JPS6331006B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the transmission or misalignment of rotational motion,
The present invention relates to a device for correcting the relative direction between shafts, and in particular to a single type and double type universal joint assisting device or a variable angle universal joint.

Conventional universal joints generally consist of a central ball or sliding shaft.

A single universal joint consists of at least two pivots. The transmission of motion in this case is not uniform.

However, single joints in modern applications are capable of transmitting motion that is virtually constant due to internal play and is limited to a 6-7 degree crossing angle. When the angular difference is large, it is common to use compound joints that require equal angles and equal orientation of the pivot axes. Under this condition, the transmission between the input shaft and the output shaft is only constant velocity.

When the intersection angle between the two driven axes has exactly the same value with respect to the known origin, the transmission is constant velocity.

In particular, conventional universal joints used in automobiles and power transmission devices are spider-shaped, an example of which is Spicer-Glaenzer.
Joints or ball-type joints such as the Weiss or Rzeppa series, which are joints with three pivots shaped by a ball moving in a curved race. However, the machining of this type of universal joint is difficult and its possibilities are limited with respect to sliding movements and angles between the drive and driven axes.

Another type of conventional universal joint is the so-called Tripode joint, which consists essentially of a shaft, three common points fixed to the shaft, vertical pins, and a cylindrical shape rotatably attached to these pins. or spherical rollers, the finished assembly can slide in a female shaft or so-called tulip. This type of fitting is also fairly difficult to machine and is somewhat brittle.

It is therefore an object of the present invention to have a universal joint that does not have the disadvantages of conventional universal joints, is easy to machine and assemble, has good sliding properties, allows large operating angles (e.g. 20°), and in particular An object of the present invention is to provide a ball type transmission device suitable for the configuration of a constant velocity joint.

To that end, the invention comprises a ball-shaped mechanical transmission between two shaft ends, the front end of the first shaft end being hollowed out to form a female end with an axial housing. It is characterized by being removed.

The cross-section of the housing has at least one side lobe forming a cylindrical rotation passage not perpendicular to the axis of the first shaft end.

Further distinguishing features of the present invention are:
The freedom of the horseshoe arch of the passage lobe, the second shaft end having an extension in the form of at least one male end, the width of which transverse to the axis of the second shaft end cooperating with said shaft end. The reason is that it is smaller than the width of the opening.

The wall of the male end that is remote from the axis of the second shaft end has an axis that is the same diameter as the common passageway of the first shaft end and that is not parallel to the axis of the second shaft end. It is hollowed out near its tip to form a cylindrical rotating recess having a cross section defined by two circular arcs on both diametrical sides.

Yet another feature of the invention is that a coupling ball having a corresponding diameter with the necessary clearance tolerances is inserted into the passageway of the first shaft end and into the recess of the second shaft end so that the coupling ball is free to It is to be maintained.

In one particularly advantageous embodiment with respect to machining, the axis of the cylindrical recess of the male end is perpendicular to the axis of the second shaft end.

in the case of transmissions operating within a relatively high power range, at least two radially separated parallel
It is advantageous to provide a female housing of the first shaft end with a cylindrical passage. The male end of the second shaft end then has a corresponding number of radial elements equal to the number of coupling balls and the number of common passageway-element assemblies.

In this case, the female housing is star-shaped with three equally spaced
It is desirable to have an axial cylindrical rotating passageway with two lobes. And the cross section of the male end is
It is Y-shaped with symmetrical arms spaced 120° apart.

The present invention also relates to a constant velocity compound ball type mechanical transmission device between the ends of two rotary shafts that are not aligned at the same or non-coincident points.

The transmission essentially consists of an intermediate shaft freely disposed between two shaft ends. The single universal joint aid according to the invention is formed by each end of an intermediate shaft, each with a common shaft end.

This type of constant velocity transmission consists of an intermediate shaft suitable for carrying at each end a male or female end of the same type, and each shaft end carrying the end of the intermediate shaft of the same type. With complementary ends.

