Claims:
What is claimed is
1. A writing instrument comprising a barrel including a barrel wall, said barrel having a first opening at one end thereof, a writing unit slidably mounted in said barrel, a push button member slidably mounted in said barrel in non-rotatable fashion, said push button member having teeth extending therefrom, a protract-retract mechanism in said barrel for placing said writing unit in predetermined protracted and retracted positions with respect to said first opening, said protract-retract mechanism including biasing means in said barrel constantly urging said writing unit to retract, a rotatable lug member mounted on said writing unit and having a first lug formed thereon such that said biasing means forces said first lug against the teeth of said push button member when said push button member is depressed, at least one of the engaging surfaces of said push button member teeth and said first lug being inclined such that said rotatable lug member is rotatably biased when said first lug is forcibly engaged with said teeth by said biasing means, said protract-retract mechanism further including a nonmovable cam formed on the interior of said barrel, said cam including at least one cam element bordered by longitudinal deep slots such that the first lug of said rotatable lug member is longitudinally displaceable in at least one of said deep slots when said writing unit is being shifted from one of said predetermined positions to the other said predetermined position, said cam element having an end portion continuously inclined from one of said longitudinal deep slots to the other said longitudinal deep slot such that said biasing means forces said first lug into engagement with said continuously inclined end portion when said writing unit is being shifted from one of said predetermined positions to the other said predetermined position, said writing instrument further including a second opening in the barrel wall and a deflectable resilient member provided on said barrel, said deflectable resilient member having a projecting portion projecting through said second opening to block movement of said rotatable lug member when said first lug is on the inclined end portion of said cam element and when said writing unit is in said protracted position, said blockage of said rotatable lug member by said projecting portion maintaining said first lug on the inclined end portion of said cam element, said projecting portion being deflectable away from said rotatable lug member to unblock said rotatable lug member such that said biasing means causes further movement of said first lug on the continuously inclined end portion of said cam element whereby said first lug moves off said inclined end portion into one of said longitudinal deep slots to enable said writing unit to shift from said protracted position to said retracted position without actuation of said push button member.
2. A writing instrument as claimed in claim 1 wherein said rotatable lug member includes a second lug spaced from said first lug, said projecting portion being engageable with said second lug to block movement of said rotatable lug member when said first lug is engaged with the inclined end portion of said cam element and said writing unit is in said protracted position.
3. The writing instrument of claim 1 wherein said second barrel opening and said projecting portion are at a predetermined level on said barrel such that said projecting portion blocks rotatable movement of said rotatable member in said one direction when the lug member of said rotatable member is at said predetermined level with said projecting portion, said push button member being reciprocable beyond said predetermined level to move the lug member of said rotatable member past said pre-determined level out of engagement with said projecting portion, the force of engagement between the engaging surfaces of said push member teeth and said rotatable member caused by said biasing means rotatably biasing said rotatable member whereby the lug member of said rotatable member moves in said one rotational direction away from said projecting portion.
4. The writing instrument of claim 1 further including an elongated pocket clip member provided on said barrel, said deflectable member extending from said projecting portion outwardly of said barrel toward said pocket clip member.
5. The writing instrument of claim 4 wherein said deflectable member is a resilient leaf spring.
6. The writing instrument of claim 4 wherein said deflectable member is formed as an extension of said pocket clip member.
7. The writing instrument of claim 4 wherein said deflectable member is joined to said pocket clip member.
8. The writing instrument of claim 4 wherein said deflectable member joins said pocket clip at a level spaced from the level of said barrel wall opening such that said deflectable member is inclined toward said barrel from its junction with said pocket clip.
9. The writing instrument of claim 4 wherein said deflectable member is a resilient leaf spring pivoted at said pocket clip, the projecting portion being movable outwardly of said second barrel opening upon deflection of said leaf spring in said predetermined direction about said pivot toward said pocket clip.
