JPS637734Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement of a composite pulley used for driving auxiliary machinery in an engine, for example.

(Prior art) The crankshaft of an automobile engine is equipped with a pulley that drives the always-equipped auxiliary equipment such as an alternator and water pump. A pulley is provided for driving so-called optional auxiliary equipment such as a pump. In that case,
The former pulley is generally made of highly rigid cast iron, while the latter pulley is made of sheet metal in order to be lightweight or to be easily attached and detached when necessary. It is customary to do so. However, since sheet metal pulleys do not have sufficient rigidity, they are susceptible to vibrations in the axial direction, especially at the outer periphery, due to torsional vibrations of the crankshaft and belt vibrations caused by engine torque fluctuations, and this vibration generates radiated sound. There is a drawback.

By the way, as a solution to the above-mentioned problems, there is a device related to a ``crank pulley for an internal combustion engine'' disclosed in, for example, Japanese Utility Model Application Publication No. 18031/1983. As shown in Fig. 1, this invention provides an elastic member 3 between a cast iron pulley 1 (inner pulley in the above publication) and a sheet metal pulley 2 (outer pulley), and prevents the vibration of the sheet metal pulley 2. This is intended to be suppressed by converting it into thermal energy due to friction with the elastic member 3. However, according to this invention, since the elastic member 3 is required separately, the number of parts and the number of assembly steps increase, resulting in a problem that the cost becomes high.

(Purpose of the invention) The present invention deals with the above-mentioned problems in the conventional art. When a composite pulley consisting of a sheet metal pulley is provided, and a damper pulley formed by connecting an inner member and an outer member via an elastic member is used as the former pulley, the elastic member of the damper pulley can be effectively used. The purpose of this is to reduce the sound emitted from the sheet metal pulley without providing a separate elastic member.

(Structure of the invention) The invention is structured as follows to achieve the above purpose.

That is, a damper pulley is formed by integrating an outer member having an engaging groove formed on the outer periphery to engage with the first belt and an inner member fixed to the rotating shaft through an elastic member, and a damper pulley having a first belt on the outer periphery. In the composite pulley, the end portion of the elastic member of the damper pulley is connected to the inner member and the outer member. It is configured to protrude from the end face of and come into contact with a sheet metal pulley located on the side thereof. This elastic member suppresses the axial vibration of the sheet metal pulley and reduces the generation of sound radiated from the pulley.

(Effects of the invention) According to the above configuration, the sound radiated from the sheet metal pulley in the composite pulley can be reduced without increasing the number of parts or assembly man-hours, and therefore without increasing costs. In particular, if the present invention is applied to a composite pulley provided on the crankshaft of an engine, a quiet engine can be realized.

(Example) The present invention will be described below based on an example shown in the drawings.

As shown in FIG. 2, sprockets 13, 14, and 15 are installed in the crankcase 12 at the end of the crankshaft 11 of the engine 10 opposite to the end to which the transmission (not shown) is connected. In addition, a chain 18 that drives an oil pump 17 installed in an oil pan 16 is attached to the sprocket 13, and a chain 18 that drives an oil pump 17 installed in an oil pan 16 is also attached to the sprocket 13.
5 is a chain 1 that drives a camshaft (not shown).
9 and 20 are respectively multiplied. Further, a composite pulley 21 is attached to the end of the crankshaft 11 outside the crankcase 12.
As shown in an enlarged view in FIG. 3, this composite pulley 21 includes a first pulley 22 for driving auxiliary equipment such as an alternator and water pump, which is always installed in the engine 10, and a first pulley 22 which is installed as an option, for example, for driving auxiliary equipment such as an alternator and a water pump. It is composed of a second pulley 23 for driving auxiliary equipment such as an air conditioner compressor and a power steering pump. As the first pulley 22, a damper pulley consisting of an inner member 24, an outer member 25, and an elastic member 26 that connects both members 24 and 25 is used. The outer member 25 is fixed to the crankshaft 11 with a bolt 28 while being prevented from rotating, and a belt 29 for driving the alternator and the like is engaged with a engagement groove 25a formed on the outer periphery of the outer member 25. On the other hand, the second pulley 23 is a pulley made of sheet metal, and its center portion is connected to the inner member 24 of the damper pulley 22 with a plurality of bolts 30...
30, and a belt 31 for driving the compressor, etc., is engaged with the engagement groove 23a formed on the outer periphery.

Therefore, the elastic member 26 of the damper pulley 22 has an end portion 26 as shown by the chain line in FIG.
a is the end surface 24 of the inner member 24 and the outer member 25
a, 25b so as to protrude toward the sheet metal pulley 23 side, and when the sheet metal pulley 23 is attached, the surface 23b of the pulley 23 is shown as a solid line.
It is configured to be pressed into contact with the

Next, the operation of this embodiment will be explained.

The crankshaft 11 of the engine 10 is intermittently subjected to explosive force, causing it to torsionally vibrate, which causes a damper pulley 22 attached to the end of the shaft 11 to
and is transmitted to the sheet metal pulley 23. In that case, in the damper pulley 22, the inner member 2
4 and the outer member 25
6 reduces the transmission of vibration from the inner member 24 to the outer member 25, or the inertial rotation of the outer member 25 acts to suppress rotational vibration of the inner member 24 or the crankshaft 11.

On the other hand, since the sheet metal pulley 23 does not have sufficient rigidity and is only fixed at the center, the outer circumference especially resonates in the axial direction due to the above-mentioned torsional vibrations and vibrations from the belt 31. It's in easy condition. However, the elastic member 26 of the damper pulley 22 is provided on one surface 23b of the pulley 23.
Since the end portion 26a of the pulley 23 is pressed against the
The vibrations are absorbed or suppressed by the elastic member 26. Thereby, the radiated sound due to the vibration of the sheet metal pulley 23 is reduced.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of a conventional composite pulley;
FIG. 2 is a partially cutaway side view of the vicinity of a composite pulley in an engine showing an embodiment of the present invention, and FIG. 3 is an enlarged vertical sectional view of the composite pulley. DESCRIPTION OF SYMBOLS 11... Rotating shaft (crankshaft), 21... Composite pulley, 22... Damper pulley, 23... Sheet metal pulley, 24... Inner member, 25... Outer member, 26... Elastic member, 29, 31 ……belt.

Claims (1)

[Scope of utility model registration request] A damper pulley comprising an outer member having an engaging groove formed in its outer circumferential portion for engaging a first belt, and an inner member fixed to an end of a rotating shaft, and an elastic member interposed between the two members. A pulley made of sheet metal, which is provided opposite to the damper pulley and has an engaging groove formed in its outer periphery in which a second belt that drives a driven member different from the driven member driven by the first belt engages. 1. A composite pulley, characterized in that end portions of elastic members protruding from end faces of inner and outer members of the damper pulley are brought into contact with the sheet metal pulley.