CN203335734U - Asymmetric involute worm and helical gear pair - Google Patents

Abstract

The utility model discloses an asymmetric involute worm and helical gear pair. The asymmetric involute worm and helical gear pair comprises a worm and a helical gear, wherein a worm meshing side tooth profile and a worm non-meshing side tooth profile are arranged on the two sides of each gear tooth of the worm respectively, a helical gear meshing side tooth profile and a helical gear non-meshing side tooth profile are arranged on the two sides of each gear tooth of the helical gear respectively, the axial module of the worm is m1, the transverse module of the helical gear is m2, the pressure angle of each worm meshing side tooth profile is alpha1, the pressure angle of each worm non-meshing side tooth profile is alpha2, the pressure angle of each helical gear meshing side tooth profile is alpha3, the pressure angle of each helical gear non-meshing side tooth profile is alpha4, the addendum coefficient of each worm meshing side tooth profile is , the addendum coefficient of each worm non-meshing side tooth profile is , the tip clearance coefficient of each worm meshing side tooth profile is , and the tip clearance coefficient of each worm non-meshing side tooth profile is . When the included angle sigma between the axis of the worm and the axis of the helical gear is 90 degrees, in order to ensure correct meshing between the worm and the helical gear, the following conditions that the alpha1 is larger than the alpha2, and the alpha3 is larger than the alpha4; when the m1 is equal to the m2, the alpha1 is equal to the alpha3, and the alpha2 is equal to the alpha4; when the m1 is not equal to the m2, m1*cosalpha1=m2*cosalpha3, m1*cosalpha2=m2*cosalpha4 and the like need to be met.

Description

A kind of asymmetric involute worm helical gear pair

Technical field

The utility model relates to a kind of asymmetric involute worm helical gear pair, belongs to helical gear worm screw mechanical transmissioning technology field.

Background technique

At present, because having, velocity ratio is large in worm drive, stable drive, vibration are little, low noise advantages, and is widely used.The quality of worm drive performance and quality thereof has influence on the quality height of engineening goods the most at last, therefore, in order to meet the needs of the large production of modernization, requires the transmission performance of worm screw to continue to optimize.In recent years, in each side such as the mesh theory of worm and helical gear, bearing capacity calculating, novel worm drive, very large development is all arranged.In the worm drive process, the shape of the gear teeth not only can have influence on worm geared kinetic characteristic, but also can have influence on the power performance of worm and helical gear transmission.In order to adapt to the development trend of the large production of modernization, people constantly probe into the tooth profile profile of tooth, and asymmetric involute worm spiral gear drive mechanism produces under this historical background.Under prior art, when in transmission during than large bearing capacity, helical gear tooth root easily fractures.

The model utility content

Technical problem to be solved in the utility model is the defect that overcomes prior art, and a kind of asymmetric involute worm helical gear pair is provided, and it can effectively avoid helical gear tooth root fracture, the shock resistance while improving its transmission and bearing capacity.

The utility model solves the problems of the technologies described above the technological scheme of taking: a kind of asymmetric involute worm helical gear pair, comprise worm screw and helical gear, the gear teeth both sides of worm screw have respectively worm meshing side flank profil and the non-engagement side flank profil of worm screw, helical gear gear teeth both sides have respectively helical gear engagement side flank profil and the non-engagement side flank profil of helical gear, wherein, the axial module of worm screw is m ₁, helical gear transverse module is m ₂, the pressure angle of worm meshing side flank profil is α ₁, the pressure angle of the non-engagement side flank profil of worm screw is α ₂, the pressure angle of helical gear engagement side flank profil is α ₃, the pressure angle of the non-engagement side flank profil of helical gear is α ₄, the addendum coefficient of worm meshing side flank profil is

the addendum coefficient of the non-engagement side flank profil of worm screw is the tip clearance coefficient of worm meshing side flank profil is

the tip clearance coefficient of the non-engagement side flank profil of worm screw is in the situation that worm screw, helical gear diaxon angle Σ=90 °, in order to guarantee worm and helical gear energy correct engagement, meet following four conditions:

