Mechanical Project Milling Fixture

"For an optimist the glass is half full, for a pessimist it's half empty,

and for an engineer is twice bigger than necessary."

At: PAMS Engineering, Mysore

Conceptualize a basic fixture configuration through

analyzing all the information.

Outputs:-

Fixture type and complexity

Number of workpieces per fixture

Orientation of workpieces within fixture

Clamping surfaces

Locating surfaces

Generation of fixture layout is to represent the fixtureconcepts in a physical form.

outputs:-

Position of locators

Position of clamps

Position of supports, if any

Types of clamps

Type of locators

Type of supports

• Fixture element design is to create the solid models ina CAD system of the practical embodiment of theconceptual locators, clamps and supports.

Outputs: -

Detailed design of locators

Detailed design of Clamps

Detailed design of supports

Tool body design is to produce a rigid structure

carrying all the individual fixture elements in their

proper places.

Design specifications

Factory standards

Ease of use and safety

Economy

Information gathering and analysis.

Consideration of clamping & locating schemes.

Design of fixture body.

Principle purpose of a machining fixture is to locate the

workpiece surfaces for performing a machining

operation

Surfaces to be distinguished

Active surfaces

Supporting & locating surfaces

Clamping surfaces

Free surfaces

Clamp

Device for providing an invariant location with respect to anexternal loading system.

Requirements of locking elements

To provide a suitable locking for achieving the

stability of location.

To provide sufficient frictional effects without

causing undesirable effect

Easy to manipulate manually or otherwise

Quick acting so as to reduce time setting clamping

and simultaneous locating

Inexpensive

Orientation of locators

Clamping force should be directed towards supporting and locating elements on overhanging or thin sections of the workpiece

classification of Clamping Elements

Type 1: elements in which the elastic deformationincreases with clamping force Ex: screws, levers, camsetc..,

Type 2: elements in which the clamping force assumesa constant value independent of the elastic deformationat the contact surface. Ex: Fixtures operated withhydraulic and pneumatic pressure

To provide a suitable locking for achieving the

stability of location.

To provide sufficient frictional effects without

causing undesirable effect