Different Types of Sewing Machine Belts
A belt is a loop of flexible material used to link two or more rotating shafts mechanically. Belts may be used as a source of motion, to power efficiently, or to track relative movement. Belts are looped over pulleys. In a two pulley system, the belt can either drive the pulleys in the same direction, or the belt may be crossed so that the direction of the shafts is opposite. As a source of motion, a conveyor belt is one application where the belt is adapted to continually carry a load between two points.
Belts are the cheapest utility for power transmission between shafts that may not be axially aligned. Power transmission is achieved by specially designed belts and pulleys.
Pros and cons
Belt drive, moreover, is simple, inexpensive, and does not require axially aligned shafts. It helps protect the machinery from overload and jam, and it isolates noise and vibration. Load fluctuations are shock-absorbed (cushioned). They need no lubrication and require minimal maintenance. They have high efficiency (90-98%, usually 95%), high tolerance for misalignment, and are inexpensive if the shafts are far apart. Clutch action is activated by releasing belt tension. Different speeds can be obtained by step or tapered pulleys.
The angular-velocity ratio may not be constant or equal to that of the pulley diameters, due to slip and stretch. However, this problem has been largely solved by the use of toothed belts. Adjustment of center distance or addition of an idler pulley is crucial to compensate for wear and stretch.
Following are the various types of Belts that are widely used
Flat Belt
The drive belt: used to transfer power from the engine’s flywheel. Here shown driving a threshing machine.
Flat belts were used early inline shafting to transmit power in factories. It is a simple system of power transmission that was well suited for its day. It delivered high power for high speeds (500 hp for 10,000 ft/min), in cases of wide belts and large pulleys. These drives are bulky, requiring high tension leading to high loads, so vee belts have mainly replaced the flat belts except when high speed is needed to overpower.
Round Belts
Round belts are circular cross-section belts designed to run in a pulley with a circular (or near-circular) groove. They are for use in low torque situations and may be purchased in various lengths or cut to length and joined, either by a staple, gluing, or welding (in a few cases).
Early sewing machines utilized a leather belt, joined either by a metal staple or glued, to a great effect.
Vee Belts
Vee belts (also known as V-belt or wedge rope) solved the slippage and alignment problem. It is now the basic belt for power transmission. They provide the best combination of traction, speed of movement, a load of the bearings, and long service life. They are generally endless, and their general cross-section shape is trapezoidal. The “V” shape of the belt tracks in a mating groove in the pulley (or sheave), with the result, that the belt cannot slip off.
The belt also tends to wedge into the groove as the load increases — the greater the load, the greater the wedging action — improving torque transmission and making the V-belt an effective solution, needing less width and tension than flat belts. V-belts need larger pulleys for their larger thickness than flat belts.
They can be supplied at various fixed lengths or as a segmented section, where the segments are linked (spliced) to form a belt of the required length. For high power requirements, two or more vee belts can be joined side by side in an arrangement called a multi-V, running on matching multi-groove sheaves. This is known as Multi-V belt drive (or sometimes classical V-belt drive).
Multi-Groove Belts
A multi-groove or Poly groove belt is made up of usually 5 or 6 “V” shapes alongside each other. This gives a thinner belt for the same drive surface, thus is more flexible, although often wider. The added flexibility offers improved efficiency, as less energy is wasted in the internal friction of continually bending the belt.
In practice, this gain of efficiency is overshadowed by the reduced heating effect on the belt, as a cooler-running belt lasts longer in service. A further advantage of the poly groove belt, and the reason they have become so popular, stems from the ability to be run over pulleys on the ungrooved back of the belt. Although this is sometimes done with vee belts and a single idler pulley for tensioning, a poly groove belt may be wrapped around a pulley on its back tightly enough to change its direction, or even to provide a light driving force.
Timing Belts
Timing belts are positive transfer belts and can track relative movement. These belts have teeth that fit into a matching toothed pulley. When correctly tensioned, they have no slippage, run at a constant speed, and are often used to transfer direct motion for indexing or timing purposes (hence their name). They are often used in lieu of chains or gears, so there is less noise and a lubrication bath is not necessary.
Camshafts of automobiles, miniature timing systems, and stepper motors often utilize these belts.
