Air compressor and vehicle

Abstract

The utility model relates to an air compressor and a vehicle. Wherein the air compressor comprises an air cylinder, a piston and a leather cup. The leather cup comprises a sealing part and a fixing part which are connected with each other, the sealing part is annular, and the fixing part is located on the radial inner side of the sealing part and located in the axial middle of the sealing part. Wherein the fixing part is connected with the piston, the surface, away from the fixing part in the radial direction, of the sealing part is matched with the inner wall of the air cylinder, and the surface, close to the fixing part in the radial direction, of the sealing part is matched with the piston so as to seal a fit clearance between the air cylinder and the piston. Therefore, when the piston and the air cylinder move relatively, the surface, away from the fixing part in the radial direction, of the sealing part of the leather cup slides relative to the inner wall of the air cylinder, the acting force of the air cylinder and the leather cup only enables the leather cup to be compressed in the radial direction of the sealing part and not to be bent repeatedly in the axial direction of the sealing part, and the situation that the leather cup is damaged due to fatigue is avoided; and the durability of the leather cup is improved.

Description

Technical Field

[0001] The present application relates to the field of air compression technology, and in particular to an air compressor and a vehicle. Background Art

[0002] An air compressor compresses air and delivers it to devices that require it. To achieve this, an air compressor typically has a cylinder and a piston. The piston moves within the cylinder. As the piston moves from top to bottom dead center, negative pressure forms within the cylinder, allowing gas to be drawn into the cylinder from the side where the piston connecting rod is located (a one-way vent valve is installed on the piston to allow gas to enter the cylinder but prevent it from leaking out in the opposite direction). As the piston moves from bottom to top dead center, the space within the piston is compressed, allowing gas to be pumped out through the cylinder head that matches the cylinder, completing the high-pressure gas output.

[0003] It can be seen that the piston is constantly reciprocating in the cylinder, and the piston needs to be sealed with the cylinder. Otherwise, the high-pressure gas may be discharged from the cylinder through the gap between the piston and the cylinder, and cannot be pumped out from the cylinder head. To achieve this, a leather cup is installed on the side of the piston. The leather cup is fixed to the piston and abuts against the cylinder wall, thus sealing the gap between the cylinder and the piston.

[0004] The leather cup reciprocates with the piston, and a traditional leather cup is usually a sheet-shaped ring. The radially inner side of such a leather cup is clamped by the piston, and the part not clamped by the piston is bent toward the axial direction of the leather cup, so that one axial side of the leather cup mates with the cylinder. This arrangement causes the leather cup to bend repeatedly along its axial direction. Specifically, when the piston moves from top dead center to bottom dead center, the axial side of the leather cup facing the piston rod mates with the cylinder. When the piston moves from bottom dead center to top dead center, the axial side of the leather cup facing away from the piston rod mates with the cylinder. Therefore, when the piston moves to top dead center or bottom dead center, the side of the leather cup that mates with the cylinder must be swapped, which causes the leather cup to bend repeatedly along its axial direction, leading to leather cup fatigue and subsequent cracking and damage. Therefore, the service life of a leather cup with such an arrangement is usually short. Utility Model Content

[0005] The embodiments of the present application provide an air compressor and a vehicle, which improve the durability of the leather cup to at least partially solve the above-mentioned technical problems.

[0006] In order to achieve the above-mentioned object, according to a first aspect of the present application, an air compressor is provided, comprising:

[0007] A cylinder and piston that cooperate with each other;

[0008] The leather cup comprises a fixing portion and a sealing portion connected to each other, wherein the sealing portion is annular, the fixing portion is located radially inward of the sealing portion and axially in the middle of the sealing portion, and the fixing portion is connected to the piston;

[0009] Wherein, the surface of the sealing portion radially away from the fixing portion is in interference fit with the inner wall of the cylinder, and the surface of the sealing portion radially close to the fixing portion is in fit with the piston to seal the fitting gap between the cylinder and the piston.

[0010] Optionally, the surface of the sealing portion radially away from the fixing portion is the first fitting surface; in the moving plane of the central axis of the piston, the first fitting surface is an arc.

[0011] Optionally, the first fitting surface is a spherical zone, and along the axial direction of the sealing portion, the first fitting surface is symmetrically arranged relative to the fixing portion.

[0012] Optionally, the surface of the sealing portion radially close to the fixing portion is in clearance fit with the piston.

[0013] Optionally, the surface of the sealing portion radially close to the fixing portion is the second fitting surface, and a third fitting surface matching with the second fitting surface is arranged on the piston; the first fitting surface, the second fitting surface and the third fitting surface are all spherical zones independently, and along the axial direction of the sealing portion, the first fitting surface, the second fitting surface and the third fitting surface are all symmetrically arranged relative to the fixing portion independently.

[0014] Optionally, in the moving plane of the central axis of the piston, the first fitting surface has two contact positions with the inner wall of the cylinder, and the connection line of the two contact positions is perpendicular to the axial direction of the cylinder.

[0015] Optionally, the diameter of the surface of the cylinder close to the fixing portion is φ, and the thickness of the sealing portion in the radial direction is h, and h satisfies the following constraint: h≥0.04*φ.

