Abstract: A rotary knock type mechanical pencil in which the forward and rearward outer cylinders are relatively rotated, a cam movement converting mechanism stored in the forward outer cylinder converts the rotary movement into an axial advancing or retracting movement, the lead feeding mechanism may feed the lead of desired length from the extremity end of the mechanical pencil under a knocking operation in the shaft comprising: a cam cylinder integrally rotating with the rearward outer cylinder that includes two cam surfaces and an engaging part which allows retraction of a lead guide pipe; a rotary cam mechanism for converting the rotary movement of the cam cylinder into a reciprocating advancing or retracting movement while slidably contacting with the cam surface formed at the extremity end surface of the cam cylinder; a lead feeding mechanism including an advancing or retracting mechanism such as a cassette adapter for advancing or retracting the lead chuck attached to the extremity end under a reciprocating mov

Abstract: A mechanical pencil comprising a tubular casing, a centrally apertured conical tip piece connected to an end of the tubular casing to form a pencil tip, a lead engaging chuck device longitudinally movably mounted within the tubular casing, first spring for biasing the chuck device rearwardly relative to the chuck actuator, second spring for biasing the chuck actuator longitudinally forwardly and circumferentially relative to the tubular casing, actuation knob device longitudinally mounted on the tubular casing for rotation the chuck actuator against a resilient force of the second spring, engagement device for slidably engaging the chuck actuator against a resilient force of the second spring, and locking device for locking the chuck actuator to prevent a further rotation of the chuck actuator to thereby release the engagement between the actuation knob and the chuck actuator.

Abstract: A mechanical pencil is disclosed in which lead feed occurs automatically upon lifting of the pencil from the paper surface or the like and in which the slider can be locked in a retreated position when the pencil is not in us.

Abstract: A lead chuck of a mechanical pencil to be assembled into a lead feeding mechanism of a rear end knock type, an automatic lead feeding type and an extremity end knock type mechanical pencil in which it is arranged within the sleeve through a resilient member in such a way as it may be advanced or retracted. A lead holding part is formed at the extremity end portions of the divided surfaces of the chuck members which are fully divided into two sections along an axial plane. The lead holding part is formed with several teeth for use in holding the lead under four-point or six-point contacted condition within axially formed grooves made at the central portions of the divided surfaces. The teeth are projected in several rows and formed at the raised surfaces of the grooves.

Abstract: This invention relates to a container for feeding a bar shaped article such as an erasing gum, a pencil lead, a crayon, a pastel, or an eyebrow stick, especially for advancing or retracting the bar shaped article. A bar shaped article (8) is inserted into an inner sleeve (2) from the rear end with the outer sleeve (1) being held by the hand, then the rear end of the inner sleeve (2) is pressed. Inner sleeve (2) moves forward and rearward against the resilient force of an elastic biasing member (3). A chuck (4) at the end of the inner sleeve (2) opens and closes repeatedly and the end of the bar shaped article (8) is fed out and can be used. When the chuck (4) holds the bar shaped article (8) in an unused state a chuck open means opens the chuck 4 slightly and loosens the securing force preventing encroachment of the chuck (4) into the article (8) allowing the chuck (4) to easily separate from the article (8) when the article (8) is fed out.

Abstract: A push-type writing instrument essentially comprising an outer body having a tapered forward portion in which lead is retained. The lead is retained by a pair of radially opposed fingers provided on the tapered forward portion for frictional engagement with a lead. A lead containing inner sleeve has a rearward section of a larger diameter and a forward section of a substantially smaller diameter. The forward section of the inner sleeve is formed with a tapered portion having a pair of longitudinal slots rendering the tapered portion a radially contractible nature thereby constituting a lead clamping means in a cooperative manner with a slidable tightening ring provided about the tapered portion. A spring is coiled about the forward section of the inner sleeve for urging the inner sleeve to retain the writing instrument in a normal writing position.

