A new type of spheroidal cast iron piston

Abstract

The utility model relates to the technical field of pistons, and in particular to a novel ductile iron piston, comprising a piston wall, wherein the piston wall is composed of a piston top, a piston head, and a piston skirt, wherein a valve avoidance pit is provided on the top of the piston top, an annular groove is provided around the outer periphery of the piston head, and a face window and two piston pin holes arranged oppositely are provided on the skirt wall of the piston skirt; a piston made of ductile iron is provided with a cooling cavity, an inner cold chamber, an oil discharge hole, and a face window in the ductile iron piston, thereby enhancing the lubrication effect, prolonging the service life of the piston, reducing the wear and friction noise during low-temperature starting of the engine, and improving the performance and reliability of the engine; the ductile iron piston is stronger than a traditional cast aluminum piston, has a smaller expansion coefficient, and has better lubrication and cooling effects; therefore, under the condition that the piston length remains unchanged, the expansion of the piston is lower, so that when the diesel engine is working, the piston stroke is lengthened, the combustion gas expands more fully, the output power is increased, the economy is better, and the probability of cylinder pulling is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of pistons, in particular to a novel spheroidal milled cast iron piston. Background Art

[0002] The piston is a vital component in the car engine, and it plays a key role in the movement of the model. The piston is mainly used to withstand gas pressure: the piston withstands the combustion pressure in the cylinder and transmits this force to the crankshaft through the piston pin and connecting rod, thereby driving the engine to operate.

[0003] A sealed space is formed between the piston and the cylinder wall to ensure that the combustion process takes place in a controlled environment. During combustion, the piston is in direct contact with high-temperature gas, the instantaneous temperature can reach over 2500K, and it withstands a gas pressure of up to 3 to 9 MPa. Therefore, the lubrication conditions between the piston and the cylinder wall have an important influence on engine performance.

[0004] In short, the piston plays a vital role in the car engine. It ensures the normal operation and high efficiency of the engine by bearing high pressure and high temperature, sealing and lubricating, and converting pressure into mechanical power.

[0005] The existing pistons have relatively general lubrication and cooling effects, which to a certain extent limits the service life of the pistons. Moreover, most of them are made of aluminum alloy, which has low wear resistance and heat resistance and a large expansion coefficient. Especially when used in natural gas diesel engines, they are prone to large deformation at high temperatures and piston ablation, resulting in a high probability of cylinder scuffing, causing great damage to the diesel engine.

[0006] Therefore, the present application provides a novel spheroidal milled cast iron piston to overcome the defects of the prior art. Utility Model Content

[0007] The utility model aims to solve the problems that the existing piston lubrication and cooling effects are mediocre, which affects the service life of the piston, and the original aluminum alloy piston is prone to piston ablation, resulting in a high probability of cylinder pulling.

[0008] The technical solution of the utility model provides a new type of spheroidal cast iron piston, the structure of which mainly includes a piston wall, which is composed of three parts: a piston top, a piston head and a piston skirt. A valve avoidance pit is specially designed on the top of the piston top, which can form a combustion chamber with the cylinder wall. Ring grooves are cleverly opened around the outside of the piston head, and the ring grooves include three gas ring grooves and an oil ring groove located below it, to ensure the lubrication and sealing effect of the piston during operation.

[0009] The skirt wall of the piston skirt is designed with two horizontally penetrating face windows and two piston pin holes that are also horizontally penetrating. The two face windows and the two piston pin holes are arranged opposite to each other, and the piston pin holes and the face windows are arranged at intervals to maintain the structural stability and functionality of the piston skirt. In particular, a vertically arranged connection hole is also opened in the piston pin hole to facilitate connection with other components.

[0010] In order to enhance the heat dissipation performance of the piston, a cooling cavity is specially set inside the piston wall. In addition, an inner cooling chamber is also opened on the inner top wall of the piston wall, which is connected to the cooling cavity to form an efficient cooling system, effectively reducing the temperature of the piston during operation and improving its service life and performance stability.

