A pressure stabilizing piston and engine

Abstract

The application discloses a pressure stabilizing piston and relates to the technical field of engines. A two-way adjusting valve is arranged in a channel hole. The two-way adjusting valve can be bidirectionally conducted. When external air pressure exceeds initial air inlet pressure P0, the two-way adjusting valve is opened to allow air flow to enter a pressure stabilizing cavity. When internal air pressure of the pressure stabilizing cavity exceeds initial air outlet pressure P0', the two-way adjusting valve is opened to allow air flow to be discharged from the pressure stabilizing cavity. The pressure stabilizing cavity can accommodate air. During a working stroke of the engine, the air is allowed to enter the pressure stabilizing cavity through the two-way adjusting valve, the increasing speed of second ring bank pressure P2 formed by two piston rings and a piston body is reduced, the first piston ring can be tightly attached to the lower side of a first ring groove under the action of P1, an air leakage channel is not easily formed, and air leakage is reduced. At the end of combustion and work or during other strokes, the air stored in the pressure stabilizing cavity is released, the second ring bank pressure P2 is increased, the running posture of the second piston ring is adjusted, the second piston ring is tightly attached to the lower side of a second ring groove, and good sealing is formed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engines, and more particularly to a pressure stabilizing piston. BACKGROUND

[0002] With the continuous iterative development of the engine industry, the control of the blow-by gas amount of the engine is increasingly valued by engine manufacturers. As an important indicator of the overall performance of the engine, the blow-by gas amount is related to the power conversion efficiency of the engine, the service life of the oil and gas seal rings, the oil change cycle and other important performance that customers care about.

[0003] The prior art is to mechanically process a special-shaped groove between the first and second ring grooves of the piston head, to achieve the effect of reducing the gas pressure by increasing the volume. The existing piston pressure reduction scheme adopts structures such as a large shallow groove 01, a hawk beak groove 02, and a trapezoidal groove 03 on the second ring bank, in combination with Figures 1 to 3 As shown in the figures, the structures of the second ring bank provided with a large shallow groove, a hawk beak groove, and a trapezoidal groove in the prior art are respectively shown.

[0004] The main disadvantages of the prior art using a special-shaped groove are: 1. It can only passively increase the volume and cannot actively adjust the gas pressure. The first ring is in a critical state of floating and not floating before the upper and lower sides of the first ring reach pressure balance, and the piston ring vibrates in this critical state, resulting in poor gas sealing effect. 2. It can only increase the volume on one side, and cannot automatically release gas to supplement the gas pressure in the second ring groove in the case of insufficient gas pressure in the second ring bank, so that the second ring cannot be tightly attached to the second ring groove to form an effective seal, ultimately causing the excess gas to leak through the second ring into the crankcase, resulting in power loss and increased blow-by gas of the engine.

[0005] Therefore, how to design and optimize the sealing performance of the piston ring groove and the piston ring, improve the fit effect of the piston ring groove and the piston ring, reduce the blow-by gas amount and oil consumption, reduce the power loss of the engine, and improve the overall performance of the engine is the most pressing problem to be solved at present. SUMMARY

[0006] The present application provides a pressure stabilizing piston, which is provided with a pressure stabilizing cavity on the piston body, and cooperates with a bidirectional regulating valve to shorten the duration of pressure balance on both sides of the two piston rings, reduce the blow-by gas amount, thereby reducing the power loss, and reducing the vibration of the piston ring. The specific scheme is as follows:

[0007] A pressure stabilizing piston, comprising a piston body, wherein the piston body is provided with two piston rings, including a first piston ring installed in a first ring groove and a second piston ring installed in a second ring groove;

[0008] At least one pressure-stabilizing chamber is provided inside the piston body, and at least one channel hole is provided on the side wall of the piston body, the channel hole communicating with the pressure-stabilizing chamber and the outside; the channel hole is located between the two piston rings;

[0009] A bidirectional regulating valve is provided in the channel hole. The bidirectional regulating valve is used to open when the external air pressure exceeds the initial inlet pressure P0 to allow airflow to enter the pressure stabilizing chamber. The bidirectional regulating valve is also used to open when the internal air pressure exceeds the initial outlet pressure P0' to allow airflow to exit the pressure stabilizing chamber.

[0010] Optionally, the voltage-stabilizing cavity is an annular channel.

[0011] Optionally, the annular housing constituting the pressure stabilizing chamber is fixed to a ring provided on the piston body.

[0012] Optionally, the cross-section of the annular shell is U-shaped, and its open end is welded to the insert ring to form the pressure stabilizing cavity. The pressure stabilizing cavity structure is embedded into the piston body by casting.