Abstract: A mechanical pencil has a body with a lead storage chamber defined therein for housing spare lengths of lead, and a tubular lead guide receiving a length of lead and coaxially mounted in the body so as to partly protrude outwardly from its writing end. During writing or marking, the lead guide gradually retracts into the body against the force of a return spring with the wear of the lead received therein and, when the pencil is moved off the writing surface, it is held in place by a locking mechanism until a preselected wear point is reached, then it is sprung back to its normal position. Disposed intermediate the lead storage chamber and the lead guide, a chuck coacts with an internally tapered socket for gripping the lead against displacement away from the writing end of the body.

Abstract: An automatic lead advance for a mechanical pencil having a tubular casing, a conical member joined to the front end portion of the tubular casing, a ring fixed to the inner surface of the conical member, an annular pivotable member provided at the front side of the ring, a lead guide tube having a lead retainer, urged backward by a spring, adapted to the slidable in the axial direction, and positioned so that the portion of the front end surface of the pivotable member which is away from the fulcrum of pivotal movement thereof contacts the rear end portion of the lead guide tube, a ball chuck mechanism urged forward by a knock spring and adapted to be movable between the rear end surface of the ring and an end surface of a stepped portion formed on the inner surface of the tubular casing, and a stopper provided at the front end of an outer tube of the ball chuck mechanism and contacting at the front end surface thereof the portion of the rear end surface of the pivotable member which is close to the fulcrum o

Abstract: A lead cartridge opening and closing unit wherein outward engaging piece portions are provided on a chuck type opening and closing mechanism which is divided into sections in the diametrical direction and has inward elastic force and which is further disposed on the lead cartridge; the outward engaging piece portions moving inwardly against the inward elastic force along the diametrical direction thereof thereby to open lead conducting holes in case of forcible insertion into and engagement with a lead guide, while the outward engaging piece portions being restored by means of the inward elastic force to move outwardly along the diametrical direction thereof thereby to close the lead conducting holes in case of release for the forcible insertion and engagement; whereby when the outward engaging piece portions of the chuck type opening and closing mechanism are forcibly fitted in the lead guide, the outward engaging piece portions move inwardly along the diametrical direction thereof to be resiliently fitted t

Abstract: The lead reservoir and feed mechanism of a knock type mechanical pencil is secured to the tubular barrel in which it is housed by a resilient locking sleeve positioned in a groove near the front of the feed mechanism and a spring compressed between a rearwardly facing internal abutment on the feed mechanism. The spring urges the lead reservoir and feed mechanism rearwardly into the barrel to a position where an external flange on the locking sleeve abuts the front end of the barrel.

Abstract: Mechanical pencil in which a chuck assembly for gripping a lead is formed with plural chuck elements mutually combined with each other. The chuck assembly has an internal longitudinal hole to insert a lead through and a lead gripping portion to grip the lead, while a lead guide tube is movably inserted within the lead inserting hole. The lead guide tube pushes on acting portions of the chuck to open the gripping portions of the chuck elements in the direction of parting them from each other when the lead guide tube is advanced, and the lead gripping portion opens to release the lead. The chuck is designed to enable releasing and gripping the lead securely so that it can be suitably used as a chuck mechanism for extending the lead automatically.

Abstract: A push-button type mechanical pencil consisting of a barrel which is composed of a clip-carrying upper barrel member and a metal tip-carrying lower barrel member, which barrel members are engaged with each other at a substantially intermediate portion of the barrel and joined to each other by a rotary unit structure so that the barrel members can be turned with respect to each other, a movable cylinder provided in the unit structure and adapted to be moved forward and backward in the axial direction owing to a screw pair, and a lead-extruding structure provided in the barrel and capable of projecting a lead in a stepped member by a very small length at a time by pressing the upper end of a push-down tube, which lead-extruding structure includes a push-button member projecting from the rear end of the barrel, a protective pipe provided in a bore at the free end of a metal tip provided at the lower portion of the lead-extending structure, and an outer tube fixed to the movable cylinder in the unit structure to

Abstract: A mechanical pencil wherein a slider 11 in contact with a lead and an outer tube 1 with different frictional resistances other than a lead delivery mechanism for effecting lead-feed by general knocking operation are provided within the outer tube 1 or a fore means 2, whereby the end of a consumed lead 19 is pressed against or released from a surface of paper or the like to thereby project the lead 19 from a lead guide 12 by an amount corresponding to backward movement of the slider 11. The lead-feeding may be easily accomplished merely by pressing operation without changing the grip of the outer tube 1.

