Anti-separation piston type vacuum pump

Abstract

The utility model relates to the field of electric vacuum pumps, in particular to an anti-separation piston type vacuum pump. In the axial direction of a piston head, the piston head is composed of an upper half part and a lower half part, the part, close to a cylinder cover, of the piston head is the upper half part, the part, away from the cylinder cover, of the piston head is the lower half part, and the upper half part and the lower half part are distributed on the two sides of the center of the piston head structure. A first annular groove is formed in the outer surface of the circumference of the upper half portion of the piston head, a first protruding part is arranged on the inner ring of the wear-resisting ring, and the first protruding part is inserted into the first annular groove in a non-disengagement mode in the radial direction of the piston head. Compared with the prior art, the deformation fulcrum of the wear-resisting ring moves upwards, so that the length of the power arm of the deformation of the wear-resisting ring is shortened, the warping angle of the wear-resisting ring is reduced, and even the wear-resisting ring does not warp.

Description

TECHNICAL FIELD

[0001] The utility model relates to electric vacuum pump field, in particular to a kind of anti-disengagement piston type vacuum pump. BACKGROUND

[0002] As Figure 1 As shown in prior art, wear ring is arranged outside piston head, the outer ring of wear ring and the hole inner wall of cylinder hole slide contact, the inner ring of wear ring and the circumferential outer surface of piston head contact each other, wear ring is arranged between piston head and cylinder hole, to reduce or avoid the abrasion generated by relative motion of piston head and cylinder hole;When connecting rod piston assembly is relatively cylinder hole and does up and down reciprocating motion due to the moment transmission of crankshaft, piston head will first form upward or downward motion trend force relative to the inner ring of wear ring, this trend force further drives wear ring to form same direction motion trend force by friction force, further by the relative friction of outer ring of wear ring and cylinder hole forms linear motion;At this time, the first force generated by the hole inner wall of cylinder hole to the outer ring of wear ring and the second force generated by the circumferential outer surface of piston head to the inner ring of wear ring are opposite, which will make wear ring swing with the center point of piston head contact surface as fulcrum, with the length of the distance between the center point and the top of piston head as power arm length, and further cause wear ring to warp.

[0003] Therefore, the technical problem existing in prior art is how to reduce the warping amplitude of wear ring between piston head and cylinder hole during the reciprocating motion of piston head in cylinder hole. UTILITY MODEL CONTENTS

[0004] The utility model is directed to the above-mentioned defects in the prior art and provides an anti-disengagement piston type vacuum pump.

[0005] To achieve the above utility model purposes, the utility model adopts the following technical scheme:

[0006] An anti-disengagement piston type vacuum pump includes a cylinder body and a cylinder cover buckled on the cylinder body, a cylinder hole is arranged in the cylinder body, and a piston connecting rod assembly is further included, a piston head of the piston connecting rod assembly is inserted into the cylinder hole and performs reciprocating motion;A wear ring is further included, an inner ring of the wear ring is sleeved on a circumferential outer surface of the piston head, and an outer ring of the wear ring slide contacts with a hole inner wall of the cylinder hole.

[0007] Along the axial direction of the piston head, the piston head is composed of an upper half and a lower half, a part of the piston head close to the cylinder cover is the upper half, and a part of the piston head away from the cylinder cover is the lower half, the upper half and the lower half are distributed on both sides of the structural center of the piston head, a circumferential outer surface of the upper half of the piston head is provided with a first annular groove, and an inner ring of the wear ring is provided with a first protruding part, along the radial direction of the piston head, the first protruding part is non-detachably inserted into the first annular groove.

[0008] Further, the first annular groove is formed by radially recessing the circumferential outer surface of the piston head towards the axis of the piston head; the cross section of the first annular groove is dovetail-shaped, and along the radial direction of the piston head, the width of the groove mouth is smaller than the width of the groove bottom;

[0009] The shape of the first protrusion matches the shape of the first annular groove.

[0010] Further, the groove bottom wall of the first annular groove is circular arc-shaped.

