阅读说明：本技术 一种斜撑离合器结构的正向设计与计算方法 (Forward design and calculation method of inclined strut clutch structure ) 是由 卢敏 陈志豪 靳国栋 李继峰 李政民卿 于 2020-06-04 设计创作，主要内容包括：本发明公开了一种斜撑离合器结构的正向设计与计算方法,正向设计包括包括呈圆弧型面设置的楔块、外套和内轴,所述外套和内轴之间形成滚道,所述楔块可滑动设于滚道内；计算方法包括S1反转内外滚道、并对楔块的运动进行分析以及S2求解最大升程。本发明属于斜撑式超越离合器的设计方法技术领域,具体是提供了一种在不改变基本参数的前提下,对楔块结构进行局部修正并增设新的参数,使四种标准楔块的有效升程,全部大于对应的原标准数据并达到最大值,进而提高了离合器整体的翻转力矩和极限载荷,使包括强制连续型斜撑离合器和全相位型斜撑离合器在内的两种形式的斜撑式超越离合器整体性能得以提升的斜撑离合器结构的正向设计与计算方法。(The invention discloses a forward design and calculation method of a diagonal bracing clutch structure, wherein the forward design comprises a wedge block, an outer sleeve and an inner shaft which are arranged in an arc-shaped surface, a raceway is formed between the outer sleeve and the inner shaft, and the wedge block is arranged in the raceway in a sliding manner; the calculation method comprises the steps of S1 reversing the inner and outer raceways, analyzing the motion of the wedge block and S2 solving for the maximum lift. The invention belongs to the technical field of design methods of a diagonal bracing type overrunning clutch, and particularly provides a forward design and calculation method of a diagonal bracing type overrunning clutch structure, which is characterized in that on the premise of not changing basic parameters, the wedge block structure is locally corrected, new parameters are added, the effective lift ranges of four standard wedge blocks are all larger than the corresponding original standard data and reach the maximum value, the overall overturning moment and the ultimate load of the clutch are further improved, and the overall performance of two types of diagonal bracing type overrunning clutches including a forced continuous type diagonal bracing clutch and a full-phase type diagonal bracing clutch is improved.)

1. A forward design of sprag clutch structure characterized in that: the wedge block is arranged in the raceway in a sliding mode, and an upper cambered surface and a lower cambered surface, which are in contact with the raceway, of the wedge block are composed of two eccentric arcs.

2. A method of calculating a sprag clutch configuration, comprising the steps of:

s1, reversing the inner raceway and the outer raceway and analyzing the motion of a wedge block:

assuming that the wedge block is still, the wedge block comprises an inner arc, an outer arc and a side line, in an initial state, points Q and C are wedging points of the inner arc and the inner raceway of the wedge block and wedging points of the outer arc and the outer raceway of the wedge block respectively, the central point of a circle where the inner raceway is located is set to be O, the width of the wedge block is b, and the radius r of the inner arc is r_iOuter arc radius r₀The center distance Z and the center angle α are 5 basic parameters of a clutch wedge block with standard specification, J₀Is a specification parameter of the wedge, and R₀、R_iSetting parameters for the radius of the inner shaft and the outer sleeve of the clutch and the distance t from the center of the inner arc to the corresponding edge of the wedge block

along with the application of torque load of an engine, wedging transmission of the wedge block is started from a point Q and a point C, the wedge block is gradually overturned between the inner raceway and the outer raceway to the maximum lift, and points of the wedge block, which are respectively contacted with the outer raceway and the inner raceway, are changed into boundary points C 'and Q' until overturning failure;

the initial wedging height of the wedge block between the inner raceway and the outer raceway is H_nomAnd the maximum height of the wedge block which is turned in the roller path is recorded as H_maxAnd the difference value between the maximum height reached by the wedge block in the overturning process and the initial wedging height is the lift of the wedge block, and the lift relation is shown as an formula I:

S_R＝H_max-H_nomi formula

In the formula, S_RRepresenting the lift distance of the wedge;

for a wedge structure with a given width, when boundary points Q ' and C ' of an outer arc and an inner arc are simultaneously limit points of the wedge lift, the maximum lift of the wedge is obtained, a reverse method of a cam design is imitated, at the moment, an inner shaft and an outer sleeve rotate around a point A of the outer arc center point of the wedge in a reverse direction, at the moment, the center rotates to a position O ' from O, at the moment, the wedge is used as a cam rigid body, the inner shaft is pushed and extruded as a driven member, and the radius of the deformed inner shaft is set as R_i′，The included angle of the connecting line of the centers of circles before and after rotation is shown, and the point B is the central point of the circle where the inner circular arc of the wedge block is located;

s2, solving the maximum lift:

first, Δ QOC has the relationship shown in formula ii:

wherein the content of the first and second substances,q, C is the distance between two points;

second, at Δ Q' BD_iWherein the relation is shown as formula III:

∠ ABO '═ pi- ∠ Q' BD can be obtained from the above_i-α；

Again, in Δ O' AB there is a relationship as shown in formula IV:

wherein the content of the first and second substances,

then, there is also a relation ∠ D₀C′A＝π/2-(∠BAO′-α)，

And there exists a relational expression

let t be an increasing variable, corresponding to formula III-IV

when b' is b, the position at the limit of the wedge lift is obtainedR_i' and margin

At this time, the product can be obtainedThe relation is shown as VI:

finally, according to the formula I, the maximum lift value of the wedge block with optimized structure can be obtained, namely

Obviously, S_RThe resulting effective maximum lift of the wedge is calculated according to the reverse method.

Technical Field

The invention belongs to the technical field of design methods of an inclined strut type overrunning clutch, and particularly relates to a forward design and calculation method of an inclined strut clutch structure.

Background

The sprag-type overrunning clutch includes a forced continuous sprag clutch and a full-phase sprag clutch, both of which belong to friction-type overrunning clutches. An overrunning clutch is a clutch that can be automatically engaged or disengaged according to the change of relative movement speed of a driving part and a driven part or the change of a rotating direction. The inclined strut clutch has the characteristics of large transmission torque and small mass, and is widely applied to working environments such as helicopter transmission systems, starters of aircraft engines, automatic transmission automobile gearboxes and the like.

Early literature is the main reference basis of the circular arc type surface clutch at home and abroad, but specific positions are not given to the width of a wedge block, and the embedded design method and basis are not given. In later studies, the main focus was on comparative analysis of properties and structural design of profiles. However, the circular arc type surface clutch is still the main product structure form of related research institute and enterprises to date. Therefore, the construction details of the inclined strut clutch need to be deepened, relevant basic research and optimization upgrading are well done, and theoretical and technical support is provided for the forward design of the follow-up clutch.

Disclosure of Invention

In order to solve the existing problems, the invention provides a common reversal method in cam profile curve design, aiming at the inclined strut type overrunning clutch with two forms of a forced continuous inclined strut clutch and a full-phase inclined strut clutch, under the premise of not changing basic parameters, the wedge block structure is locally corrected, new parameters are added, the effective lift of four standard wedge blocks is enabled to be completely larger than the corresponding original standard data and reach the maximum value, the integral overturning moment and the ultimate load of the clutch are further improved, and the integral performance of the clutch is improved.

The technical scheme adopted by the invention is as follows: a forward design of a diagonal bracing clutch structure comprises a wedge block, an outer sleeve and an inner shaft which are arranged in an arc-shaped surface, wherein a roller path is formed between the outer sleeve and the inner shaft, the wedge block is slidably arranged in the roller path, and the upper arc surface and the lower arc surface of the wedge block, which are in contact with the roller path, are composed of two eccentric arcs.

A method of calculating a sprag clutch configuration, comprising the steps of:

s1, reversing the inner raceway and the outer raceway and analyzing the motion of a wedge block:

assuming that the wedge block is still, the wedge block comprises an inner arc, an outer arc and a side line, in an initial state, points Q and C are wedging points of the inner arc and the inner raceway of the wedge block and wedging points of the outer arc and the outer raceway of the wedge block respectively, the central point of a circle where the inner raceway is located is set to be O, the width of the wedge block is b, and the radius r of the inner arc is r_iOuter arc radius r₀The center distance Z and the center angle α are 5 basic parameters of a clutch wedge block with standard specification, J₀Is a specification parameter of the wedge, and R₀、R_iSetting parameters for the radius of the inner shaft and the outer sleeve of the clutch and the distance t from the center of the inner arc to the corresponding edge of the wedge block

