Motor Starters are switches specially made for starting motors. These switches are made to control the flow of current. There are basically two types of motor starters, Manual Starters and Magnetic Starters.
Uses of STARTER Inside a Motor :
1: To give starting resistance to motor.
2:Starter is employed to safe the motor winding from the high starting
current.
3: Starter is employed in a motor to control the limit of high starting current. As the motor starts(in case of DC motor) high current occurs which is handled by use of high resistance slowly cut from the circuit.
History
Both Otto cycle and Diesel cycle internal-combustion engines require the pistons which can be used to convert pressure into motion.
Originally, a hand crank(handle) was used to begin engines, but it was difficult, and dangerous to start an engine. Even though cranks had an overrun mechanism, when the engine started, the crank could begin to spin along with the crankshaft and it could strike the individual starting the engine. Care has to be taken to avoid the spark from backfiring. In short we can say that there is a lot of risk while starting the engine with a a crank. Moreover, increasingly larger engines with higher compression ratios made hand cranking a more challenging endeavour.
While there was a need of starter, such as 1899, Clyde J. Coleman applied for U. S. Patent 745, 157 for an electric automobile self-starter - inventing one that worked successfully generally in most conditions didn't occur until 1911 when Charles F. Kettering of Dayton Engineering Laboratories Company (DELCO) invented and filed for U. S. Patent 1, 150, 523 for the first useful electric starter. (Kettering had replaced the hand crank on NCR's cash registers with a power motor five years earlier. ) One aspect of the invention lay in the realization a relatively small motor, driven with higher voltage and current than would be feasible for continuous operation, could deliver enough capacity to crank the engine for starting. In the voltage and current levels required, such a motor would burn out in a few minutes of continuous operation, however, not during the couple of seconds needed to start the engine. The starters were first installed by Cadillac on production models in 1912. The Model T relied on hand cranks until 1919; by 1920 most manufacturers included self-starters. The electric starter ensured that anyone could easily start and run an internal combustion engine car, which made it the look of preference for car buyers from that day forward.
Details about the Starters used->
Following starters used to use motor starter
Gear reduction starter
Pneumatic starter
The Principal of which motor starter is worked
Electric starter used in motor starter
Electric starter
Main Housing
Armature
Field coils
Brushes
What is motor starter?
"A starter motor is a high-torque electric motor for turning the gear on the engine flywheel. "
The modern starter motor is either a permanent-magnet or a series-parallel wound direct current electric motor with a solenoid switch (similar to a relay) mounted on it. When current from the starting battery is put on the solenoid, usually by way of a key-operated switch, it pushes out the drive pinion on the starter driveshaft and meshes the pinion with the ring gear on the flywheel of the engine. Before the advent of key-driven starters, most electric starters were actuated by foot-pressing a pedestal on the floor, generally above the accelerator pedal.
Solenoid
The solenoid also closes high-current contacts for the starter motor, which commences to turn. After the engine starts, the key-operated switch is opened, a spring in the solenoid assembly pulls the pinion gear away from the ring gear, and the starter motor stops. The starter's pinion is clutched to its driveshaft via an overrunning sprag clutch which permits the pinion to transmit drive in only one direction. This way, drive is transmitted through the pinion to the flywheel ring gear, but if the pinion remains engaged (as for example because the operator fails to release the key when the engine starts), the pinion will spin independently of its driveshaft. This prevents the engine driving the starter, for such backdrive would cause the starter to spin so fast concerning fly apart. However, this sprag clutch arrangement would preclude the utilization of the starter as a generator if employed in hybrid scheme mentioned above; unless modifications are created. Also, a typical starter motor is merely suitable for intermittent use which would preclude its use as a generator.
Overrunning clutch
This overrunning-clutch pinion arrangement was phased into use from the early 1960s; before that point, a Bendix drive was used. The Bendix system places the starter drive pinion on a helically-cut driveshaft. If the starter motor starts turning, the inertia of the drive pinion assembly causes it to ride forward on the helix and so engage with the ring gear. When the engine starts, backdrive from the ring gear causes the drive pinion to exceed the rotative speed of the starter, at which point the drive pinion is forced back off the helical shaft and so out of mesh with the ring gear.
