Note: Descriptions are shown in the official language in which they were submitted.
DoGket M-3g5 ~1-
SELECTIYE PRINTING ~PPARATUS
~ack~round of the Invention
Field of tha Inventio~
This invention relates to the art of selective printing
apparatus.
Brief Description of the Prior Art
Variou~ prior art UOS. patents Nos. 3,330~207 to De ~an
dated July 11, 1967; 3,886,862 ~o ~amisch, Jr. dated June 3, 1975;
3,908,543 to Wirth dated September 30, 1975 3,968,745 to Hamisch,
Jr. dated ~uly 13, 1976; 3,972,281 to Sams dated August 3, 1976,
~nd 4,055,118 to Yo Sato dated October 25, 1977; and W~st Garman
Offenlegungsschrift 2,350,537 are made of record.
The invention includes an improved, compact, low cost
print head. The print head is simpl~ to construct~ requiring
relatively few parts, and yet the invention accomplishas effective
detenting of a selector ~haft of the selector mechanism in s~ite
of a gear drive between the selector sha~t and wheels which the
selector shaft drives~ According to a specific embodimant of
the invention, the selector mechanism cooperates with a series of
wheels. In the illustrated em~odiment, each wheel has a printing
member wrapped about its periphery7 and each prin~ing member has
a series of differen~ printing elements. The printing membPrs
are thus considered to be coupled to the respective wheels~ but
as far a~ the selector mechanism i~ concerned, each wheel could
be coupled to a printing member by having the wheels and printing
~ 3
Docket M 395 -2-
member~ baing one-piece, eOg., a one-piece type wheel a~ in
U.S~ patent 3,908,543, or each wheel could ~e coupled to a
printing m~mber in ~he form of a pxinting band which is trained
about the wheel and a fixed or movable support as in U~S. patents
3,S86,862 and 3~968,745 and West 5erman O~f~nlegungs~chrift
23 50 537. In ~he illustrated embodiment, the selector sha~t,
which is bnth shiftable and ro~atable, is engageable with any
selected wheel. The deten~ mechanism for the ~elector shaft
includes a slidably mounted yieldable detent member which can
10 hold the selector ~hat in any selected p~sition~ and there is
a rotary connection between the detent member and the selector
shaftO Thus, the selector sha~t moves the detent member and yet
the selector sha~t is rotatable relative to the detent member.
It is another fea ure of the invention to provide a slide which
helps suppoxt the selector ~haftO Thi~ slide perform-~ the
additional function of mounting the de ent member. The selector
shaft is preferably al80 supported at anot~er location ~paced from
the ~lide. In addition to the~e features, the detent member is
cooperable with the wh~els with which the select~r shaft
20 engages. Detenting directly on the wheels enables wheels
of any selected width or widths to be u~ed without using a
different detent member or selector shaftO The illustrated
embodiment utilizes a gear drive betwesn the selactor shaft and
the wheel~O
The invention also includ~s an arrangement for visually
indicating the indicia to be printed even though the print head
i8 movably mounted with r~spect to an indicator~ The pxint head
move~ between pxinting and non-printing po~itions and th~re is
a connector between the print head and~ the indicator that allows
30 such movement. According to an illustratîve embodiment, the~e i~
a lost-motion connection between the ~elector shaft and the
indicator~ ~he illus~ra~d connection is made by telescoping
member~. The indicator is shiftable in a stationary frame while
the selector i~ both shitable and rota~able.
In accordance with another feature o ths invention,
there i8 provided both an improved print wheel and an improved
read wheel or a print headO These wheels have the ~eature of
a gnerally annular ~ase and a printing member received about
4L3
Docket M-395 3~
the basa. The bas~ is provided with ~eparate sockets and the
marginal end~ of the band has lugs which complement the sockets.
The one ocket and it~ complementary lug are dissimilar fro~ the
othex soc~et and ~he lug which is complementary with the other
socket. In this way the band can be connected to the wheel only
one way~ The wheel has means for orienting each wheel wlth respect
to another similar wheel.
