Planer Machine
PLANER
In a planer, the work which is supported on the table reciprocates over the stationary cutting tool and the feed is provided by the lateral movement of the tool.
Parts of Planer Machine
Following are the six main parts of the planer machine:
- Bed
- Table
- Housing or Column
- Cross rail
- Tool head
- Driving and Feed Mechanism
Bed
- The bed of a planer is a box-like casting having cross ribs. It is very large in size and heavy in weight and it supports the column and all other moving parts of the machine.
- The bed is made slightly longer than twice the length of the table so that the full length of the table may be moved on it.
- Three or more guideways may be provided on a very large wide machine for supporting the table.
- The guideways should be horizontal, true and parallel to each other.
- The ways are properly lubricated and in modern machines oil under pressure is pumped into the different parts of the guideways to ensure a continuous and adequate supply of lubricants.
Table
- The table supports the work and reciprocates along with the ways of the bed.
- The planer table is a heavy rectangular casting.
- T-slots are provided on the entire length of the table so that the work and work holding devices may be bolted upon it.
- At each end of the table, a hollow space is left which acts as a trough for collecting chips. Long works can also rest upon the troughs.
- In a standard planer, the table is made up of one single casting but in a divided table planer there are two separate tables mounted upon the bedways.
- Hydraulic bumpers are fitted at the end of the bed to stop the table from overrunning giving cushioning effect.
- In some machines, if the table overruns, a large cutting tool bolted to the underside of the table will take a deep cut on a replaceable block attached to the bed, absorbing the kinetic energy of the moving table.
Housing
- The housings also called columns or uprights are rigid box-like vertical structures placed on each side of the bed and are fastened to the sides of the bed.
- They are heavily ribbed to take up severe forces due to cutting.
- The front face of each housing is accurately machined to provide precision ways on which the cross rail may be made to slide up and down for accommodating different heights of work.
- Two side-toolheads also slide upon it. The housing encloses the Crossrail elevating screw, vertical and crossfeed screws for tool heads, counterbalancing weight for the Crossrail, etc. These screws operated either by hand or power.
Cross rail
- The Crossrail is a rigid box-like casting connecting the two housings. This construction ensures the rigidity of the machine.
- The Crossrail may be raised or lowered on the face of the housing and can be clamped at any desired position by manual, hydraulic or electrical clamping devices.
- The Crossrail when clamped should remain absolutely parallel to the top surface of the table, i.e. it must be horizontal irrespective of its position.
- Usually, two toolheads, are mounted upon the Crossrail which are called railhead.
- The Crossrail has screws for vertical and crossfeed of the toolheads and a screw for elevating the rail. These screws rotated either by hand or by power.
Tool-head
The tool head of a planer is similar to that of a shaper both in construction and operation. The important parts of a tool head are:
- Saddle
- Swivel base
- Vertical Slide
- Apron
- Clapper box
- Clapper block
- Toolpost
- Down feed screw
- Apron clamping bolt,
- Apron swivelling pin
- Mechanism for cross and down-feed of the tool.
Types of Planer Machine
Following are the five types of planer machine:
- Standard or Double housing type planer machine
- open side type planer machine
- Pit planer machine
- Edge or plate-type planer
- Divided table planer
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