JPH0742797A - Vibrationproof structure of planetary gear - Google Patents

Abstract

PURPOSE:To promote a reduction in noises in forestalling the propagation of meshing vibration by supporting a gearbox with a built-up planetary gear mechanism elastically with a concentric boss part with both input-output shafts, while backing up it with each hydraulic cylinder set up right and left from the shaft center. CONSTITUTION:Rotation of a drive shaft 1 in a driving device is transmitted to an output shaft from an input shaft 2 via a sun gear 8, a planetary gear 9 and an internal gear 10 and finally to a propeller shaft 3. Here dead load of a gearbox 6 is supported by a support block 19 and a thrust bearing block 12 via two support pieces 20 and 23, and in this case, if each spring constant of these support pieces 20 and 23 is selected so as to become a specified relationship to each dead load of a planetary gear mechanism 5 and the gearbox 6 and a meshing vibration frequency of this planetary gear mechanism 5, a meshing vibration is absorbed by the support pieces 20 and 23. In addition, the moment of rotation acting on the gearbox 6 due to meshing reaction of the planetary gear mechanism 5 is absorbed by two hydraulic cylinders 24 and 25 constituting a hydraulic closed circuit, whereby a solid-propagation vibration to be transmitted to a ship hull from an installation base 11 is sharply reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolation structure for a planetary gear device.

[0002]

2. Description of the Related Art Generally, in a ship, the rotation of a drive shaft of a drive unit such as a diesel engine is transmitted to a propeller shaft via a planetary gear unit. One example thereof is shown in FIG. Such as, 1 is the drive shaft of the drive device, 2 is the input shaft connected to the drive shaft 1,
3 is a propeller shaft, 4 is an output shaft connected to the propeller shaft 3, 5 is a planetary gear mechanism for transmitting the rotation of the input shaft 2 to the output shaft 4, 6 is a gear box of the planetary gear mechanism 5, and 7 is a propeller shaft. 3 is a thrust bearing for receiving a propeller thrust transmitted from the drive shaft 3 to the output shaft 4, and the rotation of the drive shaft 1 of the drive device is such that the input shaft 2 rotates the sun gear 8 integral with the input shaft 2, the planetary gear 9, and the output. The rotation of the output shaft 4 is transmitted to the propeller shaft 3 by being transmitted to the output shaft 4 via the shaft 4 and an internal gear 10 connected by a gear joint.

[0003]

However, in the planetary gear device as described above, the thrust bearing 7 that receives the propeller thrust is integrally incorporated in the gear box 6 of the planetary gear mechanism 5, and the gear box 6 is Since a large thrust of the propeller and a rotational moment due to the meshing reaction force of the planetary gear mechanism 5 are received, the gear box 6 is fixed to the mounting base 11 fixed to the hull by a large number of reamer bolts and tightening bolts (not shown). It has to be firmly fixed, which results in
The meshing vibration generated at the meshing portion of the gears 8, 9 and 10 of the planetary gear mechanism 5 is transmitted from the gears 8, 9 and 10, the bearing, the gear box 6 and the fixing bolts to the hull as solid propagating vibration, and the wall of the cabin etc. Radiated from it, causing noise problems.

For this reason, measures have been taken to improve the accuracy of the gears, modify the tooth profile, etc. to reduce the occurrence of meshing vibration itself, but there is a limit in terms of machining accuracy and cost.

On the other hand, as shown in FIG. 4, the thrust bearing block 12 having a built-in thrust bearing and the gear box 6 having a planetary gear mechanism are independent of each other, and the gear box 6 is supported by an elastic member 13, and Thrust bearing block 1
The gearbox 6 is vibration-proofed by interposing a misalignment absorbing joint 14 between the gearbox 6 and the gearbox 6, and a high misalignment absorbing elastic joint 16 between the gearbox 6 and the drive unit 15, respectively. It is possible, but in this case,
Since the thrust bearing block 12 and the gear box 6 are separately installed, the installation space becomes large, and the large rotation moment acting on the gear box 6 also causes a large space for vibration-proof support. Becomes Further, since the change in alignment is large, a very expensive joint such as the misalignment absorption joint 14 or the high misalignment absorption type elastic joint 16 is required, which is not practical.

