US3912911A

US3912911A - Reset device for digit drums and counters

Info

Publication number: US3912911A
Application number: US456835A
Authority: US
Inventors: Hans Gunter Krauss
Original assignee: ELMEG Elektro Mechanik GmbH
Current assignee: ELMEG Elektro Mechanik GmbH
Priority date: 1973-01-22
Filing date: 1974-04-01
Publication date: 1975-10-14
Anticipated expiration: 1992-10-14

Abstract

The reset device is an improvement over the device disclosed in my copending application now U.S. Pat. No. 3,835,303 to obtain a uniform holding force for the pinion shaft when in one or the other stop position as well as during transfer between the positions. The holding force is provided by two oppositely extending tongues defining an oblong slot with positive end-stops respectively at the root portions from which the tongues extend.

Description

Umted States Patent 1 [111 3,912,91 1

Krauss Oct. 14, 1975 RESET DEVICE FOR DlGIT DRUMS AND [56] References Cited COUNTERS UNITED STATES PATENTS [75] Inventor: Hans Giinter Krauss, Vohrum, 3,178,111 4/1965 Auer 235/144 HC Germany 3,441,210 4/1969 Moore et a] 235/144 SM I 3,643,072 2/1972 Szeluga 235/144 HC Asslgneel ELMEG Elektl'o-Mechamk GmbH, 3,677,468 7 1972 La Pointe et al 235 144 SM Peine, Germany 22] Filed: Apr. 1, 1974 Primary Examiner-Stephen J. Tomsky Attorney, Agent, or-Firm-Ralf H. Siegemund [21] App]. No.: 456,835 I Related US. Application Data [57] ABSTRACT Continuation-111111111 0f The reset device is an improvement over the device 1973 3,835,303- disclosed in my copending application now US. Pat. No. 3,835,303 to obtain a uniform holding force for [30] Forelgn Apphcatmn Pnonty Data the pinion shaft when in one or the other stop position Apr. 13, 1973 Germany 2318703 35 well as during transfer between the positions. The holding force is provided by two oppositely extending Cl 144 SM tongues defining an oblong slot with positive end-stops [51] Int. Cl. G06C 15/42 respectively at the root portions from which the [58] Field Of Search 235/144 HC, 144 SM, 144 EA, tongues extend,

7 Claims, 2 Drawing Figures US Patent 0a. 14, 1975 FIG.2

RESET DEVICE FOR DIGIT DRUMS AND COUNTERS BACKGROUND OF THE INVENTION The invention set forth in this application is an improvement of the device of my US. Pat. No. 3,835,303 so that this application is a continuation in part of my application Ser. No. 325,393 filed Jan. 22, 1973 now U.S. Pat. No. 3,835,303.

Specifically, the invention refers to a reset mechanism for the digit drums or cipher rolls of a counter having transfer pinions supported on a common shaft, which are disconnectable during returning of the digit drums effected by reset fingers acting on heart-shaped cams on the digit drums and the disconnection of which is limited by a stop, and a resilient element being movable during movement of the reset fingers, acts on the shaft so that at the start of the reset movement the shaft is displaced and the transfer pinions are disconnected from the digit drums. After having traversed a certain displacement path, the shaft and pinions are stopped, but upon further movement of the resilient means in the same direction a relative movement is performed between the resilient element and the shaft so that the latter assumes a different position to the former. During the course of the opposite and return movement of the resilient element the shaft and the transfer pinions follow that return immediately, and the transfer pinions are brought into engagement again with the digit drums. The return motion of the resilient element continues, now resulting in a relative movement between the resilient element and the shaft whereby the latter returns to its initial disposition with respect to the resilient element.

Such a reset mechanism has already been described in my above identified patent the disclosure of which is incorporated by reference to this application. The special advantage that is attained with such a reset mechanism is derived from the extremely simple construction having only a small number of components; the cost of assembly is correspondingly small. The construction principle involved here permits a significant reduction in the inert masses of the moving parts whereby the operational sequence has been considerablyimproved in comparison with other reset mechanisms. Moreover it is possible to combine, in a single part, the majority of components still necessary, such as the one pinion bridge and a reset slide carrying the reset fingers.

