Technical Field
[0001] The present invention relates to an oil pan for an internal combustion engine mounted
on a vehicle.
Background Art
[0002] An oil pan for an internal combustion engine (hereinafter, referred to as engine)
mounted on a vehicle is provided in the lowermost part of the engine, and has mainly
a role of storing the engine oil used in the engine. The engine oil stored in the
oil pan is sucked up by an oil pump operating on part of the engine power, is supplied
to revolving portions, sliding portions and the like, and lubricates these portions
to reduce the frictional resistance. The engine oil having lubricated the inside of
the engine becomes oil drops which move along the wall and drop into the oil pan.
Then, the engine oil is again sucked up by the oil pump to thereby circulate in the
engine. For the oil pan, a capacity sufficient for storing the total quantity of engine
oil used in the engine is secured.
[0003] There are cases where it is necessary to detach the oil pan from the engine body
such as when an oil leak from the engine occurs or when deterioration, damage or the
like occurs on the oil pan. In general vehicles, in order that the detachment and
attachment of the oil pan can be performed from below the vehicle body, the vehicle
body members and other devices are provided in positions that do not hinder the detachment
and attachment of the oil pan, or are structured so as to be detachable from the vehicle
body at the time of detachment and attachment of the oil pen. Oil pans include a type
where a fin and partitions are provided inside the oil pan and an oil pan of a type
divided into two pieces one above the other, formed of an upper oil pan and a lower
oil pan (see Patent Document 1).
Prior Art Document
Patent Document
Summary of the Invention
Problem that the Invention is to Solve
[0005] However, members and devices provided below the oil pan so as to overlap the oil
pan cannot be detached in some vehicles. Therefore, an oil pan detached and attached
after vehicle body members and devices are detached cannot be applied to such vehicles.
Although it is considered to reduce the size of the oil pan by changing the shape
thereof in order to secure applicability to such vehicles, it is necessary that a
predetermined capacity sufficient for storing the total quantity of oil required for
the engine be secured for the oil pan. Therefore, the size of the oil pan is restricted
to some extent and cannot be reduced indiscriminately, and it is difficult to achieve
both the detachment/attachment performance and the securing of the capacity.
[0006] An object of the present case is to provide an oil pan for an internal combustion
engine that is invented in view of the above-mentioned problem and can be easily detached
and attached from and to the body of the internal combustion engine while a capacity
capable of storing the total quantity of oil required is secured.
[0007] Not only this object but also producing an operational advantage derived from the
structures shown in the later-described mode for carrying out the invention which
operational advantage cannot be obtained from the conventional art can be placed as
another object of the present case.
Means for Solving the Problem
[0008] (1) An oil pan for an internal combustion engine disclosed herein is an oil pan for
an internal combustion engine mounted on a vehicle provided with a pair of right and
left side members provided so as to extend in a front-rear direction of the vehicle
and a cross member provided so as to extend in a width direction of the vehicle and
fixed to the pair of side members, and is characterized by being of a type divided
into two pieces one above the other, formed of an upper oil pan attached to a body
of the internal combustion engine and including an opening in a bottom portion and
a lower oil pan attached so as to cover the opening of the upper oil pan from below,
by including an overlapping portion situated above the cross member and overlapping
the cross member, and in that the lower oil pan is provided so as to be situated in
front of or behind the overlapping portion so as to include the overlapping portion
in a state of being mounted on the vehicle.
[0009] The "overlapping portion" referred to here indicates a portion where the oil pan
overlaps the cross member in the top-bottom direction.
[0010] (2) It is preferable that an upper surface of the cross member be formed so as to
incline upward or downward from a front end portion to a rear end portion and a bottom
portion, opposed to the cross member, of the lower oil pan be formed so as to incline
upward or downward from a front end side of the overlapping portion to a rear end
side of the overlapping portion and have a substantially uniform distance from the
upper surface portion of the cross member. In other words, it is preferable that the
upper surface of the cross member and the bottom portion of the lower oil pan both
incline in the same direction of upward or downward from the front to the rear and
these be provided substantially parallel to each other.
