JP6285768B2 - Locker arm dropout prevention mechanism - Google Patents

Description

  The present invention relates to a rocker arm dropout prevention mechanism, and more particularly to a rocker arm dropout prevention mechanism that prevents the rocker arm from falling off during assembly of an engine.

  For example, in a valve mechanism of an engine, a rocker arm pivot is protruded from a cylinder head, and a rocking fulcrum of a rocker arm is supported by the top of the rocker arm pivot. The camshaft cam is brought into contact with a slipper portion or a roller formed in an intermediate portion of the rocker arm. When this camshaft rotates, the rocker arm swings and opens and closes the valve with the swinging fulcrum supported on the top of the rocker arm pivot as a fulcrum. Also, there is a type in which a valve adjusting screw whose tip is in contact with the top of the rocker arm pivot is attached to the rocking fulcrum of the rocker arm, and the valve clearance is adjusted by the valve adjusting screw.

  In assembling such a valve mechanism, a rocker arm pivot, a valve, and the like are assembled in advance to the cylinder head. Place the rocker arm swing fulcrum or the tip of the valve adjustment screw on the top of the assembled rocker arm pivot, and set the rocker arm with the rocking end on the valve stem top. The cam carrier, to which the camshaft is attached in advance, is positioned so that the cam comes into contact with the slipper portion or roller of the rocker arm and is mounted on the cylinder head.

  Here, in the state where the rocker arm is supported on the top of the rocker arm pivot and the top end of the valve stem, the cam carrier with the camshaft is assembled to the cylinder head, so that the set rocker arm falls off before assembling the cam carrier. There is concern. In particular, when assembling a horizontally opposed engine in which the axis of the cylinder bore is positioned on a horizontal plane or an engine in which the axis of the cylinder bore is greatly inclined, the rocker arm may drop off.

  On the other hand, various configurations for preventing the rocker arm from falling off have been proposed. For example, in Patent Document 1, a pivot formed at the tip of a valve adjustment screw provided at one end of a rocker arm is held at the top of the rocker arm pivot by a cap made of an elastic body having a hole having a smaller diameter than the pivot. A valve mechanism is disclosed.

  Patent Document 2 discloses a valve clearance adjusting device that presses and holds a swing support portion on a cylinder head by a holding spring attached to a cylinder head so that a swing fulcrum portion of the rocker arm does not float from the top of the rocker arm pivot. Disclosed.

  Patent Document 3 discloses a rocker arm holding device that holds a rocking fulcrum portion of a rocker arm on the top of a rocker arm pivot by a cap made of a spring material.

  In Patent Document 4, a spherical body is formed at the tip of a valve adjustment screw provided at one end of a rocker arm, while the top of the rocker arm pivot is formed into a concave spherical surface corresponding to the spherical body, and the spherical body is engaged with the concave spherical surface. In addition, there is disclosed a rocker arm mounting structure in which an elastic member for holding the spherical body on the concave spherical surface of the rocker arm pivot is provided at the end of the concave spherical opening.

Japanese Utility Model Publication No. 3-420022 Japanese Utility Model Publication No. 61-122306 Japanese Utility Model Publication No. 1-25409 JP 61-81502 A

  According to Patent Document 1, the rocker arm can be prevented from falling off by holding the pivot formed at the tip of the valve adjustment screw by the cap attached to the rocker arm pivot. However, it is extremely troublesome to fit the cap on the tip of the valve adjustment screw and fit the cap to the rocker arm pivot between the rocker arm and the rocker arm pivot.

  According to Patent Document 2, the rocker arm can be prevented from falling off by pressing and holding the rocking fulcrum of the rocker arm by the holding spring attached to the cylinder head. However, the operation of bolting the holding spring having a complicated shape to the cylinder head is troublesome and there is a concern that the valve operating device may be complicated. In addition, the holding spring having a complicated shape and a troublesome mounting operation cause a decrease in productivity and an increase in manufacturing cost.

  According to Patent Document 3, it is possible to prevent the rocker arm from falling off by holding the rocking fulcrum portion of the rocker arm on the rocker arm pivot with a cap made of a spring material. However, it is troublesome to attach the cap made of the spring material to the cylinder head, and there is a concern that the valve mechanism is complicated. In addition, the cap having a complicated shape and a complicated mounting operation of the cap cause a decrease in productivity and an increase in manufacturing cost.

