Right Angle Gearbox
The Right Angle Gearbox product lines offer the precision required, at prices that make them an affordable choice! Right Angle Gearbox products are available in sizes from 40 mm to 120mm, which is ideal for motors ranging from NEMA 17 to larger than NEMA 42. The Right Angle Gearbox is built with the design goal of offering a cost-effective product without sacrificing quality. Prices appear on this web site, with all the information required to select the perfect Right Angle Gearbox product for your application.
• Sizes: NEMA 17, 23, 34 and 42
• Gear Ratios: 22 Ratios from 3:1 to 512:1
• Backlash: As low as 5 Arc-Min
• Torque Up To 36,816 Ounce-Inches
• Right Angle Ideal for Redirecting Power Flow
• Maintenance-Free, Lifetime Lubrication
• Compatible with Most Servo, Stepper, AC or DC Motors
Right Angle Gearbox Fundamentals
- Right-Angle Gearbox - What is a Right-Angle Gearbox
- Right-Angle Gearbox - Where is a Right-Angle Gearbox Used
- Right-Angle Gearbox - Types of Right-Angle Gearboxes
- Right-Angle Gearbox - Cost of a Right-Angle Gearbox
- Right-Angle Gearbox - How does a Right-Angle Gearbox Work
- Right-Angle Gearbox - Advantages and Disadvantages
- Right-Angle Gearbox - FAQ
- Right-Angle Gearbox - How is a Right-Angle Gearbox Controlled
- Right-Angle Gearbox - How to Select the Appropriate Right-Angle Gearbox
- Right-Angle Gearbox - Physical Properties
A right-angle gearbox is a mechanical device utilized to increase the output torque or change the speed (RPM) of a motor. The motor’s shaft is attached to one end of the right-angle gearbox and through the internal configuration of gears of a right-angle gearbox, provides a given output torque and speed determined by the gear ratio.
Advancements in technology and the evolution of gears have made a more efficient and powerful right-angle gearbox to be developed and manufactured at lower costs. Toothed gear systems have evolved from fixed axis gear systems to new and improved gears including helical, cycloid, spur, worm and planetary gear systems. A right-angle gearbox is widely used in applications that require desired output speed (RPM), control the direction of rotation, and to translate torque or power from one input shaft to another.
A right-angle gearbox is used in a variety of industries:
• Aerospace – In the aerospace industry, a right-angle gearbox is used in space and air travel, i.e. Airplanes, missiles, space vehicles, space shuttles and engines.
• Agriculture – In the agriculture industry, a right-angle gearbox is used for plowing, irrigation, pest and insect control, tractors and pumps.
• Automotive – In the automotive industry, a right-angle gearbox is used in cars, helicopters, buses and motorcycles
• Construction – In the construction industry, a right-angle gearbox is used in heavy machinery such as cranes, forklifts, bulldozers and tractors.
• Food Processing – In the food processing industry, a right-angle gearbox is used in conveyor systems, the processing of meat and vegetable products, and packaging applications.
• Marine Industry – In the marine industry, a right-angle gearbox is used on boats and yatchs.
• Medical – In the medical industry, a right-angle gearbox is used in surgical tables, patient beds, medical diagnostic machines, dental equipment and MRI and CAT scan machines.
• Power Plants – In power plants, a right-angle gearbox is implemented in transformers, generators and turbines.
There are many types of right-angle gearboxes manufactured throughout the world. One of the main differences between each individual right-angle gearbox is their performance characteristics. Choosing from the various right-angle gearbox types is application dependent. A right-angle gearbox is available in many sizes, ratios, efficiencies and backlash characteristics. All of these design factors will affect the performance and cost of a right-angle gearbox. There are several right-angle gearbox types which are listed below:
A bevel gearbox is mainly used in right angle, low gear ratio applications, due to their shafts perpendicular arrangement to one another. A bevel gearbox makes it possible to change operating angles. Two different types of bevel gearboxes includes straight and spiral. A straight bevel gearbox is used for slow speed applications, and have straight and tapered teeth. The spiral bevel gearbox has curved and oblique teeth, and are used mainly for high-performance, high speed applications. A bevel gearbox is typically constructed of cast iron, aluminum alloy or other steel materials.
Unlike spur gears, gears on a helical gearbox is cut at angles which allow for gradual contact between the gear teeth. This design provides for a smooth and quiet operation. A helical gearbox is compact, efficient and available in a 5:1 ratio per stage. A helical gearbox can be used on non-parallel and perpendicular shafts. These gearbox types are applicable in high horsepower and efficient applications. A helical gearbox is typically constructed with cast iron, aluminum alloy or iron material.
A spur gearbox is compact, cost-effective, efficient and readily available. A spur gearboxe is available in a 10:1 ratio per stage, made with straight teeth mounted on a parallel shaft. The noise level of a spur gearbox is relatively high due to colliding teeth of the gears. In comparison with a worm gearbox, they are more expensive, noisier and have less shock capability. The spur gearbox is widely used in applications requiring an increase or reduction in speed and high output torque. A spur gearbox is typically constructed with metals such as steel or brass, and plastics such as nylon or polycarbonate.
