5. Mechanism Assembly
In this exercise we will see an example of the Mechanism Assembly, by creating a Slider mechanism assembly.
Stage 1: Early preparations Stage 2: Create the Stage 3: Define the
assembly Mechanism assembly
Define the main part
Stage 4: Define the Stage 5: Define the Stage 6: Define the
Mechanism assembly Mechanism assembly Mechanism assembly
Define the Parent / Child Define Interchangeable Catalog relations
relationships parts
Stage 7: Define the Stage 8: Save the Stage 9:Load the
Mechanism assembly Mechanism assembly Mechanism assembly:
Apply Formulas
CimatronE 8.5 Mechanism Assembky 1
6. Stage1 Early Preparation
In this stage early preparations are done (in general, it is an optional stage depending upon the mechanism
assembly you are creating).
In this example, it is necessary to add some features to the slide core Slide Z 180, such as angle and plane, for
placing the leader pins later on and to allow the user easy and full control over these parameters. We will define
new dimensions to be saved later in the catalog
2 Mechanism Assembky CimatronE 8.5
7. Note that the Slide core in the Hasco catalog already contains these changes.
Define the Angle pin position
Copy the catalog part Training Slide Z 180.elt into your “standard parts” catalog
(C:CimatronCimatronECatalogsStandard Parts).
Select Tools/Edit Catalog Master – select the part.
The dimensions we are now going to add will be saved later in the catalog as:
'Pin angle': a (18 º) and 'Pin offset': dX (24)
CimatronE 8.5 Mechanism Assembky 3
8. Show the hidden Main Planes and create a Sketch on the YZ plane. Sketch a line with 18 º declined to the
vertical face and 24mm distance from the UCS in the Z direction.
Defining the position for the “2 pins Slider”
Define the position of the two other pins by a Symmetry- Sy parameter (17)
4 Mechanism Assembky CimatronE 8.5
9. Create the plane (“Defined by”) from the line in the X direction.
Create a sketch on the previously created plane. Using the symmetry line, sketch two lines at a distance of
17.
CimatronE 8.5 Mechanism Assembky 5
10. Control the height of the angle pin and the locking heel
Pin offset dZ (20)
6 Mechanism Assembky CimatronE 8.5
11. Create a parallel plane to the top face of the slide core.
Control the height of the locking heel.
Clearance C (0)
CimatronE 8.5 Mechanism Assembky 7
12. Create “plane parallel” (delta=0) from top face of the slide core
Save the catalog part
Select Save, the Save Catalog Part dialog is opened.
Select the Advanced option to display the full table.
8 Mechanism Assembky CimatronE 8.5
13. Add the new dimensions:
1. Pin angle a
2. Pin offset dX
CimatronE 8.5 Mechanism Assembky 9
15. 5. Clearance C
To add a new record to the table, select the relevant dimension from the graphic area.
These parameters should be saved as “Free dimensions”.
Press the Next button.
CimatronE 8.5 Mechanism Assembky 11
16. Adjust the dimensions in the table lines according to the general dimensions of the part.
Select Next and then Finish.
Stage2 Create the Assembly
Create the Assembly
In this stage we will create the assembly; add relevant parts, set connections and defined relations.
Parametric relations can be defined only within non catalog parts. If the assembly contains relations between
catalog parts it cannot be saved as an assembly catalog mechanism. This limitation is to avoid cyclic
dependencies in the assembly and regenerations problems.
Parametric relations are allowed between standard parts, or between a standard part and a catalog part (the
parametric relation must be added to the standard part).
12 Mechanism Assembky CimatronE 8.5
17. Unpack the file Slider Mechanism Z 180.ctf
Open the example assembly Slider Mechanism Z 180;
The example assembly contains the needed catalog parts.
Note that the Assembly mechanism should not contain sub-assemblies.
Interchangeable parts
Notice the interchangeable parts such as the Guide strip Z 185 and the Guide strip Z 185W.
Hide the Guide strip Z 185. Note that the Guide strip Z 185W is in the same location.
