JPS5939620B2 - Locked train transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a locked train transmission.

More specifically, the present invention relates to a locked train transmission that eliminates load fluctuations due to gear machining errors, significantly improves power transmission efficiency, and prevents torsional vibrations.

A locked train has a structure in which the power of the input shaft is distributed to multiple intermediate shafts by the first stage gear train, and the power of these multiple intermediate shafts is simultaneously collectively transmitted to the output shaft by the second stage gear train. Due to its characteristics, it is often used as a transmission for large horsepower vehicles.

This is because when changing the speed of the input shaft, the power is distributed to multiple intermediate shafts, so the load on each intermediate shaft is reduced, and the size of each gear for power transmission is therefore reduced. This is because the device as a whole can be made compact due to the advantages such as being able to be miniaturized and being able to arrange the input and output shafts on the same axis. .

In addition, since the load on each intermediate shaft is reduced, the module of the power transmission gear can be made smaller, which enables the diameter of the gear to be made smaller and the circumferential speed can be reduced, which is also advantageous in reducing noise. This is because it has the feature of being

However, the above-mentioned locked train has a configuration in which power is simultaneously transmitted from one input shaft to multiple intermediate shafts, and the power from these multiple intermediate shafts is collectively transmitted to one output shaft at the same time. Therefore, in order for smooth power transmission to occur through this locked train, all gears in the first and second stage gear trains must mesh properly at all times, and the load must be applied to each intermediate shaft. It is necessary to ensure that it is evenly distributed.

However, it is inevitable that there will be some errors in the machining of the gears and their phase settings, and this machining error will cause unequal distribution of the load to each intermediate shaft.

This unequal distribution causes noise and vibration generation and reduces power transmission efficiency.

On the other hand, when connecting a prime mover with torque fluctuations, such as a diesel engine, to a reduction gear, torsional vibrations due to torque fluctuations occur at the rotational speed where the resonance point occurs.
Generally, an elastic joint is interposed between the prime mover and the speed reducer to absorb torque fluctuations.

In other words, at the resonance point of torsional vibration, a force several times the normal transmission torque is applied to the tooth surface of the gear, which would damage the shaft or gear without an elastic joint.

Therefore, countermeasures against torque fluctuations are an important issue, particularly in vessels that use large-horsepower diesel engines.

However, the method using elastic joints is currently in practical use as it can cover the limited torque salt, but in the case of high torque ranges above a certain level, elastic joints that can absorb the torque fluctuations have to be manufactured. Currently, it has not been put into practical use due to the expected difficulties in doing so.

The purpose of the present invention is to solve the problem of locked trains caused by gear machining errors as described above, easily avoid load fluctuations on gear tooth surfaces due to machining errors, and distribute the load evenly to each intermediate shaft. It is an object of the present invention to provide a transmission using a locked train that enables distribution and prevents torsional vibration due to fluctuations in input torque.

The present invention achieves the above object by distributing the power of the input shaft to a plurality of intermediate shafts by a first-stage gear train, and simultaneously transmitting the power of the plurality of intermediate shafts to the output shaft by a second-stage gear train. In a locked train transmission for collective transmission, the first stage gear train and the second stage gear train are arranged such that the torsional directions of the teeth are opposite to each other, and the torsional directions of the teeth are opposite to each other, and the gear train is positioned at both ends of the intermediate shaft. A screw member is provided, and the intermediate shaft can be adjusted to move in the axial direction by screwing the screw member, and both ends of the intermediate shaft and the input shaft are elastically supported in the axial direction by hydrostatic bearings, and the static pressure is The bearing is configured to continuously supply a specified amount of pressure oil through a throttle nozzle to form an oil film that maintains a constant thickness against fluctuations in thrust, and to receive thrust in the axial direction through this oil film. It is characterized by this.

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

1 to 6 show an embodiment in which a locked train transmission according to the present invention is configured as a speed reduction device.

In FIG. 1, 1 is an input shaft, and 2 is an output shaft.

The input shaft 1 is rotatably supported by a casing 3 via a plain bearing 4.degree. 5 so as to be able to move slightly in the thrust direction.

The input shaft 1 and the prime mover (not shown) may be coupled to each other as long as they have a structure that allows slight movement of the input shaft 1 in the thrust direction, such as a gear coupling.

