DE2039036A1 - Tubular support part for plastic pallets made by blow molding - Google Patents

Description

UNITED GERMAN METAL WORKS Frankfurt, August 4th, 1970

Aktiengesellschaft Hs / WP 6 Frankfurt / Heddernheim
Zeilweg

prov. No. 65 43

Tubular support part for plastic pallets produced using the blow molding process

The invention relates to a together with it adjacent Wall part of a hollow body that is closed on all sides, optionally foamed plastic plate of a plastic pallet produced by the blow molding process up to to rest against the opposite wall, which is flat in the area of the supporting part, and is inserted into the plastic plate Support part.

Support parts of the type mentioned are used by themselves or in a suitable manner Connected to a similar part with single-deck pallets as feet, with double-deck pallets as connecting pieces between the deck and the base plate and result in the insertion of the forks of forklifts or pallet truck required distance between cover plate and floor or cover and floor plate. In on

-2-

Ί09867 / 03'5Ί ^

BATH

known plastic pallets produced by the blow molding process, in which the cover plate or cover and base plate Hollow bodies that are closed in themselves, optionally foamed with plastic, are the strongest load-bearing support parts made of tubular bodies made of metal, plastic or other materials of sufficient load-bearing capacity can be made. It is advantageous to manufacture these support parts from plastic by injection molding and then to connect them to the plastic sheets during or after their deformation. At the junctions between Plastic plates and support parts occur in the generally rough operation and to the extreme limit Forces that act in many different directions and lead to premature damage or destruction the plastic plate or the connection of plastic plate and support part can lead if this connection is not designed appropriately. The purpose of the invention is to make this junction so that Plastic pallets of the type mentioned at the beginning are even more stressful than before and even more carefree treatment can be exposed without it being necessary to increase the wall thickness of the hollow plastic plate and / or other additional measures to reinforce the connection point and the adhesion of the support part to the plastic plate to take.

It is known to design support parts for pallets produced by the blow molding process to be tubular, and to design these tubular support parts to be connected to the hollow plastic plates of the pallet using screw connections, tie rods or the like Utility model 1 958 487) For screw connections

-3-

1 09 8 8 7/0951

of this kind, however, it cannot be ruled out that they loosen during operation and this results in loads that neither the panels nor the supporting parts can cope with are. To a certain extent you can do this

.. **
Evil from constant monitoring additional work. The manufacturing process for these pallets is also more complicated and time-consuming compared to the type proposed, for example, in the German utility model 1 951 976, in which the tubular supporting part is provided with an outer flange at the end to be connected to the plastic plate and this flange together with the one adjacent to it Wall part - the plastic plate is inserted into the plastic plate during the formation of the same until it rests against the opposite wall, which is flat in the area of the support part. This type of manufacture has the advantage that the upper side of the pallet has no dirt holes at the connection point, as is usually the case with the previously mentioned type of fastening. In addition, by molding the flanged pipe end into the hollow plastic plate, a very good and secure anchoring of the supporting part in this plate is achieved. In creep tests under operational stress, however, the inventors found that at high loads the upper side of the plastic plate showed changes ranging from the formation of bulges to the upper wall of the plastic plate being pierced by the support part. In addition, the welded connection between the supporting part and the panel wall loosened, especially in the area of the outer flange, and the inner wall of the plastic panel gave way in the area of the tubular part of the supporting part that dipped into the panel, so that when subjected to a load perpendicular to the panel surface, the supporting part was inclined and underneath high load the pallet collapsed.

^: . : -4- ^: ** remedy it. However, this requires

109Ö87 / Q951

"14-

The object of the invention is therefore to maintain the advantages of the known in the prior art design of the support part and its connection with the Example of a smooth surface of the plastic plate to design a support part that is subject to increased continuous stress and increased load enables permanent connection between plastic plate and support part and through the one Deformation or piercing of the plastic plate by the support part is avoided even under extreme loads.

