Патент USA US2564730

AugU 21, 1951
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H. W. SAMS
2,564,727
MECHANICAL PENCIL
Filed April '7, 1948
`
(Ittornegs
Patented Aug. 2l, 1951
2,554,727
UNITED STATES ÉÈ‘iêi'ÈEIÑ'I‘y Q_ITITICEIv Y
2,564,727l '
MEonANroAL PENCIL
Herbert W. Sams, Atlanta, Ga., assignor to
Scripto, Inc., a corporation of Georgia
Application April 7, 1948, Serial No. 19,469
7 Claims. (C1. 1Z0-_18)
1
This invention relates to mechanical pencils
having a screw type lead feed mechanism. and
more especially to- an improved construction for
pencils of this sort in which a novel form of
ejector pin is incorporated which eliminates end ~
play in the lead-feed, andin which the lead feed
mechanism is otherwise arranged for ¿assembly
in the 'pencil so that particularly smooth operat
ing characteristics are obtained.
1
2
keyed with and retained on the guide tube I6 by
aA dimple or boss formed in the guide Atube to fit
a»..slot in .the end of the mounting sleeve- as illus
trated at 2l) in Fig. 1. Also», thefeed tube I5,
which is disposed in telescoped relation. for rota
tion on the guide-tube I B, is fitted with a lock
sleeve 2`I similarly keyedand retained in position
by a projection or bossV on the guide tube engag
ing a slot in the lock sleeve as indicated at 22
Also, according to the present invention, the lil in F'ig. 1. The feed tube I5 and guide tube i5
various-'elements of the pencil construction are
arranged to insurealignment of the barrel-and
the lead feed mechanism upon assembly.
. The present invention is described in detail
below in` connection with the» accompanying
drawing,
in which:v
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.
»
.
v Fig. 1 is a vertical section of a mechanical
pencil constructed in. accordance with the present
invention;
.
.
-
»
are telescoped so that the lower end face of the
lock sleeve 2| rests on. the top end face of the
mounting sleeve I9, a ñber washer»23,being inter
posed to provide for smooth relative rotation` of
these
sleeves.
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f
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»
The lead feed mechanism I4 is anchored in
the lower portion I2 of the barrel. Iû by a press
ñt of the mounting sleeve I9, in the writing; end
of the lower portion >l2 which is constricted as
_.Fig. 2 is a section aken on the line 2-2 in 20 shown in the drawing. When pressed in place,
a portion of the mounting sleeve I9 extends from
Fig. 3 is a section taken on the linev 3_3 in
the writing end of the lower barrel I2, and this
Fig',
1;
,
L.
Fig. 1;
„
..
_
_
>
.
extending portion of the mounting sleeve I9 is
. Fig. 4 is an enlarged detail of the writing point
of the pencil as seen from the right side inFig. 1
with the lead feed mechanism in full downward
position.;
.
.
.
Fig. 5 is a detail of the ejector pin and lead grip
sleeve;
.
Fig. 6 is a corresponding, partly
right .sidefdetailç
.
.Y
.
fragmentary.
f
. 1
.
~ .
Fig. 8 is a fragmentary detail illustrating the
manner in which the lead feed mechanism is
assembled.
internally threaded, metal, tip member 25. The
writing end of this lower barrel portion I2 is
shouldered as shown at 26 and the tip member
25 is formed Ywith a flange 2l adapted >to seat
externally on this shoulder ‘26r and thereby align
the lower barrel portion`> I2 with. the tip mem
ber 25.
Fig. 7` is a sectional detail taken on the line
'll-'I in Fig. 5; and.
formed with external threads 24 to receive an
.
. [As shown in the drawing, the mechanical
,
Alignment of the parts
v
is particularly
f
~ impor
tant at this point, because any surfaceirregular
ity between associatedV parts at the writing end
of the pencil not only impairsv its appearance but
is an annoyance in use when the pencil is grasped
at this portion for writing. The above described
pencil of the present invention comprises a bar
arrangement of the ñange 2'7.> on the tip member
rel vIt preferably formed of moulded plastic and
25 for seating externally on the shoulder 26 at
having separate upper and lower portions I I and
the writing end of the lower barrel portion l2
I‘2. The upper portion II of the barrel Iil serves 40 is especially Well adapted for obtaining effective
as an operating cap, and may be iitted in any
alignment of the parts when a moulded plas
convenient manner with a pocket clip I3 if de
tic barrel is used in the pencil construction.
sired,.while the lower portion I2 provides an
Molded plastic parts have a tendency to give
anchoring. housing for a lead feed mechanism lli.
