WO2008130063A1

WO2008130063A1 - Bevel gear-type non-step controllable speed reducer

Info

Publication number: WO2008130063A1
Application number: PCT/KP2008/000015
Authority: WO
Inventors: Nung Jun Tae; Yong Chol Kim
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-04-23
Filing date: 2008-04-23
Publication date: 2008-10-30
Anticipated expiration: 2009-10-23

Abstract

This invention relates to the bevel gear- type non-step controllable speed reducer. The structural feature is that it contains the driving shaft (1 ), the driven shaft (9), and two bevel gears (6,7), wherein one of two bevel gears (6) rocks in the connection with the driving shaft (1 ), and another is combined with the worm wheel (10),and the worm wheel (10) is engaged with the worm,and thus the worm shaft becomes the control shaft (11 ) so that the non-step speed reduction or non-step speed increase is provided according to the rotation direction and rotation speed of the control shaft (11 ). It can be used for continuous variable transmission (CVT) too.

Description

Bevel Gear-Type Non-Step Controllable Speed Reducer

Technical Field of the Innovation

This invention relates to a speed reducer, in particular to a bevel gear-type non-step controllable speed reducer which can provide, certain speed reduction, non-step speed reduction control, non-step speed increase control, overload adaptation control, remote control and automatic control.

Background of the invention

A variety types of speed reducers are currently available, of which gear reducers are most widely used in the world, including typically a spur gear reducer, a bevel gearing reducer, a worm reducer, a planetary gear reducer, a spiral gear reducer, and an eccentric planetary gear reducer etc.

International Patent Application PCT/ITO 1/00640 discloses a multistage planetary speed reducer with spur gear meshing.

European patent application 006839A2 teaches a two stage speed reducer having a primary reduction stage.

U.S. Patent 3,037,400 discloses a two sage reducer wherein an eccentric drives, through bearings, a stepped pinion which mates with a stationary ring gear and an output ring gear.

U.S. Patent 3,939737 discloses an arrangement wherein a stepped pinion is eccentrically driven by an input shaft, through bearings, for engagement with a fixed gear and an output ring gear.

U.S. Patent 4,235129 discloses an arrangement wherein the hub of an input pulley is the eccentric for driving a floating pinion that coacts with an output ring gear.

Chinese patent application 02153089.0 discloses a cycloid pin gear reducer. EP 0207206 A2 discloses a gearless speed reducer comprising first and second discs disposed to face each other so as to transfer the rotation of the former to the latter.

The conventional speed reducers are such that reduction ratio at one stage is relatively low, and therefore it is needed to increase the dimensions of gears and/or reduction stages of the reducers to gain a high reduction ratio. Generally, it has been conventional that increasing a reduction ratio incurs loss of transmission efficiency and deterioration of operation.

Moreover, -there does not exist any speed reducer having all the features of high reduction ratio, high transmission efficiency and self-locking which is an important requirement for a lifting device such as a winch. Furthermore, it is difficult to realize non-step speed reduction and increase control, overload adaptation control, remote control and automatic control . Summary of the invention

It is an object of the present invention to provide the bevel gear-type non-step controllable speed reducer which - has simple structure and high transmission efficiency and which can provide high reduction ratio in the first step. Another object of the invention is to provide the bevel gear-type non-step controllable speed reducer which can provide non-step speed reduction and speed increase control, overload adaptation control, remote control and automatic control. The structural character of the bevel gear-type non-step controllable speed reducer of the present invention is that it contains the driving shaft, the driven shaft, and two bevel gears ,wherein one of two bevel gears rocks in the connection with the driving shaft , and another is combined with the worm wheel ,and the worm wheel is engaged with the worm ,and thus the worm shaft becomes the control shaft so that the non-step speed reduction or non-step speed increase is provided according to the rotation direction and rotation speed of the control shaft. In one embodiment of the present invention it shows the bevel gear - type non-step controllable speed reducer which contains the fixed bevel gear and the rocking bevel gears ,wherein the rocking bevel gear rocks in the connection with the driving shaft, and the fixed bevel gear is combined with the worm wheel ,and the worm wheel is engaged with the worm ,and thus the worm shaft becomes the control shaft so that the non-step speed reduction or non-step speed increase is provided according to the rotation direction and rotation speed of the control shaft. Here, if outside of the fixed bevel gear, instead of the worm gearing, other suitable braking devices are used, the non-step speed reduction can be provided. Another character of the present invention is that it can provide the stop, the right rotation and left rotation of the said speed reducer, non-step ^"control, overload adaptation control, remote control and automatic control by connecting the operating motor to the control shaft and the control device to the operating motor . The said non-step controllable speed reducer can operate the machines with better flexible character than hydraulic driving. According to the character of the load change of the machines, each time when the load changes occur, impulse of the load change of the leading motor is delivered to the operating motor and thus it makes leading motor to drive always in a certain horsepower by changing the ratio of the speed reduction. Therefore, this character can lengthen the working life of the motor. If said non-step controllable speed reducer of the present invention is used instead of hydraulic gear in the machines which use hydraulic driving, it can have better character, because of the quickness of the movement.