In view of the above-mentioned circumstances, the present invention provides the installation base side of the meshing vibration generated at the meshing portion of the gears of the planetary gear mechanism without increasing the installation space and without using an expensive joint or the like. It is an object of the present invention to provide a vibration isolation structure for a planetary gear device that can prevent propagation and suppress noise generation.

[0007]

According to the present invention, an input shaft connected to a drive shaft of a drive unit, an output shaft connected to a propeller shaft, and a planetary gear for transmitting the rotation of the input shaft to the output shaft. A vibration-proof structure for a planetary gear device including a mechanism,
A thrust bearing block containing a thrust bearing for receiving a thrust force from a propeller shaft acting on the output shaft is fixed on a mounting table, and the input shaft is provided on the input shaft side of a gear box containing the planetary gear mechanism. A boss portion that is concentrically provided with the boss is rotatably supported by a support base fixed on the installation base via a support piece having a desired spring constant, and the output is provided on the output shaft side of the gear box. A boss portion projecting concentrically with the shaft is rotatably supported on the thrust bearing block via a support piece having a desired spring constant, and a 180 ° phase shift about the shaft center of the gear box. The hydraulic cylinders arranged side by side on the installation base are connected to the positions displaced from each other, and the rod side chamber and the head side chamber of the one hydraulic cylinder are connected to the head side chamber and the rod side chamber of the other hydraulic cylinder, Previous It is characterized in that to constitute a closed hydraulic circuit for supporting the rotating moment acting on the gearbox by meshing reaction force of the planetary gear mechanism.

[0008]

Therefore, the rotation of the drive shaft of the drive device is transmitted from the input shaft to the output shaft via the planetary gear mechanism, and the rotation of the output shaft is transmitted to the propeller shaft.

Here, the self-weight of the gear box is supported by the support base and the thrust bearing block via the support piece, and the vibration is determined by the spring constant k of the support piece and the self-weight of the planetary gear mechanism and the gear box. The eigenvalue f _{0 of the} system is f / f _{0 with} respect to the meshing frequency f generated at the meshing portion of the planetary gear mechanism.
If the spring constant k of the support piece is selected so that> 2.5, the meshing vibration generated at the meshing part of the planetary gear mechanism is isolated by the support piece and propagated to the mounting table. Is significantly reduced and is not emitted as noise.

Further, the rotational moment acting on the gear box by the meshing reaction force of the planetary gear mechanism is supported by a hydraulic cylinder forming a hydraulic closed circuit, and the spring constant kc of the hydraulic closed circuit and the gear box (depending on the case). Is an eigenvalue of torsional vibration F _{0, which} is determined by the polar moment of inertia of the shaft after the gear box and the propeller) and f / F with respect to the meshing frequency f during the rotation moment due to the meshing reaction force of the planetary gear mechanism.
So that ₀ > 2.5, the spring constant kc of the hydraulic closed circuit
Is selected, and based on the spring constant kc, the sectional area of each hydraulic cylinder, the total volume V of the rod side chamber, the head side chamber, and the oil passage V
, The meshing vibration during the rotation moment due to the meshing reaction force of the planetary gear mechanism is isolated by the hydraulic cylinders that make up the hydraulic closed circuit, and the solid propagation vibrations transmitted to the installation base are significantly reduced, resulting in noise. It will not be emitted.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an embodiment of the present invention. In the drawings, the parts designated by the same reference numerals as those in FIG. 3 represent the same parts, and from the propeller shaft 3 acting on the output shaft 4. A thrust bearing block 12 having a built-in thrust bearing 7 for receiving the thrust force is fixed on a mounting base 11 by a plurality of bolts 17, and a gear box 6 having a planetary gear mechanism 5 built therein.
Of the boss 1 projecting concentrically with the input shaft 2 on the input shaft 2 side of the
8 is rotatably supported on a support base 19 fixed on a mounting base 11 via a support piece 20 having a desired spring constant k, and the output shaft 4 is provided on the output shaft 4 side of the gear box 6. A boss portion 21 that is provided concentrically with is rotatably supported by the boss portion 22 of the thrust bearing block 12 via a support piece 23 having a desired spring constant k.
As the support pieces 20 and 23, for example, a metal such as rubber, synthetic resin, or aluminum having a small elastic coefficient is used, and the spring constant k of the support pieces 20 and 23 and the planetary gear mechanism 5 and the gear box 6 are set. Eigenvalue f of the vibration system determined by its own weight
₀ is the meshing frequency f generated at the meshing portion of the planetary gear mechanism 5.
On the other hand, the spring constant k of the support pieces 20 and 23 is selected so that f / f ₀ > 2.5.