45 or spread under pressure in assembly, and the
The lead feed mechanism> I4 is arranged as a
arrangement of the flange 2l on the tip member
unit assembly for disposition in the barrel I5
25 not only forces alignment of the lower barrel
andincludes a helically slotted feed-tube l5, a
portion I2 but contains it against the mounting
longitudinally slotted- guide tube I6, and a lead
sleeve i9 so that it cannot give or spreadT
carrying and ejecting mechanism consisting of 50
Operation of the lead feed mechanism I4 is
a lead grip sleeve Il and an ejector pin I8.
provided for through an operating sleeve 2li-which
i As'mentioned abo-ve, the» lead feed mechanism
isv fitted snugly, but freely for rotation, in the
I4 is assembled as aunit, and for this purpose
lower barrel portion I2, and is contracted at its
the >guide tube It is fitted with a mounting sleeve
lower end, as indicated at. 2S in Fig. l, to grip
I9 at its lower end, this mounting sleeve le being
the lock sleeve 2l: fitted on '..the- feed .tube I5.
2,564,727
3
The operating sleeve 28 extends beyond the upper
end of the lower barrel portion I2 so that the
upper barrel portion II may be fitted over it as
well, and ñats 3l) are formed in a portion of this
extending length to set up ribs 3l for frictional
contact with the upper barrel portion II (com
pare Figs. 1 and 3). As the guide tube IB is
fixed in the lower barrel portion I2 by the mount
ing sleeve I5, this frictional contact of the upper
4
posed to extend through a longitudinal slot in a
guide tube and engage a helical slot in a feed tube
so that relative rotation of the feed tube and guide
tube causes feeding movement of the ejector pin.
This same general arrangement is used according
to the present invention, but with an improved
arrangement of spaced lugs 42 on the ejector pin
I8 for engaging the feed tube I5 so that end play
in the lead feed is eliminated and a particularly
barrel portion II with the operating sleeve '28 10 smooth feeding movement is obtained.
The spaced lugs 42, as illustrated in detail in
allows the lead feed mechanism I4 to be actuated
Figs. 5, 6 and 7 of the drawing, are disposed on
from the upper barrel portion II through the
the extending edge of a lateral projection 43
_lock sleeve 2| keyed on the feed tube I5 and to
formed on the ejector pin I8 to extend through
which the operating sleeve 28 is fixed.
the longitudinal slot in the guide tube I6. These
The operating sleeve 23 is further formed with
lugs 42 are formed with wing portions as shown
a circumferential expanded portion 32 positioned
extending transversely over the exterior surface
in correspondence with the joint between the up
of the guide tube I6 and oriented at an angle for
per and lower barrel portions I I and I2 for align
engaging the helical slot in the feed tube I5, and
ing the barrel portions at this point. Also, the
the lugs 42 are spaced to ride opposed faces of suc
upper barrel portion II is advantageously fitted
cessive turns of the helical slot. That is, the
at this joint with an external ring member 33 to
spacing of the lugs 42 is proportioned to ride the
condition it, similarly to the writing end of the
opposed faces (i. e., the opposite edge faces) pre
lower barrel portion I2, against giving or spread
sented by the body of the feed tube I5 between
ing as a result of repeated removal and replace
ment of the upper barrel portion I I on the operat 25 successive turns of the helical slot. As a result,
the lugs 42 may be formed to ride more or less
ing sleeve 28 during use of the pencil.
loosely in the helical slot for smooth and easy
Internally the operating sleeve 28 is fitted with
feeding movement and yet be associated with the
spacing members 34 which are disposed as shown
feed tube I5 so that all objectionable end play is
in Figs. l, 2, and 3 to support the feed tube I5 in
alignment with the operating sleeve 28. These 30 avoided.
A further feature of this arrangement of the
spacing members 34 also serve as partitions form
ejector pin I8 is that between the spaced lugs 42
ing compartments adapted to receive reserve leads
the lateral projection 43 is formed to extend
35, and an eraser 35 may be disposed in the upper
slightly from the longitudinal slot in the guide
end of the operating sleeve 28 as a closure for the
35 tube I5 to ride the interior face of the feed tube I5
reserve lead compartments.
so that the lugs 42 are prevented from projecting
The lead carrying and ejecting mechanism in
beyond the exterior face of the feed tube I5 which
corporated in the lead feed mechanism I 4 accord
would ,iam the lead feed mechanism. Also, as the
ing to the present invention is of the same general
lugs 42 are formed with wing portions extending
type illustrated and described in U. S. Patent No.
