Product-catalog_2012

Introduction 8 / GFC Product Catalog 2012 If the gearbox is to be exactly sized by GFC, we then request from you the following specifications: 1. Purpose for use of the worm gearbox 2. Type of actuator machine 3. Actuation power P1 (in kW) 4. Actuation output speed n1 in 1/min 5. Gearbox output torque T2 in Nm 6. Gearbox output, output speed n2 in 1/min 7. Desired total transmission ratio i = n1/n2 8. Is mathematically exact transmission ratio required? 9. Type of working unit 10. Manner of operation >> continuous >> non-continuous >> do impacts occur 11. Average duration of daily operation (in h) 12. Start frequency per hour 13. Running time per hour ED in % (operation time under load) 14. For how many hours of operation must the gearbox be sized? 15. Ambient temperature in °C 16. Particular setup conditions >> outdoors >> dust exposure >> ambient temperature >> splash-proof Specifications for enquiries 17. Transmission of power from the actuator machine to the gearbox 18. a) Temporarily high torque levels b) Additional forces to be absorbed by the bearing of the transmission (in N) and their direction, resulting from any additional loads on the shaft ends by gears for belts, V-belts, chain gearboxes of gears of any type 19. Device description (series, operation position) of the transmission (see Device Description Overview) 20. Are any particular properties required? >> Specifications on the required self-locking effect (static, dynamic, definitely self-locking from the rest position) >> splicing with low slackness >> runs with particularly low noise level >> additional particularities 21. For gearboxes with connector flange for motor a) Motor cross-section b) Motor flange diameter (centering) in mm c) Motor shaft end d x l in mm 22. Which coupling will be used? >> Efficiency rating The efficiency ratings indicated in the output tables for the cylindri- cal worm gearbox are average and/or guideline values. They apply to warm-running, well-run-in cylinder worm gearboxes with roller positioning, proper lubrication and a tractioning worm shaft at the corresponding operating output speed under nominal load and con- tinuous operation. The efficiency rating increases proportionally to the increase in running speed (vg) on the splicing (output speed and sizes influence), with increasing centre-increase angle m (that is to say, with a decreasing transmission ratio i) and with improvement in the surface quality of the tooth flanks for the worm shaft. Based on previous experience, the efficiency ratings for a new gearbox (accord- ing to the prevailing transmission ratio) are lower than indicated in the output tables. These are to be multiplied by the following factors: S 40.1 – S 100.1/SS 50.1 – SS 250.1 i (worm) Factor 4 ... 14 0.97 14.5 ... 27 0.93 ab 28 0.87 SST 97 – SST 150 i (worm) Factor 4 ... 11 0.97 13.5 ... 19.5 0.93 ab 27 0.87 A good run-in is a decisive factor in the output and lifetime of the Efficiency ratings and problems for the self-locking effect transmission. When operating conditions deviate greatly from the indicated conditions (i. e., in the event of very short running times followed by long breaks) the indicated efficiency ratings cannot be attained. Therefore, we kindly request that you consult us before taking further action. Actuation to the fast mode The efficiency rating ´ with a tractioning worm wheel (transmis- sion to the fast mode) is calculated as follows: ´= 2- – With that, the overall efficiency rating h is always lower than with a tractioning worm shaft. Based on this premise, it is apparent that multiple-gear worms, due to their favorable efficiency rating – for GFC worm wheel sets, starting at the 4-gear worm – enable actua- tion from the worm wheel side (that is to say, actuation to the fast mode). Self-locking capacity For worm gearboxes, one differentiates between the static and dynamic self-locking effect. Static self-locking effect is applicable when the start efficiency rating A ≤ 0.5. A start of the worm shaft with a tractioning worm wheel is then impossible. Due to external initiation of oscillation, this self-locking effect can be (under certain circumstances) cancelled out, which means that the worm shaft can be started when the worm wheel is tractioning. The dynamic self- locking effect (self-locking capacity when running) applies when >> >> 1 >>