Product Documents

What is Planetary Gearbox?

A planetary gearbox is a mechanical device consisting of sun gear, the planet gears, the planet gears’ carrier, and the ring gear. Sun gear is located at the center that transmits torque to planet gears orbiting around the sun gear. Planet and sun gears are located

inside the ring gear.

Multi-staged planetary gearbox is available by connecting the individual stage in sequence. With the gear unit combination the individual stage is sized to the torque requirement.

Function of Planetary Gearbox?

A planetary gearbox is a gear system utilized to increase the output torque and reduce load inertia while slowdown the speed. A gearbox provides speed and torque conversions from a rotating power source to another device using gear

ratio. It can be used in various situations, such as precise machine tools, and anywhere else mechanical equipment.

Application of Planetary Gearbox?

Planetary Gearbox is used on high precision motion control application that requires high torque, torsional stiffness and low backlash, specifics of which will vary by application.

Planetary Gearbox increases the torque by the stage of reduction ratio, making it possible to run the motor at a higher, more efficient speed. The inertia reflects back to the motor is reduced for increased stability. Using a planetary gearbox allows machine builder using a smaller, less expensive motion control package. The application of planetary gearbox covers the entire range of automation. It is frequently found in fields following.

1. Pick and Place Systems
2. Loading and unloading gantry Robots
3. Driving Rotary and Linear Actuators
4. Packaging Machines
5. Positioning Tables
6. Material Handling Systems
7. CNC Routers
8. Plasma Cutting Machines
9. Machine Tools
10. Industrial Conveyor
11. Industrial Printing Machines
12. Feeding Machines

How to select a proper Planetary Gearbox?

-Gear Ratio:

Generally speaking, the reduction ratio can be simply explained by the formula: Reduction Ratio = RPM-servo motor / RPM-gearbox output Gear ratio also can be 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.

-Output Torque:

Output torque is important parameter when choosing a planetary gearbox. Gear reduction reduces the relatively high rotational speed of motor, delivering a lower rotational speed at the output end.

-Overload:

Torque Peak overload torque is the short-term overloading of the permitted output torque.

-Speed (rpm):

Speed is proportional to the gear ratio of the system. If the input gear has more teeth than the output gear, the result will be 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.

-Backlash:

Backlash is the angle in which the output shaft of a 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. If the motion cycle is exactly repeated the backlash of planetary gearbox has theoretically not influence on the repeatability. However, in precision applications with load reversals like Robotics, Automation, CNC Machines, etc., backlash is crucial for accuracy and positioning.

Motor Mounting Instruction

Mothod A:

1. Check the specification of motor and gear reducer are correct and match.
2. Clean the mounting surface greases and dust free.

Method B:
1. Adjust position of gear reducer clamping collar bolt line-up with mounting hole.

2. If the motor shaft has a key-way, remove key. And insert balance key if have.
3. Check the motor shaft size, insert bushing into clamping collar if necessary.
4. Fit the motor into gear reducer.
5. Tighten both side of clamping collar bolts with 5% specified torque by hex wrench.

Method C:

1. Set motor and gear reducer at vertical position.
2. Tighten mounting bolts (washer) with opposite angle order and with 5% specified torque by hex wrench (Pre-coating thread-locking fluid on mounting bolts is necessary).
3. Tighten mounting bolts (washer) with opposite angle order and with 100% specified torque by torque wrench.

Method D:

1. Tighten both side of clamping collar bolts with 100% specified torque by torque wrench.

 

By choosing SHENGPLUS  you can be sure you have the most robust and durable mechanical drive possible in your driven actuator and electric cylinder applications. This commitment to quality and long life makes SHENGPLUS your sure choice for driven actuator and electric cylinder in a variety of industrial applications.

Application

1. ﹥ Automotive / Tire / Rubber
2. ﹥ Food and Beverage
3. ﹥ Forestry
4. ﹥ Oil and Gas
5. ﹥ Automated Machinery
6. ﹥ Solar Tracking System
7. ﹥ Defense Aerospace
8. ﹥ Transportation
9. ﹥ Electric Medical Bed
10. ﹥ Electric Wheelchair
11. ﹥ Patient Lift
12. ﹥ Treadmill Ramp Simulator
13. ﹥ Electric Window Opener
14. ﹥ Electric Door Opener

What are reasons one might have for choosing electric actuators over hydraulic actuators?

