Ceramic top combined piston

Abstract

The invention provides a ceramic top combined piston which comprises a ceramic piston top, a metal connector, an auxiliary locking body and a buffer material, the section of the ceramic piston top is in an inverted I shape with the large outside and the small inside, the ceramic piston top is sleeved with the metal connector, and the portion between the metal connector and the ceramic piston top is filled with the buffer material. An auxiliary locking body used for achieving fixed connection between the ceramic piston top and the metal connecting body is connected outside the metal connecting body in a sleeved mode. According to the ceramic top combined piston, in the working process, high-temperature fuel gas is prevented from making direct contact with a metal part, effective protection of the ceramic piston top on the metal part is achieved, friction and impact between the ceramic piston top and the metal part are relieved through auxiliary filling buffer materials, and the ceramic piston top is protected against damage.

Description

Technical Field

[0001] The present invention belongs to the technical field of equipment manufacturing, and particularly relates to a ceramic top combined piston. Background Art

[0002] In the field of diesel engine design and R & D, the use of heat insulation technology for heat-receiving components to reduce the heat transferred from in-cylinder gas to the cooling medium has always been an effective technical approach to reduce the volume of auxiliary systems and improve the power density of power plants. Generally speaking, diesel engine pistons are made of aluminum alloy or steel materials, with relatively high thermal conductivity, resulting in a relatively large amount of heat transferred from in-cylinder gas. Preparing the piston top with low-thermal-conductivity and high-temperature-resistant ceramic materials and using the high thermal resistance characteristics of ceramics to hinder the heat transferred from in-cylinder gas to the piston is an effective method to reduce the heat transfer amount. There are huge differences in hardness, impact resistance, and plastic deformation ability between ceramic materials and metal materials. Directly preparing ceramic pistons cannot meet the high-frequency impact use in the high-temperature and high-pressure alternating environment of diesel engines. Using a combined component of a ceramic top and a metal matrix is a feasible technical solution, and the reliable connection design between ceramic materials and metal materials is the key issue for the usability of the component. On the one hand, the thermal deformation of ceramic materials is one-fourth of that of metals, and it is difficult to ensure the working life of the piston by relying on welding methods; on the other hand, most of the existing ceramic top combined schemes adopt a connection method of directly pressing the piston top on the piston body, and its metal pressing structure is directly exposed to the high-temperature gas environment, and there is still a high amount of heat transfer between the metal pressing structure and the piston body. Summary of the Invention

[0003] In view of this, the present invention aims to propose a ceramic top combined piston to solve the problem of direct exposure of metal materials in a high-temperature gas environment.

[0004] To achieve the above object, the technical solution of the present invention is realized as follows: A ceramic top combined piston includes a ceramic piston top, a metal connecting body, an auxiliary locking body, and a buffer material. The cross-section of the ceramic piston top is in an inverted "I" shape with the outside larger and the inside smaller. The ceramic piston top is sleeved with the metal connecting body on the outside, and a buffer material is filled between the metal connecting body and the ceramic piston top. The metal connecting body is sleeved with an auxiliary locking body on the outside for realizing the fixed connection between the ceramic piston top and the metal connecting body.

[0005] Further, the ceramic piston top includes a working part and a connecting part. The working part needs to be processed into the shape of the piston top combustion chamber according to the working requirements of the engine, and the connecting part is used for fixedly connecting with metal components such as the metal connecting body.

[0006] Further, the auxiliary locking body is threadedly connected or welded to the metal connecting body, and after being fixedly connected, it can restrain the splitting or deformation process of the metal connecting body and prevent the metal connecting body from loosening from the ceramic piston top.

[0007] Further, the buffer material is a low-modulus, low-strength, high-temperature-resistant metal material.

[0008] Further, the buffer material is copper or nickel.

[0009] Further, the metal connector includes two or more separate parts, which are assembled with the connecting part of the ceramic piston crown in the separated state, and after forming the combined state, the metal connector is restricted from separating by the auxiliary locking body.

[0010] Further, the metal connector includes a plurality of deformable hook claws, which are assembled with the connecting part of the ceramic piston crown in the deformed state and cannot be disassembled in the non-deformed state, and then the metal connector is restricted from deforming by the auxiliary locking body.

[0011] Compared with the prior art, the ceramic crown combined piston of the present invention has the following advantages: (1) For the ceramic crown combined piston of the present invention, by adopting the inverted "I" shape with a large outer part and a small inner part for the ceramic piston crown, and machining the piston crown shape with the large outer circle as the working part, the areas where the piston crown is in direct contact with the high-temperature gas are all made of ceramic material, avoiding the direct exposure of the metal material in the high-temperature gas environment, and effectively protecting the metal components by the ceramic piston crown during the working process.

[0012] (2) For the ceramic crown combined piston of the present invention, by adopting the inverted "I" shape with a large outer part and a small inner part for the ceramic piston crown, the connection between the piston crown and the piston body is realized by pressing the small inner circular connecting part, and the friction and impact between the ceramic piston crown and the metal components are relieved by the auxiliary filling buffer material, protecting the ceramic piston crown from being damaged. Description of the Drawings

[0013] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 is a schematic diagram of the first embodiment of the ceramic crown combined piston according to the embodiment of the present invention; Figure 2 is a schematic diagram of the second embodiment of the ceramic crown combined piston according to the embodiment of the present invention.

[0014] Description of the Reference Numerals: 1 - Ceramic piston crown; 11 - Working part; 12 - Connecting part; 2 - Metal connector; 3 - Auxiliary locking body; 4 - Buffer material. Detailed Embodiments

[0015] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0016] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0017] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific circumstances.

