Claims:
I claim
1. A system for making particle boards or the like in which particle slabs or the like are fed into and out of a press comprising, a shelf at an infeed station on one side of a press, a shelf at an outfeed station located on the opposite side of the press, said shelves being generally horizontally aligned with a lower face of a press when the press is open, said shelves being adapted to support flexible carriers, each of said carriers having a first engaging means adjacent one edge thereof, a shuttle mounted for reciprocal movement through the open press between said stations, said shuttle having a spaced pair of second engaging means for simultaneously engaging the first engaging means of a carrier at said infeed station and the first engaging means of a further carrier in said press so that one flexible carrier is drawn from the infeed shelf into the open press and the further carrier is simultaneously drawn from the open press to the outfeed shelf during one reciprocal movement of the shuttle.
2. A system according to claim 1 in which said first and second engaging means are hooks.
3. A system according to claim 1 further characterized by means for lifting said second engaging means to release said second engaging means from the first engaging means.
4. A system according to claim 1, in which said press is multi-layered and each station includes a shelf aligned with each lower face of the press and a said shuttle for each press face, said shuttles being mounted for simultaneous movement between said stations.
Description:
The present invention relates to a method for feeding particle slabs resting on a flexible support surface to and from multi-layer presses, and a system which enables the method to be put into practice.
In accordance with a conventional method for producing fibreboard, particleboard and the like, a number of carriers are arranged to move in a closed circuit and to convey fibre or particle slabs up to and into a hot press in which the relatively thick slabs are pressed to form substantially thinner boards, and to remove the boards from the press, whereafter the boards are removed from the carriers.
With multi-layer presses, one so-called infeed station in normally arranged to serve simultaneously several layers at the input end of the press. The infeed station is filled successively with particle slabs so that the carriers are able to charge all layers of the press simultaneously. At the output end of the press, there is arranged an outfeed station which receives simultaneously all the particle boards or the like discharged from the layers of the press, on the carriers. The infeed and outfeed stations are normally in the form of structures arranged for vertical, reciprocal movement, to facilitate filling and emptying thereof.
Carriers of rigid construction, such as carriers made of sheet metal for example, are normally pushed into the layers of a multi-press with a force applied to the rear of the carriers. In certain instances, however, it is desirable to use carriers of flexible construction, such as metal-wire carriers, for example, wherewith the normal method of pushing the carriers into the press layers cannot be applied.
Apparatus are known, with which flexible carriers supporting particle slabs are passed to a multi-layer press resting on reciprocable support plates. As the support plates are returned from the press opening, gripping means engage the leading edge of the flexible carriers, thereby preventing the carriers from returning with the plates. The carriers are removed from the press by dragging devices located at the outfeed station.
As the support plates are returned from the press, the carriers are deposited gradually on the upper surface of the press plates, which surface is arranged at a distance from the upper surfaces of the support plates corresponding to the thickness of the support plates plus a clearance between each support plate and associated press plate. This results in folding and bending of the slabs, which may damage the same.
Further, with the known apparatus, the passage of the carriers and particle slabs to the infeed station must be interrupted while the support plates are moved into and out of the press. Since the particle slabs are advanced in a relatively dense stream, any interruption in the feed gives rise to complications.
Another disadvantage with known apparatus of the type described is that the press openings must be enlarged by an amount corresponding to the thickness of the support plates moving in and out the presses and the necessary clearance between the support plates and the press plates, since otherwise the presses would be unable to receive particle slabs of relatively large thickness.
The object of the invention is therefore to provide a method and a system with which a number of particle slabs carried on flexible carriers can be charged to and discharged from the separate layers of a multi-layer press in unison, or substantially in unison. To this end, it is proposed in accordance with the invention that the carriers are moved into and out of the press by shuttles arranged to move from a place of rest externally of the press opening in through the press, and to be coupled to the carriers resting on the shelves of the infeed, or outfeed stands and also the carriers located in the press to draw the carriers into and out of the press respectfully. According to the invention, the shuttles are provided with engaging means which engage corresponding engaging means located on the carriers. The manner in which the shuttles and the carriers are coupled together is such as to permit uncoupling thereof by vertical movement of the means supporting the shuttles for reciprocable movement.
