GB2076769A

GB2076769A - Conveying Assembly

Info

Publication number: GB2076769A
Application number: GB8106023A
Authority: GB
Original assignee: NAT RES DEV; National Research Development Corp of India
Current assignee: NAT RES DEV; National Research Development Corp of India
Priority date: 1980-06-03
Filing date: 1981-02-26
Publication date: 1981-12-09
Also published as: GB2076769B

Abstract

A conveying assembly e.g. for use in a transplanter, in which inclined or roughly vertical belts are used to convey individual block-embracing portions detached from a bandolier of such blocks to a planting location where they are released. Where roughly vertical conveyor belts 133 are used, these are designed to embrace the blocks making additional support unnecessary. Where inclined belts 204, 205 are used (Figures 6 and 8), a support belt 202 or equivalent item is provided between two side belts which grip the blocks and prevent them sliding or tumbling down the support. In both cases, the belts are preferably arranged to compensate for the forward motion of the transplanter so as to encourage the released blocks to fall vertically, <IMAGE>

Description

SPECIFICATION Conveying Assembly The present invention relates to a conveying assembly and in particular, but not exclusively, to a conveying assembly for use in an apparatus for handling growing blocks, in particular plantbearing growing blocks interconnected as a bandolier of such blocks.

The term "bandolier" in this context, and as used hereinafter throughout the specification, is to be interpreted as meaning a string of growing blocks linked together by a joining medium with each block having, when arranged for normal use, an upper face for growing a plant and a lower face for the block to stand on.

According to the present invention, a conveying assembly comprises an array of belts at least two of which are conveyor belts adapted to grip opposite sides of the object to be conveyed so as to discourage relative movement between the object and the belts.

In first embodiments of the invention, the gripper belts will provide a sufficient grip on the object wholly to support the object. Thus, additional support means are not required.

In one such embodiment, for example, the assembly comprises a pair of laterally-spaced flat conveyor belts each reinforced by a respective pair of laterally-spaced compact-section belts running the length of the flat conveyor belts. The term "flat" in this context is to be taken as meaning only that the width of the belt to which the term refers is much greater than the thickness of the belt. It should not for example be taken to imply that the surface of the belt concerned is necessarily smooth.In contrast, the term "compact" is to be taken as meaning that the cross-sectional dimensions of the belt to which the term refers are either roughtly the same in all directions, (i.e. when the belt has a nominally circuiar cross-section) or that these dimensions do not differ greatly (e.g. as will be the case with a nominally square-section or with a reactangularsection or triangular-section belt for example in which the maximum cross-sectional dimension of the belt is not more than, say, two or three times the minimum cross-sectional dimension).

Conveniently, the compact-section belts above referred to are woven in and out of successive apertures in the border regions of the associated flat belts.

Conveniently, the belts pass around a pair of waisted and grooved rollers at one end of the assembly and around a pair of parallel-sided grooved rollers at the other end of the assembly.

in second embodiments of the invention, the conveyor belts adapted to grip opposite sides of the object to be conveyed provide insufficient grip on the object wholly to support the object and in these embodiments, therefore, an additional support means has to be provided.

In one such embodiment, the conveyor belts above referred to comprise two side belts arranged to grip opposite sides of the object and the support means provides a support surface underneath the object when so grippped.

Conveniently, the support means comprises a further conveyor belt or conveyor rollers or conveyor wheels or a chute or any suitable combination of any two or more of these items.

Conveniently, the two side belts above referred to pass around a pair of splayed discharge wheels arranged at the bottom of the assembly to grip and support the object to be conveyed when it reaches the discharge end of the assembly and to release the object only when it is clear of the support means.

Preferably in this latter case, the splay of the discharge wheels is such that the object to be conveyed is released by the wheels at or near the lowest point of travel of the object between the wheels.

Where the object to be conveyed is deformable to a preselected dimension, then the conveying assemblies above referred to in respect of the second embodiment of the invention conveniently include, upstream of the conveying belts, a sizing device arranged to press the object to be conveyed to a preselected transverse width dimension which is sufficiently in excess of the lateral spacing of the side belts to encourage the desired gripping action by these belts. The term "transverse width dimension" is to be taken as meaning in this context the width dimension of the object measured transversely to the direction of motion of the object when it is being urged along by the conveying belts.

