NL2002344C2

NL2002344C2 - Conveyor chain module, conveyor chain, conveyor and conveyor system.

Info

Publication number: NL2002344C2
Application number: NL2002344A
Authority: NL
Inventors: Remco Ende; Daniele Coen
Original assignee: Rexnord Flattop Europe Bv
Priority date: 2008-12-18
Filing date: 2008-12-18
Publication date: 2010-06-21

Description

P86775NL00

Title: Conveyor chain module, conveyor chain, conveyor and conveyor system

The invention generally relates to the field of modular conveyor chains, and in particular to chain modules, chains, conveyors and conveying systems arranged for cooperation with a fingered transfer device.

Modular conveyor chains are commonly formed in an endless loop to 5 circulate between divert elements along a conveying track. Articles to be transported may be transferred to or from a conveying surface using a transfer device disposed at the level of the conveying surface of the conveying track near the divert element.

Due to chordal action arising from the modular nature of the chain, 10 a gap between the conveying surface and the transfer device may have a varying width, which may negatively influence the stable transfer of products.

In order to address this issue, it has been proposed to provide the transfer device with fingers, and the conveying face of the conveyor with continuous grooves that may accommodate the fingers when they reach into 15 the conveying face.

A common example for such a configuration is a so-called raised rib chain configuration in which fingers of a finger plate may be accommodated in the grooves between the ribs, such that the upper surface of the fingers reaching into the conveying surface may be flush with the top surface of the 20 ribs. In a raised-rib configuration, the grooves are formed between interspaced lamellae of a body having a lamellar structure. As an alternative, the body may e.g. also have a solid top portion in which grooves have been provided such that the top face of the body is provided with lands between the grooves.

In order to accommodate the finger, the height of the ribs is 25 relatively large, which is a disadvantage as it increases the height of the modules. Especially when travelling about the divert elements in a strongly 2 curved path, the chordal action may increase again, so that the reliable transfer of products is reduced again.

It is an object of the invention to alleviate such disadvantage. Thereto, the invention provides for a module for a conveyor chain, comprising a 5 body which on front and rear sides includes a number of hinge loops protruding forward and rearward respectively relative to a conveying direction, the hinge loops extending transversely to the conveying direction and being spaced apart with mutual interspaces transversely to the conveying direction, the hinge loops further having hinge holes, such that front and rear 10 sides of successive modules are couplable, upon interdigitation of the hinge loops, with the aid of a hinge pin extending transversely to the conveying direction through the hinge loops, so that top faces of the bodies of the coupled modules form a conveying surface, wherein the top face of the body at least at the location of a hinge loop is provided with a groove extending in conveying 15 direction for cooperation with a finger of a transfer device, wherein the groove comprises a bottom portion that substantially merges with the top face of the body at a midsection of the body located between the front and rear sides of the body.

By providing a module in which the groove comprises a bottom 20 portion that substantially merges with the top face of the body at a midsection, it is achieved that the height of the module may be made relatively low. In other words, the module may be provided with a groove that centrally may have a depth that is less than the height of a finger that is arranged for cooperation with that groove.

25 By spacing a highest point of the bottom of the groove from the top face of the body to a depth less than the width of the groove or even to a depth less than half the width of the groove, the stability of products to be conveyed on the conveying surface is increased. By providing a highest point of the bottom of the groove at the level of the top face of the body, stability may yet 30 be enhanced further. By providing a highest point of the bottom of the groove 3 flush with the top faced face of the body, a flat area for supporting the products may be obtained at a midsection of the body of the module.

The top face of the body may comprise a flat zone extending both in conveying direction and transversely to the conveying direction. In such a 5 configuration, the grooves may not extend continuously in the top face of the conveyor chain, but may be interrupted, e.g. by flat zones at the midsections of the body of successive modules in the conveyor chain.

By providing a lower most point of the bottom of the groove at an end portion of the hinge loop facing away from the midsection of the body, it is 10 achieved that the depth of the groove is greatest at the location of the extremity of the body, such that when a module turns around a divert element along a path that is curved relatively strongly, the extremity of the body portion of that module is configured to accommodate the height of a finger of a fingered transfer device.

15 The bottom of the groove may be curved in conveying direction, e.g.

about an axis extending transversely to the module. Such curvature allows smooth cooperation with a bottom portion of a finger having a corresponding curve. However, the bottom of the groove may alternatively e.g. may have a stepped or straight sloping configuration.

