Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
  • F02F7/00—Casings, e.g. crankcases or frames
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B67/00—Engines characterised by the arrangement of auxiliary apparatus not being otherwise provided for, e.g. the apparatus having different functions; Driving auxiliary apparatus from engines, not otherwise provided for
  • F02B67/04—Engines characterised by the arrangement of auxiliary apparatus not being otherwise provided for, e.g. the apparatus having different functions; Driving auxiliary apparatus from engines, not otherwise provided for of mechanically-driven auxiliary apparatus
  • F02B67/06—Engines characterised by the arrangement of auxiliary apparatus not being otherwise provided for, e.g. the apparatus having different functions; Driving auxiliary apparatus from engines, not otherwise provided for of mechanically-driven auxiliary apparatus driven by means of chains, belts, or like endless members
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
  • F01L1/02—Valve drive
  • F01L1/024—Belt drive
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
  • F01L1/02—Valve drive
  • F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
  • F01L1/46—Component parts, details, or accessories, not provided for in preceding subgroups
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
  • F01L13/08—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for decompression, e.g. during starting; for changing compression ratio
  • F01L13/085—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for decompression, e.g. during starting; for changing compression ratio the valve-gear having an auxiliary cam protruding from the main cam profile
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B63/00—Adaptations of engines for driving pumps, hand-held tools or electric generators; Portable combinations of engines with engine-driven devices
  • F02B63/04—Adaptations of engines for driving pumps, hand-held tools or electric generators; Portable combinations of engines with engine-driven devices for electric generators
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
  • F02F7/00—Casings, e.g. crankcases or frames
  • F02F7/0043—Arrangements of mechanical drive elements
  • F02F7/0046—Shape of casings adapted to facilitate fitting or dismantling of engine parts
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L2303/00—Manufacturing of components used in valve arrangements
  • F01L2303/02—Initial camshaft settings
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B75/00—Other engines
  • F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
  • F02B75/18—Multi-cylinder engines
  • F02B2075/1804—Number of cylinders
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
  • F02F7/00—Casings, e.g. crankcases or frames
  • F02F7/0065—Shape of casings for other machine parts and purposes, e.g. utilisation purposes, safety
  • F02F7/0073—Adaptations for fitting the engine, e.g. front-plates or bell-housings
  • F02F2007/0075—Front covers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
  • F02F7/00—Casings, e.g. crankcases or frames
  • F02F7/0065—Shape of casings for other machine parts and purposes, e.g. utilisation purposes, safety
  • F02F7/0073—Adaptations for fitting the engine, e.g. front-plates or bell-housings
  • F02F2007/0078—Covers for belt transmissions