The invention also includes method of making the print
head of the inven~ioni
10 Brief Description of ~he Drawin~
FIGURE 1 is a partly exploded perspective view of a
print head assembly in accordance with the invention,
FIGURE 2 is a sectional view of the assembled print
head of the print head assembly;
FIGUR~ 3 is a sectional view taken generally along
line 3--3 of FIGURE 2;
FIGURE 4 i~ a sectional view taken generally along line
4--4 of FIGURE 2~
FIGURE 5 is a sectional view taken generally along line
20 5--5 of FIGURE 2;
FIGU~E 6 is a top plan view taken along line 6--6 of
FIGUR~ 5;
FI~URE 7 is a fragmentary sectional view of a print
wheel;
FIGURE 8 is a fragmentary sectional view of a read
wheel;
FIGURE 9 is a perspective view ~h~wing a fragmentary
portion of a selector shaft and an associated slide and yieldable
detent member î
FIGURE 10, which appears on sheet 1, shows tha print
wheel with one o~ the pxinting elements ~n a printing position
adjacent the platen; and
FIGURE 11 is a perspective view of a fixture.
Detailed Description of the Preferred ~mbodiment
Referring initially to PIGUR~ 1, there is shown a print
head a~sembly g~nerally indicated at 20 which includes a print
head 21 and an indicator mechanism generally indicated at 22,
The print head 21 is ~hown to include a pair of side plates
~ 3
Docket M~395 4
23 and 24 connected by posts 25, 2~ and 27. Threaded fasteners
28 are received by tha respectiYe posts 25, 26 and 27 and one
of the fasteners 28 i8 threadably received by a support
generally indicated at 29. The post~ 25, 26 and ~7 and the
~uppoxt 29 are ~hus securely connected to the side plates 23
and 24 by the fasteners 28. The pr~nt head 21 includes a
printing section 30 and a readin~ ~ection 31. Th~ printing
section includes a ~eries of wheels 32 rotatably mounted on
thQ support 29 as best shown in FIGURE 2. In the illustrated
embodiment, each wh~el 32 includes a base 32' (FIGVRE 7) about
the periphery of which a printing member 33 is wrappedq The
printing band 33 is shown to hav~ a series of different printing
elements 34 so that, for example, character~ 0 to 9 ana one or
more ~y~bol~ can be prin~ed3 The base 32' has a pair of narrow
gaps 3~ and 36. The gap 35 opens to the periphery of the base
32' and to a socXat 37 and the gap 36 opens to the periphery of
the base 329 and to a socket 38. Marginal end portions 39 and
40 of the printing m~mber 33 are received in the respective gaps 35
and 36, and lugs 41 and 42 are received in respective sockets
37 and 38. The entries to the socket~ 37 and 38 are ~eveled as
shown at 43 and 44 for ease of the insertion of the lugs 41 and
42. The lugs 41 and 42 are considerably wider than the respec-
tive gaps 35 and 36 so that ~he lugs 41 and 42 are captivP in
the sockets 37 ana 38. The printing members 33 are under
slight tension so that they are held securely on their respective
bases 32'.
The wheels 3~ are ~electively settable. The ~election
is accomplished by a selector ox selactor mechanism generally
indicated at 45 (PIGU~E 1) which includes a selector shaft 46
30 which carries a gear 47 and a manually engageable knob 48 suitably
secured thereto as by a threaded fastener ~9. The support 29
has an opening or aperature 50 which provides a surface for
rotatably supporting the selector sha~t 46. The support 29
includes a guideway or slideway 51 which is shown to extend
in the lengthwise direction parallel to the axis o~ the
wheels 32. The axis of the selector shaft 46 is also parallel
3C~43
Doc~et M 395 ~5~
to the axis o~ the wheel~ 32. The slideway 51 is ~hown to
slidably mount a slide 52. The slide 52 mount~ a yieldabl~
det~nt member 53. The detent member 53 has a yieldable arm 53'
(~IGURES 3 and 9~ and a detent tooth 54~ A generally central
hole 55 in each wheel 32 is defined by an internal gear 56.
