Factors To Consider When Looking For Harmonic Drive Gearboxes Online
Harmonic drive gearboxes from companies like UK Harmonic Drives have become a popular choice in many industries for various reasons. They offer high power density, are lightweight and compact, and can handle high speeds and torques. Additionally, they are often more reliable than other gearbox types. When selecting the right harmonic drive gearbox for your needs, here’s what to look for.
Gear ratio
The relationship between the circumferences of two gears is known as a gear ratio. The number of teeth on a gear is usually proportional to its circumference. This implies that the gear with a larger circumference will have more gear teeth; therefore, their corresponding circumferences can also provide an accurate gear ratio. If one gear has 36 teeth and another 12, the Gear Ratio would be 3:1.
Output torque
The gear ratio determines the output torque. A large gear ratio would be utilised to produce a high output torque. Using a greater motor speed at the output shaft, using a huge gear ratio will reduce the output shaft speed of the motor. Using a less gear ratio, on the other hand, delivers a lower output torque value into the system with a higher motor speed at the output shaft. This statement illustrates that both torque and speed are inverse proportions.
Speed (RPM)
The gear ratio of a NEMA 17 harmonic drive is directly related to its speed. If the input gear has more teeth than the output gear, the system’s output shaft will experience an increase in speed. The speed of the output shaft will decrease when the input has more gear teeth at the output than at the input. The output speed is determined by dividing the input speed by the gear ratio. The higher the ratio, the lower the output speed, and vice versa.
Service factor
The service factor is the first step for most gearbox makers. This instrument compensates for factors like the type of input, number of usage hours per day, and shock or vibration in the application. A unit that experiences an irregular shock, such as a grinding process, will require a higher service factor than a uniformly loaded one. Similarly, a device only operated part-time would have a lower service factor than one utilised 24 hours a day.
Class of service
After that, the concept of class is determined. A service class 2 is typical for a unit driven by a simple AC motor operating an evenly loaded, constant speed conveyor for 20 hours each day.
Overhung load
Once the micro harmonic drive has been chosen, the gearbox manufacturer’s catalogue or website will show a maximum overhung load value for that size unit. Suppose the load in an application is greater than the permitted amount. In that case, the gearbox may need to be upgraded to accommodate the overhung loading.
Mounting
While certain mounting patterns apply to most gearbox sizes, each unit varies in terms of options. However, there are many more alternatives. There are several other choices, such as mounting feet above or below the gearbox’s body. Hollow outputs, input and output arrangement can all be chosen. Harmonic drive gearbox manufacturers offer extensive information on mounting methods and dimensions in catalogues and websites.
Helical gearboxes
Micro harmonic drive helical gearboxes are small and low-powered. These are frequently used in heavy-duty or light-duty operations, such as crushers, extruders, coolers, and conveyors. It stands out because it runs at a fixed angle and maintains constant contact for an extended period. Engineers can utilise helical gearboxes to decrease gear tooth counts by improving load and transmission ratios.
Bevel helical gearbox: often used to transfer rotary motion between non-parallel shafts. A cone-shaped surface encircles a curved row of teeth with skewed bevel helical gears. Skew bevel helical gearbox: Has a more rigid structure than the regular skew bevel helical gearbox. Engineers may customise the number of teeth and cogs.
Planetary gearboxes
Planetary gearboxes have parallel input and output shafts. This allows for a high level of torque density, which transmits the most torque in the narrowest form. Because torque is divided among three gears with equal dimensions, these NEMA 17 harmonic drive gearboxes send out almost three times the power of a conventional gearbox. They’re also noted for their low backlash, low mass inertia, and high efficiency.
Worm reduction gearboxes
Gearboxes with worm reduction gearboxes have a huge worm wheel that rotates screw-like. This enables the gearbox to increase speed reduction between non-intersecting crossed axis shafts. Although strong, they are among the least efficient gearboxes since they operate on sliding action rather than rolling action. Consequently, when utilising worm reduction gearing, careful analysis of motor selection is necessary.
The harmonic drive is a gearbox with two parallel shafts and uses the principle of interference. This means that one wheel rolls over another to transmit power from input to output through an elastic coupling, which transfers torque without transmitting any shock or vibration. Harmonic drives are most often used in applications where high-torque transmission needs to take place with minimal backlash and low mass inertia. If you’re looking for your next harmonic drive, hopefully, this article has helped you choose the right one.
