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Title:
PNEUMATIC CONVEYOR SYSTEM FOR FABRIC
Document Type and Number:
WIPO Patent Application WO/2022/069300
Kind Code:
A1
Abstract:
A pneumatic conveyor system of damp fabric for fabric processing machines, comprising - a transit tunnel, - at least one air blower device provided in said tunnel, comprising at least a first and a second channel, diverging from each other and inclined with respect to the direction of extension of said tunnel, which flow into said tunnel to convey air respectively according to an inclined direction converging in a first direction of feed of the fabric in said tunnel and according to an inclined direction converging in a second direction of feed of the fabric opposite said first direction, in order to produce a movement pushing on the fabric alternately in the two directions of convergence, so that when the first channel is active, i.e., the air passes through the first channel and not through the second channel, the fabric is moved in said first direction of feed, while when the second channel is active, i.e., the air passes through the second channel and not through the first channel, the fabric is moved in said second direction of feed.

Inventors:
SANCHINI STEFANO (IT)
Application Number:
PCT/EP2021/075985
Publication Date:
April 07, 2022
Filing Date:
September 21, 2021
Export Citation:
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Assignee:
PENTEK TEXTILE MACHINERY S R L (IT)
International Classes:
D06B3/28; D06C19/00; F26B13/20
Foreign References:
US20170067196A12017-03-09
EP2535451A12012-12-19
ITFI20040183A12004-11-25
ITFI20080100A12009-11-20
US20170067196A12017-03-09
Attorney, Agent or Firm:
MANNUCCI, Michele et al. (IT)
Download PDF:
Claims:
Claims

1. A pneumatic conveyor system (100) of damp fabric for fabric processing machines, comprising:

- a transit tunnel (15),

- at least one air blower device (20, 21) provided in said tunnel (15), comprising at least a first and a second channel (20B’, 20B”, 21B’. 21B”), diverging from each other and inclined with respect to the direction of extension of said tunnel (15), which flow into said tunnel (15) to convey air respectively according to an inclined direction converging in a first direction of feed of the fabric in said tunnel and according to an inclined direction converging in a second direction of feed of the fabric opposite said first direction, in order to produce a movement pushing on the fabric alternately in the two directions of convergence, so that when the first channel (20B’, 20B”) is active, i.e., the air passes through the first channel and not through the second channel, the fabric is moved in said first direction of feed, while when the second channel (2 IB’. 21B”) is active, i.e., the air passes through the second channel and not through the first channel, the fabric is moved in said second direction of feed,

- a variation device (30) of the dimensions of the area of a section of the channels (20B’, 20B”, 21B’. 21B”) of said at least one blower device (20, 21), in order to adjust the air pressure delivered from said channels (20B’, 20B”, 21B’. 21B”), obtaining a variation of the speed of the fabric in the tunnel (15), wherein said variation device (30) of the dimensions of the area of a section of the channels of said blower device comprises a closing body (31) of the outlet port (25) of a respective channel (20B’, 20B”, 21B’. 21B”) in said tunnel (15), adapted to take a plurality of positions for blocking said outlet port (25), from an initial position with said outlet port (25) open to a final position with said outlet port (25) at least partly blocked.

2. The pneumatic system according to claim 1, wherein said closing body (31) is a moving bulkhead (31.1, 31,2, 31,3, 31.4) positioned at an end portion of a wall of a respective channel (20B’, 20B”, 21B’. 21B”), so that the face of said bulkhead facing said channel (20B’, 20B”, 21B’. 21B”) defines an end portion of said channel and the free end (31 A) of said bulkhead defines part of the edge of said outlet port (25) of the channel into the tunnel (15), so that a movement of said bulkhead from said initial position toward said final position causes a narrowing of the end portion of the tunnel (15) and of the outlet port (25).

3. The pneumatic system according to claim 2, wherein said moving bulkhead (31.1, 31,2, 31,3, 31.4) is hinged to an end portion of a wall of the respective channel (20B’, 20B”, 21B’. 21B”), so that its movement between said initial position and said final position is a rotary movement.

4. The pneumatic system according to one or more of claims 1 to 3, comprising at least a first said blower device (20) arranged on the upper part of said tunnel (15), and at least a second said blower device (21) arranged on the lower part of said tunnel (15); preferably, the outlet ports (25) of respective channels (20B’, 20B”, 21B’. 21B”) of the two blower devices (20, 21) in the tunnel (15) being provided at a same longitudinal position along the tunnel (15).

5. The pneumatic system according to one or more of claims 1 to 4, wherein said closing body (31) is provided in each first and second channel (20B’, 20B”, 21B’. 21B”).

