JPH0133797Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention is an improvement to the arrangement of the governor device in a crankshaft cantilever type engine.

The governor device, which controls the throttle of the carburetor that supplies fuel to the combustion chamber of the engine according to the rotational speed of the crankshaft, has generally been constructed in the camshaft section that operates the engine's valve mechanism. Recently, a shaft is provided separately from the crankshaft and camshaft, a governor device is configured on the shaft, and the shaft is driven by a transmission mechanism such as a gear to increase the rotation speed, thereby improving the performance of the governor device. More and more people are starting to do this.

However, the conventional governor device described above first requires a power transmission mechanism such as a gear, and further requires a separate shaft from the crankshaft for rotating the governor device, which complicates the structure and increases the number of parts. There are also many.

The above problem is the same in engines with a cantilevered crankshaft.Since the crankshaft is cantilevered and the gear mechanism is concentrated on the cantilevered shaft, the transmission mechanism such as gears cannot be connected to other gears. It is difficult to coexist with a mechanism, and if a camshaft is used, the rotation speed is 1/2 that of a crankshaft, so it is difficult to obtain a high rotation speed for the governor device, and if you try to increase the speed, It requires a separate transmission mechanism and governor support shaft, which is disadvantageous in that it complicates the structure and increases the number of parts.

By the way, in a crankshaft cantilever type engine, there is a space on one side of the crankpin, that is, in the direction of the end face of the crank web. The present invention was created by focusing on the fact that it can be easily extracted and is advantageous in terms of function guarantee.

The present invention allows the governor device to be arranged without requiring a power transmission mechanism such as a gear or a separate shaft, especially in a crankshaft cantilever type engine, and therefore the structure for arranging and configuring the governor device is simple. In addition, the object of this invention is to provide a governor device for a crankshaft cantilever type engine that requires a minimum number of parts and that also allows the governor device to rotate at the same high speed as the crankshaft to achieve higher performance. It is what was done.

In order to achieve such an object, the present invention fixes a holder of a governor device to the end face of a crank pin of a crankshaft supported on a cantilever, extends the holder to the axis of the crankshaft, and slides a governor slider. The gist is that the axis of the freely supported center pin is aligned with the axis of the crankshaft, and the governor device is mounted on the extending portion of the holder.

A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a longitudinal side view of the engine, and FIG. 2 is a longitudinal front view of the engine, showing the cut portions of the left and right halves with different phases in the front and rear.

As shown in the drawings, the engine 10 is a vertical crankshaft type engine (vertical engine) in which a crankshaft 30 is supported vertically and cantilevered at the bottom, and the cylinder 16 is oriented horizontally and the crankcase 11 is oriented vertically. The crank case 11, the cylinder block 17 and the cylinder head 18 constituting the cylinder 16 are integrally cast to form the case.

An opening 12 is formed in the upper part of the crankcase 11 and is cut diagonally from the base of the cylinder 16, and this opening 12 is removably covered with a cover 21 made of a press-formed steel plate. The upper plate 21a of the cover 21 is formed to bulge upward, and a breather 41 is attached to the cover upper plate 21a. Further, on the lower surface side of the cover upper plate 21a, a plate 42 protruding downward is installed horizontally, and the plate 42 functions as a baffle plate for the breather 41, and its lower surface also functions as an oil guide. The most downwardly bulging portion 43 of the plate 42 is made to substantially coincide with the axis C portion of the crankshaft 30.

A piston 23 is slidably fitted into the cylinder 16, a spark plug 25 is installed diagonally from the front upper part of the cylinder head 18, and two left and right intake/exhaust valves 26, 26 ( In Fig. 1, one (1) is installed because it is a longitudinal side. The valve stem 27 of the valve 26 is engaged with one end of each rocker arm 28, and the tip of a push rod 29 is engaged with the other end of each rocker arm 28, respectively.
This push rod 29 is located below the cylinder 16 and is connected to a push rod passage 19 formed at the bottom of the cylinder block 17 and the cylinder head 18.
A cover 22 made of a steel plate is attached from the front of the cylinder head 18.

On the other hand, a crankshaft 30 is vertically supported from above on the crankcase 11 by a shaft part 31 constituting the lower part of the crankcase 11, and is rotatably supported by upper and lower bearing parts 13, 14 at the lower part of the crankshaft 30. It has a cantilevered structure consisting of a shaft portion 31, a crank web 35, and a crank pin 36, and the crank pin 36 and the piston pin 24 of the piston 23 are connected by a connecting rod 44.

The upper and lower journals 3 of the shaft portion 31 of such a crankshaft 30 are supported cantilevered at the lower part.
A gear 34 is formed on the shaft periphery between the upper and lower bearing parts 13 and 14 of the crankcase 11, and a recess 1 facing the gear 34 is formed on the cylinder 16 side between the upper and lower bearing parts 13 and 14 of the crankcase 11.
5 is horizontally formed, and a camshaft 50 is installed horizontally in this recess 15, and this camshaft 50
A gear 51 formed as shown in FIG. Cams 52, 52 are formed on both sides of the gear 51 of this camshaft 50.
The base end of a lifter 53 connected to the base end of the push rod 29 and inserted into a guide hole 19b formed in the base end wall 19a of the passage 19 abuts and engages with the lifter 53.

