US3030882A - High speed printing machines - Google Patents

Description

April 24, 1962 G. M. COANET HIGH SPEED PRINTING MACHINES Filed Sept. 28, 1959 3,030,882 HIGH SPEED PRINTING MACHINES Guy Michel Coanet, 21 Blvd. Magenta, Paris, France Filed Sept. 28, 1959, Ser. No. 842,841 Claims priority, application France Oct. 8, 1958 9 Claims. (Cl. 101-93) This invention relates to improvements in printing machines of the kind having continuously rotatable type wheels, called flywheel machines, which are employed in accounting or statistical machine equipment and in high speed calculators or like machines.

In cyclically operating machines of this kind, wheels or sets of wheels each bearing a complete set of engraved characters or signs are keyed side-by-side on a common shaft to form a cylinder known as a type drum or printing drum. During the operation of the machine, this drum is actuated with a continuous rotational movement generally at one revolution per machine cycle, in front of one or more paper sheets or tapes which, under the action of striker hammers selectively actuated in the course of a machine cycle, receive on one line the impression of characters or signs corresponding to data to be recorded during that cycle. In some models of the known machines, the actuation of the striking members of each printing mechanism is controlled by a triggering device driven by a mechanical or electrical pulse supplied at a precise instant in the course of a cycle, depending upon the character to be printed, by a control or decoding device. The actuation of the triggering device has the effect of bringing a member of the striker mechanism into the space between two consecutive teeth of a toothed wheel called a clock wheel, which rotates with a continuous movement in synchronism with the rotational movement of the printing drum. One tooth of the wheel then supplies to an actuating member a mechanical pulse which actuates a striker hammer for printing a predetermined character. Machines of this kind have been described, in United States patent specifications No. 2,053,063, applied for on May 18, 1934, and No. 2,244,242, applied for on April 27, 1938. Machines provided with mechanisms designed in accordance with these principles can satisfactorily etfect the printing of characters at speeds which can reach 200 printed lines per minute, but at printing speeds of the order of 300 lines per minute and more, it sometimes happens that these machines cannot ensure correct alignment of the characters printed on one line after having been in operation for some time. This is due above all to the fact that, at high speeds, the surfaces of the teeth of the clock wheel and of the members which, in each mechanism, have to transmit the striking force to the hammer and to control the instant of the said striking, become irregularly worn. Moreover, the deflection of some of the members varies appreciably in the course of the operation, depending upon the number of characters which are simultaneously printed on oneline by printing mechanisms of the machine. In addition, at high speeds, rebounding and vibration of members cause considerable disturbances in the operation of the said mechanisms.

The present invention relates to improvements which have the object of overcoming these disadvantages and of making possible an economic construction of highendurance printing machines which can operate at high speeds under good conditions. For this purpose, member called dynamic abutments" are provided to eliminate rebounding and vibration of mechanical parts which control the triggering instant of members actuated for the printing. Means are provided to minimise the mechanical energy supplied by a clock wheel" to latching means te tates Patent For a better understanding of the invention and to show how it may be carried into effect, the same will now be described with reference to the single FIGURE of the accompanying drawing which shows diagrammatically and by way of example the main members of the printing mechanism of a printing machine embodying the invention.

The drawing shows a machine in which printing mechanisms adapted to print simultaneously on a common line are disposed side-by-side in two rows, one row on each side of a plane X-Y extending through the axis of rotation A of a type drum 1. One mechanism is provided for each wheel. Since these mechanisms are identical, only one of them will be described. Each mechanism is mounted on a support plate 2, the said plates being secured by appropriate means to support bars 3 and '4 fast with the frame of the machine. Bars 62, 63 and 64 formed with slots serve to locate the support plates of the mechanism on the bars. Appropriately disposed between the type drum and the printing mechanism are one or-more paper sheets 65 with one or more carbon sheets or ribbons 66 or other means adapted for the printing. Mechanisms, which are not described because they do not form part of the invention, are provided to position and advance the paper in the machine in the course of the successive cycles.

