JP2016008589A - Flywheel cooling structure of engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flywheel cooling structure of an engine which can suppress the wear of a clutch disc by surely and stably cooling a flywheel, without involving increase in the cost of the flywheel cooling structure.SOLUTION: A flywheel 7 is fixed to an external end 1c of a crank shaft 1 protruding from a cylinder block 3 in which a lubricating oil passage 4 for supplying lubricating oil to parts 1a, 1b to be lubricated is formed, a clutch disc 9 of a clutch mechanism 8 is separably arranged at the flywheel 7, a lubricating oil passage 13 for lubricating the lubricating oil is formed in the flywheel 7, and the lubricating oil passage 4 of the crank shaft 1 is extended so as to communicate with the lubricating oil passage 13.

Description

  The present invention relates to an engine flywheel cooling structure in which a flywheel fixed to an outer end portion of a crankshaft is cooled to cool a clutch disk abutting against the flywheel.

  In an automobile engine, a clutch disk coupled to an input shaft of a transmission mechanism is pressed against a flywheel fixed to an outer end portion of a crankshaft, thereby transmitting engine output to the transmission mechanism and releasing the pressure contact. A clutch mechanism for shutting off the engine output is provided.

The clutch mechanism has a problem that the flywheel and the clutch disk are heated to high temperatures due to frictional heat, so that the clutch disk is easily worn. Therefore, a cooling structure has been proposed in which a ventilation hole is provided in the flywheel to cool the flywheel to prevent overheating of the clutch disk and thereby suppress wear of the clutch disk (see Patent Document 1).

Japanese Utility Model Publication No. 5-79083

Since the clutch mechanism is housed in a clutch housing which is a substantially sealed space, cooling by the air flowing through the ventilation holes is not sufficient, and it is more reliable to suppress wear of the clutch disk. A stable cooling structure is required.

In addition, there is a problem that the cost is increased when a material for heat damage countermeasures that has high heat resistance and is not easily worn at high temperatures is used for the clutch disk.

The present invention has been made in view of the above-described conventional circumstances, and it is possible to suppress the wear of the clutch disk by reliably and stably cooling the flywheel, and to prevent engine flywheel cooling without increasing the cost. The challenge is to provide a structure.

According to the present invention, a fly hole is fixed to an outer end portion of a crankshaft formed with a lubricating oil passage for supplying lubricating oil to a lubricated portion and projecting from a cylinder block, and a clutch disk of a clutch mechanism is connected to the flywheel. In the engine flywheel cooling structure arranged detachably,
A circulating oil passage for circulating the lubricating oil is formed in the flywheel,
The lubricating oil passage of the crankshaft is extended so as to communicate with the circulating oil passage.

  According to the flywheel cooling structure for an engine according to the present invention, the lubricating oil maintained at a substantially constant temperature is led from the lubricating oil passage of the crankshaft to the circulating oil passage of the flywheel and circulated in the flywheel. The flywheel can be reliably and stably cooled, and the clutch disk contacting the flywheel can be reliably and stably cooled. As a result, the wear of the clutch disk can be suppressed and the durability of the clutch disk can be improved. .

  In addition, since the lubricating oil can be circulated in the flywheel using the existing lubricating oil passage that supplies the lubricating oil to the lubricated part of the crankshaft, the cost is increased due to the provision of the flywheel cooling structure. Can be minimized.

Furthermore, it is not necessary to use an expensive material for countermeasures against heat damage for the clutch disk, which is advantageous in terms of cost.

It is a section side view of the flywheel cooling structure of the engine by Example 1 of the present invention. FIG. 2 is a sectional front view (II-II sectional view of FIG. 1) of the flywheel. FIG. 3 is a cross-sectional side view of the flywheel (a cross-sectional view taken along line III-III in FIG. 2).

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 3 are views for explaining a flywheel cooling structure for an automobile engine according to a first embodiment of the present invention.

  In the figure, reference numeral 1 denotes a crankshaft. The crankshaft 1 has a plurality of crankpin portions 1a that are offset from the shaft core and to which connecting rods are connected, and between the crankpin portions 1a and 1a and both end portions. The journal portion 1b is rotatably supported by a journal bearing 2. In addition, 1e is a balance weight integrally formed on the opposite side of the crank pin portion 1a.

The journal bearing 2 is formed in the cylinder block 3 and has a semicircular block side bearing portion 2a having a semicircular bearing metal 2c, and a semicircular bearing metal 2d which is detachably fastened to the semicircular block side bearing portion 2a. It is comprised with the circular bearing cap 2b. An oil pan 5 is connected to the lower surface of the cylinder block 3 and stores lubricating oil.

In the crankshaft 1, there is formed a lubricating oil passage 4 for supplying lubricating oil to the crankpin portion 1a and the journal portion 1b which are lubricated portions. The lubricating oil passage 4 includes a main oil passage 4a formed so as to pass through the crankpin portion 1a side from the axial center of the journal portion 1b, and the journal portion 1b and the crankpin portion 1a from the main oil passage 4a. A branch oil passage 4b that branches toward the outer peripheral surface is provided. One end of the main oil passage 4a is connected to an oil pump (not shown).

