Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
  • B41J2/22—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material
  • B41J2/23—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material using print wires
  • B41J2/235—Print head assemblies
  • B41J2/265—Guides for print wires
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
  • B41J2/22—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material
  • B41J2/23—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material using print wires
  • B41J2/235—Print head assemblies
  • B41J2/25—Print wires
  • B41J2/255—Arrangement of the print ends of the wires
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
  • B41J2/22—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material
  • B41J2/23—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material using print wires
  • B41J2/27—Actuators for print wires
  • B41J2/275—Actuators for print wires of clapper type

Definitions

• This invention relates to wire matrix print head apparatus of the general type disclosed in prior United States Patents, Nos. 3,929,214 and 3,994,381.
• this invention comprises an improve ⁇ ment in a wire matrix print head assembly and apparatus disclosed in my co-pending United States Application Serial No. 809,423, filed June 23, 1977, the disclosure of which is hereby incorporated herein by reference.
• the present invention involves improvements in the manner of mounting and supporting the armature members.
• the invention comprises a construction and arrangement wherein radially intermediate portions of the armature members are pivotally supported on the radially • innermost magnetic pole portions with a resilient 0-ring member located opposite thereto and continuously engaging each armature member.
• Each of the radially innermost pole portions are positively uniformly located and positioned relative to the O-ring member by abutting engagement with the portion of the armature housing supporting the O-ring member.
• the radially innermost portions of the armature members are engageable with an adjacent continuous annular side' surface of a resilient locating ring member in the non-print position.
• Adjustment and locating means are pro ⁇ vided to uniformly axially adjust the location and position of the resilient locating ring member relative to the innermost portions of the armature members to thereby uni- . formly axially adjust the location and position of each armature member relative to the wire print members, which are driven by the radially innermost end portions of the
• This invention also relates to new and improved guide and bearing apparatus for enabling assembly of wire print members by continuous uninterrupted axial movement relative to the guide and bearing apparatus and for enabl ing accurate reliable reciprocable operation after assemb of the wire print members on accurately located and posi ⁇ tioned multiple bearing means portions of the guide and bearing apparatus with the print end portions of the wire members arranged in accurate relatively closely spaced juxtaposition.
• the bearing apparatus of prior wire matrix print head assemblies of the type disclosed in my prior U.S. Patents Nos. 3,939,214; 3,994,381 and 4,051,941 has comprised a pair of axially spaced relatively narrow width intermediate wire support members located in widely axially spaced relationship between an armature end passa and a print end passage in a wire housing portion of the assembly,.
• the conventional assembly procedure involves the use of special thin tweezers to grip and loca the end of the wire members relative to and prior to being received in each passage after the first armature end pass ⁇ age resulting in interrupted, discontinuous axial movement of the wire members.
• One prior attempt to solve these problems has in ⁇ volved the use of a continuous straw-like tube for each wire member having a constant diameter substantially in excess of the diameter of the wire member with the tube being mounted in a flexible bowed condition between the end passages.
• the present invention involves the provision and use of relatively low cost, easily assembled, durable wire bearing means in a wire matrix print head assembly which enables assembly of the wire members by con ⁇ tinuous uninterrupted axially directed assembly movement while also providing for accurate bearing support of the wire members at proper positions and locations therealong in the assembled position resulting in improved performance in use.
• the bearing means comprises one or two elongated interconnectable separate bearing members, each being made of one piece of molded plastic material having a plurality of axially align ⁇ ed wire passages which, upon assembly and interconnection of the separate bearing members, provide relatively short length accurately axially spaced bearing means passage portions in a continuous elongated wire guide passage enabl ⁇ ing assembly insertion of the wire members by continuous un ⁇ interrupted axial movement therealong.
