RU2296255C2 - Chain transmission - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: chain transmission comprises driving sprocket (1), two driven sprockets (2) and (3), and chain that embraces the sprockets. The sprockets are shifted one with respect to the other along the shafts. The gear rims of the sprockets are mounted with a spaced relation one with respect to the other and are spaced from the plates of chain (4). Second driven sprocket (3) is mounted symmetrically to first sprocket (2) with respect to driving sprocket (1). The chain has three rows.

EFFECT: enhanced reliability and prolonged service life.

1 dwg

Description

The invention relates to the field of transmissions with flexible coupling, namely to chain transmissions with a small center distance, and can be used in drives of various machines where the use of chain transmissions of a conventional design is impossible due to the small center distance between the shafts.

Traditional chain transmissions are known which are used only with a center distance

where D _e1 and D _e2 are the diameters of the circumferences of the protrusions, and is the center distance.

If it is technically necessary to use a chain transmission of smaller dimensions with constant values of D _e1 and D _e2 , traditional transfers are impossible [1, p. 295].

The well-known chain transmission with a small interaxial distance [2], taken as a prototype, contains a drive sprocket, a driven sprocket, which are offset one relative to the other along the shafts, and a double-row chain spanning the sprockets, covering the leading sprocket one side and the driven sprocket with the other. Gear rims are installed with a gap between themselves and the chain plates. It shows that chain drives can also be used effectively with reduced center distances

The chain transmission with a small center distance is closest in technical essence and the achieved result to the proposed one and is its prototype. The number of teeth of the driving and driven sprockets may not be equal. In this case, a change in the rotation speed of the driven sprocket is achieved in comparison with the leading one. Instead of a double row chain, a single row chain can be used in the gear. In this case, the width of each sprocket should be less than half the distance between the chain plates.

However, during the operation of this transmission, there are distortions of the chain contour that disrupt normal engagement and, as a result, lead to a decrease in its quality indicators.

Distortions of the transmission chain contour with a small interaxial distance when using a single-row or double-row chain are caused by a non-planar arrangement of the sprockets, in which their mid sections are offset relative to each other, the non-planarness of the stars causes the axes to curvature and twist the chain segments that run up and down from the sprockets, the emergence of lateral forces pressing chain links to the outer ends of the sprocket gears during gear operation.

All this disrupts the transmission, reducing its efficiency, accelerates the wear of the chain and sprockets.

The objective of the invention is the elimination for a working transmission chain with a small center distance of the detected distortion of the chain loop in order to improve the quality characteristics of the transmission.

The problem is solved by the proposed chain transmission, containing the drive and driven sprockets mounted on the shafts, equipped with gear rims, and the chain spanning them, the sprockets being displaced relative to each other along the shafts, and the gear rims are installed with a gap between themselves and the chain plates, which additionally contains a second a driven sprocket mounted symmetrically to the first relative to the leading sprocket, and the chain enclosing them is made of three rows.

An additional driven sprocket and the use of a three-row chain eliminates bending moment and, as a result, avoids misalignment of the hinge rollers, which makes it possible to achieve uniform wear of the sprocket teeth and increase the traction ability of the gear with a small center distance.

The drawing shows a chain transmission with a small center distance.

The chain transmission consists of fixed on the shafts of the drive 1 and two identical driven sprockets 2 and 3, equipped with gear rims, and covering them with a three-row chain 4.

Power from the drive sprocket is transmitted through a three-row chain to two identical driven sprockets. Due to the fact that the chain transmission contains an additional second driven sprocket mounted symmetrically to the first relative to the leading sprocket, the forces acting in the end hinge of the leading branch are mutually balanced. As a result of this, it is possible to avoid curvature and twisting of the axis of the leading branch of the chain, distortions of the hinge rollers. This allows you to achieve uniform wear of the teeth of the sprockets, increase traction ability, increase transmission efficiency with a small center distance.

Information sources

1. Ivanov M.N., Finogenov V.A. Machine parts - 7th ed., Revised. and add. - M.: Higher School, 2002. - 408 p.: Ill.

2. USSR Author's Certificate No. 630469, F 16 H 7/06, 1978.

Claims (1)

The chain transmission with a small center distance, containing the drive and driven sprockets mounted on the shafts, equipped with gear rims, and covering the chain, the sprockets are shifted relative to each other along the shafts, and the gear rims are installed with a gap between themselves and the chain plates, characterized in that additionally contains a second driven sprocket mounted symmetrically to the first relative to the leading sprocket, and the chain spanning them is made three-row.