The outer end 1c of the crankshaft 1 is formed with a larger diameter than the journal 1b, and a projection 1d is formed on the outer end 1c. A part of the outer end 1 c and the protrusion 1 d are located in the clutch housing 6 coupled to the output side wall 3 a of the cylinder block 3. A clutch mechanism 8 is disposed in the clutch housing 6.

A thick disc-like flywheel 7 is coupled to the crankshaft 1 so as to contact the outer end 1c and the protrusion 1d. Specifically, the flywheel 7 is provided with a concave coupling hole 7b into which the projection 1d is fitted, and the end surface 1d 'of the projection 1d is in contact with the bottom surface 7b' of the coupling hole 7b. Further, an end surface 1c 'of the outer end 1c is in contact with a back surface 7c of the flywheel 7 located on the opposite side of the clutch mechanism 8. Reference numeral 7d denotes a starting ring gear coupled to the outer peripheral portion of the flywheel 7.

The clutch mechanism 8 includes a clutch disc 9 disposed so as to be able to contact and separate from the face surface 7a of the flywheel 7, and a pressing member attached to the flywheel 7 to press the clutch disc 9 against the face surface 7a. 10 and a release bearing 11 for releasing the pressure contact by the pressing member 10. The clutch disk 9 is splined to the input shaft 12a of the transmission mechanism 12 via a damper spring 9a. The pressing member 10 includes a pressure plate 10a that contacts the clutch disk 9, and a diaphragm spring 10b that presses the clutch disk 9 against the face surface 7a via the pressure plate 10a.

The flywheel 7 is formed with a circulating oil passage 13 for circulating lubricating oil, and an extended portion 4 a ′ of the main oil passage 4 a of the crankshaft 1 communicates with the circulating oil passage 13. The circulation oil passage 13 includes an introduction hole 13a for introducing lubricating oil, a circulation hole 13b for circulating the lubricating oil introduced from the introduction hole 13a, and a discharge hole for discharging the circulated lubricating oil onto the oil pan 5. 13c.

The introduction hole 13a opens at the bottom surface 7b 'of the coupling hole 7b and communicates with the extension 4a'. The discharge hole 13c opens in the back surface 7c and communicates with an oil hole 1f formed in an outer edge portion of the outer end portion 1c in the axial direction.

The circulation hole 13b is formed by a plurality of straight portions 13b 'formed so as to communicate with each other in a tangential direction from the outer peripheral surface of the flywheel 7. Reference numeral 13d denotes a seal screw that is screwed so as to close each of the straight portions 13b 'and the outer peripheral surface side portions of the introduction hole 13a and the discharge hole 13c.

  According to this embodiment, when the engine is rotated, the lubricating oil pumped from an oil pump (not shown) is supplied to each lubricated portion through the lubricating oil passage 4 and also passes through the extension portion 4a ′ of the main oil passage 4a. To the introduction hole 13a of the circulating oil passage 13 of the flywheel 7. The supplied lubricating oil circulates in the flywheel 7 through the circulation hole 13b, and is discharged onto the oil pan 5 from the discharge hole 13c through the oil hole 1f. Since the lubricating oil is maintained at a substantially constant temperature, for example, around 95 ° C., the flywheel 7 can be reliably and stably cooled. As a result, the clutch disk 9 abutting against the flywheel 7 can also be cooled reliably and stably. As a result, the wear of the clutch disk 9 can be suppressed and the durability of the clutch disk 9 can be improved.

  Further, since the lubricating oil can be circulated in the flywheel 7 using the existing lubricating oil passage 4 for supplying the lubricating oil to the lubricated portion such as the journal bearing 2 of the crankshaft 1, the flywheel 7 is cooled. High cost due to the provision of the structure can be minimized.

Furthermore, since it is not necessary to use an expensive material for countermeasures against heat damage for the clutch disk 9, this is also advantageous in terms of cost.

  Further, in the present embodiment, the plurality of linear portions 13b 'extending in the tangential direction are formed so as to communicate with each other, so that the circulating oil passage 13 that circulates in the disk-like flywheel 7 can be formed only by drilling with a drill.

1 Crankshaft 1a, 1b Crankpin part, journal part (lubricated part)
1c Outer end portion 3 Cylinder block 4 Lubricating oil passage 4a 'Extension portion 7 Flywheel 8 Clutch mechanism 9 Clutch disc 13 Circulating oil passage

Claims (1)

A flywheel is fixed to an outer end portion of the crankshaft formed with a lubricating oil passage for supplying lubricating oil to the lubricated portion and protrudes from the cylinder block. In the engine flywheel cooling structure,
A circulating oil passage for circulating the lubricating oil is formed in the flywheel,
A flywheel cooling structure for an engine, wherein the lubricating oil passage of the crankshaft is extended so as to communicate with the circulating oil passage.

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