6. The pneumatic system according to one or more of claims 1 to 5, wherein said variation device (30) comprises a mechanism (35) for the simultaneous movement of the closing bodies (31) of said first and second channel (20B’, 20B”, 21B’. 21B”); preferably there being provided a single movement actuator (36) and movement transmission members kinematically connected to said single actuator (36) adapted to simultaneously move said closing bodies (31) of said first and second channel (20B’, 20B”, 21B’. 21B”) based on the actuation of said actuator (36).

7. The pneumatic system according to claims 4 and 6, wherein said mechanism (35) for simultaneous movement simultaneously moves all the closing bodies (31) of the correspondingly facing first and second blower devices (20, 21) positioned on the upper and lower parts of said tunnel (15).

8. The pneumatic system according to one or more of the preceding claims, wherein there is provided a device for closing the channels (20B’, 20B”, 21B’. 21B”) when they are not active and more preferably a device for closing the outlet ports (25) in the tunnel (15) when the channels (20B’, 20B”, 21B’. 21B”) are not active, so as to prevent the air passing through said tunnel from leaking into channels that are not active.

9. The pneumatic system according to claim 8 and one or more of claims 1 to 5, comprising a plurality of said blower devices (20, 21) provided in the upper and lower part of said tunnel (15), such as to push the fabric in the desired direction both from above and from below, and wherein each closing body (31) of the channels (20B’, 20B”, 21B’. 21B”) of said blower devices (20, 21) is adapted to take a plurality of blocking positions of said outlet port (25), from an initial position in which said outlet port is not blocked to a final position with said outlet port (25) completely blocked, or closed, and wherein, during pushing of the fabric by the air passing through the active channels, each variation device (30) positions, in the channels that are not active, the respective closing bodies (31) in said final closed position, so as to prevent the air passing through said tunnel from leaking into the channels that are not active.

10. The pneumatic system according to claim 9, wherein, given a pair of correspondingly facing blower devices (20, 21) positioned in said tunnel (15), said pneumatic system (100) is provided with a first mechanism (135) for simultaneously moving the closing bodies (31) of the first channels (20B’, 21B’) of the two upper and lower blower devices (20, 21), and a second mechanism (135A), independent from the first mechanism (135), for simultaneously moving the closing bodies (31) of the second channels (20B”, 21B”) of the two upper and lower blower devices (20, 21), so as to be able to adjust the air flow delivered from both first or both second channels, and to be able to close the first or the second channels when not active to prevent air from leaking into them; preferably respective actuation assemblies being provided for said first and said second mechanism (135, 135 A).

11. The pneumatic system according to one or more of the preceding claims, wherein said blower device (20, 21) comprises at least one flow diverter (20C, 21C) operating in at least two positions, a first position for closing said first channel (20B’, 21B’) to convey air into said second channel (20B”, 21B”), and a second position for closing said second channel (20B”, 21B”) to convey air into said first channel (20B’, 2 IB’).

12. A machine (10) for processing a fabric, comprising:

- a movement path (11) for the damp fabric between two processing areas,

- chambers located upstream and downstream of at least one section of said path (11) and inside which the fabric is adapted to enter according to the direction of movement to carry out a process,

- a pneumatic conveyor system (100) for conveying said damp fabric along said path according to one or more of the preceding claims.

13. A method for moving a fabric that provides for pulling or pushing the fabric in a tunnel, by means of jets of air above and below a fabric being processed, alternately toward opposed chambers into which the fabric is adapted to enter, the directions of said jets of air being inclined with respect to the horizontal so as to create a resulting horizontal pushing or pulling component of the air on the fabric that allows it to be moved, wherein said jets of air enter said tunnel from a plurality of channels with opposed inclinations, characterized in that said channels with opposed inclinations have respective closing bodies of the outlet ports of the channels in the tunnel, movable with respect to the walls of the channels, said method providing for adjusting the position of said closing bodies in said channels in order to vary the dimensions of the outlet port, thereby adjusting the pressure of the jets of air delivered from said channels.

Description:
PNEUMATIC CONVEYOR SYSTEM FOR FABRIC

Description

Technical field

[0001] The present invention relates to the field of machinery for processing fabrics, and more in particular to a pneumatic conveyor system for fabric.

[0002] The invention also relates to a machine for processing fabric comprising said conveyor system, and to a method for moving a fabric.

