Week 10- Assembly Workbench

Objective: To create quick return mechanism and CV joint parts in part workbench or generative work bench and assemble them
following guidelines

QUICK RETURN MECHANISM - A quick return mechanism is an apparatus to produce a reciprocating motion in which the time taken for travel in return stroke is less than in the forward stroke. It is driven by a circular motion source (typically a motor of some sort) and uses a system of links with three turning pairs and a sliding pair.
There are three types of Quick return mechanism:

• Whitworth Quick Return mechanism. - Here the rotary motion is converted into the oscillatory motion. In this mechanism, the bull gear is used and It has a crank pinion. The sliding block slides over the Crankpin and slides inside the slot of a crank plate and The connecting rod connects the pin at one end and ram at the other end.

  The electric motor shaft drives the pinion and rotates the gear. Now the bull gear is also rotating along with the crankpin and the sliding block slides on the slot provided on the crank plate. So this process makes the ram move up and down by the connecting rod.

• Crank and Slotted Link Mechanism - This mechanism was invented by Whitworth in the 1800s. The mechanism consists of a slider, crank, fixed link, slotted lever, connecting rod and ram.The crank is connected with the slider and fixed link. When the cranks start rotating the connecting rod pushes forward and backwards the ram.Here the motion is being converted into linear motion from rotary motion.The crank and slotted link mechanism are widely used in shaping machines like slotter, shaper Machine for producing flat surfaces on the workpiece. The return stroke is much faster then the forward stroke in this mechanism.

• Hydraulic Drive - In the hydraulic drive, there is a piston inside the hydraulic cylinder that reciprocates. The piston rod is connected between ram and piston. Therefore ram reciprocates with the piston.

  In the diagram, you can see there are two entries at the end of the cylinder. And below a control valve is attached which has four passes.

Procedure of creating parts:

1. First create all parts of CV joints and QRM with help of drawings provided

2. All parts to be created separately in part work bench

3. After creating all parts individualy we assemble them together in single product in assembly workbench

4. Using constriants we assemble all parts together and create CV joint and QRM.

CV JOINT - Constant-velocity joints (also known as homokinetic or CV joints) allow a drive shaft to transmit power through a variable angle, at
constant rotational speed, without an appreciable increase in friction or play.They are mainly used in front wheel drive vehicles. Modern rear wheel drive cars with independent rear suspension typically use CV joints at the ends of the rear axle halfshafts and
increasingly use them on the drive shaft.Function

• Besides just holding the drive shaft in place, the CV joints also transfer power to the wheels from the transmission.
• Basically, they ensure that when you press on the gas, your wheels will turn. If the CV joint is not working properly, it may affect the way your vehicle
  handles.
• Often you will hear a popping or a clunk sound when shifting, which indicates something is wrong.
• If the joint breaks, it can stop the car from moving and can cause severe damage, making it essential component in your vehicle that needs to be kept in good condition.

Procedure of creating parts:

1. First create all parts of CV joints and QRM with help of drawings provided

2. All parts to be created separately in part work bench

3. After creating all parts individualy we assemble them together in single product in assembly workbench

4. Using constriants we assemble all parts together and create CV joint and QRM.

CONCLUSION-

All the parts are created in part workbench and assemble is created in assembly workbench successfully. From this challenge we know how to create assembly and assembly workbench all command, like existing component, new part, assembly constraint etc.