20 The groove may e.g. extend between the end portion of the hinge loop and the midsection of the body, and the bottom of the groove may e.g. be curved to slope downwardly in a direction away from the midsection of the body.

The top face of the body may at the location of the hinge loop be 25 provided with a plurality of grooves extending in conveying direction, the grooves being spaced apart with mutual interspaces transversely to the conveying direction. This may e.g. be the case if the width of the fingers of the transfer device transverse to the conveying direction is relatively small compared to the width of the hinge loops. As an alternative or in addition, the 30 top face of the body may at the interspaces between the hinge loops be 4 provided with one or more grooves extending in conveying direction, the groove being spaced apart with mutual interspaces transversely to the conveying direction. This way, a relatively large number of grooves may be accommodated in the top face of the body.

5 By providing a bottom face of the body that is concavely curved in conveying direction, the ability of the module to pass along a divert element in a strongly curved path is increased. Advantageously, the curvature of the bottom face of the body may substantially follow the curvature of the bottom of the groove.

10 The invention also relates to a conveyor chain, comprising a plurality of modules succeeding in a conveying direction, front and rear sides of successive modules being coupled with interdigitating hinge loops with the aid of a hinge pin extending transversely to the conveying direction, such that the top faces of the bodies of the coupled modules form a conveying service, 15 grooves of succeeding modules being aligned in conveying direction. In such configuration, the belt may have a single row of modules, that may also have a mat-like configuration in which a plurality of modules is placed side by side transfers to the conveying direction. In such a mat-like structure, the modules may be incorporated into the mat in a brick-like pattern.

20 Transverse to the conveying direction, a module may e.g. be provided with a single hinge loop at a font side, and two hinge loops at a rear side that are interspaced to receive a front hinge loop of a similar, succeeding module. In a mat-like configuration, the body may e.g. on front and rear side be provided with a plurality of hinge loops. Such hinge loops may be staggered 25 relative to each other. Hinge loops and their interspacing may e.g. vary across the width of a module. For example, an end module located near the edge of the mat may be provided with a protrusion that is relatively large transverse to the conveying direction to accommodate a locking member for transversely locking a hinge pin.

δ

The body of the module may e.g. comprise a central portion from which the hinge loops protrude. As an alternative, the body may e.g. extend in a zig-zag or undulating configuration transversely to the conveying direction. Also, the body of the module may e.g. be build up by a plurality of lamellae 5 that are spacedly connected transversely to the conveying direction.

The invention further relates to a conveyor, comprising a conveyor chain formed in an endless loop and circulating along a conveying track, the conveyor chain being guided to turnabout a nose over bar extending transversely to the conveying track. Such a nose over bar is a divert element 10 with a guide face that has a relatively strong curvature, e.g. a circular radius of curvature of several centimetres. The curvature of the nose over bar may e.g. correspond with the curvature of the bottom of the grooves in the modules of the modulate conveyor chain.

The invention further relates to a conveying system, comprising a 15 conveyor and a fingered transfer device disposed at the level of the conveyor face on the conveying track, of which transfer device one or more fingers reach into grooves in top faces of the modules of conveyor at a location of the nose over bar. Advantageously, such a conveying system may comprise a second conveyor positioned end to end with the first conveyor, the fingered transfer 20 device being interposed in an interspace between the conveyors, while fingers of the fingered transfer device extend in opposite directions and reach into grooves in top faces of modules of both conveyors at the location of the nose over bars.

The invention shall be illustrated further using exemplary 25 embodiments that arc shown in drawings. In the drawings,

Fig. 1 is a perspective top view of a conveyor chain module;

Fig. 2 is perspective top view of a conveying system including two conveyor belts built up with modules according to fig. 1;

Fig. 3 is a side view of the conveying system of fig. 1; 6

Fig. 4 is a prospective top view of a detail of fig. 2 showing a fingered transfer device cooperating with a modular conveyor belt, and

Fig. 5 is a perspective top view of an alternative embodiment of a conveyor chain module; 5 Fig. 6 is a schematic cross sectional side view of the module of fig. 1, and

Fig. 7 shows an alternative embodiment of the module of fig. 6.

The figures only show schematic representations of exemplary embodiments of the invention, and are shown as non-limiting examples only.

