JP2009058090A - Built-up type crankshaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plastic fastening part mutually fastening divided pieces, enhanced against coming off. <P>SOLUTION: A built-up type crankshaft 1 is built up as one body by mutually assembling a plurality of divided pieces 2A-2I by the plastic fastening parts 3. The plastic fastening part 3 includes building hole parts 8 formed on one sides of the adjacent divided pieces 2A-2I, and building shaft parts 6 formed on other sides. Plastic fastening is carried out by pressing the building shaft part 6 into the building hole part and assembling the same. Oil holes 10, 11 are formed on the divided pieces 2A-2I over insides of the building shaft parts 6. Communication holes 14, 15 are formed with passing through the building hole part 8 and the building shaft part 6 in order to keep communication between the oil holes 10, 11 of the adjacent divided pieces 2A-2I. Hollow pins 16, 17 are inserted in the communication holes 14, 15. Communication between the oil holes 10, 11 of the adjacent divided pieces 2A-2I is kept through hollow parts 16a, 17a and lateral holes 16b, 17b of the hollow pins 16, 17. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an engine crankshaft, and more particularly to an assembly-type crankshaft formed by assembling a plurality of divided pieces integrally.

  Conventionally, as this type of technology, for example, a crankshaft described in Patent Document 1 below can be cited. This crankshaft is constituted by connecting a connecting rod support shaft, a crank neck shaft, a basic neck shaft and a main support neck shaft by fitting them together at a plastic fastening portion. Inside the crankshaft, an oil hole is formed through which lubricating oil similar to that of the integrated crankshaft flows.

Japanese Patent No. 2807761

  However, in the crankshaft described in Patent Document 1, since the plurality of divided pieces are only assembled by fitting at the plastic fastening portion, insufficient strength of the plastic fastening portion becomes a problem. That is, when the piston's kinetic force acts on the crankshaft during engine operation, a force is applied in a direction in which the plastic fastening portion is unmated, and the plastic fastening portion is weak against the removal.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an assembly-type crankshaft that can strengthen a plastic fastening portion that fastens divided pieces against each other. is there.

  In order to achieve the above object, an invention according to claim 1 is an assembly type crankshaft in which a plurality of divided pieces are assembled together by a plastic fastening portion, and the plastic fastening portions are adjacent to each other. Including an assembled hole portion formed on one of the divided pieces and an assembled shaft portion formed on the other of the adjacent divided pieces, and being plastically fastened by press-fitting the assembled shaft portion into the assembled hole portion. In order to communicate between the oil holes formed in each of the divided pieces over the interior of the assembled shaft portion and the oil holes of the adjacent divided pieces, the formed holes are formed through the assembled hole portion and the assembled shaft portion of the plastic fastening portion. A communicating hole, a hollow pin inserted into the communicating hole, and a lateral hole formed on the outer periphery of the hollow pin, and the oil holes of adjacent divided pieces communicate with each other via the hollow hole and the lateral hole of the hollow pin. The intent is that

  According to the configuration of the above invention, the communication hole is formed through the assembly hole portion and the assembly shaft portion of the plastic fastening portion, and the hollow pin is inserted into the communication hole, so that the hollow pin functions as a retainer. In addition, it is possible to prevent the assembled shaft portion from coming off from the assembled hole portion. Moreover, since the oil holes of adjacent divided pieces communicate with each other via the hollow and lateral holes of the hollow pins, the oil holes of all the divided pieces communicate with each other.

  In order to achieve the above-mentioned object, the invention according to claim 2 is characterized in that, in the invention according to claim 1, the communication hole intersects at right angles to the oil hole.

  According to the configuration of the invention described above, in addition to the operation of the invention according to claim 1, since the communication hole is not processed obliquely with respect to the oil hole, generation of burrs due to processing is suppressed.

  According to the first aspect of the present invention, the plastic fastening portion that fastens the divided pieces to each other can be made strong against disconnection, and thereby the fastening strength of the plastic fastening portion can be improved.

