CN1074739A

CN1074739A - Stepless speed variator

Info

Publication number: CN1074739A
Application number: CN 92100352
Authority: CN
Inventors: 颛清平
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-01-21
Filing date: 1992-01-21
Publication date: 1993-07-28

Abstract

The stepless speed variator of two kinds of structural types, but the mechanical fricting stepless transmission of on-stream continuous stepless speed governing belonged to, comprising supporting wheel, output wheel, speed ring, circular cone wheels, cone pulley retainer and the input shaft that connects with it are coaxial line input, output.Utilization planetary gear train and rolling friction transmission principle with circular cone crop rotation planet wheel, are realized the stepless speed regulation of output wheel by the axial position that changes speed ring.This type speed changer has very wide scheduling scope, and zero rotating speed and big torque output are arranged, and can carry out constant-power speed regulation, is easy to realize automatic control, is applicable to the stepless speed regulation of middle low power.Its gear ratio is

Description

Stepless speed variator

The present invention is a stepless speed variator, but belongs to the mechanical fricting stepless transmission of on-stream continuous stepless speed governing, is applicable to the transmission of middle low power.

Different with general mode of speed regulation, the present invention uses planetary gear train and rolling friction transmission principle, with circular cone crop rotation planet wheel, by changing the axial position of speed ring, realizes the stepless speed regulation of output shaft.

The stepless change scheme that the present invention is intended to propose is simple in structure, reliable, have zero rotating speed and big torque output, can carry out constant-power speed regulation, thereby the stepless speed variator that makes middle low power is easy to design, manufacturing and working service, is used widely in relevant field.

Summary of the invention:

As shown in Figure 1 and Figure 2, this drive train is a 3K-H type planetary gear train.Among the figure: 1 for supporting wheel, be central gear K ₁; 2 is output wheel, i.e. central gear K ₂; 3 is speed ring, i.e. central gear K ₃; 4 is conical wheel (group), makes planet wheel; 5 is the cone pulley retainer, makes tie-rod H; 6 is input shaft, connects with 5.

1. feature

The geometric center lines of supporting wheel, output wheel, speed ring, input shaft and cone pulley retainer or the revolution axis of rotational axis and conical wheel are same straight line, are called main axis.In train, circular cone crop rotation planet wheel is symmetrically distributed on the cone pulley retainer for a plurality of, and each wheel all is parallel to main axis with respect to the outer surface bus of main axis; The cone pulley retainer is made tie-rod, connects with input shaft, passes to the circular cone wheels rotatablely moving, and makes it produce corresponding revolution motion; Supporting wheel freely turns round, and supports conical wheel; Speed ring can not rotate or swing, and can only make it produce parallel to an axis by its control mechanism to move in that train is in service, thereby output wheel is carried out stepless speed regulation; Supporting wheel, output wheel and speed ring, they with conical wheel between be and contact and the rolling friction transmission.

As shown in Figure 1 and Figure 2, the effective radius R of supporting wheel, output wheel and speed ring ₁, R ₂, R ₃Increase successively.The conical wheel point of contact radius R that contacts with speed ring ₄₃Maximum value R _43maxGreater than the conical wheel point of contact radius R that contacts with output wheel ₄₂; The circular cone wheel face that contacts with output wheel is ring-type indent conical surface or ring plain, and the circular cone wheel face that contacts with speed ring is an outer conical surface, and above-mentioned inner conical surface drift angle is greater than the male cone (strobilus masculinus) drift angle, and when the inner conical surface drift angle was 180 °, this face was ring plain; The output wheel surface that contacts with conical wheel is the ring-type convex globoidal; With perimeter surface in the speed ring that conical wheel contacts is the ring-type convex globoidal.

In Fig. 1, the conical wheel point of contact radius R that contacts with supporting wheel ₄₁Less than the conical wheel point of contact radius R that contacts with output wheel ₄₂, two corresponding surface of contact of supporting wheel and conical wheel are respectively ring-type convex globoidal and ring-type concave arc surface.

