Patents Assigned to CITIZEN MACHINERY CO., LTD.
  • Patent number: 11975414
    Abstract: A tool rest has a base, a tool holder rotatably supported on the base, and rotatably holding a tool, a rotational mechanism rotating the tool holder, a plurality of flexible linear members in which one ends of the plurality of linear members are connected with the tool holder and a winding device connected with the other ends of the plurality of linear members, and winding up the plurality of linear members by rotating when the tool holder is rotated by the rotational mechanism.
    Type: Grant
    Filed: August 21, 2019
    Date of Patent: May 7, 2024
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventor: Kyota Kotake
  • Patent number: 11919093
    Abstract: A machine tool includes a plurality of modules, and a control means for controlling operation of the modules, wherein the plurality of modules include a fixed module and two movable modules. The control means includes a restriction means for restricting the movement of the two movable modules for allowing only one of the movable modules to be moved to a facing position facing the fixed module; and a determination means for determining the movable module to be moved to the facing position. The control means is configured to control the operation of the plurality of modules so that, when the operation under cooperation of the fixed module and one of the movable modules has been completed, the restriction means releases the restriction of the movement of the other movable module to the facing position.
    Type: Grant
    Filed: September 24, 2019
    Date of Patent: March 5, 2024
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventor: Shuichi Watabe
  • Publication number: 20230294227
    Abstract: A tooling exchange mechanism and a machine tool having the tooling exchange mechanism, in which a load applied to a turret is reduced when exchanging a tooling in the machine tool, are provided with a pressing member 210 of a tooling detachment unit 200 that presses the rear end of a tooling holding unit 100 to be able to release the retracted state of a tool holder Th of a tooling T by a tool holder holding portion 150 of the tooling holding unit 100, and a locking lever 220 of the tooling detachment unit 200 engageable with an engaging projection 112a formed on the rear end side of the tooling holding unit 100.
    Type: Application
    Filed: September 30, 2021
    Publication date: September 21, 2023
    Applicants: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Atsushi AOYAGI, Kazutoshi KITAZAWA
  • Publication number: 20230050486
    Abstract: A machining device threads a workpiece by relatively rotating the workpiece and a multi-blade tool and relatively moving them along a feed direction to perform cutting processes in the radial direction of the workpiece along the same cutting path in a predetermined spiral form. A controller performs a groove machining to form a threaded portion with vibration in the radial direction of the workpiece and a finish machining to form the threaded portion by bringing the multi-blade tool into contact with the grooved portion of the workpiece. The multi-blade tool has a first cutting blade and a second cutting blade arranged side by side along the feed direction. The controller sets amplitude of a vibration waveform to a value at which a cutting edge of the second cutting blade does not come into contact with the screw bottom surface of the workpiece in the finish machining.
    Type: Application
    Filed: November 30, 2020
    Publication date: February 16, 2023
    Applicants: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Kazuhiko SANNOMIYA, Shinichi MUTOU
  • Patent number: 11554420
    Abstract: Disclosed are threading device and threading method, including a turning step for threading a rotating workpiece with a predetermined cutting depth, by relatively moving a tool in the axial direction of the workpiece and then rounding-up the workpiece obliquely by relatively moving the tool in the axial direction and radially outward. The workpiece is subjected to the threading process by repeatedly carrying out the turning step while sequentially shifting the axial position for starting the rounding-up of the workpiece relative to an axial position where the rounding-up of the workpiece has been started in a previous turning step.
    Type: Grant
    Filed: June 21, 2018
    Date of Patent: January 17, 2023
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Hikaru Takahashi, Tamotsu Katsuta
  • Patent number: 11517991
    Abstract: A machine tool includes: a cutting tool; rotating means; feeding means; and vibration means for reciprocatingly vibrating the cutting tool and the workpiece relative to each other; wherein the cutting process is carried out by a relative rotation of the workpiece and the cutting tool, and feeding of the cutting tool, to thereby move the cutting tool continuously along a plurality of predetermined movement paths each having a different machining feeding direction. The machine tool further includes vibration restriction means that operates as the movement of the cutting tool changes from one movement path of two consecutive movement paths to the other movement path, for restricting the reciprocating vibration for a predetermined period from the movement starting position of the movement paths, and starting the reciprocating vibration after the lapse of said predetermined period.
    Type: Grant
    Filed: October 4, 2018
    Date of Patent: December 6, 2022
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Takaichi Nakaya, Kazuhiko Sannomiya, Hiroshi Shinohara
  • Patent number: 11517990
    Abstract: A machine tool (1) includes a spindle (32) supported on a support surface (37a) of a support body (37) with such an orientation that the longitudinal axis of the spindle extends along the support surface (37a). The spindle (32) is movable in a vertical direction that is perpendicular to the longitudinal axis of the spindle (32). The support body (37) is provided with a ventilation hole (80) extending through the support body (37) between the support surface (37a) and a surface (37b) facing in the direction opposite to the support surface (37a), to open toward the spindle (32).