  According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, it is possible to prevent seizure of the assembled crankshaft due to the burr foreign material during use in the engine.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment embodying an assembly type crankshaft of the present invention will be described in detail with reference to the drawings. In this embodiment, the present invention will be described in the form of an assembly type crankshaft for a four-cylinder engine.

  FIG. 1 is a side view of an assembled crankshaft 1 according to this embodiment. This assembly type crankshaft 1 is configured by assembling nine divided pieces 2A, 2B, 2C, 2D, 2E, 2F, 2G, 2H, and 2I together by a plastic fastening portion 3 and assembling them integrally. In FIG. 1, the first divided piece 2A, the third divided piece 2C, the fifth divided piece 2E, and the seventh divided piece 2G have the same shape as each other from the left side, and have a thick plate-like counterweight portion 4 and a columnar shape. A journal unit 5; The journal portion 5 is disposed corresponding to the substantially central portion of the counterweight portion 4. A shaft assembly 6 projects from the center of the tip of the journal section 5. A serration 7 is formed on the outer periphery of the assembled shaft portion 6. The serrations 7 extend in the axial direction of the assembled shaft portion 6 and are composed of alternating peaks and valleys. An assembled hole portion 8 is formed at a position near one end of the counterweight 4.

  In FIG. 1, the second divided piece 2B, the fourth divided piece 2D, the sixth divided piece 2F, and the eighth divided piece 2H have the same shape from the left side, and have a thick plate-like counterweight portion 4 and a pin portion 20. With. The pin portion 20 is disposed corresponding to a position near one end of the counterweight portion 4. The shaft assembly 6 projects from the center of the tip of the pin 20. Serrations (not shown) are formed on the outer periphery of the assembled shaft portion 6 in the same manner as described above. An assembled hole portion 8 is formed in the central portion of the counterweight portion 4.

  In FIG. 1, the ninth divided piece 2I at the right end has a different shape from the other divided pieces 2A to 2H. The ninth divided piece 2 </ b> I includes a journal portion 5, a combined shaft portion 6 formed at the center of the tip of the journal portion 5, and a flange portion 9 formed at the other end of the journal portion 5. Serrations (not shown) are formed on the outer periphery of the assembled shaft portion 6 in the same manner as described above.

  In this embodiment, each plastic fastening portion 3 includes an assembled hole portion 8 formed in one of the adjacent divided pieces 2A to 2H, and an assembled shaft portion 6 formed in the other of the adjacent divided pieces 2A to 2I. including. Each plastic fastening part 3 is plastically fastened by press fitting the assembled shaft part 6 into the assembled hole part 8 and assembling it.

  2 and 3, as an example, an assembly process of the first divided piece 2A and the second divided piece 2B is shown in a side view. The assembly of both divided pieces 2A and 2B is performed by press-fitting the assembled shaft portion 6 of the second divided piece 2B into the assembled hole portion 8 of the first divided piece 2A. At the time of this press-fitting, the meat on the inner wall of the assembly hole portion 8 is compressed by the crest portion of the serration 7 of the assembly shaft portion 6 and enters the trough portion of the serration 7. In this way, the inner wall of the assembled hole portion 8 is deformed by plastic flow and engaged with the serration 7 of the assembled shaft portion 6, whereby the assembled hole portion 8 and the assembled shaft portion 6 are firmly plastically fastened. ing. The assembly of the third divided piece 2C to the ninth divided piece 2I is the same as described above.

