JP2009103265A - Power transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power transmission device reduced in the size and weight, while smoothly transmitting motive power by damping vibration of a rotary shaft. <P>SOLUTION: In this power transmission device 1, a pulley 2 installed on a crankshaft 11 includes a viscous coupling 21. This viscous coupling 21 has a hub 22 fixed to the crankshaft 11, a housing 23 containing the hub 22 and rotatable to the hub 22, a viscous fluid filled between these hub 22 and housing 23, a plurality of inner plates 27 arranged in the viscous fluid and rotating together with the hub 22, and an outer plate 28 alternately arranged superposing with the inner plates 27 in the viscous fluid and rotating together with the housing 23. An outer peripheral surface 23a of the housing 23 is formed as an engaging surface with pulleys 3, 4, 5 and 6 installed on the rotary shaft of an auxiliary machine. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a power transmission device that transmits a driving force of an input-side rotating shaft to an output-side rotating shaft.

  In vehicles such as automobiles, the driving force of the crankshaft of the engine is transmitted to auxiliary machines such as alternators, air compressors, steering pumps, water pumps, etc. via pulleys, belts and gears, and these auxiliary machines are driven. Yes. Torsional vibrations occur in the crankshaft due to torque fluctuations, etc., but this torsional vibrations, for example, excite the above-mentioned auxiliary machine to cause resonance, causing unpleasant noise and vibrations.

  Therefore, a torsional damper is attached to the crankshaft to suppress torsional vibration of the crankshaft so that power is smoothly transmitted to the auxiliary machine. Rubber dampers and viscous dampers are known as torsional dampers.

  For example, when the driving force of the crankshaft is transmitted by a pulley and a belt, the rubber damper divides the pulley into a hub fixed to the crankshaft and a pulley portion around which the belt is wound, and a rubber is interposed between the two. Configured.

  The viscous damper includes an annular housing fixed to the crankshaft and an inertia ring that can rotate freely inside the housing, and a viscous fluid such as silicon oil is filled between the housing and the inertia ring. The inertial ring rotates in the opposite direction relative to the torsional vibration of the crankshaft. The energy of the crankshaft vibration is replaced by the energy of the relative rotation of the inertia ring and the thermal energy due to shearing of the viscous fluid between the inertia ring and the housing, thereby suppressing the torsional vibration of the crankshaft.

The above-mentioned viscous damper suppresses the torsional vibration of the crankshaft with a single inertia ring, but suppresses the torsional vibration of the crankshaft by using a viscous coupling having a plurality of plates that cause shearing of the viscous fluid. The thing which did it is also known (for example, refer patent document 1).
JP 2005-98399 A

  In general, a rubber damper exhibits vibration damping only at a specific frequency, whereas a viscous damper exhibits vibration damping at a wider frequency range. However, in the above-mentioned viscous damper that suppresses crankshaft vibration with a single inertia ring, the vibration suppression performance depends on the contact area between the inertia ring and the viscous fluid and the weight of the inertia ring. Attempting to do so results in an increase in weight and size of the inertia ring. On the other hand, since the thing using the viscous coupling disclosed by patent document 1 can earn a contact area with a viscous fluid with a several plate, it avoids the enlargement of each plate, weight Can be suppressed.

  However, in patent document 1, the gear and the viscous coupling which transmit motive power are arranged in parallel in the axial direction of the rotating shaft. For this reason, if the viscous coupling is included, the power transmission device may become large, and there is a concern about an increase in weight between the gear and the viscous coupling.

  The present invention has been made in view of the above-described circumstances, and can provide a power transmission device that can smoothly transmit power by damping a rotating shaft and that is reduced in size and weight. Objective.

