JPH0378537A - Hot water heating device of throttle body - Google Patents

Abstract

PURPOSE:To prevent a throttle body from its abnormal high temperature by providing a valve means, which is open-close driven in accordance with a predetermined heating temperature, in a hot water path, in the case of a carburetor in which the throttle body is heated by hot water of passing through the hot water path formed in the throttle body. CONSTITUTION:In a carburetor of an engine, a throttle valve 11 is rotatably supported in a throttle body main unit 1, and a valve shaft 12 of the throttle valve 11 is turned through an electromagnetic clutch mechanism 40 by actuating a motor 50 while through an accelerator link mechanism 30 in accordance with operation of an accelerator pedal. The body main unit 1 is heated by hot water introduced from an inlet pipe line 4 to an annular hot water path 2 formed around an intake passage 1a. Here a valve means 9 for opening and closing the hot water path 2 is provided, and a shape memory alloy-made spring 8, serving as a driving member, is interposed between this valve means 9 and a stepped part 4a, formed in an end face of the inlet pipe line 4, with the valve means 9 urged in a closing direction when a temperature of hot water is increased to not less than a predetermined value.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hot water heating device for a throttle body, and more particularly to a hot water heating device that can limit the heating temperature for the throttle body to a predetermined temperature.

[Prior Art] In recent years, internal combustion engines have been equipped with a throttle body equipped with a throttle valve, a throttle sensor, etc., as electronically controlled fuel injection devices have been adopted. This throttle body controls the amount of intake air to the internal combustion engine, and unlike a carburetor that mixes fuel and air, it only controls the amount of air.

By the way, in a carburetor, a sudden temperature drop may occur due to the heat of vaporization of gasoline fuel, and the throttle valve or the like may freeze, so various heating devices are installed to prevent this. On the other hand, in the throttle body, the temperature does not decrease due to the heat of vaporization, but in harsh environments, moisture adhering to the throttle valve and the like may freeze and stick. For this reason, a hot water heating device is provided in the throttle body. Specifically, a hot water passage is formed within the throttle body, or a plate with a hot water passage formed is placed close to the throttle body, and the cooling water of the internal combustion engine, that is, the hot water after warming up, flows through these hot water. It is configured to constantly circulate through the road.

[Problems to be Solved by the Invention] However, in the hot water heating device described above, hot water is constantly circulating, so if the temperature near the throttle body becomes abnormally high for some reason, it may have an adverse effect on peripheral equipment. For example, control circuit components for an idle speed control device are attached to the throttle body, and there is a concern that the throttle body may malfunction at abnormally high temperatures. Furthermore, recently, a motor-controlled throttle control device has been proposed, in which a motor and its control device are mounted on a throttle body. For this reason, the temperature in the vicinity of the control device becomes higher due to the heat generated when the motor is driven, so it is desirable to take some measures to prevent abnormally high temperatures.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to perform hot water heating control using a simple means in a hot water heating device for a throttle body so that the vicinity of the throttle body does not become abnormally high temperature.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides hot water heating of the throttle body by providing a hot water channel in the throttle body of an internal combustion engine and heating the throttle body with hot water circulating through the hot water channel. The apparatus includes a valve means for opening and closing the hot water channel, and a driving means for driving the valve means to open and close in accordance with a predetermined heating temperature for the throttle body.

The valve means is a normally open valve device installed in the hot water channel,
The driving means may be a water temperature sensitive driving member that is sensitive to the temperature of the hot water circulating in the hot water channel and drives the valve device to close when the temperature of the hot water reaches a predetermined temperature or higher.

Alternatively, the valve means is a normally open valve device installed in the hot water channel, and the driving means is responsive to the ambient temperature of the throttle body, and when the ambient temperature reaches a predetermined temperature or higher, the valve device is closed. It may also be an outside temperature sensitive driving member.

