Posted tagged ‘motion’

Oscillating Conveyor System

September 8, 2011

Selection of vibratory conveyor:

01-vibrating conveyor-vibrating conveyor applications-vibrating conveyor belt-vibrating conveyor motor-oscillator-reciprocating conveyor-shaker conveyor-inertia conveyor

The oscillating motion of the trough is achieved via specially designed inclined arms and an eccentric shaft driven by a motor through V-belts. The eccentric shaft is mounted on anti friction bearings and has V-pulleys at both ends with weights on them to counteract the unbalancing force. The rotation of the eccentric shaft provides a forward and backward motion to a connecting arm attached to the trough through a rubberized pin. The trough motion is predominantly horizontal with some vertical component, which causes it to oscillate with a pattern conductive to conveying material. A retaining spring assembly at the back of the trough absorbs shock load. All components including drive motor are mounted on a rigidly constructed base frame.


· Hot and abrasive materials can be handled

· Cooling, drying and de-watering operation can be done during transport

· Scalping, screening or picking can be done

· Units can be covered and made dust tight

· Simple construction and low head room

· Can be made leak proof


· Relatively short length of conveying ( about 50m Maximum)

· Limited capacity, about 350 tons per hour for length of conveying of 30 m.

· Some degradation of material takes place.


Vibratory conveyors find wide spread application in the transportation of dusty, hot, toxic, and chemically aggressive bulk material through a closed trough or pipe in chemical, metallurgical, mining industries and manufacturing of building materials.

Vibratory conveyors are also employed for transportation of steel chips in machine shop, hot knocked out sand, wastes and small castings in foundry shop. Vibratory feeders are also in use for delivery of small machine parts like screws, rivets etc.

Sticky materials like wet clay or sand are unsuitable for vibratory conveyors. In handling finely pulverized materials, like cement etc., the performance of such conveyors are reported to be poor.

Vibratory conveyors are hardly employed for handling common bulk loads, such as sand, gravel, coal etc as the same can be done more efficiency by belt conveyors.


August 23, 2011

Jib crane have the following motions:

    1. Hoisting motion
    2. Derricking or luffing motion
    3. Slewing motion
    4. Long travel motion

Hoisting motion:

It is used to lift or lower the load. This is usually achieved by steel wire ropes being affixed to a crane hook or a grab hanging from the outer end of the jib. The rope is applied through some receiving arrangement and controlled and operated by a winch system.

01-crane hoist-tower crane-electric hoist-jib crane motion-to lift or lower the load-steel wire ropes

Derricking or Luffing motion:

It is imparted to the inclined member or the jib to move in a vertical plane so that the angle of the jib may be changed in order to bring the load line nearer to or further off from the centre of the crane.

01-derricking motion-luffing motion-of jib cranes-jib move in vertical plane

Slewing motion:

It is imparted to the whole super structure of the crane including the jib, so that it can turn about a central pivot shaft w.r.t. the non-revolving parts. This motion enables the crane to shift the load line to revolve round the crane.

01-wall mounted jib crane-for handling light weight materials-slewing motion

Long Travel Motion:

It may be required when the whole crane structure has to be shifted to a distant place along a rail track or along a road.

01-crawler mounted mobile jib cranes-travelling type jib cranes-power driven cranes-long travel motion

Jib crane consists of an inclined member supported by a rope or any other type of structural member attached to a vertical mast or frame. Load is usually suspended from the outer end of this inclined mast. The outreach of the jib may be fixed or variable. The cranes as a whole may be either fixed or moveable. Various sub-classification of these cranes are possible.

Lifting capacity of such cranes may vary from 1/2 ton to 200 ton and outreach from a few meter to 50 meter. Such cranes find various applications in port area, construction site, and other outdoor works.

For handling general cargo, lifting capacities are usually 1  1/2 ton to  5 ton with maximum outreach of 30 meter. Jib Cranes provided with grabbing facilities have usually a capacity ranging from 3 to 20 tons operating 50 to 100 cycles per hour. Lifting heights may be 30 meters or more.

Jib crane used in ship yards for lifting heavy machinery and equipment, weighing 100 to 300 tons, are usually mounted on pontoons. Frequently these cranes are provided with two main hoisting winches which can be employed singly or together to lift a load. For handling light loads these cranes may have auxiliary arrangement.

Types Of Jib Crane:

Depending on the use, jib cranes are classified into a number of varieties, primarily on the basis of their mountings.

These are:

    1. Hand Operated Scotch Derrick Type
    2. Wall Mounted Jib crane
    3. Portal / Semi-portal cranes of different varieties-Wharf cranes
    4. Mobile jib cranes consisting of truck mounted and crawler mounted cranes

Scotch Derrick Type / Wall Cranes:

01-wall mounted jib crane-for handling light weight materials

Wall cranes are used in ware houses for handling light weight and when there is little or no wharf between them and the water front. Slewing or rotational motion of the crane is possible within restricted angle and the motion is slow. Hoisting and lifting speeds are comparable to those of wharf cranes. In some modified version these cranes can have travelling speed along the wall.

01-scotch derrick cranes-hand operated jib crane

Wharf Cranes:

These are used in shipyard and port for handling unit and bulk load. These are usually self propelled balanced level luffing type with full circle slewing motion facility. Wharf cranes may be of different types, depending on the type of structure on which it is mounted.  The choice of structure for mounting depends on site condition.

