JPH05280536A - Oil film damper - Google Patents

Abstract

PURPOSE:To provide an oil film damper wherein balancing a rotary side member, preventing a damper effect from its decrease due to a temperature change and providing smallness in a diameter of a bearing can be attained while forming an oil film between a collar supported by a fixed side member and the bearing. CONSTITUTION:An oil film damper 1 comprises a shaft 49 fixed with a rotary unit 51, bearing 57 for supporting this bearing 49 and a collar 55 supported by a fixed side member 113 to support the bearing 57 through an oil film 59 and also having a stopper part 63 for restricting moving of the bearing 57 to a side of the rotary unit 51. Further, this stopper part 63 is formed into a separate unit from the other part 61 of the collar 55.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil film damper.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 3-500317 discloses a "mechanical drive type supercharger for an internal combustion engine". As shown in FIG. 3, this is a supercharger 203 via a speed increasing mechanism 201.
Is a mechanical supercharger that is driven by an engine. Impeller 2
The shaft 207 to which 05 is fixed is a guide sleeve 209.
Is supported by bearings 211 and 211 mounted on the inner circumference of the housing 213 of the speed increasing mechanism 201 (fixed side member)
Between the guide sleeve 209 and the guide sleeve 209, an oil film damper 215 for supporting these rotating side members with an oil film.
Are formed.

[0003]

By the way, in the structure as described above, the housing 213, which is generally a stationary member, is used.
Is made of a light alloy such as aluminum for weight reduction, and the guide sleeve 209 and the bearings 211, 211 are made of steel for strength and wear resistance. Therefore, the thickness of the oil film changes due to the difference in thermal expansion coefficient between the two, and the damper action becomes unstable. Further, since the oil film is formed between the housing 213 and the guide sleeve 209, the impeller 205, the shaft 207, the guide sleeve 2
09, bearings 211 and 211 have a heavy weight on the rotating side, and a uniform oil film cannot be formed over the entire circumference, and a normal damper effect cannot be obtained.

Further, the above-mentioned rotary member is assembled in the housing 203 after balancing the rotation, and the member 21
Since the position is fixed by 7 and the bolt 219, the rotational balance is disturbed and the damper action becomes unstable.

Therefore, according to the present invention, the oil film is formed between the collar and the bearing supported by the stationary member, the rotating member is balanced, the damper effect is prevented from lowering due to temperature change, and the bearing has a small diameter. The purpose of the present invention is to provide an oil film damper that can be used in various applications.

[0006]

An oil film damper of the present invention supports a shaft to which a rotating body is fixed, a bearing that supports the shaft, and a bearing that is supported by a fixed member and that supports the bearing through an oil film. A collar having a stopper portion for restricting the movement of the bearing toward the rotating body is also provided, and the stopper portion is separate from other portions of the collar.

[0007]

The outer circumference of the bearing can be chucked by removing the other portion of the collar which is separate from the stopper portion, and balancing can be achieved. Assembling is done by attaching the other part of the collar to the fixed side member, and then, while assembling a small assembly consisting of the rotating body, the shaft, the bearing and the stopper part to the fixed side member, the stopper part of the collar and the other part. Assemble.

If the collar and the bearing are made of the same type of material, the damper effect is prevented from being lowered due to a large difference in thermal expansion coefficient, the rotating side member can be smoothly rotated, and abnormal vibration is prevented from occurring. Since the difference in thermal expansion coefficient is released, a light alloy is used for the stationary member, and the device can be kept lightweight. In addition, the diameter of the bearing is reduced due to the arrangement of the collar, so that the rotating member is lightened, and the damper effect is further improved.

Since the stopper portion of the collar is provided separately to enable balancing, it is possible to easily obtain the above-mentioned effects by disposing the collar.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described with reference to FIGS.
As shown in FIG. 1, the oil film damper 1 of this embodiment is used in a centrifugal air compressor type supercharger 3. Hereinafter, the left and right directions are the left and right directions in FIG. 1, and members and the like without reference numerals are not shown.

