RU2578797C2 - Design of infinitely variable unit with master link drive via levers and variable point of external rotation forces application - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: infinitely variable unit comprises master and slave links. The master link can contain a pinion, a sprocket or a wheel with drive levers rigidly connected across their rotation axis. The drive levers move the sliders that transmit the torque via a variable radius. Upon the displacement of the controlled slider the driven sliders move. The suggested diagram of the infinitely variable unit drive ensures the use of the cylindrical or a bevel gear drive, as well as a flexible drive - chain, belt or friction one.

EFFECT: simplified design.

8 cl, 7 dwg

Description

The device of a stepless variator with a drive of the leading link through levers and a variable point of application of external rotation forces

Technical field

The invention relates to devices for stepless regulation of gear ratios when transmitting rotational motion from one body to another. A device that transmits rotation from one master shaft to another, the slave, is called transmission. It can be used, for example, in the field of vehicles, engineering, as well as in instrumentation, etc.

State of the art

Known friction variator in the invention SU 1516687 A1 (Chernyaev B.N., 10.23.1989), comprising a housing, a drive and a driven coaxial shafts. A carrier has been fixed to the drive shaft. On the spline driven shaft, the central wheel moves with an inner conical surface, which can be displaced along the axis of the driven shaft. Between the master and the driven coaxial shafts there is an inclined axis, which in the middle is divided into two parts and rests on spherical joints. On the drive shaft, the end of the inclined axis is spring-loaded and pressed against the carrier.

On the driven shaft, the second end of the inclined axis, due to its loading on the drive shaft, transmits torque to the contact point of the conical surface of the central wheel due to friction forces.

The change in the gear ratio of the variator is achieved due to the axial displacement of the inner conical surface of the central wheel, which leads to a change in the radius of rotation of the driven shaft. This variator is selected as a prototype of the proposed technical solution.

The first disadvantage of this device is that it provides one type of drive - friction. The use of friction gears is limited to medium and low powers, since at high moments, the pressing forces increase accordingly and the gears get significant dimensions.

The second disadvantage of this device is that the torque is transmitted from the drive shaft to the driven shaft through one inclined articulated axis, which reduces the transmitted power.

Another disadvantage is that inside the inclined surface the change in the radius of the drive is limited and this reduces the range of regulation of the gear ratio.

In technology, transmission is carried out mainly mechanically through a series of contacting moving parts. As a rule, the speed of the engine and the working body are not equal to each other. The coordination of these speeds is carried out using gears with the conversion of speeds and loads.

All mechanical gears are divided into two groups: - gearing gearing (gear - cylindrical; bevel; worm; chain, etc.); as well as friction gears (friction and belt).

The types of cylindrical gears include: planetary, wave, rack and pinion.

Speed control can be discrete (step) - in this case, the gearbox is called a gearbox or gearbox, as well as stepless (smooth) - such a mechanism is called a variator. In the transmission, the rotational speeds of the driven and driving shafts are usually different, therefore the ratio of these speeds is called the gear ratio - i.

The rotational speeds of the output shaft in the speed gearboxes are obtained by introducing into gearing various pairs of gears.

The simplest gear mechanism consists of two gears, the drive wheel is called a gear, the driven one is simply a wheel.

Stepless transmission (variator) - a mechanism that allows you to smoothly change the gear ratio of the rotational speeds n ₁ and n ₂ on its driven and drive shafts.

, гдеThe continuously variable mechanical gears are mainly based on the use of friction gears or gears with flexible coupling: in them different values of the gear ratios i = n ₁ / n _{2 are} achieved due to a smooth change in the ratio of the radii in the contact of the driving and driven links, i.e. $$i_{1.2}=\frac{{\omega }_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="\omega "\; filenames="00000014.png"\; state="\{\{state\}\}">\omega </figure-callout>}}_2}=\pm \frac{R_2}{R_{\mathrm{one}}}$$

where

ω ₁ - the angular velocity of the leading link;

ω ₂ - the angular velocity of the driven link;

R ₁ is the radius of the leading link;

R ₂ is the radius of the driven link.

