JPH05302534A - Throttle control device - Google Patents

Abstract

PURPOSE:To provide a throttle control device which can always smoothly follows up, irrespective of a manipulation speed of an acceleration lever, and which can obtain a stable rotational speed during idle operation of an engine. CONSTITUTION:A throttle control device is composed of a governor arm 1 coupled to a throttle lever 7 of an engine through the intermediary of a coupling member journalled rotatably about a pivot shaft 2, a throttle arm 3 coupled to an accelerating lever rotatably journalled, and a protrusion piece 10 for engaging the governor arm 1 with the throttle arm 3 upon operation of the governor arm in a valve opening direction. Further, it incorporates a governor spring 8 for urging the governor arm 1 in the valve opening direction, and a return spring having a spring force larger than that of the governor spring 9, for urging the throttle arm in the valve closing direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a throttle control device for controlling the operating speed (rotational speed) of an engine such as a general-purpose engine.

[0002]

2. Description of the Related Art Unlike engines for passenger cars and motorcycles, engines used as prime movers for transport vehicles and lawn mowers used on farms are
Even if the accelerator lever (which includes the concept of the accelerator pedal) is quickly operated, it is preferable that the engine speed is accelerated relatively slowly and smoothly. It is preferable to control so as not to exceed a predetermined engine rotation speed (a specific rotation speed suitable for operation) even if the valve is operated in the valve opening direction.

Therefore, conventionally, in the case of this type of engine, a throttle control device is provided between the throttle lever and the accelerator lever of the carburetor of the engine.
This throttle control device is mounted on a pivot shaft 2 ', as shown in FIG.
Governor arm 1'rotatable around a control panel, throttle arm 3'rotatably supported by a control panel 5 ', the governor arm 1'and carburetor (engine)
A connecting rod 12 for connecting the C throttle lever 7 and
A governor spring 8'which elastically connects the governor arm 1'and the throttle arm 3 ', and a centrifugal force which is arranged on a rotary shaft (an output shaft of an engine or an input shaft or an output shaft of a transmission) to be controlled. Thus, the governor assembly 1 for suppressing the operation of the governor arm 1'to the valve opening side more than a predetermined value is provided.

By connecting the throttle arm 3'to the accelerator lever side (not shown) with an accelerator wire 11 (or rod), as described above, the accelerator lever is quickly operated in the valve opening direction (acceleration operation). In spite of this, relatively slow and smooth acceleration is performed, and the engine is designed so that the engine rotation speed does not exceed the predetermined speed even in the normal operation region of the accelerator lever or higher. As a prior art of such a throttle control device, there is JP-A-60-56154.

[0005]

However, in the case of the throttle control device having the above structure, when the accelerator lever is quickly operated in the valve opening direction, the throttle arm 3'and the governor arm 1'can be extended and contracted as described above. Due to the direct connection by the governor spring 8 ',
It is difficult for the followability at the time of acceleration, particularly the followability at the beginning of operation, to be linearly and smoothly performed.

If the governor spring 8'is made to have a small spring force in order to smoothly and smoothly operate the governor arm 1'with respect to the operation of the throttle arm 3 ', the governor assembly G and the operation of the governor assembly G are affected. This makes it difficult to stabilize the rotation of the engine when idling.

The present invention has been made in view of such a situation as described above, and always follows slowly and smoothly regardless of the operation speed of the accelerator lever, and the throttle control device can obtain stable rotation even when the engine is idling. The purpose is to provide.

