Oil-free air compressor and automobile

Abstract

The present invention relates to the technical field of new energy vehicles, and in particular to an oil-free air compressor and a vehicle. An oil-free air compressor comprises a cylinder body, in which a primary compression chamber, a primary exhaust chamber and a high-pressure chamber are arranged; wherein the primary compression chamber and the primary exhaust chamber are coaxially arranged and parallel to the axis of the high-pressure chamber respectively; the sum of the axial length of the primary compression chamber and the axial length of the primary exhaust chamber is less than the axial length of the high-pressure chamber; and further comprises a first valve plate assembly, which is arranged between the primary compression chamber and the primary exhaust chamber, and a first one-way valve body is also arranged on the first valve plate assembly, and the first one-way valve body is used to unidirectionally conduct the primary compression chamber to the primary exhaust chamber. Compared with the prior art, the present invention shortens the stroke of the low-pressure piston assembly in the primary compression chamber by shortening the axial length of the primary compression chamber (low-pressure chamber) and the axial length of the low-pressure piston connecting rod assembly; therefore, the present invention solves the technical problem existing in the prior art: how to shorten the axial stroke of the low-pressure piston assembly.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and in particular to an oil-free air compressor and a vehicle. Background Art

[0002] Piston oil-free air compressors are used for air compression in new energy vehicles. The comparative document CN201822042980.8 discloses the structure of an on-board electrically driven oil-free air compressor used in new energy vehicles. The oil-free air compressor includes a cylinder body, a low-pressure chamber is provided in the cylinder body, a low-pressure piston assembly is provided in the low-pressure chamber, and the low-pressure piston assembly reciprocates in the low-pressure chamber, thereby compressing the air entering the low-pressure chamber.

[0003] Generally, the axial stroke of the low-pressure piston assembly in the low-pressure chamber directly affects the surface treatment area of ​​the inner wall of the low-pressure chamber, thereby affecting the processing cost of the piston cylinder.

[0004] Specifically, in the prior art, the low-pressure piston assembly needs to move from the lowest end of the low-pressure chamber to the top of the low-pressure chamber to complete an air compression process, that is, the axial stroke of the low-pressure piston assembly in the low-pressure chamber is the axial length of the low-pressure chamber; this results in that, when the diameter of the low-pressure chamber is determined, the length of the low-pressure chamber in sliding contact with the low-pressure piston assembly is the overall axial length of the low-pressure chamber; the diameter of the low-pressure chamber is D, and the overall axial length of the low-pressure chamber is L, then the area of ​​the inner wall of the low-pressure chamber that requires surface treatment is equal to πDL; the so-called surface treatment is to use specific process means to improve the wear resistance, temperature resistance, corrosion resistance, and reduce the friction coefficient of the inner wall of the low-pressure chamber; therefore, the larger the surface treatment area of ​​the inner wall of the low-pressure chamber, the higher the processing cost of the piston cylinder.

[0005] In summary, in order to reduce the processing cost of the piston cylinder, the surface treatment area of ​​the inner wall of the low-pressure chamber needs to be reduced. Ultimately, the axial stroke of the low-pressure piston assembly in the low-pressure chamber needs to be reduced.

[0006] Therefore, a technical problem existing in the prior art is how to shorten the axial stroke of the low-pressure piston assembly. Summary of the invention

[0007] In view of the technical problem of how to shorten the axial stroke of a low-pressure piston assembly in the prior art, the present invention provides an oil-free air compressor and a vehicle.

[0008] The present invention is achieved through the following technical solutions:

[0009] An oil-free air compressor comprises a cylinder body, wherein a first-stage compression chamber, a first-stage exhaust chamber and a high-pressure chamber are arranged in the cylinder body;

[0010] The first-stage compression chamber and the first-stage exhaust chamber are coaxially arranged and parallel to the axis of the high-pressure chamber respectively; the sum of the axial length of the first-stage compression chamber and the axial length of the first-stage exhaust chamber is smaller than the axial length of the high-pressure chamber;

[0011] It also includes a first valve plate assembly, which is arranged between the first-stage compression chamber and the first-stage exhaust chamber, and a first one-way valve body is also arranged on the first valve plate assembly, and the first one-way valve body is used to unidirectionally conduct the first-stage compression chamber to the first-stage exhaust chamber;

[0012] It also includes a box body, which is located below the cylinder body and connected to the cylinder body;

[0013] It also includes a crankshaft assembly, a low-pressure connecting rod, and a low-pressure piston assembly. The crankshaft assembly is arranged in the casing, and the first-stage compression chamber is located between the first-stage exhaust chamber and the crankshaft assembly; the low-pressure piston assembly is movably arranged in the first-stage compression chamber and connected to the crankshaft assembly through the low-pressure connecting rod;

[0014] It also includes a high-pressure connecting rod and a high-pressure piston assembly; the high-pressure piston assembly is movably arranged in the high-pressure chamber and is connected to the crankshaft assembly through the high-pressure connecting rod;

[0015] Along the axial direction of the primary compression chamber and the primary exhaust chamber, the direction from the primary compression chamber to the primary exhaust chamber is upward, and the opposite direction is downward;

[0016] The top dead center of the high-pressure piston assembly is located above the first valve plate assembly, and the top dead center of the low-pressure piston assembly is located below the first valve plate assembly.

[0017] Furthermore, it also includes an intercooler valve plate and a cylinder head, wherein the combination of the intercooler valve plate and the cylinder head is covered on the cylinder body, and the intercooler valve plate is located between the cylinder head and the cylinder body;

[0018] The cylinder head and the intercooler valve plate jointly restrict and form a secondary exhaust chamber; a second one-way valve body is arranged on the intercooler valve plate, and the second one-way valve body can conduct the high-pressure chamber to the secondary exhaust chamber in a one-way manner;

[0019] Noise reduction ribs are also arranged in the secondary exhaust chamber, and extend along the axial direction of the primary compression chamber. One end of the noise reduction ribs is connected to the inner wall of the secondary exhaust chamber, and the other end does not contact any inner wall of the secondary exhaust chamber.