Definitions

• the present invention provides a drive rotary member fixed to the crankshaft and a slave fixed to the camshaft between the crankshaft supported by the crankcase and the valve camshaft supported by the cylinder head.
• the rotating and rotating members and the timing of the endless transmitting member force applied to both rotating members are connected via a transmission, and a working window is provided on one side of the cylinder head to attach and detach the driven rotating member to the camshaft.
• This relates to the improvement of the engine in which the lid that closes the working window is joined to the cylinder head.
• Patent Document 1 As disclosed in Patent Document 1, an engine having a high power is already known.
• Patent Document 1 Japanese Patent Laid-Open No. 10-54296
• the cylinder head has an outer end surface where the working window is open so that the outer end surface of the cylinder head is axially outward of the driven rotating member.
• the driven rotating member is placed in the back of the work window.
• the endless transmission member is attached to the driven rotating member and the driven rotating member is attached to the camshaft.
• the work is disturbed by the cylinder head around the driven rotating member, and the workability is poor.
• the entire lid that is joined to the outer end surface of the cylinder head inevitably causes the driven rotating member to move away in the axial direction, which hinders the compactness of the engine.
• the present invention has been made in view of the situation of force A, and has good workability such as mounting of an endless transmission member to a driven rotating member and mounting of a driven rotating member to a camshaft. It is an object of the present invention to provide a notable engine.
• the present invention provides a drive rotating member that is fixed to a crankshaft between a crankshaft supported by a crankcase and a valve camshaft supported by a cylinder head.
• the driven rotary member fixed to the camshaft and an endless transmission member that is strung over both rotary members are connected via a timing transmission device, and is connected to the outer end surface of the cylinder head to the camshaft of the driven rotary member.
• the outer end surface of the cylinder head to which the lid is joined is at least on the opposite side of the driven rotary member from the driven rotary member.
• a first feature is that a part of the outer periphery of the metal is formed on an inclined surface so that the working window force is exposed.
• the present invention is characterized in that the inclined surface is formed so that the driven window member is exposed to the working window force over a half circumference opposite to the drive rotating member. This is the second feature.
• the cylinder bore is connected to the crankcase, and a part of the timing transmission chamber on one side of which accommodates the timing transmission device is provided.
• the cylinder head is overlaid on the cylinder block with a gasket, and the cylinder head is fastened to the cylinder block with a plurality of main connecting bolts arranged around the cylinder bore.
• the third feature is that the cylinder head is fastened to the cylinder block by an auxiliary connecting bolt arranged in the cylinder.
• the present invention is characterized in that the side wall of the lid body is inclined so as to follow the inclined surface of the cylinder head. .
• the present invention is configured so that the first mark displayed on the outer surface of the driven rotating member coincides with the first mark when the crankshaft is at a predetermined rotational position.
• a second mark displayed on the engine body a bolt hole formed in the end wall of the hub of the driven rotary member, fitted to one end of the camshaft, a positioning groove extending radially from the bolt hole, a cam A positioning pin that protrudes from a center of one end surface of the shaft in a certain direction and engages with the positioning groove when the cam shaft is in a predetermined phase relationship with respect to the crank shaft at the predetermined rotation position;
• the cam shaft is also provided on one end surface of the cam shaft, and the cam shaft is at the predetermined rotational position.
• a screw hole that coincides with the bolt hole when in a predetermined phase relationship with respect to the rank shaft, and a mounting bolt that passes through the bolt hole and is screwed into the screw hole to fix the hub to the cam shaft.
• the present invention provides a straight line passing through the center of the crankshaft and the camshaft when the camshaft has a predetermined phase relationship with respect to the crankshaft at the predetermined rotational position.
• a sixth feature is that the first and second alignment marks, the positioning groove and the positioning pin are aligned.
• the present invention has a seventh feature in which the bolt hole and the screw hole are arranged at positions where the central forces of the hub and the camshaft are eccentric.
• the present invention is characterized in that, in addition to the seventh feature, the screw hole and the positioning pin are arranged at positions where the central forces of the cam shaft are also eccentric in opposite directions.
