Abstract: A side knock type mechanical pencil includes a knock button, a barrel, an intermediate lead tube, and a clip. A fixed hole is formed in the side wall of the front end of the barrel, and a rib groove is formed in the inner front side of the fixed hole. At least one button groove is formed in the front end of the knock button, and at least one protrusion or bump with an inclined plane is formed at the lower side of the rear end of the side button. A shaft is formed by the engagement of the button groove of the front end of the button with the rib groove of the fixed hole. At least one circular bulge which is adapted to engage with the protrusion or bump with the inclined plane is disposed on the side of the intermediate lead tube.

Abstract: In a stick-shaped material propelling container capable of propelling and retracting a stick-shaped material, the influence of variation of the dimension of the stick-shaped material can be made small. An inner barrel is slidably inserted in an outer barrel, an elastic body which urges the inner barrel rearward is provided between the inner barrel and the outer barrel, a chuck piece which holds a stick-shaped material is provided at a tip end portion of the inner barrel, and a chuck ring is inserted between the chuck piece and the outer barrel. A cross section of the stick-shaped material forms a triangular shape, the frictional force applying part which is in contact with the stick-shaped material to apply a frictional force is formed on an inner peripheral surface of the outer barrel, and the frictional force applying part abuts on a side in the vicinity of a vertex of the stick-shaped material in a cross section of the stick-shaped material.

Abstract: A tubular holder includes: a tubular wall defining a hollow space adapted to receive an object, and having axially opposite rear and front open ends, and a through hole extending through the tubular wall between the rear and front open ends; a clamp disposed at an outer side of the tubular wall and having a resilient claw extending into the hollow space through the through hole; and a push member disposed movably in the hollow space for pushing the object forward and having a stop face on an outer surface of the push member, the stop face being able to abut against a free end of the resilient claw to prevent rearward movement of the push member so that the push member can move only in a forward direction.

Abstract: The instant invention is a mechanical pencil. The pencil includes a body having a cavity and a lead holding mechanism located in the cavity. The lead holding mechanism includes a pair of arms joined together by a bridge. Each arm terminates with a pair of fingers. The fingers close together when the lead holding mechanism is recessed into the cavity. The fingers open when the lead holding mechanism is advanced out of the cavity.

Abstract: An automatic pencil includes a pencil tube unit, a pencil tip unit, a press cap and an eraser unit. The pencil tube unit includes an external tube member and a pencil refill tube member contained in the external tube member and having a clamping portion for clamping the pencil refill. The pencil tip unit is connected to the external tube member and includes a retainer connected to the clamping portion in the pencil refill tube member and a pencil refill guide tube situated at a conical tip of the conical body and connected to the retainer to guide the pencil refill. The press cap is installed at the pencil refill tube member, and a protrusion is formed along its axis. The eraser unit includes an eraser and at least one spare eraser, both having a surface and a concave hole for connecting the protrusion of the press cap.

Abstract: A writing instrument that includes a tubular body extending along a longitudinal axis between a rear end and a front end provided with an opening through which a writing tip is capable of protruding, a lateral button having at least one actuation face oriented radially outward and at least one first cam arranged inside the body, and a writing tip advancing mechanism that include a movable member movable in a longitudinal direction in the body. The movable member includes at least a first ramp inclined relative to the longitudinal axis, the lateral button is capable of remaining in a rest position in which the first cam is facing the first ramp, and the lateral button is capable of making a first tilting movement toward the inside of the body during which the first cam interacts with the first ramp and the movable member makes a first movement.

Abstract: A writing instrument is capable of functioning both as an automatic mechanical pencil and as a shaking-type mechanical pencil. The writing instrument has a barrel cylinder constituted by a front cylinder detachably connected to a rear cylinder. A slider is disposed at the front end of the barrel cylinder, and a lead chuck, such as a ball chuck, is disposed rearwardly of the slider. A slider spring urges the slider forward and urges the lead chuck rearward. A lead reservoir is movably disposed rearwardly of the lead chuck. Around the outer periphery of the lead reservoir, a weight is disposed to undergo back-and-forth movement in an axial direction. On the outer periphery of the lead reservoir is disposed a weight-receiving cylinder against which the rear end of the weight abuts when the writing instrument is shaken. A knocking spring urges the weight-receiving cylinder forward and urges the lead reservoir rearward.

