JPH11101137A - Throttle valve assembly and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a clearance between the outer peripheral surface of a valve and a bore wall surface and reduce machining cost and assembly cost by providing a plate-like valve for opening/closing a bore in a body by rotation, with a sealing member formed of plastically deformable soft material and brought into contact with the bore wall surface into a totally closed position. SOLUTION: A throttle body 1 is formed of resin material such as nylon resin, and a valve main plate 25 is rotatably accommodated therein. The valve main plate 25 is formed in nearly disc shape, and its outer peripheral part is formed as a fitting part 251 forming an upper side stepped face. A sealing member 20 of approximately ring plate shape formed of plastically deformable material such as ethylene tetrafluoride resin softer than a bore wall surface 8 is fitted to the fitting part 251 of the valve main plate 25. The sealing member 20 is fitted using a holding member 21 and fixed by heat-caulking the tip part of a weight part 22 protruded onto the holding member 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throttle valve assembly mainly used for an intake throttle device of an automobile engine.

[0002]

2. Description of the Related Art An example of a conventional throttle valve assembly will be described with reference to FIGS. 14 is a front sectional view of the throttle valve assembly, FIG. 15 is a right side view of the same, and FIG. 16 is a side sectional view. The throttle valve assembly is used as an intake throttle device for an automobile engine, and has a throttle body 1 forming a substantially cylindrical bore 10 through which intake air flows, and a throttle rotatably provided on the throttle body 1. The throttle valve includes a valve shaft 3 and a plate-shaped throttle valve 2 attached to the throttle valve shaft 3 by a screw 23 and opening and closing the bore 10 by rotation. The rotation of the throttle valve 2 increases or decreases the gap 9 (see FIG. 16) between the outer peripheral surface of the valve 2 and the bore wall surface 8 of the throttle body 1, thereby adjusting the flow rate of the air flowing through the bore 10. .
The throttle body 1 corresponds to the body according to the present invention, the throttle valve shaft 3 corresponds to the valve shaft according to the present invention, and the throttle valve 2 corresponds to the valve according to the present invention.

In FIG. 14, one end (the right end in FIG. 14) of the throttle valve shaft 3 penetrates the wall of the throttle body 1 and protrudes from the side surface of the body. A throttle lever 4 is fixed to an end of the shaft by a nut 5. The throttle lever 4 is provided with a stopper 7 that can contact an idle flow rate adjusting screw 6 described later. Although not shown, the throttle lever 4 is connected to an accelerator pedal via an accelerator link mechanism.

On the other hand, an idle flow rate adjusting screw 6 is screwed to a mounting projection 11 protruding from the side surface of the throttle body 1. The tip of the idle flow rate adjusting screw 6 can abut on the stopper 7 of the throttle lever 4. In FIG.
The throttle lever 4 is turned in the valve opening direction (see the arrow 12 in the figure) by depressing an accelerator pedal (not shown), and the throttle valve 2 is opened.
When the depression force on the accelerator pedal is released, the throttle valve 2 is urged together with the throttle lever 4 in the valve closing direction (see arrow 13 in the figure) by the elasticity of a return spring (not shown), and the stopper 7 of the throttle lever 4 is idled. It is returned to the fully closed position where it comes into contact with the flow rate adjusting screw 6.

[0005] As shown in FIG. 14, the throttle body 1 is provided with a bypass passage 18 that bypasses the throttle valve 2. An idle speed control valve (ISCV) 14 is incorporated in the bypass passage 18. The ISCV 14 is controlled by an unillustrated engine control computer (also referred to as an ECU) in accordance with the state of the engine and the vehicle to adjust the amount of air flowing through the bypass passage 18 during idling. The flow of the air flowing through the bypass passage 18 is indicated by an arrow 15 in FIG.

The throttle valve assembly includes a bypass passage 1 incorporating an ISCV 14 and an amount of air passing through a gap 9 between a bore 10 of the throttle body 1 and the throttle valve 2.
8 is fed back to the ECU as to whether or not the total amount of air passing through the engine 8 is the amount of air required for the engine. The ISCV 14 is operated by the ECU to adjust the amount of air passing through the bypass passage 18 and to adjust the amount of air required for the engine. The quantity is controlled to the required value. In the engine, in addition to the amount of air passing through the gap 9 and the air passing through the bypass passage 18, there is a blow-by gas or the like passing through a passage for blow-by processing.

