the electric arc furnace process to accurately measure the temperature of steel before tapping. The cooling curve of a small steel sample can be analyzed and used to estimate the carbon content of molten steel.

Engine Cooling Fan Control – Thermal Switches are commonly used to locally control cooling fans which prevent engine overheat on everything from generators to jet engines.

Gas Shut-Off – In systems using pilot lights, a thermal switch will often sense the presence of the pilot and shut off gas flow if the pilot should go out for any reason.

Oil Refining – Control of temperature in the oil refinery requires accurate and hardened thermal sensing for many fail-safe systems in the refining process.

Avionics Bay Over-Temp – In both commercial and military aircraft, ambient temperature in the avionics bay can reach well over 100 degrees C as components heat up, contributing to early system failure. Thermal switches are used here to economically activate cooling systems.

CPI Thermal Switches

Our three lines of thermal switches include the following.

Snapstat (0 – 300C)
Plugstat (0-600C)
Rod & Tube (0-1750C)

All switches are characterized by flexible mounting options, highly accurate and programmable set points, and hardened construction for extreme environments.

For more information on CPI thermal switches, please contact our engineering team today.

Original content posted on https://www.cpi-nj.com/blog/when-to-use-a-real-thermal-switch-not-a-sensor/

September 24, 2017

Monitoring Equipment Temperature is a SnapStat with CPI Switches

Almost every large commercial machine with an engine or motor of some sort has a system for monitoring temperature. Critical systems that are thermally controlled can be designed to shut down or throttle operation to prevent system failure or deliver cooling fluids that bring operation back into nominal ranges. In every case these switches must be trusted to prevent compromised safety situations which can cause damage to both man and machines.

Depending on the operating temperatures involved, CPI’s Thermal switch products are a go-to solution for hundreds of thermal monitoring applications around the world. Our line has evolved over 50 years to include three distinct thermal switch technologies that can accurately switch at precise setpoints from -20F to 1750F.

SnapStat Thermal Switch Applications for Harsh Environments

For operating conditions in the 0 to 300^o F degree range, CPI has a product line known as “SnapStat” which has been used in hundreds of harsh duty thermal monitoring environments.

Just some of these include:

Galley Fire Detection – our switch has been used to detect the conditions on a ship galley’s which could cause fire and activate warning lights or sirens.
Avionics equipment bay temperature Monitor – In this application our switch makes sure the overall temperature of the LRU bay stays in acceptable limits.
Food Processing Equipment – Items like Fryers and portable ovens have used our switches to monitor critical thermal limits in commercial cooking equipment.
Engine Oil Over Temperature – In equipment from Jets to Generators, CPI SnapStat thermal switches have been used to monitor oil temperature and activate safety systems prior to engine overheating.

A Versatile, Affordable solution to Over-Temperature Monitoring

The SnapStat switch is a close tolerance, bimetal type thermal switch made from all stainless steel and an option for a hermetically sealed design. The nature of the bimetal design makes it extremely resistant to high vibration, extremely accurate and the option for glass sealed, pre-soldered wiring of any length, makes it easy to integrate into your application.

Mounting options are equally flexible

We can even custom design a custom mounting for your application.

For over 50 years CPI has been providing robust thermal switching solutions into robust thermal applications. Give us a call today to discuss your design.

August 26, 2017

Dump Truck Safety System Design

The design of the modern work truck is moving forward at an amazing pace. With long haul trucks, the focus has been on collision avoidance systems and advanced controls for fuel economy, but dump truck builders have long had a different focus.

For Dump Trucks, it’s all about safety.

Historically, makers of class 8 dump trucks have not exactly been “early adopters” of technology, preferring instead to allow these advances to trickle down after many years of trial by fire on long haul trucks and other vehicles. More recently however, increased safety regulations, modularized construction methods and accelerated adoption rates for technology have conspired to put more and more intelligence in the “Dumb Dump Truck” than ever before. That means an increasingly connected vehicle, with improved fuel economy, and an ever increasing focus on safety systems.

Switches Used in Work Trucks Must be Robust

It turns out that CPI switches and sensors are critical components of safety systems on dump trucks, work trucks, and many construction vehicles owing mostly to their extremely durable, and watertight operational characteristics. CPI waterproof limit switches have an extremely small pendant switch style form factor and can be mounted in a wide variety of actuation mechanisms, allowing flexible placement in machines and vehicles. They can be sealed in either Neoprene or Santoprene making them fully waterproof and capable of extended temperature operation from -20 to 120 degrees F. And finally, the switches are capable of extremely high electromechanical endurance. CPI has qualified certain switch models to over 5 million cycles of operation.

Safety Systems In Dump Trucks and other Work Trucks

Here are just a few safety systems that have used CPI limit switches over the years along with the parts commonly used.

Dump Body Detection – Our E1092 simulated roller mechanism is mounted easily under the truck bed using one of our waterproof pendant switches like our B9112, NO switch. When the bed is raised, a circuit is completed, raising a visible (and potentially audible) alarm in the cab. This design is used for safety sensing in bucket trucks, loaders, and other vehicles that require mechanical feedback as to boom or bed position.

Cab Down Detection – This is a safety interlock switch function, which prevents the system from operating until the hood or cab is closed. While any of our E-series limit switches can be used, CPI actually makes a specific plunger style switch for this application called our J4 Plunger Switch. Originally developed for the military, this switch has an ultra-rugged design featuring a wiper seal and a plunger that can withstand 50 psi to overcome hardened-sand and ice buildup.

Neutral Safety Detection - J4 Ball or Plunger Switch

J4 Ball & Plunger Switches

Neutral Safety – One of the most common safety systems in commercial vehicles is neutral safety detection. In this application, various vehicle operations are prevented until the transmission is confirmed to be in neutral gear. Commonly chosen for this is our J4 ball switch, a hardened, small form factor, stainless steel ball switch designed with our patented seal exclusion system that actually forces contaminants out of the housing every time the ball is actuated. This waterproof switch design is so reliable and robust that it was used to detect the status of torpedo doors on navy submarines.

Back Up Alarm – Another common requirement of work trucks is the audible back-up alarm which sounds when the vehicle is moving in reverse. Our E1092 is a great example of a robust limit switch with a simulated lever actuator that is commonly used in this application. Completely made of high grade stainless steel it is truly waterproof, and completely customizable with almost countless mounting and actuator combinations available. This switch can be designed to meet operational standards for military use (B2 series) as well as heavy duty industrial applications (B3 thru B9 series). Parameters such as travel length, current rating, and electromechanical endurance are customizable. CPI has achieved endurance qualifications over 5 million cycles with this basic roller limit switch design.

Waterproof Safety Switches for Industrial Use

There are hundreds of specialized safety switch applications on dump trucks, work trucks and other industrial vehicles. Those that choose a CPI solution generally do so because they want the most reliable operation in the field that they can possibly have. When the safety of operators is on the line, why would you want anything else?

We have a vast amount of off-the-shelf options for our switches. And yet all our switches can be cost effectively customized for custom mounting and electrical parameters.

Call us today to discuss your safety switch system requirements with a product specialist. https://www.cpi-nj.com

Original content posted on https://www.cpi-nj.com/blog/dump-truck-safety-system-design/

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