The ends at both ends of the intermediate shaft are angularly disposed or otherwise aligned with each other in parallel planes. The intermediate shaft can be freely arranged between the two shaft ends, but the displacement of the intermediate shaft is limited by at least one elastic stop member.

Therefore, in the compound transmission according to the invention,
The ends of the two shafts supporting the male and female ends, respectively, are free to slide only in a direction parallel to the axis of one shaft and in a direction at an angle to the axis of the other shaft. The coupling members are rotatably coupled by inserting at least one coupling member into the female end.

In the application of the invention to a transmission device for controlling the relative inclination between two axes, the free end of each radial element of the male end inserted into the female end is connected to each passage of the female end. Slides inside the inner extension part in a direction parallel to the axis,
It is fixed to a push rod that can be moved at will to modify the angle created by the axes of the two shaft ends.

One embodiment of this type of transmission, which is particularly advantageous for robot wrist configurations, consists of three parallel push rods each connected by a link arm to one arm of the male end. .

These and other features of the invention will become more apparent by reference to the following description and accompanying drawings.

The single universal joint assisting device shown in FIGS. 1 to 3 has two shaft ends 1 and 2 arranged at an angle.
Provide a rotating linkage between the

The front end of the first shaft end 1 is connected to the axial housing 3
The housing 3 is hollowed out to form a female end with a
The rotation is parallel to the keyhole forming the cylindrical passage 4 and has a sidelobe-shaped cross section. The side lobes forming the cylindrical channel 4 have a horseshoe-shaped cross section and are defined by radial recesses 40 at their edges.

The second shaft end 2 is provided with an extension in the form of a rectangular male end 5 having a width smaller than the width of a radial recess 40 in which said shaft end can move freely; A radial cylindrical recess 6 having the same diameter as the passage 4 of the shaft 1 is cut into the outer edge of the shaft 1 . The recess 6 has a cross section defined by two circular arcs on both diametrical sides.

The coupling ball 7 has a diameter corresponding to the diameter of the passage 4 and the recess 6 with suitable spacing tolerances and is inserted into the passage 4 and the recess 6 so that it can be inserted between the two shaft ends. It provides a mechanical joint.

The respective positions of the two axes 1 and 2 after half a revolution are indicated by dashed lines in FIG.

Although this type of simplified transmission is not capable of transmitting large amounts of power, it is useful for indexing movements or otherwise simple transmissions, especially for toys. The transmission allows an angular displacement between the respective axes X-X and Y-Y of shafts 1 and 2 to be at least as large as that of conventional transmissions, and a relatively large range of sliding movement between the two shafts. do.

Next, the constant velocity type transmission shown in FIGS. 4 to 8 has two shafts 2 to which rotational motion is substantially transmitted.
Intermediate shaft 50 providing a coupling between 0 and 21
It consists of two ball-type transmissions connected by.

The shafts 20, 21 are both hollowed out to form a female housing consisting of three parallel passages 10, 11, 12 arranged radially in a star shape around an axial cylindrical passage 19; The finished assembly in directional cross section has a cloverleaf shape.

The male end is constituted by an intermediate shaft 50, the cross section of which is Y-shaped with symmetrical arms 13, 14, 15 spaced apart from each other by 120 DEG.

Each arm 13, 14, 15 has a passage 10, 1
1, 12 have the same diameter, and 6 balls inside 1
6, 17, 18, 30, 31 are hollowed out near the tip of each to form two cylindrical housings 24, 25, 26, 27 and 28, 29 in which the housings 6, 17, 18, 30, 31 are fitted.

Said balls provide a coupling between the intermediate shaft 50 and the two shaft ends 20, 21 by sliding within the passages 10, 11, 12 of each of the female ends of the shafts 20, 21.

Two housings 32 and 33 are respectively formed on each end face of the intermediate shaft 50 and receive thrust bearing balls 34 and 35 that abut bearing plates 36 and 37, respectively, and the bearing plates are made elastic by the spring 22 and the rubber block 23. is being pushed.