A worm gearbox can handle high shock loads, and is low in noise and maintenance-free, but less efficient than other gearbox types. It is also available in right angle configuration. The worm gearbox configuration allows the worm to turn the gear with ease; however, the gear cannot turn the worm. The prevention of the gear to move the worm can be utilized as a braking system. When the gearbox is turned off, it is held in a locked position. A worm gearbox is typically constructed of aluminum, stainless steel and cast iron.
A planetary gearbox is named so due to their resemblance of the solar system. A planetary gearbox consists of three main components: sun gear, ring gear and two or more planet gears. The sun gear is the located in the center, the ring gear is the outermost gear, and the planet gears are the gears surrounding the sun gear inside the ring gear. A planetary gearbox is used in applications requiring low backlash, compact size, high efficiency, resistance to shock, and high torque to weight ratio.
The price of a right-angle gearbox varies and is typically affected by size, accuracy specifications, backlash, and the gear ratio, as well as the specific manufacturer. A right-angle gearbox with a backlash in the range of 30 arc-minutes may cost as low as $500. The cost for a right-angle gearbox with a backlash value under 5 arc-minutes will cost more than a right-angle gearbox with high backlash values. Below is a list of right-angle gearbox products offered by Anaheim Automation. Comprehensive specifications and pricing is available on our website at AnaheimAutomation.com, for each of the offered types:
• Economy Right-Angle Gearbox
• High-Grade Right-Angle Gearbox
• Right-Angle Planetary Right-Angle Gearbox
• Rotating Output Flange Right-Angle Gearbox
Each right-angle gearbox works in a similar fashion. The directions the gears rotate are dependent on the input direction and orientation of the gears. For example, if the initial gear is rotating in a clockwise direction, the gear it engages will rotate counterclockwise. This continues down the line for multiple gears. The combination of different size gears and the number of teeth on each gear plays a significant role in the output torque and speed of the shaft. High gear ratios allow for more output torque and lower speeds, while lower gear ratios allow for higher output speed and less output torque.
A planetary gearbox works relatively the same. A planetary gearbox system is constructed with three main components: a central sun gear, a planet carrier (carrying one or more planet gears) and an annulus (an outer ring). The central sun gear is orbited by planet gears (of the same size) mounted to the planet carrier. The planet gears are meshed with the sun gear while the outer rings teeth mesh with the planet gears. There are several configurations for a gearbox system. Typical configurations consist of three components: the input, the output and one stationary component.
For example: one possible configuration is the sun gear as the input, the annulus as the output and the planet carrier remaining stationary. In this configuration, the input shaft rotates the sun gear, the planet gears rotate on their own axes, simultaneously applying a torque to the rotating planet carrier that in turn applies torque to the output shaft (which in this case is the annulus). The rate at which the gears rotate (gear ratio) is determined by the number of teeth in each gear. The torque (power output) is determined by both the number of teeth and by which component in the planetary system is stationary.
Advantages of a Right-Angle Gearbox
• Low noise level
• High efficiency
• High reduction ratios
• Increase/Decrease output torque
• Increase/Decrease output speed
Disadvantages of a Right-Angle Gearbox
• More costly than other drive systems
• Proper lubrication is necessary for smooth running
• Poorly cut teeth may result in excessive vibration and noise during operation
• Quality matters and adds to cost
Q. Are planetary and spur right-angle gearbox types bi-directional?
A. Yes, planetary and spur right-angle gearboxes are designed to be used for bi-directional operation. The direction the input shaft rotates and gear arrangement of the right-angle gearbox will determine the rotation of the output shaft.
Q. Can Anaheim Automation’s motors be combined with a right-angle gearbox?
A. Anaheim Automation’s motors can be assembled with a right-angle gearbox to meet the necessary requirements of an application. Motors and right-angle gearboxes can be purchased separately or be purchased as an assembled unit. Customization is available. Minimum purchase requirements and a Non-Cancellable/Non-Returnable agreement will apply.
Q. What is the lifetime of an Anaheim Automation motor and right-angle gearbox?
A. The lifetime of a motor and right-angle gearbox varies by user application. Certain factors determine the lifetime of a product, such as environment, radial loads (torque), duty cycle, and input power. All these factors play a role in the lifetime of a motor and right-angle gearbox. Anaheim Automation’s experienced Application Engineers are available to provide recommendations on the best products for your specific application criteria.
Q. What type of right-angle gearbox would be used for right angle applications?
A. A bevel and worm right-angle gearboxes are mainly utilized in right angle applications. They offer high efficiency and low gear ratios. A straight bevel right-angle gearbox with straight cut teeth are utilized in slow speed applications, whereas spiral bevel right-angle gearboxes with curved teeth are utilized in high performance, high speed applications. Worm right-angle gearboxes are also available with right angle configurations. They are able to sustain high shock loads, low in noise, maintenance-free but are less efficient than a bevel right-angle gearbox.
