JPS6117740A - Reciprocative engine - Google Patents

Abstract

PURPOSE:To accomplish an engine with low vibration by arranging cylinders with different dias. in series, and by eliminating the inertia force and inertia moment to be generated by the weight of reciprocating part so far as calculated output is concerned. CONSTITUTION:If the engine has three cylinders in series, for example, No.1 and 3 cylinders 1, 3 are given the same dia. while No.2 cylinder 2 is made in a diameter 2-1/2 as large as the abovementioned. Thereby the weight of reciprocating part of No.2 cylinder 2 can be comparatively easily decided to the amount equal to the sum of No.1 and 3 cylinders 1, 3. Thus the engine is free from generation of inertia force and moment.

Description

[Detailed description of the invention] The present invention relates to a reciprocating engine.

The inertial force and inertial couple generated by the reciprocating partial weight in a so-called resin zero-mouth engine are expressed by the following equations (6) and (7) for a series engine.

(1) Determine the inertia force generated by the reciprocating partial mass of the single-cylinder engine with reference to FIG. In fig.

θ: rotation angle of the crankshaft, z: direction of inertial force, upward is positive. r: crank radius, t: connecting rod length, λ=r/L, ω: rotational angular velocity of the crankshaft, and the displacement, velocity, and acceleration of the piston are shown below.

Displacement X='r [(1-possible θ)+4-(1-plot)]...
(1) Expanding the series to each order and organizing it: X = rω2 Σq i button θ
Mountain...Yu・River...(4) i=1 Hani9,1=□1,2:λ+y+Shidan, λ33λ5 q3=o・ q4°=4− 」 9λ5 q5=0・q6"" 128 Therefore, the first inertial force due to the mass m of the reciprocating part is as follows.

F7. ,=m'r'ω"ql(IllSjθ=...-=
-(5) (2) Find the vertical inertia force F2 of the series engine and the y-axis rotational couple My with reference to FIGS. 2(a) and (b).

In the figure, θ is the rotation angle of the first crank, with clockwise rotation being positive when viewed from the front. αj: Phase of the third crank relative to the first crank, 2j: Distance (X coordinate) from the crank center to the third crank.

The vertical primary inertia force Fzi is obtained by combining equation (5) for a single-cylinder engine.

FZ l ”” m' r ・O) 2q iΣcas
i (θ ten αj) −−・・−・−(6) Co 1 Around the y axis, the primary couple is calculated by considering the distance tj in equation (6).

Myi2m'r'ω2qlΣtjcost(θ+αj)
−1・=−(7) J=1 The inertial force and inertial couple shown in the above equations (6) and (7) are as follows.

It is known that no matter how many cylinders there are, or even if the cylinder arrangement is changed to a square arrangement (9), it cannot be overcome.

In fact, it is well known that Regisoro engines have the disadvantage of large vibrations. In addition, there are cases where a so-called parancer is installed on the exterior to prevent vibration, but it is expensive and the reduction effect is not perfect.

An object of the present invention is to provide a reciprocating engine that can eliminate the above-mentioned drawbacks with a simple structure, and its feature is that cylinders with different diameters are arranged in series.

In this case, the inertial force and inertial couple caused by the weight of the reciprocating part can be calculated to be completely zero.

The present invention can be applied to engines, consoles, and pumps.

FIG. 3(a) is a front view showing a three-cylinder engine according to an embodiment of the present invention, and FIG. 3(b) is a perspective view thereof.

In the figure, 1 is the first cylinder, 2 is the second cylinder, 3 is the third cylinder, and 4 is the crankshaft.

1st. The third cylinder is in the same phase, and the second cylinder is out of phase by 180 degrees. The coordinate system and symbols are the same as above.

First, the vertical primary inertia force Fzi is applied to equation (6).

F,,=rω2qiΣmjcosi(θtenαj)j=1 =m1rω2qicos(io)+m2rω2qico
si(θ+π) 10m3rω2q 1cos(if)'
.

-(m, 10m3m2) 1'ω2qico
s(io) ・・・・・・・・・・・・・・・(6
') Next, for the i-th couple around the y-axis, let the distance between the parts be t,
Apply to equation (7).

My1= m, rω2qiAcos(io)−m3rω
2q 1deas (io) ・-・・-(7') Here, if we set + ml + m3 = m2 and ml-m3, obviously (6'), (7')
From the formula, F, = My, = 0, and the inertial force and inertial couple can be completely zero in all orders.

For example, in an in-line three-cylinder engine, if the first and third cylinders are made the same diameter, and the second cylinder is made six times the diameter, it is relatively easy to reduce the weight of the reciprocating portion of the second cylinder to the first. It is possible to set it so that it is the sum of the third cylinders, and it is possible to set the cylinder so that it is the sum of the third cylinders, and it can be set as an engine in which no inertial force or inertial couple occurs. In addition, by setting the second cylinder to 0 times that of the first and third cylinders, if the gas pressure in each cylinder is the same, it is possible to obtain an extremely low-vibration engine with torque fluctuations on the same level as a two-cylinder engine. . In addition.

Although an example of an in-line three-cylinder system is shown here, an example of a multiple-cylinder system is also conceivable.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing a single cylinder engine, Fig. 2 (,) is a front view showing an in-line engine, and Fig. 2 (b) is a perspective view thereof.
FIG. 3(,) is a front view showing a three-cylinder engine according to an embodiment of the present invention, and FIG. 3(b) is a perspective view thereof. 1.2.3...Cylinder, 4...Crankshaft. 1 ′ ′A=1 Figure 2 (0) 2nd paragraph (P) (Q)
(1)) #3 Figure

Claims (1)

[Claims] 1. A reciprocating engine characterized by cylinders having different diameters arranged in series.