Patents by Inventor Tetsuji Nobuta

Tetsuji Nobuta 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: 7096930
    Abstract: In a condenser of a refrigerant cycle, a throttle portion is provided at a predetermined position in one of first and second header tanks to decompress refrigerant while refrigerant meanderingly flows within the one of the first and second header tanks. Therefore, refrigerant from the throttle portion is sufficiently mixed with refrigerant directly flowing from tubes into a downstream space of the throttle portion in the one of the first and second header tanks. Accordingly, even when gas refrigerant is directly introduced from a part of the tubes directly into the lower downstream space, the gas refrigerant can be effectively heat-exchanged with the refrigerant flowing from the throttle portion. As a result, it can restrict refrigerant from being discharged from the condenser in a gas-liquid two-phase state.
    Type: Grant
    Filed: July 20, 2004
    Date of Patent: August 29, 2006
    Assignee: DENSO Corporation
    Inventors: Tetsuji Nobuta, Naoki Sugimoto, Ryouichi Sanada, Tatsuhiko Nishino
  • Publication number: 20050039893
    Abstract: In a condenser of a refrigerant cycle, a throttle portion is provided at a predetermined position in one of first and second header tanks to decompress refrigerant while refrigerant meanderingly flows within the one of the first and second header tanks. Therefore, refrigerant from the throttle portion is sufficiently mixed with refrigerant directly flowing from tubes into a downstream space of the throttle portion in the one of the first and second header tanks. Accordingly, even when gas refrigerant is directly introduced from a part of the tubes directly into the lower downstream space, the gas refrigerant can be effectively heat-exchanged with the refrigerant flowing from the throttle portion. As a result, it can restrict refrigerant from being discharged from the condenser in a gas-liquid two-phase state.
    Type: Application
    Filed: July 20, 2004
    Publication date: February 24, 2005
    Inventors: Tetsuji Nobuta, Naoki Sugimoto, Ryouichi Sanada, Tatsuhiko Nishino
  • Patent number: 6698235
    Abstract: A refrigerant cycle system includes a condenser having a condensation portion for condensing refrigerant discharged from a compressor, and a receiver for separating refrigerant from the condensation portion into gas refrigerant and liquid refrigerant, and for storing the liquid refrigerant. In this system, refrigerant from the condensation portion flows into the receiver through a first communication hole, and liquid refrigerant in the receiver is discharged through a second communication hole in which a pressure loss is generated. Further, gas refrigerant at an upper side in the receiver is discharged to a downstream side of the second communication hole through a gas bypass pipe.
    Type: Grant
    Filed: September 9, 2002
    Date of Patent: March 2, 2004
    Assignee: Denso Corporation
    Inventors: Tetsuji Nobuta, Ryouichi Sanada, Satoshi Sumiya
  • Patent number: 6681582
    Abstract: A vapor compression type refrigeration apparatus is provided, in which refrigerant leakage is detected at an early stage. A temperature difference related to the theoretical heat dissipation of the condenser is compared with the actual temperature difference in heat dissipation (temperature difference between the condensation temperature and the outside-air temperature) of the condenser to determine whether there is a refrigerant leak.
    Type: Grant
    Filed: April 2, 2002
    Date of Patent: January 27, 2004
    Assignee: Denso Corporation
    Inventors: Takahisa Suzuki, Tatsuo Tsunooka, Toshihiro Tahara, Tetsuji Nobuta
  • Publication number: 20030051503
    Abstract: A refrigerant cycle system includes a condenser having a condensation portion for condensing refrigerant discharged from a compressor, and a receiver for separating refrigerant from the condensation portion into gas refrigerant and liquid refrigerant, and for storing the liquid refrigerant. In this system, refrigerant from the condensation portion flows into the receiver through a first communication hole, and liquid refrigerant in the receiver is discharged through a second communication hole in which a pressure loss is generated. Further, gas refrigerant at an upper side in the receiver is discharged to a downstream side of the second communication hole through a gas bypass pipe.
