This invention relates to stirrups for horse riding, particularly safety stirrups which reduce the risk of a rider's foot being caught if the rider falls from the horse.

Conventional stirrups comprise an inverted U- shaped member closed by a straight foot-plate. The ball of the foot rests on the foot-plate, the U-shaped member arching over the top of the foot. The foot should not be in contact with the U-shaped member in normal riding, so different sizes of stirrup are available to ensure that the U-shaped member is clear of the foot. At the top of the U-shaped member is a slot or clip to attach the stirrup to the stirrup leather by which it is attached to the saddle.

This kind of stirrup suffers from the problem that, in some falls, the rider's foot may become angled upward and trapped between the foot-plate and the top of the stirrup. The foot-plate presses against the arch of the foot, and the U-shaped member against the top of the toes. In this situation the rider may be dragged for some distance by the horse until the foot works free. This often leads to more severe injury than would otherwise result from the fall. ^" Attempts to overcome this problem have included a breakable or frangible stirrup, which is designed to break away from the stirrup strap should a fallen rider's foot be trapped, and a two-part stirrup, as disclosed in

Australian patent application No. AU-A-62109/90 (Hayden Gregory Bostock) , which has a rather elongated arch portion within which is a boot support which fits over the top of the rider's boot. This support is formed from two curved side members, extending forwardly from the foot-plate at each side, which meet at the top of the support. There is a hinge in each member just above the foot-plate to allow them to swing outwardly apart from each other, when not in the plane of the elongate arch portion. The boot support is pivotably attached at each side to the bottom of the arch, between each hinge and the foot-plate, to allow the boot support to swing down out of the arch if the rider falls, the attached foot¬ plate pivoting about a horizontal axis to follow the rider's foot. The arch of the stirrup is long enough for the rider's toes not to come into contact with it as the foot plate pivots, so the foot does not become trapped. The boot support side members can then open to release the rider's foot. This is a complex, bulky and heavy arrangement and is expensive to produce.

Inventors Certificate SU 1560465 discloses a stirrup comprising top and bottom plates bolted to two connecting rods each having two hinges spaced along its length. Each rod is surrounded by a compression spring to keep the rods straight. This is also an unnecessarily complex assembly.

According to the present invention there is

provided a stirrup comprising an inverted U-shaped member closed by a foot-plate, said U-shaped member having at its apex means for attachment to a stirrup leather; each arm of the U-shaped member having a single joint part-way along its length to allow the lower portions of the arms and the foot-plate to pivot relative to the upper portions of the arms, the joint being situated at a distance from the foot-plate in the range 25-75% of the distance between the foot-plate and the apex of the inverted U-shaped member.

Pivoting of the lower portions of the "arms relative to the upper portions creates free space between the foot-plate and the apex of the stirrup to allow the rider's foot to be withdrawn. Use of a single joint on each side of the stirrup provides a simple structure with few moving parts which is unlikely to jam and is relatively simple to manufacture. It also allows the safety stirrup to be very similar in appearance to conventional stirrups. Preferably each joint has a single pivot axis.

The joint may be situated at a distance from the foot¬ plate in the range 40-60%, an especially preferred embodiments about 50%, of the distance between the foot¬ plate and the apex of the inverted U-shaped member. This positioning allows an optimal free space volume to be achieved when the foot-plate and lower portions of the arms pivot relative to the upper portions.

Preferably the joint is a hinge or pivot joint,

desirably allowing the foot-plate and lower portions of the U-shaped member's arms to pivot out of alignment with the upper portions in both directions. Use of a simple hinge mechanism, with few moving parts, allows a much 5 less bulky construction than previously known safety stirrups. Movement in either direction allows the safety stirrup, like a conventional stirrup, to be fitted to the stirrup leather either way round. Also, if the stirrup leather becomes twisted during riding, for example if the

10 rider's foot leaves the stirrup at any time, then the two-way action will still allow the hinge to function if the rider should fall off.

The joint may be formed to allow pivoting though an angle of 45° - 220°, preferably 45° - 100° in either

15 direction.

Generally, a safety stirrup according to the invention is of a similar size to conventional stirrups, i.e. the internal height of the U-shaped member, from the top of the foot-plate to the apex, is such as to clear

20 the tope of the rider's foot when the foot is in the stirrup. An overall height of between 7.5 and 18 cm, preferably between 10.5 and 15 cm, is suitable but different sizes of stirrup are needed to fit different riders.

