Metallic ball hinge for a roll-resisting device of a railway vehicle

Abstract

The application discloses a metal ball hinge for a rail vehicle anti-rolling device, which comprises a ball seat, a ball pin and a ball bowl; the ball head of the ball pin is arranged in the ball seat through the ball bowl; the ball bowl comprises a first ball bowl arranged at the bottom of the ball seat, and an upper side of the first ball bowl is provided with a second ball bowl; the radii of the first ball bowl and the second ball bowl are both greater than the radius of the ball head, so that there are at least two contact points between the ball head and the ball bowl, which are respectively located in the first ball bowl and the second ball bowl; an end cover is arranged at the upper side of the ball seat; an elastic member is arranged between the second ball bowl and the end cover; an adjusting bolt is arranged through the middle of the end cover, and the screw end of the bolt abuts against the elastic member. The application improves the durability of the ball hinge, prolongs the service life of the ball hinge, reduces the probability of abnormal sound and reduces the life cycle cost of the vehicle.

Description

Technical Field

[0001] This invention relates to a metal ball joint for an anti-roll device in rail vehicles, belonging to the field of rail transit vehicle technology. Background Technology

[0002] The anti-roll device for rail vehicles consists of components such as an anti-roll torsion bar, a swing arm, a bearing housing, and a connecting rod assembly, and can be installed in two ways. One method is to mount the torsion bar and the swing arm onto the car body underframe via the bearing housing, and then connect the swing arm to the bogie frame via ball joints at both ends of the connecting rod assembly.

[0003] To accommodate the rotational motion between the car body and bogie during vehicle curve movement and ensure the boom can rotate freely, the ball joints at both ends of the connecting rod assembly must bear tensile and compressive forces along the connecting rod axis. The ball pins inside the ball joints will rotate relative to the ball joint body at a certain angle. Based on the working characteristics of the ball joint structure, the force direction of the ball joint is along the connecting rod axis.

[0004] like Figure 1 As shown, the existing metal ball joint consists of components such as the ball joint body, dust cover, ball pin, ball cup, and end cap.

[0005] There are two types of ball joint structures: with and without springs. While the ball joint with a spring offers some clearance adjustment capability, its use of a helical metal spring, due to space constraints, results in insufficient spring stiffness and prevents adjustment of the spring clamping force during subsequent use. Grease between the ball cup and the ball pin must be added before assembly; once assembled, the ball joint cannot be replenished with grease before it is scrapped. In long-term operation, because the radii of the ball cup raceway and the ball pin head are the same, the outermost part of the ball pin head makes single-point contact with the ball cup. This leads to several technical problems: concentrated stress on the ball pin and ball cup, resulting in accelerated wear; inconvenient grease replenishment leading to lubrication failure; increased impact load due to increased clearance between the ball pin and ball cup after wear; and difficulty in achieving clearance adjustment. Summary of the Invention

[0006] The present invention aims to provide a metal ball joint for anti-roll device of rail vehicles, which improves the durability of the ball joint, extends its service life, reduces the probability of abnormal noise, and reduces the total life cycle cost of the vehicle.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A metal ball joint for an anti-rollover device of a rail vehicle includes a ball seat, a ball pin, and a ball cup; the ball head of the ball pin is disposed in the ball seat through the ball cup; characterized in that: the ball cup includes a first ball cup disposed at the bottom of the ball seat, and a second ball cup disposed on the upper side of the first ball cup; the radii of the first ball cup and the second ball cup are both larger than the radius of the ball head, so that the ball head always has at least two contact points with the ball cup, respectively located in the first ball cup and the second ball cup.

[0009] Therefore, the metal ball joint for the anti-rollover device of the rail vehicle of the present invention includes a ball cup with a split structure of two halves, and the radii of the first ball cup and the second ball cup are both larger than the radius of the ball head. The raceway between the ball head and the ball cup is composed of two intersecting circular arcs. The contact position between the ball cup and the ball pin can be changed by adjusting the radius of the raceway curve, so as to achieve two-point contact between the ball pin and the raceway, reduce the contact stress, and increase the durability of the ball cup.

[0010] According to embodiments of the present invention, the present invention can be further optimized, and the optimized technical solution is as follows:

[0011] In one specific embodiment, the radii of the first and second ball bowls are both 0.52-0.53 times the diameter of the ball head.