    Type: Application
    Filed: September 9, 2002
    Publication date: March 20, 2003
    Inventors: Tetsuji Nobuta, Ryouichi Sanada, Satoshi Sumiya
  • Patent number: 6530239
    Abstract: A refrigeration system which can reduce the amount of moisture permeating into the system, inexpensively and by a simple structure, is disclosed. Rubber hoses (7, 8) capable of absorbing vibrations are arranged on the discharge and the intake sides of a compressor (1). It was found that the amount of moisture in the system can be effectively reduced by reducing the amount of moisture permeating the rubber hose on the discharge side. A freezing limit line is set for defining to a predetermined level the amount of moisture in the system determined by the amount of the refrigerant sealed in the system, the amount of the lubricating oil sealed in the system, the amount of moisture permeation of the hoses (7, 8) and the number of the years elapsed after operation start. The hose (7) on the discharge side of the compressor has a smaller amount of moisture permeation than the hose (8) on the intake side.
    Type: Grant
    Filed: November 13, 2001
    Date of Patent: March 11, 2003
    Assignee: Denso Corporation
    Inventors: Tetsuji Nobuta, Keiichi Kitamura
  • Patent number: 6477858
    Abstract: The refrigerant cycle apparatus comprises a communication pipe 32 which is an upper refrigerant flow-in means allowing the refrigerant which has passed through a condenser 2 to flow into the upper part of a liquid receiver 31, and a communication hole 33 which is a lower refrigerant flow-in means allowing the refrigerant which has passed through the condenser 2 to flow into the lower part of the liquid receiver 31, and the flow rate (Gr1) of refrigerant flowing into the upper part of the liquid receiver 31 from the communication pipe 32 is set at a value between 30 kg/h and 110 kg/h. As a result of this, preventing heat damage due to the heat given to the liquid receiver from the outside and securing the good bubble disappearing characteristic of the liquid refrigerant flowing out from the liquid receiver are mutually compatible, and thereby an improved refrigerant filling characteristic may be obtained.
    Type: Grant
    Filed: November 19, 2001
    Date of Patent: November 12, 2002
    Assignee: Denso Corporation
    Inventors: Tetsuji Nobuta, Takahisa Suzuki, Keisuke Nagai
  • Publication number: 20020139128
    Abstract: A vapor compression type refrigeration apparatus is provided, in which refrigerant leakage is detected at an early stage. A temperature difference related to the theoretical heat dissipation of the condenser is compared with the actual temperature difference in heat dissipation (temperature difference between the condensation temperature and the outside-air temperature) of the condenser to determine whether there is a refrigerant leak.
    Type: Application
    Filed: April 2, 2002
    Publication date: October 3, 2002
    Inventors: Takahisa Suzuki, Tatsuo Tsunooka, Toshihiro Tahara, Tetsuji Nobuta
  • Patent number: 6397627
    Abstract: In a receiver-integrated condenser, a super-cooling portion for cooling liquid refrigerant from a receiving unit is disposed between first and second condensing portions in a core portion in a vertical direction. Therefore, in an engine-idling, even when high-temperature air having passed through the receiver-integrated condenser is introduced again toward an upstream air side of the receiver-integrated condenser through a lower side of the receiver-integrated condenser, the high-temperature air is not introduced toward the arrangement position of said super-cooling portion, because the super-cooling portion is positioned at an upper side from the second condensing portion. Thus, super-cooling performance of refrigerant in the super-cooling portion of the core portion is prevented from being decreased even in the engine idling.