• the drive rotation member, the driven rotation member, and the endless transmission member respectively correspond to a drive pulley 45, a driven pulley 46, and a timing belt 47 in an embodiment of the present invention described later.
• a part of the driven pulley exposed outside the work window can be easily gripped with a tool or the like without being obstructed by the cylinder head.
• the pulley can be easily attached to the camshaft and removed easily. Therefore, it can contribute to the improvement of assemblability and maintainability.
• the operation of attaching and detaching the driven pulley to and from the camshaft can be performed more easily, so that the assembling property and the maintenance property can be further improved.
• the cylinder block and the cylinder head gasket are also secured around the timing transmission chamber by fastening the cylinder head to the cylinder block with the main connection bolt and the auxiliary connection bolt.
• the surface pressure can be increased sufficiently.
• a sufficient space for receiving the tool for operating the auxiliary connecting bolt is secured, so that the auxiliary connecting bolt can be easily tightened.
• the head of the engine body has a shape in which the lateral width is narrowed toward the front end side, so that the engine can be compact.
• the crankshaft is fixed at a rotational position corresponding to a specific position of the piston, and the first mark on the driven rotating member is aligned with the second mark on the engine body.
• the driven rotating member is inserted into the endless transmission member already hung on the driving rotating member, the positioning pin of the cam shaft is received in the bolt hole of the driven rotating member, and this positioning pin is guided to the positioning groove of the driven rotating member.
• the first and second alignment marks, the bolt holes and the screw holes, and the positioning grooves and the positioning pins are arranged all at once on a straight line passing through the centers of the crankshaft and camshaft. be able to.
• the crankshaft and camshaft are mounted on the engine body in advance.
• the timing transmission device is attached to the camshaft in the predetermined phase relationship, and the installation is easy and accurate.
• the first and second alignment marks, and the state where the positioning groove and the positioning pin are aligned on a straight line passing through the centers of the crankshaft and the camshaft are visually observed. This makes it easy to confirm that the crankshaft and camshaft are in a predetermined phase relationship.
• the rotation of the driven rotating member can be reliably transmitted to the camshaft via one eccentric mounting bolt, and the mounting bolt is prevented from loosening. be able to.
• a sufficient amount of eccentricity can be given to each of the bolt hole and the positioning groove formed in the narrow end wall of the hub of the driven rotating member, and therefore the positioning groove.
• the positioning effect on the positioning pins and the torque capacity of the mounting bolts can be increased.
• FIG. 1 is a longitudinal plan view of a general-purpose four-cycle engine according to the present invention. (First Example )
• FIG. 2 is a sectional view taken along line 2-2 of FIG. (First example)
• FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. (First example)
• FIG. 4 is an enlarged view of the periphery of the crankshaft in FIG. (First example)
• FIG. 5 is a view taken in the direction of arrow 5 in FIG. (First example)
• FIG. 6 is a sectional view taken along line 6-6 of FIG. (First example)
• FIG. 7 is a sectional view taken along line 7-7 of FIG. (First example)
• FIG. 8 is a sectional view taken along line 8-8 in FIG. (First example)
• FIG. 9 is a cross-sectional view taken along line 9 9 in FIG. (First example)
• FIG. 10 is a view taken in the direction of arrow 10 in FIG. (First example)
• Fig. 11 is a diagram corresponding to Fig. 10 with the driven pulley removed. (First example)
• FIG. 12 is an explanatory view of the installation procedure of the driven pulley to the camshaft. (First example)
• Timing transmission device 45 ⁇ ⁇ Drive rotating member (drive pulley)
• the engine body 1 of the general-purpose four-cycle engine E is integrally connected to the crankcase 2 having a mounting seat 2a at the lower portion and the crankcase 2 and is inclined upward.
• a cylinder block 3 having a cylinder bore 3a and a cylinder head 5 joined to the upper end surface of the cylinder block 3 via a gasket 4 are constituted as components, and the cylinder head 5 is joined to the cylinder block 3, that is, For fastening, four main connecting bolts 6, 6,... Arranged at four locations around the cylinder bore 3a and two auxiliary connecting bolts 7, 7 described later are used.
• the crankcase 2 is open on one side, and the opening surface force is also reduced on the inner peripheral wall. Is formed in a plurality of stepped portions 8, 8,... Aligned in the circumferential direction facing the open side, and the bearing bracket 10 is formed by a plurality of bolts 11, 11,. It is fixed.
