What is the name for the motion that controls the heald shafts to create the shed for shuttle passage?
- Picking Motion
- Shedding Motion
- Beating-up Motion
- Letting-off Motion
Correct Answer: Shedding Motion
Correct Answer Explanation: The shedding motion is responsible for opening the warp threads to create the shed, allowing the shuttle to pass through and insert the weft yarn.
What type of loom typically uses a dobby mechanism to create more complex weaves?
- Tappet Loom
- Dobby Loom
- Jacquard Loom
- Shuttle Loom
Correct Answer: Dobby Loom
Correct Answer Explanation: Dobby looms use a dobby mechanism, which is more complex than a tappet loom and allows for more intricate weave patterns.
Which of these driving mechanisms is generally considered more efficient for looms weaving heavy wefted goods?
- Loose and Fast Pulleys
- Friction Drive
- Eccentric Driving
- Belt Drive
Correct Answer: Friction Drive
Correct Answer Explanation: Friction driving offers immediate power transmission, making it more efficient for heavy wefts as it reduces knock-offs and provides a smoother drive than loose and fast pulley systems.
What is the purpose of the brake on a loom?
- To control the speed of the loom
- To prevent the loom from over-running
- To adjust the tension of the warp yarns
- To guide the shuttle across the race
Correct Answer: To prevent the loom from over-running
Correct Answer Explanation: The brake helps to prevent the loom from over-running in situations like weft failure or warp protector activation. It acts as a safety mechanism to stop the loom quickly.
What type of loom uses a set of tappets to control the heald shafts and typically produces simpler weaves?
- Dobby Loom
- Jacquard Loom
- Tappet Loom
- Shuttle Loom
Correct Answer: Tappet Loom
Correct Answer Explanation: Tappet looms use tappets, which are simpler mechanisms compared to dobby or jacquard looms, limiting them to simpler weaves.
Which of these is a common fabric defect associated with improper shedding or picking motions?
- Broken Warp Threads
- Uneven Weft Density
- Fabric Wrinkles
- Loose Selvedges
Correct Answer: Uneven Weft Density
Correct Answer Explanation: Improper shedding or picking motions can lead to inconsistent weft density, resulting in areas of the fabric being too tight or too loose.
What type of driving motion is sometimes preferred for looms weaving heavy wefted goods, utilizing bevel and spur gears?
- Direct Driving
- Eccentric Driving
- Indirect Driving
- Friction Driving
Correct Answer: Indirect Driving
Correct Answer Explanation: Indirect driving motion, often involving bevel and spur gears, is sometimes favored for heavy wefted goods as it provides more power and control over the motion, especially during the beat-up phase.
What is the main function of the going part (or lay) of a loom?
- Controlling the shed for shuttle passage
- Driving the shuttle across the race
- Pushing the weft into place after each shuttle pass
- Regulating the tension of the warp yarns
Correct Answer: Pushing the weft into place after each shuttle pass
Correct Answer Explanation: The going part (or lay) of a loom is responsible for beating-up the weft, which means pushing the inserted weft yarn into place, creating a tight and stable fabric structure.
What is the formula for calculating the speed of shafts, drum size, and change wheels in a loom?
- D R = d r
- D + R = d + r
- D/R = d/r
- D – R = d – r
Correct Answer: D R = d r
Correct Answer Explanation: The formula D R = d r is used to calculate the speed of different shafts, drum sizes, and change wheels in loom configurations. It helps to determine the correct gear ratios and ensure proper synchronization of motions.
Which of these principles is NOT used in loom mechanisms to achieve complex motions?
- Spur and bevel gear gearing
- Ratchet wheel and pawl
- Worm and worm-wheel gearing
- Hydraulic pressure system
Correct Answer: Hydraulic pressure system
Correct Answer Explanation: While hydraulic systems are used in some modern machinery, they are not traditionally used in the core mechanisms of looms like tappet and dobby looms, which rely on mechanical gears, levers, and other components.
What is the name of the smooth surface on top of the lay that the shuttle travels across?
- Race
- Shed
- Batten
- Reed
Correct Answer: Race
Correct Answer Explanation: The race is a smooth, usually wood or steel, surface on top of the lay that provides a path for the shuttle to travel across during each weft insertion.
What is the minimum dwell time for healds in some looms, calculated as a fraction of a crankshaft revolution?
- 1/2
- 1/4
- 1/8
- 1/16
Correct Answer: 1/4
Correct Answer Explanation: In some loom designs, the minimum dwell time for healds, which is the time they remain in their lifted or depressed position, is calculated as 1/4 of a crankshaft revolution to ensure proper thread movement and prevent breakage.
