RU2431065C1 - Joint of equal angular velocities - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: cardan joint of equal angular velocities of torque consists of driving link (1) connected to first cross piece (3) by means of joint axis (7) perpendicular to rotation axis (5) of link (1), of driven link (2) connected to second cross piece (4) with joint axis (8) perpendicular to rotation axis (6) of link (2) so, that joint axes (7, 8) of links (1, 2) are positioned in same plane. Link (1) is tied with link (2); also, links (1, 2) rotate at different angular velocities. The joint imposes additional bind on cross pieces (3, 4) and also adjusts and maintains rotation of cross pieces (3, 4) around axis - bisector of angle (€) of mutual deviation from coaxiality of links (1, 2) by means of additional dynamic bind from centrifugal forces effecting cross pieces (3, 4) and binds of joint connections along axes (7, 8, 10) of all four movable links (1, 2, 3 and 4) united in a five-link spherical mechanism including cross-pieces (3, 4) each having a pair of orifices and a pair of journals. Cross pieces (3, 4) are interconnected along common axis (10) perpendicular to axis (7) of orifices of driving link (1) and to axis (8) of journals (13) of link (2). Link (2) is made T-like in form of a rod with journals (13) of joint connection with cross piece (4).

EFFECT: increased angle of mutual deviation of driving and driven links, simplification of device and reduced length of cardan joint of equal angular velocities.

2 cl, 11 dwg

Description

The invention relates to nodes of agricultural, transport and other machines.

Known hinges of equal angular velocities, for example: ball [1] p. 46 ... 48, fig. 11.39 ... 41; DE 2461298, 1976.06.16; cam [2] p. 152, 153, fig. 116; double hinges without centering the forks [3] Fig. 51 on the tab to p.136, (this is actually a short cardan shaft) and the same with the centering device of the forks for positioning equal (practically for approximately equal) angles between the drive (driven) and intermediate shaft cardan shaft [1] p. 45, 46, fig. 11.37a).

The lack of ball joints in large contact stresses even at low torques. In cam joints, the torque is transmitted through kinematic slip pairs, which have high heating due to the reduced efficiency [2] p. 153, Fig. 116. For double hinges without centering the forks, cam and some ball, an external axis of rotation is also necessary [2] p. 152, 153, fig. 116, which limits the versatility of use. For example, such hinges are not suitable for the power shaft of a trailed agricultural machine. A common drawback of the known hinges of equal angular velocities is also the limited angle of deviation of the driven link from the driving link by only 15 ... 40 degrees.

Known cardan joint of equal angular velocities of torque, containing a driving link connected to the first crosspiece by a hinge axis perpendicular to the axis of rotation of the driving link, a driven link connected to the second crosspiece by a hinge axis perpendicular to the axis of rotation of the driven link, so that the hinged axes of the driving and driven link located in the same plane, and the leading link is connected to the driven link with the possibility of rotation of the driving and driven links with equal angular velocities, for example double arnir [1] p.45, 46, and ris.11.37) - prototype.

Its disadvantage is the angle of mutual deviation of the leading and driven links, limited to 40 degrees, in increased complexity (8 needle bearings and a device for centering the cross pieces).

The objective and the technical result are to increase the angle of mutual deviation of the driving and driven units, simplifying the device and reducing the length of the universal joint of equal angular velocities.

1. The invention is a cardan joint of equal angular velocities of torque containing a driving link connected to the first crosspiece by a hinge axis perpendicular to the axis of rotation of the driving link, a driven link connected to the second crosspiece by a hinge axis perpendicular to the axis of rotation of the driven link, so that the hinge axes the leading and driven links are located in the same plane, and the leading link is connected to the driven link with the possibility of rotation of the driving and driven links with equal angular speeds, different which contains the possibility of imposing an additional dynamic connection on the first and second crosses (3 and 4), as well as exposing and holding the rotation of the crosses (3 and 4) around the axis — the bisector (11) of the angle (9) of mutual deviation from the alignment of the leading and driven links (1 and 2) through additional dynamic communication from centrifugal forces acting on the cross (3 and 4), and the joints of the swivel joints along the axes (7, 8, 10) of only four movable links (1, 2, 3 and 4) united in a five-link spherical mechanism, including the first and second crosspieces (3 and 4), each of which has a pair of holes and a pair of pins, the first and second crosspieces (3 and 4) mutually connected along a common axis (10) perpendicular to the axis (7) of the holes of the driving link (1) and to axis (8) of the trunnions (13) of the driven link (2), while the driven link (2) is made T-shaped in the form of a rod with trunnions (13) of a hinged connection with the second cross (4).

