US1736568A - Lead clutch for mechanical pencils - Google Patents

Description

Nov. 19, 1929. w. G. AULMANN 1,736,568

LEAD CLUTCH FOR MECHANICAL PENCILS Filed April 10, 1928 I Wf flwlwazra ATTO R N EY Patented Nov. 19, 1929 UNITED STATES WILLIAM G. AULMANN, OF LOS ANGELES, CALIFORNIA LEAD CLUTCH FOR MECHANICAL PENCILS Application filed April 10,

My present invention has reference to a lead clutch for mechanical pencils of a construction that will prevent the breakage of the lead in its passage through the clutch,

regardless of any irregularities in the lead stick or any irregularities of the clutch in the pointed end of the barrel of the pencil.

As is well known lead sticks, commonly become broken in their passage through the clutch members of mechanical pencils because such clutch members are of rigid formation and likewise owing to irregularities in the machine work and assembling of such pencils. The breaking of the lead sticks is also occasioned by crookedness or irregularities in such sticks. With my improvement it is my purpose to provide a clutch through which the lead stick passes which is of a flexible nature, that is, the clutch comprises two members, a lower member being freely journaled or swivelly connected to the upper member so that there will be a yielding between these members to insure the passage of the lead stick without danger of its breaking.

To the attainment of the foregoing the invention consists in the improvement as hereinafter described and definitely claimed.

In the drawings:

Figure 1 is a side elevation of a mechanical pencil embodying my improvement, parts being broken away and parts in section.

Figure 2 is an approximately central longi- 5 tudinal sectional view of the upper element of the clutch before the lower edge has been turned or rolled in.

Figure 3 is a similar view of the lower element of the clutch.

Figure 4 is a perspective View of the lower clutch section.

Figure 5 is a section through a modification.

Referring now to the drawings in detail, the numeral 1 designates the tubular barrel of a mechanical pencil. On one end of the barrel 1 there is mounted for turning a knurled head 2 that carries a tube 3 in which 50 lead sticks 4 are received. The lower end 1928. Serial No. 268,949.

of the barrel 1 is tapered in the usual manner,

as indicated at 5.

The lower end of the tube 3 is threadedin the well known manner and this threaded portion enters the threaded bore or socket of the tubular upper element 6 of my improved clutch. The element 6 is formed intermediate its ends with an outwardly extending annular shoulder 8 whereby it is fastened in the bore of the tapered point 5. The outer or lower end of the element 7 is non-threaded and is bendable. For distinction the socket provided at this end of the element 7 is indicated by the numeral 9 and this socket is designedto receive therein outwar-dly extending beads 10 on the lower element 11 of the clutch. After the beaded end 10 has been received in the socket 9 the outer end of the member 7 is bent inwardly to provide a swivel connection between the elements 7 and 11. The element 11 has its outer end tapered, as at 12, and is provided with longitudinal slots 13 whereby the end of this element may be compressed to give the desired frictional grip on the lead.

The beads 10 may be formed on the inner end of the element 11 in any desired or preferred manner. For instance, and as disclosed by Figures 3, and 4, the inner and widened end of the said element 11 may have its sides cutaway and the material between such cut-away portions bent outwardly to form the beads, or as disclosed by Figure 5 of the drawings the slotted clutch element 11 may-have its inner end formed with a con tinuous round head 14.

My invention presents a distinct improvement on the pencil construction protected by U. S. Letters-Patent #1,581,472 and is especially adaptable for use in Connection there'- wit The simplicity of my construction and the advantages thereof will, it is thought, be understood and appreciated by those skilled in the art when the foregoing description has been carefully read in connection with the accompanying drawings, but obviously I do not wish to be restricted to the precise details herein set forth and, therefore, hold myself entitled to make such changes there from as fairly fall within the scope of what I claim.

Having described the invention, I claim:

1. The combination in a fountain lead pencil, a barrel having a pointed end, a head, a lead carrying tube secured to the bore of thebarrel and having athreaded end, of a lead clutch comprising an upper section in which the tube is screwed and a lower section which is tapered, slotted and compressed to receive and hold by friction a longitudinally movable lead and which has a loose joint con- 7 nectlon with the upper section of the clutch.

2. The combination in a fountain lead pencil, a barrel having a pointed end and a head, a threaded lead carrying tube secured to the bore of the barrel and securing the head, a lead clutch member through which the lead passes comprising an upper section in which the tube screws and a lower section which is tapered, slotted and permanently compressed to receive and hold by friction a longitudinally movable lead, having beads on the upper end of the tapered member of the clutch and the lower end of the upper section of the clutch having a lip in which is freely received the beaded end of the lower clutch section.

In testimony whereof I'atfiX my signature.

WILLIAM G. AULMANN.

Images