Eureka AIR delivers breakthrough ideas for toughest innovation challenges, trusted by R&D personnel around the world.

Glow plug

a technology of glow plugs and o-rings, which is applied in the direction of incandescent ignition, combustion process, lighting and heating apparatus, etc., can solve the problems of difficulty in providing a space for accepting deformation of compressed o-rings, failure to ensure gastightness, and breakage of o-rings

Inactive Publication Date: 2013-09-26
NGK SPARK PLUG CO LTD
View PDF2 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The patent relates to a glow plug used in automobiles and the invention is a new design for the contact member that reduces friction and prevents twisting of the O-ring during assembly. The contact member is designed to have a contact area with the shoulder portion of the glow plug that is small to prevent the contact member from being caught and dragged inward. This results in a more stable attachment of the contact member to the glow plug and reduces the risk of failure during use.

Problems solved by technology

However, in the configuration in which the three contact surfaces of the inner circumferential surface, the center shaft, and the insulation member surround the O-ring, difficulty is encountered in providing a space for accepting deformation of a compressed O-ring.
Accordingly, the O-ring is deformed in such a manner as to enter a narrow gap between the contact surfaces; thus, internal stress in a deformed portion of the O-ring increases, potentially resulting in breakage of the O-ring.
Accordingly, the O-ring fails to maintain sufficient close contact with the contact surfaces; thus, a clearance is formed therebetween, potentially resulting in a failure to ensure gastightness.
In the process of assembling a glow plug, when the O-ring is to be disposed in a narrow gap between the center shaft and the inner circumferential surface of the axial bore, there has been involved the risk of twist of the O-ring along the circumferential direction.
Joint use of an axially long tube-like vibration insulating rubber or the like encounters difficulty in disposition between the center shaft and the inner circumferential surface of the axial bore and increases cost.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Glow plug
  • Glow plug
  • Glow plug

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0024]A glow plug according to an embodiment of the present invention will next be described with reference to the drawings. The entire structure of a glow plug 1 is described, by way of example, with reference to FIGS. 1 and 2. The drawings referred to herein are used for explaining technical features which the present invention can employ, and the configuration, etc., of the glow plug appearing in the drawings are given by way of illustration and not of limitation. In the following description, the axis of a metallic shell 4 is referred to as the axis O, and the axis O serves as reference in describing the positional relationship, orientations, and directions of those component members of the glow plug 1 which are attached to the metallic shell 4. With respect to the extending direction of the axis O (hereinafter, may be referred to as “the direction of the axis O”), a side on which a ceramic heater 2 is disposed (the lower side in FIG. 1) is referred to as the forward side of the...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

A glow plug (1) including a heater (2), a metallic shell (4) assuming the form of a tube having an axial bore, a center shaft (3) and a contact member (7). The contact member (7) is configured such that a contour (70) of a cross section (75) includes a second contour segment (71) in the form of a straight line, a first contour segment (72) in the form of a curve swelling radially, and third contour segments (73) in the form of curves connecting the second contour segment (71) and the first contour segment (72).

Description

TECHNICAL FIELD[0001]The present invention relates to a glow plug used for assisting in start-up of a diesel engine.BACKGROUND ART[0002]A glow plug used for assisting in start-up of a diesel engine is such that a heater which has a heat-generating resistor at its forward end portion is held directly or indirectly at a forward end portion of a tubular metallic shell having an axial bore. A rodlike center shaft is inserted into the axial bore of the metallic shell and disposed in a condition electrically insulated from the metallic shell. One end portion of the center shaft is connected to a rear end portion of the heater, and the other end portion projects from the rear end of the metallic shell. Two electrodes led from the heater are electrically connected to the metallic shell and the center shaft, respectively.[0003]In the thus-configured glow plug, in order to ensure gastightness through the axial bore of the metallic shell, an O-ring is disposed between the center shaft and the ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(United States)
IPC IPC(8): F23Q7/00
CPCF23Q7/001
Inventor ITO, KATSUTERUSUZUKI, HIROYUKIHATANO, GAKU
Owner NGK SPARK PLUG CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Eureka Blog
Learn More
PatSnap group products