DE10043915A1 - Injection molded body and device and method for its production - Google Patents

Abstract

The invention relates to a single transfer moulded pallet consisting of plastic, especially heavy flowing recycling plastic. Said pallet comprises a deck-like support surface or upper surface (2) and a standing or lower surface (3) which is parallel to said support surface (2) and at a distance from the same. Columnar feet (4, 5) extend in the edge areas of the pallet, between the support surface (2) and the lower surface (3), said feet being connected together at the level of the lower surface by means of skids (7). The feet (4, 5), skids (7) and support surface (2) are embodied as downward opening hollow bodies, the hollow spaces therein being formed by longitudinal and transversal ribbing (8). Insertion holes (13) are provided above the skids (7) and between the feet (4, 5) for the forks of a forklift. The upper side of the upper or support surface (2) is closed above the skids (7), and the pallet (1) comprises an outer surrounding lateral wall (9) which is smooth and closed, except for the insertion holes, in such a way that the ribbing (8) is laterally and outwardly closed. The invention also relates to a device and a method for producing said pallet.

Description

The invention relates to an injection-molded body two decks and a closed edge like plastic pa Latvian, formwork panels and the like according to the generic term of claim 1 and an apparatus and a method ner manufacture.

A plastic pallet is known from EPA-0 2 27 033, which an upper deck with integrally molded on its underside Feet and runners attached to the feet. At the Obersei te of the runners are cones formed in openings from the bottom of the feet of the upper deck trained hollow cylinder stuck in and without additional fasteners are held so that the upper deck of the pallet with the palet tenkufen is connected.

A plastic pallet with an upper deck is known from US Pat. No. 3,664,271 and lower deck known, the upper deck several in one be matched hollow cylinders of a certain height points and the lower deck played an equal number of the grid has hollow cylinders of the same height arranged in a gel-like manner, where the diameter of the hollow cylinder of the two top walls are at least partially sized differently, whereby the hollow cylinder of the lower deck in a form-fitting and frictional manner of the upper deck are stored.

AT-PS 331704 describes a multi-part plastic pallet consisting of an upper deck and a lower deck, the Upper deck is provided with hollow feet that are on the lower deck orderly base plugged and if necessary by welding are firmly connected to the lower deck.  

WO 94/10051 includes a pressed plastic pallet smooth or closed top floor of the upper deck and with a Ribs on the underside of the upper deck are known, Ab pedestals are welded under, which corresponding free spaces for engaging the forks of a forklift or lift roller should form. Run with this plastic pallet Reinforcing ribs on the underside of the upper deck parallel and perpendicular to the pallet side edges, the upper deck in Mirror welding process connected to the spacer bases and the spacers are closed at the bottom and open at the top are designed with internal cross ribbing. With this, The plastic pallets are those formed by the ribbing Cavities of the upper deck closed all around.

The dimensional stability, the strength and the resulting rende durability of the aforementioned, known multi-part plastic pallets is not optimal. The pallet parts some well-known plastic pallets are in a horizontal Level welded together. Other multi-part plastic Pallets are in one plane perpendicular to the load bearing surface the pallet welded together. However, welds show the lack of them becoming brittle after some time, so that the pallet fast compared to pallets without welds it becomes unusable. Another serious disadvantage is that the manufacture of such, composed of several parts placed and welded pallets an important ferti engineering effort means.

A plastic pallet is known from EP-A-400640, which a plug connection for the upper deck and the lower deck has, which is formed in the region of the pallet feet and which has a high pull-out strength, a good connection stiffness against twisting with respect to the perpendicular to the Er aiming for a good transmission of moments from the upper deck to the Lower deck or on the runners of the pallets as well as a good ver binding rigidity achieved against horizontal twisting becomes. In addition, the multi-part design of the  Foot part / foot attachment connection the contact surfaces of the put together th parts enlarged, which keeps these parts together Forces resulting from increased frictional engagement are increased. This two-part plastic pallet has been used proven.

In addition, from DE-PS 15 56 151 is a one-piece, means art made in a single operation known range of fabrics. This skid-free range has an upper deck and a lower part of the same design deck, using to make the pallet from plastic rip Pen and recesses in the upper deck and lower deck so offset are arranged to each other that the ribs of the upper deck over just as long and wide as these cutouts of the Lower decks as well as the ribs of the lower deck are just as long and wide as these sized recesses on the upper deck gen, and where upper deck-lower deck spacers as right angles vertical webs running lig to the ribs are. This well-known plastic pallet is not very resilient, in particular, the inwardly projecting ribs from the upper deck and lower deck by engaging the fork of a fork staplers are easily damaged, so the load capacity of the Pallet is affected.

A similar palette which has a multiplicity of narrow ribs and which can largely be produced using a molding tool is described in US Pat. No. 3,759,194. To form these many narrow ribs, the molds must be designed with a corresponding number of interlocking plate elements, as is shown, for example, in FIG. 4 of US Pat. No. 3,759,194. The production of such molds with many interlocking plate elements is expensive and in operation they are difficult to handle due to their long contact surfaces.

