Page 279 - Design for Six Sigma a Roadmap for Product Development
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Axiomatic Design  249


           8.4.3 Transmission vane oil pump
           The transmission zigzagging exercise, in particular, FR 5.3   pump
           pressure control, is continued at the pump level in this example
           (Brejcha 1982).
             A hydraulic pump is a mechanism by which an external power source,
           namely, the engine, is used to apply force to a hydraulic media. Usually,
           the front pump drive is attached to the converter hub in automatic
           transmissions as depicted in Fig. 8.6. Figure 8.7 represents a side view,
           while Fig. 8.8 represents a top view of the vane pump (Brejcha 1982).
             A hydraulic pump provides work when it transmits force and motion
           in terms of flow and pressure. In other words, the pump is the heart
           of automatic transmissions. Most currently used pumps are rotary
           type, which has the same mechanism of operation, where the hydraulic
           medium (also, fluid) is trapped in chambers that are cyclically


                Pivot


               Slide
               Rotor

              Vane
           Vane ring
              Body
             Priming                            Figure 8.6 The pump schematic
                                                in automatic transmission [see
             spring                             Brejcha (1982)].
                Slide seal


                                                            #1 Side clearance
              #3 Ring        #2 Tip
                seal         seal
                               Cover



                     Ring                              Rotor
                             Vanes
                     bore
                              Body




                #9 Seal
                                        #5 Shaft seal
           Figure 8.7 Pump side view.
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