• FIG. 1 is a schematic side elevational view of a wire matrix print head assembly
• Fig. 2 is an enlarged cross-sectional side eleva ⁇ tional view of a portion of the assembly of Fig. 1;
• Fig. 3 is an end view of the print end of the apparatus of Fig. 2;
• Fig. 4 is an enlarged partial bottom view of the apparatus of Fig. 1;
• Fig. 5 is an ,enlarged cross-sectional side eleva ⁇ tional view of the central bearing member of the assembly of Figs.. 1 and 2 taken along line 5-5 in Fig. 6;
• Fig. 5a is another partial cross-sectional view of the central bearing member
• Fig. 6 is an end view of the bearing member of Fig. 5 taken in the direction of the arrow 6 in Fig. 5;
• Fig. 7 is another end view of the bearing member of Fig. 5 taken in the direction of the arrow 7 in Fig. 5;
• Fig. 8 is an enlarged side elevational view of the end bearing member of the assembly of Figs. 1 and 2;
• Fig. 9 is a bottom view of the end bearing member of Fig. 8.
• Fig. 10 is an end view of the end bearing member of Fig. 8 taken in the direction of the arrow 10 in Fig. 8;
• Fig. 11 is another end view of the end bearing mem ⁇ ber of Fig. 8 taken in the direction of the arrow 11 in Fig. 8
• Fig. 12 is an end view, partially in cross-section of an illustrative embodiment of a matrix print head assembly
• Fig. 12a is a partial end view of a portion of the apparatus of Fig. 12;
• Fig. 13 is a partial side elevational view in cross-section of the assembly of Fig. 12;
• Fig. 14 is a partial side elevational view in cross-section of a presently preferred embodiment of a matrix
• Fig. 15 is a partial end view, partially in cross- section, of the apparatus of Fig. 14.
• the apparatus as shown in Fig. 1 com ⁇ prises a wire matrix print head assembly 20 having an arma ⁇ ture housing portion 22 and a wire guide housing portion 24 extending axially outward along a central longitudinal axis
• the wire guide housing portion 24 comprises a pair of generally parallel spaced flange wall portions 30, 31 connected by a transverse web wall portion 33 to define a generally rect ⁇ angular cavity 34 between side surfaces 35, 36, 37., 38, 39.
• a rectangular slot means 44 extends through end wall portion
• a central wire guide and bear- ing means member 52 is received in cavity 34 and supported by wall portions 30, 31, 32.
• Each of a plurality of wire print members 54 are freely reciprocably slidably mounted in one of a corresponding number of separate continuous un ⁇ interrupted guide and bearing passage means 56, 57, 58, 59, 60, 61, 62, 63, 64 provided by aligned passage portions in the front end and central guide and bearing means members 50, 52.
• the rear drive end portions 65 of the print wire members are mounted in guide and bearing passage means 66 in a flange portion 67 of the armature housing means 22.
• there are nine such wire members and nine guide and bearing passage means there are nine such wire members and nine guide and bearing passage means.
• the number of wires and corresponding guide and bearing passage means therefore may be varied as necessary or desirable including special arrangements arranged to print solid line characters which may be optically scanned by known optical carrier recognition apparatus.
• Conventional drive head means 68 are mounted on the rear drive end wire portions 65 for operative engagement with armature members 69 operable by electrical coil means 72 as described in prior U.S. Application, Serial No. 809,423, filed June 3, 1977, the disclosure of which is in corporated herein by reference.
• the armature housing portion 22 and wire guide portion 24, the front end wire bearing means member 50, and the central wire bearing mean member 52 are preferably made of one piece of suitable molded plastic material such as a composite of 30% carbon fibers, 13% polytetrafluoroethylene and 2% silicon in nylo
• the central guide an bearing means member 52 comprises an elongated rearwardmos cylindrical portion 80, located next adjacent the side wal 38, a central rectangular support flange portion 82, and a forwardmost elongated generally rectangular grooved portio 84 extending toward the front bearing means member 50.
• Th member 52 is suitably fixedly mounted in the cavity 34 wit the upper peripheral surface 85 of the cylindrical portion 80 engaging the adjacent portion of inner surface 37 of th web portion 33 and the peripheral surfaces 85, 86, 87 of the flange portion 82 engaging, respectively, the web surface 37 and retaining slots (not shown) along the inner flange surfaces 35, 36 of the housing portion 24.
• the portion 84 is supported in forwardly extending cantilever fashion from flange portion 82 and is laterally inwardly spaced from the side walls and web portion of cavity 34.
