Kabushiki Kaisha Riken

Yongtie Yan

Akira Kunimoto

Masaharu Hasei

Takashi Ono

Yunzhi Gao

Yukio Nakanouchi

Hideyuki Kurosawa

Norio Miura

Noboru Yamazoe

Hayato Sasaki

Takashi Okamoto

Provided is a piston ring for an internal combustion engine capable of preventing aluminum cohesion for a long time under conditions with high temperature and a high load and also suppressing the wearing of a piston member. A piston ringfor the internal combustion engine including a piston ring bodyhaving at least one of an upper side face and a lower side face coated with an aluminum cohesion resistance film, wherein the aluminum cohesion resistance filmhas a first coating filmmade of first ceramics material formed on the piston ring body and a second coating film having Vickers hardness HV smaller than that of the first ceramics material formed on the first coating film

Piston ring for internal combustion engine

A gas-detecting element comprising an oxygen-ion-conductive solid electrolyte substrate, a sensing electrode fixed onto said solid electrolyte substrate and active with a detection object gas and oxygen, and a reference electrode fixed onto said solid electrolyte substrate and active with at least oxygen, for detecting potential difference between the sensing electrode and the reference electrode to determine the concentration of the detection object gas, the sensing electrode and/or the reference electrode being covered by an electrode-coating layer made of an oxygen-ion-conductive solid electrolyte, and the electrode-coating layer having a portion bonded to the solid electrolyte substrate directly or via an electrode underlayer made of an oxygen-ion-conductive solid electrolyte.

Gas-detecting element and gas-detecting device comprising same

The present invention discloses a gas sensing device, an oxygen pumping cell, and a gas detection apparatus using the same for detecting lower ranges of gas concentration with high accuracy and stability. An under layer made of oxygen-ion-conductive solid electrolyte was formed between an electrolyte substrate and a sensing electrode, a conversion electrode or a gas treatment electrode. This allows the physical and chemical adhesion between these electrodes and the electrolyte substrate, thereby improving the sensing properties and stability.

Gas sensing and oxygen pumping device, and apparatus using the same

A gas sensor for measuring concentration of a gas component in a measured gas, including a solid electrolytic substrate and at least two electrodes fixed to the substrate. At least a first electrode of the electrodes is disposed in the environment of the measurement gas, at least one of electrodes is polarized by applying a bias current or bias voltage, and a change in the potential of the polarized electrode is measured to thereby measure the concentration of the target gas.

Measuring NOx concentration

A nitrogen oxide gas sensor wherein an alloy electrode of platinum and rhodium or a cermet electrode of platinum, rhodium, and zirconia or of a rhodium alloy and zirconia is used as the gas sensing electrode. The electrode of the sensor is suitable for measuring nitrogen oxide such as NO and NO in an exhaust gas.

Nitrogen oxide gas sensor

A nitrogen oxide sensor enabled to enhance the measurement concentration of a total of nitrogen oxides by oxidizing or reducing the nitrogen oxides on the surfaces of electrodes in addition to the control of an oxygen concentration by an oxygen pump. An electrode (,) in a gas chamber (,) constructing an oxygen pumping portion (,) is made of a material (e.g., Pt-3 wt % Rh) having a function to oxidize a nitrogen oxide gas.

Nitrogen oxide sensor

A nitrogen oxide sensor includes a solid electrolytic substrate exhibiting oxygen ion conductivity, a noble-metal reference electrode, which is active only to oxygen, formed on one side of the solid electrolytic substrate, and a sensing electrode, which is active to NOx and oxygen, formed on the opposite side of the solid electrolytic substrate. A potential difference across the sensing electrode and the reference electrode is output as a signal indicative of NOx concentration. Nitrogen oxides in a gas to be examined or measured gas are converted to NO,and to peroxides of nitrogen such as N,O,and NO,, after which the nitrogen oxides in the gas to be examined or measured gas are sensed by the sensing electrode as the peroxides of nitrogen such as N,O,and NO,or as a mixed gas of NO,and the peroxides of nitrogen.

Gas sensor

A stable sensor designed to detect accurately the total NOx concentration under 100 ppm in terms of the NO gas concentration is made up of a first cell and a second cell with a gas diffusion aperture provided between the two cells. The first cell has a partition wall of a substrate of oxygen ion conductor containing zirconia as the main component and permitting a gas to be detected to enter the zirconia substrate; oxygen pumping electrodes are also formed on the first cell substrate which functions to expel oxygen in an atmosphere of the first cell to the outside and to reduce NO.sub.2 of the NOx gas to be detected to NO gas. While NO gas entering through a gas diffusion aperture between the two cells flows into the second cell, a measurement is made of an electromotive force between a NO detection electrode formed in the second cell and a counter electrode also formed therein or a counter electrode formed on the reverse side of the zirconia substrate, since such electromotive force corresponds to the level of the NO gas concentration and thus provides the total NOx concentration.

Growing community of inventors

Kumagaya, Japan

Yongtie Yan