FCGear InvoluteGear: Difference between revisions

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{{Properties_Title|computed}}
{{Properties_Title|computed}}


* {{PropertyData|dw}}: Ptch diameter (not changeable, is calculated automatically).
* {{PropertyData|dw}}: Pitch diameter (not changeable, is calculated automatically).


{{Properties_Title|gear_parameter}}
{{Properties_Title|gear_parameter}}


* {{PropertyData|beta}}: With the helix angle β a helical gear is created (positive value = rotation direction right, negative value = rotation direction left).
* {{PropertyData|beta}}: With the helix angle β a helical gear is created (positive value = rotation direction right, negative value = rotation direction left).
* {{PropertyData|clearance}}:
* {{PropertyData|clearance}}: The value is subtracted or added to the root diameter.
* {{PropertyData|double_gear}}: True = creates double helix gear; False = in conjunction with the helix angle β a helix gear is generated (see also the information in {{Emphasis|Note}})
* {{PropertyData|double_gear}}: True = creates double helix gear; False = in conjunction with the helix angle β a helix gear is generated (see also the information in {{Emphasis|Note}})
* {{PropertyData|head}}:
* {{PropertyData|head}}: Value of {{Emphasis|head}} * module = additional length of tip diameter.
* {{PropertyData|height}}:
* {{PropertyData|height}}: Value for the gear width.
* {{PropertyData|module}}: The {{Emphasis|module}} is the quotient of the pitch circle diameter and the number of teeth (see also the information in {{Emphasis|Note}}).
* {{PropertyData|module}}:
* {{PropertyData|numpoints}}:
* {{PropertyData|numpoints}}:
* {{PropertyData|properties_from_tool}}:
* {{PropertyData|properties_from_tool}}: If helix angle β is given and {{Emphasis|properties_from-tool}} is enabled, gear parameters are internally recomputed for the rotated gear.
* {{PropertyData|shift}}:
* {{PropertyData|shift}}:
* {{PropertyData|simple}}:
* {{PropertyData|simple}}: True = simplified display.
* {{PropertyData|teeth}}:
* {{PropertyData|teeth}}: Number of teeth (see also the information in {{Emphasis|Note}})
* {{PropertyData|undercut}}:
* {{PropertyData|undercut}}: True = Change of the tooth profile within the root diameter (see also the information in {{Emphasis|Note}}).


{{Properties_Title|involute_parameter}}
{{Properties_Title|involute_parameter}}


* {{PropertyData|pressure_parameter}}:
* {{PropertyData|pressure_parameter}}: For a standard gear, this pressure angle is fixed at 20° with backlash-free pairing of the teeth (see also the information in {{Emphasis|Note}}).


{{Properties_Title|tolerance}}
{{Properties_Title|tolerance}}
Line 81: Line 81:


* To use the double helical gearing ({{Emphasis|Properties → gear_parameter → double_helix}}), the helix angle β ({{Emphasis|Properties → Data → gear_parameter → beta}}) for the helical gearing must first be entered.
* To use the double helical gearing ({{Emphasis|Properties → gear_parameter → double_helix}}), the helix angle β ({{Emphasis|Properties → Data → gear_parameter → beta}}) for the helical gearing must first be entered.
* If there are several gears, pay attention to which gear is set to {{{Emphasis|reversed_backslash}}.
* If there are several gears, pay attention to which gear is set to {{Emphasis|reversed_backslash}}.
* Only change the {{Emphasis|pressure angle}} if sufficient knowledge of the gear geometry is available.
*
* Using ISO (International Organization for Standardization) guidelines, Module size is designated as the unit representing gear tooth-sizes. However, other methods are used too (Module (m): m = 1 (p = 3.1416), m = 2 (p = 6.2832), m = 4 (p = 12.566). If you multiply Module by Pi, you can obtain Pitch (p). Pitch is the distance between corresponding points on adjacent teeth.
* If the number of teeth is changed, the pitch diameter also changes ({{Emphasis|dw}}).
* Undercut occurs when the number of teeth of a gear is too small. An undercut leads to a weakening of the strength of the tooth!