Conveniently the sizing device may comprise or form part of a feed device for feeding the object into the input end of the conveying assembly.

The invention also includes an apparatus for handling a bandolier as hereinbefore defined when incorporating a conveying assembly according to the present invention.

In particular, but not exclusively, the invention includes an apparatus for handling a bandolier as hereinbefore defined comprising detachment means for detaching an end block-embracing portion of the bandolier and a conveying assembly according to the present invention for feeding the detached end block-embracing portion of the bandolier towards a planting location for the block.

Conveniently, the apparatus also includes feed means for feeding the bandolier to the detachment means so that each successive operation of the detachment means detaches a single end block-embracing portion from the remainder of the bandolier, in which case the feed means conveniently constitutes the feed device referred to earlier.

Conveniently, when the conveying assembly in the apparatus is according to the first embodiment of the invention, then the conveying belts of the assembly are arranged to move substantially vertically downwards relative to the chassis of the apparatus, though preferably with a component of horizontal motion to compensate for movement of the apparatus over the ground and encourage the discharged blocks to enter the ground vertically.

When the conveying assembly in the apparatus is according to the second embodiment of the invention, then once again the assembly preferably operates to give the detached portions of the bandolier a component of horizontal motion to compensate for movement of the apparatus over the ground and encourage the blocks to enter the ground vertically.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a general perspective view of a bandolier-handling apparatus according to the present invention showing a guillotine and two feed arms for feeding the bandolier towards the guillotine; Figure 2A is an underneath plan view of a catch mechanism designed to ensure that the bandolier is stationary when the guillotine operates; Figure 2B is a perspective view showing the mechanical drive to the feed arms; Figure 3 is a side perspective view of a transplanter incorporating the bandolier-handling apparatus and shows a vertical-belt conveying assembly in accordance with the present invention; Figure 4 is a scrap view of one of the conveyor belts in the assembly of Figure 3 and of the pulleys around which it passes;; Figure 5 shows the drive lay-out for the transplanter; Figure 6 is a side view of a conveying assembly according to the second embodiment of the invention, this Figure also showing the transplanter share with which the assembly will co-operate in practice; Figure 7 is a side view, on an enlarged scale, of the discharge end of the second assembly showing more clearly its co-operation with the transplanter share; Figure 8 is a plan view of the second assembly; and Figure 9 is an end view, also on an enlarged scale, of the discharge end of the second assembly and the transplanter share.

Referring first to Figure 1, the transplanter 10 comprises a machine 12 for transplanting plantbearing growing blocks 14 in the ground and a block-handling apparatus 16 for presenting the machine with individual-vertically-orientated growing blocks from a bandolier 18 charged with such blocks. For clarity and convenience, the plants have been omitted from the illustration.

Apparatus 1 6 has two functions. First periodically to grip the bandolier 18 and to move it one pitch forward, and secondly to sever successive and block-embracing portions off the bandolier for delivery to machine 12.

The principal components of the transport mechanism in apparatus 1 6 include gripper bars 30, clamp 32, 33 and a powered, continuouslyrotating foam-rubber guide roller 29 which is driven in an anti-clockwise sense (as viewed in Figure 1) but with a peripheral velocity in excess of that imparted to the bandolier by the feed means during its intermittant travel towards the detachment means.

The gripper bars 30 of the block-handling apparatus 1 6 are spaced apart by the pitch of the bandolier blocks 14 so as to be able to engage the bandolier on opposite sides of spacer portions 48.

The gripper bars 30 are in the form of freelyrotating roller members carried by brackets 49 on first parts 50 of two internally-sprung telescopic support members 52, 53. The second (support) parts 55 of these members are pivotally mounted at one end on a reciprocating drive member 37 for swinging motion about stub axles 57 between pivotally open positions and pivotally closed positions. In a modification (not shown), the axles 57 are replaced by a single centrally-located axle on which both the support members are mounted by appropriate lug portions of those members.

