WO2021123079A1

WO2021123079A1 - Method and device for conveying products

Info

Publication number: WO2021123079A1
Application number: PCT/EP2020/086907
Authority: WO
Inventors: Baptiste BALTZ
Original assignee: Sidel Participations
Priority date: 2019-12-19
Filing date: 2020-12-17
Publication date: 2021-06-24
Also published as: FR3105197B1; FR3105197A1

Abstract

The present invention relates to a method for conveying products (1) from an upstream workstation (2) to a downstream workstation (4), in which method a first conveyor (5) is fed with a single-files stream of products (1) and transports them at a determined speed to a second conveyor (6), said products (1) passing directly between the conveyors (5, 6); a target spacing between the products (1) on the second conveyor (6) is determined; then at a first point (50) on the first conveyor (5) the presence of said products (1) is detected and a first interval (7) between two given successive products (10, 11) is determined, and a comparison is made between said first interval (7) and the target spacing, then, as said given products (10, 11) pass on to the second conveyor (6), the speed thereof is controlled according to said comparison, then at a second point (51) downstream of said first conveyor (5), a second means (501) for detecting the presence of said products (1), said means (12) calculating second intervals (8) between the products (1) according to the information collected by said second detection means (501), said control means (13) adjusting the speed of the second conveyor (6) according to said second intervals (8). The invention also relates to a corresponding conveying device (2).

Description

DESCRIPTION

The present invention falls within the field of conveying products within an industrial line.

For the purposes of the present invention, the term “product” encompasses an individual object or several objects grouped together, in particular in the form of a lot or bundle. Such a product is a container, such as a bottle or a flask, or even a brick or a can. A product can be made of any type of material, in particular plastic, metal or even glass. A product can be rigid or semi-rigid.

Such a container is intended to contain, in a non-exhaustive manner, a fluid, a liquid, powders or granules, in particular of the agri-food or cosmetic type, or dedicated to maintenance or personal hygiene.

In the context of the invention, a product can have any type of shape, symmetrical or not, regular or irregular.

In a known manner, within an industrial line, the products can receive several different successive treatments, ranging from the manufacture of the container by a forming operation to the packaging in batches of several grouped products, including filling. At the end of these treatments, the products are said to be "finished".

During these different stages, the products are transported in a direction of travel, from upstream to downstream, between different stations dedicated to each treatment that the products must undergo. Such transport is carried out by means of a conveying device.

Such a conveying device is provided with at least one conveyor with a movable surface, on the upper face of which the products rest on their bottom. For example, a conveyor can be of the endless belt type. The movement of said mobile surface then ensures the conveying of products from an upstream station to a downstream station.

More specifically, an upstream station can feed the conveying device at the input according to a single-line flow of products, namely one by one following one another on a line. Due to the production rate linked to this upstream station, the conveying device must maintain a fixed transport speed, proportional to the flow rate of products supplied by said upstream station. By way of example, an upstream station can be a filler, carrying out a unit treatment of each product, which it delivers in a continuous flow at regular intervals.

Similarly, the downstream station is supplied according to said flow of products transported by the conveying device, or even possibly with several flows of combined products. This downstream station has its own operating rate, depending in particular the number of products it must process simultaneously. Consequently, it is necessary to synchronize the upstream and downstream stations with one another, as well as the transport speed of the conveying device, in order to maintain a continuous supply of products to said downstream station. Generally, within an industrial line, it is the station with the lowest rate which imposes its rhythm on the other stations of the line. By way of example, a downstream station can be a labeling machine successively treating each of the products, or else a wrapping machine intended to coat and hold a batch of several grouped products.

In order to improve the flexibility in the operation of a production line, intermediate stations make it possible to accumulate a quantity of products, between an upstream station and a downstream station. Such a station makes it possible to manage speeds that are momentarily different from one machine to another, to limit the loss of productivity linked to a momentary malfunction of an upstream or downstream station and to allow emptying of the upstream station. For example, accumulation stations make it possible to build up a reserve of products and ensure a continuous supply of said downstream station for a period of time, even in the event of a malfunction or slowdown of an upstream station, or even time of emptying a machine.

A recurring problem arises when the flow delivered by the upstream station becomes irregular, for example due to a non-conforming or defective product which has been extracted from the flow. The same applies if the interval between the products is no longer regular on leaving the upstream station, in particular due to a slowing down, for example in the event of an operator intervening. Consequently, the regularity of the flow is modified, in particular on an ad hoc basis, namely that the regular interval between a product and the preceding product and / or the following product is not respected.

An existing solution consists in positioning a means ensuring the setting in pitch of the products, generally in the form of a rotating element, such as a worm. However, such a rotary element is dimensioned and with a speed configured as a function of a given product format and of the pitch to be obtained. It is therefore necessary to change it and configure it each time the production format changes.

In particular, upstream of the rotary element, it is necessary to accumulate the products, which come into contact with one another, in touch-to-touch, which is liable to generate pressure between them, or even to deform them.

It was therefore imagined to do without this rotating element and to act when the products pass to a downstream conveyor, with a view to compensating for a non-conforming spacing of certain products.

A known solution consists in detecting a large spacing between two products, greater than the desired interval. When passing the products to the downstream conveyor, we then stops the second conveyor, for a given period, until the spacing is reduced between the stopped downstream product and the upstream product still in motion, until the desired interval is reached. The downstream conveyor is then restarted until its transport speed is again reached.