Description:
This invention is directed to new and useful improvements in pens with retractable writing tips and more particularly to a pen having provision for automatic retraction of the writing tip as the pen is clipped to a pocket.
Retractable pens generally include pocket clips for securing the pen in a pocket when the writing point is retracted and the pen is not being used. Occasionally a pen is clipped into a pocket while the writing tip is protracted. The writing point thus contacts and stains the pocket material.
Among the several objects of the present invention may be noted the provision of a novel retractable pen; a novel retractable pen having provision for automatic retraction of the writing tip as the pen is clipped to a pocket; and a novel retractable pen having a writing tip that can be manually retracted by depressing a push button or automatically retracted as the pen is being clipped into a pocket. Other objects and features will be in part apparent and in part pointed out hereinafter.
The present invention relates to a novel retractable pen having a writing tip that can be protracted and retracted manually and if necessary automatically retracted as the pen is clipped into a pocket.
In one embodiment of the invention the pen comprises a barrel with a push button member having teeth extending therefrom for engagement with means for locating a writing unit in predetermined protracted and retracted positions with respect to the barrel. The locating means include a rotatable lug member mounted over an end of the writing unit for rotating reciprocable movement in and out of cam slots formed on the barrel interior. A resilient spring member is pivoted to a pocket clip that is secured to the pen barrel, the spring member having a projecting portion thereon projecting into the barrel interior for engagement with the rotatable lug member when the writing unit is in its protracted position. A depression of the push button member or a deflection of the resilient spring member as when the pen is clipped into a pocket, disengages the projecting portion from the lug member to enable biasing means in the pen barrel to urge the pen unit into a retracted position.
The invention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the following claims.
In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,
FIG. 1 is an elevational view partly shown in section of a pen incorporating one embodiment of the present invention wherein the writing unit is in a retracted position;
FIG. 2 is an enlarged sectional view taken on the line 2--2 of FIG. 1;
FIG. 3 is an enlarged sectional view taken on the line 3--3 of FIG. 1;
FIG. 4 is a view similar to FIG. 1 wherein the writing unit is in a protracted position;
FIG. 5 is an enlarged sectional view taken on the line 5--5 of FIG. 4;
FIG. 6 is a development of the pen clip shown in FIGS. 1 and 4; and
FIG. 7 is a perspective view of the push button member shown in FIGS. 1 and 4.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.
Referring now to the drawings for a detailed description of the present invention, a pen incorporating one embodiment thereof is generally indicated at 20. Pen 20 comprises a known writing unit cartridge 22 disposed in a barrel member 24 made of any suitable material such as plastic. A push button member 26 disposed at one end of barrel 24 comprises a hollow cylindrical base portion 27 having eight teeth 28 extending from one end thereof and a stem 29 extending from the opposite end thereof. Eight stub projections 31 are formed on the periphery of base portion 27 spaced from, yet longitudinally aligned with respective teeth 28.
A clip member 30 is secured to the exterior of barrel 24 near push button member 26 in any suitable known manner. Cartridge 22 can be protracted and retracted through an opening 32 at an opposite end of barrel 24 and is constantly urged toward a retracted position by a known biasing spring 34 in barrel 24.
Means for locating writing unit 22 in predetermined protracted and retracted positions include a lug member 36 disposed at one end of cartridge 22, and a cam means 38 formed on the interior of barrel 24. Lug member 36 which has four peripheral lugs 40 is of known structure and telescopically engages base portion 27 of push member 26. Cam means 38 has a peripheral terminal portion 42 and a first cam element 44 comprising a ridge portion 46 extending downwardly as viewed in FIG. 1 from terminal portion 42. Ridge portion 46 is bordered on opposite sides by spaced and parallel deep slots 48, 50 extending downwardly from terminal portion 42. A relatively shallow slot 52 extending downwardly from terminal portion 42 is formed in ridge 46 intermediate deep slots 48 and 50.
