JPS6339402Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a float valve device for a carburetor, in particular, a float whose base is pivotally supported by a substantially horizontal support shaft in a float chamber, and a float that extends in a plane perpendicular to the support shaft. a valve shaft whose lower end is locked to the base of the float and has a valve body at its upper end, and a valve shaft which surrounds the lower part of the valve shaft and is interposed between the valve shaft and the base The present invention relates to a float valve device for a carburetor, including a coil spring that urges the valve body upward.

Conventionally, in such a float valve device, as shown in FIGS. 1 and 2, the base 25 of the float 6 is
A locking hole 37 that can be engaged with a locking portion 35 provided at the lower end of the valve shaft 27 is formed in the valve shaft 27, and a guide notch 44 that is connected to the locking hole 37 is further provided. When locking the valve stem 27 to the base 25, the valve stem 27 is guided at an angle so that the lower end of the coil spring 28 rests on the end of the base 25, as shown by arrow 45. It must be inserted into the locking hole 37 through the notch 44, and it must be installed with care so that the end of the base 25 is not pinched between the pitches of the coil spring 28. It was complicated and hot.

The present invention was developed to eliminate such conventional drawbacks, and it simplifies the structure for attaching the valve stem to the base of the float and facilitates the installation work, as well as accurately controlling the set state after installation. The purpose of the present invention is to provide a float valve device for a carburetor, which is capable of holding a float, and its features include a float whose base is pivoted by a substantially horizontal support shaft in a float chamber, and a float whose base is pivoted within a float chamber by a substantially horizontal support shaft, and a a valve shaft whose lower end is locked to the base of the float and has a valve body at its upper end, allowing slight relative rocking with respect to the float; A float valve device for a carburetor including a coil spring interposed between the base and urging the valve body upward,
The lower part of the valve shaft is provided with a small-diameter shaft part surrounded by the coil spring, and a disc-shaped locking part that projects radially outward at the lower end of the shaft part, and the base part is provided with a small-diameter shaft part surrounded by the coil spring. An insertion hole that allows insertion of the locking portion and prevents insertion of the coil spring, a locking hole that only allows insertion of the small diameter shaft portion, and a width that allows only insertion of the small diameter shaft portion. A guide hole communicating between the insertion hole and the locking hole is bored, and a circular spring receiving recess into which the lower end of the coil spring is loosely fitted is formed on the upper surface of the base of the float. It is to be drilled concentrically with the stop hole.

Hereinafter, an embodiment of the present invention will be explained with reference to the drawings. First, in FIG. A cylindrical float chamber body 3 with a bottom is attached to the float chamber body 3 via a sealing member 4, and a float chamber 5 is defined by the carburetor main body 1 and the float chamber body 3. There is a float 6 in the float chamber 5.
The float valve device 7 opens and closes in response to the float 6, which floats up and down depending on fuel consumption, so that the fuel oil level l in the float chamber 5 is always maintained at a substantially constant level.

A bench lily 8 is provided in the middle of the intake path 2, and a chiyoke valve 10 is installed in the carburetor main body 1 on the upstream side of the bench lily 8 along the intake direction shown by an arrow 9.
is pivotally supported, and a throttle valve 11 is pivotally supported on the carburetor main body 1 on the downstream side of the bench lily 8.

A cylindrical holder 12 extending downward is integrally provided at the lower part of the carburetor body 1 at a position corresponding to the bench lily 8, and a female thread 13 is cut into the lower end of this holder 12. On the other hand, float chamber body 3
A through hole 14 is bored in the center of the bottom of the carburetor main body 1 and the float chamber body 3 by screwing a bolt 15 passing through the through hole 14 from below into the female thread 13 and tightening it. are integrally combined. In order to prevent fuel from leaking from the through hole 14, a seal member 16 is interposed between the head of the bolt 15 and the bottom of the float chamber body 3.

The holder 12 includes a fuel nozzle 17 facing the bench lily 8 of the intake passage 2, and a bleed pipe 19 that is integrally and concentrically connected to the fuel nozzle 17 and forms an annular chamber 18 between it and the inner surface of the holder 12. is inserted. The annular chamber 18 is communicated with the upstream end of the intake passage 2 via a bleed passage (not shown). Additionally, a fuel jet 20 is connected to the lower end of the bleed pipe 19.
A suction chamber 22 is defined within the bolt 12 between the fuel jet 20 and the tip of the bolt 15. Further, in the side wall of the holder 12, a communication hole 23 is provided that communicates the inside of the suction chamber 22 and the float chamber 5.
is drilled.

