CN101592210A - A method of constant power transmission - Google Patents

Abstract

The present invention relates to a method of constant power transmission, assuming that the load torque on the output shaft of the transmission box is T(t), the rotational speed of the input shaft is n _i , the rotational speed of the output shaft is n _o , and the transmission ratio is i(t) , the power of the output shaft is P, then P=2πn _o ×T(t)=2πn _i ×i(t)×T(t), that is, i(t)=P/(2πn _i ×T(t)), When the load torque T(t) changes with the load, the transmission ratio i(t) changes accordingly, so that the power P of the output shaft remains unchanged. According to the above formula, the drive wheel connected to the input shaft and the output shaft The driven wheels connected with the shafts adopt variable parameter transmission wheels with conjugate meshing. By adopting the method, the weight of the equipment can be effectively reduced, and the labor consumption and construction cost of the equipment can be reduced.

Description

A method of constant power transmission

Technical field:

The invention relates to a transmission method, in particular to a constant power transmission method.

Background technique:

In a reciprocating lifting machine such as an oil field pumping unit, the load changes during the lifting process, such as: the load is large during the lift, and the load is small during the return. This makes the torque on the transmission box output shaft fluctuate. The traditional fixed-ratio transmission determines that the speed of the output shaft is a constant, so the actual power required is a variable, so in the actual work process, the motor can only be equipped according to the maximum power. In order to solve the problem of transmission power change when the load changes, the method of reverse counterweight is adopted. When the load is large, the counterweight moves downward, and when the load is small, the counterweight moves upward. The movement of the counterweight is used to balance part of the load change. This method cannot realize complete constant power transmission, and the counterweight will also increase the weight and labor consumption of the equipment, and increase the construction cost. Here it is the weak point that existing technology exists.

Invention content:

The purpose of the present invention is to provide a method capable of realizing constant power transmission under variable load conditions to address the shortcomings of the prior art.

This program is realized through the following technical measures: In the method of constant power transmission, set the load torque on the output shaft of the transmission box as T(t), the speed of the input shaft is n _i , and the speed of the output shaft is n _o , the transmission ratio is i(t), and the power of the output shaft is P, then P=2πn _o ×T(t)=2πn _i ×i(t)×T(t), namely $i\left(t\right)=\frac{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A2009100166430008H1.png"\; state="\{\{state\}\}">P</figure-callout>}}{{2\mathrm{\&pi;n}}_i\&times;T\left(t\right)},$ When the load torque T(t) changes with the load, the transmission ratio i(t) changes accordingly, so that the power P remains constant. According to the above formula, the drive wheel connected to the input shaft and the drive wheel connected to the output shaft The driven wheel adopts the variable parameter transmission wheel with conjugate meshing.

The driven wheel connected with the above-mentioned output shaft is an eccentric roller wheel, and the driving wheel connected with the input shaft adopts a variable parameter cycloidal gear which is conjugated with the driven wheel.

The profile shape of above-mentioned driving wheel and driven wheel is determined according to the following steps: (1) according to the change of load and according to the formula $i\left(t\right)=\frac{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A2009100166430008H1.png"\; state="\{\{state\}\}">P</figure-callout>}}{{2\mathrm{\&pi;n}}_i\&times;T\left(t\right)}$ Determine the transmission ratio i(t); (2) Determine the center distance between the input shaft and the output shaft according to the load and strength requirements; (3) Determine the center position of each roller on the roller wheel, the number of rollers, and the outer diameter of the rollers. (4) Solve the tooth shape of the drive wheel according to the principle of conjugate meshing.

