METHOD AND APPARATUS FOR TRANSFERRING BULK

Abstract: The invention relates to an apparatus intended for transferring bulk in a transfer step substantially in a single transfer direction (s) from a first point (I) to a second point (II). The bulk (1) to be transferred includes a transverse and rigid transmitting surface (2) and a connecting surface (3), providing a connection with transmitting surface (2) substantially through the interior of bulk (1), and the bulk is transferred or carried by means of a transfer mechanism (4), operating between first and second (I, II) points and including a contact element (5), rotating around its longitudinal axis (a) and provided with a first component (5a) located at a constant distance from its longitudinal axis (a), and a bearing surface (6), located in its longitudinal direction substantially parallel to transfer direction (s) and bearing said bulk (1) during the course of its transfer. Upon carrying bulk (1) by means of transfer mechanism (4) in accordance with the invention, its transmitting surface (2) in communication with said first component (5a) of contact element (5) in a manner that said first component (5a) extends through said connecting surface (3) substantially into the interior of bulk (1).

Description: Method and apparatus for transferring bulk The present invention relates to a method for trans¬ ferring bulk in a transfer step in a substantially single transfer direction from a first point, such as a supply or loading station or a like, to a second point, such as a delivery or unloading station or a like whereby, during the course of transfer, the bulk which includes at least one substantially transverse and rigid transmitting or contact surface and at least one connecting surface, such as at least a partially open, resilient or a like wall, providing a connection substantially to the interior of bulk, is carried by means of a transfer mechanism operating between the first and the second point and comprising at least a contact element and a bearing surface, such as a chute, a trough, a rail or a like, located at a certain distance from contact element and extend¬ ing in its longitudinal direction substantially parallel to transfer direction and bearing said bulk during the course of transfer, whereby said contact element is, upon rotating during the course of transfer around its said longitudinal axis extending parallel to the transfer direction, at least in a force-trans- mitting contact with the bulk, and which contact element includes a first component, extending in the transfer direction and located at a constant distance from its longitudinal axis. The method is particularly suitable for transferring empty cases, boxes or the like. Conventionally, the transfer of such articles has been effected by means of a belt conveyor, the articles placed on a belt conveyor being carried in a desired transfer direction and at a suitable speed from one point to another. Such articles are also transferred by the application of gravity, the article sliding on a running chute, such as a trough or a like, extending in an inclined direction. Furthermore, especially the transfer of smaller articles, or liquid or powdered materials, is effected by using a screw conveyor which can be adapted to operate at a transfer angle steeper than in the above solutions. A problem in the above type of solutions using a belt conveyor is that an article or bulk cannot be carried at very steep transfer angles. Conventionally, the transfer angle is not more than appr. 30-45°, depending of course on the bulk being carried and the type of belt being used. In addition, the use of belt conveyors generally requires more procedures dealing with installation and maintenance. The transfer of bulk solely by the application of gravity is in its simplicity an ideal solution, as articles can thus be transferred in vertical direction by using simple slide structures. A drawback in this type of method is, however, that the speed of an article being carried increases too much during the slide down a chute. Thus, upon stopping the article at an unloading point, it is necessary to employ damping mechanisms in order not to damage the goods. However, the application of such damping mechanisms is troublesome and, in addition, the article must usually be removed from a chute before the next one is slid down. The traveling speed of an article being transferred depends naturally on the mass of said article whereby, as the goods to be transferred are replaced with another type of goods having e.g. different specific weight or friction characteristics, the traveling speeds can thus be quite different from what is desired. In this case, the adjustment of traveling speed can be effected e.g. by altering the angle of inclination of a chute, which means, however, that the location of an unloading point will be changed. In practice, this type of "dropping chute" is not possible to design for very great transfer angles for the above reasons and, thus, the transfer of goods e.g. in a substantially or nearly vertical direction is not possible in practice. It is possible to apply the screw conveyor type solutions for carrying a wide variety of articles and materials. The screw conveyor comprises a spiral element rotating in a surrounding housing, the in- dividual articles, during the course of their transfer, being located between the internal housing surface and two successive spirals of the rotating element. The transfer of larger articles, such as empty cases or the like, cannot be effected by a screw conveyor technique operating on the above principle, since this would require