An intermediate development between the Bendix drive developed in the 1930s and the overrunning-clutch designs introduced in the 1960s was the Bendix Folo-Thru drive. The typical Bendix drive would disengage from the ring gear when the engine fired, even if it did not continue steadily to run. The Folo-Thru drive contains a latching mechanism and a set of flyweights in the body of the drive unit. If the starter motor starts turning and the drive unit is forced forward on the helical shaft by inertia, it is latched in to the engaged position. Only once the drive unit is spun at a speed higher than that attained by the starter motor itself (i. e. , it is backdriven by the running engine) will the flyweights pull radially outward, releasing the latch and permitting the overdriven drive unit to be spun out of engagement. This way, unwanted starter disengagement is avoided before a successful engine start.
Starter found in motor starter :
Gear-reduction starters
Chrysler Corporation contributed materially to the modern development of the starter motor. In 1962, Chrysler introduced a starter incorporating a geartrain between your motor and the driveshaft. Rolls Royce had introduced a conceptually similar starter in 1946, but Chrysler's was the first volume-production unit. The motor shaft has integrally-cut gear teeth forming a drive gear which mesh with a more substantial adjacent driven gear to give a gear reduction ratio of 3. 75:1. This permits the utilization of any higher-speed, lower-current, lighter and more compact motor assembly while increasing cranking torque. Variants of the starter design were applied to most vehicles produced by Chrysler Corporation from 1962 through 1987. The Chrysler starter made a unique, readily identifiable sound when cranking the engine.
This starter formed the design basis for the offset gear reduction starters now utilized by about half the vehicles on the highway, and the conceptual basis for practically most of them. Many Japanese automakers phased in gear reduction starters in the 1970s and 1980s. Light aircraft engines also made extensive use of this kind of starter, because its light weight offered an advantage.
Those starters not employing offset geartrains like the Chrysler unit generally employ planetary epicyclic geartrains instead. Direct-drive starters are almost entirely obsolete owing to their larger size, heavier weight and higher current requirements. Ford also issued a nonstandard starter, a direct-drive "movable pole shoe" design that provided cost reduction rather than electrical or mechanical benefits. This type of starter eliminated the solenoid, replacing it with a movable pole shoe and a separate starter relay.
The Ford starter operated as follows:
The operator closed the key-operated starting switch.
A small electric current flowed through the starter relay coil, closing the contacts and sending a large current to the starter motor assembly.
One of the pole shoes, hinged at the front, linked to the starter drive, and spring-loaded from its normal operating position, swung into position. This moved a pinion gear to engage the flywheel ring gear, and simultaneously closed a set of heavy-duty contacts supplying current to the starter motor winding.
The starter motor cranked the engine until it started. An overrunning clutch in the pinion gear uncoupled the apparatus from the ring gear.
The operator released the key-operated starting switch, cutting capacity to the starter motor assembly.
A spring retracted the pole shoe, and with it, the pinion gear.
FEATURES / BENEFITS
It really is Compact.
It has high torque.
It has high durability.
It has self-contained clutch shaft.
Electric starter
The modern starter motor is the permanent-magnet or a series-parallel wound direct current electric motor with a solenoid switch (similar to a relay) mounted on it. When current from the starting battery is applied to the solenoid, usually by way of a key-operated switch, it pushes out the drive pinion on the starter driveshaft and meshes the pinion with the ring gear on the flywheel of the engine. Prior to the advent of key-driven starters, most electric starters were actuated by foot-pressing a pedestal on the floor, generally above the accelerator pedal.
The solenoid also closes high-current contacts for the starter motor, which begins to turn. After the engine starts, the key-operated switch is opened, a spring in the solenoid assembly pulls the pinion gear from the ring gear, and the starter motor stops. The starter's pinion is clutched to its driveshaft via an overrunning sprag clutch which permits the pinion to transmit drive in mere one direction. In this manner, drive is transmitted through the pinion to the flywheel ring gear, if the pinion remains engaged (as for example because the operator fails to release the key when the engine starts), the pinion will spin independently of its driveshaft. This prevents the engine driving the starter, for such backdrive would cause the starter to spin so fast concerning fly apart. However, this sprag clutch arrangement would preclude the use of the starter as a generator if employed in hybrid scheme mentioned previously; unless modifications are made. Also, a typical starter motor is merely designed for intermittent use which would preclude its use as a generator.
This overrunning-clutch pinion arrangement was phased into use beginning in the first 1960s; before that point, a Bendix drive was used. The Bendix system places the starter drive pinion over a helically-cut driveshaft. If the starter motor begins turning, the inertia of the drive pinion assembly causes it to ride forward on the helix and thus build relationships the ring gear. When the engine starts, backdrive from the ring gear causes the drive pinion to exceed the rotative speed of the starter, of which point the drive pinion is forced back off the helical shaft and thus out of mesh with the ring gear.
