Dialog: Cam Coordinates

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Dialog: Cam Coordinates

Cam-Data FB > Cam-Coordinates

See Add Cam-Data FB  


We use the Cam-Data dialog-box to:

Calculate Cam-Coordinates

Export the Cam-Coordinates

Save the Cam-Coordinates as a TXT, DXF, or as a STEP file.


2D-Cam - work-flow

1.Add a 2D-Cam - see Add 2D-Cam


If the new 2D-Cam is a Conjugate-Cam or a Groove-Cam (that is, a Body-Closed Cam):

1.a. Add a Conjugate-Cam FB - see Add Conjugate Cam FB

1.b. Edit the Conjugate-Cam FB - add 2×flanks from 2×2D-Cams - see Conjugate-Cam dialog-box.


2.Select the 2D-Cam or the Conjugate-Cam as the Power Source for the Follower - see Configure-Power Source

3.Edit the 2D-Cam to edit which cam-profile to display: Display, Properties, Life, ... - see below

4.Add a Cam-Data FB - see Add Cam-Data FB

5.Edit the Cam-Data FB to link it to the 2D-Cam- - see Link the Cam-Data FB to a 2D-Cam

6.Connect wires from the Cam-Data FB to a Graph FB to analyse 5 parameters see Cam Analysis

7. Edit the Cam-Data FB again to Calculate the Cam-Coordinates - see below YOU ARE HERE:

Cam-Data dialog-box: Cam-Coordinates

MD-DIALOG-2DCAM-SELECT-2DCAM-1

If necessary, link the Cam-Data FB with a 2D-Cam - see Add Cam-Data FB


1s - Cam-Coordinates toolbar

2s - End-Caps - this box shows ONLY when the first coordinate of the Cam does not equal the last coordinate. E.g.: a linear Slot-Cam type.

3s - Inner / Outer - to indicate the status of the Cam-Coordinate calculations and Cams.

4s - Cam Options - Choose to calculate, display, and/or save the cam-profile coordinates for the Inner, Outer, Groove, or Negative Groove cam-type. The Negative Groove cam-type applies to the STEP file-type only.

5s - Radial Clearance - +ve Clearance (e.g. for Groove Cams)  or –ve as Interference (e.g. Coordinates for Rough Machining)

6s - # Points to calculate the XY-Points ( see toolbar 1s below )

or

6s - BiArc Error to calculate the BiArcs ( see toolbar 1s below )


1s tog_minus Cam-Coordinates toolbar:

2s - End Caps

End Caps relate only to Slot-Cams, also known as Linear-Cams, or Ramp-Cams.

End-Caps - Show

End-Caps - Show

Show or Hide End-Caps

End-Caps work well when the independent axis to the Cam-Follower moves in one direction only - see image: End-Caps - Show

If the independent axis reverses its direction in the middle of its travel, you will see False End-Caps in the middle of the Slot-Cam. - see image: Slot-Cam with 'False' End-Caps.


Before you export Cam-Coordinates we recommend you add a new dummy slot-cam - but, over one machine-cycle, and move the main axis of the Slot-Cam in one direction at Constant-Velocity.

To make sure the Constant-Velocity is correct:

1.Connect a wire from a Linear-Motion-FB to a Gearing FB

2.In the Gearing FB, enter a Gearing Ratio = (maximum Travel distance of Cam) / 360).

3.Connect a wire from the Gearing FB to the Motion-Dimension FB as the motion of the Slot-Cam.

As the MMA increases from 0 to 360, the Cam will travel from 0 to Maximum Travel distance of Cam (mm) See Tutorials on-line.

Slot-Cam with 'False' End-Cams

Slot-Cam with 'False' End-Cams

End-Caps - Hide

End-Caps - Hide

3s - Cam Status

MD-Dialog-2DCamCoordiantes-Schematic-B

The cam-coordinates have been calculated.

The Radius-of-Curvature is more than the Cam ROC Soft-Limit parameter as set in the 2D-Cam dialog-box

MD-Dialog-2DCamCoordiantes-Schematic-Outer-Inner-NOT

The cam-coordinates have not been calculated - usually after you have edited the # Points or the BiArc Error.

MD-DIALOG-CAMCOORDIANTES-CAM-STATUS

It is not possible to calculate the cam-coordinates, possibly because of under-cutting.

MD-DIALOG-CAMCOORDIANTES-CAM-STATUS-ROC

The cam-coordinates have been calculated.

The Cam's Radius-of-Curvature is less than (Minimum Radius Warning % × Roller Radius) as set in the 2D-Cam dialog-box - Undercutting is possible.

4s - Cam Options

Calculate, Display, and/or Save the Cam-Coordinates:

MD-STEP-INNER

Inner Cam-Profile ONLY

MD-STEP-OUTER

Outer Cam-Profile ONLY

MD-STEP-GROOVE

Groove-Cam

If you select Groove-Cam option, AND if you toggle 1s Red-14-5 to XY-Points, then you can also toggle 1s Red-14-4 to calculate the Pitch-Circle coordinates.