• the wire passage portions of each of the wire guide and bearing means passages 56-64 provided i the member 52 comprise a first relatively long guide means passage portion 90 of generally triangular cross-sectional configuration which is gradually reduced in cross-sectiona area between an inlet opening 92 and. a circular outlet opening 94; a relatively short length bearing means passag portion 96 of uniform circular cross-section having an inlet opening which is the same as the outlet opening 94 and an outlet opening 98; and a relatively long length gui and bearing groove passage portion 100 of generally tri ⁇ angular cross-sectional configuration connected at one end to outlet passage 98 and terminating at the other end in outlet bearing openings 102.
• Each wire guide means passage portion 90 comprises an elongated radially innermost arcuate guide surface 110 with centers of curvature located at 112, 113, 114, 115, 116, 117, 118, 119, 120, Fig. 7, and having a radius of curvature slightly larger than the radius of the wire members 54.
• Guide surfaces 110 extend in parallel linear relationship with one another and the central longitudinal axis 25.
• Each passage portion 90 further comprises a pair of circumferen- tially -spaced generally radially outwardly extending flat side surfaces 124, 126 tangentially connected by curved inner surfaces 110 and an arcuate radially outermost surface 128 having a center of curvature along the central longi ⁇ tudinal axis 25.
• the equally spaced centers of curvature 112-120 are arranged in a generally elliptical pattern at varying radial distances from the central longitudinal axis 25. .
• the circumferential and radial location as well as the cross-sectional areas of the passage portions 90 may be varied as necessary or desirable to accommodate the number of wire members used in any particular embodiment.
• Each bearing means passage portion 96 has a uni- form circular cross-sectional configuration with a radius of curvature equal to and coaxial with the radius of curva ⁇ ture of the arcuate inner surfaces 110 of the guide means passage portions 90 so that the radially innermost surface portions of the circular passage portion 90 are coplanar with the arcuate inner surfaces 110 and arranged in the same generally eliptical pattern as the centers of curva ⁇ ture 112-120.
• the diameter of bearing means passage portions 96 are slightly larger than the diameter of the wire members.54 to enable free sliding movement there- through while providing confining circumferential bearing support therefor.
• the diameter of bearing passage portion 96 is preferably .016 inch and the length is approximately .03 inch.
• Each guide and bearing groove passage portion 100 comprises an elongated radially innermost arcuate guide surface 140 having a radius of curvature (the same as surfaces 110) slightly larger than the radius of the wire members 54 and a pair of outwardly diverging side surfaces 142, 144 extending tangentially from the arcuate inner surface 140.
• the cross- sectional configurations and locations of the groove pass age portions 100 relative to the central longitudinal axi are varied for the purpose of locating the print end por ⁇ tions of the wire members in a predetermined pattern at the outlet openings 102 whereat, as shown in Fig.
• the centers of curvature of the arcuate inner surfaces 140 of the groove passage portions 100 of the guide and bearing passage means 56-64 are located in coplanar relationship in two parallel planes represented by lines 146, 148. with five of the centers of curvature located in plane 146, on " one side of and closely adjacent to the central axis 25, and four of the centers of curvature located in plane 148 oh the other side of and closely adjacent to the central axis 25. Also, as shown in Fig. 6, by the transverse center lines 150, the centers of curvature are equally laterally offset from one another in laterally staggered relationship with adjacent centers of curvature being loc ed in relatively closely spaced lateral relationship.
• the inner surfaces 140 of th groove passage portions 100 of the laterally opposite gui and bearing passage means 56, 60 extend parallel to the central longitudinal axis 25 throughout their length as shown in Fig. 5 while the inner surfaces 140 of the other groove passage portions of the guide and bearing passage means 57, 58, 59, 61, 62, 63, 64 have first inwardly tape ed portions 152 of variable length next adjacent the open ings 98 and second portions 154 of variable length next adjacent openings 102, Fig. 5a, which also extend paralle to the central longitudinal axis 25 and the inner surfaces 140 of the groove passage portions 100 of the passage means 56, 60.
• An end portion 160 of reduced uniform rectangular cross-sectional configuration which may serve as a connect ⁇ ing plug, is provided at the end of the cantilever portion 84 of member 56 with the outlet openings 102 spaced along the periphery thereof and with a transverse abutment surface 162 to provide connecting means for connecting member 52 to member 50.