[0012] The two spherical surfaces of the first and second ball cups intersect outside the ball head of the ball pin. Therefore, there are always two contact points between the ball pin and the raceway, located in the first and second ball cups respectively. At this point, the fit between the ball cup and the ball pin is no longer limited to a single contact line area, but rather the contact stress between the ball pin and the ball cup is shared by two contact line areas at the upper and lower contact points. Due to the change in contact points, the contact stress is significantly reduced, enhancing the wear resistance of the ball cups and greatly increasing the life of the raceway.

[0013] In one specific embodiment, the upper end of the ball head is provided with an oil inlet hole; the ball head is provided with a vertical first oil passage communicating with the oil inlet hole, and the ball head is also provided with a horizontal second oil passage communicating with the first oil passage; the two ends of the second oil passage respectively penetrate the left and right sides of the ball head.

[0014] In one specific embodiment, a leak-proof plug is provided inside the oil inlet hole.

[0015] After removing the bolts, lubricating grease can be replenished through the grease nipple on the ball head via the screw hole. The oil passage hole inside the ball pin can inject lubricating grease into the contact area between the ball pin and the raceway, thereby enabling the ball joint to be periodically lubricated when the connecting rod assembly needs to be disassembled, ensuring the lubrication condition between the ball cup and the ball pin.

[0016] In one specific embodiment, there is a certain gap between the elastic element and the end cap; there is a certain gap between the first ball cup and the second ball cup.

[0017] When the connecting rod is subjected to excessive impact force, the axial force generated by the ball head on the raceway causes the ball cup to displace towards the elastic element at the end of the ball joint. This allows the deformation of the disc spring to elastically alleviate the axial impact force on the connecting rod, thus preventing damage to the raceway caused by excessive impact force.

[0018] During installation, the two hemispherical cups are not in direct contact; a gap of 0.3mm-0.5mm is left between them. The contact pressure of the disc spring on the cup and the ball is adjusted by bolts to eliminate the gap between the ball and the raceway.

[0019] In one specific embodiment, an end cap is provided on the upper side of the ball seat; an elastic element is provided between the second ball cup and the end cap; an adjusting bolt is provided through the middle of the end cap, and the end of the bolt abuts against the elastic element.

[0020] To reduce the impact force of the ball head on the ball cup when subjected to excessive impact, the clamping force of the elastic element can be adjusted by tightening or loosening the bolts. This can prevent the ball pin from exerting excessive impact on the raceway and also avoid interference with surrounding components when the ball joint rotates.

[0021] In one specific embodiment, the elastic element is a butterfly spring, and a circular hole is opened in the middle of the elastic element. The diameter of the circular hole is smaller than the diameter of the bolt's screw.

[0022] To facilitate the injection of lubricating oil into the ball joint, a round hole is provided in the middle of the elastic element. After the bolt is removed, lubricating grease can be injected into the contact area between the ball pin and the raceway through the oil passage hole of the ball head via this round hole, thereby realizing the periodic oiling of the ball joint and ensuring the lubrication state between the ball cup and the ball pin.

[0023] In one specific embodiment, a bushing is provided between the elastic element and the second ball cup.

[0024] In one specific embodiment, a gasket is provided between the bolt head and the end cap.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] 1) In this invention, the fit between the ball cup and the ball pin is no longer limited to a single contact line area, but rather the contact stress between the ball pin and the ball cup is shared by two contact line areas at two different contact points. This change in contact points significantly reduces contact stress, enhances the wear resistance of the ball cup, and substantially improves the lifespan of the raceway.

[0027] 2) The butterfly spring in the metal ball joint of this invention, combined with the upper clamping bolt, can not only avoid the ball head from having an excessive impact on the raceway, but also make it easy to adjust the gap and clamping force between the butterfly spring and the ball cup. In terms of spatial structure, it also avoids the ball pin from interfering with surrounding components within the maximum rotation range.

[0028] 3) The present invention can replenish lubricating grease to the grease nipple on the ball head through the screw hole. The lubricating oil can flow to the raceway between the ball head and the ball cup through the channel set inside the ball head. This can be done without disassembling the connecting rod assembly, thus ensuring the timeliness of grease replenishment.

[0029] 4) This invention improves the durability of the ball joint, extends its service life, reduces the probability of abnormal noise, and reduces the total life cycle cost of the vehicle. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the ball joint structure in the background art of this invention;

[0031] Figure 2 This is a schematic diagram of the structure of the present invention;

[0032] Figure 3 yes Figure 2 A magnified view of a section at point M.