Abstract: A mechanical pencil for automatic drawing machines is disclosed which feeds lead segments to the writing surface as the pencil is alternately pressed against and lifted from the writing surface. The pencil includes a housing having a reserve lead containment chamber and a main internal cavity. A collet split into two portions is mounted within the internal cavity beneath an opening between the main cavity and the containment chamber and has outer cone-shaped camming surfaces and first and second axially spaced, cylindrical inner clamping surfaces. A friction tube with an inner bore adapted to frictionally engage a lead segment is mounted beneath the collet and holds a lead segment to support it against the writing surface.

Abstract: A continuous feed mechanical pencil includes a lead cartridge having a lead advancing mechanism responsive to forward axial movement of an actuator button protruding from the rear end of the instrument, the actuator button being fixedly attached to a pocket clip and extending a relatively short distance from the rear of the instrument housing so that the rear end of the actuator is shrouded by the rear end of the housing when the actuator button is fully depressed.

Abstract: A cosmetic pencil containing a cosmetic mass in a thin pencil lead-like configuration. The pencil has a cosmetic mass or crayon-containing sheath and the cosmetic mass may be metered from the pencil by moving a gripping disk inwardly with respect to the sheath. This is done by turning the sheath, by moving it inwardly with respect to the pencil or by pushing a button at the back of the pencil. The mass is forced out of the sheath in a small, metered amount. The cosmetic mass may be cast in the sheath.

Abstract: A mechanical pencil in which a lead delivery mechanism composed of a lead tank part, a lead chuck, a chuck ring, a sleeve having a stopper and the like is inserted into an outer cylinder having a stopper engaging portion from the rear of the outer cylinder in axially slidable manner, a stopper fitting stepped portion is positioned on the tank part apart from the stopper with a distance equivalent to or shorter than the knocking stroke, and the lead tank part is knocked so that the stopper is fitted to the stopper engaging portion of the outer cylinder, and a method for assembling such mechanical pencil.

Abstract: A lead delivery mechanism is integrally composed of a lead chuck for biting lead fitted to the extreme end of a lead pipe, sleeves abutting upon a chuck clamping ring loosely fitted to the head portion of the lead chuck, a spring member for clamping the chuck disposed resiliently between the sleeves and the lead pipe, and a locking ring locked loosely with the lead chuck to lock the rear end of the spring member, whereby such lead delivery mechanism may be handled as a block in assembly operations for mechanical pencils.

Abstract: A mechanical pencil having an exchangeable lead storing container has a feeding mechanism provided at one end with a coupling pin which snugly fits a coupling recess formed in the storing cartridge. The feeding opening connecting the interior of the cartridge with the central passage in the coupling pin has normally a smaller diameter than that of leads stored in the cartridge, and only upon completing the coupling the pin enlarges the feeding opening to such an extent that the stored leads can freely pass one after the other into the feeding mechanism of the pencil.

Abstract: An improvement in the mechanical pencil of the type shown in U.S. Pat. No. 4,320,982. The improved mechanical pencil has a tubular outer casing, a coil spring disposed within the outer casing and an inner tube slidably inserted through the outer casing and the coil spring, the inner tube being adapted to store therein a plurality of presharpened lead pieces and having a conical shaped head formed at its lower end, the conical head being provided with two slots to form into a pair of clamping halves for clamping and releasing the presharpened lead pieces. The coil spring, which is adapted to urge the inner tube upwards, has a lowermost coil provided with a straight tail extending from the lowermost coil inwardly and downwardly at a predetermined angle with the longitudinal center axis of the coil spring, to fit into one of the two slots of the conical shaped head of the inner tube, with the tip of the tail being arranged to abut the rear end of the lead piece clamped by the clamping halves.

