2D-Cam: Elements and Dialog-Boxes

2D-Cams have a number of 'related' elements and FBs. Their relationships are indicated in the table below.

You must link the 2D-Cam to the Cam-Data FB to obtain a 2D-Cam's kinematic-data [cam-coordinates, pressure angle, radius of curvature.

To find a 2D-Cam's force, stress and cam-torque data, you must also Configure the Power Source', enter its material properties, and edit the mass properties of each Part in the model.

Release 12:

ADD ELEMENTS

 

DIALOG-BOXES

STEP 1: Add 2D-Cam

Select

Part: as the Cam-Part
Profile: as the Cam-Follower

--> EDIT to OPEN -->

[optionally]

Cam Display and Properties dialog-box

Display Cam1, Pitch-Circle, Cam2
Display Cam as Profile, Contact-Force
Display Colour

*Material-Properties for Cam-Analysis

STEP 2 : Add Cam-Data FB

 

--> EDIT to OPEN -->

[necessary]

STEP 3 : Cam-Data FB dialog-box

Select the 2D-Cam [STEP 1]

STEP 4A : Cam-Analysis [with Graph FB]

Output-Connectors of Cam-Data FB:

Contact-Force*
Contact-Shear-Stress*
Radius-of-Curvature
Pressure-Angle

 

STEP 4B : Cam-Coordinates dialog-box

Cam-Coordinates

as Points or Arcs
save as DXF, TXT, STEP
transfer to SOLIDWORKS

STEP 5 *Force analysis only: Configure Power Source, Mass Properties of Parts

Release 13: [Difference: Select 2D-Cam in the Cam-Coordinates dialog-box]

ADD ELEMENTS

 

OPEN DIALOG-BOXES

STEP 1A

Add 2D-Cam

Select a:

Part: the Cam-Part
Profile: the Cam-Follower

... optional ...

 

STEP 1B

Open: Cam Display and Properties dialog-box

Display Cam1, Pitch-Circle, Cam2
Display Cam as Profile, Contact-Force*, ...
Display Colour

Note: Make sure *material-properties are correct

STEP 2A

Add Cam-Data FB

 

... necessary ...

 

 

STEP 2B

Open: Cam-Coordinates dialog-box

Select the 2D-Cam

Close dialog to do STEP 3A

STEP 3A

Cam-Analysis [with Graph FB]

Output-Connectors of Cam-Data FB:

Contact-Force*
Contact-Shear-Stress*
Radius-of-Curvature
Pressure-Angle

... after Cam-Analysis ...

STEP 3B

Open Cam-Coordinates dialog-box again

Calculate Cam-Coordinates as Points or Arcs

Save as DXF, TXT, STEP
Transfer cams directly to SOLIDWORKS

*Force analysis only: Configure Power Source, Mass Properties of Parts

How to open the 2D-Cam Display and Properties dialog-box

tog_minus        Use the Graphic-Area

2D-Cam in the Graphic-Area

Double-Click

Double-Click

1.Double-click a 2D-Cam profile in the graphic-area.

 

Right-Click

Right-Click

Right-Click

1.Right-click a 2D-Cam profile in the graphic-area.
2.Click Edit element in the contextual menu

tog_minus        Use the Assembly-Tree

2D-Cam in the Assembly-Tree

2D-Cam in the Assembly-Tree

A 2D-Cam is a child to a Cam-Plate which is also a child to a Part.

1.Find the 2D-Cam element in the Assembly-Tree1s-red
2.Right-click 2D-Cam element in the Assembly-Tree
3.Click 'Edit Element' in the contextual menu2s

tog_minus        Use the Selection-Window

2D-Cam and Polyline in the Selection-Window.

2D-Cam in the Selection-Window.

Use the Selection-Window

1.Click the 2D-Cam in the graphic-area, or Assembly-Tree

The 2D-Cam shows in the Selection-Window

2.Right-click the 2D-Cam element in the Selection-Window
3.Click 'Edit' in the contextual menu.

