DE8704197U1 - Continuously variable transmission - Google Patents

Description

Description :

is St röter KG Gearbox Construction

Kre eider Str. 117, D- 4000 Düsseldorf 11

Continuously variable transmission

The invention relates to a continuously variable transmission with

following features: I

(a) the transmission has a transmission input and a G&eacgr; t f &igr; 6 b ed j 5 9 j 'i y ;

(fa) in the gear box a planetary carrier with planetary bodies mounted therein is rotatably mounted;

(c) the planetary bodies each rest on ^three supporting bodies with running surfaces concentric with the planet carrier;

(d) at least one of the support bodies is arranged to be axially displaceable in order to adjust the transmission ratio;

(e) an actuating device is provided for its axial displacement;

(f) at least one, in particular two of the support bodies is or are rotatably mounted and connected to the transmission input or output.

Such a gearbox is described in DE-OS 28 25 730. In this gearbox, the gearbox input

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&tgr;&igr; it is connected to a support disk on which &ngr;" running surface &Ggr;I a &eegr; ete &eegr; k &oacgr; r &rgr; ■-■ r roll, which are mounted in a planet carrier. The planetary bodies are designed as conical disks, wherein the angular position of their axes of rotation in relation to the planet carrier is aligned with the K &eegr;&eegr;&pgr; C u "&igr;&eegr;L;&og; This creates a cone surface line. The conical disks rest on a second support body with this surface line, which is designed as a support ring surrounding the planet carrier and the planet bodies. This support ring can be moved axially, so that the cones run at different locations on the surface line and at different distances from the axis of rotation depending on the position of the support ring. The planet bodies are additionally supported with the underside of the cone surface on a third support body, which is designed as a support disk. In this way, the planet bodies are supported three times, ie during their rotation they rest on all three support bodies.

Two suggestions are made for the power transmission to the gearbox output. In one suggestion, the support ring itself is connected to the gearbox output with the interposition of a displacement device, while the support disk resting on the underside of the conical surface of the planar body is held in place and rotationally fixed. In the second embodiment, the situation is reversed, i.e. the support ring is held in a rotationally fixed manner, i.e. only guided axially displaceably, and the support disk resting on the underside of the conical surfaces is connected to the gearbox output. The gearbox input is connected to the support disk.

1- Gearbox output area provides the
Power transmission via balls in wedge-shaped nibs
If a load is applied to the gearbox output, the balls strive to move the Ke iIf Lachen
up to Ia ufen and thereby tension the whole
Systems of supporting bodies and planetary bodies, On c - ese
Way mercer, load dependent more or less high
Contact pressures are generated.

Despite this measure, these gearboxes
load-dependent, a relatively high apparent slip due to changes in the gear ratio under load.
Accordingly, the efficiency at higher speeds is not satisfactory.

The invention is therefore based on the object of
Gearboxes of the type mentioned above are to be designed in such a way that the efficiency losses and the apparent slip
~ic 3 are extremely low.

This task is achieved according to the invention by the
said gearbox is released if it has the following characteristics:

(g) 3"i? Pl 3r< ete ^r <or^er weisen & ir &ogr; Y a &eegr; te L "* a ~ ~ t? _.'' d

if;

'J ·? r -3 r -i e r e ' ^ -■ · t e de

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( j ) the planetary bodies are pivotably mounted with their axes of rotation in a plane passing through these and the three contact surfaces of the support bodies;

(k) The end faces and the outer surface of each planetary body are shaped in such a way that an axial displacement of the displaceable support body can cause the planetary bodies to pivot while maintaining their contact with the support bodies.

According to the invention, the planetary bodies are shaped in such a way that they can be supported on one side of their axes of rotation via their two front sides on a support body and on the other side of the axes of rotation via the outer surface on the third support body. This three-point support is obviously more favorable in terms of efficiency and the change in the transmission ratio under load. In any case, tests have shown that the measured values are considerably more favorable than with the previously known gear. The adjustment of the transmission ratio is also carried out here by the axial displacement of one or two support bodies, which causes the pivoting of the planetary bodies due to their special shape. This results in changes in the radii of the support surfaces, via which the planetary bodies are supported with their front surfaces on the two support bodies. The ratio of the radii then determines the λ over 3 et ζ -j η g 3 ν erha '. tr ^; λ .

