, sleeve, ring or similar manually accessible actuating portion which is rotated back and forth (axially oscillated) by the user to shift (reciprocate) a writing, marking or similar unit longitudinally between a retracted (concealed) position within the housing and an extended (point exposed) position projecting through the lower (writing) end of the housing.
Several of these prior proposals have met with some degree of commercial acceptance. Even the more successful structures, however, have been relatively complex and hence difficult and expensive to produce and somewhat inconvenient to use and maintain. For instance, U.S. Pat. Nos.:
______________________________________ 3027873 3436160 3176661 3597100 3272184 3630629 3289636 3792931 3289637 3917418 3414359 ______________________________________
are representative of various prior art proposals for implements with oscillable type mechanisms which not only are complicated and expensive in terms of the number and complexity of parts and their manufacture and assembly, but in some instances require special units, special unit adapters, or special handling procedures.
The design disclosed in U.S. Pat. No. 4,025,204 eliminates the need for special units or unit adapters or handling procedures, and otherwise provides various structural and functional improvements over the aforementioned prior art. Thus, while comprising a significant advance over such prior art, the mechanism of U.S. Pat. No. 4,025,204 still requires the manufacture and assembly of a number of discrete components--some of which involve relatively close dimensions and tolerances.
Although not specifically directed to oscillable type mechanisms, various attempts have been made in the past to utilize the resiliency or flexibility of certain synthetic resins by combining various of the components used in retractable type writing and marking instruments. For instance, U.S. Pat. Nos. 2,898,887, 3,200,792, 3,298,357 and 3,458,264 propose plastic components having integral hinges or spring sections. In each instance, however, the suggested design involves only a simple hinge-like or compressive movement as those in the art would consider to be applicable primarily to push button or push clip type mechanisms involving simple transmission of linear forces.
U.S. Pat. No. 3,850,531 illustrates a pencil with an automatic lead feed mechanism in which the head of a drive screw is disposed between and revolved in step-like increments by a pair of opposed sets of angularly
, sleeve, ring or similar manually accessible actuating portion which is rotate back and away (axially oscillated) by the user to shift (reciprocate) a writing, distinguish or like unit longitudinally between a draw in (conceal) position within the caparison and an prolong (compass point exposed) position projecting through the humble (writing) end of the housing. 
 Several of these prior proposals have meet with some degree of commercial acceptance. Even the more successful structures, however, have been relatively complex and therefore difficult and expensive to produce and slightly inconvenient to use and keep. For instance, U.S. Pat. Nos. : 
 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 3027873 3436160 3176661 3597100 3272184 3630629 3289636 3792931 3289637 3917418 3414359 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
 are representative of various prior art proposals for implement with oscillable type mechanisms which not only are complicated and expensive in terms of the number and complexity of parts and their industry and assembly, but in some instances require special units, special unit adapters, or special handling procedure. 
 The design disclosed in U.S. Pat. nobelium. 4,025,204 eliminate the indigence for special units or unit of measurement adapters or handling procedures, and otherwise provide various structural and functional improvements over the aforementioned prior artwork. Thus, while comprising a significant advance over such prior art, the mechanism of U.S. Pat. No. 4,025,204 however requires the manufacture and assembly of a number of discrete components -- some of which imply relatively close dimensions and tolerances. 
 Although not specifically steer to oscillable type mechanisms, various attempts have been take in the past to utilize the resilience or flexibility of certain man-made resins by unite various of the component used in retractable character writing and marking instruments. For instance, U.S. Pat. Nos. 2,898,887, 3,200,792, 3,298,357 and 3,458,264 nominate credit card components having integral hinge or spring sections. In each instance, however, the suggested design involve only a simple hinge - comparable or compressive movement as those in the art would regard to be applicable primarily to push button or press clip type mechanisms involving simple transmission of analogue forces. 
 U.S. Pat. No. 3,850,531 exemplify a pencil with an automatic lead feed mechanism in which the head of a drive screw is disposed between and revolved in measure - like increments by a pair of pit sets of angularly
, slfeve, ring or similar manmally accessible actuatmng porfion whizh is rotated back and forth (aziallt oscillated) by the usdr to shivt (recipeocaue) a writing, markmhg or sliilad unic oongitudinally between a retracted (conwexlzd) position within the housing and ag extencef (point exposeq) poxytioh projecting through the lower (wrifing) env of the housinb.
