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Intech Power-Core Thermoplastics Engineering Blog

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Anti backlash gear design at the heart of clear tomography imaging

  
  

 

Special gear design is at the heart of clear image in multi-axis tomography device.

For the rotational machines used to gather dental X-ray images, motion chatter can produce a fuzzy image, which is not suitable for diagnostic purposes.

Panoramic radiography is a branch of rotational tomography where the creation of images are through the movement of a source and receptor in such a way as to cause the foreground and background structures to blur, leaving a defined focal trough.

As a panoramic radiographic device, the Vantage Panoramic X-ray System, designed and manufactured by Progeny, Lincolnshire, IL, incorporates a DC X-ray source, CCD digital receptor, distributed processing circuitry, and an LCD touchscreen control panel for ease of use. What makes the Vantage system unique is that it is adjustable to the patient’s height via a motorized, 3-speed, telescoping column. The use of multiple lasers is to locate the patient and configure the device to the patient’s morphology. In addition, a workstation coordinates the individual processors.

The system incorporates an overhead, swing arm (lateral Y-axis) that supports a C-arm, which is the rotating member that moves around the patient’s head. The C-arm includes a tube-head, which produces the X-ray beam, and a removable CCD sensor, which is the digital image receptor. If this arm does not operate smoothly, a distorted image results.

The swing arm pivots on bearings located in the mounting casting fastened at the top of the column. Producing its motion is a ball screw drive, one end of which connects to the mounting casting and the other end to the swing arm. A step motor mounts at the column end. Both mechanical connections of the drive assembly are through ball bearing assemblies.

Suspension of the C-arm is on a pair of bearings mounted to the underside of the X-axis translation plate. The C-arm casting incorporates a 10" ID internal tooth ring gear that meshes with a pinion gear on a step motor mounted on the stationary X-axis translation plate. The motor is spring-mounted to maintain positive mesh and to minimize slop. The internal ring gear and pinion are sized and shaped to engage on the inside surface of the C-arm. With activation of the motor, the stationary pinion engages the teeth in the internal ring gear causing rotation of the C-arm.

The engineering team at Progeny worked with Intech to help design the C-arm casting and its interface with the gear drive for the C-arm’s rotation. Design of the company’s Power-Core products is specifically to reduce noise and vibration and run without lubrication, an important factor (a must) for medical equipment designers. Intech components are far lighter in weight than metal parts and offer longer life (less wear) and lower maintenance costs. Intech engineers used a proprietary gear load/life calculation to verify that the gears designed into the dimensionally restricted place would last at least 8,000 hours of operation or about 15 years in field use.

The challenge was to design a backlash free gear to produce a steady rotational movement of the image producing components. There was no room to employ the traditional split gear design. To eliminate backlash, installation of a spring, on slight angle relative to the axis connecting the gear centers attached to the pinion, pulls the pinion toward the 10" ID internal ring gear. The spring arrangement did eliminate the backlash, but caused the gear teeth to bottom out, resulting in chatter. The chatter registered on the X-ray image.

The precision gearing for the Vantage Panoramic X-ray System uses Intech’s Power-Core nylon materials for reduced chatter, resulting in clearer images from the system.

Drawing on its expertise in gear design, Intech engineers designed and precision-machined the pinion and the internal gear to incorporate a special contact surface, which allowed the components to control the center-to-center distance between the inner tooth gear and the motor pinion. Adding the center-to-center distance management element presented a method for precise gear positioning in the mesh, and drastically reduced system vibration generated by the spring force and the resulting bottoming out of the gear teeth in the earlier design.

This configuration provides precise control over gear mesh vibration and backlash, resulting in high image quality in both a clockwise and counterclockwise rotation of the C-arm. It also adds a robust design element, which helps to increase product life so that image quality does not degrade with component wear and tear. With no fuzzy imaging due to chatter, dentists can make better diagnosis and provide better service to their customers.

Shown is the Vantage Panoramic X-ray system with the C-Arm that holds the lasers as well as the removable CCD receptor..

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This article was featured in Today's Medical Developments magazine and can be viewed at http://www.onlinetmd.com/TMD-0912-motion.aspx

Cam Followers for RT Light Testers in Can Making Production Line

  
  

In a high speed can making production line, light inspection is required to find pin holes and split flanges after the necking process. Once cans have been coated and sealed, these finished cans are tested for leaks using a light tester, which can detect holes 0.002” wide, smaller than a human hair, and also spot cracked flanges as small as 0.015”.

When Intech iCamFollowers® are installed on the light tester ram they ensure that 3,000+ inspections can be performed per minute, more than sufficient to keep up with the high speed can production line and offer several important benefits.