[0016] Optionally, the radial radius of the surface of the sealing portion radially away from the fixing portion is L1, and the interference amount x is L1 - 0.5*φ, and x satisfies the following constraint: x≥0.01φ.

[0017] Optionally, in the moving plane of the central axis of the piston, the opening angle of the sealing portion is θ1; the maximum included angle between the central axis of the piston and the central axis of the cylinder is θ2, and θ1 and θ2 satisfy the following constraint: θ1 / θ2≥1.15.

[0018] Optionally, θ1 and θ2 satisfy the following constraint:

[0019] 1.3≥θ1 / θ2≥1.2.

[0020] Optionally, a ring groove is provided on the piston, and the ring groove is coaxially arranged with the piston; at least a part of the fixing portion is arranged in the ring groove and is in interference fit with the ring groove.

[0021] According to a second aspect of the present application, a vehicle is further provided, including the above-mentioned air compressor.

[0022] In the air compressor of the embodiment of the present application, the radially outer surface of the annular sealing portion away from the fixing portion is in interference fit with the inner wall of the cylinder, so that no matter where the piston moves, the leather cup is always the radially outer surface of the sealing portion away from the fixing portion that is in interference fit with the cylinder, and there is no situation where the mating surface between the leather cup and the cylinder wall needs to alternate back and forth. In addition, the fixing portion is arranged on the radially inner side of the sealing portion and is located in the middle of the sealing portion in the axial direction. This is equivalent to that both sides of the sealing portion in the axial direction protrude from the fixing portion. The part of the sealing portion protruding from the fixing portion is not blocked by the fixing portion, and can directly face the piston. Also, since the radially inner surface of the sealing portion close to the fixing portion is in contact with the piston, under the extrusion of the cylinder, the radially inner surface of the sealing portion close to the fixing portion can abut against the piston. In this way, the sealing portion can seal the mating gap between the piston and the cylinder, and also enables the sealing portion to obtain the supporting force from the piston radially outward along the sealing portion. Therefore, during the movement of the piston, the cylinder can extrude the sealing portion from the radially outer side of the sealing portion, and the piston can extrude the sealing portion from the radially inner side of the sealing portion, so that the sealing portion adheres to the surface of the piston, and thus will not bend along the axial direction of the sealing portion, thereby avoiding fatigue damage of the leather cup and improving the durability of the leather cup.

[0023] Other features and advantages of the present application will be described in detail in the subsequent specific implementation part. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] In order to more completely understand the present application and its beneficial effects, the following description will be made in conjunction with the drawings, where the same reference numerals represent the same parts in the following description.

[0026] Figure 1 is a schematic structural diagram of a piston and a cylinder in an air compressor provided in an exemplary embodiment of the present disclosure;

[0027] Figure 2 is Figure 1 a schematic overall structural diagram of a leather cup in the shown air compressor;

[0028] Figure 3 is Figure 1 The first cross-sectional schematic view in the A-A direction in

[0029] Figure 4 is Figure 3 The enlarged schematic view of part B in

[0030] Figure 5 is Figure 1 The second cross-sectional schematic view in the A-A direction in

[0031] Figure 6 is Figure 5 The enlarged schematic view of part C in

[0032] Figure 7 is Figure 2 The cross-sectional structure schematic view of the embodiment in

[0033] Figure 8 is Figure 1 The structure schematic view of the piston and the leather cup matching in the embodiment in

[0034] Figure 9 is Figure 8 The explosion structure schematic view of the embodiment in

[0035] Figure 10 is Figure 8 The structure schematic view of the embodiment after removing the leather cup.

[0036] Explanation of the reference numerals in the drawings:

[0037] 100, leather cup; 110, sealing part; 111, first mating surface; 111a, first surface; 111b, second surface; 112, second mating surface; 120, fixing part;

[0038] 200, cylinder; 201, first axis;

[0039] 300, piston; 310, piston rod; 320, piston head; 330, screw; 340, check valve; 301, third mating surface; 302, second axis; 303, ring groove;

[0040] 401, first contact position; 402, second contact position; 403, third contact position; 404, fourth contact position. Detailed implementation manners

[0041] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present application.

[0042] According to the first aspect of the present application, with reference to Figure 1 , the present disclosure provides an air compressor, including a cylinder 200 and a piston 300. In combination with Figure 2 , the air compressor further includes a leather cup 100. The leather cup 100 includes a sealing portion 110 and a fixing portion 120 that are connected to each other. The sealing portion 110 is annular, and the fixing portion 120 is disposed inside the sealing portion 110 in the radial direction and is located in the middle of the sealing portion 110 in the axial direction. The fixing portion 120 is connected to the sealing portion 110, which may be that the sealing portion 110 and the fixing portion 120 are adhesively connected to each other, snap-fitted to each other, or integrally formed, so that the sealing portion 110 and the fixing portion 120 form a whole, that is, the leather cup 100. Thus, when the sealing portion 110 is connected to the piston 300, the leather cup 100 is integrally fixed to the piston 300. In some embodiments, the fixing portion 120 may be a fixing post protruding radially inward along the sealing portion 110, and a plurality of fixing portions 120 may be spaced apart along the circumferential direction of the sealing portion 110. The plurality of fixing portions 120 are inserted into holes provided on the piston 300 corresponding to the sealing portion 110 one by one, and are in interference fit or adhesively connected with the holes, so as to be fixed to the piston 300. Other embodiments of the fixing portion 120 may refer to the embodiments described below.

