The minimum tension of the driving spring should be so large that if
the first finger hole is loaded with a weight = 80 g and rotated towards
the finger stop (position a, fig. 43), the finger wheel should return freely
to its normal position (position b, fig. 43).
The maximum tension should not be so large that when the last finger
hole is loaded with a weight = 150 g and rotated 6 - 10 mm past the
finger stop (position a, fig. 44) the finger wheel should be pulled by the
weight towards the finger stop.
Finger wheel
The finger wheel should be mounted so that the spring housing studs
(a, fig. 45) are properly in position. Otherwise the spring housing will be
damaged when the nut is tightened.
The finger wheel must not hide any marks on the base plate.
Stand-switch plunger
(Fig. 45)
The edge (c) of the stand-switch (2) shaft should be well levelled so that
the stand-switch plunger will slide easily into the main shaft (spindle)
(4). The edge of the cap should be at least 0.5 mm inside the edge of the
finger wheel (3).
Return spring
(Fig. 45)
The spring (5) should lie inside the guide (supporting) edge (d) of the
finger wheel and exert such a tension that a pressure of 25 ±5 g is
required to actuate the plunger.
Springset vertical
(Fig. 46)
The mounting hole of the vertical (1) should be concentric with
corresponding hole in the insulating washer (2).
Stand-switch plunger assembly
(Figs. 45 and 47)
The springset vertical should be mounted so that the stand-switch
plunger assembly is symmetrical in relation to the stand-switch
plunger's cone (taper). The distance between the lower edge of the
stand-switch plunger's cone (taper) and the contact springs is adjusted
in accordance with fig. 45.
Check that the contact springs are fully actuated when the assembly is
on a level surface and that they are wholly unactuated when the
assembly is lifted.
The contact springs should be fully actuated when the front edge of the
assembly is lifted as in fig. 47.
Impulse springs
(9, fig. 38 and 48)
The sliding surfaces should be smooth and free from cracks.
The springs are adjusted so that the impulse cams engage midway
between the impulse springs and at a depth indicated in fig. 50.
Contact pressure and distance are adjusted as in fig. 48 in such a way
that the movement of the spring is the same.
Short circuiting groups
(Fig. 49) DBY 012 earlier type
When the dial returns to home position, springs 1 and 3 should
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