[0007] In addition to the above-described throttle valve assembly, there is one shown in a front sectional view in FIG. 17 as an intake throttle device for an automobile engine. The throttle valve assembly shown in FIG. 17 is provided with an idle speed adjusting device 16 instead of the bypass passage 18 and the idle speed adjusting valve of the previous example (see FIG. 14). The idle speed adjusting device 16 has a built-in actuator such as a motor and a solenoid valve, and its output shaft 161 is connected to the throttle valve shaft 3. Idle speed adjustment device 16
Adjusts the flow rate of air passing through the gap 9 (see FIG. 16) between the bore 10 and the throttle valve 2 by opening and closing the throttle valve 2 according to the state of the engine and the vehicle by the ECU. Since the configuration other than the above is the same as that of the previous example, the same portions are denoted by the same reference numerals and overlapping description will be omitted. In addition, the idle speed adjusting device 16
May be connected to the throttle lever 4 instead of the throttle valve shaft 3 in some cases.

[0008]

In each of the above two examples of the throttle valve assembly, the amount of air when the throttle valve 2 is closed needs to be extremely small in consideration of reduction of fuel consumption and the like. is there. To cope with this, the outer peripheral surface of the throttle valve 2 and the bore wall surface 8 of the throttle body 1 are each processed with high precision by post-processing and the throttle valve 2 is assembled with high precision to reduce the gap 9 between the two. Although there is a means, there remains a problem that processing costs and assembly costs are high.

[0009] As shown in FIG.
There is a throttle valve 2 having a synthetic resin sub-valve plate portion 19 protruding from the outer peripheral surface (for example, Utility Model Registration Publication No. 25).
No. 28281). In the throttle valve 2, an outer peripheral surface of the valve 2 and a bore wall surface 8 of the throttle body 1 are provided.
Malfunction that is expected when the gap 9 between them is reduced to reduce the amount of air leakage and optimize the idle speed,
That is, the bite of the sub-valve plate portion 19 in the closed state at the time of high temperature due to the pressure contact with the bore wall surface 8 is prevented by the compression deformation of the sub-valve plate portion 19 (in the above-mentioned publication, the right column of page 2 ( Column 4) see lines 6-12). Therefore, in the throttle valve 2 as well, in order to reduce the gap 9 between the outer peripheral surface of the sub-valve plate portion 19 and the bore wall surface 8, the sub-valve plate portion 1
9, it is necessary to form the outer peripheral surface and the bore wall surface 1 with high precision by post-processing, respectively, and to assemble the throttle valve 2 with high precision. Therefore, there still remains a problem that processing cost and assembly cost are high. Become.

Further, there is a throttle valve which uses an elastic material for a member corresponding to the sub-valve plate portion 19 and makes elastic contact with the bore wall surface when fully closed (for example, US Pat.
098,064, U.S. Patent No. 5,181,492). However, with the elastic material, it is not possible to finely adjust the amount of air between the fully closed position of the throttle valve and the opening position where the elastic material separates from the bore wall surface. In addition, there is a problem in bending and durability of the elastic material, which is not preferable.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to reduce the gap between the outer peripheral surface of the valve and the bore wall surface of the body. Another object of the present invention is to provide a throttle valve assembly that can reduce processing costs and assembly costs.

[0012]

According to the first aspect of the present invention, there is provided a body for forming a bore through which air flows.
A throttle valve assembly comprising: a valve shaft rotatably provided on the body; and a plate-shaped valve attached to the valve shaft and opening and closing the bore by rotation. The seal member is formed so as to be able to contact the bore wall surface, and the seal member is formed of a plastically deformable material softer than the bore wall surface. According to the throttle valve assembly of claim 1, after assembling the valve to the body,
By closing the valve to the fully closed position, the seal member comes into contact with and is shaped by the bore wall surface of the body, so that the outer peripheral surface of the valve conforming to the bore wall shape can be easily obtained with high precision. Thereby, the gap between the outer peripheral surface of the valve and the bore wall surface of the body can be reduced, and the processing cost and the assembly cost can be reduced.

