WO2024150126A1

WO2024150126A1 - Automated modular device for transferring paste-like material

Info

Publication number: WO2024150126A1
Application number: PCT/IB2024/050197
Authority: WO
Inventors: Loïc LECERF; Quentin MARGEOT
Original assignee: Fairme
Priority date: 2023-01-13
Filing date: 2024-01-09
Publication date: 2024-07-18
Also published as: FR3144906A1

Abstract

The invention relates to a device for transferring a material between elements of a modular system, comprising a treatment compartment (20) with drawers, configured to receive a plurality of drawer modules; inserted into the compartment, a drawer source module (30) containing the material; a drawer robot module (80) inserted above the source module, incorporating a robot configured to collect material from the source module located below; and a drawer receiving module (90) inserted under the robot module. The source module (30) and the receiving module (90) have relative mobility between a first position wherein the robot module has access to the source module in order to collect material, and a second position wherein the robot module has access to the receiving module in order to deposit the collected material.

Description

Modular automated pasty material transfer device

The invention relates to the small-scale automated production of dairy products, and more generally of liquid or pasty food products.

Background

Dairies use large-scale industrial processes to produce a range of dairy products ready for sale in supermarkets. Dairies are generally located far from production farms, and they are supplied with raw milk by refrigerated tankers that collect milk from farms.

Dairy products from local production involve essentially manual processes, because industrial processes are not adapted to the small quantities produced individually by farms.

Many milk producers forego local production due to lack of time to devote to the largely manual processes involved.

Summary

We generally provide an automated production unit for food products involving a liquid or pasty base material, comprising processing compartments with drawers, each configured to receive several drawer modules; drawer tank modules each integrating a tank to contain the base material, the tank being open from its upper face; and a shuttle for transporting modules between compartments and organizing modules in the same compartment. All storage and transport of raw material during processing takes place exclusively in drawer modules.

The production unit may further comprise a drawer processing module configured to be placed near a tank module in a compartment and perform operations on the contents of the tank module; and a spray washing device configured in one of the compartments to receive and wash the drawer modules.

The drawer processing module may be a robot module configured to be placed above the tank module and integrating a movable wrist in the plane of the robot module to work with a tool on the contents of the tank module.

The drawer treatment module may be a transfer module configured to be placed above the tank module, the transfer module including a tank and a nozzle connected to the tank by a pump, the nozzle being movable between a high storage position and a low active position capable of penetrating into the tank module.

The transfer module can integrate a robot configured to move the nozzle above pots placed in the tank module to distribute the contents of the tank of the transfer module.

The shuttle can insert a receiving module between the robot module and the tank module in the compartment, the receiving module being configured to move between a position out of the compartment where the robot module accesses with a sampling tool the contents of the tank module , and a retracted position in the compartment where the robot module places the contents taken from the tank module on the receiving module.

Each tank may include at its bottom a drain valve configured to be opened when the corresponding module is inserted into the washing device.

Each tank may include a removable cover, the cover comprising a device for stirring the contents of the tank; at least one orifice configured to receive a nozzle by insertion from above; and a gripping device configured to cooperate with a cover removal device.

The drawer processing module may be a drawer bain-marie module configured to be placed under a tank module in a compartment, the bain-marie module including a drawer plate carrying a lifting device; and a drawer bain-marie tank carried by the lifting device.

There is also provided a process for the automated production of food products involving a liquid or pasty base material, comprising steps consisting of storing and transporting the liquid or paste base material exclusively in mobile tanks configured as drawer modules; and transporting the tanks between processing compartments configured to receive the drawer modules.

The method may further comprise steps consisting of performing operations on the contents of a tank using a device configured as a drawer module inserted in a compartment near the corresponding tank; and wash the drawer modules in a dedicated compartment where the modules are transported after use.

There is also provided a device for transferring a material between elements of a modular system, such as the aforementioned production unit, comprising a processing compartment with drawers, configured to receive several drawer modules; inserted in the compartment, a drawer source module containing the material; a drawer robot module inserted above the source module, integrating a robot configured to take material from the source module located below; and a drawer receiving module inserted under the robot module. The source module and the reception module have relative mobility between a first position where the robot module has access to the source module to pick up material, and a second position where the robot module has access to the reception module to deposit the picked material .

