JP5809587B2 - Engine cam chain chamber lubrication structure - Google Patents

Description

  The present invention relates to an engine cam chain chamber lubrication structure.

  As a conventional engine cam chain chamber, in Patent Document 1, a chain case part is integrally formed with an engine body at an end portion in a crankshaft direction of an engine body such as a cylinder block, and the chain case part is separated from the engine body. A body cover member is attached, and a cam chain chamber is defined by the chain case portion and the cover member. In Patent Document 1, a cover member separate from the cylinder block is referred to as a “chain case”. As another cam chain chamber, in Patent Document 2, the cam chain chamber is defined by a pair of case members formed separately from the engine body such as a cylinder block.

  The cam chain chamber houses cam chains, sprockets, gears and various rotating shaft ends for transmitting the rotational force of the crankshaft to the camshaft. In Patent Document 1, an oil passage formed in a wall of a cylinder block is opened in a cam chain chamber, and an orifice or the like is provided in the opening to inject oil into the cam chain chamber. Further, in Patent Document 2, an oil passage and an oil jet are provided in one case member coupled to the cylinder block among a pair of case members constituting the cam chain chamber, and oil is supplied from the oil jet to the cam chain and the like. It is comprised so that it may inject.

Japanese Patent Laid-Open No. 09-025810 Japanese Patent Application Laid-Open No. 07-63025

  In the former conventional example, it is necessary to drill a complicated oil passage for lubricating the cam chain chamber in the engine body made of a cylinder block or the like. In other words, the cylinder block has many places that obstruct the formation of the oil passage, such as a cooling water gallery and a fuel injection pump mounting hole, and when forming the oil passage avoiding these obstacles, the layout design of the oil passage There are so many restrictions.

  In the latter conventional example, the oil passage is formed in one case member that is a member different from the cylinder block, but the peripheral wall portion of the oil passage is formed so as to protrude into the cam chain chamber. Therefore, at the time of designing, the layout of the oil passage must be considered so as to avoid the interference between the cam chain and the peripheral wall portion of the oil passage, and the design restrictions on the layout of the oil passage increase.

  The present invention has fewer space limitations than a structure in which an oil passage for lubricating a cam chain chamber is formed in a cylinder block or the like in which a cooling water gallery or the like that obstructs the arrangement of the oil passage is formed, and An object of the present invention is to provide an engine cam chain chamber lubrication structure that can be easily drilled. Furthermore, by using the peripheral wall of the oil passage as a part of the reinforcing rib, it is possible to improve the rigidity of the chain case cover and to provide a cam chain chamber lubricating structure that can reduce vibration noise. Yes.

In order to solve the above problems, the present invention provides a chain case on the crankshaft direction end wall of an engine body that houses a crankshaft, and attaches the chain case cover to a cover mounting portion formed on the peripheral wall portion of the chain case. Therefore, in the engine cam chain chamber lubrication structure in which the chain case and the chain case cover form a cam chain chamber for storing the cam chain, the wall of the chain case cover communicates with an oil supply source. In addition, an oil passage having an oil supply portion that opens toward an oil supply location in the cam chain chamber is formed, and a passage forming wall portion that forms a peripheral wall of the oil passage protrudes outward of the cam chain chamber. It constitutes a rib, and solid ribs extending portion extending from the ribs set into the chain case cover Is, the rib and the rib extension, over the other end from the direction of one end perpendicular to the crankshaft direction of the chain case cover and across the chain case cover linearly.

  The present invention preferably includes the following configuration in the cam chain chamber lubrication structure of the engine.

(A) The rib and the rib extension portion of the oil passage extend from the upper end on the cylinder head side of the chain case cover to the lower end on the oil pan side.

(B) A screw type nozzle is screwed to the oil supply portion.

(C) The oil supply portion is formed so as to inject oil toward the meshing portion between the cam chain and the sprocket.

(D) The oil supply portion is formed so as to inject oil toward the bearing portion of the sprocket around which the cam chain is wound.

(E) The oil supply portion is formed so as to inject oil toward a meshing portion of a cam chain driving gear disposed in the cam chain chamber.

According to the present invention,
(1) Since the oil passage and the lubricating portion for lubricating the cam chain chamber are formed in the wall of the chain case cover formed separately from the cylinder block, etc., the structure for forming the oil passage in the cylinder block, etc. Compared to the above, there is less space limitation in the design of the oil passage, and drilling can be easily performed in a desired layout. In particular, even a narrow and long hole for an oil passage can be easily processed.

