GB2074794A

GB2074794A - Improvements relating to the mounting of electric starter motors

Info

Publication number: GB2074794A
Application number: GB8105800A
Authority: GB
Original assignee: Societe de Paris et du Rhone SA
Current assignee: Societe de Paris et du Rhone SA
Priority date: 1980-02-26
Filing date: 1981-02-24
Publication date: 1981-11-04
Also published as: ES268980U; DE3105772C2; FR2476753B1; JPS56136151A; ES268980Y; DE3105772A1; GB2074794B; FR2476753A1

Abstract

An electric starter for an engine is supported by a mounting member 2 having an upper hollow boss 7 for the solenoid and a sleeve 6 for the yoke of the starter motor, a passage 9 being provided for the actuating lever of the drive pinion assembly and the end of the passage 9 being closed by a mounting member 3 in the form of a metal plate holding a seal 4. A lug 3d on the plate 3 enters a slot 1b in the yoke 1, thus angularly positioning the yoke. <IMAGE>

Description

SPECIFICATION Improvements relating to the mounting of electric starter motors The present invention relates to improvements made to the system of positioning the yoke of the electric motor of a starter for an engine relative to the holding means by which it is attached to the engine.

This holding means is used for centering the yoke of the electric motor and determining its angular orientation. In addition, it supports the solenoid used to actuate the drive pinion assembly of the starter with the aid of a lever.

The outlet of the passage in which the lever is situated is closed by a seal. In order to avoid any creep in this seal under the various stresses to which it is subjected, it has already been proposed to support it by means of a mounting member in the form of a small plate held in the holding means.

The solutions usually adopted for the angular positioning of the yoke of the electric motor of a starter for an internal combustion engine relative to the holding means attaching it to this engine make use of a spur protruding from the yoke and fitting into a slot in the holding means. This solution is unsatisfactory because such a spur is of small section, so that the angular forces to which the yoke is subjected may give rise to the deformation of the slot in the holding means, particularly as the latter is made of light alloy. The yoke is thus frequently held insecurely.

The improvements forming the object of the present invention seek to overcome this disadvantage. According to the invention, the mounting member for the seal takes the form of a metal plate provided with means for the angular positioning of the yoke of the electric motor relative to the holding means attaching the starter to the engine.

In a preferred embodiment the plate is provided with a lug projecting obliquely and engaging in a slot in the yoke. The fact that this lug is oblique enables it to be given a maximum length, so that the mounting of the yoke is facilitated while its angular retention is 'satisfactory.

The accompanying drawings, given by way of example, show embodiments of the invention.

Figure 1 is an exploded view of the principal component parts of an electric starter for an internal combustion engine, with the exception of the body of the solenoid and parts of no interest to the invention; Figure 2 is an exploded view in perspective illustrating the fitting of a plate forming part of the invention; Figure 3 is a cross-sectional view on a larger scale, taken in a horizontal plane through the plate; Figure 4 is a longitudinal section taken at the same point; and Figure 5 is a view of the holding means associated with a plate constructed in accordance with a modified embodiment.

In Figure 1 are shown the yoke 1 of the electric motor of a starter for an internal combustion engine, the holding means 2 attaching it to the engine, and also a folded sheet metal plate 3, the plate 3 supporting a seal 4.

The holding means 2 is generally made of cast aluminium and it comprises the nose 5 of the starter, a sleeve 6 effecting the centering of the yoke 1, and a hollow boss 7 supporting the body of a solenoid actuating the engaging lever of the drive pinion assembly of the starter. It can be seen that the sleeve 6 and the hollow boss 7 are joined by a connecting member 8.

Figure 2 shows on a larger scale the joining of the hollow boss 7 and the sleeve 6. It will be seen that the connecting member 8 is composed of two longitudinal parts 8a, 8b, which between them form a passage 9 in which is situated the usual actuating lever of the drive pinion assembly, not shown.

