Resources: Glossary

Accumulation Conveyor: Any conveyor designed to permit accumulation of packages, objects, or carriers. May be roller, live roller, roller slat, belt, vibrating, power-and-free, or tow conveyors. See Minimum pressure accumulation conveyor and Zero pressure accumulation conveyor.

Automated Storage/Retrieval Systems (AS/RS): A combination of equipment and controls which handles, stores, and retrieves materials with precision, accuracy, and speed under a defined degree of automation.

Ball Table: A group of ball transfers over which flat surfaced objects may be moved in any direction.

Ball Transfer: A device in which a larger ball is mounted and retained on a hemispherical face of smaller balls.

Bearing: A machine part in or on which a journal, shaft, axle, pin, or other part rotates, oscillates, or slides.

Bed: That part of a conveyor upon which the load rests or slides while being conveyed.

Belt Conveyor: An endless fabric, rubber, plastic, leather, or metal belt operating over suitable drive, tail end and bend terminals and over belt idlers or slider bed for handling bulk materials, packages, or objects placed directly upon the belt.

Bin: A container for storing material.

Brake Roller: Air or mechanically operated brakes used underneath roller conveyor to slow down or stop packages being conveyed.

Bushing: (1) In machinery, a removable liner fixed in a bore to improve the bearing surface; (2) In chain, a renewable liner fixed in the barrel of a link, or center link, to provide an improved bearing surface; (3) in chain, a hollow cylinder used to space the sidebars and provide a bearing surface for the chain pin, and on which the rollers may or may not be mounted.

Capacity: The number of pieces of a defined size, volume of material, that can be handled by a conveyor in a unit of time.

Ceiling Hangar: A support fastened from an overhead frame work to position and carry loads.

Chain Conveyor: Any type of conveyor in which one or more chains act as the conveying element.

Chain Drive: A power transmission device employing a drive chain and sprockets.

Chain Driven Live Roller Conveyor: See Live Roller Conveyor.

Chain Tension: The actual pull existing at any point in a conveyor chain.

Cleated Belt: A belt having raised sections spaced uniformly to stabilize flow of material.

Clutch: A device to permit engagement or disengagement of equipment while in motion or at rest.

Coefficient of Friction: A numerical expression of the ratio between the force of contact existing between two surfaces and the resistant force tending to oppose the motion of one with respect to the other. The coefficient of friction is used in determining the power necessary to drive a machine; to determine the slope angles used in hoppers, bins, chutes, and bunkers; or to determine the maximum angle of inclination for a conveyor.

Control Enclosure: The type of construction of the housing or case which encloses a control component or assembly of components. The common types of enclosures are designated by NEMA.

Conveyor: A horizontal, inclined, or vertical device for moving or transporting bulk materials, packages or objects in a path predetermined by the design of the device and having points of loading and discharge fixed, or selective; included are skip hoists and vertical reciprocating and inclined reciprocating conveyors. Typical exceptions are those devices known as industrial trucks, tractors and trailers, tiering machines (truck type), cranes, hoists, monorail cranes, power and hand shovels, power scoops, bucket drag lines, platform elevators or conveyors designed to carry passengers or the elevator operator, and highway or rail vehicles.

Conveyor Belt: A belt used to carry materials and transmit the power required to move the load being conveyed.

Conveyor Width: (1) In unit handling, the dimension inside to inside of frame rails; (2) In belt conveyors for bulk materials, the width of the belt; (3) In vibrating conveyors, distance between side walls; (4) In slat conveyors, the length of the slat.

Countershaft: An intermediate or secondary shaft between the drive shaft of a conveyor and the source of power.

Cross Ties: Structural members which maintain frame rail spacing on unit handling conveyors.

Crown Lace Pulley: A pulley with greater diameter at the center than at the ends.

Curved Belt Conveyor: Unit load belt conveyor usually operating horizontally through various angle turns, usually 30, 45, 60, 90, or 180 degrees.

Dead Loads: The combined weight of the conveyor elements and supports.

Decline Conveyor: A conveyor transporting down a slope.

Degree of Decline: Angle of slope (in degrees that a conveyor is installed.

Differential Curve: A curved section of roller conveyor having a conveying surface of two or more concentric rows of rollers. Also referred to as a Split Roller Design.

Discharge End: Location at which objects are removed from the conveyor.

Double Pitch Chain: A roller chain using the same joint members as standard pitch chain and having the same dimensions except for the pitch which is twice standard.