[0011] Further, the circumferential outer surface of the upper half or the circumferential outer surface of the lower half of the piston head is further provided with a second annular groove, the inner ring of the wear-resistant ring is provided with a second protrusion, and along the radial direction of the piston head, the second protrusion is inserted into the second annular groove without being detached.

[0012] Further, the number of the second annular grooves can be multiple, the number of the second protrusions is equal to the number of the second annular grooves, and along the radial direction of the piston head, any second protrusion is inserted into one of the second annular grooves without being detached.

[0013] Further, the outer surface of the piston head is further provided with a containing groove, the containing groove is provided with a sealing filling medium, along the radial direction of the piston head, there is a first gap between the sealing filling medium and the inner wall of the cylinder, and the first gap is filled by the end of the wear-resistant ring.

[0014] Further, the number of the containing grooves is two, and along the axial direction of the piston head, the first annular groove is located between the two containing grooves.

[0015] Further, the containing groove is an annular groove structure and is distributed around the axis of the piston head.

[0016] Further, it further comprises an open sealing ring, along the radial direction of the piston head, the open sealing ring is arranged between the circumferential outer surface of the piston head and the inner wall of the hole of the cylinder hole, and is in interference fit with the circumferential outer surface of the piston head and the inner wall of the hole of the cylinder hole respectively;

[0017] Along the axial direction of the piston head, the wear-resistant ring is located on one side of the open sealing ring.

[0018] Further, the circumferential outer surface of the piston head is provided with a clamping groove, and one part of the open sealing ring is clamped in the clamping groove.

[0019] Compared with the prior art, the advantages of the utility model lie in that:

[0020] In the utility model, the first protruding part of the inner ring of the wear -resisting ring is inserted into the first annular groove on the outer circumferential surface of the upper half of the piston head, when the piston head reciprocates in the cylinder hole, the wear -resisting ring is subjected to the two opposite forces of the circumferential inner wall of the cylinder hole and the circumferential outer surface of the piston head, and the wear -resisting ring warps with the first annular groove towards the groove inner wall of the cylinder cover as the fulcrum and the length of the distance between the groove inner wall and the top of the piston head as the power arm length, it can be seen that, compared with the prior art, the fulcrum of the deformation of the wear -resisting ring is moved up, the power arm length of the deformation of the wear -resisting ring is shortened, which reduces the angle of the warping of the wear -resisting ring, and even no warping is produced.

[0021] In the utility model, the first protruding part and the first annular groove between the wear -resisting ring and the piston head are connected, when the piston head moves, the pulling force of the piston head to the wear -resisting ring is increased through the connection of the first protruding part and the first annular groove, that is, the same direction movement ability of the wear -resisting ring relative to the piston head is increased.

[0022] In the utility model, a second annular groove and a second protruding part inserted into the second annular groove can be regarded as a set of connecting components, and multiple sets of connecting components can further strengthen the strength of the connection between the wear -resisting ring and the piston head.

[0023] In the utility model, the sealing filling medium is arranged on the one section of the wear -resisting ring at the end along the radial direction of the piston head, so that the one section of the wear -resisting ring at the end is tightly attached to the hole inner wall of the cylinder hole and slides, on the one hand, the air tightness between the cylinder hole and the wear -resisting ring and between the wear -resisting ring and the piston head is guaranteed, and the wear -resisting ring is prevented from being thinned or deformed due to abrasion after the piston head reciprocates multiple times, so that the air tightness between the cylinder hole and the wear -resisting ring and between the wear -resisting ring and the piston head is reduced, on the other hand, if the sealing filling medium is not arranged, the outer surface of the one section of the wear -resisting ring at the end is subjected to the friction of the circumferential inner wall of the cylinder hole, and the inner surface is not subjected to the friction due to being located at the slot opening of the containing groove of the piston head, so that the acting force and stress of the inner ring and the outer ring of the wear -resisting ring exist difference, and the one section of the wear -resisting ring at the end is warped, the sealing filling medium is used to tightly support the one section of the wear -resisting ring at the end in the utility model, so that the one section of the wear -resisting ring at the end is tightly attached to the hole inner wall of the cylinder hole, and the one section of the wear -resisting ring at the end is further prevented from being warped, that is, the deformation of the one section of the wear -resisting ring at the end is further prevented.