Further, with the axis O of the gear box 6 as the center,
Hydraulic cylinders 24 and 25 arranged side by side on the installation base 11 are connected at positions shifted by 80 ° in phase, and the rod side chamber 24a of the one hydraulic cylinder 24 and the head side chamber 25b of the other hydraulic cylinder 25 are oiled. The head side chamber 24b of the one hydraulic cylinder 24 and the rod side chamber 25a of the other hydraulic cylinder 25 are connected to each other via the passage 26.
A hydraulic closed circuit 28 for supporting a rotational moment acting on the gear box 6 by the meshing reaction force of the planetary gear mechanism 5 is formed.

The spring constant kc of the hydraulic closed circuit 28 is K, the bulk elastic coefficient of oil, S is the cross-sectional area of each hydraulic cylinder 24, 25, the rod side chamber 24a, the head side chamber 25b, and the oil passage 2.
If the total volume of 6 is V,

Since it is given by kc = K · S ² / V, the spring constant kc of the hydraulic closed circuit 28 and the polar inertia of the gear box 6 (including the shaft and the propeller after the gear box 6 in some cases) The torsional vibration eigenvalue F ₀ determined by the moment and the meshing frequency f in the rotation moment due to the meshing reaction force of the planetary gear mechanism 5 is f / F ₀ > 2.
5, the spring constant kc of the hydraulic closed circuit 28 is selected, and based on the spring constant kc, the sectional area S of the hydraulic cylinders 24 and 25, the rod side chamber 24a, the head side chamber 25b, and the oil passage 26 are selected. Determine the total volume V.

Incidentally, 29 is a limit switch for detecting the rotational displacement of the gear box 6, and 30 and 31 are limit switches 29.
The hydraulic cylinder 2 is opened and closed based on the detection signal from the
It is a valve for supplying / discharging the oil for the leak at 4 and 25.

Next, the operation of the above embodiment will be described.

The rotation of the drive shaft 1 of the drive device is transmitted from the input shaft 2 to the output shaft 4 via the sun gear 8 integral with the input shaft 2, the planetary gear 9, and the internal gear 10. Output shaft 4
Is transmitted to the propeller shaft 3.

Here, the weight of the gear box 6 is supported by the support base 19 and the thrust bearing block 12 via the support pieces 20, 23, and the support pieces 20, 23 are supported.
The eigenvalue f _{0 of the} vibration system, which is determined by the spring constant k and the weight of the planetary gear mechanism 5 and the gear box 6, is f / f ₀ > 2.5 with respect to the meshing frequency f generated at the meshing portion of the planetary gear mechanism 5. If the spring constant k of the supporting pieces 20 and 23 is selected so that, the meshing vibration generated at the meshing portion of the planetary gear mechanism 5 is isolated by the supporting pieces 20 and 23, and the mounting base 11 Solid-borne vibration transmitted to the hull is significantly reduced, and it is not radiated as noise from walls such as the cabin.

The rotational moment acting on the gear box 6 by the meshing reaction force of the planetary gear mechanism 5 is the hydraulic closed circuit 2.
8 is supported by the hydraulic cylinders 24 and 25, and the torsional vibration characteristic _value F ₀ determined by the spring constant kc of the hydraulic closed circuit 28 and the polar moment of inertia of the gear box 6 is the meshing reaction force of the planetary gear mechanism 5. The spring constant kc of the hydraulic closed circuit 28 is selected so that f / F ₀ > 2.5 with respect to the meshing frequency f in the rotation moment due to the hydraulic cylinders 24, If the cross-sectional area S of 25 and the total volume V of the rod-side chamber 24a, the head-side chamber 25b, and the oil passage 26 are determined, the meshing vibration during the rotation moment due to the meshing reaction force of the planetary gear mechanism 5 causes the hydraulic closed circuit 28 to move. The solid-state propagating vibration transmitted from the installation base 11 to the hull is significantly reduced by the constituent hydraulic cylinders 24 and 25, and is not radiated as noise from the wall of the cabin or the like.