• the circular extensions of each of the curved surfaces of groove passage portions in plug portion 160 and outlet openings 102 are tangential to the associated side surfaces of the plug portion 160 so that the outer peripheral surface of eaqh wire member is locatable within the confines of the rectangle defined by those side surfaces.
• the front guide and bearing means member 50 which may or may not be used as necessary or desirable, has an elongated generally rect ⁇ angular block-like peripheral configuration defined by opposite parallel relatively narrow width upper and/or lower side surfaces 170, 172; opposite parallel relatively wide width side surfaces 174, 176; and opposite parallel end surfaces 178, 180.
• each of the wire guide and bearing means passages 56-64 provided in the member 50 comprise an elongated tapered passage portion 190 extending between an enlarged wide mouth inlet opening 192 in a transverse end wall 194 of a rectangular connecting socket portion 196 adapted to receive the connecting plug portion 160 of member 52 and a reduced generally circular very short length end bearing means passage 198 having an outlet opening in a laterally inwardly offset transverse end wall 200 of a rectangular end cavity portion 202.
• Each inlet opening 192 comprises a pair of opposite ⁇ ly facing semi-circular relatively widely spaced arcuate •
• the outer portions 214, 216 of arcuate surfaces 206, 208 of the upper and lower end inle openings 192 are tangential with socket upper and lower e surfaces 218, 220 and the inner portions 222, 224 are tangential with passage separating rib portions 226, 228 which also separate each of the interior inlet openings 19 and extend tangentially relative to the arcuate surfaces thereof.
• Each of the arcuate surfaces and separating rib portions extend the length of the passages 190 and are tapered to gradually reduce the distance between the arcu surfaces (thus reducing the cross-sectional area of each passage) between the inlet openings 192 and the end beari passages 198 while maintaining uniform height of the pass ⁇ ages 190 measured between laterally adjacent rib portions.
• end bearing passage portions 198 have diameters only very slightly larger than the wire diamete with coplanar centers of curvature located along center li 230 with adjacent passage portions being substantially tangentially located relative to one another whereby each the wire members are located in closely spaced stacked co- planar alignment along center line 230.
• Attachment means are provided along the upper a lower surfaces 174, 176 of member 50 in the form of reduc width rib portions 210, 242 formed by slots 244, 246, 248, 250.
• Each rib portion comprises a first relatively wide portion 252 having parallel side surfaces 254, 256 inter ⁇ secting transverse abutment surfaces 258, 260 adjacent th front end of member 50.
• Notch means 262, 264 are provide in each side surface 254, 256 for receiving cooperating resilient tang means in the wire housing portion 24 as he inafter described and each notch means comprises an inclined surface 266 and a transverse abutment surface 268.
• the first wide portion 252 is connected to a second relatively narrow rib portion 270 by inclined cam surfaces 272, 274.
• Mounting slot 44 includes attachment and support means provided along the side walls 280, 282, Figs. 2 and 4, in ⁇ the form of upper and lower pairs of rib portions 284, 286 extending along and inwardly from the side walls.
• Each of the rib portions comprises a transverse abutment surface 288 adapted to abut the corresponding one of surfaces 258,
• the lower pair of rib portions 284, 286, Fig. 4 have inwardly offset interlocking tang means 292 adapted to be abuttingly received in the notches 262 of the lower pair of slots 298, 250 of member 50 and include a correspondingly tapered side surface 294 and a transverse abutment surface 296 which extends outwardly to spaced parallel side"wall portions 297, 298.
• the arrangement is such that member 50 may be mounted in slot 44 with surfaces 170, 172 as upper or lower ' surfaces . Assembly of .Bearing Means Member
• the central bearing means mem- ber 52 is inserted in the enlarged rear portion of cavity 34, which has a rectangular cross-sectional configuration corre ⁇ sponding to the peripheral configuration of mounting flange portion 82 of member 52 and mounting slots (not shown) formed in the side wall portions 30, 31 to frictionally grip and retain the flange portion 82 therebetween with the upper peripheral surfaces 84, 85 abutting the inner surface 37 of the housing.