Abstract: A mechanical pencil having a chuck mechanism which permits the lead to advance but prevents the lead from retracting, a first slider, a second slider which is retractable progressively as a writing pressure is applied, a first engagement device for holding the second slider at its retracted position and a second engagement device for holding the first slider at its retracted position. The progressively retracted second slider is released to advance to the forward original position by applying a further writing pressure to cause a retraction of the first slider. Then, the second slider is advanced forwardly together with the lead so that the lead is advanced to a writing position.

Abstract: A lead propelling mechanism for a mechanical pencil includes a lead chuck, a ring fitted loosely about the chuck for tightening its head, a sleeve having a front end contacting the ring, and an elastic member having a front end bearing on the front end of the sleeve and a rear end held by a shoulder formed on the outer surface of the chuck adjacent to its rear end. The mechanism is very easy to assemble and join to a lead holding tube in the pencil. The rear end of the elastic member bears against an adjacent end of the tube to urge the ring to tighten the head of the chuck, when the chuck is inserted into the tube.

Abstract: A mechanical pencil reduced in the number of the component parts and facilitating the assembling work, comprising an outer cylinder, a replaceable lead cartridge, a tip member including a cushion member capable of contracting according to writing pressure that works on the lead so that the lead is retracted into the tip member when an excessive writing pressure works on the lead to prevent the breakage of the lead, and a lead feeding mechanism which is constructed within the tip member prior to the connection of the tip member to the outer cylinder.

Abstract: A mechanical pencil is constructed of (a) a decorative barrel to be held by a user; (b) a lead-feeding mechanism disposed within the decorative barrel; (c) a lead guide connected to the lead-feeding mechanism; and (d) a lead-containing cartridge having an outer diameter substantially equal to the inner diameter of the decorative barrel and held detachably in the decorative barrel. The mechanical pencil according to the present invention can be continuously used by simply replacing a used-up cartridge with a fresh cartridge containing a plurality of writing leads. Thus, it is unnecessary, different from conventional mechanical pencils, to insert a fresh supply of writing leads one by one into the mechanical pencil. Since a user is not required to touch writing leads directly, his hands are not smeared.

Abstract: A propelling pencil comprising an outer cylinder made of synthetic resin which can be easily molded as a unitary structure and an engaging member incorporating a chuck device including a lead propelling mechanism, the engaging member being detachably inserted into the outer cylinder from the rear side thereof, and thereby providing excellent appearance and light-touching operation.

Abstract: A mechanical pencil comprising a lead feed mechanism built within the body thereof and a lead guide connected to the lead feed mechanism and having a cartridge reception bore of a diameter which is practically the same as the inside diameter of the body, wherein a cartridge containing a plurality of leads and having an outside diameter which is practically the same as the inside diameter of the body and the inside diameter of the cartridge reception bore of the lead guide is detachably fitted in the cartridge reception bore of the lead guide. In replenishing the mechanical pencil with leads, an old cartridge is replaced with a new cartridge.

Abstract: A knock-type propelling pencil, of which a lead casing is made in the form of a cartridge so that supply of new spare leads can be completed by only inserting the cartridge accommodating the given leads into lead cylinder in outer cylinder and thereby making the operation of supply of the new spare leads easier.

Abstract: A mechanical pencil having a cylindrical barrel (1) and a sheath (2) in axial relationship is disclosed. A spiral member (4) in fixed relationship with the sheath and in axially sliding relationship with the barrel for a predetermined range engages a slider (7). The slider is in fixed relationship with a push feed type writing unit and slides axially within a predetermined range within the barrel (1) as allowed by a guide (3). First spring means is provided to urge the spiral member in a forward direction when the writing unit is positioned axially such that it is contained within the barrel (1). As the writing unit is moved from its rearmost position within the barrel (1) to a protruding position by rotation of the spiral member (4), a second spring means urges the spiral member in a rearward direction, forming a gap between the barrel (1) and the sheath (2).

