JP2972071B2 - Mechanical supercharger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical supercharger for pressurizing engine intake air.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 2-95731 discloses a mechanical supercharger 201 as shown in FIG. This is because the driving force of the engine is increased by a planetary gear type speed increasing mechanism 203.
And drives the air compressor 205 to pressurize the engine intake air. Speed increasing mechanism 203
Is formed on an impeller shaft 209 of the air compressor 205, and the impeller shaft 209 is supported by a housing 213 via a bearing 211.

[0003]

Since the bearing 211 is a double-row (two-row) ball bearing, there are two support points.
In addition to this, the impeller shaft 209 is
Are centered by a meshing reaction force generated in the sun gear 207 by meshing with the pinion gear 215 disposed around the center gear 215, and are supported at this centering position. With such a three-point support configuration, it is difficult to adjust the three-point alignment. If the centering position is deviated due to the meshing reaction force, a moment load is applied to the bearing 211. Bearing 2
Because 11 does not have the function of allowing vibration and absorbing vibration,
In particular, in a device that rotates at a high speed such as a mechanical supercharger, a large load is applied to the bearing 211 and each gear of the speed increasing mechanism 203 to generate vibration and noise, thereby impairing durability.

Accordingly, an object of the present invention is to provide a mechanical supercharger which is excellent in durability without applying a moment load to the impeller shaft.

[0005]

A mechanical supercharger according to the present invention increases the driving force of an engine via a planetary gear type speed increasing mechanism to drive an impeller shaft of a centrifugal air compressor. A supercharger, wherein the speed increasing mechanism is composed of an internal gear for driving force input, a sun gear for forming the impeller shaft, and three pinion gears meshed with these gears and arranged at substantially equal intervals in a circumferential direction. A floating bush that supports the impeller shaft between the speed increasing mechanism and the impeller is arranged to supply oil to the floating bush, and the impeller shaft meshes with a pinion gear of the speed increasing mechanism. It is characterized in that the support in the radial direction is performed at two points in the axial direction by the reaction force and one floating bush.

[0006]

Since the impeller shaft is supported at two points by the meshing reaction force of the gear of the speed increasing mechanism and one floating bush, it is released from the three-point alignment adjustment, and the support point by the meshing reaction force is set to a predetermined value. Since the floating bush has a function to allow deflection and a function to absorb vibration even if it is slightly deviated from the position, unlike the conventional example, no excessive force is applied to the speed increasing mechanism and the floating bush, and vibration and noise are reduced. It is prevented and the durability is greatly improved.

[0007]

An embodiment will be described with reference to FIGS.
FIG. 1 shows a mechanical supercharger 1 and a pulley 3 of this embodiment. The left and right directions are the left and right directions in FIG. 1, and members without reference numerals are not shown.

As shown in FIG. 1, a mechanical supercharger 1 includes a planetary gear type speed increasing mechanism 5 and a centrifugal air compressor 7.
And

The pulley 3 is fixed to an input shaft 13 of the speed increasing mechanism 5 by a key 9 and a nut 11. The pulley 3 is connected to a pulley on the crankshaft side via a belt,
It is rotationally driven by the driving force of the engine. The input shaft 13 is supported on a housing 17 of the speed increasing mechanism 5 by a bearing 15, and a seal 19 is disposed between the input shaft 13 and the housing 17.

The speed increasing mechanism 5 includes an internal gear 21 formed integrally with the input shaft 13, three pinion gears 23 arranged at regular intervals in the circumferential direction as shown in FIG. 2, and an impeller shaft of the air compressor 7. And a sun gear 27 formed at the second gear 25. The pinion gear 23 is a bearing 2
The pinion shaft 31 is supported by the pinion shaft 31 via the flange 9, and the pinion shaft 31 is supported by the flange member 33 of the housing 17. The speed increasing mechanism 5 rotates the impeller shaft 25 by increasing the driving force of the engine input from the pulley 3 to the internal gear 21. Impeller shaft 25
Is centered by a meshing reaction force received by the sun gear 27 from the three pinion gears 23, and is supported at this centering position.