[0011] (3) Moreover, it is preferable that at least the lower oil pan be provided so as
to extend frontward beyond a front end portion of the internal combustion engine or
rearward beyond a rear end portion thereof.
Advantage of the Invention
[0012] According to the disclosed oil pan for the internal combustion engine, since the
oil pan is of the type divided into two pieces one above the other formed of the upper
oil pan and the lower oil pan and the lower oil pan is provided so as to be situated
in front of or behind of the overlapping portion, when the oil pan is detached, it
is possible to detach the lower oil pan first. This facilitates the detachment of
the upper oil pan. On the other hand, when the oil pan is attached, it is possible
to attach the upper oil pan first and then, attach the lower oil pan. Consequently,
for example, even on a vehicle where the cross member cannot be detached from the
vehicle body, the attachment and detachment of the oil pan can be performed. Further,
since the lower oil pan is provided so as to include the overlapping portion, the
capacity of oil that can be stored can be increased, and a capacity capable of storing
the total quantity of oil required can be secured. That is, the detachment/attachment
performance and the securing of the capacity of the oil pan can be both achieved.
Brief Description of the Drawings
[0013]
[FIG. 1] A bottom view of a vehicle mounted with an oil pan for an internal combustion
engine according to an embodiment.
[FIG. 2] A perspective view, viewed from above, showing the structure of the oil pan
for the internal combustion engine according to the embodiment.
[FIG. 3] Views showing the structure of the oil pan for FIG. 2, FIG. 3(a) being a
top view, FIG. 3(b) being a bottom view, FIG. 3(c) being a side view, and FIG. 3(d)
being a cross-sectional view on arrow A-A of FIG. 3(a).
[FIG. 4] A view explaining the positional relation between the oil pan for the internal
combustion engine according to the embodiment and the cross member.
[FIG. 5] Views explaining the procedures of detaching the oil pan for the internal
combustion engine according to the embodiment, FIG. 5 (a) being the detachment of
a lower oil pan, and FIG. 5(b) being the detachment of an upper oil pan.
Mode for Carrying out the Invention
[0014] Hereinafter, an embodiment will be described by using the drawings. The embodiment
shown below is merely illustrative, and it is not intended to exclude various modifications
and technical applications not clearly shown in the embodiment shown below. In the
following description, the direction of travel of the vehicle is the forward direction,
the right and the left are determined with reference to the frontward direction, the
direction of the gravity is the downward direction and the direction opposite thereto
is the upward direction in giving the description. In the description of devices and
parts mounted on a vehicle, the top-bottom direction, the right-left direction and
the front-rear direction are determined with reference to the condition where those
devices and parts are mounted on the vehicle.
[1. Structure]
[0015] As shown in FIG. 1, an internal combustion engine 1 (hereinafter, referred to as
engine 1) according to the present embodiment is mounted on the front side of the
vehicle, and disposed between a pair of right and left side members 2 provided so
as to extend in the front-rear direction of the vehicle with a distance from each
other. Between the side members 2, a clutch housing 3 and a transmission 4 are mounted
behind the engine 1. While various devices are mounted on the vehicle in addition
to these, they are omitted in FIG. 1.
[0016] A cross member 5 provided so as to extend in the vehicle width direction (right-left
direction) is provided below an oil pan 10 provided in the lowermost part of the engine
1. This cross member 5 is a front suspension cross member having, at left and right
end portions 5c and 5d, connection portions that receive the springs (not shown) of
the suspensions. The cross member 5 is fixed to the pair of side members 2 by welding
on the inner side of the left and right end portions 5c and 5d in the vehicle width
direction. The cross member 5 is formed of an a hat-shaped upper member 51 whose longitudinal
cross section in the front-rear direction has an opening in the lower surface and
a sheet-metal-form lower member 55 joined to the lower surface in an intermediate
part of the upper member 51 in the vehicle width direction so as to cover the opening
(see FIG. 4).
[0017] In this example, the upper member 51 of the cross member 5 has, as shown in FIG.
