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Posted by Electromechanical Team on 30 Aug 2017
Most people of a certain age have childhood memories of returning beverage bottles to their neighborhood store and getting back their deposit coins, which were usually just enough to invest in an extra piece of candy from the same retailer.
It’s a simple business model when viewed at the front end; but if you restrict your viewpoint of anything to only what happens in front of you, you’ll miss the sophisticated backend operations, which enable that simplicity.
Appreciating the intricacy of what makes any reverse supply chain work requires a logistics tour.
What separates the recirculation of beverage bottles from any other returnable asset is the sheer variety of shapes and sizes to be managed and the ability to do so with minimal loss and damage as the pace of business accelerates.
Let’s go back through the bottle return supply chain at the point we came in—the store.
When that retailer receives the bottles brought in by customers, it usually mixes bottle types in crates. Whatever business receives these crates from the retailer—whether a bottling company or a third party bottle management service provider—the receiver must be able to detect differences and sort accordingly.
Before automation, it would take 40-50 people to sort bottles by hand in some breweries.
Olaf Zeiss, Linear Actuator Product Manager, Electromechanical Division - Europe
Increasingly, beverage producers are leaving the task of detecting, sorting and returning those bottles to companies that invest in automated systems and training.
When a subcontractor is sorting bottles, they want to go as fast as possible because they get paid for every bottle. Zeiss
In Fuldabrück, Germany, Vision-Tec has made a business out of providing the necessary technology to bottling service providers to help them generate a profit from the returns process.
Vision-Tec offers automated modular material handling systems for crate and bottle detection, combining flexible multi-camera capabilities with sortation. This technology uses vertical and oblique image capture as well as ultraviolet light to detect various shapes of bottles and labels. Even a bottle’s luminescence can be detected--and with ultrasound, bottle height can be checked—with or without a cap.
This is sophisticated technology, calling for machine intelligence to remove counterfeit bottles and then refill or complete boxes with like bottles.
We were pleased when Vision-Tec chose to work with Parker Hannifin to supply multiple components for their automated bottle handling and sortation systems.
For instance, our linear actuators provide the higher velocity and acceleration required to meet the performance requirements of beverage producers and bottlers. Further, our actuators withstand the fluctuating temperatures of European summers and winters and the corrosive environments of bottling plants.
In summertime these breweries and bottlers work 24 hours a day. These are wet environments, where the equipment is cleaned regularly and the plant doors are normally open because bottles are always coming in and going out. The actuators must withstand these temperature swings.
That ruggedness extends to the motors and gears used in Parker’s drive combinations, which offer IP65 compliance (resistance to water and dust).
Vision-Tec’s sorting robots must be equally robust—not to mention scalable and expandable. Sort stations are equipped with two grab arms each, taking the wrong bottles out of the crates as they are fed into the line, and then filling in the right ones in continuous motion operation. By setting up intermediate storage/buffers, travel paths for the grab arms can be substantially reduced. Depending on the stage of extension, up to 1,200 boxes per hour can be sorted.
In addition to their complex optical systems and control technology, Vision-Tec uses Parker Hannifin HPLA linear axes for controlling the mechanical longitudinal movements (in the running direction) of the sorting modules. In conjunction with intelligent Parker compax3 servo controllers, with their EtherCAT communication interface, these features are designed not only to meet the requirements of beverage bottlers, but of textile engineering firms, process engineering companies, logistics service providers, warehouses and machine tool manufacturers, as well.
Parker’s complete drive packages contribute significantly to the high performance and reliability of our systems. Also significant [are] their support for the sizing process and configuration process of the drive systems, and the solution’s rapid availability.
Knut Oppermann, Technical Manager, Vision-Tec
Vision-Tec is planning five to ten more bottling lines by the end of the year for other beverage companies, and Parker will help it customize system requirements to those different needs.
While bottle return processing will never be as simple as the front end transaction, with these automated systems, it may seem so. Just take a look at the video.
Read more customer success stories here
Meet our engineers at PackExpo in Chicago September 25 - 27 and test out our latest solutions in the IIoT, and packaging and processing manufacturing. Visit us at booth S-7965 to ask questions of the team related to this content or any of our products. Not attending the show? Learn more about our processing and packaging solutions here.
Contributed by Rochus Bindner, marketing communications manager, Electromechanical Division Europe.
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With its high power density and flexible mounting capabilities, permanent magnet direct drive servo motors like the Parker PM-DD series have a proven track record in many manufacturing applications. Let's take a look at five successes spanning various industries.
As the world's communications infrastructure continues to grow and evolve, the demand for fiber optic cable has been increasing. With Parker distributor Cross Automation in Charlotte NC, we were able to provide PM-DD motors for a vertical lathe, used to dispense glass for fiber optic wiring. The combination of smooth low-speed operation, compactness, and the ability to mount directly to the rotating shaft made the PM-DD a winner over standard servo motors.