The gear ratio of the friction gear is equal to the ratio of the diameter of the driven wheel to the diameter of the drive wheel. The speeds of the points in the place of contact (contact) of the disk due to friction of the wheels in the absence of slippage will be the same.

It is known that gear mechanisms are the most numerous type of rotation transmission mechanisms due to the constant gear ratio, contact, durability and high reliability, the ability to transmit large powers.

Therefore, only a continuously variable gear transmission or a flexible transmission can be considered promising.

SUMMARY OF THE INVENTION

The technical result of the invention is to increase the efficiency of the transmission, expand the range of regulation of gear ratios and the ability to use a universal drive of the drive and driven shafts in the form of separate, independent gears: tooth, chain, belt or friction with two gear ratios.

In accordance with the title of the invention, “The device of a stepless variator with a drive of the drive link through the levers and a variable point of application of external rotation forces”, the adopted technical solution is based on the interaction of two separate coaxial links.

The first link in the drive splined shaft, spline coupling with hinged rods and sliders at the end change the point of application of external rotation forces. This is due to the fact that when the slotted coupling is displaced along the spline shaft, the hinge rods change the radius of rotation of the sliders, i.e. the sliders can approach or move away from the shaft axis.

The second link in the invention consists of a gear (option), a disk (levers) with guides for the sliders of the first link, rigidly fixed to the shaft and having independent support. Here, the diameter of the gear (wheel) is less than the diameter of the disk (levers). Therefore, it is possible to schematically present a gear as a lever with a constant shoulder (radius of rotation), and a drive disk as another lever along which the point of application of external rotation forces changes. In this case, we obtain a composite lever, in which one shoulder is constant equal to the radius of the gear (wheel), and the other with a variable radius of rotation, i.e. closer to the axis or further from the axis of the shaft.

Alternating torque from the leading link of rotation is transmitted to the driven bodies of rotation of different diameters. Here the second stage of the formation of gear ratios on the parallel shafts of the drive and driven wheels. Various types of gears can be installed on parallel shafts: gear, chain, belt or friction.

In the proposed variator, stepless regulation of gear ratios is achieved in two ways. The first method is through obtaining on a rotating link in the form of a disk with guides for sliders with hinged rods, gears (wheels) on the shaft, i.e. creating an unequal lever with a common axis of rotation, where one shoulder is constant, equal to the radius of the leading body of rotation, and the other variable is equal to the radius of the disk (lever). Due to the fact that the drive of the driving link is organized through a variable (movable) point of application of external rotation forces, we therefore obtain a variable gear ratio. It is explained by the law of Archimedes, which determines that: "The ratio of the displacements of the two ends of the lever to which the forces are applied is always inverse to the ratio of the forces applied to these ends."

. Значит, для того чтобы "золотое правило" было справедливо для двойного блока, должно быть выполнено условие: $$\frac{F_1}{F_2}=\frac{r_2}{r_1}$$

. Тогда силы F₁ и F₂ уравновесятся и, значит, блок должен либо покоиться, либо двигаться равномерно.For example, during the rotation of the double block (Fig. 3 Scheme of the gate), the ends of the ropes wound on fastened together (common axis) blocks of radii r ₁ and r _{2 will} move to distances S ₁ and S ₂ proportional to these radii: $$\frac{S_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="00000014.png"\; state="\{\{state\}\}">S</figure-callout>}}_2}=\frac{r_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="00000014.png"\; state="\{\{state\}\}">r</figure-callout>}}_2}$$

. So, in order for the “golden rule” to be true for a double block, the condition must be met: $$\frac{F_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="F"\; filenames="00000014.png"\; state="\{\{state\}\}">F</figure-callout>}}_2}=\frac{r_2}{r_{\mathrm{one}}}$$

. Then the forces F ₁ and F _{2 will be} balanced and, therefore, the block must either rest or move uniformly.

In the proposed variator, you can imagine the leading link, as part of the disk (levers), as an analogue of a double block. Here, the constant shoulder is the radius of the leading link, and the variable shoulder is the radius of the disk (levers), i.e. point of application of external rotation forces. The difference is that in the double block both radii are constant, therefore their gear ratio is constant.