According to the formula $x_i=x_{\mathrm{oi}}-r_r\frac{{\mathrm{the\; y}}_{\mathrm{oi}}^{\&prime;}}{\sqrt{{x_{\mathrm{oi}}^{\&prime;}}^2+{{\mathrm{the\; y}}_{\mathrm{oi}}^{\&prime;}}^2}},$ ${\mathrm{the\; y}}_i={\mathrm{the\; y}}_{\mathrm{oi}}+r_r\frac{x_{\mathrm{oi}}^{\&prime;}}{\sqrt{{x_{\mathrm{oi}}^{\&prime;}}^2+{{\mathrm{the\; y}}_{\mathrm{oi}}^{\&prime;}}^2}}$ Calculate the center coordinates of each roller, where x _i and y _i are the coordinates of the roller profile curve, r _r is the radius of the roller, x _oi and y _oi are the coordinates of the center of the roller; x _oi = acosθ+r _di cos(θ _io +θ), y _oi = a sinθ+r _di sin(θ _io +θ), where a is the center distance between the input shaft and the output shaft, r _di is the center of the roller to the axis of the roller wheel The distance, θ _io is the initial position angle of the roller, θ is the angle between the point on the roller profile curve and the line connecting the center of the cycloid gear and the x-axis.

The rollers on the driven wheel are distributed with equal central angles.

The rollers on the above-mentioned driven wheels adopt rolling bearings, sliding bearings or bearing pins.

The above-mentioned rollers are cylindrical or conical.

The drive wheel connected with the above input shaft can also be an eccentric roller wheel, and the driven wheel connected with the output shaft can be a variable parameter cycloidal gear that is conjugated with the drive wheel.

The beneficial effect of this scheme can be known from the description of the above-mentioned scheme. In the method of constant power transmission, the driving wheel located on the input shaft and the driven wheel located on the output shaft are in conjugate engagement, and the driving wheel adopts a variable parameter cycloid Gear (or eccentric roller wheel), driven wheel adopts eccentric roller wheel (or variable parameter cycloid gear). transmission ratio $i\left(t\right)=\frac{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A2009100166430008H1.png"\; state="\{\{state\}\}">P</figure-callout>}}{2{\mathrm{\&pi;n}}_i\&times;T\left(t\right)},$ The speed n _i of the input shaft is a constant value; when the load increases, the load torque T(t) on the output shaft increases, and the transmission ratio i(t) decreases accordingly, so that the power P of the output shaft remains When the load decreases, the load torque T(t) on the output shaft decreases, and the transmission ratio i(t) increases accordingly, so that the power P of the output shaft remains unchanged, thus realizing the variable Constant power transmission of the system under load. By using the method, the counterweight block can be omitted, the weight of the equipment is reduced, and the labor consumption and construction cost of the equipment are reduced. It can be seen that, compared with the prior art, the present invention has outstanding substantive features and remarkable progress, and the beneficial effects of its implementation are also obvious.

Description of drawings:

Fig. 1 is a schematic diagram of a transmission structure in a specific embodiment of the present invention.

Among the figure, 1 is an input shaft, 2 is a driving wheel, 3 is an output shaft, 4 is a driven wheel, and 5 is a roller.

Detailed ways:

In order to clearly illustrate the technical characteristics of this solution, the following will describe this solution through specific implementation modes and in conjunction with the accompanying drawings.

A method of constant power transmission, assuming that the load torque on the output shaft of the transmission box is T(t), the rotational speed of the input shaft is n _i (n _i = constant), the rotational speed of the output shaft is n _o , and the transmission ratio is i (t), the power of the output shaft is P, then P=2πn _o ×T(t)=2πn _i ×i(t)×T(t), namely $i\left(t\right)=\frac{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A2009100166430008H1.png"\; state="\{\{state\}\}">P</figure-callout>}}{{2\mathrm{\&pi;n}}_i\&times;T\left(t\right)}.$ The driving wheel connected with the input shaft adopts variable parameter cycloid gear, the driven wheel connected with the output shaft adopts the eccentric roller wheel which is in conjugate mesh with the driving wheel, and the rollers on the eccentric roller wheel adopt cylindrical or conical rolling bearings , Sliding bearings or pins. The rollers on the driven wheel are distributed with equal central angles. When the load is different, the distance from the center of the roller to the center of the output shaft is not equal. When the load increases, the load torque T(t) of the output shaft increases, the distance from the center of the roller to the center of the output shaft increases, and the corresponding speed of the output shaft n _o decreases, so the transmission ratio i(t) decreases small, according to the formula $i\left(t\right)=\frac{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A2009100166430008H1.png"\; state="\{\{state\}\}">P</figure-callout>}}{{2\mathrm{\&pi;n}}_i\&times;T\left(t\right)}$ It can be concluded that the power P of the output shaft remains unchanged; on the contrary, when the load decreases, the load torque T(t) of the output shaft decreases, the distance from the center of the roller to the center of the output shaft decreases, and the corresponding output shaft The rotational speed n _o increases, so the transmission ratio i(t) increases, according to the formula $i\left(t\right)=\frac{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A2009100166430008H1.png"\; state="\{\{state\}\}">P</figure-callout>}}{{2\mathrm{\&pi;n}}_i\&times;T\left(t\right)}$ It can be concluded that the power P of the output shaft remains unchanged. When the distance from the center of the roller to the center of the output shaft changes from large to small and from small to large, the outer contour of the driven wheel adopts a smooth curve transition.

