CN115929882A

CN115929882A - Planetary gear box shock-resistant structure containing disc spring bolt

Info

Publication number: CN115929882A
Application number: CN202211595767.4A
Authority: CN
Inventors: 胡聪芳; 刘干; 夏乾; 彭涛
Original assignee: Xiangtan University
Current assignee: Xiangtan University
Priority date: 2022-12-12
Filing date: 2022-12-12
Publication date: 2023-04-07

Abstract

The invention discloses an impact-resistant structure of a planetary gear box containing disc spring bolts. The bolt applies pretightening force, and initial contact pressure is provided on the contact surfaces of the lower surfaces of the upper box body and the disc spring and the lower box body and the inner gear ring. Under the action of transverse shearing impact load, the friction force provided by the pretightening force of the bolt is not enough to balance the shearing force borne by the inner gear ring, the inner gear ring slides, the upper surface and the lower surface of the disc spring are respectively contacted with the lower surface of the nut and the upper surface of the upper box body, the friction energy loss is increased, the transverse impact energy is reduced, and the gear teeth are prevented from being broken; under the action of longitudinal tensile impact load, the disc spring deforms to absorb longitudinal impact energy and prevent the bolt from being longitudinally broken; through adjusting bolt figure, bolt pretightning force and dish spring figure, the control structure prevents that the ring gear from excessively sliding to the absorption of impact energy, guarantees bolt intensity.

Description

Planetary gear box shock-resistant structure containing disc spring bolt

Technical Field

The invention relates to an impact-resistant structure of a planetary gear box containing a disc spring bolt.

Background

High-end power equipment such as an aircraft engine, rail transit, a megawatt wind turbine generator, a new energy automobile and a ship is a fundamental, strategic and leading industry which is concerned with national economy and national safety, and the high-end power equipment is mostly transmitted by adopting a planetary gear which has a compact structure, a large transmission ratio, high efficiency and strong bearing capacity.

The load working condition of the planetary transmission is more complicated than that of the common gear transmission, the variable load is always born, and the problem of collision and impact in the gear system is very complicated. The transient impact force generated by the collision of the gear teeth under the action of the peak load is extremely large, the impact stress between the gear teeth and the transient stress borne by a system connecting member are increased sharply, and the structure designed by the equivalent load cannot meet the strength requirement under the action of the peak impact load, so that the structure of the gear box needs to be optimized, and the reliability of the planetary gear box structure under the peak impact load is improved. The utility model provides a planetary gear case shock-resistant structure who contains dish spring bolt, this structure can effectively solve under the peak value impact load effect ring gear and planet wheel teeth of a cogwheel rupture or bolt fracture phenomenon.

Disclosure of Invention

The invention aims to provide an impact-resistant structure of a planetary gear box containing a disc spring bolt.

The invention adopts the technical scheme that the planetary gear box impact-resistant structure containing the disc spring bolt is characterized in that the gear box is of a separated structure, an inner gear ring is connected with an upper box body and a lower box body through bolts, and the lower box body is fixed. The disc springs are respectively arranged between the bolt and the nut and the upper box body.

The invention has the following technical effects: 1. under the normal operating mode, the pretension frictional force and the initial positive pressure that are provided by the bolt pretightning force overcome outside shear load and tensile load, and the ring gear does not squint, and structural strength can guarantee. 2. Under the action of transverse shearing load, the lower surface of a bolt nut and the upper surface of the disc spring as well as the upper surface of the upper box body and the lower surface of the disc spring provide friction force, transverse impact energy is consumed, the teeth of the inner gear ring are not broken, and the bolt is not sheared and damaged. 3. Under the action of longitudinal impact load, the disc spring is elastically deformed, longitudinal impact energy is lost, and the bolt is prevented from being longitudinally broken. 4. Through adjusting bolt figure, bolt pretightning force and dish spring figure, the control structure prevents that the ring gear from excessively sliding to the absorption of impact energy, guarantees bolt intensity.

Drawings

FIG. 1 is a perspective view of the structure of the assembly of the present invention;

FIG. 2 is a schematic cross-sectional view of a disc spring according to the present invention;

FIG. 3 isbase:Sub>A schematic view ofbase:Sub>A partial cross-sectional structure A-A of the present invention.

Detailed Description

The embodiment of the invention provides an impact-resistant structure of a planetary gear box containing a disc spring bolt, which comprises the following components in percentage by weight as shown in figure 1: the device comprises an upper box body 1, a bolt 2, an inner gear ring 3, a lower box body 4, a disc spring 5, a planet wheel 6 and a sun wheel 7.

The gear box is of a separated structure, an inner gear ring 3 is connected with an upper box body 1 and a lower box body 4 through bolts 2, and the lower box body is fixed. Disc springs 5 are respectively installed between the bolts 2 and the upper case 1.

Under the normal working condition, when the planetary gear train runs, the gear system is subjected to circumferential shearing force and axial force due to uneven load among gear trains, the pretightening friction force and the initial positive pressure provided by the pretightening force of the bolts overcome the external shearing load and the tensile load, and the inner gear ring does not deviate because the gear box system is designed according to equivalent load, so that the structural strength is ensured.

Under the action of shearing impact load, limit impact load acts on the gear teeth instantly, and if the structural rigidity is too high, the transient impact energy received by the gear teeth is very large enough to cause plastic deformation and even breakage of the gear teeth. To ensure that the gear teeth are not damaged, lateral impact energy needs to be absorbed. The most of transverse impact energy is absorbed by the joint surface of the bolt and the nut and the upper surface of the disc spring as well as the upper surface of the upper box body and the disc spring, one part of transverse impact energy is stored in the bolt and is converted into strain energy of the bolt, the last part of transverse impact energy is absorbed by the gear teeth, the impact energy at the moment is not enough to enable the gear teeth to generate plastic deformation, and the gear teeth are not damaged.

Under the action of longitudinal impact load, peak load acts on the bolt, and the stress of the bolt at the moment comprises tensile stress, transverse shear stress and impact tensile stress generated by self pretightening force, so that the bolt is subjected to tensile fracture. In order to ensure that the bolt is not damaged, the bolt needs to be flexibly buffered. The disc spring is deformed by the work of the impact load, most of longitudinal impact energy is converted into the elastic energy of the disc spring, the rest part of longitudinal impact energy is converted into the strain energy of the bolt, the bolt is still in an elastic deformation state at the moment, and the stress is smaller than the yield limit value.

Under the action of peak load, the pretightening force of the bolts and the number of the bolts are increased, the rigidity of the structure is increased, the gear box structure is ensured not to generate large slippage, and the large deformation shearing damage of the bolts is prevented; the number of disc springs between the bolts and the upper box body is increased, the friction surface is increased, the absorption of transverse shearing impact energy is increased, and the impact energy acting on the gear teeth is reduced; the dish spring quantity increases, and the longitudinal flexibility of gear box increases, prevents that the bolt is tensile to be destroyed.

Claims

1. The utility model provides a contain planetary gear case shock resistance structure of dish spring bolt, the gear box adopts the disconnect-type structure, falls into box (1), ring gear (3) and lower box (4), has all opened bolt hole, its characterized in that on last box (1), ring gear (3) and lower box (4): a bolt (2) arranged in a bolt hole applies proper bolt pretightening force to connect the upper box body (1), the disc spring (5), the inner gear ring (3) and the lower box body (4), and the disc spring is arranged between a bolt nut and the upper box body; at least one disc spring (5) is arranged between the bolt (2) and the upper box body (1).