A: Hydraulic actuators have some advantages in certain cases. They have a high power density, low component acquisition cost, moderate to high stiffness, high speed, and are

a commonly used technology with several commercial outlets. However, in certain situations, hydraulic actuators can be less beneficial to a system. They have a moderate accuracy and repeatability without the additional help of extra tuning equipment. They also have intricate and complex installation and maintenance due to hydraulic pumps and tubing. Additionally, they have a high installation cost, low energy efficiency, large environmental impacts, and limited scalability and modularity. These are the cases where electric actuators offer a better solution.

What are the primary benefits of using an electric actuator system over hydraulics?

A: Electric actuators offer high speed and force, are flexible and easily programmable for a variety of load conditions, have high accuracy and repeatability, are efficient, simple to install, require little maintenance, and are environmentally friendly. By not using a hydraulic system, the user can eliminate oil leaks, reduce pollution, and improve worker safety. Other environmental benefits of electric actuation include: higher energy efficiency/lower energy consumption; quieter operation/lower noise levels; and near zero power consumption when not operating (hydraulic system pumps operating during idle periods consume substantial energy). Additionally, there is no disposal of hydraulic fluids (upon normal maintenance or repair, hydraulic fluids need to be disposed of properly). Electric actuators are also a non-toxic solution especially in the food industry.

Ball screw pre-tension design

High-lead ball screw is an indispensable component for high-speed machine tools in the 21st century. High-speed cutting technology is an important breakthrough. Therefore, the role of high-lead ball screws in high-speed machine tools is even more important. The ball screw system uses Gothic thread, and the size of the ball diameter is used to select a predetermined preload.

The accuracy of the system is often one of the important factors determining the good or bad, but the temperature rise and thermal displacement of the ball screw is an important factor affecting the accuracy of the feed. Improve the temperature rise and thermal displacement of the ball screw and suppress the temperature rise and displacement. The ball screw pre-tensioning method is used to improve the thermal displacement problem, but when the temperature rise exceeds the temperature, the thermal displacement problem may reappear. Therefore, the best solution is to cooperate with the method of suppressing the temperature rise or install a necessary loop control system in parallel

Application of ballscrew

﹥ Automatic Industrial.

﹥ Semi-conductor Industrial.

﹥ Industrial mechanism.

﹥ Medical equipment

 

Characteristic of ballscrew

1 Coefficient of friction.

2 Precision of position.

3 Effective duration.

4 High speed tuning & both forward and reverse.

5 Element of linear and swiveling.

T-type Nut

For the circulation of this type, the steel balls roll forward along the grooves between the screws and the nut, then are picked up at the front end of the external circulation tube, which further pass through the circulation tube and circle around to the other end of the circulation tube, finally return to the origin point. It is generally provided with several rolls of steel balls and a single pass circulation tube, both routing type and projecting tube type of profile may be adopted.

I-type Nut

In this type, the steel balls move along the grooves of the internal circulator, diagonally pass over the tooth tops of the screws, then return to the origin point. It generally possesses one roll of steel balls and one single pass circulation. This type of screws has at least one end with completely through threading, suitable for screws of smaller diameters, it is equipped with metal circulator.

Conditions of the Ball Screw

The following conditions are required when selecting a Ball Screw

Velocity Diagram

Transfer orientation	Horizontal, Vertical, etc.
Transferred mass	m (kg)
Table guide method	Sliding, Rolling
Frictional coefficient of the guide surface	µ (—)
Guide surface resistance	f (N)
External load in the axial direction	F (N)
Desired service life time	L h(Hour)
Stroke length	ℓs (mm)
Operating speed	Vmax (m/s)
Acceleration	t1 (s)
Even speed	t2 (s)
Deceleration	t3 (s)
Acceleration	α = Vmax / t1 (m/s)²
Acceleration distance	ℓ1 = Vmax × t1 × 1000 (mm)
Even speed distance	ℓ2 = Vmax × t2 × 1000 (mm)
Deceleration distance	ℓ3 = Vmax × t3 × 1000/2 (mm)
Number of reciprocations per minute	n (min-1)
Positioning accuracy	(mm)
Positioning accuracy repeatability	(mm)
Backlash	(mm)
Minimum feed amount	S (mm/pulse)
Driving motor	AC servomotor, stepping motor, etc.
The rated rotation speed of the motor	NMO (min-1)
Inertial moment of the motor	JM (kg · m²)
Motor resolution	pulse / rev.
Reduction ratio	A (—)

 

Point to Note of Lubrication and Safety Design

Groove Shape of Precision Ball Screw

When axial play is minimized in conventional screw-nut assemblies, the actuating torque becomes excessive and the operation is not smooth.