[0024] Five, the utility model discloses a set of open seal ring, can effectively carry out secondary sealing between piston head and cylinder hole, i.e. along the radial direction of piston head, sealing filling medium is pressed against the inner wall of cylinder hole of wear -resistant ring and is the first sealing structure, open seal ring is set between the circumferential outer surface of piston head and the inner wall of cylinder hole, and is respectively with the interference fit of circumferential outer surface of piston head and the inner wall of cylinder hole, is the second sealing structure, two sealing structures make the piston head of the utility model and the cylinder hole, and the sealing effect is better. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is the principle diagram of the warping of wear -resistant ring in the background art;

[0026] Figure 2 is the structure section schematic diagram of the anti -disengagement piston type vacuum pump of the utility model;

[0027] Figure 3 is Figure 2 the structure enlarged schematic drawing of region I in

[0028] Figure 4 is Figure 2 the structure enlarged schematic drawing of region II in

[0029] Figure 5 is the principle diagram of the warping of wear -resistant ring in the utility model.

[0030] Mark in the drawing: cylinder (1), cylinder hole (2), piston head (3), wear -resistant ring (4), first protruding portion (5), first annular groove (6), accommodating groove (7), sealing filling medium (8), open seal ring (9), clamping groove (10), cylinder cover (11), piston connecting rod assembly (12). DETAILED DESCRIPTION

[0031] The following detailed, non-limiting description of the utility model's technical solution, in conjunction with preferred embodiments and accompanying drawings, is provided. In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "length h," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0032] Example 1

[0033] The anti-detachment piston vacuum pump of this embodiment is preferably a piston vacuum pump, which has three cylinders and three piston connecting rod assemblies. Each cylinder is arranged to correspond to one of the piston connecting rod assemblies. The three piston connecting rod assemblies are also connected to a crankshaft assembly arranged in the housing. The crankshaft assembly is driven to rotate by a motor, thereby driving the three piston connecting rod assemblies to move up and down reciprocally, thus realizing the pumping function. This embodiment uses one set of cylinders and piston connecting rod assemblies as an example to illustrate the improvement of this embodiment over the prior art.

[0034] Reference Figures 2 to 4 This utility model proposes an anti-detachment piston vacuum pump, which includes a cylinder body 1 and a cylinder cover 11 fastened to the cylinder body 1. A cylinder bore 2 is provided in the cylinder body 1. It also includes a piston connecting rod assembly 12, the piston head 3 of the piston connecting rod assembly 12 is inserted into the cylinder bore 2 and performs reciprocating motion; it also includes a wear-resistant ring 4, the inner ring of the wear-resistant ring 4 is sleeved on the outer circumference of the piston head 3, and the outer ring of the wear-resistant ring 4 slides in contact with the inner wall of the cylinder bore 2.

[0035] Along the axial direction of the piston head 3, the piston head 3 is composed of an upper part and a lower part. The part of the piston head 3 close to the cylinder head 11 is the upper part, and the part of the piston head 3 away from the cylinder head 11 is the lower part. The upper and lower parts are distributed on both sides of the center of the piston head 3 structure. A first annular groove 6 is provided on the outer circumference of the upper part of the piston head 3. A first protrusion 5 is provided on the inner ring of the wear-resistant ring 4. Along the radial direction of the piston head 3, the first protrusion 5 is inseparably inserted into the first annular groove 6.

[0036] The cylinder body 1, also known as the piston cylinder, has a smooth circular inner wall; the piston connecting rod assembly 12 includes components such as the piston head 3, connecting rod, and bearings; this part is prior art and will not be described in detail here.

[0037] The wear-resistant ring 4 is an annular component made of wear-resistant material. The wear-resistant material can be any material known in the prior art, and there is no limitation on it. It has a circumferential outer surface and a circumferential inner surface. The inner ring of the wear-resistant ring 4 is fitted on the circumferential outer surface of the piston head 3. At the same time, the outer ring of the wear-resistant ring 4 is in sliding contact with the inner wall of the cylinder bore 2.

