Hoisting device

Abstract

.[.The invention pertains to a hoisting device, characterized by the fact that it mainly consists of a housing to which the load is suspended, and in this housing a driving pulley consisting of two half pulleys for the cable, which is suspended from a fixed point, whereby this driving pulley is provided with means which press the cable uniformly or practically uniformly into the driving pulley over a large arc, and with means which press aforesaid half pulleys away from each other at the locations where the cable enters and leaves the pulley, in such a manner that no friction occurs when the cable enters or leaves the driving pulley, whereby this pressing apart is performed in such a manner that no or practically no increase of pressure occurs on the cable on the other side of the pulley..]. .Iadd.A hoisting device having axially separable rotatable pulley portions jointly defining a cable groove and including first means to separate the pulley portions during one portion of pulley rotation to provide space for a cable to enter and leave the groove and having other means to bias the pulley portions towards each other in the other portions of pulley rotation to grip the cable in the groove. .Iaddend. .Iadd.

What I claim is: 
     
       1. Hoisting device, characterized by the fact that it mainly consists of a housing to which .[.the load is.]. .Iadd.a load is adapted to be .Iaddend.suspended and in this housing a driving pulley .Iadd.rotatable about a first axis and .Iaddend.consisting of two half pulleys for a cable, which is .Iadd.adapted to be .Iaddend.suspended from a fixed point, whereby this .[.driving.]. pulley is provided with means which .Iadd.continuously .Iaddend.press the cable .Iadd.substantially .Iaddend.uniformly .[.or practically uniformly.]. into the .[.driving.]. pulley .[.over.]. .Iadd.throughout .Iaddend.a large arc, and with means which .Iadd.continuously .Iaddend.press aforesaid half pulleys away from each other .[.at.]. .Iadd.with respect to said first axis throughout a smaller arc which extends between .Iaddend.the locations where the cable enters and leaves the pulley, in such a manner that .Iadd.substantially .Iaddend.no friction occurs when the cable enters or leaves the .[.driving.]. pulley, whereby this pressing apart is performed in such a manner that .Iadd.substantially .Iaddend.no .[.or practically no.]. increase of pressure occurs on the cable on the other side of the pulley .Iadd.and whereby the sum of the large arc and the smaller arc equals 360 degrees. .Iaddend. 
     
     
       2. Hoisting device according to claim 1, characterized by the fact that .Iadd.at least an outer peripheral portion of .Iaddend.one half pulley is .[.made of some distortable material, whereas the other half pulley is made nondistortable.]. .Iadd.resiliently deformable in a direction, with respect to said first axis, towards and away from the other half pulley.Iaddend.. 
     
     
       3. Hoisting device according to claim 1, characterized by the fact that .Iadd.at least an outer peripheral portion of .Iaddend.both half pulleys are .[.made of some distortable material.]. .Iadd.resiliently deformable in a direction, with respect to said first axis, towards and away from each other.Iaddend.. 
     
     
       4. Hoisting device according to claim 2, characterized by the fact that .[.aforesaid distortable half pulley is an integral part.]. .Iadd.said one half pulley is substantially entirely resiliently deformable.Iaddend.. 
     
     
       5. Hoisting device according to claim 3, characterized by the fact that .[.aforesaid distortable half pulleys are each integral parts.]. .Iadd.both half pulleys are substantially entirely resiliently deformable.Iaddend.. 
     
     
       6. Hoisting device according to claim 1, characterized by the fact that the means for pressing aforesaid half pulleys apart consist of a .[.roller or.]. ring which is provided between the half pulleys and inside the outer circumference .[.thereof.]. .Iadd.of the half pulleys.Iaddend.. 
     
     
       7. Hoisting device according to claim 6, characterized by the fact that aforesaid .[.roller or.]. ring is fitted within a space which is hollowed out in aforesaid half pulleys. 
     
     
       8. Hoisting device according to claim 7, characterized by the fact that aforesaid spaces in each half pulley are of dinner plate shape, with the opening of the dinner plates directed towards each other .Iadd.with respect to said first axis.Iaddend.. 
     
     
       9. Hoisting device according to claim 7, characterized by the fact that aforesaid .[.roller or.]. ring is of entirely cylindrical shape. 
     
     
       10. Hoisting device according to claim 7, characterized by the fact that aforesaid .[.roller or.]. ring is provided along its circumference with bevelled surfaces which correspond to the .[.conicity.]. .Iadd.outer peripheral configuration .Iaddend.of aforesaid spaces .[.or respectively with the bevel of the dinner plate borders.].. 
     
