JPH0717942U - Sliding valve carburetor - Google Patents

Abstract

(57) [Summary] [Purpose] To easily manufacture a highly reliable sliding valve carburetor. [Structure] The vaporizer main body 11 is integrally formed by casting. The support member 30 is fitted into the vaporizer main body 11. A roller bearing 33 that reduces sliding resistance is provided on the roller support portion 31 of the support member 30. Lubricating resin is applied to the surface of the annular portion 32 of the support portion 30 on the sliding valve 13 side, and processing is performed so as to obtain a minute gap with the sliding valve 13.
A seal ring 30 is provided on the back side of the annular portion 32 so as to be in pressure contact with the carburetor main body 11 to enhance airtightness. The sliding valve 13 only contacts the roller bearing 33, and the roller bearing 33 allows the sliding valve 13 to move smoothly up and down.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sliding valve type carburetor provided in a motorcycle or the like.

[0002]

[Prior art]

 Conventionally, an intake passage for allowing air taken in from the outside through an air funnel or the like to flow inside the carburetor body of a sliding valve carburetor, and a valve communicating with this intake passage at a predetermined angle. A chamber is formed, and a sliding valve slides in the valve chamber to move into and out of the intake passage, thereby changing the flow passage area of the intake passage. However, this sliding valve type carburetor has the drawback that the sliding resistance increases and the opening / closing operation of the sliding valve becomes abnormally heavy because the sliding valve type carburetor is attracted to the engine side during high negative pressure during deceleration. There is. In order to reduce this sliding resistance, a sliding valve type carburetor has been proposed in which a valve chamber or sliding valve is provided with rollers or bearings.

[0003]

[Problems to be solved by the device]

 However, these carburetors are provided with rollers and bearings by dividing the main body, and it is necessary to provide a seal member in order to ensure the airtightness of the divided parts, which makes the structure complicated and also in terms of cost. Not an advantage.

The present invention has been made in view of the above problems, and an object thereof is to obtain a sliding valve type carburetor that is easy to manufacture and has high reliability.

[0005]

[Means for Solving the Problems]

 A sliding valve type carburetor according to the present invention includes a carburetor body having an intake passage, a sliding valve for changing a flow passage area of the intake passage, and a sliding valve fitted to the carburetor body. And a support member having a plurality of roller bearings in contact with.

[0006]

【Example】

 The present invention will be described below with reference to illustrated embodiments. FIG. 1 is a sectional view showing the construction of a sliding valve type carburetor which is an embodiment of the present invention.

In FIG. 1, an intake passage 12 is formed inside the carburetor main body 11 along an axis A. The intake passage 12 is provided with a slide valve 13 that can move up and down in a direction orthogonal to the axis A. The slide valve 13 is slidably supported in a valve chamber 14 formed in the carburetor body 11, and is displaced in the vertical direction in FIG. 1 to change the flow passage area of the intake passage 12. A jet needle 20 is fixed to the sliding valve 13. The jet needle 20 extends below the carburetor main body 11 and is inserted into the fuel passage 17. A float chamber 15 is arranged below the sliding valve 13. The fuel stored in the float chamber 15 is guided to the fuel passage 17 in the needle jet 19 through the main jet 16, is atomized by the air flowing in from the air jet 18, and is supplied to the intake passage 12. The flow rate of the fuel guided from the fuel passage 17 to the intake passage 12 is adjusted by the insertion degree of the jet needle 20.

A throttle shaft 21, which is interlocked with a throttle lever (not shown), is rotatably supported on the upper portion of the carburetor main body 11, and a connecting lever 22 is fixed to the throttle shaft 21 and is swingable about the throttle shaft 21. Has been done. The connecting lever 22 is connected to the slide valve 13 via a link 23, and the swing of the connecting lever 22 causes the slide valve 13 to move up and down in the valve chamber 14. A cover 24 is attached to the upper portion of the portion that houses the throttle shaft 21 and the connecting lever 22.

Air is taken into the intake passage 12 through the air funnel 25 formed in a trumpet shape, mixed with the fuel guided from the fuel passage 17, and supplied to an engine (not shown). The flow rate of air passing through the intake passage 12 is adjusted by the vertical movement of the slide valve 13.

FIG. 2 is a sectional view of the carburetor main body 11 taken along the axis A in the horizontal direction, FIG. 3 is a sectional view taken along the line III-III of FIG. 1, and FIG. FIG. 5 is a perspective view showing a member 30.