As seen most clearly in FIG. 1, an end portion 54 of ridge 46 is continuously tapered such that a crest portion 56 of tapered end 54 is adjacent deep slot 48 and a root portion 58 of tapered end 54 is adjacent deep slot 50. A second cam element 60 structurally similar to cam element 44 is formed on the interior of barrel 24 opposite cam element 44. Cam element 60 includes deep slots 62, 64 defining a ridge portion 66 having a shallow slot 68 formed therein which ridge includes a tapered end similar to tapered end 54 having a crest portion 70 adjacent deep slot 64 and a root portion 72 adjacent deep slot 62.
Oppositely disposed parallel flat face portions 74 and 76 are formed on the interior of barrel 24 intermediate cam elements 44 and 60. The distance between flat face portions 74 and 76 is approximately equal to the distance between shallow slots 52 and 68. Flat face portion 76 which is typical, extends downwardly from terminal portion 42 as viewed in FIG. 1 to a level that is approximately equal to the distance of root portions 58 and 72 from terminal portion 42.
Clip member 30 can be formed from any suitable material such as sheet metal and comprises a body portion 77 having flanges 78, 80 and 82 tacked to barrel 24 in any suitable manner. A resilient deflectable spring member 84 formed as an extension of body portion 77 has a first bent portion 86 contacting barrel 24. Deflectable spring member 84 also includes a second bent portion 88 projecting into barrel 24 through an opening 90. Spring member 84 is biased so that bent portion 88 normally projects beyond the inner wall surface of barrel 24 a predetermined amount.
As seen in FIG. 1 lugs 40 of lug member 36 are urged against push button member teeth 28 in a known manner by spring 34 when writing unit 22 is in a retracted position. As best seen in FIG. 2, a pair of oppositely disposed stub projections 31, 31 are slidably confined in shallow slots 52, 68 to prevent rotation of push button member 26. Also, all four lugs 40 of lug member 36 are slidably confined in deep slots 48, 50, 62 and 64.
In using pen 20 writing unit 22 is moved from its retracted position to a protracted position, as shown in FIG. 4, by depressing push button member 26 thereby forcing lug member 36 downwardly toward the tapered end portion of ridges 46 and 66. Lug member 36 is rotatably biased in a counterclockwise direction, as viewed in FIG. 2, in a known manner by the force of push member teeth 28 against lugs 40 in opposition to the biasing force of spring 34.
It should be noted that the stroke of push button member 26 is less than the length of shallow slots 52 and 68 such that stub projections 31, 31 in slots 52 and 68 are continuously confined therein whenever push button member 26 is depressed. However depression of push button member 26 pushes lugs 40 of lug member 36 out of deep slots 48 and 64 beyond crest portions 56 and 70. Consequently as push button member 26 forces lugs 40 beyond crest portions 56 and 70 lug member 36 being rotatably biased will rotate, and biasing spring 34 will urge a pair of lugs 40 against crest portions 56 and 70. Lug member 36 will then rotate counterclockwise as viewed in FIG. 2 in a known manner due to the biasing force of spring 34 and the complementary slopes of lugs 40 and crest portions 56 and 70 such that lugs 40, 40 move toward root portions 58 and 72.
As seen in FIGS. 2 and 5 a barrel opening 90 is oriented approximately 90° from either root portion 58 or 72. Barrel opening 90 is located at a predetermined level on barrel 24 such that bent projecting portion 88 is engageable with one lug 40 (FIG. 5) when lug member 36 has rotated lugs 40, 40 on crest portions 56 and 70 counterclockwise as described toward root portions 58 and 72. In this manner the engagement of bent projecting portion 88 with said one lug 40 blocks further rotatable movement of lug member 36 thereby maintaining writing unit 22 in the protracted position of FIG. 4.
Although bent projecting portion 88 has been shown oriented approximately 90 degrees from root portions 58 and 72 other orientations are feasible. For example, barrel opening 90, bent projecting portion 88 and clip 30 can be repositioned from the orientation of FIGS. 2, 3 and 5 to an orientation (not shown) in alignment with either root portion 58 or 72 at the same predetermined level on barrel 24 previously mentioned. Also, if desired bent projecting portion 88, barrel opening 90 and clip 30 can be oriented directly opposite their present location.