Background art

[0003] Machines for the continuous processing of a fabric that improve the tactile characteristics thereof, and in particular surface softness and shrinkage, have been known for some years now. Among the various prior art machines there are known, for example, machines that impact a damp fabric between two impact structures located at the ends of a pneumatic conveying tunnel of the fabric. This impact causes softening, shrinkage and settling of the fabric. Machines of this type are described, for example, in the Italian patent applications FI2004A000183, FI2008A000100, and in US 2017/067196 Al

[0004] In the first two applications cited, the fabric is fed between two collection tanks upstream and downstream of the tunnel, in which a fabric bath may or may not be provided. The central area of the tunnel is provided, both on the upper and lower parts, with two air ejection areas, each having an air blower device comprising two channels for conveying air toward the tunnel; the channels extend from a storage tank, which is connected to an air movement system. More in particular, each blower device (lower on the bottom of the tunnel, and upper on the top of the tunnel) has two channels, diverging from the storage tank toward the tunnel, i.e., inclined with respect to the direction of extension of the tunnel and of feed of the fabric. The two pairs, upper and lower, of channels are arranged substantially at the same longitudinal height as the tunnel. In the area in which the two respective channels bifurcate from the storage tank, a deflector is provided, controlled by an actuator that, when actuated, closes one channel keeping the other open, or vice versa. [0005] From the point of view of operation, the fabric inside the tunnel is moved by the push or pull exerted by the air that impacts the fabric in an inclined manner from above and from below, i.e., by the horizontal pushing component of the air on the fabric. The fabric pulled by the air impacts against an impact structure and falls into the tank below. The deflectors of the upper and lower blower device are positioned so that the air is all conveyed in the channels oriented in a direction of the tunnel or all conveyed in the channels oriented in the opposite direction. The motion of the fabric is periodically reversed acting on the deflectors, so that each section of fabric can impact against the impact structures several times. The fabric is overfed to the tunnel. The alternating motion is overlapped by a slow feed movement the fabric so that a section of fabric, after a certain number of impacting cycles, is in any case located outside the tunnel and is ready for any further processing in a new station.

[0006] The air for pushing or pulling the fabric is recovered by a suction system that can be provided, for example, with suction areas at the ends of the tunnel (for example in front of the impact structures, which are appropriately perforated), or can (also) be provided with suction holes arranged on the top and/or on the bottom of the tunnel. Besides moving the fabric, the air also dries it.

[0007] The flows or jets of air are produced by an air movement system comprising, for example, one or more fans.

[0008] Although these machines have proved to operate optimally, they are still susceptible to improvements, for example, linked to flexibility of use and energy saving.

[0009] For example, to be able to vary the output pressure of the air from the channels (i.e., in the tunnel), and therefore vary the impact speed of the fabric against the impact structures, the number of revolutions of the fan must be varied. However, this also leads to an increase in air flow rate and electricity consumption, with the relevant costs deriving therefrom.

[0010] Moreover, in tunnels provided with a plurality of blower devices, the air passing through the tunnel in one direction tends to enter the channels that are not active (i.e., the channels isolated by the deflectors, hence which the air for pushing the fabric does not pass through), causing hydraulic losses and turbulence in the tunnel, to the detriment of its energy efficiency.

Summary

[0011] The aim of the present invention is to provide a pneumatic conveyor system for fabric in machines for processing fabric which solves the problems encountered in prior art systems.

[0012] In relation to this aim, an important object of the present invention is to produce a pneumatic conveyor system for fabric in machines for processing fabric that allows the pressure and/or the speed of the air for conveying the fabric to be varied.

[0013] Another important object of the present invention is to produce a pneumatic conveyor system for fabric in machines for processing fabric with which it is possible to limits losses in air flow and turbulence within this flow.

[0014] One more important object of the present invention is to provide a method for conveying a fabric with which it is possible to limit energy losses.

[0015] These and other objects, which will be more apparent below, are achieved with a pneumatic conveyor system for preferably damp fabric in machines for processing fabric, comprising a transit tunnel and at least one air blower device provided in the tunnel, comprising at least a first and a second channel, diverging from each other and inclined with respect to the direction of extension of said tunnel, which flow into the tunnel to convey air respectively according to an inclined direction converging in a first direction of feed of the fabric in the tunnel and according to an inclined direction converging in a second direction of feed of the fabric opposite said first direction, in order to produce a movement pushing on the fabric alternately in the two directions of convergence, so that when the first channel is active, i.e., the air passes through the first channel and not through the second channel, the fabric is moved in the first direction of feed, while when the second channel is active, i.e., the air passes through the second channel and not through the first channel (which is not active), the fabric is moved in the second direction of feed. The particularity of the invention lies in the fact that the conveyor system also comprises a variation device of the dimensions of the area of a section of the channels of said blower device, in order to adjust the air pressure delivered from these channels, obtaining a variation of the speed of the fabric in the tunnel.

[0016] Preferably, the variation device of the dimensions of the area of a section of the channels of the blower device comprises, for each channel, a closing body of the outlet port of the channel in the tunnel; this closing body is adapted to take a plurality of positions for blocking said outlet port, from an initial position with the outlet port open to a final position with the outlet port partly, or completely, blocked.