    Type: Grant
    Filed: March 3, 2000
    Date of Patent: June 4, 2002
    Assignee: Denso Corporation
    Inventors: Yoshifumi Aki, Etuo Hasegawa, Hiroki Matsuo, Tetsuji Nobuta, Michiyasu Yamamoto, Mitsukawa Kazuhiro, Eiji Okabayashi
  • Publication number: 20020059806
    Abstract: The refrigerant cycle apparatus comprises a communication pipe 32 which is an upper refrigerant flow-in means allowing the refrigerant which has passed through a condenser 2 to flow into the upper part of a liquid receiver 31, and a communication hole 33 which is a lower refrigerant flow-in means allowing the refrigerant which has passed through the condenser 2 to flow into the lower part of the liquid receiver 31, and the flow rate (Gr1) of refrigerant flowing into the upper part of the liquid receiver 31 from the communication pipe 32 is set at a value between 30 kg/h and 110 kg/h.
    Type: Application
    Filed: November 19, 2001
    Publication date: May 23, 2002
    Inventors: Tetsuji Nobuta, Takahisa Suzuki, Keisuke Nagai
  • Publication number: 20020056284
    Abstract: A refrigeration system which can reduce the amount of moisture permeating into the system, inexpensively and by a simple structure, is disclosed. Rubber hoses (7, 8) capable of absorbing vibrations are arranged on the discharge and the intake sides of a compressor (1). It was found that the amount of moisture in the system can be effectively reduced by reducing the amount of moisture permeating the rubber hose on the discharge side. A freezing limit line is set for defining to a predetermined level the amount of moisture in the system determined by the amount of the refrigerant sealed in the system, the amount of the lubricating oil sealed in the system, the amount of moisture permeation of the hoses (7, 8) and the number of the years elapsed after operation start. The hose (7) on the discharge side of the compressor has a smaller amount of moisture permeation than the hose (8) on the intake side.
    Type: Application
    Filed: November 13, 2001
    Publication date: May 16, 2002
    Inventors: Tetsuji Nobuta, Keiichi Kitamura
  • Patent number: 6374632
    Abstract: In a receiver for separating gas refrigerant and liquid refrigerant and for storing liquid refrigerant for a refrigerant cycle, refrigerant form a condensing portion of a condenser flows into an upper side of a tank member of the receiver from a first refrigerant inlet and flows into a lower side of the tank portion from a second refrigerant inlet. Further, liquid refrigerant stored in the tank member of the receiver is discharged to an outside through a refrigerant outlet. Accordingly, refrigerant from the condensing portion of the condenser flows into the tank portion of the receiver from both upper and lower sides of a gas-liquid boundary surface. As a result, it can prevent the gas-liquid boundary surface of the receiver from being disturbed during a refrigerant introduction of the receiver, while cooling effect of the upper side of the receiver is effectively improved.
    Type: Grant
    Filed: September 27, 2000
    Date of Patent: April 23, 2002
    Assignee: Denso Corporation
    Inventors: Tetsuji Nobuta, Hiroki Matsuo, Kazuya Makizono
  • Patent number: 6341647
    Abstract: A separator-integrated condenser includes a core portion, a header tank and a separating unit integrally formed with the header tank for separating gas-liquid two-phase refrigerant into gas refrigerant and liquid refrigerant and storing the liquid refrigerant therein. An inlet through which refrigerant in the header tank is introduced into the separating unit is disposed at one longitudinal end of the separating unit, and an outlet through which refrigerant is discharged from the separating unit is disposed at the other longitudinal end of the separating unit. When the condenser is mounted to be inclined at up to 45 degrees with respect to a horizontal direction in a longitudinal direction of the header tank and the separating unit, the inlet is disposed at an upper side of the outlet. As a result, gas-liquid two-phase refrigerant is sufficiently separated by the separating unit.