  According to Patent Document 4, the rocker arm can be prevented from falling off by engaging the spherical body of the valve adjusting screw provided at one end of the rocker arm with the concave spherical surface formed at the top of the rocker arm pivot and holding it with an elastic member. However, it is troublesome to attach the elastic body between the rocker arm and the rocker arm pivot by holding the spherical body of the valve adjustment screw on the concave spherical surface of the rocker arm pivot.

  Accordingly, an object of the present invention made in view of such a point is to provide a rocker arm drop prevention mechanism capable of preventing a rocker arm from falling off with a simple structure without complicated construction and troublesome attachment work. .

The rocker arm drop prevention mechanism according to claim 1, which achieves the above object, is provided in a rocker arm drop prevention mechanism in which a rocking fulcrum is supported on the top of a rocker arm pivot attached to a cylinder head of an engine. Is provided with a lubricating oil supply hole that opens at the top, and the rocking fulcrum is supported by the rocking fulcrum of the rocker arm pivoted on the top of the rocker arm pivot. A concave portion for forming a space is provided in a portion facing the opening, and a concave portion further depressed is formed in the central portion of the concave portion. In the supported state, the concave portion is formed in the lubricating oil supply hole from the opening. in a state where one end and the other end is inserted it is projected, comprising a Kakaritomete stage restraining the positional deviation from the top of the swing fulcrum portion in the one end inserted state The locking means is formed of a shaft-shaped member, the base end which is the one end is locked and fixed in the lubricating oil supply hole, and the tip which is the other end is a straight line having no protrusion on the peripheral surface. And it is the state inserted in the concave part of the said rocking | fulcrum fulcrum part, It is characterized by the above-mentioned.

When the locking means is supported, one end is in the opening of the lubricating oil hole and the other end protrudes from the opening. Therefore, when the rocking fulcrum part and the top part are displaced relative to each other, the locking means is locked at the same time as the opening of the lubricating oil supply hole and the rocking fulcrum part, thereby preventing the mutual displacement. can do. The locking means is partially inserted in a state where the swing fulcrum is supported on the top , and is attached to the rocker arm pivot side . Accordingly, the rocker arm is supported by superimposing the rocker arm swinging fulcrum on the top of the rocker arm pivot, thereby preventing the displacement and preventing the rocker arm from falling off. Therefore, the rocker arm can be prevented from falling off with a simple configuration without complicated configuration and troublesome mounting work.

Also, according to this, a concave portion that faces the opening of the lubricating oil supply hole is formed in the swing fulcrum portion, and one end of the shaft-like member that becomes the locking means in the supported state is engaged and supported by the lubricating oil supply hole. Thus, the rocker arm can be prevented from falling off by engaging the other end with the recess.

According to a second aspect of the present invention, in the rocker arm drop prevention mechanism according to the first aspect, the shaft-shaped member is cylindrical.

According to a third aspect of the present invention, in the rocker arm drop prevention mechanism in which a rocking fulcrum is supported on the top of the rocker arm pivot attached to the cylinder head of the engine, the rocker arm pivot is supplied with lubricating oil that opens to the top. A hole is provided, and the rocker arm swinging fulcrum is supported on the top of the rocker arm pivot, and one end is inserted into the lubricating oil supply hole and the other end protrudes, A locking means for preventing displacement of the swing fulcrum from the top in a state of being inserted at one end, and the top of the rocker arm pivot has a concave spherical bearing surface in which the lubricating oil supply hole opens; The swing fulcrum portion includes a valve adjusting screw whose tip is slidably in contact with the support surface, and the locking means is formed of a shaft-shaped member, The base end, which is the end, is supported by the tip of the valve adjustment screw, and the tip, which is the one end, is a straight line having no protrusion on the peripheral surface, and the opening is formed in the lubricating oil supply hole formed in the bearing surface. It is characterized by being inserted from.

  According to this, the shaft-shaped member is provided at the tip of the valve adjusting screw provided at the swing fulcrum portion, and the rocker arm can be prevented from falling off by inserting and locking the shaft-shaped member into the lubricating oil supply hole in the supported state.

  According to the present invention, the rocker arm pivot is supported on the top of the rocker arm pivot so that the rocker arm is supported, so that the rocker arm is prevented from falling off and held at the support position. Therefore, the rocker arm can be prevented from falling off with a simple configuration without complicated configuration and troublesome mounting work.

