Interlocking construction in transmission manipulation device for manual transmission

In a transmission having a transmission case, a first fork shaft and a second fork shaft axially movably and corotatably mounted on said transmission case, a plurality of shift forks axially movably and rotatably mounted on said first fork shaft, said shift forks having engaging portions aligned in a direction perpendicular to the fork shafts, a shift and select lever shaft axially movably and rotatably carried by said transmission case and extending in the direction perpendicular to said first and second fork shafts, a resilient member biasing said lever shaft towards a neutral position, a first projection provided on said lever shaft selectively engageable with the engaging portion of one of said shift forks, a first shift head fixed to said first fork shaft and having an engaging portion adjacent to said engaging portions of said shift forks, a second projection provided on said lever shaft engageable with the engaging portion of said first shift head only when said first projection is in engagement with the engaging portion of any one of said shift forks on said first fork shaft, a single shift fork fixed to said second fork shaft and having an engaging portion adjacent to said engaging portions of said shift forks attached to said first fork shaft, said first projection on said lever shaft being selectively engageable with the engaging portion of said second shift head, an interlocking construction comprising:

• an interlocking plate rotatably provided on said lever shaft but prevented from rotating with respect to said case, said interlocking plate comprising front and rear projections engageable with the engaging portions of said shift forks on said first fork shaft which are not engaged by said first projection, as well as with the engaging portion of said second shift head, when said second projection is engaged by said engaging portion of said first shift head, and engageable with the engaging portions of all shift forks on said first fork shaft, as well as the engaging portion of said first shift head, when said second projection is not engaged with the first shift head.