Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:
Clarity and completeness are both essential in production drawings. When a gear uses a standardized tooth system, the drawing customarily represents the gear as a blank with dimensional datums and adds notes specifying all tooth data, tolerances, and the applicable standard, instead of drafting each tooth profile.
Given Data / Assumptions:
Concept / Approach:
The drawing should enable unambiguous manufacture and verification. Showing the blank (ODs, faces, hubs, keyways) plus full gear data (module/DP, pressure angle, helix if any, accuracy grade, backlash, heat treatment) meets that goal with superior readability compared to explicit tooth drawings.
Step-by-Step Solution:
1) Define blank geometry and datums.2) Add tooth system parameters and tolerances in notes.3) Reference the governing standard to lock definitions.4) Include inspection and heat treatment requirements as applicable.
Verification / Alternative check:
Shops routinely request numeric specifications and standards references. Inspection reports cite the same standards, validating that tooth depiction is unnecessary on the drawing face.
Why Other Options Are Wrong:
Incorrect contradicts common drafting practice. Size or rendering based exceptions are not general rules. Partially correct understates how widely this convention is used.
Common Pitfalls:
Forgetting to specify accuracy grade or backlash; omitting datum references leading to ambiguous inspections.
Final Answer:
Correct
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