[0033] In the figure

[0034] 1-Ball seat; 2-Ball pin; 21-Ball head; 211-Oil inlet; 3-Ball cup; 31-First ball cup; 32-Second ball cup; 4-End cap; 5-Elastic element; 51-Round hole; 6-Bolt; 7-First oil passage; 8-Second oil passage; 9-Plug; 10-Bushing; 11-Gasket; S1-First contact point; S2-Second contact point; S3-Outermost point of ball head; S4-Raceway intersection. Detailed Implementation

[0035] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. For ease of description, the terms "upper," "lower," "left," and "right" used below only indicate that they correspond to the upper, lower, left, and right directions in the accompanying drawings and do not limit the structure.

[0036] like Figure 2As shown, the metal ball joint for the anti-rollover device of the rail vehicle in this embodiment includes a ball seat 1, a ball pin 2, and a ball cup 3; the ball head 21 of the ball pin 2 is disposed in the ball seat 1 through the ball cup 3; the ball cup 3 includes a first ball cup 31 disposed at the bottom of the ball seat 1, and a second ball cup 32 disposed on the upper side of the first ball cup 31 for covering the ball head 21; the radii of the first ball cup 31 and the second ball cup 32 are both larger than the radius of the ball head 21; an end cap 4 is disposed on the upper side of the ball seat 1; an elastic element 5 is disposed between the second ball cup 32 and the end cap 4; an adjusting bolt 6 is disposed through the middle of the end cap 4, and the end of the bolt 6 abuts against the elastic element 5.

[0037] Specifically, the radii of the first ball cup 31 and the second ball cup 32 are both 0.52 times the diameter of the ball head 21. The elastic element 5 is a disc spring.

[0038] The metal ball joint of the anti-rollover device for rail vehicles in this embodiment includes a ball cup 3 with a split structure of two halves. The radii of the first ball cup 31 and the second ball cup 32 are both larger than the radius of the ball head 21. The raceway between the ball head 21 and the ball cup 3 is composed of two intersecting arcs. The contact position between the ball cup 3 and the ball pin 2 can be changed by adjusting the radius of the raceway curve, so as to achieve two-point contact between the ball pin 2 and the raceway (first contact point S1 and second contact point S2).

[0039] like Figure 3 As shown, there are always two contact points between the ball pin 2 and the raceway, located at the first ball cup 31 and the second ball cup 32 respectively. In this case, the fit between the ball cup 3 and the ball pin 2 is no longer limited to a single contact line area, but rather the contact stress between the ball pin 2 and the ball cup 3 is shared by two contact line areas at the upper and lower contact points. Due to the change in contact points, the contact stress is significantly reduced, enhancing the wear resistance of the ball cup 3 and greatly improving the lifespan of the raceway.

[0040] To ensure timely grease replenishment without disassembling the connecting rod assembly, a lubrication system is provided inside the ball joint, including an oil inlet hole 211 at the upper end of the ball head 21; a vertical first oil passage 7 communicating with the oil inlet hole 211 is provided inside the ball head 21, and a horizontal second oil passage 8 communicating with the first oil passage 7 is also provided inside the ball head 21; the two ends of the second oil passage 8 respectively penetrate the left and right sides of the ball head 21.

[0041] Specifically, a leak-proof plug 9 is provided inside the oil inlet 211.

[0042] After removing bolt 6, lubricating grease can be injected into the contact area between ball pin 2 and raceway through oil inlet hole 211 inside ball head 21, thereby achieving regular lubrication of ball joint and ensuring lubrication between ball cup and ball pin.

[0043] like Figure 3 As shown, the space between the outermost point S3 of the ball head and the intersection point S4 of the raceway can store a certain amount of grease. Combined with the oil replenishment operation, it can continuously and effectively improve the lubrication state between the ball pin and the raceway, reduce the friction between the ball pin and the raceway, and reduce the wear of the friction pair.

[0044] A 1mm gap is left between the elastic element 5 and the end cap 4. When the connecting rod is subjected to excessive impact force, the axial force generated by the ball head 21 on the raceway causes the ball cup 3 to move towards the elastic element 5 at the end of the ball joint. This allows the deformation of the disc spring to elastically relieve the axial impact force on the connecting rod, thus avoiding damage to the raceway caused by excessive impact force.

