JP2005351191A - Idling air amount adjusting device in throttle body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control an idling air amount accurately, uniformly and stably; and to easily adjust the idling air amount. <P>SOLUTION: Air intake passages 11a, 11b on upstream/downstream sides of a throttle valve 13 are communicated through a bypass passage B. Opening/closing of an opening area of the bypass passage B is controlled by a starting valve 14 placed in a starting valve guide cylinder 1 connected to the bypass passage B. A start adjusting rod 6 is engaged with and disposed in a throttle body 10 along the longitudinal axis X-X of the starting valve 14, and a tip part 6a of the start adjusting rod 6 is arranged facing to a lower end 14a of the starting valve 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel injection device that supplies fuel boosted by a fuel pump to an engine via a fuel injection valve and controls the amount of air directed to the engine by a throttle valve disposed in a throttle body, and in particular, idling operation of the engine. The present invention relates to an idle air amount adjusting device in a throttle body that controls an idling air amount at the time and a starting air amount at the time of starting operation of an engine.

An idle air amount adjusting device in a conventional throttle body is shown in FIG.
Referring to FIG. 2, reference numeral 10 denotes a throttle body having an intake passage 11 penetrating therethrough, and the opening area of the intake passage 11 is adjusted to a throttle valve shaft 12 rotatably supported by the throttle body 10. Open / close control is performed by a throttle valve 13 to be worn.
B is a bypass air passage formed by bypassing the throttle valve 13, and its upstream side opens to the intake passage 11 a upstream of the throttle valve 13, and its downstream side is an intake passage downstream of the throttle valve 13. Open to 11b. The opening area of the bypass air passage is controlled by the start valve 14.
The start valve is movably disposed in a start valve guide tube 15 connected upward from the bypass air passage B. The upper portion of the start valve guide tube 15 has a female screw hole 15a and an upper end 15b. An opening is formed.
Reference numeral 16 denotes a closing member that is screwed into the female screw hole 15a of the start valve guide cylinder 15 and closes the upper opening of the start valve guide cylinder 15. The closing member 16 has an adjustment female screw hole 16a formed upward. Further, an adjustment screw 17 is screwed into the adjustment female screw hole 16a.
Reference numeral 18 denotes a start wire for opening and closing the start valve 14, one end of which is locked to the upper portion of the start valve 14 with an end 18a, and the other end is locked to an operation member such as an operation lever (not shown).
The starting wire 18 is inserted and arranged in the flexible tube 19, and the end 19 a of the flexible tube 19 is disposed in contact with the locking step 17 a in the adjustment screw 17.
That is, the starter wire 18 inserted and arranged in the flexible tube 19 is connected to the starter valve 14 by the end 18a from the end 19a of the flexible tube 19 through the adjustment screw 17, the closing member 16, and the starter valve guide tube 15. Locked.

According to such a conventional idle air amount adjusting device, the minimum idling air amount of the engine is adjusted as follows.
The throttle valve 13 is held slightly opened from the fully closed state.
This is a minute opening that does not allow the throttle valve 13 to bite into the intake passage 11, and the idling air amount is not yet guaranteed by the opening of the throttle valve 13.
Next, the adjusting screw 17 is screwed and the adjusting screw 17 is displaced upward to raise the starting wire 18 in synchronization with the upward movement of the adjusting screw 17, thereby moving the starting valve 14 upward and bypass air passage. Hold B open for a certain amount.
According to the above, the idling supplied toward the engine by the total air amount of the air amount obtained by the minute opening of the throttle valve 13 and the air amount flowing through the bypass air passage B when the start valve 14 is opened. The amount of air is controlled.
Then, with the idling air amount set, the nut 20 screwed on the outer periphery of the adjustment screw 17 is pressed and screwed toward the upper end 16b of the closing member 16, thereby fixing the position of the adjustment screw 17. Thereafter, the idling air amount is guaranteed.

  On the other hand, at the time of starting the engine at a low temperature or the like, the starting operation wire 18 is pulled when increasing the amount of starting air toward the engine. According to this, the starting valve 14 has a spring force of the starting valve spring 21. To increase the opening of the bypass air passage B, thereby increasing the amount of air flowing from the bypass air passage B into the intake passage 11b on the downstream side, thereby obtaining the desired starting air. it can.

