AU2808999A

AU2808999A - A valve body

Info

Publication number: AU2808999A
Application number: AU28089/99A
Authority: AU
Inventors: Klaus Franzke; Budi Tan
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1998-06-23
Filing date: 1999-05-12
Publication date: 2000-01-06
Anticipated expiration: 2019-05-12
Also published as: EP1090218A1; EP1090218B1; DE59906965D1; AU755148B2; WO1999067520A1; JP2003522867A

Description

Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

(ORIGINAL)

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a. 9 Name of Applicant: ROBERT BOSCH GmbH of Postfach 30 02 20, D-70442 Stuttgart, Germany Actual Inventor(s): Address for Service: Invention Title: DAVIES COLLISON CAVE, Patent Attorneys, of 1 Little Collins Street, Melbourne, Victoria 3000, Australia "A VALVE BODY" Details of Associated Provisional Application No: PP4292/98 The following statement is a full description of this invention, including the best method of performing it known to us: -1- P:\OPER\DBW\PP4292.98 12/5/99 -2- A VALVE BODY The present invention relates to a valve body, and is particularly useful for a throttle body with a butterfly valve.

Existing throttle bodies for fuel injection systems have an air intake bore which includes a butterfly valve. The butterfly valve regulates the air intake into the system. When the valve is closed, the vane of the valve has its edge adjacent the wall of the bore, to the extent that it virtually abuts the wall. There has always been a requirement that some air needs to be passed through the valve to the fuel injection system, when a vehicle is at rest, to enable S.o. the vehicle's engine to run idle. This requirement has become less and less over time, to the extent that the edge of the vane of the valve conforms closely to the diameter of the bore, which gives rise to the problem of the vane sticking. Undesired air leakage is also a problem with existing throttle bodies.

o: To deal with these two problems requires accurate machining of the bore and the vane to match one another, and the wall of the bore, in the past, has been coated with viscous material, such as Molybond M produced by Molybond Laboratories, to prevent sticking of the vane and air leakage. The material is however expensive, messy and difficult to apply. It is desired to therefore provide a useful alternative or a valve body which does not require coating with viscous material such as Molybond T M In accordance with the present invention there is provided a valve body including an intake bore and a valve in said bore having a vane with an edge movable to be adjacent the wall of said bore, characterised in that at least said edge of said vane is plated with deformable material which abuts said wall when said edge is adjacent said wall.

Advantageously, the deformable material may be tin.

Preferably the vane is plated in a process which involves plating a plurality of vanes.

P:\OPER\DBW\PP4292.98 12/5/99 -3- Advantageously, the valve body may be a throttle body with an air intake bore.

A preferred embodiment of the present invention is hereinafter described, by way of example only, with reference to the accompany drawings, wherein: Figure 1 is a cross-sectional view of a preferred embodiment of a throttle body; and Figure 2 is a detailed view of the area marked X in Figure 1.

A throttle body 2, as shown in Figures 1 and 2, has an air intake bore 4 which can be opened and closed by moving a butterfly valve 6, so as to regulate the flow of air into a fuel 10 injection system of a vehicle. The bore 4 is cylindrical in shape and has an inner wall 8. The valve 6 includes a circular shaped disk 10, which acts a vane, and is held in a slot 14 of a rotatable shaft 12. Opposite ends of the shaft 12 of the valve 6 extend into the wall 8 and the shaft 12 is supported by a bearing assembly. When the valve 6 is closed, the side or edge 16 of the vane 10 lies adjacent to the wall so as to close the air intake bore 4. The vane 10 is o.

made of rigid sheet metal, such as brass or aluminium.

To prevent air leakage and sticking of the edge 16 against the wall 8, the vane 10 is plated with a deformable material 18, for instance tin. At least the edge or side 16 needs to be plated with the material 18, but if desired the entire vane 10 can be coated with the material 20 18. The material 18 must be sufficiently soft and deformable so as to conform with the profile °OeWQ of the wall 8, as the vane 10 is moved. The material 18 must allow the vane 10 to move freely whilst at the same time sitting flush and abutting the wall 8, as shown in Figure 2, to prevent air leakage.

Plating the vane 10, as described above, provides significant advantages over using viscous material, such as Molybond

TM

Plating the vane 10 is considerably less expensive, does not leave any residual mess and as the material 18 conforms to the shape of the wall 8, precise and accurate machining of the bore to match the shape of the vane 10 is no longer required.

The cost of producing the throttle body 2 is therefore reduced.

The vane 10 may be plated with a material 18 either individually or with a group of P:\OPER\DBW\PP4292.98 12/5/99 -4vanes. For a group plating process, a number of vanes 10 may be stacked on top of one another, and plated, whereby only the edges 16 of the vanes 10 are significantly coated with the material 18. Group plating of the vane 10 further reduces costs.

Many modifications will be apparent to those skilled in the art without departing from the scope of the present invention as herein described with reference to the accompanying drawings.

The reference numerals in the following claims are not to be construed as imposing 10 any limitations on the claims.

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Claims

1. A valve body including an intake bore and a valve in said bore having a vane (10) with an edge (16) moveable to be adjacent the wall of said bore characterised in that at least said edge (16) of said vane (10) is plated with the deformable material (18) which abuts said wall when said edge (16) is adjacent said wall

2. A valve body as claimed in claim 1, wherein said deformable material (18) conforms with the profile of the wall as the vane (10) is moved.

3. A valve body as claimed in claim 2, wherein said vane (10) pivots freely whilst said edge (16) is flush with said wall *o A valve body as claimed in any one of the preceding claims, wherein said deformable material (18) is tin. A valve body as claimed in any one of the preceding claims, wherein said vane is plated with said deformable material (18) in a process which includes plating a plurality of said vane

6. A valve body as claimed in any one of the preceding claims, wherein said body (2) :is a throttle body and said bore is an air intake bore

7. A fuel injection system including a valve body as claimed in claim 6.

8. A vehicle engine including a fuel injection system as claimed in claim 7.

9. A vehicle including a vehicle engine as claimed in claim 8. DATED this 12th day of May, 1999 ROBERT BOSCH GmbH By its Patent Attorneys DAVIES COLLISON CAVE