Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B43/00—Machines, pumps, or pumping installations having flexible working members
  • F04B43/08—Machines, pumps, or pumping installations having flexible working members having tubular flexible members
  • F04B43/082—Machines, pumps, or pumping installations having flexible working members having tubular flexible members the tubular flexible member being pressed against a wall by a number of elements, each having an alternating movement in a direction perpendicular to the axes of the tubular member and each having its own driving mechanism
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
  • B65G53/00—Conveying materials in bulk through troughs, pipes or tubes by floating the materials or by flow of gas, liquid or foam
  • B65G53/32—Conveying concrete, e.g. for distributing same at building sites
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
  • B65G53/00—Conveying materials in bulk through troughs, pipes or tubes by floating the materials or by flow of gas, liquid or foam
  • B65G53/34—Details
  • B65G53/40—Feeding or discharging devices
  • B65G53/46—Gates or sluices, e.g. rotary wheels
  • B65G53/4675—Gates or sluices, e.g. rotary wheels with flexible wall parts, e.g. peristaltic devices

Definitions

• the present invention relates to a device for transporting a material based on particles or grains such as concrete, device which comprises a flexible conduit having an upstream end connected to material supply means and a downstream end, means for crushing this conduit in a clocked manner and means for injecting compressed air into the conduit capable of being opened and closed in a clocked manner.
• a device of this type is used, for example, to transport concrete made up of a mixture of cement and aggregates between a feed hopper and a concrete spraying assembly comprising a spray lance.
• This device can be used for the so-called dry projection technique, in which the mixture of material is transported in the dry state in the pipe and is only humidified near the outlet of the lance, or the so-called projection technique. by wet diluted flow, in which the concrete mixture is already humidified before entering the pipe.
• a device of this type can also be used to transport materials other than concrete, for example food materials based on grains or granules, such as wheat.
• European patent n ° 0 588 737 discloses a device of this type in which the means for crushing the conduit comprise crushing protuberances arranged on a movable assembly, each of these protuberances moving in turn on the conduit so as to '' crush to push downstream the material while creating a suction immediately upstream of the protuberance to promote the entry of the material into the conduit.
• Compressed air is used to regulate the transport of the product and it is injected into the duct when the latter is no longer or practically no longer crushed by a protuberance.
• the known device also comprises a compression element which closes the duct upstream of the pressurized air inlet. , during the entire air injection sequence.
• this known device when a first protrusion overcomes the duct, crushing which occurs substantially at the level of the air inlet under pressure and downstream of the compression element, the air supply under pressure is closed, while the compression element is open, and the protuberance moves on the duct so as to discharge the air-material mixture towards the outlet of this duct while allowing the filling of said duct upstream. Then, when this first protuberance reaches in a region of the conduit in which it practically ceases to crush the latter, and while the second protuberance has not yet arrived in a situation in which it begins to crush the conduit, the compression element is closed and one opens the pressurized air supply so as to discharge the material towards the outlet. Then, substantially when the second protrusion reaches the situation in which it begins to crush the duct, the air supply is closed and then the compression element is opened so as to allow the material to feed the duct.
• the compression element which is closed during the injection of compressed air is arranged upstream of the zone that the protrusions come to crush first during their movement along the duct. It is not possible to place this compression element in the immediate vicinity of this contact zone, a slight distance being necessary to allow the protuberances to approach during their movement cycle. Consequently, when a protrusion comes to crush the duct, it traps pressurized air in the portion of the duct situated between the compression element and the crushing zone. Thus, when the compression element is opened to allow material to be supplied to the duct, the pocket of pressurized air located in this portion of the pipe expands, the air tending to escape towards the upstream of the conduit.
• the object of the invention is to remedy the aforementioned drawbacks by proposing an improved device with a view to increasing the life of the conduits and, above all, eliminating or at least considerably limiting the discharge of dust under the effect of the pressurized air exhaust.
• the means for crushing the conduit comprise a first crushing member and a second crushing member located downstream of the first crushing member in the direction of transport of the material, each crushing member being movable transversely to the conduit between a relaxation position and a crushing position
• the device comprises a delivery member, located between said first and second crushing members and capable of being moved transversely to the conduit between a position inactive and an active position in which it cooperates with the duct by substantially flattening the latter, to the fact that the air injection means open into a region of the duct situated between the first and second crushing members, in the vicinity of said first crushing device, and the fact that the device includes means for timing the injection of compressed air and the movements of the crushing members and the delivery member, according to successive cycles comprising the following phases:
