A pneumatic conveying system and a method for collecting objects and transporting them to a device and use of same

Abstract

The present invention relates to a method and a pneumatic conveying system for handling objects and transporting them to a device through a discharge convey line. The pneumatic system comprises a loading unit adapted to receive said objects through a receiving opening and a gas / air flow connection to an inlet convey line and an outlet convey line, the air / gas flow is allowed to pass through the inlet convey line, the loading unit(s) and the outlet convey line. The outlet convey line connects the air / gas flow by conveying lines to the discharge convey line. The system comprises an air / gas pump adapted to generate the air / gas flow through the inlet convey line into the loading unit, and the system may further comprises a control system. The invention also relates to a method for handling and transporting objects through a pneumatic conveying system from at least one loading unit through a discharge convey line to a device, an air / gas flow is flowing from an inlet convey line into the loading unit(s), and an air / gas pump is pumping air / gas through the inlet convey line, and a control system is controlling the pressure in the pneumatic conveying system.

Description

[0001] A pneumatic conveying system and a method for collecting objects and transporting them to a device and use of same

[0002] The present invention relates to a pneumatic conveying system for handling objects and transporting them to a device through a discharge convey line, the system comprises at least one loading unit adapted to receive the objects through a receiving opening and in gas / air flow connection to an inlet convey line and an outlet convey line, i.e. a gas / air flow is configured to pass through the inlet convey line, the loading unit(s) and the outlet convey line, said outlet convey line is fluidly connected or air / gas flow connected by conveying lines to the discharge convey line, and the system comprises an air / gas pump adapted to generate an air / gas flow through the inlet convey line into the loading unit, also, the system comprises a control system.

[0003] The invention also relates to a method for handling and transporting objects through a pneumatic conveying system from at least one loading unit through a discharge convey line to a device, an air / gas flow is flowing from an inlet convey line into the loading unit(s), and an air / gas pump is pumping air / gas through the inlet convey line, and a control system is controlling the pressure in the pneumatic conveying system.

[0004] Further the invention relates to the use of the pneumatic conveying system according to claims for performing the method.

[0005] The waste material / objects may be empty beverage bottles and cans of any size and material such as plastic, steel, aluminum, glass, plastic said waste material is recycling waste material. The waste material may also be disposable package.

[0006] Pneumatic conveying systems are used for transporting different kinds of material such as food, corn and granulates. Generally, air is blown through pipes via a pressure-blower and similar in order to move the material through the pipe. In this way the material in question can be moved from one point to another point.

[0007] US 6164491 B discloses a pneumatic product vending and delivery system. The system transports products such as bottles from a remote storage location to a vending terminal where a costumer may select a specific bottle through a control panel. A blower assists in transporting the bottles through the tube. The system is not adapted for transporting empty packaging such as bottles and cans from a delivery station to a compactor and a container. The system is not adapted to compress the objects as the purpose is to transport the objects without any damage taking place.

[0008] US 4180354 A discloses a pneumatic tube transmission system for transmitting a carrier in which an object is placed from one terminal to a remote terminal to allow delivery of the carrier into an open remote terminal. When the carrier is being transferred from the first terminal to the remote terminal, the carrier is positioned in the first terminal and the blower is activated to deliver positive pressure air through the first airline. A second airline draws a partial vacuum on the second end of the transmission line at the remote terminal. This forces the carrier to move through the line to the remote terminal where the object is removed from the carrier. The system is not suitable for transporting objects continuously or to compress the objects as they are to be delivered in the same state as they were from the beginning.

[0009] BE 710678 A discloses a pneumatic tube system where a suction in the tube sees to that objects such as bottles are transported through the tube. The system requires that each object is placed in the tube one by one. No compression of the objects takes place.

[0010] A container return system is generally arranged to collect waste containers for recycling. This may include used emptied beverage bottles and cans, or other waste material such as disposable packaging. The container return system must collect large amounts of waste material for recycling in a short period of time. In many installations, the container return system delivers the received objects to a backroom receiving facility and the required space here can be considerable. Further it can also require means for sorting and storing the received objects. The space requirement and the complexity cause cost to the system.

[0011] In a typical installation, the crushed or compressed objects are transferred to a box and stored in plastic bags. The plastic bag is replaced when full. This also requires available space to store the full plastic bag and is time consuming. Further the container return system is often stopped when the box is full, and an empty one is placed.

[0012] In order to handle recycling packages such as bottles and cans it is common to transport the objects on a transport band. This transport band runs from a delivery station where the customer puts the bottle / can and to a box where the bottles or cans are selected.

[0013] These systems are quite time-consuming for the customer as the system is fed one by one, that is the customer must wait for a bottle or a can to disappear before a new one is fed to the system. Further, the collecting boxes are filled in a short time and must be replaced by a new one. This is also timerequiring and requires staff just for emptying the boxes. Further the rest-liquid and rest food from the waste material make the inside of the system dirty so it is necessary to clean it now and then.

