Planetary gearbox with involute sprockets and stationary roller chain

Abstract

This utility model relates to mechanical engineering, specifically to mechanical transmissions comprising gears performing planetary motion, as well as a roller chain drive. A planetary gearbox with involute sprockets comprises input and output shafts, a pinion, and a carrier, at the ends of which satellite sprockets are rotatably mounted and engaged with a roller chain. The pinion has involute external teeth and is rigidly attached to the input shaft, which is rotatably mounted on an input shaft support, while the carrier is three-beam and rigidly attached to the output shaft, which is rotatably mounted on an output shaft support coaxially with the input shaft. The satellite sprockets are sprockets with involute teeth, engaged with both the chain and the pinion.Furthermore, the gearbox includes a ring support fixed to the input shaft support via a four-pronged bracket. The roller chain is attached to the ring support with its outer links such that the centers of the roller chain pins are located on a circle, the center of which lies on the input shaft axis, and the diameter of the circle is determined by the relationship. The technical result is a change in the roller chain installation method, reducing its wear and increasing the reliability of the gearbox.

Description

[0001] The utility model relates to mechanical engineering, in particular to mechanical transmissions containing gears that perform planetary motion, as well as a roller chain.

[0002] A planetary thruster gearbox (patent DE 102012013637 A1) is known. It comprises a sun wheel consisting of several internal chain links, each of which is a pair of parallel, spaced-apart connecting plates connected by locking bushings and secured to a main support. The gearbox also comprises a ring gear, which is internally engaged with the satellite gears and is made of multiple internal chain links located between two annular base supports. Unlike a sun wheel, a ring gear has two annular support beams, between which the internal chain bars are located and to which the internal chain plates are connected.Between the sun wheel and the ring gear, there are three satellite gears, offset approximately 120° relative to the planetary gear's central axis, which mesh simultaneously with both the sun wheel and the ring gear. A disadvantage of this gearbox is the complex design of the sun wheel and ring gear, which consist of a set of inner roller chain links. This requires preliminary disassembly of the roller chain, removing the outer links, and subsequent installation of the inner chain links on ring bearings.

[0003] A planetary gearbox with involute sprockets is known (RU Patent No. 2850016 - prototype), comprising an input and output shaft, a pinion, and a carrier, at the ends of which satellite sprockets are rotatably mounted, meshing with a closed chain. The involute gear wheel is rigidly attached to the input shaft and meshes with three involute sprockets, which are rotatably mounted on axles that are rigidly attached to the ends of a three-beam carrier. The input shaft is rotatably mounted on a support for the input shaft, and the three-beam carrier is rigidly attached to a driven shaft, which is rotatably mounted on a support for the driven shaft, coaxial with the input shaft. The chain is a single-row roller chain and meshes with the three involute sprockets.Additionally, the drive shaft support has a vertical through-groove into which the roller chain retaining pin is inserted, allowing for vertical movement along the groove. The roller chain retaining pin is rigidly secured to one of the roller chain links.

[0004] The disadvantage of this gearbox is its low reliability, caused by increased wear of the chain joints, due to frequent mutual rotations of adjacent chain links when entering and exiting engagement with the satellite sprockets.

[0005] The objective of the utility model is to improve the design of the gearbox, making it possible to increase its reliability.

[0006] The technical result is a reduction in the degree of wear of the roller chain joints by changing the method of its installation.

[0007] The technical result is achieved by a planetary gearbox with involute sprockets and a stationary roller chain (hereinafter referred to as the gearbox), comprising input and output shafts, a pinion, and a planet carrier, at the ends of which satellite sprockets are rotatably mounted, which are in mesh with a closed single-row roller chain. The pinion has involute external teeth and is rigidly fixed to the input shaft, which is mounted for rotation on the input shaft support, while the planet carrier is made with three spokes and is rigidly fixed to the output shaft, which is mounted for rotation on the output shaft support coaxially with the input shaft. Moreover, the satellite sprockets are sprockets with involute teeth, which are in mesh with both the roller chain and the pinion. In addition, the gearbox comprises an annular support fixedly secured to the input shaft support by means of a four-beam bracket.Moreover, the roller chain is attached with its outer links to the ring support so that the centers of the rollers of the roller chain are located on a circle, the center of which lies on the axis of the input shaft, and the diameter of the circle d3 is determined by the formula.