[0038] The first protrusion 5 of the wear-resistant ring 4 is the male head, and the first annular groove 6 of the piston head 3 is the female head. The first protrusion 5 is inserted into the first annular groove 6 in a way that makes it inseparable. Specifically, the first annular groove 6 is formed by radially recessing the outer circumference of the piston head 3 towards the axis of the piston head 3. The cross-section of the first annular groove 6 is dovetail-shaped. Along the radial direction of the piston head 3, the width of the groove opening of the first annular groove 6 is smaller than the width of the groove bottom. The shape of the first protrusion 5 matches the shape of the first annular groove 6. The following processing method can be adopted: when the wear-resistant material is arranged on the surface of the piston head 3, a portion of the liquid wear-resistant material is poured into the first annular groove 6 of the piston head 3, so that the wear-resistant material in each place is interconnected to form a whole. Then, it is allowed to solidify. The solidified wear-resistant material inside the first annular groove 6 is the first protrusion 5, and the solidified wear-resistant material outside the first annular groove 6 is the wear-resistant ring 4. Preferably, the bottom wall of the first annular groove 6 is arc-shaped, which facilitates the insertion of the machining tool and allows the liquid wear-resistant material to fill the entire space of the first annular groove 6.

[0039] As can be seen from the background art, the existing technical problem is how to reduce the warping amplitude of the wear ring located between the piston head and the cylinder bore during the reciprocating motion of the piston head in the cylinder bore.

[0040] like Figure 5 As shown, in this embodiment, a first annular groove 6 is provided on the outer circumference of the upper half of the piston head 3, and a first protrusion 5 is provided on the inner ring of the wear ring 4. Along the radial direction of the piston head 3, the first protrusion 5 is inextricably inserted into the first annular groove 6. When the piston head 3 reciprocates in the cylinder bore 2, the wear ring 4 is subjected to two opposing forces from the inner circumference of the cylinder bore and the outer circumference of the piston head 3. The wear ring 4 warps with the inner wall of the groove of the first annular groove 6 facing the cylinder head 11 as the fulcrum and the distance between the inner wall of the groove and the top of the piston head 3 as the power arm length. It can be seen that, compared with the prior art, the fulcrum of the wear ring 4 deformation is moved upward in this embodiment, which leads to a shortening of the power arm length of the wear ring 4 deformation. This will result in a reduction in the warping angle of the wear ring 4, or even no warping.

[0041] In addition, in this embodiment, the wear-resistant ring 4 and the piston head 3 are connected by the first protrusion 5 and the first annular groove 6, which are inseparable. When the piston head 3 moves, the pulling force of the piston head 3 on the wear-resistant ring 4 will increase through the connection between the first protrusion 5 and the first annular groove 6, which increases the ability of the wear-resistant ring 4 to move in the same direction relative to the piston head 3.

[0042] like Figure 2 As shown, further, a second annular groove is provided on the outer circumferential surface of either the upper or lower half of the piston head 3, and a second protrusion is provided on the inner ring of the wear-resistant ring 4. Along the radial direction of the piston head 3, the second protrusion is inextricably inserted into the second annular groove. Preferably, there can be multiple second annular grooves, and the number of second protrusions is equal to the number of second annular grooves. Along the radial direction of the piston head 3, any one of the second protrusions is inextricably inserted into one of the second annular grooves. The structure of the second protrusion is similar to the structure of the first protrusion 5, and the structure of the second annular groove is similar to the structure of the first annular groove 6.

[0043] In this embodiment, a second annular groove and a second protrusion inserted into the second annular groove can be regarded as a set of connecting parts. Multiple sets of connecting parts ensure that the connection between the wear-resistant ring 4 and the piston head 3 is further strengthened.

