JP2002339723A - Passage structure of cylinder block - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maximize passage cross sections of a bleeder passage and a lubricating oil returning passage that are formed in a side wall of a cylinder head. SOLUTION: The end of the bleeder passage 45 formed in the side wall 11f of the cylinder block 11 having an integral crankcase is opened in the bottom surface of a connecting part between the side wall 11f of the cylinder block 11 and the journal support wall 11h. The opening part of the bleeder passage 45 has a first part 45a extending along the side wall 11f of the cylinder block 11 and a second part 45b extending into the journal support wall 11h orthogonally to the first part 45a, and is formed in a T-shape. A passage partition 56 for partitioning both ends of the first part 45a extends in the direction from the side wall 11f of the cylinder block 11 to the journal support wall 11h so as to be along a moving track of a weight part 19b of a crankshaft 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder in which the end of a passage formed in the side wall of a cylinder block integrally provided with a crankcase is opened at the bottom of the connection between the side wall of the cylinder block and the journal support wall. The present invention relates to a block passage structure.

[0002]

2. Description of the Related Art An engine provided with a breather device on the side of a cylinder block has a breather passage formed in a side wall of the cylinder block for connecting an internal space of a crankcase to a breather chamber.
No. 37 discloses this. In this apparatus, the lower end of the breather passage is opened at a connection portion between the side wall of the cylinder block and the journal support wall in order to secure the passage cross-sectional area of the breather passage without increasing the thickness of the side wall of the cylinder block. .

[0003]

Since the weight of the crankshaft is located in the space defined by the pair of adjacent journal support walls and the side wall of the cylinder block, the width of the breather passage of the cylinder block is reduced. If the crankshaft is expanded in the axial direction without any difficulty, there is a problem that a passage partition that partitions the breather passage interferes with a weight portion of the crankshaft. Patent No. 26858 mentioned above
In the device described in Japanese Patent Publication No. 37, since the passage partition of the breather passage extends obliquely from the side wall of the cylinder block toward the journal support wall, a wasteful space is provided between the passage partition and the weight portion of the crankshaft. It is hard to say that the breather passage maximizes the passage cross-sectional area.

[0004] Such a problem similarly occurs when a lubricating oil return passage for returning lubricating oil from the cylinder head to the crankcase is formed on the side wall of the cylinder block.

The present invention has been made in view of the above circumstances, and has as its object to maximize the cross-sectional area of a breather passage and a lubricating oil return passage formed in a side wall of a cylinder head.

[0006]

According to the first aspect of the present invention, an end of a passage formed in a side wall of a cylinder block integrally provided with a crankcase is provided. In a passage structure of a cylinder block which is opened at a bottom surface of a connection portion between a side wall of a cylinder block and a journal support wall, an opening of the passage has a first portion extending in a direction along a side wall of the cylinder block and a first portion orthogonal to the first portion. And a second portion extending inside the journal support wall, and is formed in a T-shape, and a passage partition partitioning both ends of the first portion is formed so as to follow a movement locus of a weight portion of a crankshaft. In addition, a passage structure of a cylinder block is proposed which extends from a side wall of the cylinder block in a direction along a journal supporting wall.

According to the above construction, the passage opening to the bottom surface of the connecting portion between the side wall of the cylinder block and the journal support wall has the first portion and the second portion which are orthogonal to each other, and has a T shape.
A passage partition, which is formed in the shape of a letter, and defines both ends of a first portion extending in a direction along the side wall of the cylinder block of the passage, a journal is formed from the side wall of the cylinder block along the movement locus of the weight portion of the crankshaft. Extends in the direction along the support wall, maximizing the cross-sectional area of the passage while avoiding the passage partition interfering with the weight of the crankshaft and without making the cylinder block partition thicker or bulging. Can be secured.

According to the invention described in claim 2,
In a cylinder block passage structure in which an end of a passage formed on a side wall of a cylinder block integrally provided with a crankcase is opened on a bottom surface of a connection portion between a side wall of the cylinder block and a journal support wall, an opening of the passage is provided. Is formed in a T-shape having a first portion extending in a direction along the side wall of the cylinder block and a second portion orthogonal to the first portion and extending inside the journal support wall. A passage partition wall defining both ends of the portion extends in a direction orthogonal to a side wall of the cylinder block at a position facing the weight portion of the crankshaft, and is then connected to a journal support wall. Suggested.