10 In the figures, similar or corresponding parts have been provided with the same reference numerals.

Figure 1 shows a module 1 for a conveyor chain 10. The module 1 comprises a body 2. The body 2 includes on the front side 3 and the rear side 4 a number of hinge loops δ. The hinge loops 5 protrude forward and rearward 15 respectively relative to a conveying direction that is indicated with arrow P. The hinge loops 5 extend transversely to the conveying direction P and are spaced apart with mutual interspaces 6 transversely to the conveying direction P. The hinge loops 5 are provided with hinge holes 7. Referring to Figure 2 it is shown that the front side 3 and rear side 4 of succeeding modules 20 in transport direction P are couplable, under interdigitation of the hinge loops 5 with the aid of a hinge pin 21 extending transversely to the conveying direction P through the hinge loops 5. This way, a conveyor chain 10 may be formed in which top faces 8 of the bodies 2 of the coupled modules 1 form a conveying surface 9.

25 The top face 8 of the body 2 is at the location of each hinge loop 5 provided with a plurality of grooves 11 extending in conveying direction P for cooperation with respective fingers 12 of a transfer device 13. The grooves 11 comprise a bottom portion 14 that substantially merges with the top face 8 of the body 2 at a midsection 17 of the body 2 located between the front side 3 30 and the rear side 4 of the body. Within the context of this application, the term 7 “substantially merges” is meant to express that the bottom portion 14 of the groove 11 may be at or slightly below the top face 8 of the body 2, In the example shown, a highest point of the bottom portion 14 of a groove 11 is at the level of the top face 8 of the body 2. This may be seen best in Fig, 6. Within 5 the definition of a bottom portion 14 that substantially merges with the top face 8 of the body 2, the bottom portion 14 of the groove 11 may be spaced from the top face 8 of the body 2 to a depth D less than the width W of the groove. Preferably, a highest point of the bottom portion 14 of the groove 11 is spaced from the top face 8 of the body 2 to a depth D of half the width W of the groove 10 11 or less. Such an embodiment is shown in Fig. 7.

As shown in Figures 1 and 2, the bottom 15 of the groove 11 is curved in conveying direction P, i.e. curved about an axis of curvature extending transversely to the conveying direction P. A lower point of the bottom 15 of the groove 11 is at an end portion 16 of the hinge loop 5 facing 15 away from the midsection 17 of the body 2. As shown, the groove 11 extends between the end portion 16 of the hinge loop 5 and the midsection 17 of the body 2. The bottom 15 of the groove 11 is curved to slope downwardly in a direction away from the midsection 17 of the body 2.

Although not shown in this embodiment, at the midsection 17 of the 20 body 2, the top face 8 of the body 2 may comprise a flat zone that extends both in conveying direction P and transversely to the conveying direction. In the embodiment shown, this fat zone 18 extends in conveying direction P only for a short distance. In other embodiments, this distance may be larger.

In the embodiment shown, the top face 8 of the body 2 is, at the 25 location of each hinge loop 5, provided with a plurality of grooves 11 extending in conveying direction P. The grooves are spaced apart with mutual interspaces 19 transversely to the conveying direction P. In addition, the top face 8 of the body 2 is at the interspaces 6 between the hinge loops 5 provided with a plurality of grooves 11 that extend in conveying direction P. These 30 grooves 11 are also spaced apart with mutual interspaces 19 transversely to 8 the conveying direction. As may be seen for example in Fig. 3, a bottom face 20 of the body 2 is concavely curved in conveying direction P. As shown, the curvature of the bottom face 20 of the body 2 substantially follows the curvature of the bottom 15 of the groove 11.

5 In Fig. 4, an alternative embodiment of a module 1 is shown, in which the body 2 extends in a zigzag configuration

Referring to Figs. 2 and 3, it is shown that a conveyor chain 10 may comprise a plurality of modules 1 succeeding in conveying direction P. The front sides 3 and the rear sides 4 of successive modules 2 are coupled with 10 interdigitating hinge loops 5 with the aid of a hinge pin 21 that extends transversely to conveying direction P. Top faces 8 of the bodies 2 of the coupled modules 1 form a conveying surface 9, and grooves 11 of succeeding modules 1 are aligned in conveying direction P. Figures 2 and 3 also show two conveyors 22. Each conveyor 22 comprises a conveyor chain 10 that is formed 15 in an endless loop, and that circulates along a conveying track 23. The conveyor chain 10 is guided to turn about a nose over bar 24 that extends transversely to the conveying track 23. For the left conveyor, also a sprocket wheel 50 is shown that drives the conveyor chain 10. As shown, the curvature of the nose over bar 24 corresponds with the curvature of the bottoms 15 of the 20 grooves 11 in the modules 1 of the modular conveyor chain 10.