Machine tools demand accuracy, and in the second case study, the task at hand was to repeatedly index a table that was three feet in diameter. With displacement occurring 1.5 feet (457 mm) away from the motor centerline, its high resolution (20 bit) absolute encoder was critical to the application. Thanks to the PM-DD's high load carry bearings, (1500 N in this case) where previously a conventional servo motor and worm gear solution was used, the PM-DD proved to do the job while eliminating the worm gear. The drive train was simplified and ongoing maintenance associated with the mechanical gearing was eliminated. This solution was sold by Faber Associates, Parker distributor based in Clifton NJ.
Automotive assembly is a rigorous application with hundreds of interdependent operations, all of which must function reliably, at the risk of costly downtime. A rotary table was used in the operation of adjusting vehicle headlights. Simplicity and high positioning resolution were the main factors leading to the adoption of the PM-DD in an application solved by Parker distributor Reco-Wesco from Indianapolis. Being able to mount the motor directly to the table eliminated the need for multiple mechanical components that would have required maintenance and been a potential failure mode.
Automotive industry testing applications often duplicate real-life scenarios that the finished vehicles will be exposed to, but must take into account the worst-case situations. In this case, the PM-DD motor was used for an electronics test bench. Part of a multi-axis assembly, the test bench would simulate the rough vehicle road conditions, including a rollover, that the electronics might be subjected to. PM-DD was preferred over a standard servo motor due to its smooth, slow speed, operation, good bearing support and high torque. This solution was sold by Parker distributor RSA of Fond du Lac WI.
The fifth and final application was in the life sciences field. A PM-DD motor was used for an indexing table that carried five stations to support the assembly of medical devices. The first station was to load the part, second applied adhesive, third was for UV curing of the adhesive, fourth was inspection and fifth was where the part was unloaded. In this case, the PM-DD replaced a pneumatic indexing table. Key to its success was a smooth start and stop operation versus the previous pneumatic solution. Also, the PM-DD with Parker P-Series Drive allowed for a variety of indexing locations to be programmed providing more flexibility than a more traditional rotary indexing table. This solution was provided by Automation Incorporated, a Parker distributor out of Minneapolis MN.
Learn more about the PM-DD by visiting our Precision Direct Drive Rotary Servo Motor Series Product webpage to buy or download a Parker P series
Direct Drive Rotary Motors catalog.
Article contributed by Jeff Nazzaro, gearhead and motor product manager, Electromechanical & Drives Division, Parker Hannifin Corporation.
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The basic theory of operation for brushless servo motors revolves around the principles of magnetism where like poles repel and opposite poles attract. There are two magnetic sources found within a servo motor: Permanent magnets that are typically located on the rotor of the motor, and the stationary electromagnet that surrounds the rotor. The electromagnet is called either the stator or motor winding and is made up of steel plates called laminations, that are bonded together. The steel plates typically have “teeth” that allow copper wire to be wound around them.
Going back to the principles of magnetism, when a conductor like copper wire is formed into a coil, and the conductor is energized so that current flows through it, a magnetic field is created.
This magnetic field created by current passing through the conductor will have a north pole and a south pole. With magnetic poles located on the stator (when energized) and on the permanent magnets of the rotor, how do you create a state of opposite poles attracting and like poles repelling?
The key is to reverse the current going through the electromagnet. When current flows through a conducting coil in one direction, north and south poles are created.
When the direction of the current is changed. the poles are flipped so what was a north pole is now a south pole and vice versa. Figure 1 provides a basic illustration of how this works. In figure 2, the image on the left shows a condition where the poles of the rotor magnets are being attracted to the opposite poles of the stator. The rotor poles, which are attached to the motor shaft, will rotate until they are aligned with the opposite poles of the stator. If all stayed the same the rotor would then remain stationary.
The image on the right in figure 2 shows how the stator poles have flipped. This would happen every time the rotor pole caught up with the opposite stator pole by reversing the current flow through that particular stator location. The continual flipping of stator poles creates a condition where the permanent magnet poles of the rotor are always “chasing” their stator opposites which results in the continuous rotation of the rotor/motor shaft.
The flipping of the stator poles is known as commutation. The formal definition of commutation is “The action of steering currents to the proper motor phases so as to produce optimum motor torque and motor shaft rotation”. How are the currents steered at the correct time to maintain shaft rotation?
The steering is done by the inverter or drive that is powering the motor. When a drive is being used with a particular motor an offset angle is identified in the drive software along with other things like motor inductance, resistance, and other parameters. The feedback device that is used on the motor (encoder, resolver, etc..) provides the position of the rotor shaft/magnetic pole to the drive.
When the magnetic pole position of the rotor matches the offset angle, the drive will reverse the current going through the stator coil thereby changing the stator pole from north to south and from south to north as shown in Figure 2. From this you can see that letting the poles align will stop the motor shaft rotation, or changing the sequence will get the shaft spinning in one direction vs. the other, and changing them quickly allows for high speed rotation, or just the opposite for slow shaft rotation. Learn more about servo motors here.
Other articles related to servo motors include:
What You Should Know About Frameless Motors
Struggling to Select the Right Encoder Feedback? Read this.
Choosing the Right Rotary Servo Motor Feedback Device - Part 2