[0014] With other words it is desirable to be able to develop an improved convey system for collecting and transporting objects such as bottles and cans in can bottle and can deposit recycling systems and / or disposable packaging in such a way, that the objects can be handled without any delay and does not significantly contaminate the system with food residues and liquid residues. The objects are transported away from the delivery station so fast that the user just can empty large portions of the objects into the delivery station without any risk of overloading the system. As the waste material is compressed after it has passed through the convey system very little or no contamination of the inner side of the tubes and the equipment as such takes place. In this way there is quite little or no need for cleaning the system or implementing special cleaning procedures.

[0015] The present invention seeks generally to improve conveying system for collecting and transporting objects such that the abovementioned insufficiencies and drawbacks of today's conveying systems are overcome or at least it provides a useful alternative.

[0016] Up to this day, prior art has failed to teach a simple and yet reliable and inexpensive conveying system which in a safe and reliable manner, without substantially increasing the cost of the system, is able to satisfy the abovementioned much desired characteristics of the mentioned conveying system.

[0017] According to the invention, a pneumatic conveying system is provided, as per the introductory part of this specification, and wherein the device is a compactor for compressing and / or puncturing and / or crushing the objects, the compactor arranged between an outlet of the discharge convey line and a collecting unit, and is adapted to compress and / or puncture and / or crush the objects before they reach the collecting unit,

[0018] - means for providing a negative air / gas pressure in the outlet convey line

[0019] - and the control system is configured to control process parameters in the system including the pressure.

[0020] The pressure devices may comprise any type of air-source such as a blower, air pump, fan, or other device capable of creating a pressure differential and for forcing air or other gas, under pressure, through the convey line. As such, the pressure devices are configured to generate a positive air- pressure for purposes of introducing air into the first convey line and an air flow with a certain laminar flow velocity in the loading unit and for causing an under-pressure in the outlet convey line. This causes the objects introduced into the convey lines to travel through the convey lines. The means for providing a negative pressure generate a negative air pressure within the outlet convey line below an ambient atmospheric pressure. The air / gas pump is required to generate a pressure in the inlet convey line.

[0021] As the waste material - such as plastic bottles or cans or disposable packaging - drop down in the loading unit and reaches the bottom part of this, - the laminar flow in the loading unit is caused by the pressure difference between the inlet convey line and the outlet convey line - it is sucked into the outlet convey line and passes through an injector and further to the discharge convey line. From here it is led to the compactor / compressor where it is compressed / crushed / punctured before it drops down into the collecting unit, which is typically a big container placed outside the building where the container is placed.

[0022] In this way the convey system can operate nearly through the whole day without any interruptions, as such a container can hold more than 150 times what a bag used in the known systems is capable of. Further the system does not require staff inside the building to be responsible for watching the system being full and stopping it each time a box / bag is full. The full container - placed outside the building where the system is situated - is driven directly away without bothering any inside staff. An additional benefit is that the plastic bags used in the existing systems are not necessary.

[0023] The system combines pneumatic vacuum transport and pneumatic overpressure transport, and the control system controls the two pressures in such a way that we have nearly even pressure (0,9-1 bar) in the loading unit, and a laminar flow through the loading unit of around 10-40 m / second. The objects are in this way pushed into the inlet convey line, where the under-pressure sucks the material to the discharge convey line from where it is dropped down into the compactor where it is compressed / crushed / punctures. From here it is led to the container. The injector let the material pass through, while the injector also causes an under-pressure in the outlet convey line, as the pressurized air from the pressure blower passes through the injector.

[0024] There may be more than one loading unit. If two loading units are used, they are connected to each other by a pipe / tube and the inlet convey line is connected to the first loading unit while the outlet convey line is connected to the second loading unit.

[0025] As the objects are not compressed / crushed / punctured before they are led into the tubes of the conveying system there is no need for cleaning the tubes inside. If the objects are compressed before they are dropped down into the loading unit there will be a leek from the objects such as food residues or liquid from beer or soda. These residues are sugary, sticky and greasy and will adhere to the inside of the tubes. So, after a while typically every second hour a day the system must be stopped in order to clean the inside. Due to the fact that the compactor is placed just before the objects are led to the container there is no need for this further cleaning process, and there is no need for stopping the transport system.

[0026] Further, as the compactor is placed at the end of the line the need for an inside-room for a compactor before the loading unit is avoided. This is very beneficial as space in a store where this system typically is used is in short supply and expensive. The compactor is now placed outside the store and the noise from the compactor is also avoided in the store area.

[0027] Furthermore, since the objects are not compressed before they are carried by the air stream to the compactor, less energy is used than if they were compressed before they ended up in the unit.

[0028] This is due to the larger surface that the objects have compared to the same object in a compressed state

[0029] According to an embodiment, the compactor is a dual roller comprising a first roller and a second roller having parallel axes rotatably mounted in a housing, and a drive mechanism for rotating the rollers synchronously opposite one another, said objects are compressed and / or punctured and / or crushed in a gap between the rollers before leaving the compactor.

[0030] The compactor is especially suitable for being used in reverse vending machines and where a number of items such as bottles and cans are to be compressed, crushed or punctured in a short period of time.

[0031] The two rollers rotate in opposite directions of rotation such that the items to be crushed, punctured or compressed is handled between the rotating rollers. The items are supplied from an inlet opening in the housing and discharged downwards from here.

