Cam cap

Abstract

To provide a cam cap capable of smoothly taking out a jig.SOLUTION: A cam cap 16 includes: a cap body 40 including a bearing for supporting a cam shaft pressing a rocker arm 22 and mounted on a cylinder head 30; and a first boss 41 projecting from the cap body 40 in an axial direction of the cam shaft. In a state of mounting the cap body 40 on the cylinder head 30, the first boss 41 includes a part overlapping with the rocker arm 22 in the axial direction of the cam shaft. The first boss 41 has an inclined surface 45a continued to a first end portion 41c as an end portion of the first boss 41 in a direction projecting from the cap body 40 and positioned between the first end portion 41c and the rocker arm 22 in a direction toward the rocker arm 22 from the first end portion 41c. The inclined surface 45a is inclined so that a distance to the rocker arm 22 becomes longer toward a region near the first end portion 41c.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a cam cap. [Background technology]

[0002] The engine disclosed in Patent Document 1 includes a camshaft, a valve unit, a plurality of cam caps, and a cylinder head. The valve unit includes a plurality of valves, a plurality of lash adjusters, and a plurality of rocker arms. One end of the rocker arm is supported by the valve, and the other end of the rocker arm is supported by the lash adjuster. The rocker arm is pressed by the camshaft.

[0003] The plurality of cam caps are attached to the cylinder head. The plurality of cam caps are arranged at intervals in the axial direction of the camshaft. Each cam cap has a cap body and a boss. The cap body includes a bearing that supports the camshaft. The boss protrudes from the cap body in the axial direction of the camshaft. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-089513 A Summary of the Invention [Problem to be solved by the invention]

[0005] In engine assembly work, a jig is sometimes used to prevent the rocker arm from falling in the axial direction of the camshaft. The jig is inserted between two cam caps that are adjacent in the axial direction of the camshaft. This causes the rocker arm to be supported in a state where it is sandwiched between the jig and the lash adjuster. As a result, the rocker arm is less likely to fall in the axial direction of the camshaft.

[0006] When the cam cap is attached to the cylinder head, if the boss overlaps with the rocker arm in the axial direction of the camshaft, the jig is sandwiched between the boss and the rocker arm. Therefore, when removing the jig from between the cam caps, the jig is likely to get caught on the corners of the boss. Therefore, it is difficult to remove the jig smoothly. [Means for solving the problem]

[0007] A cam cap for solving the above problems includes a cap body that includes a bearing that supports a camshaft that presses a rocker arm, and is attached to a cylinder head, and a boss that protrudes from the cap body in the axial direction of the camshaft, and when the cap body is attached to the cylinder head, the boss includes a portion that overlaps with the rocker arm in the axial direction of the camshaft, and the boss has an inclined surface that is continuous with an end of the boss in a direction protruding from the cap body and is located between the end and the rocker arm in a direction from the end toward the rocker arm, and the inclined surface is inclined so that the distance between the rocker arm and the boss becomes longer the closer to the end.

[0008] According to the above configuration, when the jig is removed from between the boss and the rocker arm, the jig comes into contact with the inclined surface and gradually changes its posture to one that is easier to remove, so that the jig can be removed smoothly. [Brief description of the drawings]

[0009] [Figure 1] FIG. [Diagram 2] FIG. 2 is a plan view of the camshaft, the rocker arm, the cam cap, and the jig. [Diagram 3] 3 is a cross-sectional view of the camshaft, the rocker arm, the cam cap, and the jig taken along line 3-3 in FIGS. 1 and 2. FIG. [Figure 4]4 is a cross-sectional view of the camshaft, the rocker arm, the cam cap, and the jig taken along line 4-4 in FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, one embodiment of a cam cap will be described with reference to Figs. <Engine> First, an engine equipped with a cam cap will be described.

[0011] 1, the engine 10 includes an intake camshaft 11, an exhaust camshaft 12, an intake valve unit 13, an exhaust valve unit 14, an ignition coil 15, a plurality of cam caps 16, and a cylinder head 30. The intake camshaft 11, the exhaust camshaft 12, the intake valve unit 13, the exhaust valve unit 14, and a portion of the ignition coil 15 are housed inside the cylinder head 30. The plurality of cam caps 16 are attached to the cylinder head 30. The engine 10 of this embodiment is a V-type engine.

