KR19980062825A - Automatic Timing Belt Tension - Google Patents

Abstract

The present invention relates to a timing belt tension automatic maintenance device that applies tension to a timing belt that transmits a driving force from a crankshaft to a cam shaft in an engine of an automobile, thereby preventing a decrease in power transmission efficiency of the timing belt. The present invention connects a crankshaft pulley installed on a crankshaft and a camshaft pulley provided on a camshaft, and applies a tension to a timing belt that transmits the rotational force of the crankshaft pulley to the camshaft pulley to increase power transmission efficiency. An idle pulley fixedly installed in contact with the tight side of the belt; A tension pulley circumscribed to the relaxed side of the timing belt opposite to the idle pulley, the tension pulley being configured to allow relative movement with respect to the idle pulley; In the automatic timing belt tension holding device including a tension means for pulling the tension pulley toward the idle pulley to form a tension on the timing belt, the idle pulley is installed to enable the lateral movement, the tension means is the tension pulley And an idle pulley are connected and simultaneously pulled in the direction in which the tension pulley and the idle pulley are in contact with each other to generate an even tension over the entire length of the timing belt.

Description

Automatic Timing Belt Tension

The present invention relates to a timing belt tension automatic device for applying a tension to a timing belt that transmits a driving force from a crankshaft to a cam shaft in an engine of an automobile, thereby preventing a decrease in power transmission efficiency of the timing belt.

[0003] In an engine of an automobile, an engine of an overhead cam type, in which a cam, which is a valve opening and closing mechanism of a combustion chamber, is disposed on a cylinder head, has a cam shaft from a crank shaft and a timing belt (crank shaft). While rotating under the power transmitted through the Timing Belt, the eccentric cam integrally installed on the crankshaft has an intake / exhaust valve opening / closing structure for opening and closing the intake valve and the exhaust valve.

Figure 1 of the accompanying drawings is a front view showing the power transmission structure from the crankshaft to the camshaft in the above-described intake and exhaust valve opening and closing structure.

As shown, the intake / exhaust opening / closing structure is disposed at the bottom and a crank shaft pulley (1) installed at the end of the crankshaft (not shown) for converting the reciprocating motion of the piston into a rotary motion, and the crank Cam shaft pulleys (2) and the crankshaft pulleys (1) and cams at the ends of two cam shafts (not shown) spaced upwardly from the shaft pulley (1) and symmetrically arranged on top of the cylinder head. And a timing belt 3 or the like for interlocking the shaft pulley 2.

In such a configuration, as the crankshaft pulley 1 rotates clockwise, the cam shaft 2 rotates to rotate an internal cam (not shown) to open and close the intake / exhaust valve.

On the other hand, in the intake / exhaust opening and closing structure having the above-described configuration, as shown in the illustrated example, when the timing belt 3 is loosened, the driving force of the crankshaft pulley 1 is properly transmitted to the tension pulley 4. In order to prevent such a phenomenon, the timing belt tension automatic maintenance device is provided which generates tension to tighten the timing belt 3.

The timing belt tension automatic maintenance device is divided into a type for setting only the initial tension and an automatic adjustment type for automatically maintaining the relaxed tension of the timing belt tension automatic maintenance device at a constant tension during operation. Self-adjusting timing belt barrier automatic retainer.

In the illustrated example, the automatic timing belt tension retaining device includes a tension pulley 4 in contact with an outer surface of the timing belt 3, an idle pulley 5 symmetrically installed on the tension pulley 4, and the tension pulley ( It consists of a tension spring (6) for applying a tensile force to 4).

In such a configuration, the tension spring 6 pulls the tension pulley 4 toward the idle pulley 5 to tighten the left side of the timing belt 3 on the loose side 3a of the timing belt 3. The frictional force of the friction surface between (3) and the surfaces of each pulley (4, 5) is increased to increase the driving efficiency of the crankshaft pulley (1) with respect to the cam shaft pulley (2).

By the way, since the conventional timing belt tension automatic maintenance device as described above generates tension only on the relaxed side 3a of the timing belt 3, the friction force between the timing belt 3 and the pulleys 4 and 5 is reduced. Not only does not shorten the life of the timing belt 3, but also had problems such as noise generated by the non-uniform friction.