EP 0 572 946 B1 is a one-piece pallet, in particular known from recycled plastic, which is a plate-shaped  Ges support deck and one in a parallel to the level of the support deck and has a standing cover element lying at a spaced level, where from the lower corner areas of the deck to Stand cover element extend columnar feet that in the Stand deck level are braced with each other by skid bars. Where the deck of the deck by the marginal feet and the marginal skid bars formed the outline of the stand cover element with a narrow edge and vertically over each Ku a supporting deck hole is formed in the supporting bridge has the same circumferential contour as the skid bar and which one the feet, the skid bars and the support deck as open at the bottom Hollow bodies are formed. In that the feet, the runners webs and the deck of this known plastic pallet as hollow bodies are formed, the shape of the Pallet can be represented by relatively few such hollow bodies, these hollow bodies each have a considerable area cover richly. With this known palette it is disadvantageous that the runner bars are narrower due to the shaping process are than the pallet feet and therefore less stability exhibit. It is also used to train the skid bars necessary openings in the upper deck on the edge of a web trained, which from one foot to the next pallet foot enough. It has been shown that such webs on pallets the usual loading operations with forklifts not up to the task are because of rough, unforgiving handling of such Pallets are often damaged or destroyed.

To ver such edge-forming openings for runners avoid it is known in injection molding processes by side, sliding elements engaging in the form the area between Cut out the upper deck and skids and the skids to their full width of the feet. The disadvantage here is that the Verrip Openings of the pallet upper decks open outwards, which leads to As a result, this is often full of dirt set and are accessible to pests and also in the long term are no longer usable for hygienic reasons.  

The object of the invention is a one-piece plastic mold body with two decks to create a very high stability and has a low tendency to become dirty.

The task is done with a one-piece molded plastic body solved the features of claim 1.

It is also an object of an apparatus and a method to create the plastic molded body.

The task is carried out with a device with the features of Claim 13 and a method with the features of Claim 34 solved.

Advantageous further developments are in the respective dependent Subclaims marked.

According to the invention, the one-piece molded plastic body has two decks, especially the one-piece plastic pallet ribbed upper deck up to the edges, however the upper deck is closed to the outside all around. Further are none in the peripheral areas from the upper deck to the lower Breakthroughs facing the deck to form skid bars available, so that the upper deck in the edge areas an opti male stability. Furthermore, the skid bars, which the Pallet feet together in the area of a footprint connect until pulled outwards and connect at least the outer feet at essentially full width with each other, so that optimal stability is achieved.

In a further advantageous embodiment, the Plastic pallet above the insertion openings for the forks of a forklift on the upper deck lip protruding upwards against the pen or webs and underneath the insertion openings the outer edge of recessed runners so that such over Pallets stacked one on top of the other easily interlock and counter sideways slipping are secured.  

The device according to the invention provides the runners and the Ribbing over which is closed to the outside with a so-called - known per se from injection molding technology - Shaping sliders in slider technology, with lateral Slide the slider into the closed mold and then be raised. After shaping, these are sliders lowered and extended again so that undercuts or Undercuts - in this case the closed outer wall of the upper deck above the runners - can be generated and yet the shaped body can be completely shaped. Such a technology is inherent in injection molding technology known.

In injection molding technology, these slides are in Slide constructions arranged on the fixed tool plate, because here the constructive and equipment expenditure on a ver reasonable measure can be reduced. In injection molding technology such an arrangement can not be realized because after closing the mold and injecting the plasticized Plastic mass with the movable shape applied a residual stroke is and when arranged on the fixed mold Slider-in-slide construction and a central injection point do this a non-homogeneous distribution of the plasticized plastic mass after application of the remaining stroke. The spritz However, casting technology is used for such large components as pallets, especially if these large components are made in one piece are not applicable at optimal cost. Especially when single Lich a central injection point is provided, the Injection molding technology practically because of the mechanical Expenses too unprofitable due to the very high injection pressures Would lead to machine costs.

In addition, such large, heavily loaded components as Pallets often made from fiber-reinforced plastics, which also with the injection molding technology and the previously mentioned specifications such as the central injection point are not processed can be. In particular, such plastic masses  not in the finest grooves of the shape that will later become the ribs form the pallet, flow.

For example, for the production of a comparable, good plastic molded body in injection molding technology a three times greater locking force than in injection molding technology tigt, in which case 12 to 16 injection points are necessary become. If the material is difficult to flow, especially difficult flowing recycling plastic, the injection molding technology is practical Table not usable at all, because, as already mentioned above leads, the equipment effort to such high injection pressures to be able to realize, would not be economically justifiable.

However, it is also in the method according to the invention and in the inventive device for transfer molding an art molded article not excluded that of the - more common wise - used, central injection point at particularly complex and complicated molded part geometries and multiple injection points are used.

In the molded plastic article according to the invention, in particular A formwork panel or pallet is advantageous in that a Shaped body is created, which is a substantially smooth Upper deck without sensitive side edge areas and on the has full skid bars across the entire width of the feet, so that optimal stability is achieved. Furthermore, the form body with a continuous, smooth side outer surface forms so that contamination by clogging the ribs gears with dirt or the like or pests prevented becomes.

In the device according to the invention and the inventive The procedure is advantageous, taking advantage of the significant Advantages of injection molding technology for the first time the creation of Hin cuts like in injection molding technology for a large one one-piece molding is possible.  