[0012] <Camshaft> 2, the intake camshaft 11 and the exhaust camshaft 12 each have a plurality of cams 17. The plurality of cams 17 are disposed at intervals in the axial direction of the camshafts 11, 12.

[0013] The intake camshaft 11 and the exhaust camshaft 12 are arranged in parallel. The direction in which the intake camshaft 11 and the exhaust camshaft 12 are aligned is defined as a first direction. The direction along the axial direction of the intake camshaft 11 and the exhaust camshaft 12 is defined as a second direction. The second direction is a direction perpendicular to the first direction. The direction perpendicular to both the first direction and the second direction is defined as a third direction.

[0014] When the engine 10 is mounted on a vehicle, the first direction is inclined with respect to the horizontal direction, the second direction extends in the horizontal direction, and the third direction is inclined with respect to the vertical direction.

[0015] <Valve unit> As shown in FIG. 1, the intake valve unit 13 and the exhaust valve unit 14 each have a plurality of valves 20, a plurality of lash adjusters 21, a plurality of rocker arms 22, and a support shaft 23.

[0016] Each valve 20 has a first end 20a and a second end 20b. The first end 20a and the second end 20b are axial ends of the valve 20. The second end 20b is an end of the valve 20 located opposite the first end 20a in the axial direction.

[0017] The multiple valves 20 are lined up in the second direction. The multiple lash adjusters 21 are lined up in the second direction. Each valve 20 and each lash adjuster 21 are lined up in the first direction.

[0018] The multiple rocker arms 22 are lined up in the second direction. Each rocker arm 22 extends in the first direction. Each rocker arm 22 has a valve support portion 22a and an adjuster support portion 22b. The valve support portion 22a is located at one end of the rocker arm 22 in the first direction. The adjuster support portion 22b is located at the other end of the rocker arm 22 in the first direction. The valve support portion 22a is supported by the second end portion 20b of the valve 20. The adjuster support portion 22b is supported by the lash adjuster 21.

[0019] The support shaft 23 is inserted into a portion between the valve support portion 22a and the adjuster support portion 22b of each rocker arm 22. The axial direction of the support shaft 23 extends in the second direction. The multiple rocker arms 22 are rotatably supported by the support shaft 23.

[0020] The intake valve unit 13 and the exhaust valve unit 14 are aligned in a first direction. The lash adjusters 21 of the intake valve unit 13 and the exhaust valve unit 14 are positioned inward of the valves 20 of the intake valve unit 13 and the exhaust valve unit 14 in the first direction.

[0021] The intake valve unit 13 and the intake camshaft 11 are aligned in the third direction. Each rocker arm 22 of the intake valve unit 13 is pressed by each cam 17 of the intake camshaft 11. The exhaust valve unit 14 and the exhaust camshaft 12 are aligned in the third direction. Each rocker arm 22 of the exhaust valve unit 14 is pressed by the cam 17 of the exhaust camshaft 12.

[0022] <Ignition coil> The ignition coil 15 has a coil portion 15a and an igniter portion 15b. The coil portion 15a extends from the igniter portion 15b. The igniter portion 15b has a bolt insertion hole 15h.

[0023] <Cylinder head> The cylinder head 30 has a head body 31 , a ladder frame 32 , and a head cover 33 .

[0024] <Head body> The head body 31 supports the intake valve unit 13 and the exhaust valve unit 14. The support structure of the head body 31 for the intake valve unit 13 and the exhaust valve unit 14 will be described in detail.

[0025] The head body 31 has an intake port 31a and an exhaust port 31b. The head body 31 has a first storage section 31c, a second storage section 31d, and a plurality of third storage sections 31e. The head body 31 has a first communication section 31f and a second communication section 31g. The first communication section 31f connects the intake port 31a to the first storage section 31c. The second communication section 31g connects the exhaust port 31b to the second storage section 31d.

[0026] The valve 20 of the intake valve unit 13 is inserted into the first communication portion 31f. A first end 20a of the valve 20 of the intake valve unit 13 protrudes into the intake port 31a. A second end 20b of the valve 20 of the intake valve unit 13 protrudes into the first housing portion 31c. The first housing portion 31c houses the rocker arm 22 and the support shaft 23.