[0020] Furthermore, there are multiple noise reduction ribs, and the multiple noise reduction ribs are arranged parallel to each other and at intervals.

[0021] Furthermore, it also includes an intercooler, which is used to drive the air outside the oil-free air compressor to flow and form cooling wind;

[0022] It also includes a first blowing channel, which is used to convey part of the cooling air;

[0023] A first air duct is arranged in the side wall of the cylinder body, a second through hole is arranged in the intercooler valve plate, a second air duct is arranged in the cylinder head, and the second air duct forms a first air outlet on the surface of the cylinder head;

[0024] The first air duct, the second through hole, the second air duct and the first blowing port are respectively components of the first blowing channel.

[0025] Furthermore, heat dissipation ribs are arranged on the outer surface of the cylinder head, and the first air outlet is arranged toward the heat dissipation ribs.

[0026] Furthermore, a second blowing channel is provided, one end of which is connected to the first air duct, and the other end of which intersects with the side wall of the cylinder cover to form a second blowing port.

[0027] Furthermore, the box body is provided with an opening;

[0028] It also includes a steel sleeve and a bearing, both of which are arranged in the housing, and the steel sleeve is located between the bearing and the housing along the radial direction of the bearing; the crankshaft assembly is rotatably connected to the steel sleeve through the bearing;

[0029] It also includes a connecting piece and a foot pad. One end of the connecting piece is connected to the steel sleeve, and the other end passes through the opening of the box body and is connected to the foot pad.

[0030] Furthermore, a first slot is provided on the outer ring surface of the bearing, and a first engaging hole is provided on the steel sleeve; and a engaging member is also included, one end of the engaging member is inserted into the first engaging hole, and the other end is engaged in the first slot.

[0031] Furthermore, the number of openings, the number of connectors, and the number of foot pads are all the same.

[0032] A car is also provided, which comprises the above-mentioned oil-free air compressor.

[0033] Compared with the prior art, the advantages of the present invention are:

[0034] 1. In the present invention, the sum of the axial length of the primary compression chamber and the axial length of the primary exhaust chamber is less than the axial length of the high-pressure chamber, thereby making the axial length of the primary compression chamber (low-pressure chamber) of the present invention smaller than the axial length of the low-pressure chamber in the prior art; in the present invention, the top dead center of the high-pressure piston assembly is located above the first valve plate assembly, and the top dead center of the movement of the low-pressure piston assembly is located below the first valve plate assembly, thereby making the axial length of the low-pressure piston connecting rod assembly of the present invention smaller than the axial length of the low-pressure piston connecting rod assembly in the prior art, so as to match the primary compression chamber of the present invention with a smaller axial length than that of the prior art; in the present invention, the maximum stroke of the axial movement of the low-pressure piston assembly is the axial length of the primary compression chamber; compared with the prior art, the present invention shortens the stroke of the low-pressure piston assembly in the primary compression chamber by shortening the axial length of the primary compression chamber (low-pressure chamber) and the axial length of the low-pressure piston connecting rod assembly; therefore, the present invention solves the technical problem existing in the prior art: how to shorten the axial stroke of the low-pressure piston assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a structural schematic diagram of the cylinder body in Example 1;

[0036] Figure 2 for Figure 1 A schematic diagram of the structure of the first one-way valve body;

[0037] Figure 3 It is a structural cross-sectional view of the oil-free air compressor in Example 1;

[0038] Figure 4 It is a structural schematic diagram of the cylinder body from another perspective;

[0039] Figure 5 It is a structural schematic diagram of the intercooler valve plate of the present invention;

[0040] Figure 6 It is a schematic diagram of a partial cross-section of a cylinder head of the present invention;

[0041] Figure 7 It is a schematic diagram of the back side of the cylinder head of the present invention;

[0042] Figure 8 It is a structural schematic diagram of the steel sleeve of the present invention;

[0043] Fig. 9 It is a structural schematic diagram of the bearing of the present invention.

[0044] Markings in the figure: cylinder body (1), first valve plate assembly (3), first one-way channel (301), first compression chamber (4), first exhaust chamber (5), first one-way valve body (6), fixed shaft (601), elastic sheet (602), low-pressure piston assembly (7), high-pressure chamber (8), high-pressure piston assembly (9), intercooler valve plate (10), cylinder head (11), second exhaust chamber (12), second one-way valve body (13), noise reduction rib (14), intercooler (15), first air duct (16), second through hole (17), second air duct (18), first air outlet (19), heat dissipation rib (20), a second air blowing channel (22), a crankshaft assembly (23), a high-pressure connecting rod (24), a low-pressure connecting rod (25), a housing (26), an opening (27), a steel sleeve (28), a bearing (29), a connecting piece (30), a foot pad (31), a first air port (32), a second air port (33), a first clamping groove (34), a clamping piece (35), a heat-conducting rib (36), a first-stage air intake valve plate (37), a motor (38), a plum blossom-shaped elastic coupling (39), a flywheel (40), a crankshaft (41), a balancing block (42), a first clamping hole (43), and a dust collecting groove (44). DETAILED DESCRIPTION

[0045] The following is a further non-restrictive detailed description of the technical solution of the invention in conjunction with the preferred embodiments and the accompanying drawings. In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings. In addition, the terms "first" and "second" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and cannot be understood as limitations on the present invention. Example 1

