WO2004020859A1

WO2004020859A1 - Constant velocity universal joint with less axles and can bend a greater angle

Info

Publication number: WO2004020859A1
Application number: PCT/ZA2003/000120
Authority: WO
Inventors: Kwok-Wah Pun
Original assignee: Kwok-Wah Pun
Priority date: 2002-08-28
Filing date: 2003-08-21
Publication date: 2004-03-11
Also published as: CN1688830A; AU2003256445A1

Abstract

The present subject-matter provides a constant velocity universal joint (CVUJ) with less axles, from 4 minimized into 3, and its bearings from ordinary 8 into 4 or even less to minimize the work of maintenance, and this joint can bend and angle from ordinary 45 degrees into 60 or even more to let the driven wheel of a car can turn more for easier parking or running in a narrow crowded roads when compared with the existing one of Double Cardan CVUJ. The subject-matter is based on the principle of ordinary universal joints with hinges and not rolling upon steel balls. It comprises an in-put shaft hinged to its yoke through one axis, and an out-put shaft also hinged to its yoke through another axis, and these two yokes (13) were combined together by only one axis position (not the traditional two axes), perpendicular to that two yoke axes like a cross, so that this combined axis will bend just like the angle bisector of that two shafts to maintain its constant velocity by a few methods, firstly, by using a section of gear teeth mesh at both ends of the shafts' teeth were so polished so that it can turn longitudinally as usual gear, and also sideways, to provide a larger solid angle of turning from ordinary 45 degrees into 60 or even more.

Description

CONSTANT VELOCITY UNIVERSAL JOINT WITH LESS AXLES AND CAN BEND A GREATER ANGLE

The purpose of this invention is to provide a constant velocity universal joint (c v u j) with less axles, from 4 minimized into 3, and its bearings from ordinary 8 into 4 or even less to minimize the work of maintenance, and this joint can bend an angle from ordinary 45 degrees into 60 or even more to let the driven wheel of a car can turn _ς more for easier parking or running in a narrow crowded roads when compared with the existing one of Double Cardan C V U J invented ten years ago in U.S.A. which is too bulky and long to fit to the wheel axles, but just used at the back rear shafts, and the existing Rzebba C N J is too complicated in polishing its 12 race tracks, cage and 6 balls in the manufacture and its maintenance. There this invention consists fewer parts, and can bend a greater angle and cost less.

This invention of constant velocity universal joint (C N U J) is based on the principle of ordinary universal joints with hinges and not rolling upon steel balls. It comprises an in-put shaft hinged to its yoke through one axis, and an out-put shaft also hinged to its yoke through another axis, and these two yokes were combined together by only ιS . one axis position (not the traditional two axes), perpendicular to that two yoke axes like a cross, so that this combined axis will Bend just like the angle bisector of that two shafts to maintain its constant velocity by a few methods, firstly, by using a section of gear teeth mesh at both ends of the shafts' teeth were so polished so that it can turn longitudinally as usual gear, and also sideways, to provide a larger solid _a6 angle of turning from ordinary 45 degrees into 60 or even more, while the second method is to connect these two shafts by spring rods, by the principle of force on action angle equals to that of angle of reaction to bring that in and out-put shafts running in equal velocity, thirdly is by any existing methods including the tube enclosing a ball in angle turning to perform an angle bisector.The said shaft axes can be hinged by a straight pin or bolt to its yokes, or sliding along upon a curvature on a metal ring, performing the same principle but just hinged on a sliding ring style, -wherein the combined common hinge acts also as a yoke hinge, therefore two bush bearings were sufficient to service the three axes hinges making it as a most simplified type of C N U J of less components when compared with the existing

.tø Double Cardan and that of six metal balls Rzebba C N J of tens years ago for any mechanic uses.