An intermediate development between your Bendix drive developed in the 1930s and the overrunning-clutch designs introduced in the 1960s was the Bendix Folo-Thru drive. The standard Bendix drive would disengage from the ring gear as soon as the engine fired, even if it did not continue to run. The Folo-Thru drive contains a latching mechanism and a couple of flyweights in the torso of the drive unit. When the starter motor starts turning and the drive unit is forced forward on the helical shaft by inertia, it is latched in to the engaged position. Only one time the drive unit is spun at a speed higher than that achieved by the starter motor itself (i. e. , it is backdriven by the running engine) will the flyweights pull radially outward, releasing the latch and permitting the overdriven drive unit to be spun out of engagement. In this manner, unwanted starter disengagement is avoided before an effective engine start.
The modern starter motor is a series-wound direct current electric motor with a solenoid switch (similar to a relay) mounted onto it. When low-current power from the starting battery is applied to the solenoid (the thin, grey wire in the image above), usually by way of a key-operated switch, it pushes out a small pinion gear on the starter motor's shaft and meshes it with the ring gear on the flywheel of the engine. The solenoid also closes high-current contacts (powered through the thick red cable in the image) for the starter motor and it starts to perform. After the engine starts, the key-operated switch is opened, a spring in the solenoid assembly pulls the pinion gear from the ring gear, and the starter motor stops. Modern starter motors have a "bendix" a gear and integral freewheel, or overrunning clutch, that allows the flywheel to automatically disengage the pinion gear from the flywheel when the engine starts.
Chrysler and Ford both contributed to the starter market, with two types which were very different to prospects applied to vehicles today.
Chrysler produced a gear reduction starter employing a small gear to drive a more substantial gear attached to the starter's pinion gear shaft. This allowed lower current to be drawn from the battery to perform the starter, but still had the original torque needed to turn the flywheel approximately at 200 rpm. This starter is also smaller and integrates the starter solenoid in the starter case, instead of having it mounted externally. Since this design weighs less, it has also been adapted to some light aircraft engines, where minimizing weight is very important.
Ford's version was slightly more difficult. The engineers at Ford Motor Company used a "positive engagement" style starter. This type of starter eliminated the solenoid, replacing it with a moveable armature and another starter relay. An armature is a component made of ferromagnetic metal that is magnetized by a coil of copper ribbon wound around it, creating an electromagnet. The Ford starter operated as follows:
The operator closed the key-operated starting switch.
A small electric energy flowed through the starter relay coil, closing the contacts and sending a sizable current to the starter motor assembly.
The armature moved a pinion gear to engage the flywheel ring gear, and simultaneously closed a pair of heavy-duty contacts supplying current to the starter motor winding.
The starter motor cranked the engine until it started. An overrunning clutch in the pinion gear uncoupled the apparatus from the ring gear.
The operator released the key-operated starting switch, cutting capacity to the starter motor assembly.
A spring retracted the armature, and with it, the pinion gear.
Current Ford starter designs incorporate the starter solenoid in to the starter motor assembly, instead of mounting it on the firewall or on the fender.
Starter motor
A starter can be an electric motor had a need to turn over the engine to start out it.
A starter contains the very powerful DC electric motor and starter solenoid that is mounted on the motor (start to see the picture).
A starter motor requires very high current to crank the engine, that's why it's connected to the battery with large cables (see lower diagram).
The negative (ground) cable connects "-"battery terminal to the engine block near the starter.
The positive cable connects "+"battery terminal to the starter solenoid.
The starter solenoid works as a power switch - when actuated, it closes the circuit and connects the starter motor to the battery. At the same time, it pushes the starter gear forward to mesh with the engine's flywheel.
How the starting system works:
When you turn the ignition key to the "Start"position, the battery voltage undergoes the starter control circuit and activates the starter solenoid, which in turn energizes the starter motor. The starter motor cranks the engine.
A starter can only just be operated when the programmed transmission shifter is "Park"or "Neutral"position or if the automobile has a manual transmission, when the clutch pedal is depressed.
To accomplish this, there is a Neutral safety switchinstalled at the programmed transmission, (or at the clutch pedal).
When the computerized transmission is not in "Park"or "Neutral"(or when the clutch pedal is not depressed), the neutral safety switch is open and the starter relay disconnects the starter control circuit.