The axial play in precision ball screws may be reduced to zero by preloading and a light smooth operation is still possible. Therefore, both low torque and high rigidity can be obtained simultaneously. Ball screws have gothic arch groove profiles which allow these conditions to be achieved.

Groove Shape of Precision Ball Screw

Lubricating

Adequate lubrication must be provided when ball screw is used, insufficient lubrication will result in contact of metal, which in turn leads to increase of friction and friction loss, thus cause failure of shortening of service life.

Lubricants applied to ball screws can be divided into 2 types, namely lubricating oil and consistent grease. In general speaking, in respect of maintenance, consistent grease will lead to increase of dynamic friction torque linearly along with increase of rotating speed, hence oil lubrication is deemed the better way when speed exceeds 3-5 m/min; however, don’t forget the fact that there have been examples that using grease has been capable of achieving speed of 10 m/min, with respect to the equipment.

Inspection of lubrication and interval of refill

Contaminant Prevention

Any foreign matter or water, if allowed to enter the ball screw, may increase friction and cause damage.

For example, the entry of chips or cutting oil may be expected with machine tools depending on the work environment. Where entry of foreign matter is anticipated, use a bellows or telescopic cover as shown in fig. to cover the screw shaft completely.

Dust Proof Method

Offset load

When offset load phenomenon occurs, screw life and noise tend to be directly affected, which would usually be accompanied with hand feel of rough running. In the event unload running and running right after assembling demonstrate different degree of cases, this should be ascribed to the poor assembly accuracy which will produce offset load phenomenon as shown in Fig.

What Are Indexing Drives?

Indexing Drives, also known as roll gear cam index. According to the needs of users’ time series production cams, cam rotation drives output shaft. The output shaft shows intermittent movement of mechanical products since its internal structure is all-mechanical. It also has a long service life.

The output shaft is also a roller turret assembly with 6, 8, 10, 12, 16, 20 and 24 rollers on the assembly.

Applications of Indexing Drives?

The indexing drives are widely used and usually based on automation and semi-automation. Currently, it is widely being used in equipment testing, electronics, and in pharmaceutical, printing, food packaging, glass, ceramic, and chemical machinery. Practical applications include: automatic welding, vacuum forming, filament winding, high-speed punching, line punching, dynamic pressure, tapping, assembly, feeding, processing, printing, pad printing, screen printing, bronzing, inspection, sorting, packaging, consistency of capacitance, classification, and resistance diodes.

Composition of Indexing Drives?

The main mechanism is a combination of a cam (input shaft) and a roller turret (output shaft), with cast iron shells, bearing, oil seals, eccentric nuts, and several components of different sizes and shapes.

What Are the Characteristics of the Indexing Drives?

1. Step-by-step (intermittence) – for the pointing accuracy to be high, the revolving precision may amount to ±20~±40 seconds, including a fluctuation function and a fluctuation repetition precision in 0.05mm.
2. The zero backlash is designed to ensure a non-recoil of the divider as a result of the structural design through the preloading action from the center of the force of axis.
3. For a large transmission torque, the user refers to the indexing drive as a cam type reducer.
4. At high speed operation and stable vibrations, the maximum speed can be affected up to 200~600rpm by load, split number, driving angle, lifting stroke, and cam type.

*Angle units are in degrees, minutes, and seconds, 1 degrees = 60 Minutes, 1 minutes = 60 seconds

* The Index Drives can use a specific ratio and have a non-stop 360-degree cam.

How to Use the Indexing Drives?

The output of the indexing drives usually connected to a disk or conveyor belt.

How to Drive the Indexing Drives?

Connect the induction motor to the reducer or use the servo motor. Users with special needs will have additional power distribution for electronic control to extend the stop time as needed. There are range limits in the indexing drive’s motion stop ratio.