Is the vertical distance from the center of the outer circular arc of the wedge block to the side line, D_i、D₀The vertical foot points from the centers of the inner arc and the outer arc of the wedge block to the side line are respectively;

along with the application of torque load of an engine, wedging transmission of the wedge block is started from a point Q and a point C, the wedge block is gradually overturned between the inner raceway and the outer raceway to the maximum lift, and points of the wedge block, which are respectively contacted with the outer raceway and the inner raceway, are changed into boundary points C 'and Q' until overturning failure;

the initial wedging height of the wedge block between the inner raceway and the outer raceway is H_nomAnd the maximum height of the wedge block which is turned in the roller path is recorded as H_maxAnd the difference value between the maximum height reached by the wedge block in the overturning process and the initial wedging height is the lift of the wedge block, and the lift relation is shown as an formula I:

S_R＝H_max-H_nomi formula

In the formula, S_RRepresenting the lift distance of the wedge;

for theThe wedge structure with given width can obtain maximum lift when the boundary points Q ' and C ' of the outer arc and the inner arc are simultaneously limit points of the lift of the wedge, the inner shaft and the outer sleeve rotate reversely around the central point A of the outer arc of the wedge according to the reverse method of the cam design, the center rotates to the position O ' from O, the wedge is used as a cam rigid body, the inner shaft is pushed and extruded as a driven member, and the radius of the deformed inner shaft is set as R_i′，The included angle of the connecting line of the centers of circles before and after rotation is shown, and the point B is the central point of the circle where the inner circular arc of the wedge block is located; the reverse rotation method for designing the cam is based on the basic principle that the cam is relatively static, the ejector rod rotates around the center of the cam at an equal angular speed, and the movement track of the peak is the contour curve of the cam because the peak of the ejector rod is always in contact with the contour curve of the cam. The wedge block and the cam are both of eccentric rotating structures, and have edge contact action with adjacent structural parts all the time in the motion process. Therefore, the related theory and method of the cam can be used for reference in the forward design and research including the sprag overrunning clutches of the two forms of the forced continuous sprag clutch and the full phase sprag clutch.

S2, solving the maximum lift:

first, Δ QOC has the relationship shown in formula ii:

wherein the content of the first and second substances,q, C is the distance between two points;

second, at Δ Q' BD_iWherein the relation is shown as formula III:

thus, can obtain∠ABO′＝π-∠Q′BD_i-α；

Again, in Δ O' AB there is a relationship as shown in formula IV:

wherein the content of the first and second substances,

then, there is also a relation ∠ D₀C′A＝π/2-(∠BAO′-α)，

And there exists a relational expressionThe obtained relation is shown as the formula V:

let t be an increasing variable, corresponding to formula III-IV

And b';

when b' is b, the position at the limit of the wedge lift is obtainedR_i' and margin

At this time, the product can be obtained

The relation is shown as VI:

finally, according to the formula I, the maximum lift value of the wedge block with optimized structure can be obtained, namely

Obviously, S_RThe resulting effective maximum lift of the wedge is calculated according to the reverse method.

The beneficial effects obtained by the invention by adopting the structure and the calculation method are as follows: the scheme is that a forward design and calculation method of an inclined strut clutch structure simulates a common reversal method in cam profile curve design to carry out lift optimization and calculation of a wedge block, according to the calculation result, the structural positioning of the wedge block in the width direction is corrected, so that the arc lengths of the upper arc surface and the lower arc surface of the wedge block are reasonably distributed, the effective lift value of the wedge block is further optimized, on the premise of not changing 5 basic parameters of the wedge block, the four standard wedge blocks are all optimized in width position by the method to obtain a new wedge block lift optimized value which is listed in a common standard value table, the effective lift of the four standard wedges is completely optimized, the calculation result is obviously increased, the overturning moment of the clutch is improved, the probability of wedge overturning failure is reduced, and the overall performance of the sprag type overrunning clutch comprising a forced continuous sprag clutch and a full-phase sprag clutch is improved.

Drawings

FIG. 1 is a schematic diagram of the wedge lift for a forward design and calculation method of a sprag clutch configuration according to the present invention;

FIG. 2 is a diagram of the reverse rotation inner and outer races of a forward design and calculation method of a sprag clutch structure of the present invention;

fig. 3 is a schematic structural diagram of a forward design and calculation method of a sprag clutch structure according to the present invention.

Wherein, 1, an outer sleeve, 2, a wedge block, 3 and an inner shaft.