The above-mentioned device has two shaft ends 20, 21, especially for transmissions having a rotational movement at a constant speed.
Accidental displacement of the intermediate shaft 50 between the two can be prevented.

In many practical applications, the elastic stopper is
It has been proven that this is sufficient. The other stop member is constituted by a bearing surface.

A bellows seal 38 connecting the two shaft ends 20, 21 serves to prevent contamination of the transmission.

This type of constant velocity transmission is capable of coupling shafts with large angular differences and significant deviations from parallel alignment, as well as the transmission of relatively high powers at relatively high speeds of rotation. The transmission has constant velocity at all angles of inclination.

Kinematic studies of this type of compound ball transmission have shown that, unlike conventional universal joint transmissions, the axis of the intermediate shaft 50 is not connected to the two shafts connected by the shaft 50 unless the three shafts are aligned. They do not converge at the same point as the respective axes of the two shaft ends.

In fact, when said axis is tilted and rotated around it, the center of the intermediate shaft 50 describes an ellipse as shown in FIG. Reference numeral 39 in FIG. 9 indicates the point where the axis of the shaft 50 meets the surfaces of the three balls 16, 17, and 18, the curve 40 indicates the locus of the point 39, and the curve 41 indicates the point where the axis of the shaft 50 meets the surfaces of the three balls 16, 17, and 18. ball 16,
17 and 18 are shown.

Next, in FIG. 10, the axis 2 shown in FIG.
0,21 and depending on the angle of inclination in the parallel passages 49, 51, 52 of the three-way protruding female housing hollowed out in the second shaft end 48,
As shown in the case of balls 16, 17, 18 in FIG. 4, their centers are radially displaced about 10 mm from axis 50, and the dimensions of their ellipses are about 2/10 to 3 mm.

The axis of each extension of the three passages 49, 51, 52 includes a push rod 54, 55 each connected by a link arm 56, 57 to an arm 44, 45 of the male end 43, respectively. A housing 53 is formed. Each push rod 54, 55 can constitute a jack piston, the cylinder of which is formed by the associated housing 53.

As a result of the controlled introduction of hydraulic fluid into each jack cylinder, the axis of shaft 42 can be oriented arbitrarily with respect to the axis of shaft 48.

Additionally, each push rod 54, 55 can be actuated by conventional means such as screw jacks, connecting rod devices, etc.

It is clear that the invention is not limited in any way to the embodiments described above with reference to the accompanying drawings. Depending on the intended application, many alternative configurations may occur to those skilled in the art without departing from the scope or spirit of the invention.

Incidentally, the embodiments of the present invention will be described as follows.

(1) an axial housing defining a cylindrical rotation passage whose cross section is not perpendicular to the axis of the first shaft end and having at least one side lobe whose cross section is defined by a horseshoe arch; The first shaft end is hollowed out to form a female end, and the second shaft end has at least one male end-shaped extension extending along the axis of the shaft end. The width of the male end considered to traverse is less than the width of the free opening of the horseshoe arch of the passage lobe cooperating with said end, and the second shaft end has the same diameter as the common passage of the first shaft end. A wall of the male end remote from the axis of the second shaft end is hollowed out near its tip to form a cylindrical rotation recess having an axis not parallel to the axis of the shaft end, and The cross-section of the recess is limited by two diametrically opposite circular arcs, and a coupling ball of corresponding diameter with suitable clearance tolerances is provided in the passage in the first shaft end and in the second shaft end. A ball type transmission device between two shaft ends, characterized in that it is configured to be inserted into a recess and freely held.

(2) The axis of the cylindrical recess of the male end is aligned with the second
The transmission device according to (1) above, which is perpendicular to the axis of the shaft end.

(3) the female housing of said first shaft end comprises at least two radially spaced parallel cylindrical passages, and the male end of said second shaft end comprises a number of coupling balls; Transmission device according to (1) or (2) above, characterized in that it comprises a number of corresponding radial elements equal to the number of common passage element assemblies.

(4) said female housing has an axial cylindrical rotation passage with three equally spaced lobes in the shape of a star, and the cross section of the male end has symmetrical arms with angular spacing of 120°; The transmission device according to (3) above, which is Y-shaped.

