US 2013520 A
Description (OCR text may contain errors)
Sept. 3, 1935. C. MCDERMOTT 2,013,520
APPARATUS FOR USE IN THE INSTRUCTION OF SWIMMING :5 Sheets-Sheet 1 Filed Nov. 2, 1955 www om @m @qs/wm Esme/"U27 Mik/mf l uw v c i l Sept. 3, 1935. c. MCDERMOTT APPARATUS FOR USE IN THE INSTRUCTION OF SWIMMING Filed Novf `za, 1953 5 sheets-sheet 2 Sept. 3, 1935. CF MCDERMOTT 2,013,520
APPARATUS FOR USE IN THE INSTRUCTION 0F SWIMMING Filed Nov. 2, 1935 5 Sheets-Sheet 3 55mm-'m MEW/770i? j Patented Sept. 3, 1935 UNETEB STATESI PATENT @FFEQE APPARATUS vFOR USE IN THE INSTRUC- TION OF SWIMNHNG 1 f Claim.
This invention relates to apparatus for use in the instruction of swimming, and has as an object to provide an apparatus by which the arms and legs are positively and coordinately moved as required in a particular swimming stroke.
lVLcre specifically, it is an object of this invention to provide an apparatus adapted to be set up in a gymnasium or in the home, and having a table like support on which the user lies with his legs and arms engaging movable elements adapted to positively move the arms and legs, as is necessary to perform correctly a certain style of swimming, especially the crawl, although the motions of other strokes also may be produced.
With the above and other objects in View which will appear as the description proceeds, my in vention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly dened by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.
In the accompanying drawings, I have illustrated one complete example of the physical embodiment of my invention constructed according to the best mode I have so far devised for the practical application of the principles thereof, and in which:
Figure l is a side View of the apparatus and illustrating its manner of use;
Figure 2 is a top plan View;
Figure 3 is a rear end View;
Figure 4 is a detail section view taken through Figure 1 on the plane of the line 4 4; and
Figure 5 is an enlarged fragmentary section view through one ofthe guide channels illustrating a structural detail.
Referring now more particularly to the accompanying drawings in which like numerals indicate like parts throughout the several views, the numeral 5 represents the general frame of the apparatus which is preferably formed of tubing and consists of two similar side units 6 connected together by upper and lower cross members 1 and 8, respectively.
Each side unit consists of a lower longitudinal rail 9 and a top rail IG, maintained in spaced parallel relationship by vertical members II and diagonal b-races I2.
The various members are connected together by suitable fittings to which they are preferably welded and certain of the lower ttings are provided with feet I3, upon which the entire apparatus rests. It is observed that the vertical members I I havetheir medial portions'bent'outwardly to add to the space within the frame.
Extending across the lower side rails 3 are shelves I5, I6 and 'I'I. Mounted on the cross shelves I5 and I5, respectively, are pedestals I8 and i9 which support a table indicated generally by the numeral 20. The table 2li comprises a stationary rear section 2l and a rocking forward section 22. The forward section 22 is mounted on a longitudinal supporting shaft 23, having its ends anchored to the upper ends of the pedestals I8 and I9.
The sections of the table are so proportioned that the rear fixed section 2'I supports substantially the hips of the user, while the forward rocking section 22, supports the chest and shoulders. It is observed that the front end 0f the rocking section 22 is inclined upwardly soas. to insure arching of the back. The manner in which the rocking of the forward section. is effected will be hereinafter described.
Hingedly attached tothe rearl edge of the xed table section 2i are two leg. supports 24 of a length to extend substantially to the ankles. Spring clasps 25 at their outer'free ends of these supports engage and hold the ankles.
The leg supports 24 are supportedand are simultaneously and oppositely reciprocated up and down by connecting rods 26attached at their upper ends to the leg supports 24 as at 2l and connected at their lower ends to eccentrics28. The eccentrics 28 are iixed toa cross shaft. 29 journalled in bearings 30 restingV on the rear portion of the shelf I5.
Mounted on the inner face ofeachzside unit 6 is a substantially elliptical channel track 3l. As best illustrated in' Figure 5, .the channel tracks have their open inner sides partially closed. by plates 32, the space left being sufiicient to accommodate extensions 33, projecting inwardly from the tracks and carried by endless sprocket chains 34 dispo-sed therein.
The extensions 33 of the two chains are diametrically opposite, and attached to their outer ends are flexible connections 35 provided with loops at their outer free ends to receive the hands or wrists of the user.