[0011] The beneficial effects of a novel spheroidal cast iron piston provided by the utility model are:

[0012] The utility model increases the contact area between the engine oil and the piston and improves the cooling effect by providing a cooling cavity and an inner cooling chamber; by providing a surface window, the engine oil can flow out faster after absorbing heat, increasing the engine oil between the piston wall and the cylinder wall, enhancing the lubrication and cooling effects, and extending the service life of the piston;

[0013] The piston is made of ductile iron, which has a small expansion coefficient, high wear resistance and heat resistance, which reduces piston ablation, reduces the probability of cylinder scuffing, avoids damage to the diesel engine, and extends the service life of the engine. Ductile iron has better low-temperature stability, reduces wear and friction noise when the engine is started at low temperature, and improves the performance and reliability of the engine;

[0014] The piston made of ductile iron has a cooling cavity, an inner cooling chamber, an oil discharge hole and a face window provided inside the ductile iron piston, thereby enhancing the lubrication effect, prolonging the service life of the piston, reducing the wear and friction noise during low-temperature starting of the engine, and improving the performance and reliability of the engine. Compared with a traditional cast aluminum piston, the ductile iron piston has a greater strength, a smaller expansion coefficient, and better lubrication and cooling effects. Therefore, when the piston length remains unchanged, the expansion of the piston is lower, so that when the diesel engine is working, the piston stroke is lengthened, the combustion gas expands more fully, the output power is increased, the economy is better, and the probability of cylinder scuffing is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A three-dimensional diagram of an embodiment of the utility model;

[0016] Figure 2 It is a front view of an embodiment of the utility model;

[0017] Figure 3 It is a front view of another perspective of the embodiment of the utility model;

[0018] Figure 4 It is a partial cutaway view of an embodiment of the utility model;

[0019] Figure 5 A partial cutaway view from another perspective of an embodiment of the utility model;

[0020] Figure 6 A three-dimensional cutaway diagram of an embodiment of the utility model;

[0021] Figure 7 It is a front cross-sectional view of an embodiment of the utility model.

[0022] Among them, 1. Piston wall; 11. Piston top; 12. Piston head; 13. Piston skirt; 2. Valve avoidance pit; 3. Ring groove; 31. Gas ring groove; 32. Oil ring groove; 4. Face window; 5. Piston pin hole; 6. Connecting hole; 7. Cooling chamber; 8. Internal cooling chamber. DETAILED DESCRIPTION

[0023] In order to make the technical means, technical features, utility model objectives and technical effects achieved by the utility model easy to understand, the utility model is further explained below in conjunction with specific diagrams; it is obvious that the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments; based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the utility model.

[0024] Embodiment 1

[0025] As attached Figure 1 To Attachment Figure 7 As shown: a new type of ductile cast iron piston, including a piston wall 1, the piston wall 1 is composed of a piston top 11, a piston head 12, and a piston skirt 13 arranged in sequence from top to bottom, the top of the piston head 12 is fixedly connected to the piston top 11, and the bottom is fixedly connected to the piston skirt 13, the top of the piston top 11 is provided with a valve avoidance pit 2, the valve avoidance pit 2 and the cylinder wall form a combustion chamber for the combustion of combustible mixture, and the piston is made of ductile cast iron as a whole.

[0026] Four ring grooves 3 are sequentially provided on the outer side wall of the piston head 12 from top to bottom, the top three of the four ring grooves 3 are gas ring grooves 31, and the bottom one is an oil ring groove 32. The oil ring groove 32 is provided with a plurality of oil leakage holes connected with the cooling chamber. The function of the gas ring groove 31 is to ensure the sealing between the piston and the cylinder to prevent the high-temperature and high-pressure combustion gas in the cylinder from leaking into the crankcase in large quantities, and at the same time, most of the heat from the top of the piston is transferred to the cylinder wall, which is then taken away by cooling water or air. The oil ring groove 32 is used to scrape off excess engine oil on the cylinder wall and apply a uniform engine oil film on the cylinder wall, which can prevent the engine oil from entering the cylinder and burning, and can also reduce the wear of the piston, piston ring and cylinder and reduce the friction resistance.

