Jtekt Corporation

Toyoda Koki Kabushiki Kaisha

Diamond Electric Mfg. Co., Ltd.

Toyoda Van Moppes Ltd.

Hiroshi Morita

Shinji Soma

Takayuki Yoshimi

Yoshihiro Mizutani

Toshihiro Yonezu

Tomoyuki Kasuga

Ryohei Mukai

Akira Makiuchi

Yuki Ishigure

Tomokazu Yamashita

Kohei Adachi

Kazutoshi Hosoda

Takafumi Furutate

Yuuta Kobayashi

Yasuhira Yamada

Atsushi Sawa

Kimihiro Ban

Shinichi Yokota

Hiroyuki Shibata

Takuya Murao

This ignition coil includes: a bar-shaped resistor electrically connected to a terminal of a coil assembly via a relay; a case for storing these; and a filler filling gaps inside the case. The case includes a body, a cylindrical output portion protruding from the body, and an annular holding portion protruding inward from an inner circumferential surface of the output portion and formed integrally with the output portion. A part of the resistor is inserted into the holding portion, and thus a first internal area located on the body side with respect to the holding portion and shut off from outside is formed in an internal area of the output portion. The filler fills the first internal area.

Ignition coil

This igniter assemblyincludes: an igniterprovided with a lead terminal; a bodymade of resin and storing the igniter; and an internal terminalfixed to the bodyand having one end electrically connected to the lead terminal. The internal terminalhas another end extending outward of the body

Igniter assembly and igniter unit

A wheel truing apparatus adapted for use in a cylindrical grinding machine wherein a work head with a work spindle for support of a workpiece and a wheel head with a grinding wheel for grinding the workpiece are mounted on a bed for relative movement in a Z-axis direction parallel with the rotation axis of the work spindle and in an X-axis direction crossing the Z-axis direction, characterized in that the wheel truing apparatus comprises a rotary drive portion mounted on the work head or a member united therewith, and a wheel truing tool supported on the rotary drive portion for rotation therewith, the wheel truing tool being provided at its outer periphery with a truing portion for truing a grinding surface of the wheel brought into contact therewith, wherein the rotary drive portion is placed in a position adjacent to said work head in a tooling area defined by a stroke of the relative movements of said wheel head and said work head in the Z-axis direction and apart from said work spindle radially outward and is arranged in such a manner that the rotation axis line of said truing tool is oriented toward the rotation axis line of said grinding wheel in a condition where said truing portion is retained in contact with the grinding surface of said wheel, whereby the truing portion of said tool is brought into contact with the grinding surface of said wheel by relative movement of said wheel head to said work head for truing the grinding surface.

Truing apparatus of grinding wheel

In a vitrified bonded grinding wheel that is formed so that superabrasives formed of cubic boron nitride (CBN) grains or diamond grains are bonded and held with a vitrified binder, the vitrified binder is formed of oxide particles and amorphous glass, and the vitrified binder has no open pore that is in fluid communication with outside air.

Vitrified bonded grindstone

A grinding machine is provided with first and second grinding wheels selectively used in dependence on the steps of machining operations. The second grinding wheel is grooved so that at least one oblique groove vertically crosses a contact surface on which a grinding surface of the second grinding wheel contacts with a workpiece, and thus, is capable of releasing a dynamic pressure in coolant generated between the grinding surface and the workpiece since coolant supplied from over the contact surface flows out from both of the upper and lower sides of the contact surface through the at least one oblique groove. Since it does not occur that fluctuations in the dynamic pressure generated in coolant cause the distance between the second grinding wheel and the workpiece to be varied, the accuracy in grinding the workpiece with the second grinding wheel can be enhanced.

Grinding machine and grinding method

A tangential grinding resistance measuring method includes obtaining an abrasive grain section area which is at a predetermined infeed depth from the highest top surface of abrasive grains on a grinding wheel; calculating the tangent of a half vertex angle of a conical model for cutting edges of the abrasive grains which model takes the abrasive grain section area as its bottom surface and the predetermined depth as its height; setting grinding parameters; and calculating a tangential grinding resistance from the grinding parameters and the tangent.

Tangential grinding resistance measuring method and apparatus, and applications thereof to grinding condition decision and wheel life judgment

An abrasive grainincludes a crystal defect CD in its crystal structure CS. The crystal defect CD is formed by a laser irradiation.