Said objective is achieved by the power transmission device as described in the following (1)-(3).
(1) Power that includes a pair of rotation transmitting elements that are respectively attached to the input-side rotation shaft and the output-side rotation shaft and engage with each other, and that transmits the rotation of the input-side rotation shaft to the output-side rotation shaft. A transmission device, wherein the viscous coupling is filled between a hub fixed to the rotating shaft, a housing containing the hub and rotatable with respect to the hub, and the hub and the housing. A viscous fluid, a plurality of inner plates arranged in the viscous fluid and rotating with the hub, and an outer plate arranged alternately in the viscous fluid with the inner plates and rotating with the housing. A power transmission device comprising: an outer peripheral surface of the housing of the viscous coupling as an engagement surface with the rotation transmission element on the other side.
(2) The power transmission device according to (1), wherein the rotation transmission element is a pulley in which a power transmission belt is wound around an outer peripheral surface and engages with each other via the belt.
(3) The power transmission device according to (1), wherein the rotation transmission element is a gear having teeth formed on an outer peripheral surface thereof and meshing with each other.

  According to the power transmission device of the present invention, the viscous fluid is sheared by the plurality of inner plates and outer plates of the viscous coupling to suppress torsional vibration of the rotating shaft. Since the contact area with the viscous fluid can be obtained with a plurality of plates, it is possible to avoid an increase in the size of each plate, suppress an increase in weight, and improve vibration damping. The viscous coupling and the rotation transmission element are integrated with the outer peripheral surface of the housing of the viscous coupling as an engagement surface of the rotation transmission element. Thereby, further reduction in size and weight can be achieved.

  Hereinafter, preferred embodiments of the power transmission device of the present invention will be described with reference to the drawings. 1 is a diagram showing a schematic configuration of an embodiment of a power transmission device according to the present invention, FIG. 2 is a plan view showing a rotation shaft of a prime mover and a rotation transmission element attached to the rotation shaft, and FIG. 3 is a rotation diagram of FIG. It is sectional drawing which expands and shows a transmission element.

  As shown in FIG. 1, the power transmission device 1 according to the present embodiment uses, for example, a driving force of an engine crankshaft to rotate an auxiliary machine such as an alternator, an air compressor, a steering pump, and a water pump in a vehicle such as an automobile. It is transmitted to the shaft. A pulley as a rotation transmission element is attached to each of the crankshaft and the rotating shaft of the auxiliary machine, and the pulley of the crankshaft and the rotating shaft of each auxiliary machine are engaged with each other via a belt. . In the figure, reference numeral 2 denotes a pulley attached to the crankshaft, reference numeral 3 denotes a pulley attached to the rotating shaft of the alternator, reference numeral 4 denotes a pulley attached to the rotating shaft of the air compressor, and reference numeral 5 denotes A pulley attached to the rotating shaft of the steering pump is shown. Reference numeral 6 denotes a pulley attached to the rotating shaft of the water pump. Reference numeral 7 denotes a belt connecting the pulley 2 and the pulleys 3, 4, 5, 6 respectively. ing. Reference numeral 8 denotes an idler pulley provided as appropriate.

  As shown in FIG. 2, the crankshaft 11 is connected to a crank journal 12 rotatably supported by an engine housing (not shown) and a connecting rod (not shown) of a piston, and rotates around the crank journal 12 as an axis. And a crank arm 14 that connects the crank journal 12 and the crank pin 13 to each other. The pulley 2 is attached to one end of the crankshaft 11. In the figure, reference numeral 15 denotes a flywheel attached to the other end of the crankshaft 11.

  As shown in FIG. 3, the pulley 2 attached to one end of the crankshaft 11 includes a viscous coupling 21. The viscous coupling 21 has a hub 22 that is fixed to one end of the crankshaft 11 and a housing 23 that encloses the hub 22. The hub 22 and the housing 23 are relatively rotatable by front and rear bearings 24. A working chamber 26 is formed in a sealed state between the hub 22 and the housing 23.

  The hub 22 is provided with a plurality of inner plates 27 that spline-engage with the outer peripheral surface facing the working chamber 26 and rotate together. The housing 23 is provided with a plurality of outer plates 28 that spline-engage with an inner peripheral surface facing the working chamber 26 and rotate together. The inner plate 27 and the outer plate 28 are alternately overlapped so that the outer plate 28 enters between a pair of adjacent inner plates 27 and the inner plate 27 enters between a pair of adjacent outer plates 28. Are arranged.

  The working chamber 26 is filled with a viscous fluid such as silicon oil. A viscous fluid is interposed between the adjacent inner plate 27 and outer plate 28, and the driving force of the crankshaft 11 is transmitted to the housing 23 by this viscous fluid.