[0043] Referring to Figure 1 , the piston 300 cooperates with the cylinder 200, and one end of the piston 300 enters the cylinder 200. One end of the piston 300 outside the cylinder 200 may be connected to a crank-link mechanism or some other eccentric motion mechanism, so as to be driven, and then reciprocate inside the cylinder 200. In combination with Figure 3 , Figure 3 shows the positional relationship between the piston 300 and the cylinder 200 when the piston 300 is at the top dead center or the bottom dead center. It can be seen that the leather cup 100 is disposed on the piston 300 and is located between the piston 300 and the cylinder 200. The inner side in the radial direction of the leather cup 100 faces the piston 300 and cooperates with the piston 300, and the outer side in the radial direction cooperates with the inner wall of the cylinder 200, thereby sealing the gap between the piston 300 and the cylinder 200 and preventing gas from flowing out of the cylinder 200 through this gap. The inner side in the radial direction of the leather cup 100 and the piston 300 may be in clearance fit, transition fit, or interference fit. No matter what kind of fit it is, the sealing portion 110 can be pushed by the cylinder, so that the inner side in the radial direction of the sealing portion 110 abuts against the piston 300. In this way, the inner and outer sides in the radial direction of the leather cup 100 can respectively abut against the cylinder 200 and the piston 300, sealing the mating gap between the cylinder 200 and the piston 300. Further in combination with Figure 4, it can be seen that the outer side surface in the radial direction of the sealing portion 110 of the leather cup 100 (or, the surface of the sealing portion 110 radially away from the fixing portion) cooperates with the inner wall of the cylinder 200. Since the fixing portion 120 is provided in the middle of the sealing portion 110, both sides of the sealing portion 110 along the axial direction of the leather cup 100 protrude from the fixing portion 120. Therefore, the two sides of the sealing portion 110 protruding from the fixing portion 120 can directly contact the piston 300 without being blocked by the fixing portion 120 and obtain the support of the piston 300. On the other hand, in order to maintain the airtightness, the outer side surface in the radial direction of the sealing portion 110 (or, the surface of the sealing portion 110 radially away from the fixing portion) is in interference fit with the inner wall of the cylinder 200, that is to say, the leather cup 100 and the cylinder 200 are in interference fit. In this way, the cylinder 200 will squeeze the sealing portion 110, and the part of the sealing portion 110 protruding from the fixing portion 120 will be squeezed by the piston 300. The cylinder 200 and the piston 300 simultaneously squeeze the inner and outer sides in the radial direction of the sealing portion 110, so that the sealing portion 110 can be tightly attached to the surface of the piston 300 during the movement of the piston 300 and will not be bent along the axial direction of the sealing portion (only undergo compressive deformation under the extrusion of the piston 300 and the cylinder 200). In this way, the leather cup 100 will not be fatigued due to bending, avoiding damage of the leather cup 100 due to fatigue and improving the durability of the leather cup 100.

[0044] In some embodiments, referring to Figure 7 , the outer side surface in the radial direction of the sealing portion 110 (or, the surface of the sealing portion 110 radially away from the fixing portion) is the first mating surface 111, Figure 7 The cross-section of the leather cup 100 shown is the moving plane of the central axis of the piston 300. It can be seen that the first mating surface 111 is an arc on this cross-section. Figure 1 The cross-section in the A-A direction shown is the moving plane of the central axis of the piston 300. Combining Figure 3 and Figure 5 (Both of these two figures are cross-sectional schematic diagrams on the cross-section in the A-A direction), it can be seen that the central axis of the piston 300, i.e., the second axis 302, will move during the movement of the piston 300. In Figure 3 , the second axis 302 coincides with the central axis of the cylinder, i.e., the first axis 201. At this time, the piston 300 moves to the top dead center or the bottom dead center; in Figure 5 , the piston 300 moves to a position between the top dead center and the bottom dead center. Therefore, the first axis 201 and the second axis 302 form an angle. However, as the piston 300 moves, the second axis 302 has been moving in a plane. Therefore, the moving plane of the second axis 302 can determine a cross-section. Further referring to Figure 4 and Figure 6 it can be seen that on this cross-section, the first mating surface 111 is an arc. Referring to Figure 7, this feature can also be understood as the first mating surface 111 including a first surface 111a and a second surface 111b, where the first surface 111a and the second surface 111b are joined; the first surface 111a extends axially from the second surface 111b towards the sealing portion 110 and is inclined inwards radially towards the sealing portion 110, which is actually equivalent to the first surface 111a extending along one side of the axial direction of the sealing portion 110 while being inclined inwards radially towards the sealing portion 110; at the same time, the second surface 111b extends axially from the first surface 111a towards the sealing portion 110 and is inclined inwards radially towards the sealing portion 110, which is equivalent to the second surface 111b extending along the other side of the axial direction of the sealing portion 110 while being inclined inwards radially towards the sealing portion 110. This makes the first mating surface 111 present as an arc on the cross-section as shown in Figure 7 .