MD-STEP-NEGATIVEGROOVE

Negative-Groove

The Negative-Groove option applies only when you want to save the Cam as a STEP file-type - see 1s Red-14-2.

The STEP file is the space filled by the path of the Cam-Follower along the cam-profile (plus or minus any Radial Clearance).

5s - Radial-Clearance

Example Radial-Clearance

Example Radial-Clearance

Cam with 0.2mm Radial Clearance

Cam with 0.2mm Radial Clearance

See also : 2D-Cam dialog-box > Parameters tab > Cam Range and Radius


Radial Clearance (mm) Default = 0 , Negative or Positive

Positive Value - the cam is resized to give a clearance between the Cam-Follower and the Cam-Profile.

AND:

Negative Value - the cam is resized to give an interference between the Cam-Follower and Cam-Profile.

Applications:

E.G.1: Groove-Cam - to add a small clearance (Positive Value) for a Cam-Follower bearing in a Groove cam-type (See Note )

E.G. 2: Conjugate-Cam - to add a small clearance (Positive Value) to compensate for tolerances in the cam assembly.

E.G. 3: Rough-Cut - to oversize the cam for a Rough-cut. Radial-Clearance should be a Negative-Value

Note:  Stud-type Cam-Followers often have a large negative tolerance bias - e.g. . You may consider that to be enough clearance.

6s - Cam-Coordinates

Max Chord-Error with BiArcs

Max Chord-Error with BiArcs

1s Red-14-5 set to BiArcs

Apply this maximum Chord-Error between the true Cam-Profile and the BiArcs.

Number of XY Points

Number of XY Points

1s Red-14-5 set to XY-Points

Calculate these number of Points on the true Cam-Profile at equal increments of the Master-Machine Angle.


   Options for: Save as .STEP file-type

MD-DIALOG-CAMCOORDINATES-STEPFILEOPTIONS

8s - STEP-Only - To indicate the Front Face or the Back Face from which to extrude the Groove-Cam by Cam-Depth (see also 9s )

9s - STEP-ONLY -  Dimensions that apply to the Cam-Plate when you save the cam as a STEP file-type (see 1s Red-14-2 )

10s - STEP-ONLY - Schematics to indicate the Cam type, and if the Plate-Radius and Bore-Radius are suitable (see also 7s )

11s - STEP-ONLY - (Stationary Cam only) - enter an X-Offset and Y-Offset to move the center of the Cam-Plate, as required.

11s - Read-Only - Min. Inner-Cam and Max. Outer-Cam. Dimensions to help you to specify the Plate-Radius and Bore-Radius (see also 9s )

9s Dimensions for STEP file ONLY

These images are of a Groove cam-type that are saved as the STEP file-type, and then opened in SolidWorks to show the features.

MD-DIALOG-CAMCOORDINATES-STEPFILEOPTIONS-StepDims

MD-Dialog-2DCam-CamCoordinates-CamDepth

Red-14-2 Plate-Depth

The total depth of the Cam-Plate.

MD-Dialog-2DCam-CamCoordinates-GrooveDepth

Red-14-1b Cam-Depth

The depth of the Cam cut into the Cam-Plate. The width of the Cam-Flanks.

Plate-Depth Cam-Depth 2 mm

MD-Dialog-2DCamCoordiantes-STEP-Cam-Radius

Red-14-3 Plate-Radius

The radius of the Cam-Plate, when you select an Outer-Cam or a Groove-Cam - see

MD-Dialog-2DCamCoordiantes-STEP-Bore-Radius

Red-14-4 Bore-Radius

The radius of the hole through the center of the Cam-Plate

10s Schematics of Cam type and are the Dimensions OK or Not-OK?

MD-DIALOG-CAMCOORDINATES-STEPFILEOPTIONS-StepDims

Status of Cam Type, Blank-Radius and Bore-Radius relative to Cam-Size

The Plate-Radius Red-14-3 parameter applies to Outer and Groove Cams only 4s

The Bore-Radius Red-14-4 parameter applies to all Cam types 4s

MD-Dialog-2DCamCoordiantes-Groove-BlankOK-BoreOK-

4s Groove-Cam

Red-14-3 Plate-Radius is OK - it is greater than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is OK - it is less than the Minimum Radius of the Inner-Cam 11s

MD-Dialog-2DCamCoordiantes-Groove-Blank2Sm-BoreOK-

4s Groove-Cam

Red-14-3 Plate-Radius is NOT OK - it is less than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is OK - it is less than the Minimum Radius of the Inner-Cam 11s

MD-Dialog-2DCamCoordiantes-Groove-BlankOK-Bore2Bg

4s Groove-Cam

Red-14-3 Plate-Radius is OK - it is greater than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is NOT OK - it is greater than the Minimum Radius of the Inner-Cam 11s