It is a figure explaining the valve operating mechanism of the engine which concerns on 1st Embodiment. It is a schematic explanatory drawing of the valve operating mechanism on the intake port side. It is a schematic explanatory drawing of the valve mechanism on the exhaust port side. It is a schematic explanatory drawing of the valve operating mechanism by the side of an intake port concerning a 2nd embodiment. It is a schematic explanatory drawing of the valve mechanism on the exhaust port side. It is a general | schematic explanatory drawing of the valve operating mechanism by the side of the intake port which concerns on 3rd Embodiment. It is a schematic explanatory drawing of the valve mechanism on the exhaust port side. It is a schematic explanatory drawing of the valve mechanism by the side of the intake port which concerns on 4th Embodiment. It is a schematic explanatory drawing of the valve mechanism on the exhaust port side.

  Embodiments of a rocker arm drop-off prevention mechanism according to the present invention will be described below with reference to the drawings.

(First embodiment)
A first embodiment of a rocker arm drop prevention mechanism according to the present invention will be described with reference to FIGS.

  FIG. 1 is an explanatory view for explaining a valve operating mechanism of a horizontally opposed engine or a tilted engine in which the axis of a cylinder bore is located on a horizontal plane. An intake valve 5, an exhaust valve 7, rocker arms 11 and 21, a rocker arm pivot are provided on the cylinder head 1. 31, 35, camshafts 41, 43 and the like.

  In the cylinder head 1, the combustion chamber ceiling 2 is recessed in the cylinder mating surface, and the end of the intake port 3 and the end of the exhaust port 4 are opened in the combustion chamber ceiling 2. The intake valve 5 and the exhaust valve 7 are reciprocally supported so as to open and close the ends of the intake port 3 and the intake port 4, respectively, and are urged in the valve closing direction by the valve springs 5a and 7a. Is done.

  A camshaft 41 having a cam 42 for driving the intake valve 5 and the exhaust valve 7 and a camshaft 43 having a cam 44 are arranged in parallel at the upper portion of the cylinder head 1. Not supported by the cam carrier.

  The rocker arm 11 constituting the valve operating mechanism on the intake port 3 side is interposed between the camshaft 41 and the valve stem top portion 6 of the intake valve 5, and the rocker arm pivot having the swing fulcrum portion 12 provided on the cylinder head 1. The swing end 16 is supported by the top 33 of the cylinder 31 and extends so as to face the valve stem top 6 of the intake valve 5. The roller 17 is supported at an intermediate position between the swing fulcrum portion 12 and the swing end portion 16 so as to face the cam 42. According to the rotation of the camshaft 41, the swing end 16 side is swung around the swing fulcrum portion 12 by the cam 42, and the intake valve 5 is opened and closed.

  The rocker arm 21 constituting the valve mechanism on the exhaust port 4 side is interposed between the camshaft 43 and the valve stem top portion 8 of the exhaust valve 7, and the rocker arm pivot having the swing fulcrum portion 22 provided on the cylinder head 1. The swinging end portion 26 is supported by the top portion 37 of the 35 and extends so as to face the valve stem top portion 8 of the exhaust valve 7. A roller 27 is supported at an intermediate position between the swing fulcrum portion 22 and the swing end portion 26 so as to face the cam 44.

  In assembling these valve mechanisms, the rocker arm pivots 31 and 35, the intake valve 5, the exhaust valve 7 and the like are assembled to the cylinder head 1 in advance. The rocker arm 11 is set by overlapping the rocking fulcrum part 12 and the rocking end 16 on the top 33 of the rocker arm pivot 31 and the valve stem top 6 of the intake valve 5 assembled to the cylinder head 1. Similarly, the rocker arm 21 is set by superimposing the rocking fulcrum 22 and the rocking end 26 of the rocker arm 21 on the top 37 of the rocker arm pivot 35 and the valve stem top 8 of the exhaust valve 7.

  With the rocker arms 11 and 21 supported, a cam carrier (not shown) to which the camshafts 41 and 43 are attached can come into contact with the rollers 17 and 27 attached to the rocker arms 11 and 21 by the cams 42 and 44. Position and attach to the Linderhead 1.

  As shown in FIG. 2A, the rocker arm pivot 31 constituting the valve operating mechanism on the intake port 3 side has a base portion 32 that can be inserted into a pivot mounting hole 9 formed in the cylinder head 1 and a convex spherical bearing. The surface 33a is formed in a substantially cylindrical shape having a top portion 33, and a lubricating oil supply hole 34 opens in the support surface 33a. The lubricating oil supply hole 34 communicates with an annular oil passage 32 a formed on the outer peripheral surface of the base 32, and the oil passage 32 a communicates with a cylinder head side oil passage 9 a formed in the cylinder head 1.