  This assembly type crankshaft 1 has an oil passage for supplying lubricating oil to each journal part 5 and each pin part 20. In FIG. 4, the 1st-3rd division | segmentation piece 2A-2C just after an assembly | attachment is shown with sectional drawing. In each of the divided pieces 2 </ b> A to 2 </ b> C, oil holes 10 and 11 are formed in advance over the interior of the assembled shaft portion 6 and the journal portion 5 or the pin portion 20. One end of each oil hole 10, 11 is closed, and the other end is opened to the outside. The opening is sealed with a plug 12. Each journal portion 5 and each pin portion 20 is formed with a branch hole 13 branched from the oil holes 10 and 11. The lubricating oil supplied to the oil holes 10 and 11 is supplied to the outer periphery of the journal part 5 and the pin part 20 through the branch hole 13. In order to allow the oil holes 10 and 11 of the adjacent divided pieces 2A to 2C to communicate with each other, the counter weight portion 4 of each of the divided pieces 2A to 2C includes the assembled hole portion 8 and the assembled shaft portion 6 of the plastic fastening portion 3. The communication holes 14 and 15 penetrating through are formed. Each communication hole 14, 15 is configured by aligning a hole formed in the counterweight portion 4 and a hole formed in the assembled shaft portion 6 in a straight line. The communication holes 14 and 15 are formed so as to intersect at right angles to the oil holes 10 and 11.

  In this embodiment, a hollow pin is disposed in each of the communication holes 14 and 15. FIG. 5 is a sectional view showing the first to third divided pieces 2A to 2C in a state where the hollow pins 16 and 17 are disposed in the communication holes 14 and 15, respectively. Hollow pins 16 and 17 are inserted into the communication holes 14 and 15 from the outside of the counterweight portion 4. That is, the first hollow pin 16 is inserted into the communication hole 14 between the first and second divided pieces 2A and 2B, and the communication hole between the second and third divided pieces 2B and 2C. 15, a second hollow pin 17 is inserted and arranged. As an example, the first hollow pin 16 is shown in a perspective view in FIG. As shown in FIGS. 5 and 6, the hollow pins 16 and 17 have hollows 16a and 17a, and lateral holes 16b and 17b communicating with the hollows 16a and 17a are formed on the outer circumferences of the hollow pins 16 and 17, respectively. Is done. The hollows 16 a and 17 a are opened at both ends of the hollow pins 16 and 17. The horizontal holes 16b and 17b are positioned so as to open into the corresponding oil holes 10 and 11 in a state where the hollow pins 16 and 17 are disposed in the communication holes 14 and 15, respectively. Thereby, as shown in FIG. 5, between the oil holes 10 and 11 of the adjacent divided pieces 2A to 2C communicate with each other through the hollows 16a and 17a of the hollow pins 16 and 17 and the lateral holes 16b and 17b. ing. Of each of the hollow pins 16 and 17, the opening portion that opens to the outside is closed by a plug 18. About the other 3rd-9th division | segmentation piece 2C-2I, about the structure regarding an oil hole, a communicating hole, and a hollow pin, it is the same as that of the above, and description is abbreviate | omitted.

  For example, for each of the divided pieces 2A to 2I, a forged product such as S45C or S35C containing an appropriate amount of carbon can be used. Further, as an example, a hardened product such as S45C or S35C having high hardness can be used for the hollow pins 16 and 17.

  According to the structure of the assembly type crankshaft 1 of this embodiment described above, each of the divided pieces 2A to 2I is fastened by the plastic fastening portion 3 including the paired shaft portion 6 having the serration 7 on the outer periphery and the paired hole portion 8. Therefore, the fastening strength with respect to the torsional load of each plastic fastening part 3 can be improved. In addition, communication holes 14 and 15 are formed through the assembly hole portion 8 and the assembly shaft portion 6 of each plastic fastening portion 3, and the hollow pins 16 and 17 are inserted into the communication holes 14 and 15. . Accordingly, the hollow pins 16 and 17 function as a stopper, and the assembled shaft portion 6 is prevented from coming off from the assembled hole portion 8. As a result, the plastic fastening portion 3 that fastens the divided pieces 2 </ b> A to 2 </ b> I can be made strong against disconnection, and thereby the fastening strength of the plastic fastening portion 3 can be improved. Therefore, when the assembly type crankshaft 1 is used in an engine, the kinetic force of the piston acts on each journal portion 5 and each pin portion 20 of the assembly type crankshaft 1 during operation of the engine, and each plastic fastening portion. Even if force is applied in the direction in which the fastening of 3 is released, the firm fastening state of each plastic fastening portion 3 can be maintained.

