JP2592236B2 - Vaporizer with heating device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a vaporizer having a heating device for preventing icing.

(Related Art) Conventionally, there is a carburetor mounted on a motorcycle configured as follows.

That is, an intake passage extending in the front-rear direction of the vehicle is formed in the carburetor body. A piston whose axis is substantially perpendicular to the carburetor body is slidably provided in the axial direction of the carburetor body, and the sliding allows the lower end of the piston to freely enter and exit the intake passage. A fuel supply port for supplying fuel to the intake passage is formed on an inner bottom surface of the intake passage below the piston.

A starting fuel supply passage is formed in the carburetor body, one end of which is open in the intake passage downstream of the piston and the other end of which is open in the intake passage upstream of the piston. An operation component, which is a starter lever for opening and closing the fuel supply passage, is provided, and the operation component is disposed on one side of the carburetor body in the vehicle width direction.

If the piston slides into and out of the intake passage due to the sliding of the piston, the cross section of the intake passage is enlarged and reduced, and the intake negative pressure in the intake passage fluctuates. Then, fuel is sucked through the fuel supply port into the intake passage in accordance with the fluctuation, the fuel and intake air are mixed in the intake passage, and the air-fuel mixture is supplied to the engine, and To be served.

On the other hand, when the engine is started, if the fuel supply passage is opened by operating the operation component, the fuel is supplied to the intake passage through the fuel supply passage, thereby facilitating the start of the engine.

By the way, when the fuel is sucked through the fuel supply port and the fuel supply passage into the intake passage and mixed with the intake air, a part of the fuel is vaporized. This may cause a so-called icing phenomenon in which the water freezes.

When this phenomenon occurs, and particularly when the sliding contact portion between the carburetor body and the piston freezes, the sliding of the piston is hindered, and the engine malfunctions.

Therefore, a hot water passage is formed in the vaporizer body,
The inlet and outlet of the hot water passage are communicated with a water jacket formed in an engine cylinder via an introduction pipe and a discharge pipe, and hot water can be circulated between the water jacket and the hot water passage. .

As a result, the frozen portion is warmed, and the occurrence of the phenomenon is prevented.

(Problems to be Solved by the Invention) However, in the above-described conventional technology, the hot water passage is provided only corresponding to a part of the sliding contact portion between the carburetor body and the piston. The hot water passage is not provided in the vicinity of the fuel supply port or the fuel supply passage which is the starting point of the occurrence of the generation. For this reason, in the conventional one,
It is not always satisfactory in preventing the occurrence of the icing phenomenon.

Therefore, it is conceivable to provide a hot water passage close to the fuel supply passage.However, in this case, the operating component for opening and closing the fuel supply passage and the introduction and discharge pipes communicating with the hot water passage are close to each other. As a result, the operation of the operation parts is obstructed by the introduction pipe and the pipe, and conversely, the operation of installing the introduction and discharge pipes at the entrance and the exit of the hot water passage is the operation described above. There is a risk of being disturbed by parts.

(Object of the Invention) The present invention has been made in view of the above-mentioned circumstances, and is intended to prevent the icing phenomenon from occurring in the vaporizer.
To ensure that the piston slides more smoothly,
In addition, even in this case, it is an object of the present invention to maintain good operability of the operation parts and to facilitate the work of attaching the pipe parts to the carburetor body.