This object was essentially achieved in that the Support part at the end lying on the other plastic plate has a bottom that closes off the pipe part.

In addition to a significantly better welding of the support part to the plastic plate, a larger Stability of the support part and a higher load capacity of the pallet without the risk of piercing the same through the support part can be reached.

The welded connection in the area of the base of the supporting part has also been significantly improved and intensified that small, preferably pore-like, the soil penetrating ventilation holes distributed over the soil were ordered. The improvement in the welded joint achieved in this way is due to the fact that the ventilation holes prevented the formation of air pockets that can easily form if a Plate made of solid material is placed against a freely hanging sheet of plastic material, as is the case with blowing the plastic plate with simultaneous molding of the support part is required. Since in this case not a very

** inside

109887/0951

high pressure is applied, it is easy possible that the welding of the two parts is prevented from each other.

A particularly advantageous embodiment of the support part according to the invention represents a support part that additionally to the features of the invention described above in the Near the bottom preferably tapered in the entire part immersed in the plastic plate in the direction of the bottom is. A conical taper is most advantageous. This means that the piercing is also possible under extreme loads the plastic plate prevented by means of the support part. In addition, this settles when the support part is inserted in those provided for the formation of the plastic plate Plastic hose this smoothly to the wall of the pipe part so that air inclusions are definitely avoided here too / In addition, the hose wall settles very quickly completely over the rejuvenation, so that at Closing the mold prevents excessive stretching of the Sctilauehmaterials. The wall of the plastic plate is therefore not noticeably weakened, which is one of the reasons for the higher load-bearing capacity of the pallet see is.

Another major improvement of the support part after the Invention is that the bottom of the support part the surface resting on the plastic plate has elevations, which are preferably arranged around a central elevation and form interspaces extending to the edge of the floor, ventilation holes being arranged only in the interspaces. These surveys, which are in Form of cams, intersecting in the center of the floor

-6-

^109887/0951

Ribs or the like can be present, penetrate the Enclose the mold in the still plastic material of the plastic plate and thereby cause it to flow and knead the material of the plate. This considerably intensifies the welding of plate material and Causes bottom of the support part. In addition, the cams provide additional anchoring of the supporting part in the material of the Plastic plate. The extremely good weld when such elevations are arranged is also due to an additional Due to the enlargement of the welded surface.

The carrying part according to the invention carried out with the features described above results in the usual way alone taking place blowing into the plastic plate during the manufacture of the same in the blowing process without additional measures such an intimate and permanent weld connection and such a high load-bearing capacity of the pallet that this can also be exposed to extreme conditions in continuous operation without a disadvantageous change in the support part or the pallet enters. To increase the rigidity of the plastic plate in the area of the supporting part, however, nor around the part of the supporting part which is immersed in the plastic plate, an elevation can be arranged around the circumference of the support part runs, is located in the vicinity of the entry point of the support part into the plastic plate and is advantageous Has breakthroughs. This survey also provides an additional, but not absolutely necessary, anchorage of the supporting part in the plastic plate.

The load-bearing capacity of the supporting part itself can finally also be achieved by profiling the tubular part and / or

-7-

109887/0951

INSPECTED

¹ ■ -7- ■■. '■. ■. ■; ""'' ■ '·

by reinforcing the tubular part and optionally also of the bottom by located inside the tubular part Ribs are raised.

The support part according to the invention can be used for cover pallets can be used as a foot open at the bottom. Is beneficial However, two such support parts at the ends not provided with the bottom to form a self-contained hollow body associate. This can be done, for example, by welding, in particular by mirror welding. Through this the result is a foot (block) of particularly high stability and resilience. In the production of double deck pallets the connection is also designed like the connection with the upper plastic plate. This supporting part, which forms a self-contained hollow body, has opposite the known supporting parts (Blocks) with regard to stability, load-bearing capacity, adhesive strength of the welded connection with the panels of the pallet, Stiffening and stabilization of the pallet connected to it and the like advantages which are suitable for the Blow molding produced the range mentioned at the beginning Species that have not yet found their way into practice, although in particular with regard to their production in to offer considerable advantages in the industrial scale is now able to become a practically usable, to make a technically and economically particularly useful device.