The float valve device 7 includes a float 6 whose base 25 is pivotally supported by a horizontal support shaft 24 within the float chamber 5.
and a valve shaft 27 whose lower end is locked to the base 25 to allow slight relative rocking with respect to the float 6 in a plane perpendicular to the support shaft 24 and which has a valve body 26 at its upper end.
and a coil spring 28 that surrounds the lower part of the valve shaft 27 and is interposed between the valve shaft 27 and the base 25 to bias the valve body 26 upward.

The carburetor main body 1 is provided with a fuel supply passage 29 for guiding fuel into the float chamber 5.
A fuel inlet 30 communicating with the fuel supply path 29 and facing downward at the upper part of the float chamber 5 is provided. Further, a guide cylinder portion 31 having a larger diameter than the fuel inlet 30 is provided integrally with the carburetor body 1 so as to extend downward and concentrically with the inlet 30 .

Referring also to FIG. 4, the valve shaft 27 is composed of a large diameter shaft portion 32 and a small diameter shaft portion 33 that are concentrically and integrally connected in order from above.
A conically shaped valve body 26 is integrally connected to the upper end of the fuel inlet 30 so as to be seated on the opening edge of the fuel inlet 30 . Further, on the outer surface of the large diameter shaft portion 32, a plurality of protrusions 34 extending in the axial direction are protruded at intervals in the circumferential direction, and these protrusions 34 are in sliding contact with the inner surface of the guide cylinder portion 31. , forming a fuel passage between them. Further, each protrusion 34 is provided with enough room to fit the end of the coil spring 28 into the lower part of the large diameter shaft portion 32, and the end of each protrusion 34 is provided at the lower part of the large diameter shaft portion 32. support the department. Further, at the lower end of the small-diameter shaft portion 33, a disc-shaped locking portion 35 having a diameter comparable to that of the large-diameter shaft portion 32 and extending outward in the radial direction is provided.
is provided.

Referring also to FIG. 5, the base 2 of the float 6
5 includes an insertion hole 36 that allows insertion of the locking portion 35 and prevents insertion of the coil spring 28, and a locking hole 37 that only allows insertion of the small diameter shaft portion 33;
A guide hole 38 having a width that allows only the insertion of the small diameter shaft portion 33 and communicating the insertion hole 36 and the locking hole 37 is formed in a straight line perpendicular to the axis of the support shaft 24. That is, the outer diameter of the locking portion 35 is d1, the outer diameter of the coil spring 28 is d2, and the insertion hole 3 is
Assuming that the diameter of the shaft 6 is d3, the diameter of the locking hole 37 is d4, the outer diameter of the small diameter shaft portion 33 is d5, and the width of the guide hole 38 is d6, their size relationship is set as follows.

d1<d3<d2...(1) d1>d4...(2) d4>d6>d5...(3) The outer diameter d of the coil spring 28 is provided on the upper surface of the base 25.
A circular spring receiving recess 39 having a diameter larger than 2 is bored concentrically with the locking hole 37 . Also,
It has semicircular parts at both ends that have the same radius as the locking hole 37 and are concentric with the locking hole 37 and the insertion hole 36, and the oval-shaped depression 40 formed by communicating these semicircular parts is the spring receiver. It has a shallower depth than the recess 39 and is bored in the upper surface of the base 25 . Furthermore, a notch 41 that slightly extends on the opposite side of the guide hole 38 with respect to the locking hole 37 has the same width as the guide hole 38 and has the same width as the guide hole 38 .
5.

Next, to explain the operation of this embodiment, when attaching the valve stem 27 to the base 25 of the float 6, as shown by the two-dot chain line in FIG. 35. At this time, the lower end of the coil spring 28 is received by the recess 40. Next, the guide hole 3 of the small diameter shaft portion 33
8 to the locking hole 37, the locking portion 3
5 has a larger diameter than the locking hole 37, so the base 25
The lower end of the coil spring 28 is loosely fitted into the spring receiving recess 39. This prevents the valve stem 27 from easily returning to the guide hole 38 side, and maintains the position of the valve stem 27.

