Classification of tappet shedding and mechanism

 Classification of tappet shedding and mechanism:

Tappet shedding is one kind of shedding mechanism. Based on positive and negative shedding w can divide into two types. 

1. Positive tappet shedding 

2. Negative tappet shedding

Below I have described elaborately about above two types of shedding. 

1. Positive tappet shedding: In positive tappet shedding there is no need for any kind of excess mechanism to up and down the heald shaft. These types of tappet are as below: 

a)Woodcrafts section tappet

b) Oscillating tappet 

c) Neutrals tappet

d) Scroll tappet

2. Negative shedding mechanism: The excess mechanism like a pulley, stock, and bowl, spring, or dead weight need to reverse the direction of movements in healds. These types of tappets are as below. 

1. Ordinary plain and twill shedding tappet

2. Jamieson's tappet

3. Barrel tappet

Tappet shedding mechanism : 

During plain weave need to divide warp yarn into two sets and a pair of warp yarn need to take an even number of warp yarn in one-row head and an odd number of warp yarn need to take throughout the other heald shaft. The upper part of the head is attached to the top roller by cord and strap and the down part is attached to the end of travel.  Between the two travel, there are two anti-friction bowls and the other end has a fulcrum. Anti-friction bowl is adjacent to two tappets. Both tappets get energy from the bottom shaft and always be opposite sites. 

Working procedure: When the bottom shaft moves and is round then the tappets are also round. Both tappets are set to the opposite of one another so when one tappet's nose is on the upper side then another tappet's nose is on the underside. Which tappets nose is in an under position that will give pressure on the anti-friction bowl and the tradel lever will be down and with the help of the rod and cord, the heald shaft will be down. As heald shafts, another side is attached with a top roller so if one-row heald shaft is down then another heald shaft is up. Due to this mechanism, it makes shed.