Patents by Inventor Seiji Tada

Seiji Tada has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8986145
    Abstract: There are provided a power transmission chain which can reduce a noise level further by eliminating unfavorable combinations from a random arrangement of combinations of pitch lengths and pin shapes and a power transmission system using the same power transmission chain. With respect to pitch length, links include two types of a link L1 which has a small pitch length and a link L2 which has a large pitch length. With respect to pin shape, pins include two types a pin P1 of which a curvature of a rolling contact surface is large and a pin P2 of which the curvature of the rolling contact surface is small. The links are arranged so that a possibility is avoided that a combination of (L2, P2) and a combination of (L2, P1) come immediately after a combination of (L1, P2) in a chain traveling direction, and that a possibility is adopted that a combination of (L1, P2) or a combination of (L1, P1) comes immediately after the combination of (L1, P2).
    Type: Grant
    Filed: September 24, 2008
    Date of Patent: March 24, 2015
    Assignee: JTEKT Corporation
    Inventors: Shigeo Kamamoto, Seiji Tada
  • Patent number: 8979687
    Abstract: A torque transmission chain and torque transmission device of which the strength of links is increased by devising lock points that regulate the maximum relative rotation angle between the links are provided. Lock points that contact with pins and interpieces to regulate the maximum relative rotation angles are provided at four portions, that is, a front surface of a link front pillar portion, a rear surface of a link rear pillar portion and a front surface and rear surface of a link intermediate pillar portion. Each of allowable maximum relative rotation angles regulated by the lock points of a link outline portion is set so as to be smaller than each of allowable maximum relative rotation angles regulated by the lock points of the link intermediate pillar portion.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: March 17, 2015
    Assignee: JTEKT Corporation
    Inventors: Seiji Tada, Shigeo Kamamoto
  • Patent number: 8894524
    Abstract: A power transmission chain includes a plurality of link units which are aligned in a chain advancing direction, and each link unit includes a plurality of link plates which are aligned in a chain width direction W. The plurality of link plates include link plates which are punched out of a material by pressing to first and second specifications. A punching direction of the link plates to the first specification and a punching direction of the link plates to the second specification are made opposite to each other.
    Type: Grant
    Filed: December 14, 2007
    Date of Patent: November 25, 2014
    Assignees: JTEKT Corporation, Todo Kogyo Co., Ltd
    Inventors: Kozue Matsumoto, Seiji Tada, Shigeo Kamamoto, Yasutaka Hojo
  • Patent number: 8708851
    Abstract: With a view to suppressing fretting in a power transmission chain, when a chain straight-line area is seen from a chain widthwise direction W, a flat portion 18 of a first pin 3 of the chain extends in an inclination direction D. A point of intersection P0 is formed by an imaginary line L1 which passes through a center position of an overall height h of the first pin 3 along the inclination direction D intersecting the flat portion. A point of intersection P2 is formed by an imaginary line L2 which passes through a contact portion A0 and which extends in a chain advancing direction X intersecting the flat portion 18 between the point of intersection P0 and one end P1 of the flat portion. When assuming that a distance between the point of intersection P0 and the point of intersection P2 is referred to as h1 and a distance between the point of intersection P2 and the one end P1 of the flat portion 18 is referred to as h2, 0.1·h1?h2.
    Type: Grant
    Filed: February 25, 2009
    Date of Patent: April 29, 2014
    Assignee: JTEKT Corporation
    Inventors: Seiji Tada, Shigeo Kamamoto
  • Patent number: 8636611
    Abstract: A power transmission chain including a plurality of links each having front and rear insertion through holes through which pins are inserted, and a plurality of first pins and a plurality of second pins which are arranged in a line for connecting together the links which are arranged in a chain width direction. The links are made up of links of small pitch length and links of large pitch length. The links of large pitch length corresponding to the first pin or the second pin that is clamped by the pulley are arranged such that the links of large pitch length are always included in one to one-half in total when a winding contact diameter of the pulley is a minimum operation radius.