[0027] The valve 20 of the exhaust valve unit 14 is inserted into the second communication portion 31g. A first end 20a of the valve 20 of the exhaust valve unit 14 protrudes into the exhaust port 31b. A second end 20b of the valve 20 of the exhaust valve unit 14 protrudes into the second housing portion 31d. The second housing portion 31d houses the rocker arm 22 and the support shaft 23.

[0028] The third housing portion 31e is located in a portion between the first housing portion 31c and the second housing portion 31d in the head body 31. The bottom surface of the third housing portion 31e has an adjuster housing hole 31h. The lash adjusters 21 of the intake valve unit 13 and the exhaust valve unit 14 are housed in the adjuster housing hole 31h. A portion of the lash adjuster 21 protrudes from the bottom surface of the third housing portion 31e.

[0029] <Ladder frame> The ladder frame 32 has a base frame 32a and a plurality of support parts 32b. The base frame 32a is connected to the head body 31. The plurality of support parts 32b are arranged at intervals in the second direction. Each support part 32b extends in the first direction. Each support part 32b has two first bearing components 32c. The two first bearing components 32c are arranged in the first direction.

[0030] <Head cover> The head cover 33 is connected to the base frame 32a. The base frame 32a is located between the head body 31 and the head cover 33. The head body 31, the base frame 32a, and the head cover 33 form the outer shell of the cylinder head 30. The head cover 33 has a first collar 33a and a second collar 33b. The first collar 33a protrudes from the inner surface and the outer surface of the head cover 33. The first collar 33a has a bolt insertion hole 33h. The bolt insertion hole 33h connects the inside and the outside of the cylinder head 30. The second collar 33b protrudes from the inner surface of the head cover 33. The second collar 33b has a bolt insertion hole (not shown). The bolt insertion hole connects the inside and the outside of the cylinder head 30.

[0031] <Cam cap> As shown in FIGS. 2 and 3, each cam cap 16 has a cap body 40, a first boss 41, a second boss 42, a first rib 43, and a second rib 44.

[0032] The cap body 40 is substantially rectangular. When viewed from above, the cap body 40 is rectangular. The cap body 40 has a first surface 40a and a second surface 40b. The first surface 40a and the second surface 40b are surfaces perpendicular to the thickness direction of the cap body 40. The second surface 40b is a surface located opposite to the first surface 40a in the thickness direction of the cap body 40.

[0033] The cap body 40 has four through holes 40h. Each through hole 40h penetrates the cap body 40 in the thickness direction. The four through holes 40h are aligned in the longitudinal direction of the cap body 40.

[0034] 1, the second surface 40b of the cap body 40 has two second bearing components 40c. The two second bearing components 40c are aligned in the longitudinal direction of the cap body 40. As shown in FIGS. 2 and 3, the first boss 41 protrudes from the cap body 40 in the short side direction of the cap body 40.

[0035] The first boss 41 is substantially cylindrical. The first boss 41 has a first surface 41a and a second surface 41b. The first surface 41a and the second surface 41b are surfaces perpendicular to the axial direction of the first boss 41. The second surface 41b is a surface located opposite the first surface 41a in the axial direction of the first boss 41. In the thickness direction of the cap body 40, the first surface 40a of the cap body 40 is located between the first surface 41a and the second surface 41b of the first boss 41. The first surface 41a of the first boss 41 has a first mounting hole 41h. The first mounting hole 41h is a female screw hole.

[0036] An end of the first boss 41 in a direction in which the first boss 41 protrudes from the cap body 40 is defined as a first end 41c. The direction in which the first boss 41 protrudes from the cap body 40 is a direction along the short side direction of the cap body 40. The first end 41c is a part of an outer circumferential surface 41d of the first boss 41.