[0008]

A throttle control device according to the present invention is interposed between a throttle lever and an accelerator lever of an engine, and always operates at a slow speed regardless of the operating speed of the accelerator lever in the valve opening direction. (EN) A throttle control device that operates a throttle lever and suppresses an engine rotation speed to a predetermined rotation speed or less by a governor assembly attached to a rotating shaft, which rotates around a pivot shaft equipped with a governor assembly. A governor arm that is rotatably supported and is connected to the throttle lever of the engine through a connecting member at a portion separated from the pivot portion, and a governor arm that is pivotally supported and is separated from the pivot portion is connected to an accelerator lever. Away from the throttle arm and the pivotal support of the governor arm. A portion and spaced portions of pivot journal section of the throttle arm, engaging means for engaging in the valve closing operation direction of the operation of the governor arm, and governor spring biasing the governor arm in the valve opening operation direction,
A return spring, which has a stronger spring force than the governor spring and biases the throttle arm in the valve closing direction, is provided.

[0009]

However, according to the throttle control device of the present invention, since the throttle arm and the governor arm are not directly connected to each other, even if the accelerator lever is quickly operated in the valve opening operation direction, it is related to the operation speed. The governor arm always operates at a slow speed according to the spring force of the governor spring.Therefore, the throttle lever of the engine connected to this governor arm always operates at a constant slow speed regardless of the operation speed of the accelerator lever. Take action. Then, when the accelerator lever is operated in the valve closing direction, the engaging means for engaging the throttle arm and the governor arm engages the throttle arm with the governor arm and moves the governor arm at a speed corresponding to the operation speed of the accelerator lever. As a result, the throttle lever of the engine connected to the governor arm by the connecting member can be operated according to the operation speed of the accelerator lever.

The governor spring urges the governor arm in the valve opening operation direction, while the return spring urges the throttle arm in the valve closing operation direction by a stronger spring force. It is in a state of being pressed in the valve closing direction via the coupling means. Therefore, if the limit in the valve closing direction of the throttle arm (throttle lever idling state) is provided at the rotational speed at which the engine rotates stably, the engine will rotate stably.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view showing a general construction of a throttle control device according to an embodiment of the present invention having a partial cross section and a notch.

In FIG. 1, 1 is a governor arm, 2 is a pivot shaft for pivotally supporting the governor arm 1, 3 is a throttle arm, 4 is a pivot member for pivotally supporting the throttle arm 3 on a control panel 5, and 6 is a control panel. A spring locking lever fixed to 5 and a carburetor throttle lever 7 are provided.

As shown in FIG. 1, the governor arm 1 is located on a virtual plane parallel to the control panel 5 by the pivot shaft 2 from a position shown by a solid line to a position shown by a two-dot chain line about the pivot shaft 2 as a center. The pivot shaft 2 is pivotally supported about the pivot shaft 2.
The pivot shaft 2 is mounted on the output shaft (or the output shaft or the input shaft of the transmission) of the engine (not shown).
When the shaft to which the governor assembly G is attached is about to exceed a predetermined rotation speed, the governor assembly G is actuated to open the governor arm 1 in the valve opening direction (Fig. 1 is configured to act to suppress the movement in the counterclockwise direction.

Further, the governor arm 1 is elastically locked to the spring locking lever 6 via the governor spring 8 at a position in the middle in the longitudinal direction, so that the governor arm 1 is attached in the valve opening direction. It is energized. The spring force of the governor spring 8 is set to be smaller than the restraining force (centrifugal force) of the governor assembly G described above and to allow the governor arm 1 to rotate slowly.

The tip of the governor arm 1 is
It is connected to the throttle lever 7 of the carburetor C on the engine side via a connecting rod 12 which is a connecting member.

Further, the throttle arm 3 is indicated by a two-dot chain line from a position indicated by a solid line by a pivot member 4 in a plane different from the plane in which the governor arm 1 rotates in the depth direction of the drawing in FIG. The pivot member 4 is pivotally supported so as to be rotatable about the pivot member 4 up to the position shown (correctly, the position where it abuts on the abutment piece 5a of the control panel 5 which is rotated slightly counterclockwise from the position indicated by the two-dot chain line). ing. This rotation range is restricted by the throttle arm 3 coming into contact with the projecting piece 5a of the control panel 5 in the valve opening operation direction (counterclockwise direction in FIG. 1), and is controlled in the valve closing operation direction. It is regulated by coming into contact with an idle screw 14 arranged on the panel 5 side. The protrusion 5a is configured such that the control panel 5 itself is moved (rotated) with respect to a fixing member (not shown), and the idle screw 14 is adjustable by the screwing degree of the screw. There is.