• the crushing and delivery members which exert significant stresses on the conduit, are movable transversely to this conduit without moving along the latter, which limits the deterioration of the conduit.
• the duct is closed in its upstream region by the first crushing member and, at least towards the end of the air injection phase, the discharge member occupies its active position (it flattens the duct). So even if air is trapped in the duct under this discharge member when the second crushing member is placed in its crushing position before a new filling phase begins, it can only be a very small amount of air.
• the delivery device As soon as the delivery device changes from its active position to its inactive position, it will create a vacuum which will allow this possible small amount of air to relax and prevent it from evacuating upstream. In addition, this depression will suck the material from the hopper towards the conduit, facilitating and accelerating the filling of the latter.
• the indication that the delivery member substantially flattens the duct in its active position means that, in this position, the duct is practically shaped as a flat element, the two facing internal faces of which are in contact or, at least, extremely close to each other.
• the delivery member may not, however, strongly press these two internal faces against each other, in order to reduce the stresses on the duct.
• the means for timing the injection of compressed air and the movements of the crushing members and of the delivery member are further able to control, after the delivery phase of each cycle, a decompression phase in which the first and second crushing members are in the crushing position, the air injection means are closed and the delivery member is controlled from the active position to the inactive position.
• the device comprises means for adjusting the relaxation position of the first crushing member.
• the device comprises means for adjusting the clocking frequency of the cycles (number of cycles per unit of time) in order to vary the transport rate of the material and to adapt it to the work to be performed.
• FIG. 1 is a schematic sectional view of a device according to the invention
• FIG. 2A to 2F illustrate the operating cycle of the device of the invention
• FIG. 3 and 4 are two schematic views in cross section, corresponding respectively to the lines III-III and IN-IN of Figure 1 and respectively illustrating an alternative embodiment relating to the first crushing member and a variant relating to the delivery member, and
• Figure 5 is a view similar to Figure 1 showing an alternative embodiment.
• the device designated by the general reference 10 in FIG. 1 is used to transport a material based on particles such as concrete between a hopper 12 and a spray lance 14 situated at the end of a transport pipe 16.
• the device comprising a flexible pipe 18 is connected to the feed hopper 12 by its upstream end 18A and to the transport pipe 16 by its downstream end 18B.
• the upstream and downstream are identified with respect to the direction of transport of the material from the hopper 12 to the lance 14.
• the device 10 also includes a first crushing member 20 and a second crushing member 22 which is located downstream of the first.
• the two crushing members are movable transversely to the conduit 18 between a relaxation position and a crushing position.
• the first crushing member 20 occupies its relaxed position, that is to say that it does not crush the conduit 18, but leaves a passage for the material contained in the hopper 12, while the second crushing member 22 is shown in its crushing position, in which it closes the duct tightly and Therefore prevents the passage of the air-material mixture downstream and upstream from its position.
• the device also includes a delivery member 24 which is located between the first and second crushing members 20 and 22. Like the latter, it is capable of being moved transversely to the conduit.
• the delivery member 24 is shown in its inactive position, in which it is not or practically not resting on the wall of the duct 18. From this position, it can be moved transversely towards the inside the duct so as to flatten the latter.
• the device also includes air injection means which open into a region of the conduit 18 situated between the first and second crushing members 20 and 22 and, more precisely, in the vicinity of the first crushing member 20.
• the air injection means comprise a pipe 26 connected to a source of pressurized air (not shown), the end of this pipe being connected to the pipe 18 just downstream of the first crushing member 20.
• the injection of compressed air can be controlled by means of opening and closing the pipe 26. All types of controlled valves may be suitable for this purpose.
• the means for opening and closing the injection of compressed air comprise a crushing member 28 of conformation generally similar to the members 20 and 22, although of possibly smaller dimensioning, this member crushing 28 can be moved transversely to the pipe 26 between a relaxation position in which it allows the injection of compressed air into the duct 18 and a crushing position in which it prevents the injection of compressed air.
• the crushing members 20 and 22 comprise a movable piston or the like situated on one side of the duct 18 while, on the other side, this duct bears against a rigid wall element 30. When they occupy their crushing positions, the members 20 and 22 therefore come to crush the duct against the wall element 30.
• the discharge member 24 is located on the same side as the crushing members 20 and 22.
• the crushing member 28 which is used to control the injection of air through the pipe 26 works in the same way, this pipe being in abutment against a rigid wall element 32 on the side opposite to the member 28.
• the device according to the invention comprises means for timing the injection of compressed air, the movements of the crushing members 20 and 22 and the movement of the delivery member 24.
