Linear superimpositioning of a circular path
Application
You can linearly superimpose a movement programmed in the working plane, thereby creating a spatial movement.
If, for example, you superimpose a circular path, you create a helix. A helix is a cylindrical spiral, such as a thread.
Related topics
- Linear superimpositioning of a circular path that is programmed with Cartesian coordinates
Requirements
The path contours for a helix can only be programmed with a circular path CP.
Description of function
A helix is a combination of a circular path CP and a linear motion perpendicular to this path. You program the circular path CP in the working plane.
Helices are used in the following cases:
- Large-diameter internal and external threads
- Lubrication grooves
Dependencies of different thread shapes
The table shows the dependencies between machining direction, direction of rotation and radius compensation for the different thread shapes:
Internal thread | Work direction | Direction of rotation | Radius compensation |
---|---|---|---|
Right-handed | Z+ | DR+ | RL |
Z– | DR– | RR | |
Left-handed | Z+ | DR– | RR |
Z– | DR+ | RL |
External thread | Work direction | Direction of rotation | Radius compensation |
---|---|---|---|
Right-handed | Z+ | DR+ | RR |
Z– | DR– | RL | |
Left-handed | Z+ | DR– | RL |
Z– | DR+ | RR |
Programming a helix
Define the same algebraic sign for the direction of rotation DR and the incremental total angle IPA. The tool may otherwise move on a wrong path.
To program a helix: | ||
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Example
This example includes the following default values:
- M8 thread
- Left-handed thread miller
The drawing and the default values allow deriving the following information:
- Internal machining
- Right-hand thread
- RR radius compensation
The derived information requires the machining direction Z–.
Dependencies of different thread shapes
Specify and calculate the values below:
- Incremental total machining depth
- Number of thread grooves
- Incremental total angle
Formula | Definition |
---|---|
The incremental total machining depth IZ results from the thread depth D (depth) and from the optional thread run-in values RI (run-in) and thread run-out values RO (run-out). | |
The number of thread grooves n (number) results from the incremental total machining depth IZ divided by the pitch P (pitch). | |
The incremental total angle IPA results from the number of thread grooves n (number) multiplied by 360° for one complete revolution. |
11 L Z+1,25 R0 FMAX | ; Pre-position in the tool axis |
12 L X+4 Y+0 RR F500 | ; Pre-position in the plane |
13 CC X+0 Y+0 | ; Activate the pole |
14 CP IPA-3600 IZ-12.5 DR- | ; Cut the thread |
Alternatively, you can also program the thread with a program section repeat.