In the variator, the ratio of the constant radius - the leading body of rotation to the variable radius on the disk forms a variable gear ratio on the drive link, i.e. a variable at the end of the leading body of rotation.

The second method is due to the transfer of the variable peripheral speed of the leading body of rotation to the driven body of rotation of a different diameter. Here, the interaction of equal arms of rotating bodies, but of different diameters also form a gear ratio.

In the proposed variator, the overall gear ratio of the two stages will be equal to their product.

In technology, the lever is an element of many modern devices: in scissors, blocks, gears, in the front wheel drive of a bicycle and many others.

. В связи с тем, что пара вращающихся тел имеет постоянные радиусы, поэтому передаточное отношение пары остается постоянным.A pair of external gear wheels in contact at point P rotate in opposite directions with angular velocities ω ₁ and ω ₂ inversely proportional to the radii r ₁ and r ₂ and the number of teeth Z ₁ and Z ₂ : $$\frac{{\omega }_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="\omega "\; filenames="00000014.png"\; state="\{\{state\}\}">\omega </figure-callout>}}_2}=\frac{r_2}{r_{\mathrm{one}}}=\frac{Z_2}{Z_{\mathrm{one}}}$$

. Due to the fact that the pair of rotating bodies has constant radii, therefore the gear ratio of the pair remains constant.

The technical idea of the variator is based on the use of the laws of leverage, the properties of which were mathematically substantiated by Archimedes.

Archimedes' law (Fig. 2) on the balance of the lever shows that the force acting on the left (short) shoulder of the lever F ₂ is n times greater than the force F ₁ acting on the right shoulder (long).

.The path S ₂ traveled by the point of application of force F ₂ will be n times greater than the path S ₁ traveled by the point of application of force F ₁ . Here, the ratio of the displacements of the two ends of the lever to which the forces are applied is always inverse to the ratio of the forces applied to these ends. The relationship is recorded: $$\frac{S_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="00000014.png"\; state="\{\{state\}\}">S</figure-callout>}}_2}=\frac{F_2}{F_{\mathrm{one}}}=\frac{r_2}{r{}_{\mathrm{one}}}$$

.

This creates a gear ratio on the lever.

или $$i_{12}=\frac{{\omega }_1}{{\omega }_2}$$

; $$i_{21}=\frac{{\omega }_2}{{\omega }_1}$$

,There are several definitions of gear ratio. For example, the gear ratio of the speed of one link of a mechanism to the speed of another link, unless specifically stated otherwise, is the speed of the input link to the speed of the output link. Designate as $$i_{12}=\frac{v_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="v"\; filenames="00000014.png"\; state="\{\{state\}\}">v</figure-callout>}}_2}$$

or $$i_{12}=\frac{{\omega }_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="\omega "\; filenames="00000014.png"\; state="\{\{state\}\}">\omega </figure-callout>}}_2}$$

; $$i_{21}=\frac{{\mathrm{<figure-callout\; id="2"\; label="\omega "\; filenames="00000014.png"\; state="\{\{state\}\}">\omega </figure-callout>}}_2}{{\omega }_{\mathrm{one}}}$$

,

where: v - linear (peripheral speeds);

ω are the angular velocities of the links with indices corresponding to these links, in which:

1 - input link, 2 - output link.

Distinguish gear ratio of the gear, as the ratio of the number of teeth of a large wheel Z ₂ to the number of teeth of a smaller wheel (gear): $$u=\frac{Z_2}{Z_{\mathrm{one}}}$$

;Another variant of the gear ratio is distinguished, as the ratio of force (for progressively moving links) or rotational moment at the output link of the mechanism, respectively, to the force or moment at the output link of the mechanism, taken with the opposite sign: $$i=\frac{F_2}{F_{\mathrm{one}}}=-\frac{T_2}{T_{\mathrm{one}}}=i\eta$$

;

where: F ₁ and F ₂ , T ₁ and T ₂ - forces and moments, respectively, at the input (1) and output (2) links; i - gear ratio - the ratio of the speed of the input link to the speed of the output link; η is the efficiency of the mechanism. On the lever, as on the body of rotation, you can get a variable gear ratio. This is due to the fact that the gear ratio depends on the point of application of force.