On the other hand, the output shaft 2 is connected to the casing 3 with a bearing 6.
It is rotatably supported by 7.

A pinion helical gear 8 is fixed to the input shaft 1, and a plurality of intermediate shafts 10 are connected to the pinion helical gear 8.
A plurality of helical gears 9 fixed to each of the helical gears 9 are in mesh at the same time.

A plurality of intermediate shafts 10, preferably 2 to 4, are provided,
The helical gear 9 fixed to each intermediate shaft 10 has a larger number of teeth than the pinion helical gear 8, thereby decelerating the power of the input shaft 1 and distributing it to the plurality of intermediate shafts 10. There is.

The pinion helical gear 8 and helical gear 9 are
It constitutes the gear train of the second stage.

On the other hand, a pinion helical gear 11 is fixed to the other end side of the plurality of intermediate shafts 10, and the plurality of pinion helical gears 11 are connected to a helical gear 12 fixed to the output shaft 2.
are engaged at the same time.

The pinion helical gear 11 constitutes a second stage gear train that decelerates the power of the plurality of intermediate shafts 10 and collectively transmits it to the output shaft 2 at the same time.

Both ends of each intermediate shaft 10 are supported by plain bearings 13 and 14 relative to the casing 3, respectively, so as to be able to move slightly in the thrust direction.

The torsion direction of the helical gear 8°9 in the first stage gear train and the helical gear 11.1 in the second stage gear train.
The twisting directions of No. 2 are set to be opposite to each other.

At both ends of each intermediate shaft 10, hydrostatic bearings 29 are provided, each of which is loaded with pressure oil at a constant pressure.
Details of its structure are shown in FIGS. 2-3.

Similarly, static pressure bearings 19 are provided on both sides of the input shaft 1 at the position where the pinion helical gear 8 is fixed, and the details of the structure are shown in FIGS. 5 and 6.

First, the static pressure bearing 29 will be explained.
As shown in the figure, a disk-shaped plate 3 is provided on the end surface of the intermediate shaft 10.
0 is fixed by a bolt 31.

On the other hand, a block 32 faces this plate-like body 30 with a small gap 37 interposed therebetween.

The block 32 is provided with a pocket 34 that opens toward the plate state 30 side, and a throttle nozzle 35 that communicates with this pocket 34 is provided at the oil supply port.

The throttle nozzle 35 is further connected by a joint 33 to an oil supply conduit 36.

Further, the pocket 34 communicates with the outside via a conduit 39, and a pressure gauge 41 is provided at the end of the conduit 39 via a cock 40.

The block 32 is fitted and held by a screw member 42 that is screwed into the casing 3 so that it can move forward and backward.

Therefore, when installing the block 32, the screw member 4
2, the screw member 42 is screwed into the casing 3, and the screw member 42 is locked with a lock nut 43 at an appropriate position.

After installing the block 32 in this manner, a joint 33 connects a refueling conduit 36.

This oil supply conduit 36 is connected to a oil supply pump 102 driven by a motor 101, and has a hydrostatic bearing 29.
The pocket 34 is supplied with pressure oil.

As for the static pressure bearing 19 provided on the input shaft 1, as shown in FIGS.
It is fixed by 21.

On the other hand, a small gap 27.2 with respect to this plate-shaped body 20.20
7 are interposed between the annular blocks 22,
22 are fixed to the casing 3 by bolts 23, 23, respectively.

Block 22.22 has an annular space pocket l-24,2
4 are provided, and the opening of each pocket 1-24.24 faces the plate-shaped body 20.20.

The block 22.22 is further provided with a throttle nozzle 25.25 at the refueling port communicating with the pocket 24.24, through which a further refueling conduit 26.26 is connected. .

After the conduits 26 and 26 are combined, they are connected to a fuel pump 102 driven by a motor 101.

The oil supply pump 102 supplies oil overflowing from the gap 27 of the hydrostatic bearing 19 and the gap 37 of the hydrostatic bearing 29 to the conduit 10.
3 and again via conduit 26.26 to the pocket 24 of the hydrostatic bearing 19 and the pocket 3 of the hydrostatic bearing 29.
4. Make sure to force feed each of them.

These hydrostatic bearings 19 and 29 elastically support the axial thrust generated in the input shaft 1 and the intermediate shaft 10, respectively, by the spring action of the oil film.