(Structure of the Invention) The feature of the present invention for achieving the above object is that an intake passage 21 extending in the front-rear direction of the vehicle is formed in the carburetor body 20, and the axis of the intake passage 21 is substantially the same as the carburetor body 20. A vertical piston 22 is slidably provided in the axial direction thereof, so that the lower end of the piston 22 is allowed to protrude and retract into the intake passage 21 by this sliding. Main nozzles (fuel supply ports) 27 and 37 for supplying fuel to the intake passage 21 are formed, and one end 39 is opened in the intake passage 21 downstream of the piston 22 and the intake passage upstream of the piston 22. A starter fuel supply passage 40 having an open end 38 at the other end 21 is formed in the carburetor body 20, and a starter lever (operating component) 35 for opening and closing the fuel supply passage 40 is provided.
The starter lever (operating component) 35 is disposed on one side of the carburetor body 20 in the vehicle width direction. On the other hand, a hot water passage 51 is formed in the carburetor body 20.
An inlet 52 is formed at one end of the hot water passage 51 in the longitudinal direction, and an outlet 53 is formed at the other end.The cylinder 52 of the engine 12 is connected to the inlet 52 and the outlet 53 through an introduction pipe 54 and a discharge pipe 55.
In a motorcycle which communicates with a water jacket 43 formed in the water jacket 43 so that hot water can be circulated between the water jacket 43 and the hot water passage 51, the carburetor body 20 and the piston 22 can be viewed from the side of the vehicle.
At least a part of the fuel supply passage 40 and the hot water passage 51 are overlapped with each other, and the lower part of the hot water passage 51 is connected to the main nozzles (fuel supply ports) 27 and 37 at the same time. In the vicinity, and in the vertical direction,
The hot water passage 51 extends along substantially the entire sliding contact portion between the carburetor body 20 and the piston 22, and the carburetor body on the opposite side of the starter lever (operation part) 35 in the vehicle width direction. On the other side of 20, the inlet 52 and outlet 53 of the hot water passage 51 and the introduction pipe 54
And the discharge pipe 55 is provided.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 2, reference numeral 1 denotes a motorcycle, and a front wheel 4 and a handle 5 are supported at a front end of a vehicle body frame 2 via a front fork 3. On the other hand, a rear wheel 8 is supported at a rear portion of the vehicle body frame 2 via a rear arm 7. An engine 12 is supported between the main frame 9 of the body frame 2 and the down tube 10.
Drives the rear wheel 8. Further, a fuel tank 13 is supported on the main frame 9 above the engine 12, and a seat 14 is disposed behind the fuel tank 13.

The engine 12 has a crankcase 15 and a cylinder 16 protruding upward from the crankcase 15, and the exhaust gas of the cylinder 16 is supplied to an exhaust port formed at the front of the cylinder 16. An exhaust pipe 17 to be discharged is connected. An intake pipe 18 is connected to an intake port formed at the rear of the cylinder 16, and gasoline from the fuel tank 13 is atomized into air into the intake pipe 18 to form an air-fuel mixture M. A vaporized gas 19 to be supplied into 16 is connected.

The carburetor 19 will be described with reference to FIGS. 1, 3, and 4. FIG.

The carburetor 19 is of a variable venturi type, and an intake passage having a circular cross section is provided in a carburetor body 20 provided on the carburetor.
The intake passage 21 extends in the front-rear direction of the motorcycle 1. A piston 22 having a substantially vertical axis is provided slidably in the axial direction with respect to the carburetor body 20, and the sliding of the piston 22 allows the lower end of the piston 22 to be able to protrude and retract into the intake passage 21. ing.

A main nozzle 27 and a pilot port 37 which are fuel supply ports for supplying fuel (gasoline) to the intake passage 21 are formed on the inner bottom surface of the intake passage 21 below the piston 22.

A venturi portion 24 is formed by the inner peripheral surface of the intake passage 21 and the protruding end of the piston 22. Then, the piston 22 is urged by a spring 25 in a direction protruding into the intake passage 21.

On the other hand, a float chamber 26 is provided below the vaporizer 19, and the venturi section 24 and the float chamber 26 are communicated by a main nozzle 27. The float chamber 26 is configured to store a predetermined amount of gasoline supplied from the fuel tank 13 by fuel supply means (not shown).

The protruding end of the piston 22 has a tapered needle.
The tapered needle 28 is fitted into the main nozzle 27 so as to be movable in the axial direction. On the other hand, the other end of the piston 22 is connected via a wire means 30 to an operating device (not shown) provided on the handle 5.