• the bearing bracket 10 and the other side wall of the crankcase 2 support the opposite ends of the crankshaft 12 in a horizontal position via bearings 13 and 13 '. Further, the force at both ends of the balancer shaft 14 arranged adjacent to and parallel to the crankshaft 12 is also supported by the bearing bracket 10 and the other side wall of the crankcase 2 via bearings 15 and 15.
• a continuous reinforcing rib 16 is formed on the outer peripheral surface of the crankcase 2 so as to surround the plurality of stepped portions 8, 8, and so on.
• the end of the rib 16 is integrally connected to the outer wall of the cylinder block 3 integrated with the crankcase 2.
• the reinforcing rib 16 is connected to the inner plurality of step portions 8, 8 ... on the outer peripheral surface of the crankcase 2, so that the step portions 8, 8 ...
• the support rigidity of the supported bearing bracket 10 and thus the support rigidity of the crankshaft 12 by the bearing bracket 10 can be effectively enhanced.
• the crankcase 2 can be made thinner and lighter. it can.
• the reinforcing function of the reinforcing rib 16 is enhanced, and the support rigidity of the bearing bracket 10 can be further enhanced.
• a side cover 17 that closes an open surface on one side is joined to the crankcase 2 by a plurality of bolts 24, 24.
• One end of the crankshaft 12 protrudes outward as an output shaft through the side cover 17, and an oil seal 18 closely attached to the outer peripheral surface of the output shaft is attached to the side cover 17.
• crankshaft 12 penetrates the other side wall of the crankcase 2, and an oil seal 19 in close contact with the other end portion of the crankshaft 12 is provided on the outer side of the bearing 13 ⁇ .
• a flywheel 21 that also serves as a rotor of the generator 20 is fixed to the other end of the crankshaft 12, and a cooling fan 22 is attached to the outer surface of the flywheel 21.
• a recoil type starter 23 supported by the crankcase 2 is placed at the other end of the crankshaft 12.
• the crankshaft 12 is connected via a piston 25 force S connecting rod 26 fitted to the cylinder bore 3a.
• the cylinder head 5 has a fuel connected to the cylinder bore 3a.
• a combustion chamber 27 and an intake port 28i and an exhaust port 28e that open to the combustion chamber 27 are formed, and an intake valve valve that opens and closes the open ends of the intake and exhaust ports 28i and 28e to the combustion chamber 27, respectively.
• 29i and exhaust valve 29e are attached.
• the intake and exhaust valves 29i and 29e are equipped with valve springs 30i and 30e that urge them in the closing direction, respectively.
• the intake and exhaust valves 29i and 29e are driven to open and close by a valve gear 35 that cooperates with the valve springs 30i and 30e.
• valve gear 35 will be described with reference to FIGS. 3, 4, and 6 to 12.
• the valve operating device 35 includes a camshaft 36 that is supported by the cylinder head 5 in parallel with the crankshaft 12 and includes an intake cam 36i and an exhaust cam 36e, and the crankshaft 12 And the timing transmission 37 that connects the camshaft 36, the intake rocker arm 38i that links the intake cam 36i and the intake valve 29i, and the exhaust rocker arm 38e that links the exhaust cam 36e and the exhaust valve 29e.
• the cam shaft 36 includes a bag-shaped bearing hole 39 formed in one side wall 5a of the cylinder head 5 and a ball bearing 41 fitted in the bearing mounting hole 40 of the partition wall 5b in the middle of the cylinder head 5. Both ends are supported. Further, a common single stopper shaft 42 for swinging the intake and exhaust outlet arm 38i, 38e is provided in the first and second support holes 43 'formed in the one side wall 5a and the partition wall 5b, respectively. , 43 support both ends.
• the first support hole 43 ′ of the one side wall 5 a has a bag shape, and the second support hole 43 of the partition wall 5 b has a through hole shape.
• the outer end of the stopper shaft 42 is formed at the outer end of the second support hole 43.
• a fixing bolt 44 for abutting the tip thereof is screwed to the partition wall 5b. Therefore, the stopper shaft 42 is prevented from moving in the thrust direction by the bag-like first support hole 43 ⁇ and the fixing bolt 44.
• the fixing bolt 44 is integrally provided with a relatively large-diameter flange seat 44a in contact with the outer end surface of the outer race 41a of the ball bearing 41 that supports the camshaft 36 on the head.
• the thrust bolts 42 and the camshaft 36 are both thrust by a single fixing bolt 44. It is possible to prevent the movement in the direction, and the number of parts of the valve operating device 35 can be reduced and the structure can be simplified, contributing to the compactness of the valve operating device 35, and to improving the assembly of the device 35.
• the timing transmission device 37 includes a toothed drive pulley 45 fixed to the crankshaft 12 and a toothed drive pulley 45 fixed to the camshaft 36, the number of teeth of which is twice that of the drive pulley 45. 46 and an endless timing belt 47 wound around these driving and driven pulleys 45 and 46.
• the rotation of the crankshaft 12 is decelerated to 1 Z2 by the timing transmission device 37 and transmitted to the camshaft 36.
• the intake and exhaust cams 36i, 36e force intake and exhaust outlet cover arms 38i, 38e are swung against the urging forces of the valve springs 30i, 30e, respectively.