a、α ₁＞α ₂，α ₃＞α ₄；

B, work as m ₁=m ₂the time, α ₁=α ₃, α ₂=α ₄; Work as m ₁≠ m ₂the time, m ₁cos α ₁=m ₂cos α ₃, m ₁cos α ₂=m ₂cos α ₄;

c、 $h_{\mathrm{ad}}^{*}=h_{\mathrm{ac}}^{*}+c_c^{*}-(1-\sin {\mathrm{\&alpha;}}_1)\frac{\frac{\mathrm{\&pi;}{\mathrm{<figure-callout\; id="1"\; label="m"\; filenames="HDA00003443569100011.png"\; state="\{\{state\}\}">m</figure-callout>}}_1}{2}-(\tan {\mathrm{\&alpha;}}_2+\tan {\mathrm{\&alpha;}}_1)(h_{\mathrm{ac}}^{*}{\mathrm{<figure-callout\; id="1"\; label="m"\; filenames="HDA00003443569100011.png"\; state="\{\{state\}\}">m</figure-callout>}}_1+c_c^{*}{m}_1)}{\sec {\mathrm{\&alpha;}}_2+\sec {\mathrm{\&alpha;}}_1-\tan {\mathrm{\&alpha;}}_2-\tan {\mathrm{\&alpha;}}_1};$

d、 $c_d^{*}=(1-\sin {\mathrm{\&alpha;}}_1)\frac{\frac{\mathrm{\&pi;}}{2}-(\tan {\mathrm{\&alpha;}}_2+\tan {\mathrm{\&alpha;}}_1)(h_{\mathrm{ac}}^{*}+c_c^{*})}{\sec {\mathrm{\&alpha;}}_2+\sec {\mathrm{\&alpha;}}_1-\tan {\mathrm{\&alpha;}}_2-\tan {\mathrm{\&alpha;}}_1}.$

Further, described worm screw is made of metal.

Further, described helical gear is made by metal or plastics.

After having adopted technique scheme, in the design of worm and helical gear, increase pressure angle and can improve the tooth root bending fatigue strength, thereby improve its bearing capacity, for the symmetrical involute worm spiral gear drive mechanism of routine, if increase the pressure angle of gear teeth both sides simultaneously, will cause the attenuation of helical gear tooth top, the possibility that adds the large helical gear broken teeth, the shock resistance that is the helical gear gear teeth will descend, in worm and helical gear pair of the present utility model, when worm drive, the stressing conditions of considering the working surface of the gear teeth and non-working surface is different, the working flank of the gear teeth is that the pressure angle of engagement side flank profil is that the pressure angle of non-engagement side flank profil is large than the non-working flank of the gear teeth, make the both sides of worm screw and the helical gear gear teeth all produce asymmetric flank profil curved surface, can improve the tooth root bending fatigue strength of the gear teeth so on the one hand, increase its bearing capacity, can guarantee that again helical gear tooth top has certain width simultaneously, avoid the phenomenon of gear teeth broken teeth, shock resistance while improving its transmission.With respect to the symmetrical involute worm Worm wheel transmission mechanism of conventional equal modulus used on current engineering, the utlity model has the advantages such as cost is low, efficiency is high, heating is few.Compare with existing involute worm spiral gear drive mechanism, the utlity model has the advantages such as bearing capacity is large, the life-span is long.

The accompanying drawing explanation

The structural representation that Fig. 1 is worm screw of the present utility model;

Fig. 2 is helical gear structural representation of the present utility model;

Fig. 3 is helical gear contrate tooth profile schematic diagram of the present utility model.

Embodiment

For content of the present utility model more easily is expressly understood, below according to specific embodiment also by reference to the accompanying drawings, the utility model is described in further detail.