• the bearing means member 50 is slidably inserted into slot 44 through the front of end flange portion 26 of the wire housing portion 24.
• the rib portions 284, 286 of the housing portion are slidably received in the slots 244, 246, 248, 250 of the bearing member 50.
• the rib portions 270 which are of narrower width than the distance between rib portion surfaces 280, 282, are freely movable past tang portions 292. Then inclined surfaces 272, 274 on the rib portions 240, 242 of bearing means member 50 engage the oppositely -inclined surfaces 294 on the tang portions.
• member 50 Further inward movement of member 50 causes resilient com ⁇ pression of the tang portions until transverse abutment surfaces 268, 296 become aligned whereupon the housing tang portions 292 are located in the tang slot portions 264 of member 50 with abutment surfaces 268, 296 being engaged and abutment surface 288 of member 50 engaging the abutment ⁇ surfaces 288 of the housing rib portions 284, 286.
• the rear end portion of member 50 extends inwardly beyond the abutment surfaces 296 and is laterally spaced from the inner side wall surfaces of the . housing portion 24.
• the plug portion 160 of member 52 is slidably received in the socket portion 196 of member 50 with tapered surfaces 197 facilitating slidable insertion therein.
• peripheral side surfaces of plug portion 160 of member 52 and of socket portion 196 of member 50 are slidably abuttingly engageable to locate and align the passage portions therein with the peripheral side surfaces of the socket portion 196 closing the open portions of groove passage portions 100 in the plug portion 160 to pro- vide intermediate bearing means for the wire members which are laterally confined therebetween and therewithin.
• Each wire member 54 is assembled through the guide and bearing passage means 66 in the armature housing flange portion 67 prior to assembly of the armature members 69.
• the wire member print end portion is simply inserted in the passage means 66 and the wire member is pushed axially for- wardly in one continuous uninterrupted movement until the assembly movement is completed.
• each wire member extends in a straight unflex- ed condition from the drive head 68 through tapered passage 66 and is freely slidably supported and circumferentially confined by a relatively short length reduced diameter first ' 0 bearing means passage portion 302 having a diameter slight ⁇ ly larger than the wire diameter (e.g., .016 inch diameter for a .0142 inch wire diameter).
• a first innermost inter ⁇ mediate wire portion 304 between the outlet opening of bear ⁇ ing means 302 and the inlet opening of bearing means passage 5 portion 96 is mounted in a flexed bowed condition in passage portion 90 in complete circumferentially spaced relationship to the side surfaces 110, 124, 126, 128 of passage portions 90.
• a relatively short length portion of the wire member is freely slidably supported and fully circumferentially con- 0 fined by the reduced diameter second bearing means passage portion 96 having a diameter slightly greater than the wire diameter.
• a second outermost intermediate wire portion 306 between bearing passage portion 96 and bearing passage por ⁇ tion 300 is supported in a lesser flexed bowed condition in 5 groove passage portion 100 between the outlet opening of bear ⁇ ing means passage portion 96 and the inlet opening to bearing means passage portion- 300 in circumferentially spaced rela-
• OMPI tionship to the side surfaces 140, 142, 144 of the groove passage.
• a relatively short length of the wire member is freely slidably supported and fully circumferentially con-, fined by the third bearing means passage portion 300 which has a cross-sectional configuration slightly larger than the wire diameter.
• the intermediate portions of the wire members between the outlet openings 310 of bearing passage portions 300 and -bhe inlet openings of bearing passage por tions 190 are slightly inwardly flexed and circumferential ly spaced from surfaces 205, 208 to change the wire member pattern from that of .o parallel laterally offset rows of coplanar groups o '- staggered wire members, illustrated by center line 146, 148 of Fig.
• each wire member is freely slidably supported and very closely circumferentially confined in bearing means passage portion 198 which has a diameter only very slightly greater than the wire diameter (e.g., .0145 ⁇ .0002 inch diameter for a .0142 inch diameter wire) .
• the end surfaces of the print end portions are ground to provide exact align ⁇ ment.
• the cavity 202 prevents damage to the bearing -means passage 198 during grinding and enables removal of any spu on print end portions of the wire members adjacent the end surfaces.
