US3786240A - Presettable subtracting counter - Google Patents

Abstract

A digit wheel is adapted to be preset to a preset position corresponding to a count higher than zero and to perform a rotational subtracting movement from said preset position to and beyond a position corresponding to a zero count. A cutoff pinion is operatively connected to said digit wheel and arranged to rotate to a signaling position in response to a subtracting movement of said digit wheel beyond said position corresponding to a zero count. A signaling lever is movable between a signaling position and a non-signaling position. Biasing means resiliently urge said signaling lever to said non-signaling position. A signal generator is under control of said lever and arranged to generate a signal when, and only when, said lever is in said signaling position. Cam means are connected to said pinion for rotation therewith and in direct engagement with said lever and arranged to permit said lever to assume its non-signaling position when said pinion is in a position other than its signaling position and to move said lever to its signaling position in response to a rotation of said pinion to its signaling position.

Description

United States Patent 1 Pfeiffer Y PRESETTABLE SUBTRACT ING COUNTER [75] Inventor: Horst Pfeifier, Aldingen Kreis Tut tlingen, Germany [73] Assignee: Firma J. Hengstler K.G., Aldingen Kreis Tuttlingen, Germany,

[22] Filed: Dec. 18, 1972 [21] Appl. No.: 316,287

[30] Foreign Application Priority Data July 22, 1972 Germany P 22 36 098.1

[52] US. CL... ...235/132 R, 235/132 E [51] Int. Cl. G06f 15/18 [58] Field of Search 235/132 R, 132 E,

- 235/132 A,6l PA [56] References Cited UNITED STATES PATENTS 2,479,482 8/1949 Edler 235/132 R 2,900,133 8/1959 Durand 235/132 R 3,231,190 1/1966 Wollar r 235/132 E 3.343.789 9/1967 Wales, Jr. et a1, 235/132 R 1 Jan. 15, 1974 Primary Examiner-Stephen J. Tomsky Attorney-George F. Dvorak et al.

[57] ABSTRACT A digit wheel is adapted to be preset to a preset position corresponding to a count higher than zero and to perform a rotational subtracting movementfrom said preset position to and beyond a position corresponding to a zero count. A cutoff pinion is operatively connected to said digit wheel and arranged to rotate to a signaling position in response to a subtracting movement of said digit wheel beyond said position corresponding to a zero count. A signaling lever is movable between a signaling position and a non-signaling position. Biasing means resiliently urge said signaling lever to said non-signaling position. A signal generator is under control of said lever and arranged to generate a signal when, and only when, said lever is in said signaling position. Cam means are connected to said pinion for rotation therewith and in direct engagement with said lever and arranged to permit said lever to assume its non-signaling position when said pinion is in a position other than its signaling position and to move said lever to its signaling position in response to a rotation of said pinion to its signaling position.

-11 Claims, 5 Drawing Figures PATENTEU 1 5974 3. 786,240

SHEET 1 OF 3 Fig.7

Fig.2

tates the cut-off pinion during the subtracting movement of the high order position wheel. from zero to nine. In this operation, only small torques can be overcome so that this rotational movement can be used only to release pawls. Two different arrangements and modes of operation of these pawls are known. In the first embodiment, the pawl is spring-biased by the cutoff lever and bears on the pinion at its addendum circle I whereas the pawl is released as the pinion rotates. For this purpose, the cut-off pinion has four teeth so that a rotation through 90 will result in a release and reengagement of the pawl. To provide this four-tooth design, four of the eight existing teeth are milled off in the range of the pawl. In the other embodiment, the cut-off pinion is similarly designed and the pawl protrudes into the gaps between the teeth of the cut-off pinion so that a cut-off rotation of the cut-off pinion will lift off the pawl to release the cut-off lever. In both embodiments, the spring-loaded cut-off lever is set and then locked by the pawl when the counter is reset to zero. These known designs have the disadvantage that they can be used only to release a pawl and'are sensitive to shakes. Besides, a continuous signal cannot be generated without a pawl and cut-off lever so that these designs are expensive and yet unreliable.

