CN208686918U - A kind of spherical involute straight bevel gear pair - Google Patents

Abstract

The utility model discloses a kind of spherical involute straight bevel gear pair, including intermeshing driving gear and driven gear, the flank profil of gear is divided into two sections, and AB sections are theoretical spherical involute, and BD ' section is spherical surface modification curve, and B is correction of the flank shape starting point；Plane P is the generating surface of spherical involute, circular cone OO1A is spherical involute base cone, O is its vertex, establish global rectangular coordinate system S, wherein coordinate origin is basic circle conical point O, and vector OO1 direction is defined as z-axis, vector O1A direction is defined as x-axis, y-axis, described AB sections theoretical spherical involute are defined as according to the right-hand rule by z-axis and x-axis direction.The utility model driving gear and driven gear profile modification are simultaneously by the way of tooth top tip relief；Modification curve is one section of curve where spherical involute on spherical surface, can be reduced gear it is engaging-in, nibble out and impact, reduce vibration and noise, improve the quality and service life of gear pair.

Description

A kind of spherical involute straight bevel gear pair

Technical field

The utility model relates to design of gears and manufacturing technology field, and in particular to a kind of spherical involute straight bevel gear It is secondary.

Background technique

Transmission ratio variation when gear engages is considered as one of the source of gear vibration and noise, to guarantee constant biography Dynamic ratio, straight bevel gear pair tooth curve should be spherical involute；But due to not deep to spherical involute drive characteristic understanding, Straight bevel gear is typically all that back cone involute is used to model, although back cone involute is very close with spherical involute and models It is convenient, but there is always errors for the modeling method, and when the ratio between spherical radius and module are smaller, error is bigger；Car is poor The spherical radius and module ratio of fast device straight bevel gear are smaller, and tooth profile error is just very big, thus bring transmission ratio Vibration and noise will be apparent caused by variation；Currently, although differential mechanism spherical involute straight bevel gear batch forges still Be not implemented, but spherical involute Straight Bevel Gear Drive relative to the advantages of plane involute Straight Bevel Gear Drive make its at The hot spot developed for present colleges and business research；

Due to loading the presence of flexible deformation, gear pair is engaging-in and when nibbling out, and the base pitch of planet and semiaxis is unequal, i.e., It generates engaging-in and nibbles out and interfere, thus bring vibration and the noise of gear pair, repaired about spherical involute straight bevel gear flank profil Shape has had some researchs, and the common ground of these researchs is that theoretical spherical involute is drawn in three-dimensional software, correction of the flank shape part It being replaced with plane curves such as straight line parabolas, advantage is visual pattern, it is easily designed, the disadvantage is that profiling quantity and correction of the flank shape direction cannot Accurately reflect the deformation direction and size of flexible deformation, it is understood that there may be the problem of excessive correction of the flank shape or correction of the flank shape deficiency.

Utility model content

The utility model is above-mentioned in order to overcome the shortcomings of, provide it is a kind of reduce gear it is engaging-in, nibble out and impact, reduce vibration And noise, improve the meshing quality of gear and the spherical involute straight bevel gear pair of service life.

The utility model achieves the above object through the following technical schemes:

A kind of spherical involute straight bevel gear pair, including driving gear and the driven gear engaged with driving gear, institute The flank profil for stating gear is divided into two sections, and AB sections are theoretical spherical involute, and BD ' section is spherical surface modification curve, and B is correction of the flank shape starting point.

Plane P is the generating surface of spherical involute, and circular cone OO1A is spherical involute base cone, and O is its vertex, is established complete Office rectangular coordinate system S, wherein coordinate origin is basic circle conical point O, vector OO1 direction is defined as z-axis, by vector O1A Direction is defined as x-axis, is defined as y-axis according to the right-hand rule by z-axis and x-axis direction, described AB sections theoretical spherical involute, Its equation are as follows:

Wherein, R is the sphere diameter for engaging spherical surface, and θ is cone generating angle,It is on the field of conjugate action between initial segment and instantaneous rotating shaft Angle；

BD ' the section is spherical surface modification curve, equation are as follows:

Wherein, R is the sphere diameter for engaging spherical surface, and θ is cone generating angle,It is on the field of conjugate action between initial segment and instantaneous rotating shaft Angle, Δ s be each correction of the flank shape point profiling quantity of standard spherical involute.

The beneficial effects of the utility model are: compared with the existing technology, the utility model spherical involute straight bevel gear The profile modification of pair, driven gear and driving gear is simultaneously by the way of tooth top tip relief；Modification curve is spherical involute institute One section of curve on spherical surface, correction of the flank shape direction are that spherical surface gradually opens normal direction, and correction of the flank shape starting point and profiling quantity can be according to limited Meta algorithm optimizes to obtain, can be reduced gear it is engaging-in, nibble out and impact, reduce vibration and noise, improve the meshing quality of gear pair And service life.