FIG. 1 shows an oil film damper 1, a supercharger 3, a speed increasing mechanism 5, and a driven pulley 7 of a belt type continuously variable transmission.

This belt type continuously variable transmission includes a driven pulley 7, a drive pulley, and a belt 9 connecting them, and the drive pulley is rotationally driven by the crankshaft of the engine via a belt transmission mechanism.

The driven pulleys 7 are respectively speed-up mechanisms 5.
The hollow shaft 15 and the cam member 17, which are press-fitted to the input shaft 11 and prevented from falling off by the nut 13, the fixed flange 19 integral with the hollow shaft 15, and the cam member 17 axially moved via the meshing portion 21. And a movable flange 23 that is freely connected. The belt 9 is mounted between the flanges 19 and 23. The right end of the hollow shaft 15 is supported by the casing 25 of the speed increasing mechanism 5 via a bearing 27, and the input shaft 11 is supported by the casing 25 via bearings 29 and 31.
Is supported by.

Cam surfaces 33, 33 are formed on the cam member 17 and the movable flange 23, respectively, and a fly weight 35 is arranged between them. When the driven pulley 7 rotates, the centrifugal force of the fly weight 35 causes the cam surface 33,
33, a cam thrust force is generated, and the movable flange 23
Is pressed to the fixed flange 19 side. On the other hand, the drive pulley is equipped with a spring that presses its movable flange toward the fixed flange side to narrow the flange spacing and give tension to the belt 9, and the cam thrust force increases as the engine speed increases. When it becomes larger, the flange spacing of the driven pulley 7 becomes narrower, the pulley pitch diameter R becomes larger, and the speed increasing rate of the belt type continuously variable transmission decreases. Further, when the engine speed decreases and the cam thrust force decreases, the pulley pitch diameter R decreases due to the belt tension and the speedup rate increases. In this way, the fluctuation range of the rotational speed on the driven pulley 7 side is suppressed to be smaller than the fluctuation range of the engine rotational speed, and the rotational speed of the driven pulley 7 is kept substantially constant as the engine rotational speed increases.

The speed increasing mechanism 5 is of a planetary gear mechanism type, an internal gear 37 is integrally formed on the right end side of the input shaft 11, and a pinion gear 39 is supported on a pinion shaft 41 via a bearing 40. There is. The pinion shaft 41 is a flange portion 43 of the casing 25.
It is supported by the (fixed member), and is provided with a drop-out preventing means 45 including a screw and a ball. The flange portion 43 is made of an aluminum alloy, and the flange portion 43 and the casing 2
A 0 ring 46 is arranged between the five. Sun gear 4
7 is formed at the left end of the shaft 49 (axis) of the supercharger 3.

An impeller 51 is provided at the right end of the shaft 49.
(Rotating body) is press-fitted, and the fall prevention member 53 is caulked. A steel collar 55 is attached to the flange portion 43, and the shaft 49 is a unit bearing 57.
It is supported by the collar 55 via the (bearing) and the oil film 59. The collar 55 is the cylindrical portion 61 on the left side.
(Other part) and right side stopper part 6 press-fitted into this
It has a two-part configuration with three. The oil film 59 is formed between the cylindrical portion 61 and the unit bearing 57, and supports the rotating member 65 including the unit bearing 57, the shaft 49, and the impeller 51 in a floating state. The stopper portion 63 works together with the unit bearing 57 to regulate the rightward movement of the rotary member 65. or,
The collar 55 is axially positioned by a retaining ring 67 mounted on the cylindrical portion 61 and a stopper portion 69 between the stopper portion 63 and the flange portion 43.

Thus, the oil film damper 1 is constructed.

