Q.27 Describe the terry mechanism with variable sweep of sleyAns:- This terry motion used for creating gaps between picks , the system of fast reed and variable swing in sley is used. This type of terry pile motion is designed to withdraw the sley backward for a short distance for making consecutive loose beat-up and for making the full beat-up on the fast pick.Later on due to high speed shuttle less looms the mechanism is slightly changed

(A). HOLDEN TERRY MECHANISM

OBJECT:-It is used on conventional shuttle looms to give variable sweep to the sley.PRINCIPEL:-It is based on the fast reed and variable swing in the sley.

fig.22.1

CONST. AND WORKING :-The crank connection to the sley slightly modified. The pin in the arm is located freely in the slotted bracket that is attached to the sley. By rising a lowering the position of the pin in the slot the throw of the sley is altered so as to impart full and loose beat up respectively, the vertical sliding movement of the connecting pins is governed by means of terry tappets mounted on the counter shaft of the loom. Which act upon weighted treadle lever fulcrum at the stud.The raising and; lowering of the treadle lever is carried out by the terry tappet depending upon the order in which the loose and the full beat up is required. And this action is transmitted to the crank arm by the means of link. The dead weight and the spring are responsible for the reversing action of the treadle that keeps the connecting pin in the upper limit, so as to impart full beat up,

SETTING OF DIFFERENT LOOP HEIGHT:-By changing the point of connection between link and treadle lever. The variation in the stroke in the loom sley may be regulated to produce loop of different length.

SETTING FOR DIFFERENT TYPE OF TERRY:-The movement of the; loom sley with respect to the loose and the full beat up may be change by fitting different tappet.NOTE:-one thing to be noted the reed remain fixed in the loom so it gives all advantage of fast reed loom.

LOOM CRANK

CONNECTING ARM

CONNECTING PIN

SLOTTED BAR

SLEY SWORD

WEIGHTEDED TREADLE LEVER

TAPPET OR CAM

CONNECTED ROD

DEAD WEIGHT

SPRING

CRANK SHAFT

BOTTOM SHAFT

FULCRUM OF F

After the invention of shuttle less loom and change in beat up mech., Sulzer brothers had produced the variable swing to sley.

(B).TERRY MOTION WITH VARIABLE SWEEP OF SLEY

OBJECT :-In this mechanism the loop formation is done by the shorting of the sley movement that forms the gap b/w the fell of the cloth and loose picks.

Fig.22.2

CONSTRUCTION:-The reed is fixed on the sley, that is fast reed, the sley sword is locked about its fulcrum on L shape lever, B1 and B2 controlled the action of L shape lever. The motion from B1 and B2 transmitted to the sley with the help of triangle lever. Triangular lever is connected to control gear sweep for sley which decide the loop height, which in turns connected to lever with antifriction on control cam. The shape of pile control cam has been different for different pile weave repeat.

WORKING:-This mechanism used on shuttle less loom which is used matched cam beat up. It’s also preferred as conjugate cam beat up mechanism. The bigger profile of D1 when an act on B1 pushes the sley at back center position. The construction of attached cam profile is construct in such a way that large profile of D1 face be B1 and at same movement smaller profiles of D2 face by B2 that’s why it is known as matched cam. When D2 presses the antifriction bowl B2 reed moves for beat up. Smaller profile of pile control cam causes the L shape lever fulcrum to be pulled in direction of arrow thus terminating the reed at a distance from fell of the cloth by arrow thus terminating bowl B2 from beat up cam D1.

SETTING FOR LOOP HEIGHT:- By changing the teeth of the control gear we can change the loop height up to certain limit.

PILE CONTROL CAM

CONTROL GEAR

FULCRUM

B2 ANTIFRICTION BOWL

D2

LEVER

B1

BEATUP CAM

D1

TRIANGULAR LEVER

L SHAPE LEVER

ANTIFRICTION BOWL

SLEY

REED

SETTING FOR DIFFERENT TERRY WEAVE:- By changing the shape of the pile control cam we can make different terry weave (3, 4, 5, 6 pick terry)The bigger profile of the cam represents the fast pick and smaller profile of the cam will represent the loose pick.

Submitted by:-

Rakesh kumar Dabkeya