US3899256A - Mechanical pencil - Google Patents

Mechanical pencil Download PDF

Info

Publication number
US3899256A
US3899256A US459854A US45985474A US3899256A US 3899256 A US3899256 A US 3899256A US 459854 A US459854 A US 459854A US 45985474 A US45985474 A US 45985474A US 3899256 A US3899256 A US 3899256A
Authority
US
United States
Prior art keywords
lead
ring
tube
pencil
outside
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US459854A
Other languages
English (en)
Inventor
Yoshihide Mitsuya
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US459854A priority Critical patent/US3899256A/en
Priority to GB1601374A priority patent/GB1456115A/en
Priority to AU67706/74A priority patent/AU485791B2/en
Priority to FR7414002A priority patent/FR2268650A1/fr
Priority to DE2420448A priority patent/DE2420448C3/de
Application granted granted Critical
Publication of US3899256A publication Critical patent/US3899256A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
    • B43K—IMPLEMENTS FOR WRITING OR DRAWING
    • B43K24/00—Mechanisms for selecting, projecting, retracting or locking writing units
    • B43K24/10—Mechanisms for selecting, projecting, retracting or locking writing units for selecting, projecting and locking several writing units
    • B43K24/18—Mechanisms for selecting, projecting, retracting or locking writing units for selecting, projecting and locking several writing units and for feeding the writing-cores
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
    • B43K—IMPLEMENTS FOR WRITING OR DRAWING
    • B43K21/00—Propelling pencils
    • B43K21/02—Writing-core feeding mechanisms
    • B43K21/027—Writing-core feeding mechanisms with sliding tubelike writing-core guide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
    • B43K—IMPLEMENTS FOR WRITING OR DRAWING
    • B43K21/00—Propelling pencils
    • B43K21/02—Writing-core feeding mechanisms
    • B43K21/16—Writing-core feeding mechanisms with stepwise feed of writing-cores
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
    • B43K—IMPLEMENTS FOR WRITING OR DRAWING
    • B43K21/00—Propelling pencils
    • B43K21/02—Writing-core feeding mechanisms
    • B43K21/22—Writing-cores gripping means, e.g. chucks

