CN100360809C

CN100360809C - Unequal-tooth-number screw profile for high-flow high-pressure dual-screen pump

Info

Publication number: CN100360809C
Application number: CNB2005100609769A
Authority: CN
Inventors: 陈行; 陈光亮
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-09-30
Filing date: 2005-09-30
Publication date: 2008-01-09
Anticipated expiration: 2025-09-30
Also published as: CN1743677A

Abstract

The present invention discloses a tooth shape of a screw with unequal tooth numbers for a double-screw pump with large flow and high pressure. A screw pump comprises two screws, wherein one screw is a double-head screw, and the other screw is a three-head screw. When the screw of the present invention is used for the screw pump, the screw of the present invention has the advantages of short seal line, good sealing performance, high efficiency, low noise, simple screw curve, convenient processing and low processing cost; in addition, the output flow and the output pressure of the screw pump are increased in multiples.

Description

A kind of tooth shape of screw that does not wait the big-flow high-pressure two screw pump of the number of teeth

Technical field

The present invention relates to the Course Exercise in Machinery Elements Design processing technique field, especially, relate to a kind of tooth shape of screw that does not wait the big-flow high-pressure two screw pump of the number of teeth.

Background technique

The profile of tooth of two screw pump screw rod have cycloidal tooth profile (patent No.: 99201251.1), 96236524.6) and involute profile etc. the spiral of Archimedes tooth shape of screw (patent No.:.But all above-mentioned profiles of tooth are single head, and the cross section of two screw rods is all identical.The profile of tooth of the two screw pump screw rod of minority also has double end, but two screw rods all are double ends, and the number of teeth equates that shape of cross section is identical, and can not seal fully.No matter be screw rod single head or double end, their common drawback is: 1, specific discharge is little, and 2, delivery pressure is low.

Profile of tooth of the present invention is compared with above-mentioned various profiles of tooth, and specific discharge and delivery pressure increase exponentially, and processing is still more convenient.

Summary of the invention

The purpose of this invention is to provide a kind of tooth shape of screw that does not wait the big-flow high-pressure two screw pump of the number of teeth, the profile of tooth of one root screw rod is a double end, and another root is three.

In order to achieve the above object, the technical solution used in the present invention is as follows:

A kind of tooth shape of screw that does not wait the big-flow high-pressure two screw pump of the number of teeth, screw pump comprises two screw rods, and a screw rod is a double threaded screw, and another root screw rod is three screw rods;

The profile of tooth of every screw rod of three screw rods is identical, and evenly distributes along circumference, and wherein one is linked in sequence by top circle camber line aj, radial alignment section ab, generalized cycloidal bc, root circle camber line cd, generalized cycloidal de and radial alignment section ef and forms.Wherein, top circle camber line aj and root circle camber line cd are with o ₁Circular arc for the center of circle.

The profile of tooth of every screw rod of double threaded screw is identical, and be symmetrically distributed along circumference, wherein one is linked in sequence by envelope f ' e ', generalized cycloidal a ' f ', top circle camber line a ' b ', generalized cycloidal b ' c ', envelope c ' d ' and root circle camber line d ' g ' and forms; Wherein, top circle camber line a ' b ' and root circle camber line d ' g ' are with o ₂Circular arc for the center of circle.

The radian of the root circle camber line d ' g ' of described double threaded screw is the half as much again of the radian of three screw rod top circle camber line aj, and the radian of described double threaded screw top circle camber line a ' b ' is the half as much again of three screw rod root circle camber line cd radians.

Further, described radial alignment section ab and ef also can be circular arc, cycloid or involute.

Further, the helical pitch of described three tooth shape of screw is half as much agains of double threaded screw.

Advantage of the present invention is: potted line is shorter, good seal performance; Output flow and delivery pressure are multiplied, the efficient height, and running is steady, and noise is little; Screw curve is simple, and is easy to process, and processing cost is low; Screw rod can run up.

Description of drawings

Fig. 1 is the longitudinal section view of three screw rods of the present invention;

Fig. 2 is the longitudinal section view of double threaded screw of the present invention;

Fig. 3 is two screw rods illustrated in figures 1 and 2 engagement figure when doing to roll;

Fig. 4 is two screw rods illustrated in figures 1 and 2 pitch curve figure when doing to roll.

Embodiment

Below in conjunction with accompanying drawing, the present invention is done detailed explanation.

Screw pump of the present invention comprises two screw rods, and a screw rod is three screw rods, and another root screw rod is a double threaded screw.

Fig. 1 shows the shape of three screw rod radial cross sections of the present invention, the profile of tooth of every screw rod of three screw rods is identical, and evenly distribute along circumference, wherein one is linked in sequence by top circle camber line aj, radial alignment section ab, generalized cycloidal bc, root circle camber line cd, generalized cycloidal de and radial alignment section ef and forms.Wherein, top circle camber line aj and root circle camber line cd are with o ₁Be the circular arc in the center of circle, the radian of root circle camber line cd and hi is all adjustable, and its limiting value is zero, the length-adjustable of radial alignment section ab and ef, and ab and ef also can be circular arc, cycloid, involute or other curves, also can omit.