[0045] Of course, in some other embodiments of the present application, on the moving plane of the central axis of the piston, the first mating surface can present as a straight line, so that the first mating surface is actually a cylindrical surface, and in this way, the forming of the sealing portion is simple and the manufacturing cost is low. Figure 3 Combined with Figure 5 , it can also be seen that the first axis 201 and the second axis 302 are in the same plane, that is, in the moving plane of the second axis 302. Figure 3 And Figure 5 The cross-sections of are actually the same plane, only the mating positions of the piston 300 and the cylinder 200 are different. In the state shown in Figure 3 , the piston 300 is at the top dead center or the bottom dead center, and at this time, the first axis 201 and the second axis 302 coincide; in the state shown in Figure 5 , the piston 300 is in the state between the top dead center and the bottom dead center and is at the position with the largest yaw degree, that is, at the position where the included angle between the first axis 201 and the second axis 302 is the largest. From this, it can be seen that during the movement of the piston 300, the relative angle with the cylinder 20 is changed.

[0046] In the above embodiment where the first mating surface 111 presents as an arc on the moving plane of the central axis of the piston 300, the change in the relative angle between the central axis of the piston 300 and the central axis of the cylinder 200 will cause different positions of the sealing portion 110 of the leather cup 100 to abut against the cylinder 200. On the cross-section shown in Figure 4 , the first contact position 401 and the second contact position 402 on the first mating surface 111 cooperate with the inner wall of the cylinder 200, while in Figure 6On the cross-section shown, the third contact position 403 and the fourth contact position 404 on the first mating surface 111 cooperate with the inner wall of the cylinder 200. The interference amount between the leather cup 100 and the inner wall of the cylinder 200 also changes with the swing of the piston 300. Specifically, on the plane of the central axis movement of the piston 300, the interference amount between the leather cup 100 and the cylinder 200 is half of the distance between the contact positions on both sides in the radial direction of the leather cup 100 (the distance when the sealing portion 110 is in the natural state and not compressed), minus the radius of the inner wall of the cylinder 200. The interference amount determines the pressure between the leather cup 100 and the inner wall of the cylinder 200, and thus determines the sealing strength of the leather cup 100. However, the interference amount also determines the deformation degree of the leather cup 100. Therefore, the interference amount needs to be set within a suitable range. On the one hand, the interference amount should be large enough so that the pressure between the cylinder 200 and the leather cup 100 is large enough to provide sufficient sealing effect. On the other hand, the interference amount should not be too large to avoid excessive deformation of the sealing portion 110 resulting in damage. The first mating surface 111 presents an arc on the plane of the central axis movement of the piston 300, which actually adjusts the distance between the two opposite contact positions on the first mating surface 111. For example, in combination with reference Figure 4 and Figure 6 , the distance between the first contact position 401 and the second contact position 402 is actually the same as the distance between the third contact position 403 and the fourth contact position 404. Because in the embodiments shown in these two figures, the first mating surface 111 is a spherical zone (i.e., the part of the spherical surface intercepted by two parallel planes and between the two planes is the spherical zone), and the center of the spherical surface of the first mating surface 111 coincides with the center of the ring of the sealing portion 110 (or considered as the center of the sealing portion 110). The center of the ring refers to the center of the ring formed by the sealing portion 110. When the leather cup 100 cooperates with the piston 300 and the piston 300 cooperates with the cylinder 200, the center of the ring also often lies at the intersection of the first axis 201 and the second axis 302, that is, the intersection of the first axis 201 and the second axis 302 as shown in 6. Also for this reason, when the first mating surface 111 is a spherical zone and the center of the sphere is at the center of the ring of the sealing portion 110, no matter what position the piston 300 moves to, on the plane of the central axis movement of the piston 300, the distance between the two contact positions where the sealing portion 110 contacts the inner wall of the cylinder 200 is always the same. In this way, the interference amount remains consistent throughout the entire movement process of the piston 300. Since the interference amount remains consistent, the interference amount can be set larger without worrying about excessive local interference amount causing damage to the leather cup 100, thereby improving the sealing performance of the leather cup 100.

[0047] However, this solution is not limited to this, that is, the first mating surface may not be a spherical zone. For example, it can be made such that the two ends of the first mating surface in the axial direction of the sealing portion 110 are more inclined radially inward towards the sealing portion than the spherical zone surface. Or rather, when the included angle between the piston central axis and the cylinder central axis is the largest, the interference amount is reduced a little. In this way, while ensuring that the leather cup has sufficient sealing performance, the service life of the leather cup 100 can be further improved. Specifically, when the piston swings to the maximum extent, the piston is still at a certain distance from the top dead center position. And usually, when the piston is at the top dead center position, the space inside the cylinder is compressed to the minimum, so the air pressure inside the cylinder is the largest and the required sealing performance is the strongest. However, when the piston is far from the top dead center position, such strong sealing performance may not be needed. That is, when the degree of piston swing is the largest, the sealing performance of the leather cup can be appropriately reduced, the interference amount is decreased, and thus the deformation degree of the leather cup is reduced, avoiding the leather cup aging and losing elasticity under large deformation, thereby improving the service life of the leather cup. Generally speaking, the setting of the first surface and the second surface can change the interference amount between the leather cup and the cylinder during the entire movement process of the piston, so as to improve the sealing performance or increase the service life of the leather cup.