Definitions

  • Lead extends through the leadprotecting tube and further through a chuck provided above the movable cylinder.
  • a ring is provided for applying a load to the movable cylinder to add to its plunging movement for withdrawing into the pencil proper, the pencil proper having the forward tip directed upward at this time.
  • the ring is the outside of the lead-protecting tube leaving a clearance between the ring and the lead-protecting tube.
  • the outside tube is expanded at the bottom thereof so as to retain the ring therewith at the time of withdrawing the lead into the pencil proper.
  • the present invention relates to a mechanical pencil provided with an improvement in the reciprocating movement of lead in and out of the mechanical pencil proper.
  • a mechanical pencil having such a mechanism as above mentioned usually retracts the lead by pushing a push button attached to the pencil to loosen a lead-trapping chuck, thereby allowing the lead to be pushed into the pencil directly by a finger and the like. Such action very often causes the lead to break.
  • the mechanical pencil 12 has a forward tip portion 11, said forward tip portion 11 has therein a movable cylinder S.
  • Said movable cylinder S in the first embodiment shown in FIG. 1 and 2, comprises a lead-protector 13 made of stainless steel and the like, over which is firmly fitted an outside tube 26 made of elastic material such as rubber and the like, said outside tube 26 having an enlarged outside diameter portion 15 at the bottom thereof and having at the upper inside terminal thereof a projection 27 covering said leadportector 13 all around the periphery thereof.
  • Said projection 27 is smaller in inside diameter than the diameter of lead 28 held in the lead-protector 13 so as to give a suitable friction between the lead and the inside of the elastic projection 27.
  • a ring 17 is adapted to fit outside said lead-protector 13, thereby providing a clearance between said ring 17 and said lead-protector l3.
  • Said ring 17 is situated between the bottom of the outside tube 26 and the bottom 16 of the. inside surface 18 of the forward tip 11.
  • the clearance (a) between the inside surface of the ring 17 and the outside surface of the protector 13 is larger than the clearance (b) between the outside surface of the ring 17 and the inside surface 18 of the forward tip portion 11.
  • the forward tip portion 1 1 at the inside periphery 23 thereof below said female screw is smaller in diameter than the outer diameter of said outer tube 21 and larger than the outer diameter of said chuck 20 in the opened state.
  • a ring 25 which is smaller in inside diameter than the diameter of said movable cylinder S at the expanded part 15 thereof and bigger than the outer diameter of said outside tube 26. Also, in between the lead-container (not shown), positioned at the upper terminal of said guide tube 19 and a retaining portion 29 at the lower terminal of said pencil 12, there is a spring 30 which sustains said guide tube 19 together with said leadcontainer (not shown) upward.
  • the chuck 20 in the opened state rises until it reaches the outer tube 21 and then closes, thereby holding the lead 28 therein again.
  • the lead 28 advances forward at a predetermined pace per each operation of the push button as described above, thus reaching a desired position for writing by way of repeating said operation. Needless to mention, it is desirable to start writing with the lead 28 projecting slightly out of the lead-protector 13 when said lead-protector 13 reaches the lowest position in the pencil 12.
  • the pencil When returning this mechanical pencil to the unused state, i.e., withdrawing the lead into the pencil, the pencil is held vertically so that the forward tip directs upward, as shown in FIG. 2.
  • the chuck 20 is then opened by pushing said push button, resulting in the release of the lead 28 from said chuck 20.
  • the lead 28 and the movable cylinder S fall together under the effect of the friction between the projection 27 and the lead 28.
  • said ring 17 works to give a load to the movable cylinder S, thereby helping the movable cylinder S to fall into the pencil 12 by gravity.
  • Said ring 17, as described above, makes easier the withdrawal of said movable cylinder S into the pencil 12 at a reduced weight of said movable cylinder compared to convention pencil of this kind, thereby reducing the possiblity of breaking the lead under the impact of said movable cylinder when the pencil 12 is dropped or knocked against the ground and the like.
  • a mechanical lead pencil having a forward tip with a cavity therein for containing a movable cylinder portion comprised of a lead-protecting tube extending through and beyond said tip and an outside tube covering within said cavity for surrounding a portion of the end of said lead-protecting tube within said cavity, and a push button controlled chuck located above said movable cylinder when said forward tip is pointed downward for holding and controlling the movement of lead in said pencil through said lead-protecting tube in response to depressing the push button, the improvement comprising:
  • a ring located around said lead-protecting tube immediately below said outside tube covering within said cavity when the forward tip is pointed downward, said ring having an inside radius sufficiently large that the difference between the inside radius of said ring and the radius of said lead-protecting tube is greater than the difference between the outside radius of the ring and the radius of the cavity in which said ring is located, thereby preventing said ring from contacting said lead-protecting tube at any point;

Landscapes

  • Mechanical Pencils And Projecting And Retracting Systems Therefor, And Multi-System Writing Instruments (AREA)
US459854A 1974-04-10 1974-04-10 Mechanical pencil Expired - Lifetime US3899256A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US459854A US3899256A (en) 1974-04-10 1974-04-10 Mechanical pencil
GB1601374A GB1456115A (en) 1974-04-10 1974-04-10 Mechanical pencil
AU67706/74A AU485791B2 (en) 1974-04-10 1974-04-10 Mechanical pencil
FR7414002A FR2268650A1 (en) 1974-04-10 1974-04-23 Mechanical pencil with chuck above movable cylinder - has ring to aid retraction when tip is upward
DE2420448A DE2420448C3 (de) 1974-04-10 1974-04-26 Füllbleistift

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US459854A US3899256A (en) 1974-04-10 1974-04-10 Mechanical pencil
GB1601374A GB1456115A (en) 1974-04-10 1974-04-10 Mechanical pencil
AU67706/74A AU485791B2 (en) 1974-04-10 1974-04-10 Mechanical pencil
FR7414002A FR2268650A1 (en) 1974-04-10 1974-04-23 Mechanical pencil with chuck above movable cylinder - has ring to aid retraction when tip is upward
DE2420448A DE2420448C3 (de) 1974-04-10 1974-04-26 Füllbleistift

Publications (1)

Publication Number Publication Date
US3899256A true US3899256A (en) 1975-08-12

Family

ID=60200854

Family Applications (1)

Application Number Title Priority Date Filing Date
US459854A Expired - Lifetime US3899256A (en) 1974-04-10 1974-04-10 Mechanical pencil

Country Status (5)