Drag Chain Conveyor: A type of conveyor having one or more endless chains which drag bulk materials through a trough.

Drive: An assembly of the necessary structural, mechanical and electrical parts which provide the motive power for a conveyor.

Drive Belt: A belt which is used to transmit power or motion from one part to another.

Drive Chain: A chain used to transmit power.

Drive Shaft: (1) A main driving shaft on a which conveyor sprockets, gears, or pulleys are mounted. This shaft is connected to the drive unit through a coupling, sprocket, gear, or other form of mechanical power transmission; (2) A shaft used to support the end of a conveyor screw in a trough end and as a driving connection between a conveyor screw and the power transmitting medium.

Driven Roller: Any carrying roller driven by belting, chain or other propelling medium.

Emergency Pull Cord: Vinyl coated cord that runs along the side of the conveyor that can be pulled at any time to stop the conveyor. Used with an Emergency Stop Switch.

Emergency Stop Switch: Electrical device used to stop the conveyor in an emergency.

Extendible Conveyor: Roller or wheel conveyor that may be lengthened or shortened within limits to suit operating needs. Standard extended lengths are 20 ft., 30 ft., and 40 ft.

Escapement: In a gravity or power operated package conveyor, a device to permit the release of packages one at a time on demand.

Explosion-Proof: Equipment designed in accordance with existing codes and standards such that it will operate in a specified hazardous environment without causing an explosion. For further information, contact the National Electrical Manufacturers Association (NEMA).

Feeder: A conveyor adapted to control the rate of delivery of packages or objects.

Fixture: A device or attachment fastened to or propelled by the conveying medium; used for supporting or securing objects being processed as they are conveyed.

Floor Conveyor: Any of several types of conveyors using chain, cable, or other linkage mounted near or flush with the floor for the purpose of assembling, or finishing built-up products and subassemblies.

Flow: The direction of travel of the product on the conveyor.

Frame: The structure which supports the machinery components of a conveyor.

Friction Clutch: Any clutch in which driving effort is developed by contact between pressure elements through friction alone. General use is for the purpose of engaging and disengaging revolving parts. Also used as a safety device to permit slip when overload occurs.

Gate: A device or structure by means of which the flow of may be stopped or regulated. Also, a section of conveyor equipped with a hinged mechanism for movable service often called a hinged section.

Gearmotor: A motor and speed reducer combination where the two units are flanged for connection to each other and have one output shaft; or where the two units are closely coupled with the motor resting on a base which is an integral party of the speed reducing housing.

Gravity Conveyor: Roller or wheel conveyor over which objects are advanced manually by gravity.

Guard Rail: Members paralleling the path of a conveyor and limiting the objects or carriers to movement in a defined path.

Horsepower: A measure of the time rate of doing work defined as the equivalent of raising 33,000 pounds one foot in one minute. Electrically, one horsepower is 746 watts.

Hertz: Electrical terminology, a unit of frequency equal to one cycle per second. Most common cycle time is 60 Hertz.

Idler: A pulley, sheave, sprocket, or wheel around which a belt, cable, or chain passes in changing direction of travel.

Idler Roller: Any carrying roller of a live roller conveyor not driven.

Indexing: A method of control to obtain predetermined intermittent movements.

Knee Brace: A structural brace at an angular position to another structural component for the purpose of providing support and/or stability of the conveyor frame.

Lagged Pulley: A pulley having the surface of its face crowned with a material to provide for greater friction with the belt.

Limit Switch: A mechanical device which, when activated, opens or closes contacts to alter the control circuit.

Lineshaft Conveyor: A roller conveyor with carrying rollers individually powered by drive belts from a rotating shaft.

Live Roller Conveyor: A series of rollers over which objects are moved by the application of power to all or some of the rollers.. The power transmitting medium is usually belting or chain.

Load: The total weight on the conveyor.

Load Cell: A device which produces an output signal proportional to the applied load.

Magnetic Brake: A brake usually mounted on a motor shaft with means to engage automatically when the electric current is cut off or fails.

Magnetic Starter: An electrical device which controls the motor and also provides overload protection to the motor.

MDR: Acronym for Motorized Drive Roller.

Meter Belts: One or more in-line conveyors used to provide controlled material discharge.

Minimum Pressure Accumulation Conveyor: A type of conveyor designed to minimize build-up of pressure between adjacent packages or cartons.

Motor: A machine which transforms electric energy into mechanical energy.

Motorized Drive Roller: A hollow roller with a brushless DC motor inside.