The source module can integrate a tank containing the material in liquid, pasty or powder form and the robot module can be configured to pick up and deposit the material using a ladle mobilized by a CNC machine.

The reception module can carry containers intended to receive the deposited material.

The reception module can be movable between a position taken out of the compartment and a position entered into the compartment.

The receiving module may include a frame inserted into the compartment; telescopic arms arranged in the sides of the frame, carrying a receiving tank; and a pinion meshing with a rack fixed on an end segment of at least one of the telescopic arms.

Summary description of the drawings

Embodiments will be explained in the following description, given on a non-limiting basis in relation to the attached figures, among which:

There shows a schematic top view of an automated small-scale dairy production unit;

There represents a top perspective view of an embodiment of a drawer tank module with a cover;

There represents a side sectional perspective view of the tank drawer module of the ;

There represents a perspective view of an embodiment of a bain-marie drawer module;

There represents a top perspective view of an embodiment of a drawer transfer module;

There represents a side perspective view of the drawer transfer module of the ;

There represents a perspective view of an embodiment of a transfer module integrating a manipulator robot;

There represents a perspective view of an embodiment of a drawer robot module operating on the contents of a tank module;

There represents a perspective view of an embodiment of a drawer robot module in a phase of taking a dose of dairy product from a tank module;

There represents the drawer robot module of the in a phase of dispensing a dose of dairy product in a container carried by a drawer receiving module;

There and the represent perspective views from two different angles of a spray washing device made by drawer modules housed in a drawer compartment.

detailed description

The embodiments described below aim for production of dairy products that is both local on a small scale and fully automated. Production is ensured by a production unit preferably entirely contained in a transportable enclosed shelter, for example a maritime container, which is installed on site at the milk producer's farm. The production unit can thus be supplied directly with milk from milking, thus ensuring optimal quality of raw milk and savings in transport.

The small scale of automated production opens up certain possibilities that are not possible in large-scale production. The production unit can in particular work on demand, namely take an order from a consumer electronically, organize production, and make the product available when the consumer goes on site.

All production of food products, especially dairy products, is subject to particularly strict hygiene standards, which represent a challenge when one wants to apply them in fully automated production on a small scale. In particular, any item likely to be in contact with milk or to be splashed must be washed after use according to recommended procedures. Below we present a certain number of solutions allowing automation while respecting hygiene standards without human intervention.

There illustrates a top view of one embodiment of such a production unit. The unit comprises a multitude of drawer compartments of similar dimensions organized along a service corridor 10, preferably on either side of the corridor. The compartments are designed to receive in any vertical positions drawer modules of standardized dimensions, introduced and extracted by a shuttle 12 which is movable in the axis of the service corridor. The shuttle 12 is shown moving a module shown in dotted lines into a compartment. The drawer modules have different functions explained below and can have a height that is a multiple of a standardized unit height U corresponding to the vertical pitch of the slides arranged in the compartments.

As an example of installation, two finished product storage compartments 14 are shown on either side of the corridor 10, a milk supply and pre-treatment compartment 16 facing a refrigerator compartment 18 , a mechanical operations compartment 20 facing an input storage and distribution compartment 22, a washing compartment 24 facing an oven compartment 26, and two cellar compartments 28 on either side of the corridor.

The feeding and pre-treatment compartment 16 may be provided with farm milk supply pipes 16-1 and water supply pipes 16-2. These pipes can end in retractable nozzles arranged at the level of the ceiling of compartment 16.

Depending on thermal insulation or waterproofing requirements, certain compartments can be closed by two half-height doors which slide vertically against each other. Thus, depending on the height at which a module is introduced or extracted from a compartment, a high door is lowered, or a low door is raised to allow passage.

A special feature of the production unit is that all stages of the production process involving contact with milk, including mechanical operations, are carried out by mobile drawer modules inserted into the compartments. All these drawer modules, including those designed to carry out mechanical operations, are configured to resist spraying and can therefore, after use, be moved to undergo washing by spraying in the washing compartment 24. The washing device used can be industrial dishwasher type.

Liquid or pasty products used in production are stored and transported exclusively in mobile tank modules between processing stations. Transfers take place directly from one tank to another of two modules which are brought together for the occasion in a compartment, without going through external circuits.

