CN209781442U

CN209781442U - Connecting rod structure

Info

Publication number: CN209781442U
Application number: CN201822240748.5U
Authority: CN
Inventors: 渠娜; 刘涛; 刘俊杰; 张树旻; 尹吉; 杨乐; 刘君宇; 王文远; 钟德华
Original assignee: Great Wall Motor Co Ltd
Current assignee: Great Wall Motor Co Ltd
Priority date: 2018-12-28
Filing date: 2018-12-28
Publication date: 2019-12-13
Anticipated expiration: 2028-12-28

Abstract

The utility model provides a connecting rod structure, including shaft portion, and an organic whole link firmly in big head and little head at shaft portion both ends, it has big head hole and little head hole to locate to be constructed respectively in big head portion and little head, and the aperture in big head hole is greater than little head hole, in the footpath in big head hole, big head portion has the body that is located the inboard in order to form big head hole, and the ring body and be located the reinforcement in the outside, the reinforcement links to each other with shaft portion, and be formed with the recess on big head portion and at least one of the both sides terminal surface of big head hole axis quadrature, the recess is constructed in the junction of body and reinforcement and the setting of ring big head hole, and be formed with body terminal surface and reinforcement terminal surface respectively in the both sides of recess. The utility model discloses a connecting rod structure can improve its ability of resisting the deformation, and can avoid the great increase of connecting rod structure weight, and can overcome not enough among the prior art to there is better practicality.

Description

Connecting rod structure

Technical Field

The utility model relates to the technical field of engines, in particular to link structure that can be arranged in the variable compression ratio engine of multi-link formula.

Background

because of the non-adjustability of the crank-connecting rod mechanism, the piston stroke and the piston top dead center position are unchanged, namely the clearance volume Vc and the scavenging volume Vs of the engine are unchanged, and according to a compression ratio calculation formula, the compression ratio epsilon is (Vc + Vs)/Vc, so that the compression ratio of the engine is also unchanged, namely the compression ratio of the engine cannot be changed along with the load. However, the compression ratio should be determined as a compromise result of power performance, economy and combustion, which cannot be too large or too small, and at low speed and low load or partial load, if the compression ratio is too small, the combustible mixture cannot be sufficiently mixed, resulting in low combustion efficiency, high fuel consumption, and insufficient combustion emission, whereas at high speed and high load, if the compression ratio of the engine is too large, knocking is easily generated, and if the compression ratio is light, the power output is affected, and if the compression ratio is heavy, the engine parts are damaged.

The multi-connecting rod type variable compression ratio is the only engine technology which achieves the condition of mass production, and the compression ratio of the engine is changed by continuously changing the top dead center position of the piston of the engine so as to meet the requirements of different engine loads and enable the engine to work in the best working area all the time, so that the dynamic property of the engine can be improved, the oil consumption can be reduced, the emission can be reduced, and the contradiction between the dynamic property, the economical efficiency and the emission can be well solved.

In the existing multi-connecting rod type variable compression ratio mechanism, a driving connecting rod connected with an eccentric shaft for regulating and controlling the compression ratio is stressed to be tensile stress, and the magnitude of the tensile stress is generally equal to the gas pressure of an engine, so that the deformation of a large end part of the driving connecting rod is large in work, the bearing bush is easy to wear, and a larger size needs to be designed to overcome the deformation of the large end part. However, the increase of the size of the large head of the driving connecting rod also leads to a larger weight increase, so that the inertia force is increased, and the operation reliability of the multi-connecting-rod mechanism is not ensured.

SUMMERY OF THE UTILITY MODEL

In view of this, the present invention is directed to a connecting rod structure, so as to improve the deformation resistance of the connecting rod big end hole position and avoid the great increase of the weight of the connecting rod.

In order to achieve the above purpose, the technical scheme of the utility model is realized like this:

A connecting rod structure comprises a rod body part, a large head part and a small head part which are integrally and fixedly connected to two ends of the rod body part, wherein a large head hole and a small head hole are respectively formed in the large head part and the small head part, the diameter of the large head hole is larger than that of the small head hole, the large head part is provided with a body which is positioned on the inner side to form the large head hole and a reinforcing body which surrounds the body and is positioned on the outer side, the reinforcing body is connected with the rod body part, a groove is formed in at least one of two side end faces of the large head part, which are orthogonal to the axis of the large head hole, the groove is formed in the connecting position of the body and the reinforcing body and is arranged around the large head hole, and a body end face and a reinforcing body end face are respectively formed on two sides of the groove.

Furthermore, the grooves are formed on the end surfaces of the two sides of the big head part, which are orthogonal to the axis of the big head hole.

