JP3972566B2 - Outboard motor throttle structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a throttle structure for an outboard motor.
[0002]
[Prior art]
Some engines perform output adjustment by opening / closing a throttle body or a throttle valve in a carburetor to increase or decrease the inflow air amount. The opening / closing operation of the throttle valve is usually performed by remote control through a cable or a rod.
[0003]
FIG. 8 shows an example of a carburetor used in an outboard motor, for example. As shown in FIG. 8, a throttle valve 3 is pivotally supported by a throttle shaft 4 in an intake passage 2 in the carburetor 1, and a throttle shaft plate 5 rotates at the end of the throttle shaft 4 protruding outside the carburetor 1. It can be mounted in one piece. One end of a throttle cable 6 is connected to the throttle shaft plate 5 and the throttle valve 3 is opened by pulling the throttle cable.
[0004]
The throttle shaft 4 is provided with a return spring 7. When the pulling operation of the throttle cable 6 is loosened, the return spring 7 closes the throttle valve 3.
[0005]
FIG. 9 shows another example of a carburetor used in, for example, an outboard motor. As shown in FIG. 9, a throttle valve 13 is rotatably supported by a throttle shaft 14 in an intake passage 12 in the carburetor 11, and a throttle shaft plate 15 is attached to the end of the throttle shaft 14 protruding outside the carburetor 11. It is done. On the other hand, a throttle drum 16 is provided separately from the carburetor 11, and the throttle drum 16 and the throttle shaft plate 15 are operatively connected by a rod 17. One end of each of the main throttle cable 18 and the sub throttle cable 19 is connected to the throttle drum 16, and the throttle valve 13 is opened by pulling the main throttle cable 18, and the sub throttle cable 19 is The throttle valve 13 is closed by the pulling operation. This opening / closing method is generally called a forced opening / closing method.
[0006]
[Problems to be solved by the invention]
However, when the throttle valve is closed using a return spring, if the throttle shaft is fixed due to salt damage or the like, the opening / closing operation of the throttle valve becomes heavy and the operability is poor.
[0007]
Further, in the case of the forced opening / closing method, the structure is complicated, the number of parts is large, and there are many adjustment points, which is not preferable.
[0008]
The present invention has been made in consideration of the above-described circumstances, and an object of the present invention is to provide a throttle structure for an outboard motor that can be easily opened and closed with a simple structure.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the throttle structure for an outboard motor according to the present invention has a tiller handle extending forward in front of the engine and an engine output at the tip thereof. An outboard motor that is provided with an adjusting throttle grip so as to be rotatable in the circumferential direction, and that has a carburetor in the engine, and that opens and closes a throttle valve provided on the carburetor using a throttle cable extending from the throttle grip. The throttle drum is pivotally integrated with the end of the throttle grip, and one end of each of the main throttle cable and the sub-throttle cable is connected to the throttle drum with its center in between, while the throttle valve has a return spring. The above-mentioned key is provided by the equipped throttle shaft. A throttle shaft plate is pivotally supported by the bleeder and is attached to the end of the throttle shaft projecting out of the carburetor. The throttle shaft plate extends to both sides around the throttle shaft, and both end portions thereof. Are connected to the respective ends of the main throttle cable and the sub throttle cable, and an engagement hole is formed at the end of the throttle shaft plate on the side to which the end of the sub throttle cable is connected. An end pin provided at the end of the sub-throttle cable is disposed so as to be engageable, and the engagement hole opens and closes the throttle valve smoothly by operating the main throttle cable and the return spring without trouble. In the state, the throttle Set the position and shape so that the end pin of the sub throttle cable does not lock regardless of the position of the shaft plate.If the throttle valve does not open and close smoothly, close the throttle grip. The sub-throttle cable is pulled and the end pin at the end is locked in the engagement hole of the throttle shaft plate, so that the throttle valve is forcibly closed .
[0010]
In order to solve the above-mentioned problem, as described in claim 2, a choke valve is rotatably supported by a choke shaft upstream of the throttle valve of the carburetor and protrudes out of the carburetor. A choke shaft plate is pivotally attached to the end of the choke shaft, and the carburetor is provided with restricting means for restricting the position of the throttle valve when the choke is used. The restricting means protrudes integrally with the throttle shaft plate. And a stopper portion extending from the choke shaft plate. The choke shaft plate is in a state where the choke shaft plate is in contact with the stopper portion of the choke shaft plate. The throttle valve is positioned at the opening when the engine is started. One in which was set to.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0013]
FIG. 1 is a right side view showing an example of an outboard motor according to the present invention. As shown in FIG. 1, the outboard motor 21 has a box-shaped engine cover 22 at the top, and a vertical (vertical) engine 23 is accommodated therein. A tiller handle 24 extends forward from the front lower part (right side in the figure) of the engine 23, and a throttle grip 25 for adjusting engine output is provided at the tip thereof.
