JPS603330Y2 - carburetor idle adjustment device - Google Patents

Description

[Detailed description of the invention] This invention uses a carburetor idle adjustment device, especially to prevent an increase in harmful engine exhaust gas components caused by a general automobile user turning the carburetor idle adjustment screw. The present invention relates to a device that does this.

In recent years, harmful exhaust gas components from engines have become increasingly regulated in order to prevent pollution, and not only do harmful exhaust gas components fall below the regulated values during engine manufacturing, but they also have to be maintained at a certain regulated value even after the engine is put into use. It is requested that the amount not be exceeded.

In particular, the adjustment of the idle adjustment screw on the carburetor is directly related to the air-fuel ratio of the mixture supplied to the engine, so complete adjustment of this idle adjustment screw is necessary to minimize harmful exhaust gas components. When manufactured at the factory, the idle adjustment screw is perfectly adjusted to keep harmful exhaust gas components below regulated values.

However, if this screw is easy for general users to turn, they will easily turn the idle adjustment screw when the engine is malfunctioning, resulting in an increase in harmful exhaust gas components. It turns out.

Therefore, after the idle adjustment screw is adjusted at the factory so that the harmful exhaust gas components are below the regulation value, the idle adjustment screw must be locked so that general users cannot turn it without permission. It has become necessary to install a mechanism, and various idle adjustment devices have been proposed to meet this demand.

However, conventional idle adjustment devices for carburetors each have their own advantages and disadvantages; for example, the locking mechanism for making the idle adjustment screw unrotatable is easily destroyed and cannot serve the purpose of locking; Those that made it difficult to destroy had drawbacks such as the need to replace the entire carburetor if it became necessary to urgently adjust the idle adjustment screw.

゛This invention provides an idle adjustment device in which it is difficult for a general user to destroy the locking mechanism, and which does not require replacement of the carburetor body when the idle adjustment screw needs to be adjusted urgently. It is something.

Examples of this invention will be described below with reference to the drawings.

In FIG. 1, a carburetor body 1 includes a venturi body 2.
and a throttle body 3, which are connected with bolts 4.

In addition, 5 is a gasket interposed between the joint surfaces of the bodies 2 and 3, 2a is a venturi, 3a is a throat port, and 3b
is an idle port, and 6 is a throttle valve.

An idle adjustment screw 7 is screwed into the throttle body 3, and the upper half of the idle adjustment screw 7 is exposed to the outside of the throttle body 3, and this exposed portion is covered with a cylindrical cap 8.

The cap 8 is made of an aluminum die-cast product, and has a stepped portion 9a on the lower end side of the through hole 9, a ring-shaped i9b on the upper end side, and two parallel protrusions 10, 10 on the outer surface. By protruding the protrusion 1
A groove-shaped recess 10a is formed between 0 and 10, and the recess 1
A closing portion 10b is integrally provided at the upper end of 0a.

Then, insert the concave portion 10a of the cap 8 into the venturi body 2.
The rotation of the cap 8 about the idle adjustment screw 7 is restricted by fitting into the convex portion 2b protruding from the through hole 9 (see FIG. 3), and the step 9a in the through hole 9 and the idle adjustment screw 7 The cap 8 is attached to the throttle body 3 by compressing a spring 11 between the cap 8 and the head 7a, and screwing the idle adjustment screw 7 into the throttle body 3 against the elasticity of the spring 11.

Further, in the groove 9b of the through hole 9 of the cap 8, as shown in FIG. 12 is installed.

Furthermore, a blind plug 13 made of high-hardness hardened steel and having a spherical head 13a and a cutout groove 13b cut on the outer periphery is inserted into the upper end of the through hole 9 of the cap 8. 13b is the elastic claw 12 of the stopper 12.
b is engaged and the blind plug 13 cannot be detached.

In the above structure, the idle adjustment screw 7 with the cap 8 attached is screwed into the throttle body 3 to an appropriate length,
When the blind plug 13 is attached to the cap 8 after adjusting the harmful exhaust gas components to be below the regulation value, the idle adjustment screw 7 is completely covered by the cap 8 and the blind plug 13, so that a general user can remove the idle adjustment screw. 7 cannot be rotated.

In addition, a spring 11 is placed between the stepped portion 9a provided at the lower part of the through hole 9 of the cap 8 and the head 7a of the idle adjustment screw 7.
Since the cap 8 is compressed, removal of the cap 8 is prevented.

Further, even if the user turns the cap 8 and attempts to turn the idle adjustment screw 7 by frictional force via the spring 11, the concave portion 10a of the cap 8 is fitted into the convex portion 2b of the venturi body 2, so the cap 8 and idle adjustment screw 7 are not rotated.

Further, in the above embodiment, the blind plug 13 has a high hardness, for example, hardness.

