What is Governor in theory of machine ? What are it's types ?
Definition of governor and write the types of Governer in theory of machine.
GOVERNOR
The function of a governor is to control the mean speed of the engine with specified limits whenever there is a variation of load.
When the load on the engine increases, the engine speed gets decreases, then the governor supply the extra fuel to maintain the constant speed of the engine. On the other hand, when the load on the engine decreases, its speed increases and thus less working fluid is required which is also controlled by the governor.
Hence we can say that, the governor automatically controls the supply of working fluid to the engine with the varying load conditions and keep the mean speed with certain limits.
In the theory of machines, a governor refers to a mechanical device that is used to regulate the speed of a machine, such as an engine or a turbine, by controlling the flow of energy. The primary function of a governor is to maintain a constant speed of the machine, despite changes in the load or external conditions.
The governor system works based on the principle of centrifugal force. It consists of a rotating shaft connected to the machine being controlled and a set of rotating masses or balls attached to the shaft. These balls are connected to a mechanism that adjusts the input of energy to the machine.
As the machine's speed increases, the centrifugal force acting on the rotating masses also increases. This causes the balls to move outward, which, in turn, adjusts the mechanism controlling the energy input. By adjusting the energy input, the governor counteracts the increase in speed and brings it back to the desired set point.
Conversely, if the speed of the machine decreases, the centrifugal force decreases, causing the balls to move inward. This adjustment increases the energy input to the machine, compensating for the decrease in speed and maintaining the desired set point.
Governors are commonly used in various applications, such as steam engines, hydroelectric turbines, and internal combustion engines, to ensure smooth and stable operation.
They play a vital role in maintaining the desired speed and preventing the machine from running too fast or too slow, which can lead to inefficiencies, mechanical stresses, or even catastrophic failures.
Types of Governer
In the theory of machines, a governor is a device used to regulate the speed of engines, particularly steam engines. It controls the fuel supply to the engine in order to maintain a constant speed under varying load conditions.
There are two main types of governors :-
1. Centrifugal governors and
2. Inertia governors
The centrifugal governors may further classified as follows :-
(a) Pendulum Type
( i ) Watt Governor
(b) Loaded Type
( i ) Dead Weight Governors :- Porter Governor and Proell Governor.
( ii ) Spring Controlled Governor :- Hartnell Governor , Hartung Governor , Wilson - Hartnell Governor and Pickering Governor.
( 1 ) CENTRIFUGAL GOVERNER
The centrifugal governors are based on ther balancing of centrifugal force on the rotating balls by an equal and opposite radial force known as controlling force. This is the most common type of governor. Its working depends upon the change of speed. It has pair of masses, which is known as governor balls, which rotate with a spindle.
The spindle is driven by an engine through bevel gears. With the increase in the speed, the balls tend to rotate at a greater radius from the axis and through a suitable linkage. The throttle value is made to close to the required extent.
When the speed decreases the balls rotate at a smaller radius and the value is opened according to the requirement.
A centrifugal governor is a mechanical device used to control and regulate the speed of engines or machines by controlling the supply of fuel or the mechanical power input. It works based on the principle of centrifugal force.
The governor typically consists of a rotating shaft driven by the engine or machine being controlled. Attached to this shaft are a set of rotating weights or balls that are connected to a linkage mechanism. As the shaft rotates, the centrifugal force generated by the rotating weights causes them to move outward.
The linkage mechanism translates this outward movement into a change in the fuel supply or power input, thereby controlling the speed.
The centrifugal governor operates based on the principle of negative feedback. When the speed of the engine or machine increases, the rotating weights move outward due to increased centrifugal force. This, in turn, closes a valve or reduces the power input, reducing the speed.
Conversely, when the speed decreases, the weights move inward, opening the valve or increasing the power input, thus increasing the speed.
Centrifugal governors have been widely used in various applications, such as steam engines, internal combustion engines, and industrial machinery, to maintain a constant speed and prevent overspeeding.
They were particularly popular during the industrial revolution when reliable speed control mechanisms were needed to regulate the operation of machines. However, with the advancements in electronic control systems, centrifugal governors have been largely replaced by electronic speed control methods in many modern applications.
( 2 ) INERTIA GOVERNOR
In the type of Inertia governor, the position of the balls are effected by the forces set up by an angular acceleration or deceleration of the given spindle in addition to the centrifugal forces on the fly balls. Using suitable linkage and springs, the change in position of the balls is made to open or close the throttle value.