Motorized Pulley: A drive unit consisting of a motor, gears, pulley and shaft combination wherein the pulley face (rim) is the rotating member. The shaft is stationary and the gears and motor windings are within the pulley enclosure.

Nose-Over: Curved or segmented frame sections having rollers properly spaced to provide a transition from incline to level or from level to decline.

Pallet: A flat or shaped wheelless load carrier of a pallet conveyor.

Pillow Block: A bearing block or housing having a flat mounting surface offset, but parallel to the shaft.

Pop-Out Roller: A special load carrying roller mounted in such a manner as to pop out when foreign objects are introduced between the belt and the roller.

Power Belt Curve: A curve conveyor which utilizes a belt, driven by tapered pulleys.

Power Conveyor: Any type of conveyor which requires power to move its load.

Powered Feeder: A driven length of belt conveyor, normally used to move product horizontally onto an incline conveyor.

Pressure Roller: A roller used for holding the driving belt in contact with the load carrying rollers in a belt drive live roller conveyor.

Product Stop: A mechanical barrier to interrupt the flow of product on an active conveyor, that is, without shutting down the conveyor. Typically, a product stop is pneumatically actuated. Also known as Case Stop.

Programmable Logic Controller (PLC): A device that is pre-programmed to accept relay ladder logic instructions and perform these instructions to control the equipment operation.

Proximity Switch: A switch actuated by the presence of an object near its operating head.

Pulley: A cylindrical member, but sometimes polygonal in cross section with provision for mounting on a shaft.

Pusher: A powered mechanical device mounted on or adjacent to a conveyor that, when activated, will transfer material handled from or to the conveyor.

Push Button Station: An electrical enlosure which houses Push Button.

Reversible Conveyor: A conveyor which is designed to move product in either direction.

Roller: A round part free to revolve about its outer surface. The face may be straight, tapered or crowned. Rollers may also serve as the rolling support for the load being conveyed.

Roller Bed: A series of rollers used to support a conveying medium.

Roller Conveyor: Series of rollers supported in a frame over which objects are advanced manually, by gravity or by power.

Rough Top Belt: A belt cover intentionally made with irregular ridges or projection to produce a broken surface for greater traction or carrying abilities. Used for inclined service.

Shaft: A bar, usually of steel and usually round, to support rotating parts or to transmit power.

Sheave: A wheel with a grooved rim used with ropes, cables, belts, etc.

Singulation Mode: Mode where packages are- automatically separated while traveling down the conveyor.

Skate-wheel Conveyor: A type of wheel conveyor making use of series of skate-wheels mounted on common shafts or axles, or mounted on parallel spaced bars on individual axles.

Slider Bed: A stationary surface on which the carrying run of a belt conveyor slides.

Slug Mode: Allows all packages to be released simultaneously.

Sortation Conveyor: Conveyor which is able to sort different packages or products to specific take-away lines.

Speed: The rate at which product moves on conveyor.

Speed Reducer: A power transmission mechanism designed to provide a speed for the driven equipment less than that of the prime mover. Speed reducers may have either constant speed or adjustable speed. They are generally totally enclosed to retain lubricant and prevent the entry of foreign materials.

Sprocket: A wheel with suitably shaped and spaced cogs or teeth to engage with the links of a chain.

Spur: A gravity or powered conveyor section to switch unit loads to and from the main line.

Take-up: The assembly of the necessary structural and mechanical parts which provides the means to adjust the length of belts, cables, chains, etc. to compensate for stretch, shrinkage, or wear and to maintain proper tension.

Take-up Belt Tension: The actual amount of tension in each of the two runs of conveying medium approaching and leaving the take-up.

Take-up Pulley: A pulley mounted on the take-up shaft.

Tapered Roller: A conveyor roller for use in a curve with end and intermediate diameters proportional to their distance from the center of the curve.

Transfer: A device or series of devices, usually mounted inside a conveyor section, which uses belts, chains, o-rings, rollers, or skate- wheels, to move products at right angles to adjacent or parallel conveyor lines.

Trough: A channel generally longer than its width, open at the top, or fitted with a cover, which contains the material being conveyed.

Turntable: Horizontal, rotatable conveyor mechanism used for transferring objects between conveyors which are in angular relation to one another.

Variable Speed Drive: A drive or power transmission mechanism that includes a speed changing device.

Zero Pressure Accumulation Conveyor: A type of conveyor designed to eliminate build-up of pressure between adjacent packages or cartons.