DE9411086U1 - Gears with asymmetrical teeth - Google Patents

Description

Description

The invention relates to gears with asymmetrical teeth, suitable for direct and indirect gear-like pairing for the purpose of power transmission in both directions of rotation, in a tooth shape rounded at the head, flank and root transitions for reduction / transmission gears, rotary piston machines as compressors, pumps and motors as well as other areas of application suitable for gears, whereby the direct power transmission by sliding of the individual teeth belonging to the driving gear, as well as the indirect power transmission by sliding of the individual, engaging machine elements, extends from the rounding of the tooth head of the respective teeth belonging to the driven gear over their entire flanks to the roundings on the tooth root and vice versa, the tooth heads of partner gears roll on the deepest gap of the respective partner gear, whose asymmetrical teeth are curved, whose tooth gaps with the tooth flank contours correspond to the rolling processes with opposite The sense of curvature at the point of engagement corresponds to the meshing and disengaging partner teeth or to other parts suitable for working with gears and the dynamic contact pattern, the dynamic lubrication and the noise damping are improved.

Various asymmetrical tooth shapes are known for gears that have a variety of curvatures.

In the case of tools for machining, however, neither their purpose nor their application goals affect the invention. Asymmetrical, even curved tooth shapes are also known in gears, whereby parts that periodically hook into tooth gaps, mostly interrupting the running, determine the sequence of a control system that is to be made uniform. A wide variety of tooth shapes have been used here. However, here too, no pairings of gears with asymmetrical, curved teeth have been made, which would have the aim of transmitting power by sliding from the tooth tip over the tooth flanks to the base of the gap when the teeth mesh with opposite curvatures of the partner teeth at the meshing point, let alone during rolling processes in both directions of rotation with intensive, mutual contact.

of more than one pair of teeth. "** "· · Circumstances are also known in which such gears continue to be used, the teeth of which often develop into asymmetrical teeth very quickly due to one-sided flank and tooth root wear in conveyors for materials with abrasive components. These can only be operated in continuous operation without load peaks. In reversing operation, accidents in the combing process and in particular tooth breakage due to cross-sectional weakening inevitably occur. 10

According to the teaching of the invention, such problems are not to be feared with gears of the type described above.

The invention is based on the object of creating gears of the type described at the beginning, which in a simple manner and thus better than with the previously usual gear geometry for reduction / transmission gears, enable intensive, long-lasting, sliding power transmission from tooth to partner tooth in both directions of rotation, without having to forego the usual fine subdivision of the respective pitch circle and determination by the module and without having to use complex helical, double helical, arrow or other improvement measures for various types of gearing,

for traction/thrust means, safe conditions are provided from the engagement of the teeth to the secure installation of articulated parts of flexible/quasi-flexible traction/thrust means and technically flawless operation with meshing and disengaging in both directions of rotation and by compensating the pitch difference of the thrust/traction means parts that start/run in the meshing/disengaging process compared to the teeth moving on the pitch circle, taking wear into account, but primarily improved, power-transmitting rolling processes with sliding processes of the partner teeth loaded by high forces among each other over the entire available tooth flank areas from tooth tip to tooth root in both directions of rotation without high surface pressures, if possible with additional hydraulic padding of the partner teeth at the point of engagement, going beyond the dynamic lubrication, between each other, especially required for rotary piston machines.

achieve better lubrication of the gear faces compared to adjacent bushings or directly adjacent front flanks of the housing

as well as for the operation of rotary piston machines, larger volumes of the tooth gaps and a smaller volume share of the teeth for the purpose of conveying media, but also larger effective surfaces of the teeth during motor operation, increased sealing values of the teeth among each other in the engagement point and of the tooth heads against the surrounding housing inner walls, thus reducing overall gap losses.