With the float valve device 7 attached to the carburetor,
The vertical movement of the float 6 is transmitted to the valve shaft 27 via the coil spring 28, and the valve body 26 responds to the float 6.
opens and closes the fuel inlet 30. Moreover, since the vibration of the float 6 is absorbed by the coil spring 28, the fuel inlet 30 will not open or close unnecessarily due to the vibration of the float 6, and when the valve is closed, the valve body 28 will not open or close unnecessarily.
6 is the fuel inlet 3 due to the spring force of the coil spring 28.
The valve is pressed against the opening edge of 0, and the closed state is reliably maintained.

In addition, the insertion hole 36, the locking hole 37, and the guide hole 3
8 is arranged on a straight line perpendicular to the support shaft 24, and a notch 41 is provided on the straight line.
Relative rocking of the valve shaft 26 and the base 25 shown at 3 is allowed freely.

As described above, according to the present invention, the lower part of the valve stem is provided with a small-diameter shaft portion surrounded by a coil spring, and a locking portion that extends radially outward at the lower end of the shaft portion, and the locking portion extends outward in the radial direction. The base has an insertion hole that allows the locking part to pass through and prevents the coil spring from passing through, a locking hole that only allows the small diameter shaft part to pass through, and a width that allows only the small diameter shaft part to pass through. Since a guide hole is drilled to communicate the insertion hole and the locking hole with a After compressing and deforming the coil spring and inserting it into the insertion hole from above, all you have to do is move it horizontally along the guide hole to the locking hole. Can be installed on.

Further, on the upper surface of the base of the float, a circular spring receiving recess into which the lower end of the coil spring is loosely fitted is formed concentrically with the locking hole, so that the valve shaft can be inserted through the guide hole as described above. When horizontally moved to the locking hole, the lower end of the coil spring automatically falls into the spring receiving recess on the upper surface of the float base, thereby reliably regulating the horizontal movement of the coil spring and, by extension, the valve stem. Therefore, it is not only possible to prevent the valve stem from moving toward the insertion hole through the guide hole and detaching from the float base, but also to hold the valve stem in a fixed position on the float base to ensure that the float valve is always properly operated. can be activated. In addition, the upper surface of the float base has an extremely simple configuration in which the spring receiving recess is simply formed, so that the position of the valve stem can be regulated.For this purpose, a movement regulating member is specially provided to face the guide hole. Since there is no need to do this, it can contribute to reducing costs and improving ease of assembly.

[Brief explanation of the drawing]

Figures 1 and 2 show the prior art;
Fig. 1 is a plan view of the main part, Fig. 2 is a sectional view taken along the line - - in Fig. 1, Figs. 4 is an enlarged vertical sectional view of the main part of FIG. 3, and FIG. 5 is a plan view of FIG. 4. 5... Float chamber, 6... Float, 7... Float valve device, 24... Support shaft, 25... Base, 2
6...Valve body, 27...Valve stem, 28...Coil spring, 33...Small diameter shaft portion, 35...Locking portion, 36...
...Insertion hole, 37...Latching hole, 38...Guide hole, 3
9... Spring receiving recess.

Claims (1)

[Scope of utility model registration request] A float 6 whose base portion 25 is pivotally supported by a substantially horizontal support shaft 24 in the float chamber 5, and the support shaft 24
A valve shaft 2 whose lower end is locked to the base of the float 6 to allow slight relative rocking with respect to the float 6 in a plane perpendicular to , and has a valve body 26 at its upper end.
7; and a coil spring 28 which surrounds the lower part of the valve shaft 27 and is interposed between the valve shaft 27 and the base 25 and urges the valve body 26 upward. At the bottom of the valve stem 27,
A small diameter shaft portion 33 surrounded by the coil spring 28
and a disc-shaped locking portion 35 that extends outward in the radial direction at the lower end of the shaft portion 33. Insertion hole 36 that prevents insertion
and a locking hole 37 that only allows the small diameter shaft portion 33 to be inserted therethrough, and a locking hole 37 that has a width that allows only the insertion of the small diameter shaft portion 33 and communicates between the insertion hole 36 and the locking hole 37. A guide hole 38 is bored in the upper surface of the base 25 of the float 6, and a circular spring receiving recess 3 into which the lower end of the coil spring 28 is loosely fitted is formed.
9 is formed concentrically with the locking hole 37.