JP3710254B2 - Turbocharger - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mechanically driven supercharger for supplying air to an internal combustion engine.
[0002]
[Prior art and problems to be solved by the invention]
Conventionally, this type of mechanically driven supercharger is required to rotate at a constant speed within a predetermined range regardless of the engine speed for driving the turbocharger.
For this reason, what transmits the driving torque of an engine to an input shaft via a continuously variable transmission is provided.
[0003]
For example, in Japanese Patent Laid-Open No. 5-280367, the driving force of the internal combustion engine is transmitted to the driving pulley, and is transmitted to the input shaft via the belt via the driven pulley. The runner shaft is driven by the input shaft via the speed increasing gear device, and the runner is driven at high speed rotation via the runner shaft to supercharge the internal combustion engine. However, since such a continuously variable transmission uses a drive pulley and a driven pulley between which a belt is laid, there is a problem that it is large and difficult to apply to an actual machine.
[0004]
In addition, due to tension fluctuations caused by fluctuations in the angular speed of the crankshaft of the engine, the continuously variable transmission and the speed increasing gear device are adversely affected, and the durability of the continuously variable transmission such as belt life and bearing life is reduced. It was. In addition, there is a problem that the bearing life of the speed increasing gear device is reduced and gear noise such as rattling noise is increased.
[0005]
Accordingly, an object of the present invention is to provide a supercharger capable of suppressing a decrease in durability and noise generation due to torque fluctuation.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a supercharger according to a first aspect of the present invention is a turbocharger that drives a runner shaft from an internal combustion engine through a planetary speed increasing mechanism, and the driving torque from the internal combustion engine is transmitted to the planetary speed increasing mechanism. Variable diameter pulleys that transmit to the input shaft, and the variable diameter pulleys are formed on a pair of pulley main bodies that surround the input shaft and on opposite surfaces of the pair of pulley main bodies, respectively. A pair of tapered power transmission surfaces; a power transmission ring sandwiched between the pair of power transmission surfaces so as to be eccentric with respect to the shaft center of the pair of pulleys; and a belt wound around the outer peripheral surface; Urging means for urging the pulley main bodies in a direction approaching each other, the urging means comprising a disc spring that engages with a pair of pulley main bodies at the outer edge portion and the inner edge portion, and the variable diameter pulley is Disc spring It is characterized in that the outer and inner portion further comprises a fulcrum means for supporting a radial center portion of the disc spring so that the phase amount equal displacement in opposite directions.
[0007]
Conventionally, the turbocharger has been increased in size because it uses two pulleys on the driving side and the driven side. However, in the present invention, since one variable diameter pulley is used, the turbocharger can be made smaller. Can do.
Further, a force acts to decenter the power transmission ring due to the belt tension, while a force to return the power transmission ring to the concentric side acts by the biasing means. Therefore, if the belt tension fluctuates, the power transmission ring will be slightly displaced to the eccentric side and the concentric side accordingly, and the contact point between the power transmission ring and the pulley main body will fluctuate in the circumferential direction. Can absorb tension fluctuations. It is possible to suppress the fluctuation of the driving torque from the internal combustion engine side from adversely affecting the planetary speed increasing mechanism and the variable diameter pulley as a continuously variable transmission.
[0009]
In addition , the disc spring that engages each pulley main body at the outer edge and inner edge displaces the outer edge and inner edge by the same amount in opposite directions around the fulcrum, so the axial position of the power transmission ring is constant. Can be maintained. As a result, the belt running center can be maintained constant. As the fulcrum means, a support shaft formed in a disc spring may be inserted, or a spherical bearing may be provided between the support shaft and the through hole.
[0010]
According to a second aspect of the present invention, in the turbocharger according to the first aspect , the outer edge portion and the inner edge portion of the disc spring are engaged with a pair of pulley main bodies so as to be integrally rotatable, and the variable diameter pulley is Further, it is characterized by further comprising connecting means for connecting the disc spring and the input shaft so as to be integrally rotatable via the fulcrum means, including the fulcrum means. In this configuration, the pulley main body and the disc spring rotate integrally, and the coupling means includes the fulcrum means, so that the structure can be simplified.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a sectional view of a supercharger according to an embodiment of the present invention. Referring to FIG. 1, the supercharger 1 includes a variable diameter pulley 2 as a continuously variable transmission driven by an internal combustion engine (not shown), and a planetary speed increasing mechanism 3 driven by the variable diameter pulley 2. The runner 5 in the compressor housing 4 is rotationally driven at high speed through the variable diameter pulley 2 and the planetary speed increasing mechanism 3, and air is pumped through the scroll 6.
