US2942825A

US2942825A - Load supporting pallet

Info

Publication number: US2942825A
Application number: US588780A
Authority: US
Inventors: Trapp Carl Ake
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-06-10
Filing date: 1956-06-01
Publication date: 1960-06-28
Anticipated expiration: 1977-06-28

Description

June 2'8, 1960 c. AKE TRAPP LOAD SUPPORTING PALLET Filed June 1, 1956 IlfuHrILmlllLlrr M n 2.1L

P www rn me# Vo/K NA/ hM/m /Wnn C United States Patent O 2,942,825 LOAD SUPPORTING PALLET Carl ke Sigurdsvagen 27, Bromma, 'Sweden Filed June 1, 1956,75. No.ss's,'1so Claims priority, application Sweden June 10, 1955 1 claims. (ci. :4s-1z0) The present invention relates .to a load supporting pallet consisting of an upper board layer, a lower board layer and spacer members inserted between said layers. Y

In assembling such pallets it is known to use nails, rivets or bolts, which often project wholly through the members laid upon each other. Said connecting members usually do not protect the boards -from being split due to drying of .the wood or rough handling, but on the contrary they often contribute to splitting on account of their wedge action. It has been suggested to prevent splitting by wrapping the boards with iron bands, but after a relatively slight upsetting of the wood at the edges of the boards due to careless handling, said bands become inoperative, and moreover such band clouts often cause damages to the load.

The object of the present invention is to eliminate these drawbacks and to provide a load supporting pallet,

which is rigid and .can stand rough treatment without the boards therein being split,V which has no Ametallic members projecting [from the wood of the pallet and capable of catching the load or `the surface on which the pallet is placed, and which pallet also is easy to assemble and is simple and cheap as `regards the design of .the strengthening and connecting members.

According to the invention'said objects are attained thereby that a stiiening member for a lower 'layer board, which memberconsists ofa rod, pin, bolt or similar extending straightly and horizontallyy within a bore or groove in the board and having its ends adapted for engagement with the ylateral parts of "the board, is held 4together with .an upper layer board or an upper layer stringer by means :of a vertical connecting member, which encloses or is attached in any other way to the'middle of said stiiening member and which extends upwardly through a vertical bore to an yupper supporting or abutting member, preferably in the shape of a pin or a washer, yto which member said connecting member is attached, eg. by being bent over .the same.

Some embodiments of a pallet having Ireinforcing and connecting members according to invention will be more closely described hereinbelow with reference to the accompanying drawings. Fig. 1 shows a. preferred embodiment in a vertical section taken parallelly to the boards. Fig. 2 is a detail of another embodiment, shown in section taken at right angles to the boards. Fig. 3 is a vertical sectional View of still another embodiment.

The pallet shown in Figs. 1 and 2 consists of an upper board layer, upon which the moved load should be placed, a lower board layer resting on .the ground, and a number of spacer members in the shape of blocks 11 interposed therebetween. The blocks serve to make room between the board layers yfor the forks of a fork truck, by means of which .the pallet is lifted when moved. The lower board layer consists of parallel boards 13, usually three in number, which extend along the longer sides of the pallet and between them. The upper board layer consists of boards 15 extending parallelly to the lower layer boards. These boards may be -ive or seven in number,

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and there is a board located exactly above each one of the lower layer boards. Stringers '17 extend below and across the upper layer boards in order to connect them in the lateral direction. Preferably, there are three l stringers, one at each end of the pallet and one midway between the ends. Blocks 1&1 are arranged between the lower layer boards and the stringers. Ihe blocks are preferably made of wood, may be square or round in a horizontal cross section and are approximately as long and as wide as the width of ythe lower layer boards 113 or of stringersV 17, or often somewhat smaller. -Where the lower boards cross the stringers, a vertical bore =19 goes straight through the upper board, the Stringer, the block and the lower board. Located in said'bore is the member -for connecting the diierent parts of the pallet,

which member will be more closely described below.

At the bore 19 the lower board 13 is stitfened by a rigid pin 21 inserted into a bore yat right angles to the iibre direction of the wood and extending between the edge faces of the board and parallelly to the horizontal ilat sides thereof. The pin 21, which may consist of aV round iron Wire of a diameter of a quarter of an inch, has yan upset head at one end, which is driven into the wood, and is clinched or riveted over a washer at its other end. Said pin holds the boa-rd together in the width direction, stiiens the cross section against bending and also rein- .forces the board against shearing stresses. Therefore, the board is prevented from splitting when the pallet is roughly treated, or is held together with a strength merely' slightly reduced when the board has already been split,

" viz., by a fourfold action of the iron pin', said action consistingtherein that it counteracts: (l) stresses striving to pull .the right-handV board halt in Fig. 1 straight to the right in orderto split the board, (2) stresses striving to bend the right-hand part of the board upwardly or downwardly relatively to the left-hand part in order to brake .the board about its center line, (3) stresses striving yto raise or llower the right-hand part of .the board relatively to the left-hand part in order to shear off the board vertically, and (4) stresses striving to displace a part of the board in its longitudinal direction along a split separating said par-t from the rest of .the board; With regard to the said bending stresses, which often are the dominating ones, the pin is preferably given a rectangular cross section, the greater dimension being in the height direction.

The vertical connecting member consists of a thick wire 25 which is bent double and lfrom below inserted into the bore 19 with its branches extending .on different sides of the pin Z1, so ythat .the latter is embraced by .the bend of the Wire. The stiffness of the pin 21 causes, .that the forces vare `distributed over the. whole width of the board 13 and that lthe Wire 25 is held taut.

