machinery

• CONTROLS - Most machines have number of sensors to monitor and control operations. These sensors perform avariety of functions including detection, verification, inspection and more
• SWITCHES - SNAP-Action switches AKA “MICROSWITCH” used to provide on-off control in simple applications.They are available in variety of standard sizes. Their principle disadvantage is physical contact.
• PHOTOELECTRIC SENSORS - Also known as photo eyes or photo sensors. Some machines may have dozen. Common applicationinclude sensing, absence or proximity. Special sensors are available only sensing specific color.
• 3 components of a sensor -

  light emitter

  receiver

  control electronics
• Opposed beam configuration - interruption of the beam the sensor triggers.
• Retroreflective system - light source and sensor are in same housing, reflector is placed on theopposite side and when objects pass the absence of the reflection will trigger the sensor.
• Convergent beam system - similar to retroreflective system only that the reflector is the packageitself. Disadvantage is color. Conveyor color and bottle color should not be the same.
• Fiber-optic cables are made of strands of optically pure glass fibers. They allow transmission of lightwith little degradation. In an opposed beam photo sensor arrangement
• CAPACITANCE PROXIMITY SENSOR - Frequency of checking the proximity of the product, package or component is much needed during fastproduction. One technique is the use of proximity sensor. The distance at which the sensor triggers canusually be adjusted by gain or sensitivity adjustment in the sensor.
• PROGRAMMABLE LOGIC CONTROLLERS (PLC) - is a specialized type of computer used to control machine functions. This allows the operator toinitiate the change by selecting a menu on the machine control panel. The advantage include sizeand reliability
• PROGRAMMABLE AUTOMATION CONTROLLERS (PAC) - can run programs such as spreadsheets, word processors,graphics and video. A word of caution on security: anytime a machine is connected to any networkoutside of the machine itself, it can be susceptible to outside tampering
• HUMAN / MACHINE INTERFACE (HMI) - also known as control panel. This is where human operator interacts with machine.Improvement over the years have been wide from manual to touchscreen display.
• Direct Current (DC) Motor – most common motor type used in the packaging machinery due to itsease of being controlled.
• Voltage controller is used to control input from 120-220volts down to 90 volts.
• Alternating Current (AC) Motor - Speed determined by the motor design and the frequency of theincoming power.
• Reducing the voltage to an AC motor will normally not slow it but may overload andpossibly damage it.
• Variable Frequency Drive (VFD) - allows speed variation without changing the voltage orfrequency. It uses electronic circuitry to change the incoming AC waveform into DC then back to AC at a different frequency. The VFD is typically mounted close to the motor.
• Servo Motor - are a special class of motors designed for precise motion control. They are controlled via software to perform desired functions. It may even reverse for a portion of a revolution to provide suck back of the product so it doesn't drip after filling
• Rotary servo motors - They can rotate a precise amount in either direction, which allows themto be used to control back and forth motions
• Linear servo motors - are controlled on the same electrical principles as rotary. Instead ofrotating, the armature shaft moves linearly in and out of the coil. This can be used to drivereciprocating mechanisms, such as piston pumps, or to replace air cylinders
• Advantage of Using Servo Motor -

  noise

  jams

  ease of changeover

  simplicity

  tightness

  force measurement
• Hydraulic motors - are not common in packaging machinery but may be used in some largersystems.
• pneumatic motors - powered by compressed air
• When working with flammable or explosive materials, avoid the use of electricity wherever possible.One way to do this is via pneumatic motors powered by compressed air.
• Belts can transmit large andsmall amounts of power over short or long distances. Varying the relative size of driving vs drivenpulleys can provide the required increase or decrease in speed at the driven component.
• Chains - are a common alternative to belts. These will usually be roller chains, similar to bicycle chainsbut usually heavier duty and larger.
• A disadvantage ofchains is that they must be lubricated. Failure to provide regular lubrication will result in prematurewear and failure of both chain and sprockets
• Cams - are frequently used to convert the normal rotation of a motor or shaft into a reciprocating linearmotion.
• The line shaft is a heavy shaft running the length of the machine and driven by the main motor.
• Intermittent-motion - machines require that motive power be provided intermittently to the machine.This may be accomplished by stopping and starting the motor but this will usually not bring themachine to rest in a consistent position.
• Packaging line - a group of integrated special-purpose machine that combine product and package inputs and produce a product.
• Input - Specific product and package required for package assembly.
• Design speed - theoretical capacity under perfect running conditions.
• Capacity - upper sustainable limit of quality packages passing a point just above warehousing.
• Run Speed - Instantaneous operating rate at a point in time.
• Output - The exact quantity of quality product passing a point just before warehouse or shipping in a given time.
• Efficiency - Ratio of output over input
• Bpm / cpm- Bottles per minute / Containers per minute
• BUFFER - Generally used to isolate the least efficient station on the line.
• Changeover - a change from one system or situation to another.