All-Terrain Wheelchair System

Transcription

1 All-Terrain Wheelchair System Drawing Package Ohio University Russ College of Engineering and Technology Mechanical Engineering Department June 6th, 2011 Design Team: Brad Geddes Todd Linthicum Matt McAllister Anthony Palermo Slade Simpson

2 Table of Contents Figure 1: Fully Assembled Rear Suspension System (Isometric View) 3 Figure 2: Fully Assembled Rear Suspension System (Principal Views) 4 Figure 3: Rear Suspension Sub-Assemblies and Parts...5 Table 1: Rear Suspension Parts List...5 Figure 4: Front Arm Extension (Isometric View)..6 Figure 5: Front Arm Extension (Principal Views).7 Bill of Materials... 8 Figure 6: Rotating Link Sub-Assembly and Parts..9 Table 2: Rotating Link Sub-Assembly Parts List...9 Figure 7: Frame Clamp Sub-Assembly and Parts.10 Table 3: Frame Clamp Sub-Assembly Parts List..10 Figure 8: Support Clamp Sub-Assembly and Parts..11 Table 4: Support Clamp Sub-Assembly Parts List...11 Geometric Tolerance Summaries Part Drawings Rear Suspension Assembly (RS) Front Arm (FA) Rotating Link Sub-Assembly (RL) Frame Clamp Sub-Assembly (FC) Support Clamp Sub-Assembly (SC)

3 Figure 1 : Fully Assembled, Right Side, Rear Suspension System (Isometric View) -3-

4 Top View: Front View: Side View: Figure 2: Fully Assembled Rear Suspension System (Principal Views) -4-

5 Frame Clamp (FC-01) Camber Tube Rigid Link Support Tube Shock Screw 2x Support Clamp (SC-01) Rotating Link (RL-01) Rotating Screw 2x Figure 3: Rear Suspension Sub-Assemblies and Parts Table 1: Rear Suspension Parts List Part/Sub-Asm Description Drawing Numbers Quantity Rigid Link RS-01 2 Camber Tube RS-02 1 Support Tube RS-03 1 Shock Screw Item Rotating Screw Item

6 Figure 4: Front Arm Extension (Isometric View) -6-

7 Side View: Bottom View: Back View: Figure 5: Front Arm Extension (Principal Views) -7-

8 Bill of Materials Item Description Sub- Assembly Part Name Drawing Number Quantity Vendor Unit Cost 1 Fox Air-Shock RL Air Shock - 2 Athens Bike Shop $ x4x Al FA Front Arm FA-01 1 McMaster-Carr $ x2x Al RL Rotating Link RL-02 1 McMaster-Carr $ x4x AL FC Upper/Lower Frame Clamp FC-02 FC03 1 McMaster-Carr $ ¾ Shoulder Bolt RS Rotating Screw - 2 McMaster-Carr $ ½ Shoulder Bolt RS Shock Screw - 2 McMaster-Carr $ Bronze Flanged Bushing RL Bronze Bushing - 2 McMaster-Carr $ Quick Disconnect Axle Sleeves OD Nylon Rod RL RL Axle Sleeves - 2 Ti-Lite $10.00 Upper/Lower Shock Spacer RL-03 RL04 1 McMaster-Carr $ Flat Black Spray Paint RS Rigid Link RS-01 2 Walmart $ / AL Rod FC Locating Pin FC-04 1 McMaster-Carr $ ½ x36 Solid Round Bar 304 Stainless RL Shock Pin - 1 (Scrap) if Bought McMaster-Carr $ ¼ -20x1 Pan Head Cap Screw ¼ -20x2.25 Cap Screw FC Clamp Screws - 16 McMaster-Carr $0.15 SC Support Clamp Bolt - 4 McMaster-Carr $ x6 x ¼ thick plate of 304 Stainless RS Rigid Link RS-01 2 (Donated for prototype) if bought from McMaster-Carr $ OD 6061 AL tube stock 36 RS Camber Tube RS-02 1 McMaster-Carr $ x round bar RS Support Tube RS-03 1 McMaster-Carr $

