JPH0452380B2 - - Google Patents

Description

Detailed Description of the Invention The present invention relates to a plate-shaped sliding throttle valve arranged in an intake passage communicating with an engine to reduce suction resistance in the intake passage when the throttle valve is fully opened. The present invention relates to a throttle body device that can significantly reduce the sliding frictional resistance of a sliding throttle valve by arranging a bearing in the sliding portion of the throttle body.

To explain the conventional sliding throttle valve device (for example,
It is disclosed in Japanese Utility Model Application Publication No. 55-25647. ) A sliding throttle valve 3 for controlling opening and closing of the intake passage is disposed near a fuel port that injects fuel into an intake passage 2 that penetrates the carburetor body 1 and communicates with the engine. Flange portions 7a, 7b extending along the sliding direction protrude from the outer diameter of the carburetor body, and guide grooves 9a, 9b extending in the sliding direction are arranged in the carburetor body in correspondence with the flanges.
A linear motion bearing 10 is provided between the flange of the sliding throttle valve and the guide groove of the carburetor body to allow the sliding throttle valve to open and close.
a and 10b were arranged in a sandwiched manner. In this case, since the sliding throttle valve and the carburetor body sandwich a "moving linear motion bearing" and are in contact with each other at two points on the outer diameter of the bearing, the contact friction force cannot be effectively reduced, and the sliding This may cause a shift in the relative position of the dynamic throttle valve to the carburetor body, and there is a risk that the linear motion bearing may fall off.In addition, the use of linear motion bearings may increase the price of the carburetor due to the larger sliding parts. There were some drawbacks such as: Furthermore, the side surface of the flange opposite to the surface on which the linear motion bearing is placed is in direct contact and sliding contact with the carburetor body, making it impossible to reduce the contact friction force.

The present invention has been made in view of the above, and an object of the present invention is to increase the sliding frictional force of the sliding throttle valve in a plate-shaped sliding throttle valve in which a bearing is disposed on the sliding part. By reducing the width, the sliding load on the sliding throttle valve is reduced, reliably eliminating the stick, ensuring safe operation, and allowing the adoption of a plate-shaped sliding throttle valve for larger diameter intake passages. It is an object of the present invention to provide a throttle body device with high suction efficiency as engine output increases.

The present invention is particularly applicable to an electronically controlled fuel injection system of the so-called speed density method (intake pressure detection method), which does not place obstacles such as air flow sensors in the intake path that cause intake resistance. Although engine control with high suction efficiency can be achieved, the design is not limited to the embodiment and can be modified.

One embodiment of the present invention will be described with reference to FIGS. 1 to 6. A throttle body 1 that forms an intake passage 2 that communicates with an intake port 8 that is opened and closed by an intake valve 7 of an engine 6 has vertical sliding parts. A plate-shaped sliding throttle valve 3 is arranged to be movable, and a radial ball bearing 4 that rolls in the sliding direction is mounted on the sliding portion of the sliding throttle valve. Since the throttle body 1 is provided with a sliding groove 5 whose width is slightly larger (gap δ) than the outside diameter of the radial ball bearing, the outside diameter of the radial ball bearing is adjusted by the clearance δ. It is possible to make contact with the sliding groove at one point x (that is, contact only with the sliding surface on one side of the sliding groove). Fifth
As is clear from the figure, the synthetic resin coating 9 is thick on the surface where the sliding throttle valve makes sliding contact with the throttle body (over both sides or only one side of the engine-side surface and the intake-side surface of the plate-shaped throttle valve). The height is set so that the outer diameter of the radial ball bearing and the plate thickness of the sliding throttle valve are approximately the same dimension. The synthetic resin coating includes a synthetic resin filled with tetrafluoroethylene resin (Teflon resin) or difluoride molybdenum, and the thickness of the sliding throttle valve containing the coating is the same as that of the original radial ball bearing. It may be set larger than the outer diameter so that the outer diameter of the radial ball bearing and the plate thickness of the sliding throttle valve become substantially the same through break-in operation. Furthermore, a rail member 10 made of stainless steel is embedded in the rolling surface of the throttle body that comes into contact with the radial ball bearing when the sliding throttle valve slides. Note that 11 indicates a missing circular portion for passing idle air, and arrow B indicates the direction of intake air flow.