CimatronE 8.5 Mechanism Assembky 13
18. In this example, both Guide strip Z 185 and the Guide strip Z 185W were added to the assembly.
We will define these parts as interchangeable parts; meaning that these are parts that can be interchanged with
one another when loading the assembly from the catalog.
The assembly should contain all optional (interchangeable) parts that you intend to have. Off course when
adding the mechanism assembly from the catalog, only the relevant part of the interchangeable will be opened
and the other will be in suppress mode.
Connections between the parts
Note the connections between the parts in the assembly.
Edit the connection Concentric69 of the purple guide pillar.
The purple guide pillar is Concentric to the line defined in the slide core.
Edit the connection Coincident70.
14 Mechanism Assembky CimatronE 8.5
19. The center of the top face is coincident to the plane (Pin offset dZ).
Add a “non-catalog” part to the assembly
Add a new part lower wear plate. Place the part on the assembly UCS.
In the new part, create main planes.
Create a rectangular sketch on the XZ plane. Take a reference from the width of the slide core Z 180. The
length is 100mm.
CimatronE 8.5 Mechanism Assembky 15
20. Extrude the sketch to delta 5 mm.
Note that Parametric Relations can be defined only within non-catalog parts. The catalog part can be the
server while the non-catalog part is the client.
Create Parametric Relation
Create a parametric relation between the lengths of the new wear plate and the length of the Slide core
Z180.
L wear plate = 1.5xL slide.
16 Mechanism Assembky CimatronE 8.5
21. Save the assembly.
Define the Mechanism assembly
Stage 3 Define the main part
Define the main part
Define the Mechanism assembly; this is done in a few stages:
Define a Main Part, define the Parent / Child relationships, define Interchangeable parts, Catalog relations and
Formulas.
Defining a Main Part to the Mechanism assembly is a mandatory stage; all the other stages are optional.
The Main Part will always be in the assembly and cannot be dependent in other parts. Only one part can be the
Main Part.
Activate the main assembly. From the main menu, select Catalog / Create Mechanism Assembly / Main
Part.
Select the slide core and press OK.
Mechanism Assembly operations can only be performed on an assembly once a Main Part has been defined.
CimatronE 8.5 Mechanism Assembky 17
22. Stage 4 Define the Parent/Child Relationships
Define Parent
This step, enables you to create groups of parts that will be suppressed/unsuppressed together. It also will
determine the "direction" of Catalog Relations (CR) between the parts.
For example, if there are screws and dowel pins that are children of the guide strip, this means that suppressing
the guide strip (the parent) will also suppress the screws and pins (the children). It also means that the
dimensions of the screws and pins will be controlled by the guide strip and not vice versa.
From the main menu, select Catalog / Create Mechanism Assembly / Parent/Child
Select the Guide strip Z185 in the left pane and press the New Parent button.
18 Mechanism Assembky CimatronE 8.5
23. A new parent is added to the right pane.
Note that:
Instances of the same part can be parents of different children.
Instances of the same part can be children of different parents.
Define Child
Select the parent, then the two instances of “Cap screw Z30” in the right pane.
Make sure you select the screws which belong to this Guide strip.
Press the Child button.
CimatronE 8.5 Mechanism Assembky 19
24. Complete the Child/Parent relationships so the dialog appears as follows:
Select OK.
Stage 5 Define Interchangeable parts
Stage 5 Define Interchangeable parts
Interchangeable Groups
This step enables you to define parts as Interchangeable Parts. These are parts that can be interchanged with
one another when loading the assembly from the catalog.
For example if a slider assembly has 2 types of Locking Heel, one of the 2 types can be selected when loading
the assembly from the catalog. The one that is not selected will be suppressed.
20 Mechanism Assembky CimatronE 8.5
25. Define Interchangeable parts
From the main menu, select Catalog / Create Mechanism Assembly / Interchangeable Parts.
Note that a Child part cannot be an interchangeable part (only a Parent and a free part).