According to the above construction, the passage opening on the bottom surface of the connecting portion between the side wall of the cylinder block and the journal supporting wall has the first portion and the second portion which are orthogonal to each other.
A passage partition, which is formed in the shape of a letter, and defines both ends of a first portion extending in a direction along the side wall of the cylinder block of the passage, a direction orthogonal to the side wall of the cylinder block at a position facing the weight portion of the crankshaft. After being extended to the journal support wall, the space at the position facing the weight portion of the crankshaft can be effectively utilized, and the cross-sectional area of the passage can be maximized.

According to the third aspect of the present invention,
In addition to the configuration of claim 1 or claim 2, in the passage block partitioning the passage, the passage partition and the side wall of the cylinder block are bridged and reinforced by a connecting portion and reinforced. A passage structure is proposed.

[0011] According to the above configuration, since the passage partition that divides the passage is bridged and reinforced by the connecting portion, a decrease in the rigidity of the cylinder block due to the formation of the passage can be minimized.

According to the invention described in claim 4,
In addition to the configuration of the third aspect, a passage structure of a cylinder block is proposed, wherein the connection portion is formed between a plurality of through holes penetrating a bottom wall that closes the passage.

According to the above configuration, since the connecting portion is formed between the plurality of through holes penetrating the bottom wall closing the passage, the connecting portion can be formed by a simple process for forming the through hole in the bottom wall. it can.

The breather passage 45 of the embodiment corresponds to the passage of the present invention, and the breather passage partition 56 of the embodiment corresponds to the passage partition of the present invention.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 8 show a first embodiment of the present invention. FIG. 1 is a longitudinal sectional view of the engine (a sectional view taken along line 1-1 in FIG. 2, and FIG. 2 is a sectional view taken along line 2-2 in FIG. 1). 3 is a view in the direction of arrow 3 in FIG. 1, FIG. 4 is a view in the direction of arrow 4-4 in FIG. 2, and FIG.
6 is a sectional view taken along line 6-6 of FIG. 2, FIG. 7 is a view taken along line 7-7 of FIG. 3, and FIG. 8 is an enlarged view of a portion 8 of FIG.

As shown in FIG. 1, an in-line four-cylinder engine E for an automobile includes a cylinder block 11, a cylinder head 12 connected to an upper surface of the cylinder block 11, and a head cover 13 connected to an upper surface of the cylinder head 12.
And an oil pan 14 coupled to the lower surface of the cylinder block 11. Four cylinder sleeves 16 are embedded in the upper part of the cylinder block 11 in which the crankcase 15 is integrally formed in the lower part. Pistons 17 slidably fitted to these cylinder sleeves 16 are connected rods 18. Are connected to the crankshaft 19 via. The combustion chamber 20 is attached to the cylinder head 12.
An intake port 21 and an exhaust port 22 communicating with each other.
Are formed, and the intake valve holes and the exhaust valve holes are opened and closed by intake valves 23 and exhaust valves 24, respectively.

An intake camshaft 26 having an intake cam 25 on the cylinder head 12 and an intake rocker arm 28 supported via an intake rocker arm shaft 27
Are provided, and the intake valves 23 are driven by intake rocker arms 28 that swing by intake cams 25 that rotate in conjunction with the crankshaft 19. The cylinder head 12 is provided with an exhaust camshaft 30 having an exhaust cam 29 and an exhaust rocker arm 32 supported via an exhaust rocker arm shaft 31, and rotates in conjunction with the crankshaft 19. The exhaust valves 24 are driven by the exhaust rocker arms 32 that swing by the exhaust cams 29 that are activated.

A breather device 33 is provided on a side surface on the intake side of the cylinder block 11, and a starter device 34 of the engine E is disposed outside the breather device 33.

2 to 6, the breather device 33 is detachably attached to the substantially pentagonal coupling surface 11a formed on the intake side of the cylinder block 11 with five bolts 41. Cover plate 4 fixed to
2, and a breather chamber 43 is defined between the cover plate 42 and the cylinder block 11. Inside the coupling surface 11a, two ribs 11b and 11c extending linearly and one rib 11d and 11d extending in a V shape are formed.
11e, and these ribs 11b, 11b
The c, 11d, and 11e abut on the inner surface of the cover plate 42 to form a zigzag labyrinth in the breather chamber 43 and a narrow groove 44 connected to an intermediate portion of the labyrinth.

The lower end of the labyrinth of the breather chamber 43 communicates with the internal space of the crankcase 15 through a breather passage 45 formed in the side wall 11f of the cylinder block 11, and the upper end of the labyrinth is connected to a joint 46 fixed to the cover plate 42. It is connected to the intake system of the engine E via a breather hose 47 and a PCV valve (not shown). The upper end of the narrow groove 44 connected to the middle part of the labyrinth communicates with the internal space of the cylinder head 12 through a through hole 11g and a breather passage 48 formed in the side wall 11f of the cylinder block 11.

