JPS5939618B2 - gear transmission - Google Patents

Description

[Detailed description of the invention] The present invention relates to a gear transmission.

More specifically, the present invention relates to a gear transmission equipped with a hydrostatic bearing having a control function as a thrust bearing.

When a gear transmission is directly connected to a prime mover such as a diesel engine, the torque of the prime mover fluctuates significantly, and torsional vibration resonance occurs at a rotation speed determined by the overall vibration system, causing damage to the transmission and transmission shaft. It may get damaged.

To prevent such accidents, an expensive elastic joint is generally provided between the prime mover and the transmission to dampen the torsional vibrations.

However, when the prime mover becomes a horse-powered engine, such as one used for ships, elastic joints must be made of rubber or leaf springs, which not only is difficult to manufacture, but also shortens its lifespan and becomes extremely expensive. The problem is that it has no choice but to do so.

The purpose of the present invention is to accurately prevent resonance of torsional vibrations and smooth out fluctuating torque at the same time without installing expensive elastic joints even if the prime mover is a horse-powered engine.

It is an object of the present invention to provide a gear transmission device which can perform the above-mentioned precise adjustment immediately when switching between forward and reverse rotation.

A gear transmission according to the present invention that achieves the above object transmits power from a drive shaft to a driven shaft via a gear train of helical gears, and at least one of the drive shaft and the driven shaft is configured to be driven in forward and reverse directions. In a gear transmission equipped with two hydrostatic bearings that alternately switch to the load side and anti-load side of the thrust, the discharge amount is controlled by the hydraulic pressure detection of the load side hydrostatic bearing in both the hydrostatic bearings. This hydraulic pump is characterized in that the hydraulic pumps are connected via switching valves so that the flow paths can be switched alternately, and that a high restriction is provided in the flow path connected to the anti-load side hydrostatic bearing.

That is, the present invention provides a gear transmission in which at least one of the drive shaft and the driven shaft is provided with two static pressure bearings that alternately switch between the load side and the anti-load side of thrust according to forward and reverse drive. By controlling the hydraulic pressure supplied to the pressure bearing according to the hydraulic pressure of the load-side hydrostatic bearing, the hydraulic pressure that optimizes the damping effect on the hydrostatic bearing and the smoothing of fluctuating torque can be generated in response to any torque fluctuation. The vibration damping effect is maximized, and when the drive direction is switched between forward and reverse, the static pressure bearing, which was previously on the anti-load side, immediately acts on the load side to ensure normal operation. This is to make it possible to do so.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below with reference to embodiments shown in the drawings.

FIG. 1 shows the main parts of a gear transmission according to the present invention.

In FIG. 1, 1 is a driving gear fixed to a drive shaft 3, and 2 is a driven gear fixed to a driven shaft 4.

The driving gear 1 and the driven gear 2 each consist of a helical gear and mesh with each other, so that the power from a prime mover 5 such as a diesel engine is input to the drive shaft 3, and is transmitted to the driven shaft 4 at a variable speed. ing.

The connection between the prime mover 5 and the drive shaft 3 is performed by a coupling such as a gear coupling, for example, so that the drive shaft 3 can move slightly in the axial direction.

The drive shaft 3 has 1. Hydrostatic bearings 6° 6' are provided on both sides of the drive gear 1, each acting as a thrust bearing.

Both the hydrostatic bearings 6 and 6' have the same structure, and each has an annular plate body 7 and 7' fixed to the side surface of the drive gear 1.
It is composed of annular blocks 9, 9' facing this plate-shaped body 7° 7' with small gaps 8, 8' interposed therebetween.

The annular blocks 9, 9' are fixed to the casing 10 side, and pockets 11, 11 are provided on the side opposite to the plate-shaped body 7.7'.
' is formed.

On the other hand, 15 is a hydraulic control device with built-in hydraulic equipment.

A pressure oil supply pipe 13, 13' that communicates with the hydraulic control device 15 via the throttle nozzle 12, 12' is connected to the pocket 11° 11' of the hydrostatic bearing 6, 6', and the hydraulic pressure is controlled. Pressure oil is supplied into the pockets 11 and 11', and most of it flows out through the gaps 8 and 8'.