Abstract: A chuck mechanism incorporated in a mechanical pencil has a plurality of chuck elements in a longitudinal confronting relation. The chuck elements have a pivotal support or fulcrum at their opposing rearward portions so that the elements are pivotable about the fulcrum. The fulcrum is formed proximal to the rear end and distal to the front end jaw portions of the chuck elements. When an axial force is applied to the chuck elements, the jaw portions of the chuck elements are opened to release lead engagement thereby. The rear portion relative to the fulcrum is a portion where an axially forward thrust added thereto is converted to a radially inward thrust to the rear portion.

Abstract: A mechanical pencil comprising a pencil barrel, a cam cylinder mounted in the pencil barrel at a front portion thereof and having a cam wall formed on an inner circumferential surface, a cylindrical slide cam engaged with the cam wall for back-and-forth movement therein, a rotatable cam disposed in front of the slide cam and having a central hole, an inner fitting and a clamp support connected together and disposed in front of the rotatable cam, a pusher for pushing the slide cam, a spring for urging the inner fitting and the clamp support to move backwardly, the inner fitting, a lead holder mounted in the inner fitting for holding a lead with a light force, a cylindrical clamp disposed behind the lead holder and movable back and forth by a slight interval, a chuck fitted in the clamp, a lead pipe connected to a rear end of the chuck and having a diameter small enough to allow passage therethrough of one lead at a time, the lead pipe extending through the rotatable cam and the slide cam, a lead casing connect

Abstract: An automatic lead advancing mechanism for a mechanical pencil has at its writing point a lead guide tube which is movable axially against a clamping member to cause radially movable components of the clamping member to clamp the lead therein during the writing position of the pencil. The lead guide tube moves axially inwardly against a force exerted by a compression spring interposed between the clamping member and a thrust member, a portion of which is engaged by the lead guide tube and another portion of which has a beveled surface engaging a correspondingly beveled surface on the clamping member. The co-acting beveled surfaces exert both axial and radial forces to the clamping member.

Abstract: A mechanical pencil includes a lead engaging collet biased rearwardly, a collet receiver tube having a tapered guide face and rolling elements mounted between the tapered guide face and the collet for inducing a clamping force against a writing lead. The pencil includes a device for advancing the collet receiver tube and the collet toward a pencil tip and then permitting the collet receiver tube alone to move rearwardly. This assures that the inner elements will step the lead an increment from the pencil tip for writing purposes.

Abstract: A mechanical pencil having a writing point tube slidably mounted on the forward end portion of a pencil casing, an annular slider device slidably mounted within the pencil casing and having a lead retainer, a first spring for urging the writing point tube in the forward direction, a collet chuck mechanism having a lead engaging collet and a chuck-actuation cylinder, a second spring urging both the lead engaging collet and the chuck-actuation cylinder in the opposite direction and a third spring for urging the collet chuck mechanism in the forward direction. The pencil has a locking device for temporarily engaging the slider at its retracted position, and a pusher for releasing the engagement of the slider. When an axial thrust is applied to the writing tip of the pencil for lead advancement, the slider and the collet chuck mechanism as well are retracted within the pencil casing with their positional relation being unchanged.

Abstract: A mechanical pencil includes a removable tubular cover which has functions to protect a tip of the pencil and also to advance automatically the lead therein a tiny increment to project from the pencil tip when it is attached to a rear end of the pencil for writing purposes and to a front end of the pencil after writing is finished.

Abstract: A writing instrument with automatic advancement and feed of successive leads has a housing having a tip part, a lead protecting pipe having an axis and movable in an axial direction, a lead container spaced from the lead protecting pipe in the axial direction, a gripping sleeve extending between the lead container and the lead protecting pipe, a lead clamping member having a plurality of clamping arms and movable between open and closed positions in the axial direction, wherein the clamping arms of said lead clamping member are arranged to abut against the gripping sleeve under a spring action and having a clamping opening with a receiving portion, and the lead clamping member has a shaft connected with said clamping arms with a region adjacent to the latter, and a tilting member provided in the region of the shaft of the clamping member and arranged so that during movement of the lead protecting pipe to the tip part of the housing the tilting member displaces on the shaft of the clamping member, and during m

Abstract: A propelling or automatic writing implement having a lead which can be projected from the implement without pushing. An inner frame having a chuck assembly for permitting advance of the lead but preventing retraction of the lead and a lead protecting tube having a holder for holding the lead with a suitable frictional force are housed in a main body and slidable axially thereof. A mechanism is provided for retracting the frame and the tube by a reaction to which the lead is subjected when pressed against the writing surface with a force of considerable magnitude and for returning them when the lead is released from the force, while permitting the tube to move backward and forward relative to the frame in the course of the reciprocating movement. The lead can be projected by the relative movement of the tube and the frame.