As shown in Figures 1 to 3, a kind of asymmetric involute worm helical gear pair, comprise worm screw 1 and helical gear 2, the gear teeth both sides of worm screw 1 have respectively worm meshing side flank profil 3 and the non-engagement side flank profil 4 of worm screw, the gear teeth both sides of helical gear 2 have respectively helical gear engagement side flank profil 5 and the non-engagement side flank profil 6 of helical gear, wherein, the axial module of worm screw 1 is m ₁, the transverse module of helical gear 2 is m ₂, the pressure angle of worm meshing side flank profil 3 is α ₁, the pressure angle of the non-engagement side flank profil 4 of worm screw is α ₂, the pressure angle of helical gear engagement side flank profil 5 is α ₃, the pressure angle of the non-engagement side flank profil 6 of helical gear is α ₄, the addendum coefficient of worm meshing side flank profil 3 is

, the addendum coefficient of the non-engagement side flank profil 4 of worm screw is

, the tip clearance coefficient of worm meshing side flank profil 3 is

, the tip clearance coefficient of the non-engagement side flank profil 4 of worm screw is

, in the situation that worm screw 1, helical gear 2 diaxon angle Σ=90 °, in order to guarantee worm and helical gear energy correct engagement, meet following four conditions:

a、α ₁＞α ₂，α ₃＞α ₄；

B, work as m ₁=m ₂the time, α ₁=α ₃, α ₂=α ₄; Work as m ₁≠ m ₂the time, m ₁cos α ₁=m ₂cos α ₃, m ₁cos α ₂=m ₂cos α ₄;

c、 $h_{\mathrm{ad}}^{*}=h_{\mathrm{ac}}^{*}+c_c^{*}-(1-\sin {\mathrm{\&alpha;}}_1)\frac{\frac{\mathrm{\&pi;}{\mathrm{<figure-callout\; id="1"\; label="m"\; filenames="HDA00003443569100011.png"\; state="\{\{state\}\}">m</figure-callout>}}_1}{2}-(\tan {\mathrm{\&alpha;}}_2+\tan {\mathrm{\&alpha;}}_1)(h_{\mathrm{ac}}^{*}{\mathrm{<figure-callout\; id="1"\; label="m"\; filenames="HDA00003443569100011.png"\; state="\{\{state\}\}">m</figure-callout>}}_1+c_c^{*}{m}_1)}{\sec {\mathrm{\&alpha;}}_2+\sec {\mathrm{\&alpha;}}_1-\tan {\mathrm{\&alpha;}}_2-\tan {\mathrm{\&alpha;}}_1};$

d、 $c_d^{*}=(1-\sin {\mathrm{\&alpha;}}_1)\frac{\frac{\mathrm{\&pi;}}{2}-(\tan {\mathrm{\&alpha;}}_2+\tan {\mathrm{\&alpha;}}_1)(h_{\mathrm{ac}}^{*}+c_c^{*})}{\sec {\mathrm{\&alpha;}}_2+\sec {\mathrm{\&alpha;}}_1-\tan {\mathrm{\&alpha;}}_2-\tan {\mathrm{\&alpha;}}_1}.$

Worm screw 1 is made of metal.Helical gear 2 is made by metal or plastics.

The major parameter design of worm and helical gear of the present utility model is as follows:

1) the axial module m of worm screw 1 ₁transverse module m with helical gear 2 ₂can equate (to be m ₁=m ₂), also can be unequal (be m ₁≠ m ₂), m wherein ₁, m ₂the value size choose or make by oneself as required according to the gear handbook;

2) flank profil of worm screw 1 gear teeth both sides is asymmetric, and the pressure angle of getting worm meshing side flank profil 3 is α ₁the pressure angle of spending, get the non-engagement side flank profil 4 of worm screw is α ₂degree, and α ₁>α ₂; α wherein ₁, α ₂the value size under the prerequisite that does not affect gear teeth shock resistance, can need to make by oneself according to the user;

3) flank profil of helical gear 2 gear teeth both sides is asymmetric, and the pressure angle of getting helical gear engagement side flank profil 5 is α ₃the pressure angle of spending, get the non-engagement side flank profil 6 of helical gear is α ₄degree, and α ₃>α ₄; α wherein ₃, α ₄the value size under the prerequisite that does not affect gear teeth shock resistance, can need to make by oneself according to the user;

4) worm screw is often metal-made, and helical gear can be metal-made, also can be plastics, and when helical gear is plastics, and not only stable drive, compact structure but also noise are low and have a self-lubricating property.