When the operation device is operated, the piston 22 opens and closes the intake passage 21 by the operation of the operation device and the spring 25. Then, by this, the engine 12
The amount of intake air (illustrated by the arrow A in FIG. 4) is adjusted, and the taper needle 28 adjusts the opening degree of the main nozzle 27. With these adjustments, gasoline corresponding to the amount of intake air A is supplied to the main air inlet. The air is mixed with the air from 31 and supplied into the intake passage 21. The air-fuel mixture M is drawn into the cylinder 16 from the intake pipe 18 and burns, whereby the engine 12 is driven.

A throttle adjust screw 33, an air adjust screw 34, and a starter lever 35, which are operation components, are provided on a left side portion 20a of the carburetor body 20 in the vehicle width direction, which is one side portion of the carburetor body 20.

The throttle adjustment screw 33 is used for the engine 12
Is to adjust the number of revolutions during idling. The air adjustment screw 34 adjusts the amount of air flowing from the pilot air inlet 36 into the pilot port 37. When the engine 12 is idling or the engine 12 is rotating at low speed, the air from the pilot air inlet 36 Fuel from the chamber 26 is mixed in the pilot port 37 and supplied to the intake passage 21.

A starting fuel supply passage 40 is formed in the carburetor body 20 above the intake passage 21. One end 39 of the fuel supply passage 40 is open to the intake passage 21 downstream of the piston 22, and the other end 38 is open to the suction passage 21 upstream of the piston 22. The starter lever 35 is provided so as to open and close a middle portion in the longitudinal direction on the other end 38 side of the fuel supply passage 40.

When the engine 12 is started, the starter lever 35 is operated to open the fuel supply passage 40. Then, the fuel supplied from the float chamber 26 to the fuel supply passage 40 and the air taken into the fuel supply passage 40 from one end 39 of the fuel supply passage 40 are mixed and supplied into the intake passage 21. Is done.

Referring mainly to FIG. 3, a cooling device 41 is provided for cooling the cylinder 16 which is heated by the combustion of the air-fuel mixture M. The cooling device 41 is a water-cooled type and has a radiator 42, and the radiator 42 is attached to the front of the engine 12 and above the down tube 10. On the other hand, a water jacket 43 is formed in the cylinder 16.
A water pump 44 is provided at the lower part of the crankcase 15.
The water pump 44 is linked to the engine 12. The discharge port of the water pump 44 communicates with the water jacket 43 via a joint pipe 45, and the water jacket 43 communicates with the upper part of the radiator 42 via a first hose 47. The lower part of the radiator 42 is connected to the suction port of the water pump 44 by a second hose.
Communicates through 48.

And, with the driving of the engine 12, the water pump
When the 44 is driven, the cooling water C is supplied to the water pump 44 → the joint pipe 45 → the water jacket 43 → the first hose 47 →
It is circulated through the radiator 42 → the second hose 48 → the water pump 44. At this time, the heat of combustion of the air-fuel mixture M in the cylinder 16 is radiated to the cooling water C via the water jacket 43, and then the heat of the cooling water C is radiated to the traveling wind by the radiator 42. Then, the cooling water C circulates again to the water jacket 43, and the circulation cools the cylinder 16 effectively.

The cooling device 41 is provided with a thermostat (not shown). This thermostat is for cooling the cylinder 16 to a predetermined temperature.
When the 16 outlet temperature is lower than the predetermined temperature, the cooling water C is not circulated to the radiator 42, and when the outlet temperature of the cylinder 16 of the cooling water C is higher than the predetermined temperature, the cooling water C is circulated to the radiator 42. . by this,
The temperature of the cylinder 16 is kept almost constant.
The combustion state of the air-fuel mixture M at

1 to 4, a heating device 50 for heating the vaporizer 19 is provided. This heating device 50 has a hot water passage 51 formed in the vaporizer body 20.

In particular, in the side view of the vehicle shown in FIG.
Are arranged so as to overlap a part of the sliding contact portion between the carburetor body 20 and the piston 22 and a part of the fuel supply passage 40, respectively. In the lower part of the hot water passage 51,
It is located near a main nozzle 27, which is a fuel supply port for supplying fuel to the intake passage 21, and a pilot port 37. Further, in the vertical direction, the hot water passage 51 is formed so as to extend along substantially the entire sliding portion between the carburetor body 20 and the piston 22.