In addition, the pockets 11, 11' have pressure oil outlet pipes 14,
14' are connected so that the hydraulic pressure in the pockets N1 and 11' is fed back to the hydraulic control device 15.

Since the above-mentioned transmission is refined from a gear train of helical gears, when the drive shaft 3 is rotated by the power of the prime mover 5,
Thrust is generated on the drive shaft 3 due to the engagement between the driving gear 1 and the driven gear 2, and a load is applied to the hydrostatic bearing 6 during normal rotation in the direction of the arrow, and to the hydrostatic bearing 6' during reverse rotation. .

At this time, a supply pipe 13 or 13' is supplied from the hydraulic control device 15 to the static pressure bearing 6 or 6' which is subjected to the thrust load.
Since the pressure oil is loaded through the
When the pressure oil in the pocket NL11' flows out through the gaps 8, 8', the oil film formed is in balance with the above-mentioned thrust.

This hydrostatic bearing has a fluid spring action and vibration damping action with non-linear rigidity characteristics, so even if torque fluctuations from the prime mover 5 enter the drive shaft 3, the torque fluctuations are converted into thrust fluctuations and the bearing remains static. It is buffered by the pressure bearing 6 or 6', smoothing torque fluctuations and at the same time damping vibrations.

Therefore, this hydrostatic bearing makes it possible to smooth fluctuating torque and prevent torsional vibration resonance without providing an elastic joint between the prime mover 5 and the drive shaft 3 of the transmission.

FIG. 3 shows an example of a hydraulic control circuit in the hydraulic control device 15 shown in FIG.

In FIG. 3, numeral 16 is a variable discharge type hydraulic pump driven by a morph 17, which pressurizes the pressure oil in the oil tank 19 and supplies it to the hydrostatic bearings 6, 6'.

An actuator 18 that senses and changes the pressure of the hydrostatic bearing 6 or 6' acts on the hydraulic pump 16, and controls the discharge amount of the hydraulic pump 16.

The oil passage on the discharge side of the hydraulic pump 16 is provided with a safety valve 20 and a check valve 21, and is further branched into two via an accumulator 22 that prevents oil pressure pulsation, and a solenoid valve 2.
3 to the hydrostatic bearings 6, 6'.

The above two oil passages. Among them, a high throttle 30 is provided in the oil passage leading to the hydrostatic bearing 6' to limit the amount of hydraulic pressure.

By switching the solenoid valve 23, the connection of the two branched oil passages to the fluid bearings 6, 6' is changed to the third one.
Connect them to the static pressure bearings on opposite sides from the state shown in the figure.

On the other hand, the pressure oil outlet pipes 14 and 14' connected to the pockets 11 and 11' of the hydrostatic bearings 6 and 6' are respectively provided with throttles 24 and 24'. It is now possible to obtain the temporal average value of the hydraulic pressure within '.

These outlet pipes 14 and 14' are each connected to the Tsulade valve 2.
5, one reaches the actuator 18, and the other reaches the pipe stop 26, so that the oil passage is closed.

In the state shown in FIG. 3, the outlet pipe 14 communicates with the actuator 18, and the outlet pipe 14' communicates with the line stop 26, but when the solenoid valve 25 is switched, the two lines are separated from each other. They will be connected in opposite directions.

The above-mentioned solenoid valves 23 and 25 are both designed to switch the flow paths in conjunction with the switching operation of the rotational direction of the drive shaft 3.

Further, each pipe line is provided with a pressure gauge 27, respectively.

Now, in the above hydraulic control circuit, solenoid valve 2
3 and 25 are respectively set in the positions shown in FIG. Thrust is generated, and the thrust acts such that the hydrostatic bearing 6 side is the load side and the hydrostatic bearing 6' side is the anti-load side.

In this case, the hydraulic pressure in the pocket 11 of the hydrostatic bearing 6 fluctuates in accordance with the fluctuation of the thrust, but its temporal average value is detected via the take-out pipe 14 and input to the actuator 18.