  On the other hand, the rocking fulcrum portion 12 of the rocker arm 11 is formed in a concave spherical surface that is slidable in an annular shape surrounding the lubricating oil supply hole 34 on a bearing surface 33a formed on the top portion 33 of the rocker arm pivot 31 along the outer periphery. The bearing surface 13 and the supported surface 13 are formed in a substantially concave spherical shape having a concave portion 14 that forms a space for an oil reservoir between the bearing surface 33a of the top portion 33 and the bearing surface 33a. A concave portion 15 into which an end portion of a shaft-like member 19 serving as a locking means described later can be inserted is formed in the central portion of the concave portion 14.

  Further, the base end 19a serving as one end can be inserted into the lubricating oil supply hole 34 of the rocker arm pivot 31 to be locked and fixed, and the distal end 19b serving as the other end protrudes from the bearing surface 33a when inserted into the lubrication supply hole 34. A shaft portion 19 is provided. The shaft-shaped member 19 preferably has, for example, a circular arc shape or a cylindrical shape that can ensure an oil passage without sealing the lubrication supply hole 34 when the base end 19a is inserted into the lubrication supply hole 34.

  When mounting the rocker arm 11, the base end 19 a of the shaft-like member 19 is inserted into the lubricating oil supply hole 34 that opens to the top 33 of the rocker arm pivot 31, and the tip 19 b is mounted so as to protrude from the top 33.

  Further, as shown in FIG. 2B, the supported surface 13 is supported by inserting the tip 19b of the shaft-like member 19 protruding from the top 33 of the rocker arm pivot 31 into the recess 14 formed in the swing fulcrum portion 12. The rocker arm 11 is supported by overlapping the surface 33a and supporting the rocker end 11 with the swinging end portion 16 overlapping the valve stem top portion 6 of the intake valve 5. The rocker arm 11 spanned between the top portion 33 of the rocker arm pivot 31 and the valve stem top portion 6 of the intake valve 5 is provided on the tip 19b of the shaft-like member 19 provided on the rocker arm pivot 31, and the recess 14 of the swing fulcrum portion 12 is provided. The recessed portion 15 is locked and is prevented from being displaced and held in the support position without falling off.

  As shown in FIG. 3A, the rocker arm pivot 35 constituting the valve operating mechanism on the exhaust port 4 side has a base portion 36 that can be inserted into a pivot mounting hole 10 formed in the cylinder head 1 and a convex spherical shape. The bearing surface 37a is formed in a substantially cylindrical shape having a top portion 37, and a lubricating oil supply hole 38 is opened in the bearing surface 37a. The lubricating oil supply hole 38 communicates with an oil passage 36 a formed on the outer peripheral surface of the base portion 37, and the oil passage 36 a communicates with a headrest side oil passage 10 a formed in the cylinder head 1.

  On the other hand, the rocking support point 22 of the rocker arm 21 is a concave spherical and annular supported surface 23 which can be slidably contacted with the bearing surface 37 a of the rocker arm pivot 35 and surrounding the lubricating oil supply hole 38, and the supported surface 23. It is formed in a substantially concave spherical shape having a recess 24 inside. A concave portion 25 into which an end portion of the shaft-like member 29 serving as a locking means can be inserted is formed in the central portion of the concave portion 24. In attaching the rocker arm 21, the base member 29 is mounted by inserting the base end 29 a, which is one end of the shaft member 29, into the lubricating oil supply hole 38 that opens to the top 37 of the rocker arm pivot 35.

  Further, as shown in FIG. 3B, the tip 29b of the shaft-shaped member 29 protruding from the top 38 of the rocker arm pivot 35 is inserted into the recessed portion 24 or the recessed portion 25 formed in the swing fulcrum portion 22 to be supported. The rocker arm 11 is supported with the surface 23 superimposed on the bearing surface 37 a of the top surface 37 and the rocking end portion 26 superimposed on the valve stem top 8 of the exhaust valve 7. The rocker arm 21 is supported at the support position without falling off because the recesses 24 to 25 of the swing fulcrum 22 are locked to the tip 29b of the shaft-like member 29 provided on the rocker arm pivot 35, and the displacement is restrained. Retained.

  In this way, the rocker arm 11 is supported on the top 33 of the rocker arm pivot 31 and the valve stem top 6 of the intake cam 5, and the rocker arm 21 is supported by the top 37 of the rocker arm pivot 35 and the valve stem top of the exhaust cam 7. 8, the cam carrier on which the camshafts 41 and 43 are mounted is positioned so that the cams 42 and 44 can come into contact with the rollers 17 and 27 attached to the rocker arms 11 and 21. Attach to 1.