The governor arm 1 and the valve closing direction (in FIG. 1) are separated from the pivot member 4 of the throttle arm 3 (in this embodiment, above the pivot member 4). A cylindrical projecting piece 10 (engaging means) that engages in the (clockwise) operation is fixed to the upper surface of the throttle arm 3. Further, one end of an accelerator wire 11 whose other end is connected to an accelerator lever (not shown) is connected to a portion of the projecting piece 10 on the further tip side. A spring locking hole 3a is formed in a portion of the throttle arm 3 on the opposite side of the pivotal supporting member 4, and the spring locking hole 3a is formed in the spring locking hole 3a and the spring locking lever 6 is formed in the other end. One end of the engaged return spring 9 is locked and biases the throttle arm 3 in the valve closing direction. Further, below the spring locking hole 3a, a contact member 3A that contacts the tip of the idle screw 14 is attached. By the way, the return spring 9 has a spring force larger than the spring force of the governor spring 8 in order to hold the engine in an idle state when the accelerator lever is not operated.

Further, in FIG. 1, reference numeral 15 denotes a weight of the governor assembly G which moves in the outer peripheral direction by centrifugal force,
Reference numeral 16 is a weight for returning the weight 15 to the inner circumferential direction by gravity when the rotation speed is low. Further, 17 is a choke lever of the carburetor C.

However, the throttle control device thus constructed operates as follows.

That is, when the engine is operating in the idling state, as shown in FIG. 1, in the governor assembly G, the weight acting on the weight 16 is weighted.
The centrifugal force acting on 15 is exceeded, and the state shown by the solid line in FIG. 1 is reached. As a result, the force for rotating the pivot shaft 2 pivotally supporting the governor arm 1 in the clockwise direction in FIG. 1 does not work.

The governor spring 8 urges the governor arm 1 in the valve opening operation direction, but the return spring 9 urges the throttle arm 3 in the valve closing operation direction with a stronger spring force. As shown in FIG. 1, 1 is in a state of being pressed in the valve closing direction via the projecting piece 10. That is, the contact member 3A of the throttle arm 3 is in a pressed state until it contacts the idle screw 14.

Therefore, by adjusting the idle screw 14, the engine can be adjusted to a stable idle state.

When the accelerator lever (not shown) is rapidly operated in the valve opening direction from this idle state,
When the operation speed is high, that is, when the accelerator lever is operated at a speed faster than the speed at which the governor spring 8 opens the governor arm 1.
Although the accelerator wire 11 is pulled in the direction of the arrow X and the protrusion 10 of the throttle arm 3 separates from the governor arm 1, the governor arm 1 itself opens at a constant slow speed according to the spring force of the governor spring 8. Rotate in the valve operating direction. Therefore, the throttle lever 7 of the carburetor C connected to the governor arm 1 by the connecting rod 12 always operates slowly and smoothly in the valve opening operation direction regardless of the operation speed of the accelerator lever. Become.

On the other hand, when the accelerator lever is operated in the valve closing direction from the state where the throttle arm 3 is operating at a predetermined rotational speed, the throttle arm 3 is rotated clockwise by the spring force of the return spring 9 in accordance with the operating speed. The protrusion 10 of the throttle arm 3 comes into contact with the governor arm 1 in response to the rotation, and presses the governor arm 1 in the valve closing direction. Therefore, the throttle lever 7 of the carburetor C that is connected to the governor arm 1 by the connecting rod 12.
Also, with the operation of the governor arm 1 in the valve closing direction, the governor arm 1 is operated according to the operation speed of the accelerator lever.

