RU133578U1 - TRANSMISSION SIDE-CONICAL PLANETARY - Google Patents

Abstract

Transmission end conical planetary, comprising a housing, coaxially located input and output shafts, a block of bevel gears that perform a precession movement relative to the central axis of the transmission, located between the drive and driven transmission shafts, coupled to several gear crowns, one of which may be inhibited, and the other is located on the driven shaft, characterized in that the transmission combines gear pairs with a small difference in the number of teeth, a large number of simultaneously contacting teeth at a large angle of transmission to the block of gear bevel gears, which performs a precession movement located between the driven and driving shafts and separated from them, on one side by a ball bearing lying on the axis of the coaxially located input and output shafts, at which the vertices of the pitch cones of all gears converge crowns and all transmission axes, on the other hand, by a rolling bearing, through which the inclined part of the drive shaft acts on the block of bevel gears.

Description

The utility model relates to mechanical engineering, namely to mechanical gears with gearing.

Similar planetary gears are known in which the drive shaft communicates with the help of a cam, an eccentric or an inclined washer to the entire gear, individual parts of the gear (gears with a flexible element, wave) or individual teeth located in the grooves of the rotor and interacting with the stationary end gear. For example, the Planetary Gearbox is known (ed. St. No. 132940 in class 47, 7, published in the "Bulletin of Inventions" No. 20 for 1960). In this reducer, the role of the swinging block of bevel gears is performed by movable teeth.

The disadvantage of this planetary gearbox is that the use of the displacement of the oscillating gear relative to the stationary gear being meshed with it complicates the design, increases the number of parts used, and then the material consumption and cost of the product. A significant drawback is the increase in the size of such gears. It is practically impossible to implement the reverse of the output shaft with this analogue with respect to the input-output angular velocity vector.

Analogs can also include “Conical planetary end reducer: innovative solution” // Bulletin of Pacific national university. 2010. No. 2 (17), which is a private technical solution to the issue of using a precessing block of bevel wheels with end engagement for transmitting torque from the engine to the actuator.

The closest transmission prototype can be considered “conical wave transmission” (patent 2145016 ⁽¹³⁾ C1, IPC ⁷ F16H 1/32, published January 27, 2000). The prototype contains a housing, coaxially located input and output shafts, a block of bevel gears performing a precession movement relative to the central axis of the transmission, located between the drive and driven transmission shafts, coupled to several gear crowns, one of which can be inhibited, and the other is located on driven shaft.

However, we note the main disadvantages of the transfer of the prototype:

Increased (in comparison with the proposed utility model) dimensions and insufficient contact strength of the teeth, which limits the load capacity.

The lack of stability and durability of the flexible element in wave transmissions reduces the useful life of the structure and increases the likelihood of failure.

The use in most cases of one pair of end gears, limiting the gear ratio.

The use of non-standard gear rims with a trapezoidal tooth profile (instead of a more technological involute) and a large number of structurally complex special parts that increase the material consumption, the complexity of manufacturing and the cost of construction.

The need to use an oscillator associated with the input shaft for the transmission.

The technical problem, the solution of which the claimed utility model is aimed at, is to create a design that allows transmitting large torque and a large gear ratio at small sizes.

The solution to this problem is achieved by the fact that in the transmission end conical planetary, comprising a housing, coaxially located input and output shafts, a block of bevel gears performing a precession movement relative to the central axis of the transmission, located between the drive and driven transmission shafts, coupled to several gear rings , one of which can be inhibited, and the other is located on the driven shaft, combined the execution of gear pairs with a small difference in the number of teeth, a large number of con actuating teeth at a large angle of transmission to the block of gear bevel gears, which performs a precession movement, located between the driven and driving shafts and separated from them, on the one hand by a ball bearing lying on the axis of the coaxially located input and output shafts at which the vertices of the pitch cones meet of all gear rims and all transmission axes, on the other hand, by a rolling bearing, through which the inclined part of the drive shaft acts on the block of gear conical wheels.

The essence of the utility model is illustrated by the drawings: FIG. 1 (transmission, designed in the form of a drawing of the gearbox in section), FIG. 2 (kinematic diagram), as well as photographs of the prototype of FIGS. 3, 4, 5.

Explanations for the positions of FIG. 1. An inclined washer is rigidly fixed to the drive shaft (1) Н (or the drive shaft has an inclined flat part made at the same time as (1) Н), which is an analogue of the planetary gear carrier. Through the rolling bearing (2), the inclined part of the drive shaft (1) N transmits torque to the block of precessing bevel gears rigidly fastened together - wheels (3) (b) and (4) (c).