Figures 2A and 2B show perspective views from above and in side section of an embodiment of a drawer tank module. There also shows horizontal grooves forming slides in the side walls of the compartment receiving the module. The module, 1U high, includes a tank 30 of parallelepiped shape with rounded corners which occupies practically the entire volume of the drawer. The upper face of the tank is open and preferably closed by a removable cover 32. The edges of the tank are folded horizontally, and the side edges, set back from the side walls of the compartment, are fixed on flanges 34 in low friction material that slide into the grooves of the compartment to perform the drawer function.

As we see in , the bottom of the tank is preferably provided with a valve 36 which remains closed in a sealed manner during the entire manufacturing process. This valve is configured to be opened when inserting the module into the washing compartment, in order to evacuate the washing water.

The cover 32 can be provided, in its center, with a stirring device comprising, on the exterior side, a waterproof housing 38 integrating a motor and, on the interior side visible at the , a stirring propeller 40. Preferably, to facilitate sealing for washing, the motor is powered by a battery housed in the housing 38, and the control is carried out wirelessly, for example Wifi or Bluetooth. Recharging the battery can also be carried out wirelessly, by a suitable charging device arranged at locations where the module is installed or stored waiting for use.

Various other electrical elements can be connected to the housing 38, such as a temperature sensor plunger 41.

The cover may also include a gripping device comprising three studs 42 provided with notches oriented towards the rear, configured to cooperate with a cover removal device, such a removal device being provided in the washing compartment 24.

Finally, the cover includes one or more orifices 44 giving access to the contents of the tank 30. As shown, these orifices can be closed by flexible lips which yield under the pressure of a nozzle that a module placed above can insert through these holes.

There represents a perspective view of an embodiment of a drawer bain-marie module 50. The bain-marie module 50, of height 2U, is shown inserted immediately under a tank module 30. It includes a tank 30b adapted to the tank 30 , the lateral edges of which rest on shoulders of the wall of the compartment under the drawer grooves receiving the tank module 30. The walls above these shoulders are hollowed out, as shown, so that the tank 30b can rise towards the tank 30.

The tank 30b is placed on a lifting device 52 comprising a plate mobilized by a crossed arm and cylinder mechanism. This mechanism is integral with a drawer tray 54 inserted in grooves two positions lower than the shoulders receiving the tank 30b. This tank 30b, if it is intended to heat, can be provided at its bottom with an electrical resistance to maintain the water bath at the desired temperature. This electrical resistance as well as the jack of the lifting device can be powered by a connector arranged on the rear edge of the plate 54 and which engages in a socket at the bottom of the drawer when the module is inserted into the compartment. Alternatively, the tank can be heated by an induction system arranged in the lifting platform, which allows the same type of tank to be used for all operations.

In operation, the tank module 30 is first filled, for example by inserting it into the upper location of the supply and pretreatment compartment 16, that is to say just under the ceiling of the compartment. As previously indicated, this ceiling is equipped with milk and water supply nozzles. These nozzles are retractable to allow the insertion of the tank module 30, and are deployed by penetrating through the orifices 44 of the cover 32 to fill the tank.

To free this filling station, the tank module is transported by the shuttle 12 to a suitable processing station, for example lower in the same compartment 16, where drawers designed for the bain-marie module are provided (with a socket power supply and a recessed wall to allow the elevation of the bain-marie module tank).

The bain-marie module 50 is brought by the shuttle 12 to a filling station, for example in the supply compartment 16, where the tank can be filled with water. The bain-marie module is then transported to its implementation location under the tank module 30. The lifting device 52 is actuated and brings the hot water from the tank 30b into contact with the walls of the tank 30. The lifting device stirring 38, 40 of the cover of the tank module 30 can be actuated to promote heat transfer.

The bain-marie module can also be used to cool the contents of a tank module, for example to prepare ice cream or carry out a pasteurization cycle, involving a phase of rapid temperature rise thanks to a first bain-marie module, followed by a rapid cooling phase thanks to a second water bath module. This second bain-marie module can contain glycol and have its implementation station in a freezing zone of the refrigerator compartment 18.

The tank 30b of the bain-marie module can be an independent tank module which is not integral with the plate of the lifting device 52. Thus, any available tank module can be used to serve as a bain-marie tank, at least for the bain-marie. cooling water heater, which does not have a heating resistor integrated into the tank. The lifting device 52 and the tank module 30b can thus be managed individually, increasing the flexibility of the production unit.