[0013] Optionally, the initial intake pressure P0 is:

[0014] P0 = 0.2 * P, where P is the engine's maximum burst pressure.

[0015] Optionally, the initial outlet pressure P0' is:

[0016] P0'=0.2*P3, where: P3 is the pressure of the third ring shore.

[0017] Optionally, the two piston rings and the piston body form a second ring land, and the second ring land and the cylinder liner form a clearance volume V2. The volume V1 of the pressure stabilizing chamber satisfies:

[0018] V1 is 2 to 4 times that of V2.

[0019] Optionally, the channel holes are evenly arranged in a circumferential direction, and the number of channel holes is 4 to 8.

[0020] The present invention also provides an engine comprising the pressure-stabilizing piston described in any of the preceding claims.

[0021] Compared to existing technologies, this invention provides a pressure-stabilizing piston. The piston body has at least one pressure-stabilizing chamber inside, which has a space to accommodate gas. A channel hole connects the pressure-stabilizing chamber to the outside environment and is located between two piston rings. A bidirectional regulating valve is installed inside the channel hole. The bidirectional regulating valve is bidirectionally oriented; it opens when the outside air pressure exceeds the initial intake pressure P0 to allow airflow into the pressure-stabilizing chamber, and opens when the internal air pressure of the pressure-stabilizing chamber exceeds the initial outlet pressure P0' to allow airflow out of the pressure-stabilizing chamber. The pressure-stabilizing chamber can accommodate gas. During the engine's power stroke, the bidirectional regulating valve allows gas to enter the pressure-stabilizing chamber, reducing the rate of increase of the second ring land pressure P2 formed by the two piston rings and the piston body. This ensures that the first piston ring, under the action of P1, can tightly fit against the lower side of the first ring groove throughout the entire process, providing a good seal and preventing the formation of a leakage channel, thus reducing air leakage. It also prevents engine oil from rising and reduces oil consumption. At the end of combustion or during other strokes, the gas stored in the pressure stabilizing chamber is released, increasing the pressure of the second ring land P2, adjusting the running posture of the second piston ring, so that the second piston ring fits tightly against the lower side of the second ring groove, forming a good seal. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 A schematic diagram of a piston with a large shallow groove in existing technology;

[0024] Figure 2 A schematic diagram of a piston with a beak-shaped groove in existing technology;

[0025] Figure 3 A schematic diagram of a piston with a trapezoidal groove in the prior art;

[0026] Figure 4 A schematic diagram of the stabilizing piston and cylinder liner during the power stroke, provided by the present invention.

[0027] Figure 5 A schematic diagram of the structure of the pressure-stabilizing piston provided by the present invention;

[0028] Figure 6 This is a magnified view of a portion of the voltage stabilizing chamber;

[0029] Figure 7 This is a top view of the pressure stabilizing chamber and the channel hole.

[0030] The image includes:

[0031] Piston body 1, pressure stabilizing chamber 2, channel hole 3, bidirectional regulating valve 4, piston ring 5, first piston ring 51, second piston ring 52, insert ring 6, cylinder liner 7, annular housing 8. Detailed Implementation

[0032] The core of this invention is to provide a pressure-stabilizing piston, which has a pressure-stabilizing chamber on the piston body and works with a bidirectional regulating valve to shorten the duration of pressure balance on both sides of the two piston rings, reduce air leakage, thereby reducing power loss and reducing piston ring vibration.

[0033] To enable those skilled in the art to better understand the technical solution of the present invention, the pressure-stabilizing piston of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] Combination Figures 4 to 7 As shown, the present invention provides a pressure-stabilizing piston, including a piston body 1, on which two piston rings 5 ​​are provided. The piston rings 5 ​​include a first piston ring 51 installed in a first ring groove and a second piston ring 52 installed in a second ring groove. Figure 4 , Figure 5 The first annular groove shown is provided on the insert ring 6, and the second annular groove is provided on the piston body 1; the first piston ring 51 and the second piston ring 52 are axially ( Figure 4 There is a certain gap in the vertical direction.

[0035] The piston body 1 has at least one pressure-stabilizing chamber 2 inside. The pressure-stabilizing chamber 2 is a cavity structure inside the piston body 1, and it can hold a certain amount of gas.

[0036] At least one channel hole 3 is provided on the side wall of the piston body 1. The channel hole 3 serves to connect the inside and outside. The channel hole 3 connects the pressure stabilizing chamber 2 and the outside. Gas from the outside can enter the pressure stabilizing chamber 2 through the channel hole 3, and gas in the pressure stabilizing chamber 2 can flow to the outside through the channel hole 3.

[0037] The channel hole 3 is located between the two piston rings 5, and is combined with Figure 4 As shown, the channel hole 3 is located below the first piston ring 51 and above the second piston ring 52.

