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tiangmj
Posts: 1
Joined: Tue Aug 21, 2012 8:44 pm

We have a very big table which is about 4400mm and the load on the table and table itself is about 400kg.

Do oriental motor have any motor that capable to rotate the table? By which way?

Is this the best way to turn the table?

The speed required is only 0.5rpm and we need it to stop immediately if the power is off.

om_tech_support_JT
Posts: 1058
Joined: Fri Mar 12, 2010 2:59 pm
Location: Torrance, CA
Contact:

There are a few ways for you automate the rotation of your table. The picture you attached above shows a belt/pulley setup. We can also do a gear drive (see animation below). However, the best setup/design will depend on your other requirements. For example, if you don't want to deal with a belt because of friction, slippage, or noise, use a gear drive. There are also belts with different characteristics that you'll need to consider.

Gears_animation.gif (52.9 KiB) Viewed 18512 times

SOURCE: http://en.wikipedia.org/wiki/Gear

We cannot directly drive your table with one of our motors because your load inertia would be too large for our motors to handle alone. We'll need a very high gear ratio. Since we don't offer extremely high gear ratios with our motors, we'll need you to add an external gear ratio to help reflect/reduce the inertia.

I have simulated a belt-pulley setup with our FREE easy-to-use online sizing software. This is available on our website. Please see attachment for a detailed report that is generated by our software. It will list your load inertia, speed, and torque requirements, as well as calculations done to determine those values.

SIZING REPORT:
Forum082212belt-pulley calculation.pdf

What this report will show is a theoretical mechanical setup with the following components:
A 4400 mm diameter uniformly distributed / balanced table that weighs 400 kg. A 25 mm 0.5 kg shaft will be attached to the table at its center. I have added a support bearing underneath the table with a radius of 2000 mm with a friction coefficient of 0.05. The other end of the shaft will be attached to a secondary pulley of 500 mm diameter, 2 kg. That 500 mm pulley is connected to a 25 mm diameter, 0.5 kg primary pulley with a belt. The belt reduction ratio is 20:1. The motor shaft will be driving the 25 mm primary pulley at its center. I selected variable speed requirements since you seem to only need to control speed and stop accurately. I put in a speed range requirement of 0.1~1 RPM to allow for some flexibility. I used a system efficiency of 90% and a torque safety factor of 1.5x. This is just like the picture you attached above. If you need to change any parameters such as coefficient of friction, support bearing radius, or pulley sizes, you can try out our online tool, or let me know of your changes so I can generate a new report.

FYI: the online motor sizing tool does not recommend a specific model number. It only calculates your requirements for you. There are usually a number of options that may work. If you need help selecting a product, please discuss your application with our knowledgeable technical support group so we can help you select the ideal product for your specific purpose.

SIZING RESULTS SUMMARY:
LOAD INERTIA = 2.42 kg.m² (132,313 oz.in²)
REQUIRED SPEED = 2~20 RPM
REQUIRED TORQUE = 21.78 Nm (193 lb-in)

I will select a brushless motor system based on your high torque and speed control requirements. Our brushless gearmotors can provide close to 1000 lb-in of consistent torque (up to 970 lb-in or 110 Nm) up to its rated speed and can maintain its set speed even with changes to load, voltage, or temperature. Step motors do handle larger inertias better, but I will go with a brushless motor option first since you do not need precise positioning capabilities. Let me know if you would like me to calculate for a step motor option instead.

Here's one motor system that would work based on the sizing results.

RECOMMENDED BRUSHLESS GEARMOTOR AND DRIVER PACKAGE MODEL
[ BX6400S-200S ]
-outputs 610 lb-in rated torque from 0.15~15 RPM (15 RPM = 0.75 RPM)
-can handle a load inertia of up to 200,000 oz.in²
WEB: http://catalog.orientalmotor.com/item/b ... 6400s-200s

This motor will coast to a stop if power is removed from its driver. If you need instantaneous stop, you will need a motor with an electromagnetic brake. An electromagnetic brake will lock the motor shaft in place when power is turned off. It will release when power is provided again. It's designed as a safety brake to hold the load in place if power is turned off.

RECOMMENDED ELECTROMAGNETIC BRAKE VERSION OF THE ABOVE MODEL:
[ BX6400SM-200S ]
WEB: http://catalog.orientalmotor.com/item/b ... 400sm-200s

FYI: an optional control module, OPX-1A, is available if you want to access the extended functions of the BX driver. With the OPX-1A, you can perform torque-limiting operation, digital speed setting, monitoring functions, and positioning operation using its encoder feedback. Without it, the BX can still perform as a speed control system.

If you do not like the BX series for some reason, we do have several other products that may work for you. Please provide more requirements so we can narrow down the choices for you.

om_tech_support_JT
Posts: 1058
Joined: Fri Mar 12, 2010 2:59 pm
Location: Torrance, CA
Contact:

Here's the link for our FREE online motor sizing calculator tool:
http://www.orientalmotor.com/support/motor-sizing.html
-registration required.

om_tech_support_JT
Posts: 1058
Joined: Fri Mar 12, 2010 2:59 pm
Location: Torrance, CA
Contact:

Hi I am just following up my product recommendation to see what your thoughts were. Let me know if you need any more support.

patcha2565
Posts: 3
Joined: Wed Nov 23, 2016 2:02 am