After installation, the lubrication lines originally used to grease the metal cam followers can be disconnected, cutting down on periodic maintenance and possible contamination of the can. Another important benefit is the fact that the cam propelling the ram back and forth is now protected from wear by the IPC tire.

Fitted with precision ball bearings the Intech iCamFollowers® are easy rolling and the plastic tire does absorb shock and vibration for overall smoother performance.

The Intech iCamFollowers® have also been running successfully for many years in the necking operation on Belvac neckers, both on rams made by Intech, the light weight, self-lubricating square ram, as well as on the original Belvac rams.Light tester and cam followers

Low inertia Power-Core spur gear increases caplet machine output

  
  

One of our customers, who manufactures packaging machines for the pharmaceutical industry to produce caplets, sought to improve its competitive standing by eliminating the need to lubricate the 16” cast iron main drive gear and replacing it with a lubrication free Intech Power-Core™ gear.

Upon installation of the lubrication free Intech gear, the engineers ramped up the output to 600 caplets per minute (cpm), the industry standard, and discovered that there was no vibration previously experienced with the heavy cast iron gear. Encouraged by the performance of the low inertia Intech Power-Core™ gear, they increased the output to 700…800…, all the way to 1200 cpm. Even at this speed the machine was running smoothly and without vibration.

This was in contrast with all the previous experience using the cast iron gear which reached its critical RPM around 700 RPM, at which point the machine shook violently, and the reason why the output had been established at 600 cpm.

The customer settled on an output of 800 caplets/min as a standard for the company’s brand, a 25% increase over competitive machines. The first reward came shortly after introduction of the new machine. A company producing caplets used in automotive air bags sought to increase its capacity by 2400 caplets/min. Our customer was able to satisfy that demand with three machines that don’t require lubrication, where all its competitors quoted four machines that required constant lubrication and frequent shut down for maintenance.

Low inertia often becomes the dominant, albeit unexpected benefit of changing to self-lubricating Power-Core™ gears. The main drive in the DaVinci surgical robot is another good example.

Low Inertia Spur Gear Installed in Caplet Machine

Guide rollers hold camera steady on gantry suspended over race track

  
  
The average speed of a NASCAR car varies from one race track to another, it is calculated based on the winner’s lap speed through the entire race. The fastest track on the circuit is the Talladega Superspeedway, where the recorded average speed is about 188 miles per hour (303 kilometers per hour).

In order to capture video images of the race cars as they streak along the track at these phenomenal speeds, a camera needs to resist the buffeting and turbulence generated by the passing cars. Doggicam Systems adapted its patented movie camera system to create the Super Slide, a high speed light weight super-rigid rail system which allows the camera to be moved with precision and tremendous speed and acceleration.

Doggicam Super Slide with Power-Core rollers

The Doggicam Super Slide runs back and forth at high speed in a rail across a suspended gantry over the NASCAR race track


A key component, that allows the Doggicam Systems Super Slide to deliver high speed precision and move safely within inches of the subject, are the Intech Power-Core™ rollers that we supply. These rollers ensure a smooth vibration free rolling transit of the camera system along the rail, with minimum resistance, allowing it to accelerate from 0-24’ / second in just one second and reach a top speed of 25’ per / second.


Doggicam Systems Super Slide Design with Intech Power-Core rollersIntech Power-Core rollers are a key component of the Doggicam Systems Super Slide


Intech Power-Core™ rollers eliminate both the need to lubricate and rail wear and offer an ideal long-lasting solution in the demanding conditions, from extreme heat, vibration, torrential rain, to freezing temperatures, to which the Doggicam Super Slide is exposed.

Intech guide rollers are also used in mechanisms that move cameras in TV studios or on film sets, where smooth, vibration free and quiet camera operation is paramount.

Are steel cam followers overrated for use in packaging machines?

  
  

“Metal cam followers are overrated” said one packaging engineer in a recent conversation when asked why he opted for Intech’s iCamFollowers®. Here is why we agree with his opinion:

It seems that a large number of cam followers, metal ones that is, are used for their convenience not their load carrying capacity. Tap out a hole and you are ready to install a cam follower, providing designers with an instant “wheel” that allows parts of machines to move back and forth. The cam follower was not selected for its load capacity, rather enabling a movement required by the process.