At what may be termed their "inner" ends, support parts 50 carry the clamp components 32, 33. The two blades 110, 111 of the guillotinetype detachment means, however, which are designed to shear through the bandolier to cut off the end block-engaging portion, are carried on support parts 55 adjacent clamp 32, 33 and resilient sponge rubber pads 11 3, 114 are carried just behind the blades to hold the block-engaging portion of the bandolier in place during and immediately following detachment.

At roughly their mid-lengths, the second (female) parts 55 of support members 52, 53 carry pivoted collars 61 which provide pivotal connections between these members and a toggle mechanism 62.

The two elements of the toggle mechanism 62 are connected together by a hinge-pin 66 which projects through a slot 68 (Figure 2A) in the drive member for engagement in an appropriate retaining notch 70 in one arm 71 of a bell crank lever 72. A tension spring 74 connected between drive member 37 and, by a collar 75, also with hinge-pin 66, urges pin 66 along slot 68 away from support parts 55. For clarity, collar 75 is only indicated in broken line in Figure 2A.

The free end of the other arm (78) of lever 72 is urged in the opposite direction by a second tension spring 80 connected between drive member 37 and the mid point of that arm. Thus the effect of this second spring is to maintain notch 70 in engagement with hinge-pin 66 so as to keep the toggle at its extended setting in which it will hold the support arms 52, 53 in their open positions.

A stop 82 is provided which on engagement of the projecting portion of arm 78 will urge the lever 72 in a clockwise direction (as viewed in Figure 2A) to disengage notch 70 from hinge-pin 66 so that the pin can travel down to the opposite end of slot 68 under the influence of spring 74 as hereinbefore described.

The relatching mechanism is provided by a link 116 (Figure 2B) which extends from hinge-pin 66 to a roller 118 engaging one edge of a drive arm 120.

The drive arm is mounted on a support bracket 122 welded to drive member 37 for restricted pivotal movement about a vertical stub axle 123.

To one side of axle 123, the drive arm-120 is urged by tension spring 125 into engagement with an upstanding lug 127 also welded to drive member 37. On the other side of axle 123, the drive arm is connected to a resiprocating crank 129.

The arrangement is completed by a damper 64 preventing support members 52, 53 from approaching one another at too fast a rate and by a stop 131 secured to a base plate 92 which is bolted to the machine 12 and which supports, one way or another, the various constituent parts of the block-handling apparatus 1 6. This plate is apertured at 94 with the side edges of the aperture supporting four rollers 96 on which the drive member 37 is mounted.

It is important, when considering the operation of the apparatus and the assembly of which it forms a part, to remember that stops 40, stop 82, cams 42 and abutment 131 are rigidly secured to this base plate whereas the support members 52, 53, the drive member 37 and the various items supported on these members are able to move freely, subject of course to any restriction imposed on this movement by the stops 40 etc.

It is also important to note that the operative faces of the cams 42 are of a shallow vee formation with the apex of the vees positioned to be engaged by the cam-engaging elements 41 when the support members move into their fully closed positions. It should further be noted that the stop-engaging faces of arms 39 should be curved as shown so that any swinging movement of these arms towards to away from the bandolier feed path while in engagement with the stops 40 should not result in a corresponding longitudinal movement of the support members 52, 53 parallel to the feed path.

The operation of apparatus 1 6 will now be described from the beginning of its operational cycle, at which the support members 52, 53 are held in their open position by the extended toggle mechanism 62 and the drive member 37 is still moving towards the right (as viewed in Figure 1) and approaching the end of its stroke. At this situation, the projecting end 78 of cam lever 72 has just engaged with stop member 82 and as a result, further movement of the drive member to complete its stroke drives lever 72 clockwise (as viewed in Figure 2A) to release notch 70 from hinge-pin 66.This allows tension spring 74 to pull hinge-pin 66 to the other end of slot 68 so as to collapse the toggle 62, and, in so doing, to move the support members 52, 53 to the partially closed position in which the leading gripper bars 30 are positioned at the joining portion of the bandolier just behing the foremost block 14.

Having the latter gripper bars only partially operative at this stage enables longitudinal adjustment of the bandolier to take place in the event of any misalignment with gripper bars 30.