  In this embodiment, the oil holes 10 and 11 of the adjacent divided pieces 2A to 2I communicate with each other through the hollows 16a and 17a of the hollow pins 16 and 17 and the lateral holes 16b and 17b. Accordingly, the oil holes 10 and 11 of all the divided pieces 2 </ b> A to 2 </ b> I communicate with each other, and the lubricating oil can be distributed between all the oil holes 10 and 11. As a result, lubricating oil can be supplied to each journal part 5 and each pin part 20, and the lubrication performance requested | required of each journal part 5 and each pin part 20 can be ensured.

  In this embodiment, the communication holes 14 and 15 are formed so as to intersect at right angles to the oil holes 10 and 11. Therefore, since the communication holes 14 and 15 are not processed obliquely with respect to the oil holes 10 and 11, generation of burrs due to the processing is suppressed. For this reason, when the assembly-type crankshaft 1 is used for an engine, the burr foreign matter is not mixed with the lubricating oil and does not flow to the journal portion 5 and the pin portion 20, and the journal portion 5 and the pin portion 20 are seized by the burr foreign matter. Can be prevented.

  In addition, this invention is not limited to the said embodiment, A part of structure can also be changed suitably and implemented in the range which does not deviate from the meaning of invention.

  For example, in the above-described embodiment, the present invention is embodied in the assembly-type crankshaft 1 for a four-cylinder engine. However, the present invention is embodied in an assembly-type crankshaft for an engine having a number of cylinders other than four cylinders. You can also.

The side view which shows an assembly-type crankshaft. The side view which shows the assembly | attachment process of a 1st division piece and a 2nd division piece. The side view which shows the assembly | attachment process of a 1st division piece and a 2nd division piece. Sectional drawing which shows the 1st-3rd division | segmentation piece immediately after an assembly | attachment. Sectional drawing which shows the 1st-3rd division | segmentation piece which has arrange | positioned the hollow pin in the communicating hole. The perspective view which shows a 1st hollow pin.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Assembling-type crankshaft 2A 1st division piece 2B 2nd division piece 2C 3rd division piece 2D 4th division piece 2E 5th division piece 2F 6th division piece 2G 7th division piece 2H 8th division piece 2I 9th division piece 3 Plastic fastening portion 6 Assembly shaft portion 8 Assembly hole portion 10 Oil hole 11 Oil hole 14 Communication hole 15 Communication hole 16 First hollow pin 16a Hollow 16b Horizontal hole 17 Second hollow pin 17a Hollow 17b Horizontal hole

Claims (2)

An assembly-type crankshaft in which a plurality of divided pieces are assembled together by assembling together at a plastic fastening portion,
The plastic fastening portion includes an assembled hole portion formed in one of adjacent divided pieces and an assembled shaft portion formed in the other of the adjacent divided pieces, and press-fits the assembled shaft portion into the assembled hole portion. And being assembled by plastic fastening,
An oil hole formed over the interior of each of the divided shaft portions in each of the divided pieces;
A communication hole formed through the assembly hole portion and the assembly shaft portion of the plastic fastening portion in order to communicate between the oil holes of the adjacent divided pieces;
A hollow pin inserted into the communication hole;
An assembly type crank comprising a lateral hole formed on an outer periphery of the hollow pin, and the oil holes of the adjacent divided pieces are communicated with each other through the hollow of the hollow pin and the lateral hole. shaft. The assembly type crankshaft according to claim 1, wherein the communication hole intersects the oil hole at a right angle.

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