JP4562962B2 - Structure of mounting part for engine auxiliary machinery - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure of an attachment part of an engine auxiliary machine, and more particularly to a structure of a part for attaching an auxiliary machine having an upper joint part and a lower joint part to an engine to a side surface of a lower crankcase of the engine. .
[0002]
[Prior art]
The same applicant as the present invention integrates an attachment part of an auxiliary machine such as an alternator or an air conditioner compressor with a side wall of a lower crankcase in which a bearing cap for supporting a crankshaft is integrally formed by die casting of an aluminum alloy. The structure to be formed was proposed in Japanese Patent Application No. 9-248773 (see Japanese Patent Application Laid-Open No. 11-82049). According to this, since the auxiliary machine mounting portion can be provided in a portion having high rigidity, the mounting rigidity of the auxiliary machine can be increased without labor without increasing the number of parts and the number of assembling steps.
[0003]
[Problems to be solved by the invention]
However, according to the above structure, since the oil pan is also integrally formed in the lower crankcase, for example, it is necessary to remove the auxiliary machine when maintaining the oil strainer provided in the suction port of the lubricating oil disposed in the oil pan. As a result, maintenance and maintainability tended to decline. In addition, since the upper joint portion of the auxiliary machine is not fastened to the flange that joins the upper crankcase in the lower crankcase, the rigidity of the flange has not been effectively utilized.
[0004]
The present invention has been devised to solve such problems of the prior art, and its main purpose is to increase the attachment rigidity of the auxiliary machine without increasing the number of parts and assembly man-hours. It is another object of the present invention to provide a structure of an auxiliary machine mounting portion that is configured so that maintenance and maintainability are not deteriorated.
[0005]
[Means for Solving the Problems]
In order to achieve such an object, in claim 1 of the present invention, in an engine in which an upper crankcase (17), a lower crankcase (18), and an oil pan (27) are joined, in the cylinder axial direction, The upper crankcase side with respect to the lower crankcase is the upper part, and the oil pan side with respect to the lower crankcase is the lower part, and an upper coupling part (4U) and a lower coupling part (4L) for the engine are formed. A flange that joins the upper crankcase in the lower crankcase to the upper boss (20U) to which the upper coupling portion is coupled is a structure of a portion for attaching the auxiliary machine (for example, the air conditioner compressor 4) to the side surface of the lower crankcase (18U) and lower bosses (20LF and 20LR) to which the lower joint is joined Flange (18L) is provided for joining the oil pan in Nkukesu, between the inner surface of the side wall of the lower crankcase, through strainer joint for joining the strainer (38) disposed in the oil pan (33) beam (40) in are connected to each other, and shall be characterized in that at least a portion of the lower boss provided on the outer surface of the beam connection.
[0006]
In this way, the oil pan can be attached and detached independently from the lower crankcase while ensuring the rigidity of the attachment portion of the auxiliary machine. Further, the span between the upper and lower coupling portions can be made long, and the flange has high rigidity, so that the mounting rigidity between the upper coupling portion and the lower coupling portion can be further increased. In addition, since the oil pan can be reduced in size without making the lower crankcase excessive, it is possible to improve the detachability of the oil pan. Furthermore, the inner side walls of the lower crankcase are connected to each other with a beam, and by providing at least a part of the lower boss on the outer surface of the beam connecting portion, it is possible to further increase the mounting rigidity of the lower coupling portion, The rigidity of the joint surface of the oil pan can also be increased.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
[0010]
1 and 2 show an in-line three-cylinder engine to which the present invention is applied. FIG. 1 is a view from the crank pulley side, and FIG. 2 is below the crankshaft along the center axis of the crankshaft. Each figure shows a cut view from the side.
[0011]
An alternator 2, a water pump 3, and an air conditioner compressor 4 are arranged in this order from the top on the side of the crank pulley side of the in-line three-cylinder engine 1. Each of these auxiliary machines is collectively driven by the power of the crankshaft 10 by a single (common) belt 9 wound between the pulleys 5 to 7 and the crank pulley 8 provided in the auxiliary machines. The tension of the belt 9 is adjusted at the position of the alternator 2.
[0012]
The crankshaft 10 and the camshaft 11 are linked together by timing pulleys 12 and 13 fixed to the shafts 10 and 11 and a timing belt 14 wound between the timing pulleys 12 and 13. Yes. Appropriate tension is applied to the timing belt 14 by a tensioner pulley 16 provided on the end face of the cylinder block 15 on the crank pulley side.
[0013]
The engine 1 includes an upper crankcase 17 that is integrated with the cylinder block 15, a lower crankcase 18 that is joined to the lower open end face of the upper crankcase 17, and a lower open end face that is on the front side of the lower crankcase 18. And an oil pan 27 (which will be described in detail later). Both the upper and lower crankcases 17 and 18 are formed by die-casting an aluminum alloy material, and are joined to each other on a plane through which the central axis of the crankshaft 10 passes. It is integrally connected with bolts.