[0032] According to an embodiment the outer surfaces of each roller comprise an assembly of longitudinal rails extending from a cylindrical surface of the rollers, and space between the rails arranged so the rails of one roller extend radially into the space between adjacent rails on the opposite roller in an alternating manner thereby forming a gap between the rollers, the longitudinal rails arranged parallel with the axes of the rollers and extend substantially throughout the length of the rollers and are attached to the circumferential cylindrical surface of the rollers by fastening means.

[0033] The crushing rails mounted on the surface of the rollers act as crushing teeth and compress the items caught between the rollers in the gap. The rails are so arranged that the rail of one roller does not collide with the rail of the other roller during rotation of the rollers. The gap between the two rollers is arranged to allow the items to pass through in a compressed / crushed or in an intended punctured state.

[0034] According to one embodiment are side walls of the rails substantially straight and flat or slightly curved and the side walls converge towards each other at an angle V, further a longitudinal central axis of a rail is parallel to the longitudinal central axis of the longitudinal central axis to the opposite situated space into which it extends radially, and the two longitudinal central axes lie opposite each other. Du to the very specific relationship between a rail and the opposite placed space the objects will be pressed and leave the compressor one by one. I.e., in contrast to the known compressors which cause the objects to stick together, the objects are separated after compression and can therefore be sorted afterwards into material types.

[0035] The angle V of the rails is typically 20-459.

[0036] According to one embodiment comprises the drive mechanism a motor fitted with a speedregulating gear in order to control the speed, said drive mechanism is controlled by the control system.

[0037] The rollers require large and adjustable supplied energy in order to rotate and crush the items. Therefor a drive mechanism where the motor drives the rollers by a chain- or belt drive is the most convenient way to deliver the energy and to regulate the supplied energy.

[0038] According to one embodiment, the axis of one of the rollers is adjustable by parallel displacement of said axis, whereby its distance to the other roller is changed, and whereby the gap between the rollers is adapted to be changed in size.

[0039] According to one embodiment is the size of the gap -that is the smallest distance between the rollers - a function of the size and type of material of the objects passing through the compactor.

[0040] The axis of one of the rollers is adjustable by parallel displacement of the axis whereby its distance to the other roller is changed, and whereby the gap between the rollers is adapted to be changed in size.

[0041] The gap can be adjusted whereby items of different sizes and material can be handled. This makes the dual roller compactor extremely flexible. The gap is measured as the distance between the upper surface of that rail being closest to the opposing roller and the bottom of the spacer it extends into. The compression or the size of the items is determined by the gap which is determined by the rails and the distance between the axes of the rollers. If the size of compression or the fragments of items should be changed it is possible to do so by displacing one of the rollers, so the gap is reduced or enlarged. By activity is to understand that the rollers may be active that is they are handling the objects by crushing / puncturing / compressing or the rollers stand still. The activity of the compactor may be controlled by the control system.

[0042] According to one embodiment is one of the rollers mounted in a spring-actuated slide guide adapted to move the roller in relation to the other roller, and by moving the former roller the gap between the rollers is changed in size.

[0043] The first roller of the dual roller can move slightly away from the second roller as its bearings are mounted in a spring-actuated slide guide.

[0044] This construction ensures that the machine is not damaged or that the damage is limited if, for example, a deposit box or bottle filled with e.g., frozen liquid or another unintentional massive object etc. The control system controls the stop and start of the rollers.

[0045] According to one embodiment comprises the means a pressure blower for providing pressurized gas / air, said pressure blower air / gas flow connecting with an injector and arranged to form a negative air / gas pressure in the outlet convey line, said injector placed between the discharge convey line and the outlet convey line.

[0046] According to one embodiment is the injector gas / air flow connected by a second convey line to the outlet convey line, the injector is further gas / air flow connected to the discharge line, said injector allowing the objects to pass through the injector and leave the injector through the discharge convey line.

[0047] According to one embodiment is the control system configured to control the air / gas pressure from the pressure means, and the pressure from the air pump, by said pressure the objects pass from a bottom part of the loading unit(s) through the outlet convey line and further through the discharge convey line through the outlet and into the compactor and from here is led into the collecting unit.

[0048] The pressurized air is passed through the injector and to the discharge convey line, to which it is directly connected. As the injector also have a connection to the outlet convey line of the collecting unit through the second convey line, the flow from the blower through the injector makes an underpressure in the second convey line and thereby in the outlet convey line of the loading unit. The objects are also passing through the injector.

[0049] According to one embodiment, the control system is adapted to control the pressure in the system in such a way, that a laminar airflow in the loading unit is around 10-40 m / s preferably 20-30 m / s.

[0050] According to one embodiment, the pressure in the outlet convey line is below a value an ambient atmospheric pressure, and the pressure in the inlet convey line is essentially above same value of an ambient atmospheric pressure.

[0051] The control system sees to that the air flow velocity in the loading unit is suitable, that is around 10- 40 m / s, preferably 20-30 m / s and more preferably 25-30 m / s. This is done by regulating the pressure in the inlet convey line and the outlet convey line. When the objects leave the loading unit the under-pressure in the outlet convey line sees to, that the objects are sucked up to the injector and then pushed by the airflow from the pressure blower passing through the injector.

[0052] According to one embodiment, the collecting unit has a space-volume of at least 2 m3, preferably more than 2 m3, more preferably more than 10 m3, placed in relation to the compactor in such a way, that the compressed and / or punctured objects is falling down in said collecting unit.