Therefore, according to this throttle control device,
When the valve is opened, the throttle lever of the engine operates slowly and smoothly regardless of the operating speed even if the accelerator lever operates quickly.When the valve is closed, the engine throttle speed is proportional to the operating speed of the accelerator lever. The throttle lever can be operated quickly, and moreover,
Stable rotation will be obtained even when the engine is idling.

Next, another embodiment in which the throttle control device having the above configuration is mounted on an actual vehicle will be described with reference to FIG.

In the embodiment shown in FIG. 1, the governor arm and the throttle arm are arranged at one place, but when actually used, for example, as shown in FIGS. 2 (a) and 2 (b). In the case where the engine and the transmission are separated from each other by distance, when a governor assembly (not shown) is provided on the output shaft (or the input shaft) of the transmission M,
In this transmission M, all the configurations except the governor spring 8 having the configuration shown in FIG. 1 described above, that is, the governor arm 1, the throttle arm 3 having the projecting piece 10, the return spring 9 and the like are arranged, and further, A governor arm auxiliary link 1A that is interlocked with the governor arm 1 via a rigid link 19 is arranged on the engine E side. A governor spring 8 is arranged between the governor arm auxiliary link 1A and a spring locking lever 6 provided on the engine side control panel 5A, and the tip of the governor arm auxiliary link 1A and a carburetor not shown. Even if the throttle lever is connected by the connecting rod 12, the same effect as the embodiment of FIG. 1 can be obtained.

With the construction of the embodiment shown in FIG. 2, the output shaft of the transmission proportional to the actual vehicle speed even when the engine and the transmission in the transport vehicle transmit the driving force through the torque converter. Since the governor assembly described above operates due to the rotation of (or the input shaft),
Optimal speed control can be obtained even when climbing a slope.

[0030]

As described above, according to the throttle control device of the present invention, even if the accelerator lever is quickly operated, the throttle lever of the engine operates slowly and smoothly regardless of the operating speed of the engine, and Stable rotation can be obtained even when idling.

Therefore, the transport vehicle, the lawnmower, and the like equipped with the throttle control device can obtain a more appropriate operation state, and as a result, the workability thereof can be improved.

[Brief description of drawings]

FIG. 1 is a front view showing a general configuration of a throttle control device according to an embodiment of the present invention with a partial cross section and a notch.

2 (a) is a plan view showing the overall construction of a throttle device showing another embodiment different from FIG. 1, and FIG. 2 (b) is a side view of FIG. 2 (a).

FIG. 3 is a front view showing a configuration of a conventional throttle control device with a partial cross section and a notch.

[Explanation of symbols]

 1 ... Governor arm 2 ... Pivot shaft 3 ... Throttle arm 7 ... Throttle lever 8 ... Governor spring 9 ... Return spring 10 ... Projection piece (engaging means) 12 ... Connecting rod (connecting member) G ... Governor assembly

Claims (1)

[Claims] 1. A throttle lever, which is interposed between an engine throttle lever and an accelerator lever, always operates the throttle lever at a slow speed regardless of the operating speed in the valve opening direction of the accelerator lever, and is attached to a rotary shaft. A throttle control device that functions to suppress the engine rotation speed to below a predetermined rotation speed by a governor assembly, which is rotatably pivoted about a pivot shaft equipped with the governor assembly and is a portion separated from this pivot portion. The governor arm connected to the throttle lever of the engine through the connecting member, the throttle arm pivotally supported and connected to the accelerator lever at a part separated from this pivot part, and the pivot part of the governor arm. The part separated from the pivotal part of the throttle arm An engaging means for engaging in the operation of the governor arm in the valve closing operation direction, a governor spring for urging the governor arm in the valve opening operation direction, and a spring force stronger than the governor spring to close the throttle arm. A throttle control device, comprising: a return spring for urging in a valve operation direction.