• Each 29e can be opened and closed.
• This timing transmission 37 includes a lower chamber 48a defined between the bearing bracket 10 and the side cover 17, an intermediate chamber 48b formed in the cylinder block 3 on one side of the cylinder bore 3a, and a cylinder head 5 It is accommodated in a timing transmission chamber 48 formed by sequentially connecting an upper chamber 48c formed on one side. That is, the driving pulley 45 is disposed in the lower chamber 48a, the driven pulley 46 is disposed in the upper chamber 48c, and the timing belt 47 is disposed so as to pass through the intermediate chamber 48b.
• the engine E can be made compact.
• the cylinder head 5 is formed with a valve chamber 49 having an open upper surface between the one side wall 5a and the partition wall 5b, and the intake and exhaust cams 36i of the cam shaft 36 are formed in the valve chamber 49. 36e, intake and exhaust outlet arm 38i, 38e, etc. are accommodated.
• the open upper surface of the valve operating chamber 49 is closed by a head cover 52 joined to the cylinder head 5 with bolts 53.
• the upper chamber 48c and the valve operating chamber 49 of the timing transmission chamber 48 are connected to an oil passage hole 75 provided in the partition wall 5b.
• the outer end surface 5c of the cylinder head 5 is provided with a working window 55 that opens the upper chamber 48c so that the outer surface of the driven pulley 46 faces, and the driven pulley is passed through the working window 55.
• 46 is inserted into the timing belt 47, and the driven pulley 46 is removed from the camshaft 36. Installation work is performed.
• a lid body 57 for closing the work window 55 is joined to the outer end surface 5c by a plurality of bolts 58 via a seal member 56.
• the outer end surface 5c of the cylinder head 5 to which the lid 57 is joined has at least a part of the outer periphery of the driven pulley 46 on the side opposite to the drive pulley 45.
• the inclined surface 5c is preferably inclined so as to be exposed from the working window 55 over a half circumference opposite to the driving pulley 45 of the driven pulley 46.
• the driven pulley 46 includes a bottomed cylindrical hub 46a, a web 46b extending in a radial direction from the hub 46a, and a toothed rim formed on the outer periphery of the web 46b.
• the hub 46a is fitted to the outer periphery of the outer end of the camshaft 36 protruding toward the upper chamber 48c.
• the end wall of the hub 46a is provided with a bolt hole 60 that occupies a position where the central force is also eccentric, and a positioning groove 61 that extends from one side of the bolt hole 60 to the opposite side to the eccentric direction.
• a first mark 62a is engraved on the outer surface of the rim 46c, and a second mark 62b corresponding to the first mark 62a is engraved on the outer end surface 5c of the cylinder head 5.
• the web 46b is provided with a plurality of through holes 64, 64 penetrating therethrough.
• a screw hole 66 corresponding to the bolt hole 60 and a positioning pin 67 corresponding to the positioning groove 61 are provided at the outer end portion of the cam shaft 36. It is done.
• crankshaft 12 is at a predetermined rotation position corresponding to a specific position (for example, top dead center) of the piston 25, and the camshaft 36 is at a predetermined phase relationship position with respect to the crankshaft 12.
• first and second marks 62a and 62b, bolt hole 60 and screw hole 66, positioning groove 61 and positioning pin 67 are aligned with each other on a straight line L passing through the centers of both shafts 12 and 36, There is.
• the crankshaft 12 is fixed at a rotational position corresponding to the specific position of the piston 25.
• the timing belt 47 that is already hung on the drive pulley 45 while the first pulley 62a of the rim 46c is aligned with the second drum 62b of the cylinder head 5 is aligned. Insert inside.
• the positioning pin 67 of the camshaft 36 is received in the bolt hole 60 of the driven pulley 46 and the positioning pin 67 is guided to the positioning groove 61 so as to be driven.
• the positioning pin 67 received in the bolt hole 60 is guided to the positioning groove 61, and the first and second alignments are made on a straight line L passing through the centers of the crankshaft 12 and the camshaft 36.
• the marks 62a and 62b, the bolt hole 60 and the screw hole 66, the positioning groove 61 and the positioning pin 67 are arranged all at once. By visually observing this state, it can be easily confirmed that the crankshaft 12 and the camshaft 36 are in a predetermined phase relationship.
• the hub 46 a is fixed to the camshaft 36 by passing the mounting bolt 68 through the bolt hole 60, screwing into the screw hole 66, and tightening.
• the timing transmission 37 is attached to the crankshaft 12 and the camshaft 36 that are previously mounted on the crankcase 2 and the cylinder head 5 in the predetermined phase relationship.
• the screw hole 66 and the positioning pin 67 are arranged at positions where the central forces of the cam shaft 36 are also eccentric in opposite directions, so that the bolt hole 60 formed in the narrow end wall of the hub 46a of the driven pulley 46 is provided.
