A CONVEYOR CHAIN WITH DETACHABLE UPPER PORTION

Abstract: The invention refers to a conveyor chain forming part of a chain conveyor and incorporates a number of cardanic interconnected links, each of which incorporates an interconnecting lower part (2, 3) and a load carrying upper part (1). The invention is characterized therein that the upper part (1) is equipped with connecting means (4, 5, 6, 8) for detachable fitting of further load carrying members (9), such as carriers, supports for rollers and protecting plates.

Description: The present invention relates to conveyor chains and more specifically to a link for a conveyor chain comprising a lower base part and a load carrying upper part and means for detachably mounting a load carrying member including laterally extending rail means projecting from said upper part. Chain conveyors are commonly known. They usually consist of a girder system incorporating a track, in which a conveyor chain, intended to carry goods to be transported, is driven in forward direction. The conveyor chain is endless and usually consists of a number of links interconnected by cardanic joints. The driving of the chain is effected by means of electric motors, which act upon the chain via different types of transmissions. The conveyor chains in recent chain conveyors can extend vertically, horizontally and at oblique angles and they can be curved in different directions. Two or more tracks are often arranged to cooperate and to seize the objects to be transported to lift them up to a higher level or to lower them to a lower level. The tracks at their upper side also may be equipped with free-running rollers, whereby goods, which for any reason is retarde, may roll freely in relation to the tracks. Examples of conveyor chains of known type are described in Swedish patent specifications 7906174-3 and 8105758-0. A frequently occuring problem at chain conveyors of the type described above is that they at various times must convey objects of different types. A conveyor chain with a certain carrying surface then may be improper for conveying goods of other kind that the goods earlier transported. In such a case it may be necessary completely to exchange the conveyor chain, which is of course an extensive operation which rather should be avoided. It therefore since long has been a desideratum to provide a conveyor chain, which can easily be converted thus that it in a satisfactory manner can transport different types of objects at various times. US-A-3952860 discloses a conveyor chain at which the load carrying member is provided with fingers which snap into axially extending grooves in the rail means. EP-A-0032479 discloses a conveyor chain generally of the type defined in the pre-characterizing portion of claim 1 and similar to the one shown in US-A-3952860 wherein a load carrying member in form of wire cross flight is snapped into tranversal grooves in the upper side of a member attached to the chain links. None of these prior art publications shows a means for detachably mounting a load carrying member which includes as specified in the characteriting portion of claim 1, abutment means at one end of the upper load carrying part (laterally expending rail means) engageable with the load carrying member and further includes at least one flexible locking element at the opposite end defining a releasable locking member likewise engageable with said load carrying member. The links of the conveyor chain according to the invention generally are made from plastic material and it is appropriate that the connecting means are made integral with the load carrying upper part. A particular embodiment of the invention hereinafter will be described with reference to the drawings, in which Fig. 1 shows a chain link according to the invention as seen from above, Fig. 2 shows the same chain link seen partly in vertical section, Fig. 3 shows the chain link according to Fig. 1 seen from the side, Fig. 4 shows a modification of the chain link shown in Fig. 1. Fig. 5 shows one of the additional, load carrying members seen from the side, and Fig. 6 shows in perspective a chain link according to the invention having an additional, laod carrying member fitted thereto. The chain link according to Fig. 1 consists of a load carrying upper part 1 in form of a plate. This is supported by a partly hidden lower part, which incorporates a link head 2 and two clevis portions 3 provided with through-holes. On the upper side of the plate 1 are provided two rails 4, which are cast integrally with the plate 1 and with the lower part 2 and 3. The additional, load carrying member is intended to be pushed in on the rails from the left hand side as seen in the drawing. At this introduction side a shoulder 5 is provided between the rails on a resilient arm 6, such as further shown in Fig. 2. At the right hand side of the plate 1 in Fig. 1 is shown a stop plate 7 preventing the additional load carrying member from being pushed off from the upper part 1. It is possible to exchange this stop 7 for a resilient shoulder similar to that at the opposite side of the plate 1, whereby it will be possible to push on the additional load carrying member from both sides. Fig. 2 shows the chain link according to Fig. 1 in a section through the upper part 1 and through the shoulder 5, which is provided on the resilient arm 6. At the right hand side in the figure is shown the stop 7 and below the plate 1 is shown the clevis portions 3. Fig. 3 shows the chain link according to Fig. 1 as seen from the side with the plate 1, the link head 2, one of the clevis portions 3, the rails 4 and the shoulder 5 on the resilient arm 6. As can be seen from this figure the shanks of the rails 4 are projecting outwards. According to the invention it is also possible to let them project inwards, whereby the additional load carrying member has a design corresponding to the inwardly projecting shanks. Fig. 4 shows a modification of the chain link according to Fig. 1. As can be seen from the figure the shoulder 5 on the resilient arm 6 has been excluded and the ends of the rails 4 have been made laterally resilient instead. They also have been equipped with hook members 8 intended to cooperate with the additional load carrying member and to lock this after it has been pushed in position. It also should be pointed out that the rails 4 can be made slightly different, thus that the additional load carrying portion can be introduced in one manner only. Fig. 5 shows an embodiment of an additional load carrying member as seen from the side. This consists of a rather hard carrier 9 having a mainly U-shaped profile and inwardly folded edges 10. This carrier part is adapted to be pushed inwards on the rails 4. At the upper side of the carrier 9 has been provided softer, elongated blades 11, preferably of rubber or plastic material. They may be extruded together with the carrier part, which may be of other material or they may be fitted in other appropriate ways, e.g. by glueing or by means of dovetail grooves. The blades in the present case are intended to cooperate with the blades of a corresponding conveyor track and softly to seize the objects to be conveyed. In addition to the blades 11 shown in Fig. 5 it is possible to fit other upper parts, e.g. felt or cloth, which in a very lenient manner can convey objects vulnerable to scratching and the like. In such a case it is appropriate that the carrying part 9 is made from aluminium or the like, upon which textiles can be glued easily. Otherwise the carrier plate 9 is usually made from plastic material. Fig. 6 finally shows a cardan link with an additional load carrying member according to Fig. 5 fitted thereto. As can be seen from this figure the additional load carrying member can swiftly and easily be pushed in on the cardan link and as easily be removed without the necessity of otherwise making anything to the chain. By the present invention it thus has been provided a conveyor chain, which is universal in the sense that it can be used for conveying quite different objects and during quite different conditions. To alter the conveyor from transport of a certain goods to another type of goods or to substitute additional load carrying members on the track is very simple. It thereby also has been achieved the advantage that the stock-keeping for conveyor tracks can be simpler. The conveyor chain itself can be standardized and it is required only one type of chain links, on which desired additional load carrying members can be fitted. The invention is not limited to the embodiments shown but can be varied within the scope of the claims.