The internal gear 56 has beveled side edges 57 into which the
tooth 54 of the detent member 53 can move. The tooth 54 1~
shown in FIGUR~ 3 to ~e detented between adjacent wheels 32 and
the gear 47 is shown to be in mesh with a gear 56 of one of the
o wheels 32. ~y rotating the selector shaft 4S, the wheel gear 56
with which the gear 47 iq engaged is driven to bring a different
printing element 34 to the printing position P ad~acent a platen
58 to print on an in ervening record R, The salector shaft 46 can
be shi~ted by either pushing or pulling on the knob 48 to bring
the gear 47 into meshing engagement with any one of the other
wheel gears 56. The detent member 53 and the slide 52 are
connected to the seleotor shaft 46 as bes~ shown with reference
to FIGUR~S 3 and 9. The selector shaft 46 has an outwardly
converging head 59 which merges with a reduced portion 60. The
20 reduced portion 60 is disposed between the head 59 and the g~ar
47 as shown in FIGURE 3. The end of the head 59 adjacent the
reduced portion 60 provides a shoulder 61~ A socket 62 which is
connected to the slide 52 and the detent member 53 provides a
rotary connection with the selector ~haft 460 The socket 62 has
an inwardly exgending projec~ion with opposed shoulders 64 and
65. The shoulder 64 abuts the shoulder 61 and the shoulder 65
abuts the side of ~he gear 47~ Thus, the socket 62 is captive
between the shoulder 61 and the gear 47 so that the slide 52 and
the detent msmber 53 move together with the selector ~ha~t 46
30 whenever tha salector shaft 46 i5 ~hifted~ ~loreover, the
projection 62 is generally annular as is the outer surface of
the reduced portion 60 and thus the selector shaft 46 can
rotate relative ~o the slide 52 and to the detent member 53.
The socket 62 is shown to be split to ~nable insertion of the
head 59 to the position shown in FIGURE 3.
~ lthough the selector mechanism 45 is ~hown to be used
in conjunctlon with wheel~ that print~ this ~elector mechanism
45 could also be u~ed in conjunction with wheels that drive
4~
Docket M-395 6
print ~ands about a support as in U.S. patent 3,968,745 or
in conj~nction with wheels that drive print wheels~ for
exampleO
~ 'he wheels 32 are shown to be detented in any
selected position by a detent mechanism generally lndica~ed at
66r ~he support 29 al50 includes a recess 67 which extends in ~he
lengthw~se direction paxallel to the axis o~ the wheels 32. The
recess 67 is shown to open to the outer periphery of the support
~9. The recess 67 receiv~s a dstent member in the form of a
o helical spring 68. The spring 68 i~ preerably of one~piece
constxuction so that it contacts and is common to all the wheel~
32. The recess 67 is contoured so that the spring 68 is
contacted and supported in the recess at four locations 69,
70~ 71 and 72 and extends beyond the periphery of the support 29.
The spring 68 is essentially non-deformable, whareas the wheels
32 deform resiliently when indexed. The turns of the spring 68
are tightly wound as be~t shown in FIGURE 3 and preferably the
spring 68 is composed of metal, specifically small diameter wire.
The wire diameter is less than the thickness o a wheel 32.
20 The bases 32' of the wheels 32 are composed of plastics
material which i-~ resiliently deformable when a wheel 32 is
indexed~ The internal gear 56 has teeth 73 defined by pairs
of converging suxfaces 74. In a detented position as shown
n FIGURES 7 and 10 for example, $he spring 68 is shown to be
in contact with both converging surface~ 74 of a pair. ~ach pair
of converging recesses 74 pro~ides a recessl ~hen a wheel 32 is
advancedy one pair of converging surfaces 74 leaves contact with
the spring fi8 and an adjac~nt pair of convergin~ surfaces 74 are
cammed into cooperation with the spring 68 by the spring 68 as
30 the wheel returns to its original shape.