It is an object of the presentinvention to eliminate these disadvantages in an arrangement which is both simple and compact. In the presettable counting mechanism for subtracting counters, which mechanism comprises a cut-off pinion which is associated with the high order position wheel and adapted to generate a signal in response to a subtracting movement from the zero position, this object is accomplished in that the cut-off pinion comprises one or more cams for directly operating a signaling lever, which is spring-biased and generates a signal, which is maintained until the counter is reset, and the number of cams on the cut-off pinion equals one-fourth of the number of teeth of each switching pinion.

Specifically, the cut-off cam or cams operatively connected to the high order position wheel has or have together two stable positions relative to the signaling lever. These are the non-signaling position and the signaling position. Each cut-off cam has a nose, which in the signaling position of the cam is adapted to enter a groove in the signaling lever and to engage a stop in the lever when the pinion is moved bodily away from. the high order position wheel. The signaling lever is rotatably mounted on the digit wheel shaft and when pivotally moved out of its normal position initiates the generation of a signal by means of a switch finger, which for this purpose acts on a spring-biased push-button for controlling a switch. For resetting, the cut-off pinion shaft carrying the cut-off pinion is bodily movedv away from the high order position wheel. This causes the cam of the cut-off pinion to return to its initial position because the cam engages the groove in the signaling lever.

With reference to the drawings, an embodiment of the presettable counting mechanism arranged to generate a signal by means of a cut-off pinion, in accordance with the invention, will now be explained.

FIG. 1 shows the signaling mechanism in its initial position.

FIG. 2 shows the signaling mechanism in a position assumed in response to a rotation of the high order position wheel 1 from position 0 to position 9.

FIG. 3 illustrates how the resetting operation results in the elimination of the signal which has been continued after it has been initiated.

Finally, FIG. 4 shows the position assumed when the counter has been reset.

FIG. 5 is a top plan view showing the mechanism.

With reference to FIG. 1, a high order position wheel 1 is rotatably mounted on a shaft 2 and provided with two switching teeth 3 and a rim 4. The wheel I is shown in FIG. 1 in a positioncorresponding to the digit0. The high order position wheel 1 is in mesh with a cutoff pinion 5, which is provided with a'diametral double cam 6 and by means of a shaft 7 is rotatably mounted in a bridge 8. A signaling lever 9 is pivotally mounted on the shaft 2 and by-a spring loaded pushbutton ll of a switch 12 is resiliently urged against the double cam 6 and tends to move the latter to a horizontal position.

For the resetting operation, illustrated in FIG. 3, the I signal which has been maintained after it has been initiated,.is eliminated. By means of the bridge 8, an outward pivotal movement is imparted to the cut-off pinion shaft 7 so that the double cam 6 is tilted out of its signaling position and the signal generated by the switch 12 is eliminated. v

A nose 6a is associated with the double cam 6 of the cut-off pinion 5 and cooperates with the stopg'roove 9a of the signaling lever so as to impart a rotation to the cut-off pinion 5 during the outward pivotal movement of the cut-off pinion shaft 7. 1

FIG. 4 shows the position which will be assumed when the high order position wheel has been reset, for instance, to position 2 and the double cam 6 on the cut-off pinion 5 has returned to its initial position.

FIG. 5 shows the wheel 1, the shaft 2 on which the wheels 1 are mounted, and the signaling lever 9, as well as the cut-off pinion shaft 7, which is parallel to the shaft 2 and carries the cut-off pinion 5, cam 6 and nose 6a. The shaft 7 also carries a nonnal carry pinion 13, which in known manner serves for the decimal carry from the next lower order position wheel 14 to the high order position wheel 1.

What is claimed is:

l. A presettable subtracting counter, which comprises a digit wheel, which is adapted to be preset to a preset position corresponding to a count higher than zero and to perform a rotational subtracting movement from said preset position to and beyond a position corresponding to a zero count,

a cut-off pinion which is operatively connected to said digit wheel and arranged to rotate to a signaling position in response to a subtracting movement of said digit wheel beyond said position corresponding to a zero count,

a signaling lever movable between a signaling position and a non-signaling position,

biasing means resiliently urging said signaling lever to saidsignaling position,

a signal generator which is under control of said lever and arranged to generate a signal when, and only when, said lever is in said signaling position, and

cam means connected to said pinion for rotation therewith and in direct engagement with said lever and arranged to permit said lever to assume its nonsignaling position when said pinion is in a position other than its signaling position and to move said lever to its signaling position in response to a rota tion of said pinion to its signaling position.

