Oil pumping prevention piston ring set structure for urban bus brake air compressor

Abstract

A piston moves in an air cylinder, the bottom of the air cylinder is connected with a crankcase, an annular groove is formed in the outer wall of the piston, a piston ring is arranged in the annular groove, an opening is formed in the circumferential direction of the piston ring, the two ends of the opening are in a step shape, and a lap joint type opening is formed. When the piston ring is arranged in the air cylinder to work, the opening is closed to form bent sealing, and an oil scraping notch groove is formed in the bottom of the periphery of the piston ring. According to the utility model, the pumping efficiency of urban buses can be improved, and downward blow-by can be reduced; engine oil can be effectively controlled to move upwards when the bus brakes and idles, and oil leakage of an air compressor is reduced.

Description

Technical Field

[0001] The utility model relates to the field of air compressors, in particular to an anti-oil-channeling piston ring group structure for a city bus brake air compressor. Background Art

[0002] When city buses are running, the engine frequently idles due to low speed, many city traffic signals, and bus stops. The cylinder leaks a lot when the engine is idling, and the gas leakage causes high crankcase pressure. The crankcase of the brake air compressor of city buses is generally connected to the lubrication system in the crankcase of the engine. The increase in the crankcase pressure of the engine causes the pressure in the brake air compressor to increase synchronously.

[0003] When the brake air compressor is sucking air under negative pressure, due to the high crankcase pressure, the splashing lubricating oil will be sucked back into the piston groove, causing the engine oil to rise.

[0004] The piston rings used in brake bus air compressors usually adopt straight-opening double-nose piston rings. Due to the low speed of the air compressor, they cannot effectively seal the high-pressure gas from the open end to the crankcase, nor can they effectively prevent the scraped lubricant from flowing upward from the open end to the top of the piston, causing oil leakage from the air compressor. Summary of the invention

[0005] Purpose of the utility model: In order to overcome the shortcomings of the background technology, the utility model seeks to protect an anti-oil-spurting piston ring group structure for a city bus brake air compressor, which can improve the pumping efficiency of city buses and reduce downward gas blowby; it can effectively control the upward oil blowby when the bus brakes and idles, and reduce oil blowby in the air compressor.

[0006] Technical solution: The utility model discloses an anti-oil-spilling piston ring group structure for a brake air compressor for urban buses, wherein a piston moves in a cylinder, the bottom of the cylinder is connected to a crankcase, an annular groove is provided on the outer wall of the piston, a piston ring is provided in the annular groove, an opening is provided in the circumference of the piston ring, and both ends of the opening are stepped to form a lap-jointed opening. When the piston ring is placed in the cylinder for operation, the opening is closed to form a bent closure, and an oil scraping notch groove is provided at the bottom of the outer circumference of the piston ring.

[0007] Furthermore, the oil scraping notch groove extends circumferentially from one side to the other side of the piston ring opening.

[0008] Furthermore, the extended start and end of the oil scraping notch groove are both spaced a certain distance from the opening to form a closed notch groove structure.

[0009] Beneficial effects: Compared with the prior art, the advantages of the utility model are:

[0010] 1. By changing the opening form of the piston ring, the straight opening is changed into a lapped opening. Under low speed conditions, the gas on the top of the piston can be effectively sealed to prevent the gas from flowing downward, causing the crankcase mixed gas pressure to increase;

[0011] 2. The closed scraper notch groove on the piston ring can effectively scrape off the excess lubricating oil on the inner wall of the cylinder, preventing the lubricating oil stored in the piston groove from rushing up to the top of the piston through the gap at the open end;

[0012] 3. During the suction stroke of the air compressor, this overlapping opening can effectively prevent the oil in the piston groove from flowing through the opening to the top of the piston and causing oil leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is the structural diagram of the piston ring of the utility model;

[0014] Figure 2 This is the effect diagram of the piston going down in the utility model;

[0015] Figure 3 This is the effect diagram of the piston moving upward in the utility model. DETAILED DESCRIPTION

[0016] like Figure 1-3 The illustrated city bus brake air compressor uses an anti-oil-slip piston ring assembly structure, in which a piston 1 moves in a cylinder 2, and the bottom of the cylinder 2 is connected to a crankcase.

[0017] The outer wall of the piston 1 is provided with an annular groove, in which a piston ring 3 is arranged. The piston ring 3 is provided with an opening in the circumference, and both ends of the opening are stepped to form an overlapping opening. When placed in the cylinder 2 for operation, the opening is closed to form a bent closure. An oil scraping notch groove 4 is provided at the bottom of the outer circumference of the piston ring 3.

[0018] The oil scraper notch groove 4 extends circumferentially from one side of the opening of the piston ring 3 to the other side, and the extension start and end are both spaced a certain distance from the opening to form a closed notch groove structure, isolating the inside of the oil scraper notch groove 4 from the opening.

[0019] like Figure 2 As shown, the piston moves downward, and the scraped lubricating oil cannot escape from the opening gap;

[0020] like Figure 3 As shown, the piston moves upward and the high-pressure gas cannot leak from the opening gap.

[0021] Due to the use of overlapping piston ring opening, a test was conducted in a bus brake air compressor factory, using a straight opening piston ring with a cylinder diameter of φ75 for comparison with the overlapping opening.

[0022] Straight opening:

[0023] The amount of oil discharged with gas is 0.1504g / h (grams / hour);

[0024] Downflow gas volume 10L / min (liters / minute);

[0025] Overlap opening:

[0026] Oil discharge with gas: 0.010 g / h (grams / hour);

[0027] The blowby gas volume is 4 L / min (liters / minute).

[0028] The vehicle has passed the test and meets the requirements for urban public transportation.

Claims

1. An anti-oil channeling piston ring assembly structure for a city bus brake air compressor, wherein a piston (1) moves in a cylinder (2), and the bottom of the cylinder (2) is connected to a crankcase, characterized in that: The outer wall of the piston (1) is provided with an annular groove, in which a piston ring (3) is arranged. The piston ring (3) is provided with an opening in the circumferential direction, and both ends of the opening are stepped to form an overlapping opening. When the piston ring (3) is placed in the cylinder (2) for operation, the opening is closed to form a bent closure. An oil scraping notch groove (4) is provided at the bottom of the outer circumference of the piston ring (3).

2. The anti-oil-channeling piston ring assembly structure for a city bus brake air compressor according to claim 1 is characterized in that: The oil scraping notch groove (4) extends circumferentially from one side of the opening of the piston ring (3) to the other side.

3. The anti-oil-channeling piston ring assembly structure for a city bus brake air compressor according to claim 1 is characterized in that: The extended start and end of the oil scraping notch groove (4) are both spaced a certain distance from the opening, forming a closed notch groove structure.

Images