a screw conveyor of unrealistic dimensions, regarding e.g. its outer diameter and pitch. Thus, screw conveyors are most generally used for carrying powdered or liquid materials. The object of a method of this invention is to provide a decisive improvement on the above drawbacks and, hence, to raise substantially the level of the existing prior art. In order to achieve this object, a method of the invention is primarily characterized in that the transfer of bulk lying on bearing surface is effected by subjecting at least one transmitting surface thereof, preferably its leading and/or trailing edge, to the action of the first component of contact element, extending through said connecting surface substantially into the interior of bulk. The most significant benefits offered by a method of the invention include simplicity and operating reliability so as to avoid operating shut-downs. A method of the invention offers also the advantage of facilitating the application of gravity. Thus, a method of the invention provides a possibility of effecting the transfer of bulk in substantially more transfer directions than in the prior known methods while saving self-operating energy. The other non-independent claims directed to a method disclose preferred applications for a method of the invention. The invention relates also to an apparatus for carrying out the method. The apparatus is defined in more detail in the preamble of the independent claim directed to an apparatus. The principal characterizing features of the apparatus are disclosed in the charac¬ terizing section of the same claim. An apparatus of the invention is capable of effecting the transfer of bulk from one location to another in a simple and reliable fashion. It is also possible to effect the transfer of bulk safely e.g. in a substan- tially vertical direction. Especially in the app¬ lication of gravity, the self-operating power required by an apparatus of the invention is substantially lower than that required by the currently used equip¬ ment. The non-independent claims directed to an apparatus disclose preferred embodiments for an apparatus of the invention. The invention will be described in detail in the following specification while reference is made to the accompanying drawings, in which fig. 1 shows a front view of an apparatus for applying a method of the invention, fig. 2 is a side view of the same apparatus, and fig. 3 shows a detail explaining the operating principle of the invention. An apparatus applying a method of the invention is intended for carrying bulk during the course of its transfer in a substantially single transfer direction s from a first point I, such as a supply or loading station or a like, to a second point II, such as a delivery or unloading station or a like. The bulk 1 being transferred includes at least one substantially transverse and rigid transmitting or contact surface 2, such as a leading or trailing edge 2a, 2b or a like, and at least one connecting surface 3, such as an open top surface 3a, providing a connection through the interior of bulk 1 to said transmitting surface 2, and it is carried by means of a transfer mechanism 4 operating between first and second points I, II. The transfer mechanism 4 includes a contact element 5, rotating around its longitudinal axis a, and a bearing surface 6, spaced at a certain distance from contact element 5 and extending in its longitudinal direction parallel to transfer direction s and suppor¬ ting the bulk 1 during the course of its transfer. The contact element 5 is in a force-transmitting contact with bulk 1 and includes a first component 5a, extending in transfer direction s and spaced at a constant distance from its longitudinal axis a. In order to carry bulk 1 during the course of its transfer by means of transfer mechanism 4 in accordance with the invention, its transmitting surface 2, such as leading edge 2b and/or trailing edge 2a, is adapted to be contacted by the first component 5a of contact element 5 in a manner that said first component 5a extends partially through the open top surface 3a serving as said connecting surface 3 substantially into the interior of bulk 1. In the preferred embodiment shown in figs. 1 and 2, the method has been applied in vertical direction, the movement of bulk 1 being controlled by means of a chute 6, serving as a bearing surface and including floor sections 6a and side sections 6b. Furthermore, in a preferred embodiment, the contact element 5 comprises a spiral tube, rod or a like 5a, serving substantially as said first component and arranged, as shown e.g. in fig. 3, in a force-transmitting contact with bulk 1 in a manner that the spiral component 5a is in contact with the edge portion of whichever transmitting surface 2a, 2b of bulk 1 is furthest away from bearing surface 6a. Fig. 3 illustrates the operating principle of the invention by showing a detail included in transfer mechanism 4. Thus, in order to carry bulk 1 in transfer mechanism 4 by means of contact element 5 and in order to achieve the movement of bulk 1 relative to bearing surface 6, the smallest distance e of the first component 5a of contact element 5 from bearing surface 6a is, on the one hand, substantially less than the greatest extent E of the transmitting surface 2a, 2b of bulk 1 being carried and, on the other hand, the outer diameter d of first component 5a is substantially less than the smallest clear width D of the connecting surface 3a of bulk 1. The above-de¬ scribed assembly is essentially different from conven- tional screw-conveyor systems in its operating prin¬ ciple. Thus, in its most simple form a method of the