Abstract: Knock-out type automatic pencil comprises an outer barrel, an inner tube of plastic material molded integrally with a clamp and a head, a stopper collar inside the front end of outer barrel which retains the inner tube, a press device at the rear end of the outer barrel having lead sharpening and erasing means provided. The clamp at the front end of inner tube is formed in a closed type with slots on it instead of the conventional claw type.

Abstract: A mechanical pencil of the type in which a lead is gripped in a collet clamped about the lead by engagement between cooperating conical faces of a clamping ring and respective movable ends of two elongated collet members which form the collet and pass through the ring. The collet members are connected together at their other ends. The pencil is readily disassembled and assembled because the movable ends, when in the clamping position, are shaped to interfit with the bore of the ring, so as to permit passage of the collet through the ring in one angular position of the collet relative to the ring while preventing such passage except for limited axial movement in another angular position. Cooperating guide elements on the collet and ring hold the collet in the another angular position. A tubular closure member is releasably fastened to the barrel, and in the another position the collet can be axially displaced relative to the ring when the closure member is released.

Abstract: A composite writing instrument, in which a mechanical pencil unit of the type from which lead is ejected and a ball point pen unit are mutually diametrically opposed and held together within a lower tubular casing. A cap is provided accommodating a mechanism for engaging these units to shift them alternately in the axial direction when the cap is rotated around the axis, whereby the units are alternately advanced through a mouth of the writing tip of the lower tubular casing to a writing position or retracted therethrough to a storage position within said lower tubular casing. The mechanical pencil unit is so constructed that the cap is shiftable within certain limits in the axial direction relative to the lower tubular casing when the mechanical pencil unit is in the writing position, whereby the lead of the pencil unit is fed, whereas the cap is nonshiftably locked relative to the lower tubular casing when the ball point pen unit is in the writing position.

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 leads stored therewithin, and a capping member inserted over the open end of the inner tube. The front (writing) end of the inner tube is split into two clamping halves. The front end of the coil spring is formed into a hooked portion which slides along the slot formed between the clamping halves to allow the expelling and feeding of presharpened lead pieces into the clamping halves.

Abstract: A tip-pushed type mechanical pencil permits a forward advance of a pencil lead by pressing the front end of the pencil against a writing surface and then releasing it. The mechanical pencil includes an outer cylinder in which an inner cylinder having a ferrule is fitted. The inner cylinder is normally urged by a first spring to cause the ferrule to project out of the front end of the outer cylinder. A control tube carrying a lead grasping packing is inserted within the inner cylinder. The control tube is urged toward the front end of the outer cylinder by a second spring. A chuck is received within the control tube, and is integrally connected with a lead passage tube which extends through the inner cylinder. The chuck cooperates with a chuck ring disposed within the control tube to grasp or release a lead. Both the chuck and the control tube are urged by a third spring in opposite directions.

Abstract: A lead-feeding mechanism comprising a lead reservoir, a connector, and a chuck in a mechanical pencil is held by a front spring in a normal rear position, at which the chuck is clamping a lead piece, but when a forward shake is imparted to the pencil, a weight collides forwardly with the lead-feeding mechanism and pushes the same forward, counter to the force of the spring, whereupon the chuck feeds the lead piece through a specific distance then releases the same, the lead-feeding mechanism being subsequently returned by the spring to the normal position, where the chuck again clamps the lead piece at a new position thereof.

Abstract: A mechanical pencil with a lead feed, automatically produced by pressure during use of the pencil, comprises a tubular lead magazine closed at an outer end by a removable actuating button and being movably guided in a tubular housing, clamping elements in the housing actuatable by pressure on the actuating button and a lead guide tube projecting from a conical end of the housing and being movable against the pressure of a spring into the latter and carrying at the inner end thereof an entrainment element exerting friction on the lead passing therethrough, in which the clamping elements are movable by means of the actuating button against the force of a second weaker spring and guided by rolling elements along a conical guide face of a clamping cone, which in turn is axially movable between two end positions in the housing.

Abstract: A writing instrument for thin lead refills comprising a housing and a lead feed mechanism located within the housing and wherein the feed of the lead refills is effected by a lead collet slidable axially against a spring force. The housing is sub-divided into front and rear housing sections which are axially adjacent one another and are relatively rotatable about a longitudinal axis of the instrument. To each housing section there is secured in rotation a component of a cam assembly comprising a thrust cam component and a thruster component. Upon relative rotation of the housing sections, the components interact with one another to slide the lead collet into projected open position for receiving a lead refill. One of the cam components is axially secured with the associated housing section and the other cam component is axially secured with the part of the lead feed mechanism carrying the lead collet and is axially displaceble with respect to the associated housing section.

