Cylinder head fastening structure for internal combustion engines

Abstract

An improved cylinder head fastening arrangement for an internal combustion engine that permits location of overhead cam shafts directly over the cylinder head fasteners. The cam shafts are formed with access openings that extend through them which permit a tool to be passed for tightening of the cylinder head fasteners without removal of the cam shaft.

We claim: 
     
       1. In a construction for an overhead cam internal combustion engine comprising a cylinder head adapted to be affixed to another component of the engine by at least one fastener, the improvement comprising a cam shaft journaled for rotation relative to said cylinder head, said cam shaft being positioned in overlying relationship to said fastener and means defining an access opening passing through said cam shaft and adapted to pass a tool for tightening said fastener without removal of said cam shaft. 
     
     
       2. A construction for an overhead cam internal combustion engine as set forth in claim 1 wherein the cam shaft is rotatably journaled by the cylinder head. 
     
     
       3. A construction for an overhead cam internal combustion engine as set forth in claim 2 wherein the access opening passes through an area of the cam shaft where said cam shaft is journaled by the cylinder head. 
     
     
       4. A construction for an overhead cam internal combustion engine as set forth in claim 3 further including means for delivering lubricant to the access opening for lubricating the cam shaft journal. 
     
     
       5. A construction for an overhead cam internal combustion engine as set forth in claim 1 further including means formed on the cam shaft for facilitating rotation of the cam shaft to align the access opening with the fastener. 
     
     
       6. A construction for an overhead cam internal combustion engine as set forth in claim 5 wherein the means for facilitating turning of the cam shaft comprises a hexagonal portion formed on the cam shaft. 
     
     
       7. A construction for an overhead cam internal combustion engine as set forth in claim 1 wherein there are a pair of cam shafts positioned on opposite sides of the cylinder head and fastening means positioned beneath each of the cam shafts, each cam shaft having an access opening adapted to pass a tool for tightening the fastener without removal of the respective cam shaft. 
     
     
       8. A construction for an overhead cam internal combustion engine as set forth in claim 7 wherein the cam shafts are rotatably journaled by the cylinder head. 
     
     
       9. A construction for an overhead cam internal combustion engine as set forth in claim 8 wherein the access openings pass through an area of the cam shafts where said cam shafts are journaled by the cylinder head. 
     
     
       10. A construction for an overhead cam internal combustion engine as set forth in claim 9 further including means for delivering lubricant to the access openings for lubricating the cam shaft journals. 
     
     
       11. A construction for an overhead cam internal combustion engine as set forth in claim 10, further including means formed on at least one of the cam shafts for facilitating rotation of the cam shafts to align the access openings with the fasteners. 
     
     
       12. A construction for an overhead cam internal combustion engine as set forth in claim 11 wherein the means for facilitating turning of the cam shaft comprises a hexagonal portion formed on the cam shaft. 
     
     
       13. A construction for an overhead cam internal combustion engine as set forth in any of the preceding claims wherein the fastening means comprises a threaded fastener. 
     
     
       14. A construction for an overhead cam internal combustion engine as set forth in claim 13 wherein the threaded fastener has a socket opening adapted to receive the tool. 
     
     
       15. A construction for an overhead cam internal combustion engine as set forth in claim 1 wherein there are a plurality of longitudinally spaced fasteners and the cam shaft has access openings associated with each of the fasteners, the cam shaft being rotatably supported by the cylinder head through bearing portions juxtaposed to the respective of the fasteners, the cam shaft having a longitudinally extending lubricating passage intersecting the access openings and further including means for delivering lubricant to said lubricant passage for lubricating the cam shaft bearing portion through the access openings. .Iadd. 
     
     
       16.  A construction for an overhead cam internal combustion engine as set forth in claim 3 wherein the cam shaft is journaled by means of a bearing cap affixed to the cylinder head and an access opening is formed in the bearing cap aligned with the access opening in the cam shaft for passing the tool for tightening the fastener. .Iaddend. .Iadd.17. A construction for an overhead cam internal combustion engine as set forth in claim 16 further including closure means for closing the access opening in the bearing cap. .Iaddend. .Iadd.18. A construction for an overhead cam internal combustion engine as set forth in claim 17 further including a cam cover affixed to the cylinder head and enclosing the cam shaft, the cam cover having a portion thereof engaging the closure and holding the closure in the bearing cap access opening. .Iaddend. .Iadd.19. A construction for an overhead cam internal combustion engine as set forth in claim 9 wherein the cam shafts are journaled by the cylinder head by means including bearing caps affixed to the cylinder head, each of the bearing caps having an access opening aligned with the respective cam shaft access opening for passing the tool for tightening the fastener. .Iaddend. .Iadd.20. A construction for an overhead cam internal combustion engine as set forth in claim 19 further including closure means received in the bearing cap access openings for closing the bearing cap access openings. .Iaddend. .Iadd.21. A construction for an overhead cam internal combustion engine as set forth in claim 20 further including a cam cover affixed to the cylinder head and enclosing the cam shafts, the cam cover having means engaging the closures for maintaining the closures in the 
     
     
        bearing cap access openings. .Iaddend. .Iadd.22.  In a construction for an overhead cam internal combustion engine comprising a cylinder head adapted to be affixed to another component of the engine by at least one fastener having a tool receiving portion for tightening thereof and having a bearing cap affixed to the cylinder head and rotatably journaling the overhead camshaft, the improvement comprising said bearing cap having a portion overlying said fastener tool receiving portion, and means defining an access opening passing through said bearing cap and adapted to pass a tool for tightening of said fastener without removal of said bearing cap. .Iaddend. .Iadd.23. A construction for an overhead cam internal combustion engine as set forth in claim 22 further including closure means for closing the access opening in the bearing cap. .Iaddend. .Iadd.24. A construction for an overhead cam internal combustion engine as set forth in claim 23 further including a cam shaft cover affixed to the cylinder head and enclosing the cam shaft and bearing cap. .Iaddend. .Iadd.25. A construction for an overhead cam internal combustion engine as set forth in claim 24 wherein the cam cover has a surface engaged with the closure for retaining the closure in the bearing cap access opening. .Iaddend. .Iadd.26. A construction for an overhead cam internal combustion engine as set forth in claim 22 wherein the cylinder head is affixed to a cylinder 
     
     
        block. .Iaddend. .Iadd.27.  A construction for an overhead cam internal combustion engine as set forth in claim 26 wherein the cylinder head is affixed to the cylinder block by fastening means formed on opposite sides of the cylinder block, the cam shaft being positioned over one series of the fastening means at one side of the cylinder block and further including a further cam shaft positioned on the other side of the cylinder block and overlying the other series of fastener means, said other cam shaft being rotatably journaled by bearing caps having portions overlying the other series of fastener means and having access openings passing therethrough and adapted to pass a tool for tightening the second series of fastener means without removal of the bearing cap. .Iaddend. .Iadd.28. A construction for an overhead cam internal combustion engine as set forth in claim 27 wherein the cam shafts are further rotatably journaled by bearing surfaces formed directly in the cylinder head. .Iaddend. .Iadd.29. A construction for an overhead cam internal combustion engine as set forth in claim 28 further including closure means received in the bearing cap access openings for closing said access openings. .Iaddend. .Iadd.30. A construction for an overhead cam internal combustion engine as set forth in claim 29 further including cam cover means affixed to the cylinder head and overlying and enclosing the cam shafts and the bearing caps. .Iaddend. .Iadd.31. A construction for an overhead cam internal combustion engine as set forth in claim 30 wherein the cam cover means has surfaces engaged with the closures for retaining the closures in the cam shaft bearing cap access openings. .Iaddend.