[0046] like Figure 1 to Figure 3As shown, this embodiment proposes an oil-free air compressor, which includes a cylinder body 1, in which a first-stage compression chamber 4, a first-stage exhaust chamber 5 and a high-pressure chamber 8 are arranged; wherein the first-stage compression chamber 4 and the first-stage exhaust chamber 5 are coaxially arranged and parallel to the axis of the high-pressure chamber 8 respectively; the sum of the axial length of the first-stage compression chamber 4 and the axial length of the first-stage exhaust chamber 5 is less than the axial length of the high-pressure chamber 8; it also includes a first valve plate assembly 3, the first valve plate assembly 3 is arranged between the first-stage compression chamber 4 and the first-stage exhaust chamber 5, and a first check valve body 6 is also arranged on the first valve plate assembly 3, and the first check valve body 6 is used to unidirectionally conduct the first-stage compression chamber 4 to the first-stage exhaust chamber 5; it also includes a box body 26, which is located below the cylinder body 1 and connected to the cylinder body 1; it also includes a crankshaft assembly 23, a low-pressure connection The rod 25, the low-pressure piston assembly 7, and the crankshaft assembly 23 are arranged in the box body 26, and the primary compression chamber 4 is located between the primary exhaust chamber 5 and the crankshaft assembly 23; the low-pressure piston assembly 7 is movably arranged in the primary compression chamber 4, and is connected to the crankshaft of the crankshaft assembly 23 through the low-pressure connecting rod 25; it also includes a high-pressure connecting rod 24 and a high-pressure piston assembly 9; the high-pressure piston assembly 9 is movably arranged in the high-pressure chamber 8, and is connected to the crankshaft assembly 23 through the high-pressure connecting rod 24; along the axial direction of the primary compression chamber 4 and the primary exhaust chamber 5, the direction from the primary compression chamber 4 to the primary exhaust chamber 5 is upward, and vice versa is downward; the top dead center of the high-pressure piston assembly 9 is located above the first valve plate assembly 3, and the top dead center of the low-pressure piston assembly 7 is located below the first valve plate assembly 3.

[0047] The cylinder body 1 is made of metal; the cylinder body 1 can be formed into a first-stage compression chamber 4, a first-stage exhaust chamber 5, and a first valve plate assembly 3 by machining.

[0048] A first one-way valve body 6 is disposed on the first valve plate assembly 3 , and the first-stage compression chamber 4 and the first-stage exhaust chamber 5 can be unidirectionally communicated through the first one-way valve body 6 . When the gas flows, it flows unidirectionally from the first-stage compression chamber 4 to the first-stage exhaust chamber 5 .

[0049] Combination Figure 1 to Figure 3Specifically, a first one-way channel 301 is provided on the first valve plate assembly 3, one end of the first one-way channel 301 is connected to the first-stage compression chamber 4, and the other end is connected to the first-stage exhaust chamber 5. The first one-way valve body 6 includes a fixed shaft 601 and an elastic sheet 602. Along the axial direction of the first-stage exhaust chamber 5, the first one-way channel 301 corresponds to the edge of the elastic sheet 602. When the gas is compressed in the first-stage compression chamber 4 and the pressure of the gas reaches a certain value, the gas acts on the edge of the elastic sheet 602 through the first one-way channel 301, so that the edge of the elastic sheet 602 is tilted in the direction away from the first valve plate assembly 3, and the edge of the elastic sheet 602 does not block the first one-way channel 301, so that the first-stage compression chamber 4 and the first-stage exhaust chamber 5 are connected to each other through the first one-way channel 301. In other cases, for example, when the gas pressure is insufficient to push the edge of the elastic sheet 602 upward in a direction away from the first valve plate assembly 3, or when the low-pressure piston assembly 7 moves downward and negative pressure is generated in the first compression chamber 4, the edge of the elastic sheet 602 swings toward the direction of the first valve plate assembly 3, and the edge of the elastic sheet 602 blocks the first one-way channel 301, and the first compression chamber 4 and the first exhaust chamber 5 are cut off.

[0050] The primary compression chamber 4 is also called the low-pressure chamber, and the low-pressure piston assembly 7 is confined in the primary compression chamber 4.

[0051] The high-pressure chamber 8 is also called the secondary compression chamber; the size and dimensions of the high-pressure chamber 8 are consistent with those in the prior art. There are many ways to process the high-pressure chamber 8. For example, the high-pressure chamber 8 penetrates the cylinder body 1 from top to bottom, and forms a primary opening and a secondary opening on the upper and lower surfaces of the cylinder body 1, respectively. The air compressed by the low-pressure piston assembly 7 in the primary compression chamber 4 is further transported to the high-pressure chamber 8, i.e., the secondary compression chamber, and is compressed by the high-pressure piston assembly 9 for the secondary stage.

[0052] On the premise that the axial length of the high-pressure chamber 8 of the present embodiment is equal to the axial length of the high-pressure chamber of the prior art, in the prior art, the axial length of the low-pressure chamber is consistent with the axial length of the high-pressure chamber; in the present embodiment, the sum of the axial length of the first-stage compression chamber 4 and the axial length of the first-stage exhaust chamber 5 is smaller than the axial length of the high-pressure chamber 8. Therefore, the axial length of the first-stage compression chamber 4, that is, the low-pressure chamber, of the present embodiment is smaller than the axial length of the high-pressure chamber 8; therefore, it can be meaninglessly deduced that the axial length of the first-stage compression chamber 4 (low-pressure chamber) of the present embodiment is smaller than the axial length of the low-pressure chamber of the prior art.

[0053] The structures of the low-pressure piston assembly 7 and the high-pressure piston assembly 9 are consistent with those in the prior art and will not be described in detail herein.

[0054] In this embodiment, the combination of the low-pressure piston assembly 7 and the low-pressure connecting rod 25 is a low-pressure piston-connecting rod assembly, and the combination of the high-pressure piston assembly 9 and the high-pressure connecting rod 24 is a high-pressure piston-connecting rod assembly.

