Abstract: An image forming apparatus has a chassis, a feed roller rotatably supported by the chassis, a feed roller gear relatively unrotatably coupled to the feed roller, a motor that drives the feed roller, a drive gear that receives driving force from the motor, and an intermediate gear having a gear portion that engages the drive gear and the feed roller gear and an axle portion that is rotatably supported to the chassis via intermediate gear bearings. At least one of the intermediate gear bearings includes a substantially circular inner surface and a stepped portion that is depressed from the circular inner surface. The axle portion of the intermediate gear is supported by the stepped portion while the intermediate gear transmits driving force the motor from the drive gear to the feed roller gear during printing.

Abstract: An image forming apparatus has a chassis; a print head unit pivotably supported by the chassis; a platen roller rotatably supported by the chassis to perform printing with the print head unit; a metal feed roller rotatably supported by the chassis to convey paper; a metal press roller rotatably supported to the chassis so as to be pressed against the feed roller to convey paper; and feed roller bearings mounted to the chassis for rotatably supporting the feed roller. The feed roller bearings have contact parts that project toward the print head unit, such that the contact parts are pressed into contact with the print head unit when the print head unit is pressed against the platen roller during printing. The precision with which paper is fed and printing is performed can be improved.

Abstract: A rotary magnetic head device includes a stationary drum; a rotary drum having a rotary magnetic head; a rotor of a motor fixed to the rotary drum; a support shaft for pivotally supporting the rotary drum, the support shaft having a receiving face; a radial bearing for receiving a radial load, interposed between the rotary drum and the support shaft; a thrust bearing for receiving a thrust load, being slidably put on the receiving face; an urging member for urging the thrust bearing against the receiving face by pushing the rotary drum downward; and a reverse L-shaped support fixed to the stationary drum. The urging member is supported by the reverse L-shaped support and arranged on the rotary drum.

Abstract: The image forming apparatus includes the print unit pivotably supported by the chassis, and the pivoting member rotatably supported by the support rod. The print unit has arm portions and the print head element. One of the arm portions has a downward facing portion. The pivoting member has a first side part configured to receive driving force from the motor in first and second rotational directions, and a second side part relatively unrotatably coupled to the first side part. The first side part is integrally provided with a lifting projection, which is configured to engage the downward facing portion of the print unit from below and move the print unit in a direction away from the platen roller while the pivoting member is pivoted in the first rotational direction. It is possible to reduce the number of members for moving the print unit away from the platen roller.

Abstract: An image forming apparatus has a chassis, a roller rotatably supported in the chassis, a motor for driving the roller in either of first and second rotational directions, a motive gear that receives driving force from the motor, a driven gear that meshes with the motive gear, and a pivot arm that is pivotably mounted on the motive gear and has an axle that rotatably supports the driven gear via a coil spring. The inner peripheral portion of the coil spring engages a first holder formed on the driven gear, while the outer peripheral portion of the coil spring engages a second holder formed on the pivot arm. It is possible to use a coil spring to pivot a pivot arm without increasing the number of components or the time required for assembly.

Abstract: An image forming apparatus includes a chassis, a motor, a drive transmission gear that receives rotational force from the motor, a feed roller rotatably supported by the chassis, an intermediate gear that has a circular bearing, receives rotational force from the drive transmission gear, and transmits rotational force to the feed roller gear, and a gear support axle that is inserted through the bearing of the intermediate gear for rotatably supporting the intermediate gear. The gear support axle is provided with a bearing engagement part. The bearing engagement part has at least one flat section, at least one circular section, and at least two support portions formed between the flat section and the circular section, such that the gear support axle is supported by the bearing at at least one of the two support portions.

Abstract: The image forming apparatus has a chassis, a feed roller rotatably supported by the chassis to convey paper in a paper supply direction with a first load, a press roller rotatably supported by the chassis to press on the feed roller with a predetermined pressing force, and feed roller bearings coupled to the chassis for rotatably supporting the feed roller. The feed roller bearing has an arc shaped feed roller support surface that supports the feed roller. The inner diameter of the feed roller support surface is substantially equal to an outer diameter of the feed roller. A paper ejection direction end of the feed roller support surface is positioned such that a moment on the paper ejection direction end generated by the pressing force of the press roller is no less than a moment on the paper ejection direction end generated by the first load of the paper.

