Toothed belts, toothed belt pulleys
Toothed belts used in combination with toothed pulleys form a compact drive with high power density and outstanding efficiency. They are low-maintenance and low-noise, resistant to a wide range of environmental influences and, when correctly configured, extremely durable. Provided that the individual components are adequately matched, toothed belt systems work extremely precisely, with excellent synchronisation characteristics and completely without slippage.
Toothed belt pulleys, Splined shafts, Toothed belts
Toothed belt drives are always used where synchronous and smooth power transmission should be ensured.
Various typs of toothed belts and toothed belt pulleys are available from norelem:
The version T (T5 & T10) is the standard version. This is the toothed belt type with the classic trapezoidal profile as depicted in DIN 7721. This sort of drive is often used because it combines inexpensive and reliable properties.
The version AT (AT5 & AT10) is the reinforced version for transferring higher torques. The higher stiffness of AT toothed belts requires that larger diameter pulleys are used than with T toothed belts.
The High Torque Drive (HDT) toothed belts with rounded teeth ensure more consistent tension curve. HDT toothed belts are especially suitable for precision tasks.
Here is an overview of the advantages of a toothed belt drive:
- low wear
- almost maintenance-free
- good resistance to fats, oils and many other chemicals
- high power transmission (AT & HTD)
- low belt elongation
- operating temperature range between -30 °C and +80 °C (T & AT)
The toothed belts are made from polyurethane. The combination of elastomer teeth and steel reinforcement cords ensure high power transmission. Polyurethane belts are maintenance-free, low-noise, robust and extremely durable. In addition, this material enables ca. 30% more output with smaller dimensioning of the drive as by classical T and AT toothed belts. The toothed belts provide high power transmission in various industrial applications such as machine tools, industrial robots or packaging machines. The endless belts are available in the standard length range of 165 mm to 2250 mm.
Toothed belt pulleys
High quality aluminium toothed pulleys are available from norelem. The toothed pulleys are machined to high tolerances. Each pulley is pre-bored and balanced. In addition, splined shafts to manufacture customised toothed pulleys and clamp plates for joining the ends of toothed belt are available from the norelem online shop.
Polyurethane toothed belts
Polyurethane is very wear resistant. Belts made from this material are reinforced with steel cords. Polyurethane toothed belts enable synchronous and very quiet power transmission. The low maintenance requirements make these toothed belt drives very economically attractive.
Toothed belts 22052 / 22054 / 22057 / 22059:
Drive installation
Diagrams and performance charts for size selection can be found in the PDF documents on the product pages. The following should be taken into consideration during installation:
- the axis should lay parallel to each other (a laser enables precise alignment)
- use the largest possible pulley diameter
- do not forcefully lever the belt over rim flange
- plan enough room to allow for adjustments
Belt tension
The correct alignment and tension of the drive is very important for a long service life and quiet running during operation. By drives with fixed centre distances the use of tension rollers is recommended so that the belt tension can be effectively adjusted. A toothed idler on the slack side of the belt is preferable to a back tension pulley. A smooth back tension pulley causes bending. These bends result in a shorter service life for the drive.
Toothed belts should never be kinked. Ensure that the toothed belts are not tightly rolled or bent when in storage. Direct sunlight or contact with chemical substances should also be avoided.
Toothed belts 22062
General
The norelem HTD tooth profile is certified according to ISO 13050. The special tooth form reduces the typical running noise of the belt to a minimum - especially in comparison to the classic trapezoid tooth form belts from norelem. An additional advantage is the high resistance to various environmental influences. If the HTD tooth profile drives are dimensioned correctly, they are also extremely durable.
Drive torque
The transferable output is several times higher compared to a classic inch pitch trapezoidal profile. The tooth contour (round) of the HDT belts ensures for a high degree of protection against tooth jumps. The axis must also be parallel to each other with HTD toothed belts. The selection of the number of teeth required is similar to that for the other norelem toothed belts.
Installation
The belt should be mounted on the pulleys manually without the aid of tools such as screwdrivers or similar. This is done to prevent damage to the belt and pulley or rim flange. The toothed pulleys must be precisely aligned. After adjustment to the correct tension, run the drive for a short while and then check the tension and alignment again. Readjust if necessary.
Repeat this control after roughly one hour running time. A small reduction of the frequency is normal. Control all fastenings on the drive and, if necessary tighten them them prevent loosening through operational vibrations etc. If a belt has to be removed at a later date, the current natural frequency must be determined beforehand. This is used when the belt is remounted. It is not required when the old belt is replaced by a new one, in this case the values from the initial installation are used.