[0037] The first boss 41 has an inclined portion 45 and a lightening portion 46. The inclined portion 45 and the lightening portion 46 are located at one of the axial ends of the first boss 41 that is closer to the second surface 41b. The inclined portion 45 is located in a portion of the first boss 41 close to the first end 41c. The inclined portion 45 has an inclined surface 45a. The inclined surface 45a connects the second surface 41b and the outer peripheral surface 41d. The inclined surface 45a is continuous with the first end 41c. The inclined surface 45a is inclined so as to approach the first surface 41a from the second surface 41b toward the first end 41c. The inclined surface 45a is a flat surface.

[0038] The hollowed-out portion 46 is located at a portion of the end portion close to the second surface 41b of the first boss 41 where the inclined portion 45 is not formed. The hollowed-out portion 46 is a portion that is recessed from the outer circumferential surface 41d of the first boss 41.

[0039] The first rib 43 and the second rib 44 each connect the first boss 41 to the cap body 40. In the longitudinal direction of the cap body 40, the first boss 41 is disposed between the first rib 43 and the second rib 44. The connection strength of the first boss 41 to the cap body 40 is reinforced by the first rib 43 and the second rib 44.

[0040] The second boss 42 protrudes from the cap body 40 in the short side direction of the cap body 40. The protruding direction of the first boss 41 from the cap body 40 and the protruding direction of the second boss 42 from the cap body 40 are opposite directions. In other words, the first boss 41 protrudes in one side of the short side direction of the cap body 40, whereas the second boss 42 protrudes in the other side of the short side direction of the cap body 40.

[0041] The second boss 42 is generally cylindrical. The axis of the second boss 42 overlaps with a side surface along the longitudinal direction of the cap body 40. Approximately half of the second boss 42 protrudes from the cap body 40, and the remaining half of the second boss 42 is located on the cap body 40.

[0042] The second boss 42 has a first surface 42a and a second surface 42b. The first surface 42a and the second surface 42b are surfaces perpendicular to the axial direction of the second boss 42. The second surface 42b is a surface located opposite to the first surface 42a in the axial direction of the second boss 42. In the thickness direction of the cap body 40, the first surface 40a of the cap body 40 is located between the first surface 42a and the second surface 42b of the second boss 42. The distance from the first surface 42a of the second boss 42 to the first surface 40a of the cap body 40 is longer than the distance from the first surface 41a of the first boss 41 to the first surface 40a of the cap body 40. The first surface 42a of the second boss 42 has a second mounting hole 42h. The second mounting hole 42h is a female screw hole.

[0043] The end of the second boss 42 in the direction in which the second boss 42 protrudes from the cap body 40 is defined as a second end 42c. The direction in which the second boss 42 protrudes from the cap body 40 is a direction along the short side direction of the cap body 40. The second end 42c is a part of the outer circumferential surface 42d of the second boss 42.

[0044] The second boss 42 has a recess 47. The recess 47 is a portion recessed toward the inner periphery side from the outer periphery 42d of the second boss 42. The recess 47 is located in a portion of the second boss 42 protruding from the cap body 40 in the short direction of the cap body 40. The recess 47 is provided over approximately half the circumference of the second boss 42. The recess 47 is provided in a part of the axial direction of the second boss 42. The recess 47 is not provided in the axial end of the second boss 42 that is close to the first surface 42a.

[0045] 1 and 3, each cam cap 16 is connected to the ladder frame 32 by a bolt B1 inserted into each through hole 40h and screwed into the support portion 32b. In other words, each cam cap 16 is attached to the cylinder head 30.

[0046] When each cam cap 16 is connected to the cylinder head 30, the longitudinal direction of each cap body 40 extends in a first direction. The lateral direction of the cap body 40 extends in a second direction. The thickness direction of the cap body 40 extends in a third direction. The first boss 41 and the second boss 42 protrude from the cap body 40 in the second direction. The first boss 41 protrudes in one direction in the second direction, and the second boss 42 protrudes in the other direction in the second direction.

[0047] The first bearing component 32c of the support portion 32b and the second bearing component 40c of the cap body 40 form a bearing 35. The cam cap 16 and the ladder frame 32 include the bearing 35. The camshafts 11, 12 are inserted through the bearing 35. The bearing 35 supports the portions of the camshafts 11, 12 where the cam 17 is not provided. The bearing 35 supports the camshafts 11, 12 rotatably.