2. The invention also lies in the fact that the bearing of each hinge is sealed with a reinforced cuff, so that the sealing edge of the reinforced cuff is adjacent to the outer race of the bearing.

Due to such signs, the angle of deviation from alignment is greater than that of the analogue, the universal joint of equal angular velocities (hereinafter referred to as the RUS joint) contains fewer bearings than the analogue, the crosses are self-centering precisely, the calculated torque and durability are greater than those of the Hook joint with the same dimensions. The hinge RUS is reversible. A leading link can be a slave and vice versa.

The RUS joint has been arranged, for example, with the following calculated parameters: the rotation of the driving (driven) links is uniform, the speed is N = 1000 rpm, the durability is 90% of the bearing life guarantee L = 1000 hours, the calculated torque is M = 70 kgm with a joint angle of 0 to 20 degrees, dimensions: length G = 280 mm, the largest diameter of rotation D = 155 mm, as follows.

Figure 1 shows the hinge of the RUS in the position of mutual deviation from the alignment of the axes of rotation of the driving and driven links (hereinafter the angle ∈ of the hinge) by ∈ = 60 degrees. The dotted line shows the position of the shaft end onto which the leading (driven) link of the RUS joint is mounted.

Figure 2 shows a graph of the estimated torque depending on the angle of the hinge RUS (upper solid line) and cardan joint KSh 630 [4] p. 18 (lower solid line), with an estimated durability of 1000 hours. The dashed line is the estimated torque of the KSh 630 hinge with the estimated durability according to [4] p. 36 (about 700 hours). The calculation is performed according to the formula from [4] p.36.

Figure 3 shows the hinge RUS after rotation of the leading link 90 degrees around the axis of rotation.

Figure 4 on a reduced scale shows a variant of the hinge RUS, in which the consoles forks of the leading (driven) link are modified into a cup with a cylindrical and spherical thin wall.

In Fig.5 - the same as in Fig.4, but after the rotation of the leading link 90 degrees around the axis of rotation.

Figure 6 shows the first cross with a seal collar, a pair of pins and a pair of holes for needle bearings of articulated joints with mating links.

In Fig.7 shows a second cross with a cuff seal, a pair of pins, a pair of holes for needle bearings of swivel joints, with one bearing shown.

In Fig.8 shows a cage for a needle bearing, for example 941/25 GOST 4060-78.

Figure 9 shows the cage for a needle bearing, for example 941/20 GOST 4060-78.

Figure 10 shows the leading (slave) link with a pair of holes for bearings swivel with the first cross.

In Fig.11 shows a driven (leading) link assembly with 2 seal cuffs and pins for swiveling with a second cross.

Symbols in figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11:

1 - link hinge RUS, for example, the leading (slave) link, (hereinafter referred to as the link).

2 - link hinge RUS, for example, a driven (leading) link, (hereinafter - link),

3 - the first cross (hereinafter - the cross),

4 - the second cross (hereinafter - the cross),

5 - axis of rotation of link 1 (hereinafter - the axis),

6 - axis of rotation of link 2 (hereinafter - the axis),

7 - the axis of the articulation of link 1 with the cross 3 (hereinafter - the axis),

8 - the axis of the articulation of link 2 with the cross 4 (hereinafter - the axis),

9 - the angle of mutual deviation from the alignment of the axis 5 and axis 6 (hereinafter - the angle ∈),

