US1945264A - Printing device - Google Patents

Description

Jan. 30, 1934. R, M, DUGDALE PRINTING DEVICE Filed Sept. 18. 1931 I 1 l l I l l l l l l l u I l I l Patented Jan. 30, 1934 PRINTING DEVICE Richard M. Dngdale, Dedham, Mass., assignor to Farrington Manufacturing Company, Boston, Mam., a corporation of Massachusetts Application September 18, 1931 Serial No. 563,467

5 Claims.

This invention relates to devices having pawl and ratchet mechanism and particularly to devices for printing names and addresses or other indicia on sales slips or the like as disclosed, for example, in my earlier parent applications Sr. No. 391,788 led September 11, 1929, and Sr. No. 404,291 led November 2, 1929 (of which this is in part a continuation) in which the pawl and ratchet mechanism is employed to rotate the ribbon reels. Objects of the invention are to provide devices of' this character which are more uniform and reliable in operation but which do not require such a high degree of accuracy and care in manufacture and assembly.

For the purpose of illustrating the genus of the invention a typical concrete embodiment is shown in the accompanying drawing in which;

Fig. 1 is an elevation of the interior mechanism of a printing device, showing the casing in section;

Fig. 2 is a. section on line 2-2 of Fig. 1;

Fig. 3 is a section on line 3-3 of Fig. 1; and

Fig. 4 is a section on line 4-4 of Fig. 3.

The particular embodiment of the invention chosen for the purpose of illustration comprises a base 11, a plate holder 12 rigid with the base and spaced therefrom by block 13, a casing 14 hinged to the plate holder at 15 and containing impression mechanism and ribbon feeding and reversing mechanism, and an operating handle 16 for swinging the casing and contained mechanism toward and from the plate holder 12 and for operating the impression mechanism and ribbon feeding and reversing mechanism. A suitable typographical plate 18 is adapted to be retained by the plate holder 12, one or more sheets of paper, such as'sales slips, placed thereupon, and the casing 14 swung to the position shown in Fig. 1 wherein an inking ribbon 29 is superposed upon the sheet or sheets of paper.

In this position an impression may be made upon the sheets of paper by depressing the operating handle 16 and thereby causing a verticalplunger 30 to swing a pivotally mounted roller yoke 36 to the right to position shown in Fig. l, by means of a cam surface 17 on the plunger and a cam roller 19 on the yoke, and move an impression roller 28 in a horizontal direction over the inking ribbon 29. Plunger 30 is normally retained in its uppermost position by a spring 20 which also serves to swing yoke 36 back to its normal lefthand position when the handle is released. This apparatus is more fully described and illustrated in my aforesaid applications.

The inking ribbon 29 is wound upon reels 40 and 41 and is directed to and from the lower portion of the casing by vertical ribbon guides 42 which constitute iianges of an inner casing 44 and are located adjacent opposite side walls of the main or outer casing 14.

Suitable mechanism for supporting the ribbon reels is illustrated in Figs. 1 and 2. This mechanism comprises two cylindrical stud shafts 52 and 53 rigidly mounted on the casing 14, each having enlargements in the form of flanges 63 spaced 65 from the back of the inner casing 14 and adapted loosely to receive a ratchet wheel 50 or 51 and a spacing washer 64. 4 Each ratchet wheel has pins 65 projecting forwardly therefrom immediatelyoutside the periphery of the flange 63 on the 70 shafts 52 and 53. As shown in Fig. 2 the inner casing 44 is provided with a recess 66 immediately below each ofthe reel supports and a spring is mounted on the inner casing 44, by means of struck-up ears 67, to extend into the recess 66 and bear against the spacing washer 64.

The ribbon reels are preferably constructed as shown in Fig. 4, comprising a central tubular portion 59 having radial flanges 68 and 69 at the opposite ends, the rear ilanges 69 having teeth 80 76 struck up rearwardly therefrom to interengage with the pins 65 on the ratchet wheels. As. shown in Fig. 1 the ratchet wheels have their teeth reversed with respect to each other so that the ribbon 29 is fed in one direction across the 85 bottom of the casing 14 when one ratchet wheel is actuated and in the reverse direction when the other ratchet wheel is actuated.