• a sufficient amount of eccentricity can be given to the positioning groove 61, whereby the positioning effect of the positioning groove 61 on the positioning pin 67 and the torque capacity of the mounting bolt 68 can be increased.
• the outer end surface of the cylinder head 5 in which the work window 55 is opened becomes the inclined surface 5c !, so that a part of the outer periphery of the driven pulley 46 is exposed from the work window 55. Therefore, a part of the driven pulley 46 exposed outside the work window 55 can be easily grasped with a tool or the like without being obstructed by the cylinder head 5, and the cam of the driven pulley 46 is thereby It can be easily attached to the shaft 36 and can be easily removed. Therefore It can contribute to the improvement of assemblability and maintainability.
• the outer end surface 5c of the cylinder head 5, that is, the side wall 73 of the lid 57 joined to the inclined surface 5c is formed so as to be inclined along the inclined surface 5c.
• the head of the engine body 1 is shaped so that its lateral width narrows toward the tip side, and the engine E can be made compact.
• the cylinder head 5 is formed with a pair of projecting portions 70, 70 projecting outward from the work window 55 below the work window 55.
• the portions 70 and 70 are overlapped on the upper end surface of the cylinder block 3 outside the intermediate chamber 48b through the gasket 4 and fastened to the cylinder block 3 by auxiliary connecting bolts 7 and 7.
• the surface of the cylinder block 3 and the cylinder head 5 with respect to the gasket 4 is located outside the intermediate chamber 48b accommodating the timing belt 47!
• the pressure can be increased sufficiently.
• the presence of the inclined surface 5c above the auxiliary connecting bolts 7 and 7 ensures a sufficient space for receiving the tool for operating the auxiliary connecting bolts 7 and 7. Can be easily performed. This also means that the amount of overhanging of the projecting portions 70, 70 to the outside of the work window 55 can be reduced, which also contributes to the compactness of the engine E.
• the lower chamber 48a of the timing transmission chamber 48 passes through a plurality of step portions 8, 8 ... of the inner wall of the crankcase 2 that supports the bearing bracket 10.
• the crankcase 2 communicates with the inside of the crankcase 9, that is, the crankcase 9.
• an impeller-type oil slinger 72 driven from the crankshaft 12 via gears 74 and 74 ' is partly stored in the lower chamber 48a. It is arranged so as to be immersed in.
• the oil slinger 72 causes the oil 71 to scatter to the surroundings by its rotation.
• the oil guiding wall 73 forces the oil slinger 72 and the drive pulley 45 side to guide the scattered oil to the timing belt 47 side.
• the timing belt 47 is integrally formed on the outer surface of the bearing bracket 10 so as to surround the periphery thereof. Bearing block Since the racket 10 is a relatively small part, it can be easily manufactured together with the oil guide wall 73. Also, the bearing bracket 10 has the oil guide wall 73 integrally therewith, so that its rigidity is strengthened and effective in increasing the support rigidity of the crankshaft 12.
• the scattered oil from the oil slinger 72 is guided to the timing belt 47 side by the oil guide wall 73, and the oil adhering to the timing belt 47 is transferred to the upper chamber by the belt 47.
• the timing belt 47 reaches the driven pulley 46 when it is transported to 48c, it is swung off by centrifugal force and scattered to the surroundings, colliding with the surrounding walls to generate oil mist, which is generated in the upper chamber 48c.
• the ball bearing 41 of the camshaft 36 can be lubricated as well as the entire timing transmission 37.
• the bottom of the valve operating chamber 49 is connected to the crank chamber via a series of oil return passages 77 formed in the cylinder head 5 and the cylinder block 3 along one side of the cylinder bore 3a. Communicated with 9 The oil return passage 77 descends toward the crank chamber 9 so that oil flows from the valve chamber 49 to the crank chamber 9.
• the oil accumulated in the valve operating chamber 49 flows down the oil return passage 77 and returns to the crank chamber 9.
• the bottom of the timing transmission chamber 48 is also directed downward to the lower chamber 48a.
• the oil accumulated in the upper chamber 48c flows down the intermediate chamber 48b and returns to the lower chamber 48a.
• the inside of the timing transmission chamber 48 and the valve chamber 49 that are partitioned from each other can be lubricated by the oil mist. This eliminates the need for a dedicated oil pump for lubrication, contributing to the simplification and compactness of the engine E structure and cost reduction. Since the camshaft 36 can maintain the overhead position with respect to the intake and exhaust valves 29i and 29e, the desired output performance of the engine can be ensured.
• the belt type timing transmission 37 can be replaced with a chain type.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Valve-Gear Or Valve Arrangements (AREA)
• Cylinder Crankcases Of Internal Combustion Engines (AREA)
• Valve Device For Special Equipments (AREA)