The invention will now be described with reference to the accompanying drawings, in which
FIG. 1 illustrates diagrammatically and in side view an embodiment of the mechanism operative in moving the shuttles into and out of a press, which in the illustrated case is a three-layer press,
FIG. 2 illustrates diagrammatically, in side view, means for gripping and shows the outfeed end of the press in a partially enlarged view,
FIG. 3 illustrates diagrammatically and in side view another embodiment of the mechanism operative in moving the shuttles into and out of the press, which also in this case is a three-layer press,
FIG. 4 is a diagrammatic, sectional view of an outfeed station,
FIG. 5 is a plan view of a portion of an exemplary shuttle, and
FIG. 6 is a side view of pivotable attachment means on the rear gripping means, and illustrates more clearly the embodiment illustrated in FIG. 5.
In FIG. 1 there is diagrammatically illustrated an infeed stand or station 1 provided with shelves 2 for supporting carrier means 3. Located adjacent one side of the stand 1 is multi-layer press 4 having press plates 5. The layers of press are indicated by the reference numeral 6, and in the illustrated embodiment are three in number. Arranged on the opposite side of the press to the infeed stand 1 is an outfeed stand or station 7 provided with shuttles 8, which are capable of moving into and out of the press, and shelves 9 which, similarly to shelves 2 of the infeed means, are intended to support carrier means 3. With the embodiment of FIG. 1, the shuttles are supported for reciprocable movement by the outfeed stand 7. The forward ends of the carriers 3 are provided with hook 10 or like means for receiving a rear gripping means 11 and a front gripping means 12 attached to the shuttles 8.
For the purpose of illustration, the layers of the three-layer press depicted in FIG. 1 are shown with the shuttles 8 occupying different operative positions. The upper layers of the press 4 illustrates the position of the shuttle 8 when the press is initially opened. As will be seen from the Figure, when the press is opened the shuttle is located at the outfeed stand 1. Shortly after the press is opened, the shuttles 8 are moved through the press 4 in a manner such that the rear gripping means as seen to the left of the Figure, engage the hooks 10 on the carriers 3 resting on respective shelves of the infeed stand 1 and the forward gripping means the hooks 10 of the carriers located in respective layers of the press, as graphically illustrated in the centre layer of the press shown in FIG. 1. As shown in the lower layer of the press, the shuttles 8 are then activated to move the carriers one step formwards, so that the carriers located in the press are pulled to the outfeed stand 7 and the carrier located on the infeed stand 1 are drawn into the press. Subsequent to moving respective carriers into and out of the press, the outfeed station is lifted slightly, to release the shuttles from the carriers. This illustrated in FIG. 2, which shows in dotted lines the shuttle removed from the carrier 3. When released from the carriers, the shuttles are withdrawn completely from the press, so that the press can be closed and the particle slabs located therein pressed. The shuttles then occupy the position illustrated at the top lay of the illustrated press and the cycle can be repeated. Since the apparatus used for charging and unloading a press of the type envisaged are well known to those of normal skill in the art, as is also the lifting apparatus co-operating with the press feed apparatus, and since such apparatus do not form part of the present invention, they will not be described in detail.
FIG. 3 illustrates an alternative embodiment of the invention. With this embodiment a stationary coveying path 13 is arranged to support an upright post 14 capable of being moved towards and away from the press 4, to insert and withdraw the shuttles 8 into and out of said press. Attached to the post 14 for movement therewith into and out of the press 4 is a coupling device 15, the construction of the device being such that the shuttles 8 are connected to the post 14 at least when drawn from the press and disconnected from the post at least when raising and lowering the stand 7. To permit movement of the post 14 into the outfeed stand 7, the shelves 9 of the alternative embodiment are provided with a slot 16, as shown in FIG. 4.
FIG. 5 is a top plan view of an exemplary embodiment of a shuttle constructed in accordance with the invention. The shuttle comprises a rectangular structure 17 consisting of rectangular iron bar 18 and joining plates 19. Pivotally mounted to respective ends of the shuttle at plates 19 are rear and front gripping means 11 arranged to engage the aforementioned hooks on the carriers 3. The shuttle is also provided with a lug or like member 20, which is engaged by the coupling device 15 co-acting with the moveable post 14. The shuttle may also be reinforced with diagonally extending reinforcing elements.
FIG. 6 illustrates in larger scale the manner in which the rear gripping device 11 of FIG. 5 is pivotally mounted to the plate 19.
The weight of the shuttle 8 of the illustrated embodiment can be lower than the combined weight of the carrier 3 and the particle slab located thereon .