Fig. 2 shows the shape of double threaded screw radial cross section of the present invention, the profile of tooth of every screw rod of double threaded screw is identical, and be symmetrically distributed along circumference, wherein one is linked in sequence by envelope f ' e ', generalized cycloidal a ' f ', top circle camber line a ' b ', generalized cycloidal b ' c ', envelope c ' d ' and root circle camber line d ' g ' and forms; Wherein, top circle camber line a ' b ' and root circle camber line d ' g ' are with o ₂Circular arc for the center of circle.

When double threaded screw and three screw rods with 3: 2 speed ratio when rotate in the center of circle separately, generalized cycloidal bc and de are respectively b ' point on the double threaded screw and the conjugate curve that formed on three screw rods in a ' o'clock on three screw rods, generalized cycloidal a ' f ' and b ' c ' are respectively three e point and conjugate curve of forming on double threaded screw of b point on the screw rod on the double threaded screw, and envelope f ' e ' and c ' d ' are respectively three straightway ef and conjugate curve of forming on double threaded screw of ab on the screw rod.

The radian of the root circle camber line d ' g ' of double threaded screw is the half as much again of the radian of three screw rod top circle camber line aj, and the radian of double threaded screw top circle camber line a ' b ' is the half as much again of three screw rod root circle camber line cd radians.The Outside radius of three screw rods is identical with the Outside radius of double threaded screw, and the root radius of three screw rods is identical with the root radius of double threaded screw.

The helical pitch of three tooth shape of screw is half as much agains of double threaded screw, and the length of screw rod is slightly larger than the helical pitch of three screw rods, and the two screw rods rotation direction is opposite.

Fig. 3 shows the meshing relation of two screw rods correspondence of the present invention, the pitch curve of three screw rod top circle aj and root circle cd correspondence is respectively the root circle d ' g ' and the top circle a ' b ' of double threaded screw, put a ' on the double threaded screw and put b ' and correspond respectively to generalized cycloidal de and generalized cycloidal bc on three screw rods, point b and some e correspond respectively to generalized cycloidal b ' c ' and generalized cycloidal a ' f ' on the double threaded screw on three screw rods, and radial alignment section ab and ef correspond respectively to envelope c ' d ' and the f ' e ' on the double threaded screw on three screw rods.

As Fig. 4, shown in Figure 5, when two screw rods rolled relatively, three head rods will form the space pitch curve on double threaded screw, and double threaded screw also can form corresponding pitch curve on three screw rods.Because it is continuous rotating, two pitch curves have been blocked the input cavity and the output cavity of pump, and constantly push ahead, thereby produce compressed fluid.

The foregoing description is used for the present invention that explains, rather than limits the invention, and in the protection domain of spirit of the present invention and claim, any modification and change to the present invention makes all fall into protection scope of the present invention.

Claims

1, a kind of tooth shape of screw that does not wait the big-flow high-pressure two screw pump of the number of teeth, screw pump comprises two screw rods, and a screw rod is a double threaded screw, and another root screw rod is three screw rods; It is characterized in that,

The profile of tooth of every screw rod of three screw rods is identical, and evenly distribute along circumference, wherein one is linked in sequence by top circle camber line aj, radial alignment section ab, generalized cycloidal bc, root circle camber line cd, generalized cycloidal de and radial alignment section ef and forms, wherein, top circle camber line aj and root circle camber line cd are the central point o with three screw rods ₁Circular arc for the center of circle;

The profile of tooth of every screw rod of double threaded screw is identical, and be symmetrically distributed along circumference, wherein one is linked in sequence by envelope f ' e ', generalized cycloidal a ' f ', top circle camber line a ' b ', generalized cycloidal b ' c ', envelope c ' d ' and root circle camber line d ' g ' and forms; Wherein, top circle camber line a ' b ' and root circle camber line d ' g ' are the central point o with double threaded screw ₂Circular arc for the center of circle;

The radian of the root circle camber line d ' g ' of described double threaded screw is the half as much again of the radian of three screw rod top circle camber line aj, and the radian of described double threaded screw top circle camber line a ' b ' is the half as much again of three screw rod root circle camber line cd radians; The Outside radius of described three screw rods is identical with the Outside radius of double threaded screw, and the root radius of described three screw rods is identical with the root radius of double threaded screw.

2, the tooth shape of screw that does not wait the big-flow high-pressure two screw pump of the number of teeth according to claim 1 is characterized in that, described three screw rod radial alignment section ab and ef are circular arc, cycloid or involute.

3, the tooth shape of screw that does not wait the big-flow high-pressure two screw pump of the number of teeth according to claim 1 is characterized in that, the helical pitch of described three tooth shape of screw is half as much agains of double threaded screw.