    Type: Grant
    Filed: October 17, 2008
    Date of Patent: January 28, 2014
    Assignee: JTEKT Corporation
    Inventors: Shigeo Kamamoto, Seiji Tada
  • Patent number: 8617017
    Abstract: The invention provides a power transmission chain in which abnormal noise can be reduced. In a link, a front through hole 7 and a rear through hole 8 aligned in a chain traveling direction X are provided. A pillar portion 9 is provided between the front through hole 7 and the rear through hole 8. Projecting portions 26, 29 are provided at a central portion in a height direction V of the pillar portion 9, and concave curve portions 27, 28, 30, 31 are provided at both end portions. A pair of flat portions (33,34 and 38,39) are provided on each projection portion 26,29 for restricting an overshoot of the chain. A not-shown pin that is loosely fitted to each of the front through hole 7 and the rear through hole 8 is brought into abutment with corresponding flat portions 27,28,30,31 to restrict an overshoot of the chain 1.
    Type: Grant
    Filed: November 7, 2008
    Date of Patent: December 31, 2013
    Assignee: JTEKT Corporation
    Inventors: Seiji Tada, Shigeo Kamamoto
  • Publication number: 20120149512
    Abstract: A torque transmission chain and torque transmission device of which the strength of links is increased by devising lock points that regulate the maximum relative rotation angle between the links are provided. Lock points that contact with pins and interpieces to regulate the maximum relative rotation angles are provided at four portions, that is, a front surface of a link front pillar portion, a rear surface of a link rear pillar portion and a front surface and rear surface of a link intermediate pillar portion. Each of allowable maximum relative rotation angles regulated by the lock points of a link outline portion is set so as to be smaller than each of allowable maximum relative rotation angles regulated by the lock points of the link intermediate pillar portion.
    Type: Application
    Filed: August 31, 2010
    Publication date: June 14, 2012
    Applicant: JTEKT CORPORATION
    Inventors: Seiji Tada, Shigeo Kamamoto
  • Patent number: 8100794
    Abstract: When disposing pins of different shapes at random, pins of small involute base circle radius are made not to be arranged contiguously, pins of relatively small length are made not to be arranged contiguously, and pins of relatively outward offset are made not to be arranged contiguously.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: January 24, 2012
    Assignee: JTEKT Corporation
    Inventors: Shigeo Kamamoto, Seiji Tada
  • Patent number: 8038559
    Abstract: The end faces of a first pin contain bulging curved faces having an egg-like shape, when viewed along a chain width direction. Each bulging curved face includes a first end portion, a second end portion and a maximum width portion with respect to a chain advancing direction. With respect to perpendicular directions, the distance between the center of the maximum width portion and the first end portion is relatively large, whereas the distance between the center of the maximum width portion and the second end portion is relatively short. It is possible to enlarge the surface area of the bulging curved face.
    Type: Grant
    Filed: August 3, 2007
    Date of Patent: October 18, 2011
    Assignee: JTEKT Corporation
    Inventors: Seiji Tada, Shigeo Kamamoto
  • Patent number: 7976224
    Abstract: The invention provides an eccentric thrust bearing assembly capable of bearing axial loads in opposite directions. A first aspect of the invention relates to a thrust bearing assembly a1 wherein a first radially outside member and a second radially inside member oppose each other at first positions a21 separately located and clamp therebetween a rolling element a8 disposed at each of the first positions a21, whereas a second radially outside member and a first radially inside member oppose each other at second positions a22 of a different phase from that of the first positions a21 and clamp therebetween a rolling element a8 disposed at each of the second positions a22. In this bearing assembly a1, respective certain portions of the rolling elements are present on the same plane.
    Type: Grant
    Filed: May 15, 2009
    Date of Patent: July 12, 2011
    Assignee: JTEKT Corporation
    Inventor: Seiji Tada
  • Publication number: 20110119592
    Abstract: Each of a plurality of displays transmits an operation state of the display to a management device. The management device stores the operation states corresponding to the plurality of displays in a memory. Based on the operation states corresponding to the plurality of displays and stored in the memory, the management device transmits a command for causing the display to perform the same operation as the other displays. Each of the plurality of displays changes the operation state of the display based on the command provided from the management device.