[0038] A bidirectional regulating valve 4 is installed inside the channel hole 3. The bidirectional regulating valve 4 allows gas to flow in both directions, that is, the airflow can flow from the inside to the outside (from the pressure stabilizing chamber 2 to the outside) or from the outside to the inside (from the outside to the pressure stabilizing chamber 2). The bidirectional regulating valve 4 has a preset opening pressure. The bidirectional regulating valve 4 is used to open when the outside air pressure exceeds the initial inlet pressure P0 to allow the airflow to enter the pressure stabilizing chamber 2. The bidirectional regulating valve 4 is used to open when the internal air pressure exceeds the initial outlet pressure P0' to allow the airflow to exit the pressure stabilizing chamber 2.

[0039] The pressure-stabilizing piston of this invention is applied to an engine. Figure 4 The area above the image shows the region where the mixed gas combustion does work, and the arrows indicate the direction of airflow. Figure 4 In the middle, the space formed by the two piston rings 5 ​​and the piston body 1 is the second ring land II, the area above the first piston ring 51 is the first ring land I, and the area below the second piston ring 52 is the third ring land III. The first ring land I, the second ring land II, and the third ring land III are all annular spaces formed between the piston body 1 and the cylinder liner 7, and are separated by the first piston ring 51 and the second piston ring 52 to form three ring lands.

[0040] Combination Figure 4 During the engine's power stroke, when the air-fuel mixture is burning, the piston's first ring land pressure P1 is much greater than the second ring land pressure P2, pressing the first piston ring 51 against the lower side of the first ring groove. As the power stroke changes, P2 increases rapidly. When P2 approaches P1, the first piston ring 51 is suspended within the piston's first ring groove, easily forming a venting channel and causing a rapid increase in leakage. Therefore, when the pressure of P2 reaches the initial intake pressure P0 of the two-way regulating valve 4, the two-way regulating valve 4 automatically opens, reducing the rate of increase of P2, disrupting the balance between P2 and P1, and maintaining P1 greater than P2. This ensures that the first piston ring 51, under the action of P1, can tightly adhere to the lower side of the first ring groove throughout the entire process, maintaining a good seal, preventing the formation of a venting channel, reducing leakage, and also preventing oil from rising and reducing oil consumption.

[0041] At the end of combustion or in other strokes, before the piston reaches the bottom dead center, most of the chemical energy released by combustion is converted into mechanical energy, and P2 decreases rapidly. When P2 approaches P3, the second piston ring 52 is suspended in the second ring groove, and the sealing effect decreases significantly. At this time, the bidirectional regulating valve 4 opens, releasing the gas stored in the pressure stabilizing chamber 2, increasing the pressure of P2, and adjusting the running posture of the second piston ring 52 so that the second piston ring 52 fits tightly against the lower side of the second ring groove, forming a good seal.

[0042] The pressure-stabilizing piston of this invention, by setting a pressure-stabilizing chamber 2, shortens the time it takes for P2 and P1, and for P2 and P1 to reach a balanced state, and shortens the suspension time of the first piston ring 51 and the second piston ring 52. Therefore, it can reduce air leakage and thus reduce engine power loss. In conventional piston structures, when the pressure of P1 is too high, a large amount of gas will instantaneously enter the second ring land II. The gas entering the second ring land II will impact the first piston ring 51 in the reverse direction, causing the first piston ring 51 to vibrate. The pressure-stabilizing chamber 2 of this invention can accommodate more gas, thus reducing vibration. Similarly, it can also reduce the vibration of the second piston ring 52.

[0043] Based on the above solution, the voltage stabilizing cavity 2 provided by the present invention is a circular channel, combined with... Figure 7 As shown, the entire pressure-stabilizing chamber 2 is a ring structure coaxially arranged with the piston body 1, forming a larger accommodating space and better performing the buffering function. Of course, the present invention does not exclude the use of segmented pressure-stabilizing chambers 2, that is, setting up several independent pressure-stabilizing chambers 2, each pressure-stabilizing chamber 2 being individually connected to a corresponding channel hole 3, which can also play a buffering role. Therefore, these corresponding structures should also be included within the protection scope of the present invention.

[0044] Combination Figure 6 As shown, a portion of the surface of the pressure stabilizing chamber 2 is formed by the inner wall of the annular shell 8. The annular shell 8, which constitutes the pressure stabilizing chamber 2, is fixed to the insert ring 6 provided on the piston body 1. When casting the piston body 1, the annular shell 8 and the insert ring 6 are first connected together by welding to form a whole, and then the piston is formed by casting. The pressure stabilizing chamber structure is embedded in the piston body by casting.