2 and FIG. 4, an upper surface portion 52 extending in the vehicle width direction,
two upright surface portions extending downward from both ends in the width direction
of the upper surface portion 52 (that is, the front-rear direction of the vehicle)
and two flange portions provided so as to protrude outward in the horizontal direction
from both lower ends of the two upright surface portions. The upper surface portion
52 of the upper member 51 (hereinafter, referred to as the upper surface portion 52
of the cross member 5) is formed so as to incline downward from a front end portion
52a to a rear end portion 52b.
[0018] Moreover, in a lower part of the vehicle, a steering linkage 6 which is a rack-and-pinion
steering device is provided so as to extend in the vehicle width direction. A steering
rack housing 6a of this steering linkage 6 is situated below the oil pan 10, and situated
in front of and above the cross member 5 (see FIG. 4). In the present embodiment,
a vehicle where the cross member 5 situated below the oil pan 10 cannot be detached
from the vehicle body (vehicle body such as the side members 2) is shown as an example.
[0019] The oil pan 10 is situated above the cross member 5 and the steering rack housing
6a, and has an overlapping portion (the dotted part in FIG. 1) that overlaps the cross
member 5. The overlapping portion 11 referred to here is a superposing portion of
the oil pan 10 and the upper surface portion 52 of the cross member 5. This superposing
portion is a portion where the oil pan 10 and the upper surface portion 52 of the
cross member 5 overlap in the top-bottom direction.
[0020] The oil pan 10 is a container (receiving pan) storing the engine oil (hereinafter,
sometimes referred to as oil) used in the engine 1, and is attached to the bottom
of the main body of the engine 1 (hereinafter, referred to as engine body). The oil
stored in the oil pan 10 is sucked up through an oil strainer 7 [see FIG. 3(a)] by
a non-illustrated oil pump operating on part of the power of the engine 1, is sent
to revolving portions, sliding portions and the like to lubricate and reduce frictional
resistance. The oil also has a role of cooling the revolving portions, the sliding
portions and the like, and after lubricating and cooling the inside of the engine
1, becomes oil drops which move along the cylinder wall and the like and drop into
the oil pan 10. By this being repeated, the oil circulates in the engine 1. The engine
body referred to here indicates an engine block excluding the oil pan 10 (a cylinder
head and a cylinder block are included).
[0021] The oil strainer 7 is a filter provided at an end of the intake of the oil pump,
and is provided slightly above the bottom surface of a later-described lowermost portion
23e in the oil pan 10. To the oil strainer 7, a rather coarse net is attached to prevent
large foreign substances mixed in the oil from being sucked in when the oil is sucked
in. Moreover, a filter for removing finer foreign substances is provided on the circulation
route of the oil. The capacity of the oil pan 10 corresponds to the total amount of
oil used (required) in the engine 1.
[0022] Next, the structure of the oil pan 10 will be described by using FIG. 2, FIGS. 3(a)
to 3(d) and FIG. 4. As shown in FIG. 4, the oil pan 10 is of the type divided into
two pieces one above the other, formed of an upper oil pan 20 on the upper side and
a lower oil pan 30 on the lower side, and a combination of these upper oil pan 20
and lower oil pan 30 constitutes one oil pan 10. The upper oil pan 20 is formed, for
example, of a casting, and the lower oil pan 30 is formed, for example, of a sheet
metal. The broken line in FIG. 4 illustrates the water surface of oil when oil is
stored in the oil pan 10.
[0023] As shown in FIG. 2 and FIGS. 3(a) and 3(d), the upper oil pan 20 is provided with
an upper surface open portion 21h in an upper part, and has a peripheral wall portion
22 provided so as to extend downward from the perimeter of the upper surface open
portion 21h and a bottom portion 23 formed in a shape substantially the same as the
upper surface open portion 21h when viewed from above. Around the upper surface open
portion 21h (that is, on the upper end portion of the peripheral wall portion 22),
a flange portion 21f provided so as to protrude outward substantially horizontally
is provided. The upper surface open portion 21h is formed in a shape substantially
the same as the opening provided in the lower surface of the cylinder block. The inside
of the engine 1 and the inside of the oil pan 10 communicate with each other through
the opening in the lower surface of the cylinder block and the upper surface open
portion 21h.