Which type of tappet is limited to weaving fabrics with weaves complete on not more than six picks in a repeat?
- Barrel Tappet
- Sectional Tappet
- Bradford Tappet
- Jacquard Tappet
Correct Answer: Sectional Tappet
Correct Answer Explanation: Sectional tappets are typically limited to weaves with repeats of six picks or less due to their design and the way they control the heald shafts.
What is the maximum number of heald shafts that a dobby loom can typically accommodate?
- 16
- 24
- 36
- 48
Correct Answer: 48
Correct Answer Explanation: While 16, 24, and 36-shaft dobbies are more common, dobby looms can accommodate up to 48 heald shafts, allowing for complex weaves and intricate designs.
What is the primary function of the balance wheel in a loom?
- Regulating the tension of the warp yarns
- Providing a smooth path for the shuttle
- Assisting in overcoming variable resistance during crankshaft rotation
- Controlling the speed of the loom
Correct Answer: Assisting in overcoming variable resistance during crankshaft rotation
Correct Answer Explanation: The balance wheel acts as a flywheel, storing and releasing energy to smooth out the rotational motion of the crankshaft, especially when there are variations in resistance from the weaving process.
Which type of tappet is often fitted with 13 heald shafts and used for more complex weaves?
- Sectional Tappet
- Barrel Tappet
- Bradford Tappet
- Jacquard Tappet
Correct Answer: Bradford Tappet
Correct Answer Explanation: Bradford tappet looms are often fitted with 13 heald shafts, providing more flexibility for creating intricate weaves than other tappet types.
What is the name for the motion that regulates the tension of the warp yarns as the fabric is woven?
- Shedding Motion
- Letting-off Motion
- Picking Motion
- Beating-up Motion
Correct Answer: Letting-off Motion
Correct Answer Explanation: The letting-off motion controls the release of warp yarns from the warp beam, ensuring consistent tension and preventing the fabric from becoming too tight or too loose during weaving.
What is the typical timeframe for the operation of a warp protector stop motion, measured in degrees of crankshaft rotation?
- 10-15 degrees
- 20-25 degrees
- 30-35 degrees
- 40-45 degrees
Correct Answer: 10-15 degrees
Correct Answer Explanation: The warp protector stop motion typically operates within a short timeframe, usually around 10-15 degrees of crankshaft rotation, to quickly stop the loom if a warp thread breaks or becomes entangled.
What is the name of the motion that controls the take-up of woven fabric on the cloth beam?
- Letting-off Motion
- Picking Motion
- Beating-up Motion
- Setting-up Motion
Correct Answer: Setting-up Motion
Correct Answer Explanation: The setting-up motion controls the winding of the woven fabric onto the cloth beam, ensuring a smooth and consistent take-up of the finished fabric.
What is the name of the mechanism that is highly flexible, accommodating any weave regardless of interlacing order or the number of shafts lifted and depressed?
- Stocks and Bowls
- Kenyon’s Under-Motion
- Heald Pulleys
- Sectional Tappet
Correct Answer: Kenyon’s Under-Motion
Correct Answer Explanation: Kenyon’s under-motion is highly flexible and can be used for any weave, even complex ones with odd numbers of shafts and intricate interlacings, making it a versatile weaving mechanism.
Which of these is NOT a benefit of early shedding, where the shed is formed before the shuttle reaches the beat-up?
- Improved fabric cover
- Easier insertion of heavy wefts
- Reduced risk of shuttle flying out
- Reduced fabric tension
Correct Answer: Reduced fabric tension
Correct Answer Explanation: While early shedding offers several advantages, it does not necessarily lead to reduced fabric tension. In fact, it can sometimes increase tension depending on how it is implemented.
What type of loom is specifically designed for weaving fabrics with elaborate and intricate patterns?
- Tappet Loom
- Dobby Loom
- Jacquard Loom
- Shuttle Loom
Correct Answer: Jacquard Loom
Correct Answer Explanation: Jacquard looms, equipped with a complex jacquard machine, are capable of weaving fabrics with highly intricate patterns, far exceeding the capabilities of tappet or dobby looms.
What is the name for the motion that drives the shuttle across the race?
- Picking Motion
- Shedding Motion
- Beating-up Motion
- Letting-off Motion
Correct Answer: Picking Motion
Correct Answer Explanation: The picking motion is responsible for driving the shuttle across the race, carrying the weft yarn and inserting it into the shed created by the warp threads.