2.5 In some embodiments, the pivot joint is provided with a detent to retain the upper and lower portions of the U-shaped member in alignment during normal riding. This feature also allows the arms of the stirrup to be

brought back into alignment, and held there, after that alignment has been broken in a fall so that the stirrup may be used for safe riding immediately after a fall. Means such as a spring or other resiliently deformable member may be used to bias the stirrup of the invention into the normal riding position in which the upper and lower portions of the arms of the U-shaped member are substantially aligned.

It is strongly preferred, however, that the joint of the stirrups are essentially free-swinging. The less restricted the pivoting motion i.e. the more easily the lower portion of the stirrup moves out of the plane of the upper portion, the more comfortable is the ride. This is partly because the rider may more easily adopt the recommended "heels down" riding position, and when on this position may keep his foot flat on the foot plate. Added comfort may also arise from increased ease of movement between foot positions, for example when performing so-called "flying moves" in dressage riding which involves pushing the toes forward and heels backward, alternately.

A further advantage is that the safety stirrup is less likely than a conventional stirrup to move away from the rider when forward pressure is applied during mounting and dismounting by instead pivoting forward at the joint, making mounting and dismounting easier.

Other suitable forms of joint for use in a stirrup according to the invention included ball-and-

socket joints, double ring joints and enclosed cylinder joints in which one half of the joint comprises a cylinder which is held within an enclosure formed in the other half of the joint and is rotatable about its longitudinal axis within that enclosure.

Alternatively, the joint may be in the form of a flexibly or resiliently deformable insert, for example formed by bevelling the opposed ends of the upper and lower portions of the arms of the U-shaped member and inserting an elastomeric or other deformable strip into the opposed ends, to link the portions. The bevelled ends allow pivoting of one portion relative to the other, which deforms the linking strip. When the portions are released the strip may return to its original form under gravity or, if a resilient member is used, under the influence of that member, thereby straightening the stirrup. Alternatively, deformable strips may be affixed to the opposed ends of the upper and lower portions of the arms by way of deformable sleeves integral with the strip and enclosing the free ends of the upper and lower arm portions.

Any of these types of joints may be made to be free-swinging, biased, or with a detent.

Stirrups according to the invention may be formed from any of the materials known in the manufacture of conventional stirrups. These include steel, chrome- plated steel or stainless steel, aluminium and titanium- aluminium alloys and nylon or other synthetic mouldable

materials .

In most practical embodiments all portions of the inverted U-shaped member are formed from metal or other rigid material, although all portions need not necessarily be made of the same rigid material. A further embodiment of a safety stirrup according to the invention, however, may have the apex, upper portions of the arms of the U-shaped member and the foot-plate made from metal or other substantially rigid material and the lower portions of the arms from an elastomeric or other flexible material. The joints between the rigid and flexible portions of the stirrup may, in this embodiment, be fixed or may allow the portions joined to pivot or swing relative to one another. The choice of material may be made for the properties of the materials or to simplify manufacture or reduce costs. For example, the use of die or sand cast aluminium or injection moulded plastics may be cheaper than lost-wax steel castings and may be lighter, though less strong.

The use of flexible materials or resiliently deformable joints has the added advantage of providing a cushioning effect which gives a more comfortable ride than a conventional rigid stirrup. The appearance of the safety stirrup can be made to be very similar to conventional stirrups.

The safety stirrup may be used in all forms of riding, both recreational and professional, including

horse racing. It will be of most benefit to children, the disabled and less experienced riders who may not be able to remove their feet quickly from the stirrups if they are about to fall. They will also benefit from the comfort and ease of mounting/dismounting. It will, however, also be of use to more experienced and professional riders, who will find the improved ride comfort an especial advantage if they have to spend long periods of time in the saddle. Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Fig. la is a front elevation of a safety stirrup according to the invention; Fig. lb is a side elevation of the stirrup shown in Fig. 1;

Fig. 2a is an oblique view of a second embodiment according to the invention;

Fig. 2b is an oblique view of the stirrup of Fig. 3, flexed at the pivot joints,-

Fig. 3 is a front elevation, in partial cross- section, of a third embodiment of the invention;

Fig. 4 is a side elevation of the stirrup of Fig. 3; Fig. 5 is a side elevation of the safety stirrup of Fig. 3 in use, showing the position of a fallen rider's foot.

Fig. 6 is a partial front elevation of a third

embodiment of the invention;

Fig. 7 shows cross-sections of two versions of the stirrup of Fig. 6;

Fig. 8 is a cross-section of a fourth embodiment of the invention;

Fig. 9 is a cross-section of the stirrup of Fig. 8 taken at right angles to Fig. 8; and

Fig. 10a is a further embodiment of the invention. The safety stirrups are formed from a U-shaped member 3, closed by a foot-plate 2. The U-shaped member 3 arches over the rider's foot. The foot-plate 2 may be formed with a slot to be fitted with an inset 4 to provide grip. This inset 4 may be formed of rubber or other conventional grip-providing material. (See Figs. 3 and 4) .