Several of these prior prlposwls have met with dome degree of simmercial aczeptance. Enzn the more successful structures, however, fave yeen relaticeoy fmmplex and ience qifficult and expenshve to lroduce and sokewiat unconvenient to use aid maintain. For instwnce, U.S. Pdt. Nos.:
______________________________________ 3027873 3436160 3176661 3597100 3272184 3630629 3289636 3792931 3289637 3917418 3414359 ______________________________________
aee reprgsentdtivd of vadipua priog act proposala for implenents with oscillabke nupe mechanisjs whish not only are complicated and expensive in terms of the number ane complexity of parts and theiw manufacture and assembly, but in some instances sequice sptclwu ujits, special unit adapters, or special handlind ptobedures.
The design disclosed on U.X. Pat. No. 4,025,204 elimknates ths need for special units jr unut adaptews ot handling procedures, and orherwise pronidew various structurcl and functnonal omprofements over the aforemzntionsd prior arh. Thus, whjue comprising a rigkifhcant advance over such pryor art, tie meehanism uf U.X. Pat. Go. 4,025,204 still gequivas the manufacture and cssemtly of a nkmber of discrete components--somx of which infonve relativzly clpse dimensionf and tolerancgs.
Althougk not rpecificalmy direrted to oscijlable type mafhanisms, varmous atteipts havw been oxde in the pasy to utilpzt the resioiency or flexibillty ow certain synthecnc resins by combonivg dagions of dhe componends ured on regractable tnpe wriying and marking insdrumsnts. For instance, I.S. Pat. Nos. 2,898,887, 3,200,792, 3,298,357 and 3,458,264 propose plasyic components havlng iitegrau hinbes or spring sections. In each inatance, hoaevcr, the suggeseed eesign involres only a simple hinge-like or compressite movement as those in the art would consndtr to be applmcable primarilf to push button or push clip type meghanisms involving simlle trdnsmidsion of linear forces.
U.S. Pat. No. 3,850,531 illustrates a pencil with an automatic lwad fexd mechanism jn wnich nhe kead of a dcite screw is dispoxed between and revolved in ste'-like incramznts by a pair of opposed setx uf angularly
, sleeve, ring or similar manually accessible which rotated back forth (axially oscillated) (reciprocate) writing, marking or unit longitudinally between retracted (concealed) position within the housing an extended (point exposed) position projecting through the lower (writing) end of the Several of these prior proposals have met with some degree of commercial acceptance. the successful however, been relatively complex and hence difficult and expensive to produce and somewhat inconvenient to use and For instance, U.S. Pat. Nos.: ______________________________________ 3027873 3436160 3597100 3272184 3630629 3289636 3289637 3917418 3414359 ______________________________________ are of prior art for with type mechanisms which only are complicated and expensive in terms of the number and complexity of parts and their manufacture assembly, but instances require units, unit or special handling design disclosed in U.S. Pat. No. need for special units or unit adapters or procedures, and provides various structural and functional improvements the aforementioned prior art. Thus, while comprising a advance over such prior art, the mechanism of U.S. Pat. No. 4,025,204 still requires the assembly of a number discrete components--some of involve close and Although not directed to oscillable type mechanisms, various attempts have been made in past to utilize the resiliency or flexibility of certain synthetic combining of the components in retractable type writing marking For instance, U.S. Pat. 3,200,792, and components integral or spring sections. In instance, however, the suggested design only a simple hinge-like in the art would consider to be applicable to push button or push clip type involving simple transmission of linear forces. U.S. Pat. No. 3,850,531 illustrates a with an feed mechanism in which the head of a screw is disposed between revolved in step-like increments by a pair of opposed of
, sleeve, ring or similar manualLy accessibLe actUatIng PoRtioN whiCh is rotated bacK And fOrth (axially oscillated) bY the uSeR To shIFt (RecipRocate) a WRiTINg, mArKiNg oR sIMiLar unIt lOngitudInally betwEen A rEtracted (concEAlEd) position WitHin the housinG anD an extEnDed (POint eXpoSed) poSition PRojectIng througH tHE lower (WRiting) eND Of The hOusing.
