Patents by Inventor Koji Saga

Koji Saga 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: 11905948
    Abstract: In a variable displacement type oil pump, a swing member accommodates a pump forming member, and swings to vary a quantity of change of a volumetric capacity of each pump chamber. A biasing member biases the swing member in a direction to increase the quantity of change of the volumetric capacity of each pump chamber. A first control oil chamber applies a first torque to the swing member in a direction to reduce the quantity of change of the volumetric capacity of each pump chamber. A second control oil chamber applies a second torque to the swing member in a direction to increase the quantity of change of the volumetric capacity of each pump chamber, wherein the second torque is larger than the first torque. A switching mechanism switches between supply and drain of working oil with respect to the second control oil chamber.
    Type: Grant
    Filed: March 31, 2016
    Date of Patent: February 20, 2024
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Koji Saga, Yasushi Watanabe, Hideaki Ohnishi, Atsushi Naganuma
  • Patent number: 11603779
    Abstract: An oil pump includes a pump component, a valve container, a valve mechanism, and a circumvention passage. The valve container includes a through hole establishing communication between an inside and an outside of the valve container. The valve mechanism includes: a valve body contained in the valve container; a valve element contained movably in the valve body; a back pressure chamber disposed to face a first valve end of the valve element; a drive mechanism disposed to face a second valve end of the valve element and structured to generate a drive force to move the valve element; and an aperture positioned higher in a vertical direction than the through hole and formed in the valve body so as to establish communication between the back pressure chamber and the inside of the valve container. The circumvention passage establishes communication between the through hole and the aperture.
    Type: Grant
    Filed: September 10, 2019
    Date of Patent: March 14, 2023
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Koji Saga, Tadao Nakamura
  • Patent number: 11415128
    Abstract: A variable displacement pump device includes a pump, a mover, a biasing member, first and second control chambers, and a controller. The first and second control chambers are provided between an inner periphery of a containing chamber of a housing and an outer periphery of the mover. Hydraulic oil is introduced from a discharge port into the first control chamber. The pump is configured to permit oil to be introduced from the discharge port into the second control chamber via a supply/discharge passage or to be discharged from inside the second control chamber. The second control chamber is located adjacent to any of the pump chambers in a discharge region or the discharge port via the mover. The controller is configured to switch states in which the second control chamber is opened and closed to the supply/discharge passage.
    Type: Grant
    Filed: June 8, 2018
    Date of Patent: August 16, 2022
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Koji Saga, Hideaki Ohnishi
  • Patent number: 11215178
    Abstract: Provided is a variable capacity pump where ease of control can be improved. A variable capacity pump includes a control chamber and a control mechanism. The control chamber is disposed between a pump accommodating chamber and a movable member, and the volume of the control chamber is variable with the movement of the movable member. Working oil discharged from a discharge portion is introduced into the control chamber. The control mechanism includes a spool, a biasing member, and a solenoid. The spool is provided in a passage, and is configured to control introduction of working oil into the control chamber by moving in a cylindrical portion. The spool is biased to one side in an axial direction by a pressure of working oil introduced into the cylindrical portion from the discharge portion. The biasing member biases the spool to an opposite side in the axial direction.
    Type: Grant
    Filed: August 4, 2017
    Date of Patent: January 4, 2022
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Yasushi Watanabe, Atsushi Naganuma, Koji Saga, Hideaki Ohnishi
  • Publication number: 20210381405
    Abstract: An oil pump includes a pump component, a valve container, a valve mechanism, and a circumvention passage. The valve container includes a through hole establishing communication between an inside and an outside of the valve container. The valve mechanism includes: a valve body contained in the valve container; a valve element contained movably in the valve body; a back pressure chamber disposed to face a first valve end of the valve element; a drive mechanism disposed to face a second valve end of the valve element and structured to generate a drive force to move the valve element; and an aperture positioned higher in a vertical direction than the through hole and formed in the valve body so as to establish communication between the back pressure chamber and the inside of the valve container. The circumvention passage establishes communication between the through hole and the aperture.