(2) Since the oil passage is formed in the chain case cover having a small weight and volume compared to a cylinder block having a large weight and volume, various drill holes facing various directions can be easily processed.

(3) The passage forming wall portion of the oil passage forms a rib protruding outward from the cam chain chamber, and the rib and the rib extension portion extended from the rib are perpendicular to the crankshaft direction of the chain case cover Since the chain case cover is linearly traversed from one end to the other end, the rigidity of the cam chain cover itself can be improved and vibration noise can be reduced.

(4) According to the configuration (a), since the rib and the rib extension portion extend from the upper end on the cylinder head side of the chain case cover to the lower end on the oil pan side, the rigidity of the entire chain case cover can be improved. it can.

(5) According to the configuration (b), since the screw type nozzle is screwed to the lubrication part, the nozzle can be easily attached and detached for maintenance or replacement.

(6) According to the configuration (c), since the lubrication part is directed to the meshing part of the cam chain and the sprocket, the lubrication action can improve the durability of the cam chain and the sprocket, and the meshing part The impact sound can be reduced.

(7) According to the configuration (d), since the lubrication part is directed to the bearing of the shaft part of the sprocket around which the cam chain is wound, the wear of the bearing part can be reduced and the durability can be improved. , Can keep the sprocket rotating smoothly.

(8) According to the configuration (e), since the lubricating portion is directed to the meshing portion of the cam chain driving gear, wear of each gear can be reduced and durability can be improved.

It is a front view of an engine provided with a cam chain chamber lubricating structure according to the present invention. It is a side view of the engine of FIG. FIG. 3 is a side view similar to FIG. 2 with the chain case cover removed. It is a side enlarged view of a chain case cover. It is a top view of the cam chain cover of FIG. It is a front enlarged view of the cam chain cover of FIG. It is a back surface enlarged view of the upper part of the cam chain cover of FIG.

  1 to 7 show an in-line multiple cylinder engine provided with a cam chain chamber lubricating structure according to the present invention, and an embodiment of the present invention will be described based on these drawings.

  In FIG. 1, the engine body 1 includes a lower crankcase member (main bearing case) 2, a cylinder block 3 integrally having an upper crankcase portion 3 a, and a cylinder head 5 in order from the lower side. They are fastened together by bolts. Further, a cylinder head cover ((valve arm cover) 6 is fastened to the upper surface of the cylinder head 5, and an oil pan 7 is fastened to the lower surface of the lower crankcase member 2. The lower crankcase member 2 and the upper crank A crankshaft (indicated by an axial center line) 10 is disposed substantially horizontally in the crank chamber constituted by the case portion 3a.

  A chain case 20 is integrally formed with the engine body 1 (the cylinder block 3 and the lower crankcase member 2) on one end side in the crankshaft direction of the engine body 1, and the end surface of the chain case 20 in the crankshaft direction is formed. A substantially flat chain case cover 21 is fastened by a plurality of bolts 23 to a cover mounting surface 20 a formed in the above. An intake manifold 11 is attached to the operation side (front side of the drawing) of the cylinder head 5.

  For convenience of explanation, the crankshaft direction is referred to as the “left-right direction” of the engine, the horizontal direction perpendicular to the crankshaft 10 is referred to as the “front-rear direction” of the engine, and the operation side on which the intake manifold 25 is disposed is defined. This will be described below as the “front side” of the engine.

  2 is a right side view of FIG. 1, and FIG. 3 is a right side view of the chain case cover 21 removed. In FIG. 3, the chain case 20 is formed over substantially the entire end surface in the crankshaft direction of the engine body 1 except for the arrangement space of the cooling water pump 22, and in the cam chain chamber 32 surrounded by the chain case 20. Are disposed at one end of the crankshaft 10, a power take-out gear 33, an intermediate gear 34 disposed above the power take-out gear 33 and meshing with the power take-out gear 33, and a front upper portion of the intermediate gear 34. A cam drive gear 35 that meshes with the intermediate gear 34, a pump drive gear 36 that is arranged in front of the power take-out gear 33 and meshes with the power take-out gear 33, and the like. The diameter and the number of teeth of the cam drive 35 gear are twice that of the cam drive force take-out gear 33. In other words, the rotation of the crankshaft 10 is reduced to ½ and transmitted to the cam drive gear 35. The suction part of the cooling water pump 22 communicates with the temperature control valve case 24.