According to a second aspect of the present invention, there is provided the throttle valve assembly according to the first aspect, wherein a position opened by a predetermined opening from the fully closed position of the valve is set to an idle opening after the sealing member is formed. It is characterized by. According to the throttle valve assembly of the second aspect, by setting the valve to the idle opening after the molding of the seal member is completed, the seal member is set when the valve after the molding of the seal member is set to the idle opening. A predetermined amount of gap can be secured between the body and the bore wall surface of the body, and a predetermined amount of air can flow.

According to a third aspect of the present invention, there is provided the throttle valve assembly according to the first aspect, wherein the seal member is provided with a ventilation portion penetrating the front and back surfaces thereof. According to the throttle valve assembly of the third aspect, when the valve is fully closed, a constant amount of air can flow from the ventilation portion.

According to a fourth aspect of the present invention, there is provided the throttle valve assembly according to the first aspect, wherein the seal member is provided intermittently in a circumferential direction of the valve. According to the throttle valve assembly of the fourth aspect, when the valve is fully closed, a constant amount of air can flow through the gap between the seal members.

According to a fifth aspect of the present invention, there is provided a method of manufacturing the throttle valve assembly according to any one of the first to fourth aspects,
After assembling the valve to the body, by closing the valve, when the seal member is brought into contact with the bore wall surface of the body and shaped, applying heat to the seal member to form the bore wall shape and then cooling. Features. Claim 5
According to the method of manufacturing the throttle valve assembly described above, the seal member is softened by applying heat during the molding of the seal member, so that the seal member can be easily molded into a shape conforming to the bore wall shape.

According to a sixth aspect of the present invention, there is provided the throttle valve assembly according to any one of the first to fourth aspects, wherein the plastically deformable material is made of a resin material. According to the throttle valve assembly of the sixth aspect, corrosion of the seal member due to adhesion of water or freezing can be prevented, and weight can be reduced, as compared with a seal member in which the plastically deformable material is made of a metal material.

According to a seventh aspect of the present invention, there is provided the throttle valve assembly according to any one of the first to fourth aspects, wherein the body is formed of a resin material. According to the throttle valve assembly of the seventh aspect, as compared with a body formed of a metal material, the molding dimensions and surface roughness of the bore wall surface are better, and post-processing after molding can be omitted, and the production of the body can be omitted. Cost can be reduced. Further, corrosion due to adhesion of water, freezing and the like can be prevented, and the weight can be reduced.

An eighth aspect of the present invention is the throttle valve assembly according to the seventh aspect, wherein the plastically deformable material is a resin material. According to the throttle valve assembly of the eighth aspect, it is possible to prevent icing between the body and the valve in a cold state, and to avoid a malfunction of the valve due to the icing. In connection with this, it is also possible to abolish the heating device for freezing prevention by a hot water system, an electric heating system, or the like. Also,
By eliminating the heating device, cost reduction, weight reduction and compactness can be achieved, and deterioration and corrosion due to heating of the body and the seal member can be avoided.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 Embodiment 1 will be described with reference to FIGS. In the first embodiment, a part of the conventional example is modified. Therefore, the modified part will be described in detail, and the parts that are considered to have the same or substantially the same configuration as the conventional example (see FIGS. The same reference numerals are given and duplicate descriptions are omitted. Further, in the embodiments other than the first embodiment, the same description will not be repeated.

FIG. 1 shows a side sectional view of the throttle valve assembly.
In FIG. 2 showing a cross-sectional view taken along the line AA of FIG. 1, the throttle body 1 is formed of a resin material such as a nylon resin or a polyphenylene sulfide resin, that is, is formed by resin molding. Further, the throttle valve 2 has a main valve plate 25 serving as a main body, a seal member 20 provided on an outer peripheral portion of the main valve plate 25, and a holding member 21 for holding the seal member 20. The valve main plate 25 has the seal member 20 attached with the following attachment structure. FIG. 3 is a cross-sectional view of the periphery of the seal member 20.

As shown in FIG. 3, the valve main plate 25 is formed in a substantially disk shape, and has a mounting portion 251 that forms an upper stepped surface on the outer peripheral portion. The mounting portion 251 has a protruding shaft-like holding portion 22 located at each of the opening and closing ends of the throttle valve 2 (see FIGS. 1 and 2). The valve main plate 25 is formed of, for example, ethylene tetrafluoride resin (PTFE, trade name: Teflon), that is, resin molded.

