Abstract:
An exhaust gas control apparatus includes a PM trapping filter provided in an exhaust gas passage of an internal combustion engine, an oxygen concentration sensor provided upstream of the filter, a device that estimates the air-fuel ratio of exhaust gas supplied to the oxygen concentration sensor, and a device that estimates the amount of PM trapped in the filter based on the estimated exhaust gas air-fuel ratio and the oxygen concentration sensor output. The amount of PM trapped in the filter is estimated using the fact that the oxygen concentration sensor output value changes according to the exhaust gas air-fuel ratio and the amount of PM accumulated on the oxygen concentration sensor. As a result, the structure of the exhaust passage is able to be kept simple because only an oxygen concentration sensor is added upstream of the filter.
Abstract:
An object of the present invention is to provide a technology that enables to detect a fault of a PM trapper with improved accuracy. According to the present invention, a plurality of temperature sensors 10 are provided in an exhaust passage 9 just downstream of a PM trapper 17 in such a way that their temperature detection elements are positioned on a plane that is perpendicular to an imaginary center axis of the exhaust passage 9. A change in the radial direction temperature distribution of the exhaust gas flowing out of the PM trapper 17 upon occurrence of a fault in the PM trapper 17 is detected from measurement values of the temperature sensors 10, and a fault of the PM trapper 17 is detected based on this radial direction temperature distribution. Since the measurement values of the temperature sensors 10 are unlikely to be affected by the amount of PM deposited on the PM trapper 17, detection of a fault of the PM trapper 17 can be achieved with improved accuracy.
Abstract:
In a compression ignition internal combustion engine provided with an NOx storage-reduction catalyst on an exhaust system, when the air fuel ratio of the exhaust gas being in a lean state is controlled to a rich state, a response time (ResS) from a time point an air fuel ratio sensor detects a first air fuel ratio (AF1), which is leaner than a stoichiometric air fuel ratio (AFS), to a time point the air fuel ratio sensor detects a second air fuel ratio (AF2), which is equal to or leaner than the stoichiometric air fuel ratio (AFS) and richer than the first air fuel ratio (AF1). When the response time (ResS) exceeds a stoichiometric air fuel ratio shift reference time (StdS), a determination is made that the air fuel ratio sensor is degraded.
Abstract:
A cubic boron nitride sintered material where wear resistance is suppressed from decreasing having excellent chipping resistance and a cutting tool made thereof are provided. The sintered material is constituted from cubic boron nitride particles that are bound by a binder phase, while the binder phase contains a carbide of at least one kind of metal element selected from among metals of groups 4, 5 and 6 of the periodic table and a nitride of at least one kind of metal element selected from among metals of groups 4, 5 and 6 of the periodic table coexisting therein, and therefore the particles can be suppressed from coming off and the binder phase can be suppressed from wearing and coming off at the same time, thereby making the sintered material having high wear resistance and particularly excellent chipping resistance.
Abstract:
There is provided a cemented carbide comprising a hard phase component which comprises a tungsten carbide (WC) and at least one selected from carbides, nitrides and carbonitrides of metals of the groups 4a, 5a and 6a in the periodic table; and a binder phase component comprising at least one of iron-group metals, wherein the surface region of the cemented carbide has 90–98% of the minimum hardness as compared with internal hardness, thereby having high hardness and toughness which is suitable to using as a cutting tool.
Abstract:
An exhaust emission control apparatus for an internal combustion engine is capable of suppressing a nasty smell due to the hydrogen sulfide generated upon recovery from SOx poisoning. The exhaust emission control apparatus includes an NOx storage-reduction catalyst, a reducing agent supplying section for supplying a reducing agent to the NOx catalyst, an SOx poisoning recovering section for recovering the NOx catalyst from its SOx poisoning by varying the oxygen concentration of an exhaust by means of reducing agent supplying section, a hydrogen sulfide concentration estimating section for estimating a concentration of hydrogen sulfide in an atmosphere into which the hydrogen sulfide is discharged, and an estimated concentration derived reducing agent supply amount control section for decreasing an amount of reducing agent to be supplied in accordance with the increasing concentration of hydrogen sulfide estimated by the hydrogen sulfide concentration estimating section while the NOx catalyst is recovered from the sulfur oxide poisoning.
Abstract:
A composite construction 1 is obtained by coating the outer periphery of a core material 2 with a shell layer 3. The core material 2 is composed of a first sintered body that is obtained by bonding, with a binder metal, a first hard particle composed of one or more of carbides, nitrides and carbonitrides of metals of Groups 4a, 5a and 6a of the Periodic Table, or a first ceramics obtained by bonding, with a sintering additive, a first ceramic particle composed of at least one of oxides, carbides, nitrides and carbonitrides selected from the group consisting of metals of Groups 4a, 5a and 6a of the Periodic Table, Al, Si and Zn. The shell layer 3 is composed of a second hard sintered body or second ceramics having a different composition from the first hard sintered body. The ratio of the residual free carbon amount Cin in the core material 2 to the residual free carbon amount Cout in the shell layer 3, Cin/Cout, is 0.5 to 2. This prevents shrinkage during the time of sintering and also prevents the strength of the composite construction from lowering due to poor sintering.
Abstract:
The cutting member comprises WC, two or more solid solutions of WC and compounds selected from carbides, nitrides and carbonitrides of metals of the groups 4a, 5a and 6a in the Periodic Table, and at least one metal of the iron group; and at least one of the two or more solid solutions being a solid solution having a high Nb or Zr content, whereby the wear resistance and plastic deformation resistance are improved in case of cutting hardly machinable materials such as stainless steel, thereby making it possible to prolong the service life of the cutting member.
Abstract:
A device for providing cutaneous sensations to a fingertip 10 includes a lower base, an upper platform positioned over and mechanically connected to the lower base, and a shear plate positioned between the lower 36 base and the upper platform and mechanically connected to the lower base. When a fingertip is positioned between the upper platform and the lower base, the upper platform is selectively vertically translatable relative to the lower base to provide a compressive force, and the shear plate is selectively laterally translatable relative to the lower base to provide a shear force. Accordingly, a wearable fingertip device having two degrees-of-freedom (DoF) to provide consecutive and/or concurrent compressive force and/or shear force to a fingertip is provided. The wearable fingertip device can be used in various scenarios; is portable, easily wearable, and easily manufacturable; and has low overall operating power requirements.
Abstract:
An exhaust gas purification apparatus including a filter, an NOx selective reduction catalyst at the downstream side of the filter, a supply device for supplying a reducing agent to the NOx selective reduction catalyst, and a PM sensor for detecting an amount of particulate matter in an exhaust gas at the downstream side of the NOx selective reduction catalyst. A supply decrease part makes an amount of supply of the reducing agent smaller in cases where at least one of several conditions is satisfied.