[0024] Into the flange portion 21f, a plurality of bolts 21t are inserted from below in
the peripheral direction (around the upper surface open portion 21h). These bolts
21t are screwed into holes (not shown) formed in the lower end surface of the cylinder
block, thereby fixing the upper oil pan 20 and the engine body. When the upper oil
pan 20 is attached to the engine body, a seal member such as a liquid gasket is sandwiched
between the upper surface of the flange portion 21f and the lower end surface of the
cylinder block, thereby sealing the joint surfaces of the cylinder block and the upper
oil pan 20.
[0025] As shown in FIGS. 3 (c) and 3 (d), an inclined portion 23s provided so as to extend
in the vehicle width direction and inclined downward more smoothly as it approaches
the rear side is formed substantially in a central part, in the front-rear direction,
of the bottom portion 23 of the upper oil pan 20. That is, the bottom portion 23 is
formed so that the surface behind the inclined portion 23s is situated lower than
the surface of the front side thereof. The upper oil pan 20 is formed so that the
vertical length H
2 behind the inclined portion 23s is larger than the vertical length H
1 on the front side.
[0026] Hereinafter, a bottom portion behind the inclined portion 23s (that is, of the bottom
portion 23 of the upper oil pan 20, a portion situated in the lowermost position)
will be specifically referred to as the lowermost portion 23e. As shown in FIG. 2
and FIGS. 3(a) and 3(b), a substantially rectangular bottom open portion (opening)
23h passing through the bottom portion 23 is formed in the lowermost portion 23e.
The area of opening of the bottom open portion 23h is smaller than that of the upper
surface open portion 21h.
[0027] As shown in FIG. 3(d), the upper oil pan 20 has, in a rear portion 22Rb of a portion
of the peripheral wall portion 22 extending in the front-rear direction on the right
side (hereinafter, referred to as right wall portion 22R), a wall open portion 22h
passing through the right wall portion 22R. The wall open portion 22h is situated
above the bottom open portion 23h, and communicates with the bottom open portion 23h.
That is, the upper oil pan 20 has the open portions 21h, 23h and 22h in an upper part,
in the lowermost portion 23e of the bottom portion 23 and in the rear portion 22Rb,
respectively.
[0028] Moreover, the upper oil pan 20 has, as shown in FIG. 2 and FIGS. 3(a) and 3(d), a
lid 24 provided so as to cover the wall open portion 22h from the outside. The lid
24 is provided so that an opened one end portion 24a is connected to the outer side
of the right wall portion 22R and that a closed other end portion 24b protrudes to
the rear side of a rear end portion 10b of the oil pan 10 (that is, a rear end portion
1b of the engine 1). Moreover, an intermediate portion 24c (between the one end portion
24a and the other end portion 24b) of the lid 24 is formed so as to be bent. The lid
24 is formed so that a longitudinal cross section in a direction orthogonal to a direction
extending from the one end portion 24a to the other end portion 24b has a hat shape
the lower surface of which is opened. On the lower surface of the lid 24, a lid open
portion 24h is formed, and further, around the lid open portion 24h except for the
one end portion 24a, a flange portion 24f provided so as to protrude outward substantially
horizontally is formed.
[0029] The lower surface of the lid 24 (that is, the surface of the lid open portion 24h
and the flange portion 24f) is provided so as to be flush with the lower surface of
the lowermost portion 23e of the upper oil pan 20, and the lid open portion 24h and
the bottom open portion 23h communicate with each other through the wall open portion
22h. The upper surface of the lid 24 is provided slightly below the surface where
the upper surface open portion 21h of the upper oil pan 20 is provided. The shape
of the lid 24 when viewed from above is the same as the shape of a later-described
extended portion 34 of the lower oil pan 30 when viewed from above.