There is a price to pay for this convenience. The rail on which the metal cam follower runs has to be periodically lubricated, as does the needle bearing in the cam follower. Lubrication, especially surface lubrication can contaminate packages and is a constant burden on maintenance. If you do not lubricate, the rail will wear and if you apply too much grease, there is a good chance that some of it will end up on the product. Over greasing of the cam followers’ needle bearing may cause the cam follower to stop rotating and instead be “dragged” along, causing a flat spot on the outer racer and excessive wear on the rail. This can happen when the radial load is relatively light for the heavy duty cam follower or if the radial load drops to zero during the operating cycle, for example on cams where the cam followers are used to exert force in only a portion of 360° rotation of the cam.

To replace a damaged cam follower is relatively inexpensive, while replacing a fixed rail or a cam can cost days of down time. Grease contaminated products carry their own cost.

Intech’s iCamFollowers® eliminate both the need to lubricate and rail wear and offer a cost effective alternative to metal cam followers in most packaging applications. The easy rolling, precision ball bearings thermally installed in the plastic tire offer very little rolling resistance and are lubricated for life. This ensures a smooth rolling motion even in light duty applications. Not to worry, the iCams will also carry heavy loads. Intech engineers developed a load / life expectancy calculation and the resulting load data allows engineers to select a cam follower suitable for the load in their application. So for example the IPC – 1.500 iCam will carry 300 lbs for 100 million cycles (1 cycle = one 360° rotation) without developing a flat or wearing out. Most importantly, it will not wear out the rail, steel or aluminum.

In addition to being able to carry high loads, the plastic tire will absorb shock & vibration, reduce rolling resistance, cut noise by up to 10 dB, and will work in sub-zero temperatures. For wash down applications the cam follower is delivered with stainless steel shafts and bearings. All this without lubrication or rail wear.

Intech’s iCamFollowers® also open up the way to more cost effective designs. Since iCamFollowers do not wear out the rails, designers can run the iCams directly on aluminum frames, without having to use steel or stainless steel strips to prevent rail wear. To further simplify the design central lubrication systems’ need for cam follower lubrication can be eliminated.

Are metal cam followers in your application overrated? Intech engineers can help you to determine that.

Intech iCamFollowers

Intech’s long-wearing, lubrication-free, heavy duty iCamFollowers® replace conventional metal cam followers

Combating vibration, shaft bearings are only as good as their grease

  
  

Intech Power-Core™ guide rollers and iCamFollowers™ absorb shock and vibration and their life is typically calculated for 100 million cycles, a performance relying in part on longevity of the roller bearings installed inside the plastic tires. Tests have found that degraded lubrication is the leading cause of bearing failure.

In harsh environments with high shock load frequency, combined with high humidity, some grease types can liquefy, then this will cause leakage from the bearing seals or can produce an added churning-friction effect on the bearing. As a result, in high speed applications, the operating temperatures will rise significantly, compounding the breakdown of the grease properties and resulting in premature bearing failure.

We have identified a new type of lubricant to improve our rollers resistance to shock and vibration by providing lubrication to the bearing when operating under extreme conditions. The grease, NLGI No. 2, has shown a consistent mechanical stability and less churning or deterioration than other lubricants.

We have been able to apply this newly acquired knowledge in a case of premature bearing failure in guide rollers used in a train sliding door in Florida. Exposure to high frequency vibration and high humidity caused a bearing failure while the plastic tire remained intact. By regreasing the guide roller bearings with the NLGI No. 2 grease, we have been able to better match the expected life of both the plastic tire and the bearings.

Intech Corporation is constantly striving to improve its products and certainly the discovery of this grease’s properties helps our customers extend the life of our rollers and bearings in shock and vibration applications.

Cam follower for packaging application 

 

 

 

 

 

 

 

 

Cam follower for packaging application

 

Concave, v-shaped, flat tire rollers

Concave, v-shaped, flat tire rollers

 Intech Rollers for High Security Door

Intech Rollers for High Security Door

High speed rotating face cams machined from Power-Core™ outlast steel

  
  

Exact steerage requires dimensionally stable cam tracks with narrow tolerances. Our cams are precision machined from solid blocks of cast Intech Power-Core™ material, offering a longer lasting solution than stainless steel.

In high speed machines Intech Power-Core™ cams exhibit damping behavior which leads to reduced stress peaks. Additionally the high performance plastic cam offers exceptional resistance to wear with limited or no lubrication, which is critical to avoid contamination.

The face cam converts circular motion to linear motion or vice versa, typically it is a disc with a groove cut in its face, in which a cam follower travels. The attached image shows such a cam used in a tableting machine.

In this case the customer required self-lubricating material performance and had experienced constant stress problems using cams machined from plastic materials with low levels of crystallinity, such as Delrin®. However they found that Power-Core™ material, with higher crystallinity levels, can be used to produce a more stable cam that does not suffer stress peaks.