The invention solves this problem in the case of gears of this type by adapting the structure of the individual tooth cross-section from the tooth base to the tooth tip to the development of the bending stress from the first contact of the partner teeth until they leave the tooth flank of the partner tooth by proportionally increasing the cross-section from the tooth tip to the tooth base, the individual tooth is aligned at a skewer angle to the gear wheel radius, the individual tooth is curved in itself and designed with generous rounding radii, the gap width and contour of which are adapted to the movement contour of the partner teeth, and the gears to be paired are arranged in such a way that the partner teeth show opposite curvature at the point of engagement.

The result of these measures of the invention is that rolling processes of gears with asymmetrical, curved teeth in direct pairings with similar gears to form wheel sets are technically safe and collision-free for partner teeth with each other in both directions of rotation and that when such gears are indirectly paired via traction/thrust means, early, long-lasting and power-transmitting engagement of the teeth is ensured by means of collars in the direction of rotation of the tooth flank opposite the tooth tip to the tooth root, technically flawless and without the risk of collision with or with meshing or disengaging parts. When the direction of rotation of such gears is reversed and clearly opposite running direction of the traction/thrust means

The above-mentioned circumstances are taken into account by the generous rounding of the tooth heads, which takes on the load of the respective machine element from the first contact in the meshing process, and also compensates for the difference in pitch when sliding over the front flank of the individual tooth, which is inclined more flatly than the rear flank in this case, until it rests securely in the roundings on the tooth base, thus ensuring that the technically flawless pulling/pushing process takes place in the interaction of such gears with pulling/pushing devices.

Further advantageous embodiments of the invention are listed below. The invention provides that the tooth tip has a wide area on the tip circle thanks to the same direction of curvature of the tooth flanks, which is better suited to reducing gap losses and thus increasing efficiency when using such gears in rotary piston machines than narrow sealing surfaces or only sealing lines in conventional gearing against the inner wall of the housing. The alternating interaction of the wide tooth tip and the gap base at the point of engagement of the partner gears, whereby actual alternating rolling takes place, also contributes to the tightness of the point of engagement, which increases efficiency through tightness and frequency due to the intensive, sliding contact of the tooth flanks and their generous roundings on the corresponding sliding surfaces of the partner gear resulting from the rolling process.

There is no need to fear mutual blockages of such tooth pairs due to heating, because in every phase of the rolling process the gap width is larger than both the tooth thickness and the space required by a partner tooth, however angled relative to the tooth flanks. According to a proposal of the invention with independent significance, it is provided that in the meshing process, from the first contact of partner teeth, the volume remaining between the teeth of the gaps merging into one another is further reduced by the partner teeth moving towards one another, and lubricant or operating medium carried in the gaps to the point of engagement, regardless of the support points or cross-sections for the mechanical power transmission.

tion is put under high pressure.

This creates pressure pads that support the dynamic lubrication of the engagement point, compensate for the flank play and provide lubrication of the gear faces opposite the sealing and bearing bushes or directly adjacent housing side flanges by means of lubricant / operating medium flowing out from the side of the engagement point, as well as causing considerable damping of the running noise, or rather: allowing this to occur to a lesser extent, because the hydraulic cushioning effect prevents all in all the metallic contact between moving parts and with stationary parts to a greater extent than is possible with dynamic lubrication. When such gears are used in rotary piston machines, sufficient operating medium / lubricant is diverted from the padding to the meshing areas in order to avoid cavitation here. With corresponding gear sets for reduction / transmission gears, the latter statements also apply to high speed ranges.
The advantages of the invention are essentially that it has been possible to increase the number and intensity of the tooth engagement points of partner teeth that are curved in opposite directions at the engagement point, in contrast to the previously used spur gearing, while maintaining the same module, to improve the surface pressure through more generous rounding and highly resilient sliding surfaces, thus improving the contact pattern, lubrication and efficiency of rotary piston machines, and to reduce the noise generated by reduction/transmission gears and rotary piston machines.

Literature sources:

" Dubbel" pocket book for mechanical engineering

F. Sass, Ch. Bouch£ A. Leitner

Springer - Verlag Berlin, Heidelberg, New York 1970 First volume, pages 751 to 795, 834 to 854, Second volume, pages 255 to 261, 538 to 539, 690 to 702, "Hütte" pocket book for industrial engineers Academic Association Hütte, E.V. in Berlin and Dr.-Ing. Hans Rögnitz

Published by Wilhelm Ernst & Sohn, Berlin 1952 Part 1, pages 359 to 386; Part 2, pages 545 to 564, 584 and 585.

