“Develop success from failures. Discouragement and failure are two of the surest stepping stones to success.”
Unit - V Automation in Binding
The machine used for cutting and trimming the sheets or boards is called as single knife guillotine or paper cutting machine.
A programmable cutting machine is a power operated machine with automated features which facilitate and speed up the work. One of the salient features is the ease and perfection in label cutting.
The important parts of the programmable cutting machine are bed, clamp, knife, back gauge and safety devices.
The bed is the base platform of the machine made of steel. One third (1/3) length of the bed is in front of the knife and two thirds (2/3) is behind the knife. The width of the bed is actually, the size of the machine. On the surface of the bed air blast marbles are provided at equal intervals to facilitate the easy movement of the paper pile. In some latest machines, to increase the output and speed up the work, hydraulic lifting rams are provided on both the sides of the table.
Back gauge is the important part of the machine. The squareness and perfection of the cutting depends upon the proper positioning of the back gauge during assembly. It must stand exactly in right angle to the bed and move to and fro exactly parallel to the knife.
In programmable cutting machine, the back gauge movement is performed by a motor which is controlled by the programme. With the help of the computer electronic system, the movement of the back gauge, lowering down of the clamp and the knife are activated fully automatically.
It is a square block of heavy steel used to give pressure over the stock being cut. It is essential to have firm pressure on the stock while cutting. Otherwise the work will be affected with rough edges, unevenness in size tec. The clamp is pressed down or moved up with the help of hydraulic mechanism. The hydraulic mechanism gives the required amount of pressure for accurate cutting. The clamp can also be lowered down by a foot operated pedal to adjust the pile of the paper according to the cutting marks printed on the paper. While cutting operation is performed, the clamp is activated automatically and it presses the pile before knife strikes the paper.
Knife blade is made of medium carbon steel, chrome and other alloys. The knife is fixed to a knife beam with screws. The knife beam is moved by an eccentric action with the help of a motor which is controlled by the computer electronics. For this we have to press two buttons. Electronically controlled machine activates the knife automatically as per preset programme.
The accidents occurred in printing industry are mostly because of this most dangerous risky machine. That is why the cutting machine is automated with safety devices. The safety devices used are
These are automatically activated when the knife movement starts and thrust away the operator from the cutting area.
These are brackets which cover the whole cutting area and are to be closed before starting knife action.
These are fixed on both sides of the cutting area. Any action by the body of the operator that breaks the beam of the light will halt the knife at once.
It engages both the hands of the operator to activate knife. Hence there are less chances of accidents.
Folding can be generally classified as manual and mechanical folding. Manual folding is done manually with help of bone folder. Mechanical folding is done with the help of folding machine.
In the process of mechanical folding (or) a folding machine, two techniques are used namely,
A buckle folding station consists of three rollers and a buckle plate. The first two rollers are arranged vertically above one another. These are called as forwarding rollers. The forwarding rollers carry the incoming sheet into the buckle plate until it reaches an adjustable feed guide stop.
As the lead edge of the sheet strikes the feed guide stop, the sheet continues to be fed into the buckle plate creating a buckle in the space between the three rollers. The buckle created is grabbed by the contra rotating rollers and the fold is formed as the sheet passes through them.
Each folding station can fit up to six buckle plates arranged alternatively above and below.
Knife folding uses a vertically moving knife and two rollers rotating in opposite directions. The sheet goes and stops at
the sheet stop. At this point, the knife descends vertically and plunges (or) inserts the sheet
through the rollers. As the sheet passes through the rollers, the sheet is creased and the fold is formed.
Only one folding knife is to be found in any folding station. For every subsequent fold, it is necessary to have a further knife folding station at right angle to the preceding one.
It is the simplest but very important machine in binding department. Most of the works are done using wire stitching machine because it is the quickest and cheapest method of binding. The wire stitching machine consists of the following parts.
It is present at the top of the machine. The reel of wire is wound around a steel roller. During the machine running, the reel is unwound from this roller. The wire is made of copper coated around steel wire.
The wire straightener consists of two steel rollers. The wire is made straight when the wire passes between these two rollers.
The cutter block cuts the wire according to the thickness of the book. For this we have already set the cutting length according to the thickness of the book. False setting may lead to improper stitching.
The legs of the staple are then formed by bending the wire down on either side of the block. Then the driver drives the “U” shaped staple into the book kept on the bed.
The book to be stapled is placed on the bed or saddle. The bed can be adjusted according to the style of stitching. The saddle can be adjusted for both side and saddle stitching`` .
The clenchers underneath the bed bends the legs of the staples to close the stitch.
The spine glued books are stacked in the hopper. The fore edge of the book is kept down. Then the book is transferred in between two milled rounding rollers. There are sahpers. One is at the spine side and the other one is at the fore edge of the book. The rounding rollers move the book up and down. Due to this the shapers make the book rounded by pressing the end sections towards the fore edge. Then the rounded book is moved to the backing station. Here there is a wiper. It moves across the spine side of the book and hammers hard blows. Due to this the book gets backed at the spine. Finally the book is delivered.
revolving Conveyor belt
In gathering machine, the piles of different sections of a book are placed in separate hoppers. The sections are placed in consecutive order. The bottom section from each hopper is pulled by suckers. The suckers give the section to a gripper arm. The gripper takes the section and drops it on a revolving conveyor belt. When the dropped section reaches the next station or hopper, the next section is dropped over this section. Finally the book is collected. This is transported to another conveyor belt, which delivers the gathered sections to the delivery stacker.