US1371590A - Pawl-and-ratchet mechanism - Google Patents

Description

UNITED STATES PATENT OFFICE.

OSCAR WCODWARCD, OF BABYLON, NEW YORK, ASSIGNOR '1'0 REMINGTON TYPEWRITER COMPANY, OF ILION, NEW YORK. A COBPORATZON OF NEW YORK.

PAWL-QAND-BATCHET MECHANISM.

Original application filed May 29, 1919,

To all whom it may concern Be it known that 1, OSCAR vVooDWARo, citizen of the United States, and resident of Babylon, in the county of Suffolk, and State of New York, have invented certain new and useful Improvements in Pawl-and- Ratchet Mechanism, of which the following is a specification.

My invention relates to pawl and ratchet mechanism, and more particularly to the returning spring for and its connection with the pawl.

The main object of my invention, generally stated, is to providesimple and reliable means of the character specified.

To the above and other ends which will hereinafter appear, my invention consists in the features of construction, arrangements of parts, and combinations of devices set forth in the following description-and particularly pointed out in the appended claims.

In the accompanying drawings wherein like reference characters represent corresponding parts in the various views,

Figure 1 is an enlarged detail vertical fore-and-aft sectional View of part of a typewriter construction including the present invention, the section being taken on the line m--w of Fig. 2 and looking in the direction of the arrow atsaid' line.

Fig. 2 is an enlarged detail fragmentary transverse sectional view showing the parts illustrated'in Fig. 1, the section beingtaken on the line y-y of Fig. 1 and looking in.

the direction of the arrow at said line.

Fig. 3 isa detached detailed perspective view of the spring and pawl.

l have shown my invention in the present instance embodied in a typewriting machine and included in the pawl and ratchet mechanism between the escapement wheel and feed pinion where it is particularly available. It

' should be understood, however, that the invention may be embodied in other relations and moreespecially where the pawl 1s confined within a comparatively small space and but little room is provided for the use of a spring mounted and connected in the usual manner.

This case is a division of my application Serial No. 300,571 filed May 29, 1919, and parts disclosed and not claimed herein are claimed in said application.

Specification of Letters Patent.

Serial No. 300,571. 1920. Serial No. 868,839.

. its embodiment therein.

Patented Mar. 15, 1921.

Divided and this application filed March 26,

In the accompanying drawings I have shown only so much of a typewriting ma- (111116 as be necessary to arrive at an understanding of the present invention in The power driven carriage (not shown) travels over the top plate 1 of the machine and carries a feed rack2 which meshes with a feed pinion 3. This pinion forms part of a sleeve at which is mounted and adapted to turn with a shaft 5 in one direction and to be turned independently thereof in the oppo site direction, as will hereinafter more clearly appear. he shaft 5 is reduced at its ends to form bearing portions 6 and 7, the former of which receives its support in a bearing opening in a bracket arm 8 carried by a bracket supported by the top plate of the machine. The parts 7 of the shaft receive their support in a bearing sleeve 9 adjustably secured to an arm 10 formed as a part of the same bracket from which the arm 8 projects. An escapement wheel 11 is fixed to a hub-like supporting member 12 by screws 13, and said hub-like member is in turn secured to the shaft 5 by a screw 1%. Fixed to and projecting from the forward face of the member 12 are two pins 15 and lo the latter of which constitutes a pivot on which a pawl 16 is supported and mounted to turn. The pin 15 constitutes an anchorage for one end of a bowed wire C- spring 17, which as shown is a contraction spring substantially semi-circular in form and is tensioncd so that the free end of the spring tends to be drawn toward the anchored end. thereof. The tail of the pawl 16 is provided with an enlarged opening 18 adapted to receive the free end 19 of the spring 17, said end 19 being pin-like and formed by substantially rectangular bend the wire so that the part 19 of the spring extends axially of the hole 18 in the pawl and also in the direction of the anchorage 15'of the spring. The diameter of the opening 18 is materially greater than the diameof the wire from which the spring is conned so that the spring bears only at one nd against the pawl and against the bottom wall 20 of the opening 18. This bottom wall preferably slopes from its outer edges to the center, formin a depression which centers the free end OI the spring in the opening. The spring is thus maintained free from v with the pivotal movement of the pawl to engaging position. The power exerted by the spring on the pawl, it will be observed, 7

