JP2009115277A - Laminated connecting rod - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated connecting rod, inexpensively manufacturable with a simple structure, by sufficiently securing inner diameter accuracy of a bearing pressed in a large end part and a small end part, by thickening the thickness of the large end part and the small end part. <P>SOLUTION: A laminated part 2A having the large end part 2a, the small end part 2b and a rod part 2c, a laminated part 2B having the large end part 2a and a laminated part 2C having the small end part 2b are laminated. A projection 5 is arranged for projecting in the going in and out direction to the plane direction of the laminated parts by being molded by press working in an edge part being a part of the outer peripheral edge of the large end part 2a and the small end part 2b of the respective laminated parts 2A, 2B and 2C. A cutout 7 is arranged in a position corresponding to the projection 5 in the laminated part 2C unprovided with the projection 5. The mutual adjacent laminated parts are joined by meshing of the projection 5 and a recessed part 6 generated on a reverse surface of this projection 5 or meshing of the projection 5 and the cutout 7. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a laminated connecting rod formed by laminating a plurality of laminated parts.

  A connecting rod used for an engine is manufactured by forging, sintering, or constraining pressure forming from a steel bar or plate material. In addition, it may be formed by stamping by pressing a steel plate. When the connecting rod is manufactured by such forging or sintering, it is difficult to reduce the cost because of the large number of steps. On the other hand, plate-like laminated parts are laminated and integrated as a connecting rod that can be manufactured easily and inexpensively, avoids tilting of the bearings attached to the large and small ends, and improves bending strength and buckling strength. Laminated connecting rods fixed to the substrate have been proposed (for example, Patent Document 1 and Patent Document 2).

  The laminated connecting rod described in Patent Document 1 has a large end portion laminated as a set of laminated parts obtained by continuously punching the same material in order to suppress the dimensional variation between the laminated parts and reduce the manufacturing cost. The laminated parts are integrated with each other by press-fitting an annular part made of an outer ring of the bearing into a bearing fitting hole provided in the small end portion.

  In addition, the laminated connecting rod described in Patent Document 2 is a through-hole formed separately from the engagement between the coupling protrusion formed on the rod portion of the laminated component by press working and the recess formed on the back surface of the protrusion. Adjacent laminated parts are joined together by meshing with the holes.

Japanese Patent Laid-Open No. 2003-156028 JP 2004-324760 A

  Each of the above-mentioned conventional laminated connecting rods is obtained by laminating laminated parts of the same shape each having a large end portion, a small end portion, and a rod portion, and the same number of layers are laminated on the large end portion, the small end portion, and the rod portion. The members were laminated, and the thickness was uniform throughout. FIG. 7 shows a state in which such a laminated connecting rod is assembled to an engine. The laminated connecting rod 101 shown in the figure is obtained by laminating two laminated components 102 formed by press working.

  The large end portion 101a and the small end portion 101b of the laminated connecting rod 101 have bearing fitting holes 103 and 104, respectively. Bearings such as shell needle roller bearings 105 are press-fitted into the bearing fitting holes 103 and 104, respectively. The crank pin 106 and the piston pin 107 are supported by the bearings 105. The crankpin 106 is fixed in an eccentric state with respect to the crankshaft 108 between a pair of arms 109 that rotate integrally with the crankshaft 108. A balance weight 109 a is formed on a portion of each arm 109 opposite to the crankpin 106. The piston pin 107 is fixed to the piston 110.

  The pair of balance weights 109a are bulged inward in the axial direction as shown in the figure so that the overall axial dimension is not increased, so that the distance a between the opposing portions is relatively narrow. . In order to allow the laminated connecting rod 101 to pass through this narrow gap, it is necessary to reduce the thickness b of the rod portion 101c of the laminated connecting rod 101. However, in the case of the laminated connecting rod 101 having a uniform thickness throughout, if the thickness b of the rod portion 101c is reduced, the thickness of the large end portion 101a and the small end portion 101b is inevitably reduced. If the large end portion 101a and the small end portion 101b are thin, the width of the press-fit portion of the bearing 105 is insufficient, and the inner diameter accuracy of the bearing 105 may not be ensured. Further, the bearing 105 may come off. Therefore, the thickness b of the rod portion 101c cannot be made very thin, and the degree of freedom in design is small.

  The object of the present invention is to increase the thickness of the large end portion and the small end portion, sufficiently ensure the accuracy of the inner diameter of the bearing press-fitted into the large end portion and the small end portion, and can be manufactured inexpensively with a simple structure. It is to provide a laminated connecting rod.