[0012]
The planetary speed increasing mechanism 3 includes an input shaft 7 connected to the variable diameter pulley 2 and an output shaft 9 that constitutes a rotating shaft (runner shaft 8) of the runner 5.
The planetary speed increasing mechanism 3 is rotatably supported by a ring gear 10 formed at one end of the input shaft 7, a sun gear 11 formed at one end of the output shaft 9, and a carrier 12 via a rolling bearing 50. A plurality of planetary gears 13 meshing with the sun gear 11 and the ring gear 10 are provided.
[0013]
The carrier 12 has an annular shape fixed to a partition plate 51 between the gear housing 14 and the compressor housing 4 of the planetary speed increasing mechanism 3, and double row angular balls are provided on the inner peripheral surface of the carrier 12. An output shaft 9 is rotatably supported via a rolling bearing 15 made of a bearing. The carrier 12 is fixed to the gear housing 14 so that the planetary gear 13 cannot be revolved for the following reason. That is, if the planetary gear 13 is revolved, the axis of the planetary gear 13 is tilted by bending the support shaft 12a that cantilever-supports the planetary gear 13 by the action of centrifugal force, resulting in gear noise. May increase. In order to prevent this, the carrier 12 is fixed.
[0014]
On the other hand, the input shaft 7 is rotatably supported on an inner peripheral surface of a boss portion 17 that is formed to project from the end surface 16 of the gear housing 14 via a pair of rolling bearings 18. The variable diameter pulley 2 that transmits the drive torque to the input shaft 7 is disposed around the boss portion 17.
The variable diameter pulley 2 includes a connecting member 21 having a hub portion 19 formed of a bottomed cylinder surrounding the boss portion 17 and a disc portion 20 formed at one end of the hub portion 19. The connecting member 21 has a hub portion 19 that is rotatably supported on a peripheral surface of the boss portion 17 via a pair of rolling bearings 22, and a disk portion 20 formed on the end surface 16 of the gear housing 14. A ring-shaped receiving groove 23 is rotatably supported via a rolling bearing 24.
[0015]
Further, the end surface 44 of the hub portion 19 of the connecting member 21 is coupled to the shaft end of the input shaft 7 so as to be integrally rotatable. That is, by fitting a fitting projection 45 having a hexagonal cross section, for example, formed on the shaft end of the input shaft 7 into a fitting hole having the same shape formed on the end surface 44 of the hub portion 19, both Are coupled so as to be integrally rotatable. Reference numeral 46 denotes a nut that is coupled to a threaded portion that protrudes from the end face of the input shaft 7 and fastens the above-described both 7 and 19.
[0016]
Further, the variable diameter pulley 2 is rotatable on the peripheral surface of the hub portion 19 via a sliding bearing 25 and is rotatable on the first pulley main body 26 via a sliding bearing 27. And a second pulley main body 28 supported by the main body. The opposing surfaces of the pair of pulley main bodies 26 and 28 form tapered power transmission surfaces 29 and 30. A power transmission ring 31 having a substantially trapezoidal cross section is sandwiched between the pair of power transmission surfaces 29 and 30 so as to be eccentric with respect to the axis K of the pair of pulley main bodies 26 and 28. A transmission surface 32 to the belt 33 is formed on the outer peripheral surface of the power transmission ring 31, and the belt 33 is wound around the transmission surface 32. The transmission surface 32 is formed with a circumferential groove that meshes with the rib of the belt 33.
[0017]
Reference numeral 43 denotes a stopper fitted in the fitting groove on the outer peripheral surface of the hub portion 19. The stopper 43 prevents the pulley main body 26 from being detached from the hub portion 19 when the power transmission ring 31 is eccentric and the pulley main bodies 26 and 28 move away from each other.
