Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
  • F02D9/08—Throttle valves specially adapted therefor; Arrangements of such valves in conduits
  • F02D9/10—Throttle valves specially adapted therefor; Arrangements of such valves in conduits having pivotally-mounted flaps
  • F02D9/1005—Details of the flap
  • F02D9/101—Special flap shapes, ribs, bores or the like
  • F02D9/1015—Details of the edge of the flap, e.g. for lowering flow noise or improving flow sealing in closed flap position
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
  • F02D9/08—Throttle valves specially adapted therefor; Arrangements of such valves in conduits
  • F02D9/10—Throttle valves specially adapted therefor; Arrangements of such valves in conduits having pivotally-mounted flaps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
  • F02D9/08—Throttle valves specially adapted therefor; Arrangements of such valves in conduits
  • F02D9/10—Throttle valves specially adapted therefor; Arrangements of such valves in conduits having pivotally-mounted flaps
  • F02D9/1035—Details of the valve housing
  • F02D9/104—Shaping of the flow path in the vicinity of the flap, e.g. having inserts in the housing

Definitions

• the invention relates to the throttle body for fuel injection device for internal combustion engine, and more particularly to a throttle body comprising a housing, in which is formed an air intake duct, and comprising a disc-shaped butterfly substantially circular or slightly elliptical, mounted on a median axis of rotation, transverse to the duct, and movable between a minimum open position, possibly zero, and a maximum open position for which the plane of the butterfly is oriented substantially parallel to the axis of the intake duct, in order to regulate the air flow admitted into the engine and to which the quantity of fuel injected per engine cycle must be linked.
• the most commonly used butterfly bodies include a butterfly in the shape of a thin circular disc of constant thickness, and a duct in the shape of a circular cylinder in the area where the butterfly pivots, the cross-section offered to air between the butterfly and the wall of the duct varying rapidly during the initial angular displacement of the butterfly from its minimum open position, especially when the latter is practically zero.
• FR-A-2 674 573 much less advantageous than the conventional butterfly in the form of a simple disc, and / or a conduit whose wall has at least a portion of complex shape (FR-2 663 710 and FR-A-2 694 963), expensive to produce by machining and / or molding of metal parts or difficult to produce by molding synthetic materials due to the need to use multiple or removable cores .
• FR-A-2 674 573 describes a throttle body as defined above, in which the side of the throttle which turns upstream, from the minimum open position, has, on its downstream face, a bulge of cross section (in a plane orthogonal to the axis of rotation) sufficiently small to allow rotation of the butterfly.
• the side of the butterfly rotating downstream at the opening and the cross section of the duct downstream of the minimum open position of said side turning downstream have, in general, shapes cooperating to give the cross section of the passage of air between them a law of variation as a function of the angle of rotation whose initial slope is less than the maximum slope of the law of variation during opening.
• the side of the throttle turning downstream is in the form of a thin half-disc and that the intake duct has, from the minimum opening position of the throttle, a section with a circular cross section. decreasing downstream, which makes a butterfly of complex shape cooperate with an intake duct with complex wall.
• FR-2 663 710 describes a butterfly body as defined above, the inlet duct of which has, upstream as downstream of the axis of rotation, a portion, one half of which is semi-circular and of constant radius, and the other half of which has, at each level of length from the axis of the intake duct, an elliptical cross section, the complex surface with elliptical cross section situated upstream respectively downstream of the axis of rotation being on the side of the butterfly which pivots upstream respectively downstream, at the opening.
• FR-A-2 694 963 describes a throttle body as defined above, and of the type in which the side of the throttle which turns upstream, respectively downstream, from the minimum open position a a form of semi-disc platjy and the intake duct has a wall which has, on the side in flat disc half-disc of the butterfly and upstream, respectively downstream, from the minimum opening position of the butterfly, a portion of surface evolving of complex shape cooperating with this side in a flat half-disc of the butterfly so that the passage section delimited between them increases at the start of the opening of the butterfly, as a function of the opening angle, less rapidly than in the case of a cylindrical duct.