The block of bevel gears has two gears b and c (Fig. 2) and with its ball bearing (or by means of a ball) (6) rests on the driven shaft (5) (d).

The block of precessing bevel gears is made in such a way that the vertices of the initial cones of the bevel gears b and c coincide with the center of the ball bearing. Thus, the vertices of all dividing cones of all gears are located in the center of the ball bearing lying on the axis of the coaxially located input and output shafts. At the same point, all transmission axes converge (intersect), figa.

The conical ring gear b is constantly engaged with the ring gear a of the stationary end wheel (7) ( a ), which is the central gear wheel. Wheel a and wheel d (FIG. 1 and FIG. 2) are located on the central axis O _d —O _{H of the} transmission. Wheel b and wheel c are on the transmission axis O'-O (FIG. 2). The O'-O axis intersects the central axis O _d -O _H at O — the center of the ball joint. The O'-O axis makes a precessive motion about the O _d -O _H axis with a frequency equal to the input shaft rotation frequency, constantly crossing the central axis O _d -O _H at point O.

The bevel gear with (with external teeth) is meshed with the bevel gear d (with internal teeth!). Gear d is integral with the driven gear shaft (5) (d) or is mounted and fixed separately on the output shaft.

The transmission housing can be implemented in different ways, for example (Fig. 1), made of two parts: the housing (8) and the flange (9). The drive and driven shafts are mounted on bearings (10).

To obtain the highest gear ratio, the gear rims a and b, as well as the rims c and d, should differ by one tooth.

One pair of engagement gears, for example a and b, may have one module, and another pair of gears, i.e. c and d, is another gear module. It is also possible to implement a gear in which all the teeth have one module.

Any of the pairs of teeth engaged, for example, with and d (or a and b), can have the same number of teeth and in this case play the role of an end gear coupling with a gear ratio of unity. The overall gear ratio of the entire gear is determined by the second pair of engaging wheels.

The total gear ratio of the transmission of the end conical planetary is calculated by the formula:

here z _i is the number of teeth of the corresponding gear wheel.

или

,The “+” sign (plus) is placed in the denominator if

or

,

или

.and put a “-” sign (minus) if

or

.

The transfer works as follows. Options for the implementation of operating modes may be several depending on the requirements for the official termination of the finished product (figure 2, a ):

If the number of teeth of the gears as well as the number of teeth of ring b wheel unit (b-c), then despite the capstan rotation (carrier H), pivot ring b with respect to the pinion and will not, for each tooth rim b will be included in the exact same cavity gear and vice versa. If the number of teeth of the wheels c and d is also equal to each other, then the driven shaft (5) (d) will be completely stationary. The rotation of the drive shaft will only lead to rolling in the teeth in two gear pairs without a relative rotation.

, характеризующие передачу вращательного движения и крутящего момента с ведущего вала на ведомый. В зависимости от соотношений чисел зубьев с и d возможно и реверсивное движение ведомого вала.If the numbers of the teeth of the wheels c and d are not the same, then according to formula (A), the gear ratio

, characterizing the transmission of rotational motion and torque from the drive shaft to the driven one. Depending on the ratios of the numbers of teeth c and d, a reverse movement of the driven shaft is also possible.

If the number of teeth of gear a will differ from the number of teeth of crown b of the conical block, then when the drive shaft (carrier H) rotates, crown b will rotate relative to the stationary gear a in one direction or another.

This relative displacement of the oscillating block of wheels (b-c) is transmitted further to the driven shaft through gears c and d. If the numbers of teeth of the wheels c and d are not the same, it is possible to obtain very large gear ratios (formula (A)) that realize all the advantages of this transmission.

If the number of gear teeth a is not equal to the number of teeth of the ring b, but at the same time the number of teeth of the ring c is equal to the number of teeth of the wheel d, then they (as in the case of paragraph 1), act as an ordinary end coupling or cord joint with a gear ratio of unity. The entire transmission will have a gear ratio determined by the ratio of the number of gear teeth a and b and determined by the formula (A).

If the number of teeth of the rim c differs from the number of teeth of the wheel d and the numbers of teeth of the wheels a and b also differ, then in addition to the main use (item 2.), An alternative (additional) use of the transmission as a differential gearbox is possible. For example, if the wheel brake d, then the corresponding movement of the wheel will come a (Original claim 2 case is inhibited). Similarly, if, with the driving carrier H, we give additional rotation to the wheel a (in the initial case, step 2 it is inhibited), then on the driven shaft, the wheel d, we get the sum of these two movements (differential motion).