[0030] The lower oil pan 30 is, as shown in FIGS. 3(b) to 3(d), attached to the upper oil
pan 20 so as to cover the bottom open portion 23h and the 24h of the upper oil pan
20 from below. That is, the lower oil pan 30 is provided in a lower part of the oil
pan 10 (below the upper oil pan 20) and in a rear part of the oil pan 10 (behind the
inclined portion 23s of the upper oil pan 20).
[0031] The lower oil pan 30 is provided with a lower side open portion 31h in an upper part,
and has a lower side peripheral wall portion 32 provided so as to extend downward
from the perimeter of the lower side open portion 31h and a lower side bottom portion
33 formed in a shape substantially the same as the lower side open portion 31h when
viewed from above. Around the lower side open portion 31h (that is, on the upper end
portion of the lower side peripheral wall portion 32), a lower side flange portion
31f provided so as to protrude outward substantially horizontally is provided. The
lower side open portion 31h is formed in a shape the same as a shape which is a combination
of the bottom open portion 23h, the lid open portion 24h and the length portion, in
the right-left direction, of the wall open portion 22h (part corresponding to the
thickness of the peripheral wall portion 22) of the upper oil pan 20.
[0032] In the lower side flange portion 31f, a plurality of lower side bolts 31t are inserted
from below in the peripheral direction (around the lower side open portion 31h). These
lower side bolts 31t are screwed into holes provided on the side of the upper oil
pan 20 and nuts and the like embedded therein (none of these are shown). Thereby,
the lower oil pan 30 is attached to the upper oil pan 20. When these are joined, a
seal member such as a liquid gasket is sandwiched between the joint surfaces to seal
the joint surfaces.
[0033] When the lower oil pan 30 is attached to the upper oil pan 20, the bottom open portion
23h, the lid open portion 24h and the length portion, in the right-left direction,
of the wall open portion 22h on the side of the upper oil pan 20 coincide with the
lower side open portion 31h on the side of the lower oil pan 30, so that one opening
through which the upper oil pan 20 and the lower oil pan 30 communicate with each
other is formed.
[0034] As shown in FIGS. 3(c) and 3(d), the lower side bottom portion 33 has a lower side
inclined portion 33s inclined downward more smoothly as it approaches the rear side
from a front end portion 33a. The lower side inclined portion 33s is, as shown in
FIG. 4, provided up to the neighborhood of substantially the central part, in the
front-rear direction, of the lower oil pan 30 so as to include the position overlapping
the upper surface portion 52 of the cross member 5 in the top-bottom direction (that
is, the overlapping portion 11). In other words, the lower side inclined portion 33s
is part of the lower side bottom portion 33 formed so as to incline downward from
the front end side to the rear end side of the overlapping portion 11. The lower side
inclined portion 33s is formed at an inclination angle substantially the same as the
inclined portion 23s formed on the bottom portion 23 of the upper oil pan 20. Moreover,
the lower side inclined portion 33s is substantially parallel to the upper surface
portion 52 of the cross member 5.
[0035] Moreover, as shown by the broken line in FIG. 3(b), the lower side bottom portion
33 is formed of a rectangular bottom portion 33A situated substantially immediately
below the bottom open portion 23h of the upper oil pan 20 when viewed from below the
oil pan 10, and having substantially the same shape as the bottom open portion 23h
and an extended bottom portion 33B provided so as to extend from the right side portion
of the rectangular bottom portion 33A outside toward the right and formed so as to
bent rearward in an intermediate part. The extended bottom portion 33B has a shape
substantially the same as a shape which is a combination of the lid open portion 24h
and the length portion, in the right-left direction, of the wall open portion 22h,
and a rear end portion 33Bb thereof is situated behind the rear end portion 10b of
the oil pan 10.
[0036] The lower oil pan 30 has, as shown in FIG. 2 and FIG. 3(b), an extended portion 34
extended so as to protrude outward from a portion of the lower side peripheral wall
portion 32 extending in the front-rear direction on the right side (hereinafter, referred
to as lower side right wall portion 32R), behind substantially the central part, in
the front-rear direction, of the lower oil pan 30. The extended portion 34 is provided
in order to further increase the capacity of the oil pan 10, and the shape thereof
is determined by the arrangement relation with various devices and members other than
the engine 1 mounted on the vehicle.