• these are hydraulic jacks supplied in turn with pressurized fluid by a rotary distributor.
• the crushing members 20 and 22, as well as the delivery member 24, are integral with the pistons of cylinders respectively designated by the references 21, 23 and 25.
• These cylinders are connected to fluid supply lines under pressure, respectively 21 A, 23 A and 25A, and to exhaust pipes, respectively 21B, 23B and 25B.
• the crushing member 28 may be integral with the piston of a jack 29 connected to supply lines 29A and exhaust 29B.
• the various fluid supply and exhaust pipes are connected to a distributor 36, for example a rotary distributor actuated by a motor 37, located on a fluid circuit 35 comprising a source of pressurized fluid.
• the distributor 36 is arranged so as to have the supply lines communicate in turn with the fluid source and the exhaust lines with the fluid exhaust to control the crushing members and the discharge member according to the timing cycle.
• timing means comprising a system of cams of suitable shapes cooperating with the output shaft of an engine, the convex parts of the cams urging the crushing and discharge members towards their respective crushing positions, while the concave parts would urge these organs towards their respective inactive positions.
• the concave and convex parts of the cams of appropriate lengths, would be angularly offset from one another.
• the crushing and delivery members are controlled by motors themselves managed by an electronic control so as to respect the desired timing.
• the clocking frequency of the cycles can be adjusted by means for varying the speed of the rotary distributor or that of the motor or motors used for clocking.
• Figure 1 allows to ensure that the conduit 18 has a single straight section, relatively short, directly located under the hopper, which reduces the price of the conduit and facilitates the handling and installation of this last when replaced.
• the conduit 18 is directed vertically and extends directly under the opening 12A of the hopper 12.
• the material contained in the hopper naturally tends to fall in the conduit under the effect of gravity.
• wet method with dilute flow it is possible to choose to horizontally arrange the section of conduit with which the crushing and discharge members cooperate. It can also be bent as shown in Figure 5.
• the device shown in Figure 1 comprises additional air injection means comprising an air line 38, permanently supplied under pressure and connected to the transport line 16 downstream of the second crushing member 22.
• the line 38 can be connected to the same source of pressurized air as line 26. It serves to accelerate the evacuation of the product and its continuous transport in line 16.
• the injection of air through line 38 can be continuous, which is unlikely to cause dust discharges into the hopper 12, the line portion 18 located upstream of line 38 being closed either by the member 20 , or by organ 22.
• FIGS. 2A to 2F the operating phases of the device are now described. These figures are extremely schematic and, for simplicity, only the hopper 12, the duct 18, the first and second crushing members 20 and 22, the discharge member 24 and the pipe d have been indicated on each of them. air injection 26, as well as the additional air injection means 38.
• Figure 2A shows the same situation as Figure 1, which corresponds to a filling phase in which the first crushing member 20 is in the relaxed position and allows the passage of the material in the conduit 18, while that the air injection means 26 are closed, that the delivery member 24 is in the inactive position and that the second crushing member 22 is in the crushing position.
• the entire portion of the conduit 18 located upstream of the second crushing member 22 is open, which allows this portion of the conduit to be supplied with material contained in the hopper 12.
• the timing cycle includes a discharge phase in which the first crushing member 20 is primarily in the crushing position, which prevents the descent of the material in the conduit 18 and the discharge of air into the hopper 12, and in which the second crushing member 22 is in the relaxed position, which allows the material downstream of the second crushing member to descend, initially contained in the portion of the conduit 18 located upstream of this second crushing member 22.
• the air injection means 26 pass from closing to opening, and the delivery member 24 changes from the inactive position to the active position.
• the member 20 is placed in the crushing position before placing the member 22 in the relaxation position. Then begins the delivery phase which can be broken down into two stages respectively illustrated by Figures 2C and 2D.
• the first and second crushing members 20 and 22 are respectively in the crushing position and in the relaxation position, and the means 26 for injecting air are open, while the repression 24 temporarily continues to occupy its inactive position.
• the injection of air through line 26 then initiates the delivery of the product and the latter is completed by the passage of the delivery member 24 to its active position shown in FIG. 2D.
• this breakdown of the delivery phase is only one example.
• the effects of air injection through the pipe 26 and the delivery by the member 24 complement each other to accelerate and regulate the delivery and the transport of the material downstream.
• the delivery phase there is at least one moment when the air injection means are controlled in the direction of their opening and a moment when the delivery member is controlled to pass from its inactive position to its active position.
• the timing cycle includes a decompression phase in which the first and second crushing members 20 and 22 are in the crushing position, the air injection means 26 are closed and the member discharge 24 is controlled from its active position to its inactive position.
• the compressed air injected at the end of the delivery phase is stored in the chamber 19 formed between the first and second crushing members 20 and 22.