Priority Applications (6)

Applications Claiming Priority (4)

Publications (1)

Family

ID=37570536

Family Applications (1)

Country Status (13)

Cited By (1)

Families Citing this family (2)

Citations (3)

Family Cites Families (4)

• 2006
  • 2006-05-26 TW TW095118775A patent/TWI318660B/zh not_active IP Right Cessation
  • 2006-06-15 MY MYPI20062837A patent/MY142921A/en unknown
  • 2006-06-21 PE PE2006000695A patent/PE20070129A1/es not_active Application Discontinuation
  • 2006-06-22 AR ARP060102678A patent/AR054794A1/es active IP Right Grant
  • 2006-06-23 AU AU2006260106A patent/AU2006260106B2/en not_active Ceased
  • 2006-06-23 DE DE602006011315T patent/DE602006011315D1/de active Active
  • 2006-06-23 ES ES06780645T patent/ES2337182T3/es active Active
  • 2006-06-23 KR KR1020077027103A patent/KR100947005B1/ko not_active IP Right Cessation
  • 2006-06-23 EP EP06780645A patent/EP1895135B1/de not_active Expired - Fee Related
  • 2006-06-23 CA CA2606776A patent/CA2606776C/en not_active Expired - Fee Related
  • 2006-06-23 PA PA20068682301A patent/PA8682301A1/es unknown
  • 2006-06-23 BR BRPI0613155-7A patent/BRPI0613155A2/pt not_active IP Right Cessation
  • 2006-06-23 WO PCT/JP2006/312608 patent/WO2006137519A1/ja active Application Filing

Patent Citations (3)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events