A pneumatic pick up unit and a pneumatic conveyor system.

Prior art:

The present invention relates to pneumatic conveyor system in general and more specifically to a pneumatic pick up unit adapted for lifting multiple components by suction and transferring the components into a pneumatic conveyor tube system the pneumatic component pick up unit comprising a suction conveyor tube having an open end and an opposite end adapted to be connected to a conveyor tube of the pneumatic conveyor tube system.

Pneumatic pick up units of this type is known in the prior art for providing an efficient transfer of components or bulk ware from a bin and to a conveyor tube of the pneumatic conveyor system. The open end of the suction conveyor tube sucks the components or bulk ware into the suction conveyor tube where the flow of air further lifts the components or bulk ware through the suction conveyor tube and transfers it to and through a conveyor tube of the pneumatic conveyor system.

In most situations, ambient air is used for this purpose. In certain situations, however, it may be relevant to use other gasses for the same purposes and therefore in the following the term air shall be understood as covering air or any other suitable gas. An example of such a pneumatic pick up unit is known e.g. from GB patent no. 1412693 disclosing a pneumatic lifting device for transferring granular or powder abrasive material from a hopper to a blast nozzle.

In the prior art pneumatic conveyor systems and component pick up units have been used for many other applications including transferring more fragile components such as injection molded components from a large bin into smaller containers e.g. for packing or assembly.

Object of the invention:

On this background, it is the object of the present invention to provide a component pick up unit, as mentioned in the introduction, allowing also for conveying components that are even more fragile.

This is obtained by the invention as defined in present claim 1.

The use of a second suction tube having its suction opening arranged inside the suction conveyor tube at position between the open end and the opposite end provides the option of increasing the flow of air between the open end of the suction conveyor tube without simultaneously increasing the air speed in the conveyor tubes downstream from the suction opening inside the suction conveyor tube. This provides the option of lift components out of e.g. a bin using a relatively high air speed and thereafter convey the components at a lower speed through the conveyor tube.

In a preferred embodiment, the suction opening of the second suction tube is positioned near the open end of the suction conveyor tube in order to reduce the distance in the suction conveyor tube where the components are conveyed with a high velocity.

In order to avoid components entering into the second suction tube via the suction opening the suction opening is advantageously covered by a grating.

The suction conveyor may be a flexible tube and may even be handled manually by an operator. In a preferred embodiment, however, the tube is formed as a telescopic tube having a upstream conveyor tube comprising the open end and an downstream conveyor tube comprising the opposite end, and the upstream conveyor tube and the downstream conveyor tube are slidable with respect to each other.

The downstream conveyor tube may in this relation be suspended from a support structure via a bracket allowing at least the open end of the conveyor suction tube to move horizontally in all directions.

Thereby it is possible to move the open end of the suction conveyor tube upwardly and downwardly and to any side, so that it can sweep over a large area for sucking up components e.g. in a large bin.

In this relation, the bracket is advantageously a universal joint, allowing the suction conveyor tube to rotate about two substantially orthogonal axes of rotation and thereby the open end of the conveyor suction tube to swing horizontally in all directions.

Furthermore at least one actuator may advantageously be arranged for moving the open end in a predetermined pattern, and another actuator be arranged be arranged for changing the length of the telescopic conveyor tube. In a preferred embodiment, the suction tube extends outside the suction conveyor tube.

In a further preferred embodiment, the suction opening is arranged in the tubular wall of the suction conveyor tube.

An especially compact construction is achieved by arranging at least a section of the suction conveyor tube inside the second suction tube.

The present invention also relates to a pneumatic conveyor system comprising a pneumatic conveyor tube and a blower adapted for providing a flow of air through the pneumatic conveyor tube, and wherein the pneumatic conveyor system comprises a component pick up unit as mentioned above.

In this relation the pneumatic conveyor system may advantageously further comprise a blower for providing a flow of air into the second suction tube through the suction opening.

The drawing:

Figure 1 : Is a drawing showing the layout of a pneumatic conveyor system comprising a component pick up unit according to the invention.

Figure 2: Shows a cross section of the open end of the component pick up unit shown in figure 1.

Figure 3: Is a principle drawing showing the working principle of an embodiment of the invention. Description of an embodiment of the invention:

Figure 1 shows a layout of one embodiment of a pneumatic conveyor system 1 with a component pick up unit 7 according to the invention. This system is designed for transferring components from the large octagonal bin 8 into a number of smaller boxes 2.

In this layout, suction is provided by the blower 3 via a suction pipe 4 to a component vacuum loader 5 adapted for separating the airflow from the components conveyed by the flow of air through the pneumatic conveyor tube 6. The components are transferred into the pneumatic conveyor tube 6 via the component pick up unit 7 that lifts the components out of the octagonal bin 8 by suction and further transfers the components from the component pick up unit into the pneumatic conveyor tube 6.

For this purpose, the octagonal bin 8 is positioned next to the component pick up unit 7 under the open end 11 of the suction conveyor 12. The suction conveyor 12 is connected at its opposite end 13 to the pneumatic conveyor tube 6 so that the components in the octagonal bin can be lifted by the flow of air provided by the blower 1 .

In this embodiment the suction conveyor 12 have a upstream conveyor tube 14 telescopically connected to an downstream conveyor tube 15 so that the length of the suction conveyor tube 12 can be changed in order to reach different levels of components present in the octagonal bin 8. In order to avoid bridging of components in the octagonal bin 8 or in order to reduce the necessary air speed for lifting the components from the octagonal bin 8 the downstream conveyor tube 15 is suspended from the supporting structure of the component pick up unit 7 via a universal joint bracket 16. This provides that the suction conveyor 12 can swing about two substantially orthogonal axes 17, 18, so that the open end 11 of the suction conveyor 12 can sweep over and in a safe distance above the components in the octagonal bin 8.

According to the principle of the invention, the component pick up unit 7 comprises a suction conveyor tube 19 and a second suction tube 20 having an opening inside the suction conveyor tube 19. In the embodiment shown in figure 2 the suction conveyor tube 19 and the second suction tube 20 are established using two concentric tubes with the suction conveyor tube 19 arranged inside the second suction tube 20. A grating 21 is made in the wall of the suction conveyor tube 19 forming the opening into the second suction tube 20.

As both the suction conveyor tube 19 and the second suction tube 20 are connected to a suction blower 1 , then the flow of air 22 that is necessary for lifting components out of the bin 8 is divided into two air streams 23, 24 as shown in figure 2.

Only one of the air streams 23 further conveys the components to the pneumatic conveyor tube 6 as shown in figure 1 . The speed of this air stream 23 is therefore significantly reduced with respect to the air stream 22 necessary for lifting the components out of the bin 8, and thereby the components are conveyed through the pneumatic conveyor tube at a relatively reduced speed. Figure 3 illustrates the working principle of the embodiment of the invention as shown in figure 1 . Here the open end 11 of the suction conveyor 12 is caused first to sweep in substantial horizontal directions along the path 25 and then to move downwards along the line 26 hereafter it is again caused to sweep in horizontal directions along the path 25’. This working principle may be used with any type of component pick up unit and it is established in this embodiment by the bracket 16 and the telescopically suction conveyor 12, and a number of actuators that are not shown in the drawings for clarity reasons.