The seal member 20 is provided on the valve main plate 2.
5 is formed in a substantially ring plate shape corresponding to the mounting portion 251, and a mounting hole (symbol omitted) for fitting with both holding portions 22 of the valve main plate 25 is formed. The seal member 20 is a plastically deformable material that is softer than the bore wall surface 8 of the throttle body 1 and has good sliding properties with the bore wall surface 8, low sliding resistance, and is resistant to humidity, chemicals, water, and other environments. For example, durable ethylene tetrafluoride resin (PT
(FE, trade name; Teflon).

The holding member 21 is provided with the valve main plate 25.
The mounting hole 251 is formed in a substantially ring plate shape corresponding to the mounting portion 251, and has a mounting hole (symbol omitted) for fitting to both the holding portions 22 of the valve main plate 25. The holding member 21 is formed of, for example, the same material as the valve main plate 25.

When the seal member 20 is mounted, first, the mounting hole of the seal member 20 is inserted into the valve main plate 2.
5, the seal member 20 is disposed on the mounting portion 251 of the valve main plate 25. Next, the mounting hole of the holding member 21 is inserted into the valve main plate 25.
Of the holding member 21
Is disposed on the seal member 20. Next, the sealing member 20 is fixed to the valve main plate 25 by heat caulking the tip of the holding portion 22 protruding above the holding member 21.

The seal member 20 has an outer diameter larger than the outer diameters of the valve main plate 25 and the holding member 21. The valve main plate 25 and the holding member 21 have substantially the same outer diameter. Here, the outer diameters of the seal member 20, the valve main plate 25, and the holding member 21 refer to the fully closed position of the throttle valve 2 (for example, the bore 10).
Is set at a position inclined by about 10 ° with respect to a plane orthogonal to the axis of. ) Means the outer diameter on the plane projection plane. As a result, as shown in FIG. 1, at the fully closed position of the throttle valve 2, a gap 26 is formed between the bore wall surface 8 of the throttle body 1 and the outer peripheral surface of the mounting portion 251 of the valve main plate 25. A gap 27 is formed between the wall surface 8 and the outer peripheral surface of the holding member 21. The gap 26 and the gap 27 are narrow enough to prevent the seal member 20 from deforming more than a predetermined amount and to prevent the valve main plate 25 and the sandwiching member 21 from biting the bore wall surface 8.
mm. The gap 26 and the gap 27 may be set in consideration of an allowable value of an increase in the amount of air when the seal member 20 is damaged.

Further, as shown in FIG.
The mounting portion 251 and the outer peripheral portion of the holding member 21
Stepped groove 25 that forms space 24 between seal member 20
2,211 are formed. The space 24 facilitates the deformation of the seal member 20 and limits the escape amount during the deformation to a predetermined amount. The shape and size of the space 24 are selected according to conditions such as characteristics and dimensions (thickness and length) of the seal member 20, and may be minute gaps.

The seal member 20 has a gap (see reference numeral 9 in FIG. 16) between the outer peripheral surface of the throttle valve 2 (corresponding to the outer peripheral surface of the seal member 20) and the bore wall surface 8 of the throttle body 1. Seal by contact.
Incidentally, the seal member 20 is formed as follows. As shown in FIG. 4 which is a partial cross-sectional view of the seal member 20 before molding, the seal member 20 initially has an inner diameter of the bore wall surface 8 (ie, before the state shown in FIG. 3) (the throttle valve in the fully closed position). The inner diameter corresponding to the outer diameter of 2 is attached to the valve main plate 25 with an outer diameter larger than the inner diameter corresponding to the two-dot chain line 8 in FIG. Then, after assembling the throttle valve 2 to the throttle body 1 in a state of opening a predetermined opening, the outer peripheral surface of the seal member 20 is brought into contact with the bore wall surface 8 by closing the throttle valve 2 to the fully closed position. Thereby, as shown in FIG. 3, the sealing member 20 is shaped into a permanent deformation state by utilizing its plastic deformation. The outer peripheral end 201 of the seal member 20
Is formed in a tapered cross section. Therefore, when the seal member 20 is formed, the outer peripheral end portion 201 can be slightly adapted to the shape of the bore wall surface 8 of the throttle body 1. Further, it is possible to surely and quickly perform the adaptation by applying heat.