Consider the cases:

a) leverage

In this case, both ends of the lever make equal paths and their ratio is equal to unity, therefore linear speeds at the ends are equal.

b) the lever of unequal shoulders

In this case, the long end of the lever makes a long way, and the short end of the lever has a smaller path, so the ratio of the shoulders is not equal to one (more or less than one).

In practice, an unequal arm is used when the point of application of an external force is at a constant point between the axis of rotation and the rim of the rotating body.

For example: in a locomotive wheel and in a wheel of a front wheel drive of a bicycle. In this case, the long shoulder of the wheels of the engine and bicycle accelerate the movement of these bodies along the path (road). This is a variant of the constant gear ratio of the lever, because shoulder ratio is constant.

Another example of a bicycle wheel drive: here, the application of external force is at a point that is further away than the radius of the rotating body, but also the shoulder is constant.

The bike uses different lengths of connecting rods, which affect the transmission of effort from the legs of the cyclist to the wheel. To calculate the gear ratio, it is necessary to take the ratio of the circumference of the wheel to the circumference described by the connecting rod and multiply by the gear ratio of the chain mechanism. Thus, the bicycle drive is described in its entirety, from the pedal to the bicycle wheel.

In this drive mechanism, the gear ratio is the ratio of the number of wheel revolutions per one pedal revolution.

There is the concept of laying or the step of a cyclist - this is the distance that a bike travels for one pedal in this gear.

The smaller the styling, the better the traction of the bike in a given gear, but less speed.

However, a number of devices are known in which the application of external mobile forces on an unequal arm is used, i.e. on its long part. For example, steelyard - lever scales. This mechanism is a lever with unequal shoulders. One shoulder is short (constant), and the second shoulder is long, along which the reference load can be moved with a fixed position.

Here on the long shoulder of the lever, with your hands you can change the point of application of the external rotation force. In this way, the moments of strength on different shoulders are balanced.

Another example, a vertical collar is a capstan. Here the capstan spokes are long shoulders and it becomes possible to change the point of application of external rotation forces along the lever arm (manually, without a mechanism).

External forces (Fig. 1) - forces acting on the points of the material system from the points and bodies that do not belong to this system.

Examples of external forces: the force of the feet on the bicycle pedal, the force of the hands on the handle of the winch drive, etc. In connection with this, the goal is to create a mechanism for transferring external rotation forces to the drive link in the disk with guides for sliders with articulated movable rods that provide transmission torque through a variable radius.

To implement this idea, we propose a technical solution and obtain a variable gear ratio (at the first stage of the variator) on the drive wheel and the disk (levers) combined with it.

Strength is the main measure of mechanical action on the body. During rotation, the action of force on the body is determined by the point of its application. A force acting on a body fixed on an axis can only cause rotation when the direction of the force does not pass through the axis. To rotate the body, it is necessary to apply a force perpendicular to the radius. During rotation, the action of force on the body is determined by the point of its application.

The line of action of a force is the line along which a force acts.

The arm of force d is the distance from the axis of rotation to the line of action of the force.

The moment of force with respect to the M axis is a scalar quantity characterizing the rotational action of the force equal to the product of the force modulus F acting on the solid and the shoulder of the force d of this force relative to this axis

M = Fd

A pair of forces is a system of two equal masses of forces acting on a solid body that are parallel and directed in opposite directions. The shortest distance d between the action lines of a pair’s forces is called the pair’s shoulder. Under the influence of a pair of forces, a free body will rotate. When applying simple mechanisms (lever, block, gate, etc.) it was revealed that movements in a very definite way are associated with forces developed by the mechanism. It was found that the ratio of displacements S of the two ends of a simple mechanism to which the forces are applied is always inverse to the ratio of the forces F ₁ , F ₂ applied to these ends (Fig. 2).