Select the 1st Guide strip Z185W in the left pane of the dialog (or from the display).
Press the New Group button.
The selected part is moved to the Groups pane under a new group.
Type of right guide strip
Rename the group to Type of right guide strip.
Select the Type of right Guide Strip group in the right pane.
Select the equivalent Guide Strip Z185 part in the left pane.
CimatronE 8.5 Mechanism Assembky 21
26. (If selecting from the display area, use hide/show to make sure you select the right strip).
Press the Forward button.
The icons displayed in the Groups pane are:
Group
Parent part
Free part
The part is added to the group and becomes one of the interchangeable parts in that group.
22 Mechanism Assembky CimatronE 8.5
27. Complete the Interchangeable part definitions
Complete the Interchangeable part definitions so the dialog appears as follows:
Select the middle Guide Pillar as the single Drive Pin and the two outer Guide Pillars as the pair of Drive Pins.
Multiple parts can be defined simultaneously.
Select OK.
CimatronE 8.5 Mechanism Assembky 23
28. Stage 6 Catalog Filtering Relations
Catalog Filtering Relations
This step enables you to create Catalog Relations (CR) between components in the Mechanism Assembly.
These relations use the parent/child relationships and create filtering rules on the parts in the Mechanism
Assembly. These filtering rules enable the catalog to be filtered and only display a specific part size that meets
the defined relations.
This means that if, for example, the length of a screw is proportional to “rail height” when the assembly is
regenerated, the screw table display will be filtered to this specific screw length.
From the main menu, select Catalog / Create Mechanism Assembly / Catalog Filtering Relations
24 Mechanism Assembky CimatronE 8.5
29. 1st area displays the parts according to the following hierarchy of interchangeable type groups, then parents
and children below. Free parts and the Main Part are also in the first level.
2nd area displays the Component catalog records.
3rd area displays the relation expression you are currently creating.
4th area displays the list of already defined relations.
CimatronE 8.5 Mechanism Assembky 25
30. Crate a Catalog Relation
We will now create a “catalog relation” between the Guide strip height (the client) and the Slide Z180
height (the server).
Select one instance of the Guide strip Z185. Select the length h2 in the Component record field and hit
the button Attach dimension.
26 Mechanism Assembky CimatronE 8.5
31. The dimension appears in the Expression Editor left pane.
Note that:
• Only Primary Dimensions can be selected as “client dimensions”.
• Parts can be selected from the display area.
Expression
Set the “Equal” sign “=” from the list:
CimatronE 8.5 Mechanism Assembky 27
32. Select the Slide Z180 (as the server). Select the h1 dimension from Component record and attach it.
Add -1 to the expression. ( h1-1).
Press the confirm relation button to submit the new expression into the Relations list.
Note that when the assembly is loaded from the catalog, the table of the Guide strip will be filtered to
display the items with the proper height.
28 Mechanism Assembky CimatronE 8.5
33. Complete the creation of Catalog Relations
Complete the creation of Catalog Relations according to the following table.
Make sure you create the relation to the real parent. For example the cap screws should be related to their guide
strip, not the 2nd strip.
Guide strip Z185: h2 = Slide Z180: h1-1
Guide strip Z185: l1 > Slide Z180: l1
Cap Screw Z30: d = Guide strip Z185: d2
Cap Screw Z30: l = Guide strip Z185: h2
Guide strip Z185W: h2 = Slide Z180: h1-1
Guide strip Z185W: l1 > Slide Z180: l1
Cap Screw Z30#1: d = Guide strip Z185W: d2
Cap Screw Z30#1: l = Guide strip Z185W: h2
Locking heel Z182: b1 <= Slide Z180: b1
Wear plate Z1821: b1 = Locking heel Z182: b1
Wear plate Z1821: h2 = Locking heel Z182: h1
Countersunk socket head screw Z33: d = Locking heel Z182: d1
Countersunk socket head screw Z33: l = Locking heel Z182: t1+4
Press the appropriate arrow to move a relation up or down the list.
