![]() ![]() The work surface is also prevented from any damage due to dragging. On the return stroke a slight frictional drag of the tool on the work lifts the block out of the clapper box a sufficient amount preventing the tool cutting edge from dragging and consequent wear. ![]() On the forward cutting stroke the clapper block fits tightly to the clapper box to make a rigid tool support. The tool post is mounted upon the clapper block. The two vertical walls on the apron called clapper box houses the clapper block, which is connected via hinge pin. ![]() Apron consisting of clapper box, clapper block and tool post is fitted upon the vertical slide by a screw. The amount of feed or depth of cut can be controlled by a micrometer dial on the top of the down feed screw. By rotating the down feed screw handle, the vertical slide carrying the tool gives down feed or angular feed movement while machining vertical or angular surface. The different parts of tool head of shaper are apron clamping bolt, clapper box, tool post, down feed, screw micrometer dial, down feed screw, vertical slide, apron washer, apron swivel pin, and swivel base. Tool head The tool head of a shaper performs the subsequent functions (1) It holds the tool rigidly, (2) It gives vertical and angular feed motion of the tool, and (3) It permits the tool to have an automatic relief during its return stroke. Ram is connected to the reciprocating mechanism contained within the column. Ram It is the reciprocating part of the shaper, which reciprocates on the guide ways provided above the column. It is bolted to the saddle and receives crosswise and vertical movements from the saddle and cross rail. Table The table is a box like casting having T -slots both on the top and sides for clamping the work. Crosswise movement of the saddle by rotation the cross feed screw by hand or power causes the table to move sideways. Saddle The saddle is located on the cross rail and holds the table on its top. This screw actuates the table to move in a crosswise direction. ![]() A horizontal cross feed screw is fitted within the cross rail and parallel to the top guide ways of the cross rail. It consists of mechanism for raising and lowering the table to facilitate different sizes of specimen by rotating an elevating screw which causes the cross rail to slide up and down on the vertical face of the column. It is fixed on the front vertical guide ways of the column. Cross rail Cross rail of shaper has two parallel guide ways on its top in the vertical plane that is perpendicular to the rail axis. Two accurately machined guide ways are provided on the top of the column on which the ram reciprocates. Column The column is a box shaped casting mounted upon the base. The base may be rigidly bolted to the floor of the shop or on the bench according to the size of the machine. It holds all other parts of the machine, which are fixed over it. Hand wheel a Swivel clamp ae L locking clapīase It is rigid and heavy cast iron body to resist vibration and takes up high compressive load. (a) Grooved block (b) Dove tail sige (c} Guide gid (4) V-BlockĬutting action and functioning of clapper box The time taken throughout the idle stroke is less as compared to forward cutting stroke and this is obtained by quick return mechanism. The feed is given to the workpiece and depth of cut is controlled by moving the tool downward towards the workpiece. The backward stroke remains idle and no cutting takes place throughout this stroke. In a standard shaper, cutting of workpiece takes place during the forward stroke of the ram. The ram reciprocates and cutting tool mounted in tool holder moves forward and backward over the specimen. The table can be supported at the outer end. The workpiece is stiffly held in a vice or clamped directly on the table. Working Principle of Shaper A single point cutting tool is held in the tool holder that is mounted on the ram. A shaper is used to produce flat (plane) surfaces by single point cutting tool similar to a lathe tool. Modern shapers can also produce contoured surface. In general, the shaper can produce any surface consisting of straight-line elements. These surfaces can be horizontal, vertical, or inclined. It can also make slots, grooves and keyways in the shafts. It is needed primarily for the production of flat surfaces. Download shaper machine and machine tool and more Mechanics Lecture notes in PDF only on Docsity!Shaper Machine Introduction Shaper is a reciprocating type of machine tool in which the ram moves the cutting tool back and forth in a straight line. ![]()
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