    Type: Application
    Filed: September 10, 2019
    Publication date: December 9, 2021
    Inventors: Koji SAGA, Tadao NAKAMURA
  • Patent number: 11168684
    Abstract: Variable displacement pump has first control hydraulic chamber 21 giving force to cam ring 5 in direction that decreases volume variation of each pump chamber 13 by internal pressure, second control hydraulic chamber 22 giving force to cam ring in direction that increases volume variation of each pump chamber by internal pressure, first seal surface 44 formed on both end surfaces of cam ring, which are in sliding-contact with both opposing inside surfaces of pump body 1 and cover member 2, and sealing gap between each pump chamber and first control hydraulic chamber, and second seal surface 45 sealing gap between each pump chamber and second control hydraulic chamber at outlet section side. Radial direction width W2 of second seal surface is greater than that W1 of first seal surface. Increase in weight of the pump can be suppressed while suppressing increase in pump control pressure against intention of control.
    Type: Grant
    Filed: February 6, 2017
    Date of Patent: November 9, 2021
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Koji Saga, Hideaki Ohnishi, Yasushi Watanabe
  • Publication number: 20200141403
    Abstract: The present invention provides a variable displacement pump capable of improving controllability. A variable displacement pump includes a pump forming member, a movable member, a biasing member, a first control chamber, a second control chamber, and a control mechanism. The first control chamber is provided between an inner periphery of a containing chamber of a housing and an outer periphery of the movable member. Hydraulic oil is introduced from a discharge port into the first control chamber. The first control chamber has a volume that increases when the movable member moves in a direction counteracting a biasing force of the biasing member. The second control chamber is provided between the inner periphery of the containing chamber and the outer periphery of the movable member. The hydraulic oil is able to be introduced from the discharge port into the second control chamber via a supply/discharge passage or is able to be discharged from inside the second control chamber.
    Type: Application
    Filed: June 8, 2018
    Publication date: May 7, 2020
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Koji SAGA, Hideaki OHNISHI
  • Publication number: 20200032793
    Abstract: Variable displacement pump has first control hydraulic chamber 21 giving force to cam ring 5 in direction that decreases volume variation of each pump chamber 13 by internal pressure, second control hydraulic chamber 22 giving force to cam ring in direction that increases volume variation of each pump chamber by internal pressure, first seal surface 44 formed on both end surfaces of cam ring, which are in sliding-contact with both opposing inside surfaces of pump body 1 and cover member 2, and sealing gap between each pump chamber and first control hydraulic chamber, and second seal surface 45 sealing gap between each pump chamber and second control hydraulic chamber at outlet section side. Radial direction width W2 of second seal surface is greater than that W1 of first seal surface. Increase in weight of the pump can be suppressed while suppressing increase in pump control pressure against intention of control.
    Type: Application
    Filed: February 6, 2017
    Publication date: January 30, 2020
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Koji SAGA, Hideaki OHNISHI, Yasushi WATANABE
  • Publication number: 20190226479
    Abstract: Provided is a variable capacity pump where ease of control can be improved. A variable capacity pump includes a control chamber and a control mechanism. The control chamber is disposed between a pump accommodating chamber and a movable member, and the volume of the control chamber is variable with the movement of the movable member. Working oil discharged from a discharge portion is introduced into the control chamber. The control mechanism includes a spool, a biasing member, and a solenoid. The spool is provided in a passage, and is configured to control introduction of working oil into the control chamber by moving in a cylindrical portion. The spool is biased to one side in an axial direction by a pressure of working oil introduced into the cylindrical portion from the discharge portion. The biasing member biases the spool to an opposite side in the axial direction.
    Type: Application
    Filed: August 4, 2017
    Publication date: July 25, 2019
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Yasushi WATANABE, Atsushi NAGANUMA, Koji SAGA, Hideaki OHNISHI
  • Publication number: 20190219053
    Abstract: Provided is a variable capacity pump where ease of control can be improved. A variable capacity pump includes a control chamber and a control valve. The control chamber is disposed between a pump accommodating chamber and a movable member, and the volume of the control chamber is variable with the movement of the movable member. Working oil discharged from a discharge portion is introduced into the control chamber. The control valve is provided in a passage and, with the movement of a valve element, the control valve varies the cross-sectional area of a flow passage, through which working oil in the control chamber is drained to a low pressure portion, while making the discharge portion and the control chamber communicate with each other.