[0017] Plurality of positions for blocking is meant both as a discrete number of positions, for example predefined, for example obtained by means of a stepped movement between positions of the closing body, and a number of positions that are not predefined, given by a non-discrete movement (i.e., a movement that allows any position along the movement section of the closing body), or being able to implement a continuous movement of the closing body from the initial position to the final position.

[0018] Preferably, the closing body is a moving blade or bulkhead provided positioned at an end portion of a wall of the channel, so that the face of the bulkhead facing the inside of the channel defines an end portion of said channel and the free end of the bulkhead defines part of the edge of the outlet port of the channel in the tunnel. Therefore, the movement of the bulkhead from the initial position toward the final position causes a narrowing of the end portion of the tunnel and of the outlet port, i.e., a reduction of the area of the outlet port in the tunnel, or optionally complete closing of the outlet port.

[0019] Preferably, the moving bulkhead is hinged at an end portion of a wall of the channel, so that its movement between the initial position and the final position is a rotary movement.

[0020] In other embodiments, the bulkhead can, for example, move by translation, or roto-translation.

[0021] Advantageously, each said first and second channel is provided with a respective closing body. [0022] Preferably, the system comprising the blower device comprises at least a first said blower device arranged on the upper part of said tunnel, and at least a second said blower device arranged on the lower part of said tunnel; preferably, the outlet ports of respective channels of the two blower devices in the tunnel are provided in a same longitudinal position along the tunnel.

[0023] Preferably, the variation device comprises a mechanism for the simultaneous movement of the closing bodies of the first and second channel; preferably there is provided a single movement actuator and movement transmission members connected to this single actuator, adapted to simultaneously move the closing bodies of the first and second channel, i.e., to simultaneously move all the closing bodies present in the tunnel, based on the actuation of said actuator.

[0024] This solution is, for example, preferable when in the tunnel there is a single pair of blower devices having two overlapped pairs of first and second channels.

[0025] Preferably, the mechanism for simultaneous movement simultaneously moves of all the closing bodies of the correspondingly facing first and second blower device positioned on the upper and lower parts of said tunnel.

[0026] According to preferred embodiments, the system is provided with a device for closing the channels when they are not active and more preferably a device for closing the outlet ports in the tunnel when the channels are not active, so as to prevent the air passing through said tunnel from leaking into channels that are not active.

[0027] In other embodiments, the pneumatic system comprises a plurality of said blower devices provided on the upper part and a plurality provided on the lower part of the tunnel, to push the fabric in the desired direction both from above and from below, and wherein each closing body of the channels of said blower devices is adapted to take a plurality of blocking positions of the respective outlet port, from an initial position in which said outlet port is not blocked, to a final position with said outlet port completely blocked, or closed, and wherein, during pushing of the fabric by the air passing through said active channels, each variation device positions, in the channels that are not active, the respective closing bodies in said final closed position, so as to prevent the air passing through said tunnel from leaking into the channels that are not active. [0028] Therefore, in this situation, the closing bodies are subjected to a “one-off’ movement when it is necessary to adjust the width of the outlet port (and hence the pressure/speed of the air flow delivered from the tunnel), a movement to close the outlet port each time the related channel in which the closing body acts becomes a channel that is not active, and a movement to open the outlet port when the channel become active once again, i.e., the air flow passes through this channel.

[0029] Preferably, given a pair of correspondingly facing blower devices in said tunnel, the pneumatic system is provided with a first mechanism for moving, preferably simultaneously, the closing bodies of the first channels of the two upper and lower blower devices, and a second mechanism, independent from the first mechanism, for moving, preferably simultaneously, the closing bodies of the second channels of the two upper and lower blower devices, so as to be able to adjust the air flow delivered from both first or both second channels, and to be able to close the first or the second channels when not active to prevent air from leaking into them (and obviously to open them again when they require to be active); preferably there are provided respective actuation assemblies for said first and said second mechanism.

[0030] The term “independent” means that the mechanisms are actuated by different members to one another, so that in order to perform the movement of the closing bodies of two overlapped first channels and of two overlapped second channels of two overlapped blower devices, it is necessary to actuate two distinct mechanisms, one for each pair of overlapped channels. It is clear that the actuation of these mechanisms is coordinated in time to open/close the channels that are not active, at each reversal of the air flow in the tunnel by the electronic control unit of the machine.

[0031] For example, each actuation assembly comprises two actuators, for example arranged in series, a first actuator allowing adjustment of the position of the closing bodies to adjust the width of the outlet port (and hence the pressure/speed of the air flow delivered from the tunnel), which is only actuated when this adjustment is required, and a second actuator allowing closing and opening of the outlet port when the channels are not active/active.

[0032] According to preferred embodiments, the blower device comprises at least one flow diverter operating in at least two positions, a first position for closing said first channel to convey air into said second channel, and a second position for closing said second channel to convey air into said first channel. More preferably, the first and second channel converge in a duct that conveys the air from the air movement system, and this flow diverter acts in the area of intersection between first channel, second channel and duct.