[0037] In this example, as shown in FIG. 1, the extended portion 34 is extended so as to
be situated below the right front portion of the clutch housing 3. The extended portion
34 is formed of the extended bottom portion 33B of the lower side bottom portion 33
and part of the lower side peripheral wall portion 32 provided upright on the peripheral
end portion of the extended bottom portion 33B. The extended portion 34 is a portion
joined immediately below the lid 24 when the upper oil pan 20 and the lower oil pan
30 are combined together. The open portion on the upper surface of this extended portion
34 (that is, the portion of the lower side open portion 31h situated at the extended
portion 34) is sealed by the above-described lid 24 of the upper oil pan 20.
[0038] As shown in FIG. 2 and FIG. 3(b), to the right end portion of the extended portion
34, a drain bolt 35 is attached with a drain washer 36 in between. The drain bolt
35 is for draining the oil stored in the oil pan 10, and is detached from the oil
pan 10 together with the drain washer 36 in cases such as when the oil pan 10 is detached
from the engine body and when oil is changed.
[0039] Next, the arrangement relation will be described among the oil pan 10, the cross
member 5 and the steering rack housing 6a when the oil pan 10 formed of a combination
of the upper oil pan 20 and the lower oil pan 30 structured as described above is
mounted on a vehicle. As shown in FIG. 4, the oil pan 10 is provided so as to incline
so that the rear end portion 10b is situated slightly below the front end portion
10a.
[0040] As shown in FIG. 4, the lower oil pan 30 is provided so as to be situated behind
the overlapping portion 11 so as to include the overlapping portion 11 overlapping
the cross member 5. In other words, the lower oil pan 30 is provided in a position
where the front end portion of the lower side flange portion 31f substantially overlaps
the front end portion of the upper surface portion 52 of the cross member 5 in the
top-bottom direction. The upper oil pan 20 is provided so that the bottom portion
23 on the front side including the inclined portion 23s is situated in front of the
steering rack housing 6a so as to include the steering rack housing 6a.
[0041] The oil pan 10 is disposed so that the bottom portion 23 of the upper oil pan 20
and the lower side bottom portion 33 of the lower oil pan 30 are at a substantially
uniform distance from the steering rack housing 6a and the upper surface portion 52
of the cross member 5. This is done in order not only to prevent contact among the
oil pan 10, the cross member 5 and the steering rack housing 6a but also to smoothly
detach and attach the oil pan 10 from and to the engine body.
[0042] If this distance can be reduced, the bottom portions 23 and 33 of the oil pan 10
can be provided in lower positions accordingly, so that the capacity of the oil pan
10 can be increased. The oil pan 10 of the present embodiment has a structure as described
above by minimizing this distance to increase the capacity and considering the detachment/attachment
performance. Hereinafter, the detachment and attachment of the oil pan 10 from and
to the engine body will be described.
[2. Oil Pan Detachment and Attachment Procedures]
[0043] Using FIGS. 5 (a) and 5(b), a procedure of detaching the oil pan 10 from the engine
body and a procedure of attaching it to the engine body will be described. FIG. 5(a)
shows the locus of detachment of the lower oil pan 30, and FIG. 5 (b) shows the locus
of detachment of the upper oil pan 20. The loci of attachment of the upper oil pan
20 and the lower oil pan 30 are the reverse of the detachment loci.
[0044] When the oil pan 10 is detached from the engine body, first, the engine 1 is slightly
lifted to slightly increase the distance (space) between the bottom portion 23 of
the upper oil pan 20 and the lower side bottom portion 33 of the lower oil pan 30,
and the steering rack housing 6a and the upper surface portion 52 of the cross member
5. Then, the steering rack housing 6a is detached from the vehicle body. Then, the
drain bolt 35 and the drain washer 36 are detached and the oil inside is drained.
[0045] Further, the lower oil pan 30 is detached from the upper oil pan 20, and then, the
upper oil pan 20 is detached from the engine body. This is because in the present
embodiment, since the cross member 5 cannot be detached from the vehicle body (the
vehicle body such as the side members 2), the oil pan 10 cannot be detached only by
slightly increasing the space below the oil pan 10.