Detailed description of the invention

The utility model will illustrate by example and with reference to the appended drawing, in which:

Fig. 1 is the structural schematic diagram of the utility model；

Fig. 2 is the driving gear big end spherical involute tooth top tip relief schematic diagram of the utility model；

Fig. 3 is the driven gear big end spherical involute tooth top tip relief schematic diagram of the utility model.

In figure: 1. driving gears, 2. driven gears.

Specific embodiment

The utility model is described in further detail presently in connection with attached drawing.These attached drawings are simplified schematic diagram, Only illustrate the basic structure of the utility model in a schematic way, therefore it only shows composition related with the utility model.

A kind of spherical involute straight bevel gear pair as shown in Figure 1: is engaged including driving gear 1 and with driving gear 1 Driven gear 2, flank profil is divided into two sections after the profile modification of the gear, and AB sections are theoretical spherical involute, and BD ' section is repaired for spherical surface Shape curve, B are correction of the flank shape starting point.

Plane P is the generating surface of spherical involute, and circular cone OO1A is spherical involute base cone, and O is its vertex, is established complete Office rectangular coordinate system S, wherein coordinate origin is basic circle conical point O, vector OO1 direction is defined as z-axis, by vector O1A Direction is defined as x-axis, is defined as y-axis, the AB sections of spherical involute, side according to the right-hand rule by z-axis and x-axis direction Journey are as follows:

Wherein, R is the sphere diameter for engaging spherical surface, and θ is cone generating angle,It is on the field of conjugate action between initial segment and instantaneous rotating shaft Angle.

BD ' the section is correction of the flank shape spherical curve, equation are as follows:

Wherein, R is the sphere diameter for engaging spherical surface, and θ is cone generating angle,It is on the field of conjugate action between initial segment and instantaneous rotating shaft Angle, Δ s is theoretical each correction of the flank shape point profiling quantity of spherical involute.

A kind of profile modification method of spherical involute straight bevel gear pair: the following steps are included:

Software moulding → manufacture correction of the flank shape mold → batch production；

In software step of overall modelling, driven gear 2 and 1 profile modification of driving gear are simultaneously by the way of tooth top tip relief； Modification curve is one section of curve where spherical involute on spherical surface, and correction of the flank shape direction is that spherical surface gradually opens normal direction, correction of the flank shape starting Point and profiling quantity can optimize to obtain according to finite element algorithm；

Wherein, the spherical involute straight bevel gear step of overall modelling of profile modification are as follows:

Step 1: the big end of driving gear 1 and driven gear 2 and the theoretical spherical involute of small end are asked；

Step 2: establishing the 2 engaging tooth wheel set of driving gear 1 and driven gear of non-correction of the flank shape, carries out Finite Element Simulation Analysis；

Step 3: on driving gear 1 and 2 big end of driven gear and small end spherical involute from tooth top to tooth root direction The point of one total displacement < 0.05 is correction of the flank shape starting point, records the respective total displacement amount of each point on spherical involute, big according to gear The quantity of small selected element；

Step 4: each point coordinate on modification curve is calculated；

Step 5: by above-mentioned steps one and big end obtained in step 4 and small end spherical involute and its modification curve number Strong point imports 3D modeling software, and " passing through curve group " order directly generates side tooth in 3D modeling software curved surface modeling module Dough sheet body；

Step 6: it is ordered using " mirror image features " in 3D modeling software solid modelling module, the tooth that will be generated in step 5 Face mirror image establishes the symmetrical flank of tooth；

Step 7: by the symmetrical flank of tooth in two sides, model is established according to straight bevel gear routine modeling procedure；

In manufacture correction of the flank shape molding process, mold of practicing Buddhism or Taoism is manufactured using numerically-controlled machine tool.

The numerically-controlled machine tool is high speed milling machine tool；In batch production step, using forging technology, extensive batch is realized Metaplasia produces；The 3D modeling software is UG.

Embodiment 1:

As shown in Figure 2: AD sections are theoretical spherical involute, and plane P is the generating surface of spherical involute, and circular cone OO1A is ball Face involute base cone, O are its vertex, and B is correction of the flank shape starting point, and flank profil is divided into two sections after correction of the flank shape, and AB sections are gradually opened for theoretical spherical surface Line, BD ' section are spherical surface modification curve；

Global rectangular coordinate system S is established, wherein coordinate origin is basic circle conical point O, and vector OO1 direction is defined as Vector O1A direction is defined as x-axis by z-axis, is defined as y-axis, spherical involute according to the right-hand rule by z-axis and x-axis direction It is derived as common knowledge, the application no longer does specific derivation, directly gives conclusion:

AB sections of spherical involutes, equation are as follows:

Wherein, R is the sphere diameter for engaging spherical surface, and θ is cone generating angle,It is on the field of conjugate action between initial segment and instantaneous rotating shaft Angle；

BD ' section is correction of the flank shape spherical curve, equation are as follows:

Wherein, R is the sphere diameter for engaging spherical surface, and θ is cone generating angle,It is on the field of conjugate action between initial segment and instantaneous rotating shaft Angle, Δ s is theoretical each correction of the flank shape point profiling quantity of spherical involute；