[0055] As can be seen from the foregoing, the present embodiment shortens the axial length of the primary compression chamber 4 (low-pressure chamber). If the low-pressure piston connecting rod assembly in the prior art is still used to connect to the crankshaft assembly, insufficient axial space in the cylinder body will occur. Therefore, in the present embodiment, in order to match, the primary compression chamber 4 with a smaller axial length has a further shortened axial length of the low-pressure piston connecting rod assembly relative to the prior art.

[0056] Specifically, in this embodiment, it is proposed that: the top dead center of the high-pressure piston assembly 9 is located above the first valve plate assembly 3, and the top dead center of the low-pressure piston assembly 7 is located below the first valve plate assembly 3; and the high-pressure connecting rod 24 and the low-pressure connecting rod 25 are both connected to the same crankshaft assembly 23, so it can be concluded that:

[0057] On the premise that the axial length of the high-pressure piston connecting rod assembly of the present application is consistent with the axial length of the high-pressure piston connecting rod assembly in the prior art; in the prior art, the axial length of the low-pressure piston connecting rod assembly is consistent with the axial length of the high-pressure piston connecting rod assembly; in the present embodiment, since the top dead center of the high-pressure piston assembly 9 is located above the top dead center of the low-pressure piston assembly 7, that is, the top dead center of the high-pressure piston connecting rod assembly is located above the top dead center of the low-pressure piston connecting rod assembly, since the high-pressure piston connecting rod assembly and the low-pressure piston connecting rod assembly are both connected to the same crankshaft assembly 23, the axial length of the low-pressure piston connecting rod assembly of the present embodiment is smaller than the axial length of the high-pressure piston connecting rod assembly; therefore, it can be concluded meaninglessly that the axial length of the low-pressure piston connecting rod assembly of the present embodiment is smaller than the axial length of the low-pressure piston connecting rod assembly in the prior art.

[0058] In summary, compared with the prior art, this embodiment not only shortens the axial length of the first-stage compression chamber 4, but also shortens the axial length of the low-pressure piston connecting rod assembly.

[0059] As can be seen from the background technology, the technical problem existing in the prior art of this embodiment is how to shorten the axial stroke of the low-pressure piston assembly.

[0060] In this embodiment, the sum of the axial length of the primary compression chamber 4 and the axial length of the primary exhaust chamber 5 is less than the axial length of the high-pressure chamber 8, thereby making the axial length of the primary compression chamber 4 (low-pressure chamber) of this embodiment smaller than the axial length of the low-pressure chamber in the prior art; in this embodiment, the top dead center of the high-pressure piston assembly 9 is located above the first valve plate assembly 3, and the top dead center of the movement of the low-pressure piston assembly 7 is located below the first valve plate assembly 3, thereby making the axial length of the low-pressure piston connecting rod assembly of this embodiment smaller than the axial length of the low-pressure piston connecting rod assembly in the prior art, so as to match the primary compression chamber 4 in this embodiment with a smaller axial length than that in the prior art; in this embodiment, the maximum stroke of the axial movement of the low-pressure piston assembly 7 is the axial length of the primary compression chamber 4; compared with the prior art, this embodiment shortens the stroke of the low-pressure piston assembly 7 in the primary compression chamber 4 by shortening the axial length of the primary compression chamber 4 (low-pressure chamber) and the axial length of the low-pressure piston connecting rod assembly; therefore, this embodiment solves the technical problem existing in the prior art: how to shorten the axial stroke of the low-pressure piston assembly.

[0061] Furthermore, since the axial length of the first-stage compression chamber 4 (low-pressure chamber) is shortened in this embodiment, when the diameter of the first-stage compression chamber 4 (low-pressure chamber) in this embodiment is consistent with the diameter of the low-pressure chamber in the prior art, the inner wall surface treatment area of ​​the first-stage compression chamber 4 in this embodiment is smaller, thereby saving processing costs.

[0062] Furthermore, in the present embodiment, the low-pressure piston assembly 7 moves only in the first-stage compression chamber 4. The low-pressure piston assembly 7 has the characteristics of large diameter and heavy weight. Compared with the prior art, the top dead point of the movement of the low-pressure piston assembly 7 in the present embodiment is lower and the center of gravity is lower; therefore, this leads to the oil-free air compressor using the present embodiment having a lower center of gravity compared with the prior art, and the oil-free air compressor with a lower center of gravity runs more smoothly.

[0063] Compressed air, referred to as compressed air, has a large amount of energy due to multiple times of work being done on it. During the transmission of compressed air, compressed air is prone to collide with the inner wall of the transmission channel to produce pulsating noise. Usually, the oil-free air compressor is arranged on the vehicle chassis, and the cab is located on the upper side of the oil-free air compressor. The pulsating noise transmitted by compressed air will seriously affect the comfort of the entire vehicle and it is difficult to meet the vehicle NVH requirements.

[0064] How to reduce the pulsation noise of compressed air is a technical problem that needs to be solved. This technical problem is solved by the following technical solution.

[0065] like Figure 3 to Figure 5As shown, further, the oil-free air compressor of this embodiment also includes an intercooler valve plate 10 and a cylinder head 11, the combination of the intercooler valve plate 10 and the cylinder head 11 is covered on the cylinder body 1, and the intercooler valve plate 10 is located between the cylinder head 11 and the cylinder body 1; the cylinder head 11 and the intercooler valve plate 10 jointly limit and form a secondary exhaust chamber 12; a second one-way valve body 13 is provided on the intercooler valve plate 10, and the second one-way valve body 13 can unidirectionally conduct the high-pressure chamber 8 toward the secondary exhaust chamber 12; a noise reduction rib 14 is also provided in the secondary exhaust chamber 12, and the noise reduction rib 14 extends along the axial direction of the primary compression chamber 4, one end of the noise reduction rib 14 is connected to the inner wall of the secondary exhaust chamber 12, and the other end does not contact all the inner walls of the secondary exhaust chamber 12.