Abrasive grain and grindstone

A grinding method of a rotating workpiece W having a cylindrical partand a pair of end facesat both sides of the cylindrical partuses a grinding wheelwhose grinding stone is narrower than a finishing width Sbetween the end faces. In a first grinding step, the grinding wheelis relatively moved to the cylindrical partin a direction crossing the rotational axis of the workpiece W and is shuttled along the rotational axis of the workpiece W at least one time between the finishing width Sof the end facesuntil the grinding wheelreaches the cylindrical part. And in a second grinding step, the grinding wheelis moved from one of the end facesto the opposite end faceon the cylindrical part, so as to finish the end facesto a predetermined width S

Grinding method and grinding machine

In a coolant supply method and apparatus for a grinding machine, when an end surface of a workpiece is ground with a grinding wheel end surface of a grinding wheel with coolant being supplied toward a grinding point, a first coolant flow is ejected toward a first position which is on the grinding wheel end surface on an upstream side of the grinding point, and intercepts an air layer rotating to follow the grinding wheel end surface. At the same time, a second coolant flow is ejected toward a second position which is on the grinding wheel end surface and which is closer to the grinding point than the first point, and clings onto the grinding wheel end surface at the second position where the follow air layer has been intercepted by the first coolant flow. Thus, the coolant of a sufficient volume can be supplied to the grinding point where the grinding wheel end surface grinds the end surface of the workpiece.

Coolant supply method and apparatus for grinding machine

In a grinding machine grinding a workpiece W by a grinding wheel G to supply coolant to one of a grinding point P or the workpiece W by way of a relative movement between the grinding wheel W rotatably supported on a wheel slideand the workpiece W supported by a work support device, air layerflowing on a circumferential surface Gc of said grinding wheel G by blowing hydraulic jettransversally from one side to the other side of the grinding wheel G along the circumferential surface Gc at an upper stream position of a rotational direction of the grinding wheel G from the grinding point P. Mist of coolant blown by the hydraulic jetthrough a recovering portmounted on a wheel guardcovering a part of the grinding wheel G.

It is one object of a grinding machine and a grinding fluid supply-nozzle therefor according to the present invention to supply grinding fluid to a moving grinding point reliably, even if the surfaces of a grinding wheel is abraded up. A wheel headadvances/retracts to a workpiece. A grinding wheel G is carried rotatably by the wheel headand grinds an eccentric portion W of the workpiece. A grinding fluid supply-nozzlesupplies grinding fluid to a moving grinding point K where the grinding wheel G contacts the eccentric portion W of the workpiece. The grinding fluid supply-nozzleis made from a curve portion, an openingand a straight portionbetween the curve portionand the opening. The grinding fluid supply-nozzlespouts the grinding fluid to a grinding fluid supply point Pc upstream the grinding points K and Ks, even in the case that the grinding wheel G has been abraded up. Besides, the angle between the tangent of the grinding fluid supply point Pc and the grinding fluid spouted from the grinding fluid supply-nozzleis smaller than a right angle.

Grinding machine and grinding fluid supply-nozzle therefor

The present invention supplies coolant to a grinding wheel surface and reliably guides the coolant to a grinding point on the grinding wheel surface, thereby significantly reducing the amount of coolant to be used. In a grinding method and device for supplying coolant while grinding a workpiece W with a rotating grinding wheel, a fluid nozzleis disposed upstream from a grinding pointon the circumferential surfaceof the grinding wheel. The fluid nozzleblows a jet of fluid across an air layer, which is a layer of flowing air dragged along the circumferential surfaceof the grinding wheel, from one lateral side of the air layerto the other lateral side thereof. A grinding fluid nozzlesupplies coolant to a region between the grinding pointand a cutoff positionat which the fluid jet from the fluid nozzlehas deflected the air flow from the air layer. The coolant supplied from the grinding fluid nozzlecontacts the grinding pointon the grinding surface

Grinding method and device for the same

In the grinding process, grinding fluid is supplied toward the grinding point where a workpiece is ground with a grinding wheel. At the same time, a fluid jet is ejected across the air flow above the grinding point in the rotational direction of the grinding wheel. As a result, the air layers on both lateral sides of the grinding wheel are turned not to head for the grinding point above the same, whereby the grinding fluid is reliably led to the grinding point without being obstructed by the air layers following both lateral sides of the grinding wheel.

Growing community of inventors

Hoi-gun, Japan

Hiroshi Morita