[0014]
A drive shaft housing 26 is provided below the engine cover 22, and a gear case 27 is provided below the drive shaft housing 26. A propeller shaft 28 is pivotally supported inside the gear case 27, and a propeller 29 is provided at the rear end thereof.
[0015]
In the engine 23, the crankshaft 30 is provided vertically (vertical) so as to face substantially the vertical direction. A drive shaft 31 connected to the lower end of the crankshaft 30 extends downward in the drive shaft housing 26, and the lower end of the drive shaft 31 is connected to the propeller shaft 28 via a bevel gear 32. The output of the engine 23, that is, the rotation of the crankshaft 30 is transmitted to the propeller shaft 28 via the drive shaft 31 and the bevel gear 32 to rotate the propeller 29.
[0016]
The upper portion of the drive shaft housing 26 is rotatably supported by a rotation support portion 33a of the clamp bracket 33, and the clamp bracket 33 is fixed to a transom 34a of the marine vessel 34. That is, the outboard motor 21 is provided so as to be able to rotate about 360 ° with respect to the ship 34, and the ship 34 is steered by changing the direction of the entire outboard motor 21 by swinging the tiller handle 24 in the horizontal direction. It is configured to be able to.
[0017]
On the other hand, the engine 23 used in the present embodiment is, for example, a four-cycle single-cylinder engine. The engine 23 includes a vertically-divided crankcase 35 disposed on the front side (right side in FIG. 1) of the outboard motor 21, and A cylinder block 36 disposed on the rear side (left side in FIG. 1) of the crankcase 35 and formed integrally with an upper portion of the crankcase 35, and disposed on the rear side (left side in FIG. 1) of the cylinder block 36. And a cylinder head 37. The engine 23 is fixed on an extension case 38 provided at the upper end portion of the drive shaft housing 26. In addition, a flywheel / magnet device 39 for power generation and a rope / recoil type engine starting device 40 are provided at the upper end of the crankshaft 30.
[0018]
FIG. 2 is a plan view of the engine 23. As shown in FIG. 2, a carburetor 41 constituting an intake device is disposed on the upper portion of the cylinder block 36, and a downstream side thereof is connected to an intake port (not shown) that opens to the upper surface of the cylinder head 37 via an inlet pipe 42. In addition to being connected, a silencer 43 is connected to the upstream side of the carburetor 41.
[0019]
FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 1 and shows the structure of the tiller handle 24. As shown in FIG. 3, a throttle grip 25 is attached to the free end of the tiller handle 24 so as to be rotatable in the circumferential direction. From the throttle grip 25, a throttle rod 44 provided integrally with the throttle grip 25 extends into the tiller handle 24, and a throttle drum 45 is provided integrally with the end thereof.
[0020]
Although not shown in detail, one end of each of the main throttle cable 46 and the sub throttle cable 47 is connected to the throttle drum 45, and either one of them is operated by rotating the throttle grip 25. The cable is pulled. As shown in FIG. 2, the main throttle cable 46 and the sub throttle cable 47 are guided into the engine cover 21 and extend toward the carburetor 41. The main throttle cable 46 and the sub throttle cable 47 are held by a cable holder 48 in the vicinity of the carburetor 41.
[0021]
4 is an enlarged plan view of the carburetor 41, and FIG. 5 is a view taken in the direction of arrow V in FIG. As shown in FIGS. 4 and 5, in the intake passage 49 in the carburetor 41, a throttle valve 50 that adjusts the output of the engine 23 by increasing or decreasing the amount of inflow air in the intake passage 49 is rotatable by a throttle shaft 51. The throttle shaft plate 52 is pivotally attached to the end of the throttle shaft 51 that is pivotally supported by the carburetor 41 and protrudes outside the carburetor 41. The throttle shaft 51 is provided with a return spring 53. FIG. 4 shows a state where the throttle valve 50 is closed (fully closed). FIG. 6 shows a state in which the throttle valve 50 is opened (fully opened).
[0022]
Further, a choke valve 54 that adjusts the amount of air flowing into the intake passage 49 at the start of the engine 23 to temporarily increase the air-fuel ratio upstream of the throttle valve 50 is pivotally supported by a choke shaft 55. A choke shaft plate 56 is pivotally attached to the end of the choke shaft 55 protruding outside the carburetor 41. As shown in FIG. 2, the choke knob 57 provided outside the outboard motor 21 is operatively connected to the choke shaft plate 56 via the choke rod 58.