Country Link
US (1) US3899256A (enrdf_load_stackoverflow)
AU (1) AU485791B2 (enrdf_load_stackoverflow)
DE (1) DE2420448C3 (enrdf_load_stackoverflow)
FR (1) FR2268650A1 (enrdf_load_stackoverflow)
GB (1) GB1456115A (enrdf_load_stackoverflow)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4149813A (en) * 1976-03-19 1979-04-17 A. W. Faber-Castell Mechanical pencil with automatic and manual lead advance
US4171170A (en) * 1977-03-31 1979-10-16 Kotobuki & Co., Ltd. Automatic pencil
US4411543A (en) * 1979-10-29 1983-10-25 Pentel Kabushiki Kaisha Self-feeding mechanical pencil
US5117583A (en) * 1990-07-25 1992-06-02 Reum Mark T Landscape terracing material
JP2016168824A (ja) * 2014-05-30 2016-09-23 ぺんてる株式会社 シャープペンシル

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2609671C2 (de) * 1976-03-09 1983-11-24 Helmut Dipl.-Ing. 8501 Altenberg Bross Mechanischer Druckbleistift mit beweglichem Minenschutzrohr
US4270870A (en) * 1977-05-22 1981-06-02 Ancos Co., Ltd. Mechanical pencil with chuck closing by normal writing grip

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2385329A (en) * 1944-06-02 1945-09-25 J D Buchanan Pencil
US2532748A (en) * 1948-09-14 1950-12-05 Koh I Noor L & C Hardtmuth Push-cap operated pencil
US3537799A (en) * 1967-12-20 1970-11-03 Fumiko Sakamoto Mechanical pencil
US3804536A (en) * 1971-03-24 1974-04-16 Ancos Co Ltd Slide type mechanical pencil

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2385329A (en) * 1944-06-02 1945-09-25 J D Buchanan Pencil
US2532748A (en) * 1948-09-14 1950-12-05 Koh I Noor L & C Hardtmuth Push-cap operated pencil
US3537799A (en) * 1967-12-20 1970-11-03 Fumiko Sakamoto Mechanical pencil
US3804536A (en) * 1971-03-24 1974-04-16 Ancos Co Ltd Slide type mechanical pencil

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4149813A (en) * 1976-03-19 1979-04-17 A. W. Faber-Castell Mechanical pencil with automatic and manual lead advance
US4171170A (en) * 1977-03-31 1979-10-16 Kotobuki & Co., Ltd. Automatic pencil
US4411543A (en) * 1979-10-29 1983-10-25 Pentel Kabushiki Kaisha Self-feeding mechanical pencil
US5117583A (en) * 1990-07-25 1992-06-02 Reum Mark T Landscape terracing material
JP2016168824A (ja) * 2014-05-30 2016-09-23 ぺんてる株式会社 シャープペンシル

Also Published As

Publication number Publication date
DE2420448A1 (de) 1975-11-06
DE2420448C3 (de) 1981-08-06
FR2268650B1 (enrdf_load_stackoverflow) 1976-12-17
DE2420448B2 (de) 1980-11-27
AU6770674A (en) 1975-10-16
FR2268650A1 (en) 1975-11-21
GB1456115A (en) 1976-11-17
AU485791B2 (en) 1975-10-16

Similar Documents

Publication Publication Date Title
US2348337A (en) Hypodermic projectile
US3899256A (en) Mechanical pencil
US3537799A (en) Mechanical pencil
US2913750A (en) Lip cosmetic brushes
US4831998A (en) Pellet dispenser
US3664753A (en) Pushbutton type mechanical pencil
US3187723A (en) Pencil box
US2670121A (en) Flexible follower for metal ampoules
CN108656791B (zh) 一种笔尖自动回缩的中性水笔
US3054312A (en) Rotary-impact type hand tool
US3232278A (en) Writing instrument
US3205862A (en) Mechanical pencils
US3914059A (en) Mechanical pencil
US2864494A (en) Lipstick structures
US2500439A (en) Writing instrument
EP0448377B1 (en) Drawing device for use in drafting machine
US2179835A (en) Step-by-step lead pencil
JP2551810B2 (ja) ノック式筆記具の衝撃減衰機構
US2510312A (en) Mechanical pencil with step-bystep push feed
US3523741A (en) Lead pencil having means adapted to control the drop of the refill lead
US2700959A (en) Mechanical pencil
US2627842A (en) Mechanical pencil of the push-button type
US2532748A (en) Push-cap operated pencil
JPS5837667Y2 (ja) ノツク式シヤ−プペンシル
CN108656792A (zh) 一种防止笔尖损坏的书写笔