While such a solution makes it possible to roughly reduce a spacing between the products, it is limited to a spacing of significant length, corresponding to several products.

In addition, when restarting, the time required to return to the nominal speed of the downstream conveyor can induce a rapprochement between the upstream product which has arrived on the second conveyor with respect to the following product, modifying an interval that should still be compensated for. .

In addition, it is not possible to increase the interval between two products which are too close.

In a related manner, such a solution resulting in a sudden stop, also generates imbalances, or even falls of products.

Other solutions are known, in particular from documents DE 20 2011 109327 U1, US 2001/035332 or EP 0 433 231, consisting in modifying the speed of a conveyor located downstream, with respect to the detection of an interval between products transported by a conveyor located upstream.

The object of the invention is to overcome the drawbacks of the state of the art by proposing a conveying method provided with a first conveyor at determined speed followed by a second conveyor at variable speed in which the speed of the second conveyor is adapted. according to the intervals measured between the products on this first conveyor in order to compensate for potential irregularities between the products at the level of the first conveyor.

In addition, the invention provides for adding an additional detection at the level of the first conveyor and downstream, in order to verify any movement between products likely to have occurred along the first conveyor and, therefore, to detect in a more refined manner. a possible variation in the interval between said products, resulting in particular from the size of one of the conveyors or from the sliding of the products on one of the conveyors.

With a second detection downstream, in particular as close as possible to the entrance of the downstream conveyor, it is also possible to adjust the speed of said downstream conveyor as closely as possible.

Thus, the invention makes it possible to rectify, even very slightly, the spacing between the products from the upstream station to the downstream station so that the latter is regular and corresponds to a given value. In particular, the invention makes it possible to reduce but also to increase the pitch of the upstream station to coincide with a different desired pitch at the level of the downstream station. The invention therefore makes it possible to increase the precision of the compensation for any fluctuation intervals between the products, with reactivity, in particular avoiding any risk of jamming along one of the conveyors.

To do this, the invention relates first of all to a method of conveying products from an upstream station to a downstream station, in which:

- A first conveyor is fed from said upstream station with a single-line flow of products;

- The first conveyor transports said flow at a determined speed to a second conveyor;

- Said products pass directly from the first conveyor to the second conveyor which delivers said products to the downstream station;

- A target pitch is determined between the products on the second conveyor.

Such a conveying method further comprises at least the following consecutive steps:

- at a first location of the first conveyor, the presence of said products is detected;

- A first interval is determined between two given successive products;

- A comparison is made between said first interval and the target pitch;

- During the passage of said given products at the second conveyor, the speed of said second conveyor is controlled as a function of said comparison.

Such a conveying method is characterized in that it further comprises the following steps:

- The presence of said products is detected at a second location of said first conveyor downstream of said first location;

- Second intervals between the products are determined;

- The speed control of said second conveyor is adjusted as a function of said second intervals.

In addition, said aforementioned steps are reproduced for all the products of said stream. According to additional, non-limiting characteristics, such a conveying method can further comprise a step of comparison between the first intervals and the second intervals; the adjustment step being carried out as a function of said comparison between the first intervals and the second intervals.

Said conveying method may further comprise a step of determining an average of said second intervals over a section of said flow; the adjustment step being carried out as a function of said average of said second intervals.

Said conveying method may further comprise the following steps:

- The presence of said products is detected at a third location at the inlet of said second conveyor;

- Third intervals are determined between the products;

- The speed control of said second conveyor is adapted as a function of said third intervals.

Said conveying method may further comprise a step of comparing the third intervals and the target pitch; the adaptation step being carried out as a function of said comparison between the third intervals and the target pitch.

Said conveying method may further comprise a step of determining an average of said third intervals over a section of said flow; the adaptation step being carried out as a function of said average of said third intervals.

If a hole is detected between two products, the second conveyor can be decelerated until the said two products are brought together; then the second conveyor can be accelerated to the speed of said first conveyor.

The products can be delivered by the second conveyor to an accumulation surface as a downstream station.

The step of detecting the presence of said products can be carried out continuously. Thus, by modulating the speed control of the second conveyor, it is possible to decelerate or accelerate a part of the conveying surface.

The invention also relates to a device for conveying products from an upstream station to a downstream station, comprising at least:

a first conveyor circulating at a determined speed and supplied with a single-line flow of products by said upstream station;

a second conveyor located directly downstream of said first conveyor and delivering said products to said downstream station;

a target pitch being determined between the products on the second conveyor.

Such a conveying device further comprising:

- at a first location of said first conveyor, a first means of detecting the presence of said products;

a means for calculating first intervals between the successive products, as a function of the information collected by said first detection means;

- Means for controlling the speed of said second conveyor, as a function of said first intervals with respect to said target pitch.

Said conveying device is characterized in that it comprises

- at a second location of said first conveyor and located downstream of said first location, a second means for detecting the presence of said products;

said calculation means ensuring the calculation of second intervals between the products of said first conveyor, as a function of the information collected by said second detection means;

- said control means ensuring the adjustment of the speed of the second conveyor by function of said second intervals.

According to additional, non-limiting characteristics, the first conveyor and / or the second conveyor can be of the endless belt type.

Said conveying device may comprise:

- at a third location at the inlet of said second conveyor, a third means for detecting the presence of said products;

said calculation means ensuring the calculation of third intervals between the products of said second conveyor, as a function of the information collected by said third detection means;

- Said control means ensuring the adjustment of the speed of the second conveyor as a function of said third intervals.