The reciprocating drive member 37 now begins its return stroke pulling the bandolier along with it and, in due course, the elements 41 engage the converging front faces of cams 42 and ride along these surfaces until they reach the cam apices. At this point the support members 52, 53, gripper bars 30 holding clamp 32, 33 and blades 110, 111 are all fully operative.

Further movement of the drive means along this stroke brings arms 39 into engagement with stops 40 thereby to prevent further longitudinal movement of supoprt parts 50. The result is that the gripper bars 30, and more importantly the holding clamp 32, 33, lock the associated regions of the bandolier against further forward movement while the other parts 55 of the support members continue to move with the drive member 37 to tear off the end block-embracing portion from the bandolier if, for any reason, the blades 11 0, 111 have failed to cut off this portion cleanly.

The detached block will now be held in place by pads 11 3, 114 as the continued movement of the crank 129 moves the leading edge of support member 37 into engagement with the stop 1 31.

With the support member 37 engaging stop 131 as above described, the feed means will begin its dwell period during which further motion of the crank 129 in the same direction as before will rotate drive arm 120 about axle 1 23 (against the action of spring 125) to open the toggle and release the detached block-engaging portion of the bandolier. This latter drops a small distance through aperture 94 to a pair of belt conveyors 1 33, 1 33 which transport the detached bandolier portion substantially vertically downwards for discharge into a furrow preformed by a conventional share 136 during the forward motion of the apparatus.Releasing the blocks during the dwell period of the feed means ensures that the detached blocks maintain their original vertical orientation as they drop to the belt conveyors 133, 133 and the latter maintain this orientation until discharge.

The continued rotation of the crank wheel will now reverse the direction of crank motion commencing the return stroke of the feed means once drive member 120 has moved back into contact with lug 127. During this stroke, elements 41 move round the outside of cams 42 to return the apparatus to the setting where the holding clamp 32, 33 and blades 110, 111 are ready to close behind the new end block of the bandolier to repeat the process above described.

It will of course be appreciated that the maximum separation of arms 39 from stops 40 must be equal to the pitch of the bandolier blocks if in each cycle of operations only a single end block-embracing portion is to be detached from the rest of the bandolier. This is because in each cycle of operations, it is the value of this maximum separation that determines the foward travel of the bandolier.

The construction of the belt conveyors 1 33 is best seen from Figure 4 which shows them to comprise a flat rubber-based belt 136 reinforced by a pair of plastics round-section belts 138, 139 woven in and out of successive apertures in the belt 1 36 as shown in the drawing. At their upper ends, the conveyors pass around a pair of waisted and flanged rollers 141 and at their lower ends around a pair of parallel-sided rollers 142 also illustrated in the Figure. Both sets of rollers are provided with peripheral grooves 143 to accommodate the presence of the round belts 138, 139 in the conveyors. The waisted form of drive rollers 141 was chosen so as to encourage the flat belt parts of the conveyor to "embrace" the blocks.For the same reason, the flat belts had to be highly flexible which meant that some form of keying had to be provided to prevent them from crumpling up on the drive rollers. In the belt design of Figure 4, this keying is provided by belts 1 38, 1 39. Localised distortions resulting from the way in which these belts are woven in and out of the border apertures in the flat belt components, ensures that the fall of any block slipping within the embrace of the flat belts will be limited to a few millimetres. This means that the original spacing of the blocks will be substantially preserved and the liklihood of plant damage by slipping blocks minimised.

Rollers 141 appear again in Figure 5 from which it will be seen that they are driven through bevel gear boxes 143 from a chain and sprocket connection 144 to a lay shaft 146. Reference numeral 147 indicate the hydraulic motor from which this shaft is driven. This motor may be powered, for example, from the external supply of the tractor used for towing the transplanter.

A flow-control valve is conveniently included in the hydraulic circuitry to the motor to allow the motor speed to be varied at will.

The lay shaft 146 is also used to drive the crank 129 referred to earlier while the guide roller 29 is driven through a bevel gearbox 149 by a chain and sprocket connection 1 50 to the input shaft for one of the two gear boxes 143.