An oil slinger 54 is attached to one end of the camshaft 50, and an oil slinger 54 is attached to one end of the camshaft 50.
A gear 56 formed on an output shaft 55 disposed horizontally on substantially the same plane as the camshaft 50 and orthogonal to the camshaft 50 is orthogonally meshed with the gear 34 of the crankshaft 3 .
The driving force taken out directly from the engine 10 to the output shaft 55 is output via a clutch mechanism to the axle of a working machine such as a lawn mower on which the engine 10 is mounted. Furthermore, a blade 46 is attached to the lower shaft end 31a of the crankshaft 30, which projects downward from the crankcase 11, via a holder 45, since it is an engine used in a lawn mower in this embodiment.

In this invention, the above crankshaft 3
The governor device 60 is disposed using a space above the crank web 35 of the engine 10, in which the engine 10 is supported on a cantilever.

That is, the base 62 of the holder plate 61 of the governor device 60 is bolted 38 to the upper end surface of the crank pin 36, and the two notch holes 37, 37 formed in the upper end surface of the crank pin 36 are integrally connected to the holder plate base 62. The holder plate 61 is fixed to the upper end surface of the crank pin 36 by engaging the downwardly formed half-opened notches 63, 63 (both of which are shown only one in FIG. The base 62 of the plate 61 is connected to the connecting rod 44 which is fitted and connected to the crank pin 36.
It functions as a stopper plate to prevent it from coming off.

Such a holder plate 61 is located inward from its base 62, that is, above the crank web 35, and
It integrally has an extending portion 65 that extends sufficiently to the axis C of the crankshaft 30, and a pin hole 66 is bored in a portion of the extending portion 65 that coincides with the axis C of the crankshaft 30. A center pin 71 is inserted into this pin hole 66 from above, the lower end of the center pin 71 is caulked, and its axis c is made to coincide with the axis C, and the center pin 71 is fixed and erected on the extension part 65. There is.

Further, weight brackets 67, 6 are provided on the extending portion 65 at opposing positions with the center pin 71 interposed therebetween.
7 is erected, and the governor weight 7 is attached to these brackets 67, 67 with pivot pins 68, 68, respectively.
2 and 72 are pivotally supported, and a governor slider 74 is slidably mounted on the center pin 71 from above. At this time, governor slider 7
Push arms 73, 73, which are integrated with governor weights 72, 72, are in contact with the lower end surfaces of flanges 75 formed at the lower part of the flange 4, respectively, facing each other in the radial direction.

In this way, the governor device 60 is placed on the extending portion 65 of the holder plate 61 so that the axis c of the center pin 71 is aligned with the governor device 60.
was aligned with the axis C of the crankshaft 30 and mounted.

The pusher portion 76, which is the tip of the governor slider 74, faces the guide port 43a formed in the most bulging portion 43 of the plate 42 disposed above the pusher portion 76, and this pusher portion 76 is connected to the throttle of the carburetor. It is in contact with one end of the link mechanism 77. Further, the tip of the extending portion 65 of the holder plate 61 is bent upward to form an upright piece 69, and the extending portion 65 is bent upward.
An upright piece 64 is formed by making a notch at the boundary between the holder plate and the base 62 and bending it upward, and these opposing upright pieces 64 and 69 increase the rigidity of the holder plate extension 65.

As described above, the holder plate 61 of the governor device 60 is fixed to the end face of the crank pin 36 of the cantilever type crankshaft 30, and the axis c of the center pin 71 that slidably supports the governor slider 74 on the holder plate 61. Since the governor device 60 is mounted so that the axis C coincides with the axis C of the crankshaft 30, it is possible to make the governor device 60 rotate at the same high speed as the crankshaft 30 and achieve high performance. The governor device 60 can be placed using the space in the end face direction of the crank web 35 without requiring a power transmission mechanism or a separate shaft.

The base 62 of the holder plate 61 also has the advantage of serving as a stopper for preventing the connecting rod 44 fitted and connected to the crank pin 36 from coming off.

The present invention has many advantages as mentioned above.

Although the embodiment has been described as an engine with a vertically installed crankshaft, it is of course possible to use a horizontally installed crankshaft type engine.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal side view of the engine, and FIG. 2 is a longitudinal sectional front view thereof. In the drawing, 10 is the engine, 30 is the crankshaft, 36 is the crank pin, 44 is the connecting rod,
60 is a governor device, 61 is its holder, 71 is a center pin, 74 is a governor slider, C is an axis of the crankshaft, and c is an axis of the center pin.

Claims (1)

[Scope of claims for utility model registration] (1) In a crankshaft cantilever engine,
The holder of the governor device that controls the throttle of the carburetor is fixed to the end face of the crank pin of the crankshaft, and the holder is extended to the axis of the crankshaft, and the axis of the center pin that slidably supports the governor slider is connected to the crankshaft. A governor device for a crankshaft cantilever engine, characterized in that the governor device is mounted on the holder so as to be aligned with the axis of the shaft. (2) The governor for a crankshaft cantilever engine according to claim 1 of the utility model registration, wherein the holder also serves as a stopper for preventing a connecting rod that is fitted and connected to the crank pin from coming off. Device.