invention can be applied in a manner that the apparatus comprises operating elements 7, such as a brake or a like, reducing the gravitational traveling speed of bulk 1 for decelerating the rotating motion w of contact element 5 caused by the gravitational movement of bulk 1. In reference to figs. 2 and 3, the apparatus hence operates in a manner that the bulk 1 picked up at supply point I comes into contact with the spiral 5a of transfer mechanism 4 which, under the action of a contact force exerted by article 1 begins to rotate around its longitudinal axis a, as shown by w. Should the rotating motion of spiral 5a be nearly friction- less, said article 1 would be allowed nearly a free drop in chute 6. The action of the above-described brake 7 can be applied to adjust the rotating motion of spiral 5a by varying the braking force for obtaining a suitable transfer speed. By the application of conventional conveyor technology it is possible to fit the apparatus with transmission elements 8, such as a motor or a like with a variable rotating speed, for effecting on the rotating motion w of spiral 5a for maintaining and/or varying the traveling speed of bulk 1. Thus, an apparatus of the invention is characterized in that the spiral 5a applies the force action of motor 8 to the internal or external edge portion of transmitting surface 2a, 2b which is furthest away from the bearing surface 6 of bulk 1. In conventional screw conveyors, the force action is applied to the entire outer surface section of one transverse wall commencing substantially from the bearing surface. It is obvious that the invention is not limited to the above embodiments but it can be modified con¬ siderably within the scope of the basic concept due to the overall extent of the method and the apparatus for practicing it. Thus, the method can be applied e.g. in a substantially horizontal direction. In this case, the apparatus can be designed e.g. in a manner that the open wall of the bulk is located in the bottom, whereby the bulk travels on top of the contact element. Similarly, the bearing surface can be designed to be partially or entirely spiral in transfer direc¬ tion e.g. for unloading the bulk in a given direction. In addition, the first component of a contact element can be designed as a conventional screw, the outer edges of its threads being, however, rounded in view of minimizing their wearing action. However, an advantage gained by the described spiral design is a very lightweight construction obtained thereby, which makes it possible to minimize the self-operating power required by the apparatus. Naturally, the method can be applied to the transfer of most versatile types of goods, whereby the connecting surface can be partially made of a flexible screen, film or a like, facilitating the relative force action between the contact element and the transmitting surface. Of course the apparatus can also be automated whereby, e.g. for controlling the unloading actions, the bottom section of a transfer mechanism is provided e.g. with a light-operated sensor, which is connected to operat- ing elements and/or a transmission element for varying and/or interrupting the rotating motion of a contact element.

Claims: Claims : 1. A method for transferring bulk in a transfer step in a substantially single transfer direction (s) from a first point (I) , such as a supply or unloading station or a like, to a second point (II) , such as a delivery or unloading station or a like, whereby, during the course of transfer, the bulk (1) which includes at least one substantially transverse and rigid transmitting or contact surface (2) and at least one connecting surface (3), such as at least a partially open, resilient or like wall (3a) , providing a connection substantially to the interior of bulk (1) , is carried by means of a transfer mechanism (4) operating between first (I) and second (II) point and comprising at least a contact element (5) and a bearing surface (6) , such as a chute, a trough, a rail or a like, located at a certain distance from contact element (5) and extending in its longitudinal direction substantially parallel to transfer direction (s) and bearing said bulk (1) during the course of transfer, whereby said contact element (5) is, upon rotating during the course of transfer around its said lon¬ gitudinal axis (a) extending parallel to transfer direction (s) , at least in a force-transmitting contact with bulk (1) and which contact element (5) includes a first component (5a) , extending in transfer direction (s) and located at a constant distance from its longitudinal axis (a) , characterized in that the transfer of bulk (1) lying on bearing surface (6) is effected by subjecting at least one transmitting surface (2) thereof, preferably its leading and/or trailing edge (2a, 2b) , to the action of the first component (5a) of contact element (5) , extending through said connecting surface (3) substantially into the interior of bulk (1) . 2. A method as set forth in claim 1, characterized in that the transfer of bulk (1) is effected in a manner that the first component (5a) of a contact element, preferably a spiral, helical or a like rod, tube or a like, is in a force-transmitting contact with the edge portion or the like of the transmitting surface (2) of bulk (1) lying furthest away from a floor section (6a) of the bearing surface. 3. A method as set forth in claim 1 or 2, wherein the transfer mechanism (4) is at least partially adapted to operate in a position substantially different from horizontal, such as in an inclined, vertical or like position, and to make use of gravity, characterized in that the gravitational traveling speed of bulk (1) is at least reduced by means of operating elements (7) , such as a brake or a like, which are used for decelerating the rotating motion (w) of contact element (5) caused by the gravitational movement of bulk (1) . 