[0048] In some embodiments, referring to Figure 7 , the outer side surface in the radial direction of the sealing portion 110 (or rather, the surface of the sealing portion 110 radially away from the fixing portion) is the first mating surface 111. The first mating surface 111 is a spherical zone, and the first mating surface 111 is symmetrically arranged relative to the fixing portion 120 along the axial direction of the sealing portion 110. This actually also means that the center of the sphere of the first mating surface 111 coincides with the center of the ring of the sealing portion 110. Referring to the above text, the center of the ring is the center of the circle of the sealing portion 110. When the leather cup 100 is installed on the piston 300 and the piston 300 cooperates with the cylinder 200, this center of the ring is also often the intersection point of the cylinder 200 central axis and the piston 300 central axis, that is Figure 6 the intersection point of the first axis 201 and the second axis 302 shown in Figure 3 . The inner diameter of the cylinder 200 is φ, referring to Figure 7 . The spherical radius of the first mating surface 111 is L1. Therefore, the interference amount x = L1 - 0.5 * φ.

[0049] In some embodiments, referring to Figure 4, the inner side surface in the radial direction of the sealing portion 110 (or the surface of the sealing portion 110 close to the fixing portion in the radial direction) is in clearance fit with the piston 300. In this way, when the leather cup 100 is mounted on the piston 300, the piston 300 does not have a thrust against the sealing portion 110, and the sealing portion 110 will not deform, that is, there will be no prestress. Since the leather cup 100 may be mounted on the piston 300 and stored together with the piston 300 without being mated with the cylinder 200, such a setting allows the sealing portion 110 to be in a natural state when the leather cup 100 is stored, and will not lose its elasticity due to deformation, thereby improving the storage life of the leather cup 100. Refer to Figure 7 , for the embodiment in which the first mating surface 111 is provided with a first surface 111a and a second surface 111b, or the first mating surface 111 is a spherical zone, after the sealing portion 110 is mated with the cylinder 200, the portion that does not abut against the cylinder 200 can remain in a natural state and will not lose its elasticity due to maintaining deformation. Therefore, the service life of the leather cup 100 can be improved. In particular, for all the dimension measurements of the leather cup 100 in the present application (such as Figure 7 the outer diameter L1, inner diameter L2, the opening angle θ1 of the first mating surface 111 with respect to the center of the ring, and the radial thickness h of the sealing portion 110 shown in the leather cup 100), they can be carried out when the leather cup 100 is in two states. The first state is to measure the dimensions of the leather cup 100 when the leather cup 100 is not assembled and in a natural state. The second state is to measure the dimensions of the leather cup 100 when the leather cup 100 is assembled on the piston 300 but not mated with the cylinder 200. The dimensions of the leather cup 100 measured in any of the above states conform to the range defined in the present application, that is, within the protection scope of the present application. In addition, the clearance fit in the present application includes the situation where they are in contact with each other but do not generate mutual acting forces, that is, the case where the fit clearance is 0. Of course, in other embodiments, the sealing portion 110 can be in interference fit with the piston 300 so that the sealing portion 110 can closely adhere to the surface of the piston 300, improving the stability of the leather cup 100 during movement.

[0050] In some embodiments, refer to Figure 7 and Figure 9, the radially outer side surface of the sealing portion 110 (or, the surface of the sealing portion 110 radially away from the fixing portion) is the first mating surface 111, and the radially inner side surface of the sealing portion 110 (or the surface of the sealing portion 110 radially close to the fixing portion) is the second mating surface 112. A third mating surface 301 is provided on the piston 300 to cooperate with the second mating surface 112. The first mating surface 111, the second mating surface 112, and the third mating surface 301 are each independently a spherical zone. Along the axial direction of the sealing portion 110, the first mating surface 111, the second mating surface 112, and the third mating surface 301 are each independently symmetrically arranged relative to the fixing portion 120. This can also be understood as the centers of the first mating surface 111, the second mating surface 112, and the third mating surface 301 coinciding with the center of the ring of the sealing portion 110. Referring to the above text, when the leather cup 100 is assembled onto the piston 300, referring to Figure 6 , the center of the ring of the sealing portion 110 often lies at the intersection of the first axis 201 and the second axis 302 (although during the entire movement of the piston 300, the position of this intersection changes relative to the cylinder 200, but the center of the ring is always at this intersection), and the leather cup 100 and the piston 300 also often swing around this point. This point is also on the central axis of the cylinder 200. Therefore, when the third mating surface 301 moves with the piston 300, in Figure 6 the shown cross-section, the distance from the surface of the third mating surface 301 to the inner wall of the cylinder 200 remains unchanged. This distance is actually slightly less than the distance between the first mating surface 111 and the second mating surface 112, that is, the leather cup 100 will deform under the extrusion of the inner wall of the cylinder 200 and the third mating surface 301, but the distance between the first mating surface 111 and the second mating surface 112 also remains unchanged. Therefore, this can ensure that when the piston 300 swings to any angle, the compression amount of the sealing portion 110 in its radial direction (when the sealing portion 110 is in the natural state, the distance between the first mating surface 111 and the second mating surface 112 minus the distance between the third mating surface 301 and the inner wall of the cylinder 200 is the compression amount of the sealing portion 110) remains unchanged. This makes the deformation amount of the sealing portion 110 always unchanged during the movement of the piston 300, avoiding the leather cup 100 being damaged due to excessive deformation amount of the sealing portion 110 at some positions during the movement of the piston 300. Under the above limitations, the deformation amount of the sealing portion 110 can be increased as much as possible without being damaged, providing better sealing performance. In addition, these embodiments also ensure that the interference amount x between the leather cup 100 and the cylinder 200 can remain unchanged. Refer to Figure 8 and Figure 9 , because in Figure 8 and Figure 9 the shown embodiments, the piston 300 has a piston rod 310 and a piston head 320. In combination with reference to Figure 4, the fixing part 120 is actually clamped by the piston rod 310 and the piston head 320. Therefore, the second mating surface 112 actually abuts against the piston rod 310 and the piston head 320 respectively on both sides of the fixing part 120 in the axial direction. Therefore, in Figure 9 it can be seen that the third mating surface 301 actually has two surfaces, which are respectively on the piston head 320 and the piston rod 310. However, in other embodiments, the piston head 320 may not be provided, and only a ring groove may be formed on the piston rod 310 for fixing the fixing part 120. In this way, the third mating surface 301 is only on the piston rod 310.