[0023]
The throttle shaft plate 52 extends, for example, on both sides in the width direction of the carburetor 41 around the throttle shaft 51, and the end of the main throttle cable 46 is connected to one end thereof. When the throttle grip 25 is opened and the main throttle cable 46 is pulled, the throttle valve 50 is opened. Since the throttle shaft 51 is provided with a return spring 53, the throttle valve 50 is automatically closed by the return spring 53 when the opening operation of the throttle grip 25 is loosened.
[0024]
By the way, the carburetor 41 is provided with restricting means for restricting the position of the throttle valve 50 when the choke is used. Specifically, as shown in FIG. 7, a position setting projection 59 is integrally formed on the throttle shaft plate 52, and a position regulating stopper 60 is extended on the choke shaft plate 56. The The throttle valve 50 is set to the opening when the engine 23 is started in a state where the projection 59 of the throttle shaft plate 52 is in contact with the stopper 60 of the choke shaft plate 56 in a state where the choke is used. .
[0025]
On the other hand, an engagement hole 61 is formed at the end of the throttle shaft plate 52 opposite to the main throttle cable 46 attachment portion across the throttle shaft 51, and the engagement hole 61 is provided at the end of the sub-throttle cable 47. The end pin 62 is arranged to be engageable. This engagement hole 61 is provided at the end of the sub-throttle cable 47 regardless of the position of the throttle shaft plate 52 in a state in which the main throttle cable 46 and the return spring 53 operate without trouble and the throttle valve 50 opens and closes smoothly. The position and shape of the end pin 62 are set to, for example, an arc-shaped long hole so that the end pin 62 is not locked. That is, as long as the throttle valve 50 is opened and closed smoothly, the sub-throttle cable 47 that moves forward and backward by the operation of the throttle grip 25 does not interfere with the opening and closing operation of the throttle valve 50.
[0026]
However, if the operation of the main throttle cable 46 and the return spring 53 becomes heavy and the throttle valve 50 cannot be opened and closed smoothly due to some reason such as salt content in seawater, the throttle grip 25 is forcibly set. By performing the closing operation, the sub-throttle cable 47 is pulled, and the end pin 62 at the end thereof is locked in the engagement hole 61 of the throttle shaft 51, so that the throttle valve 50 is forcibly closed (see FIG. 7). . At this time, the throttle valve 50 is set to be able to be closed with the opening degree when the engine 23 is started (when the choke is used) limited, and the engine 23 will not stop even if the throttle grip 25 is forcibly closed. .
[0027]
As this setting method, for example, as shown in FIG. 7, the length of the sub-throttle cable 47 is set while the projection 59 of the throttle shaft plate 52 is in contact with the stopper 60 of the choke shaft plate 56 when the choke is used. It becomes possible by adjusting.
[0028]
Next, the operation of this embodiment will be described.
[0029]
By opening and closing the throttle valve 50 using two throttle cables and using only one of them for forced closing operation, the structure is simpler than the conventional throttle valve 50 opening and closing method. Thus, the number of parts and the number of assembly steps can be reduced, and the throttle valve 50 can be reliably closed even if the operation of the main throttle cable 46 and the return spring 53 becomes heavy for some reason.
[0030]
In addition, since the sub-throttle cable 47 that normally advances and retreats by operating the throttle grip 25 does not interfere with the opening / closing operation of the throttle valve 50, the opening / closing of the throttle valve 50 can be smoothly performed with a light feeling.
[0031]
Further, there is provided a means for restricting the position of the throttle valve 50 when the choke is used, and when the throttle valve 50 is forcibly closed, the throttle valve 50 is set to be closed at the opening when the engine 23 is started (when the choke is used). As a result, the length of the sub-throttle cable 47 can be easily adjusted.
[0032]
【The invention's effect】
As described above, according to the throttle structure of the outboard motor according to the present invention, the tiller handle is extended forward in front of the engine, and the throttle grip for adjusting the engine output is provided at the tip thereof in the circumferential direction. In an outboard motor that is provided rotatably and has a carburetor in the engine and opens and closes a throttle valve provided in the carburetor using a throttle cable extending from the throttle grip, a throttle is provided at an end of the throttle grip. A drum is pivotally integrated, and one end of each of the main throttle cable and sub-throttle cable is connected to the throttle drum with its center in between, while the throttle valve is pivoted to the carburetor by a throttle shaft having a return spring. Is freely supported, A throttle shaft plate is pivotally attached to the end of the throttle shaft that protrudes outside the carburetor. The throttle shaft plate extends to both sides around the throttle shaft, and the main throttle cable and the sub-throttle cable are connected to both ends of the throttle shaft plate. Since the respective ends are connected, the structure is simplified, the number of parts and the number of assembly steps can be reduced, and the throttle valve can be reliably closed.