In the following, the invention is explained in more detail using drawings which merely represent exemplary embodiments; Fig. 1 shows the schematic side view of one of the gears according to the invention in a detail, from which the contour of an individual tooth and its curvature can be seen, Fig. 2 shows the schematic, perspective view of one of the gears according to the invention, partly in side view, partly in plan view, in detail for pairing with similar gears only as a group of teeth and tooth gaps with wide head surfaces and corresponding gap bases as well as the relative size of the tooth gaps in relation to the slender tooth bodies, Fig. 3 shows the schematic side view of a detail of two pieces of gears according to the invention in mesh with each other, whereby the oppositely directed curvature of partner teeth at the point of engagement with the interaction of tooth heads, flanks and gap bases in the meshing and disengaging process, the number of contact points of several partner teeth meshing and disengaging, the size of the flank contact surfaces of partner teeth, the size of Tooth head and gap base contact surfaces and overall the intensity of the power-transmitting sliding of partner teeth against each other on their flanks and their sealing with each other in the event of volume changes between partner teeth and gaps in the rolling process become clear, but also how the meshing and meshing areas are shown collision-free for the partner teeth with each other, Fig.4 shows the schematic cross section through a rotary piston machine with gears used according to the invention, whereby in addition to the sealing of the partner teeth at the point of engagement, the wide head surface, equipped with the radius RK, seals intensively against the housing inner wall, equipped with the radius R P/MG.

Fig.5 shows the schematic side view of a gear according to the invention in engagement with a traction device as part of a conveyor system, whereby the compensation of the pitch difference between the straight-line traction device parts and the asymmetrical, curved teeth running around the pitch circle becomes obvious, Fig.6 shows the schematic side view of a gear according to the invention in engagement with a thrust device, designed as a rack and pinion, whereby the compensation of the pitch difference between the straight-line thrust device parts and the asymmetrical, curved teeth running around the pitch circle is made clear.

Claims (6)

