EP0073457A2

EP0073457A2 - Ignition distributor with induction detector

Info

Publication number: EP0073457A2
Application number: EP82107756A
Authority: EP
Inventors: Marian Fabrycy; Jan Winiecki; Tadeusz Strzalkowski; Andrzej Jakubowski
Original assignee: Przemyslowy Instytut Automatyki i Pomiarow "MERA-PIAP"
Current assignee: Przemyslowy Instytut Automatyki i Pomiarow "MERA-PIAP"
Priority date: 1981-08-27
Filing date: 1982-08-24
Publication date: 1983-03-09
Also published as: HUT34585A; EP0073457A3; DD202749A5

Abstract

The ignition distributor with induction detector is appropriate for internal combustion engines with electronic ignition and mechanical spark-advance controls and is characterized in that the magnetic circuit is closed over a magnet (6) connected immovably with the body (1), a magnet pole shoe (8), a sleeve (12), an oscillating armature (13) with claw-type pole shoes (14), a variable gap (24) between the internal surface of a rotational armature (17) and the external surface of the claw-type pole shoe (14) of the oscillating armature (13), the rotational armature (17) and a permanent gap (23) between the external surface of the rotational armature (17) and the internal surface of the magnet (6). The sleeve (12) is disposed inside the coil and is coupled with a vacuum spark-advance control (16).

The rotational armature (17) is fitted in the body (1) made of a non-magnetic material, connected with the centrifugal governor (4).

Description

This invention relates to an ignition distributor with an induction detector, appropriate for internal combustion engines with electronic ignition and mechanical spark-advance control.
From the laid open specification DE 2450752 there is known an ignition distributor with induction detector, having a single-stage differential magnetic system consisting of a magnet with an external pole shoe provided with claw-type protrusions co-operating with claw-type protrusions of the rotational armature. The magnet, the pole shoe with claw-type protrusions and the magnet stator are coupled with a vacuum spark-advance control, and perform a swinging motion, increasing the mass of the control system.
The single-stage differential system of the magnetic circuit, as plays occur in the mechanical system of the distributor, is inadequate for removing the effect of said plays upon the stability of the amplitude and the signal waveform, what causes a necessity to restrict the manufacturing tolerances, and in the result it increases the production costs.
In the ignition distributor according to the invention, consisting of a body, a centrifugal governor, a vacuum spark-advance control, as well as of a magnet and a coil, the magnetic circuit gets closed by the magnet connected immovably with the body, the magnet pole shoe, a sleeve and an oscillating armature of the internal circuit, and over the gap between the claw-type pole shoe of the oscillating armature and the pole shoe of the rotational armature, over the pole shoe of the rotational armature, and the gap between the rotational armature and the magnet.
The internal magnetic circuit is formed by the sleeve disposed inside the coil, an oscillating armature and a plate coupling the internal circuit with the vacuum spark-advance control.
The internal circuit is born in the distributor body or directly in the coil.
The rotational armature employed in the distributor according to the invention has the form of a ring with protrusions from the internal side, constituting the pole shoes of the rotational armature. It consists of two or more identical ring sectors with ends bent towards the inner, preferably welded together into a single entirety and pressed down in the body made of non-magnetic material. The bent and welded ends of the ring sectors form the pole shoes of the rotational armature.
The subject of the invention is shown by way of an exemplary embodiment, with reference to the accompanying drawing, wherein:

Fig. 1 is a vertical sectional view of the distributor according to the invention,
Fig. 2 is a top view of relative positioning of the magnet, the rotational armature, and the oscillating armature, and
Fig. 3 is a fragmentary view of the distributor magnet with an additional pole shoe.

