CN216811945U

CN216811945U - Piston and engine

Info

Publication number: CN216811945U
Application number: CN202122981541.5U
Authority: CN
Inventors: 王经; 李成艳; 焦明裕; 乔芳; 王凝露
Original assignee: Weichai Power Co Ltd; Weichai Heavy Machinery Co Ltd
Current assignee: Weichai Power Co Ltd; Weichai Heavy Machinery Co Ltd
Priority date: 2021-11-30
Filing date: 2021-11-30
Publication date: 2022-06-24
Anticipated expiration: 2031-11-30

Abstract

The utility model belongs to the technical field of engines, and discloses a piston and an engine, wherein the piston comprises a piston body and a combustion chamber arranged at the head of the piston body, the radial section of the combustion chamber is of a special-shaped structure, an inner cooling oil duct is arranged inside the piston body and is annularly arranged between the outer wall of the piston body and the combustion chamber, the radial section of the inner cooling oil duct is of a special shape, and the circumferential inner contour of the inner cooling oil duct corresponds to the circumferential contour of the combustion chamber. The piston provided by the utility model is provided with the inner cooling oil channel matched with the circumferential profile of the special-shaped combustion chamber, so that the cooling distances between the top surface of the piston at the asymmetric part of the special-shaped combustion chamber, the throat of the piston and the inner cooling oil channel are reduced, the cooling effect of the top surface of the piston at the asymmetric part of the special-shaped combustion chamber and the throat of the piston is improved, and the service life of the piston is further prolonged.

Description

Piston and engine

Technical Field

The utility model belongs to the technical field of engines, and particularly relates to a piston and an engine.

Background

This section provides background information related to the present disclosure only and is not necessarily prior art.

In order to meet the emission requirement of a gas engine and reduce emission, a piston with a special-shaped combustion chamber structure with a high in-cylinder vortex ratio for accelerating combustion is adopted, the special-shaped combustion chamber is a combustion space with an unconventional shape and can improve the in-cylinder combustion performance of an engine, but the existing inner cooling oil channel structure is far away from the top surface of the combustion chamber and a throat of the piston, the cooling effect is poor, the local temperature of the piston is overhigh, and the service life of the piston is influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims to at least solve the problem of poor cooling effect of an inner cooling oil channel of a piston provided with a special-shaped combustion chamber in the prior art, and the purpose is realized by the following technical scheme:

the utility model provides a piston, which comprises a piston body and a combustion chamber arranged at the head of the piston body, wherein the radial cross section of the combustion chamber is special-shaped, an inner cooling oil duct is arranged inside the piston body and is annularly arranged between the outer wall of the piston body and the combustion chamber, the radial cross section of the inner cooling oil duct is special-shaped, and the circumferential inner contour of the inner cooling oil duct corresponds to the circumferential contour of the combustion chamber.

The piston provided by the utility model is provided with the inner cooling oil channel matched with the circumferential profile of the special-shaped combustion chamber, so that the cooling distances between the top surface of the piston at the asymmetric part of the special-shaped combustion chamber, the throat of the piston and the inner cooling oil channel are reduced, the cooling effect of the top surface of the piston at the asymmetric part of the special-shaped combustion chamber and the throat of the piston is improved, and the service life of the piston is further prolonged.

In addition, the piston according to the utility model can also have the following additional technical features:

in some embodiments of the present invention, a sectional area of the inner cooling gallery in an axial direction of the piston body is in positive correlation with a wall thickness of the piston, the wall thickness being a thickness between an outer wall of the piston body and the combustion chamber.

In some embodiments of the present invention, a cross section of the inner cooling oil passage in the axial direction of the piston body has a shape of a special-shaped ellipse including an upper circular arc, a lower circular arc, and a straight line segment transitionally connecting the upper circular arc and the lower circular arc.

In some embodiments of the utility model, the radius of the upper arc is not equal to the radius of the lower arc.

In some embodiments of the present invention, a position of the inner cooling gallery in an axial direction of the piston body is close to a bottom of the combustion chamber.