In the following the invention will be explained with reference to a drawing tert. It shows:

Fig. 1 shows a pallet of the invention in a bottom view,

Fig. 2 shows a pallet according to Fig. 1 in a cross section along line BB,

Fig. 3 shows a pallet according to Fig. 1 in a cross section along line AA,

Fig. 4 shows a pallet according to Fig. 1 in a side view,

Fig. 5 shows a pallet according to Fig. 1 in a plan view of the load surface,

Fig. 6 shows a further embodiment of a pallet according to the invention in a bottom view,

Fig. 7 shows a pallet according to Fig. 6 in a cross section along line AA,

Fig. 8 shows a pallet according to Fig. 6, in a plan view of the load surface

Fig. 9 shows a pallet according to Fig. 6 in a perspective plan view of the underside,

Fig. 10 shows an enlarged detail from FIG. 9,

Fig. 11 shows a pallet according to Fig. 6 in a perspective plan view of the top side or the support deck,

Fig. 12 shows an enlarged detail of FIG. 11,

Fig. 13 is a molding device of the invention with an inventive pallet in a half cross section through the tool halves with fully schobe nem slide-in-slide,

Fig. 14 shows a device according to Fig. 13, in which the slide-in-slide is easily pulled out,

Fig. 15 shows a device according to Fig. 13, in which the slider is pulled out further in-vane construction,

Fig. 16 shows a device according to Fig. 13, in which the slider is pulled in Caliper construction in the area of a pallet according to the invention forming cavity completeness, dig,

Fig. 17 shows a device according to Fig. 13 in a teilgeschnit requested plan view of the pallet base for Mende tool from the palette forming hollow space is pulled out slide-in-slide device,

Fig. 18 shows a further embodiment of a slide-in-slide of the mold berkonstruktion in a section through a part of the region of a mold cavity-side sliding Berka nalausgangs,

Fig. 19 is another embodiment of a pallet according to the invention in a perspective view of the upper deck,

Fig. 20 shows a pallet according to Fig. 19, in a perspective view of the lower deck

Fig. 21 is another embodiment of a pallet according to the invention in a perspective view of the upper deck,

Fig. 22 shows a pallet according to Fig. 21 is a perspective view of the lower deck,

Fig. 23 shows a further embodiment of a pallet according to the invention in a perspective top view of the upper deck,

Fig. 24 shows a pallet according to Fig. 23 is a perspective view of the lower deck,

Fig. 25 shows a further embodiment of a pallet according to the invention with a groove-like rounded ribbing of the runners in a partially sectioned perspective view from below.

An inventive plastic molding 1 , such as. B. the pallet 1 ( Fig. 1 to 5) has a plate-shaped square top deck or support deck 2 and a lower deck 3 or deck 3 . On the underside of the support deck 2 , feet 4 are arranged in the edge regions in the corner regions and feet 5 in the edge center regions and in the center of the underside of the support deck 2 a central foot 6 . The feet 4, 5 and 6 are square or rectangular in cross section and extend from the supporting deck 2 perpendicular to a plane parallel to the plane of the supporting decks 2 plane of the stand decks. 3 In the standing deck level, the feet 4 and 5 are connected to one another transversely along the edge of the pallet via skid bars 7 . The runner webs 7 have a width which essentially corresponds to the width of the feet 4 , 5 or are just as wide as the feet.

To reduce weight and to increase the connection stiffness and stability, the essential elements 2 , 3 , 4 , 5 , 6 , and 7, from which the pallet 1 is formed in one piece, are hollow and open at the bottom and have cross in a manner known per se - And longitudinal webs 8 , which form a cross and cross ribbing and accordingly support and stiffen the walls of the elements. Accordingly, the feet 4 , 5 and 6 have continuous webs 8 in the form of a lattice structure at the full height of the feet. The shaped U-cross section runner webs 4 are connected in the longitudinal direction and / or transverse direction of the Ku fenstege extending ribs or ridges 8 are formed, and also widely stretched cross-sectionally U-shaped plate of the supporting deck 2 the lower side has transverse ridges 8, structure also in mesh, on.

In a first embodiment ( Fig. 5) the upper deck upper side 2 is flat and smooth without openings ( Fig. 5), with the exception of lateral openings 13 between the feet 4 , 5, the pallet has a circumferential smooth side outer surface 9 . The side openings 13 serve as insertion holes 13 for forks of a forklift.

In a preferred embodiment ( Fig. 9 to 12), the runner webs 7 are formed in the region of the insertion holes 13 opposite the circumferential side surface 9 of the pallet 1 of each foot 4 , 5 with a step 10 relative to the outer surface slightly set back edge 11 , whereby aligned on the edge side above the edge 11 or the insertion hole 13 on the top of the supporting deck upwardly projecting narrow lips 12 or webs 12 are formed, so that stacked pallets are secured against lateral slipping of individual pallets in that the lips 12 or webs 12 protrude into the recessed area of the runner webs 7 of the next pallet and rest on the edge 11 .

In a further embodiment of the pallet according to the invention ( FIGS. 6 to 8), skid webs 14 are formed from the feet 5 to the central foot 6 , support deck holes 15 being arranged which extend above the skid webs 14 from the central foot 6 to the outer feet 5 and the formation of the runners 14 by the upper die of the mold.

In further embodiments of the pallet according to the invention ( FIGS. 19 to 24), recesses 77 or recesses 77 are arranged in the outer feet 4 , 5 , so that the surfaces of the feet are partially or completely recessed relative to the outer surface of the pallet. Back jumps or recesses can only be arranged in the corner feet ( Fig. 19 and 20), these recesses extending around the corner, but are not arranged in the feet 4 over the entire surface. Furthermore, in the case of corner feet designed in this way, the feet 5 which are in the middle of the edge can be provided with continuous recesses or recesses 77 (FIGS . 21, 22). Fer ner, it is possible to see the recesses 77 both in the outer or corner feet 4 and in the edge center feet 5 over the entire surface ( Fig. 23, 24).

In a further advantageous embodiment of the plastic molded body 1 ( FIG. 25), the runner 7 has a ribbing 8 , the ribs 8 of such a runner 7 with curves 8 a passing into a bottom wall 7 b, so that trough-like elongated grooves 8 b be formed. In one of the like embodiment of the ribs 8 of the runners 7, it is advantageous that such runners or these channels can become less contaminated and are much easier to clean. Plastic moldings, in particular pallets with such gutters, are therefore preferably used in the field of food technology.