I" A js D i !. d &ugr; ng of the invention it is provided that"! the D r ·>&tgr;,&ogr;:' -, '· r ^&lgr; ."^&ggr; PL a ·~-ate r.' ^ '&zgr; ^ r ir essential ?. ' i 3 L 9*ri :.'.·»* ->i rd ,'·'*, ; ew ? ''. 3 , ~ one in U"'ang3 ^r · :-:urj the

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t- Rotational movement of the planetary carrier Horizontal swivel axis

This design is constructive

;■ particularly easy to implement, especially if this

f. both support bodies on the front surfaces outside

&rgr; and the third support body on the inside of the casing

The running surfaces of the support bodies on the front sides of the planetary bodies should be axially opposite each other, i.e. have the same diameter.

In a preferred embodiment, the shells of the planetary bodies have a constriction for the support body to be placed in, which should preferably be rounded. In this way, they produce roughly oval-shaped planetary bodies that can be easily pivoted by moving one of the support bodies. Of course, it is also possible to provide a ring that protrudes from the shell on the outside, which is then enclosed by a corresponding ring groove in the support body.

In a further embodiment of the invention, the planetary bodies are pivotably mounted on the planet carrier at one end. To improve the stability of this mounting, the planetary bodies should be slidably mounted at the other end in guide slots extending in the pivot plane .

': The planetary bodies are conveniently rotatable on

r mounted on non-rotatably held axle bolts.

Due to the given geometric conditions, it is expedient that the support body resting on the shells of the planetary bodies is mounted so as to be axially displaceable, although it is not excluded that d ^; <?

the other two supporting bodies can be used for this purpose.

For structural reasons, it is advantageous if one of the support bodies resting on the end faces of the planetary bodies is arranged in a rotationally fixed manner. Furthermore, the support body resting on the shells of the planetary bodies can be connected to the gearbox input, whereby the support body arranged in a rotationally fixed manner should be located on the input side. The gearbox output is then connected to the support body which rests on the opposite end faces of the planetary bodies .

The invention is illustrated in more detail using an exemplary embodiment in the drawing. It shows a continuously variable transmission (1) in longitudinal section.

The gearbox (1) has a housing (2) into which a gearbox input shaft (3) extends from the right. This gearbox input shaft (3) is usually connected to an electric motor.

The transmission input shaft (3) has a sleeve (4) which is connected to it in a rotationally fixed manner and which is provided with a spur gear (5) on the outside. This is in engagement with an internal gear (6) which is the outer _gear of a support ^body (7) into which the transmission input shaft (3) projects. Its rotary movement is transmitted to the support body (7) by the gear (5, 6).

The support body (7) is mounted in a sliding ring (9) via a ball bearing (3). The ball bearing (8) is mounted in both the sliding ring (9) and the support body (7) in such a way that the support body (7) moves axially η, ; -. t

stands si ' p ■ &pgr; · ■ r 7 e ^r ste ■. * ■ i tte ^r (12/. This is d ^r e µgr; &ogr; ar , ; ed 3 c &idigr;&igr;ü",?r5:";ec . &igr;:' 5 e '. age ^r t ^! jnd «1 e &igr; st aL.3e"3eit'g eine Sp^Tde^i^iHn.,':^ (13· .-jj*. D' es? stent ■ &pgr; E ⁱ ^gri ^£ f lit e &tgr;&Ggr;; erta r. 3 e " t ■ i '. ./ e *■ L a &ugr; * e ^ de &eegr; Ssmde. \ ^&Lgr; U) , d ^ e cnlnrdr'' The movement is converted via the Ve'jte.-iutte^ -"2) into a J« iai. -erscn - eDjrg of the Sc^'ebe^-ng ( 9 -■ ^ ^. ^, which then ^carries the ball ^bearing (3 ⁾ onto the &eegr; supporting body (?). &eegr; j■rj.