[0044] Furthermore, such as Figure 2 , Figure 3 As shown, the outer surface of the piston head 3 is also provided with a receiving groove 7, and a sealing filling medium 8 is disposed in the receiving groove 7. Along the radial direction of the piston head 3, there is a first gap between the sealing filling medium 8 and the inner wall of the cylinder 1. The first gap is extended into and filled by a section of the wear-resistant ring 4 located at the end. Preferably, the receiving groove 7 is an annular groove structure, distributed around the axis of the piston head 3. Preferably, there are two receiving grooves 7. Along the axial direction of the piston head 3, a first annular groove 6 is located between the two receiving grooves 7, and a sealing filling medium 8 is disposed in either receiving groove 7. Preferably, the two receiving grooves 7 are respectively disposed on the sides of the two sections at the two ends of the wear-resistant ring 4, that is, one receiving groove 7 is disposed on one side of a section at one end of the wear-resistant ring 4, and the other receiving groove 7 is disposed on one side of a section at the other end of the wear-resistant ring 4, thereby preventing the two sections at the two ends of the wear-resistant ring 4 from warping. Further, the material of the sealing filling medium 8 is selected from one of the prior art, such as rubber.

[0045] Along the radial direction of the piston head 3, the sealing filling medium 8 abuts against the end portion of the wear-resistant ring 4, so that the end portion of the wear-resistant ring 4 slides against the inner wall of the cylinder hole 2. In this way, on the one hand, the air tightness between the cylinder hole 2 and the wear-resistant ring 4 and between the wear-resistant ring 4 and the piston head 3 is ensured, so as to prevent the wear-resistant ring 4 from being thinned or deformed due to wear after multiple reciprocating movements of the piston head 3, and thus the air tightness between the cylinder hole 2 and the wear-resistant ring 4 and between the wear-resistant ring 4 and the piston head 3 is reduced. On the other hand, if the sealing filling medium 8 is not arranged, the outer surface of the end portion of the wear-resistant ring 4 is rubbed by the circumferential inner wall of the cylinder hole 2, while the inner surface of the end portion of the wear-resistant ring 4 is not rubbed because it is located at the notch of the accommodating groove 7 of the piston head 3. Thus, the force and stress acting on the inner and outer circles of the wear-resistant ring 4 are different, which will cause the end portion of the wear-resistant ring 4 to be warped. In the embodiment, the sealing filling medium 8 is arranged to abut against the end portion of the wear-resistant ring 4, so that the end portion of the wear-resistant ring 4 is tightly attached to the inner wall of the cylinder hole 2, thereby further preventing the end portion of the wear-resistant ring 4 from being warped, i.e., further preventing the end portion of the wear-resistant ring 4 from being deformed.

[0046] As shown in Figure 4 Further, the anti-disengagement piston vacuum pump of the embodiment further comprises an open sealing ring 9. Along the radial direction of the piston head 3, the open sealing ring 9 is arranged between the circumferential outer surface of the piston head 3 and the inner wall of the cylinder hole 2 and is in interference fit with the circumferential outer surface of the piston head 3 and the inner wall of the cylinder hole 2, respectively. Along the axial direction of the piston head 3, the wear-resistant ring 4 is located on one side of the open sealing ring 9. Preferably, the open sealing ring 9 is located at the bottom of the piston head 3.

[0047] In the embodiment, the arrangement of the open sealing ring 9 can effectively perform secondary sealing between the piston head 3 and the cylinder hole 2. That is, along the radial direction of the piston head 3, the abutment of the sealing filling medium 8 against the wear-resistant ring 4 to slide against the inner wall of the cylinder hole 2 is the first sealing structure, and the arrangement of the open sealing ring 9 between the circumferential outer surface of the piston head 3 and the inner wall of the cylinder hole 2 and in interference fit with the circumferential outer surface of the piston head 3 and the inner wall of the cylinder hole 2 is the second sealing structure. The two sealing structures make the sealing effect between the piston head 3 and the cylinder hole 2 of the embodiment better.

[0048] Further, the circumferential outer surface of the piston head 3 is provided with a clamping groove 10, and a part of the open sealing ring 9 is clamped in the clamping groove 10, so that the open sealing ring 9 is connected to the piston head 3.

[0049] The above-described embodiments only express several implementation manners of the utility model, the description is more specific and detailed, but can not therefore be understood as the limitation of the utility model patent range. It should be pointed out that for ordinary skilled person in the art, without departing from the utility model concept, several deformations and improvements can be made, which belong to the protection range of the utility model. Therefore, the protection range of the utility model patent should be subject to the appended claims.