Determine the contour shape of the driving wheel and the driven wheel through the following steps: (1) According to the change of load and according to the formula $i\left(t\right)=\frac{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A2009100166430008H1.png"\; state="\{\{state\}\}">P</figure-callout>}}{{2\mathrm{\&pi;n}}_i\&times;T\left(t\right)}$ Determine the transmission ratio i(t); (2) Determine the center distance between the input shaft and the output shaft according to the load and strength requirements; (3) Determine the center position of each roller on the roller wheel, the number of rollers, and the outer diameter of the rollers. (4) Solve the gear tooth shape of the drive wheel (variable parameter cycloid) according to the principle of conjugate meshing. According to the above method, the transmission of the driving wheel and the driven wheel meets the requirement of constant power.

The following two methods can be used to solve the tooth profile of the driving wheel:

Method 1. First, calculate the motion track curve of the roller center according to the motion relationship of conjugate meshing, x _oi = acosθ+r _di cos(θ _io +θ), y _oi =a sinθ+r _di sin(θ _io + θ), where a is the center distance between the input shaft and the output shaft, r _di is the distance from the center of the roller to the axis of the roller wheel, θ _io is the initial position angle of the roller, and θ is the point on the roller profile curve The angle between the line connecting the center of the cycloid gear and the x-axis; then, obtain the equidistant curve of the curve, which is the outer contour of the driving wheel and the driven wheel, and obtain the corresponding curve; finally, delete the part of the curve outside the meshing area and consider the strength to get rid of the tip angle of the tooth to get the shape of the gear tooth.

Method 2. First, calculate the curve corresponding to each roller based on the roller profile calculation formula derived from the principle of conjugate meshing and equidistant curve theory. The calculation formula is: $x_i=x_{\mathrm{oi}}-r_r\frac{{\mathrm{the\; y}}_{\mathrm{oi}}^{\&prime;}}{\sqrt{{x_{\mathrm{oi}}^{\&prime;}}^2+{{\mathrm{the\; y}}_{\mathrm{oi}}^{\&prime;}}^2}},$ ${\mathrm{the\; y}}_i={\mathrm{the\; y}}_{\mathrm{oi}}+r_r\frac{x_{\mathrm{oi}}^{\&prime;}}{\sqrt{{x_{\mathrm{oi}}^{\&prime;}}^2+{{\mathrm{the\; y}}_{\mathrm{oi}}^{\&prime;}}^2}},$ Among them, x _i and y _i are the coordinates of the roller profile curve, r _r is the radius of the roller, x _oi and y _oi are the coordinates of the center of the roller; and x _oi = a cosθ+r _di cos(θ _io +θ ), y _oi ＝xasinθ+r _di sin(θ _io +θ), where a is the center distance between the input shaft and the output shaft, r _di is the distance from the center of the roller to the axis of the roller wheel, and θ _io is the The initial position angle of the child, θ is the angle between the point on the roller profile curve and the line connecting the center of the cycloid gear and the x-axis; then, some curves outside the meshing area are deleted and the tooth tip angle is removed considering the strength, that is The shape of the gear tooth can be obtained.