2,362,727, issued November 14, 1944, to B, D. 40 transversely over the exterior surface of the guide
tube I6, the disposition of the lateral projection
Smith. A lead grip sleeve I7 is provided in the
43 to ride the interior surface of the feed tube I 5
present case, as in the above noted prior patent,
contains the ejector pin I8 against lateral shifting
to grip and position a lead 31 for feeding by the
and thus additionally stabilizes the operation of
lead feed mechanism I4. The grip sleeve I'I is
the lead feed mechanism.
formed with a recess or pocket defined by a lateral
Smooth operating characteristics are also ob
flange 38 (compare Fig. 5) proportioned to receive '
tained by virtue of means employed according
a lug 39 on the associated ejector pin I8, and to
to the present invention for assembling the lead
ride with the lug 39 in the longitudinal slot in the
feed mechanism as a unit. This means, which
guide tube I6 so that the grip sleeve Il and ejector
pin I8 are retained in proper spaced relation dur- l. is illustrated best in Fig. 8 of the drawing, com
ing normal feeding movement. The longitudinal
prises a relatively thin, flexible, metallic washer
slot in the guide tube I6 is relieved near its lower
end as shown at 4B in Fig. 4 to provide clearance
for turning movement of the lateral fiange 38 so
that the grip sleeve Il' may rotate upon substantial exhaustion of the lead 37 to bring the lug 39
into alignment with a slot 4I in grip sleeve I'I
and thus allow downward movement of the ejector
pin I8 in the grip sleeve I'I to eject the exhausted
lead as illustrated in Fig. 4. Reference is made to
the above noted prior Patent No. 2,362,727 for
further details of the arrangement and operation
44 fitted over the upper exœnding end of the
guide tube I5 and resting on the end face ofv the
feed tube I5, a fiber washer 45 superimposed on
the flexible washer 44, and a second, relatively
rigid, metallic washer 46 superimposed on the
fiber washer 45. Upon assembly of the lead feed:
mechanism, ears 4'! are struck out in the guide
tube I5 adjacent the longitudinal slot and a dim
ple or boss 48 is formed diametrically opposite`
of the lead carrying and ejecting mechanism in
end face of the feed tube I5. Under this pres
sure the flexible washer 44 is flexed into the
opening of the helical slot in the end face of the
feed tube I5 which causes the flexible washer 44
to rotate with the feed tube I5 and thus insures
metal on fiber friction between the flexible wash
er 45 and the fiber washer 45 during operation
of the lead feed mechanism.
The present invention has been illustrated and
this manner.
Feeding movement of the lead carrying and
ejecting mechanism results from engagement of
the helical slot in the feed tube I5 by the ejector
pin I8, and the lead carrying and ejecting mecha
nism employed according to present invention
differs over the one disclosed in the above prior
Patent No. 2,362,727 principally in the improved
arrangement by which the ejector pin I8 is
adapted for engaging the feed tube I5. Ejector
pins used in the lead feed mechanisms of mechani-.
cal pencils are commonly formed with a lug dis.
the longitudinal slot for retaining the superim
posed washers 42, 45, and 46 pressed against the
described above in connection with a preferred
embodiment in which the features of the in
vention are particularly well suited for use. How
ever, it will .be recognized that these features are
5
amava?
alsoua'dapted for gener-'al use-otherwiseï'in» me
cha'nical pencil constructions, and such general
application of the invention is'contemplated by
the. appended- claims.
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claim:
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>l». IÍn a mechanical Apencil having va'lead feed
mechanism includingahelically-slotted feed tube
of uniform pitch throughout its length and a
longitudinally slotted guid‘e‘tube disposed >for rel
said feed tube, a ñber washer superimposed on
saidnexible washer, and a relatively> rigidme
tallic washer superimposed on said fiber washer,
said guidetube having. positioning` means at its
extending" end for retaining said -washers pressed
against the end face of said feed tube, whereby
said >.flexible washer is flexed into the opening
-of the helical slot in the endgfa-ce of said feedftube
thereby causing said- -flexible washer Ato- rotate
ative rotation inside said feed-tube, a lead'carrier '-10 with said> feed tube and insuring -metal 'on ñber
adapted for longitudinal displacement in said
friction between said flexible-»washer and said
guide tube and an associated ejector pin formed
fiber washer during operation of said lead feed
with spaced lugs, said lugs being formed to ex
mechanism.
tend through the longitudinal slot in said guide
5. A mechanical pencil comprising a hollow
tube for desposition in the helical slot in said feed
plastic barrel having separate upper and lower
tube and being spaced to ride the opposite edge
portions, a lead feed mechanism including a heli
faces presented by the body of said feed tube be
cally slotted feed tube and a longitudinally
tween successive turns of said helical slot, and said
slotted guide tube, said guide tube being fixed in
ejector pin having a lateral projection extend
the lower portion of said barrel, and said feed
ing between said lugs and disposed in the longi 20 tube being assembled in telescoped relation for
tudinal slot in said guide tube to ride the in
rotation on said guide tube, and an operating
terior face of said feed tube and thereby prevent
sleeve associated with said feed tube and extend
said lugs from projecting beyond the exterior
ing from the lower portion of said barrel for fric
face of said feed tube.
