GB2214605A

GB2214605A - Gearing system for conveying drive between shafts crossing one another

Info

Publication number: GB2214605A
Application number: GB8801228A
Authority: GB
Inventors: Michael Gerald Ladell; Geoffrey Watts
Original assignee: Xerox Corp
Current assignee: Xerox Corp
Priority date: 1988-01-20
Filing date: 1988-01-20
Publication date: 1989-09-06
Anticipated expiration: 2008-01-20
Also published as: GB8801228D0; GB2214605B

Abstract

A gearing system for transmitting drive from a first shaft (1) to a second shaft (11), each shaft carrying at its end a gear wheel (2, 12). The gear wheels comprise wheels having radially extending teeth or pegs (7, 17) so shaped and spaced from one another that they mesh when the shafts cross over one another so as to transmit the drive with the gear centres misaligned. Each shaft may carry an auger flight (5, 15), whereby two augers at, say right angles to one another may transmit both material being conveyed and rotational drive around a corner. <IMAGE>

Description

Coaaed Drive Svstem This invention relates to a cogged drive system for transmitting drive from a first shaft to a second shaft, each shaft carrying a cog wheel.

One known way of transmitting drive between two shafts at right angles to one another is to use bevel gears at the end of each shaft. In certain situations, it is desirable to have the shafts crossing over each other, and simple bevel gears are then no longer suitable, because when the shafts cross over one another the gear centres are misaligned. Although gearing systems can be devised to enable drive to the transmitted from one of the overlapping shafts to the other, these systems are relatively complex and therefore expensive, and require several components other than two gear wheels and two shafts.One situation in which it is useful to have overlapping shafts is in a conveying system for particulate material using augers, such as in a xerographic system when it is required to have developer material moved by a first auger, and then by a second auger inclined, for example at a right angle, to the first. It is convenient to have the shafts overlapping at their ends to maximise transfer of developer material from the first direction to the second, and to have an arrangement for transmitting the drive simply and inexpensively outside the corner formed by the overlapping shafts.

The present invention is intended to provide such an arrangement, and provides a cogged drive system of the kind specified which is characterised in that the cog wheels comprise wheels having radially extending pegs so shaped and spaced from one another that they mesh when the axes of the shafts cross over one another so as to transmit the drive with the gear centres misaligned.

The cog wheels are preferably moulded integrally with their shafts, which may be the shafts of augers.

Thus it is possible, with two simple moulded components as the only moving parts, to provide an auger which transmits both its drive and the material which it is conveying, through a right angle. This is a very inexpensive arrangement, and is ideal for the reclaiming and transporting system of a xerograpbic cassette which reuses cleaned off toner particles, especially when the cassette is intended to be disposable.

A cogged drive system in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure lisa plan view of the cogged drive system applied to a pair of augers, Figure 2 is an elevational view of the cogged drive system of Figure 1 and Figure 3 is a plan view of part of the system shown in Figure 1, with the augers incorporated into a portion of a xerographic cassette.

Referring to Figures 1 and 2, a first shaft 1 carries at one end a cogged wheel 2, a bearing surface 3, and spaced seal retaining discs 4. The shaft 1 also carries a helical auger flight 5. The cogged wheel 2 carries near its perimeter a drive peg 6 by means of which the cogged wheel 2 and hence the shaft 1 may be rotated so that the auger flight 5 can act as a conveyor of particulate material. All the described parts 1 to 6 are preferably formed as an integral mouiding for example of plastics material, but may be constructed of any appropriate number of parts and of any suitable material.

A second shaft 11 is arranged to cross over shaft 1 near the ends of both shafts, and the second shaft 11 also carries at its end a cogged wheel 12, a bearing surface 13, and spaced seal retaining discs 14. The cogged wheel 12 is substantially the same as cogged wheel 2, and they are arranged so that the pegs or teeth 7 of wheel 2 mesh with the pegs or teeth 17 of wheel 12. The teeth are so sized and spaced that they provide driving engagement between the shafts despite the misalignment of the gear centres (clearly visible in Figure 2) due to the overlapping of the shafts. The overlapping configuration of the shafts means that the axes of the shafts (and of the cogged wheels) are non-coplanar.

Although the shafts are shown in the drawings crossing over one another at a right angle, the drive system of the invention will operate when the axes of the shafts make an angle other than a right angle. The usable range of angles is likely to be limited by the sizes of the cog wheels and the proximity of other, neighbouring, parts of the equipment in which the invention is used. Also, although the cog wheels are shown as being of approximately the same size, they can be of different sizes and have different numbers of teeth if gear ratios other than 1:1 are required.

In Figure 3, the augers are shown in a xerographic cassette for conveying toner material around a corner, as indicated by the arrows, the toner material being conveyed by auger flights 15 and 5 along the curved channel 21. The lower portion 22 and the upper portion (not shown) of the cassette provide bearing surfaces for the shafts 1 and 11, as well as defining the walls of the channel 21. Also formed in the cassette housing are retaining members for seals 23 and 24 to prevent toner material escaping on rotation of the shafts 1 and 11.

Claims

Claims:

1. Cogged drive system for transmitting drive from a first shaft to a second shaft, each shaft carrying a cog wheel, characterised in that the cog wheels comprise wheels having radially extending pegs so shaped and spaced from one another that they mesh when the axes of the shafts cross over one another so as to transmit the drive with the gear centres misaligned.

2. The drive system of claim 1 wherein each cog wheel is formed integrally with its shaft.

3. The drive system of claim 1 or claim 2, wherein each shaft carries an auger flight.

4. The drive system of any one of claims 1 to 3 wherein each cog wheel is at the end of its shaft, the cog wheels being outside the corner formed by the overlapping shafts.

5. The drive system of any one of claims 1 to 4 wherein the axes of the shafts are substantially at right angles to one another.