US2294691A

US2294691A - Typewriting machine

Info

Publication number: US2294691A
Application number: US322079A
Authority: US
Inventors: Henry L Pitman
Original assignee: Underwood Elliott Fisher Co
Current assignee: Underwood Elliott Fisher Co
Priority date: 1940-03-04
Filing date: 1940-03-04
Publication date: 1942-09-01
Anticipated expiration: 1959-09-01

Description

p 1942- H; LQPITMAN 2,294,691

TYPEWRITING MACHINE Filed March 4, 1940 V/dlElV/l/A In- J7 5 INVENTOR HEN/Q! L. P/7/74/V Patented Sept. 1, 1942 TYPEWRITIN G MACHINE Henry L. Pitman, Hartford, Conn., assignor to Underwood Elliott Fisher Company, New York, N. Y., a corporation of Delaware Application March 4, 1940, Serial No. 322,079

Claims.

This invention relates to typing machines and more particularly to connections whereby an operatable part is connectible to a power driven snatch roll for a consequent power driven stroke of said part.

Such connection may include a connector, preferably a draw link, connected to the operatable part and movable into position for determining its connection with a rotary toothedsnatch-roll.

An object of the invention is to control the speed at which the toothed periphery of the snatch roll drives the link, and hence the operatable part, particularly at the start of the power driven motion of said link and part so that said start may be effected smoothly to reduce jarring and wear upon the mechanism. 7

The draw link may have a toothed pawl or rotary member pivoted thereto as the medium engaged by the snatch roll. A further object is to have such pawl or member acted upon by the snatch roll as a lever to move the draw link at a lesser speed than the linear speed of the snatch roll teeth. Forthis purpose said lever may react against an abutment. The lever action also serves to urge the pawl into proper engagement with the snatch roll.

The pawl acts as a lever, in moving the link, during a time that the pawl is being rotated from a normal position on the link to a stop position on said link.

Another object of the invention is to provide for adjustment to vary the period in which the pawl acts as a lever to control the speed of movement of the link.

The above and other objects and features of the invention will be fully understood by reference to the accompanying drawing in which:

Figure 1 is a side elevation of a type action, illustrative of an operatable part, and connections whereby said type action is connectible to a snatch roll.

Figures 2 and 3 are side elevations and represent relative positions of the parts at difierent stages.

||l represents a toothed snatch roll journaled in the frame of the machine and connected to and constantly rotated counterclockwise by a suitable motor, not shown. A type bar H is swingable upwardly and rearwardly from the normal Figure 1 position to strike a platen l2. A bell crank l3 connects said type bar to an operating lever l4 connected by a link Hi to a lever l6 fulcrumed on a transverse rod H in the framework. Pivoted at l8 to a depending arm of said lever l6 there is a lever having a rearwardly extending arm forming a draw link l9 and a forwardly extending arm 20 engageable by the key plunger 2|.

Depression of the key plunger 2| rocks said lever I9, 20 counterclockwise about I8 thereby raising the draw link Hi to bring a toothed pawl 22 pivoted on said link H! at 23 into engagement with the snatch roll l0. As will be noted from the drawing, the pitch of the teeth of the pawl 22 may be slightly less than the pitch of the teeth of the snatch roll H).

The pawl has a tail 24 which in the normal Figure 1 position of the parts extends rearwardly and lies flat upon a transverse bar 25 secured, adjustably as will later be described, to the typewriter framework.

Upon raising the draw link by operation of the key plunger 2| and hence meshing the toothed pawl 22 with the teeth of the snatch roll the latter initially rotates said pawl clockwise about the pivot 23 relatively to the link. While the pawl is being so rotated, the tail thereof reacts as a cam against a corner 26 of the abutment bar 25 so that the pawl is urged toward the snatch roll. It may be during this time and possibly for a period thereafter that the pawl acts as a lever of the second order to move the draw link to the right as viewed in the drawing. It will be seen, therefore, that while the pawl is acting thus as a lever, the draw link |9 will be moved to the right at less speed than the linear or peripheral speed of the snatch roll teeth. The pawl thus acts as a lever during the time it is rotated to the position where its corner 21 stops against an edge 28 of the draw link l9 as shown in Figure 3.

Further rotation of the snatch roll, after the Figure 3 position of the parts is attained, moves the link and pawl as a unit, that is, without further rotation of the pawl relatively to the link, until just before the type bar reaches the platen whereupon the link will have become disconnected or deflected away from the snatch roll by having encountered a knock-off 29.

The pawl 22 is thicker than the draw link I!) and is slotted below its toothed part 30 so that its consequently formed sides which include the tail 24 straddle said draw link. The slotting of the pawl 22 also forms the stopping corner 21 thereof. The link I9 may be relieved at 3| to clear the top of the pawl slot when the pawl is in the normal Figure 1 position relatively to the link I9. Said link l9 may have a return spring 32 anchored to the framework and cooperating to return the parts to normal position after the link l9 becomes disconnected from the snatch roll by encountering the knock-off 29.

The period during which the pawl acts as a lever to govern the speed of the draw link I9 relatively to the snatch roll may be varied by adjusting the abutment bar 25. To this end said abutment bar may have elongated slots 31 at its ends which permit rearward or forward adjustment of said bar relatively to the pawl 22. Fastening screws 36 for said bar 25 pass through said slots and are threaded into the framework 35 of the machine.

The bar 25 may be so adjusted that during the lever action of the pawl upon thedraw link [9 the type bar ll moves from its normal Figure 1 position to, say, the dotted line position, Figure 1. Such lever action of the pawl in moving the type bar to said dotted line position materiallyreduces the jar and wear which would otherwise attend initiation of the snatch-roll driven movement of the type action or other snatch roll driven part.

Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others,

What is claimed is:

1. In a typing machine; the combination with an operatable part, and a rotary toothed-snatchroll, of a connector connected tosaid part, a toothed pawl pivoted on said connector, said connector being movable into position for meshing said pawl with said snatch roll, said pawl being initially rotatable to a stop position relatively to said connector by said snatch roll upon meshing with the latter, and means against which said pawl reacts during its rotation relative to said connector so as to cause said pawl to act as a lever upon said connector to move said connector initially at a part-operating speed different from the linear speed of the snatch roll teeth.

2. In a typing machine; the combination with an operatable part, and a rotary toothed-snatchroll, of a connector connected to said part, a

' toothed pawl pivoted on said connector, said connector being movable into position for meshing said pawl with said snatch roll, said pawl being initially rotatable to a stop position relatively to said connector by said snatch roll upon meshing with the latter, means against which said pawl reacts during its rotation relative to said connector so as to cause said pawl to act as a lever upon said connector to move said connector initially at a part-operating speed difierent from the linear speed of the snatch roll teeth, and means for adjusting said last named means relatively to said pawl for varying the action of said pawl as a lever.

3. In a typing machine having a frame; the combination with an operatable part and a rotary toothed-snatoh-roll, of a connector connected to said part, a toothed pawl pivoted on said connector, said connector being movable into position for meshing said pawl with said snatch roll, said pawl being initially rotatable to a stop position relatively to said connector by said snatch roll upon meshing with the latter, an abutment on the frame against which said pawl reacts during its rotation relative to said connector so as to cause said pawl to act as a lever upon said connector to move said connector initially at a part-operating speed less than the linear speed of the snatch roll teeth.

4. In a typing machine having a frame; the

combination with an operatable part and a rotary toothed-snatch-roll, of a connector connected to said part, a toothed pawl pivoted on said connector, said connector being movable into position for meshing said pawl with said snatch roll, said pawl being initially rotatable to a stop position relatively to said connector by said snatch roll upon meshing with the latter, an abutment on the frame against which said pawl reacts during its rotation relative to said connector so as to cause said pawl to act as a lever upon said connector to move said connector initially at a part-operating speed less than the linear speed of the snatch roll teeth, said abutment being adjustable on said frame relatively to said pawl for varying the action of said pawl as a lever.

5. In a typing machine; the combination with an operatable part, and a rotary toothed-snatchroll, of a connector connected to said part, a toothed pawl pivoted on said connector, said connector being movable into position for meshing said pawl with said snatch roll, said pawl being initially rotatable to a stop position relatively to said connector by said snatch roll upon meshing with the latter, said pawl having a tail, and means against which said tail reacts during rotation of the pawl relatively to said connector so as to cause said pawl to act as a lever upon said connector to move said connector initially at a part-operating speed different from the linear speed of the snatch roll teeth.

6. In a typing machine; the combination of a part movable in a working stroke, a power-operable mover, a lever, a lever pivot and stop on said part, said part being normally positioned so that said lever is disengaged from said mover, means operable to move said part into position to bring an arm of said lever into engagement with said mover so that thereupon said lever is turned by said mover upon said pivot until arrested by said stop, and a substantially separate abutment against which another arm of said lever reacts, while turning about said pivot, to translate the turning of the lever into stroke movement of said part.

7. In a typing machine; the combination of a part movable in a working stroke, a power-operable mover, a lever, a lever pivot and stop on said part, said part being normally positioned so that said lever is disengaged from said mover, means operable to move said part into position to bring an arm of said lever into engagement with said mover so that thereupon said lever is turned by said mover upon said pivot until arrested by said stop, and a substantially separate abutment against which another arm of said lever reacts, while turning about said pivot, to translate the turning of the lever into at least an initial part of the stroke of said part, said stroke being completed in that said mover moves said part and lever together after said lever is arrested by said stop.

8. In a typing machine; the combination of a part movable in a working stroke, a rotary snatch-roll, a lever, a lever pivot and stop on said part, said part being normally positioned so that said lever is disengaged fromsaid snatchroll, means operable to move said part to bring an arm of said lever into engagement with said snatch-roll so that thereupon said lever is turned by said snatch-roll upon said pivot until arrested by said stop, and a substantially separate abutment against which another arm of said lever reacts, while turning about said pivot,

to translate the turning of the lever into stroke movement of said part.

9. In a typing machine; the combination of a type-actuator movable in a typing stroke, a r0- tary snatch-roll, a lever, a lever pivot and stop on said actuator, said actuator being normally positioned so that said lever is disengaged from said snatch roll, means operable to move said actuator into position to bring an arm of said lever into engagement with said snatch-roll so that thereupon said lever is turned by said snatch-roll upon said pivot until arrested by said stop, and a substantially separate abutment against which another arm of said lever reacts, while turning about said pivot, to translate the turning of the lever into stroke movement of said type-actuator.

10. In a typing machine; the combination of a part movable in a Working stroke, a rotary snatch-roll, a link connected to said part, a lever pivoted on said link, said link being movable to bring an arm of said lever into substantially rolling engagement with said snatch roll, whereupon said lever is turned by said snatch roll upon its pivot, said lever and link having stopmeans to limit the extent of turning of said lever by the snatch roll, and a substantially separate abutment against which another arm of said lever reacts, while turning about said pivot, to translate the turning of the lever into movement of said link to effect stroke movement of said part.

HENRY L. PITMAN.