[0053] The collecting unit is preferably a container. Using big containers - normally placed outside the building where the system is placed - removes the need to collect the material in bags. The material simply drops down in the container as it is, that is compressed / crushed / punctured. The need to stack bags with the material for recycling is hereby removed.

[0054] The containers the containers can be as large as 6, 5*2, 5*3 m3 that is 48,75 m3. The container may also be a big plastic bag attached to the outlet.

[0055] According to one embodiment are the objects deposit objects such as bottles and cans in can bottle and can deposit recycling systems and / or disposable packaging.

[0056] The invention also relates to a method as described in the introductory part of the description and where a suction is provided by means in an outlet convey line connected to the loading unit, and that the device is a compactor placed after an outlet of the discharge convey line presses and / or punctures and / or crushes the objects before they reach a collecting unit, and the control system controls process parameters of the system including the pressure.

[0057] According to one embodiment, the control system controls the activity of the compactor, said compactor being a dual roller comprising two rollers with a gap between the rollers in said gap the objects are pressed and / or punctured and / or crushed before leaving the compactor.

[0058] According to one embodiment, the control system is configured to control the pressure in the convey lines so the pressure in the inlet convey line is above an ambient atmospheric pressure, and the pressure in the outlet convey line is below an ambient atmospheric pressure providing a laminar air / gas flow velocity in the loading unit, whereby the objects are moved through the conveying lines into the compactor.

[0059] According to one embodiment, the suction is provided by a pressure blower to which the outlet convey line is air / gas flow connected, and the pressure blower blows air / gas through an injector causing the suction in the outlet convey line, said injector is placed between the discharge line and the outlet convey line, a second convey line arranged between the injector and the outlet convey line provides the suction in the outlet convey line as the pressurized air from the pressure blower flows through the injector.

[0060] According to one embodiment, a negative pressure or an equal pressure is provided in the upper part of the loading unit.

[0061] By having a slight negative pressure in the upper part of the loading unit odor may be sucked out with the material flow.

[0062] According to one embodiment, a laminar airflow is obtained around 10-40 m / s preferably 20-30 m / s, and the pressure in the outlet convey line is below an ambient atmospheric pressure, and the pressure in the inlet convey line is essentially above an ambient atmospheric pressure.

[0063] According to one embodiment, the objects are fed into the loading unit in a continuous stream and leaves the compactor one by one in a continuous stream compressed and / or punctured and / or crushed and are led into the collecting unit.

[0064] According to one embodiment the receiving-opening of the loading unit points in the opposite direction of gravity.

[0065] According to one embodiment all the convey lines including the inlet convey line, the outlet convey line and discharge convey line are pneumatic transfer tubes. By "pneumatic transfer tubes" is to understand, that the tubes are transporting under-pressure or over-pressure gas / air and are able to withstand the different pressures.

[0066] According to one embodiment, the objects are fed into the loading unit in a continuous stream.

[0067] According to one embodiment, the loading unit is an integrated part of the inlet and outlet convey line connecting them with each other through the loading unit and an opening is provided in the top of the loading unit allowing objects to fall down into the loading unit and from here pass into the outlet convey line.

[0068] According to one embodiment, the control system is adapted to control all process parameters such as filling of the loading unit, filling of the collecting unit, pressure in the convey lines. Definitions

[0069] Deposit recycling - means recycling of materials where consumers pay a deposit.

[0070] In general - when this expression is used when mentioning a feature relating to the present invention, it must be understood that the feature may be used with all embodiments of the invention, even if the mentioning is made in the detailed part of the document.

[0071] Brief description of the drawings

[0072] FIG. 1 is a perspective view of a pneumatic conveying system according to the invention.

[0073] FIG. 2A is a perspective view of a compactor where a drive mechanism is removed, FIG. 2B and 2C are views of rail parts and a surface section which may replace the rails shown in fig. 2A.

[0074] FIG. 3 is a front view of the compactor shown in fig 2A.

[0075] FIG. 4 is a perspective view of the device shown in fig 2 and 3 and where the drive mechanism is shown.

[0076] FIG. 5 is a perspective view of a loading unit used in the pneumatic conveying system shown in fig 1.

[0077] FIG. 6 is a sectional view through an injector used in the pneumatic conveying system shown in fig 1.

[0078] FIG. 7 is an embodiment of a funnel guide according to the invention.

[0079] FIG. 8 is an embodiment of a scraper according to the invention.

[0080] The invention will be explained with reference to fig. 1. Fig. 1 shows a system 1 according to the invention, where an object 2 such as a plastic bottle is thrown down in a loading unit 4 for being transported through conveying lines / tubes. The object 2 is typically delivered from a delivery-station placed in a store, where the customer delivers his bottles / cans back to the store in order to have the waste objects 2 recycled. An object 2 is also seen in fig. 1 leaving the system through an outlet 14 of a discharge convey line 7. The objects 2 - delivered to the system 1- are delivered in a continuous flow. The customer may simply empty a whole sack of objects 2 into the delivery-station as the system 1 is able to receive and handle the objects 2 without any delay as the objects 2 leave the loading unit 4 fast one by one.