The cover plate 42 is formed by pressing a metal plate, and has a flange 42a whose outer peripheral portion is bent toward the cylinder block 11, a S-shaped convex portion 42b, 42c which expands in a direction away from the cylinder block 11. 4
2d and two concave portions 42 depressed toward the cylinder block 11 side
e, 42f are formed. In order to increase the volume of the breather chamber 43, the protrusions 42b, 4
2c and 42d are arranged corresponding to the zigzag labyrinth of the breather chamber 43. One recess 42e is arranged along the upper inner surface of the coupling surface 11a, and the other recess 42f fits shallowly in the groove 44 connected to the breather passage 48 (see FIG. 5). When the cover plate 42 is fixed to the cylinder block 11, liquid packing is applied to the coupling surface 11a and the ribs 11b, 11c, 11d, 11e of the cylinder block 11, but the concave portion 42f of the cover plate 42 is formed by the coupling surface 11a and the rib 11e. The liquid packing can be prevented from flowing into the groove 44 and closing the groove 44 by fitting into the groove 44 interposed between the grooves 44.

A starter device 34 disposed outside the breather device 33 is provided with a starter motor 49 having a planetary gear type speed reducer and a fly-out type pinion, the tip of which is fitted inside the transmission T, and a starter motor 49 attached thereto. And a starter motor 49.
The electromagnetic switch 50 and the electromagnetic switch 50 are both formed in a substantially cylindrical shape, and are integrated adjacently in parallel. Starter device 34
Is a mounting flange 49a formed on the starter motor 49.
Are fixed to the overhang portion 52 of the transmission T with two bolts 51, 51 penetrating the transmission T (see FIG. 6).

The starter device 34 includes two bolts 5 inserted from the projecting portion 52 of the transmission T.
The mounting flanges 49a formed on the starter motor 49 may be fixed at the positions 1 and 51. In this case, the bolts 51 and 51 can be provided regardless of the shape of the starter device 34. And workability is improved.

As is apparent from FIG. 6, the central convex portion 42c of the convex portions 42b, 42c and 42d of the cover plate 42 is formed between the starter motor 49 of the starter device 34 and the electromagnetic switch 50 to form a cylinder block. 1
It protrudes into the recess 53 facing the one side wall 11f.
Thereby, the starter device 34 is connected to the cylinder block 11.
The projection 42c of the cover plate 42 can be made to protrude greatly without increasing the size of the entire engine E by arranging the breather chamber 43 at a position away from the engine E to maximize the volume of the breather chamber 43.

As is apparent from FIGS. 6 to 8, the opposing side walls 1 of the crankcase 15 of the cylinder block 11
1f, 11f are connected by five journal support walls 11h..., And these journal support walls 11h.
Five journals 19a of the crankshaft 19 are rotatably supported between bearing caps 55 fixed to bolts 54 on the lower surface of the journals. Three through holes 11j, 11 formed in the bottom wall 11i of the breather chamber 43
The breather chamber 43 and the upper end of the breather passage 45 communicate with each other via k and 11k. And breather passage 45
The upper end of the cylinder block 11 is bridged and reinforced by two connecting portions 11m, 11m formed between the three through holes 11j, 11k, 11k, and the rigidity of the cylinder block 11 due to the formation of the breather passage 45 is minimized. Can be suppressed. Moreover, since the connecting portions 11m, 11m are formed only by processing the three through holes 11j, 11k, 11k in the bottom wall 11i of the breather chamber 43, the processing is extremely easy. Further, since the connecting portions 11m also function as oil separating walls, the oil separating effect is improved.

As best shown in FIG. 8, the breather passage 45 opening at the intersection between the side wall 11f of the cylinder block 11 and the journal supporting wall 11h is formed by the side wall 11h.
f and a pair of breather passage partitions 56, 56. The breather passage 45 includes a first portion 45a extending in the axial direction of the crankshaft 19 along the side wall 11f of the cylinder block 11, and a crankshaft 19 orthogonal to the first portion 45a.
And a second portion 45b extending to the side. The large-diameter through-hole 11j opens at a connection portion between the first portion 45a and the second portion 45b, and has two small-diameter through-holes 11k, 1k.
Since 1k opens at both ends of the first portion 45a, it is possible to secure a passage area. Furthermore, small-diameter through holes 11k, 11k
Is formed so as to protrude between the side wall 11f of the cylinder block 11 and the weight portions 19b, 19b of the crankshaft 19, so that the passage area can be further increased.