  Therefore, according to the present embodiment, the rocker arms 11 and 21 are dropped off with a very simple configuration in which the base ends 19a and 29a of the shaft-like members 19 and 29 are inserted into the lubricating oil supply holes 34 and 38 of the rocker arm pivots 31 and 35, respectively. Is prevented. Thereby, the rocking fulcrum portion 12 of the rocker arm 11 is overlapped with the top 33 of the rocker arm pivot 31 and the rocker arm 11 is supported by overlapping the rocking end portion 16 with the valve stem top portion 6, and at the top 37 of the rocker arm pivot 35. If the rocker arm 21 is supported with the rocking fulcrum 22 of the rocker arm 21 overlapped and the rocking end 26 overlapped with the valve stem top 8, the rocker arms 11 and 21 are prevented from falling off. In this state, the cam carrier to which the camshafts 41 and 43 are attached can be mounted on the cylinder head, and the assembly work efficiency of the engine is improved.

  In the above-described embodiment, the base ends 19a and 29a of the shaft-like members 19 and 29 serving as the locking means are inserted into the lubricating oil supply holes 34 and 38, and are locked and fixed. It is also possible to do.

(Second Embodiment)
A second embodiment of the rocker arm drop prevention mechanism according to the present invention will be described with reference to FIGS. 4 and 5, the same reference numerals are assigned to the portions corresponding to those in FIGS. 2 and 3, and the detailed description of the portions is omitted.

  FIG. 4 is an explanatory view of the valve operating mechanism on the intake port side corresponding to FIG. 2, and FIG. 5 is an explanatory view of the valve operating mechanism on the exhaust port side corresponding to FIG.

  As shown in FIG. 4A, the rocker arm pivot 31 has a substantially circular shape having a base portion 32 and a top portion 33 in which a convex spherical bearing surface 33a is formed by being inserted into a pivot mounting hole 9 formed in the cylinder head 1. It is formed in a columnar shape, and a lubricating oil supply hole 34 opens at the top 33.

  The rocking fulcrum portion 12 of the rocker arm 11 includes an annular supported surface 13 that can be slidably contacted with the bearing surface 33 a formed on the top portion 33 of the rocker arm pivot 31 and surrounds the lubricating oil supply hole 34, and the supported surface 13. It is formed in a substantially concave spherical shape having a recess 14 inside. A shaft member mounting hole 55 is formed in the central portion of the lubricating oil holding portion 14.

  The shaft-shaped member 56 has a shaft-like member 56 that serves as a locking means. The shaft-like member 56 has a base end 56a that is the other end inserted into the shaft-member mounting hole 55 and is fixed to the rocker arm 11, and a tip 56b that is one end. Is configured to be insertable with a gap in the lubricating oil supply hole 35 opened to the rocker arm pivot 31.

  In attaching the rocker arm 11, the base end 56 a of the shaft-like member 56 is inserted into the shaft member mounting hole 55 formed in the swing support portion 12 of the rocker arm 11, and the shaft-like member 56 is attached to the rocker arm 11.

  Further, as shown in FIG. 4 (b), the tip 56 b of the shaft-like member 56 protruding from the rocking fulcrum 12 of the rocker arm 11 is inserted from the opening of the lubricating oil supply hole 35 of the rocker arm pivot 31, and the supported surface 13. Is placed on the bearing surface 33a of the top surface 33, and the rocker arm 11 is set with the swing end portion 15 placed on the valve stem top portion 6 of the intake valve 5. The set rocker arm 11 is prevented from dropping by the shaft-like member 56 provided on the rocker arm 11 being locked in the lubricating oil supply hole 34 of the rocker arm pivot 31.

  Further, as shown in FIG. 5A, the rocker arm pivot 35 constituting the valve mechanism on the exhaust port 4 side is formed with a base portion 36 and a bearing surface 37a that are fitted into the pivot mounting holes 10 formed in the cylinder head 1. The lubricating oil supply hole 38 is opened in the top portion 37.

  The rocking fulcrum portion 22 of the rocker arm 21 includes an annular supported surface 23 that can be slidably contacted with the bearing surface 37 a formed on the top portion 37 of the rocker arm pivot 35 and surrounds the lubricating oil supply hole 38, and the supported surface 23. It is formed in a substantially concave spherical shape having a recess 24 inside. A shaft member mounting hole 57 is formed at the center of the recess 24.