There are two types of levers. At the lever of the 1st kind, the fixed support point is located between the lines of action of the applied forces, and at the lever of the 2nd kind it is located on one side of them.

When rotating a round body, one can schematically consider the rotation of a lever with equal and unequal shoulders.

A certain modification of the double block is the gate, as well as the capstan (vertical gate) (Fig. 3 Scheme of the gate).

It is known that to obtain a significant speed of movement on the wheels of a steam locomotive, a simple mechanism in the form of an unequal lever was used. On the driving wheels, its moving part (rim) was connected with the long end of the lever equal to the radius of the wheel. The connecting rod of a steam locomotive presses with great force on the short arm of the crank (with a constant arm). The connecting rod gives the rim points a higher speed than the speed at the connecting rod bearing connected to the piston.

We will call another example of using an unequal lever to accelerate movement - a bicycle. Here, a pair of external forces is applied to the sprocket on the axis of the wheel with a constantly short lever arm and already the speed of the bicycle V is equal to the linear speed of the wheel with a large lever arm.

$$V=\pi Dn\cdot \frac{Z_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="00000014.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2}$$

where - D is the diameter of the wheel,

n is the speed of the pedals,

Z ₁ - the number of teeth of the leading gear.

Z ₂ - the number of teeth of the driven gear.

The "golden rule of mechanics" is observed quite accurately with uniform movement (without friction). In order to obtain a gain in strength, different combinations of blocks are used, for example, a double block (Fig. 3). It consists of two blocks of different radii, rigidly fastened together and mounted on a common axis. The shoulders of the forces (the radii of the blocks R and r) are different in this case, i.e. the double block acts as an unequal lever. The equilibrium conditions of the double block are the same as the unequal lever FR = Pr or $$\frac{F}{P}=\frac{r}{R}$$

           The double block can also be considered as a force transducer. And here, applying a small force to a block of a larger radius, we can get a large force acting on a block of small radius. During the rotation of a solid (lever), the velocity vector V is directed tangentially to the described point of the circle in the direction of motion, which coincides with the direction of the arc arrow of the angular velocity. The velocity vectors of all points of the cross section perpendicular to the axis of rotation will be located in its plane, forming a velocity field (Fig. 4).

Note that:

The velocity vectors of the points are perpendicular to the straight lines connecting the points to the axis of rotation, and are directed towards the rotation of the body (ω).

The velocity modules of the points of a rotating body are proportional to their distance from the axis of rotation.

The speed V of the point of a rotating body is sometimes called the linear or circumferential speed of the point, in contrast to the angular velocity of the body.

V = ω

where ω is the angular velocity;

R is the radius of rotation.

On (Fig. 4) shows the speed field, which shows that if the lever, whose shoulders are equal, then the speeds at its ends will be equal (V _a = V _in ). If the shoulders of rotation are not equal to AO> OS, then the peripheral speeds of these shoulders will not be equal to V _a > V _c at the end of the lever with a long shoulder, the peripheral speed is greater, but on the short shoulder less, because the speed depends on the radius of their rotation (at a common angular velocity).

So, the unequal lever allows you to gain strength in the short shoulder or have high speeds at the long end of the lever. Given these properties of the lever, we consider a device diagram in which two gears are located on parallel axes and are engaged (Fig. 5). Kinematic scheme of the drive of the driven link of the variator (a variant of the gear cylindrical or friction gear). We take one gear 1 for the leading, and the other 2 for the driven. To the end face of the drive gear 1 (transverse to the axis), we fix the lever 3 protruding beyond the diameter of this gear. On the lever 3 we place the slider 4, which has the ability to move along the lever 3 and mount on it.

In this drive circuit of the driven link 2, we got an unequal lever on the driving link 1, interacting with the driven gear 2 of radius r ₂ . In this case, we take into account that two equal forces F ₁ and F ₂ act on opposite sides of the axis of rotation and are directed opposite to each other. These two forces create a torque of a pair of forces F ₁ and F ₂ with a shoulder equal to the sum of these two radii of rotation. Consider the action of each force separately. The shoulder R _{2 of the} external force F ₁ on the lever 3 can be changed, and the other shoulder on the same lever at point B for the force F ₁ will be constant and equal to the radius of the driving link R ₁ (equal to the radius of the gear or wheel). For an external force F ₂ located on the other side of the axis on the lever 3, the shoulder will be equal to the shoulder R _{2 of the} force F ₁ . This shoulder R _{2 of} force F ₂ can also vary, but the other shoulder on the same lever at point C for force F ₂ will be constant and equal to the radius of the leading link R ₁ .