[0081] The system 1 comprises the loading unit 4 that receives the objects 2. The loading unit 4 is explained in detail with reference to fig 5. The loading unit 4 is physically connected to an inlet convey line 5 - a tube - and an outlet convey line / tube 6. Air / gas flows through the inlet convey line 5, the loading unit 4 and the outlet convey line 6. The outlet convey line 6 is flow connected with an injector 11 through a second convey line 12, which is also air / gas flow connected to the discharge convey line 7. A pressure blower 8 provides pressurized gas / air and is through a first convey line 18 air gas connected with the injector 11 and thereby the discharge convey line 7.

[0082] The pressure blower 8 forms a negative air / gas pressure in the outlet convey line 6 due to the established gas / air flow lines through the injector 11. An air / gas pump 9 generates an air / gas flow through the inlet convey line 5 into the loading unit 4. A laminar airflow is then obtained in the loading unit 4: around 10-40 m / s, due to the pressure in the outlet convey line 6 is below ambient atmospheric pressure (suction), and the pressure in the inlet convey line 5 is above ambient atmospheric pressure. Thereby, the objects 2 pass from a bottom part of the loading unit 4 through the outlet convey line 6 and further through the injector 11 and the discharge convey line 7, through the outlet 14 of the discharge convey line 7 into a compactor 30 and from here the objects 2 are led to the collecting unit 3. The pressure may be controlled by a control system 10.

[0083] The discharge convey line 7 comprises a first portion 15 with a diameter dl of the tube of around 200 mm placed directly in connecting with the injector 11. A second portion 16 with a diameter d2 of the tube of around 400 mm is placed in a distance to the injector 11. The two pieces are connected to each other with a connection tube which may be a conic transition-tube. By increasing the diameter of the tube close to the outlet 14, the flow velocity of the air / gas is reduced, and the objects may simply fall down into the compactor 30 placed under the outlet 14.

[0084] The objects passing from the outlet 14 into the compactor 30 are compressed and / or punctured and may either assume a compacted design or may have been granulated in a granulator 31.

[0085] In general, the compactor 30 may be a dual roller or double roller comprising two rollers 32, 33 as shown in the embodiment of figs. 2, 3 and 4.

[0086] The compactor 30 will be explained with reference to fig. 2-3 showing a perspective view and a front view of the compactor. The compactor 30 is constructed for compressing and / or tearing apart and / or crushing plastic or metal items such as empty bottles and cans, or disposable packaging typically produced in cardboard or paper or plastic. The compactor 30 comprises a first roller 32 and a second roller 33 having parallel axis 34a, 34b. The two rollers 32, 33 are rotatable mounted inside a housing 35 and have an outer cylindrical circumferential surface 36.

[0087] The compactor 30 comprises a drive mechanism 43 (see fig 4) for rotating the rollers 32,33 synchronously opposite directions relative to one another. The drive mechanism 43 comprises a motor 42 fitted with a speed-regulating gear 44 in order to control the speed. The motor 42 is adapted to drive the rollers by a chain- or belt drive 45.

[0088] In general, the outer surfaces 36 of each roller 32, 33 comprise an assembly of protruding parts 37 either in form of alternating rails 37 extending continuously from the cylindrical surface 36 along the length or width of each roller 32, 33, or in form of in form of alternating rail parts 37 - or teeth - extending non-continuously from the cylindrical surface 36 as shown in fig. 2B

[0089] Normally, the alternating rails or series of teeth 37 extend from the cylindrical surface 36 along a right line parallel to the rotation axis 34a, 34b are positioned with an equal distance corresponding to a space 38. Each space 38 between the rails or teeth 37 is arranged so the rails or teeth 37 of one roller 32 extend radially into the space 38 between adjacent rails or teeth on the opposite roller 33 in an alternating manner. Thereby a gap is formed between the rollers 32,33, and this gap is where the objects 2, such as a plastic bottles, cans or the like are received and compressed or worn. The objects 2 are delivered to the compactor 30 through an inlet opening 39 which is normally positioned above the gap. Normally, the longitudinal rails or line of teeth 37 are arranged parallel with the axes 34a, 34b of the rollers 32,33, and normally, the length of the rails or the line of teeth 37 is the same as the length or width of the rollers 32,33. Normally, the rails 37 are evenly distributed over the surface 36 of the rollers 32,33 and removably fastened to the surface 36 of the rollers 32,33 by fastening means comprising devices such as a bolt 40, alternatively the rails 37 may be fastened by welding. If the protruding parts 37 are constituted by rail parts or teeth, the teeth 37 may be positioned in straight lines or the teeth 37 may be positioned along lines which are inclining relative to the axes 34a, 34b, or the teeth 37 may be positioned according to another pattern. The teeth 37 are formed as part of or attached to a surface sections comprising a plurality of teeth which surface sections are fastened to the roller 32, 33.

[0090] Fig. 2B shows a cut-through view of a surface section comprising teeth, and fig. 2C shows a top view of a surface section comprising teeth 37.