10 - the axis of the swivel of the crosses 3 and 4, perpendicular to the axes 7 and 8 (hereinafter - the axis),

11 - instantaneous axis of rotation of the crosses 3 and 4 - bisector of angle ∈ (hereinafter - the axis),

12 - axle axis 7 with a threaded hole for the puller when disassembling the hinge RUS (hereinafter - the trunnion),

13 - axle axis 8 (hereinafter - the axle),

14 - axle axis 10 with a threaded hole for the puller when disassembling the hinge RUS (hereinafter - the axle),

15 - a cage intended for installation in it of a needle bearing of a hinge along axis 7 and having a belt of reduced diameter for the sealing edge of the cuff (hereinafter referred to as the cage),

16 - end cap of the holder 15 (hereinafter - the plug),

17 - a cage designed to install in it a needle bearing of the hinge along the axis 8 and having a belt of reduced diameter for the sealing edge of the cuff (hereinafter - the cage),

18 - end cap of the holder 17 (hereinafter - the plug),

19 - cage, designed to install in it a needle bearing of the hinge along the axis 10 and having a belt of reduced diameter for the sealing edge of the cuff (hereinafter - the cage),

20 - end cap of the clip 19 (hereinafter - the plug).

Thrust spring rings internal flat concentric, for example, according to GOST 13941-86:

21 - ring A32.60C2A.Kd.6hr (hereinafter - the ring),

22 - ring A38.60C2A.Kd.6hr (hereinafter - the ring),

Reinforced rubber cuffs for shafts, for example, according to GOST 8752-79:

23 - cuff 1.1 - 30x42 - 1/4 (hereinafter - the cuff),

24 - cuff 1.1 - 36x48 - 1/2 (hereinafter - the cuff).

Needle roller bearings with one outer stamped ring, for example, according to GOST 4060-78:

25 - bearing 941/20 on axis 7 (hereinafter referred to as the bearing); between the middle of the bearings size B = 12.90 cm,

26 - bearing 943/25 on axis 8 (hereinafter referred to as the bearing); between the middle of the bearings size B = 5.32 cm,

27 - bearing 942/25 on the axis 10 (hereinafter referred to as the bearing); between the middle of the bearings, size B = 10.10 cm.

Structurally, the hinge RUS represents such a modification of the prototype [1], p.45, 46, Fig. 11.37 a) (that is, a short driveshaft) that its length between the poles of the hinges is zero, and the crosses 3 and 4 of the hinges are connected directly to each other the hinge axis 10. Therefore, the hinge RUS is a five-link spherical mechanism, contains one movable link and one kinematic pair of the fifth class less than the driveshaft with Hook joints, and one more kinematic pair of the second class less than the prototype [1], p. 46, fig. 11.37 a). One link, for example, the leading (driven) link 1, is made in the form of a Hook hinge fork for bearings 25 with a cage 15 and a plug 16 of a swivel joint with the spider 3 along axis 7 (Figs. 1, 9 and 10). In another embodiment of the console, the forks of this link are modified into a cup with a spherical and cylindrical thin wall thickened around the holes for bearings 25 with a cage 15 and a plug 16 of the swivel joint with the spider 3 along axis 7 (Figs. 4, 5 and 9). Another link, for example, the driven (leading) link 2, is made T-shaped in the form of a rod with pins (Figs. 1, 3, 4, 5, 8, and 11) for bearings 26 with a cage 17 and a plug 18 of a swivel joint with a cross 4 according to axis 8. A hub is welded to this rod to connect to the shaft. The rod between the trunnions and the hub has a rectangular section of variable width and thickness that is equally strong along its length (Fig. 11). In the given example of the RUS hinge for a torque of 70 kgm, the dimensions of the rectangular section of the link rod 2 are calculated according to the formula (34.6) and Table 1.6 [5], p.208, as for a driveshaft for receiving power of an agricultural machine. Such a cardan shaft is assembled from two hinges of the RUS and the intermediate shaft so that the intermediate (including telescopic) shaft is located between the hinges of the RUS and is welded to the rods of the T-shaped links 2 instead of the hubs. In this case, the maximum reduced moment was determined by the 3rd hypothesis of strength [6], p.142, for uniform rotation (dynamic coefficient K = 1) of links 2 and 1. Material of link bar 2 and pins 13 of axis 8 Steel 20XHGR, heat treatment: hardening - tempering in oil, hardness HRC 50, permissible torsion stress 3800 kg / cm [7], p. 91, trunnions cemented. Peeling steel 20KhNGR [8], p.64, table 78 and welded [8], p.68, table 88.