The device according to the invention for injection molding the pallet according to the invention (FIGS . 13 to 17) essentially corresponds to the shaping region 30 of a conventional device for injection molding plastics. The device has a mold frame (not shown) with two - for example upright - plate-shaped mold table tops 31 , 32 , which are arranged opposite one another with flat sides 33 . An injection device (not shown) facing the tabletop 31 serves as a fixed tabletop 31 , on the flat side 33 of which a mold 34 is arranged , in particular for molding the upper deck of a pallet 1 according to the invention. The tabletop 31 and the molding tool 34 have an axial central recess 36 (only half shown in the figures) along a longitudinal axis 35 , which corresponds to the injection direction for plastic, which is adapted to the outer shape of an opening of an injection nozzle to such an extent that a A spray nozzle perpendicular to the plate plane in the mold table top 31 and the mold 34 can be arranged at rest. A front edge 37 of the recess 36 or the mouth 38 of the recess 36 is flush with the inner surface 39 facing the pallet or the molded part. With respect to the longitudinal axis 35 , opposite the molding table plate 31 or the molding tool 34 , the movable molding table 32 is arranged with a corresponding molding tool 40 facing the molding tool 34 . On its side facing away from the molding tool 40 , the molding table 32 is connected to a crosshead, not shown, via a hydraulic drive for closing and opening the mold.

The forming tool 40 can be moved with the movable forming table 32 towards and away from the corresponding corresponding forming tool 34 . The entire mold area or mold frame is firmly connected to a base plate or a building foundation (not shown). The movable mold 40 ( Fig. 15, 19) is with respect to its outer contour or be with respect to its surface contour to form the underside of the upper deck 2 and the lower deck 3 or the feet 4 , 5 , 6 and the undersides of the skid bars 7 , 14th educated. In the areas between the feet 4 , 5 or in the area of the entry holes 13 below the upper deck 2 and above the skid bars 4 of a pallet to be manufactured, 40 slide devices 45 are arranged on the side of the movable mold. The pusher means 45 comprise a valve housing 46 with a sliding berkanal 47 as well as a longitudinally displaceable in the slide channel 47 slide 48 and a slide moving means 49. The slide housing extends essentially over the height of the molding tool 40 and at least over the width of the pallet from a corner foot 4 on one side to the next corner foot 4 on the same side ( FIG. 19, representation of a quarter shape). In the slider housing 46 , a slide channel 47 is formed, which is flat rectangular in cross section with respect to the forming table surface 33 or the clamping plane of the molding tool 40 .

At the, the die 40 opposite end of the slide channel 47 , the slide movement device 49 is formed on the slide housing 46, in particular in the form of a hydraulic piston cylinder unit 51 with an actuating cylinder 52 and a piston 53 retractable into the slide channel 47 .

In the slide channel 47 of the slider 48 is arranged, the slider 48 has a rectangular guide portion 54 and a shaping area 55th The guide region 54 is arranged with respect to the molding tool 40 behind the shaping region 55 . In the top view ( FIG. 19), the shaping region 55 has, in accordance with the shape of the recess ( 13 ) to be formed in the side of the pallet ( 1 ), an underside 56 which forms the upper part of the runner, in particular a smooth underside 56, and an upper underside 2 or upper deck Cross and longitudinal webs 8 forming profiled top 57 , and the side walls of the feet 4 , 5 forming and the bottom and top connecting side walls 58 . In the upper side 57 of the shaping area 55 , grooves 59 are introduced in accordance with the ribs 8 of the upper deck. In order to form the curves of the feet 4 , 5 , the shaping area 55 tapers from the guiding area 54 with transition radii 60 . The slider 48 is formed in two parts from a slider upper part 61 and a slider lower part 62 . The piston 53 of the piston-cylinder unit 51 is arranged on the rear on the rear 63 b of the lower slide part 62 . The lower part 62 tapers to the shaping area 55 linearly, while the upper part 61 thickens in accordance with the tapering of the lower part 62 , so that the lower part 62 forms a slope down to the shaping area 55 ramp 62 b. In a lateral sectional view ( FIG. 13), the upper slide part 61 and the lower slide part 62 each form a mutually corresponding, substantially prismatic shape.

In the area of the guide area 54 , the upper slide part 61 has a locking bar 64 which is rectangular in cross-section and ends with the rear side 63 a of the slide, facing away from the lower part 62 . Toward the molding tool 40 , the upper slide part 61 and the lower slide part 62 each have a front wall 65 , 66 . In the slide channel 47 , a locking groove 67 corresponding to the locking bar 64 is arranged with a groove bottom 68 and groove side walls 69 . The locking groove 67 is such net angeord in the slide channel, that the locking bar 64 can engage the slider shell in the fully inserted slide into the locking groove 67th

In a further embodiment ( FIG. 18) of the slide-in-slide construction, instead of a locking groove 67 in the region of a front groove side wall 69, a stop step 80 running transversely on the upper side of the slide channel 47 is provided for the locking bar 64 . In order to achieve a lock, this embodiment has a yellow yellow hydraulic latch 81 or a hydraulic latch bar 81 which, after the slide 48 has been fully inserted into the mold behind the latch bar 64, is inserted into the slide channel 47 such that it is on a rear side 63 a of the slide upper part 61 abuts.

The upper slide part 61 and the lower slide part 62 are slidably arranged on one another, a guide, for example a dovetail guide or T-guide, being present between the upper slide part 61 and the lower slide part 62 such that the upper slide part 61 on the lower slide part 62 up to a defined, by which Guide certain stop free way the ramp 62 b can slide down.

