WO2005080237A1

WO2005080237A1 - Unit for conveying products

Info

Publication number: WO2005080237A1
Application number: PCT/EP2005/050716
Authority: WO
Inventors: Fulvio Boldrini
Original assignee: Azionaria Costruzioni Macchine Automatiche A.C.M.A. S.P.A.
Priority date: 2004-02-19
Filing date: 2005-02-18
Publication date: 2005-09-01
Also published as: ITBO20040084A1

Abstract

A unit (1) for conveying products (2), wherein a succession of products (2) is fed, on a belt (4) of a first conveyor (3), along a horizontal first path (P), and is transferred to a second conveyor (16) having a number of gripping heads (18), which are movable along a horizontal second path extending over a portion of the belt (4) and through a transfer station (19) for transferring the products (2) from the first (3) to the second (16) conveyor, are fixed with respect to the second conveyor (16), and provide for retaining respective products (2); and wherein a pusher (21) is located beneath the portion of the belt (4), at the transfer station (19), and deforms the portion of the belt (4) upwards to feed each product (2) to a respective gripping head (18).

Description

UNIT FOR CONVEYING PRODUCTS

TECHNICAL FIELD The present invention relates to a unit for conveying products . More specifically, the present invention relates to a unit for conveying products, the unit comprising a first and a second conveyor for said products, the first conveyor comprising a belt movable along a substantially horizontal first path; and the second conveyor comprising a number of gripping heads for retaining respective products, and which are movable with the second conveyor along a substantially horizontal second path extending over at least one portion of said belt and through a transfer station for transferring the products from the first to the second conveyor. BACKGROUND ART In known units of the type described above, the gripping heads are normally suction gripping heads which, in addition to moving along the second path, are each also lowered selectively to pick up a respective product advanced by the belt and located at the time beneath the gripping head. Being activated independently of the others, each gripping head must obviously have a respective actuator and, normally, a respective position sensor. Which, of course, seriously complicates the structure, and so reduces the dependability, of the second conveyor. DISCLOSURE OF INVENTION It is an object of the present invention to provide a unit for conveying products, designed to maintain as straightforward a structure of the conveyors as possible, while at the same time being cheap to produce. According to the present invention, there is provided a unit for conveying products, as claimed in Claim 1 and, preferably, in any one of the following Claims depending directly or indirectlyδon Claim 1. BRIEF DESCRIPTION OF THE DRAWINGS A number of non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, in which: Figure 1 shows a schematic partial side view of a first preferred embodiment of the unit according to the present invention; Figure 2 shows a larger-scale view of a detail in Figure 1; Figure 3 shows a schematic partial side view of a second preferred embodiment of the unit according to the present invention; Figure 4 shows a larger-scale, partly sectioned detail of Figure 3; Figure 5 shows a section along line V-V in Figure 3. BEST MODE FOR CARRYING OUT THE IWENTION Number 1 in Figure 1 indicates as a whole a unit for conveying products 2. Unit 1 comprises a powered conveyor 3, in turn comprising a belt 4, which is looped about two pulleys 5 and 6 rotating clockwise (in Figure 1) in steps about respective axes 7 and 8, and comprises a substantially horizontal top conveying branch 9 and a bottom return branch 10. Unit 1 also comprises a transfer assembly 11 for transferring products 2 - fed successively by belt 4 along a linear path P coincident with conveying branch 9 - to a horizontal top conveying branch 12 of an output conveyor 13 comprising a belt 14 looped about a number of guide pulleys 15. Transfer assembly 11 comprises a powered horizontal conveyor 16 located, on one side, over an output portion of conveying branch 9, and, on the other side, over an input portion of conveying, branch 12. Gripping devices 17 are fitted rigidly to conveyor 16, are equally spaced along conveyor 16, and comprise respective suction gripping heads 18 which are fixed with respect to relative gripping devices 17 and conveyor 16. Gripping devices 17 move in steps, together with conveyor 16, along an endless path, which overlaps conveying branch 9 at a transfer station 19 for transferring products 2 from conveyor 3 to conveyor 16, and overlaps conveying branch 12 at an unloading station 20 for unloading products 2 onto output conveyor 13. At transfer station 19, a pusher 21 is located beneath conveying branch 9, forms part of transfer assembly 11, and comprises a linear actuator 22 having an output pad 23, which is movable vertically, through path P, between a lowered rest position, in which pad 23 is located beneath a bottom surface 24 of conveying branch 9, and a raised work position, in which pad 23 is positioned contacting bottom surface 24 and upwardly deforms, towards conveyor 16, the portion of conveying branch 9 located at the time at transfer station 1 . Finally, unit 1 comprises a control circuit 25, in turn comprising a central control unit 26, which activates pusher 21, with a given delay, in response to product 2 presence signal emitted by a photocell 27 located upstream from transfer station 19. In a different embodiment (not shown) , photocell 27 is replaced by an angular sensor (encoder) located on pulley 5 or 6. In actual use, on entering transfer station 19, a product 2 is raised by pusher 21, together with a relative portion of conveying branch 9, onto a relative gripping head 18 travelling through transfer station 19 in time with product 2, and which can thus remove product 2 without performing any movement to and from conveying branch 9. Similarly, gripping head 18 need perform no vertical movement at unloading station 20 either, but simply releases product 2 onto conveying branch 12 of output conveyor 13. In other words, gripping devices 17 are simplified devices which are activated and deactivated to retain and release respective products 2, but perform no vertical approach movement. This therefore provides for greatly simplifying conveyor 16, as well as for reducing the forces applied to products 2 by relative gripping heads 18 when transferring products 2 from conveyor 3 to conveyor 16. In the Figure 3 embodiment, conveyor 3 is associated with a further powered conveyor 28 comprising a chain 29, which is looped about two pulleys 30 (only one shown) rotating about respective axes 31 parallel to axes 7 and