Simplified diagram of typical starting system
Pneumatic Starter
A Pneaumatic motor is a machine which converts by means of compressed air into mechanical work. It converts it either in linear or rotary motion. Linear motion will come from piston actuator, while rotary motion comes by a piston air motor. These motors are very successful in hand-held tool industry.
Classification
Linear
In order to achieve linear motion from compressed air, something of pistons is mostly used. The compressed air is pumped into an air tight chamber that houses the shaft of the piston. Also inside this chamber a spring is coiled across the shaft of the piston to be able to carry the chamber completely open when air is not being pumped into the chamber. As air is pumped into the chamber the force on the piston shaft commences to overcome the force being exerted on the spring. As more air is pumped into the chamber, the pressure increases and the piston commences to go down the chamber. When it reaches its maximum length mid-air pressure is released from the chamber and the spring completes the cycle by closing off the chamber to come back to its original position.
Piston motors are the most commonly found in hydraulic systems. Essentially, piston motors are the identical to hydraulic pumps except they are used to convert hydraulic energy into mechanical energy. Piston motors tend to be used in group of two, three, four, five, or six cylinders that are enclosed in a housing. This allows for more power to be delivered by the pistons because several motors are in sync with one another at certain times of their cycle
Rotary
Another kind of pneumatic motor, known as a rotary vane motor, uses air to create rotational motion to a shaft. The rotating element is a slotted rotor which is attached to a drive shaft. Each slot of the rotor is fitted with a freely sliding rectangular vane. [3] The vanes are extended to the housing walls using springs, cam action, or air pressure, depending on the motor design. Air is pumped through the motor input which pushes on the vanes creating the rotational motion of the central shaft. Rotation speeds can vary between 100 and 25, 000 rpm depending on several factors which like the amount of air pressure at the motor inlet and the diameter of the housing. [1]
Rotary motion vane type air motors are being used to get started on large industrial diesel or natural gas engines. Stored energy by means of compressed air, nitrogen or natural gas enters the sealed motor chamber and exerts pressure against the vanes of the rotor. Much like a windmill, this causes the rotor to turn at high speed. As the engine flywheel requires a lot of torque to start out the engine, reduction gears are being used. Reduction gears to produce high torque levels with the lower levels of energy input. These reduction gears enable sufficient torque to be made by the engine flywheel while it is engaged by the pinion gear of the air motor or air starter.
Application
A widespread application of small pneumatic motors is in hand-held tools, power ratchet wrenches, drills, sanders, grinders, cutters, and so forth. Though overall energy efficiency of pneumatics tools is low and they require usage of a compressed-air source, there are several advantages over electric tools. They provide greater power density (an inferior pneumatic motor can provide the same amount of power as a larger electric motor), do not require an axillary speed controller (increasing its compactness), generate less heat, and can be utilized in more volatile atmospheres as they don't require energy. Some gas turbine engines and Diesel engines, particularly on trucks, use a pneumatic self-starter. The machine involves a geared turbine, an air compressor and a pressure tank. Compressed air released from the tank can be used to spin the turbine, and through a couple of reduction gears, engages the ring gear on the flywheel, much like an electric starter. The engine, once running, powers the compressor to recharge the tank.
On larger diesel generators within large shore installations and especially on ships, a pneumatic starting gear can be used. The environment motor is generally powered by compressed air at pressures of 10-30 bar. The air motor comprises of a center drum about how big is a soup can with four or even more slots cut involved with it to permit for the vanes to be located radially on the drum to create chambers across the drum. The drum is offset inside a round casing so the inlet air for starting is admitted at the region where the drum and vanes form a tiny chamber set alongside the others. The compressed air can only expand by rotating the drum that allows the tiny chamber to become larger and puts another one of the cambers in the air inlet. The air motor spins much too fast to be utilized directly on the flywheel of the engine, instead a big gearing reduction like a planetary gear can be used to lessen the output speed. A Bendix gear is utilized to activate the flywheel.
Some smaller diesel engines such as ones entirely on tugboats and lifeboats use hydraulic start motors in which the air motor is replaced with a hydraulic motor. While running, the engine must not be shut down unless the hydraulic accumulators for the starting motor are recharged. Otherwise there's a manual hand pump to slowly increase the accumulators.
Since large trucks typically use air brakes, the machine does double duty, supplying compressed air to the brake system. Pneumatic starters have benefits of delivering high torque, mechanical simplicity and reliability. They eliminate the need for oversized, heavy storage batteries in prime mover electrical systems.
BIBLOGRAPHY
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