Load-Carrying Apparatus and Methods of Manufacture

• US 20080110377A1
• Filed: 03/18/2005
• Published: 05/15/2008
• Est. Priority Date: 03/19/2004
• Status: Abandoned Application

• Current Assignee: Paxxal Inc.
• Original Assignee: Paxxal Inc.
• Inventors: Stevens, Henry
• Application Number:
  US10/593,146
• Publication Number:
  US 20080110377A1
• Time in Patent Office: Days
• US Class Current: 108/51.11
• CPC Class Codes: B29C 2793/009 after shaping
• CPC Class Codes: B29C 41/04 Rotational or centrifugal casting, i.e. coating the inside of a mould by rotating the mould
• CPC Class Codes: B29K 2023/065 HDPE, i.e. high density polyethylene
• CPC Class Codes: B29L 2031/7178 Pallets
• CPC Class Codes: B65D 2203/10 Transponders

Abstract

The invention relates to load-carrying apparatus, for example pallets and shipping containers, rotationally moulded from a plastics material filled with a mineral filler. Methods and apparatus for manufacturing the load-carrying apparatus are also described. In one embodiment, the load-carrying apparatus comprises a pallet formed in two halves as two pallet elements. The plastic, rotationally moulded pallet elements form a nested configuration when stacked in the same orientation, but interlock to form a double-sided pallet when one of the pallet elements is inverted.

Claims

1-231. -231. (canceled)

232. A rotationally-moulded load-carrying apparatus for carrying a load of at least 50 kilograms, wherein the apparatus is manufactured substantially from a filled plastics material comprising:

at least 10% by weight of a polymer; and

at least 25% by weight of a mineral filler material comprising sand; and

at least about 0.1% by weight but less than about 10% by weight unifier.

233. Apparatus according to claim 232, wherein the polymer comprises polyethylene.

234. Apparatus according to claim 232, wherein the filled plastics material comprises at least 25% by weight polymer.

235. Apparatus according to claim 232, wherein the filled plastics material comprises from about 30% to about 70% by weight polymer and from about 70% to about 30% by weight mineral filler material.

236. Apparatus according to claim 232, wherein the filled plastics material comprises at least about 0.25% by weight of unifier.

237. Apparatus according to claim 232, wherein the filled plastics material comprises less than about 5% by weight unifier.

238. Apparatus according to claim 232, wherein the unifier is pre-mixed with the mineral filler material.

239. Apparatus according to claim 232, wherein the unifier comprises an internal lubricant.

240. Apparatus according to claim 239, wherein the internal lubricant comprises a fatty acid amide.

241. Apparatus according to claim 240, wherein the internal lubricant comprises a straight or branched C₁₂-C₂₄ fatty acid amide.

242. Apparatus according to claim 241, wherein the internal lubricant comprises stearamide.

243. Apparatus according to claim 239, wherein the unifier further comprises an external lubricant.

244. Apparatus according to claim 239, wherein the unifier comprises less than 20% by weight internal lubricant.

245. Apparatus according to claim 239, wherein the unifier comprises about 10% by weight internal lubricant.

246. Apparatus according to claim 232, wherein the apparatus is rotationally moulded substantially in one piece.

247. Apparatus according to claim 232, wherein the apparatus comprises a pallet.

248. Apparatus according to claim 247, wherein the pallet comprises a platform and a plurality of feet depending from the platform.

249. Apparatus according to claim 248, wherein the feet of the pallet are regularly spaced over the lower surface of the platform.

250. Apparatus according to claim 248, wherein the feet are arranged to enable lifting equipment to engage the pallet from any one of four directions.

251. Apparatus according to claim 248, wherein at least one foot is arranged substantially at each corner of the platform of the pallet.

252. Apparatus according to claim 248, wherein at least one foot is arranged substantially at the centre of the platform of the pallet.

253. Apparatus according to claim 248, wherein at least one foot is arranged substantially at the centre of each edge of the platform of the pallet.

254. Apparatus according to claim 248, wherein each foot has a recess in the lower surface of the foot.

255. Apparatus according to claim 246, wherein the pallet comprises an outer skin layer having an upper surface and a lower surface.

256. Apparatus according to claim 255, wherein the pallet further comprises an inner layer having a different composition to the outer skin layer.

257. Apparatus according to claim 256, wherein the inner layer comprises a foaming agent.

258. Apparatus according to claim 256, wherein the inner layer comprises at least 40% by weight of a mineral filler material.

259. Apparatus according to claim 255, wherein the outer skin layer comprises more than about 50% by weight polymer.

260. Apparatus according to claim 259, wherein the outer skin layer comprises about 60% by weight polymer.

261. Apparatus according to claim 256, wherein the inner layer comprises about 60% by weight of a mineral filler material.

262. Apparatus according to claim 256 wherein the inner layer comprises a greater amount of filler by weight than the outer layer.

263. Apparatus according to claim 232, wherein the filled plastics material further comprises a pigment.

264. Apparatus according to claim 232, wherein the apparatus incorporates a remotely readable ID tag.

265. Apparatus according to claim 264, wherein the ID tag is moulded into the surface of the apparatus.

266. Apparatus according to claim 233, wherein the polymer comprises high density polyethylene (HDPE).

267. Apparatus according to claim 243, wherein the external lubricant comprises a stearate.

268. Apparatus according to claim 246, wherein the apparatus comprises a pallet.

269. Apparatus according to claim 264, wherein the remotely readable ID tag is an RFID tag.

270. Apparatus according to claim 232, wherein the apparatus is a freight container.