The plate 3 is composed of a U-shaped gutter 3a, the ends of whose arms are extended by flaps 3b,3c lying parallel to the web of the gutter and provided with rounded outer edges. In each of the two parts 8a,8b of the connecting member 8 is formed a recess matching the shape of the plate, or more accurately the shape of its flap 3b,3c. The width of the gutter 3a corresponds to that of the passage 9. In Figure 3 are shown the recess 8d,8e of the parts 8a,8b respectively and also the position of the plate in these recesses, the depth of which corresponds to that of the flaps, so that the upper face of the flaps is flush with the end face of the connecting member 8.

The bottom edge of the plate 3 carries a lug 3d directed obliquely towards the outside of the holding means 2. The protruding fitting rim la of the yoke, which engages inside the sleeve 6, is provided with a slot 1 b, the width of which is equal - allowing for clearance - to that of the lug 3d of the plate 3.

The seal 4 comprises a front portion 4a with a rounded lower surface, the diameter of which corresponds to the inside diameter of the sleeve 6, and a rear portion 4b whose shape matches that of the gutter 3a, so as to engage therein, while it also has two side legs 4c,4d adapted to bear against the flaps 3b,3c of the plate 3. The latter therefore presses the rear portion 4b of the seal 4 against the shoulder ic formed on the yoke 1 by its fitting rim 1 a, as shown more particularly in Figure 4.

In Figure 4 it can be seen that the fact that the lug 3d of the plate 3 is oblique enables its length to be increased and therefore enables it to be introduced easily into the slot 1 b in the yoke 1, so that the mounting of the yoke is facilitated. Furthermore, the two lateral edges of this lug are of maximum length, so that their support surfaces in relation to the side faces of the slot are as large as possible, thus improving the centering properties. Moreover, since this plate is of steel, there is no risk of damage either to the lug 3d or to the slot 1 b, since the yoke is likewise of steel.

A particularly economical assembly has thus been achieved, which in addition makes it possible to obtain excellent positioning of the yoke relative to the holding means attaching the starter to the engine.

The shapes of the recesses 8d, 8e and the corresponding shapes of the flaps 3b, 3c of the plate could obviously be different, provided however that this plate is held radially in relation to the centre of the sleeve 6. The flaps in question and the corresponding recesses could for example have the shape of the transverse arm of a cross. Furthermore, it would be possible to bend out of the plate 3 a beak 3e (Figure 4) adapted to penetrate into a corresponding slot formed in the seal 4, so as to join these two parts together and thus to facilitate their mounting.

It should moreover be understood that the above description has been given only by way of example, and that it does not in any way limit the scope of the invention. In particular, as an alternative the plate 3 could be flat (as shown at 3' in Figure 5) and its centering achieved only by means of its side edges 3'f, 3'9 engaging in corresponding recesses 8'd, 8'e of the connecting member 8.

Claims

1. An electric starter for an an engine, of the type comprising an electric motor and means for controlling an actuating lever for the drive pinion assembly, a seal held against a mounting member closing the outlet of the passage for the lever, characterised in that the mounting member is in the form of a metal plate provided with means for the angular positioning of the yoke of the electric motor relative to the holding means attaching the starter to the engine.

2. A starter according to Claim 1, wherein the plate (3) is provided with axial retention means (3a, 3b, 3c).

3. A starter according to Claim 2, wherein the plate (3) has in plan profile a barrel shape, and in that it is engaged in a depression (8d, 8e) of compiementary shape formed in the holding means of the starter.

4. A starter according to any one of the preceding claims, wherein the angular positioning means for the yoke consist of a lug (3d) which projects obliquely and which engages in a slot (1 b) in the yoke (1).

5. A starter according to any one of the preceding claims, wherein the plate (3) is provided with means (3e), known per se, for retaining the seal (4).

6. A starter according to Claim 5, characterised in that the plate (3) is provided with a beak (3e) which engages in a socket in the seal (4).

7. An electric starter for an engine substantially as shown in the accompanying drawings and described herein with reference thereto.