Referring to Figures 3 and 4, a conveying system 25 is shown, comprising a first conveyor 22 and a second conveyor 22 that are positioned end-to-end, and a fingered transfer device 13 disposed at the level of the conveying surface 9 on the conveying track 23. A plurality of fingers 12 reach 25 into corresponding grooves 11 in top faces 8 of modules 1 of the conveyor 10 at the location of the nose over bar 24. In particular, the fingered transfer device 13 is interposed in an interspace 26 between the conveyors 22, while fingers 12 of the transfer device 13 extend in opposite directions and reach into grooves 11 in top faces 8 of modules 1 of both conveyors 22 at the location of the nose 30 over bars 24. Back portions 29 of the fingers 12 are flush with the top faces 8, 9 so that products may be transferred stably from the convejdng surface 9 to the transfer device 13, This may be seen best in Fig. 4 As shown, the fingered transfer device 13 is embodied as a double fingerplate.

Referring to Figures 2 and 3, it is shown that articles 27 may be 5 transferred smoothly from a conveyor chain 10 of a first conveyor 22 via the fingered transfer device 13 to a conveyor chain 10 of a second conveyor 22. Due to the nose over bars 24, the conveyors 22 may be placed end-to-end with only a very small interspace 26. The fingers 12 of the fingered transfer device 13 may be relatively short, and may, when a module 1 is still on the conveying 10 track and about to follow the curved path, reach into the top face 8 of the body 2 for only about less than 1/3 of the length of the module 1 in conveying direction. As shown, the fingers 12 may reach into the groove 11 only up to a position above the hinge holes 7 when the module 1 is still in a horizontal position and about to start its curved path. Due to the fact that a bottom 15 portion 14 of the bottom 15 of groove 11 is at the midsection 17 of the body 2 at or close to the top face 8 of the body 2, the groove 11 may be curved strongly relative to the height of the module. In conveying direction, the grooves 11 do not extend continuously along the conveyor chain 10, but are interrupted at the locations where they reach the top faces 8 of the bodies 2. At the 20 midsections 17 of the bodies 2, the depth D of the grooves is insufficient to accommodate the height of the fingers 12 to an extent that back portions 29 of the fingers 12 are flush with the top faces 8.

Due to the small interspace, the top surface 31 of the fingered transfer device 13 has only a limited length in conveying direction P, such that 25 it docs not form a dead zone in which products may accumulate.

It shall be clear to the skilled person that the invention is not limited to the exemplary embodiments described, and that many variations are possible within the framework of the invention as defined in the appended claims.

Claims

1. Module voor een transportketting, omvattende een lijf dat aan voor- en achterzijden een aantal scharnierogen omvat die respectievelijk voorwaarts en achterwaarts reiken ten opzichte van een transportrichting, welke scharnierogen zich dwars op de transportrichting uitstrekken en met 5 onderlinge tussenruimten dwars op de transportrichting uiteen zijn geplaatst, welke scharnierogen voorts scharniergaten hebben, zodanig dat voor- en achterzijden van opeenvolgende modules, onder samenwerking van de scharnierogen, koppelbaar zijn met behulp van een zich dwars op de transportrichting door de scharnierogen heen uitstrekkende scharnierpen, 10 zodanig dat bovenvlakken van de lijfdelen van de gekoppelde modules een transportvlak vormen, waarbij het bovenvlak van het lijfdeel tenminste ter plaatse van een scharnieroog is voorzien van een zich in transportrichting uitstrekkende groef voor samenwerking met een vinger van een overschuifinrichting, en waarbij de groef een bodemdeel omvat dat in 15 hoofdzaak gelijk ligt met het bovenvlak van het lijfdeel ter plaatse van een middengedeelte van het lijfdeel dat tussen de voor- en achterzijde van het lijfdeel is gelegen.CLAIMS 1. Module for a conveyor chain, comprising a body which comprises a number of hinge eyes on front and rear sides which respectively extend forwards and backwards with respect to a conveying direction, which hinge eyes extend transversely of the conveying direction and are spaced apart transversely to the conveying direction are placed, which hinge eyes further have hinge holes, such that front and rear sides of successive modules can be coupled, under cooperation of the hinge eyes, by means of a hinge pin extending transversely to the direction of transport through the hinge eyes, such that upper surfaces of the body parts of the coupled modules form a conveying surface, the upper surface of the body part being provided, at least at the location of a hinge eye, with a groove extending in conveying direction for cooperation with a finger of a slide-over device, and wherein the groove comprises a bottom part which in Is substantially flush with the upper surface of the body part at the location of a middle part of the body part which is situated between the front and rear side of the body part.