Abstract: The lead propelling device of the invention is a lead propelling device having a structure for gripping and releasing the lead by a lead gripping mechanism by knocking operation, not transmitting the knocking force to the lead gripping mechanism in knock forward operation, wherein a stopper not allowing the lead to pass by its own weight interlocks with the knock operation, the lead abuts against the stopper rear end upon release of the lead, the lead is inserted into the stopper after gripping the lead in knock backward operation, thereby propelling the lead, and therefore after the knock operation part advances by a predetermined distance, the lead gripping mechanism clears gripping of the lead, and when the lead gripping mechanism grips the lead in the backward stroke of the knock operation part, the knock operation part is set to be movable backward further by a predetermined distance.

Abstract: A safety chalk holder consisting of a chalk holding member received within the bore of a housing, a closed end of the chalk holding member projecting from one end of the housing, a collet end of the holder projectable into and out of the other end of the housing, a chalk receivable into the holder having a cross section dimensioned to cooperate with the collet such that when the collet end of the holder is positioned exterior of the housing, the chalk can be freely received within the collet, spring means urging the collet to be withdrawn into the housing, the collet effective to engage the housing to reduce the dimension of the collet to grasp the chalk as the collet is drawn into the holder, the holder and housing having a locked together connection permitting limited movement of the holder with respect to the housing, but preventing withdrawal of the entirety of the holder from the housing, and a child-proof cap closing the collet projecting end of the housing.

Abstract: An automatic pencil assembly includes a barrel, a point, an urging member, two clamping members, a slide, a guide pipe, a lead, a cap, and a push member. Thus, the lead is pressed downward by the first plug or second plug of the push member to overcome the holding force of the clamping members, so that the lead is inserted into and protruded outward from the slide easily and conveniently.

Abstract: A mechanical pencil, includes an external cylinder, a lead delivery mechanism disposed in the external cylinder, the lead delivery mechanism having a lead-fastening chuck which fastens a lead and moves back and forth in the external cylinder to deliver the lead toward a front end of the external cylinder, a lead holder disposed before the lead delivery mechanism in the external cylinder to gently hold a lead, and a guide member arranged between the lead-fastening chuck and the lead holder in the external cylinder and always urged backwardly toward the lead-fastening chuck to protect a lead portion between the lead-fastening chuck and a lead holding portion of the lead holder.

Abstract: A double-chuck mechanical pencil has an outer tube, a tip fitting provided in the front of the outer tube, a tip chuck located at the tip of the tip fitting for holding a writing substance (e.g., a lead) and urged rearward in the axial directed, and a delivery chuck for delivering the lead. At least one of the tip chuck and the delivery chuck is formed of a synthetic resin material including polyoxymethylene.

Abstract: A double-chuck mechanical pencil has an outer tube, a tip fitting provided in the front of the outer tube, a tip chuck located at the tip of the tip fitting for holding a writing substance (e.g., a lead) and urged rearward in the axial directed, and a delivery chuck for delivering the lead. At least one of the tip chuck and the delivery chuck is formed of a synthetic resin material including polyoxymethylene.

Abstract: A press type mechanical pencil includes an upper barrel, a press device, a refill tube, an abutting rod, a clamp/release device and a lower barrel. An insert post of the clamp/release device has a top portion connected to the abutting rod which is centrally provided with a refill hole for passage of refills. A refill tube is disposed between the abutting rod and the press device. A storage tube has a tube chamber for receiving a plurality of refills, and an open end connected to a tube plug. The tube plug is adapted to guide the refills and for connection with the abutting rod. A neck hole therein provides passage for only one refill through the refill hole into the clamp/release device.

Abstract: A side-knock type mechanical pencil comprising a barrel having an opening in a side wall, a chuck mechanism housed in the forepart of the barrel, a slider moved back and forth within the barrel to open and close the chuck mechanism, a knock lever which is inserted into the opening with an upper front end pivotally mounted with respect to the barrel, a lower front end thereof being placed in contact with the slider, and a resilient member for holding the knock lever in an initial position.

Abstract: A double-chuck mechanical pencil has an outer tube, a tip fitting provided in the front of the outer tube, a tip chuck located at the tip of the tip fitting for holding a writing substance (e.g., a lead) and urged rearward in the axial directed, and a delivery chuck for delivering the lead. At least one of the tip chuck and the delivery chuck is formed of a synthetic resin material including polyoxymethylene.

Abstract: A stick-shaped material propelling container comprised of a flat-shaped outer sleeve, a chuck in the form of tweezers having a pair of opposing flat arms inserted into the outer sleeve and having a base in the rear portion thereof, and a chuck ring connected to the front portion of the outer sleeve and positioned around the front portion of the chuck. A through hole is formed through the base of the chuck in a direction perpendicular to a longitudinal direction thereof, and a retaining portion is formed on an inner surface of the outer sleeve. An elastic member is mounted between the rear inner surface of the through hole and the retaining portion of the chuck.