[0033] In other embodiments, the diverter can be arranged in an intermediate, neutral, position, so as to simultaneously convey the same air flow for the two channels, thus creating two opposing pushes on the fabric, which can therefore remain stopped or slow down temporarily.

[0034] According to another aspect, the invention relates to a machine for processing a fabric, comprising

- a movement path for the fabric between two processing areas,

- chambers located upstream and downstream of at least one section of said path and inside which the fabric is adapted to enter according to the direction of movement to carry out a process,

- a pneumatic conveyor system for conveying the preferably damp fabric along said path according to one or more of the preferred embodiments illustrated above.

[0035] The machine, and the conveyor system of the fabric, are advantageously provided with an electronic control unit of the various components, to allow operation thereof.

[0036] Preferably, this machine is a machine for carrying out a softening and shrinking process for a fabric, for example a damp fabric. The machine can also process a dry fabric.

[0037] Preferably, the chambers are provided with respective impact structures located upstream and downstream of at least one section of said path and against which the fabric is adapted to impact according to the direction of movement to carry out a softening and shrinking process through impact. [0038] Preferably, the machine carries out a drying process of the fabric by means of the air flows in the tunnel.

[0039] According to another aspect, the invention relates to a method for moving a fabric that provides for pulling or pushing the fabric, by means of jets air above and below a fabric being processed, alternately toward opposed chambers into which the fabric is adapted to enter, the directions of said jets of air being inclined with respect to the horizontal so as to create a resulting horizontal pushing or pulling component of the air on the fabric that allows it to be moved, wherein said jets of air enter said tunnel from a plurality of channels with opposed inclinations, characterized in that said inclined channels have respective closing bodies of the outlet ports of the channels in the tunnel, movable with respect to the walls of the channels, said method providing for adjusting the position of said closing bodies in said channels in order to vary the dimensions of the outlet port, thereby adjusting the pressure of the jets of air delivered from said channels.

[0040] Preferably, a plurality of said channels are provided with the same inclination, i.e., a plurality inclined in one direction and a plurality inclined in the opposite direction, both on the upper portion of the tunnel and on the lower portion of the tunnel; when the jets of air are fed from the channels inclined in a first direction, i.e., push the fabric in a first direction, the outlet ports of the other channels inclined in the second direction (i.e. the channels that are not active, those through which air does not pass) are closed, and vice versa.

[0041] Preferably, this method is obtained with a pneumatic conveyor system according to one or more of the preferred embodiments illustrated above.

Brief description of the drawings

[0042] The invention will be better understood by following the description and accompanying drawings, which illustrate a non-limiting example of embodiment of the invention. More in particular:

[0043] Fig. 1 represents a schematic view of a machine with a pneumatic conveyor system of fabric, according to the invention, [0044] Fig. 2 represents a schematic view of a portion of the conveyor system of fabric of Fig. 1;

[0045] Fig. 3 represents a schematic view of a machine with a conveyor system of fabric, according to the invention, varying with respect to Fig. 1;

[0046] Fig. 4 represents a schematic view of a portion of the conveyor system of fabric of Fig. 3.

Detailed description of embodiments

[0047] With reference to the previously cited figures, a schematic diagram of the machine according to the invention is indicated as a whole with 10. Hereinafter it is described only in its fundamental components. The figures show a machine configured to process a fabric (preferably damp or wet, or also a not damp fabric) in width, i.e. laid out according to its cross direction. Likewise, the machine according to the invention can be configured to process a fabric in rope form. The machine essentially comprises a preferably horizontal path 11, at least partly pressurized, along which a fabric T moves, and a two-way pneumatic conveyor system 100, according to the invention, fed by a pneumatic circuit 13, and an optional further pneumatic air suction and recirculation circuit (not shown in the figures). The conveyor system 100 is provided with a tunnel 15 that defines at least a part of the path of the fabric.

[0048] The machine, and the pneumatic conveyor system are managed by an electronic control unit M.

[0049] Two impact structures 16 and 17, for example in the form of grills, against which the fabric is adapted to impact, are provided upstream and downstream of the tunnel 15, for example in respective chambers, as better explained below.

[0050] In the preferred embodiment, the machine according to the invention advantageously comprises at the ends of the path 11, under the impact structures 16 and 17, preferably in said chambers, respectively a first processing tank 18 and a second processing tank 19, in which an accumulation of fabric being processed alternately forms. [0051] Besides moving the fabric, the air flows of the pneumatic conveyor system 100 allow controlled drying of the fabric.

