US605269A

US605269A - Watch-hand

Info

Publication number: US605269A
Authority: US
Publication date: 1898-06-07
Anticipated expiration: 1915-06-07

Description

(No Model.)

D. H. CHURCH. WATCH HAND. N0.605;269. Patented June 7,1898.

\A/iT'NEEEEEi INVENTU M4 @I N M %J W I mZ UNITED STATES TENT Clement DUANE H. CHURCH, OF NEWTON, MASSACHUSETTS.

WATCH-HAND.-

SPLEOIFIGATION forming part of Letters Patent No. 605,269, dated June 7, 1898.

A li ti fil d December 1'7, 1895. Serial No. 572,392. (No model.)

' of Massachusetts, have invented certain new and useful Improvements in Watch-Hands and Supporting MechanismTherefor, of which the following is a specification.

This invention relates to the attachment of watch-hands to the cannon-pinion and hourwheel of-a watch-movement; and it has for its object to provide simple andefiicient means for securing the hands in such manner that they can be applied and removed without liability 'of injury to any of the delicate parts of the watch-movement and when in place will be held positively without liability of either hand projecting into the path of the other.

To these ends the invention consists in the improvements which I will now proceed to describe and claim.

Of the accompanying drawings, forming a part of this specification, Figure 1 represents a side view of a center-staff, showing in section thereon the cannon-pinion, hour-wheel, and hands. Fig. 2 represents a section on line 2 2 of Fig. 1. Fig. 3 represents a side view of the minute-hand. Fig. 4; represents an edge view of the socket of the hour-hand.

The same letters of reference indicate the same parts in all the figures.

In the drawings, a represents the cannonpinion proper, and a the hub or sleeve portion thereof, having bearings c a for the hour-wheel h. Between said bearings the portion a is provided with longitudinal slots (L13, between which are left longitudinal sections a These sections are curved inwardly and present curved bearings to the centerstalf b. The center-staff is provided with a peripheral recess along that port-ion Which coincides with the sections a, said recess pre senting a gradual back taper from its deepest portion to a point near the outer end of the staff.

Although I have thus particularly described the construction of the cannon-pinion and its engagement with the center-stafi, I do not wish to be understood as limiting myself thereto, as the cannon-pinion and center-staff may be constructed in any other suitable manner to effect a suitable engagement between the two.

The cannon-pinion is extended outwardly beyond the outer end of the center-staff and provided with an internal screw-thread, said thread surrounding a chamber or socket at the outer end of the center-staff. The minutehand on is secured to the cannon-pinion by a screw 2', formed to engage the internal thread in the extension of the cannon-pinion. Said screw is preferably secured permanently to the minute-hand and may be either made integral therewith or in a separate piece, staked or otherwise secured in a socket formed in the minute hand. By thus attaching the minute-hand to the cannon-pinion I do away with the pressure required in forcing the minute-hand to place on its bearing on the cannon-pinion when the minute-hand has a socket pressed into frictional engagement with the cannon-pinion, as heretofore, such pressure being liable to injure the jewel on I which the inner end of the center-staff has its hearing. I also insure the firm seating of the minute-hand upon the outer end of the cannon-pinion, so that the position of the minutehand is positively assured and its liability of being deflected so as to enter the path of the hour-hand is prevented. The screw connection between the minute-hand and the cannonpinion also enables the minute-hand to be removed simply by the use of a screw-driver, no special tool being required and no liability incurred of cracking the dial by the prying operation usually required in removing the minute-hand.

My improvements further include as a means for securing the hour-hand 0 a backtapered seat 0 on the hub of the hour-wheel, said seat surrounding the outer portion of the cannon-pinion, and an elastic back-tapered socket o ,form ed on the hour-hand,said socket being transversely cut at o and made of elastic construction, so that it embraces and closely fits the seat 0. The back taper of the seat 0 and socket 0 is such that when the socket is sprung onto said seat it cannot be accidentally removed,the effect of the natural contraction of the socket on the back-tapered seat being to press the socket downwardly against the shoulder 0 ,Wl1lCl1 limits its downward movement. Hence the hour-hand may be said to be automatically seated or pressed downwardly and held out of the path of the minute-hand. The elastic socket enables the hour-hand to be readily turned on the-hub of the hour-wheel in adjusting its position, the socket being readily enlarged by forcing a screw-driver into its slot or opening, the resulting contraction insnrin g the proper bearing of the hour-hand against the shoulder, so that there is no liability of lateral displacement of the hour-hand as a result of its adjustment.

Witnesses:

O. F. BROWN, A. D. HARRISON.