Figures 4A and 4B represent a top and side perspective view of an embodiment of a drawer transfer module, used for any transfer of liquid dairy product from a tank module to another container, or to introduce inputs in tank modules.

The transfer module, 1U high, is shown above a tank module 30 inserted in the same compartment. It includes a tank 60 of height 1U only partially occupying the volume of the drawer. The unoccupied space of the drawer houses a transfer device including a pipe 62 connected to a pump 64. The pump 64 can be of the peristaltic type, as shown, to precisely meter the volumes transferred. The tank 60 and the transfer device are supported by a plate 66 (visible only at the ) configured to slide in the compartment slides and provide the drawer function.

As shown, the pipe 62 comprises a first segment which enters the tank 60 through an orifice in a cover closing the tank. A second segment of the pipe 62 goes from the pump 64 towards a vertical nozzle 68 facing one of the orifices 44 of the cover of the tank 30 located below. The nozzle 68 is in this embodiment fixed to a vertical translation device including a screw jack 70 driven by a motor 72. The motor 72 and the pump 64 can be powered independently by a battery and be controlled wirelessly, like the mixing device 38 of the tank module. In the , the nozzle 68 is shown in a high storage position, where it is contained in the 1U height of the drawer module, so as not to interfere with the sliding of the drawer module. In the , the nozzle 68 is shown in a low active position where it projects from the lower plane of the module and enters the tank 30 located below.

In passing, we see in the an example of configuration of a side edge of the tank module 30, more precisely of a flange 34 performing the drawer function. The lower face of the flange 34 may include a rack which cooperates with a pinion at the end of a telescopic arm of the shuttle 12. This makes it possible to push the modules to the bottom of the drawer by limiting the length of the telescopic arms.

The transfer module can be used in several modes. In a first mode, corresponding to the configuration shown, the tank 60 of the transfer module is filled from the contents of the tank 30. In this case, the nozzle 68 is lowered to reach the bottom of the tank 30 and the pump 64 is actuated to suck into the tank 30 and discharge into the tank 60.

In another mode, the tank 60 contains a product to be transferred, for example into a tank 30 arranged according to the configuration shown. In this case, the pump 64 is actuated to draw into the tank 60 and discharge into the tank 30. The nozzle 68 can be lowered partially to remain above a liquid level in the tank 30. The brewing device 38 , 40 of the cover of the tank 30 can be actuated to ensure homogeneous mixing of the product distributed by the nozzle.

In another mode, the tank 60 is pre-filled with a liquid product to be distributed, for example milk including ferments for making yogurt. The transfer module can be placed above a drawer robot module, for example a CNC ("Computer Numerical Control") type machine equipped with a gripper configured to grip the nozzle 68 and move it above pots carried by a drawer receiving module located under the robot module. The receiving module can be a tank module 30 at the bottom of which the pots have been placed by a robot module in another station. Thus, any splash of dairy product during the operation is collected in the tank module, which can then be moved to be washed in compartment 24.

In yet another mode, the transfer module can be used to discharge the contents of its tank into a pipe, for example to wash the milk supply pipe 16-1.

There represents a variant of transfer module dedicated to this third mode of use, namely the filling of pots. According to this variant, the transfer module integrates the robot which manipulates the nozzle, and the nozzle remains attached to a manipulator arm of the robot.

The robot can be battery powered and controlled wirelessly. However, if a battery is insufficient given the energy required by the robot, we can consider powering it via an electrical connector on the rear panel which snaps into a socket at the bottom of the drawer.

There represents a perspective view of an embodiment of a drawer robot module 80 operating on the contents of a tank module 30 located below. The robot module includes a two-axis CNC machine integrated into a frame with slides to provide drawer functionality. The two axes mobilize a tool-carrying wrist 82 in a plane above the tank 30. The wrist 82 here carries a spatula used, for example, in a phase of cutting curds contained in the tank 30. As is shown, the wrist may include a motor with a vertical axis which serves to change the orientation of the spatula depending on the direction of the cutting. The spatula can be replaced by other tools, for example a whisk which is rotated by the vertical axis motor.

The different interchangeable tools can be stored in a tool magazine in the form of a drawer module placed above the robot module. The wrist is then articulated, as shown, by a horizontal axis used to tilt the wrist upwards to change the tool. The tool magazine can be moved vertically to pick up or place a tool on the wrist facing upwards. The tool can be held in the wrist and in the magazine by a snap or magnetic system.