The reading wheel sec~ion 31 is shown ~o include a series
of read wheels 75. The read wheels 75 have generally annular
~ases 76 about which band~ 77 are wrapped. The bands 77 have
human readahle indicia 78 corresponding to the printing elements
34 on the wheels 32. The base 76 ~FIGURE 8) of each wheel 75 has
a pair of sockets 79 and 80 for receiving respective lugs 81 and
82. A narrow gap 83 opens into the socket 79 and to the outer
periphery of the base 76 and a narrow gap 84 opens into the
~ocket 80 and into the outer periphery of the base 76~ The
Docket M-395 -7-
gap~ 83 and S4 are narrower than respecti~e lug~ 81 and 8Z ~o
that the lugs 81 and 82 are held captive in respective socke~s
79 and 80. There is a continuous bevel 85 in the side of the
base 76 adjacent the socke~s 81 and 82 and the gaps 83 and 84
to acilitate insertion of ~he lugs 81 and 82. The bases 76
are shown to be rotatably mounted on a post or shaft 86~ A
gear 87 is connected to each wheel 75 and is preferably
molded integrally with the base 76. Each gear 87 meshes with
a gear 88 which i5 connected to a respective wheel 32. Th~
o gear 88 is preferably molded integrally with respective base 32'.
When the selector shaf~ 46 is rotated, the gear 88 associated
with the selected wheel 32 drives a meshing gear 87 of a
respective read wheel 75. The user can observe which prin~ing
element~ 34 are at the printing position P by looking through
transparent portions or windows 89 of respective members 90
Each member 90 has a plurality of functions. Each mamber 90
is prefexably molded from plastics material. The surface of
each member 90 is matte or non-transparen~ except .or the window
89, the ou~er surface of which is arched to provide a lens 89'.
20 The lenses 89' provide some magni~ication o~ indicia 78 on ~he
read wheels 75.
The members 90 have recesses 91 which have a depth
substantially equal o the width or thickness of the gear 87
which they guide. ~he m~mbers 90 are arranged in a stack so
that the gears 87 ara trapped between adjacent members 90.
Each member 90 has the same width (except for clearance) a~ an
associated wheel 32 and it is apparen~ that the members 90
guide the g~ars 87 for rotation in respective paths in alignment
with xespective meshing gears 88. The members 90 also serve as
30 shields to prevent damage to the gear3 87 in the event the print
head or the labeler or o~her printing apparatus of which it
forms a part should be dropped or otherwise ~bused.
While the user can visually observe the pxinting
elements which are at the printing position by peering
through the window 89, the user is informed as to the particular
wheel 32 with which the selector shaft ~6 is coupled by means
of the indicator mechanism 220 The indicator mechanism 22 is
connected to the print head 21 by a connection generally indicated
Docket M-395 -8-
at 92 which ~nahles the print head 21 to move into and out of
printing cooperation with the platen 58, while an indica~or
93 i~ only slidable relative to a fixed frame 94. The indicator
93 is slidable in a track parallel to the direction of shi~tlng
moveMant of the selector shaft 46. The indicator 93 includes
a pair o~ opposed pointers 95 which are aligned with the gear
47 o~ the selector 45 and with the respec~ive read wheel 75 at
the window 89. The print head 21 is guided for back and
orth movement by two pair~ o~ oppo~ed ball tracks 96 and 97,
o and 98 and 99. The ball tracks 97 and 99 are considered to be
part of the frame 94. Ball bearing strips lO0 and 101 are
disposed ~etween respective ball tracks 96 and 97, and 98 and
99. The connection 92 is more ~articularly a lost motion
connection. 5pecifically, ~he connection between the print
head ~1 and the indicator 93 includes a pair of telescoping
members 102 and 103. The ~ember 102 is connected to the
selector shaft 46. A tubular project.ion 104 on the knob
48 extsnds into a hole 105 in the me~ber 102. The scraw 49
extends through the knob 48 and into its tubular projection 104
20 and is threadably received hy a hole 106 in ~he selector shaft
4S. The member lD2 is ~ree to pivot on the projection 104. The
opposite sides of the member 102 are provided with guide
members or lugs 107. The indicator 93 has a depending,
essentially hollow member 108 having four spaced apart
projections lO9. The member 102 is telescopically recei~ed in
the member 108. Each g~ide member 107 slides in slidable
relation~hip be~ween two respective pairs of tha projections
109. The guide members 107 are in constant guided relationship
with the pxojections lO9 irrespective o~ whethar the print
30 head 21 is in the printing position or is in the non--printing
position in which the print head 21 i3 spaccd from the platen
58. Notwithstanding the fact ~hat the print head 21 moves
between the printiny and non-printing position~, the indicator
mechanism 22 remains coupled with the print head 21 and
in particular remains coupled with the selector shaft 46.