(5) An intermediate shaft is freely disposed between the ends of the two shafts, and according to any one of the above (1) to (4), each end of the intermediate shaft is arranged together with the common shaft end. A ball type transmission device formed by two non-aligned points of common or non-coincident points, constant velocity between the ends of the rotating shaft, as a compound ball type, the above (1), (2), (3) or
(4) Transmission device.

(6) said intermediate shaft is adapted to support male or female ends of the same type at each tip;
The transmission device according to (5) above, characterized in that each shaft end is of the same type and has an end that complements the end of the intermediate shaft.

(7) The transmission device according to (5) above, wherein the end portions at the tip of the intermediate shaft are arranged at an angle to each other in parallel planes.

(8) The transmission device according to (5) or (6) above, characterized in that the transmission device comprises at least one elastic stopper member that limits axial displacement of the intermediate shaft.

(9) the free tip of each radial element of the male end inserted into said female end slides in the extension of each passage of the female end in a direction parallel to the axis; The transmission device according to (3) or (4) above, characterized in that the transmission device is fixed to a push rod that can be operated arbitrarily to correct the angle formed by the two axes of the transmission device.

(10) Item (4) or (9) above, particularly suitable for robot wrists, characterized in that the transmission device consists of three parallel push rods each connected to an arm of the male end by a link arm. transmission device.

[Brief explanation of the drawing]

1 is a schematic axial cross-sectional view of a simplified ball-type transmission according to the invention, FIG. 2 is an end view of the female end of the transmission shown in FIG. 1, and FIG. 3 is the same as shown in FIG. 1. 4 is a schematic axial cross-sectional view of a constant-velocity, double-action ball-type transmission according to the invention; FIG. 5 is a schematic cross-sectional view along the line shown in FIG. 4; FIG. 6 is a plan view of the intermediate shaft of the transmission shown in FIG. 4, and FIG. 7 is a plan view of the intermediate shaft shown in FIG. 6.
8 is an end view of the intermediate shaft of FIG. 6 when viewed in the direction of the arrow, and FIG. 9 is a schematic view in a plane located above the line of FIG. 4 in the transmission device. Diagram showing the displacement of the center of the ball, 1st
FIG. 0 is a schematic partial cross-sectional view of a variable angle transmission according to the invention. Description of symbols, 1...First shaft end, 2...Second shaft end, 3...Axial housing, 4...Rotating cylindrical passage, 5...Male end, 6...Radius Directional cylindrical recess, 7... Coupling ball, 10, 1
1, 12... Parallel passage, 13, 14, 15... Arm, 19... Axial cylindrical passage, 20, 21...
...Shaft end, 16, 17, 18, 30, 31... Ball, 24, 25, 26, 27, 28, 29...
Cylindrical housing, 34, 35... Thrust bearing ball, 36, 37... Bearing plate, 38... Bellows seal, 40... Radial recess, 50... Intermediate shaft.

Claims (1)

[Claims] 1. A ball type transmission between the ends of two shafts, the end of the first of the two shafts being provided with a female end extending in the axial direction, the female end having a cross section. an end of the other shaft facing the end of the first shaft, which has an opening in the shape of a horseshoe arch and a cavity extending toward the center in series with the opening, and is provided with the above-mentioned female end. said other shaft is provided with an axially extending male end thereof, said male end of said other shaft being received within said female end of said first shaft; The first shaft of the male end is movable within the cavity of the first shaft, and further includes a horseshoe arch of the female end of the first shaft on the side edge opposite to the horseshoe arch of the female end of the first shaft of the male end. A cylindrical recess having the same diameter as the aperture is provided, and also a horseshoe arched aperture in the female end of the first shaft and a cylindrical recess on the side edge of the male end of the other shaft mentioned above. The above-mentioned ball-type transmission device comprises a ball having approximately the same diameter as the above-mentioned horseshoe-shaped arch opening and is movably held in the space created between the above-mentioned horseshoe-shaped arch opening.