The shaping tool 40 has an area 70 for shaping the underside of the runners and an area 71 for shaping the underside of the upper deck, a step 72 having an outwardly facing wall 73 being formed between the shaping area 70 and the shaping area 71 .

The following is the operation of the invention direction for injection molding a one-piece plastic pallet explained.

In the initial state ( FIG. 16), the slider 48 is completely drawn into the slider channel, the upper slider part 61 on the ramp 62 a of the lower slider part 62 up to a stop, not shown, in the sliding guide, in particular a dovetail guide or T-guide, the ramp 62 a slips down. In this state, the lock bar 64 is located on an upper side with at a wide Schieberkanalinnenwandung while the slide base 62 with a ramp 62 b opposite surface of the guide portion on the gegenüberlie constricting wide inside wall of the slider channel 47 is present.

In order to prepare the mold 30 for the production of a pallet, the slide 48 with the piston 53 of the piston-cylinder unit is moved into the area forming the pallet 1 until a front wall 65 of the upper slide part 61 on the wall 73 or step 72 of the movable molding tool 40 abuts. In the sem state, the lock bar 64 are aligned and the Verrie gelungsnut 67, so that the locking bar 64 just below the locking groove 67 is located. When the slide 48 or the piston 53 is pushed in further, the slide lower part 62 also comes into the region of a plug-in hole 13 to be provided on the pallet 1 , the slide upper part, since it already abuts the wall 73 , slides along the ramp 62 a and is lifted up so that the locking bar 64 enters the locking groove 67 .

When the slide 48 is fully inserted, the Vorderwan applications 65 , 66 of the upper slide part 61 and the lower slide part 62 abut against the wall 73 or step 72 . The locking bar 64 is completely in the locking groove 67 .

The walls 69 of the locking groove 67, but at least the shape of the wall 40 facing away from 69 the locking groove 67 are preferably designed in such a way diagonally to the groove base 68, the groove 67 that at the bottom of the groove 68 tapers. This creates a pressure of the slider top portion 61 dung at the insertion of the locking bar 64 into the locking groove 67 with its Vorderwan achieved against the wall of 73 65, so that in the region of the con tact surface between the slider upper part and mold the Pres solution is so high that no plastic material in can penetrate this area and form a skin.

In one embodiment with a hydraulic locking slide or a hydraulic locking bolt 81 , the locking bolt 81 or the locking bar 81 is inserted through an opening 82 in the sliding box 46 into the sliding channel 47 behind the locking bar 64 until the locking bolt 81 or the locking bar 81 comes to lie behind the locking bar 64 of the slide upper part 61 . Preferably, with the at the back 63 a of the locking bar 64 adjoining hydraulic locking bar 81 or the hydraulic locking bolt 81, a pressure of the slide upper part 61 with its front wall 65 against the wall 73 of the mold is achieved, so that in the area of the contact surface between the upper slide part and Mold the pressure is so high that no plastic material can penetrate into this area and form a skin.

Then or in the process, the mold halves 34 , 40 are moved towards one another in such a way that the mold is closed and a cavity is formed, into which plasticized plastic compound is then injected through the mouth 38 .

After the mold has been filled to a predetermined extent, the two mold halves 34 , 40 are moved further towards one another, as a result of which the plasticized plastic compound is also pressed in the mold and this causes even the finest grooves, for example also the grooves 59 of the slide upper part 61 to flow into it. After the plasticized plastic mass in the mold - which is in particular cooled - solidifies, the piston 53 is moved out of the sliding housing 46 , whereby the lower slide part 62 is pulled out of the area of a shaped insertion hole. As a result, the sliding upper part 61 slides down the ramp 62 a in the dovetail guide or T-guide or is pulled out of the locking groove by pulling back the lower part 62 of the slide. After the upper slide part with its locking bar 64 is completely dig out of the locking groove 67 , the upper slide part 61 preferably slides a short distance in the guide down the slope 62 a until an end stop is reached.

In an embodiment with a hydraulic locking via a hydraulic locking bolt 81 or a locking bar 81 , the slide lower part 62 is moved out of the mold and the hydraulic bolt 81 is moved out of the slide channel 47 at least a little in order to press the slide upper part against the wall 73 relieve pressure so that the locking bar 64 can slide out of the space between the bolt 81 and the stop edge 80 , analogously to a locking slot. In addition, it is also possible to pull the bolt 81 completely out of the slide channel 47 , but it is expedient here to wait until the slide upper part 61 with its grooves 59 has been completely pulled down so far that the ribs 8 formed are no longer in the area of the grooves 59 , since otherwise pulling out could damage the ribs.

Subsequently, the upper slide part 61 with the lower slide part 62 is completely moved into the slide channel 47 . After the slide upper part has been moved out of the area of the entry holes 13 , the pallet can be shaped. The stroke or the lowering of the upper slide part 61 , caused by the ramp 62 and the positive guidance on the lower slide part 62, is dimensioned such that the upper slide part, after forming the pallet, emerges from the area of the Verrip pung 8 that the ribs 8 , which are formed by the grooves 59 of the slide upper part, come completely out of these grooves. This technique makes it possible to form undercuts, in this case the ribs 8 , which are formed by the grooves 59 , and nevertheless form bodies with such undercuts, in particular a circumferential, smooth outer wall 9, in the injection molding process.