[0091] The protruding parts 37 - whether they comprises rails or parts of rails - normally comprise a straight front surface 37f facing in the rotation direction and / or a straight back surface 37b facing away from the rotation direction. The straight front surface 37f may either extend radially from the surface section i.e. perpendicularly or in an angle of 90 degrees to the surface section, or the straight front surface 37f may extend in an angle above 90 degrees relative to the surface section e.g. at an angle above 95 deg., and / or at or below 135 deg. The straight back surface 37b may either extend radially from the surface section i.e. perpendicularly or in an angle of 90 degrees to the surface section, or the straight back surface 37b may extend in an angle above 90 degrees relative to the surface section e.g. at an angle above 95 deg., and / or at or below 135 deg.

[0092] Normally, the rails or rail parts 37 comprises a flat or slightly curved upper surface, however, according to one embodiment, the straight front surface 37f facing in the rotation direction and the straight back surface 37b facing away from the rotation direction are both inclined and meets in a point in such a way that the front and the back surfaces 37f and 37b form an inverted V.

[0093] The surface sections comprising the rail parts 37 may be fastened to the rollers 32, 33 by bolts or they may be welded to the rollers 32, 33.

[0094] The axis 34a, 34b of each of the rollers 32,33 is adjustable. It is possible to provide a parallel displacement of the axes 34a, 34b by an adjustment device. By activating this the distance between the rollers 32,33 is changed. Thereby the gap between the rollers 32,33 is changed in size. One of the rollers is suspended in a slide bearing and is displaced by a spring action 46. This is relevant if a larger and harder object than intended tries to pass. If the roller were not able to move there would be a risk that the rollers 32,33 are damaged.

[0095] The rails 37 are replaceable longitudinal rails 37 and removable attached to the circumferential surface 36 of the rollers 32,33. When using the compactor 30 with two rollers 32, 33, objects 2 such as plastic bottles are delivered through the inlet opening 39 -see fig 2 and 3 - and is compressed by the opposite turning rollers 32,33. The compressed or torn apart items fall down and is collected in the container 3 for being transported away. The rails 37 work as crushing teeth. The difference between this construction and the commonly known constructions is that the teeth are not a small tooth-shaped device, but a force-resistant component formed as a rail and running in the whole length of the roller it is attached to. This makes it less sensible to large forces as the compressing force is distributed along the whole length of the rail 37 and transported to the fastening means placed along the whole length of the rail. The dual roller compactor 30 is especially useful for reverse vending machines as it is very effective and wear resistant. It is also very useful in relation to handling and compressing trash of any kind including can and bottle deposit as it is able to handle a big number of items in a short time and compress, crush, puncture or tear them apart. The fastening means 40 used to attach the rails 37 to the surface 36 may be placed in holes and cavities in the rollers and may at the top comprise or be equipped with devices suitable for tearing the items apart. These devices may be interchangeable.

[0096] When used for crushing the items they are reduced to particle size or granule that can be recycled.

[0097] The dual roller 30 makes it possible to compress objects of different sizes or made of different material such as steel, copper, aluminum and without the dual roller to get stuck.

[0098] Typically, the items 2 are crushed by running them between the two pressing and cutting rollers 32,33 that mesh with each other which press the two opposite walls of the item such as a bottle against each other. Further cuts of the wall of the items are provided when cutting teeth is arranged on the rails.

[0099] The cutting also facilitates letting air escape from an item such as a bottle which typically is closed by a closing cap during crushing. The residual fluid in the bottle is then leaving the crushed bottle and as it takes place after the transport of the objects through the pneumatic tubes the tubes of the system are not in any way greased with the sticky substance. The residual fluid is just left in the collecting unit 3 together with the crushed objects 31.

[0100] The construction of the loading unit 4 and its relation to the inlet and outlet conveying lines 5,6 will be explained with reference to fig 5. It comprises a hopper 20 physically connected to a horizontal tube 19 comprising the bottom part. The horizontal tube 19 comprises the two convey lines 5,6 connecting them directly with each other. The hopper 20 is placed above the tube 19 and is connected directly to the tube 19 and with an opening in the bottom allowing the objects 2 to drop down into the tube 19 to the bottom part through an opening in the tube 19. The whole construction is supported by a frame 21. The tube 19 constitutes the bottom of the loading unit / hopper 4, 20.

[0101] Fig 6 is a sectional view through the injector 11. The arrows show the airflow through the injector 11 and it also shows an object 2 passing through the injector 11 caused by the suction provided by the airflow - from the pressure-blower 8 - through the injector 11. When the object 2 has passed the injector 11 it is pressed out of the convey line due to the pressurized air / gas from the pressure blower 8.

[0102] Figs. 7A, 7B and 7C show three different views of one embodiment of a funnel guide 51 which may be added to a standard pneumatic conveyor system according to the invention. From the inlet opening 39 to the gap between the rollers 32, 33 there is a short passage or funnel. To guide the incoming objects 2 into the gap, the lower part of the passage may comprise a funnel guide 51. The shown embodiment of the funnel guide 51 has an upper end 52 attached inside the funnel close to the inlet opening 39, and a lower end 53 attached just above the gap between the rollers 32, 33. In general, the funnel guide 51 is attached to or formed as part of an inner surface of the funnel above the gap and guides incoming objects 2 to a position where the objects 2 are caught between the rollers 32, 33. In general, the funnel guide 51 may be adapted to specific objects 2 and the mounting of a funnel guide 51 inside the funnel may be used to optimize catching of a specific object defined by its size and weight such as aluminium cans, or plastic bottles, or another objects etc. The mounting of the funnel guide 51 is illustrated in fig. 3.