Said first and / or second and / or third product detection means may comprise at least one continuous type sensor.

Other characteristics and advantages of the invention will emerge from the detailed description which will follow of non-limiting embodiments of the invention, with reference to the appended figures, in which:

FIG. 1 schematically represents a simplified elevation view of an exemplary configuration of a device for conveying a regular and compact flow of products, along a first and a second jointed conveyor, showing in particular at the inlet the first conveyor detecting within the flow of products a vacuum originating from a missing product, while the first conveyor and the second conveyor are traveling at the same speed;

- Figure 2 schematically shows a view similar to Figure 1, showing in particular a deceleration of the second conveyor, to fill said void in the flow of products when the products concerned pass from the first conveyor to the second conveyor;

- Figure 3 schematically shows a view similar to Figure 2, showing in particular a return to normal of the regular circulation of products along the first and second conveyors at identical speeds;

- Figure 4 shows schematically a simplified elevational view of another example of configuration of a device for conveying a regular and spaced flow of products, along a first and a second joint conveyors, showing in particular at the inlet of the first conveyor, the detection of a restricted interval between two given successive products, as well as a detection upstream of the outlet of said first conveyor; FIG. 5 schematically represents a view similar to FIG. 4, showing in particular an acceleration of the second conveyor, to increase said interval restricted at the time of passage of said successive given products from the first to the second conveyor;

FIG. 6 schematically represents a view similar to FIG. 5, showing in particular a return to normal with identical speeds of the first and second conveyors;

- Figure 7 shows schematically a simplified elevational view of another example of configuration of a device for conveying a regular and spaced flow of products, along a first conveyor and a second conveyor whose ends are adjacent, with a guide of the products as they pass from one of said conveyors to the other, showing in particular at the input of the first conveyor the detection of a first interval between the successive products of the product flow, a detection close to the exit from said first conveyor of a second interval, as well as a detection at the entrance of the second conveyor of a third interval; and

- Figure 8 schematically shows a view similar to Figure 7, showing in particular a slowing down of the second conveyor in order to reduce the pitch between the products of the flow.

The present invention relates to the conveying of products 1 within an industrial line.

For the purposes of the present invention, the term “product” encompasses an individual object or several objects grouped together, in particular in the form of a lot or bundle. Such a product 1 is a container, such as a bottle or a flask, or else a brick or a can. A product 1 can be made of any type of material, in particular plastic, metal or even glass. A product 1 can be rigid or semi-rigid.

In the context of the invention, a product 1 can have any type of shape, symmetrical or not, regular or irregular.

In a known manner, within an industrial line, the products 1 can receive several different successive treatments, ranging from the manufacture of the container by a forming operation to the packaging in batches of several products 1 grouped together, including through the filling. At the end of these treatments, the products 1 are said to be "finished".

During these different stages, the products 1 are transported in a direction of movement, longitudinal or essentially longitudinal, from upstream to downstream, between different stations dedicated to each treatment that the products 1 must undergo. Such transport is carried out by means of a conveying device 2.

Further on, such a conveying device 2 ensures the movement of the products 1 from a station 3 upstream to a station 4 downstream.

It will be noted that the upstream station 3 can be of any type, such as a product processing station 1, in particular a filler, such as a conveyor, or even as a product accumulation surface 1. Likewise, the downstream station 4 can be of any type, such as a packaging station, in particular a shrinkwrapper or a case packer, such as a conveyor, or even as an accumulation surface.

In the context of the present invention, the products 1 are conveyed in the form of a single-line flow, namely that the products 1 are moved one after the other, in a single row extending in the direction of shifting.

Within such a single-line flow, the products 1 can be placed side by side with each other as a “key-key” or else spaced at an interval depending on the operation of a machine located upstream, in particular by the upstream station 3.

In this context, the conveying device 2 comprises a first conveyor 5 circulating at a determined speed and supplied with a single-line flow of products 1 by the upstream station 3. The upstream station 3 can directly supply the first conveyor 5 with products 1 or via an intermediate conveyor.

The conveying device 2 also comprises a second conveyor 6, delivering said products 1 to a downstream station 4. Similarly, the second conveyor 6 can deliver the products 1 directly to a downstream station 4 or else via a other conveyor. It will be noted that the first conveyor 5 and / or the second conveyor 6 can be composed of a single conveyor or of a succession of several conveyors.

In addition, the first and second conveyor 5,6 can be of any type. They can be band, with a rotating member such as a carousel or a star, or even an endless screw, or even grippers, such as tulips.

According to a preferred embodiment, the first conveyor 5 and / or the second conveyor 6 are of the endless belt type.

In addition, the second conveyor 6 is located directly downstream of said first conveyor 5. In other words, the downstream end of the first conveyor 5 opens towards the upstream end of the second conveyor 6. The products 1 therefore pass from the outlet. from the first conveyor 5 to the entrance of the second conveyor 6, without processing or intermediate conveyor, nor any assisted transfer in particular assisted by dedicated means.

According to the embodiments shown in Figures 1 to 6, the first and second conveyors 5.6 are butted, in the extension of one another.

According to the embodiment shown in Figures 7 and 8, the downstream end of the first conveyor 5 is adjacent to the upstream end of the second conveyor 6, the products 1 being guided transversely from one to the other of said conveyors 5 , 6. In addition, between the conveyors 5, 6, the junction can comprise a transfer zone, in particular by sliding the products 1 on a sheet called “dead plate”. Advantageously, the invention provides for regulation of the conveying from the first conveyor 5 to the second conveyor 6, in order to ensure that the flow of products 1 is regular.

