Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS445726 A
Publication typeGrant
Publication dateFeb 3, 1891
Filing dateSep 20, 1889
Publication numberUS 445726 A, US 445726A, US-A-445726, US445726 A, US445726A
InventorsWilliam L. Coop
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 445726 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

(No Model.)



No. 445,726. v Patented Feb. 3,1891.




SPECIFICATION forming part of Letters Patent No. 445,726, dated February 3, 1891.

Application filed September 20, 1889. Serial No. 324,517. No model.)

To all whom it may concern:

Be it known that I, TILLIAM L. COOP, of the city and county of Providence, and State of Rhode Island, have invented a new and useful Improvement in Exercising Apparatus, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification.

This invention has reference to adevice for causing resistance in an exercising apparatus to the force exerted; and it consists in the peculiar and novel construction of a piston moving in a cylinder containing any suitable liquid, byways for the passage of the liquid, means for regulating the discharge through the byways, and a check-valve or valves facilitating the return of the piston, as will be more fully set forth hereinafter.

The object of the invention is to producea resistance to the force exerted in an exercising-machine differing from a spring or a weight resistance, in that the resistance increases with the speed at a greater ratio and in readily adjusting to the force exerted.

Figure 1 is a view of an oar or sweep secured to the shaft of an oscillating piston. Fig. 2 is a horizontal section of the cylinder and oscillating piston. Fig. 3 is a vertical section of thesame on a line X X in Fig. 2. Fig. a is a vertical section of the central shaft in the resistance-box. Fig. 5 is a horizontal section of the same on the line Y Y.

Similar letters of reference indicate corresponding parts throughout.

The invent-ion is shown in the drawings in the form of an oscillating piston provided with the check-valves and adjustable byways as applied to a rowing-machine in which the fluid resistance acts similar to the water on the blade of the car.

I do not wish to confine myself to the exactconstruction shown, as it is evident that areciprocating piston may be used in place of the oscillating piston.

A in Fig. 1 is what I term a resistancebox, consisting of a short cylinder in which two valves oscillate, and in this case is pivoted at one side, so that its weight acts to balance the oar B. The stand supporting the pivotal bearing is formed into a bowl D to catch any of the resisting-fluid that may leak out. For rowing-exercises any form of slide may be used in connection with this device. Oar B is attached to shaft 0, which passes through the resistancebox A to a bearing a at its bottom, and is provided with one or more wings or pistons c, which oscillate in the cylinder of the resistance-box A and are fitted closely at their peripherv to the interior of the same. The pistons c are provided with valves 0 which permit the easy passage of a resisting-fluid when moving in one direction and close to prevent the passage of said fluid when moving in the reverse direction. The chamber E may be attached to the upper side of the resistance-box A for convenience in filling the same and to insure its being completely filled with resisting-fluid. As illustrated in the drawings, the resistance-box A is circular, being turned out inside and provided with dividing-partitions that extend from the inner circumference of the box to the central shaft 0, thus dividing the box in two parts. Passing through the shaft 0 are openings 0 which are controlled by a valve 0 to govern the flow of the resisting-fluid, as will be hereinafter more fully described.

In operation the resistance=box A is completely filled with resisting-fluid, which may be any liquid possessing lubricating qualities, and which acts as follows: As the shaft is rotated, as indicated by the arrows in Figs. 2 and 5, the valves 0 close, and the fluid,having no other means of escape, is forced through the opening 0 and passes round to the opposite side of the piston, the rapidity of its passage being governed by valve 0 at the operators will. hen a stroke is completed, the rotation of the shaft is reversed, valve 0 opens and allows an easy passage of the resistingfluid until the return-stroke is completed, when the valves close and the resisting-fluid is again forced through the openings It is evident that each side of the resistingbox A may act independently of the other side. Hence there might be only one semicircularshaped resistance-box, which would still act on the same principle and not depart fro the spirit of my invention.

Any common form of packing maybe used to prevent the escape of the resisting-fluid round the shaft 0 where it passes out at the top of the resistance-box.

Having thus described my invent-ion, I elaiin 'as new and desire to secure by Letters Patent I 1. A device for resisting the force exerted in a rowing-machine, consisting of a cylinder divided by a partition into two sections, an ear or handle secured to a central shaft provided with two pistons, and adjustable by- Ways, as'described.

2. A device for resisting the force exerted in an exercising-machine, consisting of an oar or handle secured to the shaft of an oscillating piston provided with an opening closed automatically when the piston moves in one direction and opening automatically when moving in the opposite direction, a cas- 'ing in which the piston oscillates, closely fitting the sides of the piston, and byways, as described.

3. A hydraulic device for resisting the force exerted in a rowing-machine, pivotally supported outside its center of gravity to counterbalance or partly counterbalance the oar or handle B.

4:. The combination, with the support D, of the box A, pi votally secured, the shaft 0, the passages 0 screw 0*, and openings 0 and the car B, as described.

In Witness whereof I have hereunto set my hand.

WM. L. COOP. Witnesses:

M. F. B-L-IGH,

J. A. MILLER, J r.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2725231 *Jun 1, 1953Nov 29, 1955John L PowersRowing machine
US3266801 *Oct 26, 1964Aug 16, 1966Bio Dynamics IncFluid operated rowing machine
US3377064 *Jul 15, 1964Apr 9, 1968Chester B. Skates Jr.Football trainer
US3495824 *Dec 19, 1966Feb 17, 1970Henri Alexandre CuinierFluid resistant type exercising device
US4444390 *Sep 7, 1982Apr 24, 1984Erickson David THydraulic exercising device
US4846460 *May 13, 1987Jul 11, 1989Duke John HRowing machine
US5190511 *Sep 3, 1991Mar 2, 1993Petree Larry GExercise equipment employing fluid resistance suitable for use in spacecraft and other low gravity environments
US7682296Mar 23, 2010Brown & Company Of Pensacola, Inc.Aero hydraulic exercise and physical therapy equipment and method
US7780583Aug 24, 2010Brown & Company Of Pensacola, Inc.Aero hydraulic exercise and physical therapy equipment and method
US7833136Jan 12, 2008Nov 16, 2010Bell Edward JRowing trainer
US20090181832 *Jul 16, 2009Bell Edward JRowing trainer
EP1138351A2 *Mar 26, 2001Oct 4, 2001Leslie PapeExcercise device
WO1988008735A1 *May 12, 1988Nov 17, 1988John Hincks DukeImproved rowing machine
WO1993004739A1 *Aug 11, 1992Mar 18, 1993Larry Gene PetreeExercise equipment employing fluid resistance