• the delivery member 24 occupies its active position, the volume of this chamber is extremely small.
• the volume of this chamber is increased by passing the delivery member from its active position to its inactive position as shown in FIG. 2F. This results in an expansion of the air contained in this chamber which is in depression relative to atmospheric pressure. Consequently, when, at the end of the decompression phase, the first crushing member 20 is commanded towards its relaxed position in order to obtain again the situation in FIG. 2A and to restart the cycle, any risk of air backflow under pressure through the hopper 12 is eliminated, and the slight depression of the chamber 19 tends to suck the material contained in the hopper 12 more quickly into the conduit 18.
• the delivery member may have an active face 24A which extends over the major part of the section of the length of the section of the duct. 18 located between the two crushing members 20 and 22.
• the pressure of the air injected through line 26 or through line 28 can be between 1 and 12 bars.
• the device advantageously includes means for adjusting the relaxation position of the first crushing member 20, these means making it possible to limit the withdrawal of the member 20 relative to the conduit 18 in its relaxation position, so that, contrary to what the preceding figures show, said member 20 does not completely release this conduit in its relaxation position and possibly continues to cooperate with the conduit to give it a relaxation section less than its section in the free state.
• FIG. 3 shows an exemplary embodiment of these adjustment means.
• the crushing member 20 comprises an end portion 20A opposite the active portion of this member which cooperates with the conduit 18, and for example connected to the latter by a connecting rod 21 '.
• this end portion 20A slides with respect to a support 40 provided with an adjustable stop 42, constituted for example by a screw held in an opening in the support 40 .
• the end portion 20A cooperates in abutment with the stop 42 whose position therefore determines the position of extreme separation of the member 20 relative to the duct 18.
• the stop member 42 can be placed in a situation in which the member 20 slightly reduces the cross section of the duct 18 compared to that which this duct would have in the free state, in its relaxed position.
• the support 40 can constitute the body of the jack 21 mentioned above.
• Figure 4 schematically shows the configuration of the conduit 18 in the region of the discharge member 24 when the latter occupies its active position.
• This figure illustrates an advantageous variant in which the active face 24A of the member 24, that is to say the part of this member which cooperates directly with the conduit 18, has a width 1 which is less than the width L that presents the internal periphery of the conduit in the compressed state of the latter.
• These two widths are measured transversely to the conduit and, more precisely, perpendicular to the longitudinal axis of the conduit, in the plane of crushing of the latter. It can thus be seen that, even when the active position of the discharge member 24 corresponds to a situation in which the duct is practically crushed by this member, this crushing does not affect the "sides" of the drove.
• This arrangement makes it possible to limit the deterioration of the conduit in the region of the discharge member since, conventionally, it is the sides of the conduit which suffer the most during the crushing, until presenting practically definitive folds which harm the elastic recovery of the initial dimensions of the duct, and even ending up splitting.
• the duct 1 18 describes an arc between its connection to the hopper 112 and its connection to the transport line 116.
• the discharge member 124 and the rigid wall element 130 have a corresponding semi-circular shape, the member 124 moving radially relative to the arc of a circle as described by its active face 124A.
• This advantageous arrangement facilitates the transport of products which might form plugs in an elbow similar to the elbow 16A of Figure 1, the radius of curvature of the conduit 1 18 being much greater than that of this elbow.
• FIG. 5 shows another advantageous arrangement which consists in providing a decompression and mixing chamber 53 downstream of the second crushing member 122.
• An annular air inlet chamber 52 into which the pipe 138 opens is formed in the upstream part of chamber 53.
• the air-product mixture discharged downstream of the member 22 expands in the chamber 53 and mixes with the supply of air entering via the line 138, which improves the homogenization of the air-product mixture and promotes the projection of the material smoothly at the end of the lance 114.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Nozzles (AREA)
• Disintegrating Or Milling (AREA)
• Air Transport Of Granular Materials (AREA)
• Reciprocating Pumps (AREA)
• On-Site Construction Work That Accompanies The Preparation And Application Of Concrete (AREA)
• Filling Or Emptying Of Bunkers, Hoppers, And Tanks (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=9514047

Family Applications (1)

Country Status (9)

Families Citing this family (48)

Family Cites Families (11)

• 1997
  • 1997-12-02 FR FR9715148A patent/FR2771721B1/fr not_active Expired - Fee Related
• 1998
  • 1998-12-02 JP JP2000523137A patent/JP2001524437A/ja not_active Withdrawn
  • 1998-12-02 EP EP98958301A patent/EP1036024A1/fr not_active Withdrawn
  • 1998-12-02 US US09/555,728 patent/US6283680B1/en not_active Expired - Fee Related
  • 1998-12-02 CN CNB988117487A patent/CN1150121C/zh not_active Expired - Fee Related
  • 1998-12-02 KR KR1020007005986A patent/KR20010052111A/ko not_active Application Discontinuation
  • 1998-12-02 WO PCT/FR1998/002592 patent/WO1999028221A1/fr not_active Application Discontinuation
  • 1998-12-02 BR BR9815338-2A patent/BR9815338A/pt not_active Application Discontinuation
  • 1998-12-02 AU AU14392/99A patent/AU1439299A/en not_active Abandoned

Non-Patent Citations (1)

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