The valve means includes a valve body that seats on a valve seat provided in the hot water channel and closes the hot water channel, and a spring that biases the valve body in the opening direction, and the biasing force of the spring is normally maintained. Accordingly, the valve body can be configured to be separated from the valve seat.

As the water temperature sensitive drive member, for example, there is a bimetal disposed so as to press against the valve body in the hot water channel, and the temperature characteristics of the bimetal are determined when the temperature of the hot water reaches a predetermined temperature or higher. may be set so that it is seated on the valve seat against the biasing force of the spring.

Further, as the outside temperature sensitive drive member, for example, there is a spring made of a shape memory alloy which is placed in contact with the valve body and exposed to the outside air, and the temperature characteristics of the spring made of the shape memory alloy are adjusted when the outside air reaches a predetermined temperature. The valve body may be set so as to resist the biasing force of the spring and sit on the valve seat when this occurs.

[Operation] In the throttle body heating device configured as described above, the valve means is driven to open and close by the driving means in accordance with a predetermined heating temperature for the throttle body. As a result, the hot water channel opens and closes to control the flow rate of hot water circulating therethrough, and the heating temperature for the throttle body is limited to a predetermined heating temperature or less.

According to a system using a water temperature sensitive drive member and a normally open valve device, the former is sensitive to the temperature of hot water circulating in a hot water channel, and when the hot water reaches a predetermined temperature or higher, the valve device is driven to close, and the throttle is The heating temperature for the body is suppressed to a predetermined temperature.

Further, according to a device using an outside temperature sensitive drive member and a normally open valve device, the former is sensitive to the ambient temperature of the throttle body, and when this temperature reaches a predetermined temperature or higher, the valve device is driven to close. The heating temperature for the throttle body is suppressed to a predetermined temperature.

[Embodiments] Hereinafter, preferred embodiments of the hot water heating device for a throttle body of the present invention will be described with reference to the drawings.

As shown in FIG. 1, a throttle valve 11 is rotatably supported by a throttle shaft 12 within an intake passage 1a of a throttle body body 1 of an internal combustion engine.

Throttle shaft 12 has ball bearings 13.14
It is rotatably supported on both side surfaces of the throttle body main body 1 via. A case portion 1b is provided on the side surface of the throttle body main body 1 on which one end of the throttle shaft 12 is supported.
A case cover 10 is joined to this case portion 1b, and a control chamber 18 is defined by these parts.

The control chamber 18 houses an electromagnetic clutch mechanism 40 and the like that constitute a throttle control device. This electromagnetic clutch mechanism 40 is connected to the motor 50 and is also configured to be directly connected to the accelerator link mechanism 30 under predetermined conditions. In response to the operation of the accelerator link mechanism 30, the motor 50 is driven by a controller (not shown), and the throttle valve 11 is driven to open and close via the electromagnetic clutch mechanism 40.

On the other hand, the throttle shaft 1 on the opposite side to the case portion 1b
A throttle sensor 15 is attached to the side surface of the throttle body main body 1 on which the other end of the throttle body 2 is supported. The throttle sensor 15 has a detector that detects the opening degree of the throttle valve 11, is connected to the throttle shaft 12, and converts the rotational displacement of the throttle shaft 12 into an electrical signal.
For example, an idle switch signal and a throttle opening signal are output to a controller (not shown). Therefore, in an internal combustion engine equipped with an electronically controlled fuel injection device (not shown),
The amount of intake air supplied into the cylinder through the intake passage 1a is adjusted by the throttle valve 11, and the output of the internal combustion engine is adjusted.

An annular warm water passage 2 is formed in the throttle body main body 1 around an intake passage 18. A communication path 3 is formed which communicates with the hot water channel 2 and extends outward in the radial direction, and an inlet pipe line 4 is connected to the front end of the communication path 3 . Similarly, the first
A communication path 5 is formed on the left side of the figure, and an outlet pipe line 6 is connected thereto.

