A drawbar device suitable for central drive

Abstract

The present application relates to a kind of puller device suitable for central transmission, belong to mechanical field.Puller device includes upper tray, lower tray, pull catch, big bolt, small bolt, long bolt;The screw rod of big bolt is sequentially from center through upper tray and lower tray, lower tray is fixed with the tail end of the screw rod of big bolt, lower tray is used to press against simulation shaft, so that lower tray and simulation shaft keep relatively immobile;Upper tray is threadedly cooperated with the screw rod of big bolt, the outer edge of upper tray is uniformly fixed with three identical pull catch, pull catch is turned outwards, the part of pull catch turned outwards is hooked in central transmission gear inner diameter groove;Threaded hole for cooperating with small bolt is arranged in the middle of pull catch;Long bolt is sequentially through lower tray and upper tray 1), the screw rod tail end of long bolt is fixed on the lower end surface of upper tray, the lower end surface of lower tray is set T-shaped slot for accommodating the nut of long bolt in the position of the screw rod of long bolt;When lower tray and simulation shaft keep relatively immobile, pull catch is aligned with central transmission gear inner diameter groove, small bolt moves downwards until pull catch is hooked in central transmission gear inner diameter groove, and central transmission gear is screwed out under the action of big bolt.

Description

Technical Field

[0001] This invention relates to a puller device suitable for central drive, belonging to the field of machinery. Background Technology

[0002] On the test bench for the engine transmission system, the central drive is typically fixed to the equipment connecting shaft via a drive central drive gear for power transmission. The connection is interference-fit, requiring heating of the gear and cooling of the equipment connecting shaft during assembly. This makes disassembly exceptionally difficult; using a standard rigid hammer can easily damage the bearings and gear supports. Therefore, a specialized puller device was designed to easily separate the central drive from the equipment connecting shaft. Summary of the Invention

[0003] The purpose of this invention is to design a puller device suitable for central drive, which can separate the central drive and the equipment connecting shaft, avoid damage to bearings or equipment, and improve disassembly efficiency.

[0004] Technical solution:

[0005] A puller device suitable for central drive includes an upper tray, a lower tray, a puller, a large bolt, a small bolt, and a long bolt;

[0006] The large bolt's shank passes through the upper and lower trays sequentially from the center. The lower tray is fixed to the tail end of the large bolt's shank and is used to hold the simulation shaft in place, keeping the lower tray and the simulation shaft relatively stationary. The upper tray is threadedly engaged with the large bolt's shank. Three identical pull claws are evenly fixed to the outer edge of the upper tray. The pull claws are turned outwards, and the outward-turned parts of the pull claws hook into the inner diameter groove of the central transmission gear. A threaded hole for the small bolt is provided in the middle of the pull claw. The long bolt passes through the lower tray and the upper tray 1) sequentially. The tail end of the long bolt's shank is fixed to the lower end face of the upper tray. A T-shaped groove for accommodating the long bolt's nut is provided on the lower end face of the lower tray at the position of the long bolt's shank.

[0007] When the current tray and the simulation shaft remain relatively stationary, and the puller is aligned with the inner diameter groove of the central drive gear, the small bolt moves downward until the puller hooks onto the inner diameter groove of the central drive gear, and the central drive gear is unscrewed under the action of the large bolt.

[0008] The device also includes: a lock nut and a cotter pin;

[0009] Tighten the lock nut and cotter pin to lock the lower tray to the end of the bolt of the large bolt.

[0010] The upper tray 1 has three evenly distributed U-shaped grooves for installing pull claws; the U-shaped grooves have small holes for bolts to pass through and fix the pull claws; the upper tray has hexagonal nuts for use with tools to fix it and counteract the tightening torque along the circumferential direction.

[0011] The puller needs to select a material with high hardness and large tensile strength, and is processed with a pull hook to facilitate hooking the groove in the inner wall of the central transmission gear, is processed with a threaded hole to facilitate passing through a small bolt to improve the reliability of the connection between the puller and the inner wall of the central transmission gear, and is processed with a light hole to facilitate fixing with the upper tray through a bolt.

[0012] The annular step of the lower tray is designed according to the size of the equipment connecting shaft and is also the main force bearing surface of the puller device and the equipment connecting shaft; the lower tray is processed with two light holes to facilitate the connection of the long bolt and the upper tray, and to avoid the flying out of the lower tray during use.