Protection claims 1. Gears with asymmetrical, curved teeth, suitable for power transmission in both directions of rotation with direct and indirect gear-like pairing in a generously rounded design of the tooth shape at the tooth tip, flanks and root transitions for reduction/transmission gears, rotary piston machines, tooth engagement with traction/thrust devices or other areas of use suitable for gears, characterized in that the flank contours of the respective tooth (Fig.l, I) on the gear within the space delimited by the root and tip circle (Fig.l 0 DF and 0 DK) are determined by circular arc pieces (Fig.l, V and H) of different sized circles (Fig.l, RH and RV) with centers (Fig.l, MV and MH) set at different distances (Fig.l, A and B) from the gear center (Fig.J, M), the non-executed, continued circular lines of which outside the overall gear contour in S ( Fig.l, S ), so that the tooth root has a larger cross-section than the tooth head and the tooth body with the radii ( Fig.l, Rl, RlI, RHI and rIV ) of the. Transitional roundings result in an asymmetrical, curved shape of the tooth (Fig.l, I) overall, that the respective tooth (Fig.i, I) within the space delimited by the root and tip circles (Fig.l, 0 DF and 0 DK) is defined in its contour by circular arcs (Fig.l, V and H) of different sizes (Fig.l, RH and RV) with center points (Fig.l, MV and MH) set at different distances (Fig.l, A and B) from the gear center (Fig.l, M) - only similar to a blunt sawtooth - its axis (Fig.l, C) has an angle (Fig.l, qC) with respect to a ray (Fig.l, R) emanating from the gear center (Fig.l, M) and directed through the center (Fig.l, Z) of the tooth, and thus the Tooth itself (Fig.l, I) is curved and an oblique position compared to the otherwise radial alignment/arrangement of gear teeth shows that with the same curvature of both tooth flanks (Fi*}"...!:^ V.i and"iiTO.'ö of the respective tooth ( Fig.l, I ) by determining larger distances between the circular arc pieces that contour them ( Fig.l, V and H ) the tooth tip ( Fig.l, K ) with its broad cross-section has a wide tip or apex surface ( Fig.2, AK ) which, with the transition radii of its generous roundings ( Fig.l, Rl to RlV ) to the flanks ( Fig.l, VI and Hl ), has an advantageous sealing effect or provides a contact and sliding surface both for the rolling process and for sealing at the point of engagement with the partner gear ( Fig.3, I and II ) and with respect to an enclosing housing wall ( Fig.4, W ) on the tip circle as well as for the meshing and unmesh process with a pulling/pushing means ( Fig.5, III , Fig.6, IV ) so that each tooth within the space available on the gear circumference between the tip and root circle ( Fig.l, 0 DK and 0 DF ) for teeth and gaps, thanks to the converging tooth flanks (Fig.l, V ¹ and Hl), it takes up significantly less volume than the associated gap (Fig.l. L) for the partner tooth (Fig.3, IH, nil, Hill _.) _{and thus} the tooth (Fig.l, I) is both curved and designed as a slender body, that for identical or matching gears with different sizes in their determining pitch circle diameters (Fig.l to Fig. 6, 0 DT), tooth heights (Fig.l, ZH) and tooth widths (Fig.l, ZB) of any size are available depending on the intended application, as long as technically safe, collision-free rolling with partner gears allows this, or their pitch (Fig.2, T) in coordination with the pitch of traction/thrust means engaging in the gear contour (Fig.5 and Fig. 6, III and IV) allows this, that the pairing of gears of this type for the rolling process is carried out with partner teeth (Fig.3, II, HI, Uli... _{and II} l _{f &tgr;&tgr;} n _t nlll... _} arranged in oppositely curved manner at the engagement point (Fig. 3, I and II), that the rolling process of such gears among each other ( Fig.3 , Fig.4 ) as well as with pulling and pushing means ( Fig.5, Fig.6 ) over their entire contours from flank 40 ( Fig.l, Vl ), head Fig.l, K )., left. ( Fig.l, Hl ) and Gap base (Fig.l, Fig.2 and Fig.3, G), including all roundings to the continuation at the next tooth and vice versa, that for the pairing of such gears a special toothing geometry is required in order to maintain large apex surfaces (Fig.2, AK), just as in the movement on the pitch circle with (Fig.l and 3, 0 DK) the approach of an asymmetrical partner tooth (Fig.3, I*, iH, iIII ... to II ¹ , H ¹ I, lim ...) by immersing in the contour of the partner gear (Fig.3, I to II) in the area of the available gaps (Fig.3, G in I and II) is alternately represented, in that depending on the direction of rotation both the front flank (Fig.3, V ¹ ) when meshing into the gap (Fig.3, L) requires more space than is known from the usual toothing geometry due to the tooth curvature, on the rear flank (Fig.3, Hl) of the preceding tooth (Fig. 3, III ) of the partner gear { Fig.3, II ) and its corresponding roundings for contact-intensive rolling, just as