[0051] In some embodiments, referring to Figure 4 and Figure 6 , in the plane of the central axis of the piston 300, the first mating surface 111 has two contact positions with the inner wall of the cylinder 200, that is, Figure 4 the first contact position 401 and the second contact position 402 in Figure 6 or the third contact position 403 and the fourth contact position 404 in Figure 6 . As the piston 300 moves, the positions of the two contact positions will continuously change, but the line connecting the two contact positions is always perpendicular to the axis of the cylinder 200. The above contact positions should be understood as the contact positions between the cylinder 200 and the leather cup 100 when they are in cooperation but do not generate mutual acting forces (that is, when the interference fit is made but the fit distance is 0). Although the leather cup 100 and the inner wall of the cylinder 200 are in an interference fit state during use, it can be imagined that referring to Figure 6 , without changing the positions of the first axis 201 and the second axis 302, slightly expand the inner diameter of the cylinder 200 so that the cylinder 200 and the leather cup 100 are in the above state, and then determine the contact positions. Or the interference fit state between the leather cup 100 and the cylinder 200 can be maintained. In this way, the sealing part 110 and the cylinder 200 actually form a contact surface, and this contact surface presents a line in the cross-section shown in Figure 6On the shown cross-section, the forces exerted by the cylinder 200 on both sides of the leather cup 100 (the third contact position 403 and the fourth contact position 404) are collinear, so that no couple will be formed and the piston 300 will not have a tendency to rotate. The piston 300 cannot rotate freely during movement, and the rotation angle of the piston 300 is restricted by the driving mechanism of the piston 300 (the crank connecting rod mechanism or some eccentric motion mechanisms). Therefore, if the piston 300 has a tendency to rotate under the action of the cylinder 200, this tendency will be offset by the driving mechanism of the piston 300, thereby increasing the movement resistance of the piston 300. It can be seen that this embodiment can reduce the movement resistance of the piston 300 and increase the efficiency of the air compressor.

[0052] In some embodiments, referring to Figure 3 , the inner side surface of the cylinder 200 (or the surface of the cylinder 200 radially close to the fixed part) has a diameter of φ. With reference to Figure 7 , the radial thickness of the sealing part 110 is h. When both the first mating surface 111 and the second mating surface 112 are spherical zones, h = L1 - L2, that is, the spherical radius of the first mating surface 111 minus the spherical radius of the second mating surface 112. In other embodiments, the first mating surface 111 and the second mating surface 112 may not be spherical zones. Therefore, h can be just the distance between the first mating surface 111 and the second mating surface 112 in the radial direction along the sealing part 110. h satisfies the following constraint: h≥0.04*φ. It can be seen that in this embodiment, the thickness of the sealing part 110 has a certain relationship with the inner diameter of the cylinder 200, or it can be said that the minimum thickness of the sealing part 110 is 0.04 times the inner diameter of the cylinder 200. This is because generally, the larger the cylinder 200, the greater the air output of the air compressor, and the better the sealing performance required. In order for the sealing part 110 to press against the inner wall of the cylinder 200 to provide sufficient sealing performance, the required deformation amount is also larger. This deformation amount is in the radial direction of the sealing part 110. Therefore, the larger the radial thickness of the sealing part 110, the greater the deformation amount it can withstand. Therefore, making the minimum value of h increase with the increase of φ can meet the sealing requirements of the air compressor while avoiding damage to the leather cup 100 due to excessive new variable and improving the service life of the leather cup 100. Of course, h can be greater than the minimum value. For example, h can be 0.041*φ, 0.042*φ, 0.043*φ, 0.045*φ, 0.048*φ, 0.050*φ, 0.051*φ, 0.054*φ, 0.058*φ, 0.060*φ, etc., so as to further increase the thickness of the sealing part 110 and improve the service life of the leather cup 100.