     
       11. Hoisting device according to claim 7, characterized by the fact that aforesaid .[.roller or.]. ring is fitted on a bearing around a disc which is excentric with respect to .[.the drive shaft of the drive pulley.]. .Iadd.said first axis and extends in a direction generally parallel thereto.Iaddend., but which itself is fitted on a bearing .[.in the center of the driving pulley or on the shaft of the driving pulley.]. .Iadd.disposed radially inwardly from said first mentioned bearing.Iaddend.. 
     
     
       12. Hoisting device according to claim 11, characterized by the fact that aforesaid excentric disc is maintained fixed with respect to the housing of the hoisting device. 
     
     
       13. Hoisting device according to claim 7, characterized by the fact that aforesaid .[.roller or.]. ring rests on three rollers which are excentrically located with respect to .[.the center line of the driving pulley.]. .Iadd.said first axis and extend in a direction generally parallel thereto.Iaddend.. 
     
     
       14. Hoisting device according to claim 13, characterized by the fact that aforementioned rollers are fitted so as to rotate freely around shafts which themselves are solidly attached to the housing of the hoisting device. 
     
     
       15. Hoisting device according to claim .[.1.]. .Iadd.6.Iaddend., characterized by the fact that the two half pulleys are joined together by means of bolts located along a circle and which are fixed in one half pulley and along which the other half pulley is free to move, whereby spring means are provided .[.such as dished springs for instance.]., between each bolt head and the adjacent half pulley, the arrangement being such that the pulley halves act on the cable, alongst the largest part of their circumference, in parallel direction and with a substantially constant pressure, the deflection imparted by said .[.roll or.]. ring occurring only at the place of entry and exit of the cable. 
     
     
       16. Hoisting device according to claim 1, characterized by the fact that the .[.groove of the cable.]. .Iadd.the cable is received within an outer peripheral groove of said driving .Iaddend.pulley .Iadd.and said groove .Iaddend.consists of a slanting surface on the inner wall of each half .[.element.]. of the pulley. 
     
     
       17. Hoisting device according to claim 16, characterized by the fact that aforesaid slanting surfaces form a groove which progressively widens from the outer .Iadd.peripheral .Iaddend.edge of the pulley towards the inside. 
     
     
       18. Hoisting device according to claim 1, characterized by the fact that aforesaid groove is of dovetail .[.shape.]. .Iadd.cross-sectional configuration.Iaddend.. .[.19. Hoisting device according to claim 1, characterized by the fact that it mainly consists of the combination of a housing to which the load is suspended, and in this housing a driving pulley consisting of two half pulleys for the cable, which is suspended from some fixed point, whereby the two half pulleys, at least one of which is made so as to be distortable, are joined together by means of bolts located along a circle and which are fixed to one half pulley, and over which the other half pulley is free to move, whereby spring means are provided, such as for instance, dished springs, between each bolt head and the adjacent half pulley, one and other in such a manner that the half pulleys are continuously being pressed towards each other by a constant adjustable and uniform or almost uniform pressure, and whereby a roller or ring is provided, between and within the outer circumference of aforesaid half pulleys, which is located excentrically and which presses the half pulleys away from each other, one and other in such a manner that on the one hand, the cable which is fitted in a dovetail shaped groove is being gripped over a large arc with a uniform or almost uniform pressure, and on the other hand, that by local and temporary distortion of one or of both half pulleys the cable can enter and leave the driving pulley without friction and without or practically without alteration of the pressure exerted by aforementioned springs upon the cable..]. .[.20. Hoisting device according to claim 1, characterized by the fact that it consists mainly of a combination of a cable pulley; distributed along the circumference of this pulley, pairs of gripping elements under spring pressure for firmly pressing the cable, and means which press the pairs of gripping elements away from each other at the locations where the cable enters and leaves the pulley..]. .[.21. Hoisting device according to claim 20, characterized by the fact that aforesaid gripping elements each consist of an L shaped block which is attached so as to be free to move on one side of the pulley and which reaches over the cable..]. .[.22. Hoisting device according to claim 21, characterized by the fact that aforementioned block is provided, at the location of the cable, with a bevelled surface..]. .[.23. Hoisting device according to claim 21, characterized by the fact that each block is provided with a leaf spring or suchlike which constantly presses the block towards the cable..]. .[.24. Hoisting device according to claim 23, characterized by the fact that aforesaid blocks are each provided with rollers which can cooperate with means which locally press the pairs of blocks away from each other..]. .[.25. Hoisting device according to claim 23, characterized by 
     