In the molded plastic body according to the invention such as a pallet te, formwork panel or the like, is advantageous in that this shaped body one particularly in the sensitive randbe rich closed outer wall and a smooth top deck has, which is above the runners or the No holes to the side formed by the ribbing has opening cavities. This will create a palette with optimal stability, which also little dirt is susceptible because the ribbing is open at the bottom and from is not easily accessible from the outside. Such a form So far, it was not possible to manufacture the body because such complex hints Cuts in the injection molding process are not made could.

In the case of the molded plastic articles according to the invention, such as pallets with recesses 77 or recesses in the corner or edge centers 4 , 5, it is advantageous that they enable improved fixation of foils on such pallets, for example shrink foils.

In molded articles according to the invention in which above the one slots for the forks of a forklift on the upper deck lips or ridges protruding upwards and below the Insert openings slightly set back against the outer edge Skids are arranged, it is advantageous that such match other stacked moldings easily interlock and counter sideways slipping are secured.  

In the device according to the invention and the inventive The method is advantageous in that it is stable in a simple manner Plastic molded body with a closed in the edge areas NEN upper deck can be generated, but still in the area of Insertion holes for the forks of a lifting tool runners, in front can preferably be produced over the entire width of the feet.

Claims (50)

1. One-piece, injection-molded body, in particular pallet, formwork panel or the like, made of plastic, in particular made of recycled plastic, with a plattenför shaped supporting or upper deck ( 2 ) and a to the level of the supporting deck ( 2 ) parallel and spaced stand or Lower deck ( 3 ), with column-shaped feet ( 4 , 5 ) extending in the edge areas from the supporting deck ( 2 ) to the lower deck ( 3 ), which are connected to one another in a lower deck level by skid bars ( 7 ), the feet ( 4 , 5 ), the runner webs ( 7 ) and the supporting deck ( 2 ) are designed as hollow bodies open at the bottom, the cavities of which are formed with a longitudinal and transverse ribbing ( 8 ), above the runner webs ( 7 ) and between the feet ( 4 , 5 ) there are entry holes ( 13 ) for the forks of a forklift, characterized in that
the top of the upper or support deck ( 2 ) above the skid bars ( 7 ) is closed and
the pallet ( 1 ), except for the entry holes ( 13 ), has a smooth, closed side wall ( 9 ) running around the outside, so that the ribbing ( 8 ) is closed to the side on the outside. 2. Shaped body according to claim 1, characterized in that feet ( 4 ) are arranged in the corner areas. 3. Shaped body according to claim 1 and / or 2, characterized in that in the center between the corner feet ( 4 ) of two parallel edges ver running edges at least one further foot ( 5 ) is arranged, whereby each edge two entry holes ( 13 ) in the side wall ( 9 ) are formed. 4. Shaped body according to one or more of the preceding claims, characterized in that a further foot ( 6 ) is integrally formed on the underside of the supporting deck ( 2 ), which extends into the plane of the lower deck ( 3 ). 5. Shaped body according to claim 4, characterized in that from the central foot ( 6 ) runner webs ( 14 ) to the marginal feet ( 5 ) and / or the corner feet ( 4 ) are arranged extending. 6. Shaped body according to claim 5, characterized in that above the skid webs ( 14 ) supporting deck holes ( 18 ) are formed in the supporting deck. 7. Shaped body according to one or more of the preceding claims, characterized in that the runner webs ( 7 , 14 ) are formed with ribs ( 8 ) extending in the longitudinal direction and / or transverse direction of the runner webs. 8. Shaped body according to one or more of the preceding claims, characterized in that the upper deck ( 2 ), the feet ( 4 , 5 , 6 ) and the skid bars ( 7 , 14 ) at full height continuous ribs ( 8 ) in the form of a lattice structure exhibit. 9. Shaped body according to one or more of the preceding Expectations, characterized in that the Shaped body from a fiber or mineral reinforced art fabric is formed. 10. Shaped body according to one or more of the preceding claims, characterized in that in the corner feet ( 4 ) and / or in the center between the corner feet ( 4 ) arranged edge feet ( 5 ) an outwardly white recess ( 77 ) or a recess ( 77 ) for film fixation is arranged. 11. Shaped body according to claim 10, characterized in that the recesses ( 77 ) or recesses ( 77 ) on the outside are completely flat or in some areas on the feet ( 4 , 5 ) the IN ANY. 12. Shaped body according to one or more of the preceding claims, characterized in that the runner webs ( 7 ) on the underside have ribbing ( 8 ) with relatively far apart parallel ribs ( 8 ), the ribs ( 8 ) with curves or Arches ( 8 a) pass into the runner floor ( 7 b) so that elongated trough-like grooves ( 8 b) are formed between the ribs ( 8 ). 13. Device for producing an injection-molded, one-piece molded body with two decks, in particular for producing a molded body according to one or more of the preceding claims, wherein an injection device with an injection nozzle ( 38 ) and a shaping unit formed from at least two molding tools ( 34 , 40 ) ( 30 ) is present, the shaping unit ( 30 ) having a fixed mold ( 34 ) and a movable, movable mold ( 40 ), characterized in that on the movable mold ( 40 ) in the region of in a side wall ( 9 ) a pallet (1) to be provided Einfahrlöchern (13) at least one pusher means (45) with at least one retractable side in a mold cavity, the two-part slide (48) is provided, wherein the slider (48), a slider top (61) and a slide base (62 ) and the upper slide part ( 61 ) of the lower slide part ( 62 ) in the form height lraum is arranged in a raised mold position and a lowered demolding position is movably actuated. 