It is known that at the contact point of gears or wheels, the circumferential speeds of rotation of the bodies are the same. However, their gear ratio depends on the diameters of the interacting gears (wheels).

In the proposed variator, the drive of the driving link (gears, wheels) is carried out through an unequal arm when one arm of the arm is equal to the radius of the driving link and the other arm of the arm changes, i.e. it can be greater or less than the radius of the leading link. As a result of such a drive, we obtain a variable speed at the crown of the leading link with a constant rotation arm. This is due to a change in the radius of the rotation drive when the points of application of external rotation forces are located on the other end of the link arm. The resulting variable speed at the crown of the driving link is transmitted to the driven link due to engagement or friction and changes its angular velocity. In this case, the gear ratio will depend on the variable speed at the end of the lever with a constant arm of the driving link and the ratio of the diameters (radii) of the interacting gears (wheels) of the driving and driven links.

Description of the drawings.

In FIG. 1-6 indicated:

FIG. 1. The action of force at uniformly accelerated rotation

FIG. 2. The ratio of the movement of the two ends of the lever

FIG. 3. Gate layout

FIG. 4. The velocity field of a rotating body (lever)

FIG. 5. Kinematic diagram of the drive of the driven link of the variator (cylindrical or friction)

FIG. 6. The drive circuit of the driven link of the variator through a flexible transmission

FIG. 7. The device of a stepless variator with a drive link through levers and a variable point of application of external rotation forces

When calculating the kinematic characteristics of various points of a rotating body in the formulas V = ω.R and ∈ = a _t / R; circumferential velocity and angular acceleration for a given moment in time, the same values of the angular velocity ω and angular acceleration ∈ will be substituted, since they are characteristics of the motion of the whole body. Where R is the radius of rotation, and _t is the tangential acceleration. Both of these values depend on the radius of rotation. The angular path or rotation angle ϕ of the rotating body also depends on the radius, the larger the radius, the greater the value of the tangential acceleration a _t = ∈R = 2nr, where n is the number of revolutions.

If the acceleration is directed in the same direction as the speed, then the movement is called uniformly accelerated, and if directed in the opposite direction of speed, then - equally slow.

Determine the speed V ₁ at the contact point A (Fig. 5) of the interacting gears (wheels) using the speed formula V = ωR where ω is the angular velocity, R is the radius of rotation. Here it must be taken into account that during rotation of the body the general condition of equality ω ₁ = ω ₂ = ω of the angular velocities of the drive lever is preserved, i.e. to the axis of rotation and after the axis of rotation, as well as the equality ∈ ₁ = ∈ ₂ = ∈ of angular accelerations. This general condition is preserved both with uniform and equally variable rotation.

Since the angular velocity is equal to ω = V / R, with the equality ω ₁ = ω ₂ = ω, the relations are V ₁ / R ₁ = V ₂ / R ₂ and V ₁ = V ₂ R ₁ / R ₂

and accordingly, the speed V ₂ is equal to V ₂ = V ₁ R ₂ / R ₁

where V ₁ is the speed at the point of contact of the leading link with the slave;

V ₂ - speed at the point of application of external forces, at the other end of the lever;

R ₁ is the radius of the leading link (constant lever arm);

R ₂ is the radius of rotation at the point of application of external forces at the other end of the lever (variable).

If the ratio of the radii R ₁ / R ₂ is equal to one, then the speeds are equal to V ₁ = V ₂ .

If the ratio of the radii R ₁ / R _{2 is} greater than unity, then the speed V ₁ will be greater than the speed V ₂ .

If the ratio of the radii R ₁ / R ₂ is less than unity, then the speed V ₁ will be less than the speed V ₂ .