The screw members 42 and 42 located at both ends of each intermediate shaft 10 are screwed into the casing 3, so that the intermediate shaft 1
It is now possible to spiral in the direction of the zero axis.

Therefore, by appropriately adjusting the screw members 42° 42 and moving the position, the end of the intermediate shaft 10 can be pressed, and the rest position of the intermediate shaft 10 can be slightly moved in the axial direction.

Therefore, by using this screw member 42, the meshing contact between the teeth of all the gears in the first stage gear train and the second stage gear train can be completely established as an initial condition before starting operation with a simple structure. Can be matched.

This kind of screwing operation of the screw member 42 uses a torque wrench set to a constant torque value, and when the set torque value is reached, the screwing of the screw member 42 is automatically stopped. , the screw member 42 is slightly returned so as to create an appropriate gap for forming an oil film on the hydrostatic bearing.

The pressure gauges 41, 41' are for detecting the pressure inside the pocket 34 of the hydrostatic bearing 29, and it becomes possible to know the pressure inside the pocket during operation and read the load sharing of each intermediate shaft 10.

When there is an intermediate shaft with an uneven load, by rotating the screw member 42 corresponding to the intermediate shaft and moving it forward and backward in the axial direction, the intermediate shaft can be moved in the axial direction and the equal distribution of the load can be completely adjusted. can do.

Now, as mentioned above, since machining errors in gear machining are virtually unavoidable, conventional locked train transmissions are constructed with a complex structure including a hollow intermediate shaft, a flexible shaft, a gear coupling, etc. However, as explained below, this device has an extremely simple structure and exhibits excellent performance.

The locked train transmission device of the present invention described above has the following features:
As mentioned above, the helical gear 8 in the first stage gear train
, 9 and the helical gears 11, 12 in the second stage gear train are opposite to each other.

Therefore, when this transmission is operated, the direction of the thrust on the intermediate shaft 10 by the first stage gear train and the direction of the thrust on the intermediate shaft 10 by the second stage gear train are the same direction, and the direction of the thrust on the intermediate shaft 10 by the second stage gear train is the same. The sum of both thrusts will act, but the first thrust will act on the movement in the axial direction.
This is extremely effective in this respect, since relief from contact between the tooth surfaces of the first stage gear train and the second stage gear train is formed at the same time.

That is, as shown in FIG. 7, in the first stage gear train, the tooth flank relief amount corresponding to δ corresponds to the axial movement amount l, and in the second stage gear train, at the same time, δ' This means that the desired amount of tooth surface relief can be obtained.

Also, since δ-1 sin α, δ' = l sin α', if the sum of tooth flank relief is D, then D2l (sin α + sin α'), and if l is constant, α
, α' becomes larger, the clearance of the tooth surface becomes larger with respect to the movement of the intermediate shaft, and the equalization of load distribution becomes easier.

In addition, vibrations are absorbed by the hydraulic spring action of the hydrostatic bearing.

Unlike the naturally occurring oil film that occurs on general plain bearings, the oil film on hydrostatic bearings has its rigidity adjusted in advance by the pressure oil load from the pump and the effect of the throttle nozzle installed at the oil filler port. Therefore, a wide range of adjustment is possible, and the effect is particularly great when applied to a large horsepower transmission.

In addition, hydrostatic bearings do not cause fatigue like mechanical springs, so they are very effective for high horsepower applications. The thrust does not change, it always has a hydraulic spring action that corresponds to the magnitude of the thrust, and it does not generate vibrations due to elastic recovery, making it possible to adjust thrust fluctuations in an extremely stable manner.

In addition, in the above device in which the static pressure bearings 29 are provided at both ends of the intermediate shaft 10 and the static pressure bearing 19 is also provided on the input shaft 1 which is movable in the axial direction, the load on each intermediate shaft 10 is unequal. In addition to correcting the arrangement, it is also possible to simultaneously damp large torque fluctuations caused by resonance of torsional vibrations based on torque fluctuations of the prime mover.

In other words, the torque fluctuation generated in the prime mover is caused by the input shaft 1 and the intermediate shaft 1 in the gear train of the first stage helical gear.
This fluctuation occurs as a fluctuation in the thrust of 0, but this fluctuation occurs when the static pressure bearings 19 and 29
．． 37, that is, the oil film thickness will automatically change and be absorbed.