[0053] In some embodiments, referring to Figure 7 , the radial outer side surface of the sealing part 110 (or the surface of the sealing part 110 radially away from the fixed part) has a radial radius of L1. Figure 7Since the first mating surface 111 is a spherical zone, L1 is the spherical radius of the first mating surface 111. In other embodiments, the first mating surface 111 may not be spherical, for example, it may be a cylindrical surface, then L1 can be the cylindrical radius. When the first mating surface 111 is irregular, L1 can be the average distance between the first mating surface 111 and the center of the ring. The interference amount x is L1 - 0.5*φ, and x satisfies the following constraint: x≥0.01φ. It can be seen that the minimum value of x is proportional to the inner diameter of the cylinder 200, that is, the larger the inner diameter of the cylinder 200, the larger the minimum value of the interference amount. This is also because the larger the cylinder 200, the better the airtightness required. At this time, by increasing the interference amount x of the leather cup 100 and the cylinder 200, the airtightness of the leather cup 100 can be improved to meet the airtightness required by the air compressor. Of course, x can be larger than its minimum value, for example, it can be 0.011*φ, 0.012*φ, 0.013*φ, 0.015*φ, 0.017*φ, 0.019*φ, 0.020*φ, 0.023*φ, 0.025*φ, 0.027*φ, etc., so as to further increase the interference amount and improve the airtightness.

[0054] In some embodiments, referring to Figure 6 and Figure 7 , in the plane of the central axis of the piston 300, the opening angle of the sealing portion 110 is θ1, that is, the opening angle of the radially outer side of the sealing portion 110 (or, the surface of the sealing portion 110 radially away from the fixing portion) with respect to the center of the ring of the sealing portion 110 is θ1. For Figure 7 the embodiment, since the first mating surface 111 is a spherical zone, θ1 is the angle subtended by the arc presented by the first mating surface 111 at the center of the sphere of the first mating surface 111 in the cross-section shown in Figure 7 (note that the cross-section shown in Figure 7 and the cross-section shown in Figure 6 are actually the same cross-section, so Figure 7 the vertex of θ1 shown in Figure 6 is the center of the sphere of the first mating surface 111, the center of the ring of the sealing portion 110 or Figure 6 the intersection of the first axis 201 and the second axis 302 in Figure 7 ). When the first mating surface 111 is other curved surfaces, θ1 can be obtained by the following method: in the plane of the central axis of the piston 300 (that is, in the cross-section shown in Figure 7 ), find the end points at both ends of the first mating surface 111 in the axial direction of the sealing portion 110, and connect the two end points to the center of the ring of the sealing portion 110 respectively. The angle formed by the line segments connecting the two end points to the center of the ring is θ1. Refer to Figure 6, the maximum included angle between the central axis of the piston 300 and the central axis of the cylinder 200 is θ2, and θ1 and θ2 satisfy the following constraint: θ1 / θ2 ≥ 1.15. This is actually equivalent to the minimum value of θ1 being greater than or equal to 1.15 times θ2. Such a setting can ensure that when the piston 300 swings to the maximum extent, the contact positions of the sealing portion 110 with the inner wall of the cylinder 200 (i.e., Figure 6 the third contact position 403 and the fourth contact position 404 shown) are not at the axial edge of the sealing portion 110, ensuring that the contact area between the sealing portion 110 and the inner wall of the cylinder 200 is large enough to ensure airtightness. Of course, θ1 can be greater than its minimum value, for example, it can be 1.16*θ2, 1.18*θ2, 1.2*θ2, 1.21*θ2, 1.22*θ2, 1.23*θ2, 1.24*θ2, 1.25*θ2, 1.26*θ2, 1.27*θ2, 1.28*θ2, 1.29*θ2, 1.30*θ2 and other values, so as to further ensure airtightness.

[0055] Furthermore, θ1 / θ2 ≥ 1.2. This is actually equivalent to the minimum value of θ1 being greater than or equal to 1.2 times θ2. Such a setting can ensure that when the piston 300 swings to the maximum extent, the contact positions of the sealing portion 110 with the inner wall of the cylinder 200 (i.e., Figure 6 the third contact position 403 and the fourth contact position 404 shown) are not at the axial edge of the sealing portion 110, ensuring that the contact area between the sealing portion 110 and the inner wall of the cylinder 200 is large enough to ensure airtightness. Of course, θ1 can be greater than its minimum value, for example, it can be 1.21*θ2, 1.22*θ2, 1.23*θ2, 1.24*θ2, 1.25*θ2, 1.26*θ2, 1.27*θ2, 1.28*θ2, 1.29*θ2, 1.30*θ2 and other values, so as to further ensure airtightness.

[0056] Furthermore, 1.3 ≥ θ1 / θ2. For example, it can be 1.21*θ2, 1.22*θ2, 1.23*θ2, 1.24*θ2, 1.25*θ2, 1.26*θ2, 1.27*θ2, 1.28*θ2, 1.29*θ2, 1.30*θ2 and other values. This can avoid the excessive area of the outer side surface in the radial direction of the sealing portion 110, thereby avoiding the excessive dimension of the sealing portion 110 of the leather cup 100 along the axial direction of the leather cup 100 and avoiding the waste of the material for manufacturing the leather cup 100.

[0057] In some examples, θ1 and θ2 satisfy the following constraint: 1.3 ≥ θ1 / θ2 ≥ 1.2.

