Machine Parts

                                             At NASA, we recognize that new space technologies and innovation are the underpinnings of all of our future missions and they feed directly into America’s economic well-being.  We also understand that for our nation to remain strong, our economy requires an advanced, globally competitive manufacturing community that invents and makes high-value-added products and leading-edge technologies.  This work is critical to NASA’s future missions and our nation’s strength and health.  New and innovative partnerships between NASA and cities and communities around the country can leverage our skills and shared goals to benefit America in space and on Earth. Today, a NASA-Ohio partnership announced the names of six small and medium size manufacturers who were selected to receive no-cost technical expertise from NASA subject matter experts to solve challenges with one of their new or existing products.  Cleveland and Cuyahoga Counties

Types of Feed Gearboxes a.       Feed gearbox with sleep gears :  One of its advantages is the small axial dimension. It is possible to design for a large number of feed rates, if kept within the limits of the upper and the lower transmission ratios. Such gearboxes are used, where feed changes are less frequent. The machines are automatic, semi automatic, special purpose and single purpose machine tools. b.       Feed gearbox with slip gear quadrants : Slip gear fitted to shaft having fixed center distance does not give very accurate output speed. It here have a large number of very finely stepped spindle speeds is required and the actual speeds are to be very accurate. The arrangement of the slip gear is changed. Between the fixed axes of the driving shaft and the driven shaft is placed on a carrier. The intermediate shaft can be adjusted by its linear displacement along the slot in the quardant by swiveling it round axis.                   

Depending on the use of the machine tool, the feed gearbox and the feed mechanism as a whole is required to process 1.       A number of feed steps. 2.       A range of feeds. 3.       Absolute values of the rates of feed. 4.       Type of feed series. 5.       The nature of the feed motion. 6.       Type of drive from spindle or form a separate electric motor. 7.       Required accuracy of the feed rates. 8.       Permissible accumulated error of certain transmissions. 9.       Loads applied to the feed gearbox 10.     Frequency with which the feeds are to be changed.                                                  Feed Gearbox     Types of Speed Gear Boxes     Tumbler Gears       Standard Transmission Ratio     Gear Drive System     The Advantage of Cone Pulley Drive     Central Drive system   The Selection of a Motor

As material removed from the job, the tool has to advance relative to the job to cut new areas of the job. This motion is achieved through the feed drive. Importance of a Feed Drives are: 1.       The drive: A feed mechanism may be powered by a separate electric motor or from the spindle drive through kinematic links like gears, chain and belt. 2.       Feed engaging devices: These may be form or friction clutches, sliding gears etc. 3.       Feed reversing devices: While cutting an internal thread the reversing of the feed is usually required. 4.       A safety device for protecting the feed mechanism against overload. Many design of engine lathes incorporate a dropping worm to overcome the problem of overloading. 5.       A geear train for rapid traverse movements of carriages, tables etc. driven by a separat e electric motor or by high speed shafts in the gearbox. 6.       The feed gearbox set at the beginning of the feed.