Thus whereas the value is operated by the actual change of the engine speed in the case of centrifugal governors. It is by the rate of change of speed in case of inertia governor. Therefore , the response of inertia governor is faster than that of the centrifugal governors.
An inertia governor, also known as a fly balls governor, is a mechanical device used to regulate the speed of a machine, typically a steam engine or a reciprocating engine. It is an important component in older mechanical systems and was commonly used in the 19th and early 20th centuries.
The purpose of an inertia governor is to maintain a constant speed of the engine or machine, regardless of the fluctuations in the load. It does this by controlling the fuel supply or throttle position based on the rotational speed of the engine. The governor consists of a rotating shaft driven by the engine, with two or more weighted arms ( fly balls ) attached to it.
As the engine speed increases, the centrifugal force on the flywheel also increases, causing them to move outward. This movement is transmitted to a linkage mechanism that adjusts the throttle or fuel supply. When the engine reaches the desired speed, the force exerted by the flywheel balances with the force exerted by a spring or weights, maintaining a stable speed.
If the engine speed decreases due to an increase in load, the flywheel move inward, reducing the throttle or fuel supply, and vice versa. This continuous adjustment helps to maintain a constant speed under varying load conditions, providing a more stable and controlled operation.
Inertia governors played a crucial role in early industrial machinery and were a significant advancement in the development of automated speed control systems. However, with the advent of modern electronic controls and more advanced engine technologies, their usage has diminished in favor of more efficient and precise speed control mechanisms.
Some types of Governer are defined as follows:-
( a ) Watt governor
The Watt governor, also known as the centrifugal governor, is a device used to regulate the speed of steam engines during the Industrial Revolution. It was invented by James Watt, a Scottish engineer and inventor, in the late 18th century.
The main purpose of the Watt governor was to maintain a relatively constant speed of the steam engine by controlling the flow of steam to the engine's cylinders. It achieved this by utilizing centrifugal force.
The governor consisted of two rotating balls or weights attached to a vertical spindle, which was connected to a throttle valve or a mechanism controlling the steam flow. As the speed of the engine increased, the centrifugal force acting on the balls would cause them to move outward, raising the throttle valve and reducing the steam flow.
Conversely, when the speed decreased, the balls would move inward, lowering the throttle valve and allowing more steam to flow.
The governor was an important innovation as it provided a self-regulating mechanism for steam engines, allowing them to maintain a more constant speed. This was crucial for many industrial applications that required consistent power output, such as textile mills and factories.
The Watt governor helped improve the efficiency and reliability of steam engines and played a significant role in the development of the Industrial Revolution.
( b ) Porter governor
The Porter governor, also known as the Porter-Porter governor, is a type of centrifugal governor used to regulate the speed of steam engines. It was invented by American engineer Robert Porter in the mid-19th century.
The governor consists of a pair of rotating balls or weights connected to a spindle. The spindle is driven by the engine and rotates at a speed proportional to the engine's speed. As the spindle rotates, the balls move outward due to centrifugal force.
The balls are connected to a central vertical lever, which controls the engine's throttle valve or fuel supply. When the balls move outward, the lever is pushed downward, reducing the throttle opening and limiting the fuel or steam flow to the engine. Conversely, when the balls move inward, the lever is lifted, increasing the throttle opening and allowing more fuel or steam to reach the engine.
The Porter governor operates based on the principle of negative feedback. As the engine speed increases, the balls move outward, reducing the fuel supply and slowing down the engine. If the engine speed decreases, the balls move inward, opening the throttle and increasing the fuel supply, thus speeding up the engine.
The Porter governor is a type of centrifugal governor and is commonly used in stationary steam engines to maintain a relatively constant speed. It is named after its inventor, Robert Porter, who improved upon the design of earlier governors and made significant contributions to the field of mechanical engineering.
( C ) Hartnell governor
The Hartnell governor is a type of centrifugal governor, which is a device used to regulate the speed of engines and machines. It was invented by James Hartnell in the 19th century.
The primary function of the Hartnell governor is to control the amount of fuel entering an engine in order to maintain a relatively constant speed, regardless of changes in the load. It achieves this by using centrifugal force generated by rotating weights.
