Kabushiki Kaisha Toyota Jidoshokki

Denso Corporation

Masahiro Inagaki

Shinya Yamamoto

Yuya Izawa

Makoto Yoshikawa

Kazuhide Kawai

Katsunori Akimoto

Kazutoyo Osuka

Jyunichi Wada

Yoshitaka Sato

Masahiko Aoyama

Masafuyu Sano

Koji Tsunenaga

Hajime Kasai

Takashi Tauchi

Ryosuke Koshizaka

Kaneo Buma

Hidetoshi Nakashima

Shigeya Abe

Kengo Osawa

Kentaro Ishihara

An ignition coil includes a primary coil, a secondary coil, a primary bobbin, a secondary bobbin, a center core, and a mold resin. The center core has a pair of collar portions protruding from a main body of the center core respectively to opposite sides in a protruding direction. The primary bobbin has a collar portion at least partially sandwiched between the collar portions of the center core and the secondary bobbin in a coil axial direction. The collar portion of the primary bobbin includes an overlapping portion that overlaps the collar portions of the center core in the coil axial direction and is bonded to the collar portions. The primary bobbin is formed of a thermoplastic resin and dispersed-phase particles dispersed in the thermoplastic resin. In the overlapping portion of the primary bobbin, there is formed a specific separating layer that separates adjacent layers in the coil axial direction.

Ignition coil for internal combustion engine

A screw rotor is for use in a screw pump that pumps fluid by rotation of a pair of screw rotors engaged with each other in a rotor housing. The screw rotor includes a multiple-thread portion for pump suction side and a single-thread portion for pump discharge side. The screw rotor is formed so that the tooth profile of the multiple-thread portion is connected to the tooth profile of the single-thread portion through a boundary plane that is perpendicular to the rotation axis of the screw rotor. The first curved portion coincides with the third curved portion in the boundary plane.

Screw rotor

A housing of a Roots pump is configured by joining a lower housing member and an upper housing member that are separable from each other. With the upper and lower housing members joined together, an upper accommodating portion and a lower accommodating portion form a front bearing accommodating portion and a rear bearing accommodating portion, which accommodate whole bearings, respectively. The Roots pump further includes bearing holders attached to the bearings and fixed to the lower housing member so that the bearings are received in the lower accommodating portion in a positioned state.

Root pump

A housing () of a Roots pump () supports a drive shaft () and a driven shaft () with radial bearings () so as to be rotatable. The housing () is formed by joining an upper housing member () to a lower housing member (). The lower housing member () has lower bearing support portions (), and the upper housing member () has upper bearing support portions (). Opening edges () of each lower bearing support portion () are positioned above the centers (P) of the bearings (). An opening width (T) of each lower bearing support portion () is smaller than the diameter (D) of the bearings (). This structure suppresses the bearings () from being separated from the lower housing member () during an assembling operation of the fluid machine.

Fluid machine with divided housing

A cross section of a tooth profile of a first screw rotor () perpendicular to the rotor axis includes a tooth top arc (AB), a tooth bottom arc (CD), a first curve (AC), and a second curve (BD). The first curve (AC) is a first trochoidal curve that connects a first end (A) of the tooth top arc (AB) to a second end (C) of the tooth bottom arc (CD). The second curve (BD) connects the second end (B) of the tooth top arc (AB) to the first end (D) of the tooth bottom arc (CD). The second curve (BD) is a composite curve formed by an involute curve (BE) and a second trochoidal curve (ED), which extend continuously from each other at a first intersection point (E). A screw pump () thus suppresses leakage of fluid with improved performance.

Screw pump and screw rotor

An ignition coil includes primary and secondary coils, center and outer cores, and an ion current detector for transmitting an ion current detection output. The center core has an axial upper end defining a center core upper end surface. The outer core has an axial upper end defining an outer core upper end surface. The center core upper end surface axially protrudes upwardly relative to the outer core upper end surface. The center core upper end surface is located at a stagger distance axially from the outer core upper end surface. The stagger distance is defined such that a detection period for residual magnetic noise in the ion current detection output falls within a system requirement period of a control unit.

Ignition coil and ignition coil system having the same

A screw pump includes a housing and a pair of intermeshing screw rotors. An end face of the rotor adjacent to an inlet port of the housing is provided with an inlet opening. Each rotor has a first portion whose lead angle changes. The first portions and the housing cooperate to form an inlet space. During rotation of the rotors, communication between the inlet space and the inlet port is blocked by the first portions and the housing thereby to form a closed pump space adjacent to the inlet space. Volume of the pump space is set smaller than the maximum volume of the inlet space. A closure member is provided which covers at least a part of the inlet openings. The closure member closes the inlet space when the volume of the inlet space exceeds that of the pump space.

Screw pump with increased volume of fluid to be transferred

A screw pump includes a housing and a pair of intermeshing screw rotors. The housing has an inlet port and an outlet port. Each rotor has a first portion whose lead angle decreases. The first portion and the housing form an inlet space and a pump space. Winding angle of the first portion has a first region and a second region. The first region is located in a predetermined range from the end on the first portion adjacent to the inlet port toward the outlet port. The second region is located adjacent to the first region. Reduction rate of the lead angle of the first portion in the first region is set smaller than that in the second region. The maximum lead angle of the first portion is set smaller than a lead angle which decreases at a constant rate in the first region and the second region.

Screw pump with improved efficiency of drawing fluid

A vacuum pump includes a housing assembly having an oil-reservoir chamber in which a lubricating oil is stored; a pair of screw rotors disposed in the housing assembly and engaged with each other; a pair of rotary shafts connected to the rotors, respectively; a plurality of bearings supporting each of the rotary shafts and having an opening; an oil-feed pump for feeding the lubricating oil from the oil-reservoir chamber to the bearing; an oil-circulation passage provided for circulating the lubricating oil from the oil-feed pump to the oil-reservoir chamber through the bearing; a cover provided at the opening of the bearing to close the opening of the bearing with a clearance remained, the cover permitting the lubricating oil to enter the bearing through the clearance; and an oil-escape passage provided adjacent to the bearing for returning to the oil-reservoir chamber the lubricating oil not entering the bearing.

Vacuum pump with improved oil lubrication

In a stick coil, there is disclosed an ignition coil for an internal combustion engine which can prevent a crack (a collar leak) from being generated due to a thermal stress. In this ignition coil, the structure is made such that a size (L) of a portion which is in parallel to an axial direction of a primary spool ( ) in a projection portion ( ) is larger than a size (T) of a portion which is in parallel to an orthogonal direction to the axial direction of the primary spool ( ). Accordingly, a frontal projected area of the projection portion ( ) as seen from a flowing direction of a resin becomes small, a resin flow is hard to get out of order at a time when the resin flows through a portion corresponding to the projection portion ( ) at the forming time, and a convoluted void and a weld are hard to be generated. Accordingly, since it is possible to prevent a mechanical strength in a root portion of the projection portion ( ) from being reduced, it is possible to previously prevent a crack from being generated in the root portion of the projection portion (the collar portion) ( ) due to a thermal stress so as to reduce an insulating property.

Growing community of inventors

Kariya, Japan

Masahiro Inagaki