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Publication numberUS809980 A
Publication typeGrant
Publication date16 Jan 1906
Filing date25 Oct 1905
Priority date25 Oct 1905
Publication numberUS 809980 A, US 809980A, US-A-809980, US809980 A, US809980A
InventorsEdvard Petrini
Original AssigneeEdvard Petrini
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 809980 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

No. 809,980. PATENTED'JAN. 16, 1906. E. PETRINI.



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Specification of Letters Patent.

Patented Jan. 16, 1906.

Application filed October 25, 1905. Serial No. 284,388.

To all whom it may concern.-

Be it known that I, EDVARD PETRINI, a subject of the King of Sweden, and a resident of Uppsala, in the Kingdom of Sweden, have invented certain new and useful Improvements in Roller-Skates, of which the following is a full, clear, and exact description.

The object of the invention is to provide a roller-skate with means whereby power may be applied to rotate one of the wheels of each skate to carry the skate forward, the power being derived from the weight of the skater and rendered effective by the alternate lifting of one foot and the transferring of the weight of the body to the other.

The invention comprises the construction and arrangement of parts hereinafter described, and particularly pointed out in the claims.

It is illustrated in the accompanying drawings, in which Figure 1 is a perspective view showing the parts in position assumed when the weight is resting on the skate. Fig. 2 is an elevation of the opposite side from that seen in Fig. 1 in position assumed when weight is removed. Fig. 3 is a detail plan view of one of the wheels, and Fig. 4 is a detail view.

Referring by reference characters to the drawings, it will be seen that I provide a frame comprising two elements A and B, pivotally connected together. The front ele-v ment is composed of two angular-shaped bars a and a arranged parallel to each other and rigidly connected together by cross rods or members, as will hereinafter more fully ap- The other element B is likewise composed of two rigidly-connected bars of similar shape. These two elements, which I may conveniently designate as arms, are pivotally connected at the angle or bend by a cross-rod (Z. Between the lower extremities of the members of the element or arm A is journaled the driving-wheel e, to which the power is applied. The lower extremities of the members of the element or arm B are provided with lugs or brackets 7c, which are connected by a tubular rod k. This carries a bearing-bracket i, to which is pivoted a head it of carrying-arms f, between which the rear wheel f is j ournaled. The pivotal connection is effected by providing lugs Z on the head it, overlapping the bracket i at top and bottom and passing a hinge-pin through alining openings in said parts.

The free angular ends or portions of the arms or elements A and B are turned in opposite directions and are connected by the rods g and g from which is suspended a foot rest or support adapted to receive and hold the foot in the position shown in Fig. 2 in dotted lines. This foot-rest c is composed of side frames 0*, suspended at the rear from the rod g and at the front from the rod 9 by links a n connecting at their lower ends to the cross-rod M, which supports the soleplate. Straps m. and a heel-spring m are provided for holding the foot in place.

WVith the parts in the position shown in Fig. 2 it will be readily seen that when the weight of the skater is thrown on the foot rest the downward pull tln'ough the uprights upon the ends of the elements or arms A and w B will tend to spread the lower or wheel-carrying ends apart. This spreading of the arms I use to impart rotary motion to the drive-wheel e through the mechanism which will now be described.

A drive-drum (preferably with sprocketteeth) 5 is connected to the hub of the drivewheel by a suitable clutch, (not shown,) so that the wheel 6 will be rotated forwardly when the drive-drum s is rotated in this direction, but is free torotate forwardly independent of the drive-drum if the latter is stopped or reversed. A chain t, having its front end secured to this drum, is carried back and secured to a drum 25, fast on a shaft t journaled in the tubular connecting-rod 7c. The shaft t carries at its opposite end a similar drum or wheel u, to which is secured one end of a chain a, the opposite end of which is secured to one of the forks in which wheel e is journaled. Thus as the elements or arms A and B are spread apart the pull upon chain a will cause it to unwind from drum a, rotating the latter and shaft t and drum t. This will tend to wind up chain t on drum t, and as the chain-wheel t is being carried bodily to the rear by the separation of the arms a double pull or speed will be imparted to chain t, which will be unwound from drum or wheel 8 at a corresponding speed, and by reason of the clutch mechanism before referred to wheel e will be driven and the skaters foot carried forward. In order that the arms may be drawn together again when the weight of the operator is removed, I provide the following mechanism: A sprocket-wheel s is rigidly connected to the wheel 8 and a similar sprocket-wheel is fixed on a shaft 8*, journaled in the tubular member 1", which connects the members a and a A spring (not shown) encircles the shaft in a space between it and the tubular member and has one end connected to the shaft and the other to a stationary part. An endless sprocketchain 8 passes around wheels 8 and 8 Thus as the arms are separated shaft s will be rotated to wind up the spring, and when the weight of the skater is removed the spring will through wheels 8 and s and chain s rotate drum .9 and through the chain and drum connections above described wind up the drums and draw the arms together. The downward or separating movement is limited by a cross-bar w, extending between the members a and a and in the path of the free ends of members I) and 6 It is desirable that means be provided for locking the treadle in a depressed position. This may be accomplished by a hook p adapted to engage a pin (not shown) on the inside of the member W. In order that this hook may be operated automatically, I provide the construction shown more in detail in Fig. 4. In this it will be seen that the hook is pivotally connected by a pin 19 to one arm of a bell-crank lever pivoted at p to the side frame of the treadle. The shank of the hook has an inclined end cooperating with a corresponding incline on the bell-crank lever and is normally held in the position shown in Fig. 4 by a spring 10 The arm 0 of the bellcrank lever is connected by a rod 0 with an arm 0, secured to shaft 0 which is designed to be rocked by raising the toe and depressing the heel, thus raising the front end of the treadle in its frame and rocking the shaft, or by backward pressure of the ankle or calf against an arm carried by the shaft 0 the same result may be secured.

An ordinary brake device may be provided, as indicated at o.

It will be readily understood from the foregoing description that the mere raising and lowering of the feet, as in the act of walking, or, in fact, the alternate shifting of the weight from onefoot to the other, will propel the skater steadily forward. If it is desired to turn either to the right or to the left, this may be accomplished by a simple inclination of the ankles, which, owing to the manner in which the rear wheel is mounted, will cause it to be deflected and to turn the skater in a direction opposite to that toward which the ankles are inclined.

Having thus described my invention, what I claim is 1. In a device of the character described, a pair of crossed arms pivotally connected toed on the lower ends of arms and suspended from the upper ends of the arms, and means whereby the separation of the lower ends of the arms imparts rotary motion to one of the wheels, substantially as described.

2. In a device of the character described, a

pair of crossed arms pivotally connected together and each consisting of two members, cross-rods connecting said members, wheels carried at the lower ends of said arms, a footpiece or treadle suspended from the crossrods, and driving connections to one of the wheels operated by the spreading of the arms, substantially as described.

3. In a device of the character described, a pair of pivoted arms, a foot-piece supported by said arms, a driving-wheel carried at the lower end of one arm, driving connections to said wheel operated by the spreading of the arms and a steering-wheel pivotally carried by the other arm, substantially as described.

4. In a device of the class described, a pair of arms pivotally connected together, wheels at the lower ends of said arms, driving connections to one of said wheels for rotating it when the arms are separated, means for nor mally keeping said arms pressed toward each other, a footpiece carried by said arms adapted to receive the pressure of the foot to separate said arms, and locking means for holding said foot-piece depressed and the arms separated, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.



Cooperative ClassificationA63C17/12