Brief Description of the Drawings

For a fuller understanding of the invention, the reference should now be made to the detailed description thereof in conjunction with the accompanying drawings, wherein: Fig.l shows the structure of one embodiment of the bevel gear - type non-step controllable speed reducer.

Fig.2 shows the character of non-step speed reduction and non-step speed increase of bevel gear - type non-step controllable speed reducer. Fig.3 shows the schematic view about the overload adaptation control, the non-step control and automatic control of the bevel gear- type non-step controllable speed reducer.

Detailed Description of Preferred Embodiment

1. Fig.l is comprised of the driving shaft(l), the front cover(2), bearing slope sleeve(3), the body(4), universal joint(5), the rocking bevel gear(6), the fixed bevel gear(7), the front cover(8), the driven shaft(9), the worm wheel(lθ), and the control shaft(l l).

The driving shaft(l) is set to the front cover(2) so that it can freely rotate by connecting of two bearings. The bearing slope sleeve(3) is fixed at the end of the driving shaft(l) ,and the rocking bevel gear(6) is set to be rotated freely through the bearing.

The universal joint(5) is firmly set to rocking bevel gear(6), and the universal joint(5) is connected to the driven shaft(9) to be rotated freely in the space.

The front cover(2) and the back cover (8) are connected to the body(4) by the bolts. If the driving shaft(l) rotates, then the rocking bevel gear(6) rocks according to the rocking angle of the bearing guide sleeve, and the rocking bevel gear(6) rotates according to the tooth of the fixed gear(7).

The rotation of rocking bevel gear makes the driven shaft to rotate by the universal joint(5). Here, the ratio of the speed reduction I, I = Zi /(Zi - Zi) . Zi is teeth number of the rocking bevel gear, TJI is the teeth number of the fixed bevel gear.

The worm wheel(lθ) is firmly fixed to the fixed bevel gear(7),and the worm wheel is engaged with the control shaft(l l) by the worm, and it is structurally so comprised that the fixed bevel gear(7) can be done the rotation, stop and left rotation by the rotation of the control shaft.

The worm driving has the character the self-braking, therefore, the said speed reducer preserve the character of the self-braking as it is and the rotation of the control shaft gives no effect to the driving efficiency of the speed reducer.

Furthermore, when the rocking bevel gear (6) rotates, the power apply to the fixed gear (7) to make the rotation in the reverse direction of the rocking bevel gear (6) , so the worm driving can be operated with the operating motor of low-horsepower.

When the control shaft(l l) rotates, the rotation speed (m)of the driven shaft(9) is as follows; m' = m - k m r/min.

The ratio of the speed reduction is F= m/(ri2 - k m): m is the rotation speed of the driving shaft, m is the rotation speed of driven shaft of the designed speed reducer and m is the rotation speed of the control shaft. k is the amplification coefficient ,and the amplification ration, H= (m - k n3)/ni. In order to increase the capability of the non-step control, the parameter k should be selected so that to make k big.

If the body of the said speed reducer is converted to the winch drum, and the fixed bevel gear (7) is fixed to the dram, and the worm gearing is suitably combined to the driven shaft, then it can be used as non-step controllable winch in which the worm shaft becomes the control shaft.

2. The character of non-step control of said speed reducer

Fig.2 shows the character of non-step control of said speed reducer. Following examples are referred in order to consider the character of non-step control of the said speed reducer.

The parameters of the said speed reducer are as follows;

I = 49, the fixed bevel gear Ta= 48, the rocking bevel gear Zi = 49, the ratio of speed reduction of the worm = 36, the speed of the rotation = 1740 r/min. If with the above parameters the rotation speed of the control shaft 112 = 0, then ri3' =

35.51r/min, if ri2=1278.36, then 113'= 0 and if ri2=2556.72 r/min then 112= -35.51 r/min.

In fig.2, the interval a-b is the interval of the speed increase, the interval b-c is the interval of the speed reduction, and interval c-d is the interval of reverse rotation.