The communication passage 3 is formed in the shape of a stepped cylinder, and a valve body 9 is accommodated in the large diameter hole 3a. Large diameter hole 3a and medium diameter hole 3
A valve seat 3d is formed at the step between the valve body 9 and the valve seat 3d, and when the valve body 9 is seated on the valve seat 3d, the communication passage 3 is closed. A spring 7 is housed in the medium diameter hole 3b, one end of the spring 7 is supported by a stepped portion with the small diameter hole 3c, and the other end is in contact with one end surface of the valve body 9. An inlet conduit 4 is fitted into the open end of the large diameter hole 3a, and a stepped portion 4a is formed on the end surface of the conduit. A spring 8 made of a shape memory alloy is interposed between the step portion 4a and the end face of the valve body 9 as a water temperature sensitive drive member.

In this way, the biasing forces of the spring 7 and the spring 8 are applied to both end surfaces of the valve body 9, respectively, but when the hot water is always below a predetermined temperature, the valve body 9 is biased in the direction away from the valve seat 3d. The biasing force of the spring 7 exceeds the biasing force of the spring 8, and the communication path 3 is in communication. When the hot water reaches a predetermined temperature or higher, the spring 8
The biasing force increases and exceeds the biasing force of the spring 7, and the valve body 9 seats on the valve seat 3d. Note that the predetermined temperature of the hot water at this time is a temperature that is set according to a predetermined heating temperature for the throttle body main body 1 and the like.

To explain the operation of the heating device configured as described above, cooling water for the internal combustion engine, that is, hot water is introduced into the communication passage 3 via the inlet pipe 4. If the temperature of the hot water is below a predetermined temperature, the valve body 9 is separated from the valve seat 3d, and the hot water passes through the communication path 3 and is introduced into the annular hot water channel 2. Here, heat exchange is performed with the throttle body main body 1, and the nearby throttle valve 11 and the like are heated. This prevents the throttle valve 11 from freezing during cold weather. The hot water that has undergone heat exchange is discharged from the outlet pipe 6 via the communication passage 5 and returned to the internal combustion engine. As the hot water circulates in the hot water channel 2 in this manner, the heated state is maintained.

When the temperature of the hot water reaches or exceeds the predetermined temperature, the valve body 9 is driven to sit on the valve seat 3d against the biasing force of the spring 7 due to the increase in the biasing force of the spring 8. is blocked. This prevents high-temperature hot water from flowing into the hot water channel 2, and the heating operation for the throttle body body 1 and the like is stopped. Thereafter, if the temperature of the hot water falls below a predetermined temperature, the valve body 9 is removed from the valve seat 3d and heating with hot water is performed again. Thus, the spring 8 made of a shape memory alloy, which is a water temperature sensitive drive member, prevents the throttle body 1 etc. from becoming abnormally high temperature.

FIG. 2 shows another embodiment of the present invention, in which substantially the same parts as in the embodiment of FIG.
This embodiment is equipped with an outside temperature sensitive drive member according to the present invention in place of the water temperature sensitive drive member of the embodiment shown in FIG.

In FIG. 2, unlike in FIG. 1, the communication passage 3 communicating with the annular hot water passage 2 of the throttle body body 1 is formed with a vertical hole 3g parallel to the intake passage 1a.
An inlet conduit (not shown) similar to that shown in FIG. 1 is connected to the open end of the tube. The communication passage 3 also communicates with a large-diameter horizontal hole 3e that is perpendicular to the vertical hole 3g and opens into the control chamber 18, and extends from the side surface of the vertical hole 3g in the direction of the intake passage 1a. A small diameter hole 3f is formed. Therefore, large diameter hole 3
A step is formed between e and the small diameter hole 3f, and this is the valve seat 3.
Functions as h. An annular seal member 10 is fitted around the open end of the large diameter hole 3e. The valve body 19 is fitted into the inner diameter portion of the seal member 10 and is housed so as to be seated on the valve seat 3h.