The variable-diameter pulley 2 includes a disc spring 34 as a biasing unit that biases the pair of pulley main bodies 26 and 28 toward each other. Referring to FIG. 2, slits 37 and 38 are formed on the inner edge portion 35 and the outer edge portion 36 of the disc spring 34 at equal circumferences, respectively, while the pulley main bodies 26 and 28 are provided with the slits. Plate-like connection protrusions 39 and 40 which are respectively fitted into the members 37 and 38 are formed radially.
[0018]
Then, the disc spring 34 and the pulley main bodies 26 and 28 rotate together in a state where the connection protrusions 39 and 40 are fitted in the corresponding slits 37 and 38. In addition, a plurality of support holes 41 are formed in the center of the disk spring 34 in the radial direction, and the support holes 41 are fixed to the disk portion 20 of the connecting member 21. A support shaft 42 as a means is passed therethrough. Therefore, the connecting member 21 rotates integrally with the disc spring 34 via the support shaft 42 and transmits torque to the input shaft 7 side. That is, the torque transmitted to the power transmission ring 31 via the belt 33 is transmitted to the input shaft 7 of the planetary speed increasing mechanism 3 via the pulley main bodies 26 and 28, the disc spring 34 and the connecting member 21. It has become.
[0019]
Since the disc spring 34 is supported at the radial center by the support shaft 42 serving as a fulcrum, the inner edge 35 and the outer edge 36 can be displaced in the opposite directions by the same amount (bend in the axial direction). . Therefore, as shown in FIG. 3, when the power transmission ring 36 is eccentric, the axial center position between the pulley main bodies 26 and 28 can always be kept constant. As a result, the position of the width center L of the belt 33 is always maintained. Can be kept constant.
[0020]
In the present embodiment, since two pulleys are not used as in the prior art, the size can be greatly reduced. As a result, there is a problem in space when the supercharger is installed in a vehicle. It will be resolved. Further, when there is a tension variation accompanying the variation of the driving torque from the internal combustion engine side, the power transmission ring 31 is slightly displaced in the eccentric side and the concentric side accordingly, and further, the power transmission ring 31 pulley main body 26, The fluctuations in tension can be absorbed by the 28 contact points changing in the circumferential direction. Therefore, adverse effects on the planetary speed increasing mechanism 3 can be prevented. In other words, it is possible to reduce the adverse effect of tension fluctuations exerted on the planetary speed increasing mechanism 3 by the continuously variable transmission. Further, the life of the rolling bearings 15 and 18 of the planetary speed increasing mechanism 3 can be increased, and the wear of the teeth of the gears 10, 11 and 13 can be suppressed to extend the substantial life. In addition, vibration and noise due to rattling noise can be suppressed.
[0021]
In particular, the disc spring 34 displaces the inner edge portion 35 and the outer edge portion 36 by the same amount in opposite directions with the support shaft 42 as a fulcrum, so that the pulley main bodies 26 and 28 can be brought close by the same stroke amount. The width center L of the belt 33 can be kept constant.
Further, since the pulley main bodies 26 and 28 and the disc spring 34 are integrally rotated and the connecting member 21 includes the support shaft 42 as a fulcrum, the structure of the variable diameter pulley 2 can be simplified. This can contribute to further downsizing of the feeder 1.
[0022]
Next, FIG. 4 shows another embodiment of the present invention. Referring to the figure, this embodiment differs from the embodiment of FIG. 1 in that a planetary gear 47 configured as a two-stage gear is used. The planetary gear 47 is formed by integrally configuring a first gear 48 having a relatively small diameter that meshes with the ring gear 10 and a second gear 49 having a relatively large diameter that meshes with the sun gear 11. The rolling bearing 15 is composed of a pair of single-row angular ball bearings with a spacer interposed therebetween, and a pair of rolling bearings 50 is provided with the spacer interposed therebetween. Since the other configuration is the same as that of the embodiment of FIG.
[0023]
In the present embodiment, in addition to the same effects as the embodiment of FIG. 1, the driven gear driven by the ring gear 10 is the first gear 48 having a small diameter, so that the gear ratio is increased. , Can be increased more speed.