9 Rotating Link Sub-Assembly Upper Shock Spacers (RL-04) Air Shock Lower Shock Spacers (RL-03) Rotating Link (RL-02) Shock Pin Axle Sleeve Bronze Bushings Figure 6: Rotating Link Sub-Assembly and Parts Table 2: Rotating Link Sub-Assembly Parts List Part Description Drawing Numbers Quantity Rotating Link RL-02 2 Lower Shock Spacer RL-03 4 Upper Shock Spacer RL-04 4 Shock Pin Item Bronze Bushings Item 7 2 Air Shock Item 1 2 Axel Sleeve Item

10 Frame Clamp Sub-Assembly Frame Clamp Top (FC-02) Frame Clamp Bottom (FC-03) Locating Pin (FC-04) Clamp Screws Figure 7: Frame Clamp Sub-Assembly and Parts Part Description Drawing Numbers Quantity Frame Clamp Top FC-02 2 Frame Clamp Bottom FC-03 2 Locating Pins FC-04 4 Clamp Screws Item

11 Support Clamp Sub-Assembly Support Clamp Half (SC-02) Support Clamp Bolt Figure 8: Support Clamp Sub-Assembly and Parts Part Description Drawing Numbers Quantity Support Clamp Half SC-02 4 Support Clamp Bolts Item

12 Geometric Tolerance Summary Front Arm Rigid Link Author: Todd Linthicum Drawing Number(s): FA-01 Page(s): The front extension arms are made of T aluminum bar stock with dimensions of 2X4.The arms require tight tolerances in only three locations. The first location is the bearing seats which are required to be / Second, the mounting section which sits in the existing bearing seats on the chair, these concentric cylinders must all be +/ Finally, the last important tolerance is the lateral stabilization cut-out which must have a slight interference fit with the existing wheelchair frame. Its dimensions are / Author: Slade Simpson Drawing Number(s): RS-01 Page(s): Both rigid links were fabricated from one square (12x12 ) of ¼ 304 Stainless Steel. The general shape of the link itself does not require any high tolerances, but specific regions of each plate do. First, the holes for the locating pins require tolerances of +/ Although this is an extremely high tolerance, is was necessary, due to the fact that the stability of the whole rear systems rest on these two locating pins. The holes for the flat head bolts (those attaching the frame clamp to the rigid link) themselves did not have high tolerances, however, the locations of the holes relative to each other was very important. The other region of high tolerance is where the shoulder screws attach through the housing and the link itself. This was difficult to maintain due to the welding required, but was reamed post-weld to ensure a uniaxial relationship. The tolerance for this relationship was approximately +/

13 Camber/Support Tube Author: Matthew McAllister Drawing Number(s): RS-02, RS-03 Page(s): The Camber Tube s tolerance across the whole of the part is not as important as the ends where there is a locational fit between the tube and the frame clamp. This allows the clamp and tube to act rigid. The support tube has to be drilled and tapped on each end to allow the tube to affix itself to the system. Rotating Link Author: Slade Simpson Drawing Number(s): RL-02 Page(s): Each rotating link was machined from a 2x2x12 piece of 6061-T6 Aluminum. Like the rigid link, the shape of the rotating link itself did not require a general tolerance, but specific sections of the piece did. First, the hole for the axle sleeve required tolerances of +/-.005 to ensure the threading tool would properly cut the hole. Secondly, the pivot hole needed a high tolerance of +/-.001, due to the bushings needing to be securely pressed into them. Finally, the shock attachment hole required moderate tolerances of +/-.01 due to the fact that we turned down the pin form the shock ourselves, making any size (as long as it was <.5 in diameter) acceptable. Frame Clamp Top and Bottom Location Pins Author: Anthony Palermo Drawing Number(s): FC-02, FC-03 Page(s): Author: Matthew McAllister Drawing Number(s): FC-04 Page(s): 31 These pins assure the correct placement of the frame clamp to the rigid link. Due to the critical aspect of the location, these pins must be turned down to the proper size, machining from the stock size will be required. -13-

14 -14-

15 -15-

16 -16-

17 -17-

18 -18-

19 -19-

20 -20-

21 -21-

22 -22-

23 -23-

24 -24-

25 -25-

26 -26-

27 -27-

28 -28-

29 -29-

30 -30-

31 -31-

32 -32-

33 -33-