What is the name for the motion that pushes the weft into place, controlled by the going part (lay) of the loom?
- Shedding Motion
- Picking Motion
- Beating-up Motion
- Letting-off Motion
Correct Answer: Beating-up Motion
Correct Answer Explanation: The beating-up motion, controlled by the going part or lay, pushes the inserted weft yarn into place, creating a tight and stable fabric structure.
What is the name of the mechanism that is typically used for weaves with an even number of threads, where the movements of the threads are reversals?
- Stocks and Bowls
- Kenyon’s Under-Motion
- Heald Pulleys
- Sectional Tappet
Correct Answer: Heald Pulleys
Correct Answer Explanation: Heald pulleys are often used for weaves with an even number of threads, where the movements of the threads are reversals, allowing for efficient thread control and shed formation.
Which of these is NOT a common type of brake motion used in looms?
- Weft stop motion
- Warp protector motion
- Knock-off motion
- Hydraulic brake motion
Correct Answer: Hydraulic brake motion
Correct Answer Explanation: While hydraulic systems are becoming more common in industrial settings, they are not traditionally used for brake motions in looms like tappet and dobby looms, which typically rely on mechanical brakes.
Which of these factors does NOT influence the eccentricity of the going part in a loom?
- Crank size
- Connector arm length
- Crankshaft position
- Shuttle weight
Correct Answer: Shuttle weight
Correct Answer Explanation: The eccentricity of the going part, which refers to its off-center movement, is primarily determined by the crank size, connector arm length, and crankshaft position. The shuttle weight does not directly influence the going part’s eccentricity.
What is the name for the type of loom that uses a series of tappets to control the heald shafts, often used for simpler weaves?
- Dobby Loom
- Jacquard Loom
- Tappet Loom
- Shuttle Loom
Correct Answer: Tappet Loom
Correct Answer Explanation: Tappet looms utilize a series of tappets to control the heald shafts, allowing for simpler weaves compared to dobby or jacquard looms.
What is the name for the mechanism that uses a series of stepped pulleys to compensate for slackening and tightening of heald cords during shed formation?
- Kenyon’s Under-Motion
- Stocks and Bowls
- Heald Pulleys
- Sectional Tappet
Correct Answer: Stocks and Bowls
Correct Answer Explanation: Stocks and Bowls are mechanisms that use stepped pulleys to adjust the tension of heald cords, ensuring proper thread movement and shed formation during weaving.
What is the name for the condition where the reed is not positioned correctly at the beat-up, leading to uneven fabric density and potential defects?
- Reed misalignment
- Reed slippage
- Reed breakage
- Reed wear
Correct Answer: Reed misalignment
Correct Answer Explanation: Reed misalignment occurs when the reed, which separates the warp threads and guides the shuttle, is not properly positioned during the beat-up motion, resulting in uneven fabric density and potential defects.
What is the name for the condition where the warp threads offer different levels of resistance to the beat-up motion, depending on the weave design and shedding motion used?
- Warp tension
- Warp slippage
- Warp resistance
- Warp breakage
Correct Answer: Warp resistance
Correct Answer Explanation: Warp resistance refers to the different levels of resistance offered by the warp threads to the beat-up motion, which can vary depending on the weave design and the shedding motion used.
What is the name for the method of creating a trough-like shape in the shed before the shuttle reaches the beat-up, often used to prevent reed marks and improve fabric cover?
- Troughing the shed
- Early shedding
- Late shedding
- Beat-up control
Correct Answer: Troughing the shed
Correct Answer Explanation: Troughing the shed refers to the method of creating a trough-like shape in the shed before the shuttle reaches the beat-up, which can prevent reed marks, improve fabric cover, and enhance the overall appearance of the woven fabric.
What is the typical range of heald shafts that a tappet loom can accommodate, depending on the type of weave?
- 2-12 heald shafts
- 12-24 heald shafts
- 24-36 heald shafts
- 36-48 heald shafts
Correct Answer: 2-12 heald shafts
Correct Answer Explanation: Tappet looms typically accommodate between 2 and 12 heald shafts, which are used to control the warp threads and create the shed for shuttle passage. The exact number depends on the complexity of the weave being produced.
What is the name of the process of drawing the outline of a tappet for a specific weave, which is used to design the tappet’s contour and ensure proper shed formation?
