Ngk Spark Plug Company, Limited

Satoshi Ishikawa

Kouji Matsuo

Shoji Akatsuka

Masahiro Asai

Masamichi Ito

Takayoshi Atsumi

Shoichi Ohtsuki

Satoshi Mogari

Takehiro Oba

Takaya Yoshikawa

Nobuhiro Hayakawa

Hiroshi Miyata

Kunihiko Yonezu

Hiromichi Hayashi

Tomohiro Tajima

Yoshiro Noda

Takafumi Shichida

Tatsuya Okumura

Takashi Nakashima

Takashi Mizukusa

Tomohiko Funahashi

Shoich Ohtsuki

Syogo Kawajiri

Koji Matsuo

A sensor control apparatus including a gas sensor having a sensor element, a housing and a base part formed of a resin. The apparatus includes a heating part and a control part. When the control part determines that a predetermined automatic stop condition has been satisfied, the control part switches from a control for maintaining the temperature of the sensor element at an activating temperature to a control in a stop state for reducing at least one of voltage and current supplied to the heating part so as to set a temperature of the base part to a value equal to or lower than a shape holding temperature of the resin. Also disclosed is a sensor control method for holding a temperature of a sensor element to an activating temperature.

Sensor control apparatus and sensor control method

A sensor including a tube having a small-diameter portion loosely inserted into a tube insertion hole of an annular mounting fixture and a large-diameter portion having a diameter larger than an inside diameter of the tube insertion hole. A flow path is formed, so that when the large-diameter portion of the tube is locked on the rear end of the tube insertion hole, a rear end of a gap, defined between an inner circumferential surface of the tube insertion hole and an outer circumferential surface of the small-diameter portion of the tube, remains open. Further, the inner circumferential surface of the tube insertion hole and the outer circumferential surface of the small-diameter tubular portion of the tube are brazed together with a brazing filler which flows into the gap.

Temperature sensor having a flow path for a brazing filler to flow between an outer surface of the tube and an inner surface of the mounting structure

A temperature sensor () includes a heat-sensitive element () having a thermistor sintered-body (), an insulating support (), an insulation sheath () and a housing tube (). The insulating support () is in contact with the rear end of the heat-sensitive element () and the insulation sheath () is in contact with the rear end of the insulating support (). The housing tube () accommodates the heat-sensitive element (), the insulating support () and the insulation sheath (). The housing tube () includes a sheath accommodation portion () which accommodates the insulation sheath () and a distal accommodation portion (). The distal accommodation portion () is located toward the distal end of the housing tube () with respect to the sheath accommodation portion (), is smaller in outside diameter than the sheath accommodation portion (), and accommodates at least half of the insulating support () as measured from the axially distal end of the insulating support ().

Temperature sensor

A sensor () is configured such that a seal member () is provided in a deformed manner through crimping of a portion of a tube () located toward a rear end () of the tube (). The seal member () is deformed such that a frontward-oriented surface (), which is a bottom surface of a recess () formed in a front end () of the seal member (), presses a rear end () of an insulation sheath () frontward. Consequently, a front end () of a sensor element is pressed against a front end () of the tube () via the insulation sheath (). By virtue of a pressing action induced by rubber-like elasticity, high sensor responsiveness is maintained over a long period of time.

The present invention provides a sensor capable of maintaining an electrical connection between the lead frame and an electrode terminal section of the detection element even when an inadequate external force is applied to a lead frame and a sensor production method capable of preventing the lead frame from buckling and being deformed into an inadequate shape. The lead frame (second lead frame) can inhibit movement of a second frame main body section axially toward a rear end side through engagement of a third locking surface of a second locking section with a second locking groove and can inhibit the second frame main body section from going apart from an inner surface of an insertion hole through engagement of a fourth locking surface of the second frame locking section, which faces an element engagement section side. Namely, even when an external force is applied to the lead frame, movement of the lead frame main body section (second lead frame main body section) can be inhibited and a variation in the relative positions of the lead frame and the detection element can be prevented.

Sensor and method of producing sensor

In a method of manufacturing a sensor, firstly, a plate-type detection element is inserted through an element-insertion through-hole of a first powder-compacted ring. Secondly, a flange section including at least the first powder-compacted ring is integrally assembled to the plate-type detection element, applying axially compressive pressure to the first powder-compacted ring so as to compressively deform the first powder-compacted ring such that the cross-sectional area of the element-insertion through-hole is reduced. Thirdly, the flange section is engaged, directly or via an intermediate member, with the stepped portion of the metallic shell at the time of disposing of the plate-type detection element in the through-hole of the metallic shell. A sensor prepared by the method is also disclosed.