5) work as m ₁=m ₂the time, α ₁=α ₃, α ₂=α ₄;

6) work as m ₁≠ m ₂the time, the pressure angle of engagement side meets m ₁cos α ₁=m ₂cos α ₃, the pressure angle of non-engagement side meets m ₁cos α ₂=m ₂cos α ₄;

7) number, the diametral quotient of getting worm screw are respectively z ₁, q, wherein z ₁, q value can be with reference to the gear handbook, reference circle of worm angle of lead

degree, worm meshing side group circle angle of lead γ _bd=arccos (cos γ cos α ₁) degree; The non-engagement side base lead angle of worm screw γ _bc=arccos (cos γ cos α ₂) degree;

8) get the standard pitch diameter d of worm screw ₁=m ₁the q millimeter, worm meshing side group circular diameter

millimeter, the non-engagement side base circle diameter (BCD) of worm screw

millimeter;

9) addendum coefficient of getting worm meshing side flank profil is

the addendum coefficient of the non-engagement side flank profil of worm screw is

the tip clearance coefficient of worm meshing side flank profil is the tip clearance coefficient of the non-engagement side flank profil of worm screw is

and meet:

$h_{\mathrm{ad}}^{*}=h_{\mathrm{ac}}^{*}+c_c^{*}-(1-\sin {\mathrm{\&alpha;}}_1)\frac{\frac{\mathrm{\&pi;}{\mathrm{<figure-callout\; id="1"\; label="m"\; filenames="HDA00003443569100011.png"\; state="\{\{state\}\}">m</figure-callout>}}_1}{2}-(\tan {\mathrm{\&alpha;}}_2+\tan {\mathrm{\&alpha;}}_1)(h_{\mathrm{ac}}^{*}{\mathrm{<figure-callout\; id="1"\; label="m"\; filenames="HDA00003443569100011.png"\; state="\{\{state\}\}">m</figure-callout>}}_1+c_c^{*}{m}_1)}{\sec {\mathrm{\&alpha;}}_2+\sec {\mathrm{\&alpha;}}_1-\tan {\mathrm{\&alpha;}}_2-\tan {\mathrm{\&alpha;}}_1},$

$c_d^{*}=(1-\sin {\mathrm{\&alpha;}}_1)\frac{\frac{\mathrm{\&pi;}}{2}-(\tan {\mathrm{\&alpha;}}_2+\tan {\mathrm{\&alpha;}}_1)(h_{\mathrm{ac}}^{*}+c_c^{*})}{\sec {\mathrm{\&alpha;}}_2+\sec {\mathrm{\&alpha;}}_1-\tan {\mathrm{\&alpha;}}_2-\tan {\mathrm{\&alpha;}}_1},$ Wherein value desirable $h_{\mathrm{ac}}^{*}=1.0$ ,

also can need to make by oneself according to the user, in formula, all the other each parameter meanings are the same;

10) get d _a1for the tip diameter of worm screw,

millimeter, in formula, each parameter meaning is the same;

11) getting the helical gear number of teeth is z ₂, beveled gear teeth outside diameter circle

millimeter, in formula, each parameter meaning is the same;

Working principle of the present utility model is as follows:

In the design of worm and helical gear, increase pressure angle and can improve the tooth root bending fatigue strength, thereby improve its bearing capacity, for the symmetrical involute worm spiral gear drive mechanism of routine, if increase the pressure angle of gear teeth both sides simultaneously, will cause the attenuation of helical gear tooth top, the possibility that adds the large helical gear broken teeth, the shock resistance that is the helical gear gear teeth will descend, in worm and helical gear pair of the present utility model, when worm drive, the stressing conditions of considering the working surface of the gear teeth and non-working surface is different, the working flank of the gear teeth is that the pressure angle of engagement side flank profil is that the pressure angle of non-engagement side flank profil is large than the non-working flank of the gear teeth, make the both sides of worm screw and the helical gear gear teeth all produce asymmetric flank profil curved surface, can improve the tooth root bending fatigue strength of the gear teeth so on the one hand, increase its bearing capacity, can guarantee that again helical gear tooth top has certain width simultaneously, avoid the phenomenon of gear teeth broken teeth, shock resistance while improving its transmission.With respect to the symmetrical involute worm Worm wheel transmission mechanism of conventional equal modulus used on current engineering, the utlity model has the advantages such as cost is low, efficiency is high, heating is few.Compare with existing involute worm spiral gear drive mechanism, the utlity model has the advantages such as bearing capacity is large, the life-span is long.

