US2312269A - Setting mecba - Google Patents

Description

c, D. RYAN :TAL SETTING MEGHANISM' Filed May 21, 1941 Feb; 23, 1943.

Patented Feb. 23, 1943 Commodore D. Ryan andVHer-schelL.'v Atherton, Los' Angeles, Calif., assign'ors to National Postal Meter Company, Inc., Rochester, N. Y., a corporation of Delaware Application May Z1, 1941-, Serial No. :191,515v

6 Claims.

Thisv invention relates to mechanisms for setting "such devices as postage printingmachines, cash registers, and likey in which adial,v leverl or segment is movable into a plurality of vdifferent positions of rotation representative oi die'rent values, and yieldably retained in any 'one of several different positions bya detent mechanism. The detent mechanism usually comprises a disc or' segment rotatable with the setting mechanism and having a notched, arcuate edge which 'engages With a spring detent, the latter when in full engagement with a notch, yieldablyretai-ning the mechanism in a position represeritative of a certain value. The spring detent yields i-'nresponse to the application of a predetermined torque to the notched disc to permit it to rotate by the detent' mechanism isV obiectio'nablev not only because of its relatively large magnitude but because itrise's and falls `each timea tooth of the segment passes the spring datent'. It is not feasible to reduce the fforce exerted by the detent spring, as to do so' Woilldincrease the danger of into another 'position in 'which the deten't fully the vtorque required to rotate an indexing device having a detent mechanism `ol the general type referred to, Without rendering the detent mechan nism any less effective for its intended purpose, namely, to prevent accidental movement oi" 'the mechanism out of the desired position.

Another object of the invention is to pro detent mechanism that is capable of pos locking the indexing device 'against accidental -movement without linterfering with its 'noi-mal movement when actuated 'b'y the operatori.

-It is common in postage meters to provide a setting mechanism employing `a .plurality o'f 'inldexing levers each movable through asubstantial angle for setting the machine to print different values of postage. It is found that 'where the resistance to movement of the levers is "high, "the finger fatigue resulting from repeated operation `remaining two-thirds .being required to overcome the resistance afforded by the detent mechanism. This additional resistance to motioni'ntroduced accidental movement of themechanism.

l-IoWever, 'in accordance with the present invention', we have discovered that it' is possible to substantially reduce the force required to manually rock the' indexing lever Without reducing the for'ceexerted bythe detent spring, byproviding an 4auxiliary"mec'hani-srn actuated by initial movementoffthe indexing lever for carrying the spring vdetent"substant'ially clear of the toothed segment, lonly 'during movement of tlieindeXi-ng mechanism into a new* position, the mechanism releasing the spring detent for normal, full, retaining effect on its V'a'.sson'atedsegment VWhen the lirtuzleX-ing lever is released' by the'operator. Furthermore, we are able, with our 'construction,V to positively lock the toothed segment with the dete'n't except during movement of 'the mechanism into 'a new position by the operator'.

The invention may :be fully understood 'from the following detailed description with reference to the drawing of a particular embodiment 'tl:lere`of',v in which? Fig. l is a Vface view of a deterit 'mechanismin accordance with "the" present invention;

Fig. 2 is a View similar to Figi. l', lout showing the 'parts-'in a different position -o'f operation;

Fig. 3 is a sectional' vievv, vtaken in the plane IH-22H1 v01" Fig. 1;;

` Fig. 4' is a "Sectional View, taken along the line IV-fIV of Fig; l; and

Fig. 5 is a fragmentary View of a portionof the mechanismY shown in' Fig. l, but showing an -alternatlvebonstruction There is shown iin the drawing a single indexing -l-ever YI andl `associated mechanism -for rotating fa* shaft `2, Which shaft drives'an'y suitable settable' mechanism :(notv shown). The particular device disclosed is Vfor setting a printing wheel in Aa postage printing machine, and the shaft 2 is rotatable through an aro of "approximately 90 to Var'y ythe value printed from 0'V to 9. 'Ihe shaft 2 :has rigidlyoonniecte'd' thereto, as Vthrough va P11-no3', a= dial 4 on which the dilerent numerals 5 are imprinted. In aconplete `machine a pointer, a vvindovvor` other indexing devi-ce cooper- -ates` with the 'numerals '5 "to 'visibly indicate the setting of the :shaft 2 at "all times.