The upper end of the hot water passage 51 in the longitudinal direction is an inlet 52 of the hot water.
The lower end portion is an outlet portion 53. The entrance 52
Is connected to the water jacket 43 of the cylinder 16 via an introduction pipe 54, and the outlet 53 is provided at a middle portion of the first hose 47 on the water jacket 43 side and downstream of the thermostat via a discharge pipe 55. Communication.

The hot water passage 51 is formed in the right side portion 20b of the carburetor body 20, which is the other end of the carburetor body 20 opposite to the starter lever 35 in the vehicle width direction. Also, the carburetor body 2
0, the inlet 52 and the outlet 53, the introduction pipe 54, and the discharge pipe 55 are provided on the other side.

Then, the cooling water C, which is hot water, circulates through the water jacket 43 and the hot water passage 51 of the heating device 50, so that the heat is transmitted from the hot water passage 51 to the carburetor body 20. Then, the vaporizer 19 is warmed by this heat.

In the above embodiment, since the thermostat is provided in the cooling device 41, the temperature of the cooling water C is kept substantially constant. Therefore, the temperature of the vaporizer body 20 is also reduced to the outside air temperature in summer, winter and the like. It can be kept almost constant without being affected, and as a result, the temperature of the vaporizer 19 as a whole is raised, and icing of the vaporizer 19 is prevented. Therefore, the atomization of the fuel in the carburetor 19 is favorably performed.

Further, since the hot water passage 51 of the heating device 50 is formed in the right side portion 20b of the body opposite to the throttle adjustment screw 33 and the like, the hot water passage 51 having a large heat radiation area without interfering with the throttle adjustment screw 33 and the like. Can be formed. Therefore, heat transfer from the cooling water C to the vaporizer body 20 can be increased, and the temperature of the vaporizer 19 can be effectively increased.

Further, in this embodiment, a starter lever 35 that is used more frequently than the throttle adjust screw 33 and the air adjust screw 34 is provided in the carburetor body 20, but a heating device 50 is provided in the operation space for the starter lever 35. Since the mounting space of the starter lever 35 does not interfere, the operability of the starter lever 35 is kept particularly good.

(Effects of the Invention) According to the present invention, at least a part of the sliding portion between the carburetor body and the piston, the fuel supply passage, and the hot water passage overlap with each other in a side view of the vehicle. The lower portion of the hot water passage is located near the fuel supply port.

For this reason, the sliding contact portion between the carburetor body and the piston, the fuel supply port, and the fuel supply passage, and the hot water passage are prevented from largely separating back and forth, and the sliding contact portion between the carburetor body and the piston, The fuel supply port and the fuel supply passage, which are the starting points of the occurrence of the icing phenomenon, are effectively heated by the hot water flowing through the hot water passage.

More specifically, during warm-up operation when starting the engine,
When the fuel supply passage is opened by operating the operation component, the hot water flowing through the hot water passage warms the fuel supply passage in addition to the sliding contact portion and the fuel supply port, thereby causing an icing phenomenon at the time of starting. Is prevented.

In addition, when the fuel supply passage is closed by operating the above-mentioned operation parts during normal operation after starting, etc., the sliding portion and the fuel supply port are heated by the above-mentioned hot water, thereby preventing occurrence of an icing phenomenon. .

That is, in each of the above operating states of the engine, the occurrence of the icing phenomenon is prevented.

Moreover, in the vertical direction, the hot water passage extends substantially along the entire sliding contact portion between the carburetor body and the piston. Therefore, the hot water flowing through the hot water passage causes the carburetor body and the piston to be separated from each other. The sliding contact portion is almost entirely warmed.

Therefore, the occurrence of the icing phenomenon in the sliding contact portion between the carburetor body and the piston is more reliably prevented,
Smooth sliding of the piston is ensured.

Further, as described above, since the hot water passage extends along substantially the entire sliding contact portion between the carburetor body and the piston, the hot water passage becomes vertically long, and is formed at one end of the hot water passage. The inlet and the outlet formed at the other end are largely separated vertically.