According to the throttle valve assembly described above, after the throttle valve 2 is assembled to the throttle body 1 and the throttle valve 2 is closed to the fully closed position, the seal member 20 comes into contact with the bore wall surface 8 of the throttle body 1. However, since the outer peripheral surface of the throttle valve 2 conforming to the shape of the bore wall surface 8 can be easily obtained with high precision. Thereby, the gap between the outer peripheral surface of the throttle valve 2 and the bore wall surface 8 of the throttle body 1 can be reduced. At the same time, the outer peripheral surface of the throttle valve 2 and the bore wall surface 8 of the throttle body 1 do not need to be formed with high precision by post-processing, and the throttle valve 2 is assembled with high precision as compared with the conventional one. Since the necessity is eliminated, the processing cost and the assembling cost can be reduced.

Further, even after the seal member 20 is formed, it can be formed in a direction in which the outer diameter is further reduced in accordance with the deformation of the body and the valve main plate 25. This makes it possible to prevent sticking of the throttle valve 2 while keeping the gap between the outer peripheral surface of the throttle valve 2 and the bore wall surface 8 of the throttle body 1 small over a long period of time.

Further, the position where the throttle valve 2 is opened by a predetermined opening from the fully closed position can be set as the idle opening after the sealing member 20 is formed. Then, by setting the throttle valve 2 to the idle opening after the molding of the seal member 20 is completed, the seal member 20 and the throttle body 1 are set when the throttle valve 2 after the molding of the seal member 20 is set to the idle opening. Bore wall 8
A gap of a predetermined amount can be secured between them, and a predetermined amount of air can flow.

After the throttle valve 2 is assembled to the throttle body 1, the throttle valve 2 is closed to the fully closed position so that the seal member 20 is brought into contact with the bore wall surface 8 of the throttle body 1 to form an electric heat. It is possible to cool the seal member 20 after applying heat to the seal member 20 with a heater or the like to make the bore wall shape. Then
The sealing member 20 is softened by applying heat when the sealing member 20 is molded, so that the sealing member 2
0 can be easily molded into a shape conforming to the bore wall shape.

Further, since the seal member 20 is formed of a resin material, corrosion of the seal member 20 due to adhesion of water, freezing, and the like is prevented as compared with the seal member 20 in which the plastically deformable material is made of a metal material. Can also be planned. further,
The operability of the throttle valve 2 is improved by forming the seal member 20 with, for example, ethylene tetrafluoride resin (PTFE, trade name: Teflon) having a low sliding resistance among the resin materials. The seal member 20 can be formed of a plastically deformable material made of a metal material such as lead or tin which is softer than the bore wall surface 8 of the throttle body 1 instead of the ethylene tetrafluoride resin. Further, the throttle valve 2 can be formed of a resin material such as a nylon resin or a metal material such as lead or tin instead of the ethylene tetrafluoride resin.

Also, since the throttle body 1 is formed of a resin material, the molding dimensions and surface roughness of the bore wall surface 8 are better than those of the throttle body 1 formed of a metal material, and post-processing after molding is omitted. As a result, the manufacturing cost of the throttle body 1 can be reduced. Further, corrosion due to adhesion of water, freezing and the like can be prevented, and the weight can be reduced. The throttle body 1 can be formed of a metal material such as aluminum instead of a resin material.

Further, since the throttle body 1 is formed of a resin material and the plastically deformable material is a sealing member 20 made of a resin material, freezing between the throttle body 1 and the throttle valve 2 during a cold time is prevented. Thus, the malfunction of the throttle valve 2 due to the icing can be avoided. Along with this, it is possible to abolish the heating device of the hot water type, the electric heating type, etc., which is provided for preventing icing. Further, by eliminating the heating device, it is possible to reduce the cost, reduce the weight and make the device compact, and also possible to avoid deterioration and corrosion due to heating of the throttle body 1 and the seal member 20.