[0103] Figs. 8A and 8B show a scraper 54 which may be applied to a pneumatic conveyor system of the invention if the protruding parts 37 of the rollers 32, 33 are rail parts or teeth positioned with a distance between neighboring rail parts or teeth 37. The scraper 54 shown in fig. 8 comprises a body and from one side of the body a series of teeth 55 extend, the body is further provided with openings 56 for bolts which may be used to fasten the scraper 54 to the compactor 30. Alternatively, the scraper 54 may be welded to the compactor 30. It is illustrated in fig. 3 where the scraper 54 may be positioned in connection with the first roller 32, a second scraper may also be positioned in connection with the second roller 33. Also, more than one scraper 54 may be positioned in connection with the same roller 32, 33.

[0104] In general, one or more scrapers 54 comprising a body and a plurality of protruding teeth may be positioned in connection with one or both rollers 32, 33. Each scraper 54 is fixed to an inner surface of the compactor 30, in such a way that the body of the scraper 54 cannot move while the teeth comprises at least one surface being in close proximity to the surface 36 of the roller 32, 33 while the roller rotates. "Close proximity" is normally less than 10 mm, or less than 5 mm or less than 2 mm.

[0105] Rail parts or teeth 37 are good at grabbing objects 2 and forcing the objects 2 in between the rollers 32, 33, however, to prevent the grabbed objects from continuing to be attached to the surface of the roller 32, 33, a scraper 54 may be attached in connection with the outlet side of the roller gab, i.e. below the rollers 32,33.

[0106]

Claims

Claims1. A pneumatic conveying system (1) for handling objects (2) and transporting them to a device through a discharge convey line (7), the system (1) comprising- at least one loading unit (4) adapted to receive said objects (2) through a receiving opening and in air / gas flow connection to an inlet convey line (5) and an outlet convey line (6), such that an air / gas flow is allowed to pass through the inlet convey line (5), the loading unit(s) (4) and the outlet convey line (6),- said outlet convey line (6) is fluidly connected or air / gas flow connected by conveying lines to the discharge convey line (7),- said system (1) comprising an air / gas pump (9) adapted to generate an air / gas flow through the inlet convey line (5) into the loading unit (4),- and the system (1) further comprises a control system (10), characterized in that- the device is a compactor (30) for compressing and / or puncturing and / or crushing the objects, the compactor (30) arranged between an outlet (14) of the discharge convey line (7) and a collecting unit (3), and is adapted to compress and / or puncture and / or crush the objects (2) before they reach the collecting unit (3),- means for providing a negative air / gas pressure in the outlet convey line (6),- and the control system (10) is configured to control process parameters in the system including the pressure.

2. A pneumatic conveying system (1) according to claim 1 characterized in that the compactor (30) is a dual roller or double roller comprising a first roller (32) and a second roller (33) having parallel axes (34a, 34b) rotatably mounted inside a housing (35), and a drive mechanism (43) for rotating the rollers (32,33) synchronously opposite one another, said objects (2) are compressed and / or punctured and / or crushed in a gap between the rollers (32,33) before leaving the compactor (30).

3. A pneumatic conveying system (1) according to claim 2 characterized in that each roller (32,33) comprise an assembly of longitudinal rails or rail parts (37) extending from a cylindrical surface (36) of the rollers (32,33), and a space (38) between the rails or rail parts (37) arranged so the rails or rail parts (37) of one roller extend radially into the space (38) between adjacent rails or rail parts (37) on the opposite roller in an alternating manner thereby forming a gap between the rollers (32,33), the longitudinal extending rails or rail parts (37) may be arranged parallel with the axes (34a, b) of the rollers (32,33), and normally extend substantially throughout the length of the rollers (32,33) and are attached to the circumferential cylindrical surface (36) of the rollers (32,33) by fastening means.

4. A pneumatic conveying system (1) according to claim 3 characterized in that side walls comprising a front surface (37f) and a back surface (37b) of the rails or rail parts (37) are substantially straight and flat or slightly curved, and the front surface (37f) and / or the back surface (37b) may extend radially from the surface of the roller (32, 33), or the front surface (37f) and / or the back surface (37b) may extend at an angle larger than 90 deg and smaller than 120 deg. from the surface of the roller (32, 33).

5. A pneumatic conveying system (1) according to claim 3 characterized in that a longitudinal central axis of a rail (37) is parallel to the longitudinal central axis of the longitudinal central axis to the opposite situated space (38) into which it extends radially, and the two longitudinal central axes lie opposite each other.

6. A pneumatic conveying system (1) according to claim 2, 3 or 4 characterized in that the drive mechanism (43) comprises a motor (42) fitted with a speed-regulating gear (44) in order to control the speed, said drive mechanism (43) is controlled by the control system (10).

7. A pneumatic conveying system (1) according to claim 2,3, 4 or 5 characterized in that the axis (34a, b) of one of the rollers (32,33) is adjustable by parallel displacement of said axis (34a, b), whereby its distance to the other roller (32,33) is changed, and whereby the gap between the rollers (32,33) is adapted to be changed in size.