[0066] The noise reduction ribs 14 can be made of metal materials or other materials. Preferably, the material of the noise reduction ribs 14 in this embodiment is consistent with the material of the cylinder head 11. The noise reduction ribs 14 can be processed by machining or integral casting. Preferably, there are multiple noise reduction ribs 14, and the multiple noise reduction ribs 14 are arranged in parallel and at intervals.

[0067] The structure and principle of the second one-way valve body 13 are similar to those of the first one-way valve body 6, and will not be described in detail. In this embodiment, the gas circulates in one direction in the order of the first compression chamber 4, the first exhaust chamber 5, the high pressure chamber 8, and the second exhaust chamber 12.

[0068] The advantages of this solution are as follows:

[0069] First, in this embodiment, due to the setting of the noise reduction ribs 14, when the compressed air passes through the secondary exhaust chamber 12, on the one hand, the pulsation energy of the gas is absorbed by the noise reduction ribs 14 and transmitted to the cylinder head 11, and on the other hand, the pulsation energy of the gas is blocked and attenuated by the noise reduction ribs 14; this embodiment achieves the effect of reducing the pulsation energy of the gas through the noise reduction ribs 14, thereby reducing the pulsation noise of the gas.

[0070] Second, in the original prior art, it is necessary to set up space for a primary exhaust chamber and a secondary exhaust chamber in the cylinder head at the same time. In this embodiment, the primary exhaust chamber originally set in the cylinder head in the prior art is set in the cylinder body 1. It can be understood that in this embodiment, only the secondary exhaust chamber 12 is required to be set in the cylinder head 11; therefore, in this embodiment, the secondary exhaust chamber 12 can occupy as much of the internal space of the cylinder head 11 as possible, so that the volume of the secondary exhaust chamber 12 of this embodiment is larger than that of the secondary exhaust chamber of the prior art; further, the noise reduction rib 14 can be set thinner, so that the cavity volume of the secondary exhaust chamber 12 is larger; and if the volume of the secondary exhaust chamber 12 of this embodiment is larger than that of the prior art, then after the gas with pulsating energy enters the secondary exhaust chamber 12, the volume occupied in the secondary exhaust chamber 12 is smaller, and the air flow fluctuation inside the secondary exhaust chamber 12 is smaller, which is more helpful to reduce the gas pulsation noise.

[0071] Third, in this embodiment, the first-stage compression chamber 4, the first-stage exhaust chamber 5, and the second-stage exhaust chamber 12 are arranged in a gradient from bottom to top, with a compact structure and reasonable use of space; in addition, it can also play a role in reducing mechanical noise. Specifically, the noise of the crankshaft assembly 23 in the air compressor is mechanical noise. In the process of mechanical noise being transmitted from bottom to top, it will pass through the first-stage compression chamber 4, the first-stage exhaust chamber 5, and the second-stage exhaust chamber 12 in sequence, and these three chambers are filled with air respectively, which has the function of attenuating and reducing noise. The principle is that 1. Air is a good sound-absorbing material, which can absorb part of the energy of noise. When the noise is transmitted to the chamber through the air, the air damping effect between air molecules will gradually weaken the noise energy; 2. When the noise is transmitted to the inside of the chamber, part of the noise will be absorbed by the chamber wall material, and the remaining noise will cause the air in the chamber to vibrate. This vibration will hit the inner wall of the chamber and be blocked by the inner wall of the chamber, thereby reducing the noise; therefore, this embodiment can also play a role in reducing mechanical noise from bottom to top.

[0072] Fourth, the oil-free air compressor is usually arranged on the vehicle chassis, located below the cab. This embodiment reduces the gas pulsation noise and mechanical noise of the oil-free air compressor, and further improves the driving comfort of the driver.

[0073] Furthermore, the low-pressure piston assembly 7 has a first-stage intake valve plate 37, and the structure and setting method of the first-stage intake valve plate 37 are all prior arts, see the contents disclosed in patent document CN201822042980.8.

[0074] Furthermore, the oil-free air compressor of this embodiment also includes a motor 38, a crankshaft assembly 23, a plum blossom-type elastic coupling 39, and a flywheel 40; wherein the crankshaft assembly 23 includes a crankshaft 41 and two balancing blocks 42, the crankshaft 41 is a crankshaft structure of a two-half combined opposing structure, and the two balancing blocks 42 are respectively arranged on both sides of the crankshaft 41; the motor 38 is arranged on one side of the crankshaft assembly 23, facing a balancing block 42 of the motor 38, and is connected to the main shaft of the motor 38 through the plum blossom-type elastic coupling 39 and the flywheel 40; further, the high-pressure piston assembly 9 is connected to the crankshaft 41 through the high-pressure connecting rod 24, and the low-pressure piston assembly 7 is connected to the crankshaft 41 through the low-pressure connecting rod 25.

[0075] Further, such as Figure 3 As shown, the oil-free air compressor also includes an intercooler 15, which includes an intercooler channel and a fan for cooling the intercooler channel; wherein the intercooler channel is used to transport compressed air, and the two ends of the intercooler channel are respectively a cooling inlet and a cooling outlet; the rotation of the fan drives the surrounding air outside the air compressor to form cooling wind, and is used to cool the intercooler channel.

[0076] like Figure 3-4 As shown, a first connecting channel and a second connecting channel are further provided in the cylinder body 1 of the oil-free air compressor of this embodiment, wherein one end of the first connecting channel is connected to the cooling inlet of the intercooling channel, and the other end intersects at the upper surface of the cylinder body 1 to form a first air port 32, and one end of the second connecting channel is connected to the cooling outlet of the intercooling channel, and the other end intersects at the upper surface of the cylinder body 1 to form a second air port 33.