[0046] As shown in FIG. 5(a), when the lower oil pan 30 is detached from the upper oil pan
20, first, the joint surfaces of the upper oil pan 20 and the lower oil pan 30 are
peeled off so that the lower oil pan 30 is movable. Then, as shown by the arrow A,
the lower oil pan 30 is moved downward and brought down to the neighborhood of the
cross member 5 (chain double-dashed line in the figure). Then, as shown by the arrow
B, the lower oil pan 30 is pulled out toward the rear side of the vehicle body under
that state (thick solid line in the figure). As described above, by detaching the
lower oil pan 30 first, the space below the upper oil pan 20 can be further increased.
[0047] As shown in FIG. 5(b), when the upper oil pan 20 is detached from the engine body,
first, the joint surfaces of the lower oil pan 30 and the cylinder block are peeled
off so that the upper oil pan 20 is movable. Then, as shown by the arrow C, the upper
oil pan 20 is moved downward and brought down to the neighborhood of the cross member
5 (chain double-dashed line in the figure). Then, as shown by the arrow D, the rear
end of the upper oil pan 20 is slightly inclined downward (broken line in the figure).
Then, as shown by the arrow E, the upper oil pan 20 is pulled out toward the rear
side of the vehicle body under that state (thick solid line in the figure).
[0048] The vertical length H
2 behind the inclined portion 23s of the upper oil pan 20 is a length where the upper
oil pan 20 can be pulled out in the inclined state toward the rear side of the vehicle
from the space between the cross member 5 and the clutch housing 3.
[0049] On the other hand, when the oil pan 10 is attached to the engine body, the attachment
is performed by a procedure reverse to the procedure of detachment of the oil pan
10. That is, first, the upper oil pan 20 is pushed in toward the front side of the
vehicle from the space between the cross member 5 and the clutch housing 3, the upper
oil pan 20 is inclined for attachment to the engine body, moved upward, and attached
to the engine body with the seal member in between.
[0050] Then, the lower oil pan 30 to which the drain bolt 35 and the drain washer 36 are
attached is pushed in up to below the upper oil pan 20 from the rear side of the vehicle,
moved upward, and attached to the upper oil pan 20 with the seal member in between.
Then, engine oil is poured into the engine body, the steering rack housing 6a is attached
to the vehicle body, and the position of the engine 1 is returned to the original
position.
[3. Advantage]
[0051] Consequently, according to the oil pan 10 of the present embodiment, since it is
structured as the type divided into two pieces one above the other of the upper oil
pan 20 and the lower oil pan 30 and the lower oil pan 30 is provided so as to be situated
behind the overlapping portion 11 so as to include the overlapping portion 11, it
is possible to detach only the lower oil pan 30 first in the detachment of the oil
pan 10. This facilitates the detachment of the upper oil pan 20.
[0052] On the other hand, in the attachment of the oil pan 10, it is possible to attach
the upper oil pan 20 first and then, attach the lower oil pan 30. Thereby, the oil
pan 10 can be detached and attached even from and to a vehicle where the cross member
5 cannot be detached from the vehicle body as described above. Further, since the
lower oil pan 30 is provided so as to include the overlapping portion 11, the capacity
of the storable oil can be increased, so that the total quantity of oil required by
the engine 1 can be secured. Consequently, the detachment/attachment performance and
the securing of the capacity of the oil pan 10 can be both achieved.
[0053] Moreover, since the upper surface portion 52 of the cross member 5 is formed so as
to incline downward from the front end portion 52a to the rear end portion 52b, the
lower side bottom portion 33 of the lower oil pan 30 is formed so as to incline downward
from the front end side to the rear end side of the overlapping portion 11 and there
is a substantially uniform distance from the upper surface portion 52, the lower oil
pan 30 can be smoothly pulled out toward the rear side of the vehicle. When the lower
oil pan 30 is attached, contact with the cross member 5 can be easily avoided. Consequently,
the detachment/attachment performance of the oil pan 10 can be further improved.
