What is mount motor?

A mount motor can be termed as an engine mount. Mount motors are essential parts of machines and establish a connection between an engine and chassis. They prevent the engine and chassis from getting damaged and also help to stabilize the engine.

Their main objective is to absorb and resist shocks, and also to reduce noise and vibrations. Mount motors are also called motor mounts.

Parts of motor mounts

• Sleeve bushing
• Connection bolts
• Rubber body
• Vacuum actuators
• Hub and motor adapters
• Gears
• Tube and covers
• Sensors, and many more

Applications of motor mounts

There are several applications of mount motors, which are listed below:

• Power generating devices
• Air compressors
• Vehicles like cars, trucks, etc.
• Mass transportation
• Industry usage
• Construction
• Agriculture
• Marine
• Forestry, and many more

Engine mount materials

Several types of raw materials are used to produce motor mounts, some of which are discussed below.

• Rubber mount materials like natural rubber, neoprene, ethylene, propylene, diene monomer, silicon rubber, etc.
• Metal substrates like brass, aluminum, iron, stainless steel, etc.

Rubber and metal bonding provides the sturdiest and best design of the engines.

What are the types of motor mount?

There are various types of motor mounts, some of which are listed below:

• Hydraulic motor mounts
• Electronic motor mounts
• Rigid motor mounts
• Solid rubber motor mounts
• Rigid motor mounts
• Polyurethane motor mounts
• Metal motor mounts
• Resilient motor mounts
• Face motor mounts

Let's look in detail at some of the motor mounts mentioned above.

Hydraulic motor mounts

These motor mounts are generally filled with fluids. They are manufactured or designed to absorb the shock and vibrations of the system's engine so that the vibrations do not reach the chassis position. The essential use of motor mounts is to generate high or low frequencies of vibrations. Hydraulic motor mounts are usually preferred in automobiles, vehicles, construction, and other industries due to their minimum noise levels. Further, they can be employed to provide better performance on more extensive condition ranges.

The hydraulic motor mounts is shown as,

Electronic motor mounts

Electronic motor mounts are designed for the variation of stiffness and motor mount damping behavior. These mounts help to reduce vibrations, shocks, and noise levels. They also manage the load with their speed.

Electronic motor mounts are processed and monitored with the help of the control system and sensors. The vibrations of various engines can be reduced by control systems like vacuum actuators, etc.

The electronic motor mount is shown as,

Rigid motor mounts

Rigid motor mounts are attached to a system's frame and fastened with bolts. They are sometimes welded permanently at a particular place on the system, and are comparatively smaller in size to other motor mounts.

Rigid motor mounts provide accurate alignment with different mechanisms. However, they can be broken by the shocks and vibrations due to overloading or heavy-duty operations.

The rigid motor mount is shown as,

Solid rubber motor mounts

These mounts are also called transmission mounts. They are made of solid rubber and bolted along with the engine chassis system. Solid rubber motor mounts are more flexible as compared to other mounts. They are also more suitable for the absorption of shocks and vibrations.

Rubber motor mounts are found in vehicles like trucks, cars, and many more. They are positioned at one location to hold the engine at one place, and reduce the noise level at a comparatively lower cost than other motor mounts. However, due to improper mounting, they may crack. Heavy-duty operations are not suitable as they produce extra movement, so the performance is affected.

The benefits of rubber motor mounts are:n good damping, energy absorption, noise absorption, heat dissipation, longer lifespan, and resistance to ozone, oil, and other fluids like water.

Molding processes of a rubber motor mount

There are three main ways to mold the rubber parts, which are listed below:

• Injection molding
• Compression molding
• Transfer molding

Rubber to metal molding in mount motors

The steps used to mold rubber to metal are listed below:

• Choosing elastomers
• Preparing metal substrate
• Priming of both parts (rubber and metal)
• Applying adhesive materials on metal
• Molding and bonding rubber and metal parts
• Testing and inspecting bond strengths

Polyurethane motor mounts

These motor mounts have longer lives as compared to rubber mounts. Their performance and benefits are higher than both their solid steel and rubber counterparts.

However, this makes them relatively costlier. Also, these motor mounts have low heat-resistant properties. Further, the bond between polyurethane and stainless steel is tough to achieve.

The polyurethane motor mount is shown as,

Common Mistakes

• It is a misconception that for stiffness variation, rigid mount motors are employed. Rather, electronic motor mounts are designed for the various stiffness criteria.
• It is a misconception that sensors play an essential role in all types of motor mounts, though they are employed majorly in electronic motor mounts.
• Hydraulic motor mounts do not provide better alignment with other machine parts than rigid motors.
• Polyurethane motor mounts are not smaller in size as compared to rigid mounts.
• Hydraulic motor mounts are not more flexible than other motor mounts; however, solid rubber motor mounts are highly flexible.

Context and Applications

The topic of mount motor is studied in many technical and professional, graduate, postgraduate, and doctorate-level courses, among others. For example:

• Bachelor of Technology in Mechanical Engineering
• Bachelor of Technology in Electrical Engineering
• Bachelor of Technology in Electronics Engineering
• Master of Technology in Mechanical Engineering
• Master of Technology in Electrical Engineering
• Doctor of Philosophy in Electrical Engineering

Related Concepts

• Mount motors overview
• Motor mounts
• Types of engine mounts
• Applications of engine mounts
• Engine mount materials
• Rubber engine mounts

Practice Problems

Q1: Which of the following motor mounts is suitable for heavy shock loads?

(a) Center-bonded mount

(b) Hydraulic motor mount

(c) Conical mount

(d) Polyurethane motor mount

Correct option: (a)

Explanation: Center-bonded mounts have high load-carrying capacities and can withstand various shock loads. They act as a shock protector.

Q2: Which of the following mount motors uses fluids?

(a) Electronic motor mount

(b) Hydraulic motor mount

(c) Rigid motor mount

(d) Solid rubber motor mount

Correct option: (b)

Explanation: Hydraulic motor mounts use fluids like glycol or water. These mounts are generally made of rubber, and fluids are filled at the center.

Q3: Which of the following motor mounts is long-lasting?

(a) Center-bonded mount

(b) Two-piece mount

(c) Polyurethane motor mount

(d) Rigid mount

Correct option: (c)

Explanation: Polyurethane motor mounts have longer lives during the operation. They live 3-4 times longer than rubber mounts and, unlike the latter, usually do not dry and crack.

Q4: Which of the following is not a feature of solid rubber motor mounts?

(a) Good damping

(b) Less lifetime

(c) More stable

(d) Oil, water-resistant

Correct option: (b)

Explanation: Solid rubber motor mounts have good damping. They are highly stable and are resistant to oil and water. They also have a longer life.

Q5: Which of the following is not a feature of a hydraulic motor mount?

(a) More complex

(b) Hydraulic fluids 

(c) Vibration resistance

(d) Highly flexible than rubber mounts

Correct option: (d)

Explanation: Hydraulic motor mounts are more complex in construction. They use hydraulic fluids, are resistant to vibration, and are less flexible than rubber mounts.