Patents by Inventor Nobuo Tojo

Nobuo Tojo 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: 12247665
    Abstract: A seal structure includes an annular female adapter, at least one annular packing, and an annular male adapter. The male adapter and the female adapter sandwich the at least one packing. The at least one packing includes a packing convex portion adjacent to the female adapter and a packing concave portion adjacent to the male adapter. The male adapter includes an adapter convex portion that contacts the packing concave portion. The female adapter includes an adapter concave portion that contacts the packing convex portion. In a state sandwiched between the male adapter and the female adapter, the at least one packing includes an inner diameter that is smaller than a diameter of the reciprocating member. The female adapter includes an inner diameter that is smaller than the diameter of the reciprocating member.
    Type: Grant
    Filed: June 29, 2023
    Date of Patent: March 11, 2025
    Inventor: Nobuo Tojo
  • Publication number: 20240369148
    Abstract: A pressure regulating valve includes a body having a pressure regulating chamber into which a working liquid flows and an attachment hole fluidly coupling with the pressure regulating chamber, a valve seat assembly fitted in the attachment hole, wherein the valve seat assembly includes a surplus liquid discharge path fluidly coupled with the pressure regulating chamber, a piston configured to open and close an opening of the surplus liquid discharge path in the pressure regulating chamber, a valve seat seal forming a seal between the valve seat assembly and the body in the attachment hole in a liquid-tight manner and a return flow path fluidly coupling an inside of the attachment hole to the surplus liquid discharge path. Wherein the valve seat seal is located between the return flow path and the pressure regulating chamber.
    Type: Application
    Filed: April 11, 2024
    Publication date: November 7, 2024
    Inventor: Nobuo TOJO
  • Publication number: 20240141889
    Abstract: A seal structure configured to be located between a space forming member forming a columnar inner space and a columnar reciprocating member move in the inner space. The seal structure includes an annular seal member that is configured to be located in the inner space, an annular pressing portion which is located adjacent to the seal member and is configured to press the seal member in an axial direction, a compressive coil spring which is located adjacent to the pressing portion, and a cylindrical collar portion. The cylindrical collar portion is at least partially surrounded by the compressive coil spring to avoid interference between the compressive coil spring and the reciprocating member.
    Type: Application
    Filed: September 27, 2023
    Publication date: May 2, 2024
    Inventors: Nobuo TOJO, Yoshitaka YAMANAKA
  • Publication number: 20240003422
    Abstract: A seal structure includes an annular female adapter, at least one annular packing, and an annular male adapter. The male adapter and the female adapter sandwich the at least one packing. The at least one packing includes a packing convex portion adjacent to the female adapter and a packing concave portion adjacent to the male adapter. The male adapter includes an adapter convex portion that contacts the packing concave portion. The female adapter includes an adapter concave portion that contacts the packing convex portion. In a state sandwiched between the male adapter and the female adapter, the at least one packing includes an inner diameter that is smaller than a diameter of the reciprocating member. The female adapter includes an inner diameter that is smaller than the diameter of the reciprocating member.
    Type: Application
    Filed: June 29, 2023
    Publication date: January 4, 2024
    Inventor: Nobuo TOJO
  • Patent number: 10808693
    Abstract: A reciprocating pump includes a first manifold which includes a pump chamber, a second manifold which is connected to the first manifold, and a seal which is disposed inside the second manifold and comes into slidable contact with a plunger. A communication pipe which extends across an inside of the first manifold and an inside of the second manifold comes into contact with the seal. Additionally, the reciprocating pump includes a collar which is disposed inside the first manifold and comes into contact with the communication pipe through which the plunger is inserted. The collar, the communication pipe, and the seal are sandwiched between the inside of the first manifold and the inside of the second manifold.
    Type: Grant
    Filed: December 11, 2017
    Date of Patent: October 20, 2020
    Inventor: Nobuo Tojo
  • Publication number: 20180163719
    Abstract: A reciprocating pump includes a first manifold which includes a pump chamber, a second manifold which is connected to the first manifold, and seal means which is disposed inside the second manifold and comes into slidable contact with a plunger. A communication pipe which extends across an inside of the first manifold and an inside of the second manifold comes into contact with the seal means. Additionally, the reciprocating pump includes a collar which is disposed inside the first manifold and comes into contact with the communication pipe through which the plunger is inserted. The collar, the communication pipe, and the seal means are sandwiched between the inside of the first manifold and the inside of the second manifold.
    Type: Application
    Filed: December 11, 2017
    Publication date: June 14, 2018
    Applicant: MARUYAMA MFG. CO., INC.
