VARIABLE-SPEED DRIVE SYSTEM

• US 3,601,246 A
• Filed: 07/18/1969
• Issued: 08/24/1971
• Est. Priority Date: 07/23/1968
• Status: Expired due to Term

• Current Assignee: Jacques Dubois
• Original Assignee: Jacques Dubois
• Inventors: Dubois, Jacques
• Primary Examiner(s): Wegbreit, Joseph
• Assistant Examiner(s): Stoner, Bruce H.
• Application Number:
  US04/843,152
• Time in Patent Office: 767 Days
• Field of Search: 198/16,110,135 74/190,192,217,230.16 104/25 198/76
• US Class Current: 198/334
• CPC Class Codes: B65G 23/00 Driving gear for endless conveyors; Belt- or chain-tensioning arrangements
• CPC Class Codes: B65G 2811/096 without reversal of the conveying direction

Abstract

A variable-speed drive system comprising at least one device movable along a guide path, wherein a rotating drive member is provided which is rotated at a constant speed and rolls on a bearing surface associated with said guide path. Means are provided to vary the rolling radius of the rotating member on the bearing surface in dependence upon the position of the moving device along the guide path so that the linear speed of said device may vary according to a predetermined law. The rotating member may be a pulley having a slidable flange and associated with a constant width bearing surface or a one-piece pulley associated with a variable section bearing surface.

Claims

2. A system as set forth in claim 1, characterized in that the rotating member driving the moving device is a pulley having a fixed flange and a flange which can slide along the pulley axis of rotation and which is resiliently restored towards the fixed flange;

and the bearing surface associated with the pulley is dispOsed at a variable distance from the pulley axis but is of uniform width.

3. A system as set forth in claim 1, characterized in that the rotating member driving the moving device is a one-piece pulley having flared flanges;

and the bearing surface is of variable width, means being provided to engage the pulley with such surface along the path.

4. A system as set forth in claim 1, characterized in that the rotating member driving the moving device is formed with a groove whose shape comprises two straight segments.

5. A system as set forth in claim 1, characterized in that the rotating member driving the moving device is formed with a groove whose shape comprises two curvilinear segments.

6. A system as set forth in claim 1, characterized in that the moving device comprises a roller-fitted slide, and the guide path comprises two parallel rails on which the rollers bear, the slide bearing a yoke which is disposed between the two rails and which receives the rotating member driving the moving device.

7. A system as set forth in claim 6, characterized in that the guide path rails are borne by spaced uprights which also bear support members for the bearing surface, means also being provided to adjust the distance between the last-mentioned surface and the support member.

8. A system as set forth in claim 1, characterized in that the rotating member driving the moving device has a gearwheel which meshes with a driving linktype chain disposed along the guide path.

9. A system as set forth in claim 1, characterized in that the rotating member driving the moving device is driven by a motor disposed thereon.

10. A system as set forth in claim 8, characterized in that it comprises a number of moving devices whose gearwheels mesh with the same driving chain.

11. A system as set forth in claim 1, characterized in that it is used to form a handrail for a variable-speed travelator, the system comprising a number of moving devices disposed on the same endless guide path, the various moving devices being interconnected by extensible members such as bellows.

12. A system as set forth in claim 1, characterized in that it comprises a number of devices movable along the same guide path and forming the elements of a variable-speed conveyor.

13. A system as set forth in claim 1, characterized in that it is associated with a similar system disposed parallel to it, the moving devices being interconnected by transverse members which act as support members.