    Type: Application
    Filed: November 16, 2010
    Publication date: May 19, 2011
    Applicant: Sharp Kabushiki Kaisha
    Inventor: Seiji Tada
  • Patent number: 7892127
    Abstract: A chain (1) includes plural links (2) and plural pairs of first and second pins (3 and 4) to couple the links each other. The first pin (3) comes into rolling and sliding contact with the second pin (4) at the contact portion (D). The first pin (3) includes a pair of end faces (17) opposing each other in the chain width direction (W), and a contact region (24) that comes into contact with the corresponding sheave surfaces of the pulley is formed in each end face (17). The contact region (24) includes the center point of contact (M). The first pin (3) includes a first type pin (3a) and a second type pin (3b). When the linear region of the chain (1) is viewed in the chain width direction (W), the relative position of the contact portion (D) and the center point of contact (M) is different between the first type pin (3a) and the second type pin (3b).
    Type: Grant
    Filed: February 3, 2006
    Date of Patent: February 22, 2011
    Assignee: JTEKT Corporation
    Inventors: Seiji Tada, Shigeo Kamamoto
  • Patent number: 7882689
    Abstract: In the state where plural sheets of link plates which are single parts are laminated, tension for widening a distance between through-holes is loaded by a pair of pins which are inserted through the through-holes of the link plates so as to load pretension serving as a predetermined compressive residual stress on the link plates. Subsequently, the pair of pins are extracted from the link plates. Consequently, connection members are inserted through the corresponding through-holes of the plurality of link plates so as to assemble a chain with an endless shape.
    Type: Grant
    Filed: January 25, 2008
    Date of Patent: February 8, 2011
    Assignee: JTEKT Corporation
    Inventors: Seiji Tada, Kozue Matsumoto, Kazuo Rokkaku
  • Patent number: 7874952
    Abstract: A power transmission chain includes a plurality of links aligned in a chain travel direction and a coupling member that includes a first power transmission member and a second power transmission member. The first power transmission member includes an opposing portion that opposes the corresponding second power transmission member and contacts the corresponding second power transmission member on a contact portion that undergoes displacement in association with a change of a bending angle between corresponding links in a contact state including at least one of rolling contact and sliding contact. The opposing portion includes an arc-shaped portion having a predetermined radius of curvature and a rate-of-change increasing portion. The arc-shaped portion includes a portion that forms the contact portion when the bending angle is equal to or greater than zero and equal to or smaller than a predetermined boundary angle.
    Type: Grant
    Filed: September 12, 2007
    Date of Patent: January 25, 2011
    Assignee: JTEKT Corporation
    Inventors: Seiji Tada, Shigeo Kamamoto
  • Publication number: 20110003658
    Abstract: With a view to suppressing fretting in a power transmission chain, when a chain straight-line area is seen from a chain widthwise direction W, a flat portion 18 of a first pin 3 of the chain extends in an inclination direction D. A point of intersection P0 is formed by an imaginary line L1 which passes through a center position of an overall height h of the first pin 3 along the inclination direction D intersecting the flat portion. A point of intersection P2 is formed by an imaginary line L2 which passes through a contact portion A0 and which extends in a chain advancing direction X intersecting the flat portion 18 between the point of intersection P0 and one end P1 of the flat portion. When assuming that a distance between the point of intersection P0 and the point of intersection P2 is referred to as h1 and a distance between the point of intersection P2 and the one end P1 of the flat portion 18 is referred to as h2, 0.1·h1?h2.