It will be noted that the regularity of a flow corresponds to an identical or substantially identical spacing between the products. A regular flow may correspond to products circulating at a given pitch, depending in particular on the supply by the downstream station 3. As such, a target pitch is determined between products on the second conveyor 6 comprises a target pitch. This target step corresponds to a fixed and identical interval between the products which follow each other directly within the product flow. By way of example, the products 1 must be spaced at regular intervals, or alternatively placed side by side.

In addition, this target pitch of the second conveyor 6 is a “targeted” value, which it is desired to achieve, namely that it is envisaged and must be respected, such as an instruction, in order to ensure the optimum operation of the station. 4 downstream.

In order to obtain this target pitch, first of all, the invention relates to a method for conveying products 1 from the upstream station 3 to the downstream station 4.

Such a conveying method comprises, without limitation, several successive steps. As mentioned above, the first conveyor 5 is supplied from said upstream station 3 with a single-line flow of products 1. The first conveyor 5 transports said flow to the second conveyor 6. Finally, said products 1 pass from the first conveyor 5 to the second conveyor 6 which delivers said products 1 to the downstream station 4.

In addition, the passage from the first conveyor 5 to the second conveyor 6 takes place directly, namely that no treatment or conveyor takes place when the products 1 pass between the conveyors 5,6.

It will be noted that the transport by the first conveyor 5 takes place at a determined speed, namely that the speed of said first conveyor 5 is dependent on the feed speed, in particular the speed at which the products 1 are processed or sent by the post. 3 upstream. In short, the operation of the first conveyor 5 is synchronized with the operation of the upstream station 3.

In addition, the speed of the first conveyor 5 can be adjusted or directly subjected in a proportional manner to said upstream station 3. By way of example, when launching a production of a format of products 1, the flow rate of products 1 at the outlet of the upstream station 3 increases gradually, until an optimum rate is reached; consequently, the speed of the first conveyor 5 increases synchronously, in order to follow the variation in the flow rate of the upstream station 3. In short, we do not act voluntarily on the control of the speed of the first conveyor 5.

A target pitch is determined between the products 1 on the second conveyor 6. This pitch therefore corresponds to the expected spacings between the products 1 of the flow which are located on the second conveyor 6. This target pitch is therefore a regular interval between the products 1, that one wishes to obtain when the products 1 circulate on the second conveyor 6. Such a target pitch is determined with a view to correctly supplying the downstream station 4, according to its rate of processing of the products 1 that it receives. The target pitch therefore corresponds to the theoretical pitch between the products 1 on the second conveyor 6, namely the interval between them.

It will be noted that an interval corresponds to the distance between two products 1, namely the length separating, on the one hand, the upstream end of a product 1 and, on the other hand, the downstream end of a product 1 which follows it directly. In short, it is the distance between the ends of two successive products 1. In such an interval, there is therefore no product. Advantageously, the conveying method provides, at a first location 50 of the first conveyor 5, to detect the presence of the products 1. In short, on the first conveyor 5, the presence of all the products 1 is detected. In other words, each of said products 1 is detected as they pass through said first location 50. As a result, the absence of product 1 is also detected at this first location 50, namely the free space between two successive products 1.

As such, two successive products 1 follow each other directly, one after the other, with only a space between the two or not, if they are in touch-key.

Consequently, it is possible to determine a first interval 7 between two given successive products 10,11. For purposes of simplification, in the remainder of the text, two successive products 10,11 may be called a pair or pair of products 1. In particular, a first interval 7 is determined between all the pairs or all the pairs of products 1 transported by the first conveyor 5, when the products 1 pass at said first location 50. Thus, the spacing between all the products 1 located downstream after detection and circulating on the first conveyor 5 from the first location 50 is known.

In short, the invention makes it possible to determine, from the first location 50, a virtual model corresponding to the actual size of products 1 of the first conveyor 5 and its movement, like a kind of dynamic photograph. As the speed of the first conveyor 5 is known, this model makes it possible to know at any time, after detection, which portions of the first conveyor 5 are free and those occupied by the products 1. In addition, the invention provides for recording the first intervals 7 between all the products 1 detected, in particular through a register. Such a register can be of the software type, executed on a suitable computer terminal. In particular, said register can be a queue of “FIFO” type (for “First In First Out”). Said register therefore manages in an orderly manner the successive recordings of the first intervals 7 at the first location 50 until the reading of these records at the exit of the first conveyor 5. The management of said register is therefore synchronized with the characteristics of the first conveyor 5, in particular its length and its speed. shifting.

Then, the invention provides for each pair of products 1, if their first interval 7 does not correspond to the target pitch, to act on the speed of the second conveyor 6.

To do this, during the passage of said products 10,11 given at the second conveyor 6, the speed of said second conveyor 6 is controlled as a function of said first detected interval 7 and of said target pitch. In short, a comparison is made between the first measured interval 7 and the target pitch, and the speed of the second conveyor 6 is adjusted to maintain or modify the first interval 7 which has been determined upstream for said two products 10,11, in view of obtaining the target interval on the second conveyor 6. In other words, depending on the case, one accelerates, one slows down or one maintains the speed of the second conveyor 6.