"I'o insure that: the shaft 2 and ldial '4 will ,always be left in position to 'print one: o'f the numerals 5, and not in a position intermediate two numbers, the dial 4 is provided over a portion of its periphery with ten notches 6, which are engageable with a detent roller 'I rotatably mounted by a pin 8 on a lever 9 which is fulcrumed at I and is urged against the dial 4 by a helical spring I I compressed between the upper end of lever 9 and a iixed support I2.

In prior constructions the indexing lever I Was solidly secured to the dial 4 and sufficient force had to be exerted on the lever to rotate the dial against the full resistance oiered by the detent roller 1. Furthermore, the resultant motion was relatively jerky because of the great changes in the resistance aiorded by the detent roller as it rolled over the teeth I4 defined by the notches 6. In accordance with the present invention, we couple the lever I to the dial 4 for limited lost motion with respect thereto, and utilize the movement of the lever in taking up the lost motion to move the detent roller substantially clear of the notches 6.

Thus the lever I is formed integrally with a flat ring I5 which lies against the side of the dial 4 and is rotatable on a hub I6 secured to the dial 4. The ring I5 is held on the hub I6 by the heads I'I of a pair of pins I8 which extend from the dial at diametrically opposite points thereon.

There is slidably secured to the face of the dial 4 a cam I9, this cam being positioned immediately back of the ring I5 and having a large slot through which the hub I6 projects so that the cam is free to slide radially in the direction of the line III-III of Fig. 1. The cam is conrlnedy to sliding movement in the direction oi the line III-III by the pins I8-I8 and a pin which all engage slots in the cam I9.

The cam I9 is provided with an outturned ear 2I which normally engages one side of the lever I and it is also provided, at a substantially diametrically opposite point, with an ear 22 that normally engages an arm 23 which projects from the ring I5 substantially diametrically opposite to the lever I. In response to counterclockwise force applied to the lever I, the ring I5 rocks freely on the hub IB and the lever I bearing against the ear 2| moves the cam I9 bodily to the left from the position shownv in Fig'. 1 into the position shown in Fig. 2, this movement being permitted by the slots engaging the pins I8 and 2). Thereafter further movement of the lever I moves the dial 4 and the shaft 2. Likewise, if force is applied to the lever I in a clockv wise direction, pressure of the arm 23 against the ear 22 shifts the cam I9 to the limit of its outward movement before the dial 4 is forced to rotate.

The cam I9 is provided with an arcuate edge 25 substantially concentric with the teeth I4 and when the cam is in its normal position as shown in Fig. 1, the edge 25 is suiiciently retracted to permit movement of the roller 1 fully into the notches 6. However, when the cam I9 is shifted to its outer position, as previously described, the arcuate edge 25 approaches the tips of the teeth I4, as clearly shown in Fig. 2, and carries the detent roller I almost clear of the teeth I4.

The net result of the improved mechanism described is that by introducing a little lost motion between the indexing lever I and its associated dial 4, the force required to rock the lever and the dial is greatly reduced. This reduction in the resistance to rotation afforded by the spring detent mechanism probably results largely because of the fact that the edge 25 of the cam I9 exerts force against the detent roller that is more directly in alignment with the direction of movement of the roller. In actual tests, a mechanism constructed as shown in the drawing has reduced the force necessary to rotate the dial from approximately 41/2 -lbs. to 21/2 lbs., a reduction oi nearly one-half in the total force required.

This'reduction in the force required is obtained without sacriiicing positive retention, since the full force of the spring II is effective to engage the roller I in one of the notches E when the indexing lever I is released.

Although the operation is much easier because ofthe use of the cam I9, the operator is still able to feel the movement of the teeth I4 past the detent roller 'I because, as already pointed out with reference to Fig. 2, the edge 25 does not carry the detent completely clear of the teeth.

In the construction described with reference to Figs. 1, 2, 3 and 4, the notches 6 are approximately triangular in shape and if suicient torque were applied to the dial 4 it could always be rotated Without employing the cam I9. However, a modied construction may be employed, as shown in Fig. 5, in which the dial 4 is positively locked against rotary movement except when the detent roller 'I' is partially disengaged from the disc, as described in -connection with Fig. 1.

