US1818690A - Pawl for ratchet-mechanisms - Google Patents

Description

g- 1931- E. L. CA'RLSON PAWL FOR RATCHET MECHANISMS Filed May 15, 1929 Patented Aug; 11, 1931 UNITED STATES ELOF L. CARLSON, or BRISTOL, ooNNEorIconnssioNoT-r ToTHn,E.1NoRAnAM co.,

Y or BRISTOL, CONNECTICUT;A CORPOBATION-y PAWL non narcnn'rrncnanisiyr fi Application filed May 15,

My invention relates to an improvement.

in pawls for ratchet-mechanisms, the object being to produce a resilient pawl having a hard thin driving-edge or tip whereby it is .5 adapted to be used with fine-toothed ratchet wheels, though not so limited,.and, on account of its resiliency, to ride over the teeth of such wheels with the minimum of noise,

and, on account of its hardness, to resist prolonged incessant wear.

With these ends in view, my invention consists in a pawl characterizedbvhaving a body to which a relatively-thin resilient sheet-metal tip is applied. -My invention further consists in apawl characterized as above and having certain details of construction as will be hereinafter described and particularly pointed out in the claims.

In the accompanying drawings:

Fig. 1 is a view in front elevation of an electric clock embodying my improved resilient-tipped pawl;

Fig. 2 is a detached perspective view of my improved pawl on an enlarged scale;

Fig. 3 is a view thereof in transverse section on the line 33 of Fig. 2;

Fig. 4 is a perspective view of the pawlbodv; and

Fig. 5 is a similar view of the springtip thereof.

As herein shown, my invention is applied to the driving-mechanism of an electric clock but its use is not so limited, being applicable 35 indeed to a great variety of situations in which pawls are used. 1

As herein shown, my improved pawl consists of a fla-t struck-up sheet-metal body 10 and a resilient sheet-metal tip 11 consisting, by preference, of a relatively-long narrow strip of hardened spring steel having near its inner end an oblong rectangular opening 12 receiving arivet 13 of corresponding shape and formed integral with one edge of the pawl-body 1O aforesaid, the rivet being headed down after the resilient tip 11 has been applied to it, as shown in Fig. 3. The flat body 10 and Hat tip 11 are thus disposed at a right angle to each other. The pawlbody 10 is formed with a pivot-hole 141 receiv- 1929. Serial No. 363,302.

ing a stud 15 upon which the pawl swings and which is mounted in the arm 16 of an armature 17 rocking upon a stud 18 and coacting with the magnet 19 of an electric clock, with the details of which we are not F5}, I

here concerned and to which I have applied the general designating numeral 20.

The pawl-body 10 is also formed with a hook 21 receiving one end of a helical pawlspring 22, the opposite end of which is en- &0 gaged with a pin 23 of the clock 20. The free end of the pawl-tip 11 is held by the said spring 22 in engagement'with the teeth of a ratchet-wheel 24 forming a member ofthe drlvlng mechanism; of the clock, the said ie;

wheel being also engaged by a pawl 25 engaged by a flat spring'26 and preventing the said wheel 24 from being reversely rotated when the resilient pawl-tip 11 is being dragged back over its teeth by the rocking of 51 7i) the armature l7'under the influence of the magnet 19.

By providing my improved pawl with an independent resilient tip .of hardened sheet-metal, thetip may be made so thin as to M5 provide for its-unfailing and accurate engagement with the teeth of a ratchet-wheel, however fine, and the metal of the tip being very hard, it will not wear unduly, though subjected to incessant prolonged use. More-1: over, on account of the resiliency of the tip,

it rides over the teeth of the ratchet-wheel in ratcheting back, as the term is, with the minimum amount of noise.

Myimproved pawl is, therefore, peculiarly adapted for use in delicate mechanisms in which a pawl having a thin durable edge is called for. i

I claim:

1. A pawl having a struck-up sheet-metalfwo the said body-member; and a relatively-hard spring-tempered sheet-metal tip engaged at its outer end with the teeth of the said ratchet-wheel and secured at its inner end to 5 the said body-member and extending substantially-radially outward therefrom in a plane perpendicular to the path of swinging movement of the pawl around the said pivot and perpendicular to the path of movement of the said ratchet-wheel.

In testimony whereof, I have signed this specification.

ELOF L. CARLSON.

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