By way of example, an acceleration of the second conveyor 6 makes it possible to increase the interval between two given products 10,11, and vice versa for a deceleration. Indeed, the speed control of the second conveyor 6 is carried out, for said two given products 10,11, at the moment when the product 10 located downstream is taken over by the second conveyor 6 while the product 11 located upstream is still on the first conveyor 5, namely that the interval between them is between the first conveyor 5 and the second conveyor 6 and that the downstream product 10 is supported by said second conveyor 6. Thus, in act on the speed of the second conveyor 6, it is possible to modify the interval with the upstream product 11 which follows it.

As mentioned previously, the operation is repeated for all the products 1, namely by checking the first interval between each product 11 upstream and the downstream product 10 which precedes it. The conveying process therefore comprises at least the following steps:

- At a first location 50 of the first conveyor 5, the presence of said products 1 is detected;

- A first interval 7 is determined between two given successive products 10,11;

- A comparison is made between said first interval 7 and the target pitch;

- During the passage of said products 10,11 given at the second conveyor 6, the speed of said second conveyor 6 is controlled as a function of said comparison.

Said aforementioned steps are reproduced for all the products 1 of said flow, in order to obtain the target pitch on the second conveyor 6.

Preferably, the detection of the first interval 7 is carried out continuously. In short, the presence and absence of products 1 are detected at the level of the first location 50. More precisely, at least one sensor reacts to the presence of a product 1, as long as it passes in vis- with respect to its detection spectrum; the length of said detected product 1 is then known, but also the length where no product 1 is detected and which corresponds to the interval between two given products 10,11. In short, we obtain a profile of the presence of products 1 on the first conveyor 5.

Alternatively, the detection can be carried out sequentially, for example according to a determined regular period or at times spaced out in time, or even by detecting the start of a product and, from its known dimension, by carrying out a subsequent detection to determine the distance where no product is detected, until the start of the next product.

Such continuous or sequential detection can be carried out by suitable sensors. Preferably, the detection is carried out optically, by means of a suitable photoelectric cell.

In a related manner, the detection of the presence of a product 1 can be carried out over time, then the interval between two given products 10,11 is calculated from the elapsed time of detection between two successive products 10,11, namely the duration of detection of the absence of product 1, as a function of the known speed of the first conveyor 5.

With reference to FIGS. 1 to 3, an example of implementation of the conveying method therefore consists in detecting at the level of the first conveyor 5, the interval between the products 1, with a view to verifying the regularity of the flow and to compensate for any irregularity. between two given 10.11 products.

FIG. 1 shows a greater distance between the downstream product 10 and the upstream product 11 which directly follows it. In short, there is a gap between the products 10,11. This spacing is detected at said first location 50 as the first interval 7 between said two given products 10,11. This first interval 7 does not correspond to the desired target pitch on the second conveyor 6 and it should be compensated for.

FIG. 2 shows the slowing down of the second conveyor 6, when the products 10,11 given are located at the passage from the first conveyor 5 to the second conveyor 6. This slowing down is maintained until the length of the first interval 7 reaches that of the not target.

Then, as visible in Figure 3, the speed of the second conveyor 6 is increased again, until the speed of the first conveyor 5 is reached.

The flow of products 1 is then regular, with a pitch on the first conveyor 5 identical or substantially identical to the target pitch of the second conveyor 6.

Such an operation of regulating the conveying can be carried out several times in succession, for each first interval 7 detected between two successive products 1 and which does not correspond to the target pitch. Advantageously, the speed of said second conveyor 6 is controlled as a function of of said first interval 7 and of said target pitch.

Advantageously, the invention provides for monitoring the state of the flow at another location on the first conveyor 5, located downstream from the detection of the first interval 7.

To do this, the presence of said products 1 is detected at a second location 51 downstream from said first location 50, then second intervals 8 between said products are determined.

In particular, the second place 51 can be located near the exit of said first conveyor 5, before the end of said first conveyor 5 and the arrival on the second conveyor 6. However, the second place 51 is located at a sufficient distance of the end of the first conveyor 5, for example at a length corresponding to at least two products 1.

This length between the second location 51 and the end of the first conveyor 5 is sufficient to, where appropriate, detect a rise of the products 1 following the action taken to modify the spacing between the products 1, in particular when it is acts to reduce this spacing. In other words, in the event of slowing down of the second conveyor 6, it is possible that the products 1 approach until they accumulate, which can cause an unwanted modification of the intervals on the first conveyor 5. At worst, the rise of the products 1 can cause a jam, the products 1 sticking against each other, touching, which is liable to cause deformation by compression between them.

In order to avoid such a malfunction, the speed control of said second conveyor 6 is adjusted as a function of said second intervals 8, when said products 1 pass through said second location 51. This second check downstream from the first location 50, advantageously makes it possible to check that a second interval 8 corresponds to the first interval 7.

By way of example, if the second conveyor 6 is slowed down and that at least one second interval different from the first interval 7 is detected, then the second conveyor 6 is again accelerated. In short, a comparison is advantageously carried out between the first intervals. 7 and the second intervals 8, in particular for given successive products 10,11, and the control of the speed of the second conveyor 6 is intervened when these intervals 7,8 are different from one another.

Similarly to the detection of the first interval 7, the detection of the second intervals 8 can be carried out continuously, with similar means but dedicated to said detection of the second intervals 8.