The particular embodiment of the above patent includes two beak-shaped spring tongues as the resilient element which engage springily the shaft from opposite sides, and these tongues have two arcuate recesses in their forward and rear zones forming two stop points. These two tongues extend from a common root on one side of an oblong slot between them, while their free ends define the entrance slot for insertion of the shaft. The resilient reaction of these tongues is at minimum upon insertion of the shaft, but rather strong resilient reaction is exerted upon the shaft as it approaches the root. Specifically, the resilient reaction and holding force of the two tongues differ significantly in the two holding positions as defined by arcuate slots. There is then the danger that the shaft may slip out from disposition adjacent the free ends of the tongue as it is held here with the, relatively speaking, weakest force. Normally this does not in the least constitute a danger of any consequence, but if the reset device is e.g. manually operated by a careless operator, elastromagnetic operation is provided with very high acceleration rates, such slipping out could occur.

DESCRIPTION OF THE INVENTION The object of the present invention is to improve still further a reset mechanism in accordance with the said patent and to make .it still safer in operation, so that it may also be employed reliably when the mode of operation is rather rough; for example, in the case of an electrically actuable reset. This problem is solved in accordance with the invention by the fact that the resilient element is so designed and arranged that in all its positions relative to the shaft it acts upon the latter with the substantially same force.

A uniform force to act on the shaft can be achieved in various ways; for example, the shaft can be loaded by one or even two springs lying opposite one another and running in the direction of the shaft, which consequently always acts with the same force independently of the relative positions of the springs and the shaft, and the shaft is shifted correctly between different positions.

In the preferred embodiment of the invention two resilient spring tongues, i.e. two individually resilient members are provided and their respective free ends point in opposite directions; together they define an oblong slot in which the shaft is held, and they act upon the shaft from opposite sides. With this arrangement it is always ensured that the shaft lying between the resilient members, such a spring tongue is loaded with uniform force. The oblong slot is defined by the two tongues is bounded by transversely extending edges. These edges at the ends of that slot are positive barriers or stops against further relative displacement of the shaft and define the two principle positions of the shaft inbetween which the shaft is shifted in the stated manner. Insertion of the shaft may occur through a lateral slot. The shaft is held in either end position by the same or at least very similar resilient holding forces, and these forces vary little while the shaft is pushed from one end position to the other one. It is therefor ensured, by always uniformly loading the shaft, that the friction too between the spring and the shaft is always substantially the same.

It can thus be seen that the shaft in each stage of the relative movement is held reliably by the spring, so that even in the case of jerky accelerations of the reset mechanism and hence of the springs, bouncing forward or fluttering in the case of sudden braking when the transfer pinions hit against the stop, is avoided. Since a uniform force is exerted by the spring on the shaft, the shaft is always reliably carried along by the spring during swinging out on reset slide advance and also on return thereof. Forces of inertia in the system can less easily have the effect that the shaft is displaced abnormally with respect to the spring.

The forming of the spring in the shape of two spring tongues with their free ends extending from opposite ends with respect to the shafts displacement path and pointing in opposite directions accordingly, is moreover particularly advantageous, since such a construction needs only rather little space. The resilient element, particularly the two tongues can be formed in one piece, and in integral construction with a pivotable pinion bridge not only holding the shaft and the transfer pinions but journalling them also. In this case the shaft is held guided and journalled in a pinion bridge, and it is advantageous and expedient if the two spring tongues have each the shape of an arc of a circle about the pivot of the pinion bridge, since hereby the force exerted by the two spring tongues on the shaft is kept constant better.

In furtherance of the development of the invention arcuate recesses are provided for holding the shaft in the end position.

DESCRIPTION OF THE DRAWINGS While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention, it is believed that the invention, the objects and features of the invention and further objects, features and advantages thereof will be better understood from the following description taken in connection with the accompanying drawings in which:

FIG. 1 is a side elevation of the most important parts of an embodiment of reset mechanism in accordance with the preferred embodiment of the invention in the pivotedin condition of the transfer pinions, and

FIG. 2 shows the reset mechanism as FIG. 1 with the transfer pinions swung out.

The reset mechanism illustrated in the drawings includes a pinion bridge 1 which is pivotable about an axis 2 and carries and holds a shaft 3 with transfer pinions 4 supported on it. The pinion bridge 1 is pivoted by means of a reset slide (not shown) corresponding to the reset slide and associated structure in my above identified patent. Such reset slide provides pivotal movement of the pinion bridge accordingly. Two

spring tongues

5 and 6 together constitute a resilient element and are formed in one piece with the pinion bridge. The free ends of the two tongues point in opposite directions and guide the shaft 3 between them.