Further, two opposite side end faces of the rod body part, which are orthogonal to the axis of the big head hole, are provided with a middle end face which is parallel to the reinforcement end face of the corresponding side, and an end face which is positioned between the middle end face and the reinforcement end face; the height of the middle end surface along the axial direction of the big head hole is smaller than that of the reinforcement body end surface, and the height of the end surface along the axial direction of the big head hole is gradually increased and is flush with the reinforcement body end surface along the direction of the reinforcement body end surface.

Furthermore, the end face of the reinforcing body is 4-5mm higher than the end face of the middle part.

Furthermore, convex ribs or notches are formed on two opposite side end faces of the rod body part, which are orthogonal to the axis of the big-end hole, so that the cross section of the rod body part is in a cross shape or an I shape, and the middle end face and the end face of each side are respectively arranged on two sides of the convex ribs or notches on the side.

Further, the height of the end face of the reinforcing body along the axial direction of the big head hole is smaller than that of the end face of the body.

Further, the groove is formed by splicing arc surfaces respectively connected with the body end surface and the reinforcement end surface on two sides, the splicing point of the arc surfaces on two sides is positioned at the bottom of the groove, and the common tangent line of the arc surfaces on two sides of the splicing point is parallel to the middle end surface.

Further, in the axial direction of the large-head hole, the height of the end face of the reinforcing body on one side close to the shaft part is smaller than the height of the other side opposite to the shaft part.

further, the width of the end face of the body is smaller than that of the end face of the reinforcement body along the radial direction of the large head hole.

Further, the width of the end face of the body is between 2 and 3.5mm, and the width of the end face of the reinforcing body is between 3 and 5mm along the radial direction of the big head hole.

Compared with the prior art, the utility model discloses following advantage has:

(1) Connecting rod structure through set up the rigidity of the multiplicable connecting rod major part position of rib to improve its ability of resisting the deformation, and can realize again through the setting of recess and subtract heavy, can avoid the great increase of connecting rod structure weight, and can overcome not enough among the prior art, so that this connecting rod structure has better practicality.

(2) the grooves are formed in the two sides, so that the section of the large head part is in an I shape, the large head part has good deformation resistance, and the weight reduction effect is good.

(3) The transition from the middle end face to the end face of the reinforcing body is carried out through the end faces, so that the stress conduction can be facilitated, and the stress deformation can be reduced.

(4) The cross section of the rod body part is I-shaped, so that the rod body part has better rigidity and can be beneficial to light weight.

(5) The end face of the body is higher than the end face of the reinforcing body, so that the rigidity of the position of the big end hole can be increased.

(6) The groove is an arc groove, and the common tangent of the arc grooves at the two sides is parallel to the end surface of the middle part, so that the external force applied to the large head part can be favorably transmitted outwards, and the deformation of the large head hole is reduced.

(7) The two sides of the end surface of the reinforcing body have different heights, so that the rigidity of the side with larger stress of the big end hole can be improved, and the stress deformation of the big end hole is reduced.

(8) the width of the end face of the body is smaller than that of the end face of the reinforcement body, so that stress in the large head hole can be dispersed, and stress deformation of the large head hole is further reduced.

drawings

The accompanying drawings, which form a part hereof, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without undue limitation. In the drawings:

Fig. 1 is a schematic structural diagram of a connecting rod structure according to an embodiment of the present invention;

3 FIG. 3 2 3 is 3 a 3 schematic 3 view 3 of 3 the 3 structure 3 of 3 section 3 A 3- 3 A 3 in 3 FIG. 31 3; 3

Description of reference numerals:

1-rod body, 2-big head, 3-small head and 4-bearing bush;

101-convex rib, 102-middle end face and 103-end face;

201-big head hole, 202-groove, 203-body, 204-reinforcement;

2021-arc surface, 2031-body end surface, 2041-reinforcement end surface;

301-small head hole;

401-oil groove.

Detailed Description

It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict.

the present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

The present invention relates to a connecting rod structure, which is generally applied to a multi-connecting rod type variable compression ratio engine, and is specifically used as a driving connecting rod connected with an eccentric shaft for regulating and controlling the compression ratio, so that when the eccentric shaft is controlled to rotate, the driving connecting rod can be linked with other connecting rods connected in a hinged manner through the connecting rod structure, and further, the change of a top dead center of a piston is realized, so as to complete the adjustment of the compression ratio of the engine.

Specifically, as shown in fig. 1 in combination with fig. 2, the connecting rod structure of this embodiment includes a rod body portion 1, a large head portion 2 and a small head portion 3 integrally connected to two ends of the rod body portion 1, and a large head hole 201 and a small head hole 301 are respectively formed at the large head portion 2 and the small head portion 3, and the diameter of the large head hole 201 is larger than that of the small head hole 301.