Abstract: A longitudinal opening window (1B) is formed a: a rear end portion of a cylindrical casing (1) of a mechanical pencil. At the rear end of the cylindrical casing (1), an eraser holder (12) is disposed in such a way that it can move forward and rearward for a predetermined distance. At the rear end of the eraser holder (12), a rubber eraser (13) is mounted. At the front of the eraser holder (12), a cylindrical small diameter front portion (12B) is provided. On the outside of the small diameter front portion (12B) is disposed a stop portion (12D) protruding outwardly on a resilient piece (12C). The stop portion (12D) engages with the opening window (1B). The rear end of a lead reservoir (10) connected to the rear portion of a chuck (7) extends to the inside of the small diameter front portion (12B). When the cylindrical casing (1) is shaken, a weight (11) surrounding the lead reservoir (10) moves forward, thereby causing the chuck (7) to move forward.

Abstract: A push-type writing instrument, particularly a pencil, includes a retaining collar downwardly protruded from a pair of radially opposed fingers provided on a tapered forward portion of an outer body in which a lead is retained, having two arm members with each arm member connected between the retaining collar and each finger for suspending the retainer collar under the pair of opposed fingers to prevent loss of resilience of the two fingers due to fatigue failure when frictionally holding the lead between the two fingers for a long time service.

Abstract: A retractable, refillable, sharpen-free pencil assembly comprises an outer tube, an inner tube and several sections of pre-sharpened leads. The inner tube is movable relative to the outer tube. An upper half portion of the inner tube is enlarged by fitting a squeezing tube such that a spring can be positioned below the squeezing tube. When the inner tube is shifted, a lower portion of a spring pushes a lowest lead to a chucking device by which the lead is tightly gripped. A push plate attached to the slot of the outer tube has a squeezing portion engaged with the last coil of the spring. Sliding the push plate upward can pull the lower portion of the spring out of the inner tube. The propelled lead can be retracted into the inner tube and the inner tube can be pulled back and enclosed completely by the outer tube.

Abstract: An automatic pencil for automatically dispensing a writing lead comprises a hollow, longitudinal main body for receiving therein lead, and a mouthpiece detachably connected at its rear end to a front end of the main body for projecting a top of the lead received in the main body from a front end of the mouthpiece. A slider is movably disposed in a front portion of the mouthpiece for frictionally holding therein the lead, the slider being manually, reciprocally moveable in the axial direction of the pencil in response to writing pressure applied thereto during use of the pencil. A chuck is mounted in a rear portion of the mouthpiece for releasably clamping the lead during use of the pencil such that the chuck operates in response to the reciprocating movement of the slider to allow advancing movement of the lead toward the front end of the mouthpiece and to prevent retracting movement of the lead.

Abstract: A writing apparatus with retractable presharpened pencil lead elements is disclosed having an outer pen holder, an inner cylinder slidably mounted within the outer pen holder, a compression spring to bias the inner cylinder toward an end of the outer pen holder, a pencil lead pushing mechanism to push the lowest pencil lead out of the inner cylinder, a pencil lead clamping mechanism to retain the lowest pencil lead extended beyond the inner cylinder, and a sliding retractor to push away an elastic hook of the pencil lead pushing mechanism in order to retract the extended pencil lead into the inner cylinder. The inner cylinder has a conical flange projected radially to retain the sliding retractor when the elastic hook is pushed away so as to restrain displacement of the inner cylinder and the pencil lead can be retracted into the inner cylinder first.

Abstract: A knocking type solid cosmetics container which comprises a container main body 1 comprising; a cylindrical pushrod housing pipe 6 inserted in the container main body 1; a delivery chuck 9 fixedly provided on a front end of the pushrod housing pipe 6, a pushrod 3 inserted into the pushrod housing pipe 6 and the delivery chuck 8; a tubular cartridge 2; and a piston 16 contained in the cartridge 2.

Abstract: In a mechanical pencil, a tubular lead reservoir is connected to the rearward end of a lead chuck. A cylindrical weight is fitted slidably around the lead reservoir and is adapted to strike against the chuck to open the same to allow forward feed of the lead when a forward shake is applied to the pen barrel. In order to prevent forward feed of the lead as a result of unintended forward shake while carrying the pencil, a slider disposed rearwardly of the lead reservoir has a radially outwardly extending engagement projection which is adapted to slidably engage either a longitudinal guide slot in the pen barrel or a lateral slot circumferentially and rearwardly extending in the pen barrel. When the engagement projection is in engagement with the lateral slot, the chuck is caused to take an advanced position in which the chuck is open so that a forward stroke cannot feed the lead forward.