It will be readily observable that the only difference between the construction shown in Fig. 1 and that shown in Fig. 5 is that the notches 6 in Fig. 5 are somewhat deeper and have straight parallel side portions 6a which engage the rollers 'I' when the latter are in locking position. By virtue of the fact that the rollers I engage against at surfaces extending approximately radially from the center of the disc 4', a torque applied to the disc develops no radial component capable of forcing the rollers 'I' out of engagement with the notches. Hence the dial 4 cannot be rotated until the detent rollers I have rst been partially disengaged from the notches 6 by the action of the cam I9. To simplify the drawing, the cam I9 has not been shown in Fig. 5, but its construction and operation will be exactly the same as that shown in Fig. 1.

Although for the purpose of explaining the invention specific embodiments thereof have been described 'in substantial detail, it is to be understood that various changes may be made in the particular constructions shown without departing from the invention, which is to be limited only to the extent set forth in the appended claims.

We claim:

'1. In an indexing device for a postage printing machine or the like, in combination, a

4rotatable member, an arcuate notched plate elef notched plate.

2. In an indexing device for a postage printing machine or the like, in combination, a rotatable plate member, an actuating member rotatable coaxially with said rotatable plate member, an element mounted on said rotatable plate member for limited radial movement with respect thereto, said actuating member engaging said element and shifting it radially in response to initial rotation of said actuating member relative to said rotatable plate member, and means thereafter coupling said element positively to said rotatable plate member for driving the latter as said actuating member is rotated, brake means comprising a radially movable element for controlling rotation of said rotatable plate member, the aforesaid shifting of said radially movable element being adapted to partially disengage said brake means.

3. In an indexing device for a postage printing machine or the like, in combination, a rotatable member, a coaxial rotatable actuating member, an arcuate notched detent plate on said rotatable member, a radially movable, springactuated detent engaging said notched plate, a smooth, arcuate member mounted for radial movement on said rotatable member between a first position in which it is retracted clear of said detent and a second position in which it engages the detent and at least partially disengages said detent from said notched member, and means responsive to initial movement of said actuating member for shifting said smooth, arcuate member from said rst to said second position, said means thereafter coupling said actuating member to said rotatable member for driving the latter.

4. In an indexing device for a postage printing machine or the like, in combination, a rotatable member having an arcuate notched edge portion, a spring detent radially movable with respect to said rotatable member for engaging the notched edge portion of said rotatable member, a cam element mounted on said rotatable member, an actuating member rotatable coaxially with said rotatable member, and lost motion means coupling said actuating member and said cam element to said rotatable member, said actuating member moving said cam element during said lost motion period to partially disengage said detent from the notched edge portion of said rotatable member, whereby said detent engages only the outer ends of the teeth forming said notched edge portion as said actuating member moves said rotatable member.

5. In an indexing device for a postage printing machine or the like, in combination, an actuating member, a rotatable platemember adapted to be moved by said actuating member, rack means formed on the periphery of said plate'member, a spring detent adapted to engage said rack means, the inner portions of the teeth of said rack having Walls extending substantially radially with respect to the axis of said rotatable plate member, the outer portions of the Walls of each tooth extending toward each other to form cam surfces on the ends of each tooth, and means movable by the initial movement of said actuating member to disengage said detent from the inner portions of said teeth so that only the cam-shaped portions of the teeth engage the detent as said actuating member turns said plate member.

6. In an indexing device for a postage printing machine or the like, in combination, a rotatable member, an arcuate notched plate element, a cooperating spring detent element radially movable to follow the notches in said plate element in response to relative rotation between said elements, one of said elements being mounted on said rotatable member, an actuating member, means mounting said actuating member for rotation with said rotatable member and also for shifting movement transversely of the axis of rotation of said rotatable member, means coupling said actuating member to said rotatable member with lost motion therebetween, and means responsive to movement of said actuating member relative to said rotatable member through said lost motion for radially moving one of said elements to partially disengage said detent element from said notched plate element.

COMMODORE D. RYAN. HERSCHEL L. ATI-IERTO'N.

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