[0014]
The lower crankcase 18 has a depth dimension corresponding to the desired oil storage capacity, and the side wall outer surface includes a plurality of auxiliary machines as shown in FIGS. Three bosses 20U, 20LF, and 20LR for screwing the mounting bolts 19 for the air conditioner compressor positioned at the lowermost position are formed.
[0015]
These bosses correspond to an upper joint portion 4U provided on the upper portion of the air conditioner compressor 4 and are arranged on one flange 18U that joins an upper crankcase formed at the upper end of the lower crankcase 18. Two lower bosses 20LF disposed on a flange 18L that joins an oil pan formed at the lower end of the lower crankcase 18 corresponding to the boss 20U and a lower coupling portion 4L provided at the lower portion of the air conditioner compressor 4・ It consists of 20LR. That is, the joint surface 29 with the oil pan described later is positioned below the center of the two lower bosses 20LF and 20LR.
[0016]
In this way, by extending the lower crankcase 18 downward, the air conditioner compressor 4 as an auxiliary device can be directly attached to the side surface of the lower crankcase 18, and a separate bracket is not necessary. In addition, since the air conditioner compressor 4 is fastened to the upper boss 20U at the upper end portion of the lower crankcase 18 and the lower bosses 20LF and 20LR at the lower end portion, the attachment span can be increased, so that the attachment rigidity can be improved. . Furthermore, the wall thickness of the upper and lower end portions of the lower crankcase 18 is larger than the other (side wall central portion, etc.) with flanges 18U and 18L formed, thereby further improving the mounting rigidity. Has contributed.
[0017]
Inside the upper crankcase 17, four bearing walls 23 a to 23 d on which upper halves 22 a to 22 d of main bearings for supporting the journal portions 21 a to 21 d of the crankshaft 10 are formed are suspended.
[0018]
As shown in FIGS. 3 and 4, lower halves 24 a to 24 d of the main bearing that cooperate with upper halves 22 a to 22 d of the four main bearings of the upper crank case 17 are formed inside the lower crankcase 18. Four bearing caps 25a to 25d are integrally formed.
[0019]
The oil pan joint flange 18L having a generally rectangular opening 26 is formed in a portion of the bottom portion of the lower crankcase 18 positioned below the first and second bearing caps 25a and 25b. An oil pan 27 formed by drawing a relatively shallow bottom with a steel plate is joined and fixed to the opening 26 with a plurality of bolts 28. As described above, by providing the steel plate oil pan 27 at the bottom, impact from below can be absorbed. In addition, by setting the height of the lower crankcase 18 so that it can be directly attached to the compressor 4 for the air conditioner, the size of the oil pan 27 made of a steel plate can be minimized, and the oil pan is joined to the lower crankcase 18. The machined surface for forming the surface 29 can be minimized. Accordingly, not only can the number of processing steps be reduced, but also the repair cost when the oil pan 27 is damaged can be reduced.
[0020]
The space between the bottom wall 18B below the third cylinder of the lower crankcase 18 and the bottom wall 27B of the oil pan 27 is used as an extension space for an exhaust pipe (not shown).
[0021]
A pump 30 such as a trochoid pump is provided at a position adjacent to the camshaft driving timing pulley 13 at the end of the crankshaft 10.
The pump 30 is joined to the outer end surface of the first bearing wall 23a of the cylinder block. A suction port 31 opened below the pump 30 has a first bearing cap at the end of the lower crankcase 18 on the crank pulley side. A pump inlet joint portion 32 formed at a portion adjacent to 25a is joined.
[0022]
A drooping portion 34, which is provided with a strainer joint 33 at the lower end thereof, is suspended from the lower end of the second bearing cap 25 b toward the opening 26. The strainer joint portion 33 and the pump inlet joint portion 32 are connected by a pipe-like portion 35 that extends linearly in an oblique direction and is joined to the lower end of the first bearing cap 25a. The pipe-like portion 35 is formed with an oil passage 36 that allows the lower surface of the strainer joint portion 33 and the upper surface of the pump suction port joint portion 32 to communicate with each other.
[0023]
In this way, the strainer joint portion 33 and the pipe-shaped portion 35 between each pair of bolt insertion boss portions AA for fastening the lower crankcase 18 to the upper crankcase 17 directly under the crankshaft 10 having a large explosion load. Is greatly formed, which contributes to improving the rigidity between the first and second bearing caps 25a and 25b. Therefore, since the support rigidity of the crankshaft 10 is further enhanced by this configuration, it is possible to reduce noise and vibration.
[0024]
In addition, since the oil passage 36 can be shortened by making the oil passage 36 straight, the amount of oil can be reduced, and not only the oil supply time to each part at the time of low temperature start can be shortened, but also the engine can be made compact. it can. Moreover, since it is straight, the passage 36 can be formed by casting from below, so that it can be formed simultaneously with the molding of the lower crankcase 28 and no post-processing is required.