In addition to the above-mentioned stiiening and connecting members, nails, dented plates etc. may be used in .order to strengthen the pallet Ifurther, when required. Even the Stringer 17 may be held together by a pin extending between its edge faces. If said pin extends across .the vertical .bore 19, the wire 25 may .be bent over the same.

In case .the upper boards or .the stringers do not have any stilening pins, the pulling force of the wire 25 is transmitted to the upper layer by means of some other metallic supporting or abutting member, which distributes the forces over the surface of the wood material. Fig. l shows an example thereof. The upper board 15 has a bore 27 wider than the bore 19 through .the block 11 and .the stringer 17. A washer 29 is laid upon the recess thus lformed. The ends of the wire 2S are inserted through thev hole of said Washer and bent against the upper .face of the same. The washer forms an labutment member resting on the Stringer .17, and the upper layer boards are attached to the stringers lby nails, cramp irons Patented June 28, 1960- or similar. y.According to a modification, Ythe bore 27 is made ,so shallow that the recess between the two dilerent bore diameters is situated in the middle of the upper board 15.

" stilening memberY 21 for holdingtogether the.

in `thetransverse direction may be placed -a groove; in the .free `tlat sideot the'board, insteado-f going through albore therein. Fig, 2 shows an example thereof;

'Ihejlower board 13 has agroove 31 extending transof the pin 21,whicl1 may be bent in advance, project into said bores Ybut do--not reach up to the upper rface of the board-the pinbeing completely enclosed in Athe wood.

The vertical connecting member consists of a thick'wire 35 attached 'to -the midpoint ofthe pin 21 by welding .and ythe upperend of which beingriveted over a washer. Inthe vpallet shown in Fig 3 thevertical connecting member consistsof a .tube 37. The pinrZl, which reinlforces the lower layer board 13, extends through two diametrically opposite .bores in the wall of said tube close to its lower end. The upper end .of the ,tube holds the upper layer thereby, that it goes through and has its edge bent over a dented plate 39, interposed in .the joint between the upper layer ,board and .the Stringer 17. This design maltesthe interior of `the tube accessible vfrom above, whereby it is possible to insert therein a i 3. A load supporting pallet as'claimed in claim 1, in

which said vertical connecting member isa doubled wire embracing the .pin with its `bent Center part and having its ends clinched over said apertured plate.

pole pertaining ,to a yfence :or a framework of some kind support for the load.

Irclaimz Y Y Y Y l. A load supporting pallet, comprising a lower layer of parallel spaced boards, an upper layer of boards parallel Yto said lower layer boards, wooden'stringers connecting the upper'layer boards together, wooden spacer blocks interposed.betweenl the stringers and ythe lower layer boardsvr at their crossing poi-nts, avertical bore through lthe Y.bloclc'the lower layer boar-d, the Stringer andthe Vupper layer board, a horizontal 4bore through the lower layer V boar-d at right angles tothe grain of the wood of' said board and in communication with said vertical bore, a rigid pin inserted in said horizontal bore and having its ends fastened to the side portions of the board, an apertured plate located above said Stringer, anda vertical connecting member in said vertical bore, the lower end of which is connected to the middle part of said pin and 'the upperend of which is put through and clinched over .'saidplate. f Y

w 2. A load supporting pallet as claimed in claim l, in

whichY said vertical connecting member'is a tube.

4. A load supporting pallet comprising an upper layer of boards, a lower layer of boards, a plurality of spacer members inserted between said layer of boards, each spacer member having a'centra vertical .bore and each lower layer board havinga vertical bore yforming an extension of the'boreof the adjoiningrspacer'member and a horizontal bore approximately midway between and parallel tothe broadtaces of the board Yand crossing Y said vertical bore in the-interior of the board, vaV stiffening member comprising a substantially straight pin inserted in said horizontal bore, said stiffening member having ends in engagement withthe edge parts 'of 'the board, a vertical connecting member inserted in the bore of said spacer member, said vertical connecting member being made separately 'from said stiffening member and connected -to the same `at the crossing point ofthe vertical bore and the horizontal bore within the lower layer lboard, and a metallic supporting member arranged inthe upper layer board and located below the upper face thereof, said vertical connecting member being fastened to said metallic member to hold the upper and lower layer boards together.

5. A load supporting pallet as claimed in claim 4, in which said connecting member comprises a tube having two diametrically opposite apertures atan end thereof,

. said pin being connected to said tube by beinginserted through said aperture. Y

Y 6. A loadsupporting pallet a's claimed'in claim l, in which therupper layer board has a vertical bore of a greater diameter than the bore of thestringer,V and the apertured plate is shapedas va washer and rests upon the recess 4formed by said `dilerently sized bores.

iAload supporting pallet as 'claimed' in clairn l, in which said apertured 'plate isa `dente-.d plate clasped between't'he Stringer and'the"upper layer board.

References Cited in the vile'ofrtliis patent UNITED STATES .PATENTS 1,230,335 standiford. -'J1ine 1,9, 1917 1,320,753 Hubbard Nev. 4,1919 2,597,41; vankrimpen May 2o, 1952 Y' Y'FOREIGN PATENTS Y 4,336 Great Britain of 1901 147,838Y Sweden Nov. 23, 1954 709,051 Great Britain May v12, 1954 728,424 Great Britain- Apr. 20, `1-955