On the other hand, the rod side chamber 24 of the hydraulic cylinder 24
When the gear box 6 is rotationally displaced due to an oil leak from a to the head side chamber 24b and an oil leak from the head side chamber 25b of the hydraulic cylinder 25 to the rod side chamber 25a, the rotational displacement of the gear box 6 is limited by a limit switch. 29, and based on the detection signal from the limit switch 29, the valve 30 is opened to inject the leak oil from the B port, and the valve 31 is opened to remove the leak oil from the A port. As a result, the gear box 6 is held horizontally.

In this way, it is possible to prevent the meshing vibration generated at the meshing portion of the planetary gear mechanism 5 from propagating to the mounting base 11 side without increasing the installation space and without using an expensive joint or the like, and to reduce noise. Occurrence can be suppressed.

The anti-vibration structure of the planetary gear device of the present invention is as follows.
The present invention is not limited to the above embodiment, and the planet gear 9 does not revolve around the sun gear 8 as shown in FIG.
Instead of the so-called star type planetary gear device, the planetary gear 9 revolves around the sun gear 8, may be applied to a so-called planetary type planetary gear device, and the like, within the scope of the present invention. It goes without saying that various changes can be made in.

[0023]

As described above, according to the vibration isolating structure of the planetary gear device of the present invention, the meshing of the gears of the planetary gear mechanism is achieved without increasing the installation space and without using an expensive joint or the like. It is possible to prevent the transmission of the meshing vibration generated in the section to the side of the mounting base and to suppress the generation of noise, which is an excellent effect.

[Brief description of drawings]

FIG. 1 is a plan sectional view of an embodiment of the present invention.

FIG. 2 is a schematic front view schematically showing how to support a gear box with respect to a rotation moment in an embodiment of the present invention.

FIG. 3 is a schematic side cross-sectional view showing an example of a conventional vibration damping structure for a planetary gear device in which a thrust bearing block is integrated.

FIG. 4 is a schematic side view showing an example of a conventional vibration damping structure for a planetary gear device in which a thrust bearing block is provided separately.

[Explanation of symbols]

 1 Drive shaft 2 Input shaft 3 Propeller shaft 4 Output shaft 5 Planetary gear mechanism 6 Gear box 7 Thrust bearing 11 Installation base 12 Thrust bearing block 19 Support base 20 Support piece 21 Boss section 22 Boss section 23 Support piece 24 Hydraulic cylinder 24a Rod side chamber 24b Head side chamber 25 Hydraulic cylinder 25a Rod side chamber 25b Head side chamber 28 Hydraulic closed circuit

Claims (1)

[Claims] 1. A planetary gear device including an input shaft connected to a drive shaft of a drive device, an output shaft connected to a propeller shaft, and a planetary gear mechanism for transmitting the rotation of the input shaft to the output shaft. A vibration-proof structure, wherein a thrust bearing block having a built-in thrust bearing for receiving a thrust force from a propeller shaft acting on the output shaft is fixed on a mounting table, and a gear box having the planetary gear mechanism built-in A boss portion projecting concentrically with the input shaft on the side of the input shaft is rotatably supported by a support base fixed on a mounting base via a support piece having a desired spring constant, and the gear A boss portion, which is provided concentrically with the output shaft on the output shaft side of the box, is rotatably supported by the thrust bearing block via a support piece having a desired spring constant. 180 ° around the axis Connect the hydraulic cylinders arranged side by side on the installation base at the positions out of phase, and connect the rod side chamber and the head side chamber of the one hydraulic cylinder to the head side chamber and the rod side chamber of the other hydraulic cylinder. A vibration isolation structure for a planetary gear device, comprising a hydraulic closed circuit for supporting a rotational moment acting on a gear box by a meshing reaction force of the planetary gear mechanism.