Second Embodiment A second embodiment will be described with reference to FIGS. The second embodiment is a modification of the first embodiment. FIG. 5 is a cross-sectional view of a peripheral portion of the seal member 20, and FIG. 6 is a partial cross-sectional view showing a state before the seal member 20 is formed. In the present embodiment, in the seal member 20 of the first embodiment, the outer peripheral end portion 203 having a substantially semicircular cross section is used instead of the outer peripheral end portion 201 having a tapered cross section.
And Therefore, when the throttle valve 2 is fully closed, the outer peripheral end portion 203 of the seal member 20 easily slides on the bore wall surface 8 of the throttle body 1, which is effective in preventing the stick of the throttle valve 2.

[Third Embodiment] A third embodiment will be described with reference to FIGS. The third embodiment is a modification of the second embodiment. FIG. 7 is a cross-sectional view of a peripheral portion of the seal member 20, and FIG. 8 is a partial cross-sectional view showing a state before the seal member 20 is formed. In the present embodiment, a radially intermediate portion of the seal member 20 (reference numeral 204 is attached).
Are formed thinner than the inner and outer ends. For this reason, the intermediate part 204 of the seal member 20 is easily deformed, and the seal member 20 having a good shape, that is, a good formability can be obtained.

[Fourth Embodiment] A fourth embodiment will be described with reference to FIG. Embodiment 4 is Embodiment 1
Is a partial change. FIG. 9 is a partial sectional view showing a state before the sealing member 20 is formed. In this embodiment, the bore wall surface 8 of the throttle body 1
The lip 90 is integrally formed in the bore upstream direction (upward in the figure). For this reason, moisture or the like that is going to collect on the contact surface between the bore wall surface 8 and the lip 90 is guided by the lip 90 toward the inner peripheral side of the lip 90 (reference numeral 901) and accumulates. Therefore, moisture hardly accumulates on the contact surface between the bore wall surface 8 and the lip 90, which is effective in preventing malfunction of the throttle valve 2 due to icing.

[Fifth Embodiment] A fifth embodiment will be described with reference to FIG. 10 and FIG. Embodiment 5
Is a modification of the first embodiment. FIG. 10 is a sectional view of the throttle valve assembly according to FIG. 2, and FIG. 11 is a sectional view of a peripheral portion of the seal member 20. In this embodiment, a concave groove 281 that is not sealed to the outer peripheral portion of the seal member 20 is used.
And a vent portion 28 penetrating through the front and back surfaces of the throttle valve 2 by the groove portion 281. For this reason,
When the throttle valve 2 is fully closed, a constant amount of air can flow from the ventilation section 28. Further, since the ventilation portion 28 is provided on the outer peripheral portion of the seal member 20, it is possible to prevent the accumulation of moisture between the seal member 20 and the bore wall surface 8 of the throttle body 1. As a result, it is effective in preventing icing and preventing inflow foreign matter from being caught. Also,
Since the amount of material corresponding to the ventilation portion 28 of the seal member 20 can be reduced, the material cost of the seal member 20 can be reduced.
The vent portion 28 only needs to penetrate the front and back surfaces of the seal member 20, and can be formed by a through hole penetrating the seal member 20, a slit dividing the seal member 20 in the radial direction, or the like. .

Sixth Embodiment A sixth embodiment will be described with reference to FIG. The sixth embodiment is a modification of the first embodiment. FIG. 12 is a cross-sectional view of the throttle valve assembly according to FIG. 2, with the valve main plate partially cut away. In this embodiment, the seal member 20 is provided intermittently in the circumferential direction of the throttle valve 2. In FIG. 12, the seal member 20 is provided in a predetermined range at the open / close end of the throttle valve 2. Therefore, when the throttle valve 2 is fully closed, the gap between the seal members 20 (reference numeral 2,
9 is attached. ) Can flow a constant amount of air. Further, similarly to the fifth embodiment, it is possible to prevent the accumulation of moisture between the seal member 20 and the bore wall surface 8 of the throttle body 1, and to reduce the material cost of the seal member 20.

[Seventh Embodiment] A seventh embodiment will be described with reference to FIG. The seventh embodiment is a modification of the first embodiment. FIG. 13 shows the seal member 2
FIG. 2 is a cross-sectional view of a peripheral portion of FIG. In this embodiment, the sealing member 2
0 is thicker than the thickness of the valve main plate 25.
The outer peripheral end portion 206 of the seal member 20 is tapered.