[0058] In some embodiments, referring to Figure 4, a ring groove 303 is provided on the piston 300, and the ring groove 303 is coaxially arranged with the piston 300. The fixing part 120 is at least partially arranged in the ring groove 303 and is in interference fit with the ring groove 303. In this way, the fixing part 120 can be clamped by the ring groove 303 to fix the leather cup 100 to the piston 300. At the same time, the fixing part 120 can also be in the shape of a ring sheet, that is, as Figure 2 shown in the shape. Since the fixing part 120 is in interference fit with the ring groove 303, it can also block the gap between the leather cup 100 and the piston 300, preventing the gas in the cylinder 200 from leaking out through the fitting gap between the leather cup 100 and the piston 300, and improving the sealing performance of the leather cup 100. Refer to Figure 9 , Figure 4 and Figure 10 . In the embodiment shown in this drawing, the ring groove 303 is actually formed by partially arranging the piston head and the piston rod 310 at intervals. At this time, the part where the piston head 320 abuts against the piston rod 310 can be welded to the piston rod 310, and the part spaced from the piston rod 310 and the piston rod 310 together form the ring groove 303. Refer to Figure 8 . The piston 300 may further include a screw 330 and a check valve 340. The screw 330 is in threaded fit with the threaded hole on the piston rod 310. The check valve 340 is actually a valve plate. The screw 330 passes through the check valve 340 and limits the check valve 340 between the screw head of the screw 330 and the piston head 320. The piston head 320 and the screw head of the screw 330 can be spaced apart to provide the check valve 340 with freedom of movement in the axial direction of the screw 330 to ensure smooth intake. In this embodiment, the intake of the cylinder 200 is completed by the piston 300. The piston rod 310 and the piston head 320 are both provided with interconnected intake holes. The outlet side of the intake hole can be covered by the check valve 3,40. In this way, when sealing is required, the gas in the cylinder 200 pushes the check valve 340 against the piston head 320 to seal the intake hole and prevent the intake hole from exhausting gas. When the intake hole intakes gas, the air flow can push open the check valve 340 to complete the intake.

[0059] According to the second aspect of the present disclosure, a vehicle is provided. The vehicle includes the above-mentioned air compressor, and the vehicle has all the beneficial effects of the above-mentioned air compressor, which will not be elaborated herein.

[0060] The vehicle may be a fuel vehicle, a plug-in hybrid vehicle or a new energy vehicle, etc., and the present disclosure does not make specific limitations in this regard. The air compressor can be used as the air source of the vehicle to inflate the tires of the vehicle. Or when the vehicle is equipped with an air suspension, the air compressor can inflate the airbag of the air suspension.

[0061] In the description of the present application, the terms "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "a plurality of" means two or more, unless otherwise specifically defined.

[0062] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0063] The embodiments, implementation manners and related technical features of the present application can be combined and replaced with each other without conflict.

[0064] The above are only the preferred embodiments of the present application and do not impose any form of limitation on the present application. However, any modification, equivalent change and modification made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application still fall within the scope of the technical solution of the present application.

Claims

1. An air compressor, characterized in that, Comprising: A cylinder and a piston that cooperate with each other; A leather cup, including a fixed part and a sealing part connected to each other. The sealing part is annular, the fixed part is located radially inside the sealing part, and in the middle of the sealing part axially. The fixed part is connected to the piston; Wherein, the surface of the sealing part radially away from the fixed part is in interference fit with the inner wall of the cylinder, and the surface of the sealing part radially close to the fixed part is in fit with the piston to seal the fitting gap between the cylinder and the piston.

2. The air compressor according to claim 1, wherein The surface of the sealing part radially away from the fixed part is the first fitting surface; in the moving plane of the central axis of the piston, the first fitting surface is an arc.

3. The air compressor according to claim 2, wherein The first fitting surface is a spherical zone, and along the axial direction of the sealing part, the first fitting surface is symmetrically arranged relative to the fixed part.

4. The air compressor according to any one of claims 1-3, characterized in that, The surface of the sealing part radially close to the fixed part is in clearance fit with the piston.

5. The air compressor according to claim 2, wherein The surface of the sealing part radially close to the fixed part is the second fitting surface, and a third fitting surface that cooperates with the second fitting surface is arranged on the piston; the first fitting surface, the second fitting surface, and the third fitting surface are all independently spherical zones, and along the axial direction of the sealing part, the first fitting surface, the second fitting surface, and the third fitting surface are all independently symmetrically arranged relative to the fixed part.

6. The air compressor according to claim 2, wherein In the moving plane of the central axis of the piston, there are two contact positions between the first fitting surface and the inner wall of the cylinder, and the connection line of the two contact positions is perpendicular to the axial direction of the cylinder.

7. The air compressor according to claim 2, wherein The diameter of the surface of the cylinder close to the fixed part is φ, and the thickness of the sealing part in the radial direction is h, and h satisfies the following formula constraint: h≥0.04*φ.

8. The air compressor according to claim 7, characterized in that The radial radius of the surface of the sealing part radially away from the fixed part is L1, and the interference amount x is L1 - 0.5*φ, and x satisfies the following formula constraint: x≥0.

9. The air compressor according to claim 2, wherein ​ 10. The air compressor according to claim 9, wherein, ​ 11. The air compressor according to claim 2, characterized in that, ​ 12. A vehicle, characterized in that, ​

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