The type drum 1 is divided along its periphery into 90 equal parts, of which 60 disposed over an angle or are entirely or partially provided with engraved characters or signs for the printing. The other 30 parts corresponding to the angle 13 bear no engraved signs. The type drum turns at the rate of one revolution per cycle. Each row of printing mechanisms is disposed along a toothed cylinder 5 forming a clock wheel."- The illustrated clock wheel is provided along its periphery with ninev teeth 60 and rotates in synchronism with the type drum 1 at the rate of 10 revolutions per cycle, the interval be tween two successive teeth of the clock wheel corresponding to the location of a character on the printing .drum. An electromagnet 6 is fixed on an adjustment plate 7. The said adjustment plate is fixed to the plate 2 by a screw 67 forming a pivot. An aperture 68 is formed in the plate 7 to enable the position of this plate on the plate 2 to be adjusted and a screw 69 is provided to lock the plate 7 in the chosen position. In addition, the plate I is guided in a slot formed in a member 70 fixed on the plate 2. The object of this adjustment will hereinafter be explained. The electromagnet 6 is provided with a movable blade 8 which is constantly pushed by a spring 9 towards the arm 10 of a control lever 11 provided with three arms and which is adapted to pivot about a pin 12 fast with the adjustment plate 7. The arm 10 is provided with a shoulder 13 which normally bears on the end of the armature or blade 8 of the clcctromagnet 6 under the actionof a spring 14 engaged, on the one hand, with a second arm 15 of the lever 11 and, on the other hand, with a point 16 fixed on the plate 7. The third arm 17 of the control lever 11 is formed with an aperture 18 and a boss 19. When the electromagnet 6 has been energised and the movable blade 8 has been to pivot about a pin fixed on the plate 7. The said pin is eccentric in relation to the abutment 21 in,' order to enable the position of the said abutment to be accurately adjusted by pivoting the said lever. A screw 43 displace- 3,03fl,882 Patented Apr. 24, 1962 able in a groove 71 in the plate 7 enables the lever 22 and the abutment 21 to be locked in a chosen position which determines the position of the boss 19 of the arm 17 when the arm 10 of the member 11 is applied against the said abutment. Pivotally mounted on the pin 12 is a member 23 called a dynamic abutment. This member has the object of preventing, in a manner hereinafter described, any possible rebound of the member 11 against the fixed abutment 21. A spring 24 normally applies the member 23 against the fixed abutment 21. The said member is provided with a projecting portion 25 so arranged that, when the arm 10 is brought against the abutment 21 by the spring 14, the said arm first abuts the portion 25 of the dynamic abutment 23, which is forced back, whereafter the arm bears without rebound against the fixed abutment 21. A release lever 26 provided with three arms is adapted to pivot about a pin 27 fixed on the support plate 2. The arm 28 of the lever 26 is provided with a pin 29 engaged in the aperture 18 in the arm 17. Engaged with a second arm 30 of the lever 26 is one end of a spring 31, whose other end is engaged with a fixed point 32 fast with the plate 2. A third arm 33 on the lever 26 is provided with a shoulder 34, against which there can bear the end of the arm 35 of a striking lever 36. The lever 36 is pivotally mounted on a pin 37 fast with the support plate 2. Engaged with the end of a second arm 38 on the lever 36 is one end of a spring 39, the other end of which is engaged with a lever 40. A third arm 41 of the lever 36, called the striking arm, provides a bearing surface for a print hammer 42 which is adapted to slide in a support 44. The hammer is normally urged against the striking arm 41 by a spring 45. The tension of the spring 39 determines the striking force of the hammer 42. This force must be adjustable at will simultaneously for all the printing mechanisms of the machine, depending upon whether the printing is effected on only one paper sheet or on a number of paper sheets between which are inserted sheets of carbon paper or the like. For this purpose, the lever 40, with which the spring 39 is engaged, is pivotally mounted on a pin 46 fixed on the plate 2. A second lever 47, which is adapted to pivot about the pin 46, bears on a bar 49, the position of which can be vertically adjusted by rotation of an eccentric shaft 50. The levers 40 and 47 can be brought into any predetermined angular position in relation to one another and locked by means of a screw 48. The angular position of the said levers determines the initial tension of the striking spring 39.