[0054] Moreover, since the lower oil pan 30 has the extended portion 34 provided so as to
extend up to the rear side of the rear end portion 1b of the engine 1, the total quantity
of oil that can be stored in the oil pan 10 can be increased. Thereby, the capacity
of the oil pan 10 can be easily secured.
[0055] Since the oil pan 10 is of the type divided into two pieces one above the other,
formed of the upper oil pan 20 and the lower oil pan 30, the degree of freedom of
the shape is high compared with an integral oil pan. Moreover, since the lower oil
pan 30 is formed of a sheet metal, a shape that does not interfere with surrounding
devices and members can be easily formed. Moreover, by changing the shape of the lower
oil pan 30, the capacity of the oil pan 10 can be easily changed.
[0056] Moreover, in this example, since the wall open portion 22h is formed on part of the
peripheral wall portion 22 of the upper oil pan 20 and the lid 24 whose longitudinal
cross section in the direction orthogonal to the direction extending from the one
end portion 24a to the other end portion 24b is hat-shaped is provided, the capacity
of the oil pan 10 can be further increased.
[4. Modifications]
[0057] While an embodiment of the present invention has been described above, the present
invention is not limited to the above-described embodiment, and may be modified variously
without departing from the gist of the present invention.
[0058] While in the above-described embodiment, the extended portion 34 of the lower oil
pan 30 is provided so as to extend rearward beyond the rear end portion 1b of the
engine 1, the shape and position of the extended portion 34 are not limited thereto,
and the shape and position thereof are determined by the arrangement relation with
various devices and members other than the engine 1 mounted on the vehicle. For example,
the extended portion 34 may be provided so as to extend further behind the rear end
portion 1b of the engine 1 or conversely, may be provided so as to extend only sideward.
When the capacity of the oil pan 10 is sufficiently secured, the extended portion
34 may be omitted.
[0059] The wall open portion 22h is not necessarily formed in the upper oil pan 20, and
the lid 24 is not necessarily hat-shaped in cross section. For example, a planar lid
member may be provided at the open portion on the upper surface of the extended portion
34 provided on the lower oil pan 30 (that is, the part of the lower side open portion
31h situated at the extended portion 34) to seal this open portion. In this case,
since the lid member sealing the extended portion 34 has a simple shape, the structure
of the oil pan 10 can be simplified.
[0060] Moreover, the position where the lower oil pan 30 is attached is not limited to the
above-described one since it is determined according to the position of the cross
member 5. Moreover, while in the above-described embodiment, the lower oil pan 30
is provided so as to be situated behind the overlapping portion 11 so as to include
the overlapping portion 11 since the steering linkage 6 is provided in front of the
cross member 5, when the position of the steering linkage 6 is different from the
above-mentioned one, the lower oil pan 30 may be provided so as to be situated in
front of the overlapping portion 11 so as to include the overlapping portion 11.
[0061] Moreover, in this case, it is preferable that the upper surface portion 52 of the
cross member 5 be formed so as to incline upward from the front end portion 52a to
the rear end portion 52b and it is preferable that the part of the lower side bottom
portion 33 of the lower oil pan 30 opposed to the cross member 5 be formed so as to
incline upward from the front end side to the rear end side of the overlapping portion
11. The upper surface of the cross member 5 and the bottom portion of the lower oil
pan 30 are not necessarily formed so as to incline.
[0062] While the present oil pan 10 is suitable for use in vehicles where the cross member
5 cannot be detached from the vehicle body, it is to be noted that it is also applicable
to vehicles where the cross member 5 is detachable from the vehicle body.
Description of Reference Numerals and Signs
[0063]
1 Engine (internal combustion engine)
2 Side member
5 Cross member
52 Upper surface portion
10 Oil pan
11 Overlapping portion
20 Upper oil pan
23 Bottom portion
23e Lowermost portion
23h Bottom open portion (opening)
30 Lower oil pan
33 Lower side bottom portion
33s Lower side inclined portion
34 Extended portion