[0013] The large bolt is selected from a material with high hardness and large tensile strength, is the core component of the puller device, and can convert the tightening torque in the circumferential direction into axial thrust through the threads of the large bolt; the large bolt is processed with a small hole to facilitate the installation of a split pin and to avoid the falling of the locking nut.

[0014] The cross-sectional area of the puller should be not less than 27cm 2 .

[0015] The simulation shaft is made of 40CrNiMoA, and the central transmission gear is made of 15Cr14Co12Mo5Ni.

[0016] Advantages:

[0017] The application provides a puller device suitable for central transmission, which can separate the central transmission and the equipment connecting shaft, avoid damaging the bearing or the equipment, and improve the disassembly efficiency. At the same time, appropriate force application area, force and other parameters are designed according to the structure, so that the puller device can be designed according to different conditions. DETAILED DESCRIPTION

[0018] Figure 1 The puller device provided in the application is a front view;

[0019] Figure 2 The puller device provided in the application is a schematic view of the upper tray of the puller device;

[0020] Figure 3 The puller device provided in the application is a schematic view of the puller of the puller device;

[0021] Figure 4 The puller device provided in the application is a schematic view of the lower tray of the puller device;

[0022] Figure 5 The puller device provided in the application is a schematic view of the large bolt of the puller device. DETAILED DESCRIPTION

[0023] The application provides a puller device suitable for central transmission, which is characterized by comprising an upper tray 1, a lower tray 2, a puller 3, a large bolt 4, a small bolt 5, a long bolt 6, a locking nut 7 and a split pin 8.

[0024] The upper tray 1 is processed with three uniformly distributed U-shaped grooves 9, which are used for installing the puller 3; the U-shaped grooves 9 are processed with first small holes 11, which are used for fixing the puller 3 through the bolts; and the upper tray 2 is processed with hexagonal nuts 10, which are used for fixing by using tools and offsetting the tightening torque in the circumferential direction.

[0025] The puller 3 needs to be selected from materials with high hardness and large tensile strength, is processed with a pull hook 12, which is used for hooking the groove in the inner wall of the central transmission gear, is processed with a threaded hole 13, which is used for improving the reliability of the connection between the puller and the inner wall of the central transmission gear through the small bolt 5, and is processed with a first light hole 14, which is used for fixing with the upper tray 1 through the bolt.

[0026] The annular step 15 processed on the lower tray 2 can be designed according to the size of the equipment connecting shaft and is also the main bearing surface of the puller device and the equipment connecting shaft; the lower tray 2 is processed with two second light holes 16, which are used for connecting the long bolt 6 and the upper tray 1, so as to avoid the flying out of the lower tray 2 during use.

[0027] The large bolt 4 needs to be selected from materials with high hardness and large tensile strength and is the core component of the puller device, the threaded hole of the large bolt 4 can convert the tightening torque in the circumferential direction into axial thrust, and the second small hole 17 is processed on the large bolt 4, which is used for installing the split pin 8 and avoiding the falling of the locking nut 7.

[0028] During use, the large bolt 4 is rotated and screwed into the center thread of the upper tray 1, the lower tray 2 is assembled in sequence, the locking nut 7 is tightened, the split pin 8 is locked, the height difference between the lower tray 2 and the puller 3 is adjusted by rotating the large bolt 4, until the position relationship between the central transmission gear and the equipment connecting shaft is matched, the puller 3 is hooked to the groove in the inner wall of the central transmission gear, the small bolt 5 is lifted up (to ensure that the puller cannot be pulled out of the groove in the inner wall of the central transmission gear), the annular outer wall of the lower tray 2 is in contact with the equipment connecting shaft, and the long bolt 6 is installed (to protect the lower tray 2 from flying out). After being ready, the upper tray 1 is fixed by using tools so as not to rotate in the circumferential direction, the large bolt 4 is screwed in, at this time, the rotating torque is converted into axial thrust through the thread, the puller 3 is reversely stretched, and thus the central transmission gear is separated from the equipment connecting shaft.