These two

spring tongues

5 and 6 are transversely resilient, and from an oblong slot the longitudinal direction of which being limited by stops 7 and 8 which are formed from parts of the spring tongues and the pinion bridge respectively, adjacent to root portions of element 1 from which the tongues extend. The two

spring members

5 and 6 are slightly curved so that the slot 20 between them defines a displacement path for shaft 3 which is an arc, with axis 2 serving as center.

The spring tongue 5 ends, moreover, before the stop 7 defining a slot 21, which extends transverse to oblong slot 20 and has a recess 16, so that during assembly shaft 3 can be inserted laterally which is from above in the drawing, and into the slot. Shaft 3 is held in the slot at its righthand end as seen in the drawing, by the recess 16 which forms a resilient catch for the shaft.

A projection 9 extends from the bottom of the pinion bridge and engages a tension spring 10 by which the pinion bridge is returned in the direction towards digit drums or cipher rolls 11 when the reset slide is released. The clockwise advance of the pinion bridge 1 tensions the spring (transition as between FIGS. 1 and 2) and the spring returns bridge 1 counter clockwise when the advance is released.

These digit drums or rolls are provided each with a heart-shaped cam 12 against each of which a reset finger 13 can act, whereby the digit drums are returned and reset to a starting or zero position. These reset fingers 13 are attached each to a reset bridge which consists of blades 14 extending between the digit drums and formed in one piece with the pinion bridge 1.

If resetting of the digit drums is to be carried out, the pinion bridge 1 together with the

spring tongues

5 and 6 and the blades 14 carrying the reset fingers 13 is displaced, i.e. swung clockwise in the drawing by an external agency. This clockwise advance swing motion of bridge 1 can be obtained manually, for example, by the reset slide mentioned above, or else electromagnetically in any basically known manner. The shaft 3 with the transfer pinions 4 seated on it is thereby carried along by the

spring tongues

5 and 6 in the position shown in FIG. 1, until the transfer pinions 4 meet a stop As the pinion bridge 1 swings further due to continued advance movement of the reset slide and resulting clockwise pivot action of pinion bridge 1, the pinion shaft 2 is held through abutting engagement of the pinions and stop 15. Thus a relative movement occurs between the shaft 3 and the

spring tongues

5 and 6, during which the shaft 3 arrives in the position shown in FIG. 2. Moreover the movements of the shaft 3 and the reset fingers 13 are mutually co-ordinated so that the reset fingers 13 engage the heart-shaped cams 12 only after the transfer pinions 4 have already been swung away. In the position shown in FIG. 2 the reset finger 13 shown is lying in a holding slot in the heart-shaped cam, in which position the digit drums are completely reset.

After resetting has been effected the pinion bridge 1 is swung back i.e. counter clockwise, upon release of the reset slide and under the action of the spring 10. The shaft 3 as held by

tongues

5 and 6 is carried with it, in the position shown in FIG. 2. A constant force is exerted on shaft 3 by the

spring tongues

5 and 6, until the transfer pinions 4 are again in engagement with the digit drums 11 and cannot be moved further in this return direction. During further return swing of the pinion bridge 1, therefore, a further relative movement and displacement occurs between the shaft 3 and the

spring tongues

5 and 6, which is opposite to the relative movement mentioned above on the advance swing of bridge 1. Hence, the shaft 3 arrives again in the position shown in FIG 1 so that in the case of another reset slide advance and swinging out of the pinion bridge shaft 3 can be carried along and again in the correct disposition. Upon the return swing of the pinion bridge the travels, movements and displacements are mutually coordinated so that the reset fingers leave the guide slots in the heart-shaped earns 12 only after the transfer pin-- ions 4 lie again in engagement with the digit drums.

It can thus be seen, that uniformity of the holding force exerted by the resilient element upon shaft 3 is achieved in the following manner. When the shaft is in the disposition of FIG. 1 it engages the tongue 5 near its tip so that tongue 5 undergoes significant deflection. When in the same position, shaft 3 engages tongue 6 near the root portion from which it extends and provides for little deflection. The situation is reversed in FIG. 2, and during the transition of shaft 3 from one position in the slot to the other, resilient deflection of one tongue decreases while the other one is deflected increasingly. These opposing effects do not have to be absolutely perfectly balanced, but the changing resilient reaction of one tongue is to be approximately at least off set by the changing resilient reaction in the other. The inventive concept as well as structually realization permits obtaining similarities here and balanced conditions to more or less any desired degrees.

The device as illustrated ensures that the transfer pinions 4 upon swinging out of the pinion bridge 1 are also swung out. This is effected by the arcuate recess 16 for the shaft 3, for establishing a more definite holding position. Moreover, if the pinion bridge 1 should be actuated extremely jerkily the

spring tongues

5 and 6 will nevertheless not or at least not to a significant extent move relative to the shaft 3, since the force exerted by them on the shaft does not become smaller but remains constant.