    Type: Grant
    Filed: October 3, 2018
    Date of Patent: December 6, 2022
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Koichi Yabe, Yosuke Ando, Yosuke Wada, Wataru Katagishi
  • Publication number: 20220355390
    Abstract: A chuck device for holding a plate material workpiece supplied to a machine tool without deforming the workpiece is provided. A housing has a workpiece contact surface arranged to face workpiece holding claws, and when holding of a workpiece is released, a plurality of rods integrally swings so that the workpiece holding claws are moved away from the workpiece contact surface of the housing and moved away from each other, and when holding the workpiece, after the plurality of rods integrally swing so that the workpiece holding claws are brought close to the workpiece contact surface of the housing and brought close to each other, the plurality of rods moves integrally in parallel with the forward/backward moving direction of a drive body to bring the workpiece holding claws into contact with the workpiece.
    Type: Application
    Filed: November 6, 2020
    Publication date: November 10, 2022
    Applicants: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Sakae NAKAZAWA, Masao SAKAI
  • Patent number: 11491548
    Abstract: The machine tool includes modules and a control portion. Each of the modules includes a main spindle for holding a workpiece and a tool post for holding a tool. The tool is used to machine the workpiece held by the main spindle. The control portion is configured to control to restrict a parallel execution of predetermined machining for the workpiece and machining affected by the predetermined machining and to permit an execution of machining other than the restricted machining.
    Type: Grant
    Filed: September 6, 2018
    Date of Patent: November 8, 2022
    Assignees: Citizen Watch Co., Ltd., Citizen Machinery Co., Ltd.
    Inventor: Shozen Yanakawa
  • Patent number: 11484947
    Abstract: A machine tool includes a spindle headstock having a main spindle, a spindle headstock having a main spindle with a Z3 axis parallel to an axis center direction of the main spindle, a turret that moves relative to the spindle headstocks, and a controller that superposition-controls the spindle headstock with movement of the turret as a standard, wherein the turret is movable in directions of an X axis and a Ys axis that are orthogonal to a Z axis and intersect with the Z axis at an angle except for the right angle, and the controller moves the turret in a direction of a Y axis different from the Ys axis and the X axis by combining movement in the direction of the Ys axis and movement in the direction of the Y axis, and regulates, in the superposition control, the movement of the spindle headstock in the X axis direction associated with the movement in the Y axis direction.
    Type: Grant
    Filed: September 10, 2018
    Date of Patent: November 1, 2022
    Assignees: Citizen Watch Co., Ltd., Citizen Machinery Co., Ltd.
    Inventors: Takanori Shinohara, Mitsuru Yamaura
  • Patent number: 11465230
    Abstract: A machine tool includes a first main shaft, a first drive source for moving the first main shaft, a second main shaft, a second drive source for moving the second main shaft, and a control means for carrying out a control so as to bring the workpiece held by the first main shaft and the workpiece held by the second main shaft into contact with each other while rotating them relative to each other, thereby to carry out the friction-heating, and to stop the relative rotation of the pair of workpieces and move only the second main shaft in the axial direction while holding the first main shaft stationary, thereby to carry out friction-welding of the pair of workpieces. The control means controls the operation of the first drive source upon the friction-welding of the pair of workpieces, so as to maintain the axial position of the first main shaft.
    Type: Grant
    Filed: July 16, 2019
    Date of Patent: October 11, 2022
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Takaichi Nakaya, Ai Kikuchi
  • Publication number: 20220314332
    Abstract: A machine tool and a controller for the machine tool that accurately detect a defect in a cutting-off process due to breakage of a cutting-off bit and the like is provided. The machine tool includes: a spindle 110 for holding one end side of a workpiece W; an opposed chuck 131 that is opposed to the spindle 110 and is movable with holding another end side of the workpiece W; and a spindle moving motor 122 for moving the spindle 110. The machine tool or the controller is provided with a load detector 172 for detecting a load of the spindle moving motor 122, and workpiece separation detector 173 for detecting a defect in a cutting-off process from the load in performing a taking out operation.
    Type: Application
    Filed: August 17, 2020
    Publication date: October 6, 2022
    Applicants: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventor: Toshiyuki SUZUKI
  • Patent number: 11446781
    Abstract: A control device for a machine tool and a machine tool capable of easily performing cutting with vibration according to the amount of feed is provided. A control device (180) for a machine tool comprises a control means (181) for controlling the relative rotation and feeding of a cutting tool and a material, the control means performing control such that cutting is performed with vibrating the cutting tool relative to the material by combining a forward feed movement in the machining direction, in which the cutting tool machines the material, and a return movement in the counter-machining direction.
    Type: Grant
    Filed: July 26, 2018
    Date of Patent: September 20, 2022
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Takaichi Nakaya, Hiroshi Shinohara
  • Publication number: 20220234112
    Abstract: A machine tool includes: a joint portion processing control means for controlling the processing of the joint portion in a joined workpiece such that a first workpiece is gripped by a grip section, and a predetermined region extending from a joint portion of a joined workpiece toward a second workpiece is processed over a range of not less than a predetermined width to have an outer diameter of not more than an outer diameter of the first workpiece; and a movement control means for controlling the movement of the joined workpiece so as to slidingly move the joined workpiece relative to the support section, from a state in which the first workpiece is supported by the support section, up to a state in which the second workpiece is supported by the support section.