At this time, the ratio of the amount of thrust fluctuation to the mass of the object that slightly moves in the thrust direction is clearly larger for the input shaft 1, which has only one small pinion helical gear, than for the intermediate shaft 10, so the thrust direction fluctuation of the input shaft 1 has greater followability.

Therefore, most of the fluctuation torque is absorbed by the fluctuation of the input shaft 1, and the intermediate shaft plays an auxiliary role.

Although the above-mentioned embodiment illustrated a speed reduction device, the present invention can be similarly applied to a speed increase device.

As described above, the present invention distributes the power of the input shaft to a plurality of intermediate shafts by the first stage gear train, and simultaneously collects the power of the plural intermediate shafts to the output shaft by the second stage gear train. In a locked train transmission that is intended to transmit
The twisting directions of the teeth of the first stage gear train and the second stage gear train are opposite to each other, and screw members are provided at both ends of the intermediate shaft, and the screw members are screwed. The intermediate shaft is movable and adjustable in the axial direction, and both ends of the intermediate shaft and the input shaft are elastically supported in the axial direction by hydrostatic bearings, and the hydrostatic bearings supply a predetermined pressure oil through a throttle nozzle. Continuous oil supply forms an oil film that maintains a constant thickness against fluctuations in thrust, and the oil film receives thrust in the axial direction. Although the thrust of the first stage gear train and the thrust of the second stage gear train act in the same direction, a large tooth flank relief is easily formed due to the movement of the intermediate shaft.
Since it is supported by the hydrostatic bearing having the above configuration, it is effective to avoid variations in the tooth surface load due to machining errors.

In addition, it is possible to reduce the amount of movement l of the intermediate shaft in order to obtain a certain amount of tooth flank clearance necessary to avoid errors, and therefore the helix angle of the first stage gear train can be made relatively small. Multiple of the number of intermediate shafts (usually 2 to 4 times)
This allows the structure to be configured without overpowering the thrust force of the input pinion gear, which generates thrust.

Since such an input shaft is further supported by a hydrostatic bearing, resonance of torsional vibration caused by high torque fluctuations of the prime mover can be effectively damped without using an expensive elastic joint or the like.

In addition, screw members are provided on both ends of the intermediate shaft, and by screwing the screw members, the intermediate shaft can be moved and adjusted in the axial direction. This makes it possible to easily adjust the meshing of each gear, and to load This makes it possible to further enhance the effect of evenly distributing resources.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a transmission device according to an embodiment of the present invention;
2 is a longitudinal cross-sectional view of a static pressure bearing at the end of the intermediate shaft in the device, FIG. 3 is a cross-sectional view taken along line I-1 in FIG. 2, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 5 is a longitudinal sectional view of the hydrostatic bearing of the input shaft in the above device, and FIG. 6 is a sectional view taken along line Vl-VI in FIG. FIG. 7 is a schematic diagram illustrating the meshing situation of the tooth surfaces on the intermediate shaft of the above device. 1...Input shaft, 2...Output shaft, 3...
... Casing, 8... Pinion helical gear, 9... Helical gear, 10...
Intermediate shaft, 11...Pinion helical gear, 12
... Helical gear, 19, 29 ... Static pressure bearing, 42 ... Screw member.

Claims (1)

[Claims] 1. The power of the human power shaft is distributed to a plurality of intermediate shafts by a first-stage gear train, and the power of the plurality of intermediate shafts is simultaneously collectively transmitted to the output shaft by a second-stage gear train. In the desired locked train transmission, the first stage gear train and the second stage gear train have teeth twisted in opposite directions, and screw members are provided at both ends of the intermediate shaft. , the intermediate shaft can be adjusted to move in the axial direction by screwing the screw member, and both ends of the intermediate shaft and the input shaft are elastically supported so as to be movable in the axial direction by hydrostatic pressure bearings, and the static pressure The bearing is constructed so that it receives thrust in the axial direction by continuously supplying a predetermined pressure oil through a throttle nozzle to form an oil film that maintains a constant thickness against fluctuations in thrust. A locked train transmission characterized by: 2. A locked train transmission according to claim 1, wherein the locked train is a speed reduction mechanism. 3. The locked train transmission according to claim 1, wherein the locked train is a speed increasing mechanism.