[0077] When in use, the motor 38 provides a power source, which drives the crankshaft 41 to rotate through the flywheel 40 and the plum blossom-shaped elastic coupling 39, thereby realizing the alternating reciprocating motion of the low-pressure piston assembly 7 and the high-pressure piston assembly 9, so that the volume of the primary compression chamber 4 and the high-pressure chamber 8 (secondary compression chamber) changes periodically to achieve the purpose of compressing air.

[0078] The low-pressure piston assembly 7 moves from the top dead center to the bottom dead center, and negative pressure is generated in the primary compression chamber 4. The gas is sucked into the primary compression chamber 4 from the primary intake valve plate 37 of the low-pressure piston assembly 7; the low-pressure piston assembly 7 moves from the bottom dead center to the top dead center, and the gas in the primary compression chamber 4 is squeezed, and the gas pressure increases. The gas passes through the first one-way valve body 6 and enters the primary exhaust chamber 5. At this time, a compression of the gas is completed; at this time, the pressure of the gas is relatively low and the temperature is relatively high. Subsequently, the gas passes through the first gas port 32 and the first connecting channel, enters the intercooling channel, and is cooled by the fan, and is then transported to the second gas port 33 through the second connecting channel.

[0079] Subsequently, the high-pressure piston assembly 9 moves from the top dead center to the bottom dead center, and the high-pressure chamber 8 (secondary compression chamber) generates negative pressure, and the gas is sucked into the high-pressure chamber 8. When the high-pressure piston assembly 9 moves from the bottom dead center to the top dead center, the gas in the high-pressure chamber 8 is squeezed again, and the gas pressure increases. The gas passes through the second one-way valve body 13 and enters the secondary exhaust chamber 12. At this time, the second compression of the gas is completed. As the piston reciprocates, the above process is repeated, and the gas is continuously compressed and discharged.

[0080] The combination of the cylinder block 1, the intercooler valve plate 10 and the cylinder head 11 forms a cylinder head. As can be seen from the foregoing content, compressed air with a relatively high temperature will flow in the cylinder head. How to cool the cylinder head is a technical problem that needs to be solved. This technical problem is solved by the following technical solution.

[0081] like Figure 3 to Figure 7 As shown, the oil-free air compressor of this embodiment also includes a first blowing channel, which is used to transport part of the cooling air driven by the fan of the intercooler 15; a first air duct 16 is arranged in the side wall of the cylinder body 1, a second through hole 17 is arranged in the intercooler valve plate 10, a second air duct 18 is arranged in the cylinder head 11, and the second air duct 18 forms a first blowing port 19 on the surface of the cylinder head 11; the first air duct 16, the second through hole 17, the second air duct 18, and the first blowing port 19 are respectively components of the first blowing channel.

[0082] When in use, a portion of the cooling air driven by the fan of the intercooler 15 passes through the first air duct 16, the second through hole 17, and the second air duct 18 in sequence, and is finally blown out from the first blowing port 19. The cooling air in the first blowing channel takes away the heat in the first blowing channel during the flow, including the heat of the channel inner wall of the first air duct 16 arranged in the cylinder body 1, the heat of the through hole inner wall of the second through hole 17 arranged in the intercooler valve plate 10, and the heat of the channel inner wall of the second air duct 18 arranged in the cylinder head 11; thereby achieving the purpose of cooling the cylinder body 1, the intercooler valve plate 10, and the cylinder head 11, that is, the purpose of cooling the cylinder head.

[0083] Preferably, a plurality of heat-conducting ribs 36 are provided in the second through hole 17, and the plurality of heat-conducting ribs 36 are arranged at intervals from each other and are respectively connected to the hole walls of the second through hole 17; the purpose is to increase the contact area between the intercooler valve plate 10 and the cooling air, so that the heat exchange efficiency between the intercooler valve plate 10 and the cooling air is higher.

[0084] Further preferably, a heat dissipation rib 20 is provided on the outer surface of the cylinder head 11, and the first air outlet 19 is provided toward the heat dissipation rib 20. The cooling air blown out from the first air outlet 19 continues to blow toward the heat dissipation rib 20 on the outer surface of the cylinder head 11, and then takes away the heat of the cylinder head 11 through the heat dissipation rib 20. The provision of the heat dissipation rib 20 increases the heat exchange efficiency between the cooling air and the cylinder head 11, and serves the purpose of further cooling the surface of the cylinder head 11.

[0085] Further, such as Figure 3-4 As shown, the oil-free air compressor of this embodiment is further provided with a second blowing channel 22, one end of the second blowing channel 22 is connected to the first air duct 16, and the other end intersects with the side wall of the cylinder head 11 to form a second blowing port.

[0086] In this embodiment, a portion of cooling air is diverted from the first air duct 16 and blown out from the second air outlet on the side wall of the cylinder head 11 through the second air blowing channel 22 to achieve the purpose of cooling the side wall of the cylinder head 11 .

[0087] Furthermore, in the prior art, the crankshaft assembly is directly connected to the air compressor case through a bearing. The downward force generated by the overall weight of the crankshaft assembly, the low-pressure piston assembly, and the high-pressure piston assembly, as well as the torque of the movement of the high- and low-pressure piston assemblies, are all transmitted to the air compressor case. In order to meet the requirement of lightweight of the entire machine, the air compressor case is usually made of aluminum material. As a result, during long-term use, the air compressor casing will be deformed or broken due to the long-term effect of the above-mentioned forces and torques. Therefore, in order to extend the service life of the air compressor casing, the present embodiment also includes the following technical solutions.