Having determined the speed V ₁ at the contact point of the interacting gears (wheels), one can find the number of revolutions n _{2 of the} driven link n ₂ = V ₁ / 2πR ₂

Where - 2πR ₂ - the circumference of the driven link, depending on the diameter.

Knowing the number of revolutions of the driving link n ₁ and the driven link n _2, you can determine the gear ratio i · i = n ₁ / n ₂

We can make a general conclusion that it is real to get a variable peripheral speed at the contact point of the leading and driven links. This is possible due to the drive circuit of the drive link through the levers. In this case, one part of the lever is equal to the radius of the leading link, and the second part of the lever is under the influence of external forces, the point of application of which along the shoulder changes. In this regard, when the radius of the applied forces is less than the radius of the driving link, the peripheral speed at the point of contact of the driving and driven links will increase. When the radius of the applied external forces is greater than the radius of the driving link, the peripheral speed at the point of contact of the driving and driven links will decrease.

As a result of the proposed drive, the constant arm of the driving link will rotate at different (peripheral) speeds. This variable peripheral speed is transmitted to the slave link. The ratio of the angular velocities of the driving and driven links gives a variable gear ratio.

Note that the drive circuit of the driving link through the levers and the variable point of application of external rotation forces preserves the principle of operation of the variator. In this case, it is possible to use a cylindrical or bevel gears, as well as flexible (chain, belt) (Fig. 6) or friction gears.

The implementation of the invention

In the variator device (Fig. 7), a drive of the driving link is introduced as part of a disk with guides for the slide (levers) 10 and the body of revolution 11 from two separate coaxial drive shafts 1 and 13.

The drive link 10, 11 is rigidly fixed to the second drive shaft 13. The disk with guides for the sliders (levers) 10 has a diameter that is larger than the diameter of the drive link 11 and they are parallel to each other. The torque from the driving spline shaft 1 with the coupling 4 and the movable rods 7 and 8, and the sliders 9 at the end is transmitted to the disk 10. The sliders 9 are moved in the vertical plane due to the long movable rods 7 and short 8. Long rods 7 are twice as much as short 8 The short rods 8 are pivotally connected to the support 3 of the first drive shaft 1.

The position of the sliders 9 can be fixed by a controlled slider 17 located on the movable splined sleeve 4 and located on the leading spline shaft 1. The controlled slider 17 allows you to change the radius of rotation of the drive link 10, 11, which is located on the second drive shaft 13. The displacement of the sliders 9 in the disk ( lever) 10 changes the torque, peripheral speed and creates variable gear ratios on the driving body of rotation 11, in accordance with the Archimedes law on the lever. The alternating torque from the driving rotary body 11 is transmitted to several driven rotational bodies 14 of different diameters, but smaller than the diameter of the driving body 11. The driven bodies 14 rotate on the shafts 15, in the bearings 16 of the housing and are located in parallel around the second drive shaft 13.

In the variator, a universal drive is proposed, which allows you to set various types of gears in place of the driving rotation body 11 and driven 14: gear, chain, belt or friction. These gearing options do not change the operating principle of the variator. This is a description of the second stage of the formation of variable gear ratios on the link: the leading and the driven bodies of revolution.

The device of the variator as a part of two gear stages provides a general range of variables of controlled gear ratios and their equal production.

The device operates as follows

When moving the clutch 4 along the first driving spline shaft 1 towards the driving link 10, 11, the rods 7 and 8 due to the hinges 5 and 6 move the sliders 9 in the grooves of the disk 10. The torque is transmitted through the sliders 9, the disk 10 to the second drive shaft 13 and the leading body of rotation 11 (Fig. 7).

Due to the fact that the position of the sliders 9 can be controlled, i.e. the rotation radius of the drive of the driving link 10, 11 can be fixed, then the moment of external forces of rotation will also change, depending on the radius of the drive.

Suppose that the arm of the moment of external rotation forces (sliders 9) is equal to the radius of the driving rotation body 11. In this case, the peripheral speed of the crown of the driving rotation body 11 will be equal to the peripheral speed of the sliders 9.