Referring now to Figures 6 to 9, a conveying assembly 200 according to the second embodiment of the invention comprises a flat downwardly-inclined support belt 202 for supporting the individual bandolier-mounted blocks to be conveyed by the assembly and two round-section side belts 204, 205 arranged to grip the blocks and prevent them sliding or tumbling down the support belt. Reference numeral 136 indicates a furrow-forming share for the blocks.

The desired spacing of the side belts is set by two nip pulleys 207,208 at the upper end of the assembly and is maintained by 3 pairs of guides 209, 209' spaced apart along the length of the assembly. As also shown in the drawings, a pair of small vertical guide pulleys is provided between the nip pullies 207, 208 and the driving drum 213 referred to below. At the bottom end of the assembly a pair of splayed discharge wheels 210, 211 increases the separation of the side belts from the initial value set by nip pulleys 207, 208 to a greater value at which the belts are returned to an appropriately powered driving drum 213 at the upper end of the assembly.This same drum is used to drive the support belt 202 which at its lower end passes around an idling roll 21 5 so positioned relative to discharge wheels 210, 211 that these latter will accept blocks from the support belt and carry them clear of the support belt before releasing them to ground.

The position at which release will occur will depend of course on the splay angle and relative dimensions of the discharge wheels, these being chosen so that the block will be released at their lowest point of travel between the two wheels.

Because the wheels will only grip the upper regions of the now otherwise unsupported block in their travel from the support belt 202 to their release positions, the blocks are able to swing, under gravity, to a substantially vertical orientation, before they are released as above described.

Ideally, the horizontal component of motion imparted to the blocks by the discharge wheels at the moment of release will be substantially equal and opposite to that imparted by the forward travel of the transplanter over the ground so that the vertical orientation occupied by the blocks at their moment of release will be substantially maintained during their fall into the furrow formed by share 136.

In the particular example illustrated where the assembly is intended to form part of a transplanter of the sort illustrated in the earlier Figures, the resilient pads 113, 114 will typically squeeze the block-embracing portions of the bandolierto a consistent lateral width dimension of 36 mm and the spacing of the side belts 204, 205 might then be set by nip pulleys 207, 208 to 35 mm, say, with 150 mm diameter discharge wheels 210,211 splayed at 165C to give a grip width of 35 mm increasing to 37 mm say at the point of release of the blocks.

By way of clarification, it should be explained that when the nip rollers set the belt spacing to 35 mm, this also results in central regions of the bandolier portions being squeezed in. This in turn causes the end regions of the bandolier portions to expand slightly, in this case to 37 mm. It is these expanded portions that are being gripped by the discharge wheels prior to release.

It will be clear of course that minor modifications of the transplanter illustrated in the earlier Figures will be required if a conveying assembly in accordance with the second embodiment of the invention is to be used in plac. of the one illustrated in those Figures. For example the now unnecessary lost-motion arrangement will preferably be omitted from the transpianter and members 52, 53 will be longer to take account of this. Similarly the share 136 will be more rearwardly located then as shown in Figure 3 so as to take account of the fact that the conveying assembly is now inclined rather than vertical.

As compared with the two-belt (vertical) system of Figure 3, the design of conveying assembly shown in Figures 6 to 9 has the advantage (for outside work) of allowing faster planting speeds. There is also no restriction on the size of plant in the blocks whereas in the two-belt system, the plants should not be too tall or they will continue to be gripped by the belts after their blocks have been released. This will topple the blocks over. The two-belt system however is probably better suited to greenhouse work where the plants will invariably be small enough for the belts to operate satisfactorily and where the feature of having a more compact machine (allowed by having the belt feed vertical) is more important than high planting speeds.

In modifications of the above arrangements, the flat support belt of the second embodiment could be replaced by one or more compactsection belts or by conveyor rollers or conveyor wheels or by a low-friction (e.g. stainless steel) chute, or by any suitable combination of any two or more of these items, e.g. a shortened support belt feeding onto a support chute.

Lastly it needs to be pointed out that although only a single row machine has been described throughout, this could readily be adapted by one skilled in the art to provide a multi-row machine consisting of a number of single-row units either ganged together or individually mounted on a common chassis. In both instances, the operating depth of the units would be set (collectively or individually as the case may be) by pairs of ground-consolidating presser wheels as in Figure 3 closing the furrows around the planted blocks as the machine progresses along the rows.