A needle roller bearing (15) is mounted coaxially to the gear train ( ¹⁾ . Le (3) and the support sleeve (7). It consists of two roller bearings (16, M) arranged at a distance from one another, which are rigidly connected one behind the other by means of the reinforcements shown. The left-hand roller bearing (17) is mounted on the support sleeve (7) ^by means ^of a needle bearing (IS) ^, while the left-hand roller bearing (17) is accommodated in a ball bearing (19). On the output side, this ball bearing (19) is supported by a locking ring (20), which, on the right, is supported axially by a further ^ball bearing (21) arranged on the other side of the locking ring ( ^{20 )} . Its interior is supported by a support (22), which is fastened by a screw (23) ^- t ze r I : r < e r igr; gi^be CI7) connector.

Between the two columns (16, 17) are P'. anetenkcrcer &iacgr; 2 i·, 25; :e ^: . ass't, of which only two can be seen in this Ars ^; :"t :e:igiich. The other

P j'i··?"':^»'^; 3· &igr; ^ ·'&idigr; · - e &tgr;4;&iacgr; ■-, b &ogr; I &zgr; e &eegr; (26, 27) d - ehs -:j mounted. The axes b '■ I &zgr; e ^r . \ &oacgr; , 27) are mounted at their^ right ends in the right cage disk (16) in a rotationally fixed but pivotable manner. The axis of gravity extends in the initial direction, ie in the case of the planetary bodies (24, 25) shown perpendicular to the plane of the drawing. Dip ir. riipspr view left F &eegr; d &eegr; ri &rgr; r A r. hsb D &iacgr; ? e &eegr; ( ? &eeacgr; . 27; hubs have a rectangular cross-section and are guided in radially extending guide slots (28, 29).

The planetary bodies (24, 25) are approximately diabolo-shaped. They have a casing (32, 33) each provided with a rounded constriction (30, 31), which is delimited on both sides by spherically curved end faces (34, 35) and (36, 37). Both the casings (32, 33) and the end faces (34, 35, 36, 37) are rotationally symmetrical to the axle bolts (26, 27). The end faces (34, 36) shown in this view lie externally ^against a support ring (38) held stationary in the housing (2). The left front faces (35, 37) are also supported on the outside by a support disk (39), whereby the contact surfaces of the support ring (33) and the support disk (39) are on the same radius. On the inside, the planetary bodies (34, 35) are supported by the constrictions (30, 31) in the casing (32, 33) on the support body (7), the curvature of which is adapted to that of the constrictions (30, 31).

6etriebe3iJ5G3r;C!Sseitia 3 π the support disk (39) is a support sleeve C40) formed, within which the ball bearings (19, 21) are arranged. The support sleeve C40) is

two needle bearings (41, 42) are mounted in the housing (2 / "J ^r ·:■ &igr; b 3 r.

A gearbox output shaft (43) extends into the housing (2) from the left, as far as the support sleeve (40). It is mounted in the housing (?) via an angular contact bearing (44) that can absorb axial forces directed in the opposite direction. A shaft seal (45) is also provided. Inside the support sleeve (40), the gearbox output shaft (43) is additionally supported by a needle bearing (46).

The transmission of force to the gearbox output shaft (43) takes place via several balls (47) held in a cage, only one of which can be seen here. These balls (47) lie on the front side of the support sleeve (40) and are guided in wedge-shaped recesses within an annular disk (48) formed onto the gearbox output shaft (43). This type of force transmission results in axial tension between the gearbox output shaft (43) and the support sleeve (40) when the gearbox output shaft (43) is subjected to a load. The annular disk (48) then tends to rotate relative to the support sleeve (40). This in turn results in the balls (47) attempting to run out of the wedge-shaped recesses in the ring disk (48). The axial tension caused by this results in the support disk (39) exerting a greater contact pressure on the end faces (35, 37) of the planetary bodies (24, 25) the higher the load on the gear output shaft (43). The contact pressure on the support ring (38) also increases accordingly.