[0045] During installation, the two hemispherical cups are not in direct contact; a gap of 0.3mm-0.5mm is left between them. The gap between the ball head and the raceway can be eliminated by adjusting the contact pressure of the disc spring on the ball cup and the ball using bolts.

[0046] An adjusting shim is provided between the adjusting bolt and the end cover, and the number of shims can be increased or decreased as needed.

[0047] Since the maximum turning angle in actual vehicle operation is generally less than 40°, to allow for a certain safety margin, the maximum turning angle of the ball joint in this invention is considered to be 45° (i.e., a single-sided ball joint rotation of 22.5°). After motion analysis, rotating the ball pin 22.5° clockwise and counterclockwise respectively, there is no interference between the ball pin and the surrounding components, and the ball cup does not protrude from the ball body.

[0048] The anti-rollover device for rail vehicles of the present invention uses a metal ball joint with a split structure, with a certain gap between the ball joints. The raceway curve consists of two intersecting arc curves with a radius of 0.52-0.53 times the diameter of the ball head. Under the action of the disc spring, a two-point contact is formed between the ball pin and the raceway of the ball joint, avoiding single-point contact.

[0049] The ball joint is equipped with a butterfly spring, and the spring force is adjusted by the bolt above. The butterfly spring structure allows the ball cup raceway to move axially elastically under excessive impact load, thus avoiding damage to the raceway from excessive impact load.

[0050] The ball joint is equipped with an oil injection channel. After the bolts are removed, lubricating grease can be injected into the contact area between the ball pin and the raceway through the oil passage hole in the ball pin. This allows for regular oiling of the ball joint, ensuring the lubrication between the ball cup and the ball pin.

[0051] The above embodiments should be understood as being used only to illustrate the present invention more clearly, and not to limit the scope of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art fall within the scope defined by the appended claims.

Claims

1. A metal ball joint for a roll stabilizer of a railway vehicle, comprising a ball seat (1), a ball pin (2), a ball cup (3); a ball head (21) of the ball pin (2) is arranged in the ball seat (1) through the ball cup (3); characterized in that: The ball bowl (3) comprises a first ball bowl (31) arranged at the bottom of the ball seat (1), and an upper side of the first ball bowl (31) is provided with a second ball bowl (32); the radii of the curved surfaces of the first ball bowl (31) and the second ball bowl (32) are greater than the radius of the ball head (21), so that the ball head (21) is always in contact with the ball bowl (3) at at least two contact points, respectively located in the first ball bowl (31) and the second ball bowl (32); The ball head (21) is provided with an oil inlet hole (211) at the upper end thereof; the ball head (21) is provided with a vertical first oil channel (7) in communication with the oil inlet hole (211); the ball head (21) is further provided with a horizontal second oil channel (8) in communication with the first oil channel (7); both ends of the second oil channel (8) pass through the left and right sides of the ball head (21); and the oil inlet hole (211) is provided with a leak-proof plug (9).

2. The metal ball joint for anti-roll devices of rail vehicles according to claim 1, characterized in that: The radii of the first ball bowl (31) and the second ball bowl (32) are 0.52-0.53 times the diameter of the ball head (21).

3. The metal ball joint for anti-roll devices of rail vehicles according to claim 1, characterized in that: The upper side of the ball seat (1) is provided with an end cover (4); an elastic member (5) is arranged between the second ball bowl (32) and the end cover (4); and the end cover (4) is provided with an adjusting bolt (6) penetrating through the middle part thereof, and the screw end of the bolt (6) abuts against the elastic member (5).

4. The metal ball joint for anti-roll devices of rail vehicles according to claim 3, characterized in that: The elastic member (5) is a butterfly spring, and the middle part of the elastic member (5) is provided with a circular hole (51) with a diameter smaller than the diameter of the screw rod of the bolt (6).

5. The metal ball joint for anti-roll device of railway vehicle according to claim 3, characterized in that: The elastic member (5) and the end cover (4) have a certain gap therebetween.

6. The metal ball hinge for anti-roll devices of rail vehicles according to claim 1, characterized in that: The first ball bowl (31) and the second ball bowl (32) have a certain gap therebetween.

7. The metal ball hinge for anti-roll devices of rail vehicles according to claim 3, characterized in that: A bushing (10) is arranged between the elastic member (5) and the second ball bowl (32).

8. The metal ball hinge for anti-roll device of railway vehicle according to claim 3, characterized in that: A gasket (11) is arranged between the head of the bolt (6) and the end cover (4).

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