    Type: Application
    Filed: June 1, 2020
    Publication date: July 28, 2022
    Applicants: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Toshiyuki SUZUKI, Haruhiko MISONO
  • Patent number: 11396052
    Abstract: A turret tool holder includes an engagement means having engaging elements on a turret side and a support base side, a clutch member for transmitting a driving power to a turret drive section, and a moving mechanism. The moving mechanism includes a rotatably supported drive shaft, a first feed screw mechanism and a second feed screw mechanism rotatable in response to the rotational drive of the drive shaft for moving the clutch member and the engagement elements, and a coordination mechanism arranged between the drive shaft and the first feed screw mechanism or the second feed screw mechanism, for moving the engaging elements in response to the rotational drive of the drive shaft, with a feed amount smaller than the feed amount of the clutch member.
    Type: Grant
    Filed: June 13, 2018
    Date of Patent: July 26, 2022
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventor: Noriyoshi Taguchi
  • Publication number: 20220219273
    Abstract: Provided are a coolant supply device and a machine tool in which ejection of a coolant is easily switched on and off. A coolant supply device 10 for supplying a coolant to a workpiece machining area in a machine tool, the coolant supply device comprising: a rotary nozzle 40 formed to have a cylindrical shape and having, at an outer circumferential face thereof having the cylindrical shape, an ejection port 51 for ejecting the coolant; and a supply device body 20 rotatably supporting the rotary nozzle and configured to be capable of supplying the coolant to the rotary nozzle. The supply device body is configured to be capable of switching an ejection allowed range in which the ejection port is opened and an ejection stopped range in which the ejection port is blocked from each other in accordance with rotation of the rotary nozzle.
    Type: Application
    Filed: May 26, 2020
    Publication date: July 14, 2022
    Applicants: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventors: Koichi YABE, Tadayasu SHIDA, Yosuke ANDO, Shinpei KAI
  • Patent number: 11376697
    Abstract: The tool holding device includes: a casing including a first surface, a second surface opposed to the first surface, and a first projection and a second projection projecting opposite to the first surface from the second surface; a first tool holding part disposed on the first surface at a position opposed to the first projection; a second tool holding part disposed on the first surface at a position opposed to the second projection; a driving-force input unit disposed at the end of the first projection and rotated by driving force being inputted; a first shaft extending in an axial direction perpendicular to the first surface and the second surface, the driving-force input unit and the first tool holding part being disposed at one end and the other end of the first shaft, respectively; a second shaft extending in the axial direction and having one end housed in the second projection, the second tool holding part being disposed at the other end of the second shaft; and a rotation transmitting unit rotating th
    Type: Grant
    Filed: July 6, 2018
    Date of Patent: July 5, 2022
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventor: Kyota Kotake
  • Publication number: 20220161339
    Abstract: A machine tool and a control device for the machine tool for shortening the machining time of a workpiece in a case where the relative and reciprocal vibration of workpiece holder and tool post in the radial direction of the workpiece is stopped during a period from an initial point until when the workpiece and the cutting tool come into contact with each other is provided.
    Type: Application
    Filed: May 22, 2020
    Publication date: May 26, 2022
    Applicants: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventor: Kazuhiko SANNOMIYA
  • Patent number: 11338404
    Abstract: A machine tool and a control apparatus thereof include an amplitude control unit to control the amplitude of reciprocal vibration by a vibration unit. The amplitude control unit is configured to reduce the amplitude of the reciprocal vibration by the vibration unit as a cutting tool is fed in a feeding direction when the cutting tool reaches a predetermined cutting tool work stopping position on a workpiece in the feeding direction (Z-axis direction) to prevent the cutting tool from cutting the workpiece beyond the cutting tool work stopping position.
    Type: Grant
    Filed: September 14, 2015
    Date of Patent: May 24, 2022
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD
    Inventors: Kazuhiko Sannomiya, Takaichi Nakaya
  • Patent number: 11338386
    Abstract: Disclosed is a friction welding method including: a heating step wherein, in relation to joining surfaces (S1, S2) defined by opposite end surfaces of a pair of materials (W1, W2), the pair of materials (W1, W2) are moved from a state in which their axes are unaligned with each other, in a direction for aligning the respective axes with each other, to a prescribed position where the joining surfaces (S1, S2) are brought into contact with each other and friction heated; and a pressure contacting step wherein the pair of materials are brought into pressure contact with each other. The method is characterized in that the heating step and the pressure contacting step are carried out while rotating each of the materials (W1, W2) at the same rotation speed in the same direction, as seen from one side in the axial direction.
    Type: Grant
    Filed: October 31, 2018
    Date of Patent: May 24, 2022
    Assignees: CITIZEN WATCH CO., LTD., CITIZEN MACHINERY CO., LTD.
    Inventor: Takaichi Nakaya