The transmission output shaft (43) has a blind bore (49)

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in which a screw ^spring (50) is inserted which is subject to dirt. This is supported by ^two washers (51, 52) on the outer ring of the ball bearing (21). The gear output shaft (43) is pressed outwards by this screw spring (50), so that the angular contact ball bearing (44) is under ^a defined preload.

To illustrate the stepless adjustability of the gear (1), the drawing is divided into ^a lower and an upper half. In the lower half, the support body (7) is in a position pushed forward in the direction of the gear output. In this position, the axle bolt (27) moves in an exactly a * i &lgr; !_ &rgr; direction. This means that the end faces (36, 37) rest on the same radius on the support ring (38) and the support disk (39). The speed of a connected electric motor is transmitted to the support body (7) via the gear input shaft (3). This sets the planetary body (25) in rotation via friction in the constriction (3*). The planetary body (25) rolls on the support disk (39) and the support ring (38) and thereby takes the planetary cage (15) with it. In this position, no power transmission takes place, ie the output speed on the gearbox output shaft (43) is zero.

The upper half shows how this gear (1) can be used to transmit power from the transmission input shaft (3) to the transmission output shaft (43). To do this, the support body (7) is moved towards the transmission input from the position shown in the lower half of the drawing, using the means specified above. This results in the planetary body (24) - as is of course also the case

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all other planetary bodies - pivots inwards, namely around the pivot axis of the axle bolt (26) in the right cage disk (16 3). The end faces (34, 35) are curved in such a way that contact with the support ring (38) and the support disk (39) is maintained during this pivoting movement. The same applies to the constriction (3D). As can be seen, the contact surface between the support ring (38) and the end face (34) is located on a much smaller radius to the axle bolt (26) than the contact surface between the support disk (39) and the end face (35). This difference in radius means that the rotary movement transmitted from the support body (7) to the planetary body (24) is transmitted - with the corresponding reduction - to the support disk (39). The output speed can be continuously adjusted by axially moving the support body (7). It is smaller the smaller the inclination of the planetary bodies (24, 25), i.e. the smaller the difference between the radii of the contact surfaces on the support ring (38) and the support disk (39).

The gear box (1) described above represents only one possible embodiment . Since it is a gear box similar to an oil net, other designs are also conceivable . The gear box (1) can also be operated in reverse, ie the drive is connected to the gear box output shaft C 4 3 ) and the gear box input shaft (3) is subjected to a load. It is possible to connect the support (33) to the gear box (3) and instead of ^{rotating the} support ^body C 7 ), but &eegr;a;: h as before axial '-' H ' s &zgr;' 1 eb I "' h, ar, &zgr; lj &ogr;·" d r er . It ■ st ajch r-. ■ c ' -t -3 i ~, ~. ° :. : '"j&zgr; :,-j " , ". ■ e 3 . ■.;'r> c ^ ^; 5 = ' 3 V / ·('»■'?:;; ^ - &zgr; ^ -. r ^&Lgr; . ' e '

Of course, this can also be done the other way round, so that the support body (7) is coupled to the gearbox output and the support ring (38) is coupled to the gearbox input.

It is also conceivable that the planetary cage (15) is connected to the gearbox input and either the support ring (38) or the support disk (39) is coupled to the gearbox output with a non-rotatable support body (7). Of course, this can also be the other way round.

Finally, it is not absolutely necessary that one of the support bodies, i.e. either the support body (7) or the support ring (38) or the support disk (39), is arranged in a rotationally fixed manner. It is also conceivable that the support body which is rotationally fixed in the embodiment shown, namely the support ring (38), also carries out a rotational movement, for example, is connected to the transmission input shaft (3) via a gear. This is also not necessary if the planetary cage (15) is held in a rotationally fixed manner. In this case, the support ring (38), if it is not connected to the transmission input or output, must be mounted so that it can rotate freely.