Mounted on the pin 37 hearing the striking lever 36 is a member 51 called, like the member 23, a dynamic abutment." This member is provided with an arm 52 which is constrained to turn anti-clockwise by a spring 53. A second arm 54 is provided with an extension 56 which forms an abutment. When, at the instant of the printing, the arm 35 of the striking lever 36 is released by the shoulder 34 of the arm 33, as will hereinafter be described, it first abuts the portion 56 of the dynamic abutment to which the kinetic energy of the member 36 is transmitted by shock, whereaftcr the arm 35 bears Without rebound against a fixed abutment 55. The arm 52 of the member 51, which consists of magnetic material, is normally applied against the cores or yoke of an electromagnet 57 by the spring 53 and closes the magnetic circuit of the said electromagnet. A winding 58 of one of the said cores of the said electromagnet has flowing therethrough a direct current which establishes a permanent magnetic field in the magnetic circuit. When, as a result of movement of the. arm 52 at the instant of striking, the field in the magnetic circuit of the electromagnet is varied. a winding 59 on the other core of the electromagnet supplies an induced electric pulse. The electric circuits of the windings which are incorporated in a printing mechanism are connected by links (not shown) to a connecting plug 60, which is fixed to the plate 2 and which enables the connections to the electric circuit of the machine to be established. While that portion of the type drum which corresponds to the angle {3 and which is not provided with characters travels past the print hammers in the course of one cycle, that is to say, outside the time during which a printing can take place, a re-cocking bar 61 is temporarily displaced to the left. In this movement, the said bar pushes the arm 41 of the striking lever 36 of each of the mechanisms which have been actuated in the course of the preceding cycle and returns the end of the arm 35 of the said lever against the shoulder 34 of the arm 33 of the release lever 26.

The printing mechanism operates as follows:

When the machine is in operation, the type drum 1 makes one revolution per cycle at the rate of 300 revolutions per minute in front of the striker hammer 42 and the toothed cylinder 5 (clock wheel) turns at the rate of 3,000 revolutions per minute in front of the boss 19 of the arm 17 of the member 11. The printing mechanism is cocked, that is to say, the shoulder 13 of the arm 10 of the control lever 11 is engaged on the end of the blade 8 of the electromagnet and the end of the arm 35 of the striking lever 36 is engaged on the shoulder 34 of the arm 33 of the release lever 26 in the position illustrated in the drawing. For printing a given character, an electric current pulse is sent into the winding of the electromagnet 6 at a predetermined instant of the cycle of the machine, depending upon the characters to be printed. The blade 8 attracted by the electromagnet is disengaged from the shoulder 13 of the arm 10 of the control lever 11, which pivots under the action of the spring 14, and the arm 10 strikes against the portion 25 of the dynamic abutment 23, which it pushes back and to which it transmits by shock the kinetic energy of the lever 11, whereafter the said arm again bears against the fixed member 21 without rebound. The movement of the lever 11 locates the boss 19 of the arm 17 in the path of the teeth 60 of the clock wheel 5. These teeth have at their forward end, as seen in the direction of their movement, an inclined flank and the instant when the boss 19 comes into contact with the flank of a tooth is determined by the position of the boss 19 in the path of the said teeth. Consequently, the adjustment of the position of the abutment 21 on which the arm 10 of the lever 11 bears determines the instant when the boss 19 is struck by a tooth of the clock wheel. At this instant, the said boss is driven upwards by the tooth of the clock wheel. The pin 29 of the arm 28 of the member 26, which is engaged in the aperture 18 in the arm 17, is driven in this movement, whereby the release lever 26 is pivoted and the arm 35 of the striking lever 36 is disengaged from the shoulder 34 of the arm 33. Under the action of the spring 39, the lever 36 rocks and transmits a mechanical pulse through the arm 41 to the print hammer 42, which is projected towards the type drum so as to print on the paper the character which is at that instant travelling past the printing position. The arm 35 then abuts the portion 56 of the dynamic abutment 51, which is forced back and pivots about its pin 37. The arm 35 then bears against the fixed abutment 55 without rebound, the action of the spring 39 being preponderant over the action of the spring 53. The dynamic abutment 51 is provided to prevent rebounding of the lever 36 on the abutment 55, since immediately after the printing the hammer 42 is returned against the arm 41, on the one hand by rebound after the printing, and on the other hand by the spring 45. If, at this instant, the arm 41 is in a state of vibration owing to the rebound of the arm 35 on the abutment 55, the hammer could be thrown back towards the drum and produce an undesired impression. Moreover, at the instant of the striking. the arm 52 of the member 51, which is normally applied against the cores of the electromagnet 57 by the spring 53, is removed from the said cores by the shock of the arm 35 against the portion 56 and produces a variation of the magnetic field in the magnetic circuit of the said electromagnet. This variation of the magnetic field induces in the winding 59 an electric pulse which can be transmitted to a circuit de signed to control the performance of the striking. When a printing has just been effected, the arm 35 of the striking lever 36 is maintained by the spring 39 against the abutment 35 and maintains the arm 33 of the release lever 26 in the lowered position. n the other hand, the pin' 29 of the arm 28 maintains the arm 17 of the control lever 11 in the raised position and the arm in the lowered position. When the cnergisation of the electromagnet 6 ceases, the blade d falls back in front of the shoulder 13 of the arm 10. Thereafter the re-cocking bar 61, which is temporarily displaced to the left after each printing cycle, then returns the end of the arm 35 of the lever 36 against the shoulder 34 of the arm 33 of the lever 26, the pin 29 is lowered and the shoulder 13 is returned against the blade 8. It is obvious that if, at the instant of the energisation of theelectromagnct 6, the arm 10 of the lever 111, which is disengaged, rebounded one or more times on the abutment 21 before coming to a standstill, the position of the boss 19 and consequently the instant when the latter is struck by the flank of a tooth of the clock wheel would be ill-defined and would be subject to differences in the course of successive cycles, which would result in bad alignment of the characters on the printing lines. It will be noted that the time between the travel of two successive teeth of the clock wheel past the boss 19, in the described example, is 2.2 milliseconds and the time between the instant when the arm 17 is lowered and the instant when the boss 19 is struck by a tooth is shorter than this period. It is therefore sutficient, under these conditions, for the dynamic abutment 23 to fall back on to the abutment Zll more than 2 milliseconds after the triggering of the arm 10 by the energisation of the electromagnet 6, in order that the falling back of the abutment may have no efiect on the arm 10, which has been removed from the abutment 21 by the rebound of the boss 19 on a tooth of the clock wheel. Another adjustment has been provided to permitperfect alignment of the printed characters on a line during operation of the machine. For this purpose, the plate 7, on which the electromagnet 6 and a portion of the triggering mechanism are mounted, can be pivoted about the pivot screw 67 when the screw 69 is released, by raising or lowering a lug 72. By this movement, the boss 19 of the arm 17 of the control lever'lll is displaced in the forward or rearward direction in relation 'to the direction of rotation of the clock wheel, whereby it is possible to advance or retardthe instant when the boss 19 encounters a tooth of the said clock wheel. A recess 73 formed in the plates 7 and 2 visually indicates the relative position of the two plates. r

By reason of the fact that all the triggering members of a printing mechanism are mounted on one support plate 2, as described in the present embodiment, pre-set mechanisms can be instantaneously interchanged.

Th described device has been assumed to be controlled by an electric decoding device which, for printing a character or sign, sends an electric triggering pulse into an electromagnet at a given instant. It is obvious that a printing mechanism designed in accordance with the invention may equally well be triggered in a similar manner by a mechanical decoding device controlled, for example, by devices for scanning record cards or tapes or other devices, and any modifications may be made to the form and the arrangement of the described parts without departing from the scope of the invention.

What is claimed is:

1. Cyclically operated printing mechanism including: a typedrum having a plurality of type elements thereon continuously moving through printing position, a printing hammer, a spring-urged striking lever with an arm adapted to impel said hammer agaist one of said type elements to effect printing under action of said spring, a releasing lever having two arms, one arm being adapted normally to latch said striking lever into inoperative position, and a control mechanism comprising: a toothed cylinder having evenly spaced teeth and moving in synchronism with said type drum at a greater angular velocity, a springurged control lever, said lever having an arm with a boss and with pin and slot connection to the second arm of said releasing lever, and actuating means for causing pivotal movement of the control lever at a selected instant to thereby move the boss on the said control lever into the path of the teeth on said toothed cylinder, thus causing the release of said striking lever when one of said teeth engages said boss.