• each wire member is supported during re- ciprocable movement in use by four relatively short length bearing means passage portions 302, 96, 300, 198, the axial spacing and length of each set of bearing means for each wire being uniform and the axial spacing between adjacent pairs of passage portions 302 and 96, 96 and 300, and 300 and 198 being substantially equal whereby approximately equal lengths of the wire member extend between the outlet opening of bearing passage 302 and the inlet opening of bearing passage 96, between the outlet opening of bearing passage 96 and the inlet opening of bearing passage 300, an
• the bearing means 302 in armature housing means passage 66 have a diameter of .016 ⁇ .001 inch; the radius of curvature of arcuate surfaces 110 of guide means- passage portions 90 is .008 inch; the diameter of bearing means passages 96 is .016 ⁇ .001 inch; the radius of curva- ture of arcuate surfaces 140 of guide and bearing means passage portions 140 is also .016 ⁇ .001 inch; and the diameter of bearing means passage portions 198 is .0145 ⁇ .0002 inch.
• the : ' inventive concepts may be utilized in other alternative embodiments of the invention.
• a conventional ruby bearing plate or the like is mounted" in a conventional manner in a cavity-like 202 in end wall portion 26 to pro- vide bearing passage means similar to 198 with guide pass ⁇ ages provided from surface 39 in end wall 26 to the ruby bearing passage means.
• the print head apparatus comprises a housing means member 410 having an elongated wire stylus guide and support portion 412 and an annular armature housing portion 414 for supporting a plurality of elongated wire stylus print members 416 and an equal number of armature members 418 mounted in equal radially and circumferentially spaced relationship about a central longitudinal axis 420.
• the print head apparatus further comprises electromagnetic mec ⁇ ' ns comprising magnetic metallic plate means 422 for supporting an equal number of armature actuating magnetic pole means 424 and electrical wire coil means 426 located in equally radially and circumferentially spaced relation ⁇ ship about central axis 420 in juxtaposition to and opera ⁇ tive relationship with the armature members 418.
• the magnetic plate means 422 which may have a generally elliptical peripheral configuration to provide mounting means for attachment to a printer apparatus (not shown) , is secured to the housing means 410 by a fastening means 428 to define an annular chamber 430 in which are mounted the armature members 418, the magnetic pole means 424, and the coil means 426. — -
• wire styli print members 416 of conventional design each including a paper impacting end portion (not shown) and an impact head portion 434.
• the wire members 416 are slidably reciprocably movable between a retracted non-print position, lower armature of Fig. 12 and 14, and an extended print position, upper armature of Fig. 12.
• the wire members are normally located in the non-print position by associated spring members 436 and are movable to the print position by kinetic energy obtained from associated armature members 418.
• An intermediate portion 439 of each armature member is pivotally supported by the radially innermost pole portion 440 and mounted between the associat ⁇ ed magnetic pole means 424 and the housing means portion 414 so as to cause pivotal movement of the drive head portion
• the Housing Means Referring to Figs. 12 and 14, the housing means
• the 410 is preferably made of one piece of rigid molded plastic material such as glass reinforced temperature resistant nylon.
• the housing portion 414 comprises a central axially extending elongated annular hub portion 450, a radially extending annular flange portion 452 and an axially extending annular outer rim portion 45 -
• the hub portion has a central annular bore 456 for receiving fastening means 428 which may be in the form of a self-threading self-locking screw member or the bore 456 may be threaded.
• a radially innermost annular axially extending first inner rim portion 458 is radially outwardly spaced from hub portion 450 to provide an annular cavity 460 there ⁇ between in which are mounted the drive end portions 438 of the wire members 416 and spring members 436.
• An equal number of circumferentially spaced tapered wire guide bores 462 are provided in flange portion 452 and extend into cavity 460 through annular spring mounting hub portions
• compression spring member 436 is mounted circum ⁇ jacent the drive end portions of the wire members and hub portions 464 with one end of the spring member abutting a side wall surface of flange portion 452 and the other end abutting a side wall surface of a conventional plastic per ⁇ cussion cap member 434 mounted on the end of the wire mem ⁇ ber in a conventional manner.