Claims: 1. A link for a conveyor chain comprising a lower base part (2,3) and a load carrying upper part (1) and connecting means (5,6,7,8) for detachably mounting a load carrying member (9) including laterally extending rail means (4) projecting from said upper part (1), said rail means securing the load carrying member against movement transverse thereto characterized in that said mounting means further includes abutment means (7) at one end of said rail means (4) engageable with said load carrying member (9) and at least one flexible locking element (5,6) at the opposite end defining a releasable locking member likewise engagable with said load carrying member. 2. A conveyor chain according to claim 1, wherein the connecting means incorporate a resilient shoulder (5), which by snap-action is adapted to lock the fitted additional load carrying member (9). 3. A conveyor chain according to claim 1, wherein the connecting means incorporate rails (4), which are resilient laterally at the entrance end for the additional load carrying member (9) and equipped with shoulder (8), whereby they can lock the additional load carrying member (9) by snap-action. 4. A conveyor chain according to claim 1, wherein the connecting means (4,5,6,8) are made integral with the load carrying upper part (1).

Inventors: ABBESTAM, GOERAN, LACHONIUS, LEIF, Abbestam, Göran
Applicants: SKF SPECIALTY PRODUCTS AB
Application year: 1989
Main classification: B65G17
IPC codes: B65G17