In order to give the history and background of this c v u j invention more clearly, diagrams in figure 1 and 2 may be referred to; wherein on the top page, it points out universal joints may be classified into two types as motion of turning by sliding on

&£ .. surface or on rollers, while the other type is turning through a pin hinge, like the heavy door of the bank safe can be closed with a finger, because it is hinged by a pin (β supported by an oiled bush or bearing ( jand easy to .maintain or renew, like those of single or double universal joints of Hookes in 1700, but they have a very limitation to transmit the same angle rotation velocity, only effective within around 15 degrees, if

Vo more than that say 40 degrees, the out-put velocity may less 40% as the in-put shaft, and after turning 90 degrees, it may greater than the in-put by +40% as shown in the graph in Fig.l F in the line of 3? while most universal joints when jointed together, we need to hold it by a holder as (4i) to make the joint rod to two (δ)services a an angle bisector, otherwise the out-put shaft may turn any direction and spee ^' fδ)in the t_{$ same graph F, therefore in order to perform a more steady out-put, a double Cardan U J were introduced for motor cars in the year of 1900 as in Fig.1C, herein it shows its in-put yoke \T?were jointed to its out-put yoke ({$] by a tube enclosed a ball method ^~(β) to service as the angle bisector of that two shafts, so that its velocity will kept equal as in graph F, in the normal position O, no fluctuation of angle changes, but "e with some weared out in the bearings ,some changes may happened as shown in line

(t B),tberefore making the whole design quite bulky and long, therefore my invention is to simplify this double U J by putting axes of its coupling yoke joints into just a combined one as shown in Fig. ID in as ' ( l)and (/^combined as just one axis CY only, and besides using ^' (B}a system of gear portion meshed teeth may be used as its _ff angle bisector, making the two shaft can turn more than 60 degrees. While Fig. IE is just a modification of D, shows also the same principle of having a simplified 3 axes instead of 4 in C can do the same function as D but just go through theirs yoke axes by a ring instead of a straight bolt.

In Fig.2A, it shows that only surface sliding (jj) of a joint is quite weak, therefore the _t> -U J of Tracta of 1926 for the first front wheel driven car can last only ten years because of low efficiency in power out-put. When ball roller were invented as C N J by Sweiss in 1923 its friction is less, but as its bending angle were only 35 degrees, a few year later it was replaced by Rzebba C N J in 1935, in Fig.2C with 12 raσe-frack to be cut to mesh 6 steel balls enclosed by a cage as its angle bisector, having^"45 ς _. degrees to turn for the front wheels, while its joint near the gear box can be its own U J or to use a tripod joint which can serviced as a slip-joint (itf). Some French cars use a tripod inside a bowl meshes to a 3-finger forg as shown in (ji ), (1 ) in Fig.2D can turn a reasonable 40 degrees. All the above design based on sliding ball or rollers, , which may required to run about 40 mm on their race track (j .) during its maximum" η^ _. turn of the wheel, therefore after certain mileage or unexpected pumping its race track and cage may weared out with its dirt as : , ((f), by a fraction of a mm thickness, to maintain these, either a new one were replaced, or need to polish them smooth of wider track, usually, for example, from 40.mm into 40.16 mm, and to replace all 6 steel balls into these new diameter by a polishing machine / ^ ),on its ball (/^t),race _ηs (jξ) and^' cage (£e).on Fig.2E. The above cases shows why my invention would like to base on the principle of pin hinges with a easier replaced oiling bushes or needle thin bearings as shown (V) and (2.) in Fig.lA, and it would be more smooth, less vibration, easier to make, and therefore cost less.

While in Fig. 1 (C, D, E) is an enlarged figure as last page, but try to show the _So relationship between their axes and the way how it axes and bush bearings can be minimized and its angle can be enlarged, steps by steps. In Fig.lC shows the combination of two universal joints by using a coupling yoke ('/$), and 2 cross were applied, making it quite bulky with 4 + 4 = 8 axes, and 8 bearings, need a spring /) to compress a ball seat (_*,z). Making a maximum turning angle about 50 degrees before w its ball in its angle bisector may come out from its tube end. In compared with this invention in Fig. ID, its coupling yoke can be omitted and their two axes in it yoke can be simplified into one combined yoke axis without 2 hollow crosses as shown as ( / 1 + /^'2 = /3^") and its two pair of yoke bearings can be minimized into two bolts hinged bushes or bearings, while the total length between the two yokes end can be shortened about half as in (z^'5 _t IH.) to (zS_f zb) in Fig. ID, and if the gear teeth mesh were