  The laminated connecting rod of the present invention comprises a laminated component having a large end portion, a small end portion, and a rod portion, a laminated component having a large end portion, and a laminated component having a small end portion. A protrusion formed in the edge part which is a part of the outer peripheral edge of the end part and the small end part and protruding in the direction of entering and exiting the surface direction of the laminated component, and a recess generated on the back surface of the protrusion Adjacent laminated parts are joined together by meshing or meshing with a notch formed separately from the protrusion.

According to this configuration, in order to bond adjacent laminated parts to each other by engagement between the projections formed on the large end portion and the small end part of each laminated part and the recesses or notches, some laminated parts are A laminated part having only a large end portion or a small end portion and no rod portion can be obtained. As a result, the number of laminated parts in the rod part is reduced and the thickness of the rod part is reduced, while the number of laminated parts in the large end part and the small end part is increased and the thickness of the large end part and the small end part is increased. it can. If the thickness of the large end portion and the small end portion is large, it is possible to secure the inner diameter accuracy of the bearing by sufficiently securing the width of the press-fitting portion of the bearing that is press-fitted into the bearing fitting hole of the large end portion and the small end portion. it can. Also, the bearing can be prevented from coming off.
Since the protrusions, the recesses, and the notches are provided at the edge that is a part of the outer peripheral edge of the large end portion and the small end portion, the strength of the large end portion and the small end portion is hardly reduced. Therefore, it is not necessary to increase the diameters of the large end portion and the small end portion more than necessary. This laminated connecting rod has a simple structure in which a plurality of laminated parts are simply laminated, and the protrusions, recesses, and notches that connect adjacent laminated parts can be easily formed by pressing, so it is inexpensive. Can be manufactured.

  In the present invention, the laminated component may be formed by punching a steel plate into a predetermined shape. In that case, the laminated part having the protrusions is formed with respect to the steel plate as a raw material so that both side portions straddling the punching line of the punching process protrude in the direction of entering and exiting the surface direction of the laminated part. Then, it is good to shape | mold into a predetermined shape by the said punching process. In addition, the laminated part having the notch is formed by cutting the through hole serving as the notch so that both side portions straddling the punching line of the punching process are removed from the steel plate as the material, and then performing the punching process. It is good to mold into a predetermined shape.

  If the protrusion is formed as described above and then formed into a predetermined shape by punching, a portion of the protrusion that is outside the punching line is removed during the punching process, and the protrusion becomes compact. In addition, after forming the through hole to be a notch as described above, if the punching is formed into a predetermined shape, the through hole is divided at the position of the punching line, and the center side portion corresponds to the projection. It becomes a compact cutout. If the protrusion and the notch are compact, the strength reduction of the edge of the large end portion and the small end portion of the laminated component can be suppressed to a small level.

The protrusions and notches may be molded or formed at one or more locations on the edges of the large end portion and the small end portion of the laminated component, or may be molded or formed at multiple locations.
When the protrusions and notches are molded or formed at one or more locations on the large and small end portions, the adjacent laminated parts can be firmly bonded. When formed or formed at a plurality of locations, it is possible to bond more firmly.

The laminated part having the large end part, the small end part and the rod part is arranged in the middle, the laminated part having the large end part is arranged on both sides of the large end part of the laminated part, and both sides of the small end part are arranged. The laminated parts having the small end portions may be arranged on the laminated parts so that the laminated parts are laminated.
With this configuration, the rod portion is positioned at the center in the width direction of the large end portion and the small end portion, and the overall balance is good.

  The laminated connecting rod of the present invention comprises a laminated component having a large end portion, a small end portion, and a rod portion, a laminated component having a large end portion, and a laminated component having a small end portion. A protrusion formed in the edge part which is a part of the outer peripheral edge of the end part and the small end part and protruding in the direction of entering and exiting the surface direction of the laminated component, and a recess generated on the back surface of the protrusion Adjacent laminated parts are joined together by meshing or engaging with a notch formed separately from the above protrusions, so the large end portion and the small end portion are thick, and the large end portion and the small end portion are press-fitted. The inner diameter accuracy of the bearing can be ensured, and the bearing can be manufactured at a low cost with a simple structure.

  An embodiment of the present invention will be described with reference to FIGS. FIG. 1A is a perspective view showing an exploded state of a laminated connecting rod, and FIG. 1B is a perspective view showing an assembled state. The laminated connecting rod 1 is formed by laminating and integrating a plurality of plate-like laminated components 2 formed by processing steel plates. The plurality of laminated components 2 are composed of a laminated component 2A having a large end portion 2a, a small end portion 2b, and a rod portion 2c, a laminated component 2B having a large end portion 2a, and a laminated component 2C having a small end portion 2b. Become. For convenience of explanation, the laminated component 2A is a main laminated component, the laminated component 2B is a large-end laminated component, and the laminated component 2C is a small-end laminated component. A bearing fitting hole 3 through which a crank pin is inserted is provided in the large end portion 2a of each laminated component 2A, 2B, 2C, and a bearing fitting hole 4 through which a piston pin is inserted is provided in the small end portion 2b. Yes. In this embodiment, there are two main laminated components 2A, four large-end laminated components 2B and four small-end laminated components 2C, on both sides of the large end portion 2a of the two laminated main laminated components 2A. Two large-end laminated components 2B are arranged and laminated, and two small-end laminated components 2C are arranged and laminated on both sides of the small end portion 2b of the main laminated component 2A.