Alternatively, the detection of the second intervals 8 can be carried out sequentially. With reference to FIGS. 4 to 6, an example of implementation of the conveying method therefore consists in detecting at the level of the first conveyor 5, the first interval 7 between products 1, with a view to verifying the regularity of the flow and to compensate for a possible irregularity between two products 10,11 given, but also downstream of the first place 50 the second intervals 8, at the level of the second place 51. In particular in the case of figure shown, the flow of products 1 has a large pitch, namely an interval between two products 1 which is greater than the dimension of a product 1, in particular its length.

FIG. 4 shows a smaller distance between the downstream product 10 and the upstream product 11. This lesser spacing is detected at said first location 50 as the first interval 7 between said two given products 10,11. This first interval 7 does not correspond to the desired target pitch on the second conveyor 6 and it should be compensated for.

Figure 5 shows the acceleration of the second conveyor 6, when said first interval 7 of the given products 10,11 is at the passage of the first conveyor 5 to the second conveyor 6. This acceleration is maintained until the length of the first interval 7 reaches that of the target step.

Then, as can be seen in FIG. 6, the speed of the second conveyor 6 is reduced again, until the speed of the first conveyor 5 is reached.

In addition, during this regulation, the second intervals 8 are constantly checked, with a view to possibly intervening on the above-mentioned adjustment of the speed of the second conveyor 6.

According to one embodiment, an average of said second intervals 8 is carried out over a section of said stream.

It will be noted that a section corresponds to a virtual division into portions or sections of the stream. A flow is therefore made up of several successive sections. The sections can have a fixed and identical length with respect to each other. Depending on the length of a section, the latter can include one but preferably several products 1, in whole or not, or even no product 1 if the section corresponds to a spacing between two products 1. The length of the sections can be dependent and adapted according to said flow. Preferably, a section comprises a length encompassing several second intervals 8, namely that it comprises at least three products 1.

From then on, the second intervals 8 are averaged over a section, with a view to comparing the result with the first interval 7.

Then, the speed control of said second conveyor 6 is adjusted as a function of said average.

This average makes it possible to fine-tune the speed of the second conveyor 6 and to check that the command possibly induced by the value of the first interval 7, applies to a first interval of the given products 10,11 which should be compared or to rule out, and do not not modify the interval between the following products 1 on the first conveyor 5. This average of the second intervals 8 on the successive sections of the flow of products 1 makes it possible to smooth the action on the second conveyor 6.

By way of example, a section can extend over a distance and the products 1 which pass over this distance are detected to determine the second intervals 8 between them. It is averaged to verify that the average spacing is consistent. Otherwise, there is an influence, in particular in a proportional manner, on the speed of the second conveyor 6 once the average of each section has been calculated.

According to one embodiment, the invention provides for monitoring the state of the flow at the level of the second conveyor 6, when the products 1 pass from the first conveyor 5 to the second conveyor 6, namely when the products pass. 1 between the first conveyor 5 and the second conveyor 6, or else just downstream in the inlet portion of the second conveyor 6.

To do this, the presence of the products 1 is detected at a third location 60 of said second conveyor 6, then third intervals 9 between said products 1 are determined.

This third location is preferably located at the inlet of the second conveyor 6. In particular, the detection is carried out at the level of the interface between the first conveyor 5 and the second conveyor 6.

Then, the speed control of the second conveyor 6 is adapted as a function of said third intervals 9, when the products 1 pass through said third place 60.

Similarly to the detection of the first interval 7, the detection of the third intervals 9 can be carried out continuously, with similar means but dedicated to said detection of said third intervals 9.

Alternatively, the detection of the third intervals 9 can be carried out sequentially. This detection of the third intervals 9 makes it possible to verify, at the time of the passage of the products 10,11 given from the first conveyor 5 to the second conveyor 6, that the action determined beforehand by the first interval 7, indeed leads to the expected result by measuring said third intervals 9. The third interval 9 must correspond to the target pitch.

A comparison is advantageously made between the third intervals 9 and the target pitch, and the control of the speed of the second conveyor 6 is intervened when the intervals 9 are different from the target pitch.

With reference to FIGS. 7 and 8, an example of implementation of the conveying method therefore consists in detecting at the level of the first conveyor 5, the first interval 7 between products 1, with a view to verifying the regularity of the flow and to compensate for a possible irregularity between two products 10,11 given, but also downstream of the first place the second intervals 8, as well as at the entrance of the second conveyor 6 by detection of the third intervals 9. In particular in these figures, the flow of products 1 has a no greater on the first conveyor 5 than the pitch between the products 1 of said flow on the second conveyor 6.

FIG. 7 shows the greater spacing of the first interval 7 detected between the downstream product 10 and the upstream product 11, with respect to the target pitch of the second conveyor 6. This first interval 7 does not correspond to the spacing between the products 1 desired on the second conveyor 6 and it should be compensated.

Figure 8 shows a deceleration of the second conveyor 6, during the passage of the products 10,11 given from the first conveyor 5 to the second conveyor 6. This deceleration is maintained until the length of the first interval 7 reaches that of the target pitch. . Then, the speed of the second conveyor 6 is accelerated again, until it reaches the speed of the first conveyor 5, to find itself in the configuration visible in FIG. 7. In short, the second conveyor 6 is controlled back and forth. comes.

The operation is repeated each time products 1 pass, in order to reduce the pitch between the products 1 from the first conveyor 5 to the second conveyor 6.

The reverse is also possible to increase the pitch from the first conveyor 5 to the second conveyor 6.

In this example, the second intervals 8 are also detected and determined, in particular in order to compare them with the first interval 7, as well as the third intervals 9, in particular in order to compare them with the target pitch.