Timing belts need the least tension of all belts and are among the most efficient. They can bear up to 200 hp (150 kW) at speeds of 16,000 ft/min. Timing belts with a helical offset tooth design are available. The helical offset tooth design forms a chevron pattern and causes the teeth to engage progressively. The chevron pattern design is self-aligning. The chevron pattern design does not make the noise that some timing belts make at idiosyncratic speeds, and is more efficient at transferring power (up to 98%).
Disadvantages include a relatively high purchase cost, the need for specially fabricated toothed pulleys, less protection from overloading and jamming, and the lack of clutch action.
Introduction To Motors
A motor is a machine designed to convert energy into useful mechanical motion. Various types of motors are available in the market, but the Sewing industry mostly uses electric motors. An electric motor uses electrical energy to produce mechanical energy, usually through the interaction of magnetic fields and current-carrying conductors.
Electric Motors can be classified into two categories:
- AC Motors
- DC Motors
AC motors are mostly used for industrial Machinery.AC motors are also available in various categories.AC induction motor is the most common technology used in the Garment industry.
Electrical Motors used on Sewing Machines
A/c induction motors
An A/C MOTOR is used with the following drives to operate the sewing machine
- Clutch (For clutch Motor)
- SERVO (For Servo Motor)
- Direct Drive
We shall discuss the motors which are used vitally in the Sewing machines.
Clutch Motor
A clutch is a mechanical device that provides for the transmission of power from one component (the driving member) to another (the driven member). Clutches are useful in devices that have two rotating shafts. In these devices, one of the shafts is typically driven by a motor or pulley, and the other shaft drives another device. The clutch connects the two shafts so that they can be locked together and spins at the same speed. The same principle is used in the industrial sewing machine also.
Servo motor
Servo is an automatic device that uses error sensing negative feedback to correct the performance of a mechanism. The term correctly applies only to systems where the feedback or error-correction signals help control mechanical position or other parameters. Servo motor control system will replace the traditional electronic sewing machine motor control and drive system to become a mainstream technology. More and more extensive use of servo motor control systems by garment processing enterprises leads to cost-saving, maintenance-free, low noise, and replaces the traditional electronic motor control system. It becomes a sewing machine drive system of the mainstream.
Main Features of Servo Motor
- Low noise, low vibration, and low power
- Linkable to
- Multi- Positioning
- Switching power supply system (160V ~ AC).
- Powerful parameter system, easy adjustment and
Servo motor advantages
- Energy-saving & environmental protection
- Saving more than 80%
- Saving manpower by 20%
- Small size, simple operation, easy maintenance, beautiful appearance
- Long life
- Starts, braking action smooth, little vibration
Comparison Of Servo and Clutch Motor
| More features | Energy-saving servo motor | Clutch Motor |
|---|---|---|
| Exterior | Excellent, full of mechatronic design concepts | Decentralized structure, large pet |
| Labor intensity | Low. Operation simple and convenient, intelligent, operator fatigue is not easy |
High |
| Efficiency | High. Output increase, the corresponding reduction product processing fees | Low |
| Vibration | Low. Longer machine life, improve the quality of work improving the environment | Large |
| Noise | Low. Longer machine life, improve the working Environment |
Low. Longer machine life, improve the working Environment |
| Service | Low. Brushless servo motor, maintenance-free | Clutch Replacement |
| Energy | Once every province, electricity (98% of non-running Power, running power 26%) | Full operation |
| Network configuration |
Small. Start current, low total power consumption | Large |
| saving | Saving can be recovered within a year, consolidated return on investment for 6 months | High cost |
Direct Drive
A Direct drive mechanism is one that takes the power from a motor without any reductions (such as a gearbox, chain, and belt).
Advantages
- Increased efficiency: The power is not wasted in friction (from the belt, chain, etc, and especially, gearboxes).
- Reduced noise: Being a simpler device, a direct-drive mechanism has fewer parts that could vibrate, and the overall noise emission of the system is usually
- Longer lifetime: Having fewer moving parts also means having fewer parts prone to failure. Failures in other systems are usually produced by the aging of the component (such as a stretched belt), or stress.
- No maintenance is required for lubrication
You have said it all what I marveled about is the blind hem stitchine industrial machine in the Collage I went Vogue Style as twenty ten graduate
school of fashion and designing by Joyce Aba Bio was thought by hand Heming and Blind stitches was one mean the hand stitching thanks a lot guys.