in the opposite direction of rotation the now front flank ( Fig.3, H^ ) with its cantilevered inclination and its roundings demands its counterparts on the leading and trailing tooth of the partner gear ( Fig.3, III, nil ) due to its space requirements, whereby each tooth flank of the tooth on the partner gear ( Fig.3, II ) slides during power transmission and the power transmission is not limited to the small area of just one tooth contact point, but depending on the flank inclination and rounding on the touching teeth, is alternately taken over by at least two contact points in each phase of the rolling process in both directions of rotation and the contour of the asymmetrical tooth ( Fig.l, I ) with regard to tooth height, width, inclination and roundings ( Fig.l, ZH, ZB, OC, R ¹ to rIV ) to and with the adjacent tooth gaps ( Fig.l to 3,G) in relation to gap width and rounding ( Fig.l and 2, LW and R ¹ to R ¹ V ) is designed so that the respective tooth ( Fig.l, I ) from the tip circle ( Fig.l, 0 DK ) to the root circle ( Fig.l, 0 DF ) has a progressive cross-sectional increase, which effectively counteracts its actual stress due to bending moments in the power transmission , _t that the generous roundings ( Fig.l, R ¹ to RlV**) counteract any notch effect and that the respective tooth (Fig. 1 to 6, I or II) for power transmission to either partner tooth (Fig. 3, II) 5 or traction/thrust means (Fig. 5 and 6, III or IV) has rounded edges which do not allow excessive surface pressures to occur. 2. Gears with asymmetrical, curved teeth, suitable for power transmission in both directions of rotation with direct and indirect gear-like pairing according to claim 1. characterized in that in paired gears (Fig.3, I and II) the respective tooth head (Fig.3, K) engages with interactive power transmission from contact point (Fig.3, 0) to contact point slidingly up to the gap base (Fig.l to 3,G), namely up to the root circle (Fig.l, 0 DF) of the partner gear (Fig.3, II) and vice versa and rolls on or at the root circle (Fig.l to 3, 0 DF) in a technically perfect manner, that the transition radii required for the rolling process (Fig.l R ¹ to R ¹ V) on the tooth tip (Fig.l, K) and tooth root (Fig.l, F) ensure that the forces for driving or driven movement, depending on the operating state, on the front or rear flanks in the direction of rotation (Fig.l and Fig.3, V^ and H ¹ ) of the partner gears (Fig.l and Fig.3, I and II) are taken over in a technically perfect manner in every meshing or meshing situation with more or less large surface areas sliding on one another with low surface pressure, that the tooth root thickness, head thickness and height with the resulting gap size (Fig.2, Fig. 3, ZB, ZK and H as well as Fig.2, WL) for the rolling process with partner teeth which show opposite curvature at the point of engagement are coordinated with one another independently of the module in order to create as much/large a gap volume as possible, insofar as the section modulus of the individual tooth does not exceed this and thus the largest possible delivery volume for compressors and pumps or the largest possible effective surfaces for rotary piston engines are created,
that from the beginning of the meshing engagement of the teeth paired under opposite curvature, the operating or conveying medium is squeezed out between the contact surfaces by forcing it in from the first contact of the tooth tip ( Fig.3, K ) on the flank ( Fig.3, H ¹ ) of the partner tooth and by its further penetration into the gap ( Fig.3, L ) to the bottom of the gap ( Fig.3, G ) by means of continued volume reduction of both tooth gaps ( Fig.3, G ) of the two partner gears ( Fig.3, I and II ) and supports both the dynamic lubrication of all teeth involved among themselves and that of the end faces of such gears with respect to the sealing and bearing bushes or other flange-like parts such as directly adjacent housing side flanges, if not replaced as hydraulic padding, if the operating medium or gas or fluid to be conveyed has neither polarity to the material of the rotary piston machine in question nor other properties of lubricity, that the emission of running noise is dampened, if not eliminated, by the aforementioned cushioning effect, and its components are thus prevented from occurring, and that the noise development is reduced by the sliding of all contact points, lines and surfaces against one another from the first power-transmitting contact of the partner teeth (Fig.3, I ¹ , I ¹ I, I ¹¹¹ ... and III, H ¹ I, IlIII... ) in the rolling process from the tooth tip via the flank to the root (Fig.3, K, V ¹ / Hl to F), including all roundings up to the combing out. 3. Gears with asymmetrical, curved teeth, suitable for power transmission in both directions of rotation in direct or indirect gear-like pairing according to claim 1 and 2 or one of these characterized by that the tooth