referring now to the drawings and first to fig1 thereof , it may be seen that the reference number 1 designates a tubular column which can be optionally mounted in the ground ( shown ) or on a base ( not shown ). a shaft 2 is fixedly located in the interior of the column 1 . a thick - walled tubular element 3 is mounted on the shaft 2 and provided with the illustrated anti - friction bearings for taking up radial and axial loads . the element 3 is further provided with a plurality of supports 4 ( e . g ., two or more ) fixedly mounted on the outer surface of the element 3 . each support 4 is operative for supporting an arm 5 . the element 3 is further supported on a shoulder 6 of the shaft 2 . a ratchet with an annulus 7 of teeth is mounted on the shaft 2 above the element 3 . the teeth 7 each have one steeply inclined flank 7a and one gently inclined flank 7b . the ratchet is fixedly mounted on the shaft 2 by a key 8 , so that it can not rotate relative to the shaft 2 . the ratchet is further provided with a projecting circumferential flange 9 which closely abuts against an inverted cup - shaped jacket 10 . a pawl 11 is pivotably mounted on a pin 11 &# 39 ; adjacent to the teeth 7 of the ratchet . thus , the pawl 11 under the force of gravity falls into engagement with the respective teeth 7 . the pawl 11 is free to so pivot in the interior of the jacket 10 . a handle 12 is mounted on the jacket 10 . when the handle 12 is pulled towards a seat 13 mounted on the respective arm 5 , the pawl 11 engages the flank 7a of a corresponding tooth 7 of the annulus , thereby creating a force counter to that applied to the handle 12 . upon further applying the pulling force to the handle 12 in the same direction , a user sitting in the seat 13 rotates the arm 5 with the seat 13 about the shaft 2 . the movements of the user are very similar to those of a rower sitting in a boat when rowing , in which case water serves to produce resitance to the force applied by the rower onto the oar . in the present invention this function is accomplished by the pawl 11 engaging with the respective flank 7a . in further resemblance to the row action , where coupling of the water resistance is carried out through a seat of the boat on which the rower sits , coupling of the resistance in the case of the present invention is also carried out via the seat 13 in which the user sits . in order to eliminate the possibility of overriding movement of the arm 5 , which is likely to occur when a strong pulling force is applied to the handle 12 , the arm 5 is provided with an end stop 14 which prevents the handle 12 from approaching the seat 13 beyond a predetermined distance . due to this any possible damage ( squeezing etc .) to the body of the user in seat 13 is eliminated . when force is applied to the handle 12 and the arm 5 in consequence rotates about shaft 2 , the handle 12 moves in the same direction as the arm ( due to being gripped by the user or due to abutting the abutment 14 ) and during this movement the pawl 11 idly slides over the teeth 7 of the ratchet . to continue rotation the user then has to push the handle 12 away from himself and to again pull it towards himself . the movements of the body of the user are similar to those exercised by a rower . no blocking or jamming of the driving elements can take place , even when the arrangement is operated in a random manner , as children may be want to do . the seat 13 is mounted on a u - shaped frame 15 ( see fig2 ) and so fixedly installed on the arm 5 , for example screwed on , as to insure a firm connection between the seat 13 and the arm 5 . the lower open end of the frame 15 is provided with an adjustable foot support 16 . the foot support 16 can be adjusted vertically along the frame 15 and arrested by e . g ., screws in a selected position . the walls of the foot support may be provided with a rubber or plastic covering . fig3 shows another embodiment of the present invention , where there is provided a double ratchet mechanism , which comprises a rocking lever with two pawls 11 , 111 . the upper pawl 111 is urged by a spring 22 to a position in which the pawl 111 engages the annulus of teeth of an upper ratchet 17 , also rigidly mounted on the shaft 2 . the arm 5 is provided with a throughgoing passage for receiving a rocking lever 19 therein . the lever 19 during its rocking movement corresponding to the backwards movement of the upper pawl 111 along the teeth of the upper ratchet 17 , generates a driving movement on the arm 5 . such an embodiment is employed in a merry - go - round shown in fig3 and having a rockable seat 18 . instead of the handle 12 ( fig1 ) this embodiment is provided with the shaft 19 , which is mounted within the hollow arm 5 . the forward end of the lever 19 is fixedly connected with a rocking lever 23 which supports at one of its ends a lower pawl 11 and at the other of its ends the upper pawl 111 . the rear end portion of the lever 19 is connected through rods 20 with the rockable seat 18 . the rockable seat 18 moves the rods 20 and further the lever 19 which displaces the member 23 with two pawls 11 and 111 to and fro , so that by rocking the seat 18 in either direction rotation of the arm 5 will occur . the arm 5 is mounted on the jacket 10 which completely embraces the ratchets 7 , 17 and pawls 11 and 111 . the jacket 10 is further provided with an anti - friction bearing 24 and this replaces the element 3 of the first embodiment shown in fig1 . to operate the embodiment of fig3 a user on seat 18 simply shifts his body weight to and fro on the seat to make the same tilt alternately in one and the opposite direction . the tiltable seat 18 can be replaced by a slidable seat . in this case the seat will be mounted on the rails ( not shown ) and can be connected , e . g ., via a wire , rope or any other similar connecting arrangement with the rods 20 to make the same tilt and cause the lever 19 to turn . in the embodiment of fig3 it is the seat which carries out the functions of the handle 12 of the first embodiment . here , also , the arrangement can turn only in one direction whereas turning in the opposite direction is blocked . the hollow shaft 2 may have an open upper end into which the shaft 21 of an umbrella ( not shown ) may be inserted . this can be useful to protect the user against sun or rain . movable metal parts of the arrangement , especially the pawls 11 and 111 , may advantageously be provided with a sound proofing covering , or may be made of a low - noise material ( e . g ., nylon ). it will be understood that each of the elements described above , or two or more together , may also find a useful application in other types of rotary conveyors differing from the types described above . while the invention has been illustrated and described as embodied in a rotary conveyor , it is not intended to be limited to the details shown , since various modifications and structural changes may be made without departing in any way from the spirit of the present invention . without further analysis , the foregoing will so fully reveal the gist of the present invention that others can , by applying current knowledge , readily adapt it for various applications without omitting features that , from the standpoint of prior art , fairly constitute essential characteristics of the generic or specific aspects of this invention .
a rotary conveyor , particularly a merry - go - round comprises a base which has an upright axis , a first rotatable member which is mounted on the base and rotates thereon about the upright axis , at least one support rigidly connected to the first member for rotation therewith . the support is operative to support a user . a second member is operatively connected to the support for rotating the first member in response to movements performed by the user .