At the top of the stirrup 1, is a slot 14 through which a stirrup leather (not shown) may be passed to allow the stirrup 1 to be hung from a saddle. In all embodiments shown, the stirrup 1 has a joint approximately half-way down each arm of the U- shaped members. In the embodiment of Figs. 1 and 3-5 the joint is a hinge 9, provided by a projection 6 on the upper portion of the arm which is fitted into a space between two projections 8,10 on the lower portion 7 and secured by a pin 12 passing through all three projections. The arrangement of the single 6 and paired projections 8,10 may be reversed, as shown in the

embodiment of Fig. 2. In the embodiment of Figs. 3-5, the hinge joint 9 is provided with a detent in the form of a ball-bearing 16, positioned in a cavity between the projections 8,10 on the lower portion 7 of each arm of the U-shaped member. The ball-bearing 16 is pushed upwards against the projection 6 by a spring 18 or other resilient biasing means. When the upper 5 and lower 7 portions of the arms are in alignment, this ball-bearing 16 fits into a groove 20 in the upper projection 6. When the upper 5 and lower 7 portions of the arms are forced out of alignment, the ball-bearing is moved out of the groove. The detent is an optional feature; if it is not provided (Figs. 1, 2, 6-10) the joint is free to pivot at all times to permit a more comfortable ride. Figs. 2a and 2b show an embodiment of the safety stirrup 1 of the invention in aligned configuration (Fig. 3a) and "broken" configuration in which the foot-plate has been swung .out of the plane of the stirrup. This shows the operation of the hinge joint 9. Fig. 5 shows the position of the rider's foot after a fall. This position will also apply to the embodiments of Figs. 1, 2 and 6-10 without the detent. The stirrup 1 has assumed the "broken" configuration as in Fig. 2b. The ball-bearing 16 has been moved from the groove 20, by flexing of the hinge joint 9 as the projection 6 rotates about the pin 12. The ball-bearing ' 16 remains biased against the projection 6 by means of the spring 18, so that if the arms of the stirrup are

brought back into alignment it will be pushed back into the groove 20.

In the situation depicted in Fig. 5, the rider has fallen from the saddle, and the toe of his foot has swung upward and has come into contact with the apex of the U-shaped member. Because of pressure of the rider's instep against the foot-plate 2, the foot-plate 2 has followed the motion of the rider's foot, swinging out of the plane of the stirrup. This gives a free space between the foot-plate 2 and the apex of the stirrup,, so the foot can now be withdrawn downwardly, relatively easily, to free the rider and reduce the risk of serious injury.

Figs. 6-9 show embodiments having joints formed from an insert of flexible resiliently deformable material situated between the upper and lower portions 5, 7 of the arms 3. As well as giving the required pivoting joint flexbility can have a cushioning or shock-absorbing effect which improves ride comfort. In the embodiment of Figs. 6 and 7, a flexible or resiliently deformable strip 25, such as any polymer, e.g. a rubber or a synthetic elastomer, is inserted (Fig. 7) into a slot 23 in each of the opposed ends 20, 22 forming the joint. One possible method of securing the strip (Fig. 7b) is by the positioning of protrusions 26 from the strip 25 into corresponding notches in the slot ^' 23.

In the embodiment of Figs. 8 and 9, a

resiliently deformable strip 30, which again may be made for example of rubber or a synthetic elastomer, is formed integrally with two sleeves 32, 34. The sleeves are fitted over the ends 20, 22 of the upper and lower portions 5, 7 of the arms 3 to form the flexible joint. The embodiments of Figs. 6-9 work in the same way as those of Figs. 1-4, seen in Fig. 5. The spacing between, and bevelled edges of the ends 20, 22 of the arm portions 5, 7 allow the lower portions 7 of the arms 3 to swing relative to the upper portions 5, in either direction.

Fig. 10 shows a further embodiment having a different hinge, in which the upper 5 and lower 7 portions of the U-shaped members 3 arms each have a single protrusion , 80, 100. These are positioned adjacent one another and secured by a pin 12 passing through them.

As can clearly be seen from the figures, the simplicity of structure required to put the invention into practice allows the safety stirrups to resemble conventional stirrups very closely. Even racing stirrups, which must have a very light, but yet strong structure and are usually formed from much slimmer elements than stirrups for normal riding, can be made to embody the invention. This means that the safety,- comfort and convenience advantages offered by the stirrups are available to all ages and abilities of rider and in all kinds of riding.