ISO 7876-3:1993

Fuel injection equipment - Vocabulary - Part 3: Unit injectors

Establishes a vocabulary and definitions relating to unit injectors for compression-ignition (diesel) engines.

Équipement d'injection de combustible — Vocabulaire — Partie 3: Injecteurs-pompes

La présente partie de l'ISO 7876 établit un vocabulaire et des définitions relatifs aux injecteurs-pompes pour moteurs à allumage par compression (diesel) et à leurs composants. Elle est complémentaire de l'ISO 2710.Les définitions contenues dans la présente partie de l'ISO 7876 sont spécifiques aux injecteurs-pompes. Les autres aspects d'ordre général relatif aux porte-injecteurs complets de combustible sont définis dans l'ISO 7876-2.

General Information

• Status: Published
• Publication Date: 14-Jul-1993
• ICS: 01.040.43 - Road vehicle engineering (Vocabularies)
• ICS: 43.060.40 - Fuel systems
• Technical Committee: ISO/TC 22/SC 34 - Propulsion, powertrain and powertrain fluids
• Drafting Committee: ISO/TC 22/SC 34 - Propulsion, powertrain and powertrain fluids
• Current Stage: 9060 - Close of review
• Completion Date: 02-Sep-2030

Overview

ISO 7876-3:1993 is an international standard developed by the International Organization for Standardization (ISO) that establishes a precise vocabulary and definitions related specifically to unit injectors used in compression-ignition (diesel) engines. Part 3 of the ISO 7876 series, this standard complements the other parts which address fuel injection pumps, fuel injectors, and high-pressure pipes and end connections.

Unit injectors are critical components in diesel engines, combining the functions of a single-cylinder pump and an injector in one compact assembly. This standard aims to unify the terminology surrounding these complex assemblies to support clear communication, design, manufacturing, testing, and maintenance within the automotive and engine industries.

Key Topics

• Unit Injector Definition:
  ISO 7876-3 defines a unit injector as an assembly that integrates the features of a single-cylinder pump and an injector, enabling metered fuel injection at high pressure directly into the combustion chamber. The standard specifies that unit injectors include three principal functions: actuation (energy input), timing control (advance control), and fuel metering (dosage control).

• Component Descriptions:
  The standard details components specific to unit injectors such as:

  • Tappet (Follower) Assembly: Transmits linear motion from external driving parts to the plunger.
  • Tappet Head, Thrust Pad, Tappet Body, and Guide: Breaks down the tappet’s mechanical features.
  • Return Spring: Maintains contact and resets the tappet position.
  • Unit Injector Body: Encloses the pumping elements.
  • Nozzle Spring and Housing: Controls the needle valve operation during injection.
  • Metering Device: The integral part that determines fuel quantity injected.

• Unique Vocabulary:
  This standard provides distinct definitions that are exclusive to unit injectors, differentiating from broader fuel injection terminology addressed in related parts ISO 7876-1 and ISO 7876-2.

• Normative References:
  It references related standards such as ISO 7876-1:1990 for fuel injection pumps and ISO 7876-2:1991 for fuel injectors, ensuring consistency across the vocabulary series.

Applications

• Automotive Engineering:
  Facilitates uniform understanding among automotive manufacturers, suppliers, and engineers designing and operating diesel engine fuel systems relying on unit injectors.

• Technical Documentation and Training:
  Provides a standardized language for manuals, training materials, and technical communications critical for maintenance and troubleshooting of unit injector systems.

• Quality Assurance and Testing:
  Supports clear specifications and testing protocols by defining exact parts and functions, improving quality control across production and service.

• Research and Development:
  Assists R&D teams in accurately discussing features and innovations involving unit injectors, particularly where mechanical, hydraulic, electrical, or electronic actuation mechanisms are involved.

• Global Trade and Compliance:
  Ensures that stakeholders across different countries and sectors use consistent terminology, aiding regulatory compliance and international collaboration in engine manufacturing.

Related Standards

• ISO 7876-1:1990 – Fuel Injection Pumps:
  Offers vocabulary for various fuel injection pump components and functions.

• ISO 7876-2:1991 – Fuel Injectors:
  Defines terms related to complete fuel injector assemblies distinct from unit injectors.

• ISO 2710:1978 – Reciprocating Internal Combustion Engines Vocabulary:
  Supplies a foundational language framework relevant to internal combustion engine components and terminology.

• Additional ISO 7876 Series Parts:
  Standardizes vocabulary for high-pressure pipes and end connections, enhancing integration with the unit injector terminology.

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Keywords: ISO 7876-3, unit injectors, fuel injection equipment, diesel engines, compression-ignition engine, injector vocabulary, fuel metering, tappet assembly, nozzle spring, fuel injection components, diesel engine standards, automotive engine parts, international standards for fuel injection

Standards Content (Sample)

