US 3741540 A
A nether limbs training implement having footboards having formed on its surface a plurality of protuberances, the footboard being jointed to a base block so that the footboard is swingable upwards. Springs are disposed between the footboard and base block to provide a force acting to push up one side of each of the footboards. One footboard has a spring mounted underneath that forces a steel ball into grooves on the shaft supporting the footboards.
Description (OCR text may contain errors)
United States Patent 1191 Shintizu June 26, 1973  NETHER LIMBS TRAINING IMPLEMENT 3,297,320 1/1967 Benedetto 272/57 D  Inventor: Yasuhiro Shimizu, No. 1072 Shimolshihara, ChOflI-Shi, Tokyo, 2,760,774 8/1956 Perez 272/83 R x Japan  Filed: Jan. 3, 1972 Primary Examiner-Richard C. Pinkham Assistant Examiner-Willaim R. Browne ] Appl' 214558 Att0rneyEliot S. Gerber  Foreign Application Priority Data I  ABSTRACT Oct. 25, 1971 Japan ..46/98l03 Oct. 25, 1971 Japan ..46/98l02 A "ether "ammg Implement havmg having formed on its surface a plurality of protuber- 52 us. c1. 2.72/83 R, 272/83 A mes, the being jointed to a base block so 51 Int. Cl A63b 23/04 that the fodthoard is swihgahle "P springs are  Field of Search 272/83 R, 82, 68, disposed between the foothohrd and base hlhck to P I I 27'2/67, 124/4 vide a force acting to push up one side of each of the Y footboards. One footboard has a spring mounted un-  References Cited derneath that forces a steel ball into grooves on the UNITED STATES PATENTS shaft supporting the footboards. 3,295,847
1/1967 Matt 272/83 R l Claim, 7 Drawing Figures H PATENIEnwnzs ma INVENTOR.
V/ M m w 5/.A my H. U L vrmfl NETIIER LIMBS TRAINING IMPLEMENT DETAILED DESCRIPTION OF THE INVENTION However, for many persons, it is very difficult to find the opportunity to take such a long-distance walk or run every day. Rope skipping or the use of a bicycle pedal-chain type implement is also effective for hardening the legs. But the former requires a relatively wide space for use of it, while the latter is expensive.
The primary object of the present invention is to provide a nether limbs training implement which can be conveniently used in homes and which is also relatively inexpensive to manufacture.
. The other objects and features of the present invention will become apparent from the following description of some preferred'embodiments of the invention taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a general perspective view of a nether limbs training implement embodying the present invention;
FIG. 2 is a side sectional view of the implement of FIG. 1, showing a manner of use of the device;
FIGS. 3 and 4 are persepctive views of the implements of FIG. 1 with different forms of toe holding means; i
FIGS. 5 and 6 are perspective views showing other embodiments of the present invention, with parts broken away in FIG. 6i and FIG. 7 is a front view of a compound type nether limbs training implement according to the present invention.
The nether limbs training implement of the present invention comprises essentially a flat base block 1, a footboard 2 formed with a plurality of protuberances 3 on the surface thereof, joining metal fittings 4 for pivotally securing said footboard 2 to said base block 1, and spring means 5 adapted to act so as to push up said footboard 3 relative to said base block.
Base block 1 may be of a flat plate-like configuration as shown in FIGS. 1 to 5, or may be a frame-like structure as shown in FIG. 6.0n the upper surface of said base block 1 are provided buffer elements 8 made of rubber or the like adapted to keep footboard 2 from directly hitting against base block 1.
The protuberances 3 on the top surface of footboard 2 are designed to provide a slip preventative for the sole of the user's foot placed thereon and to give a stimulus to the foot sole to promote its blood circulation. It is preferred to raise the protuberances of the portion corresponding to the plantar arch in the foot sole as best shown in FIG. 2. These protuberances 3 may be pieces shaped from relatively soft synthetic resin or other like material separately from footboard 2, said pieces being bonded to the surface of footboard 2. It is also possible to form such protuberances by engraving footboard 2 itself.
Joining fittings 4 may be provided at the end junction between base block I and footboard 2 as shown in FIGS. 1 to 4 to allow said footboard 2 to make an upand-down swining motion like a hinge, or otherwise they may be provided at the middle portions of both base block I and footboard 2 as shown in FIGS. 5 and 6 so as to make said footboard 2 movable up and down in the manner of a seesaw.
Spring means 5 may be suitably selected from coiled compression springs, coiled torsion springs, leaf springs and volute springs.
If need be, there may be provided on footboard 2 a suitable toe holding means such as covering 6 as shown in FIG. 3 or a thong 7 as shown in FIG. 4.
Now, the operation of the present implement is described. The user puts his foot on footboard 2 such that the toe portion of his foot is positioned on the pivoted side of the footboard and the heel portion on the free end side as shown by chain line in FIG. 2. With this foot positioning completed, the user makes a stepping motion by applying his body weight to the toe portion and to the heel portion alternately, whereby the open end side of footboard 2 will be brought into a closed condition relative to base block 1 when the body weight of the user is loaded on said end side, and when the load is transferred toward the toe portion; that is, when the user stands on tiptoe, said footboard 2 is swung up about the pivoted end by the stretching action of spring means 5. In this manner, said footbard 2 is allowed to make repetitive up and down motions. These forcible repetitive up and down motions of footboard 2 compel the users ankle to exercise repetitive bending and stretching motions. Such repetitive bending and stretching motions go a long way to harden various nether limb muscles such as Achilles tendon, side abdominal muscles, femoral quadriceps, femoral biceps, etc. Also, such foot motion causes corresponding movements of the upper half of the body, with such motion propagating from the backbone to the shoulder and then to the neck portion, and thus virtually the entire body of the user is caused to make swinging motion. Further, a plurality of protuberances 3 provided on footboard 2 serve to prevent skidding of the users foot sole and also give moderate stimulus thereto to promote blood circulation.
Described in the above is a nether limbs training implernent of a simple structure designed for use for one foot, but it is also possible to make a complex structure where the users both feet are subjected to training exercise. FIG. 7 shows an example of such complex structure where an elongated stem-like bar 9 formed with several circumferential click grooves 10 is journalled in joint fittings 4, and a steel ball 12 adapted to fit in one of said grooves is provided so that it is elastically pressed by a spring 11 positioned in a spring housing element 13 provided on the underside of footboard 2. Now, if footboard 2 is pushed laterally along the lengthwise direction of said bar 9, steel ball 12 is forced to ride over the click groove 10, in which it has been fitted, against the force of spring 11 and falls into the adjoining click groove. In this manner, the distance between the adjoining footboards 2,2 can be adjusted in a step-by-step manner according to the desirable distance of the user's foot.
l. A nether limbs training implement comprising a base block, a first footboard provided with a plurality of protuberances on the surface thereof, a joining metal fitting which pivotally joins said first footboard to said board, an elongated stem-like bar formed with several circumferential grooves which is journalled in one of said joint fittings of said respective footboards, a spring housing element positioned on the underside of one of said footboards, a spring disposed in said spring housing, and a steel ball fittable in one of said grooves and pressed by said spring.