The governor consists of two main components: the rotating balls or weights and the sleeve or spindle. The weights are attached to arms that are connected to the spindle. As the engine speed increases, the centrifugal force causes the weights to move outward, which in turn raises the sleeve or spindle. This movement controls the fuel supply to the engine.
The Hartnell governor operates based on a simple principle: when the engine speed increases, the centrifugal force acting on the weights increases, causing them to move outward.
As a result, the sleeve or spindle rises, reducing the fuel supply. When the engine speed decreases, the weights move inward, lowering the sleeve or spindle and increasing the fuel supply. This continuous adjustment helps maintain a relatively constant speed.
The Hartnell governor was widely used in various types of engines, such as steam engines and early internal combustion engines. It played a crucial role in ensuring the stability and control of these machines, particularly in industrial applications.
While it has been largely replaced by more advanced speed control systems in modern engines, the Hartnell governor remains an important part of engineering history and the development of control systems.
( d ) Hartung governor
The Hartung governor is a type of mechanical governor used in steam engines and other rotating machinery to regulate the speed of the engine. It was invented by Emil Hartung in the 19th century.
The governor consists of a rotating spindle that is driven by the engine and connected to a pair of pivoting weights. The weights are attached to the spindle by adjustable links and are free to move outward or inward as the spindle rotates. As the speed of the engine changes, centrifugal force causes the weights to move outward or inward, changing the position of the links.
The movement of the links is then transmitted to a mechanism that controls the engine's fuel supply or throttle position, thereby regulating the engine speed. When the engine speed increases, the weights move outward, causing the fuel supply or throttle to be reduced, and vice versa.
The Hartung governor is known for its simplicity and reliability, and it was widely used in various applications, including steam engines, where it helped maintain a constant rotational speed despite fluctuations in load or steam pressure.
However, with the advent of electronic and digital control systems, mechanical governors like the Hartung governor have been largely replaced by more advanced and precise control mechanisms.
( e ) Wilson - Hartnell governor
The Wilson - Hartnell governor, also known as the Hartnell governor or simply the centrifugal governor, is a type of mechanical governor used in steam engines and other rotating machinery to control the speed or rotational velocity. It was developed by James Hartnell and James Wilson in the mid-19th century.
The governor operates based on the principle of centrifugal force. It consists of a rotating spindle driven by the engine shaft, with two pivoting arms or balls attached to the spindle. These arms are connected to a vertical lever mechanism that regulates the flow of steam or fuel to the engine, controlling its speed.
As the engine speed increases, the centrifugal force acting on the balls causes them to move outward, away from the spindle. This movement is transmitted to the lever mechanism, which adjusts the throttle valve or fuel supply to decrease the steam or fuel input. This action slows down the engine.
Conversely, if the engine speed decreases, the balls move inward, reducing the centrifugal force and allowing the lever mechanism to increase the steam or fuel supply, thereby increasing the engine speed.
The Wilson - Hartnell governor provided a simple and effective method for regulating engine speed in applications where maintaining a constant speed was important, such as in steam engines powering industrial machinery or locomotives. It played a significant role in the development of the industrial revolution by enabling more precise control over the operation of steam engines and improving their efficiency and safety.
( f ) Pickering governor
The Pickering governor is a type of centrifugal governor, which is a device used to control the speed of engines or machines by regulating the flow of fuel or other inputs. It was developed by William Pickering in the 19th century.
The Pickering governor consists of a rotating spindle driven by the engine or machine being controlled. Attached to the spindle are two pendulum-like arms, each with a set of weights at the end. These weights are free to move outward due to centrifugal force as the spindle rotates.
When the engine or machine runs at a higher speed than desired, the centrifugal force causes the weights to move outward. This motion is transmitted to a mechanism that adjusts the fuel or input flow, reducing the speed. Conversely, if the speed drops below the desired level, the weights move inward, adjusting the flow to increase the speed.
The Pickering governor operates on the principle of negative feedback, where the output (speed) is monitored and used to adjust the input (fuel or other flow). By continuously sensing and adjusting the speed, the governor helps maintain a relatively constant speed for the engine or machine.
The Pickering governor was widely used in steam engines, particularly in the 19th and early 20th centuries. It played a crucial role in maintaining the speed and stability of these engines, enabling their efficient operation in various applications such as factories, locomotives, and ships.
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