Therefore, in the work of attaching the introduction pipe and the discharge pipe to the inlet and the outlet, it is possible to prevent one of the pipes from obstructing the work of attaching the other pipe, so that these work can be easily performed. .

By the way, as described above, since the hot water passage overlaps with the fuel supply passage in a side view of the vehicle, the operation component for opening and closing the fuel supply passage and the introduction and discharge pipes communicating with the hot water passage are in a side view. And the operation to the operation component may be obstructed by the introduction and discharge pipes.

Therefore, in the present invention, the introduction pipe and the discharge pipe are disposed on the other side of the carburetor body opposite to the operation components in the vehicle width direction.

Therefore, the operation on the operation component can be performed without being disturbed by the introduction pipe and the discharge pipe.

Therefore, as described above, the hot water flowing through the hot water passage effectively warms the fuel supply passage, and the operability of the operation component that opens and closes the fuel supply passage is also maintained well.

Further, on the other side of the carburetor body opposite to the operation components in the vehicle width direction, an inlet and an outlet of the hot water passage, the introduction pipe, and the discharge pipe are disposed. It is.

For this reason, the work of attaching the introduction pipe and the discharge pipe to the inlet and the outlet of the hot water passage can be performed without being disturbed by the operation components. In addition, since the introduction pipe and the discharge pipe are arranged on the side of the carburetor body in the vehicle width direction, the mounting operation can be performed using a wide space on the side of the vehicle.

Therefore, the installation work of the introduction pipe and the discharge pipe can be extremely easily performed without being disturbed by the operation components.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a partial cross-sectional view of a carburetor, FIG.
The figure is a partially enlarged view of FIG. 2 as viewed from the back, and FIG. 4 is a partially enlarged partially sectional view of FIG. 1 ... Motorcycle, 12 ... Engine, 16 ... Cylinder,
19 ... vaporizer, 20 ... vaporizer body, 20a ... body left side (one side), 20b ... body right side (opposite side), 21 ... intake passage, 22 ... piston, 27 ... Main nozzle (fuel supply port), 35 Starter lever (operating part), 37 Pilot port (fuel supply port), 38
The other end, 39 ... One end, 40 ... Fuel supply passage, 42 ... Radiator, 43 ... Water jacket, 44 ... Water pump, 50 ... Heating device, 51 ... Hot water passage, 52 ... Inlet, 53 ... outlet part, 54 ... introduction pipe, 55 ... discharge pipe, M ... mixture, C ... cooling water (hot water).

Claims (1)

(57) [Claims] A carburetor body has an intake passage extending in the front-rear direction of the vehicle, and a piston whose axis is substantially perpendicular to the carburetor body is slidably provided in the axial direction. A lower end portion of the piston is made to be able to protrude and retract into the intake passage. A fuel supply port for supplying fuel to the intake passage is formed on an inner bottom surface of the intake passage below the piston, and an intake passage downstream of the piston is provided in the intake passage. A starting fuel supply passage is formed in the carburetor body, one end of which is open and the other end is opened in the intake passage on the upstream side of the piston, and an operating component for opening and closing the fuel supply passage is provided. Is disposed on one side of the carburetor body in the vehicle width direction. On the other hand, a hot water passage is formed in the carburetor body, and an inlet portion is provided at one longitudinal end of the hot water passage, and an outlet portion is provided at the other end. To form In the motorcycle, the inlet portion and the outlet portion are connected to a water jacket formed in an engine cylinder via an introduction pipe and a discharge pipe, and hot water can be circulated between the water jacket and the hot water passage. In a side view of the vehicle, at least a part of each of the fuel supply passage and the hot water passage overlaps with a sliding contact portion between the carburetor body and the piston, and the lower portion of the hot water passage is provided with the fuel supply passage. The hot water passage extends substantially along the entire sliding contact portion between the carburetor body and the piston in the up-down direction, and in the vehicle width direction, on the side opposite to the operation component. Heating, characterized in that an inlet and an outlet of the hot water passage, the inlet pipe, and the discharge pipe are arranged on the other side of the carburetor body.置付 vaporizer.