FR2658538A1 - DEVICE FOR THE PNEUMATIC POWER SUPPLY OF AT LEAST ONE FIBER PROCESSING MACHINE, FOR EXAMPLE CARDING. - Google Patents

Abstract

This device comprises a fiber transport duct between an upstream processing machine, an opener finisher for example, and one or more processing machines receiving fibers. In order to obtain a technologically optimal filling with fibers of the different chimneys (4a-4d) feeding the cards (6) from the transport duct (3), as well as to allow an extension of the working ranges, a bypass duct d air (9) is connected to the common transport duct (3) and the air flow in this bypass duct (9) is adjustable according to the filling level of the chimneys (4a-4d) and / or according to the number of chimneys. The invention is particularly applicable to cotton spinning.

Description

The invention relates to a device for the pneumatic supply of

  less a fiber processing machine, for example a card, by means of hoppers or filling funnels preceding the various fiber-processing machines and which are connected to a common pneumatic conveying conduit, which is connected through a fan for transporting fibrous material to an upstream fiber processing machine, a finishing machine operator

example.

  In a flock loading system or other pneumatic conveying and / or filling systems, the operation may be adversely affected when the air flows of fiber-supplying machines (for example, fining machines) and Fiber-receiving machines (flake feed chimneys for cards for example) are not identical and conform to optimal operation In a known device, disadvantages arise when the airflows or pressures undergo relatively large changes in time Air leakage due to leaks in the transport duct may

  also affect the working conditions General-

  the ratio of the different air flows is established once and for all for a given work point, for example in order to obtain a p 2 counter pressure at a

  given point of the transport duct In case of change

  pressure, for example due to varying filling levels in the chimneys or changes in the number of consumers (eg cards), throttling of the air flow in one part of the system may result in too much increase in the air flow in another part of the system Thus, the pressure P 2 technologically necessary for optimal filling can not

to be reached or maintained.

  In view of this state of the art, the object of the invention is to create a device of the type indicated at the beginning, which avoids the disadvantages mentioned, in particular authorizes a technologically filling

  optimal loading system and allows for an exten-

work areas.

  According to the invention, this result is obtained by

  a device, as defined at the beginning, which is

  in that it comprises an air bypass duct connected to the transport duct, and that the air flow in the air bypass duct is adjustable in

  function of the mass of fibers contained in the

  filling and / or depending on the number of

filling chimneys.

  With the device according to the invention, the air flow in a large part of the transport duct can remain constant and the desired pressure P 2 at the determined point of the transport duct can be obtained or approximated further. This greater constancy of the pressure has the advantage that the filling of chimneys (or a chimney if it is a matter of loading a single card) is closer to the optimal fiber filling In addition, it thus becomes possible to work in unrealizable production ranges without the

device according to the invention.

  It is advantageous that the air flows in the air bypass duct and the transport duct

  downstream of the connection point of the

  and / or in the filling chimneys be

  measurable directly or indirectly It is also

  Advantageously, the air pressure in the transport duct and / or the chimneys is measurable. The bypass duct advantageously comprises a device for adjusting the airflow, for example in the form of a damper. bypass duct is connected to a suction source, by

  example on a filter to which an aspira-

  This duct can also communicate with the outside air. It is advantageous to provide a control and / or regulation device which is connected to the measuring elements for the flow of air in the transport duct and / or the air pressure, as well as the regulator for adjusting the air flow in the duct: 0 bypass It is preferable that the control and / or regulation device is connected to an organ

  measuring the air flow upstream of the connection point

  of the bypass duct and / or downstream of the connection point of the bypass duct to the transport duct, as well as to a regulating member for adjusting the air flow in the bypass duct. or adjust the airflow rate in the bypass duct proportionally to the airflow rate in the portion of the transport duct located downstream of the connection point of the bypass duct It is preferable that a data memory for values of The setpoint is coordinated with the control and / or control unit, which may be constituted in particular by a microcomputer. Other features of the invention provide that a setpoint generator is coordinated with the control unit. and / or regulating and is in connection with the air flow measuring member in the aforesaid part of the transport conduit. This measuring member is preferably placed between the connection point of the bypass duct

and the filling chimneys.