2. A counter as set forth in claim 1', in which said digit wheel is a high order position digit wheel.

3. A counter as set forth in claim 2, in .which a carry pinion is provided, which is operable to initiate an angular step of said digit wheel and which has teeth in'a number which is an integral multiple of four, and

said cam means comprise cams in a number which is equal to one-fourth of said numberof teeth.

4. A counter as set forth in claim 3, in which said carry pinion has eight teeth and said cam means comprise two cams.

5. A counter as set forth in claim 1, in which said cam means comprise a plurality of cams, each of which is engageable with said lever.

6. A counter as set forth in claim 1, in which said pinion is rotatable to two stable positions, one of which is said signaling position of said pinion.

0 asing means comprise a spring-loaded push-button operatively interposed between said lever and said signal generator.

9. A counter as set forth in claim 1, in which said pinion is bodily movableaway from said digit wheel to an inoperative position,

said lever is provided with stop means facing said cam means, and

said cam means are arranged to engage said stop means when said pinion is in said signaling position and is moved to an inoperative position.

10. A counter as set forth in claim 9, in which said pinion is rotatable to two stable angular positions, one of which is said signaling position of said pinion, and

said cam means are arranged to rotate said pinion to the other of its stable'positions in response to a bodily movement of said'pinion to said inoperative position when said pinion is initially in said signaling position.

11. A counter as set forth in claim 9, in which said lever is formed with a recess which is defined by said stop means and said cam means comprise a nose arranged to engage said lever in said recess when said pinion is in its signaling position.

Claims (11)

1. A presettable subtracting counter, which comprises a digit wheel, which is adapted to be preset to a preset position corresponding to a count higher than zero and to perform a rotational subtracting movement from said preset position to and beyond a position corresponding to a zero count, a cut-off pinion which is operatively connected to said digit wheel and arranged to rotate to a signaling position in response to a subtracting movement of said digit wheel beyond said position corresponding to a zero count, a signaling lever movable between a signaling position and a non-signaling position, biasing means resiliently urging said signaling lever to said signaling position, a signal generator which is under control of said lever and arranged to generate a signal when, and only when, said lever is in said signaling position, and cam means connected to said pinion for rotation therewith and in direct engagement with said lever and arranged to permit said lever to assume its non-signaling position when said pinion is in a position other than its signaling position and to move said lever to its signaling position in response to a rotation of said pinion to its signaling position.

2. A counter as set forth in claim 1, in which said digit wheel is a high order position digit wheel.

3. A counter as set forth in claim 2, in which a carry pinion is provided, which is operable to initiate an angular step of said digit wheel and which has teeth in a number which is an integral multiple of four, and said cam means comprise cams in a number which is equal to one-fourth of said number of teeth.

4. A counter as set forth in claim 3, in which said carry pinion has eight teeth and said cam means comprise two cams.

5. A counter as set forth in claim 1, in which said cam means comprise a plurality of cams, each of which is engageable with said lever.

6. A counter as set forth in claim 1, in which said pinion is rotatable to two stable positions, one of which is said signaling position of said pinion.

7. A counter as set forth in claim 1, which comprises a digit wheel shaft, on which said digit wheel and said lever are independently rotatably mounted, and an operating finger, which is rigid with said lever and cooperates with said signal generator.

8. A counter as set forth in claim 1, in which said biasing means comprise a spring-loaded push-button operatively interposed between said lever and said signal generator.

9. A counter as set forth in claim 1, in which said pinion is bodily movable away from said digit wheel to an inoperative position, said lever is provided with stop means facing said cam means, and said cam means are arranged to engage said stop means when said pinion is in said signaling position and is moved to an inoperative position.

10. A counter as set forth in claim 9, in which said pinion is rotatable to two stable angular positions, one of which is said signaling position of said pinion, and said cam means are arranged to rotate said pinion to the other of its stable positions in response to a bodily movement of said pinion to said inoperative position when said pinion is initially in said signaling position.

11. A counter as set forth in claim 9, in which said lever is formed with a recess which is defined by said stop means and said cam means comprise a nose arranged to engage said lever in said recess when said pinion is in its signaling position.

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