Abstract: A container for extending a stick-shaped material comprises a tubular body and a chuck formed on the tubular body inserted into a chuck ring. The tubular body and the chuck ring are provided with first and second deflectable projecting parts respectively, while a head member is provided with first and second retaining holes the first deflectable projections of the tubular body engage the first retaining holes, while the second deflectable projecting parts of the chuck ring engage the second retaining holes of the head member. A resilient elastic body is mounted between the end of the head member and an elastic body bearing formed on the tubular body. A stick-shaped material such as a stick-shaped eraser is held in the head member and the chuck. The tubular member, the chuck ring, the stick-shaped material and the elastic body are assembled as a unit with the head member. Therefore, the number of parts is reduced and assembly and disassembly becomes relatively easy.

Abstract: A refill lead writing instrument for stepped advancement of a lead has a spring biased clamping device for holding a lead in direction of its longitudinal axis against a writing pressure. The clamping device includes a clamping chuck supported in a clamping sleeve under a spring action and a longitudinally displaceable lead pipe against which the clamping chuck can abut. A gripping part is form-lockingly connected with a shaft so that the shaft and the gripping part are rotatable relative to one another about a common longitudinal axis. The shaft and the gripping part have opening of same diameters and provided with grooves. A longitudinally displaceable supporting pipe has strips guiding in the grooves, one of the grooves having an extension extending in direction of the writing pipe and formed as a recess in which one of the strips is turnable.

Abstract: A side actuated writing implement wherein projections are provided to prevent the wave-shaped actuating member from straightening out.

Abstract: A knock-out type mechanical pencil which comprises a lead containing tube in which the inner and outer walls thereof are so tapered that the lead inlet thereof is larger in diameter than the opposite end thereof. The mechanical pencil further comprises a spring supporting ring interposed between the clamping ring so attached to the outer periphery of a chuck portion integrally formed with the lead guide of the lead containing tube and spiral springs to oppose with the base end of the ferrule within the outer barrel for urging the spring supporting ring to the ferrule. Thus, this mechanical pencil can eliminate the lead jams in the lead containing tube and lead breakage therein.

Abstract: A knock-type propelling pencil includes a lead pipe inserted into an outer cylinder and having a lead chuck at the end portion thereof, a chuck-fastening tube for fastening the lead chuck, a cushion sleeve coming into contact with the chuck-fastening tube and being slidable relative to the outer cylinder, and being urged by a spring. The cushion sleeve has a cushion portion which can be resiliently deformed to absorb excessive writing pressure and thereby preventing breaking of the lead.

Abstract: A mechanical pencil having an automatic lead extending mechanism which has a radially displaceable member disposed on an entire circumference of the pencil body. The lead protrudes from a tip end of the pencil body when the radially displaceable member is radially displaced.

Abstract: A mechanical pencil with a chuck made of plastics includes a lead case connected with the chuck, a ring arranged to surround and hold the chuck, and a spring for biasing the chuck toward a position where it is engaged with the ring, all of which are disposed within a tubular housing. The plastic chuck includes a cylindrical tube connected with the lead case and three elastically deformable extensions integral therewith. Each of these extensions has an engaging portion for grasping a lead and a connecting portion whose inner surface axially forms a curve of secondary degree extending from the cylindrical tube and expanding radially toward the engaging portion in its free state, so that the engaging portion aligns with the lead when it is engaged with the ring. Accordingly, a grasping force is uniformly applied around the lead.

Abstract: A mechanically controlled writing apparatus with presharpened pencil lead elements generally comprises of an inner cylinder and a pen-holder. The inner cylinder is a straight hollow tube, having two elongated piercing grooves vertically made at the bottom to permit the bottom end be slightly expanded for passing therethrough of pencil lead elements, and a plurality of wedge-like projections made on the outer wall surface at the bottom end and respectively reducing upward, which wedge-like projections may be squeezed inward by the inner wall surface of the outer pen-holder to firmly retain the bottom pencil lead element for smooth writing. The pen-holder comprises a reduced bottom end having a hook means integrally made thereon to alternatively insert through the two elongated piercing grooves into the inner cylinder, which hook means may be controlled to displace outward through a lever motion effect.

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: 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 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: 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 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: An automatic pencil with a lead-sharpening device, has a pencil lead of a diameter of 2 mm inserted into the pipe sleeve of the pencil case in which a lead-sharpening knife holder is attached. Whenever the lead becomes dull, the user presses and turns the cap on the top of the pencil and then sharpens the lead by the knife holder to make the lead ready for continued use, and the user can retract the lead back to the pencil case if the pencil is not used to prevent the lead from being broken or damaged.

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 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