  In an improved embodiment, from the technical point of view of operation, the air flows in the bypass duct and in the downstream part of the transport duct are proportionally adjusted. As a reference value, the regulator receives in this case a signal generated as a function of the air flow in the part of the transport duct located downstream of the connection point of the bypass duct In this way, a higher pressure is obtained even at the predetermined point mentioned previously in the transport duct. advantageous to ensure

  regulation, the prior fixing of the con-

  sign and memorization of these values using a system articulated around a microprocessor and ensuring

  simultaneously control of the machines or the installation

  lation. Other features and benefits of

  the invention will become clearer from the description of

  following examples of non-limited

  as well as the attached drawings, in which:

  FIG. 1 is a diagrammatic representation

  of a device according to the invention on a conduit

  feeding and distribution of flakes leading to

  carding systems (fireplaces); Figure 2 is a schematic side view of the device according to the invention with the air bypass duct; Figure 3 shows in particular the measuring member and the air flow adjusting member in the bypass duct of the device; FIG. 4 shows, in particular, devices for measuring the flow rates of air in the pneumatic transport duct and in the bypass duct; and FIG. 5 shows such a device with, in addition, a measuring member for the air pressure p 2 in

the transport pipe.

  Figure 1 is an elevation of a fluff feed device A transport blower 1 is connected by its suction side to a finishing machine 2 The discharge pipe of the blower

  1 is connected to a supply and distribution duct

  3 which passes over a feeder (loading system) 4 of cards and which are connected to the filling funnels 4 ad An electronic pressure sensor 5 is mounted on the distribution duct 3 above the first chimney 4 a for the measurement of the pressure P 2 which has been mentioned previously The transport fan 1 sucks up the fibrous material

  opened since the last threshing point of the

  2) in this example and transports the material through a conveyance air stream through the feed and delivery line 3 to the filling funnels 4a to 4d of the card feeders 4 connected at the entrance of the mixture of flakes and air in the chimneys 4 ad,

  the air used for transport, escapes through the ori-

  18a-18b (see FIG. 2), while the flakes accumulate in the chimneys 4a to 4a, forming columns of fibrous material. When these columns begin to block the outlets of 18 air, the pressure P 2, measured at the point indiaué in Figure 2 of the supply duct and distribution 3, rises This rise in pressure continues as the chimneys 4 to 4 d are filled more and the pressure reaches its highest point when the air outlet openings 18 a-18 b of all the chimneys 4 a to 4 b are completely covered. The values of the pressure P 2 determined with the aid of the sensor 5 at the beginning of the 3, above the first stack 4a, are used to adjust the transfer of material from the opening 2 to the transport fan 1 The latter

  is in continuous operation to maintain the conditions

  desired pressure levels in the duct 3

  According to the requirements of the cards 6, the fibrous material is extracted from the chimneys 4a to 4d by call rollers 17a, 17b (see FIG. 2). Thus, the columns of material in the chimneys 4a to 4d are The pressure P 2 decreases accordingly, so that the material flow of the finishing machine 2 is increased. fibrous material to the chimneys 4 to 4 d The electronic pressure sensor 5 is connected for this purpose through a regulator 7 to an electric motor 8 whose speed is continuously adjustable and which drives an opener cylinder in the finishing machine The pressure sensor 5 can however also act on additional servo-control elements for the variation of the

beginning of the flakes to transport.

  On the transport duct 3, is connected a

  air bypass duct 9 which leads to a filter 10.

  The bypass duct 9 contains a pivoting damper 11 which makes it possible to open or close more or less the section of this duct and thus to adjust the air flow M 3 in the duct 9. The damper 11 is controlled by a

  pneumatic adjusting member 12 connected to the regulator 7.

  In FIG. 2, the arrow M 1 denotes the air flow rate in the upstream portion of the transport duct 3, that is to say the portion between the fan 1 and the connection point 9 a of the bypass duct. The arrow M 2 denotes the air flow in the downstream part of the transport duct, between the connection point 9a of the bypass duct 9 and the chimneys 4a to 4d (see FIG. 1). designates the flow of air in the bypass duct 9 The arrows indicate the flow directions of the air corresponding to the different flow rates Mi, M 2 and M 3 * The arrow A designates generally the mixture of flakes of fibers and of air in the transport duct 3, while 4 'denotes the column of flakes in the chimney 4a It should be noted that the connection point 9a of the bypass duct is formed by holes smaller than the flakes

fiber.

  According to FIG. 3, the air bypass duct 9 is provided with a measuring member 13 for the flow of air M 3, which member is connected, through a regulator 7 provided with a value generator setpoint 7a, with a regulator (servo) 14 for the damper 11 This can rotate in the direction of the arrows B and C The measuring member 13a, as well as the measuring lines 13b and 13c coordinates, are

provided upstream of register 11.

  According to FIG. 4, the conveying conduit 3 is provided, downstream of the connection point 9 a of the bypass duct 9, with a measuring member 15 for the flow rate

  of air M 2 'to which are coordinated canalisa-

  15 b and 15 c which are connected with the

  setpoint generator 7a of the controller 7.