2. De module volgens conclusie 1, waarbij het hoogste punt van de bodem van de groef verwijderd is van het bovenvlak van het lijfdeel met een diepte die 20 kleiner is dan de breedte van de groef.2. The module according to claim 1, wherein the highest point of the bottom of the groove is removed from the upper surface of the body part with a depth that is smaller than the width of the groove.

3. De module volgens conclusie 1, waarbij het hoogste punt van de bodem van de groef verwijderd is van het bovenvlak van het lijfdeel met een diepte die minder is dan de helft de breedte van de groef.The module of claim 1, wherein the highest point of the bottom of the groove is removed from the upper surface of the body portion with a depth that is less than half the width of the groove.

4. De module volgens conclusie 1, waarbij een hoogste punt van de bodem 25 van de groef op het niveau van het bovenvlak van het lijfdeel is gelegen.The module according to claim 1, wherein a highest point of the bottom 25 of the groove is located at the level of the upper surface of the body part.

5. De module volgens één der voorgaande conclusies, waarbij de bodem van de groef in transportrichting gekromd is.The module according to any of the preceding claims, wherein the bottom of the groove is curved in the transport direction.

6. De module volgens één der voorgaande conclusies, waarbij een laagste punt van de bodem van de groef gelegen is bij een einddeel van het scharnieroog dat van het middendeel van het lijfdeel af is gewend.The module according to any one of the preceding claims, wherein a lowest point of the bottom of the groove is located at an end part of the hinge eye that is remote from the middle part of the body part.

7. De module volgens conclusie 5 of 6, waarbij de groef zich uitstrekt tussen 5 het einddeel van het scharnieroog en het middendeel van het lijfdeel.7. The module according to claim 5 or 6, wherein the groove extends between the end part of the hinge eye and the middle part of the body part.

8. De module volgens één der voorgaande conclusies, waarbij de bodem van de groef is gekromd om neerwaarts af te lopen in een richting die af is gekeerd van een middendeel van het lijfdeel dat tussen de voor- en achterzijden in is gelegen.The module of any one of the preceding claims, wherein the bottom of the groove is curved to run downwardly in a direction away from a middle portion of the body portion located between the front and rear sides.

9. De module volgens één der conclusies 4-8, waarbij het bovenvlak van het lijfdeel ter plaatse van een middendeel van een lijfdeel dat tussen de voor- en achterzij de is gelegen, een vlak gebied omvat dat zich zowel in transportrichting als dwars daarop uitstrekt.The module according to any of claims 4-8, wherein the upper surface of the body part at the location of a middle part of a body part located between the front and rear side comprises a flat area extending both in transport direction and transversely thereto .

10. De module volgens één der voorgaande conclusies, waarbij het bovenvlak 15 van het lijfdeel ter plaatste van een scharnieroog is voorzien van een veelvoud aan zich in transportrichting uitstrekkende groeven, welke groeven dwars op de transportrichting met onderlinge tussenruimten uiteen zijn geplaatst.The module according to any one of the preceding claims, wherein the top surface 15 of the body part is provided with a hinge eye at its location with a plurality of grooves extending in the conveying direction, which grooves are spaced apart transversely to the conveying direction with mutual gaps.

11. De module volgens één der voorgaande conclusies, waarbij het bovenvlak van het lijfdeel ter plaatse van de tussenruimten tussen de scharnierogen is 20 voorzien van één of meer zich in transportrichting uitstrekkende groeven, waarbij de groeven dwars op de transportrichting met onderlinge tussenruimten uiteen zijn geplaatst.11. The module according to any one of the preceding claims, wherein the upper surface of the body part is provided at the area of the spaces between the hinge eyes with one or more grooves extending in the conveying direction, the grooves being spaced apart transversely to the conveying direction with mutual spaces .