[0052] In Figs. 1 and 2, the pneumatic conveyor system 100 directs pressurized air through two blower devices 20 and 21 located respectively in the upper and lower part of the tunnel, substantially in the same longitudinal position along the tunnel 15 in which the fabric is pneumatically conveyed. Each blower device 20-21 has a feed duct 20A-21 A or air storage tank that ends with a first and a second channel 20B’-21B’ and 20B”-21B”, diverging from each other and inclined with respect to the direction of longitudinal extension of said tunnel 15, i.e., the direction of movement of the fabric.

[0053] Each channel 20B’, 21B’, 20B” and 21B” has a respective outlet port 25 in the tunnel 15.

[0054] In this example, each blower device 20-21 is provided, in a known way, with a flow diverter 20C-21C in the form of a hinged plate, for example positioned in the area in which the duct/air storage tank 20A-21 A bifurcates into the two channels 20B’- 21B’ and 20B”-21B” and which is capable of selectively closing one of the two channels, forcing all of the air flow toward the opposite diverging channel. In this way, the upper and lower blower devices 20 and 21 convey air, in a manner coordinated with one another, according to inclined directions converging in a first direction of feed of the fabric toward the second impact structure 17 and a second position in which the upper and lower blower devices 20 and 21 convey air in a manner coordinated with one another according to inclined directions converging in a second direction of feed of the fabric opposite the first direction toward the first impact structure 16.

[0055] The air flows converging in an inclined direction on the fabric from above and from below coming from the channels 20B’-21B’ or 20B”-21B” impact the fabric. These flows are substantially balanced both in terms of flow rate and in terms of incidence and therefore the vertical components of the air push on the fabric cancel one another out, while the horizontal components are added to one another, pushing/pulling the fabric along the path 11 toward the outlet port of the tunnel to impact on a corresponding impact structure.

[0056] From an operational point of view, the fabric is moved pulled by the air delivered from the first channels (which are thus “active” channels) of the blower devices 20B”-21B” (coming from the compressor/fan 26 through the storage tanks 20 A, 20B), from a first tank 18 toward the second tank 19, impacting on a respective impact structure 17. After a given amount of time, the air flow is conveyed toward the second channels 20B’-21B’ (which until this conveying were not active, i.e., without air for pulling the fabric passing through them) of the blower devices 20-21, which in this way become active channels, thereby reversing the direction of the push and consequently of movement of the fabric, which is pulled from the second tank 19 toward the first tank 18, impacting on the opposite structure 16. As a whole, there is in any case a forward movement of the fabric along the path (for example toward the second tank 19) so that all of the fabric can be processed.

[0057] Characteristically, the conveyor system 100 comprises a variation device 30 of the dimensions of the area of a section of the channels of the blower device, in order to adjust the air pressure delivered from these channels, obtaining a variation of the speed of the fabric in the tunnel.

[0058] Preferably, the variation device 30 of the dimensions of the area of a section of the channels comprises, for each channel, a closing body 31 of the respective outlet port 25 in the tunnel.

[0059] This closing body 31 can take a plurality of positions for blocking this outlet port 25, from an initial position with the outlet port open, to a final position with the outlet port partly blocked.

[0060] In these examples, each closing body 31 is a moving bulkhead or blade (hereinafter indicated with the same number as the closing body, and also with the specific numbers 31.1, 31.2, 31.3, 31.4, when it is necessary to distinguish them from one another) hinged to an end portion of a wall of the respective channel, so that the face of the bulkhead facing the inside of the channel defines an end portion of said channel and the free end 31 A of the bulkhead 31 defines part of the edge of the outlet port 25 of the channel in the tunnel.

[0061] Therefore, moving the bulkhead 31 from the initial position toward the final position causes a narrowing of the end portion of the tunnel and of the outlet port 25, i.e., a reduction of the area of the outlet port in the tunnel. [0062] In the case of Fig. 1, the conveyor system 100 is provided with a single pair of blower devices arranged on the upper part and lower part of the tunnel.

[0063] In this case, the variation device 30 comprises a mechanism 35 for the simultaneous movement of all the bulkheads 31 of the channels, which comprises a single movement actuator 36 and movement transmission members kinematically connected to this actuator 36, adapted to simultaneously move the bulkheads 31, thus allowing, with a single actuation of the actuator 36, adjustment of the dimensions of all the outlet ports 25 of the channels 20B’, 20B”, 21B’, 21B”) in the tunnel 11. Advantageously, these variations will be the same for each outlet port 25, it being preferable for the outlet ports all to have the same dimensions.