Abstract: An automatic pencil employing axial movement of a lead piece guide and a lead piece chucking mechanism. After a length of protruding lead rod is used up, the lead piece guide is caused to retract in the same amount as the wearing away of the lead rod. By pressing the tip of the lead rod against another object, the lead rod is caused to move back with the chucking mechanism. After the rod is retracted until the tip aligns with the tip of the guide, the rod and lead piece guide will be moved back. The rod will then advance when the holder is moved away from the object while the lead piece guide will be left in the retracted position due to a large friction between the friction member and the guide means. By this operation, the rod is protruded from the guide at substantially equal length to the stroke of the retracting movement.

Abstract: Knock-out type automatic pencil comprises an outer barrel, an inner tube of plastic material molded integrally with a clamp and a head, a stopper collar inside the front end of outer barrel which retains the inner tube, a press device at the rear end of the outer barrel having lead sharpening and erasing means provided. The clamp at the front end of inner tube is formed in a closed type with slots on it instead of the conventional claw type.

Abstract: A mechanical pencil has an axially elongated hollow pencil body in which is slidable a tubular seat member. A lead-protecting sleeve is axially displaceable in the pencil body between a front position and a rear position and is urged into the front position with a relatively strong spring force. At least two jaws are axially displaceable on the seat and are moved radially closer as they move backwardly from the tip so as to grip a lead that projects backwardly from the lead-projecting sleeve. A relatively weak spring urges these jaws backwardly in the seat. An O-ring is provided in the lead-projecting sleeve so that each time the pencil tip is lifted from the writing surface the lead is automatically pulled forwardly by the strong spring force through the jaws. Similarly forward displacement of the seat in which the jaws rest allows for manual advance of a lead gripped by the jaws and passing through the lead-protecting sleeve.

Abstract: A push type mechanical pencil having an inner cylinder made of a synthetic resin including a chuck portion and a spare leads containing tube portion communicating with the chuck portion. An integrally molded inner cylinder unit is provided which has a hollow cylindrical body constituting a part of the spare leads containing tube portion, a plurality of longitudinally extending tube forming members which when they are placed together constitute the remaining part of the spare leads containing tube portion, and a plurality of longitudinally separated chuck members which when they are put together constitute the chuck portion. The tube forming members are integrally connected with each other by means of at least a bendable connector portion, and one of the tube forming members is integral with the hollow cylindrical body. Each of the separate chuck members is integral a corresponding one of the tube forming members.

Abstract: In a push-out type pencil, the lead thereof is extensible by longitudinally sliding the front portion of the pencil relative to the middle portion of the same, said sliding operation being effected in the writing position of hand by retracting said front portion between the extremities of the index and middle fingers to said middle portion clipped fast between the bases of the thumb and index finger adjacent to the web of hand and held stationary against the retracting movement of said front portion.

Abstract: An automatic pencil apparatus for use with an automated drafting system comprises a gripping mechanism for releasably gripping a lead and comprised of a cylindrical tube, and a collet mounted for longitudinal movement in the tube for gripping and releasing the lead. A driving mechanism including an electromagnet selectively drives the gripping mechanism to actuate the collet and release the lead so that a drawing operation can be carried out. A pneumatic cylinder applies a predetermined constant pressure to the lead while in its released state thereby pressing the lead into contact with a drafting paper under constant pressure so that high quality lines can be drawn throughout consumption of the lead and independent of lead wear.

Abstract: A push-button type automatic pencil includes an outer tubular member which is held in the hand of the user and lead rod holding means for holding the lead rod. A lead rod stepping means of a push button type is provided and the lead rod holding means is mounted within the outer member in such a way that the lead rod holding means is movable relative to the outer member, while still holding the lead rod, when the lead rod is pushed backward relative to the outer member. Accordingly, the breaking of the lead rod while writing is eliminated, and a soft writing feel is achieved.

Abstract: A mechanical pencil of the collet-action type is provided with a collet member formed of a pair of identically configured mating half shells guiding and clamping the lead. The half shells are maintained in fixed relation with respect to one another by means of an annulus cooperating with a conically flared portion formed at one end of the collet member, whose diameter is partially reduced corresponding to the inner diameter of the annulus, and by means of a cap at the opposite end of the collet member. The parts are assembled by first sliding one and then the other one of the two collet shells through the annulus into mating relation with one another and thereafter fitting the end cap over the end of the mating shells. All parts of the pencil are maintained in assembled relation by a compression spring.