• the intake duct has a straight cylindrical section with a section corresponding to the shape of the butterfly in the minimum open position, extending upstream and downstream from this minimum opening position, and has, upstream and downstream of the cylindrical section and along the path followed by the upstream and downstream sections of the butterfly valve to a defined opening angle of the latter, respective delimited areas by circular arcs centered on the axis of the intake duct and radii decreasing from the cylindrical section, and thus forming two portions of evolving surface of complex shape, which can be symmetrical to each other by relative to the axis of rotation, and each cooperating with one respectively, in shape of a flat half-disc, of the two halves of the butterfly
• the drawbacks of the butterfly bodies of the prior art presented above lie in their cost of production when they are made of metal and in the complexity of production of their mold and in the difficulties encountered in demolding, when these butterfly bodies are molded from a synthetic material, for example a thermoplastic material.
• a synthetic material for example a thermoplastic material.
• the molding of synthetic material of butterfly body according to FR-2,663,710 and FR-A-2,694,963 requires, due to the complex shapes of wall portions of the intake duct, the use of complex cores, comprising several parts, to be able to be released from the molded forms, but without being able to avoid the formation of plastic burrs at the joint planes of the core parts. It is therefore not possible to mold such butterfly bodies to their directly usable shape, without machining or deburring the finish.
• the present invention aims to provide a butterfly body that better meets those previously known to the requirements of practice, in particular in that it allows the required opening progressiveness to be obtained while being able to be produced by molding in synthetic material without presenting the disadvantages mentioned above, that is to say being obtainable directly in the final usable form, without particular difficulty of demolding nor particular complexity of production of the mold.
• the invention provides a butterfly body of the type defined above and known by FR-A-2 694 963, and which is characterized in that said evolving surface portion of complex shape, which cooperates with the side in flat disc half of the butterfly which rotates upstream, respectively downstream, at the opening, present, at each level along the axis of the intake duct and on half of the straight section of the duct on the same side of the axis of the duct that the flat semi-disc side of the butterfly, a section substantially in the form of a half ellipse, the half minor axis of which, perpendicular to the axis of rotation, gradually decreases up to a determined opening angle of the butterfly, while 'upstream, respectively downstream, of this portion of evolving surface and on the same half of the cross section of the duct, as well as on the other half of the cross section of the duct, on the side of the butterfly which turns downstream, respectively upstream, at the opening, and up to the level along the axis of the intake duct which corresponds to the
• the butterfly valve in the minimum opening position of the butterfly valve, is arranged in a straight cylindrical central section of circular cross section of the intake duct, said central section being substantially symmetrical along the axis of the intake duct, in part and on the other side of the axis of rotation, so that the butterfly, preferably slightly elliptical in shape, can be applied by its edge against the wall of the duct in this cylindrical central section, for an inclination of the butterfly relative to a plane transverse to the axis of the duct which is approximately 5 th , and without risk of jamming of the butterfly.
• the downstream diverging or respectively upstream converging sections of the intake duct are advantageously frustoconical from the downstream edge, respectively upstream of said cylindrical central section to the outlet, respectively the inlet of the intake duct, the half-angle at the top of the frustoconical shape which can be chosen to correspond to a favorable draft angle.
• the clearance thus produced in the conduit facilitates the mounting of a locally thickened butterfly, for example in the center, for the passage or integration of an axis of rotation, or on an edge.