12. De module volgens één der voorgaande conclusies, waarbij een bodemvlak van het lijfdeel in transportrichting concaaf is gekromd.The module according to any one of the preceding claims, wherein a bottom surface of the body part is concave in the conveying direction.

13. De module van conclusie 12, waarbij de kromming van het ondervlak van het lijfdeel in hoofdzaak de kromming van de bodem van de groef volgt.The module of claim 12, wherein the curvature of the bottom surface of the body portion substantially follows the curvature of the bottom of the groove.

14. Een transportketting omvattende een veelvoud aan modules volgens één der voorgaande conclusies die elkaar in een transportrichting opvolgen, waarbij voor- en achterzijden van opeenvolgende modules onder samenwerking van de 30 scharnierogen met behulp van een zich dwars op de transportrichting uitstrekkende scharnierpen zijn gekoppeld, zodanig dat bovenvlakken van de lijfdelen van de gekoppelde modules een transportvlak vormen, en groeven van opeenvolgende modules in transportrichting opgelijnd zijn.14. A conveyor chain comprising a plurality of modules according to any one of the preceding claims which follow one another in a conveying direction, wherein front and rear sides of successive modules are coupled under cooperation of the hinge eyes with the aid of a hinge pin extending transversely to the conveying direction, such that upper surfaces of the body parts of the coupled modules form a conveying surface, and grooves of successive modules are aligned in the conveying direction.

15. Een transporteur, omvattende een transportketting volgens conclusie 14, 5 gevormd in een eindloze lus en circulerend langs een transportbaan, waarbij de transportketting wordt geleid om een bocht te maken om een zich dwars op de transportbaan uitstrekkende omleidbalk.A conveyor, comprising a conveyor chain according to claim 14, formed in an endless loop and circulating along a conveyor track, wherein the conveyor chain is guided to make a bend about a guide bar extending transversely to the conveyor track.

16. De transporteur volgens conclusie 15, waarbij de kromming van de omleidbalk correspondeert met de kromming van de bodem van de groeven in 10 de modules van de modulaire transportketting.16. The conveyor according to claim 15, wherein the curvature of the deflecting beam corresponds to the curvature of the bottom of the grooves in the modules of the modular conveyor chain.

17. Een transportsysteem, omvattende een transporteur volgens conclusie 15 of 16 en een van vingers voorziene overschuifinrichting die ter plaatse van het transportvlak op de transportbaan is opgesteld, van welke overschuifinrichting één of meer vingers ter plaatse van de omleidbalk in 15 groeven reiken die in bovenvlakken van modules van de transporteur zijn aangebracht.17. A transport system, comprising a conveyor according to claim 15 or 16 and a finger-operated transfer device which is arranged on the transport track at the location of the transport surface, of which transfer device one or more fingers reach at the location of the deflection beam in grooves extending in upper surfaces. of modules of the conveyor.

18. Een transportsysteem volgens conclusie 17, omvattende een tweede transporteur volgens conclusie 15 of 16 die kops met de eerste transporteur is opgesteld, en waarbij de van vingers voorziene overschuifinrichting ingeplaatst 20 is in een tussenruimte tussen de transporteurs, terwijl de van vingers voorziene overschuifinrichting zich in tegenovergestelde richtingen uitstrekt en ter plaatse van de omleidbalk reikt in groeven die in bovenvlakken van de modules van beide transporteurs zijn aangebracht.18. A conveyor system as claimed in claim 17, comprising a second conveyor as claimed in claim 15 or 16, which is arranged end-to-end with the first conveyor, and wherein the finger-provided sliding device is placed in an intermediate space between the conveyors, while the finger-provided sliding device is located extends in opposite directions and extends at the location of the deflection beam in grooves arranged in upper surfaces of the modules of both conveyors.

19. Een transportsysteem volgens conclusies 17 of 18, waarin de van vingers 25 voorziene overschuifinrichting een vingerplaat omvat.19. A transport system according to claim 17 or 18, wherein the sliding device provided with fingers 25 comprises a finger plate.