GB2355295A

GB2355295A - Impeller to shaft fixing

Info

Publication number: GB2355295A
Application number: GB0025034A
Authority: GB
Inventors: Valentino Tenco
Original assignee: Gate SRL
Current assignee: Gate SRL
Priority date: 1999-10-14
Filing date: 2000-10-12
Publication date: 2001-04-18
Anticipated expiration: 2020-10-12
Also published as: ITTO990185V0; DE20017446U1; ITTO990185U1; GB0025034D0; FR2799803A3; FR2799803B3; GB2355295B

Abstract

The fixing connects a vehicle cooling fan impeller 2 to an electric motor shaft 7 and comprises driving member 8 interference fitted to the shaft with a plurality of equiangularly spaced pins 10 extending therefrom on the opposite side to the motor. The pins pass through respective holes 11 in the impeller hub 3 and the portions protruding from the hub are engaged by a resilient expanding or contracting (not shown) ring 12. The protruding portions of the pins may be conical or recessed to receive the ring.

Description

2355295 IMPELLER/SHAFT FIXING The present invention relates to a system

for fixing an impeller to the shaft of an electric drive motor.

More specifically, the subject of the invention is a fixing system comprising:

a member for driving the impeller, which member can be fixed to the shaft of the electric motor and is intended to be coupled for rotation with the hub of the impeller, and axial retaining means for restraining the hub of the impeller axially on the shaft of the motor.

The object of the present invention is to provide an improved fixing system which can be produced easily and inexpensively and which enables the impeller to be mounted and removed quickly, possibly in an automated manner.

This and other objects are achieved, according to the invention, by a fixing system characterized in that the driving member has a plurality of projections which can extend through and beyond corresponding holes provided in a front wall of the hub of the impeller, and in that the axial retaining means comprise. a resilient member for coupling with the portions of the projections which protrude beyond the wall of the hub of the impeller so as to restrain the impeller axially on the driving member.

Further characteristics and advantages of the invention will become clear from the following detailed description, given purely by way of nonlimiting example, with reference to the appended drawings, in which:

Figure I is a partially sectioned side view of an electric fan comprising an impeller and an associated electric drive motor, Figure 2 is a partially axially sectioned, partial view showing a fixing system according to the invention, on an enlarged scale, and Figure 3 is a partial front view taken on the arrow III of Figure 2.

2 In Figure 1, an electric fan of the type which is intended, for example, to be associated with the radiator of the cooling system of an internal combustion engine for a motor -ehicle, is generally indicated 1.

The electric fan I comprises, in known manner, an impeller 2 having a substantially cup-shaped central hub 3 with a front wall 3a and a substantially cylindrical side wall 3b.

A plurality of shaped blades 4 extends from the hub 3 of the impeller. In the embodiment shown in Figure 1, the radially outermost ends of the blades 4 are connected by a peripheral ring 5.

An electric drive motor, generally indicated 6 in Figure 1, is coupled with the hub 3 of the impeller I arid extends at least partially inside the hub.

With reference to Figure 2, the electric motor 6 has a shaft 7 one end of which projects axially from the casing of the motor. A shaped driving member 8 is keyed to this end of the shaft 7, for example, by being driven onto it with interference.

In the embodiment shown, the driving member 8 has an inner tubular portion 8a which is driven onto the shaft 7, an intermediate, substantially bell-like portion 8b, and a substantially flat, annular, flange-like, radially outermost portion 8c.

In the radially outermost portion 8c of the driving member 8 there are holes 9 (of which only one is visible in Figure 2) in which respective shaped pins 10 are fixed, for example, by being driven with interference.

The pins 10 are preferably equiangularly spaced, as can be seen in particular in Figure 3, and extend from the side of the driving member 8 remote from the electric motor 6. The pins extend through and beyond corresponding holes I I (Figure 2) provided in the front wall 3a of the hub 3 of the impeller. In the embodiment shown by way of example, the portions of the pins 10 which extend through the holes I I in the hub of the impeller and which protrude beyond the front wall of the hub have conical cross-sections tapered towards the driving member 8.

The engagement of the pins 10 in the holes I I in the impeller couples the impeller and the shaft 7 of the electric drive motor 6 for rotation together.

3 In order to restrain the impeller 2 axially on the shaft 7 of the motor 6, a expansion spring ring 12 is fitted on the front wall 3a of the hub of the impeller and is engaged ingide the projecting portions of the pins 10, as can be seen in particular in Figure 3.

Many variants are possible.

In the first place, the conical shape of the pins is not absolutely essential. In general, it suffices for the pins 10 to have respective radial undercuts to permit the engagement of the retaining spring ring 12.

The retaining spring ring 12 may be engaged around the pins 10, retention in this case being achieved by virtue of a tendency of the spring ring 12 to contract radially.

Naturally, the principle of the invention remaining the same, the forms of embodiment and details of construction may be varied widely with respect to those described and illustrated purely by way of non-limiting example, without thereby departing from the scope of the invention as defined in the appended claims.

Claims

4 Claims

1. 1. A system for fixing an impeller (2) to the shaft (7) of an electric drive motor (6), comprising: a member (8) for driving the impeller, which member can be fixed to the shaft (7) of the motor and is intended to be coupled for rotation with the hub (3) of the impeller (2), and axial retaining means (12) for restraining the hub (3) of the impeller (2) axially on the shaft (7) of the motor (6), the system being characterized in that the driving member (8) has a plurality of projections (10) which can extend through and beyond corresponding holes (11) provided in a front wall (3a) of the hub (3) of the impeller (2), and in that the axial retaining means comprise a resilient member (12) for coupling with the portions of the projections (10) which protrude beyond the wall (3a) of the hub (3) of the impeller (2) so as to restrain the impeller (2) axially on the driving member (8).

2. A fixing system according to Claim I in which the portions of the projections (10) which protrude beyond the front wall (3a) of the hub (3) of the impeller have respective radial undercuts and the resilient member is a resilient ring (12) which can be engaged in the undercuts of the projections (10).

3. A fixing system according to Claim 2, in which the undercuts of the projections (10) of the driving member (8) face towards the axis of the driving member (8) and the resilient ring (12) is engaged in the undercuts by resilient expansion.

4. A fixing system according to Claim 2 or Claim 3, in which at least the portions of the projections (10) which protrude beyond the front wall (3a) of the hub (3) of the impeller (2) have conical cross-sections tapered towards the driving member (8).

5. A fixing system according to any one of the preceding claims, in which the projections (10) are driven with interference into corresponding seats (9) of the driving member (8).

6. A fixing system substantially as herein described with reference to and as illustrated in the accompanying drawings.