[0088] like Figure 3 , Figure 8 As shown, the housing 26 is provided with an opening 27; it also includes a steel sleeve 28 and a bearing 29, both of which are arranged in the housing 26, and along the radial direction of the bearing 29, the steel sleeve 28 is located between the bearing 29 and the housing 26; the crankshaft assembly 23 is rotatably connected to the steel sleeve 28 through the bearing 29; it also includes a connecting piece 30 and a foot pad 31, one end of the connecting piece 30 is connected to the steel sleeve 28, and the other end passes through the opening 27 of the housing 26 and is connected to the foot pad 31.

[0089] Among them, the number of openings 27, the number of connectors 30, and the number of foot pads 31 are all the same, that is, the number of openings 27 matches the number of connectors 30 and the number of foot pads 31, respectively. For example, in this embodiment, two openings 27 are respectively set on both sides of the box body 26, and the number of connectors 30 and the number of foot pads 31 are also two, respectively. One end of one connector 30 passes through an opening 27 and is connected to a foot pad 31, and one end of the other connector 30 passes through the other opening 27 and is connected to the other foot pad 31.

[0090] The connecting member 30 may be a plate structure made of metal.

[0091] In this embodiment, the crankshaft assembly 23 is connected to the steel sleeve 28 through the bearing 29, and the steel sleeve 28 is connected to the foot pad 31 through the connecting piece 30, so that the downward force generated by the overall weight of the crankshaft assembly 23, the low-pressure piston assembly 7, and the high-pressure piston assembly 9, as well as the torque of the movement of the low-pressure piston assembly 7 and the high-pressure piston assembly 9 are transmitted to the foot pad 31 through the bearing 29, the steel sleeve 28, and the connecting piece 30, thereby transferring most of the force and torque originally acting on the air compressor case 26, reducing the force and torque on the air compressor case 26, and effectively extending the service life of the air compressor case 26.

[0092] Furthermore, in the prior art, the crankshaft assembly is directly connected to the housing through bearings. During the operation of the air compressor, due to mechanical friction and the work done by the compressed gas, a large amount of heat will be generated in the housing, causing the housing temperature to rise. The housing is made of aluminum, and the crankshaft assembly, bearings, etc. are all made of steel. The thermal expansion coefficient of aluminum is larger than that of steel, which results in the expansion of the crankshaft along the bearing when heated. Figure 3 From top to bottom, which is one of the radial directions of the bearing, the expansion and deformation degrees of the housing, crankshaft assembly and bearing are different. The expansion and deformation of the housing is greater, resulting in a larger gap between the housing and the bearing, downward movement of the bearing, and downward movement of the crankshaft assembly connected to the bearing.

[0093] In this embodiment, a steel sleeve 28 made of steel is arranged between the bearing 29 and the housing 26, that is, the outer ring of the bearing 29 is fixed to the steel sleeve 28, and the steel sleeve 28 is made of the same material as the crankshaft assembly 23 and the bearing 29; a large amount of heat will be generated in the housing 26, and in the process of the housing temperature rising, the heat will be generated along the Figure 3 In the direction from top to bottom, that is, one of the radial directions of the bearing 29, the degree of thermal expansion deformation and the amount of thermal expansion of the bearing 29 and the steel sleeve 28 are consistent, and there is no gap between the outer ring of the bearing 29 and the steel sleeve 28, thereby avoiding the downward movement of the bearing 29 and the downward movement of the crankshaft assembly 23 connected to the bearing 29.

[0094] Further, such as Figure 3 , Fig. 9 As shown, in this embodiment, a first slot 34 is provided on the outer ring surface of the bearing 29 , and a first engaging hole 43 is provided on the steel sleeve 28 ; a engaging member 35 is also included, one end of the engaging member 35 is inserted into the first engaging hole 43 , and the other end is engaged in the first slot 34 .

[0095] The engaging member 35 can be selected as a screw, a bolt, a pin, a threaded bayonet, etc. Preferably, in order to increase the connection strength between the engaging member 35 and the first engaging hole 43, the engaging member 35 is a threaded bayonet, whose outer surface has a first external thread, and the hole wall of the first engaging hole 43 is processed with a first internal thread, and the engaging member 35 (i.e., the threaded bayonet) is threadedly matched with the first engaging hole 43 to be connected.

[0096] When the air compressor is started or stopped, the motor vibrates and impacts greatly. This vibration can easily cause circumferential displacement between the outer ring of the bearing 29 and the inner ring of the cylinder liner 28. This displacement is also called the slipping and creeping phenomenon of the bearing 29 relative to the cylinder liner 28. Over time, it can easily cause the outer ring of the bearing 29 to be worn by the inner ring of the cylinder liner 28.

[0097] In this embodiment, the outer ring of the bearing 29 is engaged and fixed with the inner ring of the steel sleeve 28 through the engagement of the engaging member 35 and the first engaging hole 43. Since the outer ring of the bearing 29 and the inner ring of the steel sleeve 28 are relatively fixed, the circumferential displacement between the outer ring of the bearing 29 and the inner ring of the steel sleeve 28 when the air compressor is started or stopped is avoided, thereby avoiding the slipping and creeping of the above-mentioned bearing 29 relative to the cylinder sleeve 28, and further avoiding the outer ring of the bearing 29 being worn by the inner ring of the cylinder sleeve 28.

[0098] Further, such as Figure 3 As shown, the inner wall of the housing 26 of the air compressor of this embodiment is also processed with a dust collecting groove 44, and the groove of the dust collecting groove 44 is arranged toward the crankshaft assembly 23. The dust collecting groove 44 is used to collect debris dropped from the power components in the housing 26 of the air compressor, such as the friction between the crankshaft 41 and the bearing connected to the crankshaft 41, resulting in debris falling from the surface of the crankshaft 41, and the debris dropped by the friction between the outer surface of the high-pressure piston assembly 9 and the inner wall of the high-pressure chamber 8, and the debris dropped by the friction between the outer surface of the low-pressure piston assembly 7 and the inner wall of the first-stage compression chamber 4, etc. Example 2

[0099] This embodiment provides a car, which includes the oil-free air compressor of embodiment 1.

