GB2336347A

GB2336347A - Roller conveyor or roller conveyor section

Info

Publication number: GB2336347A
Application number: GB9907703A
Authority: GB
Inventors: Klaus Lueckerath
Original assignee: Rotzinger AG
Current assignee: Rotzinger AG
Priority date: 1998-04-15
Filing date: 1999-04-01
Publication date: 1999-10-20
Anticipated expiration: 2019-04-01
Also published as: GB2336347B; DE19912391A1; GB9907703D0

Abstract

A roller conveyor or roller conveyor section comprises a plurality of rollers 6, an electric DC motor with a drive wheel 12 situated in the drive device 7, belt deflection wheels 13 and 14 and a toothed belt 8, wherein the toothed belt is guided so that interlocking driving and braking of the rollers engaging the toothed belt are permitted. On braking of the motor, the braking force is transmitted in an interlocking manner by the toothed belt to all the rollers 6. The conveyor may consist of a plurality of roller conveyor sections , each having a separate drive device 7. The conveyor serves for arranging articles arriving in an irregular sequence and having more or less extreme weight differences without dynamic pressure so that they can subsequently be handled or further transported together, that is to say as an aligned series with constant spacing. For this purpose the roller conveyor sections are longer than the articles to be transported, and the drive devices 7 can each be controlled by a decentral control device which is additionally connected to an associated light barrier. The conveyor may include a tensioning device 16 for tensioning the toothed belt 8.

Description

1 Roller conveyor or roller conveyor section 2336347 The present invention

relates to a roller conveyor or a roller conveyor section, which conveyor or which section serves for arranging articles arriving in irregular sequence and having more or less extreme weight differences absolutely without dynamic pressure so that they can be handled or transported as a series with constant spacing.

If, for example within a manufacturing line, an apparatus which serves for processing or handling a material which is being transported suddenly fails or is not yet ready to accept the material being transported, the conveyor which is upstream in the manufacturing direction may have to be put out of operation for at least a certain time, inevitably resulting in a back-up on the conveyor.

In order on the one hand to avoid such back-ups and on the other hand to rearrange the goods pushed towards one another and possibly caused to collide by such a back-up, in such a way that they form a series with constant spacing, conveyors have already been proposed which have a plurality of roller conveyor sections which are arranged one behind the other and which in turn can be braked independently of one another, for which purpose in particular a central control device and a plurality of light barriers are provided.

These known conveyors have a substantial disadvantage in that the braking of the roller conveyor sections is insufficient since the braking means used for this purpose do not brake all rollers of a roller conveyor section or do not act equally on all rollers to be braked. Thus, the braking distance of the goods transported on these known roller conveyor sections is not only of varying length but also relatively long in the case of different weights, since the length of the roller conveyor section must be 2 adapted to the length of the goods being conveyed and to the longest run- out distance on braking, with the result that the corresponding conveyor sections must be substantially longer than the articles to be transported thereon. In addition, the known braking means are formed by hydraulically or pneumatically driven brake levers, which can be pressed against the conveyor rollers, and are provided with a relatively complicated mechanical braking apparatus, which on the one hand results in more or less constant noise pollution due to the movement of the brake levers and on the other hand is relatively expensive. Moreover, depending on the length of the roller conveyor and the goods to be transported, the known conveyors have a relatively large drive device at one of the two ends, so that roller conveyors arranged one on top of the other require a large overall height.

It is the object of the invention to propose a roller conveyor or a roller conveyor section which does not have the disadvantages described above. A conveyor formed according to the invention and consisting of a plurality of roller conveyor sections should in particular make it possible to arrange the articles transported on it absolutely without dynamic pressure so that they can be stored, transported, further handled or packed as a series with constant spacing.

Claims

This object is achieved, according to the invention, by a roller conveyor

or a roller conveyor section having the features of Claim 1.

Advantageous embodiments form the subject of the dependent Claims.

The invention also relates to a conveyor according to Claim 5.

An embodiment of the invention is described below with reference to the drawings. In the drawings, 3 Figure 1 shows a side view of a conveyor consisting of a plurality of roller conveyor sections arranged one behind the other, Figure 2 shows a section from the conveyor shown in Figure 1, on a larger scale, Figure 3 shows a schematic diagram of an individual roller conveyor section, Figure 4 shows a section along the line IV - IV of' Figure 3 and Figure 5 shows a section along the line V - V of Figure The conveyor shown in Figures 1 and 2 and denoted as a whole by 1 consists of a plurality of roller conveyor sections 2 and conveys the articles 4 transported in the direction of the arrow 3, by means of said sections, to an apparatus 5 serving for handling or storage of the conveyed material, for example a chain store serving for buffering and/or briefly storing the articles 4. Such chain stores are very well known to a person skilled in the art. They are arranged, for example, between two processing devices handling the conveyed material and serve, inter alia, for maintaining operation of the total production line at least for a certain time in the event of a temporary failure of a processing device.

As shown in Figure 2, each roller conveyor section 2 has a plurality of conveyor rollers 6 which are arranged one behind the other and which are driven together by means of a separate drive device 7. For this purpose, the latter has a continuous toothed belt 8 which engages the conveyor rollers 6 and is driven by an electric motor.

The essential features of the invention are to be described in more detail below with reference to Figures 3, 4 and 5.