Further, in the radial direction of the large-headed hole 201 in the present embodiment, the large-headed portion 2 at one end also has a body 203 on the inner side to form the above-described large-headed hole 201, and a reinforcing body 204 on the outer side of the ring body 203. The reinforcement body 204 realizes connection between the whole big head 2 and the shaft body 1, and grooves 202 are formed on both side end faces of the big head 2 orthogonal to the axis of the big head hole 201, the grooves 202 are specifically located at the connection position of the body 203 and the reinforcement body 204, and the grooves 202 are also arranged in a ring shape around the big head hole 201. By the arrangement of the groove 204, a body end surface 2031 corresponding to the body 203 and a reinforcement end surface 2041 corresponding to the reinforcement 204 are formed on both side end surfaces of the large head 2 and also on both sides of the groove 202, respectively.

In the present embodiment, corresponding to the body end surface 2031 and the reinforcement end surface 2041 formed on the end surfaces on both sides of the large end portion 2, especially the reinforcement end surface 2041 close to the shaft portion 1, the shaft portion 1 has a middle end surface 102 arranged in parallel with the reinforcement end surface 2041 on the corresponding side and an end surface 103 located between the middle end surface 102 and the reinforcement end surface 2041 on the two opposite side end surfaces orthogonal to the axis of the large end hole 201. In addition, in order to improve the structural rigidity of the shaft body 1, in this embodiment, the two opposite side end surfaces of the shaft body 1, which are orthogonal to the axis of the large-head hole 201, that is, the two side end surfaces having the middle end surface 102 and the end surface 103, are also respectively configured with the convex rib 101, the arrangement of the convex rib 101 makes the cross section of the shaft body 1 be in a cross shape with better deformation resistance, and the middle end surface 102 and the end surface 103 of each side are also respectively disposed on two sides of the convex rib 101 of the corresponding side.

of course, in the present embodiment, in addition to the cross-shaped cross-section of the shaft portion 1, the rib 101 may be configured as a notch, so that the cross-section of the shaft portion 1 is configured as a conventional i-shaped cross-section, thereby providing a better strength to the shaft portion 1. It should be noted that, instead of being cross-shaped or i-shaped, the shaft body portion 1 may have a generally rectangular cross-section. In this embodiment, for the middle end surface 102 and the end surface 103, the height of the middle end surface 102 along the axial direction of the big head hole 201 is smaller than that of the reinforcement end surface 2041, however, in order to facilitate the transmission of force between the big head 2 and the shaft 1, the height of the end surface 103 along the axial direction of the big head hole 201 is gradually increased along the direction of the reinforcement end surface 2041 until the end surface 103 is flush with the reinforcement end surface 2041.

In this embodiment, as a possible implementation structure, the end surface 2041 of the reinforcement body at the large end 2 may be 4-5mm higher than the middle end surface at the rod body 1 at the same side, and may be specifically 4mm, 4.2mm, 4.5mm, 4.6mm, 4.8mm or 5mm higher. In order to ensure the rigidity of the big-end hole 201, the height of the reinforcement end surface 2041 along the axial direction of the big-end hole 201 is smaller than the height of the body end surface 2031 in the present embodiment, where the height difference h between the body end surface 2031 and the reinforcement end surface 2041 can be flexibly selected according to the design requirement in the actual implementation, which is not limited in the present embodiment.

In order to facilitate the transmission of the external force from the large head 2 to the shaft body 1 to reduce the stress deformation of the large head hole 201, in this embodiment, as a preferred structural form, the groove 202 is formed by splicing the arc surfaces 2021 respectively connected to the body end surface 2031 and the reinforcement end surface 2041 on both sides, so as to achieve the smooth transition between the body end surface 2031 and the reinforcement end surface 2041 on both sides by the connection of the arc surfaces 2021 on both sides. The joint point of the arc surfaces 2021 at both sides is located at the bottom of the groove 202, and the common tangent line Q of the arc surfaces 202 at both sides at the joint point is also parallel to the middle end face 102 on the shaft body 1.

It should be noted in this embodiment that, in the operation of the multi-link variable compression ratio engine, for the drive link constituted by the link structure of this embodiment, the force applied to the side close to the end portion at the large end portion 2 is greater than the force applied to the side close to the shaft portion 1. Therefore, in order to increase the rigidity of the side of the big-end hole 201 that is subjected to a larger force, so as to reduce the deformation of the big-end hole 201, in this embodiment, the height of the reinforcement end surface 2041 close to the shaft portion 1 is smaller than the height of the other side opposite to the shaft portion 1, that is, the height of the end portion of the whole connecting rod structure, along the axial direction of the big-end hole 201.