2. Printing mechanism as defined in claim 1, further including abutment means, said means comprising a fixed stop member located near a second arm of said striking lever so as to arrest the latter near the end 'of its striking movement, and an elastic abutment lever with two arms. one arm being adapted to cooperate with the second arm of said striking lever and the mass of said abutment lever partially absorbing the kinetic energy of said striking lever.

3. Printing mechanism as defined in claim 2, wherein is provided an electro-magnet with a yoke and a coil winding, the armature of said electro-magnet being formed by the second arm of said elastic abutment lever, and the magnetic circuit of said electro-magnet being modified when said striking lever drives said abutment lever, thereby causing an electric pulse to be generated by said windmg.

4. Printing mechanism as definedin claim 1, further including abutment means, said means comprising a fixed stop member located near another arm of said control lever so as to limit the movement of said lever when its boss is .set into said path, and an elastic abutment lever adapted to cooperate with said other arm of said control lever, and the mass of said abutment lever being chosen to partially absorb the kinetic energy of said control lever.

5. In a cyclically operated printing mechanism including a continuously rotating type drum having at its periphery lines of type characters arranged in columns and a toothed cylinder having a number of longitudinal teeth and synchronously rotating at an angular velocity greater than that of said drum, a printing element associated to a column of said type characters, said element comprising a support plate mounted perpendicular to the axis of said drum, a printing hammer, a multi-arm striking lever hav ing a first arm end disposed to touch an end of said hammer and a second arm, a first spring attached to'said second arm for impelling said striking lever against said hammer. first latching means adapted to latch said striking lever in inoperative position against the action of said spring, said striking lever and latching means being each pivotally' mounted on said support plate; a spring-urged control lever having an arm which bears a boss and is coupled with a part of said latching means; a second latching means adapted normally to maintain the boss of said control lever out of the path of the teeth of said cylinder, said second latching means being operated by a timed impulse to unlock said control lever, whereby the boss on the latter first is set into said path -to encounter thereafter the flank of such a tooth, so that said first latching means releases said striking lever.

6. Printing element as defined in claim 5, further including abutment means fixed on said support plate, said means comprising a fixed stop member located near a third arm of said striking lever so as to arrest the-latter near the end of its striking movement, and an elastic abutment lever with two arms, one arm being adapted to cooperate also with the third arm of said striking lever and the mass of said abutment lever partially absorbing the kinetic energy of said striking lever.

7. Printing element as defined in claim 6, wherein is provided an electro-magnet with a yoke and a coil winding,

the armature of said electro-magnet being formed by the second arm of said elastic abutment lever, and the magnetic circuit of said electro-magnet being modified when said striking lever drives said abutment lever, thereby causing an electric pulse to be generated by said winding.

8. Printing element as defined in claim 5, wherein said second latching means comprises an electro-magnet whose armature is adapted to latch another arm of said control lever, said element further including an adjusting plate pivotally mounted at one point on said support plate, means to secure said electro-magnet onto said adjusting plate, a pin for pivotal mounting of said control lever on said adjusting plate and locking means, the arrangement being disposed to permit manual adjustment of the angular position of said pin with respect to said toothed cylinder, and then locking of said adjustment plate fast with said support plate.

9. Printing element as defined in claim 8, further including abutment means fixed on said adjusting plate, said means comprising a fixed stop member located near the other arm of said control lever so as to limit the movement of said lever when its boss is set into said path, and an elastic abutment lever adapted to cooperate with said other arm of said control lever, and the mass of said abutment lever partially absorbing the kinetic energy of said control lever.

References Cited in the file of this patent UNITED STATES PATENTS 2,013,533 Buhler Sept. 3, 1935 2,030,427 Buhler Feb. 11, 1936 2,227,143 Knutsen Dec. 31, 1940 2,627,807 Buhler Feb. 10, 1953 2,766,686 Fomenko Oct. 16, I956 2,895,411 Demer July 21, 1959 2,897,752 Malmros Aug. 4, 1959

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