[0027] Two oppositely arranged surface windows 4 are provided on the side wall of the piston skirt 13, and both surface windows 4 penetrate the piston skirt 13, thereby improving the lubrication effect and more than doubling the service life. The opening size and number of the surface windows 4 in the device can be adjusted according to customer needs, and at least only one surface window 4 can be provided.

[0028] The piston skirt 13 is also provided with two piston pin holes 5 which are arranged opposite to each other. The piston pin holes 5 penetrate the piston skirt 13 and are used for installing the piston pin. The two face windows 4 and the two piston skirts 13 are arranged at intervals, and the heights of the two piston skirts 13 are lower than the heights of the two face windows 4. The inner wall of the piston skirt 13 is provided with four vertically arranged connecting holes 6, and each two connecting holes 6 form a group, which are arranged at the lower side of the piston pin hole 5 and are connected to the piston pin hole 5. The connecting hole 6 can be a pin hole or a bolt hole. The piston pin hole 5 and the connecting hole 6 work together to install the piston pin in the piston pin hole 5 to prevent the piston pin from falling off.

[0029] A cooling cavity 7 is provided in the piston wall 1, and an inner cooling chamber 8 is provided at the inner top of the piston wall 1. The top of the cooling cavity 7 is communicated with the inner cooling chamber 8. The oil pump transports the oil in the oil pan to the cooling cavity 7 and the inner cooling chamber 8 to cool the piston. At the same time, part of the oil is discharged from the oil discharge hole in the oil ring groove 32, and the other part flows out from the two surface windows 4 to lubricate the cylinder wall, thereby improving the lubrication effect and increasing the service life of the piston by more than double.

[0030] Working method: Install the piston pin in the two piston pin holes 5, and install bolts or pins in the connecting hole 6 to fix the piston pin. During lubrication, the oil pump transports the oil in the oil pan to the cooling chamber 7 and the inner cooling chamber 8 to cool the piston. At the same time, part of the oil is discharged from the oil discharge hole in the oil ring groove 32, and the other part flows out from the two surface windows 4 to lubricate the cylinder wall.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. That is, all equivalent changes and modifications made according to the content of the patent application scope of the present invention should fall within the technical scope of the present invention.

Claims

1. A new type of spheroidal cast iron piston, characterized by: The invention comprises a piston wall (1), wherein the piston wall is composed of a piston top (11), a piston head (12), and a piston skirt (13); a valve avoidance pit (2) is provided on the top of the piston top (11); an annular groove (3) is provided around the outside of the piston head (12); and a surface window (4) and two piston pin holes (5) arranged opposite to each other are provided on the skirt wall of the piston skirt (13).

2. A novel spheroidal cast iron piston according to claim 1, characterized in that: There are two face windows (4) in total. The two face windows (4) and the two piston pin holes (5) all penetrate the piston skirt (13) horizontally. The piston pin holes (5) and the face windows (4) are arranged at intervals. A vertically arranged connecting hole (6) is provided in the piston pin hole (5).

3. A novel spheroidal cast iron piston according to claim 1, characterized in that: A cooling chamber (7) is provided in the piston wall (1).

4. A novel spheroidal cast iron piston according to claim 3, characterized in that: An inner cooling chamber (8) is provided on the inner top wall of the piston wall (1), and the inner cooling chamber (8) is communicated with the cooling cavity (7).

5. A novel spheroidal cast iron piston according to claim 1, characterized in that: The ring groove (3) comprises three air ring grooves (31) and one oil ring groove (32), and the air ring groove (31) is arranged above the oil ring groove (32).

6. A novel spheroidal cast iron piston according to claim 1, characterized in that: The piston wall (1) is made of ductile iron.

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