Obviously any ground wheels present should preferably be in line with the tractor wheels and adjustable for inter-row spacing.

Claims

1. A conveying assembly comprising an array of belts at least two of which are conveyor belts adapted to grip opposite sides of the object to be conveyed so as to discourage relative movement between the object and the belts.

2. An assembly as claimed in Claim 1 in which the conveyor belts are arranged to provide a sufficient grip on the object to be conveyed to support that object.

3. As assembly as claimed in Claim 2 comprising a pair of laterally-spaced flat conveyor belts each reinforced by a respective pair of laterally-spaced compact-section belts running the length of the flat conveyor belts.

4. An assembly as claimed in Claim 3 in which the compact-section belts are woven in and out of successive apertures in border regions of the associated flat belts.

5. An assembly as claimed in Claim 4 in which the belts pass around a pair of waisted and grooved rollers at one end of the assembly and around a pair of parallel-sided grooved rollers at the other end of the assembly.

6. An assembly as claimed in Claim 1 in which the conveyor belts adapted to grip opposite sides of the object to be conveyoed provide insufficient grip on the object wholly to support the object and wherein an additional support means is provided.

7. An assembly as claimed in Claim 8 in which the conveyor belts comprise two side belts arranged to grip opposite sides of the object and the support means provides a support surface underneath the object when so gripped.

8. An assembly as claimed in Claim 7 in which the support means comprises a further conveyor belt or conveyor rollers or conveyor wheels or a chute or any suitable combination of any two or more of these items.

9. An assembly as claimed in any of Claims 6 to 8 in which the two side belts pass around a pair of splayed discharge wheels arranged at the bottom of the assembly to grip and support the object to be conveyed when it reaches the discharge end of the assembly and to release the object only when it is clear of the support means.

10. An assembly as claimed in Claim 9 in which the splay of the discharge wheels is such that the object to be conveyed is released by the wheels at or near the lowest point of travel of the object between the wheels.

11. For use where the object to be conveyed is deformable to a preselected dimension, a conveying assembly as claimed in any of Claims 6 to 10 including, upstream of the conveying belts, a sizing device arranged to press the object to be conveyed to a preselected transverse width dimension which is sufficiently in excess of the lateral spacing of the side belts to encourage the desired gripping action by said side belts.

12. An assembly as claimed in Claim 11 in which the sizing device comprises or forms part of a feed device for feeding the object into the input end of the conveying assembly.

1 3. Apparatus for handling a bandolier as hereinbefore defined when incorporating a conveying assembly according to any preceding claim.

14. Apparatus as claimed in Claim 13 comprising detachment means for detaching an end blockenbracing portion of the bandolier and a conveying assembly according to any of Claims 1 to 12 for feeding the detached end blockembracing portion of the bandolier towards a planting location for the block.

1 5. Apparatus as claimed in Claim 14 when including the limitations of Claim 12 and in which the feed device is provided by feed means for feeding the bandolier to the detachment means so that each successive operation of the detachment means detaches a single end blockembracing portion from the remainder of the bandolier.

16. Apparatus as claimed in any of Claims 13 to 1 5 when including the limitations of any of Claims 2 to 5 wherein the conveying belts of the assembly are arranged to move substantially vertically downwards relative to the chassis of the apparatus.

17. Apparatus as claimed in Claim 16 in which the conveying belts move with a component of horizontal motion to compensate for movement of the apparatus over the ground and encourage the discharged blocks to enter the ground vertically.

18. Apparatus as claimed in any of Claims 13 to 1 5 when including the limitations of any of Claims 6 to 12 in which the conveying assembly is arranged to operate to give the detached portions of the bandolier a component of horizontal motion to compensate for movement of the apparatus over the ground and encourage the blocks to enter the ground vertically.

19. An assembly or apparatus as claimed in any preceding claim and substantially as hereinbefore described with reference to, and as illustrated in, Figures 1 to 5 of the accompanying drawings.

20. An assembly or apparatus as claimed in any of Claims 1 to 18 and substantially as hereinbefore described with reference to, and as illustrated in, Figures 6 to 9 of the accompanying drawings.