*> used instead the tube and ball (tb), a greater bending angle of 90 degrees can be applied, Wherein in Fig. IE shows a even simplified universal joint can be make through the same 3 axes principle, by letting all these 3 axes lie through a strong ring curvature path, therefore only 2 completed oil bush bearing to do the work of 3 axes, ar including the bending angle for in-put yoke (? f) and (v § ) of out-put yoke, while when it slides along its ring curvature, it works for the combined yoke axis, and is able to turn up to 120 degrees as shown in (13)-

Wherein in Fig.3 to 6, shows how several angle bisector of this invention of C N U J can work and its geometric path relations in Fig.3 it shows why the traditional tube

_/&0_ enclosing a ball jointed at both end of the shaft cannot perform a perfect angle bisector, were due to 2 reasons, one is that the ball will becoming loose or even come out of its tube at around 50 degrees, therefore its safety working angle should around 45 degrees, while the other reason is; at its maximum angle, its triangle AOB AO = OB and <a = <b, AC = CB, why OC are common to form 2 congruent triangles to act

JββL ^{t o} motion on either sides, but while the <a becoming smaller the projection of line AO on to the bottom AB as AO1 becoming shorter than 01 B, therefore <al is greater than <bl making two sides motion not 100% equal, but still quite close to acceptable 95%. While in Fig.4, it show how one or more spring rods (*τ) may be used as a force to hold the angle bisector of the combined yoke axis (Vs. ), because the _ffσ action force on <a must equal to its reaction force in <b, and is the same for the spiral (?8^ spring type in Fig.4B These angles bisector position can maintain if the torque force is relatively not too big.

In Fig.5 shows the geometric position of the gear teeth meshed type of about 10 teeth out of a circle ratio) is best to use, while only take 3 of the teeth on both sides of the

_(lς shaft ends is sufficient to hold these 2 shafts in firm position with always have 2 points touches each others like position (i'j) and (jό), while the bending of the combined yoke axis passes through the center of the teeth where 2 teeth meets no matter how the other axes move as shown in (B to Bl to B2 to B3)₃ and even to (B4), there is still a position to mesh 2 teeth together in (C2). In Fig.6 shows only 3 no teeth is sufficient to maintain always 2 point (C and D or Dl) touches firmly to hold the in-put yoke axle (A to B) at the top or to lower position (a toBl) while there are 2 touching point at GΛ)and ⁽l°), enable a larger angle turning from 60 to 90 and to 120 degrees. While in Fig.6C shows the contour line seen in front in (C) and also (C2) from the side, to show the end teeth on (A) touches the (B) end teeth at a relative

«$^■ _... , osition meshes at 90 degrees, maintains 2 point s touches firmly to each other.

Fig.7 shows a C N U J of 3 axes using gear mesh to perform an angle bisector for the in-put shaft connected to its yoke at it axle at (A) and other out-put to the wheel axle) ( 2.7) connected to its yoke axis ( 13 ) at (B); while 2 bolts (2$) enclosed by a bush or needle bearing fø) go through the combined yoke axis line (^"/' f), the right side is to f3ø. .. connect to a longer shaft to the gear box through a sliding joint (3_$), wherein a rubber seal (31) is.put to enclose some oil inside (21) for lubrication.

In Fig. 8 is the top view of Fig.7,seen through the line of (13 )_s:ib υ4tv f ^t(3)

Hi .

In Fig.9, it shows the applied position of this C V U J, mainly used near to the wheel ^{• •'} axle on both front wheels (3 H-) or Rear Wheel^'^) when it is a 4 wheel driving or the rear axle for back driving, it shows also 60 degree of front wheel steering enable most car can park and run on a narrow road much easier as in (36).

(37) λ^tt.o Wherein, in Fig.10 shows how the C V U J_Λbe combined with other things, in top A, where, the joint is very short, and the particular SIZE of any car wheel axle can be

(38/ welded on to it, while the other side can clip on to any size of power shaft, while in

(lj! j ) the whole shaft may include a tripod sliding joint near the gear-box, the other ends with a specified wheelshaft. While in the universal joint of (UJ3) consists of a

^ length slip-joint to hold any other type and size of this invention like the Ring type, or the spring bending type mixed together to fit the requirement. &ι)

(HZ)

In Fig.11, it shows the C V U J of the Ring type,_Awhere the end of both in and out-put shaft has a set of teeth meshed at the ring center (C), where some bolt (z%) were needed to fit up, two shaft turns up and down through it in-put yoke shaft (i^*/), n the