     
        the fact that aforementioned means consist of two guides or cams..]. 26. Hoisting device according to claim 2, characterized by the fact that .[.aforesaid distortable half pulley is made of at least 2 parts.]. .Iadd.only said outer peripheral portion of said one half pulley is 
     
     
        resiliently deformable.Iaddend.. 27. Hoisting device according to claim 3, characterized by the fact that .[.aforesaid distortable half pulleys are each made of at least two parts.]. .Iadd.only said outer peripheral portions of said half pulleys are resiliently deformable.Iaddend.. .Iadd.28. A hoisting device comprising: a housing;   a shaft supported by said housing for rotation about a central axis;   a first pulley member rotatively driven by said shaft and extending radially outwardly of said central axis;   a second pulley member supported for conjoint rotation with said first pulley member adjacent one side thereof;   said members having outer peripheral portions providing a radially outwardly open cable receiving groove with surfaces thereof encircling spaced axially with respect to said central axis;   biasing means carried by at least one of said members for biasing said surfaces towards each other with respect to said central axis to permit a cable to be gripped therebetween;   and means located between said members and engagable with said members to displace only that portion of at least one of said members moving through a limited arc of said conjoint rotation to permit entrance and exit of a cable to and from one portion of said cable receiving groove while retaining a cable within the entire remaining portion of said cable receiving groove substantially only by the bias of said biasing means. .Iaddend. .Iadd.29. A hoisting device as set forth in claim 28 wherein said second pulley member is supported by said first pulley member and said biasing means includes support means carried by said first pulley   
     
     
        member. .Iaddend. .Iadd.30.  A hoisting device as set forth in claim 28 wherein said biasing means comprises a plurality of circumferentially spaced members and said last mentioned means sequentially overcomes the bias of certain ones of said circumferentially spaced members. .Iaddend. .Iadd.31. A hoisting device as set forth in claim 28 wherein said last mentioned means comprises a ring rotatable about a rotative axis parallel to said central axis. .Iaddend. .Iadd.32. A hoisting device as set forth in claim 31 wherein said axes are located in a plane extending at substantially 45 degrees to a horizontal plane. .Iaddend. .Iadd.33. A hoisting device as set forth in claim 31 wherein said ring has outwardly convergent surfaces on the outer periphery thereof which are cooperable with respective outwardly convergent surfaces on said members located radially inwardly of said groove. .Iaddend. .Iadd.34. A hoisting device as set forth in claim 33 wherein the cooperation of said outwardly convergent surfaces occurs during said limited arc of said conjoint rotation. .Iaddend. .Iadd.35. A hoisting device as set forth in claim 34 wherein at least an outer peripheral portion of one of said members is resiliently deformable and during said limited arc of said conjoint rotation said cooperation of said outwardly convergent surfaces deforms said outer peripheral portion away from the other of said members with respect to 
     
     
        said central axis. .Iaddend. .Iadd.36.  A hoisting device as specified in claim 35 wherein the elastic limit of said outer peripheral portion is not exceeded during said deformation. .Iaddend. .Iadd.37. A hoisting device as specified in claim 36 wherein substantially all of said one of said 
     
     
        members is resiliently deformable. .Iaddend. .Iadd.38.  A hoisting device as set forth in claim 34 wherein at least the outer peripheral portions of both of said members is resiliently deformable and during said limited arc of conjoint rotation said outwardly convergent surfaces deform said outer peripheral portions away from each other with respect to said central axis. .Iaddend. .Iadd.39. A hoisting device as specified in claim 38 wherein the elastic limit of said outer peripheral portions are not exceeded during said deformation. .Iaddend. .Iadd.40. A hoisting device as specified in claim 39 wherein substantially all of said members are deformable. .Iaddend. .Iadd.41. A hoisting device as specified in claim 31 wherein the rotation speed of said ring is similar to the rotation speed of said members. .Iaddend. .Iadd.42. A hoisting device as specified in claim 31 wherein said rotative axis is closely transversely adjacent said 
     
     
        central axis. .Iaddend. .Iadd.43.  A hoisting device as specified in claim 31 wherein said last mentioned means is supported by said housing. .Iaddend. .Iadd.44. A hoisting device as specified in claim 31 including support means carried by said housing for the support of said last mentioned means and said last mentioned means are rotatable with respect to said support means. .Iaddend.