Valve Cam Mechanism

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ME-430 INTRODUCTION TO COMPUTER AIDED DESIGN
Valve Cam Mechanism
Pro/ENGINEER Wildfire 3.0
Dr. Herli Surjanhata There are 6 parts that will be used in this mechanism analysis:
• shaft_mount.prt — the ground body.
• camshaft.prt (rotating body)
• rocker.prt (oscillating body)

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• valve_guide.prt (ground body)
• valve.prt (sliding body)
• rocker_shaft.prt (rotating body)

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PART: VALVE_GUIDE.PRT

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CREATE AN ASSEMBLY – rocker_arm.asm
Create a new assembly called
rocker_arm.
Uncheck Use default
template.
The New File Options dialog
box appears. Select
to assemble the
rocker_shaft.prt
at default
location. Click
to finish the assembly operation.

Click
and open rocker.prt,
Keep default setup for
assembly.
Apply the following constraints between rocker_shaft and rocker – see below.
• Align the axis of the rocker.prt with the axis of the of rocker_shaft.prt
Align constraint. • Align OFFSET the FRONT datum plane of the rocker.prt with the
ASM_FRONT datum plane of the rocker_arm.asm assembly Align
constraint. The offset distance is 25 mm.
12Select System of Units of
mmns_asm_design.

Under Parameters, fill
DESCRIPTION and
MODEL BY with Valve
Cam Mechanism and
your name.
OK.

The assembly should
have default datum
planes – ASM_FRONT,
ASM_RIGHT, and
ASM_TOP.
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Pick ASM_FRONT datum plane. 14Click OK and ADTM1 is created.

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Create a new datum plane through the axis of top hole of the shaft_mount. This
datum plane should be parallel with ASM_TOP.

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Create a datum plane through the axis of the top hole and make a 20° angle with
ADTM2 – see figure below.

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Create a datum plane through the axis of the top hole and normal with ADTM3 –
see figure below.

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Apply the following constraints in creating pin connection between rocker arm and
shaft mount– see figure below:
• Align the axis A_2 rocker_shaft of the rocker_arm.asm with the axis A_3
of the top hole of shaft_mount.prt as Axis alignment constraint. • Align the ASM_FRONT datum plane of the rocker_arm.asm with the
FRONT datum plane of the shaft_mount.prt as Translation constraint.
Pick and pick the rocker_shaft.

Drag-rotate the rocker shaft.

22Create a pin connection for the camshaft and shaft_mount.
Open camshaft.prt in the assembly.
From the list, select Pin for creating a
pin connection.
the intersection between ADTM1 and ADTM6.

Create a slider connection for the valve and valve_guide.
Open valve.prt in the assembly.