1 I have provided a mechanism cooperating with these ratchet wheels for actuating the ribbon reels at each operation of the device in order to advance the inking ribbon in a step by step manner to present fresh inking surfaces to the impression roller. This means preferably comprises a pawl device operable with the impression mechanism to engage one of the two ratchet wheels connected respectively to the ribbon reels. Referring to Figs. 1, 3 and 4, a tumbler 46 is pivotally mounted on the lower end of the plunger 30 between the two ribbon reels to swing toward 100 either reel. The tumbler is provided on one face with a pair of countersunk holes 47 on the opposite sides of its center, and plunger 30 carries a spring-pressed pin 49 adapted to project into either of these holes and thereby yieldingly position the tumbler adjacent one or the other of the rolls of ink ribbon. Tumbler 46 is provided with two pivotally mounted pawls 48 and 49 for engaging the respective ratchet Wheels 50 and 51 connected to reel retaining shafts 52 and 53. 110

As the plunger 30 returns to its uppermost position at the end of the printing impression, one of the pawls (48 or 49 depending upon the position of the tumbler) engages its adjacent ratchet wheel and winds a portion of the ribbon upon the corresponding reel. In this manner the ribbon is advanced in a step by step manner. The ratchet wheels are prevented from moving freely by the frictional engagement of springs 70 with spacing washers 64.

As the tumbler successively engages a ratchet wheel and causes the ribbon to wind up on the corresponding reel, continued operation of the device will transfer most of the ribbon to this reel. I prefer to reverse the direction of movement of the ribbon automatically by causing the increased thickness of ribbon on the reel upon which ribbon is being wound to bring about a reversal of position of the tumbler and thereby disconnect the tumbler from the reel which has been wound up and cause the other ratchet wheel and reel to be actuated in the opposite direction. Tumbler 46 is provided at its opposite sides, adjacent the respective rolls of ribbon, with ribbon contacting members 55 and 56. When the roll of ribbon on a reel .attains a certain thickness, it contacts with one of the ribbon contacting members 55 or 56; and a sulcient thickness of ribbon on either of the reels moves the tumbler to its opposite position, thereby causing a reversal of the ribbon.

In order to prevent the ribbon reversing tumbler from moving slowly from one position to the other in proportion to the necessarily slow change of thickness of the rolls of ribbon reversing and a consequent danger of the ribbon reversing tumbler becoming stuck in an intermediate position between the ratchet Wheels, the springpressed plunger 49 is arranged to snap the tumbler from dead-center position, that is, to the position wherein one of the arms 55 or 56 strikes the plunger 36 or the other arm (55 or 56) strikes the ribbon on the opposite reel.

According to the present invention each of the pawls 48 and 49 is provided with a guide pox-tion extending beyond the ratchet-engaging shoulder on the side opposite the pivotal connection between the pawl and tumbler or pawl-holder, this extension riding on the teeth of the ratchet and thereby holding the ratchet-engaging shoulder in uniform relation to the ratchet teeth as the shoulder is advanced into engagement with successive ratchet teeth. In this way the relationship of the pawl shoulder to the ratchet teeth is not varied as the tumbler moves from one limiting position toward dead-center in response to increase of diameter of the roll of ribbon on the reel being actuated, inasmuch as the path of the shoulder is always at the same distance from the center of the ratchet wheel notwithstanding this path shifts angularly with relation to the vertical. Thus the pawl advances the ratchet Wheel the same number of toothed intervals each time the plunger 30 is actuated. For example, if the device is constructed so that the pawl should advance the ratchet wheel an interval of two ratchet teeth for each actuation the angular shift of the tumbler on the plunger will not cause the pawl to advance the ratchet wheel more or less than two intervals at a time. Thus the present construction constitutes a distinct improvement over that disclosed in my prior applications where the movement of the pawl toward the ratchet Wheel is limited by a stop on the tumbler instead of by engagement between the ratchet teeth and a guide portion on the pawl. While my improved construction involves a pawl stop on the tumbler in the form of a ange 80, this stop functions only when a pawl is moved out of operative relationship to its ratchet wheel by the tumbler snapping past dead-center position, each pawl being held out of engagement with this stop by its tooth-engaging guide extension during substantially the whole of each interval of its operative association with its reel. In prior constructions where the recurrent movements of the pawl toward the ratchet wheel are limited by a fixed stop the pawl, stop and ratchet wheel must be carefully adjusted relatively to each other in the process of manufacture. whereas with a pawl extension riding on the ratchet teeth as here claimed the adjustment is automatic, as well as being more reliable and permanent.