INTERNATIONAL
ISO
STANDARD
7876-3
First edition
NORME Premiere Edition
1993-07-15
INTERNATIONALE
Fuel injection equipment - Vocabulary -
Part 3:
Unit injectors
Equipement d’injection de combustible -
Vocabulaire -
Partie 3:
Injecteurs-pompes
Reference number
Numhro de rkfhrence
ISO 7876=3:1993(E/F)
Contents
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 Scope
2 Normative references .
................................................................... 2
3 Main definition
...................................................................... 2
4 Components
.................................................................... 3
5 General terms
Annex A: Bibliography .
Alphabetical indexes
English . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
French . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*.
Sommaire
.......................................................... 1
1 Domaine d’application
.......................................................... 1
2 Refkences normatives
............................................................. 2
3 Definition principale
4 Composants .
5 Termes gkn&aux .
Annexe A: Bibliographie .
Index alphabetiques
Anglais . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Francais . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*.
0 ISO 1993
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including photocopying and microfilm, without
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Permission in writing from the publisher./Droits de reproduction reserves. Aucune Partie de
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6crit de Mditeur.
International Organization for Standardization
Case postale 56 l CH-121 1 Geneve 20 l Switzerland
Printed in Switzerland/lmprime en Suisse
ii
ISO 7876=3:1993(E/F)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation
of national Standards bodies (ISO member bodies). The work of preparing lnter-
national Standards is normally carried out through ISO technical committees.
Esch member body interested in a subject for which a technical committee has
been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also
take part in the work. ISO collaborates closely with the International Electro-
technical Commission (IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are circulated
to the member bodies for voting. Publication as an International Standard
requires approval by at least 75 % of the member bodies casting a vote.
International Standard ISO 78763 was prepared by Technical Committee
lSO/rC 22, Road vehicles, Sub-Committee SC 7, Injection eguipment and filters
for use on road vehicles.
ISO 7876 consists of the following Parts, under the general title Fuel injection
equipment - Vocabulary :
- Part 1: Fuel injection Pumps
- Part 2: Fuel injectors
- Part 3: Unit injectors
- Part 4: High-pressure pipes and end connections
Annex A of this part of ISO 7876 is for information only.

ISO 7876=3:1993(E/F)
Avant-propos
L’ISO (Organisation internationale de normalisation) est une federation mondiale
d’organismes nationaux de normalisation (comites membres de I’ISO). L’elabo-
ration des Normes internationales est en general confiee aux comites techniques
de I’ISO. Chaque comite membre interesse par une etude a Ie droit de faire Partie
du comite technique cr& a cet effet. Les organisations internationales, gou-
vernementales et non gouvernementales, en liaison avec I’ISO participent
egalement aux travaux. L’ISO collabore etroitement avec Ia Commission electro-
technique internationale (GEI) en ce qui concerne Ia normalisation electrotech-
nique.
Les projets de Normes internationales adoptes par les comites techniques sont
soumis aux comites membres pour vote. Leur publication comme Normes inter-
nationales requiert I’approbation de 75 % au moins des comitks membres
votants.
La Norme internationale ISO 7876-3 a etc elaboree par Ie comite technique
lSO/rC 22, Whicules routiers, sous-comite SC 7, Equipements d’injection et
filtres pour application aux v6hicules routiers.
L’ISO 7876 comprend les Parties suivantes, presentees sous Ie titre general
Equipement d’injection de combustible - Vocabulaire :
- Partie 1: Pompes d’injection de combustible
- Partie 2: Porte-injecteurs de combustible complets
- Partie 3: Injecteurs-pompes
- Partie 4: Tuyauteries et raccords haute Pression
L’annexe A de Ia presente Partie de I’ISO 7876 est donnee uniquement a titre
d’information.
INTERNATIONAL STANDARD
ISO 7876=3:1993(E/F)
NORME INTERNATIONALE
Equipement d’injection de
Fuel injection equipment -
combustible -
Vocabulary -
Vocabulaire -
Partie 3:
Part 3:
Injecteurs-pompes
Unit injectors
1 Domaine d’application
1 Scope
La presente Partie de I’ISO 7876 etablit un vocabulaire et
This part of ISO 7876 establishes a vocabulary and defi-
des definitions relatifs aux injecteurs-pompes pour mo-
nitions relating to unit injectors for compression-ignition
teurs a allumage par compression (diesel) et a leurs com-
(diesel) engines, and their components. lt is complemen-
posants. Elle est complementaire de I’ISO 2710r1!
tat-y to ISO 2710!
Les definitions contenues dans Ia presente Partie de
Definitions in this part of ISO 7876 are unique to unit
I’ISO 7876 sont specifiques aux injecteurs-pompes. Les
injectors; other aspects more general to fuel injectors may
autres aspects d’ordre general relatif aux porte-injecteurs
be found in ISO 7876-2.
complets de combustible sont definis dans I’ISO 78762.
2 Rhfbrences normatives
2 Normative references
Les normes suivantes contiennent des dispositions qui,
The following Standards contain provisions which,
par Suite de Ia reference qui en est faite, constituent des
through reference in this text, constitute provisions of this
dispositions valables pour Ia presente Partie de I’ISO 7876.
International Standard. At the time of publication, the
Au moment de Ia publication, les editions indiquees
editions indicated were valid. All Standards are subject to
etaient en vigueur. Toute norme est sujette a revision et
revision, and Parties to agreements based on this Inter-
les Parties prenantes des accords fondes sur Ia presente
national Standard are encouraged to investigate the
Partie de I’ISO 7876 sont invitees a rechercher Ia possibi-
possibility of applying the most recent editions of
lite d’appliquer les editions les plus recentes des normes
the Standards indicated below. Members of IEC and
indiquees ci-apres. Les membres de Ia CEI et de I’ISO
ISO maintain registers of currently valid International
possedent Ie registre des Normes internationales en
Standards.
vigueur a un moment donne.
ISO 7876-1:1990, Fuel injection equipment - Vo
...