4. A method as set forth in any of preceding claims 1-3, wherein the transfer mechanism (4) is at least partially adapted to operate by means of transmission elements (8) , preferably a motor or a like with a variable rotating speed, at least in a force-transmit¬ ting communication with contact element (5) for applying action on contact element (5) , such as on the speed of its rotating motion (w) or the like, for maintaining and/or varying the traveling speed of bulk (1) , characterized in that said first component (5a) of the contact element is used for applying the action of transmission elements (8) to the internal or external edge portion or the like of a transmitting surface, such as said leading and/or trailing edge (2a, 2b) , lying furthest away from a floor section (6a) of the bearing surface for bulk (1) . 5. An apparatus for transferring bulk in a transfer step substantially in a single transfer direction (s) from a first point (I) , such as a supply or loading station or a like, to a second point (II) , such as a delivery or unloading station or a like, whereby the bulk (1) , which includes at least one substantially transverse and rigid transmitting surface (2) and at least one connecting surface (3) , such as an at least partially open, resilient or a like wall (3a) , providing a connection substantially with the interior of bulk (1) , is adapted to be carried by means of a transfer mechanism (4) , operating between first and second (I, II) points and comprising at least a contact element (5) and a bearing surface (6) , such as a chute, a trough, a rail or a like, located at a certain distance from contact element (5) and extending similarly in its longitudinal direction substantially parallel to transfer direction (s) and bearing said bulk (1) during the course of its transfer, whereby the contact element (5) during the course of transfer is, upon rotating around its longitudinal axis (a) extending substantially parallel to said transfer direction (s) , at least in a force-transmitting contact with bulk (1) , and said contact element (5) being provided with a first component (5a) , extending in transfer direction (s) and located at a constant distance from its longitudinal axis (a) , characterized in that in said transfer mechanism (4) at least one transmitting surface (2) of bulk (1) , preferably the leading and/or trailing edge (2a, 2b) , is arranged in contact with the first component (5a) of contact element (5) in a manner that said first component (5a) extends through said connecting surface (3) substantially into the interior of bulk (1) . 6. An apparatus as set forth in claim 5, charac¬ terized in that in order to facilitate the movement of bulk (1) occurring relative to bearing surface (6) , the smallest distance (e) of the first component (5a) of contact element (5) from the bearing surface floor section (6a) is adapted to be substantially less than the greatest extent (E) of the transmitting surface (2a, 2b) of bulk (1) being transferred from the bearing surface floor section (6a) and the outer diameter (d) of first component (5a) is adapted to be substantially less than the smallest clear width (D) of the connecting surface, such as an open wall (3a) , included in bulk (1) . 7. An apparatus as set forth in claim 5 or 6, characterized in that the bulk (1) and at least the first component (5a) of contact element (5) , preferably a spiral, helical or similar rod, tube or a like, are arranged in transfer mechanism (4) in a force-trans¬ mitting contact with each other in a manner that said first component (5a) is in contact with the edge portion or the like of that transmitting surface (2) of bulk (1) which is furthest away from floor section (6a) of the bearing surface. 8. An apparatus as set forth in any of preceding claims 5-7, wherein the transfer mechanism (4) is at least partially adapted to operate in a position substantially different from horizontal, such as in an inclined, vertical or like position, and to make use of gravity, characterized in that the apparatus includes operating elements (7) , such as a brake or a like, for at least reducing the gravitational traveling speed of bulk (1) and used for decelerating the rotating motion (w) of contact element (5) caused by the gravitational movement of bulk (1) . 9. An apparatus as set forth in any of preceding claims 5-8, wherein the transfer mechanism (4) is at least partially adapted to operate by means of trans¬ mission elements (8) , preferably a motor or a like with a variable rotating speed, mounted in at least a force-transmitting communication with contact element (5) and adapted to apply action on contact element (5) , such as on the speed of its rotating motion (w) or the like, for maintaining and/or varying the traveling speed of bulk (1), characterized in that in said transfer mechanism (4) the first component (5a) of a contact element is adapted to apply the action of transmission elements (8) to that internal or external edge portion or the like of a transmitting surface, such as leading and/or trailing edge (2a, 2b) , which is furthest away from floor section (6a) of the bearing surface.

Inventors: MUSTAJAERVI HANNU, MUSTAJAERVI TUOMO, MUSTAJAERVI, HANNU, MUSTAJAERVI, TUOMO
Applicants: MUSTAJAERVI HANNU, MUSTAJAERVI TUOMO, MUSTAJAERVI, HANNU, MUSTAJAERVI, TUOMO
Application year: 1992
Main classification: B65G33
IPC codes: B65G33