  A cam drive sprocket 37 is disposed on the same axis as the cam drive gear 35 and so as to rotate integrally with the cam drive gear 35. The cam drive gear 35 and the cam drive sprocket 37 have a common bearing portion ( The cam drive shaft 40 is rotatably supported via a boss portion 41. A cam chain 44 is wound around the cam drive sprocket 37. The cam chain 44 extends rearward and upward from the cam drive sprocket 37, passes through a chain tunnel formed in the cylinder head 5, and drives the intake and exhaust valves. The cam shaft 46 is wound around a cam driven sprocket 47. A chain tensioner 50, a chain guide 51, and the like are arranged on the moving path of the cam chain 44.

  An oil pump 25 is disposed in the lower crankcase member 2, and the pump drive gear 25 a is fixed to a pump drive shaft 25 a of the oil pump 25. The discharge part of the oil pump 25 needs to be lubricated in the engine body 1 through an oil passage 26 formed in the wall of the cylinder block 3 (including the lower crankcase part 3a) and the lubricating oil main gallery 26a, 26b. It communicates with a location, and communicates with a cover lubrication port 30 formed at the front upper end of the chain case 20 via an oil passage 27 formed at the upper end of the cylinder block 3.

  The cover mounting surface (cover mounting portion) 20a of the chain case 20 is formed in the same vertical plane, and a plurality of fastening female screw holes 20b are formed at intervals from each other. As shown in FIG. 2, the chain case cover 21 is fastened by bolts 23.

  FIG. 4 is an enlarged side view of the chain case cover 21. In the wall of the chain case cover 21, a first oil passage 61 linearly extending from the front upper end of the chain case cover 21 to the rear lower side and a chain is shown. Front and rear second and third oil passages 62, 63 are formed extending linearly from the upper end of the case cover 21 substantially vertically downward, and the vertical second and third oil passages 62, 63 are formed. Are arranged at intervals in the front-rear direction, and the lateral first oil passage 61 intersects the second and third oil passages 62 and 63 on the way to the second and third oil passages 62 and 63. Communicate.

  The lateral first oil passage 61 is formed by drilling a hole from the front upper end of the chain case cover 21, and the front end opening of the first oil passage 61 is closed by a screw-type plug 64. The vertically oriented second and third oil passages 62, 63 are drilled from the upper end of the chain case cover 21, and the upper end openings of the second and third oil passages 62, 63 are screwed. The plugs 65 and 66 are closed.

  An oil inlet 67 that opens toward the cylinder block is formed in the vicinity of the front end of the first oil passage 61, and a first opening that opens into the cam chain chamber 32 is formed at the rear of the first oil passage 61. 1 oil supply portion 71 is formed. Second and third oil supply portions 72 and 73 that open toward the inside of the cam chain chamber 32 are formed at the lower ends of the vertical second and third oil passages 62 and 63.

  FIG. 5 is an enlarged plan view of the chain case cover 21. In FIG. 5, passage forming wall portions 61a, 62a, which form passage outer peripheral walls of the first, second and third oil passages 61, 62, 63, 63a is formed so as to protrude outward from the cam chain chamber 32 from the outer surface opposite to the chain case 20 side. That is, each of the passage forming wall portions 61a, 62a, 63a serves as a rib formed on the outer surface of the chain case cover 21, and hereinafter, each of the passage forming wall portions 61a, 62a, 63a is referred to as the first. , Referred to as second and third ribs.

  In FIG. 4, a straight line extends from the lower end of each of the ribs 62 a, 63 a on the downward extension line of the second and third ribs 62 a, 63 a constituting the outer peripheral walls of the vertically oriented second and third oil passages 62, 63. Rib extensions 62c and 63c extending downward in a shape are formed. The rear third rib extension 63c reaches the lowermost edge of the chain case cover 21, and the front second rib extension 62c extends from the front upper end of the chain case cover 21 to the lower end. It reaches the middle part of the edge. In other words, the third rib 63a and the third rib extension portion 63c vertically cut the chain case cover 21 from the uppermost end to the lowermost end in a straight line, and the second rib 62a and the second rib extension portion. 62 c cuts the chain case cover 21 linearly from the uppermost end to the peripheral end of the lower chain case cover 21. In addition, a short first rib extension portion 61c extending linearly rearward from the end of the first rib 61a is formed on the rear extension line of the first rib 61a, and the first rib 61a and the first rib 61a One rib extension 61c crosses the vicinity of the upper end of the chain case cover 21 from substantially the front end to the vicinity of the rear end.

