Framus Unlimited Inc.

100 Institute Rd.
Worcester, Massachusetts
Memorandum

To: Young Swan's Design Groups
From: Chief Swan
Subject: Swansong: Don't Forget the Cannolis! (ME 3310 Project 3 Term A-92)
Date: Assigned 10/5/92 – Final report due on 10/16/92 @ 4 Pm

    The Godfather's Cannoli Company Inc. has made us an offer that we can't refuse: i.e., - design a cam-driven cannoli-making machine for their new 100/minute automated pastry-assembly line. These delicious sweet-treats are expected to wipe out competition from the Mom and Pop bakeries that are behind on their protection payments.

    The cannoli dough is a thin, 5.5-inch diameter pastry disk which is carried through an oven on a linkage-driven, intermittent-motion conveyor. They are spaced on approximately 7.5" centers in the direction of travel. The cannoli pastry disks exit the oven and transfer onto a mandrel at the rolling station where they are moved transversely to allow a cam-driven mechanism to roll them around a stainless steel mandrel into their traditional tubular shape while they are still warm. Next, they are transported via a second conveyor past the cooling station where they harden to a brittle state. They then proceed to the filling station where a cam-driven pump injects the secret-recipe ricotta-cheese filling into the tube. Finally, they are transferred to another conveyor which takes them to the packaging station.

There are three main sub-tasks within this project:

    1 Design a cam to insert and retract the mandrel.

    2 Design a cam to roll-up the cannoli dough into a cylindrical shape around the mandrel.

    3 Design a cam(s) to insert the nozzle into the cannoli and pump the filling into it.

    These tasks are interrelated and interdependent. The team should assign its resources as appropriate to cover all three tasks. We suggest that each task be assigned to one team member. There will be tradeoffs in respect to the time allotted for each event. Your team will have to work out those conflicts. Our Consigliere, Webfoot, has looked into some preliminary design concepts and suggests the general approach described in Figures 1 and 2. The conveyors will be driven by a "walking-beam", fourbar linkage with a 60/40 duty cycle, meaning that it is driving the conveyor for 60% of the cycle and resetting itself for the next stroke during 40% of the cycle. The oven conveyor surface is higher than the filling conveyor by about the diameter of a cannoli. The cannoli is driven off the end of the oven conveyor onto the waiting mandrel and placed centrally thereon. The mandrel then moves forward axially to the rolling station where the "holy roller" mechanism (see Figure 2) is driven by its cam so as to wrap the cannoli around the mandrel "upside down". The mandrel rotates 1808 about its axis to turn the shell right side up, then replaces the formed shell back on the filling conveyor. The mandrel is then retracted from the cannoli before the filling conveyor starts its next motion cycle. The filling conveyor then carries the cannoli shell to the filling station and stops it while the pump nozzle is inserted into the cannoli and injects the filling. The filling is a material with strange fluid properties. It has a great deal of entrained air in it which becomes pressurized during the pump stroke. The energy stored in this compressed air can cause the filling to continue to drool out of the shell after the pump has stopped. The pump-cam design needs to compensate for this in some way.

    As with any design problem, there is an infinity of solutions possible. You are expected to come up with the best solution you can design. To do so you will have to try out many alternate designs and iterate to your 'best' solution. You should expect to typically go through at least ten iterations before arriving at an acceptable one. Some measures of "better" designs will be: lower peak accelerations, smoother jerk, smaller physical cam size, good pressure angles and reasonable follower size. You may use either a flat faced or roller follower. You are required to compute the s, v, a, j functions, the pressure angles and radii of curvature of the entire cam and draw the cam profile. All of these tasks can be accomplished with program Dynacam.

    You are also required to document your solution in a professional engineering report which adheres to the Project Report Specifications document previously distributed. This report will document the process by which you iterated to your final design as well as the design itself. Do not just describe the final result. Rather show me how you arrived at it, including the failures encountered along the way. This will demonstrate to me that you understand the engineering concepts and the relevant course material. Note that unreferenced and undiscussed computer or other illustrations will be considered to be report "filler" and be ignored. Do not put anything in the report unless you discuss its meaning. NO model of your design is required. But, please do include a computer disk with your DYNACAM solution files on it.

    For this project, no specific background research is required beyond reading your textbook and asking questions of our resident cannoli expert, Chief Swan. See Chapters 9 and 17 and section 2-15. You may, if you wish, visit a local Italian bakery to see (and further sample) the finished product. (Note that this could be dangerous to your waistline) You may begin your report with the goal statement and task specifications followed by the design description phase of the design process. You may also include background research information if you wish, as an option. The report must include the following figures for each cam IN THE ORDER LISTED!

    -     A timing diagram for the whole cycle showing all events including the conveyor motion

    -     S-V-A-J diagrams in one plot for each subtask

    -     separate S, V, A, J plots (4 figures) for each subtask

    -     pressure angle plot for each subtask

    -     radius of curvature plot for each subtask

    -     the (3) boundary condition tables for each of your segments, for each subtask

    -     a cam profile for each subtask

    -     sketches of your cam-follower trains for each subtask

    -     any other data you think necessary

      IMPORTANT! IMPORTANT!

IT IS CRUCIAL THAT YOU START THIS PROJECT RIGHT AWAY! Do not kid yourself that you can knock this off over the weekend before it is due! You cannot! This type of problem requires incubation periods. Work on it until stumped, then put it aside and do other coursework. Then come back to this problem after your subconscious has had a chance to work on it. You'll be surprised how effective this 'time-sharing' of your tasks can be. Read The Design Process in Chapter 1 for more information on this phenomenon. Incubation really does work. You should plan to have all the design work done at least 2 days before the due date, and use that time to write it up. It will take about three times longer to write up the report than you think it will. Allow at least two days for the write-up.

    The report must be word processed and spell checked! WordPerfect (with built-in spell checker) is available in the Advanced Data Processing (ADP) Lab in Fuller Laboratories. If you have your own PC and word processor, that's fine too. Letter quality output is NOT required, but DARK type is. Use a good printer ribbon, or better yet, take your disk to CCC and laser print the final draft.

    This is a group project. Chief Swan will designate the groups. Each group is a team competing with every other group. Any duplication of results or designs across the various group's final reports will be quite obvious and will result in a very tense confrontation between those groups and me. The group will submit one project report which will indicate the contributions of each member on the title page.

    Now please re-read this document to ensure you understand what is being requested. If you are the least bit confused, ASK QUESTIONS IN CLASS OR SECTION MEETING. Above all, Have Fun!