The tool store module, receiving tools which have been brought into contact with the milk, can, like the other modules, be moved and washed with all its tools in the washing compartment 24 after use.

Figures 6A and 6B represent perspective views of an embodiment of a drawer robot module in two phases of a transfer of pasty dairy product into containers carried by a drawer receiving module. The pasty state is less suitable for transfer by pipe or pumping.

The example of operation carried out is a ladle molding of curdled milk in pots. This operation is carried out using three stacked drawer modules, namely a tank module 30 placed at the bottom, a receiving module 90 in the middle, and a robot module 80 above. The robot module 80 is similar to that of the , the wrist being equipped with a motorized ladle 92 to tilt around a horizontal axis.

The reception module 90, 1U high, is similar to a tank module as described previously. The tank of this reception module 90 here contains a batch of pots, namely pierced containers to evacuate the whey from the curdled milk that is placed there. A particularity of this module is that the tank is mobile during operations between an almost extracted position ( ), where the ladle 92 has access to the entire lower tank 30, and a position at the bottom of the drawer ( ), where the ladle has access to the pots.

In the phase of , the ladle is lifted by the wrist, tilted backwards and moved over an area of curdled milk to be collected. As the curdled milk is pasty and flows little to fill the sampling holes, the samples are taken with a ladle in successive steps to cover the entire surface of the tank 30. When the sampling area is reached, the ladle is gradually lowered by the wrist and tilted forward, in a digging motion, until the ladle is horizontal. The wrist is then raised while maintaining the horizontal position of the ladle.

The tank 90 is then returned to the compartment, at least sufficiently so that the ladle can reach the dish to be filled. The position of the , at the bottom of the drawer, corresponds to an extreme position allowing the ladle to reach the dowels located closest to the front edge of the tank 90. When the dowel is reached, the wrist is lowered and the ladle is tilted to deposit its contained in the fascisselle.

When the pots are filled, the tank 90 is transported by the shuttle to a rest area, for example a cellar compartment 28, where the pots are allowed to drain. When the pots are ready, the tank 90 can be placed in a station similar to that of Figures 6A, 6B, where the pots are, for example, unmolded into another tank module by a robot module manipulating the pots using 'a pliers. The pliers can be one of the tools adaptable to the wrist of a CNC machine of the type in Figures 5, 6A and 6B.

The whey remaining in the faitselles tank can be transferred to other tanks using a transfer module of the type in Figures 4A and 4B, with a view to being valorized, for example to make Ricotta.

The module 90 could be identical in every respect to a tank module as described previously. Then the movement of the tank between the position at the bottom of the drawer and the extracted position could be carried out by the shuttle 12.

Preferably, in order not to take up the shuttle, the module 90 is configured to move its tank autonomously. For this, according to one embodiment, the module 90 is integrated into a frame 94 slid into the bottom of the drawer. This frame has telescopic arms 96 on its sides on which the side edges of the tank rest. To ensure the movement of the tank, the end segment of at least one of the telescopic arms is fixed to a rack which meshes with a motorized pinion 98 arranged in the wall of the compartment, as shown.

Since the pinions 98 are thus secured to the wall of the compartment, this type of processing station is implemented at a fixed location in a compartment, for example the operations compartment 20 which can be dedicated to this and include several stations of this type distributed over its height.

Given the overhang caused when the tank is in the extracted position, it is preferable to securely fix the frame 94 in the compartment. In any case, this frame can only be used at the fixed location where the pinions 98 are located. The tank of the module 90 can form a classic tank module 30 whose lateral edges, more precisely the flanges 34 ( ), come to rest on the telescopic arms 96 instead of resting in horizontal grooves in the walls.

With this configuration, in principle, the fixed elements such as the frame 94 and the pinions 98 are not subject to splashes of dairy product, and do not need to be regularly washed after use. The elements in contact with the milk are the tanks 30 and 90, and the robot module 80, in particular the ladle and the wrist. All of these elements are part of modules that can be moved to compartment 24 to be washed.

According to a variant, the modules 30 and 90 can be exchanged, and it is the tank 30, then in the middle, which is entered or extracted from the compartment during operations.