  FIG. 6 is an enlarged front view of the upper portion of the chain case cover 21. In FIG. 6, the first and second lubrication portions 71 and 72 are provided with screw-type first and second lubrication in the form of hexagonal columns. Nozzles 81 and 82 are screwed, respectively. The first oil nozzle 81 screwed to the first oil supply portion 71 includes an oil passage 81a extending in the nozzle length direction and a tip portion of the oil passage 81a. A thin nozzle 81b that extends radially outward and opens at the outer end is formed. On the other hand, the second oil supply nozzle 82 screwed to the second oil supply portion 72 has an oil passage 82a extending in the nozzle length direction and an opening formed in the tip portion of the oil passage 82a in the nozzle length direction. A narrow nozzle hole 82b is formed.

  FIG. 7 is a rear view of the upper part of the chain case cover 21, and the first and second oiling nozzles 81 and 82 screwed to the first and second oiling parts 71 and 72 are hexagonal, The structure in which three nozzle holes 81b of the first oil supply nozzle 81 are formed is clarified.

  The position of the first oil supply nozzle 81 is the position A1 in FIG. 3, and oil can be injected in the vicinity of the meshing start end of the cam chain 44 and the cam drive sprocket 37. The second oil supply nozzle 82 in FIG. The position A2 is a position A2 substantially corresponding to the cam drive shaft 40 in FIG.

  Further, the third oil lubrication part 73 in FIG. 7 has a structure in which oil is directly supplied to the cam chain chamber 32 through a throttle formed in the chain case cover 21, and the intermediate gear 34 and the cam drive gear 35 in FIG. It is position A3 corresponding to the meshing part.

(Function)
In FIG. 3, the oil sucked from the oil pan 7 by the rotation of the oil pump 25 is sent from the oil passage 26, the oil main gallery 26a, 26b, etc. to various oil supply points of the engine through various oil devices and oil passages. It is done. A part of the oil passes through an oil passage 27 formed at the upper end portion of the cylinder block 3 and an upper end oil supply port 30 of the chain case 20, and then from the oil inlet 67 of the chain case cover 21 shown in FIG. 61 is supplied to the front end portion.

  The oil pumped backward through the first oil passage 61 branches to the second oil passage 62 on the way, reaches the lower end of the second oil passage 62, passes through the second oil supply section 72, and passes through the second oil passage 72 in FIG. The oil is injected from the second oil supply nozzle 82 to the drive shaft 40 and the bearing 41 (position A2) in FIG.

  A part of the oil that has flowed to the rear portion of the first oil passage 61 in FIG. 4 passes through the first oil supply portion 71 and then passes through the first oil supply nozzle 81 in FIG. 6 and the cam chain 44 and the cam drive sprocket in FIG. 37 is injected toward the meshing start end (position A1).

  The oil that has reached the rear end of the first oil passage 61 in FIG. 4 flows into the third oil passage 63, flows to the lower end in the third oil passage 63, passes through the third oil supply portion 73, It is injected toward the gear meshing portion (position A3) in FIG.

[Effects of the embodiment]
(1) Since the oil passages 61, 62, 63 and the lubricating portions 71, 72, 73 for lubricating the cam chain chamber are formed in the wall of the chain case cover 21 formed separately from the engine body 1. Compared with the structure in which the oil passage for oil supply to the cam chain chamber is formed on the engine main body side, when designing the oil passages 61, 62, 63, the degree of layout is increased and the drilling can be easily performed. In particular, even a narrow and long hole for an oil passage can be easily processed.

(2) Since the oil passages 61, 62, 63 are formed in the chain case cover 21 having a small weight and volume, drilling in various directions is easy.

(3) Since the passage forming wall portions of the oil passages 61, 62, 63 constitute ribs 61a, 62a, 63a protruding outward from the cam chain chamber, the rigidity of the cam chain cover 21 can be improved.