FIG. 2 is a cross-sectional view taken along a line II in FIG. Based on the coupling portion between the main laminated component 2A and the small end laminated component 2C shown in the figure, the coupling structure of the laminated components 2A, 2B, 2C will be described. The edge part which becomes a part of the outer peripheral edge of the small end portion 2b of each of the laminated parts 2A and 2C excluding the laminated part 2C arranged on the outermost side goes in and out with respect to the surface direction of the laminated parts 2A and 2C. A protrusion 5 protruding in the direction is provided. On the back surface of the protrusion 5, a recess 6 that is recessed in the same direction as the protrusion 5 is formed. Further, the edge of the small end portion 2b of the laminated component 2C disposed on the outermost side is cut at the same position in the circumferential direction as the projection 5, the length in the circumferential direction and the depth from the edge are the same dimension. A notch 7 is provided. Adjacent laminated parts 2A and 2C are coupled to each other by engaging the protrusions 5 and the recesses 6 of the adjacent laminated parts 2A and 2C, or the protrusions 5 and the notches 7 with each other. The joint portion of the main laminated component 2A and the large end laminated component 2B has the same structure (not shown).
As shown in FIGS. 1 and 5, the protrusions 5 and the notches 7 are provided at one or more locations in the circumferential direction of the large end portion 2a and the small end portion 2b, in this example, at three locations. Thus, if the protrusion 5 and the notch 7 are provided in one or more places on each of the large and small end portions, the adjacent laminated components 2A, 2B, 2C can be firmly bonded. When the protrusions 5 and the notches 7 are provided at three positions as in this example, the bonding can be more firmly performed.

  A method of manufacturing each of the laminated parts 2A, 2B, 2C will be described with reference to FIGS. As shown in FIG. 3, the laminated parts 2 </ b> A, 2 </ b> B, and 2 </ b> C are formed by punching a steel plate 10 as a material along a punching line 11 into a predetermined shape. However, prior to the punching process, the protrusion 5 and the notch 7 are formed. At that time, as shown in FIGS. 4 (A), (B), and (C), the protrusion 5 has both side portions straddling the punching line 11 in the surface direction of the steel plate 10, that is, the laminated parts 2A, 2B, and 2C. The original projection 8 is formed by pressing so as to protrude in the direction in and out of the surface direction. About the notch 7, as shown in FIG.4 (D), the through-hole 9 used as the notch 7 is formed by drilling so that the both sides which straddle the said punching line 11 may be removed. After processing the original projection 8 and the through hole 9, punching is performed along the punching line 11 to obtain the laminated components 2 </ b> A, 2 </ b> B, and 2 </ b> C. The protrusions 5 of the laminated parts 2A, 2B, and 2C obtained in this way are outside the punching line 11 with respect to the original protrusion 8 as shown in FIGS. 5 (A), (B), and (C). It becomes a compact one with parts removed. On the back side of the protrusion 5, a recess 6 is formed that is recessed in the same direction as the protrusion 5 protrudes. Further, the cutout 7 of the laminated parts 2B and 2C is a central portion of the through hole 9 divided at the position of the punching line 11 as shown in FIG. It becomes.

  The protrusion 5 and the notch 7 illustrated in the manufacturing method of FIGS. 3 to 5 are the original shape of the original protrusion 8 and the through hole 9 viewed from a direction orthogonal to the surface direction of the laminated components 2A, 2B, and 2C. The shape is a bowl shape that is long in the direction along the punching line 11 and semi-circular at both ends, but is not limited thereto. For example, the shapes of the original projection 8 and the through hole 9 viewed from the above direction may be triangular, quadrangular, circular, or other shapes.

