HEIDENHAIN TNC 306 Technical Manual - Manual (Page 145)

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TNC 406/TNC 306 3 Servo positioning of the NC-axes 4-45
3.4 Contouring behavior in corners
3.4.1 Radial acceleration
In addition to the normal acceleration (MP1060) there is also a machine parameter for radial
acceleration (MP1070).
The machine parameter limits the feed for circular movements according to the following formula:
v = r [m] · MP1070 [m/s 2 ] v = feed rate for circular movements [m/s]
r = radius [m] (cutter mid-point contour)
It is recommended that a value is entered which is 50–100% of that in MP1060 (Acceleration). If the
programmed feed is lower than that above, then the programmed feed will be used.
MP1070 Radial acceleration
Entry value: 0.001 to 3.0 [m/s
2 ]
3.4.2 Constant feed rate in corners
Machine parameter MP7460 defines the angle which can still be traversed with constant feed rate.
This machine parameter is effective for corners without a radius compensation, for internal corners
it is also effective with a radius compensation.
MP7460
The permissible size of the angle depends on the drives in the machine.
Realistic values are 5° to 20°.
The resulting path is as follows:
α
α = Change of axis movement direction
s
a
= Servo lag
Axis standstill
Path when MP7460 <
α
Path when MP7460 >
α
s
a
MP7460 Constant feed rate in corners
Entry value: 0.001 to 179.999°