MD-Dialog-2DCamCoordiantes-Groove-Blan2Sm-Bore2Bg

4s Groove-Cam

Red-14-3 Plate-Radius is NOT OK - it is less than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is NOT OK - it is greater than the Minimum Radius of the Inner-Cam 11s

MD-Dialog-2DCamCoordiantes-Inner-Blank0-Bore0

4s Inner-Cam ONLY

Red-14-3 Plate-Radius is 0mm

Red-14-4 Bore-Radius is 0mm - the Cam will not include a Hole through its center

MD-Dialog-2DCamCoordiantes-Inner-BlankOK-BoreOK

4s Inner Cam ONLY

Red-14-3 Plate-Radius is OK - it is greater than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is OK - it is less than the Minimum Radius of the Inner-Cam 11s

MD-Dialog-2DCamCoordiantes-Groove-Blank2Sm-BoreOK-

4s Inner-Cam ONLY

Red-14-3 Plate-Radius is NOT OK - but, this dimension is ignored with Inner Cams 4s

Red-14-4 Bore-Radius is OK - it is less than the Minimum Radius of the Inner-Cam 11s

You can save the STEP file.

MD-Dialog-2DCamCoordiantes-Groove-BlankOK-Bore2Bg

4s Inner-Cam ONLY

Red-14-3 Plate-Radius is OK - it is greater than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is NOT OK - it is greater than the Minimum Radius of the Inner-Cam 11s

You can NOT save the STEP file.

MD-Dialog-2DCamCoordiantes-Outer-BlankOK-BoreOK

4s Outer-Cam ONLY

Red-14-3 Plate-Radius is OK - it is greater than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is OK - it is less than the Minimum Radius of the Inner-Cam 11s

MD-Dialog-2DCamCoordiantes-Groove-Blank2Sm-BoreOK-

4s Outer Cam ONLY

Red-14-3 Plate-Radius is NOT OK - it is less than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is OK - it is less than the Minimum Radius of the Inner-Cam 11s

You can NOT save the STEP file.

MD-Dialog-2DCamCoordiantes-Groove-BlankOK-Bore2Bg

4s Outer-Cam ONLY

Red-14-3 Plate-Radius is OK - it is greater than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is NOT OK - it is greater than the Minimum Radius of the Inner-Cam 11s

You can save the STEP file.

MD-Dialog-2DCamCoordiantes-Ng-Groove-OKOK

4s Negative Groove-Cam

Red-14-3 Plate-Radius is OK - it is greater than the Maximum Radius of the Outer-Cam 11s

Red-14-4 Bore-Radius is OK - it is less than the Minimum Radius of the Inner-Cam 11s


11s Minimum/Maximum Radius of Cams, Offset X and Offset Y.

Minimum of Inner-Cam and Maximum of Outer-Cam (see also 9s )

MD-CAMCOORDIANTES-MININNER-MAXOUTER

These value are useful to know when you want to make sure there is a minimum wall thickness between

the Bore diameter and  the Inner Cam-Profile and

the Plate diameter of the Outer Cam-Profile.


X-Offset and Y Offset

When the Cam is a Stationary Cam:

enter an X-Offset and Y-Offset to move the center of the Cam-Plate relative the 0,0 of the Mechanism-Plane / Base-Part.

MD-CAMCOORDIANTES-XYOFFSET

MD-Dialog-2DCamCoordiantes-STEP-No-Offset

Offset-X = 0, Offset-Y = 0

These are Read-Only if the Cam is a rotating part.

If the Cam is stationary then you can move the center-Point of the Blank-Radius and the Bore-Radius to the center of the Cam.


Image left: the Blank-Radius and Blank-Bore with Offset-X=0,-Y=0.

MD-Dialog-2DCamCoordiantes-STEP-Offset

Centre-X = 20, Center-Y = 30

Image left: the Blank-Radius and Blank-Bore with Offset-X=20,Y=30.


The maximum radius of the Blank-Bore can be increased, and the minimum radius of the Blank-Radius can be decreased.


Notes:

Note 1: When a 2D-Cam is a rotating-cam, make sure that the start-Point (origin) of the Part that is the Cam-Part is at the center of rotation.

Note 4: The data will be on the Front-View of the SOLIDWORKS document, with Z columns as 0. SOLIDWORKS fits a Spline to it immediately. If you need to put the data on a different plane in SOLIDWORKS, then you will need to change the data slightly in Excel. Add a column of zeros in the X, Y or Z column.

Possibly multiply the X-column by –1,  to mirror the data about the Y-axis. Then import the data as a Curve entity into SOLIDWORKS.


The Cam as BiArc Data has six columns:

1

2

3

4

5

6

Arc Radius

Arc Start Point X Coordinate

Arc End Point X Coordinate

Arc Start Point Y Coordinate

Arc End Point Y Coordinate

Arc Angle Range (degs)