Claims

1. A non-separation preventing piston vacuum pump characterized by, The application relates to an engine, which comprises a cylinder (1), a cylinder cover (11) buckled on the cylinder (1), a cylinder hole (2) arranged in the cylinder (1), a piston connecting rod assembly (12), a piston head (3) of the piston connecting rod assembly (12) inserted into the cylinder hole (2) and reciprocating, a wear-resistant ring (4), an inner ring of the wear-resistant ring (4) sleeved on the circumferential outer surface of the piston head (3), and an outer ring of the wear-resistant ring (4) in sliding contact with the hole inner wall of the cylinder hole (2). Along the axial direction of the piston head (3), the piston head (3) is composed of an upper half and a lower half, the part of the piston head (3) close to the cylinder cover (11) is the upper half, the part of the piston head (3) away from the cylinder cover (11) is the lower half, the upper half and the lower half are distributed on the two sides of the structural center of the piston head (3), the circumferential outer surface of the upper half of the piston head (3) is provided with a first annular groove (6), the inner ring of the wear-resistant ring (4) is provided with a first protruding part (5), and along the radial direction of the piston head (3), the first protruding part (5) is inserted into the first annular groove (6) in an inseparable mode.

2. The anti-separation piston vacuum pump according to claim 1, characterized in that The first annular groove (6) is formed by the radial recess of the circumferential outer surface of the piston head (3) towards the axial direction of the piston head (3); the cross section of the first annular groove (6) is dovetail-shaped, and along the radial direction of the piston head (3), the width of the groove mouth of the first annular groove (6) is smaller than the width of the groove bottom. The shape of the first protruding part (5) is matched with the shape of the first annular groove (6).

3. The anti-disengagement piston vacuum pump according to claim 2, characterized in that, The groove bottom wall of the first annular groove (6) is arc-shaped.

4. The anti-separation piston vacuum pump according to claim 3, characterized in that The circumferential outer surface of the upper half or the circumferential outer surface of the lower half of the piston head (3) is further provided with a second annular groove, the inner ring of the wear-resistant ring (4) is provided with a second protruding part, and along the radial direction of the piston head (3), the second protruding part is inserted into the second annular groove in an inseparable mode.

5. The anti-separation piston vacuum pump according to claim 4, characterized in that The number of the second annular grooves can be multiple, the number of the second protruding parts is equal to the number of the second annular grooves, and along the radial direction of the piston head (3), any second protruding part is inserted into any second annular groove in an inseparable mode.

6. The anti-disengagement piston vacuum pump of claim 5, wherein, The outer surface of the piston head (3) is further provided with a containing groove (7), the containing groove (7) is provided with a sealing filling medium (8), along the radial direction of the piston head (3), a first gap is formed between the sealing filling medium (8) and the inner wall of the cylinder (1), and the end part of the first gap is inserted and filled by the wear-resistant ring (4).

7. The anti-disengagement piston vacuum pump of claim 6, wherein, The number of the containing grooves (7) is two, and along the axial direction of the piston head (3), the first annular groove (6) is located between the two containing grooves (7).

8. The anti-disengagement piston vacuum pump of claim 7, wherein, The containing groove (7) is an annular groove structure and is distributed around the axis of the piston head (3).

9. The anti-separation piston vacuum pump according to any of claims 1 to 8, characterized in that The piston head (3) is further provided with an open sealing ring (9), which is arranged between the circumferential outer surface of the piston head (3) and the hole inner wall of the cylinder hole (2) along the radial direction of the piston head (3) and is in interference fit with the circumferential outer surface of the piston head (3) and the hole inner wall of the cylinder hole (2) respectively. Along the axial direction of the piston head (3), the wear-resistant ring (4) is located on one side of the open sealing ring (9).

10. The anti-disengagement piston vacuum pump of claim 9, wherein, The circumferential outer surface of the piston head (3) is provided with a clamping groove (10), and one part of the open sealing ring (9) is clamped in the clamping groove (10).

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