SYNCHRONOUS BELT

Engine Synchronous belt CR Heat resistance, life HNBR Long life... 

As Synchronous belt transmission ratio is accurate which can satisfy the requirement of detecting robot flexible mobility. Robot adopts synchronous belt transmission mode with one power output shaft on each side. Compared with all motor driven, it can reduce motor number and the flameproof joint number, optimize the stress distribution of flame-proof encloser, increase internal space improve the AMDR s mobility and safety greatly. Synchronous belt is closed in a confined space, avoiding friction sparks produced, improving the safety of the robot. 

Four different types of belt are considered synchronous belts, V-belts, V-ribbed belts and conveyor belts. Each type of belt has a distinct set of failure modes and so each is considered in turn below. Only failures which can be considered to be belt failures have been considered, rather than belt/pulley system failures, so that failures as a result of pulley misalignment, for instance, have not been included. For adhesion related failure modes, methods of predicting belt failure where they have been developed, are outlined. 

Most of the literature pertaining to synchronous belts considers the automotive application of these belts and so this section inevitably has an automotive bias. Figure 12.1 shows the structure of a synchronous belt. As Figure 12.1 shows the belt is made up from an rubber compound with two reinforcements, the first being a tension bearing cord which runs through the middle of the belt, and the second a facing fabric which covers the belt... 

Figure 12.2 Synchronous belt failure modes, a) tooth root cracking, b) cord delamination, c) fabric separation...

K. W. Dalgarno, Synchronous Belt Materials Durability and Performance, University of Bradford, UK, 1991, Ph.D. Thesis. 

Synchronous drives have an advantage over gears and chains in that they can transmit high loads over a wide range of speeds with low noise and no Inbrication requirements. Synchronous belts, like V-ribbed belts, require closer alignment tolerances in order to avoid premature wear or failure. 

There are three basic tooth configurations associated with synchronous belts. The standard trapezoidal shape was introduced in the 1940s. In the 1970s the high torque drive (HTD) belt was introduced with a round-shaped tooth. In more recent years a number of modified curvilinear tooth belts have been introduced with a tooth shape similar to gear teeth (Fig. 5.80). It is very important that each belt type be run in compatible pulleys or sprockets. 

Belts intended to be run as single belts, such as Ught-duty, V-ribbed, and synchronous belts do not require a matching system. 

Be sure to properly align the motor and driven puUeys. V-belt drives should be aligned to within V° or Vw in/ft of center distance. V-ribbed and synchronous belt drives should be installed and aligned to within V° or Mo in/ft of center distance. Misaligned drives can result in V-belt turnover and premature and unusual belt wear leading to shorter belt life. 

The best tension for the belt is the lowest tension at which the V belt will not slip, or synchronous belts will not ratchet (jump grooves).Too much tension shortens belt life and may... 

The most common symptoms, causes, and corrections of V-belt and synchronous-belt failures... 

IP-26 Specification Joint MPTA/RMA/RAC V-Ribbed Belts (1977). H, I, K, L, and M Cross Sections. IP-27 Specification Curvilinear Toothed Synchronous Belts, 8M 14M Patches (1997). 

Kobe, 23rd-27th Oct.1995, p.160-3. 012 FATIGUE FAILURE OF SYNCHRONOUS BELTS Izuka H Tsutsumi S Watanabe K Mashimo S Ohsako N Yamagata, University Mitsuboshi Belting Ltd. 

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