    Type: Application
    Filed: February 25, 2009
    Publication date: January 6, 2011
    Inventors: Seiji Tada, Shigeo Kamamoto
  • Publication number: 20100279805
    Abstract: There are provided a power transmission chain which can improve not only noise level but also durability by eliminating unfavorable combinations from a random arrangement of combinations of pitch lengths and pin shapes by paying attention to maximum bending angle and bending angle minimum value and a power transmission system using the same power transmission chain. With respect to pitch length, links include two types of a link L1 which has a small pitch length and a link L2 which has a large pitch length. With respect to pin shape, pins include two types; a pin P1 of which a curvature of a rolling contact surface is large and a pin P2 of which the curvature of the rolling contact surface is small.
    Type: Application
    Filed: September 25, 2008
    Publication date: November 4, 2010
    Inventors: Shigeo Kamamoto, Seiji Tada
  • Publication number: 20100248881
    Abstract: The invention provides a power transmission chain in which abnormal noise can be reduced. In a link, a front through hole 7 and a rear through hole 8 aligned in a chain traveling direction X are provided. A pillar portion 9 is provided between the front through hole 7 and the rear through hole 8. Projecting portions 26, 29 are provided at a central portion in a height direction V of the pillar portion 9, and concave curve portions 27, 28, 30, 31 are provided at both end portions. A pair of flat portions (33,34 and 38,39) are provided on each projection portion 26,29 for restricting an overshoot of the chain. A not-shown pin that is loosely fitted to each of the front through hole 7 and the rear through hole 8 is brought into abutment with corresponding flat portions 27,28,30,31 to restrict an overshoot of the chain 1.
    Type: Application
    Filed: November 7, 2008
    Publication date: September 30, 2010
    Inventors: Seiji Tada, Shigeo Kamamoto
  • Publication number: 20100203988
    Abstract: There are provided a power transmission chain which can reduce a noise level further by eliminating unfavorable combinations from a random arrangement of combinations of pitch lengths and pin shapes and a power transmission system using the same power transmission chain. With respect to pitch length, links include two types of a link L1 which has a small pitch length and a link L2 which has a large pitch length. With respect to pin shape, pins include two types a pin P1 of which a curvature of a rolling contact surface is large and a pin P2 of which the curvature of the rolling contact surface is small. The links are arranged so that a possibility is avoided that a combination of (L2, P2) and a combination of (L2, P1) come immediately after a combination of (L1, P2) in a chain traveling direction, and that a possibility is adopted that a combination of (L1, P2) or a combination of (L1, P1) comes immediately after the combination of (L1, P2).
    Type: Application
    Filed: September 24, 2008
    Publication date: August 12, 2010
    Applicant: JTEKT
    Inventors: Shigeo Kamamoto, Seiji Tada
  • Publication number: 20100099531
    Abstract: A power transmission chain includes a plurality of link units which are aligned in a chain advancing direction, and each link unit includes a plurality of link plates which are aligned in a chain width direction W. The plurality of link plates include link plates which are punched out of a material by pressing to first and second specifications. A punching direction of the link plates to the first specification and a punching direction of the link plates to the second specification are made opposite to each other.
    Type: Application
    Filed: December 14, 2007
    Publication date: April 22, 2010
    Inventors: Kozue Matsumoto, Seiji Tada, Shigeo Kamamoto, Yasutaka Hojo
  • Publication number: 20100069189
    Abstract: [Problems to be Solved] To provide a power transmission chain which not only can prevent the occurrence of an edge contact phenomenon in which the edge portion of a pin end face is contacted with a pulley, but also can enhance the power transmission efficiency. [Means for Solution] According the power transmission chain, in the end face 17 of a first pin 3 for connecting links to each other, there is provided a contact area 21. The contact area 21 is contacted with the pulley to transmit power. When viewed from the width direction of the chain, the contact area 21 has an egg-like shape which is relatively long in a longitudinal direction J and relatively short in a transverse direction K. The contact area 21 intersects with a first plane H1 to form a first intersection line L1. The contact area 21 intersects with a second plane H2 to form a second intersection line L2. The first intersection line L1 has a plurality of radiuses of curvature R1, R2.
    Type: Application
    Filed: October 18, 2007
    Publication date: March 18, 2010
    Inventor: Seiji Tada