Since it is made of hardened steel of 60 or more and has a spherical head 13a, it is possible to grasp the head 13a with pliers etc. in order to pull out the blind plug 13.
It is impossible to destroy it with a drill or the like, and since the elastic pawl 12b of the stopper 12 is engaged with the notch groove 13b of the blind plug 13, the blind plug 13 cannot be pulled out, and therefore the idle adjustment cannot be performed. Unable to turn screw 7.

Furthermore, in the embodiment described above, the end of the protrusion 2b of the venturi body 2 is covered with the closing part 10b at the upper end of the recess 10a of the cap 8, so that general users do not feel like cutting off the protrusion 2b. At the same time, even if a general user attempts to remove it, it becomes extremely difficult to do so.

On the other hand, if readjustment of the idle adjustment screw 7 becomes unavoidable due to engine failure, etc., loosen the bolt 4, remove the throttle body 3 from the venturi body 2, and remove the concave portion 10a of the cap 8 and the convex portion of the venturi body 2. disengaging from the portion 2b, then pulling the cap 8 upward and rotating the cap 8 while compressing the spring 11,
The stepped portion 9a and the idle adjustment screw 7 are connected via the spring 11.
The idle adjustment screw 7 is
The idle adjustment screw 7 integrated with the cap 8 described above can be removed from the throttle body 3 by rotating, and then a new separately prepared idle adjustment screw 7, cap 8, etc. can be attached.

Note that it is not possible to separate the idle adjustment screw 7 and cap 8 that have been removed in the combined state, so a general user should remove the idle adjustment screw 7 and cap 8 as described above and then reinstall the same ones. It cannot be readjusted.

This invention is not limited to the above embodiments,
Various modifications are possible.

For example, instead of protruding the protrusions 10 and 1G, the recess 10a of the cap 8 may be formed by enlarging the outer diameter of the cap 8 and cutting the outer surface thereof. A recess may be provided in the throttle body 3 for engagement.

As explained above, this invention consists of a carburetor body formed by removably connecting a throttle body to a venturi body, an idle adjustment screw screwed onto the throttle body and partially exposed, and the idle adjustment screw. a cap having a through hole surrounding the exposed portion of the cap and an engaging means for engaging the venturi body to restrict rotation around the idle adjustment screw; a spring that is compressed between the formed step and the head of the idle adjustment screw to make the cap non-removable from the carburetor body; and a blind plug that is non-removably fixed to the other end of the through hole of the cap. Therefore, after the idle adjustment screw has been adjusted at the factory, it is impossible for general users to turn the idle adjustment screw without permission, and as a result, harmful exhaust gas components may exceed the regulation value. It will never be surpassed.

If adjustment of the idle adjustment screw becomes unavoidable, the throttle body can be separated and the idle adjustment screw or cap can be replaced and readjusted.

Moreover, the carburetor main body, which consists of the venturi body and the throttle body, can be reused as is, so there is little waste.

[Brief explanation of drawings]

FIG. 1 is a vertical front view of an embodiment of this invention, FIG. 2 is an enlarged sectional view of the stopper, and FIG. 3 is a sectional view taken along the line mm in FIG. 1. 1: Carburetor body, 2: Venturi body, 3: Throttle body, 7: Idle adjustment screw, 7a: Head, 8: Cap, 9: Through hole, 9a: Step, 9a: Groove, 10a:
Recess (retaining means), 11 spring, 12 stopper, 13 blind plug.

Claims (1)

[Claims for Utility Model Registration] 1. A carburetor body formed by detachably coupling a throttle body to a venturi body, an idle adjustment screw screwed onto the throttle body and partially exposed, and the idle adjustment screw. A cap having a through hole surrounding the exposed portion and having an engaging means that engages with the venturi body to restrict rotation around the idle adjustment screw; and a cap formed at one end of the through hole of the cap. a spring that is compressed between the stepped portion and the head of the idle adjustment screw and makes it impossible to remove the cap from the carburetor body; and a blind plug that is non-removably fixed to the other end of the through hole of the cap. A carburetor idle adjustment device comprising: 2 Utility model registration claim No. 1 in which the blind plug is made of high-hardness steel and has a spherical head.
The idle adjustment device for the carburetor as described in Section 1. 3 A notch groove is cut on the outer periphery of the blind plug, and a ring-shaped groove is formed in the through hole of the cap.
The vaporizer according to claim 1, wherein a stopper having a plurality of elastic claws projecting inward is mounted, and the elastic claws of the stopper are engaged with the notch grooves of the blind plug. equipment idle adjustment device. 4. The utility model registration claim set forth in claim 1, wherein the retaining means for regulating rotation of the cap comprises a convex portion provided on the venturi body and a concave portion provided on the outer periphery of the cap and fitted into the convex portion. Carburetor idle adjustment device.