In Fig. 2, the conical wheel point of contact radius R that contacts with supporting wheel ₄₁Greater than the conical wheel point of contact radius R that contacts with output wheel ₄₂, two corresponding surface of contact of supporting wheel and conical wheel are respectively ring-type concave arc surface and ring-type convex globoidal.

2. speed change analysis

As shown in Figure 1 and Figure 2, represent that with arrow certain takes turns the peripheral velocity direction of viewable side, R ₁, R ₂And R ₃Be respectively the effective radius of wheel for inputting, output wheel and speed ring; R ₄₁, R ₄₂And R ₄₃Be respectively the conical wheel point of contact radius that contacts with wheel for inputting, output wheel and speed ring.From the output terminal direction, when wheel for inputting rotates by counter clockwise direction, input shaft drives conical wheel along side roll in the speed ring by the cone pulley retainer that connects with it, promptly produce around the spinning motion of self axis with around the revolution motion of main axis, and revolution speed equals the input shaft rotating speed.Output wheel produces and rotatablely moving that conical wheel adapts under the effect of circular cone wheels.The axial position of change speed ring can obtain different rotating speeds from output terminal.Output terminal and input end switched in opposite.

Form planetary gear train by tie-rod 5, planet wheel 4, speed ring 3 and output wheel 2, this train gear ratio is

R= (n ₂)/(n ₁) =1- (R ₃·R ₄₂)/(R ₂·R ₄₃)

Output speed is

n ₂=(1－ (R ₃·R ₄₂)/(R ₂·R ₄₃) )·n ₁

In the formula: n ₁Be the wheel for inputting rotating speed.

R ₄₃Be Variable quantity, along with the axial position difference of speed ring, R ₄₃Excursion is 0～(R ₃)/(R ₂) R ₄₂, work as R ₄₃→ 0 o'clock, R →-∞, n ₂→-∞, at this moment, there is the self-locking problem in mechanism;

R ₄₃=(R ₃)/(2R ₂) R ₄₂The time, R=-1, n ₂=-n ₁;

R ₄₃→ (R ₃)/(R ₂) R ₄₂The time, R → 0, n ₂→ 0, at this moment, mechanism may produce self-locking.

Analyze as can be known, the absolute value of gear ratio and output speed is with R ₄₃Increase and reduce, with R ₄₃Reduce and increase, its excursion is all ∞～0; And work as R ₄₃=(R ₃)/(2R ₂) R ₄₂The time, output equates that with input speed direction is opposite.

3. output characteristics

With mechanism shown in Figure 1 is that example is carried out force analysis, and Fig. 3 is its force analysis figure.F among the figure ₁, F ₂And F ₃Be respectively the contact counter-force of conical wheel to supporting wheel, output wheel and speed ring.As seen, work as F ₁One regularly, F ₂/ F ₁And F ₂With R ₄₃Increase and increase, with R ₄₃Reduce and reduce.

If part material performance etc. satisfies the bearing capacity requirement, energy consumption is disregarded, and under certain friction factor, according to principle of conservation of energy, works as R ₄₃Hour, output speed is higher, and the maximum load torque that output wheel can bear is less, in requisition for less circumference frictional force with contact counter-force F ₂; In like manner, work as R ₄₃When big, output speed is lower, in requisition for bigger contact counter-force F ₂And discuss as can be known by epimere, this mechanism just can satisfy this and change requirement, that is: if F ₁Necessarily, work as R ₄₃Hour, F ₂/ F ₁Less, F ₂Get smaller value; Work as R ₄₃When big, F ₂/ F ₁Bigger, F ₂Get higher value.Like this, when factors such as part material performance met the demands, permanent power transmission can be done by this mechanism in certain power range.Consider the energy consumption that is caused by sliding friction etc. in the real-world operation, this permanent power transmission has certain approximation.

Work as R ₄₃→ (R ₃)/(R ₂) R ₄₂The time, output speed n ₂→ 0, by principle of conservation of energy, disregard energy consumption, the maximum load torque that output wheel can bear is answered → ∞.But part material performance at this moment and friction factor etc. have just constituted decisive restraining factors, the torque that can only transmit a maximum, i.e. breakdown torque T _Max

Equally, can similarly analyze, can draw identical output characteristics result mechanism shown in Figure 2.