Here, when the operating motor is rotates in reverse, it belongs to the interval of a-b. In the above example, if m = 0 ~ 1278.36 r/min , it belongs to b-c, and if m =

1278.36 ~ 2556. 72 r/min, it belongs to interval c-d of the reverse rotation.

If m = 1278.36 r/min, the driven shaft is stopped.

• The precision grade of the rotation

In the case the bevel gear type- non-step controllable speed reducer designed and made with the above parameter requires the rotation speed of driven shaft m = 14.676666672 r/min, it could be operate at accurate 113' = 14.676666672 r/min if m is selected as 750 r/min.

That is, the accurate rotation speed, up to 10^~9 below the decimal point can be provided, so it contributes to the development of nano-science and technology.

3. Overload adaptation non-step controllable speed reducer

The speed reducer of the present invention can provide the overload adaptation control.

Fig.3 shows the schematic view of the principle for the overloading adaptation control.

In fig.3, it is comprised of the driving shaft(l), the control shaft(2), and the driven shaft (9) of the said bevel gear type- non-step controllable speed reducer, the control lines(12) and(13), the operating motor and the control device.

The driving motor is connected to the driving shaft(l) , the operating motor is connected to the control shaft(2).

The control device is connected to the driving motor and the operating motor through the control lines (12),and(l 3ϊ By such principle , the accident of the motor by the overloading at driven shaft can be prevented without men's watch and the control.

By comprising such as in fig.3, the overload adaptation non-step controllable speed reducer can operate the working machines, with more softness character than hydraulic driving.

As shown in fig.3, each time when the load-change of working machine occurs, the impulse of the load-change is delivered to the operating motor, and then the rotation of the driven shaft is reduced in correspondence with the characteristic curve and thus the driving motor operates always only under fixed horsepower. Therefore, the working life of the motor can be very longer.

In said control system the operating motor is in the status of the stop if the operating motor operates in the status of normal load and it begins the rotation with the proportional speed to the overloading horsepower from the moment that the overloading occurs in operating motor. The operating motor is selected according to the calculation and its horsepower is very lower than the driving motor.

The speed control can be done by amplitude-phase control mode. Preferred embodiments of the present inventions have now been described; however, the changes will obviously occur to those skilled in the art without departing from the spirit thereof.

It is therefore, intended that the invention is to be limited only by the scope of the appended claims

Claims

Claims.

1. The bevel gear - type non-step controllable speed reducer is characterized in that it contains the driving shaft, the driven shaft, and two bevel gears ,wherein one of two bevel gears rocks in the connection with the driving shaft , and another is combined with the worm wheel ,and the worm wheel is engaged with the worm ,and thus the worm shaft becomes the control shaft so that the non-step speed reduction or non-step speed increase can be provided according to the rotation direction and rotation speed of the control shaft.

2. The bevel gear - type non-step controllable speed reducer according to the claim 1 is characterized in that it is comprised of the driving shaft(l), the front cover(2), bearing slope sleeve(3), the body(4), universal joint(5), the rocking bevel gear(6), the fixed bevel gear(7), the front cover(8), the driven shaft(9), the worm wheel(10),and the control shaft(l 1), wherein

- the movement combination of the driven shaft(9) and the rocking bevel gear(6) is done by the universal joint(5); and

- the combination of the driving shaft(l) and the rocking bevel gear(6) is done by the bearing slope sleeve; and

- the driving shaft(l) is set to the front cover(2) so that it can rotate by connecting of two bearings; and - the universal joint(5) is firmly set to rocking bevel gear(6), and the universal joint(5) is connected to the driven shaft(9) to be rotated freely in the space; and

- the fixed bevel gear(7) is set to be freely rotated on the driven shaft(9), and the worm wheel(lθ) is fixed rigidly to the fixed bevel gear(7); and - the control shaft(l l) is engaged with worm wheel by the worm.

3. The said speed reducer according to the claims 1 or 2 is characterized in that if other suitable braking devices are used instead of the worm gearing, the non- step speed reduction can be provided.

4. The said speed reducer according to the claims 1 or 2 is characterized in that it can provide non-step control, overload adaptive control, remote control, automatic control and high precise grade of the rotation if the driving motor is connected to the driving shaft(l), the operating motor is connected to the control device through the control line(12),and the control device is connected to the driving motor through the control line(13).

5. The said speed reducer according to the claims 2 is characterized in that it can be used as non-step controllable winch if the body of the said speed reducer is converted to the winch drum, and the fixed bevel gear (7) is fixed to the drum, and the worm gearing is suitably combined to the driven shaft, and thus the worm shaft becomes the control shaft.