US2394477A

US2394477A - Laminated wood wheel and method of making same

Info

Publication number: US2394477A
Application number: US461828A
Authority: US
Inventors: David M Pope; Thomas F Spackman
Original assignee: Stewart Warner Corp
Current assignee: Stewart Warner Corp
Priority date: 1942-10-12
Filing date: 1942-10-12
Publication date: 1946-02-05
Anticipated expiration: 1963-02-05

Description

Feb. 5 1946. D. M. POPE ETAL.

, LAMINATED WOOD WHEEL AND METHOD OF MAKING SAME Filed Oct. 12, 1942 dies and the entire wheel pressed together under a hydraulic pressure of 500 pounds to the square inch and at a temperature of 300 F. These dies have recessed or concave faces and produce the completed assembly shown in Fig. 2, exceptthat the assembly at this'stage lacks therivets 36.

The wheel is then bored through a spot mark placed on the side plates at the time they were molded, the bit passing through the two side plates and center core to form the axle beari'ng 32, clearly shown in Figs. 1 and 2 of the draw- It is to beunderstood that the particular wheel I be painted, lacquered, varnished'or finished in any other suitable manner immediately after the entire assembly has been removed from the final hot pressing operation. Where rivets are added tonthe. wheel, such finishing operation would orplaced in the wheel.

dinarily beperformedafter the "rivets had been selected for purposes of illustration is merely one of many possible embodiments of our invention and that the particular pressures, temperatures,

ing. The wheel is then placed on a centering pin 7 and turned slowly against high 'speedcutting knive which give the final finish to the wheel and make it perfectly round in relation to its axle thicknesses of wood, number of laminations, number of segments and type of bonding material usedmay be varied without departing from the scope of our invention. The kinds of woods spe The wheel resulting from the foregoing steps is V 7 complete and entirely satisfactory for most uses. The urea resin forms a permanent waterproof bond which is stronger than the wood itself. .This bond is slightly resilient and will not shatter under a blow and this resiliency permits the bond to give with the, wood and retain a firm grip on the wood under all stresses and strains to which the wheel is subjected.

Our novel wheel has several advantages to which we wish to call particular attention; The rim is homogeneous and continuou and is not weakened by the pressure of spoke sockets or other interruptions to its continuity. The grain of'the wood is arranged substantially radially of the rim and when this rim is subjected to. con-' siderable wear or strikes objects which would ordinarily splinter wood in its natural state, the end grains of the fibre tend to'mushroom out and to remain attached to the rim. The more the rim is abused, the softer the outer part of the rim becomes without in any appreciable way losing its roundness or ability to withstand indefinitely further shocks and wear.

The side plates form strong and continuous but light supports connecting the rim with the axle core. The curvature of these side plates permits the use of arelatively long axle core with a mar-.

row rim and provides a wide axle bearing without appreciable increase in weight. This curvature also increases the lateral strength of the side plates and of the entire wheel. tween the rim and the'core reduces weight and eliminates wood where additional strength is not needed. Our novel design fully'develops the tensile strength of the Wood and leaves the wheel,

separate operation, as desired. Washers 38 "are preferably interposed between the enlarged ends of the rivets and the side plates to prevent the ends of the rivets from cutting into the side:

plates. While the wheel would stand up without these rivets inordinary usage, the rivets give a double guarantee against: any possible splitting of th'ewood and once these rivets arein placethe entire assembly is tied together, irrespective .of any individual failure of the resin bond or split: ting of any individual piece of wood.

Where the wheclis used withoutrivets, it may The space be- 5 core, subjecting the assembly thus formed to stituting merely typical examples of various k nds of wood suitable for our purpose and the urea resin'referred to is merely a typical example of'a bonding material belonging to a group of thermo-setting plastics. Our invention is to be construed as including all variations and modificationsfalling within the scope of the appended claims. r

We claim:

1. That method of constructing a laminated Wood wheel which comprises cutting out a plurality of equal arcuate wooden segments, arranging said segments to form a plurality of rings, securing together the segments forming 'each ring, superimposing the several rings with urea resin therebetween'and with the joints ber 7 tween the segmentsof each ring offset from the joints between the segments of all the other rings, subjecting the stack of rings thus formed topressure and heat to mold said rings into a permanent rim, cutting out a plurality of circular, fiat blanks ,of wood, placing a plurality} of said blanks upon each other with urea'resin therebetween, subjecting said blanks to pressure and heat'andsimu'ltaneously ofisetting the central portion of said blanks to form a permanent molded side plate, forming an axle core of wood, assembling said core and mm in spaced relation between a pair of said side plates and with urea resin between said side plates and the contacting surfaces of said rim and core, subjecting 2. That method of constructing a laminated wood wheel which cor'np'rises cutting out a plus rality of equal arcuate wooden segments; ar

ranging said segments to form aplurality of rings,

securing together the segments forming each ring,

superimposing the several. rings with thermosettir'ig'resin therebetween and with the joints between the segments :of each ring ofiset from the joints between the segments of all the other .rings, subjectingthe. stack of rings thus formed to pressure and 'heat to mold saidrings into a permanent rim, cutting out a plurality of circula'r, fiatblanks off-wood, placing a plurality of saidblanks "upon each other with thermo-setting. resin therebetween, subjecting said blanks to pressure and heat and'simultaneously oiiset ting the central portion'of said blanksto form a permanent molded side'plate, forming anaxle core of wood, assembling said core and rim. in spaced relation between a pair of said side plates and with thermo-setting resin betweensaid side plates and the contacting Surfaces of said rim and heat and pressure to set said thermo-setting resin andthereby form a permanently bonded wheel, and forming a bearing in said side plates and core.

3. That'method of constructing a laminated wood wheel which comprises cutting out a plurality of equal arcuate wooden segments, arranging said segments to form a plurality of rings securing together the segments forming each ring, superimposing the several rings with urea resin therebetween and with the joints between the segments of each ring offset from the joints between the segments of all the other rings, subjecting the stack of rings thus formed to pressure and heat to mold said rings into a permanent rim, cutting out a plurality of circular, flat blanks of wood, placing a plurality of said blanks upon each other with urea resin therebetween, subjecting said blanks to pressure and heat and simultaneously ofisetting the central portion of said blanks to form a permanent molded side plate, forming an axle core of wood, assembling said core and rim in spaced relation between a pair of side plates and with urea resin between said side plates and the contacting surfaces of said rim and core, and subjecting the assembly thus formed to heat and pressure to set said urea resin and thereby form a permanently bonded Wheel.

4'. That method of constructing a laminated wood wheel which comprises cutting out a plurality of equal arcuate wooden segments, arranging said segments to form a plurality of rings securing together the segments forming each ring, superimposing the several rings with urea resin therebetween, subjecting the stack of rings thus formed to pressure and heat to mold said rings into a permanent rim, cutting out a plurality of circular, flat blanks of wood, placing a plurality iii of said blanks upon each other with urea resin therebetween, subjecting said blanks to pressure and heat to form a permanent molded side plate, forming an axle core of wood, assembling said core and rim in spaced relation between a pair of said side plates and with urea resin between said side plates and the contacting surfaces of said rim and core, subjecting the assembly thus formed to heat and pressure to set said urea resin and thereby form a permanently bonded wheel, forming a bearing in said side plates and core, and inserting reinforcing rivets through said plates and rim.

5. That method of constructing a laminated wood wheel which comprises cutting out a plurality of equal arcuate wooden segments, ar ranging said segments to form a plurality of rings securing together the segments forming each ring, superimposing the several rings with urea resin therebetween and with the joints between the segments of each ring offset from the joints between the segments of all the other rings, subjecting the stack of rings thus formed to pressure and heat to mold said rings into a permanent rim, cutting out a plurality of circular, fiat blanks of wood, placing a plurality of said blanks upon each other with urea resin therebetween, subjecting said blanks to pressure and heat and simultaneously offsetting the central portion of said blanks to form a permanent molded side plate, assembling said rim between a pair of said side plates and with urea resin between said side plates and the contacting surfaces of said rim, and subjecting the assembly thus formed to heat and pressure to set said urea resin and thereby form a permanently bonded wheel.

DAVID M. POPE. THOMAS F. SPACKMAN.