A first link 13 rotatably connected to a link hole 12 of the sliding throttle valve is connected to a second link fixed to a shaft 14 rotatably supported by the throttle body.
It is connected to the link 15 by a rotation pin 16. The shaft 14 is driven by a throttle grip (not shown) or a pulse motor (not shown), and the amount of rotation of the shaft is electrically detected by a throttle opening sensor 17. The throttle body has a pressure sensor 18 that detects the pressure in the intake passage.
and injector 1 that injects fuel into the intake passage.
9 is arranged, and the engine speed sensor 2
0. A microcomputer 22 is arranged to control the opening and closing of the injector 19 based on electrical signals input from the intake air temperature sensor 21, the throttle opening sensor 17, and the pressure sensor 18. Incidentally, the fuel supplied to the injector 19 is pressurized from the fuel tank 23 by the fuel pump 24 and is then supplied to the accumulator 25 and the regulator 2.
6, the fuel pressure is adjusted to a constant level.

To explain the operation, when the shaft 14 is rotated with the throttle grip to open the sliding throttle valve 3, the pressure signal in the intake passage detected by the pressure sensor 18 and other electrical signals are A control signal is input to the computer 22 and outputted to the injector 19 to inject the optimum amount of fuel calculated by the microcomputer, thereby supplying fuel into the intake passage. When the sliding throttle valve is fully open, there are no obstructions in the intake passage communicating with the engine (there are no chimney-shaped throttle valves, air flow sensors, etc.), and the maximum output of the engine can be improved.

In particular, in the present invention, the outer diameter of the radial ball bearing rolls into contact with the sliding surface of the sliding groove at one point on the outer diameter, so there is no sliding frictional resistance at all, and the fluid force due to intake air is transferred to the plate-like aperture. Even when applied to the valve, the sliding frictional resistance does not increase, ensuring stable operation of the sliding throttle valve and achieving bore up. In the past, the fluid force caused by the intake air accompanying the bobber up greatly acted on the sliding throttle valve, increasing the sliding resistance and causing sticking, but the present invention has solved this problem.

In addition, since a synthetic resin coating is formed on the sliding surface of the sliding throttle valve so that the outer diameter of the radial ball bearing and the plate thickness of the sliding throttle valve are approximately the same dimension, the gap δ can be set extremely small. It is possible to prevent the flow of air from the gap into the intake passage, thereby ensuring airtightness and stabilizing the mixture ratio especially during low-speed operation. Furthermore,
Further, by forming the synthetic resin film, it becomes easier to control the machining accuracy of the gap size δ and the surface roughness, and it is possible to provide a throttle body device that is easy to produce and is inexpensive.

Furthermore, since a stainless steel rail is embedded in the rolling surface of the throttle body that comes into contact with the radial ball bearing, sliding durability is further improved.

As described above, the present invention achieves reduction and stabilization of the sliding load of the sliding throttle valve by greatly reducing the sliding friction force of the sliding throttle valve, thereby eliminating the stagnation and ensuring safe operation. This throttle body device can greatly contribute to increasing the diameter of the intake passage and improving engine output.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing one embodiment of the throttle body device of the present invention, FIG. 2 is a partial sectional view taken from A in FIG. 1, and FIG. 3 is a partial sectional view taken from C-C in FIG. A sectional view of the sliding throttle valve, Figure 4 is a left side view of the sliding throttle valve seen from the left side of Figure 3, Figure 5 is a partially enlarged view of Figure 1, and Figure 6 is D of Figure 5. - It is a partial sectional view seen from D. 1...Throttle body, 2...Intake path, 3...
...Sliding throttle valve, 4...Radial ball bearing, 5...Sliding groove.

Claims (1)

[Claims] 1. A plate-shaped sliding throttle valve 3 that controls the opening and closing of the intake passage 2 that passes through the throttle body 1 and communicates with the engine.
and a bearing disposed on the sliding part of the sliding throttle valve, in which the sliding throttle valve 3 is equipped with a radial ball bearing 4 that rolls in the sliding direction, and the outer diameter dimension of the radial ball bearing is A throttle body device characterized in that a sliding groove 5 having a slightly larger width is arranged in the throttle body, and the outer diameter of a radial ball bearing is brought into contact at one point with the sliding surface of the sliding groove. 2. Claim 1, wherein a synthetic resin coating is formed on the sliding surface of the sliding throttle valve so that the outer diameter of the radial ball bearing and the plate thickness of the sliding throttle valve are approximately the same dimension. Throttle body device. 3. The throttle body device according to claim 1, wherein the rolling surface of the throttle body that contacts the outer diameter of the radial ball bearing is made of stainless steel. 4. The throttle body device according to claim 1, wherein the throttle body forms an intake passage of an electronically controlled fuel injection device whose fuel injection amount is calculated based on at least the pressure within the intake passage.