In some embodiments of the utility model, the radial cross-section of the combustion chamber is heart-shaped.

In some embodiments of the present invention, a circumferential inner contour of the inner cooling gallery is heart-shaped, and a circumferential outer contour of the inner cooling gallery is circular.

In some embodiments of the present invention, the combustion chamber, the inner cooling gallery and the piston body are coaxially disposed.

In some embodiments of the utility model, a portion of the piston body between the inner wall of the inner cooling oil passage and the combustion chamber is provided with the same wall thickness.

A second aspect of the utility model provides an engine having a piston as set forth in the first aspect of the utility model.

The engine according to the second aspect of the present invention has the same advantages as the piston according to the first aspect of the present invention, and thus, the description thereof is omitted.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the utility model. Also, like parts are designated by like reference numerals throughout the drawings. In the drawings:

fig. 1 schematically shows a cross-sectional structural view of a piston according to an embodiment of the present invention.

Fig. 2 schematically shows a cross-sectional structure view along a-a in fig. 1.

The reference symbols in the drawings denote the following:

10: piston body, 11: combustion chamber, 12: inner cooling oil passage, 121: upper arc, 122: a lower arc; 123: a straight line segment.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only, and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order described or illustrated, unless specifically identified as an order of performance. It should also be understood that additional or alternative steps may be used.

Although the terms, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, an element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

For convenience of description, spatially relative terms, such as "inner", "outer", "inner", "side", "lower", "below", "upper", "above", and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Thus, the example term "below … …" can include both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

As shown in fig. 1 and 2, a first aspect of the present invention provides a piston, including a piston body 10 and a combustion chamber 11 disposed at a head portion of the piston body 10, a radial cross section of the combustion chamber 11 is in a special-shaped structure, an internal cooling oil gallery 12 is disposed inside the piston body 10, the internal cooling oil gallery 12 is annularly disposed between an outer wall of the piston body 10 and the combustion chamber 11, the radial cross section of the internal cooling oil gallery 12 is in a special shape, and a circumferential inner contour of the internal cooling oil gallery 12 corresponds to a circumferential contour of the combustion chamber 11.

The radial section of the special-shaped combustion chamber 11 is in an unconventional shape and can be in various shapes such as a petal shape, a heart shape, a fan shape and the like. The shape of the inner cooling oil duct 12 and the shape of the special-shaped combustion chamber 11 are designed in a matching mode, namely if the shape of the special-shaped combustion chamber 11 is heart-shaped, the outer contour of the inner cooling oil duct 12 is also heart-shaped, so that the distance between the inner cooling oil duct 12 and the combustion chamber 11 is shortened, when the piston runs, engine oil flows through the inner cooling oil duct 12 to take away heat on the piston, the piston is cooled, and the cooling effect of each position of the head of the piston is improved.

The piston provided by the utility model is provided with the inner cooling oil channel 12 matched with the circumferential profile of the special-shaped combustion chamber 11, the cooling distance between the top surface of the piston at the asymmetric part of the special-shaped combustion chamber 11, the throat of the piston and the inner cooling oil channel 12 is reduced, the cooling effect of the top surface of the piston at the asymmetric part of the special-shaped combustion chamber 11 and the throat of the piston is improved, and the service life of the piston is further prolonged.

In some embodiments of the present invention, the sectional area of the inner cooling gallery 12 in the axial direction of the piston body 10 is in positive correlation with the wall thickness of the piston body 10, which is the thickness between the outer wall of the piston body 10 and the combustion chamber 11.

In some embodiments of the present invention, the shape of the cross section of the inner cooling gallery 12 in the axial direction of the piston body 10 is a shaped ellipse including an upper arc 121, a lower arc 122, and a straight line segment 123 that connects the upper arc 121 and the lower arc 122 in a transition. The upper part and the lower part of the inner cooling oil duct 12 are asymmetric due to the special-shaped oval structure, the upper part is wider and the lower part is narrower or the lower part is wider and the upper part is narrower, the upper arc 121 and the lower arc 122 can also be provided with arcs to incline towards the combustion chamber 11 according to actual needs, and the structure enables engine oil to oscillate along with the up-and-down movement of the piston after entering the inner cooling oil duct 12, so that the cooling effect of the piston is enhanced.