Next, FIG. 5 shows still another embodiment of the present invention. This embodiment is different from the embodiment of FIG. That is,
(1) The pulley main body 26 is supported by the hub portion 19 of the connecting member 21 in the embodiment of FIG. 1, but in this embodiment, the pulley main body 26 is supported by the input shaft 7 via the slide bearing 25. did. The connecting member 21 is directly connected to the input shaft 7 so as to be integrally rotatable. The stopper 43 is attached to the shaft end peripheral surface of the input shaft 7.
(2) Further, in the embodiment of FIG. 1, the support shaft 13a of the planetary gear 13 is cantilevered by the carrier 12, but in this embodiment, the support shaft 13a is supported on both ends. Specifically, the carrier 12 includes an annular first member 52 fixed to a partition plate 51 between the gear housing 14 and the compressor housing 4, a support ring plate 54 of the ring gear 10, and the output shaft 9. The support shaft 13a is supported at both ends by an annular second member 53 interposed therebetween. A rolling bearing 55 is interposed between the second member 53 and the support ring plate 54, and a rolling bearing 56 is interposed between the second member 53 and the output shaft 9. Since the other configuration is the same as that of the embodiment of FIG.
[0024]
In the present embodiment, in addition to the same effects as the embodiment of FIG. 1, the structure of the variable diameter pulley 2 is simplified through the simplification of the structure of the connecting member 21 by the configuration of (1) described above. can do. Further, with the configuration of (2) described above, since the carrier 12 is supported by the support ring plate 54 on the ring gear 10 side and the output shaft 9 on the sun gear 11 side, the meshing accuracy of each gear is improved. Gear vibration and gear noise can be further suppressed.
[0025]
Next, FIG. 6 shows still another embodiment of the present invention. This embodiment is different from the embodiment of FIG. That is,
The carrier 12 includes an annular first member 57 and a second member 58 that support the support shaft 13 a of the planetary gear 13 at both ends. The first member 57 is fixed to the partition ring plate 51, and the inner peripheral surface of the first member 57 supports the output shaft 9 in the radial direction via a fluid lubricated bearing 59 composed of a dynamic pressure spiral groove bearing (SGB). are doing. The second member 58 is supported by the shaft end portion of the output shaft 9 via a fluid lubricated bearing 60 formed of a dynamic pressure spiral groove bearing (SGB) disposed on the inner peripheral surface thereof. The SGB is provided with a helical shallow groove on either the fixed side (carrier 12 side) or the stationary side (output shaft 9 side), and generates fluid pressure by the pumping action of this groove, and the output shaft 9 can be supported in a non-contact manner.
[0026]
In addition, a disc-like rotor 61 is formed at the intermediate portion of the output shaft 9 so as to be integrally rotatable, and between one surface of the rotor 61 and the partition ring plate 51 facing the rotor 61 and the other of the rotor 61. Between these surfaces and the first member 57, fluid lubricated bearings 62 and 63 made of SGB for supporting the output shaft 9 in the axial direction are formed.
The gear housing 14 is filled with lubricating oil, and the lubricating oil scooped up by the gear is transmitted to the surface of the partition ring plate 51 and the carrier 12 to each fluid lubricated bearing 59, 60, 62, 63. The bearing function and the oil film damper function are fulfilled by the generated dynamic pressure.
[0027]
In the present embodiment, in addition to the same effects as the embodiment of FIG. 1, the following advantages are obtained by using the fluid lubricated bearings 59 and 60 made of SGB as described above. In other words, when a rolling bearing is used, when an oil film damper for suppressing vibration of the gear portion is used as in, for example, Japanese Patent Application Laid-Open No. 5-280367, the lubricating oil is forcibly supplied to the rolling bearing. A complicated oil passage configuration was adopted, or a separate pump mechanism was provided. Alternatively, a non-lubricated ceramic bearing is employed, but in this case, it is necessary to lengthen the shaft dimension of the output shaft 9 in all cases. If the shaft dimension is long, it is difficult to increase the natural frequency of the output shaft 9 itself. As a result, resonance occurs in the normal range, causing vibration and noise, and durability is also lowered. Further, in the rolling bearing, preload loss occurs due to the axial force received by the output shaft 9 due to the rotation of the runner 5, which may cause damage to the rolling bearing.