• compression spring members 436 provide spring means for biasing the wire mem ⁇ bers 416 and the armature members toward the retracted non- print position.
• the rim portion 458 includes inner and outer axially extending annular guide surfaces 466, 468, Fig. 15", connected by a radially extending annular end surface 470, Fig. 13, to provide radially innermost armature mounting slot means circumferentially spaced thereabout for guiding and supporting the armature members during movement between the non-print and the print position.
• a radially intermediate annular axially inwardly extending second inner rim portion 472 is radially outwardly spaced from rim por ⁇ tion 458 and located in juxtaposition to another radially intermediate generally annular axially inwardly extending third rim portion 474 to provide ah annular O-ring groove 476 therebetween in which is mounted a resilient compress- ible O-ring member 478 for continuously engaging the inter ⁇ mediate portion 439 of armatures 418.
• a resilient compress- ible O-ring member 478 for continuously engaging the inter ⁇ mediate portion 439 of armatures 418.
• the rim portion 474 has a generally polygonal peripheral cpn- figuration comprising nine relatively long length circum ⁇ ferentially spaced straight sided rim portions 480 connec ed by relatively short length connecting rim portions 482
• Each rim portion 480 is centered on and extends transvers ly relative to the associated one of radial lines 484.
• E rim portion 480 provides a radially outermost second arma ture guide and support means located opposite the innermo pole portion 440 in the form of a slot 486 defined by spa parallel flat side surfaces 488, 490 extending parallel t the associated one of the radial lines 484 and a flat bot surface ' 492.
• an axially outermost cir ferentially extending slot 504 is provided between the ou rim portion 454 and the peripheral outer portion 506 of t magnetic plate member 422 to provide for full and complet access to the radially outermost ends of the armatures an for more adequate cooling of the magnetic means.
• the radially outermost pole portions 510 are provided by circumferentially spaced axi ly extending flange portions of plate member 422 having circumferentially spaced end portions 512 located opposit corresponding circumferentially spaced slots 514 in the axially circumferentially extending outer rim portion 454 housing 410 and in axiaily locating abutment with radiall and circumferentially extending side surface portions 516 with the radially outermost end portions 518 of the armat members extending radially outwardly through the slots 51 as shown in Fig. 12a.
• the plate means 422 and the pole means 424 are preferably made of one piece of sintered powder magnetic material.
• the pair of spaced parallel radially innermost and outermost pole portions 440, 493, 510 are of rectangular cross-section, as shown in Fig. 15, and integrally connected to the plate portion or separately attached thereto in any conventional manner.
• the coil member 426 is mounted on the associated pole portion 440 or 493 in axially spaced rela- tionship to the axially outermost surfaces of the pole portions.
• Each armature member 418 comprises one piece of relatively thin rigid magnetic sheet metal material having a relatively narrow width radially innermost drive head por ⁇ tion 438 with relatively closely spaced parallel side wall portions 530, 532 extending parallel to the radial lines 484.
• the spacing of side wall portions 530, 532 is slightly less than the spacing of side surfaces 466, 468 of guide slot means 486 so as to enable free sliding relative move ⁇ ment therebetween.
• a relatively wide radially outermost portion 534 is connected to portion 438 by an intermediate connecting portion 536 having inclined side wall portions 538, 540.
• Outermost portion 534 has relatively widely spaced parallel side wall portions 542, 544 extending parallel to radial line 484.
• side wall portions 542, 544 is sufficiently greater than the spacing of the adjacent side surfaces 546, 548 of the associated pole portions so as to provide a substantial surface overlap at 550, 552.
• a pair of aligned slots 554, 556 are provided along side wall por ⁇ tions 542, 544 and have a rectangular configuration such as to loosely receive the adjacent wall portions of rim portion 480 with the side surfaces of the slots 554, 556 having a spacing slightly greater than the spacing of side surfaces of guide slot means 486 so as to be received therebetween for free sliding movement relative thereto.