Specifically, the radius of the upper arc 121 is not equal to the radius of the lower arc 122, so that the engine oil oscillates in the inner cooling oil passage 12 along with the reciprocating motion of the piston, the flow speed and the flow area of the engine oil are increased, and the cooling effect is further improved

In some embodiments of the present invention, the position of the inner cooling gallery 12 in the axial direction of the piston body 10 is near the bottom of the combustion chamber 11. The bottom of the combustion chamber 11 is high in temperature and easy to generate carbon deposition, and the central line of the inner cooling oil duct 12 can be parallel to the bottom surface of the combustion chamber 11, so that the cooling effect of the bottom of the combustion chamber 11 is enhanced.

In some embodiments of the utility model, the radial cross-section of the combustion chamber 11 is heart-shaped. The heart-shaped combustion chamber 11 can guide the airflow in the cylinder by utilizing the side wall thereof, guide the mixed gas to generate tumble or turbulent flow, strengthen the flow in the cylinder and further improve the combustion effect.

Further, the inner wall of the inner cooling oil passage 12 is heart-shaped, and the outer wall of the inner cooling oil passage 12 is circular. The inner cooling oil duct 12 is matched with the heart-shaped combustion chamber 11, the distance between the inner cooling oil duct 12 and the combustion chamber 11 is reduced, the cooling effect of the inner cooling oil duct 12 is improved, and the purpose of enlarging the cooling area of the inner cooling oil duct 12 and improving the cooling effect of the inner cooling oil duct on the piston is to make the outer wall contour of the inner cooling oil duct 12 circular.

In some embodiments of the present invention, the combustion chamber 11, the internal cooling oil passage 12 and the piston body 10 are coaxially disposed, so as to facilitate processing.

In some embodiments of the present invention, the portion of the piston body 10 between the inner wall of the internal cooling oil gallery 12 and the combustion chamber 11 is provided with the same wall thickness, so that the internal cooling oil gallery 12 can uniformly cool the combustion chamber 11 in the circumferential direction of the combustion chamber 11, and the influence on the service life of the piston due to the overhigh local temperature is avoided.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are also included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The piston is characterized by comprising a piston body and a combustion chamber arranged at the head of the piston body, wherein the radial section of the combustion chamber is special-shaped, an inner cooling oil duct is arranged inside the piston body and annularly arranged between the outer wall of the piston body and the combustion chamber, the radial section of the inner cooling oil duct is special-shaped, and the circumferential inner contour of the inner cooling oil duct corresponds to the circumferential contour of the combustion chamber.

2. The piston according to claim 1, wherein a sectional area of the inner cooling gallery in an axial direction of the piston body is positively correlated with a wall thickness of the piston, the wall thickness being a thickness between an outer wall of the piston body and the combustion chamber.

3. The piston according to claim 1, wherein a cross section of the inner cooling gallery in the axial direction of the piston body has a shape of a special-shaped ellipse including an upper circular arc, a lower circular arc, and a straight line segment transitionally connecting the upper circular arc and the lower circular arc.

4. The piston of claim 3 wherein the radius of said upper arc is not equal to the radius of said lower arc.

5. The piston according to claim 1, wherein a position of the inner cooling oil passage in an axial direction of the piston body is close to a bottom of the combustion chamber.

6. The piston of claim 1 wherein said combustion chamber is cardioid in radial cross-section.

7. The piston of claim 6 wherein said inner gallery has a generally heart-shaped circumferential inner contour and said inner gallery has a generally circular circumferential outer contour.

8. The piston of claim 7 wherein said combustion chamber, said inner cooling gallery and said piston body are all disposed coaxially.

9. The piston according to any one of claims 1 to 8, wherein a portion of the piston body between the inner wall of the inner cooling gallery and the combustion chamber is provided at an equal wall thickness.

10. An engine, characterized by a piston according to any one of claims 1 to 9.