What are the many square pieces on a Chinese gate?

It is a kind of structural component used to fix the door, initially two door hairpins can play a role in fixing the door, and later evolved into a kind of decorative components, to four mostly. I have two pictures here to show you its structure, the door hairpin inside and connected to the pillar, used to pin the pillar on the upper sill, the upper end of the door axle and then installed in the pillar, so that the door can be fixed. Chinese New Year is the most important festival in people's daily life. Because at this time, the whole family will get together to clean up, put up spring couplets, stick the lucky words, in order to welcome the new year. So at this time, have people ever paid attention to why to stick the lucky words, according to the requirements of the traditional culture to stick it? Why do you want to stick the word "Fu" in the Spring Festival, is a long-established folk custom. According to the "Dream sorghum record" records: "year's day in the near, mat store department store, painting door god peach symbols, welcome spring card child?"; "the common people's family regardless of whether they have to pay a lot of money, but also to pay a lot of money, but also to pay a lot of money. ; "the common people, regardless of the size of the family, all cleaned the door, to dust, net household, change the door god, hanging Zhong Kui, nail peach charm, stick the spring card, worship the ancestors". The text of the "sticker" that is written on red paper "Fu".