height (Fig.l, H) is chosen to be arbitrarily large in accordance with the special rolling geometry/development, in particular with the tooth angulation (Fig.l, QC) and depending on the gap width (Fig.2 and 3, WL), tooth root and head width (Fig.l, ZK and ZB) depending on the target specification, without endangering the technically safe, collision-free rolling process of such gears among each other, that for the pairing for the purpose of sub-/translation in case of sub- · different pitch circle diameters or root and tip diameters of the teeth (Fig.2 and 3, I and II) for smaller gears of this type, larger tooth cross-sections with narrower gaps, whereas for larger gears of this type, smaller tooth cross-sections with larger gaps, occurring torques and thus bending stresses are designed accordingly, without thereby affecting the technically safe, flawless rolling process, that the contact pattern is stretched over the entire surface of the flank in such teeth (Fig.l, 2 to 6, V* and H ¹ ), thus showing a dynamic development and thus excluding periodically occurring overloading of the teeth as in narrow, limited contact patterns with the resulting chatter marks, slight martensite formation or even pitting, that after running in such gears of different sizes, thanks to dynamic, sliding power transmission, even with lower manufacturing precision, the close contact is maintained alternately at at least two contact points in each rolling phase with little removal of wear volume, thus meeting the compact design of gears, that the lubrication by conventional lubricants or operating media, regardless of whether with or without the addition of additives, is improved beyond the dynamic lubrication by the proportion of the hydraulic cushioning acting as a result of the volume reduction in the tooth gaps when partner teeth dip into the turned gaps (Fig.3, L and I ¹ , I ¹¹ , I ¹¹¹ ... and II ¹ , II ¹¹ , II ¹¹¹ ... ) and the corresponding squeezing out of the lubricant / operating medium during the rolling process, in that fixed and moving parts remain separate during the rolling process and excessive stress on smaller flank, head and root areas is excluded and that helical, double-helical, herringbone and other meshing and load-bearing behavior-improving measures applied to such gears further enhance the previously mentioned improvements, as mentioned above. 4. Gears with asyramatric^^gacriummt teeth, gee ig- net for power transmission in both directions of rotation with direct or indirect gear-like pairing according to claim 1, 2 and 3 or one of these, characterized in that the contour of the asymmetrical, curved tooth and the adjacent gaps, including their transition roundings (Fig.l, 2 and 3, I, L and R ¹ to R ¹ V) compensates for the pitch difference between straight-line or even curved traction/thrust means compared to the teeth guided on the pitch circle, in particular by their rounding of the transition areas on the tooth head, flanks and root (Fig.l, K, V ¹ , H ¹ and R ¹ to R ^IV ) and by the projection of the tooth head (Fig.l, K) in connection with the projection flank (Fig.l, H*), or, but also vice versa, in the opposite direction of rotation (Fig.5 and Fig.6), that the tooth root on the tooth (Fig. 1,1) is equipped with a significantly larger cross-section than the corresponding tooth center and than the tooth head (Fig.l, K) and thus offers a larger wear volume on the tooth root, in particular due to the generous roundings (Fig.l, R ¹ to R ^IV ) to the gap base (Fig.l, G), the use of which would not result in a significant weakening of the section modulus or an obstructive influence on the contour with regard to the meshing/rolling or combing process for wheel sets or for the cooperation with traction/thrust means in any direction of rotation, that the contour of a respective gear (Fig.l to 3, I) for cooperation with pushing/pulling means through the pronounced rounding of tooth gaps (Fig.l, R ¹ to R ^IV ) to the gap base (Fig.l, G) optimal sliding contact of the individual parts of the pulling means which dip into the gear contour (Fig.l, I) or detach themselves from it {Fig. 5, III ), thereby also equalising the forces in both partners involved in the power transmission and thus weakening the polygon effect, that the tooth on the gear wheel (Fig. 6, I ) can have a significantly lower tooth height than is required for conventional rack and pinion gears, because thanks to the wide Tooth head surface, tooth inclination and - depending on the direction of travel - engaging forward/rearward flanks (Fig.l and 2, AK, (X and V / H) this intensive system offers for engaging drive shaft parts, especially at the gap base (Fig.l, G and Fig.6, G) and that the gear contour with the inherently strong tooth (Fig.l, I) makes a precautionary support surface for meshing engagement of pull/push means with strong wear due to abrasive materials superfluous. · · mm