[0048] 2, the multiple cam caps 16 are lined up at intervals in the second direction. The direction in which the first bosses 41 protrude from the cap body 40 is the same for all of the cam caps 16. The direction in which the second bosses 42 protrude from the cap body 40 is the same for all of the cam caps 16. Between the cap bodies 40 of two cam caps 16 adjacent to each other in the second direction, the second boss 42 of one cam cap 16 and the first boss 41 of the other cam cap 16 are located.

[0049] For two cam caps 16 adjacent to each other in the second direction, the distance from the second end 42c of one cam cap 16 to the first end 41c of the first boss 41 of the other cam cap 16 is defined as X1. For two cam caps 16 adjacent to each other in the second direction, the distance from the bottom surface of the recess 47 of one cam cap 16 to the first end 41c of the other cam cap 16 is defined as X2. Distance X2 is longer than distance X1 by the amount that recess 47 is recessed from the outer circumferential surface 42d of the second boss 42.

[0050] 2, the two cams 17 of the intake camshaft 11 and the two cams 17 of the exhaust camshaft 12 are located between two cam caps 16 adjacent to each other in the second direction. As described above, each cam 17 presses a rocker arm 22. Therefore, it can be said that the two rocker arms 22 of the intake valve unit 13 and the two rocker arms 22 of the exhaust valve unit 14 are located between two cam caps 16 adjacent to each other in the second direction.

[0051] Of the two rocker arms 22 in each of the intake valve unit 13 and the exhaust valve unit 14, the rocker arm 22 closer to the second boss 42 is referred to as a first rocker arm 221. Of the two rocker arms 22 in each of the intake valve unit 13 and the exhaust valve unit 14, the rocker arm 22 closer to the first boss 41 is referred to as a second rocker arm 222.

[0052] 2, the first boss 41 is located at the same position as the adjuster support portion 22b of the rocker arm 22 of the exhaust valve unit 14 in the first direction. A part of the first boss 41 is located at the same position as the second rocker arm 222 in the second direction. The second boss 42 is located between the rocker arm 22 of the intake valve unit 13 and the rocker arm 22 of the exhaust valve unit 14 in the first direction. The second boss 42 is located between the first boss 41 of the cam cap 16 having the second boss 42 and the first rocker arm 221 in the second direction.

[0053] As shown in FIG. 3, the first boss 41 includes a portion that overlaps with the second rocker arm 222 in the second direction. On the other hand, the second boss 42 does not include a portion that overlaps with the first rocker arm 221 in the second direction. Here, "the boss includes a portion that overlaps with the rocker arm in the second direction" refers to at least a part of the boss overlapping with at least a part of the rocker arm when viewed from the first direction. Therefore, the configuration in which "the boss includes a portion that overlaps with the rocker arm in the second direction" is not limited to a case where the boss and the rocker arm are in the same position in the first direction, but also includes a case where the boss and the rocker arm are in different positions in the first direction.

[0054] Specifically, when viewed from the first direction, a portion of the first boss 41 overlaps with a portion of the second rocker arm 222 of the exhaust valve unit 14. Therefore, the first boss 41 includes a portion that overlaps with the second rocker arm 222 of the exhaust valve unit 14 in the second direction. The second rocker arm 222 of the exhaust valve unit 14 is aligned with the second rocker arm 222 of the intake valve unit 13 in the first direction. Therefore, when viewed from the first direction, a portion of the first boss 41 also overlaps with a portion of the second rocker arm 222 of the intake valve unit 13. That is, the first boss 41 includes a portion that overlaps with the second rocker arm 222 of the intake valve unit 13 in the second direction.

[0055] 2, when viewed from the third direction, a part of the first boss 41 overlaps with the second rocker arm 222 of the exhaust valve unit 14 but does not overlap with the second rocker arm 222 of the intake valve unit 13. The second surface 41b of the first boss 41 faces the second rocker arm 222 of the exhaust valve unit 14.

[0056] 3, the inclined portion 45 is located between the first end 41c and the second rocker arm 222 in the third direction. In other words, the inclined portion 45 is located between the first end 41c and the second rocker arm 222 in the direction from the first end 41c toward the second rocker arm 222. The inclined surface 45a is inclined such that the distance between the inclined surface 45a and the second rocker arm 222 becomes longer as the inclined surface 45a is closer to the first end 41c.