The present invention solves the problems of the conventional timing belt tension automatic maintenance device as described above. The tension between the pulley and the timing belt is made constant by generating tension on both the tight and loose sides of the timing belt. It is an object of the present invention to provide a timing belt tension automatic maintenance device which can extend the life of a timing belt and can suppress the generation of noise due to the difference in friction between each pulley and the belt.

1 is a front view showing the structure of a conventional timing belt tension automatic maintenance device.

Figure 2 is a front view showing the structure of the automatic timing belt tension maintaining apparatus according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

1: crankshaft pulley 2: camshaft pulley

3: timing belt 3a: relaxed side

3b: Tight side 4: Tension pulley

5: idle pulley 7: tension spring

8: damper

The timing belt tension automatic maintenance device of the present invention for achieving the above object, by connecting the crankshaft pulley installed on the crankshaft and the camshaft pulley provided on the camshaft, the timing for transmitting the rotational force of the crankshaft pulley to the camshaft pulley An idle pulley that is fixed to the tight side of the timing belt to increase power transmission efficiency by applying tension to the belt; A tension pulley circumscribed to the relaxed side of the timing belt opposite to the idle pulley, the tension pulley being configured to allow relative movement with respect to the idle pulley; In the automatic timing belt tension holding device including a tension means for pulling the tension pulley toward the idle pulley to form a tension on the timing belt, the idle pulley is installed to enable the lateral movement, the tension means is the tension pulley And the pulley is connected between the pulley and the pulley at the same time characterized in that the pulley in the direction in which the pulley.

On the other hand, the tension means is preferably an elastic spring or the elastic spring and the damper directly connected to each other.

EXAMPLE

Hereinafter, a preferred embodiment of the present invention having the configuration as described above will be described in detail with reference to the accompanying drawings.

In describing the present embodiment, the same reference numerals are used for the configurations of the present invention that are the same as the prior art described at the outset, and only the parts that have been improved without doubling as possible for the sake of clarity will be mainly described.

2 is a front view showing the structure of the automatic timing belt tension maintaining apparatus according to an embodiment of the present invention.

As shown, the timing belt tension automatic maintenance device of the present embodiment has a structure in which the tension pulley 4 and the idle pulley 5 are directly connected by the tension spring 7 and the damper 8 as the tension means. The idle pulley 5, like the tension pulley 4, is installed in a lateral movable manner, unlike the conventional timing belt tension automatic maintenance device.

In such a configuration, the tension pulley 4 and the idle pulley 5 are pulled by a force of the same magnitude in the direction in which they are in contact with each other, and the timing belt generated by the pulleys 4 and 5 in the timing belt 3. The relaxed side 3a and the tight side 3b of (3) have the same magnitude of tension. Therefore, the magnitude of the tension generated in the timing belt 3 becomes the same as a whole, and as a result, the frictional forces in the pulleys 4 and 5 become the same in size, thereby suppressing the occurrence of noise due to the imbalance of the force. Further, the tension is evenly distributed on the timing belt 3 with the same size irrespective of the relaxed side 3a and the tight side 3b, thereby extending the life of the timing belt 3.

According to the present invention as described in detail above, not only can significantly reduce the noise generated in the intake / exhaust opening / closing structure controlled by the timing belt tension automatic maintenance device during operation, but also uniformly distributes the tension over the entire length of the timing belt. By distributing, the life of the timing belt can be extended.

On the other hand, the present invention is not limited to the preferred embodiments of the above-described features, and various modifications can be made by those of ordinary skill in the art without departing from the gist of the invention claimed in the claims. Would be possible.

Claims (1)

Tightening the timing belt by connecting the crankshaft pulley installed on the crankshaft and the camshaft pulley installed on the camshaft to increase the power transmission efficiency by applying tension to the timing belt that transmits the rotational force of the crankshaft pulley to the camshaft pulley. An idler pulley fixedly installed in contact with; A tension pulley circumscribed to the relaxed side of the timing belt opposite to the idle pulley, the tension pulley being configured to allow relative movement with respect to the idle pulley; In the automatic timing belt tension holding device including a tension means for pulling the tension pulley toward the idle pulley to form a tension on the timing belt, the idle pulley is installed to enable the lateral movement, the tension means is the tension pulley And pulling between the idle pulley and simultaneously pulling the tension pulley and the pulley in the direction in contact with the idle pulley.