As shown in these drawings, the carburetor main body 11 is provided with a support member 30 on the downstream side of the sliding valve 13 (on the opposite side of the air funnel 25). As shown in FIG. 4, the supporting member 30 has a pair of roller supporting portions 31 and an annular portion 32, and each roller supporting portion 31 is provided on both sides of the annular portion 32. The roller support portion 31 is formed in a U-shape when viewed from above, and has an outer plate portion 31a, an inner plate portion 31b, and a back plate portion 31c connecting them. A plurality of roller bearings 33 are provided vertically between the outer plate portion 31a and the inner plate portion 31b, and are rotatably supported by pins 34 attached to the outer plate portion 31a and the inner plate portion 31b. There is. All the roller bearings 33 are arranged on the same plane so as to come into contact with the sliding valve 13. The arrangement surface of the roller bearings 33 protrudes toward the sliding valve 13 side from the inner plate portion 31b, and the outer plate portion 31a protrudes toward the sliding valve 13 side from the arrangement surface of the roller bearings 33. The roller bearing 33 is formed of, for example, a synthetic resin material in order to reduce noise.

The annular portion 32 has a bore 35, and a lubricating resin 36 is applied to the surface of the annular portion 32 on the sliding valve 13 side. A groove 38 is provided on the downstream surface of the annular portion 32, and a seal ring 37 is arranged in the groove 38. The seal ring 37 adheres to the carburetor main body 11 while keeping airtightness, thereby preventing air from leaking. The support member 30 is attached to the inside of the carburetor main body 11 such that the bore 35 is arranged at a position matching the intake passage 12.

As shown in FIG. 2, two bulged portions 26 projecting in opposite directions are formed on the carburetor main body 11 downstream of the slide valve 13. The roller support portion 31 of the support member 30 is fitted into the bulging portion 26.

The sliding valve 13 is formed in a hollow box shape, and the plate portion on the downstream side of the sliding valve 13 has two protruding portions 13a. Each projecting portion 13 a projects toward the outer plate portion 31 a and is in contact with the roller bearing 33. The slide valve 13 faces the surface of the annular portion 32 coated with the lubricating resin 36 with a minute gap. That is, the sliding valve 13 normally contacts only the roller bearing 33.

The operation of the apparatus of this embodiment will be described. The fuel supplied from the fuel passage 17 to the intake passage 12 is mixed with the air taken in from the outside via the air funnel 25, is guided in the downstream direction of the intake passage 12, and is supplied to an engine (not shown). The flow rate of fuel supplied to the engine is adjusted by the vertical movement of the jet needle 20 attached to the slide valve 13, and the flow rate of air is adjusted by the vertical movement of the slide valve 13. The sliding valve 13 is sucked toward the engine side by the engine negative pressure, and thereby comes into contact with the roller bearing 33 installed on the support member 30 and thus smoothly moves up and down. Here, even if the sliding valve 13 bends due to engine negative pressure or the like and comes into contact with the support member 30, the sliding resin 13 does not exert a large frictional resistance due to the action of the lubricating resin 36.

The manufacturing process of the device of this embodiment will be described. The carburetor main body 11 is integrally formed by casting, and the inner wall surface is cut if necessary.

The support member 30 is manufactured in a separate process from the vaporizer main body 11, for example, by casting. Lubricating resin 36 is applied to the surface of the annular portion 32 of the support member 30 on the sliding valve 13 side, and then a small clearance is formed between the sliding valve 13 and the roller bearing 33 as a reference. Is ground. A groove 38 is formed on the back surface of the annular portion 32, and a seal ring 37 is fitted in the groove 38. Then, the support member 30 is inserted from above the carburetor main body 11 and is fastened and fixed by screws (not shown). Then, the slide valve 13 is inserted into the valve chamber 14.

As described above, according to the present embodiment, since the vaporizer main body 11 is integrally formed by casting, the structure is simpler and easier to manufacture than the conventional vaporizer in which the main body is divided. To be done. In addition, the cost is relatively low because a seal member for ensuring the airtightness of the divided parts is not required. Further, since the support member 30 is manufactured in a process different from that of the carburetor main body 11, the work of mounting the roller bearing 33 and the work of grinding the lubricating resin 36 are easy, and therefore, the working accuracy is easy to secure and reliable. It is highly Further, there has been a conventional one in which the sliding valve is of a split type in order to secure the sealing property, but this is not necessary in the present embodiment, so that the number of parts can be reduced.

[Effect of device]

 As described above, according to the present invention, a sliding valve type carburetor that is easy to manufacture and highly reliable can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a vaporizer according to an embodiment of the present invention.

2 is a cross-sectional view of the vaporizer main body of FIG. 1 taken along the axis A. FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a perspective view of a support member according to an embodiment of the present invention.

[Explanation of symbols]

 11 Vaporizer body 12 Intake passage 13 Sliding valve 30 Support member 33 Roller bearing 35 Bore 36 Lubricating resin

Claims (2)

[Scope of utility model registration request] 1. A carburetor main body having an intake passage, a slide valve for changing a flow passage area of the intake passage, and a plurality of roller bearings fitted into the carburetor main body and contacting the slide valve. And a supporting member having the sliding valve type carburetor. 2. The support member is provided with a bore forming a part of an intake passage, and a lubricating resin is applied to a sliding surface on the outer circumference of the bore, and the sliding surface is based on an array surface of roller bearings. The sliding valve type carburetor according to claim 1, characterized in that it is processed substantially in the same plane.