Horizontal Milling Machines and Accessories

Horizontal Milling Machines

Manufacturing-type

•Cutter height is controlled by vertical movement of headstock

2. Special-type

•   Designed for specific milling operations

3.  Knee-and-column-type

•   Relationship between cutter height and work controlled by vertical movement of         table.

Manufacturing-Type

Used primarily for quantity production of identical parts •Distinctive features

•Automatic cycle of cutter and work approach

•Rapid movement during non-cutting cycle

•Automatic spindle stop.

Manufacturing-Type

Two common types

•Plain manufacturing type

•Small plain automatic knee and column type.

Plain Manufacturing Type Milling Machine

  

Special-Type Machines 

•Designed for individual milling operations. •Used for only one particular type of job.

•Completely automatic

•Employed when hundreds or thousands of similar pieces are to be machined.

Machining Centers

•Capable of handling wide variety of work all in one setup.

•Straight and contour milling, drilling, reaming, tapping, and boring

Capable of high production rates while still maintaining high degree of accuracy.

•Rugged construction, reliable controls

•Anti-backlash ball screws.

Knee-and-Column-Type
Milling Machines

Machines in this class fall into three categories: •Plain horizontal milling machine.

•Universal horizontal milling machines.

•Vertical milling machines.

Universal Horizontal
Milling Machines

•         Difference from plain horizontal machine is addition of table swivel housing.

•         Located between table and saddle.

•         Permits table to be swiveled 45º in either direction in a horizontal plane.

•       Used for milling of helical grooves in twist drills, milling cutters, and gears.

 Universal Horizontal Milling Machine

 

Milling Machine Parts

•         Base

•         Gives support and rigidity to machine.

•         Acts as reservoir for cutting fluids.

•         Column face

•         Precision-machined and scraped section used to support and guide. knee when moved vertically.

•         Knee

•         Houses feed mechanism.

•         Attached to column face and moved vertically.

•         Saddle

•         On top of knee

•         Moved in or out by

   Means of cross feed hand wheel (manually or automatically)

•         Swivel table housing

•         Fastened to saddle on universal milling machine.

•         Enables table to be swiveled 45º either side of center line.

•         Table

•         Rests on guide ways in saddle and travels left and right

•         Supports vise and work

•         Cross feed hand wheel

•         Used to move table in and out

•         Table hand wheel

•         Used to move table left and right

•         Feed dial

•         Used to regulate table feeds

•         Spindle

•         Provides drive for attachments, arbors, cutters

•         Over arm

•         Provides for correct alignment and support of arbor and various attachments

•         Can be adjusted and locked in various positions.

•         Arbor support

•         Fitted to over arm and can be clamped

•         Aligns and supports various  attachments

•         Elevating screw

•         Gives upward or downward movement to knee and table (manually or automatically)

•         Spindle speed dial

•         Set by crank used to regulate spindle speed.

Backlash Eliminator

•         Eliminates backlash (play) between nut and table lead screw

•         Permits operation of climb (down) milling

•         Two independent nuts mounted on lead screw

•         Nuts engage common crown gear which meshes with rack

•         Axial movement of rack controlled by backlash eliminator engaging knob on front of saddle

•         Turning knob in, nuts forced to move along lead screw in opposite directions

Machine Backlash Eliminator