  Laminate parts 2A, 2B, 2C manufactured by the above method are laminated in the predetermined arrangement, and the protrusions 5 and the recesses 6 and the protrusions 5 and the notches 7 are meshed with each other so that adjacent laminated parts are joined together. Thus, the laminated connecting rod 1 is completed. In the completed laminated connecting rod 1, since the large end portion 1a and the small end portion 1b are laminated with six laminated components, and the rod portion 1c is laminated with two laminated components, the large end portion 1a and the small end portion are laminated. The thickness of 1b is thick, and the thickness of the rod portion 1c is thin. The laminated connecting rod 1 has a simple structure in which a plurality of laminated parts 2A, 2B, and 2C are laminated, and the protrusion 5, the concave part 6, and the notch 7 that connect adjacent laminated parts are easily formed by pressing. Since it can be molded, it can be manufactured at low cost. Since the protrusion 5, the recess 6, and the notch 7 are provided at the edges of the large end portion 2a and the small end portion 2b of the laminated parts 2A, 2B, 2C, the strength of the large end portion 2a and the small end portion 2b is reduced. Almost no invitation. Therefore, it is not necessary to increase the diameters of the large end portion 2a and the small end portion 2b more than necessary.

  FIG. 6 shows a state where the laminated connecting rod 1 of the above embodiment is assembled to an engine. Since the configuration of the engine has already been described in the column of the problem to be solved by the invention, the description thereof is omitted here. In the laminated connecting rod 1 of the above embodiment, as described above, the large end portion 1a and the small end portion 1b are thick, and the rod portion 1c is thin. Therefore, the width of the press-fitting portion of the bearing 105 to be press-fitted into the bearing fitting holes 103 and 104 of the large end portion 1a and the small end portion 1b is sufficiently ensured, and the inner diameter accuracy of the bearing 105 is sufficiently secured, and the stacked connecting rod 1 is It is possible to prevent the bearing 105 from coming off. Further, since the rod portion 1c can pass even if the distance between the pair of balance weights 109a is narrow, the degree of freedom in design is high.

  In the above embodiment, the large connecting portion 1a and the small end portion 1b of the laminated connecting rod 1 have six laminated components 2A, 2B, and 2C laminated, and the rod portion 1c has a constitution in which two laminated components 2A are laminated. The number of laminated parts of each part can be changed as appropriate according to the specifications of the engine to be applied.

(A) is a perspective view which shows the decomposition | disassembly state of the lamination | stacking connecting rod concerning embodiment of this invention, (B) is a perspective view which shows the assembly state. It is sectional drawing of the II section of FIG. 1 (B). (A) is the figure which showed the processing position of the processus | protrusion on the steel plate used as a raw material, and the position of the punching line with the imaginary line, (B) is the enlarged view of the IIIB part. (A) is a figure which shows a part of steel plate which processed the protrusion, (B) is an enlarged view of the IVB part, (C) is IVC-IVC sectional drawing, (D) is sectional drawing of another steel plate. (A) is a view showing a part of a punched and formed laminated part, (B) is an enlarged view of the VB portion, (C) is a sectional view of the VC-VC, and (D) is a sectional view of another laminated part. It is. It is sectional drawing which shows the usage example of the laminated connecting rod. It is sectional drawing which shows the usage example of the conventional connecting rod.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Laminated connecting rod 1a ... Large end portion 1b of laminated connecting rod ... Small end portion 1c of laminated connecting rod ... Rod portion 2A of laminated connecting rod ... Main laminated component 2B ... Laminated component 2C for large end ... Laminated component 2a for small end ... Laminated component Large end portion 2b ... small end portion 2c of laminated component ... rod portion 5 of laminated component ... projection 6 ... concave 7 ... notch 10 ... steel plate 11 ... punching line

Claims (6)

  A laminated part having a large end part, a small end part, and a rod part, a laminated part having a large end part, and a laminated part having a small end part are laminated, and the large end part and the small end part of each laminated part are laminated. Engagement between the protrusion formed in the edge that becomes a part of the outer peripheral edge and protruding in the direction of entering and exiting the surface direction of the laminated component and the recess formed on the back surface of the protrusion, or the protrusion A laminated connecting rod, wherein adjacent laminated parts are joined together by meshing with a notch formed separately.   2. The laminated connecting rod according to claim 1, wherein the laminated component is formed by punching a steel plate into a predetermined shape.   3. The laminated part having the protrusions according to claim 2, wherein the protrusions are protruded in a direction in which both side portions straddling the punching line of the punching process come in and out with respect to the surface direction of the laminated part with respect to the steel plate as a material. A laminated connecting rod which is formed into a predetermined shape by the punching after being formed.   In claim 2, the laminated part having the notch, after processing the through-hole to be the notch so that both side portions straddling the punching line of the punching process is removed with respect to the steel plate as the material, A laminated connecting rod formed into a predetermined shape by punching.   5. The laminated connecting rod according to claim 1, wherein the protrusions and the notches are provided at a plurality of locations on the edges of the large end portion and the small end portion of the laminated component.   6. A laminated part having the large end part, the small end part, and the rod part is arranged in the middle, and the large end part is disposed on both sides of the large end part of the laminated part. And a laminated connecting rod in which the laminated components are laminated by arranging the laminated components having the small end portions on both sides of the small end portion.

Images