[0057] As shown in FIG. 1, the ignition coil 15 is connected to the first boss 41 together with the head cover 33 by a bolt B2. The igniter portion 15b of the ignition coil 15 is disposed outside the cylinder head 30. The coil portion 15a extends into the cylinder head 30 through a coil insertion hole (not shown) formed in the head cover 33. The bolt insertion hole 15h of the igniter portion 15b communicates with the bolt insertion hole 33h of the first collar 33a. The bolt insertion hole 33h of the first collar 33a communicates with the first mounting hole 41h of the first boss 41. The bolt B2 inserted through the bolt insertion hole 15h of the igniter portion 15b and the bolt insertion hole 33h of the first collar 33a is screwed into the first mounting hole 41h of the first boss 41.

[0058] The head cover 33 is also connected to the cam cap 16 by a bolt B3. The bolt insertion hole of the second collar 33b communicates with the second mounting hole 42h of the second boss 42. The bolt B3 inserted into the bolt insertion hole of the second collar 33b is screwed into the second mounting hole 42h of the second boss 42. When the head cover 33 is connected to the cam cap 16, the cam cap 16 is located inside the head cover 33.

[0059] <Jig> In the assembly work of the engine 10, a jig 50 may be used to prevent the rocker arm 22 from falling in the axial direction of the camshafts 11, 12. The assembly work of the engine 10 is performed in a state in which the first direction and the second direction are perpendicular to the vertical direction, and the third direction is parallel to the vertical direction.

[0060] The jig 50 will now be described in detail. As shown in FIGS. 2 and 3, the jig 50 has a main body portion 51, a first pressing portion 52, and a second pressing portion 53.

[0061] The main body 51 has a rectangular parallelepiped shape. The main body 51 has a first side surface 51a and a second side surface 51b. The second side surface 51b is a surface located opposite to the first side surface 51a. The first pressing portion 52 protrudes from the first side surface 51a. The second pressing portion 53 protrudes from the second side surface 51b. The direction in which the first pressing portion 52 protrudes from the main body portion 51 is opposite to the direction in which the second pressing portion 53 protrudes from the main body portion 51. The first pressing portion 52 is provided on an upper portion of the first side surface 51a of the main body portion 51. The second pressing portion 53 is provided on an upper portion of the second side surface 51b of the main body portion 51.

[0062] The first pressing portion 52 has a first tip surface 52a. The first tip surface 52a is a surface located at the tip in the direction in which the second pressing portion 53 protrudes from the main body portion 51. The second pressing portion 53 has a second tip surface 53a. The second tip surface 53a is a surface located at the tip in the direction in which the second pressing portion 53 protrudes from the main body portion 51.

[0063] 2, the first pressing portion 52 has a relief portion 54. The relief portion 54 is a portion recessed from the first tip surface 52a. When the jig 50 is viewed in plan, the relief portion 54 has a substantially semicircular shape. The dimension from the bottom surface of the relief portion 54 to the second tip surface 53a is defined as Y. The dimension Y is longer than the distance X1 and shorter than the distance X2.

[0064] The operation of this embodiment will be described together with a method of using the jig 50. When the jig 50 is in use, the intake valve unit 13 and the exhaust valve unit 14 are housed in the head body 31 .

[0065] The worker lowers the jig 50 from between two adjacent support portions 32b in the second direction toward the rocker arms 22. The worker presses the four rocker arms 22 with the jig 50. The jig 50 is disposed so that the protruding directions of the first pressing portion 52 and the second pressing portion 53 from the main body portion 51 coincide with the second direction. The first pressing portion 52 presses the two first rocker arms 221. The second pressing portion 53 presses the two second rocker arms 222. The main body portion 51 is positioned between the two first rocker arms 221 and the two second rocker arms 222 in the second direction.

[0066] The adjuster support portion 22b of each first rocker arm 221 is supported in a state where it is sandwiched between the first pressing portion 52 and the lash adjuster 21. The adjuster support portion 22b of each second rocker arm 222 is supported in a state where it is sandwiched between the second pressing portion 53 and the lash adjuster 21. This makes it difficult for each rocker arm 22 to fall in the second direction. In this manner, the cam cap 16 is attached to the ladder frame 32 in a state where the adjuster support portions 22b of the first rocker arm 221 and the second rocker arm 222 are supported by the jig 50 so as not to fall easily. At this time, the bearings 35 rotatably support the intake camshaft 11 and the exhaust camshaft 12.