ll claim:

i. A device for printing names and addresses or other indicia on sales slips or the like comprising a printing plate holder, a roller movable along the plate holder for progressively pressing successive portions of slips against a printing plate, means for conjointly moving the roller and compressing the slips between the plate holder and roller, including a spring for holding the roller in one direction, an actuator for moving the roller in the other direction against the action oi' the spring, the actuator advancing in a direction to force the roller toward the printing plate, an ink ribbon feeding along the face of the holder, reels for said ribbon, ratchet teeth for rotating either reel, pawl means mounted to move from a central position into either of two operative positions to actuate either reel in response to movement of said actuator and spring means to snap said pawl means from its central position and yieldingly hold it in either of said operative positions, said pawl means having surfaces engageable with the rolls of ribbons on said reels respectively, whereby when the roll of ribbon on one wheel reaches a predetermined diameter said pawl means is snapped into the other operative position to rotate the other reel in reverse direction.

2. A device for printing names and addresses or other indicia on sales slips or the like comprising a pair of ribbon reels with a space therebetween, a ratchet wheel associated with each reel, an actuator movable back and forth in the region of said space, a pawl for each ratchet Wheel, a tumbler swinging between two limited positions in each of which one pawl engages one ratchet wheel, means for moving the tumbler away from each reel as the roll of ribbon on the reel increases in diameter, and means for then snapping the tumbler to the other extreme position to reverse the feed, each pawl having a portionv riding on the ratchet teeth to guide its ratchet-engaging shoulder into uniform engagement with successive teeth as the tumbler moves toward its central position, and a stop on the tumbler for engaging each pawl when the tumbler snaps into posltion for the other pawl to operate.

3. A device for printing names and addresses or other indicia on sales slips or the like comprising a pair of ribbon reels with a space therebetween, a ratchet wheel associated with each reel, an actuator movable back and forth inthe region of said space, a pawl for each ratchet wheel, and a tumbler mounted on the actuator for moving the pawls relatively to the ratchet wheels respectively, the tumbler being movable between two limited positions in each of which one pawl engages one ratchet wheel, each pawl having a ratchet actuating shoulder and a guide riding on the ratchet teeth beyond the shoulder so that the path of forward movement of each pawl shoulder is at substantially the same distance from the axis of its ratchet wheel during each series of recurrent actuations of the wheel notwithstanding shifts in the position of the tumbler relatively to the wheel during the series of actuations.

4. A device for printing names and addresses or other indicia on sales slips or the like comprising a pair of ribbon reels with a space therebetween, a ratchet wheel associated with each reel, an actuator movable baclLand forth in the region of said space, a pawl for each ratchet wheel, and a tumbler mounted on the actuator for moving the pawls relatively to the ratchet wheels respectively. the tumbler swinging between two limited positions in each o! which one pawl engages one ratchet wheel, each pawl being pivoted on the tumbler intermediate its ratchet actuating shoulder and the tumbler pivot, and each pawl having an extension beyond said shoulder to ride on the ratchet teeth for the purpose herein set forth.

5. A device for printing names and addresses or other indicia on sales slips or the like comprising a ratchet wheel, a pawl holder movable back-and- Iorth past the wheel and also movable to-and-fro toward and from the wheel, and a pawl mounted on said holder, the pawl having an extension riding on the ratchet teeth to maintain a uniform relation between the pawl and teeth in various positions of the holder in its to-and-fro movement.

RICHARD M. DUGDALE.

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