The sprocket chains are driven about the channel tracks in a clockwise direction with respect to Figure 1, by drive sprockets 36 located at the forward end of the apparatus. Obviously, where the drive sprockets 36 mesh with the sprocket chains, the outer walls of the channel tracks are cut away to permit the sprocket wheels to enter and mesh with the chains.
The sprockets 36 are fixed to a cross shaft 31, journalled in bearings 38 mounted on the shelf I1 and driven from a motor 39 mounted on an extension of the shelf Il, through a belt drive 40. Inasmuch as both chains are driven from the single drive shaft 31, it follows that they are at all times in step with their hand engaging elements at all times opposite each other.
It is observed that the drive shaft 31 also drives a longitudinal shaft 4I through a bevel gear connectlon 42. The longitudinal shaft 4I has its rear end journalled in a bearing carried by the pedestal I9 and its forward end journalled in a bearing 43 mounted on the shelf Il.
Adjacent the pedestal I9, the shaft 4| has a pinion 44, which meshes with a gear 45 xed to a stub shaft 46 journalled in a bearing also carried by the pedestal I9. 'Ihe opposite end of the stub shaft has a small crank disc or eccentric driver 41 xed thereto which is connected through a rod 48, with the rocking forward table section 22. The gear ratios of the pinion and gear 44 and 45 respectively, and the bevel gear connection 42, are such that the rocking of the table section 22 is properly coordinated with the motion of the chains, which carry the arms of the user through their required movements.
At the rear end of the apparatus, there are two power take-off sprockets 49, meshing with the sprocket chains. These sprockets are fixed to a cross shaft 59, journalled in bearings carried by levers 5l pivotally mounted on the shaft 29 adjacent its bearing supports 35. The shaft 59 also has a pinion 52 xed thereto, which meshes with a gear 53 xed to the shaft 29, so that the shaft 29 is driven from the chains through the power take-off sprockets.
The levers 5l have extended end portions 54 provided with arcuate slots 55 concentric to the axis of the shaft 29. Locking screws 55 threaded in extensions of the bearing supports 3) and having their heads engaged in the enlarged end portions of the arcuate slots 55, serve to hold the levers 5l in either of two positions of adjustment.
Through this adjustability of the levers 5| which carry the shaft 59, it is possible to alter the ratio between the speed of the sprocket chains and the cross shaft 29, which actuates the leg supports. In the embodiment illustrated, the ratio is such that a six beat crawl stroke is produced.
Substituting power take-off sprockets of smaller diameter for the sprockets 49 and adjusting the levers 5I, accordingly, permits the ratio to be quickly changed to produce an eight beat stroke. Other ratios of the leg movements to the arm movements are possible with similar alterations.
Operation' As stated, the present embodiment is arranged for the instruction of the six beat crawl. In this stroke, there are six leg beats, three with each leg, to one complete cycle of arm movements. Also, for each cycle of arm movements, the upper part of the body rolls to one side, preferably the right, to permit taking in a breath of air. These movements are all positively coordinated in the present apparatus.
The manner of use is clearly illustrated in Figure 1. As here shown, the user lies on his stomach, engages the ankles with the spring clasps 25, and inserts his hands through the loops of the flexible connections 35. The motor is then started by an attendant, and the various movements take place.
It is, of course, obvious that the exact motion of the arms is not obtained through the functioning of the apparatus, but coordination of the arm and leg movements with the body roll are obtained, and this is the most diflicult part of learning this particular stroke.
From the foregoing description, taken in connection with the accompanying drawings, it will be apparent to those skilled in the art that this invention provides novel means Vfor facilitating the instruction of different strokes in swimming and while the embodiment illustrated shows its adaptation particularly to that style of swimming known as the crawl, it is readily apparent that the apparatus may be easily adapted for the instruction of the other styles of swimming especially the back stroke, without deviating from the spirit of the invention.
What I claim as my invention is:
In an apparatus for the instruction of swimming, a substantially horizontal body support composed of a stationary portion and a rockable portion, means to mount Said body support including spaced pedestals one of which supports the xed portion of the body support directly, means to rock the body support comprising a crank rotatably mounted from the other pedestal, a rod connecting the crank and the body support, leg supports hinged to the xed portion of the body support, crank means to reciprocate said leg supports, substantially elliptical guide tracks at opposite sides of the body support, means travelling about said guide tracks to carry the arms along defined paths, and drive means to simultaneously actuate the cranks driving the rocking body support and the leg supports and to cause said arm carrying means to travel about the guide tracks.