  Further, it has a shaft-like member 58 serving as a locking means. The shaft-like member 58 is inserted into the shaft member mounting hole 57 and fixed to the rocker arm 21, and the lubricating oil supply hole 38 whose tip 58 b opens to the rocker arm pivot 35. It is formed so that it can be inserted with a gap. In attaching the rocker arm 21, the base end 58 a of the shaft-like member 58 is inserted into the shaft member mounting hole 57 formed in the swing support portion 22 of the rocker arm 21, and the shaft-like member 58 is attached to the rocker arm 21.

  Further, as shown in FIG. 5B, the tip 58b of the shaft-like member 58 protruding from the rocking fulcrum portion 22 of the rocker arm 21 is inserted into the lubricating oil supply hole 38 of the rocker arm pivot 35, and the supported surface 23 is moved to the rocker arm. The rocker arm 21 is set with the pivoting end portion 25 overlaid on the valve stem top portion 8 of the exhaust valve 7. The set rocker arm 12 is prevented from dropping by the shaft-like member 58 provided on the rocker arm 12 being locked in the lubricating oil supply hole 38 of the rocker arm pivot 35. With the rocker arms 11 and 21 set in this manner, the cam carrier to which the camshafts 41 and 43 are attached is mounted on the cylinder head 1.

  Therefore, according to the present embodiment, the rocker arm has a very simple structure in which the shaft-like members 56 and 58 attached to the rocker arms 11 and 21 are inserted into the lubricating oil supply holes 34 and 38 of the rocker arm pivots 31 and 35 and locked. The falling off of 11 and 21 is prevented. While the rocker arms 11 and 21 are held, the cam carrier to which the camshafts 41 and 43 are attached can be mounted on the cylinder head, and the efficiency of engine assembly work can be improved.

  In the above embodiment, the shaft-like members 56 and 58 are inserted into the shaft-member mounting holes 55 and 57 formed in the rocker arms 11 and 21 and fixed. However, the shaft-like members 56 and 58 are fixed to the rocker arms 11 and 21 in advance. They can be formed integrally or attached by welding or the like.

(Third embodiment)
A third embodiment of the rocker arm drop prevention mechanism according to the present invention will be described with reference to FIGS. 6 and 7, the same reference numerals are given to the portions corresponding to those in FIGS.

  As shown in FIG. 6A, the rocker arm pivot 31 constituting the valve operating mechanism on the intake port 3 side has a base 32 that can be inserted into a pivot mounting hole 9 formed in the cylinder head 1 and a concave spherical bearing. The surface 33 b is formed in a substantially cylindrical shape having a top 33 formed with a surface 33 b, and a lubricating oil supply hole 34 opens in the top 33.

  On the other hand, a valve adjusting screw 61 having a pivot 62 slidably contactable with the support surface 33 b of the rocker arm pivot 31 is attached to the swing support portion 12 of the rocker arm 11. A base end 63 a is coupled to the pivot 62, and a distal end 63 b, which is one end, has a gap in the lubricating oil supply hole 34 that opens on the bearing surface 33 b of the rocker arm pivot 31, and serves as a locking member that can be inserted into the shaft-like member 63. A proximal end 63a is provided.

  When the rocker arm 11 is attached, as shown in FIG. 6 (b), the tip 63 b of the shaft-like member 63 provided on the pivot 62 is inserted into the lubricating oil supply hole 34 opened at the top 33 b of the rocker arm pivot 31, and the pivot 62 The rocker arm 11 is supported with the swinging end portion 16 overlapped with the valve stem top portion 6 of the intake valve 5.

  In the rocker arm 11 which is set so as to span the top 33 of the rocker arm pivot 31 and the valve stem top 6 of the intake valve 5, the tip 63 b of the shaft-like member 63 provided on the pivot 62 is the lubricating oil of the rocker arm pivot 31. It is locked to the supply hole 34 to prevent the dropout.

  Further, as shown in FIG. 7A, the rocker arm pivot 35 constituting the valve mechanism on the exhaust port 4 side has a base portion 36 that can be inserted into a pivot mounting hole 10 formed in the cylinder head 1 and a concave spherical shape. The bearing surface 37 b is formed in a substantially cylindrical shape having a top portion 37, and a lubricating oil supply hole 38 is opened in the top portion 37.