Without loss of generality, by taking C point in arbitrary point in spherical involute BD section as an example, C point coordinate is obtained by following step C′；

Obtaining C point homogeneous coordinates by spherical involute formula is

1, local coordinate system S is established in C point_c, coordinate origin C, change in coordinate axis direction is by step determination:

A, spherical involute derived function is sought, equation is

B, C point coordinate is substituted into above-mentioned derived function equation and obtains spherical involute in the tangent vector τ of C point

C, above-mentioned C point tangent vector is unitization and be defined as local coordinate system S_cX_CIt is axial

D, C point and is defined into local coordinate system S at unitization to diameter under global coordinate system_cY_CIt is axial:

F, it seeks the vector product of above-mentioned two steps unit vector and is defined as local coordinate system S_cZ_CIt is axial:

2, C ' S under local coordinate system are sought_cUnder coordinate:

(2Rsin(Δs/2R)cos(Δs/R),-2Rsin(Δs/2R)sin(Δs/R),0)

Δ s is each correction of the flank shape point profiling quantity of theoretical spherical involute；

For convenient data processing, this coordinate is rewritten into homogeneous coordinates form

3, it asks by local coordinate system S_cTransform to the transformation matrix of global coordinate system S:

Wherein, (1,0,0) i=；J=(0,1,0)；I=(0,0,1) is respectively the x-axis, y-axis, z-axis axis of global coordinate system S To unit vector；

4, C ' homogeneous coordinates at world coordinates S are sought:

C ' coordinates under global coordinate system are unfolded to obtain in above formula:

D point is the end of spherical involute correction of the flank shape section BD, and C is any point thereon, then point coordinate is therewith after the practicing Buddhism or Taoism of D point It is identical；Similarly, point coordinate is identical with C ' coordinates after D ' practice Buddhism or Taoism.

Wherein, the profiling quantity in the position of correction of the flank shape starting point B and BD section at each correction of the flank shape point optimizes according to finite element method and counts It obtains, target is that engaging-in interference does not occur for engaged transmission and nibbles out to interfere under nominal torque.

Embodiment 2:

As shown in Figure 3, it is contemplated that bevel gear small end modulus and tooth height are smaller, and spherical involute needs the portion of correction of the flank shape herein Divide BC arc length often no more than 0.1, method as described in Figure 3, which has been calculated, all can reach same technique effect, and can simplify calculating and mention High working efficiency is reduced proper motion, only calculates tooth top according to method in specific embodiment 1 to theoretical spherical involute tooth end C Coordinate points C ' after correction of the flank shape, modification curve BC ' are the connection tooth top correction of the flank shape point C ' on the spherical surface of sphere where spherical involute With one section of great circle minor arc of correction of the flank shape starting point B；Its equation is easy to get, and three-dimensional modeling is also extremely convenient；In figure, AC sections are theory Spherical involute, plane P are the generating surface of spherical involute, and circular cone OO1A is spherical involute base cone, and O is its vertex, and B is Correction of the flank shape starting point, C are standard spherical involute teeth vertex, and C ' is tooth top correction of the flank shape point, and flank profil is divided into two sections after correction of the flank shape, AB Duan Weili By spherical involute, BC ' is the great circle minor arc where spherical involute on spherical surface.

Taken in this application be directed to spherical surface gradually for technical problem caused by the conventional profile modification scheme of solution The tooth top tip relief technical solution that bursts at the seams is applicable not only to differential side gear 2 and driving gear 1, is also applied for other gear drives The middle transmission device using spherical involute straight bevel gear.

Above-mentioned foundation the utility model is enlightenment, and through the above description, relevant staff completely can be not In the range of deviateing this item utility model technical idea, various changes and amendments are carried out.This item utility model it is technical Range is not limited to the contents of the specification, it is necessary to which the technical scope thereof is determined according to the scope of the claim.

Claims (1)

1. a kind of spherical involute straight bevel gear pair, special including driving gear and the driven gear engaged with driving gear Sign is: the flank profil of the gear is divided into two sections, and AB sections are theoretical spherical involute, and BD ' section is spherical surface modification curve, and B is to repair Shape starting point；

Plane P is the generating surface of spherical involute, and circular cone OO1A is spherical involute base cone, and O is its vertex, is established global straight Angular coordinate system S, wherein coordinate origin is basic circle conical point O, and vector OO1 direction is defined as z-axis, will be where vector O1A Direction definition is x-axis, is defined as y-axis, described AB sections theoretical spherical involute, side according to the right-hand rule by z-axis and x-axis direction Journey are as follows:

Wherein, R is the sphere diameter for engaging spherical surface, and θ is cone generating angle,It is the folder on the field of conjugate action between initial segment and instantaneous rotating shaft Angle；

BD ' the section is spherical surface modification curve, equation are as follows:

Wherein, R is the sphere diameter for engaging spherical surface, and θ is cone generating angle,It is the folder on the field of conjugate action between initial segment and instantaneous rotating shaft Angle, Δ s are each correction of the flank shape point profiling quantity of theoretical spherical involute.