    Type: Application
    Filed: August 4, 2017
    Publication date: July 18, 2019
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Atsushi NAGANUMA, Hideaki OHNISHI, Yasushi WATANABE, Koji SAGA
  • Patent number: 10161398
    Abstract: In a variable displacement oil pump, a drain chamber 36 partitioned with respect to first and second control oil chambers 31, 32 and which serves to generate a biasing force in a concentric direction based on a pump drain pressure directly introduced from a drain port 22a is interposed between first control oil chamber 31 which serves to generate a biasing force in the concentric direction in which a volume variation quantity of a plurality of pump chambers PR for a cam ring 15 based on a control pressure as a main gallery pressure introduced from an internal combustion engine and second control oil chamber 32 which serves to generate the biasing force in an eccentric direction in which the volume variation quantity of the plurality of pump chambers PR is increased for cam ring 15 based on the control pressure.
    Type: Grant
    Filed: October 15, 2015
    Date of Patent: December 25, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventor: Koji Saga
  • Patent number: 10060433
    Abstract: A variable displacement pump includes: a control mechanism arranged to be actuated based on a hydraulic pressure introduced into the introduction passage before the eccentric amount is minimized, and arranged to introduce the hydraulic pressure through a throttling to the second control hydraulic chamber when the hydraulic pressure introduced from the introduction passage is equal to or smaller than a predetermined pressure, and to discharge the hydraulic fluid within the second control hydraulic chamber in accordance with the hydraulic pressure when the hydraulic pressure introduced from the introduction passage becomes greater than the predetermined pressure; and a switching mechanism arranged to switch between a state in which the hydraulic fluid introduced into the introduction passage is introduced to the control mechanism, and a state in which the hydraulic fluid introduced into the introduction passage is discharged from the control mechanism.
    Type: Grant
    Filed: October 11, 2016
    Date of Patent: August 28, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventor: Koji Saga
  • Publication number: 20180187676
    Abstract: In a variable displacement type oil pump, a swing member accommodates a pump forming member, and swings to vary a quantity of change of a volumetric capacity of each pump chamber. A biasing member biases the swing member in a direction to increase the quantity of change of the volumetric capacity of each pump chamber. A first control oil chamber applies a first torque to the swing member in a direction to reduce the quantity of change of the volumetric capacity of each pump chamber. A second control oil chamber applies a second torque to the swing member in a direction to increase the quantity of change of the volumetric capacity of each pump chamber, wherein the second torque is larger than the first torque. A switching mechanism switches between supply and drain of working oil with respect to the second control oil chamber.
    Type: Application
    Filed: March 31, 2016
    Publication date: July 5, 2018
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Koji SAGA, Yasushi WATANABE, Hideaki OHNISHI, Atsushi NAGANUMA
  • Patent number: 9903367
    Abstract: A variable displacement oil pump for an internal combustion engine includes a pump element to vary inside volumes of pumping chambers to suck and discharge an oil, a varying mechanism to vary a pumping volume variation quantity of the pumping chambers, with movement of a movable member such as a cam ring, an urging mechanism to urge the movable member in a direction to increase the pumping volume variation quantity, first and second control oil chambers to urge the movable member to vary the pumping volume variation quantity, and a control mechanism, such as a pilot valve, to control the supply/drainage of the oil to or from the second control oil chamber. An operation oil pressure of the movable member is set higher than an operation oil pressure of the control mechanism in a higher pressure region.
    Type: Grant
    Filed: October 27, 2015
    Date of Patent: February 27, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Yasushi Watanabe, Hideaki Ohnishi, Koji Saga, Atsushi Naganuma
  • Publication number: 20170030351
    Abstract: A variable displacement pump includes: a control mechanism arranged to be actuated based on a hydraulic pressure introduced into the introduction passage before the eccentric amount is minimized, and arranged to introduce the hydraulic pressure through a throttling to the second control hydraulic chamber when the hydraulic pressure introduced from the introduction passage is equal to or smaller than a predetermined pressure, and to discharge the hydraulic fluid within the second control hydraulic chamber in accordance with the hydraulic pressure when the hydraulic pressure introduced from the introduction passage becomes greater than the predetermined pressure; and a switching mechanism arranged to switch between a state in which the hydraulic fluid introduced into the introduction passage is introduced to the control mechanism, and a state in which the hydraulic fluid introduced into the introduction passage is discharged from the control mechanism.