The aperture 24 provided in the extraction pipe 14 is connected to the pocket 1 described above.
This is to operate so that the temporal average value of the fluctuating pressure within 1 can be obtained.

The actuator 18 operates the hydraulic pump 1 based on the oil pressure fluctuation signal in the PokeSolo 1 inputted through the above-mentioned extraction pipe 14.
6 is controlled, and the controlled pressure oil is supplied to the static pressure bearing 6 via the check valve 21 and the solenoid valve 23.

Therefore, accurate pressure oil commensurate with the magnitude of thrust fluctuations caused by torque fluctuations is supplied to the hydrostatic bearing 6, preventing the resonance phenomenon of torsional vibration, and alleviating and smoothing the peak of fluctuating torque. become.

On the other hand, in the above control operation, the anti-load side static pressure bearing 6
′ is not receiving thrust, but if air gets into the hydraulic circuit when it is not receiving such thrust, when the drive shaft 3 is reversed and this hydrostatic pressure bearing 6′ becomes the load side, the static This means that an appropriate pressure cannot be applied to the pressure bearing 6'.

The high throttle 30 provided in the branch path to the hydrostatic bearing 6' side in front of the solenoid valve 21 allows a small amount of pressure oil to flow at all times while restricting the flow rate even when the hydrostatic bearing 6' is on the opposite load side. This acts to prevent air from entering the oil passage as described above.

When rotating the rotating shaft 3 in the direction opposite to the arrow direction shown in FIG. 3, the solenoid valves 23 and 25 are switched so that the hydrostatic bearing 6' side becomes the load side and the hydrostatic bearing 6 side becomes the anti-load side.
Each will perform the same actions as above.

As described above, the present invention transmits the power of the drive shaft to the driven shaft via a gear train of helical gears, and at least one of the drive shaft and the driven shaft has a thrust load side and a thrust side depending on forward and reverse driving. In a gear transmission equipped with two hydrostatic bearings that alternately switch to the opposite load side, a hydraulic pump whose discharge amount is controlled by detecting the hydraulic pressure of the load side hydrostatic bearing is attached to both the hydrostatic bearings. The flow paths are connected via switching valves so that they can be switched alternately, and a high restriction is provided in the flow path leading to the anti-load side static pressure bearing. It is possible to change the oil pressure of the load-side hydrostatic bearing in accordance with the fluctuating torque without using an elastic joint or the like, and to have the hydrostatic bearing prevent torsional vibration resonance and smooth the fluctuating torque at the same time.

In addition, a high restriction is installed in the flow path leading to the anti-load side hydrostatic bearing to constantly flow a small amount of pressure oil to prevent air from entering. Even if the changeover is made, the hydrostatic bearing can be brought into a normal adjustable state immediately after the changeover.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing essential parts of a gear transmission according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, and FIG. 3 is a hydraulic control circuit diagram of the same device. 1... Drive gear, 2... Driven gear, 3
... Drive shaft, 4 ... Driven shaft, 5 ...
...Motor, 6,6'...Static pressure bearing, 8,8
'...Gap, 11, 11'...Pocket, 12, 12'...Aperture nozzle, 13.1
3'... Supply pipe, 14, 14'... Output pipe, 15... Hydraulic control device, 16...
・Hydraulic pump, 18... Actuator, 22
・・・・・・Accumulator, 23.25・・・・・・
Solenoid valve (switching valve), 30...High throttle.

Claims (1)

[Claims] 1. The power of the drive shaft is transmitted to the driven shaft via a gear train of helical gears, and at least one of the drive shaft and the driven shaft is alternately moved to the load side and anti-load side of the thrust according to forward and reverse drive. In a gear transmission equipped with two hydrostatic bearings that can be switched, a hydraulic pump whose discharge amount is controlled by detecting the hydraulic pressure of the load-side hydrostatic bearing is alternately connected to both the hydrostatic bearings via a switching valve. A gear transmission device characterized in that the flow path is connected in a switchable manner and that a high restriction is provided in the flow path connected to the anti-load side hydrostatic bearing.