Abstract: The image forming apparatus includes a chassis, a feed roller, and a press roller. The chassis includes first and side surfaces, a bottom surface that connects the first and second side surfaces, and a curved part formed unitarily with the bottom surface. The curved part has a feed roller bearing support portion. The feed roller is rotatably supported between the first and second side surfaces via feed roller support bearings for conveying paper. The feed roller bearing support portion of the curved part supports one of the feed roller support bearings. The press roller is rotatably supported between the first and second side surfaces for pressing on the feed roller. The feed roller has a paper conveying portion that has a plurality of projecting portions. A widthwise center of the paper conveying portion substantially matches with a widthwise center between the pair of feed roller bearings.

Abstract: An image forming apparatus has a chassis, a head portion pivotably supported on the chassis, a platen roller rotatably supported on the chassis opposite the head portion, a plurality of elastically deformable support rods supported on the chassis, a U-shaped rotary member pivotably supported to the chassis by unrotatably engaging the support rods, and a drive mechanism. The rotary member has a first side arm, a second side arm, and a linking section for linking the first side arm and the second side arm. The second side arm is configured to press the head portion against the platen roller with an urging force of the support rods. The drive mechanism is engaged with the first side arm of the rotary member to pivot the rotary member around the support rods.

Abstract: A thermal printer includes a main frame having side plates, a platen roller rotatably supported in the main frame, a print head unit supported in the main unit so as to be pivotable between an image-forming state and a non-image forming state, a sheet case adapted to accommodate a sheet, and a contact portion that is attached to the print head unit so as to pivot together with the print head unit. The print head unit is pressed against the platen roller to convey a sheet therebetween when the print head unit is in the image-forming state. The sheet case is mounted in the main frame through an insertion part formed in one of the side plates. The contact portion contacts the sheet case from a second side plate side when the print head unit is in the image-forming state. It is possible to reduce the occurrence of printing defects.

Abstract: The image forming apparatus has a frame, a head portion pivotably supported on the frame, a platen roller supported on the frame opposite the head portion, an elastic support rod supported on the frame, a rotary member pivotably supported by the support rod and having a pressing member, and a drive mechanism engaged with the rotary member to pivot the rotary member around the support rod. The pressing member presses the head portion against the platen roller with the urging force of the support rod. The image forming apparatus is structured with members that are easy to manufacture.

Abstract: An FM detector circuit includes a bridge circuit having four sections with a discriminator connected as one of the four sections. An FM intermediate frequency is applied across one pair of diagonally opposed nodes of the bridge circuit and an output is picked up across the other pair of diagonally opposed nodes of the bridge circuit. The discriminator includes a piezoelectric material that is selected to produce stable overall temperature characteristics.

Abstract: In a thermally transcribing printer including a frame, a roller made of a metal for feeding sheet at constant speed, a gear made of a resin, a motor, a press-fit engaging member, and a compression coil spring, the roller includes a shaft portion attached to project from an inner side to an outer side of the frame 1 and the press-fit engaging member is press-fitted to the shaft portion. Further, the gear includes a shaft inserting hole in a circular shape inserted from an outer side of the press-fitted engaging member made of a metal into a shaft portion of the roller, and four second engaging portions provided at intervals of 90 degrees between the shaft inserting hole and an outer peripheral portion of the gear and having a predetermined length in a rotational direction.

Abstract: It is a drive transmission mechanism for a printer apparatus, which has a conveying roller gear connected to a conveying roller, an intermediate gear including a small-diameter intermediate gear portion for rotating the conveying roller gear, and an intermediate gear supporting shaft rotatably supporting a shaft insertion hole of the intermediate gear. In this mechanism, the conveying roller gear includes a conveying roller gear circular portion having a diameter that is substantially equal to the reference pitch circle diameter of the conveying roller gear. The intermediate gear includes a small-diameter intermediate gear circular portion having a diameter that is substantially equal to the reference pitch circle diameter of a small-diameter intermediate gear portion. Further, the intermediate supporting shaft is mounted therein in such a manner as to provide a predetermined fitting clearance between the intermediate supporting shaft and the shaft insertion hole.