  On the other hand, a valve adjusting screw 65 having a pivot 66 slidably contactable with the support surface 37 b of the rocker arm pivot 35 is attached to the rocking fulcrum 22 of the rocker arm 21. A shaft-like member 67 is provided as a locking means that can be inserted with a gap in a lubricating oil supply hole 38 that is coupled to the pivot 66 and has a tip 67b opening in the bearing surface 37b of the rocker arm pivot 35.

  When attaching the rocker arm 21, as shown in FIG. 7B, the tip 67 b of the shaft-like member 67 provided on the pivot 66 is inserted into the lubricating oil supply hole 38 that opens to the top 37 of the rocker arm pivot 35, and the pivot 66 Is placed on the bearing surface 37b, and the rocker arm 21 is set with the swinging end portion 26 placed on the valve stem top portion 7 of the exhaust valve 6. The set rocker arm 21 is prevented from falling off because the tip 67b of the shaft-like member 67 provided on the pivot 66 is engaged with the lubricating oil supply hole 38 of the rocker arm pivot 35.

  Thus, the rocker arm 11 is set so that the pivot 62 of the valve adjusting screw 61 overlaps the top 33 of the rocker arm pivot 31 and the swinging end 16 is bridged over the valve stem top 6 of the intake cam 5, and the rocker arm 21 is The pivot 66 of the valve adjusting screw 65 is placed on the top 37 of the rocker arm pivot 35, and the swinging end 26 is set over the valve stem top 8 of the exhaust cam 7.

  With the rocker arms 11 and 21 set in this way, the cam carrier to which the camshafts 41 and 43 are attached can come into contact with the rollers 17 and 27 attached to the rocker arms 11 and 21 by the cams 42 and 44. Position and mount on the cylinder head 1.

  Therefore, according to the present embodiment, the shaft-like member provided with the pivots 62 and 66 of the valve adjusting screws 61 and 65 in the lubricating oil suction holes 34 and 38 formed in the bearing surfaces 33b and 37b of the rocker arm pivots 31 and 35, respectively. With a simple configuration in which 63 and 67 are inserted, the set rocker arms 11 and 21 are prevented from falling off, and the efficiency of engine assembly work can be improved.

(Fourth embodiment)
A second embodiment of the rocker arm drop prevention mechanism according to the present invention will be described with reference to FIGS. In FIGS. 8 and 9, the same reference numerals are assigned to the portions corresponding to those in FIGS.

  FIG. 8 is an explanatory view of the valve operating mechanism on the intake port side corresponding to FIG. 2, and FIG. 9 is an explanatory view of the valve operating mechanism on the exhaust port side corresponding to FIG.

  As shown in FIG. 8A, the rocker arm pivot 31 on the intake port 3 side has a top portion 33 that is fitted into a pivot mounting hole 9 formed in the cylinder head 1 and has a base portion 32 and a bearing surface 33a. It is formed in a cylindrical shape, and a lubricating oil supply hole 34 opens at the top 33.

  The rocking support portion 12 of the rocker arm 11 includes an annular supported surface 13 that can be slidably contacted with the bearing surface 33 a formed on the top portion 33 of the rocker arm pivot 31 and surrounds the lubricating oil supply hole 34, and the supported surface 13. It is formed in a substantially concave spherical shape having a recess 14 inside.

  One or both of the top portion 33 of the rocker arm pivot 31 and the swing fulcrum portion 12 of the rocker arm 11 are magnetized, or a magnet is provided so that they can be attracted to each other.

  As a result, as shown in FIG. 8B, the supported surface 13 of the rocker arm 11 is superimposed on the bearing surface 33 a of the top portion 33 of the rocker arm pivot 31, and the swing end portion 15 is placed on the valve stem top portion 6 of the intake valve 5. Set to overlap. The rocking support portion 12 of the rocker arm 11 is attracted to the top portion 33 of the rocker arm pivot 31 to prevent the rocker arm 11 from falling off and is held at the intended support position.

  As shown in FIG. 9A, the rocker arm pivot 35 on the exhaust port 4 side has a top portion 37 that is fitted into a pivot mounting hole 10 formed in the cylinder head 1 and has a base portion 36 and a support surface 37a. It is formed in a cylindrical shape, and a lubricating oil supply hole 38 opens at the top 37.

  The rocking fulcrum portion 22 of the rocker arm 21 includes an annular supported surface 23 that can be slidably contacted with the bearing surface 37 a formed on the top portion 37 of the rocker arm pivot 35 and surrounds the lubricating oil supply hole 38, and the supported surface 23. It is formed in a concave shape having a concave portion 24 inside.

