GB2355508A

GB2355508A - A chain

Info

Publication number: GB2355508A
Application number: GB9925026A
Authority: GB
Inventors: David Neal
Original assignee: Renold PLC
Current assignee: Renold PLC
Priority date: 1999-10-23
Filing date: 1999-10-23
Publication date: 2001-04-25
Also published as: GB9925026D0

Abstract

A chain comprises a plurality of chain links interconnected by pins so as to permit articulation of the links relative to one another. The links comprise inner and outer link plates. Each outer link plate 1 has an integral pin 3 that is releasably received in an aperture of an opposed outer link portion by a snap-connection. The pin passes through apertures 4 in opposed inner link plates 2 each of which has an inwardly extending integral boss 6 defined around each aperture. Opposed bosses are coaxially aligned relative to one another and to the pin on which they are rotatably disposed with the inner link plates. The chain is cheap to manufacture and simple to assemble. In a modified embodiment, the chain comprises single pairs of opposed, cranked link plates with the first end of each link (an inner link portion) being received between the second ends (outer link portions) of an adjacent pair of plates. The link plates are moulded from a polymer, and have brackets 8,9 for connection to other components for transportation purposes.

Description

2355508 A CHAIN The present invention relates to a chain of the kind used

for transmission and/or transportation.

A conventional roller and bush chain used for transmission or transportation purposes has pairs of opposed inner link plates that are interconnected with opposed pairs of outer link plates by pins about which the inner link plates articulate. Each pin is fixed at each end to an outer link plate but is pivotal relative to the inner link plates within a bush that extends between opposed apertures in the inner link plates. A roller is rotatably disposed on each bush.

Such chains have been manufactured and sold for years without significant development. However, there is an increasing demand for such chains to be constructed in such a way that they are cheaper to manufacture and assemble.

It is an object of the present invention to provide for a chain that is relatively cheap to manufacture and simple to assemble.

According to the present invention there is provided a chain comprising a plurality of chain links interconnected by pins so as to permit articulation of the links relative to one another, the links comprising opposed outer link portions that are releasably connected by at least one pin and inner link portions each having an integral boss, the pin being received by both bosses such that they are substantially co-axial and are rotatable with the inner link portions relative to the pin.

The link portions preferably comprise two outer link plates and two inner link plates. Each inner link plate preferably has a pair of apertures from which bosses extend inwardly of the chain, the bosses of opposed apertures being substantially coaxially aligned with one another on said pin.

The pin may be integral with one of the opposed outer link portions or plates and snap-connectable with other.

Specific embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure I is an exploded perspective view of a chain of the present invention, shown with alternative outer link embodiments.

2 Referring now to figure I of the drawings, the exemplary chain has opposed pairs of spaced outer link plates 1 (two alternative designs la, lb are shown in the foreground) and opposed pairs of inner link plates 2.

Each outer link plate I has an integral pin 3 that extends towards the opposed outer link plate I and passes through apertures 4 in the opposed inner link plates 2 before being received in an aperture 5 of the opposed outer link plate 1 in a snap-fit connection.

Each inner link plate 2 has two spaced apertures 4, one for each pin 3 of adjacent outer link plates 1. The inwardly facing major surfaces of each inner link plate 2 have an integral circular boss 6 defined around each aperture 4. When the chain is assembled opposed bosses 6 are received on a common outer link pin 3 such that they are substantially coaxia:l to one another and to the pin 3 and are rotatable together relative to the pin 3. In effect, the bosses 6 combine to replace the roller of a standard bush roller chain, although in this design the roller is split into two halves, each half being integral with a respective inner link plate. The split roller arrangement lends itself to accurate manufacture by polymer moulding.

The outwardly facing surface of the inner link plate 2 may have a raised formation 7 that is complementary to the outside contour of the outer link plate I so as to provide a guide surface during assembly and provide a bearing surface during operation of the chain.

The chain of the present invention may be provided with outer link plates of different configurations according to the application in which it is to be used. For example the outer link plates I a, I b shown to the left and right in the foreground of figure I each have a connecting plate 8, 9 by which the chain may be connected to other components for transportation purposes as is well known.

For any given application the chain arrangement has inner link plates of identical configuration and identical outer link plate designs and as such is relative cheap to manufacture particularly if it is mass produced from a suitable moulded polymer. Moreover, since the pin is integral with the outer link plate and the roller comprises bosses 6 that are each integral with the inner link plate 2 the chain has few 3 components thereby making it simple to assemble. The snap-connection between the pin 3 and the outer link plates 1 also provides for ease of assembly.

It will be appreciated that numerous modifications to the above-described design may be made without departing from the scope of the invention as defined in the appended claims. For example, the chain may comprise single pairs of opposed link plates, with each link plate being cranked so as to define a first end (at which the opposed link plates spaced apart by a relatively short distance) and a second end (at which the opposed link plates are spaced apart by a greater distance than that at the first end. The first end of each link defines an inner link portion that is received between the second end (the outer link portion) of an adjacent pair of plates.

4

Claims

1. A chain comprising a plurality of chain links interconnected by pins so as to permit articulation of the links relative to one another, the links comprising opposed outer link portions that are releasably connected by at least one pin and inner link portions each having an integral boss, the pin being substantially coaxially received by said boss and the boss being rotatable with the inner link portions relative to the pin.

2. A chain according to claim 1, wherein the outer link portions comprise two outer link plates and the inner link portions comprise two inner link plates.

3. A chain according to claim 2, wherein each inner link plate has a pair of apertures from each of which a said boss extends inwardly of the chain, the bosses of opposed apertures being substantially coaxially aligned with one another on said pin.

4. A chain according to any preceding claim, wherein the pin is integral with the one of the opposed outer link portions and is snap-connectable with other.

5. A chain according to any preceding claim, wherein the outer link plates have support brackets for connection to transportation components.

6. A chain substantially as hereinbefore described with reference to the accompanying drawings.