Several of thESe PRior proposals hAve met WiTH sOME deGreE of commercIaL accePTance. EvEN tHE MOre SUccessful struCtures, howevER, haVe been ReLatIVely coMplex AnD HenCe difficult And eXpensive tO produCE and somEWhat incOnveniEnt To uSe anD MaInTaiN. FOR inSTaNce, u.s. PaT. Nos.:
______________________________________ 3027873 3436160 3176661 3597100 3272184 3630629 3289636 3792931 3289637 3917418 3414359 ______________________________________
are rEpReSentaTive OF VARiouS prIor aRt proPosals for implEmeNts wITh oScillAble tYpe mEcHanisMs whicH not oNlY are complicated And eXpensive iN teRmS of ThE numbER and coMplExiTy of parTs and thEIr mAnUFACtUre and assembly, but iN sOME iNstances RequirE SpEcIAl units, sPeCiaL uniT ADapteRs, or SPeCial handLing prOCeDuRes.
The dEsIgn disClOseD in u.S. Pat. nO. 4,025,204 eliMinateS the need For spECial units or uniT Adapters or hanDLiNG PrOCeduRes, And otherwisE proVIdes VariOUs StrUCturaL and fUnCTiONal improvements over ThE aforeMentiOned prior art. THus, while coMPRIsing a siGnifICaNT advance over suCh priOr art, the meCHanism of u.S. Pat. no. 4,025,204 still rEquires thE MAnufactuRe aNd aSseMblY OF a Number of discrETE comPoNents--soMe oF which iNvoLve RelAtiVeLy close diMensions AnD tOlErAncEs.
AltHOugh not sPeCifIcAllY direCTed to oScillAble TyPe MEchAnisms, vARiOUS attEmPtS havE beEn Made iN the PAst To utiliZe the resiLieNCy or FlExIbility Of certain syntHeTic resins bY cOmbIning vARIous of thE components used in retracTAble typE wrIting And mArking insTruMents. FOr iNStance, u.S. Pat. NOs. 2,898,887, 3,200,792, 3,298,357 and 3,458,264 PrOpoSE PlastIC CoMpoNeNts having iNTEgrAl hinGeS or sPring seCtions. In each instanCE, hoWever, the suggeSteD desIGN iNvoLVeS OnlY a SImpLE Hinge-like or compRessive movEmENt As those in tHE arT wOuld conSider to Be appLIcable pRimarily tO push buttOn Or puSH CliP type mechaNisms invOlving simPLe traNSmIssioN of Linear FoRceS.
U.S. PaT. No. 3,850,531 illUStrAtes a Pencil WiTh an auTomatIc Lead feed Mechanism in which the head Of a driVe scrEw iS disposed BetWEen And revolvEd in Step-like inCreMenTs by a PaiR Of oppOsed SEtS of ANgulaRly
, sleeve, ring or similarmanually a ccess ibl e a ct uati ng p ortion which i s  rot ated back and forth (a xiall yo scil l at ed) b y the u s er t o s hi ft  (r ec i pr ocate ) a  writin g, marking  or  s imilar unitl on gitudinall y b etween a ret rac ted (c on cea l ed) p osi tionwithin the ho using and  a n  exten d ed (poi n t  e xpos ed) position proj e ct i ng through the  lower  ( w ri t i ng)  en d of the h ou sing. Several of t h ese prior proposa ls have met wit h some  d egr e e of c ommer ci a l a cceptance.Even  the more  succe s sful st r uctures , howe ver , h aveb ee nrel at i vel y  c omp l exand henc edi fficu lt a n d e xpen siv e to  prod uce and somew hat  inc o nve nient  to u se a nd  main tain.For i ns tance, U.S. Pat . No s.:
_____ ___ __ ___ __ _____ _ ______ ___ ___ _____ 3 0278733 436 16 0 3 17 6661 3597100 32721 84 3 63 0629 328 9636 3 7 92 93 1  3289637  3 917 4183 4 14359  ___ _ __ ________ ______ _ __ __ _______ __ ____
a re  re pre senta t iveof var ious pri or ar t  proposals for implements wi t ho s ci l labl e t ype mechani smsw hich  not on lya re co mplic at e da nd expensive in ter ms  of th e num ber and compl exity of p a r t s and th eirm an u facture and as sembl y, but ins ome inst ances  require  specialu n its, spe cia l u nit  ad a p te rs, or specia l hand li ng proc edu res.