  The outer peripheral surface 23 a of the housing 23 is formed with irregularities that match the cross-sectional shape of the belt 7, and the belt 7 is wound around the outer peripheral surface 23 a of the housing 23. That is, the outer peripheral surface 23 a of the housing 23 is an engagement surface with the belt 7 and thus with the pulleys 3, 4, 5, 6 of each auxiliary machine.

  When torsional vibration occurs in the crankshaft 11, the housing 23 of the viscous coupling 21 rotates in the opposite direction relative to the crankshaft 11 due to its inertia. As a result, the viscous fluid is sheared between the inner plate 27 and the outer plate 28. The energy of vibration of the crankshaft 11 is replaced with the energy of relative rotation of the housing 23 and the thermal energy due to the shearing of the viscous fluid between the inner plate 27 and the outer plate 28, thereby suppressing the torsional vibration of the crankshaft 11. Is done.

  As described above, in the power transmission device 1 of the present embodiment, the viscous fluid is sheared by the plurality of inner plates 27 and the outer plate 28 of the viscous coupling 21 to suppress torsional vibration of the crankshaft 11. Since the contact area with the viscous fluid can be gained by the plurality of plates 27, 28, it is possible to avoid an increase in the size of the individual plates 27, 28, to suppress an increase in weight, and to improve the damping performance. . The viscous coupling 21 and the pulley 2 are integrated with each other with the outer peripheral surface 23 a of the housing 23 of the viscous coupling 21 as an engaging surface of the pulley 2. Thereby, further reduction in size and weight can be achieved.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably. In addition, the material, shape, dimension, numerical value, form, number, arrangement location, and the like of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

  For example, in the above-described embodiments, the rotation transmission elements using the pulleys 2, 3, 4, 5, 6 and the belt 7 have been described. However, the present invention is also applicable to the rotation transmission elements using gears. can do. In that case, gear teeth are formed on the outer peripheral surface of the housing of the viscous coupling. In the above-described embodiment, the pulley 2 attached to the crankshaft 11 that is the rotation shaft of the prime mover has been provided with the viscous cup 21, but the pulleys 3, 4, A viscous coupling may be provided on 5 and 6.

  In the above-described embodiment, the example in which the hub 22 and the housing 23 are relatively rotatable by the front and rear bearings 24 has been described. However, instead of the bearing 24, an annular rubber is used, and the hub 22 and the housing 23 may be directly connected so as to be relatively rotatable within a predetermined range.

It is a figure which shows schematic structure of one Embodiment of the power transmission device of this invention. It is a top view which shows the rotating shaft of a motor | power_engine, and the rotation transmission element attached to this rotating shaft. It is sectional drawing which expands and shows the rotation transmission element of FIG.

Explanation of symbols

1 Power transmission device 2, 3, 4, 5, 6 Pulley (rotational transmission element)
7 Belt 11 Crankshaft (Rotating shaft on the input side)
21 Viscous coupling 22 Hub 23 Housing 23 Outer peripheral surface (engagement surface) of housing
27 Inner plate 28 Outer plate

Claims (3)

A power transmission device including a pair of rotation transmitting elements that are respectively attached to and engaged with an input-side rotating shaft and an output-side rotating shaft, and that transmits a driving force of the input-side rotating shaft to the output-side rotating shaft Because
At least one of the rotation transmission elements includes a viscous coupling;
The viscous coupling includes a hub fixed to the rotating shaft, a housing that includes the hub and is rotatable with respect to the hub, a viscous fluid filled between the hub and the housing, and the viscosity A plurality of inner plates arranged in the fluid and rotating together with the hub, and an outer plate arranged alternately and overlapping with the inner plate in the viscous fluid and rotating together with the housing;
A power transmission device, wherein an outer peripheral surface of the housing of the viscous coupling is an engagement surface with the rotation transmission element on the other side.   The power transmission device according to claim 1, wherein the rotation transmission element is a pulley in which a power transmission belt is wound around an outer peripheral surface and engages with each other via the belt.   The power transmission device according to claim 1, wherein the rotation transmission element is a gear having teeth formed on an outer peripheral surface thereof and meshing with each other.

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