Landing diameters for cuffs 23 and 24 have an annular groove in the form of a right triangle in accordance with GOST 8752-79, p.30, Fig. 3. The cuffs are installed before installing the pins 12, 13, 14.

The pins 12 are installed in the holes of the crosspiece 3 along the axis 7 through the holes in the link 1. The pins 13 are installed in the hole of the link 2 along the axis 8 through the holes in the crosspiece 4. The pins 14 are installed in the holes of the crosspiece 4 along the axis 10 through the holes in the crosspiece 3. Installation of pins 12, 13 and 14 are hydraulically pressed to fit with a guaranteed interference fit, calculated similarly to the keyless connection to the shaft according to [9], pp. 423 ... 434.

A cage 15 with a bearing 25 is installed in the holes of the link 1 along the axis 7, closed with a plug 16 and fixed with a ring 21. A cage 19 with a bearing 27 is installed in the holes of a crosspiece 3 with an axis 10, closed with a plug 20 and fixed with a ring 22. Adjoining to the rings 21 and 22 the gaps are covered with sealant, for example, UT-34 [10], p.291.

The plug 18 is soldered to the cage 17, the bearing 26 is inserted and installed by hydraulic pressing into the holes of the crosspiece 4 along axis 8 with a guaranteed tightness, calculated similarly to the keyless connection to the shaft according to [9], p. 423 ... 434.

In mass production, the needle bearing ring and cage are made with one piece.

Work. The degree of mobility of the hinge of the RUS - spherical mechanism is determined by the formula (3.5) of Chebyshev-Artobolevsky [11], p.76, and the additional connection of its links with the geometric dependence (11.8) [11], p.251, which becomes undefined for an angle ∈ = 0 , as well as at two points around the circle every 180 degrees of rotation of link 1 (2).

However, at an angle ∈ = 0, crosses 3 and 4 are exposed and held by centrifugal force so that their axes 7, 8 and 10 rotate in a plane perpendicular to the axes 5 and 6 coinciding, even if the crosses 3 and 4 were in another before rotation position. That is, by rotating the hinge RUS at an angle ∈ = 0, links 3 and 4 impose an additional dynamic connection. Therefore, all links of the RUS hinge have only one degree of mobility even at an angle ∈ = 0.

If the angle C is not equal to zero, then at two points along the circumference of rotation by the dependence (11.8) an additional connection is not imposed. However, at such a point, the resultant vector of centrifugal rotation forces around the axes 5 and 6, the axis 10 of the joints 3 and 4 are held along the bisector of the angle between the axes 5 and 6 and rotate around this axis 11 - the bisector of the angle ∈ (Fig. 3). This axis divides the angle ∈ into two exactly equal parts, since the component vectors are equal in magnitude and symmetric with respect to the resultant vector. That is, by rotating the hinge RUS on links 3 and 4 impose an additional dynamic connection, which keep the crosses 3 and 4 in an unambiguous position when they pass the mentioned points. Therefore, all links of the RUS hinge have only one degree of mobility at the points mentioned, even if before the start of rotation of the cross 3 and 4 were in a different position.

This means that the leading and driven links of the RUS hinge are rotated in the same way as the same links of the driveshaft with Hook hinges lying in the same plane with coaxial forks, with equal hinge angles.

The driveshaft, consisting of two hinges RUS and the intermediate shaft, the driven and intermediate shafts rotate synchronously with the drive shaft at any possible angles between these shafts and a total angle of 2∈ to 120 degrees or more between the drive and driven shafts, as well as at any angle between the extreme links of the hinges RUS propeller shaft.

