JPS60136641A - Balancer device of reciprocating engine - Google Patents

Abstract

PURPOSE:To offer a compact balancer device by providing a crank shaft with a rotor bearing eccentric to the crank shaft axis and also providing around the rotor bearing with a reciprocating portion bearing eccentric to the rotor bearing and making the reciprocating portion bearing support a counterweight to perform an opposite reciprocating motion to the piston. CONSTITUTION:On the outer portions of crank webs 7, 7 of a crank shaft 5 eccentric pins 11, 11 are provided adjacent to and in a body with each web 7, and on the outer periphery of each eccentric pin 11 a rotor bearing 12 is formed. On each rotor bearing 12 an eccentric plate 13 is rotatably bearing supported and on the outer periphery of said eccentric plate 13 an reciprocating portion bearing 14 is arranged. To the reciprocating portion bearing 14 a counterweight 15 is supported and the counterweight 15 is slidably fitted to a guide pin 16 provided in parallel to the shaft center axis of a cylinder 1 and is guided so as to make reciprocating motion.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a balancer device for a reciprocating engine, such as a reciprocating internal combustion engine, which converts external force applied to a piston into rotational force via a crank mechanism.

[Prior art]

In this type of reciprocating engine, especially a reciprocating internal combustion engine that rotates at high speed, vibration occurs due to the inertia force and moment of inertia of the mass of the reciprocating part such as the piston, so various parancer devices are used to suppress this vibration. Or proposed.

For example, a system in which a balance shaft having a balance weight is supported in parallel with a crankshaft and rotated by the crankshaft is used.

However, this method has the disadvantage that a moment is generated between the crankshaft and the balance shaft, and it is not possible to achieve sufficient balance, and therefore, vibration cannot be sufficiently suppressed.

As a means for eliminating the moment of the above-mentioned method, a method has been proposed in which a pair of balance shafts are provided sandwiching the crankshaft, as described in, for example, Japanese Utility Model Publication No. 52-32802. In this case, both balance shafts are rotated via a gear mechanism at the same speed and in the opposite direction as the crankshaft, and each balance shaft is configured to share a weight that is inversely proportional to its distance from the crankshaft.

However, in such a balancer device, the balance shaft is placed on both sides of the crank web, so
The disadvantage is that the structure becomes complicated and the volume and weight also increase considerably.

Further, in US Pat. No. 3,457,804, a counterweight with an arm is suspended from an eccentric journal provided on a crankshaft, and the counterweight is supported at the tip of a link pivotally supported on a side wall of the crankcase. A parantor device of the structure is described.

However, in such a structure, the counterweight moves up and down while moving in a direction perpendicular to the cylinder axis, and a force exceeding the inertia of the reciprocating part such as the piston is generated on the counterweight, resulting in this imbalance. The disadvantage is that vibration cannot be sufficiently reduced due to the force.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the prior art described above and to provide a palancer device for a reciprocating engine that has a continuous structure and can eliminate unbalanced forces in the reciprocating section.

A feature of the present invention is to achieve the above object by providing a reciprocating part bearing corresponding to the small end bearing part around the rotating part bearing corresponding to the big end bearing part, and supporting a balance weight with the reciprocating part bearing. It is to be.

[Structure of the invention]

That is, according to the present invention, in a palancer device for a reciprocating engine that converts external force received by a piston into rotational force via a crank mechanism, a rotating part bearing eccentric to the crankshaft is provided, and the rotating part bearing is provided eccentrically from the crankshaft. A reciprocating device characterized in that a reciprocating portion bearing eccentric to the bearing is provided around the bearing, a counterweight is supported by the reciprocating portion bearing, and the reciprocating movement of the counterweight is set in the opposite direction to the reciprocating movement of the piston. A parsor device for a moving engine is provided.

〔Example〕

FIG. 1 and FIG. 2 are diagrams showing an embodiment in which the present invention is applied to an internal combustion engine, and the present invention will be specifically explained below with reference to these drawings.