Output characteristic curve as shown in Figure 4.

Compare with the existing mechanical Variable Speed Technology, adopt stepless speed variator of the present invention that very wide speed adjustable range is arranged, zero rotating speed and big torque output are arranged, and can carry out constant-power speed regulation; Carry out speed governing by the axial translation control mechanism, can be in operation process adjust at any time, simple and convenient; Be easy to realize automatic control; Simple in structure, compact, volume is little, can be used for various middle low power speed governing occasions; Because material, manufacturing and related factors influence such as lubricated should not be used for the high-power speed-adjusting occasion.

Fig. 5 implements a scheme of the present invention: power passes to circular cone wheels 4 by input shaft 6 by cone pulley retainer 5, transmission by planetary gear train, under the effect of supporting wheel 1 and speed ring 3, transmission of power is given output wheel 2, is delivered on the output shaft 8 by contact pressure controlling mechanism 7 again.Pull handle 9, make speed ring produce axial translation, thereby realize the stepless speed regulation of output shaft.

Enforcement the present invention should also be noted that:

1. select proper lubrication oils to make traction fluid, guarantee between each point contact movement pair to be traction transmission, elastohydrodynamic lubrication, be beneficial to slow down wearing and tearing, improve transmission efficiency and working life.

2. according to actual requirement, it is adjustable to guarantee that relevant contact force is designed to.

3. for adapting to different usage requirements, the axial translation mechanism of speed ring can be designed to manually or control automatically.

4. design the time is selected speed adjustable range according to actual needs, and avoids the self-locking problem that may occur in the mechanical operation.

Claims

1, the stepless speed variator of two kinds of structural types, according to planetary gear train and the design of rolling friction transmission principle, but be the mechanical fricting stepless transmission of on-stream continuous stepless speed governing, it is characterized in that: comprise supporting wheel, output wheel, speed ring, circular cone wheels, cone pulley retainer and the input shaft that connects with it; Supporting wheel, output wheel, speed ring, cone pulley retainer reach the geometrical center of the input shaft that connects with it or the revolution axis of rotational axis and conical wheel is same straight line, is called main axis; In train, circular cone crop rotation planet wheel is symmetrically distributed on the cone pulley retainer for a plurality of, and each wheel all is parallel to main axis with respect to the outer surface bus of main axis; The cone pulley retainer is made tie-rod, connects with input shaft, passes to the circular cone wheels rotatablely moving, and makes it produce revolution motion; Supporting wheel freely turns round, and supports conical wheel; Speed ring can only be done parallel to an axis and move, and regulates output speed; Supporting wheel, output wheel and speed ring, they with conical wheel between be and contact and the rolling friction transmission.

2, by the stepless speed variator of claim 1, it is characterized in that: the effective radius of supporting wheel, output wheel and speed ring increases successively, and the maximum value of the conical wheel point of contact radius that contacts with speed ring is greater than the conical wheel point of contact radius that contacts with output wheel; The circular cone wheel face that contacts with output wheel is ring-type indent conical surface or ring plain, and the circular cone wheel face that contacts with speed ring is an outer conical surface, and the inner conical surface drift angle when the inner conical surface drift angle is 180 °, is ring plain greater than the male cone (strobilus masculinus) drift angle; The output wheel surface that contacts with conical wheel is the ring-type convex globoidal; With perimeter surface in the speed ring that conical wheel contacts is the ring-type convex globoidal.

3, by the stepless speed variator of claim 1 and 2, it is characterized in that: the conical wheel point of contact radius that contacts with supporting wheel is less than the conical wheel point of contact radius that contacts with output wheel; Two corresponding surface of contact of supporting wheel and conical wheel are respectively ring-type convex globoidal and ring-type concave arc surface.

4, by the stepless speed variator of claim 1 and 2, it is characterized in that: the conical wheel point of contact radius that contacts with supporting wheel is greater than the conical wheel point of contact radius that contacts with output wheel; Two corresponding surface of contact of supporting wheel and conical wheel are respectively ring-type concave arc surface and ring-type convex globoidal.