The toothed belt 8 is arranged in a frame 9 of the roller conveyor section 2. It is driven over the drive drum 4 of a DC motor 10 in such a way that it revolves in the direction of the arrow 11 during operation of the roller conveyor 1. Thus, the toothed belt 8 leads from the drive wheel 12 over a first deflection wheel 13 to a second deflection wheel 14 and from there over a tensioning device 16 formed by three wheels 15a, 15b and 15c back to the drive drum of the wheel 12.

The deflection wheels 12, 13, 14 and 15 are fixed in the frame 9. Of these, the wheels 12 and 15a are in the form of gear wheels. According to the invention, the toothed belt 8 engages the conveyor rollers 6 belonging to the roller conveyor section 2. For this purpose, each roller 6 has, at its end visible in Figure 3, radially arranged indentations 17 fitting the toothed belt 8, and furthermore a support wheel 18 belonging to each roller 6 is provided, which support wheel guides the toothed belt 8 to the corresponding conveyor roller 6 so that the toothed belt 8 engages the indentations 1.

Within the scope of the invention, 8 can of course also be supported at further rollers or similar aids which are not shown.

As is evident from Figures 1 and 2 placed on the conveyor 1 can be arranged one without dynamic pressure when the individual the toothed belt points by the articles 4 behind the other roller conveyor sections 2 are driven independently of one another and, if necessary, are either braked or even put out of operation. For this arrangement in series, in particular the roller conveyor sections 2 are longer than the articles 4 to be transported, and the drive devices -7 of the roller conveyor sections 2 are each controllable by a decentral control device which is additionally provided with an associated light barrier.

During "normal operation" of the conveyor 1 described above, all roller conveyor sections 2 are driven by the associated toothed belts 8. In contrast, the conveyor 1 operates as follows in the event of a failure or when the processing device 5 connected to the roller conveyor is in the "not ready" state:

As soon as the first article enters the region of the light barrier which belongs to the last roller conveyor section and is not shown, the motor 10 of the last roller conveyor section is switched off and the article 4 is thus braked and stopped so that it comes to a stop before the device 5. According to the invention, this braking or stopping process is distinguished by the fact that the braking force generated by switching off or short-circuiting the motor 10 is transmitted by the toothed belt 8 in an interlocking manner to all conveyor rollers 6 engaging the belt 8.

are also articles distance the case, Otherwise running section long as Whether the roller conveyor sections 2 further back simultaneously braked depends on whether the transported by them are a predetermined constant from the front article already stopped. If this is such a roller conveyor section is also braked. the roller conveyor sections further back continue individually, independently of the roller conveyor or sections already braked or stopped, and do so as the articles transported by these roller conveyor sections approach the already stopped articles without interruption and are preferably a constant distance away.

As a result of the section-by-section braking and stopping, the articles of a group can be stored, transported, handled or packed as a closed series with constant spacing.

Compared with the known devices for section-bysection braking and stopping of articles transported on conveyors, the solution according to the invention permits absolutely uniform interlocking braking acting simultaneously on all conveyor rollers of the roller conveyor section, permitting relatively rapid braking with the same braking distance even in the case of extremely different weights of 6 the articles. In turn, a consequence of this rapid braking is that the length of the individual roller conveyor sections is adapted to the longest article to be transported and need be only a small amount larger than it. In contrast to the operation of the conveyors mentioned at the outset, the running and braking of the roller conveyor sections 2 according to the invention, which are effected by the toothed belt 8, take place silently, and, owing to the relatively small amount of space required, the present solution opens up optimal possibilities for adaptation to the available space of the companies which require such conveyors. This is particularly the case because the roller conveyor sections according to the invention have no hydraulically or pneumatically movable braking means arranged underneath the conveyor rollers and manage with relatively small DC motors so that even roller conveyors arranged one on top of the other require only a small overall height.

It should be pointed out once again here that the conveyor described with reference to Figures 1 to 5 represents only one choice from various embodiments of the invention and can be modified and supplemented in various respects.

Thus, depending on their length and on the material to be transported, the individual roller conveyor sections may also have a plurality of DC motors which are connected in series and then together drive the toothed belt.

7 CLAIMS 1. Roller conveyor or roller conveyor section having a plurality of conveyor rollers (6) serving for transporting articles (4) and means for driving the conveyor rollers (6), characterized in that, at one end, the conveyor rollers (6) engage a continuous toothed belt (8) which is guided around two- deflection wheels (13, 14) arranged at the two ends of the roller conveyor or of the roller conveyor section (2), and that the drive means are formed by an electric DC motor (10) around whose drive wheel (12) the toothed belt (8) is guided so that interlocking driving and braking of the conveyor rollers (6) engaging the toothed belt (8) are thereby permitted.
2. Roller conveyor or roller conveyor section' according to Claim 1, characterized in that the conveyor rollers (6) are provided, at one of their ends, with radially arranged indentations (17) which the toothed belt (8) engages.
3. Roller conveyor or roller conveyor section according to Claim 1 or 2, characterized in that it has a tensioning device (16) for tensioning the toothed belt (8)
4. Roller conveyor or roller conveyor section according to any of Claims 1 to 3, characterized in that it has a light barrier switchable by the arriving articles and that said light barrier and the drive device are connected to a control device.
5. Conveyor, characterized by at least two roller conveyor sections according to any of Claims 1 to 4.
6. Roller conveyor or roller conveyor section substantially as hereinbefore described with reference to the accompanying drawings.