Here, according to such a conventional idle air amount adjusting device, the adjustment of the air amount during idling is performed by screwing the adjusting screw 17 and displacing the starting wire 18 together with the flexible tube 19 to increase the opening degree of the starting valve 14. According to this, since the displacement of the adjusting screw 17 cannot be directly applied to the start valve 14, it is difficult to adjust the minute opening of the start valve 14.
Further, after adjusting the adjustment screw 17, it is necessary to tighten the nut 20 to fix the adjustment screw 17. According to this, the adjustment screw 17 is slightly moved in the axial direction due to backlash of the screw portion of the adjustment screw 17. There is a possibility that the amount of idling air varies.
Furthermore, the necessity of the nut tightening operation cannot shorten the adjustment operation time.

  The present invention has been made in view of the above problems, and provides an idle air amount adjusting device in a throttle body capable of accurately and uniformly controlling an idling air amount and easily adjusting an idling air amount. The first purpose.

An idle air amount adjusting device for a throttle body according to the present invention is made in view of the above-mentioned problems. An intake passage is formed through the inside of the throttle body, and an opening area of the intake passage is controlled to be opened and closed by a throttle valve. An intake passage upstream of the throttle valve and an intake passage downstream of the throttle valve are connected by a bypass air passage, and the bypass air passage is opened and closed by a start valve operated by a start wire. In
A first feature is that a start adjusting rod for adjusting the minimum opening of the start valve is screwed to the throttle body along the longitudinal axis of the start valve and facing the lower end of the start valve.

In addition to the first feature, the present invention provides a start adjustment rod guide hole for screwing and supporting the start adjustment rod,
The second feature is that the outer periphery of the start adjusting rod is hermetically held by a seal ring.

Furthermore, in addition to the second feature, the present invention provides a seal ring storage hole having a larger diameter than the start adjustment rod guide hole at the outer opening end of the start adjustment rod guide hole.
On the other hand, the start adjustment rod is provided with a coil spring having one end locked to the start adjustment rod and the other end locked to a washer that is loosely fitted to the start adjustment rod.
A third feature is that the seal ring disposed in the seal ring housing hole is pressed by a washer that receives the spring force of the coil spring.

According to the first feature of the present invention, the start adjusting rod is disposed along the longitudinal axis of the start valve, and the tip of the start adjusting rod is disposed opposite the lower end of the start valve.
Therefore, the start valve can be moved and adjusted in the longitudinal axis direction in the start valve guide cylinder by screwing the start adjusting rod, and the amount of idling air from the bypass air passage to the intake passage downstream of the throttle valve can be adjusted. .
At the time of such adjustment, the start valve can be moved directly in the longitudinal axis direction without passing through other members, so that the idling air amount by the start valve can be controlled extremely accurately and uniformly. it can.
In addition, since no external force such as nut tightening is applied to the start adjustment rod after the start adjustment rod is adjusted, the start adjustment rod is not displaced after the start adjustment rod is adjusted. Can be controlled.
Furthermore, the operation of adjusting the nut can be efficiently performed by simply screwing the start adjusting rod and the operation of tightening the nut is unnecessary.
Furthermore, since the start valve guide tube and the start adjustment rod guide hole are formed along the longitudinal axis of the start valve, the workability of the start valve guide tube and the start adjustment rod guide hole can be improved.

  Further, according to the second feature of the present invention, since the seal ring is disposed between the start adjustment rod guide hole and the outer periphery of the start adjustment rod, the air flow from the start adjustment rod guide hole into the start valve guide cylinder Can be completely shut off, so that an accurate and uniform idling air amount controlled only by the start valve can be obtained.

Furthermore, according to the third feature of the present invention, the seal ring disposed in the seal ring storage hole is pressed by a washer that receives the spring force of the coil spring, so that the seal ring is elastically deformed and held in the seal ring storage hole. Thus, the air flowing from the outer periphery of the start adjustment guide guide hole and the start adjustment guide rod into the start valve guide tube can be completely blocked.
At this time, since the seal ring is disposed in the seal ring storage hole formed by opening at the opening end of the start adjusting rod guide hole, the seal ring can be mounted in the seal ring storage hole very easily and the mounting performance is improved. it can.
Further, the washer receives the spring force of the coil spring and always presses it toward the seal ring, so that the seal ring can be elastically deformed reliably and stably in the seal ring housing hole, and the sealing effect of the seal ring can be improved. .
Furthermore, according to the second and third features, it is possible to reliably prevent the entry of foreign matters such as water, mud and the like from the start valve adjusting rod guide hole into the start valve guide cylinder, and in particular, the dynamic characteristics of the start valve are increased. Maintains well over time.