According to one embodiment, an average of said third intervals 9 is carried out over a section of said stream.

It will be noted that a section for these third intervals 9 is similar to the previous definition of a section.

From then on, the third intervals 8 are averaged over a section, with a view to comparing the result with the target pitch.

The adjustment may consist of holding, accelerating or decelerating the predetermined speed control. In particular, when the average of the third intervals 9 corresponds to the target pitch, the speed control of the second conveyor 6 is in principle not changed. The adaptation of the command corresponds to a modification when the average is different from the target pitch.

This average makes it possible to fine-tune the speed of the second conveyor 6 and to check that the command possibly induced by the determination of the first intervals 7, but also possibly induced by the determination of the second intervals 8, makes it possible to obtain the target pitch. This average of the third intervals 9 on the successive sections of the flow of products 1 makes it possible to smooth the action on the second conveyor 6.

According to one embodiment, as can be seen in FIGS. 1 to 6, the presence of the products 1 can be detected transversely to the direction of movement of the products 1, in particular orthogonally relative to the conveyors 5,6.

According to another embodiment, as visible in Figures 7 and 8, the detection is always carried out transversely, from the side, but in a direction inclined relative to the longitudinal axis of one of the conveyors 5,6, in particular of the second conveyor 6. However, this detection remains orthogonal to the path of the products 1, during their guided passage from the first conveyor 5 to the second conveyor 6, in this configuration with the adjacent ends located side by side transversely. .

According to a preferred embodiment of the conveying method, as visible in the example of Figures 1 to 3, for a section, in the event of detection of a hole between two products 10,11, the second conveyor 6 is decelerated. until said two products 10,11 are brought together, then the second conveyor 6 is accelerated to the speed of said first conveyor 5.

According to one envisaged embodiment, the products 1 are delivered by the second conveyor 6 to an accumulation surface as a downstream station 4.

As mentioned above, the invention also relates to the conveying device 2.

Such a conveying device 2 is particularly suitable for implementing the conveying method described above.

Advantageously, such a conveying device 2 comprises at the first location 50 of said first conveyor 5, a first means 500 for detecting the presence of said products 1. Said first means 500 performs a detection of what is in its detection spectrum, namely that it constantly detects the presence or the absence of product 1.

Such detection can take place continuously or sequentially by suitable sensors as described above.

Thus, the interval between all the products 1 which have passed beyond the first detection means 500 is known. In particular, the first interval 7 between two given successive products 10,11 is known.

The conveying device 2 also comprises a means 12 for calculating said first interval 7 between the products 1, in particular between two given products 10,11, from said first location 50.

To do this, the conveying device 2 comprises means 13 for controlling the speed of said second conveyor 6, as a function of said first interval 7 with respect to said target pitch. It will be noted that the calculation means 12 and the control means 13 can be of any type, preferably in the form of software applications executed on suitable computer terminals, in particular a control unit of said conveying device 2, or even the central console of the production line incorporating such a device 2.

Advantageously, as visible in Figures 4 to 8, the conveying device 2 comprises at the second location 51 of said first conveyor 5, located downstream of said first location 50, a second means 501 for detecting said products 1.

Thus, the interval between all the successive products 1 which pass through the second detection means 501 is known and verified. In particular, the second intervals 8 between the products 1 are known.

In addition, the calculation means 12 also ensure the calculation of the second intervals between the products 1 as they pass through the second location 51 of said first conveyor 5.

Therefore, said control means 13 ensure an adjustment of the speed of the second conveyor 6 as a function of said second intervals 8.

According to one embodiment, as can be seen in FIGS. 8 and 9, the conveying device 2 comprises, at the third place 60 at the inlet of said second conveyor 6, a third means 600 for detecting said products 1.

Consequently, the calculation means 12 also ensure the calculation of third intervals 9 of said second conveyor 6.

It is then possible to compare the third intervals 9 with the target pitch, to verify that the result of the control applied to the second conveyor 6 complies with expectations, namely that the intervals between the products 1 indeed correspond to the target pitch. If this is not the case, it is still possible to intervene, because the third detection takes place at the upstream end of said second conveyor 6.

Thus, said control means 13 ensuring the control of the speed of the second conveyor 6 as a function of said third intervals 9.

By detecting at least the first interval 7 between the products 1 upstream, the invention allows their arrival and their passage to the second conveyor 6 to be anticipated.

This anticipation can be improved by recording as and when the checks already carried out and by modifying the future adjustments, by compensating the acceleration or deceleration values of the second conveyor 6, in order to refine the action carried out and the correct spacing between products 1. The invention, through a single first detection, supplemented by a second detection and / or a third detection, provides a system for regulating the flow of products 1, which is intended to be simple to set up and implement. Thus, it is in particular possible to obtain a constant and chosen interval between the products 1, for example when the products 1 arrive in an irregular flow. Such a regulation advantageously makes it possible to avoid a jam of the products 1, ensuring a modification of the intervals between the products 1 without them coming into contact with each other, and therefore without pressure detrimental to the integrity of the products 1. the invention offers the possibility of dispensing to a certain extent from an intermediate station between two conveyors, such as a product accumulation surface 1 generally intended to regulate a difference in regularity between the flows of a first upstream conveyor 5 at the outlet of a processing station and a second downstream conveyor 6. The invention therefore makes it possible to maintain the regularity of the downstream flow, even when the upstream flow is slowed down, in particular at the end of production and of the drop in the rate of a downstream processing station.