(4) Regarding the second and third ribs 62a, 63a, the ribs 62a, 63a and the rib extensions 62c, 63c extending from the ribs 62a, 63a extend from the upper end to the lower end of the chain case cover 21, Since the chain case cover 21 is cut in a straight line, the rigidity of the cam chain cover 21 can be further improved, thereby reducing vibration noise.

(5) Since the screw-type first and second oil supply nozzles 81 and 82 are screwed to the first and second oil supply parts 71 and 72, the oil supply nozzles can be easily used for maintenance or replacement. 81 and 82 can be attached and detached.

(6) The first lubrication nozzle 81 of the first lubrication section 71 lubricates the meshing start end (position A1) between the cam chain 44 and the cam drive sprocket 37, so that the durability of the cam chain 44 and the cam drive sprocket 37 is improved. Performance can be improved, and impact noise at the meshing portion (position A1) can be reduced.

(7) The second lubrication nozzle 82 of the second lubrication section 72 lubricates the drive shaft 40 and the bearing section 41 of the cam drive sprocket 37 around which the cam chain 44 is wound. Wear can be reduced, durability can be improved, and smooth rotation of the cam drive sprocket 37 can be maintained.

(8) Since the third oil-lubricating portion 73 faces the meshing portion (position A3) of the cam chain driving gears 33 and 34, wear of the gears 33 and 34 can be reduced and durability can be improved. it can.

[Other embodiments]
(1) In the said embodiment, although the lubrication part 71,72,73 is provided in three places, the number of lubrication parts is increased / decreased suitably as needed.

(2) In the above embodiment, the chain case is integrally formed with the engine body such as a cylinder block, but a structure formed separately is also included in the present invention.

(3) Various modifications and changes can be made without departing from the spirit and scope of the present invention described in the claims.

1 Engine body 2 Lower crankcase member (main bearing case)
3 Cylinder Block 3a Upper Crank Case 5 Cylinder Head 10 Crank Shaft 20 Chain Case 21 Chain Case Cover 25 Oil Pump 33 Cam Drive Power Extraction Gear 34 Intermediate Gear 35 Cam Drive Gear 37 Cam Drive Sprocket 41 Cam Drive Shaft 44 Cam Chain 46 Cam shaft 61, 62, 63 Oil passage 61a, 62a, 63a Rib 61c, 62c, 63c Rib extension 67 Oil inlet 71, 72, 73 Oiling part 81, 82 Screw type oiling nozzle

Claims (6)

A chain case is provided on the crankshaft end wall of the engine body that houses the crankshaft.
An engine cam chain chamber in which a cam chain chamber for accommodating a cam chain is formed by the chain case and the chain case cover by attaching a chain case cover to a cover mounting portion formed on a peripheral wall portion of the chain case In the lubrication structure,
In the wall of the chain case cover, there is formed an oil passage having an oil supply portion communicating with an oil supply source and opening toward an oil supply location in the cam chain chamber,
The passage forming wall portion forming the peripheral wall of the oil passage constitutes a rib protruding outward of the cam chain chamber ,
The chain case cover is provided with a solid rib extension extending from the rib ,
Said rib and said rib extensions, the chain case cover over the other end from the direction of one end perpendicular to the crankshaft direction, linearly and across the chain case cover, a cam chain chamber of the engine, characterized in that Lubrication structure.
2. The cam chain chamber lubrication structure for an engine according to claim 1, wherein the rib and the rib extension portion of the oil passage extend from an upper end on the cylinder head side of the chain case cover to a lower end on the oil pan side.
The cam chain chamber oil supply structure of the engine according to claim 1 or 2, wherein a screw type nozzle is screwed into the oil supply portion.
4. The cam chain chamber oil supply structure for an engine according to claim 1, wherein the oil supply portion is formed so as to supply oil toward a meshing portion between the cam chain and the sprocket. 5.
4. The engine cam chain chamber oil supply according to claim 1, wherein the oil supply portion is formed so as to supply oil toward a bearing portion of a sprocket around which the cam chain is wound. 5. Construction.
  The engine according to any one of claims 1 to 5, wherein the oil supply portion is formed to inject oil toward a meshing portion of a cam chain driving gear disposed in the cam chain chamber. Cam chain chamber lubrication structure.

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