    Type: Application
    Filed: October 11, 2016
    Publication date: February 2, 2017
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventor: Koji SAGA
  • Patent number: 9556867
    Abstract: A vane pump includes a rotor including a first annular groove and a second annular groove. The rotor further includes a cylindrical portion projecting axially from a radial inner side of the first annular groove and fitting over a drive shaft, and a slide contact portion formed on a radial inner side of the second annular groove. The cylindrical portion is slidably received in a bearing hole formed in a first side wall of a housing, whereas the slide contact portion abuts slidably on an inside wall surface of a second side wall of the housing. There is further formed, in the first annular groove, a recessed portion making a pressure receiving area of one of the first and second annular grooves greater than a pressure receiving area of the other of the first and second annular grooves.
    Type: Grant
    Filed: October 17, 2014
    Date of Patent: January 31, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Koji Saga, Hideaki Ohnishi, Yasushi Watanabe
  • Patent number: 9534596
    Abstract: A variable displacement pump including a control mechanism shiftable between first and second states, when the control mechanism is in the first state, the spool is in an initial position in which fluid communication between an introduction port and the remaining ports is restrained, fluid communication between a first control port and a drain port is allowed, and fluid communication between a second control port and the drain port is restrained, and when the control mechanism is shifted to the second state in accordance with increase in fluid pressure discharged, the spool is in an operating position in which the fluid communication between the introduction port and the first control port is allowed, the fluid communication between the first control port and the drain port is restrained, and the fluid communication between the second control port and the drain port is allowed.
    Type: Grant
    Filed: November 21, 2013
    Date of Patent: January 3, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Yasushi Watanabe, Koji Saga, Hideaki Ohnishi
  • Patent number: 9494153
    Abstract: A variable displacement oil pump includes: a switching mechanism arranged to switch a state in which the hydraulic fluid is introduced to the second control hydraulic chamber through a connection passage, and a state in which the hydraulic fluid is discharged from the second control hydraulic chamber through the connection passage; and a control mechanism arranged to be actuated before the eccentric amount of the cam ring becomes minimum, and arranged to vary an opening area of the connection passage as the discharge pressure is increased, and to vary an opening area of a discharge passage arranged to discharge the hydraulic fluid within the second control hydraulic chamber, in a direction opposite to a direction of a variation of the opening area of the introduction passage.
    Type: Grant
    Filed: November 6, 2013
    Date of Patent: November 15, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Yasushi Watanabe, Hideaki Ohnishi, Koji Saga
  • Patent number: 9494152
    Abstract: A variable displacement pump includes: a control mechanism arranged to be actuated based on a hydraulic pressure introduced into the introduction passage before the eccentric amount is minimized, and arranged to introduce the hydraulic pressure through a throttling to the second control hydraulic chamber when the hydraulic pressure introduced from the introduction passage is equal to or smaller than a predetermined pressure, and to discharge the hydraulic fluid within the second control hydraulic chamber in accordance with the hydraulic pressure when the hydraulic pressure introduced from the introduction passage becomes greater than the predetermined pressure; and a switching mechanism arranged to switch between a state in which the hydraulic fluid introduced into the introduction passage is introduced to the control mechanism, and a state in which the hydraulic fluid introduced into the introduction passage is discharged from the control mechanism.
    Type: Grant
    Filed: November 6, 2013
    Date of Patent: November 15, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventor: Koji Saga
  • Publication number: 20160177950
    Abstract: A variable displacement oil pump for an internal combustion engine includes a pump element to vary inside volumes of pumping chambers to suck and discharge an oil, a varying mechanism to vary a pumping volume variation quantity of the pumping chambers, with movement of a movable member such as a cam ring, an urging mechanism to urge the movable member in a direction to increase the pumping volume variation quantity, first and second control oil chambers to urge the movable member to vary the pumping volume to variation quantity, and a control mechanism, such as a pilot valve, to control the supply/drainage of the oil to or from the second control oil chamber. An operation oil pressure of the movable member is set higher than an operation oil pressure of the control mechanism in a higher pressure region.
    Type: Application
    Filed: October 27, 2015
    Publication date: June 23, 2016
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Yasushi WATANABE, Hideaki OHNISHI, Koji SAGA, Atsushi NAGANUMA