Q. Can a right-angle gearbox be backdriven?
A. Some right-angle gearbox types, such as a spur right-angle gearbox can be backdriven, while some, such as the worm right-angle gearbox cannot be backdriven.
Q. How many planet gears are there in a right-angle gearbox?
A. The amount of planetary gears in a right-angle gearbox differs based on specific application requirements. Most planetary right-angle gearbox types consist of two or more planetary gears.
Q. What is the difference between straight cut gears and helical gears?
A. Straight cut gears have straight and tapered teeth, and are used for low speed applications. Helical gears are cut at angles to allow gradual contact between the gear teeth. This allows for smooth and quiet operation. Helical gears are applicable in high horsepower and efficient applications.
The output of a motor (i.e. stepper, brushless, AC and brush motors) is used as the input of the right-angle gearbox and controls the speed at which the right-angle gearbox rotates. The configuration below illustrates the driver controlling the external motor, which is connected as the input shaft of the right-angle gearbox. As a result, when the driver is powered, the motor shaft rotates inside the right-angle gearbox causing the output shaft of the right-angle gearbox to rotate. The output speed and torque is dependent on the internal configuration of the right-angle gearbox.
When considering a right-angle gearbox, many factors need to be considered to meet specific application requirements:
Gear ratios are defined as the correlation between the numbers of teeth of two different gears. Commonly, the number of teeth a gear has is proportional to its circumference. This means that the gear with a larger circumference will have more gear teeth; therefore the relationship between the circumferences of the two gears can also give an accurate gear ratio. For example, if one gear has 36 teeth while another gear has 12 teeth, the gear ratio would be 3:1.
Output torque of the right-angle gearbox is dependent on the gear ratio used. To obtain a high output torque, a large gear ratio would be selected. Using a large gear ratio will lower the output shaft speed of the motor. Inversely, using a lower gear ratio, a smaller output torque value would be delivered into the system, with a greater motor speed at the output shaft of the right-angle gearbox. This statement illustrates the relationship that both torque and speed are inversely proportional to one another.
Speed is proportional to the gear ratio of the right-angle gearbox system. For example, if the input gear has more teeth than the output gear, the result will be an increase in speed at the output shaft. On the other hand, having the reverse scenario with more gear teeth at the output compared to the input will result in a decrease of speed at the output shaft. In general, the output speed can be determined by dividing the input speed by the gear ratio. The higher the ratio the lower the output speed will be and vice versa.
Gear arrangement is an ingenious engineering design that offers various benefits over the traditional fixed axis gear system design. The unique combination of both power transmission efficiency and compact size allows for a lower loss in efficiency of the right-angle gearbox. The more efficient the gear arrangement, (i.e. spur, helical, planetary and worm) the more energy it will allow to be transmitted and converted into torque, rather than energy lost in heat.
Another application factor to be taken into account when selecting a right-angle gearbox is load distribution. Since the load being transmitted is shared among multiple planets, the torque capacity is increased. The higher number of planets in a gear system will increase the load ability and enhance torque density. Gear arrangements improve stability and rotational stiffness because of a balanced system, but it is a complex and more costly design.
One example is a gear arrangement that is a traditional fixed axis gear system with a pinion driving a larger gear on an axis parallel to the shaft. Or, there may be a planetary gear design system with a sun gear (pinion) surrounded by more than one gear (planet gears) and is encompassed in an outer ring gear. The two systems are similar in ratio and volume, but the planetary gear design has three times the higher torque density and three times the stiffness due to the increased number of gear contacts.
Fixed Axis Gear System:
Volume = 1, Torque = 1, Stiffness = 1
Planetary Gear System:
Volume =1, Torque = 3, Stiffness = 3
Other gear arrangements as mentioned in the "Types of Right-Angle Gearboxes" segment of this guide are bevel, helical, cycloid, spur and worm.
Backlash is the angle in which the output shaft of a right-angle gearbox can rotate without the input shaft moving, or the gap between the teeth of two adjacent gears. It is not necessary to consider backlash for applications which do not involve load reversals. However, in precision applications with load reversals like robotics, automation, CNC machines, etc., backlash is crucial for accuracy and positioning.
The physical components of a right-angle gearbox varies from one right-angle gearbox type to another, as well as differences between manufacturers. Most right-angle gearbox types are constructed from steel materials such as iron, aluminum and brass. Unlike right-angle gearbox types, spur gearboxes can be made with plastics such as polycarbonate or nylon. Other than the raw materials used, the orientation of the gear teeth play a major role in the overall efficiency, torque and speed of the system. A straight gear teeth right-angle gearbox is typically used in low-speed applications. This can cause the right-angle gearbox to be noisy, and lower its overall efficiency. A helical gearbox is typically used in high-speed applications. This type of gearbox is quieter in operation than a straight gear teeth right-angle gearbox, which may improve the overall efficiency.
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