The present invention is not limited to the above embodiment, but can be modified without departing from the scope of the present invention. For example, the entire throttle valve 2 can be set as the seal member 20. Further, for the seal member 20, it is also possible to use a material that is shaped by applying heat or the like instead of a material that is shaped at room temperature.

[0043]

According to the present invention, the clearance between the outer peripheral surface of the valve and the bore wall surface of the body can be reduced, and the processing cost and the assembly cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a throttle valve assembly according to a first embodiment.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view of a peripheral portion of a seal member.

FIG. 4 is a partial sectional view showing a state before the sealing member is formed.

FIG. 5 is a sectional view of a peripheral portion of a seal member according to the second embodiment.

FIG. 6 is a partial sectional view showing a state before the sealing member is formed.

FIG. 7 is a sectional view of a peripheral portion of a seal member according to a third embodiment.

FIG. 8 is a partial sectional view showing a state before the sealing member is formed.

FIG. 9 is a partial sectional view showing a state before molding of a seal member according to a fourth embodiment.

FIG. 10 is a sectional view showing a throttle valve assembly according to a fifth embodiment in accordance with FIG. 2;

FIG. 11 is a sectional view of a peripheral portion of a seal member.

FIG. 12 is a sectional view showing a throttle valve assembly according to a sixth embodiment in accordance with FIG. 2;

FIG. 13 is a sectional view of a peripheral portion of a seal member according to a seventh embodiment.

FIG. 14 is a front sectional view of a throttle valve assembly showing a conventional example.

FIG. 15 is a right side view of the same.

FIG. 16 is a side sectional view of the same.

FIG. 17 is a front sectional view of a throttle valve assembly showing another conventional example.

FIG. 18 is a partial sectional view showing another example of the conventional slot valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throttle body (body) 2 Throttle valve (valve) 3 Throttle valve shaft (valve shaft) 8 Bore wall surface 10 Bore 20 Seal member (Seal part) 28 Vent part

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[Procedure amendment]

[Submission date] October 13, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

[0012]

According to the first aspect of the present invention, there is provided a body for forming a bore through which air flows.
A throttle valve assembly comprising: a valve shaft rotatably provided on the body; and a plate-shaped valve attached to the valve shaft and opening and closing the bore by rotation. And a seal member formed in contact with the bore wall surface, wherein the seal member is formed of a plastically deformable material softer than the bore wall surface. According to the throttle valve assembly of claim 1, after assembling the valve to the body,
By closing the valve to the fully closed position, the seal member comes into contact with and is shaped by the bore wall surface of the body, so that the outer peripheral surface of the valve conforming to the bore wall shape can be easily obtained with high precision. Thereby, the gap between the outer peripheral surface of the valve and the bore wall surface of the body can be reduced, and the processing cost and the assembly cost can be reduced.

Claims (8)

[Claims] A body forming a bore through which air flows;
A throttle valve assembly comprising: a valve shaft rotatably provided on the body; and a plate-shaped valve attached to the valve shaft and opening and closing the bore by rotation. A throttle member assembly having a seal member formed so as to be capable of contacting the bore wall surface, wherein the seal member is formed of a plastically deformable material softer than the bore wall surface. 2. The throttle valve assembly according to claim 1, wherein a position opened by a predetermined opening from the fully closed position of the valve is set to an idle opening after shaping of the seal member. Valve assembly. 3. The throttle valve assembly according to claim 1, wherein the seal member is provided with a ventilation portion penetrating the front and back surfaces thereof. 4. The throttle valve assembly according to claim 1, wherein the seal member is provided intermittently in a circumferential direction of the valve. 5. A method for manufacturing a throttle valve assembly according to claim 1, wherein the sealing member is bored in the body by closing the valve after assembling the valve to the body. A method for manufacturing a throttle valve assembly, comprising: applying heat to a seal member to form a bore wall shape when contacting the wall surface to form the seal member; and cooling the seal member. 6. The throttle valve assembly according to claim 1, wherein the plastically deformable material is made of a resin material. 7. The throttle valve assembly according to claim 1, wherein the body is formed of a resin material. 8. The throttle valve assembly according to claim 7, wherein the plastically deformable material is made of a resin material.