Primena linearne vodilice u alatnim mašinama
Sistem vodilice omogućava alatnoj mašini da postigne brzu brzinu pomaka. U slučaju iste brzine vretena, brzi pomak je karakteristika linearnih vodilica. Linearne vodilice, kao i ravne vodilice, imaju dva osnovna elementa; jedan kao vodič je fiksni element, a drugi je pokretni element. Pošto je linearna vodilica standardna komponenta, ona je za proizvođače alatnih mašina. Jedino što treba učiniti je obraditi ravan montažne šine i podesiti paralelnost šine. Naravno, da bi se osigurala tačnost alatne mašine, neophodna je mala količina struganja ležaja ili stuba. U većini slučajeva, instalacija je relativno jednostavna.
Compared with flat guide rails, the cross-sectional geometry of linear guide rails is more complicated than that of flat guide rails. The reason for the complexity is that grooves need to be machined on the guide rails to facilitate the movement of sliding elements. The shape and number of grooves depend on the machine tool to complete. Function. For example: a guide rail system that bears both linear force and subversive moment is compared with a guide rail that only bears linear force. The design is very different.
There is no intermediate medium between the moving element and the fixed element of the linear guide, but a rolling steel ball. Because the rolling steel ball is suitable for high-speed motion, has a small friction coefficient and high sensitivity, it can meet the working requirements of moving parts, such as the tool holder and carriage of the machine tool. The basic function of the fixed element (guide rail) of the linear guide system is like a bearing ring, and the bracket for mounting the steel ball is shaped like a "v". The bracket wraps the top and both sides of the rail. In order to support the working parts of the machine tool, a set of linear guide has at least four supports. Used to support large working parts, the number of brackets can be more than four.
When the working parts of the machine tool move, the steel balls circulate in the groove of the bracket, and the wear of the bracket is distributed to each steel ball, thereby prolonging the service life of the linear guide. In order to eliminate the gap between the bracket and the guide rail, the preload can improve the stability of the guide rail system and the preload can be obtained. It is to install an oversized steel ball between the guide rail and the bracket. The diameter tolerance of the steel ball is ±20 microns, with 0.5 micron increments. The steel balls are screened and classified and installed on the guide rails respectively. The size of the preload depends on the force acting on the steel balls. If the force acting on the steel ball is too large, the steel ball will withstand the preload for too long, which will increase the movement resistance of the bracket. There is a balance problem here; in order to improve the sensitivity of the system and reduce the movement resistance, the preload must be reduced accordingly, and in order to improve the movement accuracy and the retention of precision, it is required to have sufficient preload negative numbers, which are contradictory two. aspect.
If the working time is too long, the steel ball starts to wear out, and the preload on the steel ball starts to weaken, resulting in a decrease in the movement accuracy of the working parts of the machine tool. If you want to maintain the initial accuracy, you must replace the rail bracket, or even replace the rail. If the rail system has a preload effect. The accuracy of the system has been lost, and the only way is to replace the rolling elements.
Dizajn sistema vodilice teži da ima najveću kontaktnu površinu između fiksnog elementa i pokretnog elementa. Ovo ne samo da poboljšava nosivost sistema, već i sistem može izdržati udarnu silu koja nastaje povremenim rezanjem ili gravitacijskim rezanjem, širiti silu naširoko i proširiti nosivost. Područje sile. Da bi se to postiglo, postoje različiti oblici žljebova sistema šine vodilice, a postoje dva reprezentativna, jedan se zove tip Gedai (tip šiljastog luka), oblik je polu{0}}kružni nastavak, i kontaktna tačka je vrh; drugi je jedan je kružnog oblika, koji također može igrati istu ulogu. Bez obzira na vrstu strukture, postoji samo jedna svrha, a težiti tome da se čelična kuglica više kotrlja radijusa kontakta sa vodilicom (fiksni element). Faktor koji određuje karakteristike performansi sistema je: kako elementi kotrljanja dodiruju vodilicu, što je ključ problema.