The ignition distributor according to the invention consists of a body 1 having a hole in its axis of symmetry, wherein a sleeve 2 is disposed, bearing a driving shaft 3 connected permanently with a known centrifugal governor 4. To the body 1, by means of for instance at least two screws 5, is attached a ring-shaped magnet 6 with a clamping ring 7 and a disk pole shoe 8·of the magnet, wherein mounting sleeves 9 are disposed. Co-axially with the magnet 6 is disposed a coil 10 with a carcass 11, the outer diameter of the lower base whereof equals to the inner diameter of the magnet 6.
A sleeve 12 with an oscillating armature 13 fitted thereon from above and provided with claw-type pole shoes 14, and from the bottom a coupling plate 15 form the internal magnetic circuit. The internal circuit is disposed inside the coil 10 and is born in the body 1 by the bearing sleeve 2. The internal circuit is coupled with a known spark-advance control 16 by means of the coupling plate 15, and performs an oscillating motion.
Between the magnet 6 and the claw-type pole shoes 14 of the oscillating armature 13 a rotational armature 17 is disposed, having the form of a ring consisting of two half-rings having the ends bent towards inside and welded with each other into a single entirety. Said ends form the pole shoes 18 of the rotational armature 17. The rotational armature 17 is pressed into a body 19 made of a non-magnetic material, connected with a known centrifugal governor 4 with which the distributor rotor arm 20 is coupled.
By the disposition of the rotational armature 17 within the space between the magnet 6 and the oscillating armature 13 a permanent gap 23 between the external surface of the rotational armature 17 and the internal surface of the magnet 6 and a variable gap 24 between the internal.surface of the rotational armature 17 and external surface of the claw-type pole shoe of the oscillating armature 13 are.formed.
The entire gear is closed from the top.by a dome 21.
In each embodiment the number of claw-type pole-shoes 14 of the oscillating armature 13 equals to that of the pole shoes 18 of the rotational armature 17. Said number can, however, assume various values for various embodiments, in dependence on the number of cylinders in the engine whereto the given ignition distributor is designed.
In an embodiment other than that shown in Fig. 1, the internal circuit of the distributor, consisting of the sleeve 12, the oscillating armature 13, and the coupling plate 15 can be born directly in the carcass 11 of the coil 10. The rotational armature 17 can be made as a monolithic element. In case of employing of a ferritic magnet in the distributor, the magnet 6 should be equipped with an additional pole shoe 22 having the shape of a cylinder. In this case, the permanent gap 23 will be formed between the inside surface of the additional pole shoe 22 and the outside surface of the rotational armature 17.
The magnetic circuit of the distributor gets closed over the magnet 6, the magnet pole shoe 8, the sleeve 12, the oscillating armature 13 and its claw-type pole shoe 14, the variable gap 24, the rotational armature 17 and the permanent gap 23. At rotation of the driving shaft 3 it follows a rotation of the centrifugal governor 4, and together therewith - of the body 19 with the rotational armature 17. The positioning of the pole shoe 18 of the rotational armature 17 opposite to the claw-type pole shoe 14 of the oscillating armature 13 causes a variation of the value of magnetic flux in result of variation of the variable gap 24 value. The variation of the magnetic flux value causes a generation of a signal in the coil 10, being transmitted to the electronic . system.

Claims

1. An ignition distributor with an induction detector, appropriate for internal combustion engines with electronic ignition and.with mechanical spark-advance controls, consisting of a body (1) wherein a driving shaft (3) is born, of a centrifugal governor (4), a vacuum spark-advance control, as well as of a magnet (6), and a coil (10), characterized in that the magnetic circuit consists of the magnet (6) connected immovably to the body (1), a magnet pole shoe (8), a sleeve (12), and an oscillating armature (13) with claw-type pole shoes (14) of the internal circuit, of a variable gap (24) between the inner surface of a rotational armature (17) and the outer surface of a claw-type pole shoe (14) of the oscillating armature (13), the rotational armature (17), and the permanent gap (23) between the external surface of the rotational armature (17) and the internal surface of the magnet (6), whereby the sleeve (12) of the inner circuit is disposed inside the coil (10)and coupled with the vacuum spark-advance governor (16), and the rotational armature (17) is fitted in a body (19) made of non-magnetic material and connected to the centrifugal governor (4).

2. A distributor as defined in claim 1, characterized in that the internal circuit consisting of the sleeve (12), the oscillating armature (13) and a coupling plate (15) is born in the body (1).

3. A distributor as defined in claim 1, characterized in that the internal circuit consisting of the sleeve (12), the oscillating armature (13), and the coupling plate (15) is born in the coil (10).

4. A distributor as defined in claim 1, characterized in that the rotating armature (17) has the form of a ring consisting of two or more identical ring sec- . tors having the ends bent towards the inside and preferably welded to each other to form a single entirety, said ends forming pole shoes (18).

5. A distributor as defined in claim 1, characterized in that the magnet (6) is on its upper surface provided with an additional pole shoe (22).

6. A distributor as defined in claim 5, characterized in that the permanent gap (23) is formed between the external surface of the rotational armature (17) and the internal surface of the additional pole shoe (22) of the magnet (6).