So, the constant-velocity joint according to the invention (RUS joint) has a maximum angle of deviation from alignment (joint angle) greater than that of analogues, contains fewer bearings than the prototype, the calculated torque and durability are greater than those of the Hook joint with the same dimensions . The hinge RUS is reversible - the leading link can be a slave and vice versa.

It is also possible to use such a joint of equal angular velocities as part of the propeller shaft for conditions under which propeller shafts with Hook joints are not intended.

Bibliography:

1. B.C. Polyakov et al. Handbook of couplings. 2nd ed., Rev. and add. - L .: Mechanical Engineering, 1979, 344 p.

2. Automobile: Design fundamentals: A textbook for high schools with a degree in Automobiles and Automotive Economy / NN Vishnyakov et al. - 2nd ed., Rev. and add. - M.: Mechanical Engineering, 1986, - 304 p.

3. Tractors T-40 and T40A. Instructions for care and maintenance. Ed. B.E. Arkhangelsky, 1968, 226 p.

4. Cardan joints for agricultural machinery. RTM-A23.2.051-83. M .: VISKHOM, 36 p.

5. Darkov A.V., Spiro G.S. Strength of materials. Ed. 3rd M., "Higher School", 1969, 734 pp.

6. Reference designer agricultural machines. Volume 1, ed. A.B.Krasnichenko. State scientific and technical publishing house of engineering literature. M .: 1960, 656 p.

7. V.I. Anuryev. Reference designer mechanical engineer. Volume 1. Ed. 6th redesigned, and augmented. M .: Mechanical Engineering, 1982, 736 p.

8. Zhuravlev V.N., Nikolaev O.I. Engineering steel. Directory. Ed. 3rd, rev. and add. - M.: Mechanical Engineering, 1981. - 391 p.

9. Design of mechanical gears. S.A. Chernavsky et al. - M.: Mechanical Engineering, 1984. - 560 p.

10. Engineering materials: A quick reference / V.M. Raskatov et al. - 3rd ed., Revised. and add. - M.: Mechanical Engineering, 1980, 511 p.

11. I.I. Artobolevsky. Theory of mechanisms. Ed. 2nd fix M .: Publishing house "Science". The main edition of the physical and mathematical literature. 1962, 719 p.

Claims (2)

1. A cardan joint of equal angular velocities of torque containing a driving link (1) connected to the first crosspiece (3) by a hinge axis (7) perpendicular to the axis (5) of rotation of the driving link (1), the driven link (2) connected to the second cross (4) with a hinge axis (8) perpendicular to the axis (6) of rotation of the driven link (2), so that the hinged axes (7, 8) of the driving and driven links (1, 2) are located in the same plane, and the leading link (1) is connected with the driven link (2) with the possibility of rotation of the leading and driven links (1, 2) with equal angular speeds, characterized in that it is made with the ability to impose an additional connection on the first and second crosses (3, 4), and also to expose and hold the rotation of the crosses (3, 4) around the axis - bisector (11) of the angle (C) of mutual deviation from the alignment of the leading and driven links (1, 2) through additional dynamic communication from the centrifugal forces acting on the crosses (3, 4), and the joints of the joints along the axes (7, 8 and 10) of all four moving links (1, 2, 3 and 4) combined into a five-link spherical mechanism, including the first and I cross the joints (3, 4), each of which has a pair of holes and a pair of pins, the first and second crosses (3, 4) are mutually connected along a common axis (10) perpendicular to the axis (7) of the holes of the driving link (1) and to the axis (8) of the trunnions (13) of the driven link (2), while the driven link (2) is made T-shaped in the form of a rod with trunnions (13) of a hinged connection with the second cross (4). 2. The universal joint according to claim 1, characterized in that the bearing of each articulated joint is sealed with a sleeve so that the sealing edge of the reinforced sleeve is adjacent to the outer race of the bearing.

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