Abstract: In a thermally transcribing printer including a frame, a roller shaft, a roller shaft drive gear and a motor, the roller shaft includes one end installed on an inner side of the frame and folded to bend in an L-like shape and other end fitted to a drawout preventing portion in a recess shape of the frame. The roller shaft drive gear includes a hook portion attached to the one end of the roller shaft, engaged with a portion of the roller shaft other than the fold-bend portion disposed a vicinity of the one end of the roller shaft and having an opening width smaller than a diameter of the roller shaft for restraining the roller shaft from being detached in the bended direction, and a pair of rotation preventing ribs for holding to squeeze the fold-bend portion of the roller shaft.

Abstract: The thermal-transfer printer includes: a main body frame 10; a platen roller 20; a thermal head 31; a pair of head supporting arms 33 (head attaching arms 32); and a pressing member 40 for pivoting the head supporting arms 33 (head attaching arms 32) to a side of the platen roller 20. The pressing member 40 includes a first pressing arm 41 and a second pressing arm 42, and a connecting member 43 having two of a first bending portion 43a and a second bending portion 43b in an L-lettered shape. The first pressing arm 41 includes: a recess portion 41a; a supporting shaft portion 41b; a first notch portion 41c; and a drawout preventing portion 41d. The second pressing arm 42 includes: a recess portion 42a; a supporting shaft portion 42c; and a second notch portion 42d.

Abstract: The thermal-transfer printer includes: a pair of head attaching arms 12 having fitting holes 12c respectively inserted with support shafts 9 and having center lines inclined to axis lines of the supporting shafts 9 by a predetermined inclination angle; and supporting shaft attaching portions 12b being bent by bending lines 12d that intersects with a line connecting the fitting holes 12c and a printing position of a thermal head 11 relative to a sheet 100. The fitting hole 12c of respective supporting shaft attaching portion 12b are attached to the supporting shafts 9 in a state of being elastically bent in directions opposed to each other such that predetermined inclination angles of the supporting shafts 9 of center lines of the fitting hole 12c of the supporting shaft attaching portion 12b relative to axis lines of the supporting shafts 9 are reduced.

Abstract: An idler mechanism for a magnetic tape device. An idler gear is swingingly displaced between first and second positions to selectively transmit rotation to one of a pair of reels. One end of an arm-like swinging member is coupled in a relatively rotatable manner to a center shaft of an input gear which always meshes with the idler gear and which is rotated forwardly and reversely. A shaft which is disposed on the other end of the swinging member is inserted in a relatively rotatable manner into a bearing hole of the idler gear. A surface of a flange which is disposed on the input gear is formed as a friction force applying face which extends radially outwardly so as to be inclined downwardly. An outer peripheral portion of the idler gear slidably comes into contact with the friction force applying face.

Abstract: In a magnetic tape device, a recessed groove 41 protruding from a moving table. A press spring 16 engaged with the lever 8 is pressed against the rod 5. The table is slightly pushed-in in a backward motion b direction by inserting a tape cassette to the table which is on standby at a cassette inserting position. When the pushing is detected and a driving source is activated, the lever 8 is swung backward (d), whereby the moving table is moved backward (b) via the rod 5 to a cassette placing position. A cam 42 is formed in the groove 41, and when the moving table is pushed-in from the cassette inserting position in the backward motion b direction, the rod 5 is transferred onto the cam 42 to increase the pressing force of the spring 16.

Abstract: In a sheet feeder of the present invention, a groove-shaped concave provided on an inner surface of a bearing extends therethrough in a direction where a rotational shaft of a feed roller extends. A surface of the rotational shaft of the feed roller is supported on a pair of outer edges of the groove-shaped concave formed on the inner surface of the bearing. A bottom of the groove-shaped concave is substantially circular-arc and concentric with the inner surface of the bearing other than the groove-shaped concave. The bottom of the groove-shaped concave is formed at such a depth that the surface of the rotational shaft of the feed roller does not contact the bottom while the rotational shaft of the feed roller is supported on the outer edges of the groove-shaped concave.