An impeller 35 is fixed to the right end side of the impeller shaft 25 with a nut 37. A compressor housing 39 of the air compressor 7 is flanged by a connecting member 43 engaged with a circumferential groove 41 of the housing 17 and a bolt 45. Together with the member 33, it is fixed to the housing 17. Thus, the air compressor 7 is configured, and when the impeller 35 is rotationally driven, the air compressor 7 pressurizes the intake air and supplies it to the engine.

The bearing member 4 is provided on the flange member 33.
7 is press-fitted and positioned by the retaining ring 49 and the step 51. A labyrinth seal 53 is fixed to the flange member 33 with a screw 55, and the bearing holder 4
7, a space 57 is formed. In the intake air intake passage of the engine, the downstream side of the throttle valve and the space 57 communicate with each other via the air flow path 59 and the control valve. When the throttle valve closes and a negative pressure is generated on the right side of the impeller 35, the control is performed. The space 57 is opened to the atmosphere by the valve and is always kept at a positive pressure.

A sun gear 27 is provided on the impeller shaft 25.
The rings 61, 63, the spacer 65, and the bush 67 are fitted from the left to the impeller 35 and rotate integrally with the impeller shaft 25. A bush 69 is arranged on the outer periphery of the spacer 65. Oil is supplied to the inner and outer peripheries of the bush 69 to form an oil film as described later, thereby forming a floating bush 71. The center portion of the impeller shaft 25 is supported by the bearing holder 47 via the floating bush 71.

A thrust washer 73 is mounted on the bearing holder 47 from the outside in the radial direction, and is fixed with a bolt 75. The thrust washer 73 is engaged with the groove 77 between the rings 61 and 63, and receives the thrust force of the impeller shaft 25.

Pressurized oil from an oil pump is supplied to the floating bush 71 via an oil passage 79 formed through the bearing holder 47 and the flange member 33, a nozzle 81 and an oil plug 83, thereby forming an oil film. . This oil is also supplied to the groove 77 to lubricate the sliding surface of the thrust washer 73, and further to each gear of the speed increasing mechanism 5 and the bearing 15.

A contact type oil seal 89 formed by a seal 85 and a piston ring 87 is disposed between the bearing holder 47 and the bush 67 to prevent oil from leaking from the housing 17.

Thus, the mechanical supercharger 1 is configured.

The impeller shaft 2 of the air compressor 7
5 is supported at two points by the meshing reaction force of the sun gear 27 and the floating bush 71 as described above, so that unlike the conventional example of three-point support, alignment failure between the support points essentially occurs. No moment load is applied to each support point. In addition, the center position shift and vibration of the sun gear 27 due to the position error or wear of the pinion gear 23 are permitted and absorbed by the vibration allowing function and the vibration absorbing function of the floating bush 71 by the oil film.

In this way, no excessive force is applied to each gear of the speed increasing mechanism 5 and the floating bush 71, and the vibration of the impeller shaft 25 is prevented, so that the mechanical supercharger 1 is quietly rotated and greatly durable. To improve.

[0020]

According to the mechanical supercharger of the present invention, the impeller shaft is connected to the meshing reaction force of the planetary gear type speed increasing mechanism by one.
Since two floating bushes are used to support the two points and the centering position shift and vibration due to the meshing reaction force are absorbed by the floating bush,
These support points are released from the moment load, the rotation is quiet, and the durability is greatly improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mechanical supercharger 5 Planetary gear type speed increasing mechanism 7 Centrifugal air compressor 25 Impeller shaft 71 Floating bush

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tomiaki Ochiai 2388 Omiyacho, Tochigi City, Tochigi Prefecture Tochigi Fuji Sangyo Co., Ltd. (56) References JP-A-57-59928 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F02B 39/04 F02B 39/00

Claims (1)

(57) [Claims] 1. A mechanical supercharger for increasing the driving force of an engine via a planetary gear type speed increasing mechanism and driving an impeller shaft of a centrifugal air compressor, wherein the driving force is applied to the speed increasing mechanism. An input internal gear, a sun gear forming the impeller shaft, and three pinion gears meshing with these gears and arranged at substantially equal intervals in the circumferential direction, and the impeller shaft is formed by a speed increasing mechanism and an impeller. One floating bush to be supported between them is arranged so that oil is supplied to the floating bush, and the impeller shaft is radially supported by the meshing reaction force of the pinion gear of the speed increasing mechanism and one floating bush. The mechanical supercharger is performed at two points in the axial direction.