Above-described specific embodiment; technical problem, technological scheme and beneficial effect to solution of the present utility model further describe; institute is understood that; the foregoing is only specific embodiment of the utility model; be not limited to the utility model; all within spirit of the present utility model and principle, any modification of making, be equal to replacement, improvement etc., within all should being included in protection domain of the present utility model.

Claims (3)

1. an asymmetric involute worm helical gear pair, comprise worm screw (1) and helical gear (2), it is characterized in that: the gear teeth both sides of worm screw (1) have respectively worm meshing side flank profil (3) and the non-engagement side flank profil of worm screw (4), the gear teeth both sides of helical gear (2) have respectively helical gear engagement side flank profil (5) and the non-engagement side flank profil of helical gear (6), wherein, the axial module of worm screw (1) is m ₁, the transverse module of helical gear (2) is m ₂, the pressure angle of worm meshing side flank profil (3) is α ₁, the pressure angle of the non-engagement side flank profil of worm screw (4) is α ₂, the pressure angle of helical gear engagement side flank profil (5) is α ₃, the pressure angle of the non-engagement side flank profil of helical gear (6) is α ₄, the addendum coefficient of worm meshing side flank profil (3) is

, the addendum coefficient of the non-engagement side flank profil of worm screw (4) is

, the tip clearance coefficient of worm meshing side flank profil (3) is

, the tip clearance coefficient of the non-engagement side flank profil of worm screw (4) is

, in the situation that worm screw (1), helical gear (2) diaxon angle Σ=90 °, in order to guarantee worm and helical gear energy correct engagement, meet following four conditions:

a、α ₁＞α ₂，α ₃＞α ₄；

B, work as m ₁=m ₂the time, α ₁=α ₃, α ₂=α ₄; Work as m ₁≠ m ₂the time, m ₁cos α ₁=m ₂cos α ₃, m ₁cos α ₂=m ₂cos α ₄;

c、 $h_{\mathrm{ad}}^{*}=h_{\mathrm{ac}}^{*}+c_c^{*}-(1-\sin {\mathrm{\&alpha;}}_1)\frac{\frac{\mathrm{\&pi;}{m}_1}{2}-(\tan {\mathrm{\&alpha;}}_2+\tan {\mathrm{\&alpha;}}_1)(h_{\mathrm{ac}}^{*}{m}_1+c_c^{*}{m}_1)}{\sec {\mathrm{\&alpha;}}_2+\sec {\mathrm{\&alpha;}}_1-\tan {\mathrm{\&alpha;}}_2-\tan {\mathrm{\&alpha;}}_1};$

d、 $c_d^{*}=(1-\sin {\mathrm{\&alpha;}}_1)\frac{\frac{\mathrm{\&pi;}}{2}-(\tan {\mathrm{\&alpha;}}_2+\tan {\mathrm{\&alpha;}}_1)(h_{\mathrm{ac}}^{*}+c_c^{*})}{\sec {\mathrm{\&alpha;}}_2+\sec {\mathrm{\&alpha;}}_1-\tan {\mathrm{\&alpha;}}_2-\tan {\mathrm{\&alpha;}}_1}.$

2. a kind of asymmetric involute worm helical gear pair according to claim 1, it is characterized in that: described worm screw (1) is made of metal.

3. a kind of asymmetric involute worm helical gear pair according to claim 1 and 2, it is characterized in that: described helical gear (2) is made by metal or plastics.

Images