to DMG-Lib main page
Home  · Site map  · Contact  ·

Advanced Search   Mechanism Search

RACK-AND-PINION ADDING MECHANISM WITH A RACK-TYPE ZEROING DEVICE

Click to enlargeClick to enlarge Description

Addends are entered by turning handwheel 1 which is keyed to shaft a whose rotation is transmitted by gears 2, 3, 4 and 5 to shaft d with hand c. The amount of the addend is indicated on scale e. Rotation of shaft d is transmitted by cone b to friction bushing 6 which carries hand f. Hand f turns through the same angle as hand c. At the same time, the rotation of bushing 6 is transmitted through bevel gears 7 and 8 to pinion g which displaces racks 9 and 10 in opposite directions. As it travels to the left, rack 9 shifts disk 11 which is connected by pin u to rod k in the hollow part of shaft a. Thus, as disk 11 slides along shaft a within the limits allowed by slot 1, it shifts rod k, overcoming the resistance of spring 12. After entering one of the addends, button m of rod k is pushed in. This shifts rod k and disk 11 to the right, pushing rack 9 to the right so that rack 10 moves to the left. This motion continues until disk 11 contacts the ends of both racks after which further motion is impossible. In this position of racks 9 and 10, and disk 11, hand f is returned to zero while hand c indicates the previous reading. The subsequent addends are entered in the same way. Thus, after entering a number of addends, shaft d has been turned through an angle proportional to the sum of the addends. This sum, indicated on scale e by hand c, can be transmitted to other mechanisms by gears 17 and 16, and shaft n. A locking device, consisting of gear 13 and racks 14 and 15, serves to index the position of handwheel 1, preventing unintentional rotation, and to apply a torque to shaft d which exceeds the torque produced between friction bushing 6 and shaft d. This is necessary to prevent the rotation of shaft d while hand f is being zeroed. A spring holds bevel gears 7 and 8 in engagement.
$2949$CxG,MO$

Linked items
Documents: Gear mechanisms  [Streambook]
Permanent links
DMG-Lib FaviconDMG-Lib https://www.dmg-lib.org/dmglib/handler?image=19670023
Europeana FaviconEuropeana  http://www.europeana.eu/portal/record/2020801/dmglib_handler_image_19670023.html
Data provider
ITUIlmenau TU  http://www.tu-ilmenau.de
nach oben up
×