A pair of breather passage partition walls 56, 56 connecting the side wall 11f of the cylinder block 11 and the journal support wall 11h are bent in a crank shape, and define a portion P that partitions both ends of the first portion 45a of the breather passage 45. , P extend from the side wall 11 f of the cylinder block 11 in a direction perpendicular to the axis of the crankshaft 19. In other words, the portions P, which define both ends of the first portion 45a, extend in a direction orthogonal to the side wall 11f of the cylinder block 11 at a position facing the weight portions 19b, 19b of the crankshaft 19, and then approach each other. And is connected to the journal support wall 11h.

As described above, the breather passage 4 having a T-shaped cross section is provided.
5 is formed at the intersection of the side wall 11f of the cylinder block 11 and the journal support wall 11h, so that the cross-sectional area of the breather passage 45 can be reduced without making the side wall 11f of the cylinder block 11 particularly thick or bulging. As a result, the flow rate of the blow-by gas passing therethrough can be reduced, and the amount of the lubricating oil flowing into the breather chamber 43 can be reduced.

Weight portions 19b, 19b (see FIG. 1) of the crankshaft 19 are disposed between the adjacent journal support walls 11h... The locus of movement of the weight portions 19b, 19b accompanying rotation of the crankshaft 19 is shown in FIG. 8 is indicated by a chain line. Portions P of the breather passage partition walls 56, 56 that define both ends of the first portion 45a of the breather passage 45,
P extends in a direction perpendicular to the side wall 11 f of the cylinder block 11, and a weight 19 of the crankshaft 19.
b and 19b are formed so as to have a minimum gap between them and the movement trajectory of the breather passage walls 56 and 19b.
Can avoid the interference with the weight portions 19b, 19b, and can maximize the cross-sectional area of the breather passage 45.

In FIG. 6, reference numeral 61 denotes an oil gallery formed in the cylinder block 11, which is lubricating oil supplied from the oil gallery 61 through an oil passage 62, and which lubricates the journals 19a of the crankshaft 19. Is done. The oil gallery 61 is arranged near the base of the lowermost rib 11c of the breather device 33. In FIG. 8, a lubricating oil return passage 63 for returning lubricating oil from the internal space of the cylinder head 12 to the oil pan 14 is formed at a connection between the three journal support walls 11h and the side wall 11f of the cylinder block 11. You.

The blow-by gas that has leaked from the combustion chamber 20 into the internal space of the crankcase 15 through the gaps around the pistons 17... Through the combustion chamber 20 along with the operation of the engine E passes through the breather passage 45 formed in the cylinder block 11. After that, it flows into the lower end of the breather chamber 43 of the breather device 33. The blow-by gas leaked from the intake ports 21 to the internal space of the cylinder head 12 through the clearance around the valve stem of the intake valves 23 is supplied to the cylinder block 1.
1, the breather passage 48, the through hole 11g and the groove 4
4 and flows into the middle part of the breather chamber 43 of the breather device 33. The blow-by gas flowing into the breather chamber 43 is supplied to the joint 4 at the upper end of the breather chamber 43.
The lubricating oil separated from the blow-by gas whose flow velocity has been reduced inside the breather chamber 43 formed in the labyrinth at this time is sucked into the intake system of the engine E through the breather passage 6 and the breather hose 47. It is returned to the oil pan 14 via 45.

While the embodiments of the present invention have been described in detail above, various design changes can be made in the present invention without departing from the gist thereof.

For example, as in the second embodiment shown in FIG. 9, the chamfers of the weight portions 19b, 19b of the crankshaft 19 are linear, and a part of the outer surfaces of the breather passage partition walls 56, 56 facing the chamfers. It may be linear.

In the embodiment, the breather passage 45 has been described. However, if the present invention is applied to the lubricating oil return passage, the passage sectional area of the lubricating oil return passage can be sufficiently ensured.

In the embodiment, three connecting holes 11m, 11m are formed by machining three circular through holes 11j, 11k, 11k in the bottom wall 11i between the breather chamber 43 and the breather passage 45. Are connected parts 11m and 11
m may be formed by casting, and the connecting portions 11m, 11m
The number and shape of m and the through holes 11j, 11k, 11k can also be changed as appropriate.

[0037]

As described above, according to the first aspect of the present invention, the first part and the second part are orthogonal to each other. And a passage partition partitioning both ends of a first portion extending in a direction along the side wall of the cylinder block of the passage, the passage partition partitioning along the movement locus of the weight portion of the crankshaft. It extends from the side wall of the block in the direction along the journal support wall, so that the passage partition does not interfere with the weight of the crankshaft, and without thickening or expanding the partition of the cylinder block, The maximum cross-sectional area can be ensured.