In addition, in addition to the above dimension designs along the axial direction of the large-head hole 201, in the radial direction of the large-head hole 201, the width d of the body end surface 2031 is smaller than the width K of the reinforcement end surface 2041. Moreover, in particular implementations, such as in a radial direction of the large-head hole 201, the width d of the body end surface 2031 can be between 2mm and 3.5mm, and can be, in particular, 2mm, 2.2mm, 2.5mm, 2.65mm, 2.7mm, 2.9mm, or 2.95mm, while the width k of the reinforcement end surface 2041 can be between 3mm and 5mm, and can be, in particular, 3mm, 3.2mm, 3.5mm, 4mm, 4.3mm, 4.5mm, 4.8mm, or 5 mm.

It should be noted that, in the present embodiment, in addition to the above-described respective related structures at the large head portion 2, it is of course possible to provide the same structure at the small head portion 3, so as to also increase the resistance to deformation at the position of the large head hole 301. In practical use, the bearing bush 4 can be pressed in the big-end hole 201, and the inner wall of the bearing bush 4 is provided with the oil groove 401, so as to realize effective lubrication between the big-end hole 201 and the eccentric shaft.

The connecting rod structure of the embodiment can enable the cross section of the big head part 2 to be in an I shape through the arrangement of the reinforcing body 204 and the groove 202, so that the rigidity of the position of the big head part 2 of the connecting rod can be increased, the deformation resistance of the connecting rod can be improved, meanwhile, the weight reduction is realized through the arrangement of the groove 202, the great increase of the weight of the connecting rod structure can be avoided, the defects in the prior art can be overcome, and the connecting rod structure has better practicability.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a connecting rod structure, includes shaft portion (1), and an organic whole link firmly in big head (2) and little head (3) at shaft portion (1) both ends, in big head (2) with little head (3) department is constructed big head hole (201) and little head hole (301) respectively, just the aperture in big head hole (201) is greater than little head hole (301), its characterized in that: in the radial direction of the big head hole (201), the big head (2) is provided with a body (203) which is positioned at the inner side to form the big head hole (201), and a reinforcing body (204) which is positioned at the outer side and surrounds the body (203), the reinforcing body (204) is connected with the rod body part (1), a groove (202) is formed on at least one of two side end surfaces of the big head (2) which are orthogonal to the axis of the big head hole (201), the groove (202) is formed at the connecting position of the body (203) and the reinforcing body (204) and is arranged around the big head hole (201), and a body end surface (2031) and a reinforcing body end surface (2041) are respectively formed on two sides of the groove (202).

2. the connecting rod structure as set forth in claim 1, wherein: the grooves (202) are formed in the end faces of the large head (2) on two sides orthogonal to the axis of the large head hole (201).

3. the link structure according to claim 2, wherein: the two opposite side end faces of the rod body part (1) orthogonal to the axis of the big head hole (201) are provided with a middle end face (102) parallel to the reinforcement end face (2041) on the corresponding side and an end face (103) positioned between the middle end face (102) and the reinforcement end face (2041); the height of the middle end surface (102) along the axial direction of the big head hole (201) is smaller than that of the reinforcement body end surface (2041), and along the direction of the reinforcement body end surface (2041), the height of the end surface (103) along the axial direction of the big head hole (201) is gradually increased to be flush with the reinforcement body end surface (2041).

4. The link structure according to claim 3, wherein: the end face (2041) of the reinforcing body is 4-5mm higher than the end face (102) of the middle part.

5. The link structure according to claim 3, wherein: convex ribs (101) or notches are formed in two opposite side end faces of the rod body part (1) which are orthogonal to the axis of the big head hole (201), so that the cross section of the rod body part (1) is in a cross shape or an I shape, and the middle end face (102) and the end face (103) of each side are arranged on two sides of the convex ribs (101) or the notches of the side.

6. The link structure according to any one of claims 3 to 5, wherein: the height of the reinforcement body end surface (2041) in the axial direction of the big head hole (201) is smaller than that of the body end surface (2031).

7. The link structure according to claim 6, wherein: the groove (202) is formed by splicing arc surfaces (2021) respectively connected with the body end surface (2031) and the reinforcement body end surface (2041) at two sides, the splicing point of the arc surfaces (2021) at two sides is positioned at the bottom of the groove (202), and the common tangent line of the arc surfaces (2021) at two sides of the splicing point is parallel to the middle end surface (102).

8. the link structure according to claim 6, wherein: the height of the reinforcement body end surface (2041) close to the shaft part (1) is smaller than the height of the other side opposite to the shaft part (1) along the axial direction of the large head hole (201).

9. The connecting rod structure as set forth in claim 1, wherein: the body end surface (2031) has a smaller width than the reinforcement end surface (2041) in the radial direction of the large-head hole (201).

10. The link structure of claim 9, wherein: the width of the body end surface (2031) is between 2 and 3.5mm and the width of the reinforcement body end surface (2041) is between 3 and 5mm in the radial direction of the big head hole (201).