[0067] In a state where the cam cap 16 is attached to the ladder frame 32, the first pressing portion 52 is located near the second boss 42, and the second pressing portion 53 is located near the first boss 41 of the other cam cap 16. As described above, the first boss 41 overlaps with the second rocker arm 222 in the second direction. Therefore, the jig 50 that presses the second rocker arm 222 is sandwiched between the first boss 41 and the second rocker arm 222. In this embodiment, the second surface 41b of the first boss 41 faces the second rocker arm 222 of the exhaust valve unit 14. Therefore, the jig 50 is sandwiched between the first boss 41 and the second rocker arm 222 of the exhaust valve unit 14.

[0068] When the bearing 35 supports the intake camshaft 11, the rocker arm 22 of the intake valve unit 13 is supported in a state where it is sandwiched between the cam 17 of the intake camshaft 11 and the valve 20 and lash adjuster 21 of the intake valve unit 13. When the bearing 35 supports the exhaust camshaft 12, the rocker arm 22 of the exhaust valve unit 14 is supported in a state where it is sandwiched between the cam 17 of the exhaust camshaft 12 and the valve 20 and lash adjuster 21 of the exhaust valve unit 14. This prevents the rocker arm 22 from falling in the second direction even when the jig 50 is removed.

[0069] Next, a method for removing the jig 50 will be described. When removing the jig 50, the worker lifts the jig 50. In detail, the worker first passes the jig 50 between two cap bodies 40 adjacent to each other in the second direction. The worker then passes the jig 50 between the first boss 41 and the second boss 42.

[0070] At this time, as indicated by the two-dot chain line in FIG. 4, if the first boss 41 has a corner 410, the second pressing portion 53 is likely to get caught on the corner 410 of the first boss 41. In contrast, the first boss 41 of this embodiment has an inclined surface 45a. The inclined surface 45a is inclined such that the distance between the second rocker arm 222 and the inclined surface 45a increases as the surface approaches the first end 41c. Therefore, when the second pressing portion 53 comes into contact with the inclined surface 45a, the jig 50 gradually changes to a position that makes it easier to remove. Specifically, the jig 50 is inclined such that the first pressing portion 52 is positioned above the second pressing portion 53. Therefore, the worker can remove the jig 50 smoothly.

[0071] When passing the jig 50 between the first boss 41 and the second boss 42, the worker causes the second boss 42 to enter the relief portion 54. The dimension Y is shorter than the distance X2. Therefore, the jig 50 can pass between the first boss 41 and the second boss 42.

[0072] The worker then removes the jig 50 from between the first boss 41 and the second boss 42. The dimension Y is longer than the distance X1. For this reason, when the jig 50 is in a horizontal state, the jig 50 cannot be removed from between the first boss 41 and the second boss 42. Therefore, the worker removes the jig 50 from between the first boss 41 and the second boss 42 in a state in which the jig 50 is tilted so that the first pressing portion 52 is located above the second pressing portion 53.

[0073] Thereafter, the ignition coil 15 is attached to the first boss 41 of the cam cap 16 together with the head cover 33. The head cover 33 is attached to the second boss 42 of the cam cap 16.

[0074] The effects of this embodiment will be described. (1) The first boss 41 has an inclined surface 45a that is continuous with the first end 41c and is located between the first end 41c and the second rocker arm 222 in the direction from the first end 41c toward the second rocker arm 222. The inclined surface 45a is inclined such that the distance between the first end 41c and the second rocker arm 222 increases as the inclined surface 45a approaches the first end 41c. As a result, when the jig 50 is removed from between the first boss 41 and the second rocker arm 222, the jig 50 comes into contact with the inclined surface 45a and gradually changes to a position that makes it easier to remove. Therefore, the jig 50 can be removed smoothly.