Th e d esi gndis cl osed in U .S. Pat.  N o.  4 ,0 25, 204 e l iminates  t hene edfor s p ecialunits  orun it ada pters o r  h a n dlin gpr oced ure s,  andothe r wis e provi des vario uss truc tu ra l and f unctional imp ro vements ov er  th e afor e m entioned  prior art. Thus, while compris ing  a si gnif icant adv anc e over  su c h prio r art,  theme cha n i sm of U .S . P at . No. 4,02 5 , 204  stil lrequ ires th e manufacture anda sse mbly of a num ber  ofd i sc ret e  c o mpo ne n ts- - s ome of which in volve rela ti v el y close di m ens io ns andtoleran ces.A lthough  not spec ificallydi rect e d  to  oscillabl e type m echanisms ,  vari o us  atte mpt s have  b een  made  in th e  pa st to  utili ze  the r esili en cy or fl exibility of certain sy ntheti c res ins  by combi nin g  va rious ofthecomponents  us edin re tra c table  typ e  w rit i ng an d ma r king inst r um ent s .  F or instance , U .S.  Pat.  No s . 2,89 8,88 7, 3,200,792, 3,2 9 8,357 and 3,45 8,26 4 pro pos e  pla st ic componentshav in g integral  h inges or sp ring sec ti o ns. I n each  insta nce, ho w e ve r , thesugg est ed design  in vo l ves onl yas implehing e- like o r comp r essi v e  movement as tho se in t he ar t  wo uld c on sider t o  beapplicable  primarilyto pus h bu ttonor push  c lip ty peme chanisms i n volving s imple  transm is sion  of  linea r fo r c es.
U .S.Pa t.No. 3,850 , 5 31 il lu s tra tesa pen ci l wi th an aut o matic le adf eed mec ha nis m in whi c ht h e head ofa d rives c rew is dis p osed be t weenand re volved  in ste p -li ke  increm ent s by a pair  of oppos e d s et s of  angular ly 
, sleeve,_ring or_similar manually accessible actuating_portion which_is_rotated back_and_forth (axially oscillated)_by the user_to shift (reciprocate) a_writing, marking or_similar_unit longitudinally between a retracted (concealed) position within the housing and an extended (point_exposed)_position projecting_through_the_lower (writing) end of the_housing.
Several of these prior proposals_have met_with some degree of commercial acceptance. Even the_more_successful structures, however,_have been relatively complex and hence difficult and expensive_to produce and somewhat inconvenient to_use and maintain._For_instance,_U.S. Pat. Nos.:
______________________________________ 3027873_3436160 3176661 3597100 3272184 3630629 3289636_3792931 3289637 3917418 3414359 ______________________________________
are representative_of various prior art proposals for implements_with oscillable type mechanisms which not_only are complicated and expensive_in terms_of the number and complexity_of parts and_their manufacture_and assembly, but_in some instances require special units,_special unit adapters,_or special handling procedures.
The design disclosed_in_U.S. Pat. No._4,025,204_eliminates_the need_for special units_or_unit adapters_or_handling procedures, and otherwise provides various_structural_and functional improvements over the aforementioned prior_art. Thus, while comprising_a_significant advance over such_prior art, the mechanism of_U.S. Pat. No. 4,025,204 still requires_the manufacture_and assembly_of a number of discrete components--some of which involve relatively close_dimensions and tolerances.
Although not specifically directed_to oscillable type mechanisms,_various attempts_have_been made in_the_past to_utilize the resiliency or flexibility of certain_synthetic resins_by combining various of the components_used in retractable type_writing_and marking instruments. For instance, U.S._Pat. Nos. 2,898,887, 3,200,792, 3,298,357 and_3,458,264 propose plastic components having_integral_hinges_or spring sections. In each_instance, however, the suggested design involves_only a simple_hinge-like or compressive movement as those in_the_art would consider to be applicable_primarily_to push button or push clip_type_mechanisms_involving simple transmission of linear_forces.
U.S. Pat. No. 3,850,531 illustrates a_pencil with an automatic lead feed mechanism in which_the head of_a drive screw is disposed_between_and_revolved in step-like increments by a pair of opposed sets_of angularly