_/5₀ same time to screw up a wheel shaft (2.7) and a slip-joint (3°), while the yokes can turn sideways through its combined center (C), by just sliding along the curvature of the ring as in ( \^"3) direction. And provides a cross-section view through line (b to bl) for the Fig.12, wherein the cross-section of the ring is seen in ( $), enclosing by yoke (^"7^") and ('. 8 ), and preferable, two pair of thin oil bushes can fitted to enclose them as (_*^•< ? ι_$y (HG-). Wherein Fig.13. to show how the fork like teeth bar ( fe, * ) ^can slided into the ring, enclosing two pair of yokes, and would be complete enclosing the ring when input end (7) and out-put end ( 8Q were bolted in by 4 bolts ( £). Just like Fig.7 and Fig.11 seal (3t) and lubricant ($1.) were enclosed to them, it will run very smooth. In Fig.14, it shows the compact and simple top view (A) and the side view (B) of this C r6 ., V U J in a Ring style which is obvious can turn a very great angle around 60, 90, to 120 degrees.

Claims

I claim:

1. A constant velocity joint for joining a driving member to a driven member for joint rotation, the driving member rotating about a first axis arid the driven member rotating about a second axis, the first and second axes being capable of misalignment, comprising: an input shaft hinged to a yoke as first axis, and an output shaft also hinged to a yoke as second axis, and these two yokes were hinged together by only one common axis connection (not the traditional Double Cardan one of two axes), and is perpendicular to the direction to that two yoke axes so that this common axis can perform always as an angle bisector of that two shafts by a few methods as: by using a sector of gear of a few teeth, meshed at both ends of the shafts resting on a straight line direction first, then to limit and control the input shaft angle always equals to the output shaft, capable even in solid angle direction of turning from 45 degrees into 60 or even more; of constant rotation velocity transmission between two shafts: while the second method is to connect the two shafts by spring or spring rods, by using the principle of force of reactions of angle of input shaft equals to the angle of output shaft, geometrically making input action equals to the output action, thus to perform constant velocity: while the third method is the existing methods, including a tubing enclosing a ball of just fit to slide in, geometrically, making the input shape equals to the output shape to perform constant velocity, while all the above three may be classified as three axes hinged by straight pins or bolts, as a STRAIGHT PIN HINGED TYPE of c v joint; wherein its principle still holds in another configurations as: the three yoke hinges may rest on the curvature of a strong metal ring wherein the center of the ring performs as the common axis jointing the two yokes, say, moving horizontally, as an angle bisector joint two shafts by the same above three methods, limited and controlling the input shaft moving up and down at the same angle as the output shaft to perform a constant velocity power transmission as a RING HINGED TYPE of c v joint; wherein only two visible hinges or bearing shells were sufficient to serve the work of a three axes joint, making it as a most simplified type of hinged constant velocity joint as compared with the existing double Cardan c v joint.

2. The constant velocity joint of claim 1 wherein a pair of thrust washer were placed in between the yoke faces and the shaft faces in its two hinges, and a bearing or bearing shell were placed in the common, yokes hinge, in order to hold more lubricant and to reduce the friction of the hinges to prolong its life, and can be replaced in reconditioning.

3. The constant velocity joint of claim 1 wherein the yoke can be make not so thick to allow greater angle of bending and the said teeth were so polished so that it can mesh each other longitudinally as usual gear, and to polish little bite pointed and smooth edge to allow sideway bending more, so as to perform a larger solid angle bending of 45 degree and even more than that.

4. The constant velocity joint of claim 1 wherein the input shaft and the output shaft holds two circular dish circling round the shaft to hold a rubber boot to perform a complete grease holding chamber in running.

5. The constant velocity joint of claim 1 wherein the joint can be mainly used attached to the outer wheel in the half shaft while the inner joint attached to gear box can be the same c v joint or to use tripot or any applicable joint; and moreover, this great bending angle c v joint of more than 45 degrees may be used as a proshaft for sports car of greater vibration, and to be installed in front wheels for greater angle of steering.

6. The constant velocity joint substantially as described herein with reference to Figures 1 to 4 of the accompanying drawings.