The invention can also provide for limiting the acceleration and deceleration actions applied to the second conveyor 6, in order to keep values below thresholds, generally called “maximum ramps”. Such thresholds are determined as a function of the products 1, but also of the conveyors 5, 6, to avoid an unwanted movement of the products 1 relative to their conveying surface during said accelerations and decelerations, or even to prevent their falling or falling. shocks.

If the regulation is not sufficient to obtain the target pitch of the second conveyor 6, in particular due to limitations below the ramps, the invention can provide for juxtaposing several conveying devices 2, one after the other and to apply the conveying process to each of them, in particular in an increasingly refined way from upstream to downstream.

Claims

1. Method of conveying products (1) from an upstream station (3) to a downstream station (4), in which:

- A first conveyor (5) is fed from said upstream station (3) with a single-line flow of products (1);

- the first conveyor (5) transports said flow at a determined speed to a second conveyor (6);

- Said products (1) pass directly from the first conveyor (5) to the second conveyor (6) which delivers said products (1) to the downstream station (4);

- a target pitch is determined between the products (1) on the second conveyor (6); said conveying method comprising at least the following consecutive steps:

- at a first location (50) of the first conveyor (5), the presence of said products (1) is detected;

- A first interval (7) is determined between two given successive products (10,11);

- A comparison is made between said first interval (7) and the target pitch;

- During the passage of said products (10,11) given at the second conveyor (6), the speed of said second conveyor (6) is controlled as a function of said comparison; said aforementioned steps being reproduced for all the products (1) of said stream; characterized in that it further comprises the following steps:

- Detecting, at a second location (51) of said first conveyor (5) downstream of said first location (50), the presence of said products (1);

- Second intervals (8) between the products (1) are determined;

- The speed control of said second conveyor (6) is adjusted as a function of said second intervals (8).

2. Conveying method according to the preceding claim, characterized in that it further comprises a step of comparing the first intervals (7) and the second intervals (8); the adjustment step being carried out according to said comparison between the first intervals (7) and the second intervals (8).

3. Conveying method according to any one of the preceding claims, characterized in that it further comprises a step of determining an average of said second intervals (8) over a section of said flow; the adjustment step being carried out as a function of said average of said second intervals (8).

4. Conveying method according to any one of the preceding claims, characterized in that it further comprises the following steps:

- Detecting, at a third location (60) at the inlet of said second conveyor (6), the presence said products (1);

- Third intervals (9) between the products are determined;

- The speed control of said second conveyor (6) is adapted as a function of said third intervals (9).

5. Conveying method according to the preceding claim, characterized in that it further comprises a step of comparing the third intervals (9) and the target pitch; the adaptation step being carried out as a function of said comparison between the third intervals (9) and the target pitch.

6. Conveying method according to any one of claims 4 or 5, characterized in that it further comprises a step of determining an average of said third intervals (9) over a section of said flow; the adaptation step being carried out as a function of said average of said third intervals (9).

7. Conveyor method according to any one of the preceding claims, characterized in that in the event of detection of a hole between two products (1), the second conveyor (6) is decelerated until said two products are brought together ( 1); then the second conveyor (6) is accelerated to the speed of said first conveyor (5).

8. Conveying method according to any one of the preceding claims, characterized in that the products (1) are delivered by the second conveyor (6) to an accumulation surface as a post (4) downstream.

9. A method of conveying according to any one of the preceding claims, characterized in that the step of detecting the presence of said products (1) is carried out continuously.

10. Device (2) for conveying products (1) from an upstream station (3) to a downstream station (4), comprising at least:

- a first conveyor (5) circulating at a determined speed and supplied with a single-line flow of products (1) by said upstream station (3);

- a second conveyor (6) located directly downstream of said first conveyor (6) and delivering said products (1) to said downstream station (4);

- a target pitch being determined between the products (1) on the second conveyor (6); said device (2) further comprising:

- at a first location (50) of said first conveyor (5), a first means (500) for detecting the presence of said products (1);

- means (12) for calculating first intervals (7) between the successive products (1), as a function of the information collected by said first detection means (500);

- means (13) for controlling the speed of said second conveyor (6), as a function of said first intervals (7) with respect to said target pitch characterized in that it comprises:

- at a second location (51) of said first conveyor (5) and located downstream of said first location (51), second means (501) for detecting the presence of said products (1);

- said calculation means (12) ensuring the calculation of second intervals (8) between the products (1) of said first conveyor (5), as a function of the information collected by said second detection means (501);

- Said control means (13) ensuring the adjustment of the speed of the second conveyor (6) as a function of said second intervals (8).

11. Conveyor device (2) according to the preceding claim, characterized in that the first conveyor (5) and / or the second conveyor (6) are of the endless belt type.

12. Device (2) for conveying according to any one of claims 10 or 11, characterized in that it comprises:

- at a third location (60) at the inlet of said second conveyor (6), a third means (600) for detecting the presence of said products (1); - said calculation means (12) ensuring the calculation of third intervals (9) between the products

(1) of said second conveyor (6), based on the information collected by said third detection means (600);

- Said control means (13) ensuring the adjustment of the speed of the second conveyor (6) as a function of said third intervals (9).

13. Device (2) for conveying according to any one of claims 10 to 12, characterized in that said first means (500) and / or second means (501) and / or third means (600) for detecting products ( 1) include at least one continuous type sensor.