[0064] In this example, the actuator 36 is an electric motor that has an output shaft forming a worm screw 36.1. On this worm screw 36.1 there is arranged is a lead screw that carries jointly therewith a slider 36.2 arranged slidably, and with rotatable coupling, inside a slot 37.1 defined at one end of a first lever body 37. This latter is integral with a first bulkhead 31.1 and therefore is hinged to the tunnel at the same rotation axis as the bulkhead (bulkhead and lever body rotate jointly on the hinge of the bulkhead). A rotation of the worm screw 36.1 causes the lead screw with the slider 36.2 to travel along it, pushing on the slot 37, forcing the lever body 37 to rotate around the hinge with axis K, with consequent rotation of the bulkhead 31.1 around the same axis, for example from an initial position in which the area of the outlet port is at its maximum dimensions, to a position close to the opposite part of the channel with respect to the wall where the hinge with axis K is positioned, thereby reducing the section of the respective outlet port 25.

[0065] Advantageously, from the lever body 37 there extends an appendage, in which there is produced a first guide 37.2 inside which there is slidably and rotatably arranged a cylinder 38.1, provided at the end with a first rocker arm 38, the opposite end of which is integral with a second bulkhead 31.2 facing the first bulkhead 31.1, which defines the outlet port of the facing channel.

[0066] Therefore, the rotary movement of the lever body 37 causes the pushing of guide 37.2 on the cylinder 38.1, which rotates the first rocker arm 38 and therefore the second bulkhead 31.2, by a rotation angle equal to the rotation angle of the first bulkhead 31.1 (but in the opposite direction).

[0067] Moreover, the opposite end of the first lever body 37 has a second guide 37.3 for a second cylinder 39.1 rotatably and slidably arranged therein and constrained at the end of a second lever body 39, in turn jointly constrained to the rotation axis of a third bulkhead 31.3; therefore, this second lever body 39 is hinged to the tunnel at the same rotation axis H of the third bulkhead (third bulkhead and second lever body rotate jointly on the hinge with axis H of the third bulkhead).

[0068] Therefore, the rotation of the end of the first lever body 37 around K also causes a push by the second guide 37.3 on the second cylinder 39.1, with consequent rotation of the second lever body 39 and of the third bulkhead 31.3 by a rotation angle equal to the rotation angle of the first bulkhead 31.1 (but in the opposite direction).

[0069] Moreover, the second lever body 39 is provided with an appendage with a third guide 39.2 in which there is slidably and rotatably arranged a third cylinder 40.1 constrained at the end of a second rocker arm 40, in turn jointly constrained to the rotation axis of a fourth bulkhead 31.4; therefore, this second rocker arm 40 is hinged to the tunnel at the same rotation axis B of the fourth bulkhead (fourth bulkhead and second rocker arm rotate jointly on the hinge with axis H of the third bulkhead).

[0070] Therefore, the rotation of the end of the second lever body 39 around H also causes a pushing by the third guide 39.2 on the third cylinder 40.1, with consequent rotation of the second rocker arm 40 and of the fourth bulkhead 31.4 by a rotation angle equal to the rotation angle of the first bulkhead 37.1.

[0071] Fig. 3 shows the case in which the conveyor system 100 is provided with a plurality of blower devices (two in the specific example) 20 in the upper part of the tunnel and an equivalent plurality of blower devices 21 in the lower part of the tunnel.

[0072] In this case, to prevent the air passing through the tunnel from entering channels that are not active, the system is provided with a device for closing the channels when they are not active, described below.

[0073] In particular, to close these channels, each closing body 31 of the channels 20B’, 20B”, 21B’, 21B” of the blower devices 20-21 is adapted take a plurality of blocfang positions of the respective outlet port 25, from an initial position in which the outlet port is not blocked, corresponding to maximum opening of the channels, to a final position with the outlet port 25 completely blocked, or closed. This final position is only taken when the channels are not active, i.e., when the fabric is pushed by the air passing through the active channels, which are left open or partly open by the respective closing bodies.

[0074] Therefore, in this situation, the closing bodies 31 are subjected to a “one-off’ movement when it is necessary to adjust the width of the outlet port 25 (and hence the pressure/ speed of the air flow delivered from the tunnel 11), a movement to close the outlet port 25 each time the related channel 20B’, 20B”, 21B’, 21B” in which the closing body 31 acts becomes a channel that is not active, and a movement to open the outlet port 25 when the channel becomes active again, i.e., the air flow passes through this channel.

[0075] More in particular, to carry out both closing and adjustment of the position of the closing bodies 31, the pneumatic system is provided with a first mechanism 135 for simultaneously moving the bulkheads 31.3, 31.4 of the first channels 20B’, 21B’ of the two upper and lower blower devices 20-21, and a second mechanism 135 A, distinct and independent from the first mechanism 135, but functionally coordinated therewith, for simultaneously moving the bulkheads 31.1, 31.2 of the second channels 20B”, 2 IB” of the two upper and lower blower devices.