• the shoulder on one face of the butterfly advantageously has a shape substantially of ellipsoidal cap of major axis substantially parallel to the axis of rotation but slightly offset downstream of the latter, and whose periphery is connected to the edge of the throttle side turning downstream, respectively upstream.
• the butterfly can thus be made of synthetic material, for example thermoplastic, and include a flat disc on which said shoulder is molded or attached, for example fixed by ultrasonic welding, the shoulder can, for example, be formed by a cup delimiting a closed space, or be molded with the butterfly by delimiting an open space downstream in the conduit.
• the housing with its intake duct can be molded in one piece to the final shape in a synthetic material, for example thermoplastic.
• FIG. 1 is a schematic view in axial section, perpendicular to the axis of rotation, of an example with shoulder in a closed bucket on the upstream face of the half of the butterfly rotating downstream at the start of opening ,
• FIGS. 2 and 3 are views similar to FIG. 1 for two variants, respectively with shoulder in open bucket downstream and with full shoulder, and
• Figure 4 is a view similar to Figure 3 of a symmetrical variant with respect to the axis of rotation, the air flow always coming from the top of the figure.
• the butterfly body 1 comprises a housing 2 made by molding in a synthetic material such as a thermoplastic material and obtained in its final form without further machining or deburring.
• An intake duct 3, of longitudinal axis 4, is formed in the housing 2.
• the axis of rotation 5 is pivotally mounted in a central section 7 of the conduit 3.
• the wall of the conduit 3 is a straight cylindrical wall of circular section, which extends substantially symmetrically on either side from the axis of rotation 5, along the longitudinal axis 4 of the conduit 3.
• the conduit 3 Downstream of the downstream edge 8 of the central section 7, the conduit 3 has a divergent downstream section 9, which is frustoconical from the downstream edge 8 to the outlet 10 of the conduit 3, at the bottom in FIG. 1.
• the cross section of the conduit 3 is therefore circular with a radius increasing progressively, monotonously from 1 upstream to the downstream.
• the wall of the conduit 3 is asymmetrical with respect to the diametral plane passing through the axis 4 of the conduit 3 and the center of the axis of rotation 5.
• the wall of the conduit 3 is defined by a section of frustoconical surface 12, which is coaxial with the axis 4 like the divergent 9 downstream, but converging from the inlet 13 of the conduit 3, in the upper part in FIG. 1, to the upstream edge 11 of the cylindrical central section 7.
• the wall of the duct 3 is delimited by a portion of evolutive surface 14, of complex shape, extending upstream of the upstream edge 11 of the central section 7 to a position opposite the edge of the butterfly 6 when the latter is inclined on the transverse plane, perpendicular to the axis 4 of the conduit 3 and passing through the center of the axis of rotation 5, at a particular angle, between approximately 30 ° and approximately 50 °, and upstream of this evolutive surface portion 14, the wall of the duct 3 is delimited by a section of converging surface 15, which converges from the inlet 13 of the duct 3.
• the corresponding cross section half of the duct 3 has a substantially seri-elliptical shape, which progressively evolves from a semicircular shape at the upstream edge 11 of the central section 7 to a half -semi-elliptical straight section of smaller half-minor axis at the connection between the evolving surface portion 14 and the converging surface section 15.
• the corresponding straight half-section of the conduit 3 has the form d 'a half-ellipse whose half-minor axis, perpendicular to the axis of rotation 5, gradually decreases, while its major axis remains constant and equal to the diameter of the cylindrical central section 7.
• the butterfly 6 advantageously made of synthetic material such as a thermoplastic material, consists of a disc 16 which is substantially circular or slightly elliptical, of generally constant thickness, but which may include reinforcing ribs, passing through a diametrical slot of the axis of rotation 5, and the side of the throttle valve 6 which rotates downstream, at the opening of the throttle valve, that is to say, taking into account the direction of rotation of the throttle valve when opening ture indicated by an arrow in FIG. 1, the half of the butterfly to the right of the axis 5 in this FIG.
• This shoulder 17 is constituted by a bucket projecting upstream of the conduit 3 and whose downstream periphery is connected to the downstream edge of the butterfly half-disc 6 which rotates downstream at the opening.