According to another embodiment, the modular structure of Figures 6A and 6B can be configured to return cheeses during ripening, and more generally transfer objects from a source drawer module to the reception module 90. For turning of cheeses, the cover of the tank module 30 (the source module) is replaced by a perforated plate carrying the cheeses to be turned, and the reception module 90 is also a tank module whose cover is replaced by a perforated plate. The robot is then equipped with a gripper capable of encircling each cheese and tilting it 180° during its movement towards the receiving module.

The structure of Figures 6A and 6B offers a generic modular solution for carrying out an automated transfer from one module to another of any liquid, pasty or powdery material contained in a tank, or of individual objects carried on a plate. The device can be used in applications not subject to health constraints, to transfer non-perishable materials in an automated process.

Figures 7A and 7B show perspective views from two different angles of a spray washing device housed in compartment 24. The washing device is similar to an industrial dishwasher. The lower part of the device is made by a 3U height drawer module integrating a receiving tank 100, a pump 102 and a sprinkler 104 powered by the pump. A heating resistor can be provided at the bottom of the tank or in the pump. The drawer module can be designed to be placed at different heights. For this, its rear face can be fitted with electrical and hydraulic connectors (inlet and outlet) which cooperate with corresponding sockets fitted in the back wall of the compartment.

The upper part of the washing device is made by a drawer module of height 1U or 2U, essentially a plate 106 forming the ceiling, under which a sprinkler 108 is arranged. The sprinkler 108 is supplied with water by the pump 102, by a pipe which passes outside the compartment, possibly via other hydraulic connections fitted in the back wall of the compartment.

As shown, the ceiling plate 106 comprises three pistons 110 sliding vertically inside the washing device. The pistons have a shoulder at their end to cooperate with the gripping devices 42 of the tank covers, and to remove the cover from a tank when it is inserted into the washing device. The lid and the bowl can then be washed separately.

A robot module is shown in the washing device.

Washing the transfer modules requires two operations, one to wash the tank 60, the other to wash the pipe 62. Thus, for example, when a transfer module is being washed, the drain valve of the tank can be closed during a given phase, so that the tank partially fills with washing product. Pump 64 is then actuated to draw into the tank and discharge through nozzle 68, which washes the interior of the pipe, pump and nozzle. The same procedure can be repeated during a rinsing phase.

In the above, we have exposed a subset of elements of an automated production unit for dairy products which are subject to washing constraints. All these elements have been organized thanks to a certain number of technical solutions so that they are in mobile modules which can be easily moved to be washed, in particular automatically in a suitable washing device.

The modularity and mobility of all these elements, particularly the robot modules, also facilitates maintenance operations. Indeed, when a defective module is detected, the shuttle can replace it by interchanging it with an identical backup module. An airlock accessible from the outside can be provided in one of the compartments where the shuttle inserts modules diagnosed as defective. When a defective module is detected, a maintenance service is notified so that it can remove the defective module from the airlock and place an equivalent replacement module there.

Although the context of dairy production was used as the main example, the modular system described applies to other food products that go through a phase where they are liquid or pasty, i.e. say transferable by pumping or ladling, such as compotes, jams, syrups, sorbets, etc.

Claims

Device for transferring a material between elements of a modular system, comprising:
a drawer processing compartment (20), configured to receive a plurality of drawer modules;
inserted into the compartment, a drawer source module (30) containing the material;
a drawer robot module (80) inserted above the source module, integrating a robot configured to pick up material from the source module located below; And
a drawer receiving module (90) inserted under the robot module; And
the source module (30) and the reception module (90) having relative mobility between a first position where the robot module has access to the source module to take material, and a second position where the robot module has access to the processing module reception to deposit the collected material.
Device according to claim 1, in which the source module integrates a tank (30) containing the material in liquid, pasty or powder form and the robot module (80) is configured to pick up and deposit the material using a ladle (92) mobilized by a CNC machine.
Device according to claim 1, in which the reception module (90) carries containers intended to receive the deposited material.
Device according to claim 1, in which the reception module (90) is movable between a position taken out of the compartment and a position entered into the compartment.
Device according to claim 4, in which the reception module comprises:
a frame (94) inserted into the compartment;
telescopic arms (96) arranged in the sides of the frame, carrying a receiving tank (90); And
a pinion (98) meshing with a rack fixed on an end segment of at least one of the telescopic arms.