is almost in direct line with the anchored end of-the spring and forces the nose 21 of the pawl between the teeth 22 of a wheel 23 and into effective engagement with the inner faces 24 of said teeth 22. The parts thus act as a pawl and ratchet mechanism that causes the escapement wheel 11 to turn with the-wheel 23 in one direction and enables the wheel 23 to turn independently of the es capement wheel when the former is turned in the opposite direction. As shown in the present instance, the toothed wheel 23 is in the nature of a double wheel formed integral with the sleeve l. Thus the flange 25 on the sleeve is formed with a circular rim projecting from one side thereof and from which the teeth 22 are formed. This rim provides a recess in one side of the wheel 23 and is out completely throu 'h the thickness thereof as indicated at 26,- forming the outwardly extending ratchet teeth 22 for 3 operation with a back spacing pawl 27 and by which the wheel 23 is turned back, whereas the inner end portions 24; of the teeth form internal teeth, so tospeak, for cooperation with the pawl 16 contained within the wheel. It is in this sense that T havereferred to the wheel 23 as a double wheel, one pawl 27 co-acting with the teeth from the outside and the other pawl 16 co-acting with the teeth from inside the wheel. Although the spring 17 and pawl 16 are housed and confined within the comparatively small space within the wheel 23, a strong pawl and effective spring may be employed within said space and between the feed pinion 3 and the escapement wheel 11, the spring passing from the pawl at one side of the shaft to the pinat the opposite side thereof where the spring is bent to surround the pin and receive a very slight pivotal movement thereon during the action of the pawl.

The back spacing pawl 27, as shown, is

pivoted at 28 to a carrier 29 which in turn is pivoted at 30 to a bracket 31, the carrier being returned to normal position by a spring 32. A key controlled link 33 is pivoted at 34 to the pawl 27. An upward movement of the link 33 under control of its key is effective first to turn the pawl 27 on its pivot 28 and bring the engaging nose 27 thereof into engagement with the teethof the wheel 23 and then move the pawl 27 and wheel together, the pawl at this time moving with its carrier 29 around the pivot 30, thus effecting a back space movement of the wheel 23 and feed pinion 3, while the eS- Inassembling the parts' the, pawl 16 is introduced into position on its pivot pin 15 and the spring is readily connected therewith in the manner shown. When the combined wheel'23, sleeve 5 and feed pinion 3 are introduced into position on the shaft and the parts mounted in place as shown, the pawl and spring are inclosed within the wheel 23 and the pawl is prevented from being'displaced from its pivot.

What I claim as new'and desire to secure by Letters Patent, is

-l. The combination of a pivoted pawl having a hole therein, and a bow-spring tensioned to draw the ends of the spring one toward the other, one end of the spring being connected to a relatively fixed part while the other end is formedwith a pin-like portion that enters said hole and bears only at itspoint and only againstthe bottom of the hole. V

2. The-combination of a wheel having a recess therein and teeth thereon, a pawl contained within said recess, and a substantially semi-circular contraction spring hearing at an extreme end only against said pawl at one'side of the axis of the wheel" and connected at the other end to a relatively fixed part at the diametrically opposite sidev of the axis of the wheel, said spring being tensioned to exert a force which tends to draw the two ends of the spring toward each other in a line through the axis of the wheel. 7

3. The combination of a pawlhaving an opening therein, and a substantially semicircular springwhioh exerts'a force to move the pawl into engagement with the part with draw the ends ofjthespring toward each other, one end portion of'the spring being loosely received in' the openingin the pawl andseated therein only with a point hearing, the other end of the spring being conc-spring that has a point bearing only at,

one end against the pawl and exerts its force to draw said end of the spring toward its other anchored end thereof,

110 whichit co-acts and which is tensioned to I 6. The combination of a pawl having an opening therein, and a C-spring of smaller diameter than said opening and bearing at one end against the bottom wall thereof which is formed to center the coacting end portion of the spring in and maintain it free from contact with the side walls of the opening.

7. The combination of a pawl, and a C- spring that bears at one end against the pawl and which is mounted at its opposite anchored end to receive a slight pivotal movement.

8. The combination of a wheel comprising a disk portion having exterior teeth and a circular off-set rim forming a recess, said rim being cut through to provide a series of interior teeth, a pivoted pawl having an enlarged hole therein and adapted to engage said interior teeth, and a C-shaped spring having an angular bend at one termination, the extremity of which bears endwise at the bottom of said enlarged hole in the pawl.

Signed at the borough of Manhattan, city of New York, in the county of New York and State of New York this 24th day of March, A. D. 1920.

OSCAR WOODWARD.

Vitnesses CHARLES E. SMITH, E. M. lVELLs.

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