- Tappet design
- Tappet construction
- Tappet setting
- Tappet adjustment
Correct Answer: Tappet construction
Correct Answer Explanation: Tappet construction is the process of designing and creating the outline of a tappet for a specific weave. It involves determining the tappet’s shape and contours to ensure that it properly controls the heald shafts and forms the desired shed for shuttle passage.
What is the name for the type of weave where the same number of shafts are lifted and depressed on each pick, allowing for the use of stocks and bowls for thread control?
- Even weave
- Odd weave
- Interlaced weave
- Reverse weave
Correct Answer: Even weave
Correct Answer Explanation: Even weaves are characterized by an equal number of shafts being lifted and depressed on each pick, allowing for the use of stocks and bowls to control the tension of the heald cords and ensure proper shed formation.
Which of these is NOT a typical weave that can be produced on a tappet loom?
- 2×2 Twill
- Plain weave
- Satin weave
- Damask weave
Correct Answer: Damask weave
Correct Answer Explanation: While tappet looms can produce a variety of weaves, including plain weave and 2×2 twill, they are generally not suitable for more complex weaves like damask, which requires more intricate pattern control and often necessitates the use of a dobby or jacquard loom.
What is the name of the motion that is timed to ensure that the boxes are fully changed before the shuttle is picked, preventing weft yarn misalignment?
- Box motion
- Shedding motion
- Picking motion
- Beating-up motion
Correct Answer: Box motion
Correct Answer Explanation: The box motion is responsible for changing the weft yarn boxes on a loom, ensuring that the correct weft yarn is available for the shuttle to pick. This motion must be carefully timed to ensure that the boxes are fully changed before the shuttle is picked, preventing weft yarn misalignment and potential fabric defects.
What is the name for the type of motion that controls the movement of the heald shafts, determining the timing of the shed and the nature of the motion imparted to the threads?
- Tappet motion
- Dobby motion
- Jacquard motion
- Shuttle motion
Correct Answer: Tappet motion
Correct Answer Explanation: The tappet motion, controlled by a series of tappets, is responsible for the movement of the heald shafts, determining the timing of the shed and the nature of the motion imparted to the threads. This motion is essential for creating the desired shed and ensuring proper thread movement during weaving.
Which of these is NOT a factor that can contribute to shuttle flying out of the race?
- Defects in the race
- Improper shuttle tension
- Excessive loom speed
- Incorrect tappet setting
Correct Answer: Incorrect tappet setting
Correct Answer Explanation: While incorrect tappet settings can lead to other weaving problems, they are not directly related to the shuttle flying out of the race. Shuttle flying out is usually caused by defects in the race, improper shuttle tension, or excessive loom speed.
What is the name for the type of weave where the threads interlace in a diagonal pattern, creating a distinctive texture?
- Plain weave
- Twill weave
- Satin weave
- Damask weave
Correct Answer: Twill weave
Correct Answer Explanation: Twill weave is characterized by its diagonal interlacing pattern, which creates a distinct texture and often results in a diagonal rib on the fabric’s surface.
What is the name of the type of weave where the weft yarn floats over a large number of warp threads, creating a smooth and lustrous surface?
- Plain weave
- Twill weave
- Satin weave
- Damask weave
Correct Answer: Satin weave
Correct Answer Explanation: Satin weave is characterized by its long weft yarn floats over several warp threads, creating a smooth and lustrous surface. This weave is often used for fabrics like satin and charmeuse.
What is the name of the type of weave where the pattern is created by using different colored yarns and interlacing them in a complex design?
- Plain weave
- Twill weave
- Satin weave
- Damask weave
Correct Answer: Damask weave
Correct Answer Explanation: Damask weave uses different colored yarns and interlaces them in a complex design to create intricate patterns on the fabric surface. This weave is often used for tablecloths, napkins, and other decorative textiles.
Which of these is NOT a common factor that can influence the efficiency of a loom?
- Loom maintenance
- Driving mechanism
- Yarn preparation
- Fabric design
Correct Answer: Fabric design
Correct Answer Explanation: While fabric design can influence the complexity of the weaving process and the time required to produce a given length of fabric, it does not directly impact the efficiency of the loom itself. Loom efficiency is primarily determined by factors such as maintenance, driving mechanism, and yarn preparation.
What is the name of the process of preparing the warp yarns for weaving, which involves winding them onto the warp beam and ensuring proper tension?
- Warp winding
- Warp sizing
- Warp preparation
- Warp dressing
Correct Answer: Warp preparation
Correct Answer Explanation: Warp preparation involves a series of steps, including winding the warp yarns onto the warp beam, ensuring proper tension, and sometimes applying sizing to strengthen and protect the yarns. This process is crucial for achieving smooth and efficient weaving.
