GB2252641A

GB2252641A - A system for regulating air flow along a throttled body (1) of a vehicle internal combustion enigine supply device.

Info

Publication number: GB2252641A
Application number: GB9126024A
Authority: GB
Inventors: Francesco Morini; Paolo Venturi
Original assignee: Weber SRL
Current assignee: Weber SRL
Priority date: 1990-12-07
Filing date: 1991-12-06
Publication date: 1992-08-12
Anticipated expiration: 2011-12-06
Also published as: DE4140353A1; FR2670243A1; FR2670243B1; IT9067974A1; IT9067974A0; GB2252641B; IT1241015B; GB9126024D0

Description

2252541 SYSTEM FOR REGULATING AIR FLOW ALONG A THROTTLED BODY OF A VEHICLE

INTERNAL COMBUSTION ENGINE SUPPLY DEVICE The present invention relates to a system for regulating air flow along a throttled body of a vehicle internal combustion engine supply device.

on vehicle internal combustion engine air supply devices, air flow is regulated along the throttled bodies upstream from the air manifold. At present, air flow is generally regulated using electromechanical means, such as an electric motor, the rotor of which is connected to a hub on which a throttle valve is fitted inside the body. The electric motor is controlled by an electronic system, and elastic means are provided for counteracting a variation in the throttle setting when switching from the minimum to the maximum open setting of the throttled body.

If the electric motor is disabled. the elastic means provide for fully closing the throttled body. one of the main drawbacks of regulating air flow electromechanically is that, if for any reason (a fault on the electric motor or the electric part of the supply circuit, etc.) supply to the electric motor is cut off. the aforementioned elastic means shut off the throttled body. thus cutting off the engine. Should this occur in transit, the vehicle is totally disabled until the fault is repaired, with considerable inconvenience to the user.

It is an object of the present invention to provide a system for regulating air flow along a throttled body of a vehicle internal combustion engine supply device. designed to overcome the aforementioned drawback, i.e. which enables the vehicle to continue operating, albeit at reduced speed.

Further aims and advantages of the present invention will be disclosed in the following description.

According to the present invention, there is provided a system for regulating air flow along a throttled body of a vehicle internal combustion engine supply device, characterised by the fact that it comprises:

first means for setting a throttle valve, installed inside said body, between a minimum open setting (corresponding to minimum supply of said internal combustion engine, i.e. with the engine running and the vehicle stationary) and a maximum open setting and vice versa; and second means which, in the event of failure of said first means, set said throttle valve to higher than said minimum open setting, for enabling albeit reduced supply for operating said engine and enabling said vehicle to continue operating albeit at reduced speed.

A preferred non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which:

Fig.1 shows a section of a throttled body featuring a regulating system in accordance with the teachings of the present invention; Fig.2 shows a side view of the Fig.1 body; Fig.s 3, 4 and 5 show schematic views of three settings of a throttle valve installed inside the Fig.1 body.

Number 1 in Fig.1 indicates a throttled body for supplying air to the air manifold of a vehicle internal combustion engine supply device. Body 1 is fitted inside with a throttle valve 2 angularly integral. by means of screws 3. with a shaft 4 fitted diametrically through body 1 and supported at the lateral walls of body 1 by respective bearings 5. The system for regulating the setting of throttle 2 comprises first electromechanical control means for setting throttle 2 between a minimum open setting (corresponding to minimum supply of the engine, i.e. with the engine running and the vehicle stationary) and a maximum open setting and vice versa; and second means which. in the event of failure of said first means, set throttle 2 to higher than the minimum open setting. for enabling albeit reduced supply for operating the engine and enabling the vehicle to continue operating albeit at reduced speed.

As shown in Fig.1, body 1 forms one piece with a lateral housing 6 having a cover 7 and housing said first means consisting of an electric motor 8 supplied by an electronic control system 9 (shown only schematically). In the embodiment shown, electric motor 8 comprises a stator 11 defined by an annular element supporting a toroidal winding 12 and integral with body 1; and a rotor 13 defined by a cylindrical center portion 14 and two U-shaped pole pieces 15 surrounding diametrically-opposite parts of stator 11. Center portion 14 of rotor 13 is angularly integral with an end portion of shaft 4 outside body 11.

As shown in Fig.s 1 and 2. on the side diametrically opposite housing 6, body 1 forms one piece with a second housing 16 housing said second means, which, in the embodiment shown, consist of a lever 17, a spring 23 and an adjusting screw 31. In housing 16, lever 17 is angularly integral with a portion of shaft 4. Lever 17 presents a cylindrical center portion 18 from a lateral portion of which there extends a substantially tangent arm 21 thinner than the length of portion 18. Portion 18 presents an axial through hole 19 through which shaft 4 is fitted and inside which lever 17 is connected angularly to shaft 4. From the inner lateral wall of housing 16, there extends a substantially radial projection 22 which, in certain conditions, is contacted by arm 21 of lever 17.