In the figures, the support part according to the invention is shown by way of example and schematically. In the figures, FIG. 1 is a cross section through the support part according to the invention,
Figure 2 is a cross section through support parts according to the invention '

■■ / .. '-8-' ■ '' ■■ ■■■. - ■; ■;

** the lower plate

109887 / 09S1

BAD ORIQfNAL

dung and cross-sections ^ ureb ^ e Te51.ο, one upper and one lower plate of a double-deck pallet, in which the supporting parts with a conical part are planned. a r> en a support part according to the invention and support parts welded to one another according to FIG . , Figure k a section IV-IV through a support part according to Figure? .. Figure 5 is a plan view of part of the bottom of the support part according to the invention with rib-shaped elevations on the bottom,

Figure 6 is a plan view of the bottom of the support member according to the invention with cam-shaped elevations on the bottom. FIG. 7 is a plan view of the bottom of a support part according to the invention with perforated elevations on the pipe circumference.

Figure 8 is a partially sectioned view of a support member according to the invention mil; profiled pipe part. Figure 9 is a partially sectioned plan view along IX-IX on the bottom of the support part according to Figure 8. Figure 10 is a partial cross-section through an open mold for the production of pallet bases in the blow molding process with partially blown-in plastic hose and inserted Support part according to the invention.

Figure 11 is a partial cross-section of the form of Figure 10 in FIG almost closed state.

In FIGS. 1 to 11, 1 is a support part according to the invention with part 3 dipping into plastic plates k when blowing and bottom 2 that comes to rest against the plastic plate 4 and closes off the pipe part 3. Vent holes 10 penetrating this bottom are distributed over the bottom 2 . The part 3 which dips into the plastic plate k can be of cylindrical design. Substantially advantageous

109887/0961 ^ _O h, sinau

However, the conical design of part 3 shown in FIGS. 2 to 11 is more accurate.

On the bottom 2 of the support part 1 can for the purpose of better welding of the bottom 2 with the plastic plate 4 elevations 5, these may have a rib shape like this can be seen in Figure 5 and Figure 9, but they can can also be designed as cams, as FIGS. 6 and 7 show. Of course, any other shape is also possible, provided that it is reasonably evenly distributed over the floor area permitted. To achieve a tight welded connection and to avoid unfavorable stresses in the It is plastic plate and the supporting part embedded in it advantageous if the elevations 5 around a central elevation 6 are arranged in such a way that they form spaces 7 extending to the edge of the bottom 2 * The elevations do not necessarily have to be of the same height; is designed higher than the elevations surrounding or emanating from it 5. In all cases in which such Elevations are arranged on the floor 2, need the Vent holes 10 only in the spaces 7 between to be appropriate to the surveys. Around the circumference of the supporting part 1, an elevation 1f is broken in the area of part 3. This can, for example, in the manner as shown in FIG 7 shown, be provided with openings 12,

It is always in the production of double deck pallets expedient, two support parts 1 according to the invention to the non-bottomed ends 13 together into one to connect self-contained hollow body. This is

-10-

109887 / 09S1

BATH ORIGINAL

ΙΟ-

have therefore expedient '-tv'il by the benefits of the support part come in two plastic plates 4 to advantage, may th Fiel Eindeckpalet the open Endu of Tragteilß nnl-iv circumstances for one pool of rolling elements to form a movable array of iintzen no. However, it is also much more advantageous for these pallets to connect two support parts according to the invention to form a self-contained hollow body ¹ , v / o 11, thereby increasing the stability of the support part. Is considerably increased; will. The connection of the two support parts at the ends 13 is best done by welding, for example using the Spieralschweißverfahren, but it is also, any other type of connection, for example. Connectors, and their combination KLfhvurbindungen possible without substantially compromising the advantages of the supporting part according to uev invention,