What is the name of the type of motion that is typically used for weaving fabrics with an odd number of shafts, where the same number of shafts are lifted and depressed on each pick?
- Stocks and Bowls
- Kenyon’s Under-Motion
- Heald Pulleys
- Sectional Tappet
Correct Answer: Stocks and Bowls
Correct Answer Explanation: Stocks and Bowls are mechanisms that are typically used for weaving fabrics with an odd number of shafts, where the same number of shafts are lifted and depressed on each pick. This allows for proper thread control and shed formation, ensuring smooth and efficient weaving.
What is the name of the type of weave where the threads interlace in a simple over-and-under pattern, creating a basic and durable fabric?
- Twill weave
- Satin weave
- Plain weave
- Damask weave
Correct Answer: Plain weave
Correct Answer Explanation: Plain weave is the most basic type of weave, where the threads interlace in a simple over-and-under pattern. This weave is known for its durability and is commonly used for fabrics such as cotton and linen.
Which of these is NOT a typical material used for the race of a loom?
- Wood
- Steel
- Plastic
- Leather
Correct Answer: Leather
Correct Answer Explanation: While leather was historically used in some weaving equipment, it is not a typical material for the race of a loom. Wood and steel are the most common materials for the race, providing a smooth and durable surface for the shuttle to travel across.
What is the name of the part of the loom that is responsible for beating-up the weft yarn and guiding the shuttle during the weaving process?
- Going part (or lay)
- Shed
- Batten
- Reed
Correct Answer: Going part (or lay)
Correct Answer Explanation: The going part or lay of the loom is a critical component that is responsible for beating-up the weft yarn, which means pushing it into place after each shuttle pass, and guiding the shuttle during the weaving process.
What is the name of the process of ensuring that the loom is in proper working order and that all the parts are functioning correctly?
- Loom maintenance
- Loom repair
- Loom adjustment
- Loom lubrication
Correct Answer: Loom maintenance
Correct Answer Explanation: Loom maintenance involves a series of regular checks and adjustments to ensure that the loom is in proper working order and that all the parts are functioning correctly. This helps to prevent breakdowns, improve weaving efficiency, and ensure the production of high-quality fabric.
Which of these is NOT a factor that can influence the timing of the box motion in a loom?
- Loom speed
- Weft yarn type
- Shuttle speed
- Fabric design
Correct Answer: Fabric design
Correct Answer Explanation: While fabric design can influence the overall weaving process, it does not directly impact the timing of the box motion. The timing of the box motion is primarily determined by factors such as loom speed, weft yarn type, and shuttle speed.
What is the name of the process of ensuring that the tappets are properly set to create the desired shed for shuttle passage?
- Tappet design
- Tappet construction
- Tappet setting
- Tappet adjustment
Correct Answer: Tappet setting
Correct Answer Explanation: Tappet setting involves adjusting the position of the tappets on the loom to ensure that they create the desired shed for shuttle passage. This is a critical step in the loom setup process and must be done carefully to achieve proper thread movement and prevent weaving defects.
What is the name for the condition where the warp threads are not properly aligned, leading to uneven fabric density and potential defects?
- Warp tension
- Warp slippage
- Warp resistance
- Warp misalignment
Correct Answer: Warp misalignment
Correct Answer Explanation: Warp misalignment occurs when the warp threads are not properly aligned, leading to uneven fabric density and potential defects. This can be caused by factors such as improper warp preparation or loom setup.
What is the name of the process of adjusting the position of the tappets on the loom to ensure that they create the desired shed for shuttle passage?
- Tappet design
- Tappet construction
- Tappet setting
- Tappet adjustment
Correct Answer: Tappet adjustment
Correct Answer Explanation: Tappet adjustment involves adjusting the position of the tappets on the loom to ensure that they create the desired shed for shuttle passage. This is a critical step in the loom setup process and must be done carefully to achieve proper thread movement and prevent weaving defects.
What is the name for the condition where the shuttle is not moving smoothly across the race, leading to potential defects and fabric damage?
- Shuttle misalignment
- Shuttle slippage
- Shuttle wear
- Shuttle jamming
Correct Answer: Shuttle misalignment
Correct Answer Explanation: Shuttle misalignment occurs when the shuttle is not properly aligned in the race, leading to uneven fabric density, potential defects, and even fabric damage. This can be caused by factors such as improper shuttle tension, worn race components, or incorrect loom setup.