[0018] The present invention will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0019] A ceramic top combined piston, as Figure 1 and Figure 2 shown, includes a ceramic piston top 1, a metal connecting body 2, an auxiliary locking body 3 and a buffer material 4. The cross-section of the ceramic piston top 1 is in an inverted "I" shape with a larger outer and a smaller inner. The outer part of the groove in the middle of the ceramic piston top 1 is sleeved with the metal connecting body 2, and the buffer material 4 is filled between the metal connecting body 2 and the ceramic piston top 1. The auxiliary locking body 3 is sleeved outside the metal connecting body 2, and the auxiliary locking body 3 is used to realize the fixed connection between the ceramic piston top 1 and the metal connecting body 2.

[0020] In the ceramic top combined piston of this solution, during the working process, it hinders the high-temperature gas from directly contacting the metal connecting body, realizes the effective protection of the metal connecting body by the ceramic piston top, and relieves the friction and impact between the ceramic piston top and the metal connecting body through the attached buffer material, protecting the ceramic piston top 1 from being damaged.

[0021] The ceramic piston top 1 includes a working part 11 and a connecting part 12. The working part 11 needs to be processed into the shape of the piston top combustion chamber according to the working requirements of the engine, and the connecting part 12 is used to be fixedly connected with metal components such as the metal connecting body.

[0022] The auxiliary locking body 3 is tightly and fixedly connected to the metal connecting body 2 by means including but not limited to threaded welding, etc., and after being fixedly connected, it can restrict the separation or deformation process of the metal connecting body 2 and prevent the metal connecting body 2 from loosening from the ceramic piston top 1; The buffer material is a low-modulus, low-strength, high-temperature-resistant metal material, and the specific optional range includes but is not limited to copper, nickel, etc.

[0023] In one embodiment, the metal connecting body 2 includes two or more separated parts, which are assembled with the connecting part 11 of the ceramic piston top 1 in the separated state to form a combined state to ensure no loosening. After assembly, the auxiliary locking body 3 restricts the metal connecting body 2 from being separated, ensuring a stable connection.

[0024] In another embodiment, the metal connecting body 2 includes a plurality of deformable hook claws, which are assembled with the connecting part 11 of the ceramic piston top 1 in the deformed state and cannot be disassembled in the non-deformed state. After assembly, the auxiliary locking body 3 restricts the metal connecting body 2 from deforming, ensuring a stable connection.

[0025] An assembly process of a ceramic top combined piston is as follows: Embodiment 1: As Figure 1 shown, the metal connecting body 2 is evenly divided into two parts; during use, on the premise of filling the buffer material 4, the two parts of the metal connecting body 2 are assembled on the ceramic piston top 1, and then the metal connecting body 2 and the auxiliary locking body 3 are assembled by means including but not limited to threaded welding, etc., and the auxiliary locking body 3 restricts the two parts of the metal connecting body 2 from separating, ensuring a stable fixed connection between the ceramic piston top 1 and the metal connecting body 2; Embodiment 2: As Figure 2 shown, the connecting part of the metal connecting body 2 is a multi-branch structure and uses a high-toughness deformable material; during use, on the premise of making each branch of the connecting part elastically deform, the assembly of the metal connecting body 2 and the ceramic piston top 1 is realized on the basis of filling the buffer material 4, and then the metal connecting body 2 and the auxiliary locking body 3 are assembled by means including but not limited to threaded welding, etc., and the auxiliary locking body 3 can prevent each branch of the metal connecting body 2 from deforming, ensuring a stable fixed connection between the ceramic piston top 1 and the metal connecting body 2.

[0026] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A ceramic top combined piston, characterized in that: It includes a ceramic piston top, a metal connector, an auxiliary locking body and a buffer material. The cross-section of the ceramic piston top is an inverted "I" shape with a large outside and a small inside. The outside of the ceramic piston top is sleeved with a metal connector, and a buffer material is filled between the metal connector and the ceramic piston top. The outside of the metal connector is sleeved with an auxiliary locking body for achieving a fixed connection between the ceramic piston top and the metal connector.

2. A ceramic top combined piston according to claim 1, characterized in that: The ceramic piston top includes a working part and a connecting part. The working part needs to be processed into a piston top combustion chamber according to the working requirements of the engine, and the connecting part is used to be fixedly connected to metal parts such as metal connectors.

3. A ceramic top combined piston according to claim 1, characterized in that: The auxiliary locking body is threadedly connected or welded to the metal connecting body, and after being fixedly connected, it can restrict the separation or deformation process of the metal connecting body, thereby preventing the metal connecting body and the ceramic piston top from loosening.

4. A ceramic top combined piston according to claim 1, characterized in that: The buffer material is a low modulus, low strength, high temperature resistant metal material.

5. A ceramic top combined piston according to claim 4, characterized in that: The buffer material is copper or nickel.

6. A ceramic top combined piston according to claim 1, characterized in that: The metal connector includes two or more separate parts, which are assembled with the connecting part of the ceramic piston top in a separated state. After forming a combined state, the auxiliary locking body constrains the metal connector to be unable to be separated.

7. The ceramic top combined piston according to claim 1, characterized in that: The metal connector includes a plurality of deformable hook claws, which are assembled with the connecting part of the ceramic piston top in a deformed state and cannot be disassembled in a non-deformed state. Then, the auxiliary locking body constrains the metal connector to prevent deformation.

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