Industries in which our cams have been used include packaging, food processing, printing, as well as stitching machines and other general engineering applications.

In high speed machines Intech Power-Core™ cams exhibit damping behavior which leads to reduced stress peaks. Additionally the high performance plastic cam offers exceptional resistance to wear with limited or no lubrication, which is critical to avoid contamination.


The face cam converts circular motion to linear motion or vice versa, typically it is a disc with a groove cut in its face, in which a cam follower travels. The attached image shows such a cam used in a tableting machine.

In this case the customer required self-lubricating material performance and had experienced constant stress problems using cams machined from plastic materials with low levels of crystallinity, such as Delrin®. However they found that Power-Core™ material, with higher crystallinity levels, can be used to produce a more stable cam that does not suffer stress peaks.

Industries in which our cams have been used include packaging, food processing, printing, as well as stitching machines and other general engineering applications.

Face Cam for Tableting Mach resized 600

Face Cam precision machined from cast Intech Power-Core™ material reduces inertia, absorb shock and vibration.

Composite Worm Gears Extend Wear Life in Tough Applications

  
  

Intech engineers are frequently asked for help to determine worm gear size, design parameters and to make wear-life projections using our proprietary gear calculations. As a result of these calculations, Intech Power-Core™ composite worm gears are chosen to replace industry-standard bronze gears in demanding operations to increase transmission efficiency with quieter, longer-wearing performance.

Intech Power-Core Worm Gears


Intech Power-Core Worm Gears


Power-Core material does not require special grade oil or frequent oil changes and the composite material does not generate abrasive particles which become suspended in the oil as a contaminant that contributes to wear. The tough, self-lubricating properties of the composite gear material enable Intech Power-Core worm drives to consistently outlast conventional bronze worm gears.

We completed a 1,000 hour test that compared gear performance between the Intech Power-Core gear and a case-hardened ground steel worm gear, and the results confirmed the capacity of Power-Core material to absorb shock load and vibrations. Test data showed an average noise reduction of 6 dB, with up to an 8% increase in gear transmission efficiency and no wear was detected on the 6.5 PD Power-Core worm gear.

In applications such as conveyors for glass washing or light load semi-conductor manufacturing machinery, the Intech Power-Core worm gears run with only light grease lubrication, or completely dry. Even in high torque applications that result in friction, the self-lubricating Power-Core worm gear can run for extended periods without lubrication.

The mating worm shaft can be made of conventional materials utilizing standard manufacturing methods. The low-maintenance Power-Core composite worm gears use readily available machine oil to lubricate the gear box, instead of more expensive specialized synthetic oil that is usually recommended for bronze worm gears.

Medical Latex Dipping Device for Easy Cleaning with Proprietary Gear Design

  
  
Power-Core™ gears have been used to upgrade the design of a latex dipping gear cassette assembly in a unique arrangement that replaces standard gears in order to meet critical performance and cleaning challenges.

The original gear box design resembled a tightly fitting cassette made with standard off-the-shelf gears. Unfortunately, as the latex material was being processed, the gears reacted with the latex material and expanded in size until the ceased turning. Cleaning required a complete disassembly of the cassette, followed by awkward and time-consuming hand scrubbing of individual components to yield less-than-satisfactory results.

In addition to requiring an easier cleaning process, the medical device manufacturer wanted longer wear-life and improved performance from the gears. Frequent cleaning and premature gear failure caused by gear swelling resulted in wear stress that resulted in system downtime and replacement on average every few months.

As part of a failure analysis, Intech provided an engineering design review that included a custom gear life calculation. Our engineering team recommended a system design modification to address performance uptime, improve wear life, and to create a user-friendly non-hazardous cleaning process.

open sandwich design allows easy cleaningThe gear box modification design features custom Intech Power-Core™ gears with a larger pitch diameter, wider face width, and an integral stainless steel shaft that extends on each side of the gear and rotates directly within the load bearing cover plates. The open sandwich design, which can be seen in this image, allows for easy cleaning.

Compared to the previously used injection molded gears which vary in size due to internal stresses and moisture absorption, the precision machined Intech Power-Core™ gears provide consistent, smooth-running operation at reduced torque. Uniform Power-Core material will not distort or change size, so individual gears can be interchanged easily without matching pre-existing gears for a uniform fit, whereas injection molded gears had to be matched to other gears in order to function.

Intech Power-Core™ gears are machined from an inert, stress-free non-hygroscopic material with integral stainless steel shaft that offers outstanding performance where corrosion, abrasion, noise, lubrication, vibration, shock, and moisture create hostile operating environments.
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