Claims (1)

Expectations: Hans Ströter KG Gearbox Construction Krefelder Str. 117,, D- 4QOO Düsseldorf 11 Stepless gear box 1. Continuously variable transmission with the following features: (a) the transmission has a transmission input and a transmission output; (b) a planet carrier with planetary bodies mounted therein is rotatably mounted in the gearbox; (c) the planetary bodies each rest on three supporting bodies with running surfaces concentric with the planet carrier; (d) at least one of the support bodies is arranged to be axially displaceable in order to adjust the transmission ratio ; (e) an actuating device is provided for its axial displacement; (f) at least one, in particular two of the support bodies is or are rotatably mounted and connected to the transmission input or output; ^{characterized} by the following features: (g) the planetary bodies (2^>, 25) have a lateral surface (32, 33) and end faces (34, 35, 36, 37); (h) a support body (7, 38, 39) rests on the end faces (34, 35, 36, 37) on one side of the axis of rotation (26, 27) of the planetary bodies (24, 25); (i) on the outer surface (32, 33) of each planetary body (24, 25) there is a third supporting body (C 7) on the other side of the axis of rotation (22, 27); (j) the planetary bodies (24, 25) are pivotably mounted with their axes of rotation (26, 27") in a plane passing through these and the three contact surfaces of the support bodies (7, 38, 39); (k) End faces (34, 35, 36, 37) and dumbbell surface (32, 33) of each planetary body (24, 25) are shaped in such a way that by axial displacement of the displaceable support body (7) a pivoting of the planetary bodies (24, 25) can be effected while maintaining the contact with the support bodies (7, 38, 39). 2. Transmission according to claim 1, characterized in that the axes of rotation (26, 27) of the planetary bodies (24, 25) are directed essentially axially and are each pivotable about a pivot axis lying in the circumferential direction of the rotational movement c '.· :■ planet carrier (15, 16, ¹⁷ ). 3. Transmission according to claim 2, 1 &igr; &bull;&igr;/&iacgr; e ^r S ?■".'] j ·~ rinense't ig a: <? , 53/ a G *? t r i &rgr;&ogr;βgr;&udigr;&Lgr;;&EEgr; A &eegr; -. &Ggr;&igr; r &igr; j r. h 2 &eegr; d ? r 3 . dad &ugr; rc" geke' ';e &igr; honor! that s ■ c ■*: d ■ e running surfaces de' on the forehead*.acne &eegr; (34, 35, 36, 37) de' planetary body C 2 4, 25) adjacent supporting body C 5 8 , 39) are axially opposite. 5 . be t just after a.-; the speech characterized in that the mantles (32, 33) of the planetary bodies (24, 25) have an evisceration (30, 31) for the attachment of the support ^body (7). 6. Gearbox according to Ansorucn 5, characterized in ^that the running ^surface of the support body (7) is ^rounded . 7. Gearbox according to one of claims 6 to 9, characterized in that the planetary bodies (24, 25) are pivotably mounted at one end on the planetary carrier (15, 16). S. ^Gear according to claim (7), characterized in that the planetary bodies (24, 25) are pivotably mounted at the other end in guide slots (28, 29) extending in the plane of the planetary gear. 9. Transmission according to one of claims 1 to 5, characterized in that the planetary bodies (24, 25) are rotatably mounted on rotationally fixed axle bolts (26, -U- IG. Get'ieoe to pine." the art. proverbs 1 to 9, characterized by the fact that the support body (7) resting on the shells (32, 33) of the planetary bodies (24, 25) is axially &ngr; first-thrust L i ge I dy -■ ^r t. 11. Device according to one of claims 1 to 10, characterized in that one of the support bodies (38) resting on the end faces (34, 36) of the planetary bodies (24, 25) is arranged in a rotationally fixed manner. 12. Transmission according to claim 1G or 11, characterized in that the support body (7) resting against the outer shells (32, 33) of the planetary bodies (24, 25) is connected to the transmission input (3) and the non-rotatably arranged support body (38) is arranged on the input side.