  One or both of the top portion 37 of the rocker arm pivot 35 and the rocking fulcrum portion 22 of the rocker arm 21 are magnetized or provided with magnets so that they can be attracted and coupled to each other.

  As a result, as shown in FIG. 9B, the supported surface 23 of the rocker arm 21 is overlapped with the bearing surface 37 a of the top portion 37 of the rocker arm pivot 35, and the swing end portion 25 is placed on the valve stem top portion 8 of the exhaust valve 7. It is supported repeatedly. The rocking support portion 22 of the rocker arm 21 is attracted to the top portion 37 of the rocker arm pivot 35 to prevent the rocker arm 21 from falling off. With the rocker arms 11 and 21 set in this manner, the cam carrier to which the camshafts 41 and 43 are attached is mounted on the cylinder head 1.

  Therefore, according to the present embodiment, one or both of the top portions 33 and 37 of the rocker arm pivots 31 and 35 or the rocking fulcrum portions 12 and 22 of the rocker arms 11 and 21 are magnetized, or a magnet is provided. The rocker arms 11 and 21 are prevented from falling off, and the efficiency of engine assembly work can be improved.

  In each of the above-described embodiments, the case where the rollers 17 and 27 are provided on the rocker arms 11 and 21 has been described as an example. However, instead of the rollers 17 and 17, a slipper portion that can be slidably contacted with the cam can be formed. .

DESCRIPTION OF SYMBOLS 1 Cylinder head 5 Intake valve 6 Valve stem top part 8 Valve stem top part 11 Rocker arm 12 Swing fulcrum part 14 Recess 16 Swing end part 19 Shaft-shaped member (locking means)
21 Rocker arm 22 Swing fulcrum 24 Recess 26 Swing end 29 Shaft-shaped member (locking means)
31 Rocker arm pivot 33 Top 33a Bearing surface 33b Bearing surface 34 Lubricating oil supply hole 35 Rocker arm pivot 37 Top 37a Bearing surface 38 Lubricating oil supply holes 42 and 44 Cam 55 Axial member mounting hole 56 Axial member (locking means)
57 Shaft-shaped member mounting hole 58 Shaft-shaped member (locking means 61 valve adjusting screw 62 pivot (tip)
63 Shaft-shaped member (locking means)
65 Valve adjustment screw 66 Pivot (tip)
67 Shaft-shaped member (locking means)

Claims (3)

In the rocker arm drop prevention mechanism in which the rocking fulcrum is supported on the top of the rocker arm pivot attached to the cylinder head of the engine,
The rocker arm pivot is provided with a lubricating oil supply hole opened at the top,
The rocking fulcrum is provided with a recess for forming a space in a portion facing the opening of the lubricating oil supply hole when the rocking fulcrum of the rocker arm is supported on the top of the rocker arm pivot. And a recessed portion that is further depressed in the center of the recess,
In the support state, one end is inserted into the lubricating oil supply hole from the opening, and the other end protrudes, and the locking is performed to stop the displacement of the swing fulcrum from the top in the one end insertion state. a manual stage,
The locking means is formed of a shaft-shaped member, the base end which is the one end is locked and fixed in the lubricating oil supply hole, and the tip which is the other end is a straight line having no protrusion on the peripheral surface. A rocker arm dropout prevention mechanism, wherein the rocker arm dropout prevention mechanism is inserted into the concave portion of the swing fulcrum . The rocker arm dropout prevention mechanism according to claim 1, wherein the shaft-shaped member has a cylindrical shape. In the rocker arm drop prevention mechanism in which the rocking fulcrum is supported on the top of the rocker arm pivot attached to the cylinder head of the engine,
The rocker arm pivot is provided with a lubricating oil supply hole opened at the top,
The rocker arm swinging fulcrum is supported on the top of the rocker arm pivot, and one end is inserted into the lubricating oil supply hole from the opening and the other end protrudes. A locking means for stopping the displacement of the swing fulcrum from the top,
The top of the rocker arm pivot has a concave spherical bearing surface in which the lubricating oil supply hole opens,
The swing fulcrum portion includes a valve adjustment screw that abuts on the support surface so that a tip is slidable,
The locking means is formed of a shaft-shaped member, the base end that is the other end is supported by the tip of the valve adjustment screw, and the tip that is the one end is a straight shape without a protrusion on the circumferential surface. A rocker arm dropout prevention mechanism, wherein the rocker arm dropout prevention mechanism is inserted into the lubricating oil supply hole formed in the support surface.

Images