[0076] In this way, it is possible to adjust the air flow delivered from both first or both second channels 20B’, 21B’, 20B”, 21B”, and to be able to close the first or the second channels when not active to prevent air from leaking into them (and obviously to open them again when they require to be active).

[0077] Each first and second mechanism 135, 135 A is provided with respective actuation assemblies 136. For example, each actuation assembly comprises two actuators, for example arranged in series, and more in particular a first actuator 136’ that allows adjustment of the position of the closing bodies 31 to adjust the width of the outlet port 25 (and hence the pressure/speed of the air flow delivered from the tunnel), which is only actuated when this adjustment is required, and a second actuator 136” which allows the outlet port 25 to be closed or opened when the channels are not active/active.

[0078] For example, the first actuator 136’ is an electric motor with an output shaft forming a worm screw 136.1, on which there is rotatably mounted a lead screw 136.2 on which there is hinged the second actuator 136”, for example a side shift cylinder. Advantageously, the hinge axis lies on a plane parallel to the plane on which the hinge axes of the bulkheads to the tunnel lie.

[0079] At the end of the actuation rod of the side shift cylinder 136” there is hinged a lever body 137. This latter is integral with the closing body 31 (bulkhead) and therefore is hinged to the tunnel at the same rotation axis of the bulkhead (bulkhead and lever body rotate jointly on the hinge of the bulkhead). A rotation of the worm screw 136.1 causes the rotation there along of the lead screw 136.2 and the side shift cylinder 136’ ’ (not active in this phase, i.e. in practice forms a stem hinged at the ends), forcing the lever body 137 to rotate about its hinge axis to the tunnel 11, with consequent rotation about the same axis of the bulkhead, thus adjusting the position of the bulkhead, i.e., adjustment of the area of the outlet port 25 of the channel 20B”, 21B”, 20B’, 21B’, in the tunnel 11. This adjustment takes place only when it is necessary to adjust the pressure of the air flow in the tunnel.

[0080] Differently, actuation of the side shift cylinder 136” allows the lever body 137 to rotate from the open position to a position closing the outlet port 25 in the tunnel 11 (in Fig. 4, closing of the first channels 20B’, 21B’), and is activated at each reversal of the air flow, i.e., when the respective channel is excluded from the air flow that conveys the fabric and becomes a channel that is not active. In this situation, to prevent the air flow in the tunnel from flowing back through the channel that is not active, the moving bulkhead 31 of the channel is closed activating the side shift cylinder 136”.

[0081] Advantageously, on the part of the tunnel opposite the one with the hinge of the moving bulkhead 31 to the tunnel, there is provided a seat for a sealing gasket 140 of the end of the bulkhead, when closed.

[0082] Advantageously, from the lever body 137 there extends an appendage in which there is produced a first guide 137.2, inside which there is slidably and rotatably arranged a cylinder 138.1 provided at the end with a rocker arm 138, the opposite end of which is integral with a second bulkhead facing the upper bulkhead, which defines the outlet port 24 of the facing channel.

[0083] Therefore, the rotary movement of the lever body 137 causes the guide 137.1 to push on the cylinder 138.1, which rotates the rocker arm 138 and therefore the respective bulkhead, by a rotation angle equal to the rotation angle of the facing bulkhead (but in the opposite direction).

[0084] In practice, the method for moving the fabric associated with the conveyor system described allows pulling or pushing of the fabric T, by means of jets of air f above and below the fabric being processed, inside the tunnel alternately toward opposed chambers inside which the fabric is adapted to enter.

[0085] The directions of the jets of air are inclined with respect to the horizontal so as to create a resulting horizontal pushing or pulling component of the air on the fabric that allows it to be moved.

[0086] The jets of air enter the tunnel from the plurality of inclined channels, which are provided with respective closing bodies of the outlet ports of the channels in the tunnel, movable with respect to the walls of the channels, for example rotatable blades or bulkheads.

[0087] It is possible to adjust the position of the closing bodies in the channels in order to vary the dimensions of the outlet port, thereby adjusting the pressure of the jets of air delivered from the channels.

[0088] A plurality of channels with the same inclination are provided, i.e., a plurality inclined in one direction and a plurality of channels inclined in the opposite direction, both in the upper portion of the tunnel and in the lower portion of the tunnel.

[0089] When the jets of air are fed from the channels inclined in a first direction, i.e., when the jets of air push the fabric in a first direction, the outlet ports of the other channels inclined in the second direction (i.e., the channels that are not active, those through which air does not pass) are closed by closing bodies, and vice versa.

[0090] It is understood that what is illustrated above only represents possible nonlimiting embodiments of the invention, which can vary in forms and arrangements without departing from the scope of the concept on which the invention is based. Any reference numbers in the appended claims are provided for the sole purpose of facilitating the reading thereof in the light of the description above and of the accompanying drawings and do not in any way limit the scope of protection thereof.