Additional specifications and possible design features of the transmission end conical planetary (see figure 2).

Leading (input) and driven (output) shafts are coaxial. The axis O _d —O _H is the central axis of the transmission.

Between the drive and driven shafts are two pairs of bevel gears that are engaged, respectively: ( a- b) and (c-d).

Wheel a is stationary (for example, mounted on the gear case), and wheel d is mounted on the output shaft (or is made integral with it). Wheel b is engaged with wheel a , wheel c with wheel d.

The block of gears (b-c) is located between the drive and driven shafts, and the block of gears (b-c) can freely rotate around an inclined axis (O-O ') and is not rigidly connected to the carrier H of the drive shaft. In turn, the axis (O-O ') as the generatrix of the cone with the vertex in t. O revolves around the central axis of the transmission, the axis (O _d -O _H ), see Fig.

The wheel block (b-c) can freely rotate around an inclined axis (O-O ') due to the rolling bearing (only one (!) Bearing), see figure 1, figure 2, a ' and figure 3-5. located between the carrier N and the block of precessing bevel wheels (b-c).

The proposed conical planetary end gear transmission scheme can be performed with different ratios of tooth numbers ( a ≤ or ≥b) and (c≤ or ≥d), which cannot be performed using cylindrical wheels in planetary or wave transmissions, see Fig. 2, b. With cylindrical wheels, two pairs of gears cannot catch on one side of the central axis of the gearbox, if one wheel of the block of cylindrical wheels with external teeth (for example - c), and the other wheel with internal (for example - b) teeth, see figure 2, b and b '.

In gears with a difference of one or two teeth (with large gear ratios), the radius of the carrier, see figure 2, b, with cylindrical wheels is very small, which causes jamming, and which is not observed in the proposed "transmission end conical planetary".

. Это означает, что электродвигатель, имеющий 1000 об/мин, должен работать более четырнадцати минут, чтобы выходной вал повернулся на один оборот.When the number of teeth: z _a = 121, z _b = 120, z _c = 119, z _d = 120, the total gear ratio of the gearbox will be:

. This means that an electric motor having 1000 rpm must run for more than fourteen minutes so that the output shaft rotates one revolution.

We note as a prerequisite that the considered gear conical planetary cannot be performed with cylindrical wheels, see figure 1, figure 2, b and b '.

10. To make sure the transmission was operational, an experimental version of the gearbox was manufactured with the number of teeth z _a = 67, z _b = 68, z _c = 33, z _d = 34 and, accordingly, with the gear ratio:

.

.

The authors were convinced that such a transfer can be made and successfully and efficiently used in various industries and other fields of activity. Figure 3, 4, 5 shows the elements of a prototype gearbox using a gear conical planetary gear. In domestic manufacturing practice, gearboxes and machines with transmission end conical planetary by the authors are not found.

The proposed transmission scheme, due to its compactness, can find application in the drives of machines and mechanisms in the aircraft industry, in drilling, in hand tools and in other areas of the national economy. The claimed gear end conical planetary can be used wherever it is necessary to transmit a large torque with a large gear ratio for small dimensions of the entire gear between the drive and driven shafts. The transmission scheme can be made as an independent "gear", or be an element of a more complex structure between the engine and the actuator.

Separate engineering solutions brought together here give the transmission both novelty and economic effect in comparison with the prototype:

- an increase in load capacity is achieved by increasing the coefficient of overlap created by the active contact of all the teeth involved in the engagement;

- an increase in the gear ratio of the transmission is obtained due to the possibility of using standard (involute) gearing with a minimum tooth difference between two pairs of adjacent wheels;

- small dimensions of the entire transmission are achieved by the implementation of gear pairs in a block of gear bevel wheels located at an angle to the central axis of the gear and making a precession motion relative to it.

Claims (1)

Transmission end conical planetary, comprising a housing, coaxially located input and output shafts, a block of bevel gears that perform a precession movement relative to the central axis of the transmission, located between the drive and driven transmission shafts, coupled to several gear crowns, one of which may be inhibited, and the other is located on the driven shaft, characterized in that the transmission combines gear pairs with a small difference in the number of teeth, a large number of simultaneously contacting teeth at a large angle of transmission to the block of gear bevel gears, which performs a precession movement located between the driven and driving shafts and separated from them, on one side by a ball bearing lying on the axis of the coaxially located input and output shafts, at which the vertices of the pitch cones of all gears converge crowns and all transmission axes, on the other hand - a rolling bearing, through which the inclined part of the drive shaft acts on the block of gear bevel wheels.

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