Housing 16 also houses spring 23, which is a spiral spring with a first end 24 secured to a portion of housing 16 substantially diametrically opposite projection 22. Spring 23 presents a portion 25 commencing from end 24 and describing, in a spiral, an arc of about 300; and a substantially U-shaped portion 26 housed in a substantially U-shaped recess 27 formed in center portion 18, in the portion following that from which arm 21 extends. Recess 27 surrounds hole 19 with its center portion facing projection 22, so that portion 26 of spring 23 is angularly integral with portion 18 and, consequently, shaft 4. Spring 23 presents a second end 28 originating from- portion 26 and extending outwards of recess 27 close to the point at which end 24 is secured to the fixed portion of housing 16. Housing 16 also houses adjusting screw 31, the end portion of which acts as a contact for second end 28 of spring 23.

As we all know, the setting of throttle 2 is determined by the angular position of the accelerator pedal, which is converted by a transducer into an electric signal supplied to electronic control system 9. This in turn controls electrical supply to motor 8 for rotating rotor 13 and shaft 4. Fig.3 shows the position of lever 17 to which the positions described hereinafter are referred. In this position, wherein body 1 is fully closed by throttle 2, arm 21 is positioned contacting projection 22. As of this position, throttle 2 may be so set, by means of screw 31, as to supply and operate the engine at reduced speed, and so enable operation of the vehicle at a predetermined speed. This is done, naturally with motor 8 disabled, by extending and so pressing screw 31 on to end 28 of spring 23, so as to rotate lever 17 and throttle 2 into the position shown in Fig.4.

In actual use, therefore, motor 8 determines all the settings of throttle 2, including the minimum setting shown in Fig.5. wherein the plane of throttle 2 forms an angle al with the transverse axis of body 1. When set to minimum,, end 28 of spring 23 is obviously flexed to a greater extent than in the Fig.4 position wherein the angle a2 between the plane of throttle 2 and the transverse axis of body 1 is greater than al. When the engine is off, or when driving with motor 8 disabled, throttle 2 always assumes the Fig.4 position, thus enabling startup or continued operation of the vehicle, regardless of the fault on motor 8.

The advantages of the present invention will be clear from the foregoing description.

Even in the event of electrical, mechanical or any other type of fault on motor 8 or the electromechanical control governing throttle 2. the system according to the present invention provides for supplying and operating the engine sufficiently to keep the vehicle going, albeit at reduced speed, thus enabling the user to reach the nearest repair garage.

To those skilled in the art it will be clear that changes may be made to the system as described and illustrated herein without, however. departing from the scope of the present invention. For example, spring 23 may be replaced by two springs, one for counteracting rotation by motor 8, and the other for effecting the Fig.4 setting of throttle 2. Also. motor 8 may be other than as described herein.

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Claims

1) - A system for regulating air flow along a throttled body of a vehicle internal combustion engine supply device, characterised by the fact that it comprises:

first means for setting a throttle valve r installed inside said body, between a minimum open setting (corresponding to minimum supply of said internal combustion engine, i.e. with the engine running and the vehicle stationary) and a maximum open setting and vice versa; and second means which, in the event of failure of said first means set said throttle valve to higher than said minimum open setting. for enabling albeit reduced supply for operating said engine and enabling said vehicle to continue operating albeit at reduced speed.

2) - A system as claimed in Claim 1, characterised by the fact that said second means comprise elastic means fitted to a shaft with which said throttle valve is angularly integral; said elastic means counteracting the action of said first means when switching between said minimum to said maximum open setting of said throttle valve 0 3) - A system as claimed in Claim

2. characterised by the fact that said second means comprise means for adjusting said setting of said throttle valve assumed in the event of failure of said first means X said adjusting means being applied to said elastic means 4) - A system as claimed in Claim 3, characterised by the fact that said elastic means comprise a substantially spiral spring having a first end secured to a fixed part a first portion angularly integral with said shaft j and a second flexible free end; said adjusting means comprising a screw having one end pressing on said second end of said spring 5) - A system as claimed in Claim 4. characterised by the fact that said second means comprise a lever having a center portion angularly integral with said shaft; said first portion of said spring being housed in a recess formed in said portion A system as claimed in Claim Si characterised by the fact that said spring comprises, commencing from said first end a second portion describing a spiral arc; and said first portion from which extends said second end outside said recess 7) - A system as claimed in Claim 6. characterised. by the fact that said first portion is substantially U-shaped with a center portion diametrically opposite said first end said recess also being U-shaped and formed about a hole substantiall - 10 formed in said portion and engaged by said shaft 8) - A system as claimed in at least one of the foregoing Claims from 5 to 7, characterised by the fact that said lever comprises an arm extending from said portion in such a direction as to contact a fixed element when said body is fully closed by said throttle valve 9) - A system as claimed in at least one of the foregoing claims, characterised by the fact thatthe outer lateral surface of said body presents.

preferably in one piece. two diametrically-opposed housings respectively housing said first means and said second means 0 10) - A system as claimed in at least one of the foregoin g Claims from 3 to 9 dependent on Claim 2.

characterised by the fact that said first means comprise an electric motor controlled by an electronic control system and having a rotor angularly integral with said shaft. and a stator having an electric winding and integral with said body 11) - A system for regulating air flow along a throttled body of a vehicle internal combustion engine supply device, substantially as described and illustrated herein with reference to the accompanying drawings.