Abstract: Projecting mechanisms for writing elements are actuated by applying pressure to the external casing of the instrument. The writing element is not latched in an exposed condition, therefore the writing element is only exposed when pressure is applied to the casing, as is done when writing with a pen. The projecting mechanism allows for projecting the writing element by applying pressure at substantially any circumferential point along the casing of the pen, or in one embodiment only along the longitudinal portion of the pen closest to the writing end.

Abstract: A mechanical pencil with automatic lead advance in which a slider is temporarily locked at the time when a rearward thrust applied to the pencil tip is released. The slider is locked by an arrangement in which a movable locking tube is disposed around the slider. The locking tube can be inclined relative to the longitudinal axis of the pencil by a spring device so that the slider, when retracted, can be temporarily locked by the inclination of the locking tube.

Abstract: A mechanical pencil with automatic lead feed has a clamping mechanism for clamping a lead in such a manner that it holds the lead steadily against rearward movement but easily permits the lead to move forwardly. A lead tube is fixed at its rear end to the front end of a housing to guide and protect the lead. A sensor is slidably held in the front end of the housing and extends along the lead tube to sense the wear of the lead during writing. A lead advancing mechanism is actuated by the sensor and has a holder for frictionally holding the lead and an elastic member for urging the holder forwardly.

Abstract: A mechanical pencil is of the type in which a writing lead can be advanced by the extent to which the lead has been worn without changing the writing posture of the pencil. The pencil has a lead holder slidably mounted lengthwise within a casing, a lead guide tube slidably mounted within the casing together with the lead holder, a lead feeding device mounted movably within the casing for feeding the lead into the lead guide tube, and a device mounted movably within the casing for locking rearward movement of the lead feeding device. The lead can be advanced by merely releasing a writing pressure which was applied by the writing tip onto a piece of writing paper.

Abstract: A mechanical pencil including a main body divided into first and second members which are rotatable relative to one another. An inner mechanism is provided, primarily in the first member of the body, including a chuck for gripping leads, a chuck tightening member for tightening the chuck disposed around the chuck, a chuck tightening member receiver, and a lead case coupled at a front end portion to the chuck. In a preferred embodiment, a push member is coupled at a front end to the lead case while a spring biases the inner mechanism rearwardly. A mechanism is provided for converting the relative rotation of the first and second members to axial movement of the inner mechanism between retracted and writing positions.

Abstract: This invention relates to a writing implement comprising an outer casing, a coil spring disposed within the casing, an inner tube inserted through the coil spring and having a plurality of presharpened pieces of pencil lead stored therewithin, and a capping member fitted over the open end of the inner tube. The lower (writing) portion of the inner tube is split into two clamping halves. The lower end of the coil spring is formed into a hook which slides along the slot formed between the clamping halves to allow the expelling and feeding of presharpened pieces of pencil lead into the space between said two clamping halves.

Abstract: An automatic pencil which comprises a pointed end cap made of a synthetic resin material into which a lead pushing-out mechanism consisting of a lead chuck fixed to a lead container, a chuck ring externally fitted onto the lead chuck and a spring is inserted, a cushion stopper on the outer periphery of which and at one end thereof engaging projections are integrally formed so as to oppose to a plurality of engaging holes circumferentially provided around an open edge of the pointed end cap, and an outer tube into which the outer periphery of the backward end of the aforesaid pointed end cap is inserted to combine them with each other and, as a consequence, the resultant automatic pencil has a simple construction, so that it can easily be assembled.