Seals 71, 73 and 74 are arranged between the input shaft 11 and the casing 25 and between the stopper portion 63 of the collar 55 and the shaft 49 and the flange portion 43, respectively. The cylindrical portion 61 of the collar 55 is preliminarily attached to the flange portion 43, and the rotary side member 65 is chucked on the outer periphery of the unit bearing 57 in a state where the seal 73 and the stopper portion 63 are mounted, and then rightward. Is assembled to the flange portion 43, and the stopper portion 63 is pressed into the cylindrical portion 61 at this time. In this way, by making the stopper portion 63 of the collar 55 a separate body, the unit bearing 57 can be chucked and balanced.

An oil plug 75 connected to an oil pump is attached to the upper portion of the casing 25, and the oil is supplied to the oil film 59 through the nozzle 77, the flange portion 43 and the oil passages 79 and 81 provided in the cylindrical portion 61. It is supplied and is supplied to the unit bearing 57 via the oil passage 83. This oil is supplied from the right end side of the oil film 59 to the oil passage 8 provided in the stopper portion 63 as shown in FIG.
5 is supplied to the seal 73 through the oil film 59.
From the left end side of the internal gear 37 via the speed increasing mechanism 5.
Is supplied to the bearings 29, 31 from the through hole 87 of
The oil is discharged from the oil sump 89 below the casing 25 to the outside through the discharge port.

The compressor housing 91 of the supercharger 3 is fixed to the casing 25 via a connecting member 95 engaged with a circumferential groove 93 provided in the casing 25 and a bolt 97. The driving force of the engine input to the input shaft 11 through the belt type continuously variable transmission is increased in speed through the internal gear 37, the pinion gear 39 and the sun gear 77 to rotationally drive the supercharger 3. The supercharger 3 pressurizes the intake air and supercharges the engine. The rightward force applied to the impeller 51 due to the negative pressure generated in the suction port 99 of the compressor housing 91 due to the rotation of the impeller 51 is restricted by the stopper portion 63 of the collar 55 as described above. The clearance S with 91 is properly maintained, and the performance of the supercharger 3 is stabilized.

Since the collar 55 is made of steel, there is no difference in the coefficient of thermal expansion from the unit bearing 57 made of steel,
The film thickness of the oil film 59 does not fluctuate due to the temperature rise when the supercharger 3 is activated or the change of the outside air temperature. In addition to this, the use of the collar 55 reduces the diameter of the unit bearing 57, which reduces the weight of the rotary member 65. For these reasons, the oil film damper 1 always has a large damper effect, and abnormal vibration does not occur.

Further, by using the collar 55, the difference in thermal expansion coefficient is released, and the flange portion 43 is made of aluminum, so that the entire apparatus can be kept lightweight. Color 55
By dividing the structure, the balance can be achieved and the color can be used, and various effects associated with the use of the color as described above can be obtained.

[0023]

The oil film damper of the present invention forms an oil film between the collar attached to the fixed member and the bearing, and the stopper portion of the collar provided on the side of the rotating body on the shaft supported by the bearing. By separating the collar from other parts, it is possible to balance the rotating side member, prevent the deterioration of the damper effect due to the difference in coefficient of thermal expansion, reduce the diameter of the bearing, and reduce the weight of the device. Accompanying effects can be obtained. Also, the assembly after balancing is easy, the balance after assembly is normally maintained, and the oil film can be formed uniformly over the entire circumference.

[Brief description of drawings]

FIG. 1 is a sectional view showing an 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] 1 Oil film damper 43 Flange part (fixed member) 49 Shaft (shaft) 51 Impeller (rotating body) 55 Color 57 Unit bearing (bearing) 59 Oil film 61 Cylindrical part (other part) 63 Stopper part

Claims (1)

[Claims] 1. A shaft to which a rotating body is fixed, a bearing that supports the shaft, a stopper that is supported by a fixed side member, supports the bearing through an oil film, and restricts movement of the bearing toward the rotating body. An oil film damper comprising: a collar having a portion, and the stopper portion being a separate body from other portions of the collar.