The driving wheel connected to the input shaft can also use eccentric roller wheels. At this time, the driven wheel connected to the output shaft adopts a variable parameter cycloidal gear that is conjugated with the driving wheel. It can also be obtained according to the above principle: when the load changes , the power P of the output shaft remains unchanged.

The present invention is not limited to the above-mentioned specific implementation methods, and changes, modifications, additions or substitutions made by those skilled in the art within the essential scope of the present invention should also belong to the protection scope of the present invention. The technical features not described in the present invention can be realized by existing technologies, and will not be repeated here.

Claims (8)

1. the method for a permanent power transmission, it is characterized in that: the load torque of establishing on the transmission case output shaft is T (t), and input shaft rotational speed is n _i, the rotating speed of output shaft is n _o, velocity ratio is i (t), the power of output shaft is P, then P=2 π n _o* T (t)=2 π n _i* i (t) * T (t), promptly $i\left(t\right)=\frac{P}{2\mathrm{\&pi;}{n}_i\&times;T\left(t\right)},$ Load torque T (t) is during with load change, and velocity ratio i (t) changes thereupon, and power P is remained unchanged, and makes driving wheel that links to each other with described input shaft and the follower that links to each other with described output shaft adopt the variable element drive wheel of conjugation engagement according to above-mentioned formula.

2. the method for permanent power transmission according to claim 1 is characterized in that: the follower that links to each other with described output shaft is eccentric roller wheel, and the driving wheel that links to each other with input shaft adopts the variable element cycloidal gear with the engagement of follower conjugation.

3. the method for permanent power transmission according to claim 1 and 2 is characterized in that: the contour shape of described driving wheel and follower is poly-definite according to the following step: (1) is according to the variation of load and according to formula $i\left(t\right)=\frac{P}{2\mathrm{\&pi;}{n}_i\&times;T\left(t\right)}$ Determine velocity ratio i (t); (2) determine centre distance between input shaft, the output shaft according to load and requirement of strength; (3) determine roller wheel upward central position, roller quantity, the roller outer diameter of each roller; (4) find the solution the gear teeth shape of driving wheel according to the conjugation theory of engagement.

4. the method for permanent power transmission according to claim 3 is characterized in that: according to formula $x_i=x_{\mathrm{oi}}-r_r\frac{y_{\mathrm{oi}}^{\&prime;}}{\sqrt{x_{\mathrm{oi}}^{\&prime;2}+y_{\mathrm{oi}}^{\&prime;2}}},$ $y_i=y_{\mathrm{oi}}+r_r\frac{x_{\mathrm{oi}}^{\&prime;}}{\sqrt{x_{\mathrm{oi}}^{\&prime;2}+y_{\mathrm{oi}}^{\&prime;2}}}$ Calculate the centre coordinate of each roller, wherein, x _i, y _iBe the coordinate of roller contour curve, r _rBe radius of roller, x _Oi, y _OiCoordinate for roller centre; x _Oi=acos θ+r _DiCos (θ _Io+ θ), y _Oi=asin θ+r _DiSin (θ _Io+ θ), wherein, a is the centre distance between input shaft and the output shaft, r _DiBe the distance of roller centre to the roller wheel axis, θ _IoBe the roller initial position angle, θ is point on the roller contour curve and the angle between cycloidal gear circle center line connecting and the x axle.

5. the method for permanent power transmission according to claim 2 is characterized in that: each roller distributes for waiting central angle on the described follower.

6. the method for permanent power transmission according to claim 5 is characterized in that: the roller on the described follower adopts rolling bearing, sliding bearing or bearing pin.

7. the method for permanent power transmission according to claim 6 is characterized in that: described roller is cylindrical or conical.

8. the method for permanent power transmission according to claim 1 is characterized in that: the driving wheel that links to each other with described input shaft adopts eccentric roller wheel, and the follower that links to each other with output shaft is the variable element cycloidal gear that meshes with the driving wheel conjugation.

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