01-wharf cranes-semi portal cranes-full portal cranes-jib cranes-girders connected at both the ends

The principal types of wharf cranes are:

  • High pedestal
  • Full Portal
  • Semi-portal

Portal Cranes:

Portal crane is a fixed or revolving type jib crane mounted on a portal frame fixed in location or arranged to travel along a fixed track of rails at the same level. The portal frame consists essentially of horizontal girders connected at both ends to vertical or inclined member’s having equal lengths.

Semi portal Crane:

Semi portal crane is a fixed or revolving type jib crane mounted on a semi portal frame fixed in location or arranged to travel along a fixed track or rails at different levels. The semi portal frame essentially consists of horizontal girders connected at both ends to vertical or inclined members which constitute a shorter side and a longer side. The shorter members may consist only of the trolley running along the elevated rail.

01-semi portal cranes-full portal cranes-wharf crane-types of jib crane

Mobile crane:

Mobile Crane ( Power Driven ) includes all type of travelling jib cranes, such as truck mounted, crawler mounted, locomotive crane on rails.

01-crawler mounted mobile jib cranes-travelling type jib cranes-power driven cranes


01-mobile cranes-travelling jib cranes-Truck mounted jib crane


August 23, 2011

01-wind up battery-crank up battery-battery storage technology-hand powered spinning re-charger battery

The Wind up battery is the endless independent source of power. It is the only tool you will need to charge your mobile phone batteries, notebook batteries, GPS or any other modern gadget which is in this information-packed world essential life companion. The use of wind up battery charger is easy and being that it is totally portable and independent power supply, it is a valuable part of accessory of every trekker’s, backpacker’s, traveler’s adventures journey. It is also an essential back up power supply for any critical emergency events when there is no power supply available nearby.

How does it work?

01-wind up battery- operation-working-twisting clockwise or anticlockwise makes charging

The wind up battery mechanism uses internal generator, which is usually hand-powered by spinning the handle on the device. The hand motion, in which AC alternator is driven by a crank converts human mechanical energy and generates the electrical power, by spinning magnets past a coil of wire, which is stored in battery. To charge the device, utilizing the wind up mechanism the hand crank needs to be pulled out of the folded position, and spun in clockwise/counterclockwise direction. After some time of cranking, when the device is charged the handle is folded into position and the device is available to use.

There are also foot powered wind up battery devices, which generate power and self charge by human energy through step action. These are able to jump-start a boat or automobile battery, and power a wide array of instruments and accessories and present a valuable and versatile tool for power supply.

The Devices using wind up mechanism

There are several devices on market which utilize the wind up mechanism. It can be used as a wind up battery charger, wind up flashlight, wind up radio, wind up clock, mp3 player, or a larger electricity supply unit. Usually there are hand cranks folded into the devices, which can be pulled out when needed. The wind up devices are a great way to promote environmentally clean green energy source as the power is derived through windup mechanism which efficiently harvests the human energy and converts it to electricity.

If you are an environmentally conscious consumer who likes to travel and have a power charger available for his electric devices and an emergency power supply then the wind up battery is the device to look for.

01-exploded view of wind up battery-wind up mechanism


August 23, 2011

An electrochemical reaction occurs between hydrogen and oxygen that converts chemical energy into electrical energy.

01-how fuel cell works-proton exchange membrane-hydrogen fuel cell

Think of them as big batteries, but ones that only operate when fuel—in this case, pure hydrogen—is supplied to them. When it is, an electrochemical reaction takes place between the hydrogen and oxygen that directly converts chemical energy into electrical energy. Various types of fuel cells exist, but the one automakers are primarily focusing on for fuel cell cars is one that relies on a proton-exchange membrane, or PEM. In the generic PEM fuel cell pictured here, the membrane lies sandwiched between a positively charged electrode (the cathode) and a negatively charged electrode (the anode). In the simple reaction that occurs here rests the hope of engineers, policymakers, and ordinary citizens that someday we’ll drive entirely pollution-free cars.

Here’s what happens in the fuel cell: When hydrogen gas pumped from the fuel tanks arrives at the anode, which is made of platinum, the platinum catalyzes a reaction that ionizes the gas. Ionization breaks the hydrogen atom down into its positive ions (hydrogen protons) and negative ions (electrons). Both types of ions are naturally drawn to the cathode situated on the other side of the membrane, but only the protons can pass through the membrane (hence the name “proton-exchange”). The electrons are forced to go around the PEM, and along the way they are shunted through a circuit, generating the electricity that runs the car’s systems.

Using the two different routes, the hydrogen protons and the electrons quickly reach the cathode. While hydrogen is fed to the anode, oxygen is fed to the cathode, where a catalyst creates oxygen ions. The arriving hydrogen protons and electrons bond with these oxygen ions, creating the two “waste products” of the reaction—water vapor and heat. Some of the water vapor gets recycled for use in humidification, and the rest drips out of the tailpipe as “exhaust.” This cycle proceeds continuously as long as the car is powered up and in motion; when it’s idling, output from the fuel cell is shut off to conserve fuel, and the ultra capacitor takes over to power air conditioning and other components.

A single hydrogen fuel cell delivers a low voltage, so manufacturers “stack” fuel cells together in a series, as in a dry-cell battery. The more layers, the higher the voltage. Electrical current, meanwhile, has to do with surface area. The greater the surface area of the electrodes, the greater the current. One of the great challenges automakers face is how to increase electrical output (voltage times current) to the point where consumers get the power and distance they’re accustomed to while also economizing space in the tight confines of an automobile.