14. The apparatus according to claim 13, characterized in that the slide means ( 45 ) have a slide housing ( 46 ) with a slide channel ( 47 ) and the linearly displaceable slide ( 48 ) in the slide channel ( 47 ) and a slider movement device ( 49 ). 15. The apparatus according to claim 13 or 14, characterized in that the slide housing is substantially over the height of the mold ( 40 ) and at least over the width of the pallet te from a corner foot ( 4 ) on one side to the next corner foot ( 4 ) on the same side extends. 16. Device according to one of claims 13 to 15, characterized in that the slide channel ( 47 ) in the slide housing ( 46 ) is designed such that the slide channel ( 47 ) with respect to the mold table surface ( 33 ) or the clamping plane of the mold ( 40 ) is flat rectangular in cross section. 17. The device according to one of claims 13 to 16, characterized in that the slide channel has a mold-side opening and a counter-mold-side opening, the slide movement device ( 49 ) being arranged on the counter-mold-side opening on the slide housing ( 46 ). 18. The apparatus according to claim 17, characterized in that the slide movement device ( 49 ) is a hydraulic movement device with a piston-cylinder unit ( 51 ), with an actuating cylinder ( 52 ) and a channel ( 47 ) retractable piston ( 53 ). 19. Device according to one of claims 13 to 15, characterized in that in the slide channel ( 47 ) the slide ( 48 ) is arranged to be longitudinally displaceable, the slide ( 48 ) having a cuboidal guide region ( 54 ) on the inner walls of the slide channel ( 47 ) and has a shaping region ( 55 ). 20. Device according to one of claims 13 to 19, characterized in that the guide region ( 54 ) is arranged in relation to the molding tool ( 40 ) behind the shaping region ( 55 ) and has a cross section which essentially corresponds to the cross section of the slide channel. 21. Device according to one of claims 13 to 20, characterized in that the shaping region ( 55 ) corresponding to the shape of the recess ( 13 ) to be formed in the side of the shaped body ( 1 ) or the pallet ( 1 ) forms a top of the runners, in particular smooth underside ( 56 ) and a profiled upper side ( 57 ) forming the upper underside of the deck or upper decks transverse and longitudinal webs ( 8 ) and the side walls of the feet ( 4 , 5 ) forming the underside ( 56 ) and upper side ( 57 ) has connecting side walls ( 58 ). 22. Device according to one of claims 13 to 21, characterized in that in the upper side ( 57 ) of the shaping region ( 55 ) corresponding to the ribs ( 8 ) to be formed on the underside of the upper deck, grooves ( 59 ) are introduced. 23. Device according to one of claims 13 to 22, characterized in that the shaping region ( 55 ) from the guide region ( 54 ) with transition radii ( 60 ) in the side walls ( 58 ) tapers to round the feet ( 4 , 5 ) of the molded body ( 1 ) or the pallet ( 1 ). 24. The device according to one or more of claims 22 to 23, characterized in that the piston ( 53 ) of the piston-cylinder unit ( 51 ) is arranged on the rear side on the rear side ( 63 b) of the lower slide part ( 62 ). 25. The device according to any one of claims 13 to 24, characterized in that the slide lower part ( 62 ) tapers linearly from the guide region ( 54 ) to the molding region ( 55 ), the upper slide part ( 61 ) corresponding to the taper of the lower slide part ( 62 ) thickened so that the bottom part of the slide ( 62 ) forms a ramp ( 62 b) falling towards the shaping region ( 55 ). 26. Device according to one of claims 13 to 25, characterized in that in the loading area of the guide area ( 54 ) the slide upper part ( 61 ) with the upper part rear side ( 63 a), from the lower slide part ( 62 ) pointing, cross-sectionally rectangular locking bar ( 64 ). 27. The device according to one of claims 13 to 26, characterized in that the slide upper part ( 61 ) and the lower slide part ( 62 ) towards the molding tool ( 40 ) each have a front wall ( 65 , 66 ). 28. Device according to one of claims 13 to 27, characterized in that a locking groove ( 67 ) with a groove bottom ( 68 ) and groove side walls ( 69 ) corresponding to the locking strip ( 64 ) is arranged in the slide channel ( 47 ), the locking groove ( 67 ) is arranged in the slide channel in such a way that the locking bar ( 64 ) of the sliding upper part can engage in the locking groove ( 67 ) when the slide is fully inserted into the mold cavity. 29. The device according to claim 28, characterized in that the walls ( 69 ) of the locking groove ( 67 ), but at least the wall ( 69 ) facing away from the mold ( 40 ) of the locking groove ( 67 ) preferably obliquely towards the groove bottom ( 68 ) is formed that the groove ( 67 ) tapers to the groove bottom ( 68 ), whereby upon insertion of the locking bar ( 64 ) into the locking groove ( 67 ) a pressure of the upper slide part ( 61 ) with its front wall ( 65 ) against a step wall ( 73 ) of the mold ( 40 ) is achieved so that in the area of the contact surface between the upper slide part ( 61 ) and the mold ( 40 ) the pressure is so high that no plastic material can penetrate into this area and form a skin. 30. Device according to one of claims 13 to 27, characterized in that in the slide channel ( 47 ) there is a stop edge ( 80 ) corresponding to the locking bar ( 64 ), the stop edge ( 80 ) being arranged in this way in the slide channel ( 47 ) that the locking bar ( 64 ) of the upper slide part ( 61 ) rests against the stop edge ( 80 ) when the slide is fully inserted into the mold cavity and that a hydraulic locking device ( 81 ) in the form of a locking bolt ( 81 ) or a locking bar ( 81 ) is present, which is completely inserted into the mold cavity slide, based on the stop edge ( 80 ), behind the locking bar ( 64 ) of the sliding upper part ( 61 ) on a slide upper part rear side ( 63 a) is arranged adjacent. 