[0033]
In addition, an engagement hole is formed at the end of the throttle shaft plate on the side to which the end of the sub-throttle cable is connected, and an end pin provided at the end of the sub-throttle cable can be engaged with the engagement hole. In addition, the engagement hole is arranged so that the sub throttle shaft plate is located at any position in the state where the main throttle cable and the return spring operate without trouble and the throttle valve opens and closes smoothly. The position and shape of the throttle cable are set so that the end pin at the end of the throttle cable is not locked.If the throttle valve does not open and close smoothly, the sub throttle cable is pulled by closing the throttle grip and the end of the throttle valve is pulled. End pin of throttle shaft plate Engaged in Goana, since the set to close the throttle valve to force, together with the operation of the throttle valve is increased, also ensures the opening and closing of the throttle valve.
[0034]
Further, a choke valve is pivotally supported by a choke shaft upstream of the throttle valve of the carburetor, and a choke shaft plate is integrally attached to the end of the choke shaft projecting out of the carburetor. The carburetor is provided with a restricting means for restricting the position of the throttle valve when the choke is used, and the restricting means includes a protrusion part integrally projecting on the throttle shaft plate and a stopper part extending on the choke shaft plate. The throttle valve is set so that the throttle valve is positioned at the opening when the engine is started with the projection of the throttle shaft plate in contact with the stopper of the choke shaft plate in a state where the choke is used. Forcibly closing the valve If it, the length adjustment of the sub-throttle cable is facilitated by setting the throttle valve to close the opening at the start of the engine to the limit.
[Brief description of the drawings]
FIG. 1 is a right side view of an outboard motor showing an embodiment of a throttle structure of the outboard motor according to the present invention.
FIG. 2 is a plan view of the engine.
3 is a cross-sectional view taken along line III-III in FIG.
FIG. 4 is an enlarged plan view of the carburetor (with the throttle valve closed).
FIG. 5 is a view taken along the arrow V in FIG. 4;
FIG. 6 is an enlarged plan view of the carburetor (with the throttle valve opened).
FIG. 7 is an enlarged plan view of the carburetor (with the choke used).
FIG. 8 is a view showing an example of a carburetor used in a conventional outboard motor.
FIG. 9 is a view showing another example of a carburetor used in a conventional outboard motor.
[Explanation of symbols]
21 Outboard motor 23 Engine 24 Tiller handle 25 Throttle grip 41 Carburetor 45 Throttle drum 46 Main throttle cable 47 Sub throttle cable 50 Throttle valve 51 Throttle shaft 52 Throttle shaft plate 53 Return spring 54 Choke valve 55 Choke shaft 56 Choke shaft plate 59 Projection Part 60 stopper part 61 engagement hole 62 end pin

Claims (2)

A tiller handle is extended forward in front of the engine, and a throttle grip for adjusting engine output is provided at the tip of the engine so as to be rotatable in the circumferential direction, and a carburetor is provided in the engine. In an outboard motor that opens and closes the throttle valve using a throttle cable extending from the throttle grip, a throttle drum is provided integrally with the end of the throttle grip, and the center of the throttle drum is sandwiched between the main throttle cables. The throttle valve is pivotally supported on the carburetor by a throttle shaft having a return spring, and is connected to the throttle shaft end protruding outside the carburetor. While with attaching the door plate to rotate integrally, the throttle shaft plate extends on both sides about said throttle shaft, connecting the respective ends of the main throttle cable and the sub throttle cable at both ends, the sub-throttle cable An engagement hole is formed in the end of the throttle shaft plate on the side to which the end of the sub-throttle is connected, and an end pin provided at the end of the sub-throttle cable is disposed in the engagement hole so as to be engageable. In the state where the main throttle cable and the return spring operate without trouble and the throttle valve opens and closes smoothly, the engagement hole is provided with an end pin at the end of the sub-throttle cable regardless of the position of the throttle shaft plate. Do not lock If the throttle valve does not open and close smoothly while setting its position and shape, the sub-throttle cable is pulled by closing the throttle grip and the end pin at the end engages with the engagement hole of the throttle shaft plate. A throttle structure for an outboard motor that is set to stop and forcibly close the throttle valve . A choke valve is rotatably supported by a choke shaft upstream of the throttle valve of the carburetor, and a choke shaft plate is integrally attached to the end of the choke shaft projecting out of the carburetor. Is provided with a restricting means for restricting the position of the throttle valve when the choke is used, and the restricting means is constituted by a protrusion part integrally protruding on the throttle shaft plate and a stopper part extending on the choke shaft plate. 2. The throttle valve is set so that the throttle valve is positioned at the opening when the engine is started with the projection of the throttle shaft plate in contact with the stopper of the choke shaft plate in a state where the choke is used. Outboard motor throttle structure.

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