Abstract: A mechanical pencil of knocking operated type includes an electrical indicator which provides a visible or audible indication of the presence or absence of a writing lead in the mechanical pencil. A power supply in the form of a cell or storage battery is loaded into a pen body. A first and a second channel are provided which electrically connect the power supply with the indicator. The first channel is associated with one of the poles of the power supply, and is formed by a collet chuck and a lead guide sleeve which are disposed within the pen body in spaced relationship from each other. The second channel is associated with the other pole of the power supply, and includes a switch which is operated in response to a knocking operation which drives the collet chuck. When a writing lead is present between the collet chuck and the lead guide sleeve, the both members are electrically connected together through the lead, whereby the first channel is rendered conductive.

Abstract: A mechanical pencil in which the lead is advanced by squeezing a cylindrical depression member provided at the position of the writer's fingers during normal writing operations. The pencil includes a hollow body with front and rear axial sleeves. A chuck is disposed within the pencil body which has a resiliency which urges the chuck to open outwardly at the front end thereof. A slider including a lead holding member for lightly holding the lead is slidably positioned at the tip of the front axial sleeve. Means is provided for transmitting movement from the depression member, which is formed of a resilient material flush with the cylindrical surface of the pencil body, for transmitting movement from the depression member to the chuck. A lead casing means is disposed in the rear axial sleeve which in some embodiments has the dual function of transmitting movement from a push button provided at the rear of the pencil to the chuck for advancing the lead in a conventional manner.

Abstract: This invention relates to a writing implement comprising an outer casing, a coil spring disposed within the casing, an inner tube inserted through the coil spring and having a plurality of presharpened pieces of pencil lead stored therewithin, and a capping member fitted over the open end of the inner tube. The lower (writing) portion of the inner tube is split into two clamping halves. The lower end of the coil spring is formed into a hook which slides along the slot formed between the clamping halves to allow the expelling and feeding of presharpened pieces of pencil lead into the space between said two clamping halves.

Abstract: A mechanical pencil wherein a lead is propelled through a lead insertion tube provided at the forward end of the pencil body by the propulsion of a lead sustaining and feeding mechanism consisting of a chuck and the like, the mechanical pencil also having a lead protective device wherein a thin film made of an elastic material, such as rubber, synthetic resin or the like, is provided over the whole length of the inner surface of the lead insertion tube so that the lead is permitted to pass therethrough with ease, the elastic thin film being adapted to have a relatively greater thickness at the forward end part of the lead insertion tube so as to form a lead sustaining portion, the elasticity of the lead sustaining portion precluding the lead from slipping out due to own weight when released from the lead sustaining and feeding mechanism thereby minimizing the loss of lead.

Abstract: A mechanical pencil in which a tubular casing is formed with a lead-guiding passage which has a leading end open outwardly away from the casing. A lead is advanced through the passage by a collet movable between a first position in which the lead is clamped and a second position in which the lead is released. An element normally presses the lead, when the latter is in the passage, against an inner surface of the passage for preventing undesirable sliding of the lead along the passage when the collet releases the lead.

Abstract: Mechanical pencil construction wherein the operational movements to advance the lead are accomplished by providing one or more elastically deformable ribs or spring biased cam members that extend outwardly through axial slots in the pencil body in the normal finger gripping area. The radially inward depression of such ribs or cam members by the writer's fingers is converted to axial motion within the pencil, to thereby effect the necessary lead gripping and advancing operations.

Abstract: A mechanical pencil having a main hollow body including a first body member and a second body member with a mouth opening at an end and the first body member being rotatable with respect to the second body member and the first and second body members engaged with each other. A slider is retractable from the opening of the main hollow body and has a lead retainer for frictionally gripping lead and a lead case containing extra leads therein is disposed to the rear and is so biased. A lead gripping chuck is connected at the rear end thereof to said lead case and chuck tightening mechanism receives and tightens the chuck and advancing the chuck relative to the mechanism to supply a new lead having a predetermined length from the opening of the slider. The rotational movement of the first body member is transferred to reciprocating movement of the chuck tightening mechanism so that a new lead is supplied from the opening of the main hollow body by the rotation of the first body member.