According to the invention described in claim 2,
A passage that opens to the bottom surface of the connection portion between the side wall of the cylinder block and the journal support wall is formed in a T-shape with a first portion and a second portion that are orthogonal to each other. Since the passage partition walls that define both ends of the first portion extending in the extending direction extend in the direction orthogonal to the side wall of the cylinder block at a position facing the weight portion of the crankshaft and are connected to the journal supporting wall, The space at the position facing the weight portion can be effectively utilized, and the cross-sectional area of the passage can be maximized.

According to the invention described in claim 3,
Since the passage partition that divides the passage is bridged and reinforced by the connecting portion, a decrease in the rigidity of the cylinder block due to the formation of the passage can be minimized.

According to the invention described in claim 4,
Since the connecting portion is formed between the plurality of through holes penetrating the bottom wall closing the passage, the connecting portion can be formed by a simple process of forming the through hole in the bottom wall.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an engine (a sectional view taken along line 1-1 in FIG. 2).

FIG. 2 is a view taken along line 2-2 of FIG. 1;

FIG. 3 is a view in the direction of arrows in FIG. 1;

FIG. 4 is a view taken in the direction of arrows 4-4 in FIG. 2;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 3;

FIG. 6 is a sectional view taken along line 6-6 in FIG. 2;

FIG. 7 is a view taken along line 7-7 in FIG. 3;

FIG. 8 is an enlarged view of part 8 of FIG. 7;

FIG. 9 is a view corresponding to FIG. 8 according to a second embodiment of the present invention.

DESCRIPTION OF SYMBOLS 11 Cylinder block 11f Side wall 11h Journal support wall 11i Bottom wall 11j Through hole 11k Through hole 11m Connecting portion 15 Crank case 19 Crank shaft 19b Weight portion 45 Breather passage (passage) 45a First portion 45b Second portion 56 Breather passage partition (passage partition)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F04B 9/04 F04B 9/04 B F-term (Reference) 3G013 AA06 AA07 BD04 3G015 AA05 AA07 BD10 BD23 BD24 BE05 BF03 BF05 BF08 CA02 3G024 AA38 AA47 AA56 BA23 BA24 DA10 DA18 3H075 BB03 CC15 DA03 DB04 DB29

Claims (4)

[Claims] An end of a passage (45) formed in a side wall (11f) of a cylinder block (11) integrally provided with a crankcase (15) is connected to the cylinder block (11).
In the passage structure of the cylinder block which is opened at the bottom surface of the connecting portion between the side wall (11f) and the journal support wall (11h), the opening of the passage (45) is
The first portion (4) extending in the direction along the side wall (11f) of (1).
5a) and a second portion (45b) orthogonal to the first portion (45a) and extending inside the journal support wall (11h), and formed in a T-shape. ), The passage partition (5)
6) is a weight portion (19) of the crankshaft (19).
Cylinder block (11) to follow the movement trajectory of b)
The passage structure of the cylinder block, which extends in a direction along the journal supporting wall (11h) from the side wall (11f) of the cylinder block. 2. An end of a passage (45) formed in a side wall (11f) of a cylinder block (11) integrally provided with a crankcase (15) is connected to the cylinder block (11).
In the passage structure of the cylinder block which is opened at the bottom surface of the connection portion between the side wall (11f) and the journal support wall (11h), the opening of the passage (45) is formed by the cylinder block (1).
The first portion (4) extending in the direction along the side wall (11f) of (1).
5a) and a second portion (45b) orthogonal to the first portion (45a) and extending inside the journal support wall (11h), and formed in a T-shape. ), The passage partition (5)
6) is a weight portion (19) of the crankshaft (19).
A passage structure of a cylinder block, wherein the passage structure extends in a direction orthogonal to a side wall (11f) of the cylinder block (11) at a position facing b) and is connected to a journal support wall (11h). 3. Inside the passage partition (56) that defines the passage (45), the passage partition (56) and the side wall (11f) of the cylinder block (11) are cross-linked at a connecting portion (11m). The passage structure of the cylinder block according to claim 1, wherein the passage structure is reinforced. 4. The connecting portion (11m) is connected to the passage (4).
5) formed between a plurality of through-holes (11j, 11k) penetrating through a bottom wall (11i) closing the bottom wall (11i);
The passage structure of the cylinder block according to claim 3.