An embodiment of an idle air amount adjusting device for a throttle body according to the present invention will be described below with reference to FIG.
2 that are the same as those in FIG.
Reference numeral 1 denotes a start valve guide tube continuously provided upward from the bypass air passage B. The upper end of the start valve guide tube opens upward with a female screw hole 1a, and the bypass air passage 14 opens on the side wall of the start valve guide tube 1. To do. A start valve 14 for controlling the opening of the bypass air passage B is movably disposed in the start valve guide cylinder 1.
Reference numeral 2 denotes a closing member that is screwed into the female screw hole 1 a of the start valve guide cylinder 1, and a through hole 2 a is formed in the closing member 2 along the longitudinal axis XX of the start valve 14.
Reference numeral 19 denotes a flexible tube in which the starting wire 18 is inserted and arranged, and the end 19a of the flexible tube 19 is locked to the locking step 2b of the through hole 2a.
The starting wire 18 disposed in the flexible tube 19 is inserted from the flexible tube 19 into the starting valve guide cylinder 1 through the through hole 2a, and an end 18a provided at the end of the starting wire 18 is disposed in the starting valve 14. It is locked to the upper end of.
Reference numeral 21 denotes a start valve spring that presses the start valve 14 downward in the drawing.
Reference numeral 3 denotes a start adjusting rod guide hole formed substantially concentric with the longitudinal axis XX of the start valve 14, and its upper end opens at the bottom 1c of the start valve guide tube 1, and its lower end is a start adjusting rod boss. 4 is formed to open at the lower end 4a.
An annular seal ring storage hole 3b having a larger diameter than the start adjustment rod guide hole 3 is formed at the outer opening end portion 3a of the start adjustment rod guide hole 3 that opens to the lower end 4a of the start adjustment rod boss 4. The
A seal ring 5 made of an elastic material made of an O ring, a square ring, or the like is inserted and disposed in the seal ring storage hole 3b.
Reference numeral 6 denotes a start adjustment rod that is screwed into the start adjustment rod guide hole 3, and its front end portion 6 a passes through the bottom portion 1 b of the start valve guide tube and is in contact with the lower end 14 a of the start valve 14. A knob portion 6c is formed on the portion 6b.
7 is a coil spring disposed on the outer periphery 6d of the start adjusting rod 6. One end 7a of the coil spring is locked to the step portion 6e of the knob portion 6c, and the other end 7b is loosely fitted on the outer periphery 6d of the start adjusting rod 6. Locked to the disposed washer 8.
According to the above, the washer 8 is pressed upward in the figure by the spring force of the coil spring 7. According to this, the seal ring 5 disposed in the seal ring housing hole 3b is pressed upward in the figure by the washer 8. The upper portion of the seal ring 5 is pressed against the upper bottom portion 3c of the seal ring housing hole 3b, and the lower portion of the seal ring 5 is pressed against the upper surface of the washer 8 in the drawing.

Next, the operation will be described.
First, the engine idling air amount is adjusted as follows.
The throttle valve 13 is held slightly opened from the fully closed state.
Next, the knob portion 6c of the start adjusting rod 6 is screwed to move and adjust the start adjusting rod 6 upward.
According to this, the tip 6a of the start adjusting rod 6 contacts the lower end 14a of the start valve 14 and pushes the start valve 14 upward, whereby the opening of the bypass air passage 14 is controlled and the throttle valve 13 is controlled from the bypass air passage B. The amount of air toward the intake passage 11b on the downstream side is controlled.
Thus, the idling air amount is determined by the total air amount of the air amount controlled by the throttle valve 13 and the air amount supplied from the bypass air passage B.
Since the amount of air flowing through the bypass air passage B can be finely adjusted by screwing the start adjusting rod 6, a desired idling air amount can be supplied.