In FIG. 1, a piston 2 fitted into a cylinder 1
is connected to a small end of a moving connecting rod 4 by a piston pin 3, and the large end of the connecting rod is connected to a crank pin 6 of a crankshaft 5. The crank bin 6 has a pair of crank webs (
The crank arm) 7°7 is integrated with the crankshaft 5. The dashed line O indicates the axis of the crankshaft 50, that is, the crank center, and the crankshaft is connected to the main bearing 8.
and is supported within the shift flank case 10 by a bearing portion 9.

The above is the configuration of a general internal combustion engine, and during operation, the top surface of the piston 2 receives the gas emitted from the combustion chamber (external force), and the resulting forward movement of the piston is transferred to the connecting rod 4 and the crankshaft. It is converted into rotational force (crankshaft rotational force) by a crank mechanism consisting of 5 and the like. Note that FIG. 1 shows a state in which the piston 2 is at the bottom dead center.

2 and 2, eccentric bins 11, 117>E are integrally provided adjacent to the outer portion of each crank web 7.7 of the crankshaft 5,
Rotating part bearings 12.degree. 12 are formed on their outer peripheries. The center 01 of this rotating part bearing is eccentric from the crank center 0 by h.

An eccentric plate 13 is rotatably supported on each rotating part bearing 12, and a reciprocating part bearing 14 is formed on the outer periphery of the eccentric plate. The center 02 of this reciprocating part bearing is il) The rotating part bearing 1
Center 0 of 2! More t! The distance is eccentric.

In this way, a pair of reciprocating portion bearings 14.14 provided adjacent to the side surfaces of the crank web 7.7 are provided with a counterweight 15.
is supported. This counterweight 15 is the first
As shown in the figure, it has a substantially mouth shape when viewed from the front, and is supported by the reciprocating portion bearings 14 at both side wall portions.

The counterweight 15 is provided parallel to (including concentrically with) the axis of the sill 1, and is slidably fitted into the bin 16 and guided to reciprocate (up and down). However, the idle bin 16 is installed in a portion of the crankcase opposite to the piston 2 with respect to the crankshaft.

In the illustrated example, a guide bin 17 parallel to the cylinder axis is fixed to an upper end protrusion 15A of one wall of the counterweight 15, and a guide hole or guide groove 18 formed in the fixing part includes the guide bin 17. Another reciprocating guide means is constituted by a slidable fit therein.

The rotating part bearing 12 constitutes a so-called large end bearing part, and the reciprocating part bearing 14 constitutes a so-called small end bearing part 'f. It is connected to the crankshaft 5 by a crank mechanism having a diameter of .4.

Therefore, crank center 0 (axis center of crankshaft 5)
The eccentric direction of the rotating part bearing 12 and the eccentric direction of the crank bin 6 are set to be opposite to each other, and the reciprocating part bearing 14 is set to be opposite to the eccentric direction of the rotating part bearing 12 relative to the center o1 of the rotating part bearing 12.
The center (center of the eccentric plate 13) 02 is located on a straight line extending from the crank center O in the opposite direction to the piston 2, and on the center 0. It is set at a distance tl from .

Therefore, in comparison with a crank mechanism between reciprocating machines, the counterweight 15 has a crank radius rl with respect to the crankshaft 5, a connecting rod length, and a distance between the centers of the large end and the small end) t.
This results in a reciprocating motion similar to that of the piston connected by the crank mechanism of t. However, counterweight 1
5 moves in the opposite direction to the piston, that is, when the piston moves toward the top dead center, it moves toward the bottom dead center.

In Fig. 1, the crank radius and the length of the connecting rod of the engine are indicated by r and t, respectively, and in a normal internal combustion engine, the ratio of the length of the connecting rod to the crank radius, that is, the connecting rod crank ratio λ- The value of 1/r is within the range of 2-3.

According to the balancer device described above with reference to FIGS. 1 and 2, the overall external dimensions of the engine can be increased without increasing
Unbalanced forces caused by the weight of reciprocating parts such as pistons can be almost completely eliminated.

