What Is a Comparator?

Comparators are devices that compare two voltages or currents and output a digital signal indicating which is larger. The output value of the comparator indicates which of the inputs is greater or lesser.

A comparator compares the two inputs applied to it and produces the comparison as the output. It has two analog input terminals and one binary digital output.

A comparator is an exact tool that is used to compare the dimensions of a given workpiece component with the actual work standard. Different types of comparisons are available.

They are commonly used in devices that measure and digitize analog signals, such as successive-approximation ADCs and relaxation oscillators.

Types of Comparators

Based on the method of magnification, the comparators are classified as follows:

1. Mechanical Comparator
2. Mechanical-Optical Comparator
3. Reed Type Comparator
4. Electrical-Electronic Comparator
5. Pneumatic Comparator

#1. Mechanical Comparator

1. A mechanical comparator employs mechanical means to obtain magnification, for example, levers, gear systems, etc.
2. Its construction requires a high degree of skill and precision.
3. The magnification of a mechanical comparator varies from 250 to 1000.

#2. Mechanical-Optical Comparator

 

1. In mechanical, optical comparators, small displacements of the measuring plunger are first amplified by a mechanical system consisting of perforated levers.
2. The amplified mechanical movement is further enhanced by a simple optical system involving the projection of an image.
3. The general arrangement employed is such that the mechanical system causes an aircraft reflector to tilt about an axis, and the image of an index is projected onto a scale on an internal ground-glass screen.
4. Optical magnification provides a high level of measuring accuracy for lack of movable members and better wear resistance properties.

#3. Reed Type Comparator

1. The device used to measure the linear displacement of the spindle with the help of a reed mechanism is known as a reed-type mechanical comparator.
2. It is a device for increasing the low speed of the spindle.

Constructional details :

1. The reed mechanism is a frictionless device for increasing the low speed of the spindle.
2. It consists of a fixed block ‘A,’ which is rigidly fastened to the gauge head case.
3. The floating block ‘B’ carries the gauging axis.
4.  The floating block is also horizontally attached to the block defined by `C`
5. A vertical reed is attached to each block in which the upper ends are joined together.
6. These vertical reads are shown with the letter ‘D’ in fig.
7. A pointer is attached to this joint.

#4. Electrical-Electronic Comparator

 

1. These comparators depend on the Wheatstone bridge circuit for their operation. In d.c.
2. There is a change in the balance of electrical resistance in each arm of the circuit, the bridge—displacement of an armature relative to the arm under the action of the measuring rider.
3. Once the balance is deteriorated by the bridge, it is measured by a galvanometer. The rider is read in units of linear movement. This circuit is powered by a battery.
4. To bridge For equilibrium, the ratio of resistors in the two arms must be equal.
5.  If alternating current is applied to the bridge, the inductance and capacitance Weapons must also be accounted for along with resistance.
6. In actual measuring instruments, one induction head is made by a pair of coils in the measuring head of the instrument.
7. The armature creates differences in this type Induction of a pair of coil forming AC of one hand Bridge.
8. The arm holds Armature and Indic- Is dependent on tance in the Relative coil displacement of armature For the coil. Other refinements are As an electrical device AL method of zero adjustments and A.
9. Switch to change the magnification.
10. The amount of imbalance due to measles movement- Ing rider is shown and shown on a linear scale.
11.  Order magnification of x 30,000 Is possible with this system. Commonly used equipment is elected electricity.

#5. Pneumatic Comparator

 

1. A comparator is a device used to measure the amplitude of a given component by comparing it with the actual working standard.
2. Pneumatic means air is used for the magnification of measured measurements, as compared to air and pneumatic.
3. Pneumatic comparators operate on the principle that if an air jet is in close proximity with a surface, the flow of air from the jet is restricted, which changes the air pressure in the jet-supplying system.

FAQ: Comparators: Types, Functions, and Applications

What Is a Comparator?

A comparator is a device that compares two voltages or currents and outputs a digital signal indicating which one is larger. It has two analog input terminals and one binary digital output, showing which input is greater or lesser.

What Are the Primary Uses of Comparators?

Comparators are commonly used in devices that measure and digitize analog signals, such as successive-approximation ADCs and relaxation oscillators. They are also essential tools for comparing the dimensions of workpiece components against actual work standards.

What Are the Different Types of Comparators?

Comparators can be classified into several types based on the method of magnification:

1. Mechanical Comparator
2. Mechanical-Optical Comparator
3. Reed Type Comparator
4. Electrical-Electronic Comparator
5. Pneumatic Comparator

How Does a Mechanical Comparator Work?

A mechanical comparator uses mechanical means like levers and gear systems to obtain magnification. It requires high precision in construction, and its magnification can vary from 250 to 1000.

What Is Unique About Mechanical-Optical Comparators?

Mechanical-optical comparators amplify small displacements of the measuring plunger using a mechanical system, which is further enhanced by an optical system. This system provides high measuring accuracy due to the lack of movable parts and better wear resistance properties.

How Does a Reed Type Comparator Function?

A reed type comparator uses a reed mechanism to measure the linear displacement of the spindle. It involves a frictionless device that increases the low speed of the spindle, with a pointer attached to a joint of vertical reeds for measurement.

What Is the Principle Behind Electrical-Electronic Comparators?

Electrical-electronic comparators operate on the Wheatstone bridge circuit. Any change in the balance of electrical resistance in the circuit’s arms is measured by a galvanometer. These comparators can achieve high magnification, up to x 30,000.

How Do Pneumatic Comparators Work?

Pneumatic comparators use air for magnification. They operate on the principle that if an air jet is close to a surface, the flow of air is restricted, changing the air pressure in the jet-supplying system. This change is used to measure the amplitude of the component being compared.

What Are the Advantages of Using Comparators?

Comparators provide precise measurements and are essential for ensuring components meet specified standards. They offer high magnification, are versatile in application, and different types of comparators can be used for various measurement needs.

In What Industries Are Comparators Commonly Used?

Comparators are widely used in manufacturing and quality control industries to ensure that components meet exact specifications. They are also used in electronics, engineering, and automotive industries for precise measurements and comparisons.