On the other hand, an opening 1d is formed in the side wall of the case portion 1b of the throttle body main body 1 defining the control chamber 18, and the cap 16 is fitted into the opening 1d. The cap 16 has a valve body 1
A stopper 17 is formed at a position opposite to 9. This stopper 17 restricts the movement of the valve body 19 to the right in FIG. 2, and also constitutes a support portion for the spring 8 made of a shape memory alloy. That is, a spring 8 is interposed between the inner surface of the cap 16 in the control chamber 18 and one end surface of the valve body 19, and the stopper 1f is fitted into the spring 8. A sprinkler is accommodated in the small diameter hole 3f and is in contact with the other end surface of the valve body 19. The characteristics of the spring 8 are such that when the atmospheric temperature in the control chamber 18 exceeds a predetermined temperature, the biasing force increases and biases the valve body 19 in the seating direction against the biasing force of the spring 7. Set.

According to the heating device of this embodiment, the spring 8 is located within the control chamber 18 and is sensitive to the ambient temperature. That is, when the ambient temperature is below a predetermined temperature, the valve body 19 is positioned as shown by the two-dot chain line in FIG. It is discharged via passage 5 from outlet line 6. On the other hand, when the ambient temperature reaches a predetermined temperature or higher, the urging force of the spring 8 increases and the valve body 19 is driven to be seated on the valve seat 3h. As described above, in this embodiment, since the driving of the valve body 19 is controlled according to the atmospheric temperature in the control chamber 18 in which various parts to be protected are housed, for example, the electromagnetic clutch mechanism in the control chamber 18 is controlled. The spring 8 immediately responds to the temperature rise caused by heat generation when the coil 40 is energized, and appropriate heating control is performed.

In the embodiments shown in FIGS. 1 and 2, the spring 8 made of shape memory alloy is used.
Alternatively, a temperature sensitive drive member made of bimetal or the like may be used.

[Effects of the Invention] Since the present invention is configured as described above, it has the following effects.

That is, according to the hot water heating device for a throttle body of the present invention, the hot water passage is driven to open and close by the simple means of the valve means and the driving means, and the heating temperature for the throttle body is limited to a predetermined heating temperature or less. Abnormal high temperatures in the vicinity can be suppressed. Thus, stable operation is ensured without impairing the functions of the control circuit components mounted on the throttle body.

If a water temperature sensitive drive member is used as the drive means, the heating temperature source can be controlled and good responsiveness can be obtained.

Further, in the case of a drive member that uses an outside temperature sensitive drive member, since it is sensitive to the ambient temperature of the object to be protected, it is possible to deal with the influence of other heat sources.

[Brief explanation of drawings]

1 is a longitudinal sectional view of one embodiment of the hot water heating device for a throttle body of the present invention, and FIG. 2 is a longitudinal sectional view of another embodiment of the hot water heating device for a throttle body of the present invention. 12... Throttle shaft. 18... Control room, 30... Accelerator link mechanism.

Claims (3)

[Claims] (1) A hot water heating device for a throttle body in which a hot water channel is provided in a throttle body of an internal combustion engine and the throttle body is heated by hot water circulating through the hot water channel, including a valve means for opening and closing the hot water channel, and a valve means for opening and closing the hot water channel. A hot water heating device for a throttle body, comprising: a drive means that opens and closes the throttle body in accordance with a predetermined heating temperature for the throttle body. (2) The valve means is a normally open valve device installed in the hot waterway, and the drive means is responsive to the temperature of the hot water circulating in the hot waterway, so that the temperature of the hot water reaches a predetermined temperature or higher. 2. The hot water heating device for a throttle body according to claim 1, further comprising a water temperature sensitive drive member that drives the valve device to close when the valve device is closed. (3) The valve means is a normally open valve device installed in the hot waterway, and the drive means is sensitive to the ambient temperature of the throttle body, and when the ambient temperature becomes a predetermined temperature or higher, the valve device 2. The hot water heating device for a throttle body according to claim 1, wherein the hot water heating device is an outside temperature sensitive drive member for driving the valve to close.