[0008]

[0009] where t is the pitch of the roller chain;

[0010] W3- number of roller chain links.

[0011] Fig. 1 shows a general view of a planetary gearbox with involute sprockets and a stationary roller chain.

[0012] Fig. 2 shows a planetary gearbox with involute sprockets and a stationary roller chain (side view).

[0013] A planetary gearbox with involute sprockets and a stationary roller chain comprises an input 1 and output 2 shaft, a gear 3, a carrier 4, at the ends of which satellite sprockets 5 are mounted with the possibility of rotation, which are in engagement with a closed single-row roller chain 6. In this case, the gearbox 3 has involute external teeth and is rigidly fixed on the input shaft 1, which is mounted with the possibility of rotation on a support 7 of the input shaft 1, and the carrier 4 is made three-beam and is rigidly fixed on the output shaft 2, which is mounted with the possibility of rotation on a support 8 of the output shaft 2 coaxially with the input shaft 1. Moreover, the satellite sprockets 5 are sprockets with involute teeth, which are in engagement with the roller chain 6 and with the gear 3. In addition, the gearbox contains an annular support 9, fixedly fixed on the support 7 of the input shaft 1 by means of a four-beam bracket 10. Moreover, the roller chain 6 (Fig.1) is attached by its outer links to the ring support 9 so that the centers of the rollers of the roller chain 6 are located on a circle, the center of which lies on the axis of the input shaft 1, and the diameter of the circle d3 is determined by the formula.

[0014]

[0015] where t is the roller chain pitch;

[0016] W3- number of roller chain links 6.

[0017] The gear reducer works as follows.

[0018] Input shaft 1 rotates together with gear 3 (Fig. 1, 2). By means of involute gearing, rotation is transmitted from gear 3 to satellite sprockets 5, which, while rotating, roll along roller chain 6, causing three-beam carrier 4 to rotate together with output shaft 2. In this case, the gear ratio determined by the formula is realized

[0019] ,

[0020] where z1 is the number of teeth of gear 3;

[0021] W3- number of roller chain links 6.

[0022] Moreover, during operation, the outer links of the roller chain 6, secured to the ring support 9, remain motionless, and the inner links, during the process of rolling the satellite sprockets 5 on them, make minor movements due to the gaps in the hinges, but the mutual rotation of adjacent chain links is practically absent.

[0023] Thus, fixing the roller chain on the ring support will virtually eliminate the movement of adjacent chain links, which will significantly reduce the wear of the chain joints and increase the reliability of the gearbox.

Claims

A planetary gearbox with involute sprockets and a stationary roller chain, comprising input and output shafts, a gear, a carrier, at the ends of which satellite sprockets are mounted with the possibility of rotation, which are in engagement with a closed single-row roller chain, the gear has involute external teeth and is rigidly fixed on the input shaft, which is mounted with the possibility of rotation on the input shaft support, and the carrier is made three-beam and is rigidly fixed on the output shaft, which is mounted with the possibility of rotation on the output shaft support coaxially with the input shaft, and the satellite sprockets are sprockets with involute teeth, which are in engagement with both the closed single-row roller chain and the gear, characterized in that it contains an annular support fixed immovably to the input shaft support by means of a four-beam bracket, and the closed single-row roller chain is attached by its outer links to the annular support so thatthat the centers of the rollers of a closed single-row roller chain are located on a circle, the center of which lies on the axis of the input shaft, and the diameter of the circle d3 is determined by the formula, where t is the pitch of the roller chain; W3 - number of roller chain links.

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