Part 3 can also be used inside to increase its stability Provide with reinforcing ribs 9, v / ground. “Such and However, cinematic reinforcement ribbons can also be angry open end 13 are guided,

In Figures 10 and 11, 14 and 15 are the two parts a lockable in the alignment of the arrows of Figure 11 for the manufacture of plastic plates for Plastic pallets in the RI r, s process, 16 is a for the Production of the plate of extnid plastic tubing, which is introduced into the mold 14, 15 immediately after extrusion, as can be seen from FIG. Tn the wall 15 is a supporting part 1, 3 inserted loosely. When the mold moves together, the hose 16 lies down around the part 3 of the support part according to the invention and is made by blowing gas or air into the hose 16

-11-

109887/0951 ^BAD

pressed against this part 3. This pressing takes place in part also through the wall 15 of the mold. After the mold has been opened, the support part adheres firmly to the molded plastic sheet and, once the latter has solidified, it can come together can be removed from the mold with the plastic plate.

After removing the plate 4 from the mold, the molded Support part a second support part, which is also designed, can be fastened in the manner already mentioned above, for example welded on. It is at the ends 13 of the two supporting parts to be welded to one another are not insignificant improvement in the weld achieved if inside each of the support members from the inside of the floor Starting from 2, a concentric tube is formed in the manufacture of the support part, the end of which opposite the bottom 2 is in the same plane as the respective end 13 of the support part. This is advantageous Tube still supported with ribs 9 of the same length as the tube on the inner wall of the tubular part 1,3 or connected to it. As a result, in addition to a significant increase in the stability of the supporting part, the Enlarged welding surface at the ends 13 of the supporting parts, what the improvement of the welded joint can be traced back to.

PATENT CLAIMS

10 9 8 8 7/0 95 1 'bathroom original

Claims (7)

PATENT or .'3CHIJTZANSPRi) CHE Ζιΐί-nminen with the. Him anliegordon ^1r ^ ncH-eil nir-cr h] ;; j rl] - r «i ti _: ^r! fOiiol-.lo.s. ^ pnpr Poh]] * orpc ". ·> ■], '■ -γφ-ί ι (ΐ ^ -ι-ρρ _s ^ τ _β ^ ρ] _{! (} · ^) _ΡΙ ι ^ ipi In? iiR _i '- "- schniiinten KimRtH ■ ffp'lattf- a plastic produced by the binpvpr method , ^ j tubular; 2. Support part according to claim 1, characterized in that small, preferably pore-like ventilation holes (1Π) penetrating the floor are arranged distributed over the floor (2). 3. Support part according to claim 1 or 2, characterized in that it is in the vicinity of the bottom (2), preferably in the saraten Tel immersed in the plastic plate (4)] (3) is tapered towards the bottom (2). 4. Support part according to one of claims 1 to 3, characterized in that that the base (2) has elevations (5) on the surface resting on the plastic plate (4), which are preferably arranged around a central elevation (6) and extend to the edge of the base (2) Form interspaces (7), ventilation holes (10) being arranged only in the interspaces (7) are. -Λ2- 109887/0951 _M0 OHMINAU 5. Support part according to one of claims 1 to'4, characterized in that that around the in the plastic plate (4) ■ ~ immersed part (3) arranged a survey (11) is, which runs around the circumference of the support part (1) near the point of entry of the part (3) into the Plastic plate (4) is located and preferably has openings (12), 6. Support part according to one of claims 1 to 5, characterized in that . indicates that the tubular part (1,3) is profiled ■ is. ■ ... '■ i 7. Tra ^ part. according to one of claims 1 to 6, characterized in that that the tubular part (1,3) and optionally the bottom (2) are reinforced on the inside by ribs (9), H ₁ support part according to one of claims 1 to 7, characterized in that it is connected to a second support part constructed in the same way at the ends (13) not provided with the base (2) to form a self-contained hollow body, 10 9 8 87/0 9 5 1 BATH