[0075] The boss, end, and rocker arm described in the Means for Solving the Problem section correspond to the first boss 41, first end 41c, and second rocker arm 222 described in the Form for implementing the invention section, respectively.

[0076] This embodiment can be modified as follows: The embodiment and the modified examples can be combined with each other to the extent that there is no technical contradiction. The first boss 41 may be located at a position different from the second rocker arm 222 of the exhaust valve unit 14 in the first direction. In other words, the second surface 41b of the first boss 41 does not have to face the second rocker arm 222 of the exhaust valve unit 14. In this case, too, a part of the first boss 41 overlaps with the second rocker arm 222 of the exhaust valve unit 14 when viewed from the first direction. In other words, the first boss 41 includes a part that overlaps with the second rocker arm 222 of the exhaust valve unit 14 in the second direction. Even in such a case, depending on the shape of the jig 50, the jig 50 may be sandwiched between the first boss 41 and the second rocker arm 222.

[0077] For example, the first boss 41 is located between the second rocker arm 222 of the intake valve unit 13 and the second rocker arm 222 of the exhaust valve unit 14 in the first direction. In this case, if the jig 50 has the second pressing portion 53 extending in the first direction as in the above embodiment, the center of the second pressing portion 53 in the first direction is sandwiched between the first boss 41 and the second rocker arm 222. In this case, by providing the first boss 41 with an inclined surface 45a, the jig 50 can be smoothly removed.

[0078] The first boss 41 does not have to have the second surface 41b. In this case, the inclined portion 45 connects the outer circumferential surface 41d of the first boss 41 and the cap body 40. The inclined surface 45a is continuous with the first end portion 41c.

[0079] The first boss 41 does not have to have the hollowed-out portion 46 . The first boss 41 does not have to be a boss for attaching the ignition coil 15 to the cam cap 16. The first boss 41 may be a boss provided for another purpose.

[0080] The cam cap 16 does not have to have the second boss 42. [Explanation of symbols]

[0081] 10…Engine 11…Intake camshaft 12...Exhaust camshaft 13...Intake valve unit 14...Exhaust valve unit 15…Ignition coil 15a…Coil section 15b…Ignitor section 15h...Bolt insertion hole 16…Cam cap 17…Cam 20…Valve 20a...First end 20b…Second end 21...Lash adjuster 22…Rocka arm 22a…Valve support 22b…Adjuster support part 23...Support shaft 30…Cylinder head 31…Head body 31a…Intake port 31b…Exhaust port 31c…First storage section 31d…Second storage section 31e…Third storage section 31f…1st communication part 31g…Second communication part 31h…Adjuster accommodation hole 32…Ladder frame 32a…Base frame 32b...Support part 32c…First bearing component 33...Head cover 33a…First color 33b…Second color 33h...Bolt insertion hole 35…Bearing 40…Cap body 40a…Side 1 40b…Second side 40c...Second bearing component 40h…Through hole 41...First boss 41a…First page 41b…Second side 41c...first end 41d...Outer surface 41h…First mounting hole 42...Second boss 42a…First page 42b…Second side 42c…Second end 42d...Outer surface 42h…Second mounting hole 43…First rib 44…Second rib 45…Slope part 45a…Slanted surface 46…Meat cutout 47…Recess 50…Jig 51...Main body 51a...first side 51b…Second side 52...First pressing portion 52a...first tip surface 53...Second pressing part 53a…Second tip surface 54…Relief 221…First rocker arm 222…Second rocker arm 410…Corner B1…Bolt B2…Bolt B3…Bolt X1…distance X2…distance Y…Dimension

Claims

[Claim 1] a cap body that includes a bearing for supporting a camshaft that presses the rocker arm and is attached to a cylinder head; a boss protruding from the cap body in an axial direction of the camshaft; Equipped with the boss includes a portion that overlaps with the rocker arm in an axial direction of the camshaft when the cap body is attached to the cylinder head, the boss has an inclined surface that is continuous with an end of the boss in a direction protruding from the cap body and is located between the end and the rocker arm in a direction from the end toward the rocker arm, The inclined surface includes a portion that overlaps with the rocker arm in the axial direction of the camshaft, and is inclined so that the distance between the rocker arm and the inclined surface becomes longer as the portion approaches the end.

Images