[0100] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the attached claims.

Claims

1. Oil-free air compressor, characterized in that: It comprises a cylinder body (1), wherein a first-stage compression chamber (4), a first-stage exhaust chamber (5) and a high-pressure chamber (8) are arranged in the cylinder body (1); The first-stage compression chamber (4) and the first-stage exhaust chamber (5) are coaxially arranged and are respectively parallel to the axis of the high-pressure chamber (8); the sum of the axial length of the first-stage compression chamber (4) and the axial length of the first-stage exhaust chamber (5) is smaller than the axial length of the high-pressure chamber (8); It also comprises a first valve plate assembly (3), the first valve plate assembly (3) being arranged between the first-stage compression chamber (4) and the first-stage exhaust chamber (5), and a first one-way valve body (6) being arranged on the first valve plate assembly (3), the first one-way valve body (6) being used for unidirectionally conducting the first-stage compression chamber (4) toward the first-stage exhaust chamber (5); It also includes a box body (26), which is located below the cylinder body (1) and connected to the cylinder body (1); It also includes a crankshaft assembly (23), a low-pressure connecting rod (25), and a low-pressure piston assembly (7); the crankshaft assembly (23) is arranged in a housing (26); the first-stage compression chamber (4) is located between the first-stage exhaust chamber (5) and the crankshaft assembly (23); the low-pressure piston assembly (7) is movably arranged in the first-stage compression chamber (4) and is connected to the crankshaft assembly (23) via the low-pressure connecting rod (25); It also includes a high-pressure connecting rod (24) and a high-pressure piston assembly (9); the high-pressure piston assembly (9) is movably disposed in the high-pressure chamber (8) and is connected to the crankshaft assembly (23) via the high-pressure connecting rod (24); Along the axial direction of the first-stage compression chamber (4) and the first-stage exhaust chamber (5), the direction from the first-stage compression chamber (4) to the first-stage exhaust chamber (5) is upward, and the opposite direction is downward; The top dead center of the high-pressure piston assembly (9) is located above the first valve plate assembly (3), and the top dead center of the low-pressure piston assembly (7) is located below the first valve plate assembly (3); It also includes an intercooler valve plate (10) and a cylinder head (11), wherein the combination of the intercooler valve plate (10) and the cylinder head (11) is covered on the cylinder body (1), and the intercooler valve plate (10) is located between the cylinder head (11) and the cylinder body (1); The cylinder head (11) and the intercooler valve plate (10) jointly restrict and form a secondary exhaust chamber (12); a second one-way valve body (13) is provided on the intercooler valve plate (10), and the second one-way valve body (13) unidirectionally conducts the high-pressure chamber (8) toward the secondary exhaust chamber (12); A noise reduction rib (14) is also provided in the secondary exhaust chamber (12). The noise reduction rib (14) extends along the axial direction of the primary compression chamber (4). One end of the noise reduction rib (14) is connected to the inner wall of the secondary exhaust chamber (12), and the other end does not contact any inner wall of the secondary exhaust chamber (12). It also includes an intercooler (15), which is used to drive the air outside the oil-free air compressor to flow and form cooling air; It also includes a first blowing channel, which is used to convey part of the cooling air; A first air duct (16) is provided in the side wall of the cylinder body (1), a second through hole (17) is provided in the intercooler valve plate (10), a second air duct (18) is provided in the cylinder head (11), and the second air duct (18) forms a first air outlet (19) on the surface of the cylinder head (11); The first air duct (16), the second through hole (17), the second air duct (18), and the first air blowing port (19) are respectively components of the first air blowing channel; The box body (26) is provided with an opening (27); It also includes a steel sleeve (28) and a bearing (29), wherein the steel sleeve (28) and the bearing (29) are both arranged in the housing (26), and along the radial direction of the bearing (29), the steel sleeve (28) is located between the bearing (29) and the housing (26); the crankshaft assembly (23) is rotatably connected to the steel sleeve (28) via the bearing (29); It also includes a connecting piece (30) and a foot pad (31), wherein one end of the connecting piece (30) is connected to the steel sleeve (28), and the other end passes through the opening (27) of the box body (26) and is connected to the foot pad (31).

2. The oil-free air compressor according to claim 1, characterized in that: There are a plurality of noise reduction ribs (14), and the plurality of noise reduction ribs (14) are arranged parallel to each other and at intervals.

3. The oil-free air compressor according to claim 1, characterized in that: A heat dissipation rib (20) is provided on the outer surface of the cylinder cover (11), and the first air blowing port (19) is arranged toward the heat dissipation rib (20).

4. The oil-free air compressor according to claim 1, characterized in that: A second blowing channel (22) is also provided, one end of the second blowing channel (22) being connected to the first air duct (16), and the other end of the second blowing channel (22) intersecting with the side wall of the cylinder cover (11) to form a second blowing port.

5. The oil-free air compressor according to claim 1, characterized in that: The outer ring surface of the bearing (29) is provided with a first clamping groove (34), and the steel sleeve (28) is provided with a first clamping hole (43); and also includes a clamping member (35), one end of the clamping member (35) is inserted into the first clamping hole (43), and the other end is clamped into the first clamping groove (34).

6. The oil-free air compressor according to claim 1, characterized in that: The number of openings (27), the number of connecting pieces (30), and the number of foot pads (31) are all the same.

7. A car, characterized in that: The invention comprises the oil-free air compressor as described in any one of claims 1 to 6.

Images