31. The device according to one of claims 13 to 30, characterized in that the upper slide part ( 61 ) and the lower slide part ( 62 ) are arranged to slide on one another, a guide being provided between the upper slide part ( 61 ) and the lower slide part ( 62 ) in such a way that that the upper slide part ( 61 ) on the lower slide part ( 62 ) can freely slide down the ramp ( 62 b) up to a stop predetermined by the guide. 32. Device according to claim 31, characterized in that the Leadership a forced tour like a backdrop, swallows tail guide or T guide. 33. Device according to one of claims 13 to 32, characterized in that the lifting or lowering of the upper slide part ( 61 ), caused by the ramp ( 62 b) and the positive guidance on the lower slide part ( 62 ) is dimensioned such that the After forming the pallet, the upper part of the slide emerges from the area of the ribbing ( 8 ) so that the ribs ( 8 ), which are formed by the grooves ( 59 ) of the upper part of the slide, come completely out of these grooves, after which the upper part of the slide with its locking bar ( 64 ) completely out of the locking groove ( 67 ) or the area of the stop edge ( 80 ) and the hydraulic locking device ( 81 ), the sliding eroberteil ( 61 ) a short distance in the guide the slope 62 a to can slide to an end stop so that a safe unlocking can be guaranteed. 34. A method for injection molding a one-piece plastic molding, in particular a plastic molding according to one or more of claims 1 to 12, in particular using a device according to one or more of claims 12 to 33, wherein plasticized plastic mass in one of two molds ( 34 , 40 ) formed mold cavity is injected and then the one movable mold ( 40 ) for applying a pressure to the other, fixed mold ( 34 ) is moved, and after the plastic mass has solidified, the mold halves or molds ( 34 , 40 ) Demoulding of the pallet are moved apart, characterized in that, in order to form a rib ( 8 ) of a pallet upper deck ( 2 ) which is open at the bottom and closed at the side, above a skid webs ( 7 ) before the plastic compound is injected, an arranged on the movable molding tool ( 40 ) two-part slide ( 48 ) is inserted laterally into the mold cavity and an upper slide part ( 61 ) is moved or lifted in the direction of the fixed mold ( 35 ) into a position that forms the ribs and after the plastic mass has hardened from the area of the ribs in the direction of the fixed mold ( 35 ) moved away or lowered and extended out of the mold cavity to the side. 35. The method according to claim 34, characterized in that the slide upper part ( 61 ) is locked in the raised position on the slide housing ( 48 ). 36. The method according to claim 34 and / or 35, characterized in that the slide lower part ( 62 ) cooperates with a stop step ( 72 ) or wall ( 73 ) in the mold ( 40 ) such that the upper slide part after the stop with one in front of it Wall ( 64 ) is raised at the edge ( 72 ) of the lower part of the slide, the lower part of the slide being moved further into the mold cavity when it is lifted, until it also has a front wall ( 65 ) on the step ( 72 ) or wall ( 73 ) of the mold ( 40 ) strikes. 37. The method according to any one of claims 34 to 36, characterized in that after the stop at the step ( 72 ), the upper slide part is lifted and locked by sliding up and on a ramp ( 62 b) formed on the lower slide part ( 62 ). 38. The method according to any one of claims 34 to 37, characterized in that the slide upper part ( 61 ) engages when lifting with a locking projection ( 64 ) in a locking recess ( 68 ) of the slide housing ( 45 ). 39. The method according to claim 38, characterized in that a locking bar ( 67 ) engages in a locking groove ( 68 ). 40. The method according to any one of claims 34 to 37, characterized in that for locking the locking projection ( 64 ) strikes at a stop edge ( 80 ) in the slide channel and on the opposite side of the locking bar ( 64 ) a hydraulically actuated locking device ( 81 ) Locking bar ( 64 ) engages behind. 41. The method according to claim 40, characterized in that the hydraulic locking device ( 81 ) exerts pressure on the slide upper part ( 61 ) with its front wall ( 65 ) on a mold wall ( 73 ) in such a way that between the slide ( 48 ) and mold wall ( 73 ) no plastic can flow. 42. The method according to any one of claims 34 to 40, characterized in that the Slide is cooled. 43. The method according to claim 42, characterized in that the Slider is cooled inside. 44. The method according to claim 42 and / or 43, characterized in that the Slider is liquid cooled. 45. The method according to any one of claims 34 to 44, characterized in that the Plastic mass inserted through a single injection opening is injected. 46. The method according to any one of claims 31 to 39, characterized in that the Plastic mass inserted through several injection openings is injected. 47. The method according to any one of claims 31 to 40, characterized in that fiber or mineral-containing plastic mass is injected. 48. The method according to any one of claims 31 to 41, characterized in that for pulling the slide ( 48 ) out of the mold cavity, the slide lower part ( 62 ) is first drawn into the slide channel, the slide upper part sliding down the ramp ( 62 b) and out of the Locking groove and the ribs of the pallet is pulled out and, after the locking bar has come out of the locking groove or the loading area between the stop edge ( 80 ) and hydraulic locking device ( 81 ), is lowered a little further until a stop in a guide between Upper part of the slide and lower part of the slide is reached, whereupon the lowered upper part of the slide is completely drawn into the slide channel with the lower part of the slide. 49. The method according to any one of claims 34 to 48, characterized in that the Upper part of the slide with a sliding guide on the lower part of the slide is kept partially movable. 50. The method according to claim 49, characterized in that the Slider upper part with a dovetail guide or T-guide on the lower part of the slide slidably supported will.