==Limitations==
==Limitations==

Revision as of 17:21, 25 March 2020

This documentation is a work in progress. Please don't mark it as translatable since it will change in the next hours and days.
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FCGear InvoluteGear

Menu location
FCGear → Involute gear
Workbenches
FCGear
Default shortcut
None
Introduced in version
-
See also
FCGear CycloideGear

Description

This and the linked website(s) are under construction since 8.3.2020. I try to fill the content quickly in addition to my job. Therefore please have a little patience. @bavariaSHAPE

Due to the favourable meshing ratio and the relatively simple production, involute gearing is the most common tooth form in mechanical engineering. Gear wheels can be found wherever movement and force are to be transferred from one part to another. For example, they can be found in machines, cars, watches or household appliances. The movement is often transferred directly from one gear wheel to the other, but sometimes also via a chain. In addition, the direction of rotation can be changed. It is also possible to change a radial movement into a linear one via Involute Rack ( Create an Involute rack).

From left to right: Spur gearing, helical gearing, double helical gearing

Usage

  1. Switch to the FCGear Workbench.
  2. Invoke the command several way:
  3. Change the gear parameter to the required conditions (see Properties → Data below).

Properties

Data

Base

  • DataPlacement: Placement is the location and orientation of an object in space.
  • DataLabel: User name of the object in the Tree view.

computed

  • Datadw: Pitch diameter (not changeable, is calculated automatically).

gear_parameter

  • Databeta: With the helix angle β a helical gear is created (positive value = rotation direction right, negative value = rotation direction left).
  • Dataclearance: The value is subtracted or added to the root diameter.
  • Datadouble_gear: True = creates double helix gear; False = in conjunction with the helix angle β a helix gear is generated (see also the information in Note)
  • Datahead: Value of head * module = additional length of tip diameter.
  • Dataheight: Value for the gear width.
  • Datamodule: The module is the quotient of the pitch circle diameter and the number of teeth (see also the information in Note).
  • Datanumpoints:
  • Dataproperties_from_tool: If helix angle β is given and properties_from-tool is enabled, gear parameters are internally recomputed for the rotated gear.
  • Datashift:
  • Datasimple: True = simplified display.
  • Datateeth: Number of teeth (see also the information in Note)
  • Dataundercut: True = Change of the tooth profile within the root diameter (see also the information in Note).

involute_parameter

  • Datapressure_parameter: For a standard gear, this pressure angle is fixed at 20° with backlash-free pairing of the teeth (see also the information in Note).

tolerance

  • Databackslash: Backlash, also called lash or play, is the clearance between the teeths of two gears.
  • Datareversed_backslash: true = backlash decrease; false = backlash increase (see also the information in Note).

View

The parameter descriptions of the View tab will be found in Property editor, further below at Example of the properties of a PartDesign object.

Notes

  • To use the double helical gearing (Properties → gear_parameter → double_helix), the helix angle β (Properties → Data → gear_parameter → beta) for the helical gearing must first be entered.
  • If there are several gears, pay attention to which gear is set to reversed_backslash.
  • Only change the pressure angle if sufficient knowledge of the gear geometry is available.
  • Using ISO (International Organization for Standardization) guidelines, Module size is designated as the unit representing gear tooth-sizes. However, other methods are used too (Module (m): m = 1 (p = 3.1416), m = 2 (p = 6.2832), m = 4 (p = 12.566). If you multiply Module by Pi, you can obtain Pitch (p). Pitch is the distance between corresponding points on adjacent teeth.
  • If the number of teeth is changed, the pitch diameter also changes (dw).
  • Undercut occurs when the number of teeth of a gear is too small. An undercut leads to a weakening of the strength of the tooth!

Limitations

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