1 the principle of worm gear reducer
The worm and worm gear drive is evolved from helical gears with staggered shafts. The gear teeth of the pinion are wound more than a week on the cylindrical surface, so the pinion is shaped like a screw, called a worm. The big gear is called the worm gear. In order to improve the meshing condition, the cylindrical surface of the worm wheel dividing bus is changed to be arc, which partly encloses the worm, and the worm hob with the same shape and parameters of generating machining worm tooth profile, such as line contact, can transmit greater power.
Characteristics of worm and worm gear drive:
First, it is a special kind of crossed helical gear drive with a stagger angle of sigma = 90 degrees, little Z1, and a general Z1 = 1~4;
Second, it has some characteristics of spiral transmission, worm is equivalent to screw, worm gear is equal to nut, worm gear partly understands worm.
2 types of worm drive
According to the worm shape difference can be divided:
1. cylindrical worm drive - common cylindrical worm and worm gear reducer (Archimedes worm, involute worm, normal straight worm, cone thread worm) and circular arc worm.
2. enveloping worm drive
3. worm drive
Cone and worm movement
Characteristics of 3 worm drive
Large transmission ratio, compact structure
The worm gear reducer is stable and noiseless
The transmission efficiency is low and the wear is severe
The axial force of worm is larger, which makes the bearing friction more expensive.
Application of 4 worm drive
As worm gear reducer worm gear drive has the above characteristics, it is often used for two axis staggered, transmission contrast, transmission power is not too large or stop work place. In order to improve transmission efficiency, Z1 = 2-4 is often used to transfer transmission efficiency. In addition, because when the gamma 1 is small, the transmission has self-locking property, so the utility model is usually used as a safety guard in hoisting machines such as hoisting machines. It is also widely used in machine tools, automobiles, instruments, metallurgical machinery and other machines or equipment;
The use of worm gear reducer, worm drive, large transmission ratio, labor saving features, and its self-locking function, widely used in lifting machinery.
Single stage worm gear reducer
The worm worm drive with respect to the difference position of the worm gear is divided into upper and lower worm worm drive.
5 worm gear structure
1. worm structure:
Worm gear reducer worm usually with the shaft as a whole, choose the car or milling system
2. worm gear structure:
The worm used hybrid structure, composed of the crown and the tooth core. The main points of connection are forging connection, interference fit and bolt connection. The structural differences are shown below. The worm gear is only selected in low speed and light load.
Worm gear reducer use, installation and maintenance
1, according to the actual requirements of a variety of installation forms, six surfaces can be installed.
2 the installation must be firm and reliable.
Among the organizations of the 3 original motivation, reducer should be carefully in the error of not more than the allowable compensating coupling.
4, after the installation of hand rotation, you must be flexible, no card lag phenomenon.
Two, the use of lubricant replacement
1, the first use or replacement of worm gear, running 150-400 hours after the replacement of lubricating oil, oil change cycle is less than or equal to 4000 hours.
2 regularly check the weight and quality of the oil, keep enough lubricating oil, and replace the oil mixed with impurities or spoiled oil in time.
3, the amount of oil must be required by the table, different grades of oil prohibited mixing, the same grade and viscosity of different oils allow mixed use.
4 oiling quantity Schedule 1, oil according to schedule 2
5 the working environment temperature of the reducer is -40 ~ +40 centigrade. When the ambient temperature is below 0 degrees, the lubricant must be heated to above 0 degrees or a low freezing point oil before starting.
Three, matters needing attention:
1 do not hammer the outer housing of the reducer in order to avoid damage.
2, regular maintenance, installation foundation, seals, transmission shaft and so on is normal.
3, if normal use, the maximum temperature of lubricating oil should be less than 85 degrees centigrade. When the temperature rise of oil temperature is abnormal and abnormal noise occurs, it must be checked and stopped immediately. After troubleshooting, it can continue to be used.
4 replacement of new spare parts must be run and load test after the formal use.
Worm gear reducer type classification
CW series circular cylindrical worm reducer (GB9147 - 88), WH series circular cylindrical worm reducer (JB2318 - 79), WD type cylindrical worm reducer (JB/ZQ 4390-79)
WC cylindrical worm reducer, WXJ cylindrical worm reducer, WCJ cylindrical worm reducer
WSJ cylindrical worm reducer, WS cylindrical worm reducer (JB/ZQ 4390-97), CW series circular cylindrical worm reducer (JB/T 7935-1999)
TP type planar enveloping worm reducer, PW type planar two enveloping hourglass worm reducer (GB-T16449-1996), HW profile worm gearing (JB/T 7936-1999)
SCW shaft mounted circular cylindrical worm reducer (JB-T6387-1992), ZC1 type double worm gear and gear worm reducer (JB-T7008-1993), KW conical cylindrical worm gear reducer (JB/T 5559-91)
WP, WD worm reducer, SKWU type shaft mounted conical worm reducer, BRV series variable speed worm reducer
WR worm reducer, WDH worm gear reducer, WS type worm gear reducer
WL type multi purpose worm gear reducer, WX worm gear reducer, QT worm gear reducer
RD type two enveloping worm gear reducer, WQ type cylindrical worm reducer, DKWU-F cone shaped worm reducer
WHZ worm gear reducer, multi surface mounted circular cylindrical worm reducer, CWG double stage worm gear reducer
CWS circular arc cylindrical worm reduction