The constant force of interaction between shaft 3 and

resilient elements

5, 6 prevents also any bouncing when the transfer pinions 4 impinge on the stop or hit the digit drums rather hard on return. Bouncing could move the shaft to and fro between the two

spring tongues

5 and 6 so that the shaft assumes an incorrect position The stops 7 and 8, in turn guarantee that the pinion bridge 1 cannot be displaced too far in either direction, but its displacement path relative to pinion bridge 1 is limited by two well defined stop positions at both ends of that displacement path. Specifically, when during reset slide advance pinion shaft 3 is stopped by stop 15, bridge 1 can travel further only for the length of the oblong slot. When shaft 3 abuts edge 8, bridge 1 must stop also. On return, shaft 3 is stopped upon reengagement of pinions and digit drums; bridge 1 can continue only for the length of the oblong slot until shaft 3 abuts edge 7. Whereupon bridge 1 must stop. Thus, travel paths and dispositions are well defined.

Stop edges 7 and 8 ensure also that shaft 3, even in the case of very extreme accelerations of the pinion bridge 1, follows always the movement of the bridge. Moreover, stops 7 and 8, located transversely to the displacement path of the shaft 3 align the shaft 3 on pinion bridge 1 at the conclusion of the advance on the forward swing of the pinion bridge, whereby any shifting of the shaft 3 between the

spring tongues

5 and 6 is corrected. Such shift in position may occur upon a very violent bouncing action upon impact of the transfer pinions 4. At the end of any displacement of the pinion bridge 1 shaft 3 always lies up against one of the stops, 7 or 8, as the case may be.

Of course the invention is not confined to the illustrated embodiment. Thus, instead of the

spring tongues

5 and 6 illustrated, other kinds of springs could also be employed. The carrying of the shaft in a pinion bridge is also not absolutely necessary. The shaft for the transfer pinions can on the contrary also be guided in slots in sideplates, in which case a corresponding spring which acts on the shaft can be applied to a member slidable in the direction of the slots in the plates. Furthermore it is also possible to provide no catch at all for the shaft or else another catch at the point at which the shaft is lying in FIG. 2.

The invention is not limited to the embodiments described above but all changes and modifications thereof not constituting departures from the spirit and scope of the invention are intended to be included.

I claim:

1. In a reset device for resetting the digit drums of a counter having transfer pinions carried on a common shaft and normally engaging the digit drums for counter operation, the reset device including reset fingers operated upon advance of the reset device for returning the digit drums to a reset position, a resilient element for holding the shaft in the position wherein the pinions engage the digit drums and being displaced upon advance of the reset device for carrying the shaft and causing the pinions to disengage from the drum, a stop being stationary relative to displacement of the resilient element and of the pinion shaft for retaining the pinions in a disengaged position while the reset device and resilient element continue to advance, the shaft being shifted in the resilient element to a second position during the continuing advance of the element, the shaft being maintained in this second position in the initial phase of return of the reset device and of the resilient element upon retraction of the reset device, the shaft being shifted in the resilient element to its initial position upon re-engagement of the digit drums and of the pinions following the initial phase of return and while the return motion of the resilient element and of the reset device continues, the improvement comprising, the resilient element holding the shaft when in the first and second position by resilient reaction transverse to the extension of a displacement path for the shaft between said first and second positions with substantially constant resilient reaction and holding force being exerted also upon the shaft by the resilient element during displacement of the shaft along said path in that the total transverse resilient reaction on the shaft varies only insignificantly for the various positions of the shaft as between the first and second positions along said path.

2. In a device as in claim 1, the resilient element having an oblong slot bounded by individually resilient members.

3. In a device as in claim 2, the resilient element including positive-stop defining edges bounding the oblong slot transverse to the direction of oblong extension.

4. In a device as in claim 3, the resilient element having a lateral entrance slot for insertion of the shaft.

5. In a device as in claim 2, the oblong slot being defined by two resilient tongues extending parallel to each other but from oppositely placed roots in opposite directions, so that the shaft has disposition adjacent one and the other root respectively in said first and second positions.

6. In a device as in claim 2, wherein at least adjacent to one end of the oblong slot a recess is provided for holding the shaft.

7. In a device as in claim 2, wherein the slot is are shaped.

Claims

7. In a device as in claim 2, wherein the slot is arc shaped.