Here, in particular, the start adjusting rod 6 is disposed along the longitudinal axis XX of the start valve 14 and the tip portion 6a of the start adjusting rod 6 is disposed in direct contact with the lower end 14a of the start valve 14. Since the movement of the start adjusting rod 6 and the start valve 14 can be moved synchronously, the opening of the bypass air passage B can be finely controlled, so that an accurate and uniform idling air amount can be adjusted and controlled.
Further, since the screw adjustment only needs to be performed by the operation of the start adjusting rod 6, there is no influence of other members and the idling air amount does not vary or change after the adjustment.
Also, according to the above, since no other members are operated, the adjustment work can be simplified.
Further, the axial movement of the start valve 14 can be made fine by reducing the screw pitch of the male screw formed in the start adjusting rod 6, whereby the amount of air flowing in the bypass air passage B can be finely adjusted.

  Note that, at the time of starting the engine at a low temperature or the like, when the amount of start air toward the engine is increased, the start operation wire 18 is towed. Accordingly, the opening of the bypass air passage B is increased, whereby the amount of air flowing from the bypass air passage B into the intake passage 11b on the downstream side can be increased, and thus desired starting air can be obtained. .

Further, according to the present invention, the seal ring 5 is disposed between the start adjustment rod guide hole 3 and the start adjustment rod 6, so that air outside the throttle body 10 is started from the start adjustment rod guide hole 3. Since it does not flow into the valve guide cylinder 1 and the bypass air passage B, accurate and stable idling air can be supplied.
Further, according to the above, since dust, water, etc. in the atmosphere do not flow into the bypass air passage B from the start adjusting rod guide hole 3 in the same manner, stable control of the bypass air by the start valve 14 is performed. Can do.

Further, a seal ring storage hole 3b is formed in the outer opening end 3a of the start adjustment guide guide hole 3 that opens to the lower end 4a of the start adjustment base boss 4, and the seal ring 5 is disposed in the seal ring storage hole 3b. According to this, it is possible to greatly improve the mountability of the seal ring 5 as compared with those arranged on the inner periphery of the start adjustment rod guide hole 3 or those arranged on the outer periphery of the start adjustment rod 6.
Furthermore, according to the fact that the seal ring 5 disposed in the seal ring housing hole 3b is pressed and supported by the washer 8 backed up by the spring force of the coil spring 7, the seal ring 5 is placed in the seal ring housing hole 3b. The elastic deformation can be ensured, and the air flow from the start adjusting rod guide hole 3 into the start valve guide tube 1 can be completely blocked.

  As in this proposal, the start adjustment rod boss 4 is formed on the throttle body 10 along the longitudinal axis XX of the start valve 14, and the start adjustment rod guide hole 3 is formed to provide the start adjustment rod 6. The arrangement of can be very easily changed with respect to the conventional throttle body 10 and has wide applicability.

The longitudinal cross-sectional view which shows one Example of the idle air quantity adjusting device in the throttle body of this invention. The longitudinal cross-sectional view of the idle air quantity adjusting device in the conventional throttle body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Start valve guide cylinder 3 Start adjustment rod guide hole 3a Outward opening end 3b Seal ring accommodation hole 5 Seal ring 6 Start adjustment rod 7 Coil spring 8 Washer 10 Throttle body 14 Start valve B Bypass air passage

Claims (3)

An intake passage is formed through the inside, and an opening area of the intake passage is controlled to be opened and closed by a throttle valve, and an intake passage upstream from the throttle valve and an intake passage downstream from the throttle valve are bypass air passages. Further, in the throttle body, the bypass air passage is controlled to be opened and closed by a start valve operated by a start wire.
A start adjustment rod 6 that adjusts the minimum opening of the start valve 14 along the longitudinal axis XX of the start valve and faces the lower end 14a of the start valve 14 is screwed to the throttle body 10. Device for adjusting the amount of idle air in the throttle body. A start adjustment rod guide hole 3 for screwing and supporting the start adjustment rod;
The idle air amount adjusting device for a throttle body according to claim 1, wherein the outer periphery 6d of the start adjusting rod 6 is hermetically held by the seal ring 5. A seal ring housing hole 3b having a larger diameter than the start adjustment rod guide hole 3 is provided at the outer opening end 3a of the start adjustment rod guide hole;
On the other hand, the start adjustment rod 6 includes a coil spring 7 whose one end 7a is locked to the start adjustment rod 6 and whose other end 7b is locked to a washer 8 that is loosely disposed on the start adjustment rod 6.
The idle air amount adjusting device for a throttle body according to claim 2, wherein the seal ring (5) disposed in the seal ring housing hole (3b) is pressed by a washer (8) that receives the spring force of the coil spring (7).

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