Cam Display and Properties dialog-box

2D-Cam Display and Properties dialog-box

2D-Cam Display and Properties dialog-box

Dialog-R12-2DCamProps-CamVisibilities

Display the Cam as

Cam 1
Pitch-Curve. [a dashed line]

and , or

Cam 2

Notes:

You can display all three.
You must display a minimum of one.
Look in the graphic-area to see which is which cam.

Dialog-R12-2DCamProps-CamDisplayOptions

Radio buttons to display the cam as a:

Cam-Profile only [default]
*Maximum Contact Shear-Stress
*Contact Force
Pressure Angle

See also: Cam-Data FB

See also: Cam Analysis and Checklist


* The Power Source must be configured correctly.

1.Configure the Power Source:  to make the 2D-Cam as the Power Source for the kinematic-chain in which the Cam-Follower is a Part.

It is not necessary to Display Forces.


Line Thickness of Cam: [default =1]

Increase the thickness of the cam profile.

Increase the Line Thickness for Cam Display that is not 'Cam Profile'.


Show Instant Centres : for the kinemagicians

Example Cam Display Option:

Cams in Graphic Area as 'Cams Only'

 

Cam Profile

 

1s-red Cam 1 and 2 are continuous lines.

2s Pitch-Curve is a dashed line.

Cams in Graphic Area as 'Maximum Contact Shear Stress'

Maximum Shear-Stress

Each point around the cam has a unique Maximum Shear-Stress.

See image:

1s-red The value of the Maximum Shear Stress at the contact point

2s The colour of the cam profile agrees with the colour-bar3s.

3s The colour-bar is a scale of the Maximum Shear-Stress.

Cams in Graphic Area as 'Cams Contact Force'

Contact Force

Refer to the image:

1s-red The value of the Contact Force is at the contact point.

2s  The colour of the cam profile agrees with the colour-bar3s

3s The colour-bar is a scale of the Contact Force

Cams in Graphic Area as 'Cams Pressure Angle

Pressure Angle

1s-red The value of the Pressure Angle is adjacent to the contact point between the Cam-Follower and Cam

2s The colour of the Cam agrees with the colour-bar3s

3s A colour-bar is a scale of the Pressure Angle

See Also Pressure Angle

Dialog-R10-2DCamDisplay-HertzianStress

Material Properties

To calculate the Maximum Contact Shear-Stress enter, enter for the Cam and Cam-Follower, the:

Poisson's Ratio
Elastic Modulus You must enter all of the zeroes!

[Elastic Modulus is also called Young's Modulus].


Notes:

See also: Cam Analysis and Checklist

See also: www.matweb.com for material properties.

Dialog-R10-2DCam-PropDisplay-RadiusOpen

Check-box: Open Cam / Closed Cam

'Rise Only' (Open Cam)

- or -

'Rise - Return' (Closed Cam)

See more details below


Cam-Radius  ∕  Cam-Follower Radius [%]

When the radius of the cam [Rc] becomes less than 100% of the radius of the cam-follower [Rf] there is a risk of undercutting.

See Also Cam Analysis Check-List, Application Options


Cam Range Start [R13+] & Cam Range:

Calculate the cam over a reduced range. usually less than 360.

For example:

If the cam rotates two times in one machine cycle, then enter Cam Range Start: 0 ; Cam Range : 180
If the cam is a 'slot-cam', the cam-follower moves along the cam in two directions. Then, enter a value in the Cam-Range box to calculate the cam only as the cam-follower moves in one direction.

This is not always possible, as the cam-follower may have a complex motion in the right and left directions, even at points that are not at the two ends of the cam.


CamRange-OpenCam

Examples of Open / Closed Cam and Cam Range

For example: a reciprocating 'Slot-Cam' that moves to the right and left. [see image]

Cam-Range Start: 0 ; Cam Range: 120

The first points of the Cam are at the start [left-side] of the profile.
The cam-follower starts to move from the right-side towards the left again at 120 MMA

CamRange-ClosedCam

Rise Only: clear check-box;

The cam does not have a 'fly-back' line.

Rise-Return: select check box;

The cam does have a 'fly-back' line.

Help Files for MechDesigner and MotionDesigner 11.1 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd