EP0039332A1

EP0039332A1 - Conveyor

Info

Publication number: EP0039332A1
Application number: EP19800901423
Authority: EP
Inventors: Ulf Henreksen
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-07-18
Filing date: 1980-07-16
Publication date: 1981-11-11
Also published as: GB2077685B; WO1981000244A1; GB2077685A

Abstract

Transporteuse comprenant d'une part une chaine de plusieurs maillons (1) de preference en materiau plastique et relies les uns aux autres au moyen d'articulations de preference du type a joint universel, lesquelles articulations possedent des axes (9) s'etendant transversalement a la chaine, et d'autre part des moyens de guidage (2) ayant des surfaces de coulissement, dont font partie des surfaces de coulissement portant la charge et regardant vers le haut (25), le long desquelles les maillons sont disposes pour se deplacer sous l'action de forces de traction transmises entre les maillons via lesdites articulations, les maillons etant concus pour porter et transporter des marchandises et presentant d'une part des surfaces portant les marchandises (7) et d'autre part des surfaces de coulissement (27, 45, 47), disposees pour cooperer avec les surfaces de coulissement des moyens de guidage. Chaque maillon (1) est divise d'une part en un premier composant (3) pourvu de l'articulation (5) du maillon et d'autre part en un second composant (4) concu sous forme d'unite separee qui, a l'aide de moyens d'attache peut etre assujetti de maniere detachable au premier composant et possede des portions de projection (41) qui s'etendent sur les cotes exterieurs des parties laterales du premier composant respectif (3), entre lesquelles l'articulation (5) de ce composant est placee de maniere telle que lesdits axes (9) obtiennent un support contre lesdites portions (41) du second composant de maniere que l'axe soit maintenu en position en meme temps que ses extremites sont protegees du contact avec les moyens de guidage (2).Conveyor comprising on the one hand a chain of several links (1) preferably made of plastic material and connected to each other by means of articulations preferably of the universal joint type, which articulations have axes (9) extending transversely to the chain, and on the other hand guide means (2) having sliding surfaces, of which part of the sliding surfaces carrying the load and looking upwards (25), along which the links are arranged to displacing under the action of tensile forces transmitted between the links via said articulations, the links being designed to carry and transport goods and having on the one hand surfaces carrying the goods (7) and on the other sliding surfaces (27, 45, 47), arranged to cooperate with the sliding surfaces of the guide means. Each link (1) is divided on the one hand into a first component (3) provided with the articulation (5) of the link and on the other hand into a second component (4) designed in the form of a separate unit which, by means of fastening means can be detachably secured to the first component and has projection portions (41) which extend over the external dimensions of the lateral parts of the respective first component (3), between which the articulation (5) of this component is placed in such a way that said pins (9) obtain a support against said portions (41) of the second component so that the pin is held in position at the same time as its ends are protected from contact with the guide means (2).

Description

Title: Conveyor

Technical field: The invention refers to conveyors comprising a chain of a num¬ ber of links connected with each other by means of articulations pre¬ ferably of universal joint type, which articulations exhibit pivot pins extending in transverse direction across the chain, and a guiding means exhibiting sliding surfaces , of which upwards facing load- carrying sliding surfaces form part, along which the links are pro¬ vided to displace themselves under the actuation of pulling forces, which are transmitted between the links via said articulations . The links being arranged to carry and transport goods and exhibiting for one thing goods-carrying srufaces and for another thing sliding surfaces , which are arranged to cooperate with the sliding surfaces of the guiding means .

Background:

A conveyor of known type is composed of a series of links, which are connected with each other by means of universal joints , its transporting and goods-carrying function being combined in a single component of each link at the same time as the links are pro¬ vided to slide with their undersides against a load- supporting sliding surface in a guiding means , along which the chain of links is arranged to run while transporting the goods . Conveyor chains of this type are generally made of plastic material as the links will be comparatively bulky and complicated. However, in order to connect the links , pivot pins of relatively thin cross-section are required, which therefore have to be made of metal, usually of steel. It has turned out that this results in an unfavourable combination of mate¬ rials , as the pivot pins tend to extricate themselves from the mate¬ rial, and they will thereby impede the function of the conveyor by scraping against the sliding surfaces of the guiding means . This also gives rise to wear and damage . It has also turned out that links of the said type during the use are subjected to a wear, which reduces the tensional strength of the chain, as the wear brings about a waste of material causing a reduction of the cross-section of the pulling portion of the links intended to carry the tractive forces, to which the chain is subjected.

Tehcnical problem: In the type of conveyor mentioned and also in similar conveyors made of a chain of plastic components with articulations, of which pivot pins form part of the assembly, problems arise because of the fact that the materials, of which they are made, are unsuitable in certain functional respects, which results in an unnormal wear and functional deficiences. Said problems are accentuated by the choice of material for the links according to the known design necessarily being a compromise between the demand for a strong tensile strength ^"of the pulling component and a low friction of the sliding surfaces. As a matter of fact said requirements are in certain cases conflicting, as a suitable material exhibiting a good tensile strength, such as reinforced material like plastic reinforced with fibre-glass, often exhibits a high friction in the sliding surfaces .

The solution: The solution indicated by the invention involves the dividing up of the links in a pulling component, by means of which the pul¬ ling forces are transmitted via the joints, and a goods -carrying com¬ ponent, which is provided as a separate unit and in such a manner that it can lock the shaft pivots at the same time as it is provided to form at least certain sliding surfaces of the link.

Advantages :

Thus , it is an object of the present invention to provide a con¬ veyor, which does not exhibit the drawbacks mentioned above, but in which said problems are eliminated. By means of the invention it is , thus , possible to design each link in such a way that it will exhibit a good tensional strength, which independent of time will be maintained in the components subject to pulling forces , and this at the same time as the friction of the sliding surfaces of the link will be low.

Any problem in connection with the holding the pivot pins in place vfϋl also be eliminated by means of the invention. Brief description of drawings:

The invention will now be described in ore detail in the follo¬ wing by means of an example of embodiment, reference being made to the accompanying drawings, in which Fig. 1 is a view as seen from the underside showing the shape of a link of the universal joint type forming part of a conveyor and its coupling to an adjacent link, Fig. 2 is a partial cross-sectional view of the link according to Fig. 1 along the line II-II of this figure, Fig. 3 is a top view, Fig. 4 a side-elevational view, and Fig. 5 a front view of a pulling component °f the link in non-coupled condition. Fig. 6 is a view as seen from above showing a goods-carrying portion forming part of the univer¬ sal joint, whereas Fig. 7 is a side-elevational view, and Fig. 8 a front view of the goods-carrying portion, Fig. 9 is a partly broken cross-sectional view through a portion of the link, ^• Fig. 10 shows the cooperation of the universal joint links with a gear forming part of the conveyor, and Fig. 11 is one half of a cross-sectional view through a guiding means forming part of the conveyor.

Best mode of carrying out the invention: The conveyor according to the invention is formed of an end¬ less chain of a series of a great number of universal joint links 1 , _^which are illustrated by means of an example in Fig. 1 , and a gui¬ ding means 2 along which the chain of links is arranged to run in order to carry and transport goods along a predetermined path. The guiding means is shown by means of an example in Fig. 11, which will be described more in detail below. Each universal joint 1 accor¬ ding to the invention comprises two separate main components, vi2. a pulling component 3 and a goods-carrying component 4, which latter one for simplicity's sake will be called goods-carrier. It is assumed that the components of the chain are made of plastic material, which is common in connection with this type of conveyors . The pulling component 3 of each link 1 is arranged to transmit the puUing forces , which shall be applied to the chain of links in order to bring about the displacement of goods by means of the conveyor. The links are coupled together with each other by means of a universal joint 5, which forms part of each link and permits that the links are in between them articulated round two pivoting axles at right angle to

OMPI each other. Two legs 6 extend from the universal joint 5 in the longitudinal direction of the chain and substantially diverge in direction away from the universal joint. As is best evident from Fig. 3, the pulling component 3 exhibits a bar 21 extending cross- wise between the legs 6. Said legs 6 exhibit each one its slit 39 of long extension, which forms an opening for the insertion of a shaft 9 into the universal joint. The shaft 9 is of relatively small cross- section and must therefore be made of metal. Said shaft is connected with each one of the legs 6 by extending through a hole 10 in the outer end 42 of each respective leg. There are in addition holding means in the form of openings 38 for the goods-carrier 4. The slits 39 can be designed with a still longer extension and can be connecte with the openings 38 in order to reduce the weight and the consump¬ tion of material for the pulling component 3, which in spite thereof does not result in any impaired tensional strength for this component as the tensional strength is determined by the smallest cross-sectiona area of the material, i.e. the cross-sectional area at the necessary opening for the insertion of the shaft.

Each leg exhibits on its outside notches 40 intended to receive downwards pointing portions 41 of the goods-carrier 4. In the illu¬ strated example the notches 40 have a depth corresponding to the thickness - of the downwards pointing p^'ortions , whereby in the mounted condition of the universal joint link 1 said portions together with surface portions 42, 43 on the outside of the legs 6 form a smooth and substantially plane contact surface, which will be de¬ scribed more in detail below.

The universal joint is substantially formed of dowel 12 pivoted in one end of the pulling component, the shape of which dowel is best evident from Figs . 1 and 10. The shaft 9, thus , extends through this dowel, whereas the other shaft of the universal joint is formed of the dowel itself, as it can be pivoted round its own central axis and cooperates with an inwards facing cylindric bearing 13 of the pulling component. This bearing 13 is formed of a wall 35, which is rounded-off on its outside and blends into the two legs 6. This wall 35 defines a substantially cylindric space, in which the dowel 12 is pivoted. As is evident from Fig. 10 the dowel 12 also exhibits a second curved surface 14, the centre of curvature of

OMP which coincides with the shaft 9. Its function will be described more in detail below. i

As is evident from Figs . 6, 7, and 8 the goods -carrier 4 in the example shown comprises a platformlike element with a surface r 7, which is intended to support the goods in the form of different objects . The underside of the portion forming the surface 7 forms a sliding surface 27 for the support of the link in the guiding means 2. The goods-carrier 4 can be detachably attached to the pulling component 3 by means of fastening means, which in the example _Q shown comprise two fastening elements 18 pointing downwards from the underside 27 of the goods-carrier 4, said elements 18 exhibiting a hooking means 19. As is best evident from Fig. 9 the fastening elements 18 are designed in such a manner that they can engage an edge 20 of the openings 38 of the putting component 3 by means of

■J its hooking means 19. The goods-carrier is effectively held to the traction component 3, but it can be easily detached, as the fastening elements 18 are made of a somewhat yielding material, by way of example plastics, so that the hookshaped elements 19 can be made to springingly yield in order to detach the goods -carrier. The goods-

2o carrier can by this arrangement easily be exchanged for goods- carriers of other design in order to make possible an adaptation of the conveyor to different types of goods. The goods-carrier can for example exhibit the shape of a container for the transportation of smaller units . From the manner, in which the goods-carrier 4 is held,

2 and from its design according to the example illustrated it is evident that the goods -carrier in mounted condition closes one end of the universal joint 5.

The goods -carrier 4 is provided with outwards pointing wings 44. As is evident from Figs . 7 and 8 said wings are located in the

30 lower portion of the downwards pointing portions 41 of the goods- carrier and project sideways from them . In addition to a convex sli¬ ding surface 45 the wings on their underside exhibit a somewhat chamfered front edge in order to facilitate a smooth running in the guiding means belonging to the conveyor equipment and to avoid lateral scraping.

35

By said wings 44 being provided as an integrated part of the goods-carrier 4 it is possible to choose a material of low friction for all sliding surfaces of the universal joint link 1, viz. the sliding surfaces 27 of the underside of the goods-carrier, which is μtilized in the direction of transportation, the sliding surface 45 of the wings 44, which is utilized in the return movement of the universal joint links in the manner described above, and a sliding surface 47 on the outside of the downwards pointing portions 41 of the goods- carrier, which is operative in curved sections, as is evident from Fig. 1. As mentioned above, the material for the pulling component 3 can, thus, in a high degree be based on the requirements of strength, a fibreglass reinforced thermoplastic polyester resin for example being chosen for the pulling component because of its good tensile strength.

As is also evident from Fig. 1 the surface formed by the two surface portions 42, 43 and the sliding surface 47 of the downwards pointing portion 41 occupies an oblique position relative to the longi¬ tudinal extension of the universal joint link, which results in a fa¬ vourable geometric feature in curved sections . As a matter of fact said common surface substantially forms the tangent to the arch 48 of the curved section in question, the tangential point substantially falling centrally on the sliding surface 47, which after some time of use at least partially acquires a slightly concave shape, whereby a favourable surface contact is obtained. As is further evident from Figs . 1 and 2, the downwards pointing portions 41 lock the shaft 9 in axial direction, as the portions 41 are located right in front of the two ends 49 of the shaft. Said ends 49 with a rounded-off por-_ tion extend somewhat outside the contour of the legs 6, whereas the downwards pointing portions 41 on the one side of them facing the legs exhibit a corresponding cut-out portion 50, which is in such a position that in the mounted condition of the universal joint link it is located right in front of the ends 49 of the shaft 9. As the down¬ wards pointing portions 41 are made of a material, which at least exhibits some resilient properties , a snap-in effect between the two ends 49 of the shaft 9 and the cut-out portions 50 is obtained, whereby the goods-carrier 4 is held still firmer resulting in an in- creased stability of the same.

As mentioned above, the chain of universal joint links is intended to run in a guiding means 2, the chain suitably forming a closed loop with a return section for the return travel of the links after the transported goods have been delivered. The guiding means 2 illustrated in Fig. 11 comprises an extruded profile made of for example aluminum and exhibiting for one thing a longitudinally exten- ding space 23 serving the purpose to receive the links 3 during their travel in the delivering direction, and for another ting a longitudi¬ nally extending space 24 arranged to receive the links during their return travel. Load carrying surfaces 25 are further incorporated in the profile by longitudinal running strips 26 being laid-in in the profile, which strips are made of a suitable wear-resistant material of low friction, by way of example of a suitably chosen quality of plastics, such as acetaldehyde resin . The goods-carrier 4 according to the invention on its underside exhibits said sliding surfaces 27, which are arranged to directly bear against the load carrying sliding surfaces 25 of the guiding means 2. By this arrangement the traction component 3 of the link will be relieved from a pressure exercising load of the goods , and will substantially only be subjected to tension loads, which is particularly advantageous for the service life of the links . In the return path of the conveyor there are likewise sliding surfaces 28 in the form of longitudinally extending running strips 29, against which the wings 44 of the links are arranged to slide with their somewhat convex sliding surface 45. When this is taking place, the links will bear against the sliding surfaces 28 of the re- turn path with their own weight only. The guiding means 2 further exhibits a chute 36 on each side, by means of which the conveyor can be mounted to a wall, to a frame or similar. In such connection the chutes 36 are provided to receive sideways extending pins, led¬ ges or similar. As the traction component 3, thus , is formed as an individual piece separated from the goods-carrier 4, both these main parts can be made of different material, each one especially adapted to the special requirements of the respective part, as mentioned above. The traction component can be made of a reinforced material, by way of example fibreglass reinforced thermoplastic polyester resin, which possesses a high tensile strength, but gives rise to high friction , whereas the goods-carrier 4 can be made of a material,, the

\ surface of which can be made to cause a low friction. In certain app lications a low friction may also be desirable on the top side of the goods-carrier, by way of example when goods are collected by mean of an element that retains the goods during the travelling movement of the conveyor.

In Fig. 10 the object of the arched surface 14 of the dowel 12 is shown, which is intended to cooperate with gears 33 of a gear pinion 34, which occupies a position at each end of the guiding mea 2. By one gear pinion being coupled to a driving motor, the neces- sary driving force for the transportation movement of the conveyor is obtained. Because of the universal joint of the links the conveyor can be straight or exhibit curved sections by providing the guiding means with the necessary curvature, which, thus, can be sideways directed bends as well as changes in the inclination of the conveyor. The present chain of universal joint links can, thus, be bent in two planes, in which respect it differs from most other driving chains .

The invention is not limited to the example of embodiment de¬ scribed above and illustrated in the drawings , but can be varied within the scope of the following claims . Even if it is especially well adapted for chains of universal joint links of the kind described, it can also be imagined to find an application in connection with other conveyor chains . The goods -carriers 4 can by way of example be designed in a completely different way, and the same goes for its fastening means . The legs 6 can further be differently designed wit respect to certain details . It is not necessary to make all sliding surfaces of the link on the goods-carrier, as certain sliding surfaces can be made on the traction component, by way of example surfaces subjected to less load such as the slidning surface for the return movement. Instead of the wings 44 being provided on the goods- carrying component, such wings can then be designed on the tractio component. The guiding means can be designed in a different manne by way of example in the form of bent sheet plate profiles.

"BU RE OMPI

Claims

Claims :

1. Conveyor comprising for one thing a chain of a number of links

(1) preferably made of plastic material and connected to each other by means of articulations (5) preferably of universal joint type, which articulations exhibit shaft pins (9) extending in transverse direction across the chain, and for another thing a guiding means

(2) exhibiting sliding surfaces , of which upwards facing load-carrying sliding surfaces (25) form part, along which the links are arranged to displace themselves under the actuation of pulling forces , which are transmitted between the links via said articulations, the links being arranged to carry and transport goods and exhibiting for one thing goods-carrying surfaces (7) and for another thing sliding sur¬ faces (27, 45, 47) , which are arranged to cooperate with the sliding surfaces of the guiding means, CHARACTERIZED BY that each link (1) being divided up in a first component (3) , which is provided with the articulation (5) of the link, and a second component (4) , which is designed as a separate unit, which by means of fastening means (18 - 20) can be detachably attached to the fist component and exhibits projecting portions (41) , which extend over the out- sides of the lateral portions of the respective first component (3) , between which the articulation (5) of this component is placed, in such a manner that said shaft (9) obtains a support against said portions (41) of the second component, so that the shaft is retained in position at the same time as its ends are protected from contact with the guiding means (2) .

2. Conveyor according to claim 1, CHARACTERIZED BY that the first component (3) of the chain link (1) being arranged to transmit the pulling forces via the articulations (5) and being arranged in the first place to take up traction forces and to substantially occupy a position at a distance from the sliding surfaces (25, 28) of the guiding means (2) , whereas the second component (4) is substantially relieved of traction forces and arranged to form the sliding surfaces (27, 45, 47) of the link for its support and guide in the guiding means (2) .

3. Conveyor according to claim 2, CHARACTERIZED BY that the outside (47) of said projecting portions (41) of the second component (4) being arranged to serve the purpose of a sliding surface relative to corresponding sliding surfaces of the guiding means and thereby guide the chain in sideways direction.

4. Conveyor according to claim 2 or 3, CHARACTERIZED BY that the second component (4) of the link being arranged to carry the goods and exhibiting an upper portion with a top side (7), which is arranged to carry the goods, and an underside, which exhibits a sliding surface (27) arranged to cooperate with the upwards facing sliding surfaces (25) of the guiding means (2), so that the load of the goods is transmitted to the guiding means exclusively via the gcκ>ds-carrying component substantially without any load on the traction component (3) .

5. Conveyor according to claims 2, 3 and 4, in which the chain (1, 3) is forming a loop and the guiding means (2) exhibits a return path with sliding surfaces (28) for return travelling links (1), CHARACTERIZED BY that said projecting portions (41) of the goods- carrying component (4) of the link (1) at their outer end opposite the goods-carrying portion (7) exhibiting sideways projecting winglik portions (44) , which form sliding surfaces (45) for the support of the link during its return travel, its main portion hanging down from said winglike portions (44) .

6. Conveyor according to anyone of the preceeding claims, CHARACTERIZED BY that each one of the projecting portions (41) exhibiting a cut-out portion (50) , into which the end (49) of said shaft (9) is arranged to penetrate.

7. Conveyor according to anyone of the preceeding claims, CHARACTERIZED BY that said fastening means (18 - 22) has the form of two fastening elements (18) projecting from the second com¬ ponent (4) and being arranged to grip around an edge (20) of a notch (38) or of another cut-out portion (38) of the first component (3) .

OMP