  According to FIG. 5, the conveying duct 3 is provided with the measuring member 15 for the air flow M 2 and the sensor 5 intended for the measurement of the pressure P 2 and in which is coordinated a pressure converter 5 a , itself connected to a control and regulating device 7 in the form of a microcomputer for example to the latter are further connected the adjustable drive motor 1a for the fan 1, the drive motor 8 for the finisher 2, the measuring member 13 for the air flow M 3, the adjusting or servo-controlling member 14 for the damper 11 and the adjustable driving motor 16 for the rollers

  17a, 17b of the chimney 4 a.

  In addition, it is possible to provide a measuring member (not shown) for the air flow M in the part

  downstream of the transport duct, which would also be

connected to the regulator 7.

  As a loading device 4, it is possible to use a card feeder Tr Utzschler EXACTAFEED FBK. In this case, it is possible to connect the adjustable drive motor to the regulator 7.

  feeding rollers at the lower end of the

mined reserve at the top.

Claims (15)

  1 Device for the pneumatic supply of at least one fiber-processing machine, for example a card, by means of hoppers or filling funnels preceding the various fiber-processing machines and which are connected to a common conduit of pneumatic transport, which is connected through a fibrous material transport fan to a fiber-processing machine installed upstream, a finishing machine for example, characterized in that it comprises an air bypass duct (9). ) connected to the transport duct (3), and that the air flow (M 3) in the air bypass duct (9) is   adjustable according to the mass of fibers (4 ')   in the filling stacks (4, 4 a to 4 d) and / or depending on the number of filling stacks (4, 4 to 4 d).   2 Device according to claim 1, characterized   in that the air flow (M 2) in the transport pipe and / or the filling pipes (4) is   measurable directly or indirectly.   3 Device according to claim 1 or 2, characterized in that the air pressure (p 2) in the   transport duct (3) and / or chimneys to fill wise (4) is measurable.   4 Device according to any one of the   1 to 3, characterized in that the air flow (M 3) in the duct of the air ducts (9) is   measurable directly or indirectly.   Device according to any one of the   1 to 4, characterized in that a device for adjusting the air flow (M 3), a damper (11) for example, is incorporated in the bypass duct of air (9).   6 Device according to any one of the   1 to 5, characterized in that the conduit of   air diversion (9) is connected to a vacuum source   ration, for example on a filter (10) to which is applied an aspiration.   7 Device according to any one of the   1 to 6, characterized in that it comprises a control and / or regulation device (7) connected to the measuring elements (15 or 5) for the air flow (M 2).   and / or the air pressure (P 2) in the transmission conduit   port and the adjusting member (11; 14) for adjusting the air flow (M 3) in the air bypass duct (9).   8 Device according to claim 7, characterized   in that the control and / or regulating device   (7) is connected to the air flow measuring element (M 1) in the transport pipe (3) upstream of the connection point (9 a) of the air bypass pipe (9). and / or for the air flow (M 2) in the conveying pipe (3) downstream of this connection point (9 a), as well as to the adjusting member (11;   adjust the air flow (M 43) in the air (9).   9 Device according to any one of the   1 to 8, characterized in that the air flow (M 3) in the air bypass duct (9) is adjusted or adjusted proportionally to the air flow rate (M 2) in the downstream transport duct the connection point   (9a) of the air bypass duct (9).   Device according to any one of the   6 to 9, characterized in that a data memory for set values is coordinated with   the control and / or regulation apparatus (7).   11 Device according to any one of the   6 to 10, characterized in that the apparatus for   control and / or regulation (7) is a micro-ordination tor. he   12 Device according to any one of the   6 to 11, characterized in that a setpoint generator (7 a) is coordinated to the control and / or regulation.   13 Apparatus according to Claim 12, characterized in that the setpoint generator (7a) is connected with the measuring element for the air flow (M 2) in the transport pipe (3) in   downstream of the connection point (9 a) of the air supply (9).   14 Apparatus according to any one of the   1 to 13, characterized in that the measuring member (15) for the air flow (M 2) in the transport pipe downstream of the connection point (9 a) of the air bypass duct ( 9) is placed between this connection point (9a) and the filling funnels (4).   Device according to any one of the   1 to 14, characterized in that the connection point (9a) of the air bypass duct (9) has smaller passage apertures. as fiber flakes.   16 Apparatus according to any one of the   1 to 15, characterized in that the air bypass duct (9) communicates with the outside atmosphere.