Kitagawa MR250RAE13, Инструкция по эксплуатации

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20
10. Adjustment of Backlash between Worm Wheel and Worm
Gear
The amount of backlash has been adjusted to the appropriate range at time of the
shipment from the factory. However, if it becomes necessary, excessive backlash between
the precisely machined double-lead worm and worm wheel can be eliminated easily with
two slightly different inclined leads provided on the worm gear. Appropriate amount of
backlash between the worm and worm wheel is shown below. The figures apply only when
the unit is cold. The amount of backlash will be affected by thermal expansion when the
unit warms up during operation.
If the amount of backlash is too small, it may cause a heat
sei
ｚ
ure of the worm and worm wheel.
○
Optimum values of backlash
MODEL MR(M)
120
MR(M)
160
MR(M)
200
MR(M)
250
MR(M)
320
MX(M)
160
Backlash in Circular
Length of Table O.D.
（
μ m
）
12
～
37 13
～
39 13
～
38 13
～
41 14
～
41 14
～
41
Backlash in seconds 39
～
118 33
～
98 26
～
78 22
～
68 18
～
53 35
～
105
If it is necessary to adjust the amount of backlash, measure the backlash using the
following procedure
：
10-1. Measuring the Backlash of the Worm Gear [See Fig.2]
1) Set a dial gauge on the side face of the guide block on the top surface of the table.
2) Turn the table slowly by using the tap on the surface of the table as shown in Fig.2. And
read the value of the dial gauge when tooth of the worm wheel makes contact with a
worm shaft. At this time, the rotating torque added to the table is as follows. Then,
rotate the table on the same conditions to the opposite direction. The difference of
these measurements is the amount of backlash.
MODEL MR(M)
120
MR(M)
160
MR(M)
200
MR(M)
250
MR(M)
320
MX(M)
160
Torque added to table T
（
N
・
m
）
11 15 17 26 30 15
3) The above measurements should be conducted at four different points by rotating the table
90 degrees at a time. Compare the readings with the correct amount of backlash shown
above. If the reading is out of the range specified, take the following procedures to adjust
the backlash so that the minimum reading is within the correct range specified above.
CAUTION