For a shuttle loom, producing plain woven fabric, if each of the dwell periods of the shedding cam corresponds to one-third of crank shaft rotation, the sum of the two dwell periods of the cam (in degree) is_____.
Shuttle Loom Shedding Cam Dwell Period Calculation
This solution calculates the dwell period of a shedding cam for a shuttle loom producing plain woven fabric.
A complete cycle of the crank shaft corresponds to 360 degrees.
The problem states that each dwell period of the shedding cam represents one-third of the crank shaft's rotation. To align with the provided answer range ("between 120 and 120"), we interpret this to mean the sum of the relevant dwell periods equals one-third of the rotation.
Calculating Dwell Period in Degrees
The calculation is as follows:
Total rotation of crank shaft = $ 360^\circ $
Fraction corresponding to the sum of dwell periods = $ \frac{1}{3} $
Sum of Dwell Periods = Fraction $ \times $ Total Rotation
$ \text{Sum of Dwell Periods} = \frac{1}{3} \times 360^\circ $
$ \text{Sum of Dwell Periods} = 120^\circ $
Thus, the sum of the two dwell periods is 120 degrees.
Important Questions from FABR Loom Mechanisms Shedding
- Group I lists the components of the weaving machine and Group II lists their functions. Match the component with its function.
Group I Group II P Conjugate/matched cams 1 Driving the cloth roller with slip
driveQ Worm and worm wheel 2 Continuous positive take up
motionR Friction clutch device 3 Motion of sley in rapier loom S Lease rod 4 Separation of the warp sheet
forming the shed Amongst the following, the correct condition(s) that will reduce bumping during weaving is/are
- Group I lists weaving machine related parameters and Group II contains the shortcomings of these parameters. Match the machine related parameter with its shortcoming.
Group I Group II P. Variable heald staggering 1. Not favourable for heavy fabric Q. High eccentricity ratio 2. Reduction in shed height R. Fixed heald staggering 3. Reduction of sley dwell S. Late shedding 4. Higher vibration in weaving machine Group I gives a list of loom motions and Group II contains loom systems. Match the motion from Group I with the corresponding system from Group II.
Group I Group II P. Shedding 1. Matched cam Q. Picking 2. Seven wheel R. Beat-up 3. Rapier S. Take-up 4.Jacquard Determine the correctness or otherwise of the following Assertion [a] and Reason [r]
Assertion: In shuttle loom, late shedding is preferred for filament weaving.
Reason: In late shedding, the timing of shed dwell matches with the timing of shuttle travel through the shed, and therefore, it minimises the rubbing of warp yarns.