<&* 8, and comprises a substantially horizontal conveying branch 32 extending beneath and parallel to a central portion of conveying branch 9 upstream from transfer station 19. Chain 29 is fitted rigidly with a number of conveying pockets 33 spaced along chain 29 with the same * spacing with which products 2 are fed onto conveying branch 9. As shown more clearly in Figures 4 and 5, each pocket 33 is substantially U-shaped, is positioned with its concavity facing outwards of chain 29, and comprises two longitudinal lateral walls 34 located on opposite sides of chain 29 and extending outwards of chain 29 from a bottom wall 35. Bottom wall 35 has a central longitudinal groove 36 of a width and height equal to but no less than the width and height of belt 4, and of a width smaller than the width of bottom wall 35 and products 2. Longitudinal groove 36 of each pocket 33 along conveying branch 32 is engaged loosely by a relative portion of belt 4, which, as opposed to engaging relative product 2, leaves the product resting on the portions of bottom wall 35 on either side of longitudinal groove 36. In actual use, pockets 33 along conveying branch 32 lift relative products 2 off conveying branch 9, feed relative products 2 along the whole of conveying branch 32, while at the same time keeping products 2 equally spaced perfectly, and eventually release relative products 2 onto conveying branch 9 immediately upstream from transfer station 19.

Claims

1) A unit for conveying products (2), the unit (1) comprising a first and a second conveyor (3, 16) for said products

(2) , the first conveyor

(3) comprising a belt (4) movable along a substantially horizontal first path (P) ; and the second conveyor (16) having a number of gripping heads (18) for retaining respective products (2) and which are movable with the second conveyor (16) along a second path extending over at least one portion of said belt (4) and through a transfer station (19) for transferring the products (2) from the first to the second conveyor (3, 16); the unit (1) being characterized in that said gripping heads (18) are fixed with respect to said second conveyor (16) ; and that intermittent push means (21) are provided beneath said portion of the belt

(4) and at said transfer station (19) , to deform said portion of the belt (4) upwards towards said second conveyor (16) . 2) A unit as claimed in Claim 1, wherein said gripping heads (18) are suction gripping heads. 3) A unit as claimed in Claim 1 or 2, wherein said push means (21) comprise a pad (23) , and a linear actuator (22) connected to said pad (23) to move the pad (23) vertically through said first path (P) between a lowered rest position and a raised work position. 4) A unit as claimed in Claim 3, wherein said lowered rest position is a position of non-interference of said pad (23) with said belt (4) . 5) A unit as claimed in one of the foregoing Claims, wherein said first conveyor (3) comprises two pulleys (5, 6) defining, on said belt (4) , a conveying branch (9) and a return branch (10); the conveying branch (9) defining said first path (P) . 6) A unit as claimed in one of Claims 3 to 5, and also comprising control means (25) for activating said linear actuator (22) in time with said products (2) and the relative said gripping heads (18) . 7) A unit as claimed in Claim 5 or 6, and also comprising a third conveyor (28) having a conveying branch (32) located beneath and along a portion of the conveying branch (9) of said first conveyor (3) upstream from said transfer station (19) ; said third conveyor (28) comprising an endless flexible member (29) , and a number of pockets (33) connected to said flexible member (29) and equally spaced along the flexible member (29) ; and each pocket (33) along the conveying branch (32) of said third conveyor (28) being engaged by said belt (4), and supporting a respective said product (2) raised with respect to the belt (4) . 8) A unit as claimed in Claim 7, wherein each said pocket (33) is substantially U-shaped, is positioned with its concavity facing outwards of the endless said flexible member (29) , and comprises a bottom wall (35) ; and two longitudinal lateral walls (34) , which are located on opposite sides of the endless said flexible member (29) , extend outwards of the endless said flexible member (29) and parallel to said belt (4) from said bottom wall (35) , which comprises a central longitudinal groove (36) of a width and height equal to but no less than the width and height of the belt (4) . 9) A unit as claimed in Claim 8, wherein the endless said flexible member (29) is defined by a chain. 10) A unit as claimed in one of the foregoing Claims, wherein said second path is a substantially horizontal path.