[0045] Combination Figure 6 As shown, the pressure stabilizing cavity 2 is formed by an annular shell 8 and a retaining ring 6. The annular shell 8 has a U-shaped cross-section, and its open end is welded to the retaining ring 6 to form the pressure stabilizing cavity 2. The pressure stabilizing cavity structure is embedded into the piston body 1 by casting. The retaining ring 6 is used to fix and position the annular shell 8. Of course, the present invention does not exclude the possibility of setting the cross-section of the retaining ring 6 to be closed on all four sides. These specific configurations should be included within the protection scope of the present invention.

[0046] Here, the initial intake pressure P0 and the initial exhaust pressure P0' are defined as follows:

[0047] The initial intake pressure P0 is:

[0048] P0 = 0.2 * P, where P is the engine's maximum burst pressure.

[0049] The initial exhaust pressure P0' is:

[0050] P0'=0.2*P3, where: P3 is the pressure of the third ring shore.

[0051] The intake and exhaust processes are two different operating conditions, so the initial intake pressure P0 and the initial exhaust pressure P0' are set to different values. The specific values ​​can be determined based on the piston's operating conditions.

[0052] Based on any of the above technical solutions and their combinations, in this invention, the two piston rings 5 ​​and the piston body 1 form a second ring land, and the second ring land and the cylinder liner 7 form a clearance volume V2. The volume V1 of the pressure stabilizing chamber 2 satisfies: V1 = (2~4) * V2. That is, the size of the space V1 is 2-4 times the size of the space V2. This range is a preferred solution and is not limited to it; it can also be set according to specific working conditions.

[0053] The channel holes 3 are evenly arranged in a circumferential direction, and the number of channel holes 3 is 4 to 8. (Combined) Figure 7 As shown, the structure with four channel holes 3 is illustrated. The channel holes 3 and the annular shell 8 are fixed as one piece, and the whole formed by the two is fixed on the insert ring 6. After casting, the channel holes 3 are surrounded inside the piston body 1.

[0054] The present invention also provides an engine including the aforementioned pressure-stabilizing piston, which can achieve the same technical effect.

[0055] The pressure stabilizing chamber 2 structure can automatically match the pressure difference between the second ring land and its upper and lower first and third ring lands during piston operation, resulting in a better sealing effect. It can adjust the sealing condition of the piston body, piston rings, and cylinder liner almost throughout the entire stroke. The pressure stabilizing chamber 2 structure can realize the functions of pressure reduction and compensation for P2 pressure.

[0056] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A pressure-stabilizing piston, characterized in that, Includes a piston body (1), on which two piston rings (5) are provided, including a first piston ring (51) installed in a first ring groove and a second piston ring (52) installed in a second ring groove. At least one pressure-stabilizing chamber (2) is provided inside the piston body (1), and at least one channel hole (3) is provided on the side wall of the piston body (1). The channel hole (3) is connected to the pressure-stabilizing chamber (2) and the outside. The channel hole (3) is located between the two piston rings (5). A two-way regulating valve (4) is provided in the channel hole (3). The two-way regulating valve (4) is used to open when the external air pressure exceeds the initial inlet pressure P0 to allow airflow to enter the pressure stabilizing chamber (2). The two-way regulating valve (4) is used to open when the internal air pressure exceeds the initial outlet pressure P0' to allow airflow to exit the pressure stabilizing chamber (2). The initial intake pressure P0 is: P0 = 0.2 * P, where P is the engine's maximum burst pressure; The initial outlet pressure P0' is: P0'=0.2*P3, where: P3 is the pressure of the third ring shore.

2. The pressure-stabilizing piston according to claim 1, characterized in that, The pressure stabilizing cavity (2) is a circular channel.

3. The pressure-stabilizing piston according to claim 2, characterized in that, The annular housing (8) constituting the pressure stabilizing chamber (2) is fixed to the insert (6) provided on the piston body (1).

4. The pressure-stabilizing piston according to claim 3, characterized in that, The cross-section of the annular shell (8) is U-shaped, and its open end is welded to the insert ring (6) to form the pressure stabilizing cavity (2). The pressure stabilizing cavity structure is embedded into the piston body (1) by casting.

5. The pressure-stabilizing piston according to any one of claims 1 to 4, characterized in that, Two piston rings (5) and the piston body (1) form a second ring land, and the second ring land and the cylinder liner (7) form a gap volume V2. The volume V1 of the pressure stabilizing chamber (2) satisfies: V1 is 2 to 4 times that of V2.

6. The pressure-stabilizing piston according to claim 5, characterized in that, The channel holes (3) are evenly arranged in the circumferential direction, and the number of channel holes (3) is 4 to 8.

7. An engine, characterized in that, Includes the pressure-stabilizing piston as described in any one of claims 1 to 6.

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