The sha~t 86 has an axially extending groove llO which
is shown to semi-circular, and each wheel base 76 has a groove
or opening llO' which is shown to be semi-circular. When the
grooves 110 and llO' are aligned they ~Olll. a ;~ca.i..g hole or
Docket M-395 9
opening 111. Each wheel has holes or openings 112 and 113
angularly spaced apart by other than 180~. In assembling the
print head 21, the ~upport ~9 ~s connected to tha side plate 23
by a ~crew 28. When the support 29 i~ connected to the side
plate 23, arcuate projection 50~, which partially surrounds the
axis of the hole 50, fits snugly into a hole 23' in the side
plate 23. Thereupon9 side plate 23 is placed in a fixture F with
pins A9 B and C sticking through respective holes or openin~s
111', 112' and 113' in the side pl~e 23. The side plate 24 also
lo has corresponding aligned holes 111', 112' and 113'. A whael 32
and a corresponding read wheel 75 are assembled in pairs onto
respective suppor s 29 and 86~ The wheels 32 and 75 can only be
a~sembled one way becau~e of the pins A, B and C. Specifically
the pin A extends through the holes 111 ~ in side plate 23) and
111~ the pin B extends through holes 112' and 112, and pin C
extends through holes 113 ' and 113 . As indicated above, the
printing members 33 can only be assembled onto the respective
wheels 32 one way, and the bands 77 can only be assembled onto
the respec ive bases 76 one way. Each wheel 7S could be provided
20 with an additional aligning hole disposed at an angular position
of other than 180~ from the notch 110 ' but the same result can be
obtained by obserYing that each gear 88 must be spaced from he
adjacent gear or gears. Thus, if two gears 88 are in face-to
face contact, then one of contacting gears 88 is turned the wron~
way. ~hen all the wheels 32 and 75 are properly ali~ned~ the
readable indicia 34 are all in a straight row showing blanks and
the blank positions of labels 32 are at the printing position as
shown in PIGU~E 2 for example. ~hen all the wheels 32 and 75 are
assembled, the selector sha~t 46, coupled ~o the ~lide 52 and to
30 the dPtent member 53, is inserted into the space within the
wheels 32 with its end portion 46' exten~ing a short distance
through hole 23'. ~hen ~hus positioning the selec~or shaf~ 46~
the slide 52 is inserted through the end of the slideway 51~ In
this position of the selector shaft 46, the member 102 can be
slid o~to the projection 104 and the knob 48 can be slipped over
the end portion 46' ~o that flat 46" complemen~ a correspDnding
` f lat ~no~ shown) on the knob 48. The knob 48 is thus non~ro~atab-
ly connected to the shaft 46 and the screw 49 keeps the knob 48
from slipping of the ~haft 46. The scre~ 49 -' 3C _~ re_~_ th_
4L3
Docke~ M-395 -10-
projection 104 which i9 split to prevent the connector 102 from
shafting axially on the projection. Thereafter the side plate 24
is connec~ed to tlle side plate 23 by the rest of the screws 28.
With the exception of the metal screws 28 and 49,
the metal ~all bearing strips lO0 and lOl, the metal spring 68,
and ~he bands 33 and 77 which are composed of elastomeri~
material, the entire assembly 20 is composed of moldable plastics
material. The one-piece element which comprises thé slide 52,
the detent member 53 and the socket 62 is cons~ruct~d o~ a material
lo -that is sufficiently flexible and resilient to enable the arm 53' to
flex as the selector shaft 46 is shifted axially and to enable
th~ socket 62 to open to receive the head 59 during assembly.
Also the entire shaft 4S and the gear 47 are molded as one piece.
~ hile it is preferred to detent the selector 46 and the
wheels 32 in the space within wheels 32, in another embodim~nt
(not shown) the detenting of both the selector 46 and read wheels
75 is accomplished in the ~pace within the read wheels 750
Other embodiments and modifications of this
invention will suggest themselves to those skilled in the art,
and all such of these as come within the spirit of this invention
are included within its scope as best defined by the appended
claims.