In other words, with conventional balancer devices, when attempting to eliminate the unbalanced force of the weight of the reciprocating section, the engine external shape becomes abnormally large in dimension, so the unbalanced force has to remain within a range that has no effect. According to the structure of the embodiment described above, such problems can be easily solved. The reason is explained below.

The unbalanced force of a single cylinder, that is, the reciprocating inertia force up to the sixth order is expressed by the following equation.

W 1 1, 'r 1'' (CQ9213 +7cm2''~, i
Ts cts 4 ”112823-Naki6θ)...
...(1) Here, W is the reciprocating part equivalent type %, g is the gravitational acceleration, r is the crank radius, ω is the angular velocity, θ is the crank angle 1 [λ is the connecting rod crank ratio (the connecting rod length t and the crank radius (L/r).

Therefore, in order to eliminate this unbalanced force, the first
It is sufficient to increment the following relationship in the structure of FIG. 2 and FIG.

W (X r 1 = W X r --(2) That is, the value of WXrO and the value of λ may be made the same for the piston 2 and the counterweight 15, and the piston 2 and the counterweight 15 may be moved back and forth oppositely.

If such a relationship is satisfied, all order terms in equation (1) can be completely canceled, and perfect balance of the moving parts can be achieved.

According to the structure shown in FIGS. 1 and 2, since the living portion bearing 14 is provided around the rotating portion bearing 12, W can be set to the same value, thereby almost completely eliminating the inertial force (unbalanced force) caused by the mass of the piston and connecting rod, and achieving a nearly ideal balance state. can. In this way, the vibration and noise levels of the reciprocating engine can be significantly reduced, and furthermore the wear on the moving parts can also be reduced.

Although the above embodiment describes the case where the present invention is applied to a reciprocating internal combustion engine, the present invention is applicable to any type of engine that converts reciprocating motion into rotational motion, including reciprocating external combustion engines such as steam engines. It can be applied to all types of institutions.

Further, the present invention can be similarly applied to a multi-cylinder engine.

〔Effect of the invention〕

As is clear from the above description, the present invention provides a palancer device for a reciprocating engine that can almost completely eliminate the inertia of the reciprocating part.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing one embodiment of a parsor device for a reciprocating engine according to the present invention, and FIG. 2 is a partial cross-sectional view (ill 1 side view) taken from NHU in FIG. 1. ... Cylinder, 2... Piston, 4... Connecting rod, 5... Crankshaft, 6... Crankbin, 10...
... Crank case, 11 ... Eccentric bin, 12 ... Rotating part bearing, 13 ... Eccentric plate, 14 ...
・Reciprocating part bearing, 15... Counterweight, 16...
・Idobin, 17...Guide bin, W...Significant responsibility of the former part of the engine, W,...Counterweight weight,
r...crank radius, t...length of connecting rod, r1 eccentricity of rotating part bearing, 1,...distance between centers of rotating part bearing and scooping part bearing. Figure 1 Figure 2

Claims (2)

[Claims] (1) In an iZ lancer device for a reciprocating engine that converts external force received by a piston into rotational force via a crank mechanism, a rotating part bearing eccentric to the crankshaft is provided, and a rotating part bearing is provided around the rotating part bearing. A noq lancer for a reciprocating engine, characterized in that a reciprocating section bearing is provided eccentrically, a counterweight is supported by the reciprocating section bearing, and the reciprocating motion of the counterweight is set in the opposite direction to the reciprocating motion of the piston. Device. (2) The eccentricity of the rotating part bearing with respect to the crankshaft is rls the distance L between the center of the rotating part bearing and the center of the column bearing. , the weight of the counterweight is W11
When the crank radius of the reciprocating engine, the distance between the large end and the small end, and the equivalent weight of the reciprocating part are r, t, and W, respectively, the following relationship should be established: Wl X r 1 L; W X r '1-4 rl r Claim 1 characterized by
A parsor device for a reciprocating engine as described in .