• the wall of the bucket 17 which is opposite the wall of the duct 3 has substantially the shape of an ellipsoidal cap whose major axis is parallel to the axis of rotation 5, offset by a small distance downstream from this axis 5 , and slightly lower than the diameter of the central section 7, and the minor axis of which is chosen to give this wall of the shoulder 17 a delimiting profile, with the profile opposite the wall of the duct 3, a passage section for the air admitted to the engine which increases less quickly, in comparison with a butterfly in a flat disc rotating in a cylindrical duct than, when the butterfly 6 is opened from its minimum open position, in which the flat disc 16 and most of the shoulder 17 are housed in the central cylindrical section 7, in a position such that the flat disc 16 is inclined by a few degrees on the transverse plane perpendicular to the axis 4 passing through the center of the axis of rotation 5.
• the half-disc carrying the shoulder 17 and rotating downstream at the opening is slightly inclined downstream, while, on the opposite side of the axis 5, the flat half-disc, without shoulder, turning upstream at the opening of the butterfly 6, is slightly inclined upstream.
• the profile of the edge of the shoulder 17 is chosen to allow the rotation of the half-disc which carries it downstream, without contact of the shoulder 17 with the wall of the conduit 3.
• the butterfly 6 is shown in an intermediate position between its minimum open position and its maximum open position, in which the flat disc 16 of the butterfly 6 is oriented substantially parallel to the axis 4 of the conduit 3.
• FIG. 2 differs from the example of FIG. 1 only by the production of the shoulder, which is a bucket 17 'molded in one piece with the butterfly 6 'so as to delimit, in the half-butterfly pivoting downstream at the opening, an open space towards 1' downstream in the conduit 3 of the same shape as in FIG. 1, so that identical references are used to locate identical shaped parts.
• the shoulder which is a bucket 17 'molded in one piece with the butterfly 6 'so as to delimit, in the half-butterfly pivoting downstream at the opening, an open space towards 1' downstream in the conduit 3 of the same shape as in FIG. 1, so that identical references are used to locate identical shaped parts.
• FIG. 3 differs from FIGS. 1 and 2 only by the production of the shoulder 17 ", which is solid and molded and attached to the upstream face of the half-disc 16 pivoting downstream at the opening, or possibly molded in one piece with this half of disc 16 to form the butterfly 6 ".
• the housing 2 and its conduit 3 are identical.
• FIG. 4 is symmetrical to that of FIG. 3 with respect to the axis of rotation 5 but the air flow always circulates from top to bottom in the figure. Therefore, the shoulder 17a is on the downstream face of half of the disc 16a of the butterfly 6a which pivots upstream at the opening, while the other half of the disc 16a, which pivots downstream at the opening moves opposite the evolving surface 14a, downstream of the downstream edge 11a of the central circular and straight cylindrical section 7a of the conduit 3a.
• the duct 3a Downstream of the downstream edge 11a and of the evolving surface 14a, the duct 3a has respectively a frustoconical diverging portion 12a and a diverging portion 15a, on the corresponding halves of the cross section, which extend to the outlet 13a of the duct 3a. Upstream of the upstream edge 8a of the central section 7a, the conduit 3a has a frustoconical convergent 9a from its inlet 10a in the housing 2a of the throttle body 1a.
• This variant has the same advantages as the previous ones concerning the ease of molding and the progression of variation of the air flow. However, it may prove slightly unfavorable in terms of turbulence, under certain conditions of use.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Lift Valve (AREA)
• Control Of Throttle Valves Provided In The Intake System Or In The Exhaust System (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=9484824

Family Applications (1)

Country Status (8)

Cited By (1)

Families Citing this family (29)

Family Cites Families (8)

• 1995
  • 1995-11-22 FR FR9513885A patent/FR2741392B1/fr not_active Expired - Lifetime
• 1996
  • 1996-11-19 ES ES96939142T patent/ES2138387T3/es not_active Expired - Lifetime
  • 1996-11-19 WO PCT/FR1996/001822 patent/WO1997019264A1/fr active IP Right Grant
  • 1996-11-19 US US09/068,564 patent/US6047950A/en not_active Expired - Lifetime
  • 1996-11-19 DE DE69604084T patent/DE69604084T2/de not_active Expired - Lifetime
  • 1996-11-19 BR BR9611747A patent/BR9611747A/pt not_active IP Right Cessation
  • 1996-11-19 CN CN96198505A patent/CN1086219C/zh not_active Expired - Fee Related
  • 1996-11-19 EP EP96939142A patent/EP0862687B1/de not_active Expired - Lifetime

Non-Patent Citations (1)

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