Select OK button to execute the process and exit from the dialog.
CimatronE 8.5 Mechanism Assembky 29
34. Stage 7 Formulas
Formulas
This step enables you to define formulas based on the dimensions of the parts in the assembly. These formulas
supply the necessary information when loading the Mechanism Assembly from the catalog and enable you to
choose the best combination of parts.
This means, for example, when loading the Slider mechanism from the catalog, you are able to verify that the
stroke of the slider is long enough to release the "undercut". The formula will determine the stroke from the
length and angles of the pins.
From the main menu, select Catalog / Create Mechanism Assembly / Formulas.
Free Variables
The upper section of the dialog is used to define Free Variables. These variables do not exist in the model and
you can define them and use them in the formulas. If no free variables were defined, the formula will only include
dimensions from the model.
30 Mechanism Assembky CimatronE 8.5
35. Formulas
The lower section of the dialog is used to define Formulas.
New Variable
Press the New Variable button.
A new variable with a temporary default name is added to the Free Variable section.
Rename the new variable. Enter a description and a default value.
CimatronE 8.5 Mechanism Assembky 31
36. New Formula
Any mathematical signs and Free Variables can be added to the formula.
Press the New Formula button.
A new formula with a temporary default name is added to the Formulas section.
Rename the new formula Slider Width (the formula is the calculation of the entire Slider width).
Add dimensions to the formula adding the free variable name, i.e. W.
Multiply the Guide Strips Width (W) by 2 and type "+".
From the display area pick the width of a slide part to add it to the formula.
32 Mechanism Assembky CimatronE 8.5
37. Every picked dimension from the display area is added to the formula.
Click OK.
CimatronE 8.5 Mechanism Assembky 33
38. Stage 8 Save the Mechanism assembly
Save the Mechanism assembly
Save an assembly as a Mechanism Assembly. This creates a Mechanism Assembly from an assembly of
catalog parts.
Note: The Save as Mechanism Assembly option is only available once a Main Part has been defined for
the Mechanism Assembly.
Select File/ Save as Mechanism Assembly and add the following pictures Hasco Slider 1.jpg and Hasco
Slider 2.jpg picture.
Select OK.
34 Mechanism Assembky CimatronE 8.5
40. Stage 9 Load the Mechanism assembly
Load the Mechanism assembly
Open a new assembly. Save the Assembly.
Select the Add from catalog icon.
Select the saved Mechanism Assembly from the Catalog.
Save the assembly.
Select Place by UCS and select the Assembly UCS.
The Mechanism Assembly is now displayed in preview mode. The first option in every group of interchangeable
parts is initially displayed.
36 Mechanism Assembky CimatronE 8.5
41. Edit Parameters
Select Edit Parameters
The Mechanism Assembly Adjustment dialog is displayed.
Notice the following buttons:
Select this button to change groups
Suppress
Unsuppress
Filtered tables
CimatronE 8.5 Mechanism Assembky 37
43. Change interchangeable group
Change the interchangeable group; select No. of Drive Pins (2).
CimatronE 8.5 Mechanism Assembky 39
44. Press the Expand Advanced button.
Change some of the free parameters to see the effect in the preview.
Press the Apply button to view the result.
Change the angle back to 18.
Catalog table
Change values of parent parts and see how the system displays the filtered table with the relevant parameters
only.
If Catalog Filtering Relations have been define for this part, the catalog table will be filtered and only the
appropriate parts are displayed in the table. If necessary, you can cancel the filter and the whole catalog table
(for the part) is displayed.
40 Mechanism Assembky CimatronE 8.5
45. Open the table of the left guide strip. Notice the relevant rows in the table.
Change the size of the slide core from Z180-20*63*63 to Z180-32*100*80.
CimatronE 8.5 Mechanism Assembky 41
46. Reopen the table of the left guide strip. Notice that the relevant rows have been changed according to the
new slide core size.
42 Mechanism Assembky CimatronE 8.5