Writing unit 22 is moved from its protracted position to the retracted position of FIG. 1 by depressing push button member 26 downwardly against lug member 36. The opposing forces of push button member 26 and spring 34 against lug member 36 rotatably bias lug member 36 in a known manner such that when the lug 40 engaged with bent projecting portion 88 is moved past bent projecting portion 88 by push button member 26 lug member 36 is free to rotate a predetermined amount to align all of the lugs 40 with deep slots 48, 50, 62 and 64. When push button member 26 is released lugs 40 are urged into the deep slots by the biasing force of spring 34.
Writing unit 22 can also be moved from its protracted position to the retracted position of FIG. 1 by deflecting spring member 84 toward body 77 of clip 30. Deflection of spring member 84 causes bent projecting portion 88 to move outwardly of opening 90 thereby disengaging bent projecting portion 88 from lug 40. The pair of lugs 40, 40 at root portions 58 and 72 rotate thereon due to the biasing force of spring 34 and the complementary engaged slopes of lugs 40 and root portions 58 and 72. Lug member 36 thus rotates to a position wherein all lugs 40 are aligned with deep slots 48, 50, 62 and 64 to slide therein as previously described.
Spring member 84 can be deflected in the desired manner by clipping pen 20 to a pocket. As pocket material is inserted between clip 30 and barrel 24 it forces bent portion 86 away from barrel 24 causing spring 84 to deflect a predetermined amount sufficient to disengage bent projecting portion 88 from lug 40 and thereby enable writing unit 22 to retract from its protracted position. If desired, a portion of barrel 24 can be formed with a depression in which bent portion 86 is seated prior to deflection of spring 84.
When pen 20 is clipped to a pocket bent projecting portion 88 remains deflected outwardly of opening 90. Consequently if push button member 26 is accidentally depressed and writing unit 22 is inadvertently moved from a retracted to a protracted position while pen 20 is clipped to a pocket, writing unit 22 will not remain protracted because bent projecting portion 88 remains deflected outwardly of opening 90.
As will be apparent to those skilled in the art cam elements similar to elements 44 and 60 can be substituted for flat face portions 74 and 76 of barrel 24. Further, as will be apparent to those skilled in the art, cam means 38 can be of the rotatable type known in the art coacting with fixed lug elements formed on a pen barrel as is also known in the art, with bent projecting portion 88 arranged to engage and disengage from the rotatable cam means in a manner similar to that previously described for engagement and disengagement from lug member 36. Bent projecting portion 88 can be replaced by any suitable known stud or the like having one end bonded to spring member 84 such that the opposite end projects into barrel opening 90. Other arrangements known in the art can be used to bias spring member 84 toward barrel 24 to normally maintain bent projecting portion 88 in barrel opening 90.
Clip 30 need not be formed in one piece. Conventional pen clips can be used with spring member 84 formed as a separate member (not shown) pivotally secured to the conventional clip in any suitable known manner to operate in the manner previously described. Stub projections 31 on base portion 27 slidably confine push button member 26 in barrel 24 in non-rotatable fashion. Although eight stub projections 31 are disclosed, two oppositely disposed stubs in shallow slots 52 and 68 would be sufficient. It is also not necessary that stubs 31 be aligned with teeth 28.
An advantage of the novel retractable pen evident from the foregoing description includes the provision of a pen that can be protracted and retracted by a push button member and also retracted without depressing the push button member. Another advantage is a pen having a writing unit that can be retracted as the pen is clipped into a pocket. The resilient deflectable spring member on the pocket clip functions as an automatic reminder device for retracting the protracted writing unit if the pen is inadvertently inserted in a pocket while the writing unit is in a protracted position. Still another advantage is a pen having a writing unit that always seeks a retracted position while the pen is clipped in a pocket.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.