Gas sensor with sealing structure

A detecting element () of a gas sensor () is held with a detecting portion () projecting from a front-end engaging-portion () of a metallic shell () and is accommodated for protection in an inner protector () in a gas detection chamber (). Exhaust gas introduced into the gas detection chamber () is exhausted through an exhaust hole (). The exhaust hole is formed by cutting off a portion of a side wall () of a recess portion (), which is formed by pressing inward a portion between two slits formed in a front end wall (). A bottom wall () of the recess portion () is located frontward of the detecting element () with respect to the direction of an axis O, thereby preventing a water droplet which comes flying from the outside from directly contacting the detecting element ().

Gas sensor

The present invention provides a sensor and a method of producing the same, which makes an electrical connection condition between an electrode terminal section of a detection element and a metallic terminal member good. The sensor includes a lead frame (metallic terminal member) that changes a support condition of supporting an element abutment section for contact with a detection element on a frame main body section, into a one-point support or a two-point support. At a first-half stage of a work for assembly of the lead frame and the detection element, the element abutment section is put in a one-point support condition relative to the frame main body section and the lead frame produces a relatively smaller resilient force, such that it becomes possible to prevent an excessively large pressure from being applied to the detection element. After the assembly work is completed, the element abutment section is put in a two-point support condition relative to the frame main body section and the lead frame produces a larger resilient force as compared with that in the one-point support condition, such that the electrical connection condition between the lead frame and the detection element can be good.

A gas sensor is constructed as follows. A protector () covering around a gas sensing element () has an inner hollow-cylindrical portion () and an outer hollow-cylindrical portion () that is provided coaxially with the inner hollow-cylindrical portion () with an air space () in between. Outer-wall gas inlet openings () are formed in the outer hollow-cylindrical portion (), and guiding bodies () extending inward are attached to the outer-wall gas inlet openings (). Inner-wall gas inlet openings () are formed in the inner hollow-cylindrical portion () at positions nearer to the gas sensing element () than the outer-wall gas inlet openings (). A side wall () face of the inner hollow-cylindrical portion () opposite the outer-wall gas inlet openings () is formed so as to be parallel to a side wall () of the outer-hollow cylindrical portion () or so as to have a slop-like shape with a diameter enlarging in the axial direction toward a bottom wall () of the protector (). A discharge opening () for a gas to be measured is formed in the bottom wall ().

Method of manufacturing sensor and sensor

An oxygen sensor as a gas sensor has a vent hole for taking an atmosphere into an outer sleeve in an outer sleeve cover for covering the outer sleeve from above and manufactured by rubber. A filter unit made by a tubular member enlarged in diameter on a predetermined boundary, a sheet-shaped filter having a water repellent property and an oil repellent property, and an O-ring is fitted and inserted into this vent hole. The upper end portion of a large diameter portion is folded by bending processing. Folding portion nips and supports the filter and the O-ring between the folding portion and a step portion formed between a large diameter portion and a small diameter portion. It is sufficient to set the size of a filter to same size as the vent hole. The filter can be attached to a predetermined position of the outer sleeve cover.

A gas sensor is provided which comprises a sensor element for detecting a component of a gas and a cup-shaped protector for covering a detecting section of the sensor element. The protector is dual-walled and have cup-shaped inner and outer protector members. The inner and outer protector members are constructed and arranged so that g >g where g is the distance between an inner surface of a circumferential wall of the outer protector member and an outer surface of a circumferential wall of the inner protector member and g is the distance between an inner surface of a bottom wall of the outer protector member and an outer surface of a bottom wall of the inner protector member. The outer protector member has at the circumferential wall thereof a plurality of first gas holes. The inner protector member has at the circumferential wall thereof a plurality of second gas holes.

A gas sensor is provided which comprises a sensor element for detecting a component of a gas and a cup-shaped protector for covering a detecting section of the sensor element. The protector is dual-walled and have cup-shaped inner and outer protector members. The inner and outer protector members are constructed and arranged so that g1>g2 where g1 is the distance between an inner surface of a circumferential wall of the outer protector member and an outer surface of a circumferential wall of the inner protector member and g2 is the distance between an inner surface of a bottom wall of the outer protector member and an outer surface of a bottom wall of the inner protector member. The outer protector member has at the circumferential wall thereof a plurality of first gas holes. The inner protector member has at the circumferential wall thereof a plurality of second gas holes. When the direction of a tip end of the sensor element is referred to as forward, the first gas holes are disposed forward of the second gas holes. A front end of the sensor element is disposed forward of the second gas holes. The inner and outer protector members have at bottom walls thereof bottom gas holes.

A sensor structure having a metallic terminal member. The metallic terminal member includes press portions and , which press the heating member in a direction intersecting the center axis of a hollow portion of an oxygen detection element . Holding means for holding the heating member is formed separately from the metallic terminal member . Thus, without use of special heating-member holder means, the metallic terminal member can bring at least a portion of the heating member into contact with the inner wall surface of the hollow portion of the oxygen detection element

Growing community of inventors

Aichi, Japan

Satoshi Ishikawa