Here the diameters are equal at equal angular velocity. The gear ratio here is determined only by the ratio of the diameter occupied by the sliders and the rotation body 11, i.e. it will be equal to unity in this case.

In the case of the position of the sliders 9, when the diameter is larger than the diameter of the driving body 11, the condition of the unequal arm operates. Here, the shoulder of the drive of the drive link with the guides 10 will be larger than the shoulder (radius) of the drive wheel 11 itself, i.e. at a common angular speed, but different radii, the peripheral speed of the slider 9 will be greater than the peripheral speed of the crown of the driving wheel 11. In this case, the driving wheel 11 transfers the driven wheel 14 a smaller circumference speed, and the speed of the driven wheel 14 is reduced. However, the gear ratio of the drive 11 and the driven wheels 14 is taken into account as additional. The overall gear ratio will be equal to the product of their steps.

Let us consider the third variant of the position of the sliders 9, when due to the movement of the control slide 17, the sliders 9 will occupy a position in the middle of the radius of the drive wheel 11. Here, the drive arm of the drive link with the guides 10 will be less than the shoulder (radius) of the drive wheel 11 itself, i.e. at a common angular speed at a larger radius of the driving wheel 11, the peripheral speed will be greater than the peripheral speed of the sliders 9. In this case, the driving wheel 11 transfers the driven wheel 14 a large peripheral speed, and the speed of the driven wheel 14 increases, but the overall gear ratio of the driving and driven wheels is taken into account as a product of two steps.

Information sources:

1. The invention of SU 1516687 (Chernyaev B.N.), 10.23.1989.

2. I.I. Artobolevsky. “Mechanisms in modern technology”, Volume 3, M: Nauka, 1973, p. 457, mech. 573.

3. G.S. Landsberg. Elementary textbook of physics. Volume 1. Mechanics. Fizmatlit 2000

4. A.F. Krainev. Dictionary reference to mechanisms. Moscow "Engineering" 1981

Claims (8)

1. The device is a stepless variator with a drive of the drive link through levers and a variable point of application of external rotation forces, containing the drive and splined coaxial shafts, as well as a gear ratio control mechanism, characterized in that a splined coupling with hinges and rods moves on the splined drive shaft with bearings pivotally connected to each other and with the coupling, as well as with the support of the drive shaft, while at the ends of the rods are placed sliders on hinges that move in the guide rails or along the levers sharp mutually perpendicular directions due to the rotation of the rods when moving the controlled slider on the splined shaft, which changes the point of application of external rotation forces, and the disk or levers are rigidly connected to the drive link of the variator and located coaxially with the drive shaft on the support, where the diameter of the disk or levers exceeds the diameter drive link and transmits alternating torque to driven shafts arranged parallel to the axis of the drive link, in addition, two stages of gear ratios are applied in the variator, one due to a change radius to drive the driving member on the basis of the properties of the lever, and the second stage is provided by the difference in diameters of interacting gears or transmission wheels. 2. The variator according to claim 1, characterized in that the driven and driving links can be made in the form of gears or sprockets, i.e. in the form of independent gears. 3. The variator according to claim 1, characterized in that it creates variable gear ratios due to the separate use of gear, bevel, as well as flexible or friction gear at the place of interaction of the leading and driven links. 4. The variator according to claim 1, characterized in that it is possible to install one or more driven shafts parallel to the axis of the drive shaft. 5. The variator according to claim 1, characterized in that gear wheels or sprockets of different diameters are installed on the driven shafts. 6. The variator according to claim 1, characterized in that two stages of the gear ratio are formed initially on the crown of the drive wheel due to its drive through levers and a variable point of application of external rotation forces, as well as due to the difference in diameters of the driving and driven interacting wheels. 7. The variator according to claim 1, characterized in that the gear ratio is controlled on the spline drive shaft by displacing the spline coupling with rods and sliders at their end along the axis of the drive shaft. 8. The variator according to claim 1, characterized in that the gear ratio is controlled by a controlled slider located on the splined shaft of the drive.

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