tional contact with the upper portion of said
2. In a mechanical pencil having a lead feed
barrel, said operating sleeve having an expanded
mechanism including a helically slotted feed tube
portion positioned at the joint between the upper
of uniform pitch throughout its length and a
and lower portions of said barrel for aligning said
longitudinally slotted guide tube disposed for
barrel portions at this point.
relative rotation inside said feed tube, a lead car
6. A mechanical pencil comprising a hollow
rier adapted for longitudinal displacement in said 30 plastic barrel having separate upper and lower
guide tube and an associated ejector pin formed
portions, a lead feed mechanism including a heli
with a lateral projection disposed in the longi
cally slotted feed tube and a longitudinally slot
tudinal slot in said guide tube and having spaced
ted guide tube spaced concentrically in said bar
lugs formed on said projection, said lugs being
rel, said guide tube being fixed in the lower
formed for disposition in the helical slot in said
portion of said barrel, and said feed tube being
feed tube and being spaced to ride the opposite
assembled in telescoped relation for rotation on
edge faces presented by the body of said feed
said guide tube, an operating sleeve ñtted snugly
tube between successive turns of said helical slot,
in the lower portion of said barrel, but free for
and said lateral projection being formed to ride
rotation in said lower portion, and extending for
the interior face of said feed tube and thereby 40 frictional contact with the upper portion of said
prevent said lugs from projecting beyond the ex
barrel, said operating sleeve being contracted at
terior face of said feed tube.
the end fitted in the lower portion of said barrel
3. In a mechanical pencil having a lead feed
to grip said feed tube, and spacing members dis
mechanism including a helically slotted feed tube
posed in said operating sleeve for aligning said
of uniform pitch throughout its length and a
feed tube.
longitudinally slotted guide tube disposed for rel
’7. A mechanical pencil comprising a hollow
ative rotation inside said feed tube, a lead car
plastic barrel having separate upper and lower
rier adapted for longitudinal displacement in said
portions, a lead feed mechanism including a heli
guide tube and an associated ejector pin formed
cally slotted feed tube and a longitudinally
with a lateral projection disposed in the longi- .
slotted guide tube assembled in telescoped rela
tudinal slot in said guide tube and extending
tion, a mounting sleeve fixed on said guide tube
slightly from said slot to ride the interior face
and in the lower portion of said barrel for secur
of said feed tube, and spaced lugs formed on
ing said guide tube relative to said barrel portion,
the extending edge of said lateral projection, said
an operating sleeve fixed to said feed tube and
lugs being formed with wing portions extending ,. extending from the lower portion of said barrel
transversely over the exterior surface of said
for frictional contact with the upper portion of
guide tube and oriented at an angle for disposi
said barrel, said operating sleeve having an ex
panded portion positioned at the joint between
tion in the helical slot in said feed tube, and said
lugs being spaced to ride the opposite edge faces
the upper and lower portions of said barrel for
presented by the body of said feed tube between 60 aligning said barrel portions at this point, and
successive turns of said helical slot.
said mounting sleeve having an externally
threaded portion extending from the writing end
4. A mechanical pencil comprising a barrel
having a lower portion and an upper portion, a
of said lower barrel portion, and a metal tip
lead feed mechanism including a helically slotted
member internally threaded for assembly on the
feed tube and a longitudinally slotted guide tube, 1 extending threaded portion of said mounting
said guide tube being ñxed at one end in the
sleeve, the writing end of said barrel being shoul
lower portion of said barrel, and said feed tube
dered, and said tip member being formed with a
being assembled in telescoped relation for ro
flange adapted to seat externally on said shoul
tation on said guide tube, means adapting said
der and thereby align the barrel with said tip
feed tube for rotation by the upper portion of 70 member.
said barrel, and means disposed at the extending
HERBERT W. SAMS.
end of said guide tube for retaining said feed
tube in assembled relation comprising a rela
tively thin, flexible, metallic washer ñtted over
said guide tube and resting on the end face of
75
(References on following page)
2,564,727
REFERENCES CITED
Number
The following references areof record in the
file of this
`UNITED
patent: STATES PATENTS
Number
Name
¿110551
v5
Date
1,900,669
Sheaffer et a1 ______ __ Mar. '7, 1933
2,009,182
2,028,380
Kahn ____________ __ July 23, 1935
Deli _____________ __ Jan. 21, 1936
2,030,025
Davis _____________ __ Feb. 4, 1936 1o
2,095,091
Back _____________ __ Oct. 5, 1937
211813522
2,489,714
8
Name
FOREIGN PATENTS
Number
412,376
Date
Friedlein _________ __ Mar. 8,
Stenerson _______ __ May 16,
Schaefer _________ __ June 27,
Keeran __________ __ Nov. 28,
Lynn ____________ __ Nov. 29,
Country
1938
1939
1939
1939
1949
'
Date
Great'l Britain ____ -_ June 28, 1934