[0029] The cross-sectional area of the puller 3 should be not less than 27cm 2 , wherein the simulation shaft material is 40CrNiMoA, the inner diameter d i = 99.8mm;

[0030] The central transmission gear material is 15Cr14Co12Mo5Ni, the outer diameter d a = 133.2 mm;

[0031] The combined diameter d of the central transmission gear and the simulation shaft f = 119.8 mm, the combined length l f = 22 mm, the combined surface roughness R aa = R ai = 0.0032 mm,

[0032] The friction factor μ of the friction pair = 0.11, the elastic modulus E a = E i = 210000 MPa, the Poisson's ratio V a = V i = 0.3; C a = 9.826, C i = 9.226;

[0033] The transmitted force

[0034] The minimum joint pressure

[0035] The diameter change amount of the central transmission gear:

[0036]

[0037] The diameter change amount of the simulation shaft

[0038] The minimum interference amount δmax= e amin + e imin = 0.0636

[0039] The press-in force of the central transmission gear:

[0040]

[0041] The pull-out force of the central transmission gear:

[0042] P 拉出力 ≥ 1.5*P 拉入力 = 1.5*5327 kN = 7991 kN.

[0043] The puller device is provided with 3 pullers, and the pull force of each puller is P 拉出力 / 3 = 2664 kN.

[0044]

Claims

1. A drawbar arrangement suitable for use with a central drive, characterised in that, It comprises an upper tray (1), a lower tray (2), a puller (3), a large bolt (4), a small bolt (5) and a long bolt (6). The screw rod of the large bolt (4) passes through the upper tray (1) and the lower tray (2) in sequence, the lower tray (2) is fixed to the tail end of the screw rod of the large bolt (4), and the lower tray (2) is used for abutting against the simulation shaft, so that the lower tray (2) is kept relatively stationary with the simulation shaft; the upper tray (1) is in threaded cooperation with the screw rod of the large bolt (4), and the outer edge of the upper tray (1) is uniformly fixed with three identical pullers (3), the puller (3) is turned outward, and the turned outward part of the puller (3) is hooked on the inner diameter groove of the central transmission gear; the middle part of the puller (3) is provided with a threaded hole matched with the small bolt (5); the long bolt (6) passes through the lower tray (2) and the upper tray (1) in sequence, the tail end of the screw rod of the long bolt (6) is fixed to the lower end face of the upper tray (1), and the lower end face of the lower tray (2) is provided with a T-shaped groove for accommodating the nut of the long bolt (6) at the position of the screw rod of the long bolt (6). When the lower tray (2) is kept relatively stationary with the simulation shaft and the puller (3) is aligned with the inner diameter groove of the central transmission gear, the small bolt (5) moves downward until the puller (3) is hooked on the inner diameter groove of the central transmission gear, and the central transmission gear is screwed out under the action of the large bolt (4).

2. The apparatus of claim 1, wherein, The device further comprises a locking nut (7) and a split pin (8). The locking nut (7) and the split pin (8) lock the tail end of the screw rod of the large bolt (4) and the lower tray (2).

3. The apparatus of claim 1, wherein, The upper tray (1) is processed with three uniformly distributed U-shaped grooves (9), which are used for installing the puller (3); the U-shaped groove (9) is processed with a first small hole (11), which is used for passing through the bolt to fix the puller (3); the upper tray (1) is processed with a hexagonal nut (10), which is used for fixing by using a tool to offset the tightening torque in the circumferential direction.

4. The apparatus of claim 1, wherein, The puller (3) needs to be made of a material with high hardness and high tensile strength, and is processed with a hook (12) to facilitate hooking on the groove on the inner wall of the central transmission gear; the puller (3) is processed with a threaded hole (13) to facilitate passing through the small bolt (5) and improve the reliability of the connection between the puller and the central transmission gear; the puller (3) is processed with a first light hole (14) to facilitate fixing with the upper tray (1) by passing through the bolt.

5. The apparatus of claim 1, wherein, The annular step (15) processed on the lower tray (2) is designed according to the size of the equipment connecting shaft and is also the main force bearing surface of the puller device and the equipment connecting shaft; the lower tray (2) is processed with two second light holes (16) to facilitate the connection of the long bolt (6) and the upper tray (1) and avoid the lower tray (2) from flying out during use.

6. The apparatus of claim 1, wherein, The large bolt (4) is made of a material with high hardness and high tensile strength and is the core component of the puller device, and the screw thread of the large bolt (4) can convert the tightening torque in the circumferential direction into axial thrust; the large bolt (4) is processed with a second small hole (17) to facilitate installing the split pin (8) and avoid the locking nut (7) from falling off.

7. The apparatus of claim 1, wherein, The cross-sectional area of the pull (3) should not be less than 27 cm 2 .

8. The apparatus of claim 1, wherein, The simulation shaft is made of 40CrNiMoA, and the central transmission gear is made of 15Cr14Co12Mo5Ni.

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