• the arrangement is such that in. he assembled posi-
• each armature 418 is loosely movably mounted in and laterally confined by the slot means 470 and 486 with the compression springs 436 and the O-ring member 478 cooperat ing to locate the armature members 418 in the non-print position whereat an intermediate portion of the side sur ⁇ faces 560 of the armatures are pivotally supported by the radially innermost edge surfaces 562 of the radially inner most pole portions 440 as shown in Fig. 15.
• the Inner Armature Support and Adjustment Means A radially innermost resilient annular armature support and adjustment means is provided in each embodimen for resiliently adjustably supporting the radially inner ⁇ most end portion of each armature member. In the preferre embodiment of Figs.
• a resilient annular member 570 having a flat annular armature abutment surface 572 is axially slidably mounted on the cylindrical outer peripher surface 574 of hub portion 450.
• An elongated adjustment and abutment hub member 576 has a bore portion 578 axially slidably adjustably supported on the outer periphery 574 of hub portion 450.
• An enlarged support head portion 580 axially adjustably slidably supported in a support bore 58 in plate member 422.
• An enlarged abutment head portion 58 has an abutment surface 585 extending parallel to side sur face 586 of plate member 422 with a resilient washer membe 588 compressibly mounted therebetween.
• a resilient O-ring member 590 having an annular armature abutment surface 592 is axially slidably mounted on the outer peripheral surface of hub portion 450.
• An elongated adjustment and abutment hub member 594 has a counter bore portion 596 axially slidably adjustably supported on the outer periphery of hub portion 450 and an outer peripheral portion 598 axially slidably adjustably supported in a bor portion 600 of plate member 422.
• An enlarged abutment hea portion 602 has an abutment surface 604 extending paralle to plate member surface 606 with a resilient O-ring member 608 compressibly mounted therebetween.
• a radially innermost portion of the armatures of maximum radial length extends radially inwardly beyond a first pivot means 562 provided by the edge surfaces of the radially innermost pole portion 440 and a radially outermost portion of the arma ⁇ tures of minimum radial length extends radially outwardly beyond the first pivot means.
• each of the intermediate portions of the armature mem- bers are very accurately positioned relative to the O-ring member 478 which is itself very accurately positioned by the side surfaces of annular slot 476.
• the axial location of the radially innermost end portions 438 of each armature member are adjustably very accurately uniformly controlled by engagement with the side surface of resilient members 570 or 590.
• the adjustment hub members 576 and 598 are resiliently axially floatably adjustably mounted between the resilient members 570, 588 and 590, 608.
• the magnetic force is effective on the minimum radial length radially outermost portions of the armatures to move those portions toward the pole portion end surfaces by pivotal movement about pivotal surfaces 562.
• the first pivot means provided by edge surface 612 becomes inoperative and a second pivot means pro ⁇ vided by the radially outermost edge surfaces 620, Fig. 14, or 622, Fig. 13, of the outer pole portions becomes opera ⁇ tive to sustain further pivotal movement of the armatures while at the same time increasing the radial length from the effective pivot means to the drive head portions 438 as dis ⁇ closed in my prior application.
• the O-ring member 478 is
• -arrangement is such that the return move ⁇ ment is substantially without resistance until the return movement is substantially completed. It is also to be noted that the arrangement is such that at the time of impact of the wire members 416 with the paper, the outermost pivot means 620 or 622 has been established so that maximum lever ⁇ age is utilized both during printing and during the initial part of the return movement.
• the single center connection provided by the threaded fastening means 428 between two relatively rigid accurately located parts in combination with the resilient member enables very fine accurate adjustment of the air gap between the armature members and the pole portions.

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• Impact Printers (AREA)

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• 1979
  • 1979-03-09 WO PCT/US1979/000146 patent/WO1979000738A1/en unknown
  • 1979-03-09 JP JP54500559A patent/JPH0569711B2/ja not_active Expired - Lifetime
  • 1979-03-10 DE DE19792909552 patent/DE2909552A1/de active Granted
  • 1979-03-10 DE DE2954141A patent/DE2954141C2/de not_active Expired
  • 1979-03-12 FR FR7906292A patent/FR2419166B1/fr not_active Expired
  • 1979-03-12 IT IT48312/79A patent/IT1115083B/it active
• 1990
  • 1990-10-09 JP JP2269660A patent/JPH03175053A/ja active Pending

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