Double-acting single-web swimming apparatus

An apparatus for the self-propulsion of swimmers of the type comprising an anti-drift member, a harness set connected to the said anti-drift member and adapted to be passed round the body of the said swimmer, and at least one propelling fishtail member connected to the said anti-drift member through a transmission system so mounted as to perform a swinging or oscillating motion with respect to the said anti-drift member and actuated by the swimmer, wherein the said transmission system comprises a first pivot-bar substantially parallel to the main medial plane of the said anti-drift member, wherein said propelling member is arranged to substantially freely pivot about the said first pivot bar lengthwise of the latter, wherein stop means are secured to the transmission system and arranged on the pivoting path of the said propelling member about the said first pivot bar in order to oppose its rotation preferably beyond a predetermined neutral sector or angular region, wherein the rear portion of the said propelling member beyond the said first pivot bar has a surface greater than its front portion, wherein the said transmission system comprises a rigid, substantially rectangular frame, one of the sides of which is constituted by the said first pivot bar, the frame side opposite to the said first pivot bar constituting a second pivot bar about which the said frame pivots with respect to said anti-drift member, wherein the said second pivot bar is arranged in the medial main plane of the said anti-drift member and is pivotally connected to the latter through the medium of two substantially spherical joint-balls incorporated in the thickness of the said anti-drift member, wherein two operating levers forming pedals are mounted between the said two joint balls on either side, respectively, of the said anti-drift member, and wherein each said operating lever is constituted by two arms extending on one and the same side of the said anti-drift member from the said joint balls, respectively, a curved stirrup cross-member being pivotally mounted between the ends of the said two arms.

An apparatus for the self-propulsion of swimmers of the type comprising an anti-drift member, a harness set connected to the said anti-drift member and adapted to be passed round the body of the said swimmer, and at least one propelling fishtail member connected to the said anti-drift member through a transmission system so mounted as to perform a swinging or oscillating motion with respect to the said anti-drift member and actuated by the swimmer, wherein the said transmission system comprises a first pivot-bar substantially parallel to the main medial plane of the said anti-drift member, wherein said propelling member is arranged to substantially freely pivot about the said first pivot bar lengthwise of the latter, wherein stop means are secured to the transmission system and arranged on the pivoting path of the said propelling member about the said first pivot bar in order to oppose its rotation preferably beyond a predetermined neutral sector or angular region, wherein the rear portion of the said propelling member beyond the said first pivot bar has a surface greater than its front portion, wherein the said transmission system comprises a rigid, substantially rectangular frame, one of the sides of which is constituted by the said first pivot bar, the frame side opposite to the said first pivot bar constituting a second pivot bar about which the said frame pivots with respect to said anti-drift member, wherein the said second pivot bar is arranged in the medial main plane of the said anti-drift member and is pivotally connected to the latter through the medium of two substantially spherical joint-balls incorporated in the thickness of the said anti-drift member, wherein the said anti-drift member is provided with two lateral notches for the passage and free angular movement of both arms of the said frame interconnecting the said pivot bars and that the said notches are preferably surrounded with respective housings or enclosures allowing for the said movement, opening towards the rear and preferably relatively flat and streamlined, the said housings or enclosures projecting on either side of the said anti-drift member in substantially perpendicular relationship thereto.

An apparatus for the self-propulsion of swimmers of the type comprising an anti-drift member, a harness set connected to the said anti-drift member and adapted to be passed round the body of the said swimmer, and at least one propelling fishtail member connected to the said anti-drift member through a transmission system so mounted as to perform a swinging or oscillating motion with respect to the said anti-drift member and actuated by the swimmer, wherein the said transmission system comprises a first pivot-bar substantially parallel to the main medial plane of the said anti-drift member, wherein said propelling member is arranged to substantially freely pivot about the said first pivot bar lengthwise of the latter, wherein stop means are secured to the transmission system and arranged on the pivoting path of the said propelling member about the said first pivot bar in order to oppose its rotation preferably beyond a predetermined neutral sector or angular region, wherein the rear portion of the said propelling member beyond the said first pivot bar has a surface greater than its front portion, and wherein the said propelling means comprises a hollow portion through which the said first pivot bar passes and that the stop means are secured to the said first pivot bar and housed in the said hollow portion, and wherein said stop means are constituted by a flexible band or block, advantageously of rubber or like material, of tapering cross-section, retained in a longitudinal aperture of the said first pivot bar, the tapering or narrowest portion of the said flexible band or block projecting from the said first pivot bar and being so arranged that its opposite faces are in confronting relationship to the opposite internal faces of the said hollow portion.