[0025]
A strainer case 37 having a generally bottomed cylindrical shape is coupled to the lower surface of the strainer joint 33 in a state where a strainer 38 in which a wire mesh is formed into a truncated cone shape is sandwiched. The bottom wall of the strainer casing 3 7, has an oil inlet 39 is opened at a position biased to the outer circumferential side, the pump 30 is driven, oil in the oil pan 27 is a strainer casing from the inlet port 39 37, flows into the pump 30 through the strainer 38 and the oil passage 36, and is pumped to a predetermined oil supply passage.
[0026]
A beam 40 that connects the inner wall surfaces of the lower crankcase 18 extends through the strainer joint 33 in a direction perpendicular to the crankshaft 10. Since the front-rear direction intermediate portion of the opening 26 is connected by the beam 40, the rigidity of the flange 18L for joining the oil pan is further increased. Furthermore, an upward stay 42 is erected at a position corresponding to the crank pins 41 a to 41 c on the upper surface of the beam 40 and the inner surface of the bottom wall 18 </ b> B of the lower crankcase 18. A baffle plate 43 for suppressing the oscillation of the oil level inside is fixed with bolts 44.
[0027]
Thus, when the oil pan 27 is removed, the strainer case 37 is exposed, so that the strainer 38 can be easily maintained.
[0028]
Further, the boss 20LR protrudes from the outer surface of the connecting portion of the beam 40 with the right side wall of the lower crankcase 18, so that the rigidity of the boss 20LR is further enhanced.
[0029]
Although one embodiment of the present invention has been described for an in-line three-cylinder engine, the present invention is equally applicable to other types of engines. In particular, the present invention can be applied to an engine in which the cylinder axis is in the horizontal direction, and the lower crankcase 18 and the bearing caps 25a to 25d can be applied separately.
[0030]
【The invention's effect】
As described above, according to the present invention, the upper boss to which the upper coupling portion of the accessory is coupled and the lower boss to which the lower coupling portion are coupled are provided in the lower crankcase, and the oil pan joint surface with respect to the lower crankcase is provided on the lower boss. (Claim 1), the oil pan can be attached and detached from the lower crankcase independently while ensuring the rigidity of the attachment part of the auxiliary machine. A great effect can be achieved in increasing the attachment rigidity of the auxiliary machine without increasing the number of man-hours and lowering the maintenance / maintenance.
[0031]
In addition, an upper boss is provided on the flange to which the upper crankcase is joined in the lower crankcase, and a lower boss is provided on the flange to which the oil pan is joined in the lower crankcase (Claim 2). The span between the portions can be made long, and the flange has high rigidity, so that the mounting rigidity between the upper coupling portion and the lower coupling portion can be further increased. In addition, since the oil pan can be reduced in size without making the lower crankcase excessive, it is possible to improve the detachability of the oil pan.
[0032]
Further, the inner wall of the lower crankcase is connected to each other by a beam, and at least a part of the lower boss is provided on the outer surface of the beam connecting portion (Claim 3), thereby further increasing the mounting rigidity of the lower coupling portion. In addition, the rigidity of the joint surface of the oil pan can be increased.
[0033]
[Brief description of the drawings]
FIG. 1 is an elevational view as viewed from the crank pulley side of an engine to which the present invention is applied. FIG. 2 is a side sectional view taken along the axis of the crankshaft below the support portion of the crankshaft of the engine shown in FIG. FIG. 3 is a bottom view of the lower crankcase with the oil pan removed. FIG. 4 is a sectional view taken along line IX-IX in FIG. 3. FIG. 5 is a front right side view of the lower crankcase.
4 airconditioning compressor 4U upper portion coupling portion 4L under part coupling part 17 upper crankcase 18 Lower crankcase 18U · 18L flange 20U upper boss 20LF · 20LR lower boss 27 oil pan 29 oil pan joint surface 40 beam

Claims (1)

In an engine in which an upper crankcase, a lower crankcase, and an oil pan are joined, the upper crankcase side is an upper portion with respect to the lower crankcase in the cylinder axial direction, and the oil pan side with respect to the lower crankcase Is an attachment structure of a portion for attaching an auxiliary machine formed with an upper joint portion and a lower joint portion to the engine to a side surface of the lower crankcase,
An upper boss to which the upper coupling portion is coupled is provided on a flange for joining the upper crankcase in the lower crankcase, and a lower boss to which the lower coupling portion is coupled is a flange for joining the oil pan in the lower crankcase provided,
The inner side walls of the lower crankcase are connected to each other by a beam via a strainer joint for joining a strainer disposed in the oil pan, and at least a part of the lower boss is formed on the outer surface of the beam connection. The structure of the attachment part of the engine auxiliary machine characterized by the above.

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