[0028]
On the other hand, when the fluid lubricated bearings 59, 60, 62, and 63 made of SGB are used as in the present embodiment, the bearing itself contributes to the oil supply to itself and fulfills the function of the oil film damper. Thereby, gear vibration and gear noise can be suppressed. In particular, the gear vibration can be effectively suppressed by disposing the meshing portions of the gears 10, 11, and 13 between the fluid lubricated bearings 59, 60.
[0029]
In addition, since the size of the output shaft 9 is not increased, the turbocharger 1 can be reduced in size, and vibrations and noises that are substantially problematic can be suppressed by increasing the natural frequency. it can.
In addition, the conventional oil film damper system requires an oil passage configuration and a pump for forcibly supplying oil. However, in this embodiment, such a configuration is not necessary, so the structure of the supercharger is further simplified. Therefore, it is possible to realize a supercharger that is small in size, low in manufacturing cost, and low in vibration and noise.
[0030]
The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention.
[0031]
【The invention's effect】
According to the first aspect of the present invention, since two pulleys are not used as in the prior art, the size can be reduced. In addition, when there is a tension fluctuation due to the fluctuation of the driving torque from the internal combustion engine side, the power transmission ring is slightly displaced to the eccentric side and the concentric side accordingly, and the contact point between the power transmission ring and the pulley main body The tension variation can be absorbed by the variation in the circumferential direction. Therefore, it is possible to improve the durability of the planetary speed increasing mechanism and the variable diameter pulley as a continuously variable transmission, and to suppress vibration and noise. Further, since the disc spring displaces the outer edge portion and the inner edge portion in the opposite directions by the same amount with the fulcrum as the center, the pulley main body can be moved closer and closer by the same stroke amount, so that the belt running center is kept constant. be able to.
[0032]
In the invention 請 Motomeko 2, wherein rotating the pulley main and disc spring integrally, the coupling means is configured to include a fulcrum means, the structure of the variable diameter pulley can be simplified, the thus turbocharger This can contribute to downsizing.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a supercharger as an embodiment of the present invention.
FIG. 2 is a front view of a disc spring.
FIG. 3 is a schematic cross-sectional view of a variable diameter pulley showing a state where a power transmission ring is eccentric.
FIG. 4 is a cross-sectional view of a supercharger according to another embodiment of the present invention.
FIG. 5 is a cross-sectional view of a supercharger according to still another embodiment of the present invention.
FIG. 6 is a cross-sectional view of a supercharger according to still another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Supercharger 2 Variable diameter pulley 3 Planetary speed increasing mechanism 7 Input shaft 8 Runner shaft 9 Output shaft 10 Ring gear 11 Sun gear 12 Carrier 13 Planetary gear 21 Connecting member 26 First pulley main body 28 Second pulley main body 29, 30 Power transmission Surface 31 Power transmission ring 33 Belt 34 Belleville spring 35 Inner edge 36 Outer edge 37, 38 Slit 39, 40 Connecting protrusion 41 Support hole 42 Support shaft (fulcrum means)
45 Fitting protrusion L Belt width center

Claims (2)

In a supercharger that drives a runner shaft from an internal combustion engine through a planetary speed increasing mechanism,
A variable diameter pulley that transmits drive torque from the internal combustion engine to the input shaft of the planetary speed increasing mechanism;
This variable diameter pulley
A pair of pulley main bodies provided around the input shaft;
A pair of tapered power transmission surfaces respectively formed on opposing surfaces of the pair of pulley main bodies,
A power transmission ring sandwiched between the pair of power transmission surfaces so as to be eccentric with respect to the shaft center of the pair of pulleys, and a belt is wound around the outer peripheral surface;
Urging means for urging the pair of pulley main bodies toward each other ,
The biasing means comprises a disc spring that engages with a pair of pulley main bodies at the outer edge portion and the inner edge portion, respectively.
The variable diameter pulley further includes a fulcrum means for supporting a central portion in the radial direction of the disc spring so that an outer edge portion and an inner edge portion of the disc spring are opposite to each other and are displaced by an equal amount . The outer edge and inner edge of the disc spring are engaged with a pair of pulley main bodies so as to be integrally rotatable,
2. The supercharger according to claim 1 , wherein the variable diameter pulley further includes connecting means including the fulcrum means and connecting the disc spring and the input shaft via the fulcrum means so as to be integrally rotatable .

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