8. A pneumatic conveying system (1) according to claim 2,3,4, 5 or 6 characterized in that the size of the gap being the smallest distance between the rollers (32,33) is a function of the size and type of material of the objects (2) passing through the compactor (30).

9. A pneumatic conveying system (1) according to any of the claims 2-7 characterized in that one of the rollers (32,33) is mounted in a spring-actuated slide guide (46) adapted to move the roller in relation to the other roller, and by moving the former roller (32,33) the gap between the rollers (32,33) is changed in size.

10. A pneumatic conveying system (1) according to any of the previous claims characterized in that the means comprises a pressure blower (8) for providing pressurized gas / air, said pressure blower (8) air / gas flow connecting with an injector (11) and arranged to form a negative air / gas pressure in the outlet convey line (6), said injector (11) placed between the discharge convey line (7) and the outlet convey line (6).

11. A pneumatic conveying system (1) according to claim 9 characterized in that the injector (11) is gas / air flow connected by a second convey line (12) to the outlet convey line (6), the injector(11) is further gas / air flow connected to the discharge line (7), said injector (11) allowing the objects (2) to pass through the injector (11) and leave the injector (11) through the discharge convey line (7).

12. A pneumatic conveying system (1) according to any of the previous claims characterized in that the control system (10) is configured to control the air / gas pressure from the pressure means (8), and the pressure from the air pump (9), by said pressure the objects pass from a bottom part of the loading unit(s) (4) through the outlet convey line (6) and further through the discharge convey line (7) through the outlet (14) and into the compactor (30) and from here is led into the collecting unit (3).

13. A pneumatic conveying system (1) according to any of the previous claims characterized in the control system (10) is adapted to control the pressure in the system (1) in such a way, that a laminar airflow in the loading unit (4) is around 10-40 m / s preferably 20-30 m / s,14. A pneumatic conveying system (1) according to any of the previous claims characterized in the pressure in the outlet convey line (6) is below a value of an ambient atmospheric pressure, and the pressure in the inlet convey line (5) is essentially above same value of ambient atmospheric pressure.

15. A pneumatic conveying system (1) according to any of the previous claims characterized in that the collecting unit (3) has a space-volume of at least 2 m3, preferably more than 2 m3, more preferably more than 10 m3, placed in relation to the compactor in such a way that the compressed and / or punctured objects (2) is falling down in said collecting unit (3).

16. A pneumatic conveying system (1) according to any of the previous claims characterized in that the objects (2) are deposit objects such as bottles and cans in can bottle and can deposit recycling systems and / or disposable packaging.

17. Method for handling and transporting objects (2) through a pneumatic conveying system (1) from at least one loading unit (4) through a discharge convey line (7) to a device, an air / gas flow is flowing from an inlet convey line (5) into the loading unit(s) (4), and an air / gas pump (9) is pumping air / gas through the inlet convey line (5), and a control system (10) is controlling the pressure in the pneumatic conveying system (1) characterized in a suction is provided by means in an outlet convey line (6) connected to the loading unit (4), and that the device is a compactor (30) - placed after an outlet (14) of the discharge convey line (7) - presses and / or punctures and / or crushes the objects (2) before they reach a collecting unit (3),and the control system (10) controls process parameters of the system including the pressure.

18. Method according to claim 16 characterized in the control system (10) controls the activity of the compactor (30), said compactor (30) being a dual roller comprising two rollers (32,33) with a gap between the rollers, and in said gap the objects (2) are pressed and / or punctured and / or crushed before leaving the compactor (30).

19. Method according to claim 16 or 17 characterized in the control system (10) is controlling the pressure in the conveying lines so the pressure in the inlet convey line (5) is above an ambient atmospheric pressure, and the pressure in the outlet convey line (6) is below an ambient atmospheric pressure providing a laminar air / gas flow velocity in the loading unit (4), whereby the objects (2) are moved through the conveying lines into the compactor (30).

20. Method according to claim 16,17 or 18 characterized in that the suction is provided by a pressure blower (8) to which the outlet convey line (6) is air / gas flow connected, and the pressure blower (8) blows air / gas through an injector (11) causing the suction in the outlet convey line (6), said injector (11) is placed between the discharge line (7) and the outlet convey line (6), a second convey line (12) arranged between the injector (11) and the outlet convey line (6) provides the suction in the outlet convey line (6) as the pressurized air from the pressure blower (8) flows through the injector (11).

21. Method according to claim 16,17,18 or 19 characterized in that a negative pressure or an equal pressure is provided in the upper part of the loading unit (4).

22. Method according to claim 16, 17,18,19 or 20 characterized in that a laminar airflow is obtained around 10-40 m / s preferably 20-30 m / s, and the pressure in the outlet convey line (6) is below ambient atmospheric pressure, and the pressure in the inlet convey line (5) is essentially above ambient atmospheric pressure.

23. Method according to any of the claims 16-21 characterized in that the objects (2) are fed into the loading unit (4) in a continuous stream and leaves the compactor (30) one by one in a continuous stream compressed and / or punctured and / or crushed and are led into the collecting unit (3).

24. Use of the pneumatic conveying system (1) according to claims 1-15 for performing the method according to claims 16-22.

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