*Please do not connect the induction motor to the access input shaft directly. If the motor is docked incorrectly, it may damage the input shaft.

 

The Service Life of the Indexing Drives?

Many of the indexing drives produced by our company have required adjustments or repairs after 10 years of continuous use. Normal usage and maintenance of indexing drives will give the product a longer life.

The Characteristics of Roller Gear Cam Indexing Drives?

In order to achieve reliable and high speed of the dividing mechanism, with automation and labor-saving automatic machine and special machine, we use the method of cam dividing, and the roller gear mechanism in dividing has earned the most stable and reassuring of the evaluation.

1. Cam Drive Track by the 5-axis CNC Grinder Precision grinding molding, smooth operation, accurate positioning, no sliding offset phenomenon, will not produce cumulative tolerances.
2. The cam has high precision, no backlash during operation, accurate positioning (within 30 seconds), low noise, and special acceleration and deceleration motion curve, so it can be swiveled at high speed. The camshaft rotation speed can reach 600RPM or more.
3. The cam is made of high-grade alloy steel and refined carburizing heat treatment material which is strong and tough. It is immersed in the engine oil with the cam bearing of the output shaft, and has less wear at high speed. It can ensure long life and continuous operation can reach more than 12,000 hours without abrasion.
4. The roller gear cam dividing mechanism has the advantages of simple structure, high reliability and zero failure rate.
5. The total number of segments is large (currently 120 equal parts).
6. It can be installed in any direction, and easy to be used.

What Are the Number of Divisions, the Driving Angle, and the Stopping Angle?

1. The number of divisions is also called the number of stations. If there are 8 workstations on the disc, there will be 8 divisions.
2. Each division consists of 1 rotation plus 1 stop action.
3. The drive angle: stop angle = motion-stop ratio. The motion-stop ratio is the ratio of time of rotation and stopping in 1 workstation per unit time. The common interval of motion stop is 3:1-1:2, and the greater the driving angle, the relatively smoother operation of the indexing drives.

Correct Usage and Maintenance of the Indexing Drives?

# Calculate the load torque according to the load conditions, and then select the proper Indexing Drives correctly.

The internal parts of the roller cam divider can bear the limit of load. Therefore, the calculated torque must be calculated according to the formula, and then the required specifications should be selected, so that the cam indexer can play the most perfect function.

# It is necessary to have anti-collision devices to make operation safer.

When the Cam Indexing Drives is in operation, in order to prevent damage caused by human negligence or the collision of other factors, the torque limiter must be installed during installation and the appropriate slip torque should be adjusted to avoid causing damage during the collision.

#Under the permitted circumstances, please use the larger driving angle as far as possible.

Cam Indexing Drives are used in the whole machine as the cam mechanism, in order to obtain a longer working time, the relative must choose a smaller drive angle of Indexing Drives. A smaller drive angle of the cam track surface slope is high, roller thrust to produce multi-directional force, and the driving angle of the cam has a variety of other favorable factors, so please choose a larger drive angle splitter.

# Using the lubricating oil normally to extend the service life.

After the Cam Indexing Drives is re-installed and fixed, it is necessary to replace the exhaust plug head into the oil outlet to exclude the higher air pressure that caused by thermal expansion in operation

# Please contact the technical department of Fei Jih Precision Machinery if the original disc diameter exceeds seven times the axial distance between the input shaft and the output shaft.

#If there is any problem or need more detailed information, please contact our technical department. We will serve you.

How to Maintain Indexing Drives?

1. To check the level of oil, and make sure the indexing drive is not running. If the oil line is not visible in the oil mirror, oil should immediately be added.
2. After the first 1,000 hours of operation, the oil should be replaced. Then, replace the oil after every 3,000 hours of operation or after each year.
3. The lubricants of the indexing drives and the lubricating oil splitter have great influence on the life span. Please use the CPC Corporation, Taiwan extreme pressure oil HD220.
4. The inspection of the driving part, the periodic inspection of the driving part of the relation between the camshaft of the indexing drive and the output shaft, connecting shaft, pulley, sprocket, gear and output shaft of the drive part is loose, and pay attention to the tooth belt, chain tension, gear clearance and so on.

5.For any indexing drives failure, immediately stop operation and contact Fei Jih Precision Machinery Corporation.