    Type: Grant
    Filed: February 2, 2000
    Date of Patent: January 29, 2002
    Assignee: Denso Corporation
    Inventors: Tetsuji Nobuta, Hiroki Matsuo
  • Patent number: 6192838
    Abstract: An engine cooling apparatus suitable for use in a vehicle shortens engine warm-up time without decreasing the heat-radiation capacity of a radiator. A shroud is disposed between a radiator and a water-cooled engine. A first air passage for blowing air toward the engine and its auxiliaries is formed in the upper side of the shroud, and a second air passage for discharging air having passed through the radiator to outside the engine compartment is formed in the lower side of the shroud. Accordingly, air is prevented from directly striking the engine and from passing around to the upstream side of the radiator through gaps between the walls of the engine compartment and the radiator. Thus the engine warm-up time is shortened without reducing the heat-radiation capacity of the radiator.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: February 27, 2001
    Assignee: Denso Corporation
    Inventors: Hiroki Matsuo, Tetsuji Nobuta, Kazuya Makizono, Toshio Morikawa, Hikaru Sugi, Shun Kurata, Manabu Miyata, Koji Ito
  • Patent number: 6016662
    Abstract: A main evaporator cools a driver's compartment of a vehicle while a cooling storage evaporator cools cooling storage packs that are used in cooling a sleeping compartment. Refrigerant is supplied to the main evaporator at the actuation of a first solenoid valve while refrigerant is supplied to the cooling storage evaporator at the actuation of a second solenoid valve. If a first switch is being actuated after the completion of the cooling storage operation of the cooling storage evaporator on the cooling storage packs and the temperature of the cooling storage packs is no more than a preset temperature, for example, -5.degree. C., FIR control is performed for alternately actuating the first solenoid valve and the second solenoid valve based on a predetermined time ratio (for example, 10 minutes 15 seconds).
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: January 25, 2000
    Assignee: Denso Corporation
    Inventors: Hisashi Tanaka, Yuichi Shirota, Hiroki Matsuo, Hikaru Sugi, Masami Konaka, Kazushi Yamamoto, Seiji Miwa, Tetsuji Nobuta
  • Patent number: 5927102
    Abstract: A receiver-integrated condenser for a refrigerating system for use in an automotive vehicle is disclosed. The condenser is composed of a heat exchanging core having many tubes extending horizontally in which refrigerant is cooled down and condensed, a pair of header tanks elongated vertically and connected to both ends of the tubes, and a refrigerant receiver for reserving liquid refrigerant therein integrally connected to one of the header tanks which has an inlet joint for receiving overheated refrigerant from a compressor. The inner space of the header tank to which the receiver is connected is divided by a separator into an upper space for receiving the overheated refrigerant and a lower space for receiving refrigerant cooled down in the heat exchanging core. The receiver is connected integrally to the header tank so that it does not overlap with the upper space of the header tank in order to minimize heat transfer from the upper space to the receiver.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: July 27, 1999
    Assignee: Denso Corporation
    Inventors: Hiroki Matsuo, Tetsuji Nobuta
  • Patent number: 5875650
    Abstract: In a refrigerant condenser including a super-cooling portion, the super cooling portion is located in the upper position of a core portion. Thus, when a vehicle engine idles, and high temperature cooling air having passed through the refrigerant condenser and the vehicle radiator is lead to the air upstream side of the condenser through the lower portion of the condenser, because the super-cooling portion is located at the upper position of the core portion, the super-cooling portion is not influenced by the high temperature air.
    Type: Grant
    Filed: July 6, 1998
    Date of Patent: March 2, 1999
    Assignee: Denso Corporation
    Inventors: Tetsuji Nobuta, Hiroki Matsuo, Masahiro Shimoya, Michiyasu Yamamoto, Etuo Hasegawa
  • Patent number: 5713213
    Abstract: Deficiency in the amount of a refrigerant in a refrigeration cycle device is determined based on the amount of decrease in the temperature of an evaporator after a predetermined time period elapses since the actuation of a compressor. The execution of the process for determining deficiency in the amount of refrigerant is prohibited for predetermined time period after the deactuation of the compressor. Therefore, when the temperature of the evaporator does not increase enough after the compressor is actuated, erroneous determination that there is a deficiency in the refrigerant amount can be reliably prevented. In this way, deficiency in the amount of refrigerant in the refrigeration cycle can always be properly determined based on an amount of decrease in the temperature of the evaporator.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: February 3, 1998
    Assignee: Denso Corporation
    Inventors: Tetsuji Nobuta, Hisayoshi Sakakibara