    Inventor: Nobuo Tojo
  • Publication number: 20090257897
    Abstract: The present invention provides a pump having a compact and lightweight design, which enables an improvement in pump efficiency and a reduction in noise. The pump comprises a manifold having a pump chamber, a suction port for sucking fluid from the outside to the inside of the manifold, a discharge port for discharging fluid from the inside to the outside of the manifold, a suction valve which is provided between a suction port and a pump chamber, and opens and closes a flow path of fluid to the pump chamber, and a discharge valve which is provided between the pump chamber and the discharge port, and opens and closes a flow path of fluid from the pump chamber. Furthermore, the suction port, the suction valve, the discharge valve and the discharge port are arranged coaxially, thereby the fluid does not meet unnecessary resistance, the fluid is made to flow smoothly, pump efficiency can be improved, noise can be reduced, and the structure of the manifold can be simplified and made compact and lightweight.
    Type: Application
    Filed: April 6, 2009
    Publication date: October 15, 2009
    Applicant: Maruyama Mfg. Co., Inc.
    Inventor: Nobuo Tojo
  • Publication number: 20070237651
    Abstract: An objective is to provide a reciprocating pump apparatus which can change a position where an adaptor to be fixed to a support is attached, while having a simple form. In a reciprocating pump apparatus 10 having a crankshaft 14 directly connected to an output shaft of a driving source, positions of bolts 22a to 22d for fixing a bearing case 20 for closing an open end part of a crankcase 16 to the crankcase are determined such that an adaptor 40 for fixing the reciprocating pump apparatus to a support 58 is fastened to the crankcase together with the bearing case in a positionally changeable fashion. Since the position of the adaptor is changeable, the degree of freedom in the layout of apparatus improves in this structure. Also, since bolts for fixing a manifold to the crankcase are utilized for attaching the adaptor, a simple form is attained.
    Type: Application
    Filed: March 28, 2007
    Publication date: October 11, 2007
    Applicant: Maruyama Mfg. Co., Inc.
    Inventor: Nobuo Tojo
  • Patent number: 6053091
    Abstract: A plunger pump comprising a plunger pump section (34) including a pumping chamber (60), a plunger (36) extending through the pumping chamber, a high pressure side-seal (58) and a low pressure side-seal (56) provided in slide contact with the plunger for preventing leakage of fluid from the pumping chamber, an annular and sealing through which a plunger (36) slidably extends into the pumping chamber (60), and an annular space (62) being defined between the high pressure side-seal (58) and the low pressure side-seal (56) so that it can receive liquid from a suction port (74) for lubrication of the plunger. Even when the plunger pump section (34) is installed at a predetermined or any circumferencial position, air is intended to be vented from the annular space (62). For this purpose, three circumferencially spaced channels (78) are formed in an inner wall of a manifold member (18) surrounding a sleeve (52) defining the pumping chamber (60) and communicate at their ends with the suction port (74) and (62).
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: April 25, 2000
    Assignee: Maruyama Mfg. Co., Inc.
    Inventor: Nobuo Tojo
  • Patent number: 4875690
    Abstract: A sealing device for a reciprocating pump of the type having a pump housing provided with a bore formed therein. The bore is provided at its one end with an opening through which it communicates with the exterior of the pump housing while the other end of the bore receives a reciprocating member such as a plunger. The sealing device includes a seal case received in the bore and having a bore through which the reciprocating member extends, a sealing member such as a packing held on the inner periphery of the seal case and having an inner peripheral surface adapted to be slidingly contacted by the outer peripheral surface of the reciprocating member, a closure separate from the pump housing and removably attached to the pump housing so as to close the opening on the one end of the bore, and a coiled compression spring loaded between the closure and either one of the seal case and the sealing member.
    Type: Grant
    Filed: April 5, 1988
    Date of Patent: October 24, 1989
    Assignee: Maruyama Mfg. Co. Inc.
    Inventor: Nobuo Tojo
  • Patent number: D538824
    Type: Grant
    Filed: May 16, 2006
    Date of Patent: March 20, 2007
    Assignee: Maruyama Mfg. Co., Inc.
    Inventor: Nobuo Tojo
  • Patent number: D495342
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: August 31, 2004
    Assignee: Maruyama Mfg. Co., Inc.
    Inventors: Nobuo Tojo, Toshiaki Ohnishi
  • Patent number: D591311
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: April 28, 2009
    Assignee: Maruyama Mfg. Co., Inc.
    Inventor: Nobuo Tojo