Fig. 1a is a schematic view showing an initial wedging state of the wedge with the outer sleeve and the inner shaft, and fig. 1b is a schematic view showing a critical overturning state of the wedge with the outer sleeve and the inner shaft.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments; all other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1-3, the forward design of the sprag clutch structure of the invention comprises a wedge 2, an outer sleeve 1 and an inner shaft 3 which are arranged in an arc-shaped surface, a raceway is formed between the outer sleeve 1 and the inner shaft 3, the wedge 2 is slidably arranged in the raceway, and the upper and lower arc surfaces of the wedge 2, which are in contact with the raceway, are composed of two eccentric arcs.

A method of calculating a sprag clutch configuration, comprising the steps of:

s1, reversing the inner raceway and the outer raceway and analyzing the motion of a wedge block:

assuming that the wedge block is still, wherein the wedge block comprises an inner arc, an outer arc and a side line, in an initial state, points Q and C are wedging points of the inner arc and the inner raceway of the wedge block and wedging points of the outer arc and the outer raceway of the wedge block respectively, and at the moment, the central point of a circle where the inner raceway is located is set as O; as shown in FIG. 2, the wedge has a width b and an inner arc radius r_iOuter arc radius r₀The center distance Z and the center angle α are 5 basic parameters of a clutch wedge block with standard specification, J₀Is a specification parameter of the wedge, and R₀、R_iSetting parameters for the radius of the inner shaft and the outer sleeve of the clutch and the distance t from the center of the inner arc to the corresponding edge of the wedge blockIs the vertical distance from the center of the outer circular arc of the wedge block to the side line, D_i、D₀The vertical foot points from the centers of the inner arc and the outer arc of the wedge block to the side line are respectively;

as shown in fig. 1a and 1b, the wedge block starts to wedge into transmission from a point Q and a point C along with the application of the torque load of the engine, the wedge block is gradually overturned between the inner raceway and the outer raceway to the maximum lift, and the contact points of the wedge block with the outer raceway and the inner raceway are changed into boundary points of C 'and Q' until overturning failure;

the initial wedging height of the wedge block between the inner raceway and the outer raceway is H_nomAnd the maximum height of the wedge block which is turned in the roller path is recorded as H_maxThe difference between the maximum height reached by the wedge block in the overturning process and the initial wedging height is the lift of the wedge block, the dotted line in fig. 1 is the initial position of the inner and outer raceways before deformation, and the lift relation is shown as formula I:

S_R＝H_max-H_nomi formula

In the formula, S_RRepresenting the lift distance of the wedge;

for a wedge structure with a given width, when boundary points Q ' and C ' of an outer arc and an inner arc are simultaneously limit points of the wedge lift, the maximum lift of the wedge is obtained, a reverse method of a cam design is imitated, at the moment, an inner shaft and an outer sleeve rotate around a point A of the outer arc center point of the wedge in a reverse direction, at the moment, the center rotates to a position O ' from O, at the moment, the wedge is used as a cam rigid body, the inner shaft is pushed and extruded as a driven member, and the radius of the deformed inner shaft is set as R_i′，

The included angle of the connecting line of the centers of circles before and after rotation is shown, and the point B is the central point of the circle where the inner circular arc of the wedge block is located; as shown in fig. 1b, the broken lines show the arc of the outer casing and the arc of the inner shaft of the wedge after rotation;

s2, solving the maximum lift:

first, Δ QOC has the relationship shown in formula ii:

wherein the content of the first and second substances,q, C is the distance between two points;

second, at Δ Q' BD_iWherein the relation is shown as formula III:

∠ ABO '═ pi- ∠ Q' BD can be obtained from the above_i-α；

Again, in Δ O' AB there is a relationship as shown in formula IV:

wherein the content of the first and second substances,

then, there is also a relation ∠ D₀C′A＝π/2-(∠BAO′-α)，

And there exists a relational expressionThe obtained relation is shown as the formula V:

let t be an increasing variable, corresponding to formula III-IVAnd b';

when b' is b, the position at the limit of the wedge lift is obtainedR_i' and margin

At this time, the product can be obtainedThe relation is shown as VI:

finally, according to the formula I, the maximum lift value of the wedge block with optimized structure can be obtained, namely

Obviously, S_RCalculating the effective maximum lift of the wedge according to a reverse method;

on the premise of not changing 5 basic parameters of the wedge block, the width and the position of the four standard wedge blocks are all optimized by the method to obtain a new wedge block lift optimized value, and the new wedge block lift optimized value is listed in a common standard value table, and is shown in the following table 1;

TABLE 1 Lift comparison before and after Standard wedge optimization

It can be seen that the effective lifts of the four standard wedges are all optimized and the calculation results show an average growth rate of 30.675%.