JPS6038585B2 - Ball circulation type screw transmission joint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a spherical circulation type screw transmission device in which a first and a second capital member are connected through a plurality of spheres, and when one rotates, the other moves in translation. .

In particular, the invention includes substantially coaxial first longitudinal sections and second tubular sections having helical tracks on their outer and inner surfaces, respectively, the helical tracks of both members forming opposing helical passageways. The present invention relates to a spherical circulation type screw transmission screw in which a plurality of spheres are arranged in contact with each other along this passage and a return passage connecting both ends of the passage.

In the case of the upper poetry style, the first member is an Okayama-shaped round bar with a spiral groove cut on its outer surface that acts as the orbit of the sphere.

In order to avoid the drawbacks and relatively high cost of this machining process, as the first part, an ordinary metal wire is helically shaped like a spring around a rigid core such as a round bar or a flexible core such as a metal cable. It is known to use a thread-shaped wire wound in such a way that adjacent windings form part of the thread-shaped track.

Recently, it has also become possible to compress the spring and bring adjacent windings into contact with each other, omitting the core material and constructing the first section only from a spiral metal wire. However, when the spiral track for a sphere is constructed from a spirally wound metal wire, the pitch is directly related to the diameter of the metal wire used, and the pitch is at least 2 to 3 times the diameter of the metal wire used. The disadvantage is that only relatively small amounts of up to

Therefore, an object of the present invention is to provide a spherical circulation type screw transmission aid of the type described above, in which the first material is relatively inexpensive and can have an arbitrary pitch.

The purpose of this is to configure the first member with a rigid or flexible core and a metal strip wound spirally around the core, and to make the cross section of the metal strip concave outward. This is achieved by the above-mentioned type of spherical circulation type screw transmission aid according to the present invention, which forms one side of the above-mentioned spiral track and is fixed to a core material.

Preferably, the other of the tracks is formed by spirally wrapping a second metal strip having an inwardly concave cross section around the inner wall of the tubular member through which the first member passes.

Other features and effects of the present invention will be described below with reference to some embodiments thereof with reference to the accompanying drawings.

The screw transmission handle 1 shown in FIG. 1 is made up of a threaded portion 2, a nut portion 3, and a plurality of spheres 4 interposed between the two and in contact with each other along a helical transfer track 5.

The outer half of this track 5 is a spiral track 6 formed in the nut part 3.
The inner half of the metal strip 8, which is made of a helical spring 7 formed by a metal strip 8 which is made of hardened metal, is disposed opposite to the rail 6, and the metal strip 8 is concave on the side facing the sphere 4. It is bent in the width direction. In the illustrated embodiment, the cross-section of the metal strip 8 is approximately V-shaped, but any concave cross-section can be used so long as the sphere 4 can fit within and be displaced along the track 5. In the illustrated embodiment, a track 6 is formed on the inner surface of the tubular section, schematically shown as a simple tube 9 of rigid material, which is connected at both ends and forms with it a transfer circuit for the sphere 4. return passage (
(not shown) is provided.

It should be noted that the nut part 3 can also have a different structure from that shown in FIG.

For example, application date 197 July 2 by the same applicant
Any of the design shapes described in Italian Patent Application Lock No. 70-A/76 on the 7th can be used for this nut part 3. The spring 7 is wound around a cylindrical core member 10 and fixed thereto over its entire length.

The core 10' can be made of a rigid or flexible round rod or, according to a modification not shown, of a plurality of flexible metal cables, or can be made of a plurality of flexible metal cables, as well as other modifications ( (not shown), it can also be made of a resin-coated metal cable. In all cases, the core material 10, regardless of its construction, must exhibit substantially no elongation under normal axial operating loads. By wrapping the metal strip 8 around the core material 10 and fixing it, the threaded portion 2 is not only extremely precise but also has an arbitrary pitch regardless of the width of the guide rail of the sphere 4.
can be manufactured relatively inexpensively. The screw transmission handle 11 shown in FIG. 2 is very similar to the joint 1, except that the rail 6 is formed by a spring 12, which is similar to the spring 7 and is fixed to the inner surface of the tube body 9 over its entire length. Ru. In the threaded joint 13 shown in FIGS. 3 and 4, a metal strip 8 is wound around the supporting arms 1 and 11 and the same core village 10 to form a spring 14. It changes in the axial direction according to a predetermined rule.

The threaded portion 2 can be coupled to the corresponding nut portion 3 by fixing the spring 12 to the inner surface of the tubular body 15 made of an elastically deformable material by vulcanization or the like. This tubular body 15 is iron-inserted into a rigid outer tube 16 so that it can be deformed inside. The outer tube 16 is for connecting the nut portion 3 to a utilization device (not shown) or a driving device such as an electric motor (not shown), and may be omitted depending on the application. Similar to the pipe body 15, the core material 1
0 can also be a rigid body or a flexible body, but generally it is required to have rigidity in all axial directions, and to be connected to a utilization device (not shown) or a drive device such as an electric motor (not shown). A section (not shown) may also be provided. This wate 13
When transmitting motion from the driving member to the driven member (not shown) using , the spring 12 and its associated tubular body 15 expand and contract accordingly, as shown in broken lines in FIG.
5 deforms in the axial direction within the rigid tube 16.

As a result, by changing the pitch of the spring 14 in the direction of the bag of the core member 10 according to a predetermined rule, even if the drive side is operated at a constant speed, a change in the relative speed between the two members according to the predetermined rule can be caused. becomes possible. For example, when the rear arm 13 is connected between the electric motor and the utilization device to give the utilization device reciprocating rotational or translational motion, the spring 1 is coupled to the spring 12 via the sphere 4 during each reciprocating motion.
It is preferable that the portion 4 has a relatively large pitch at both ends and a relatively large pitch at the center.

In this way, reciprocating motion guidance can be achieved with extremely low stress due to inertial force and impact. When the core material 10 is made of a flexible material, the tube body 15 is also exposed, so that the saddle hand 13 can be operated even when the spring 14 is arranged along a curve. Further, in the case of the hair hand 11, the same operation is possible by replacing the Okayama body tube 9 with the hairless tube 14 according to a modified example not shown. Pipe body 15
In all embodiments in which a portable material is used, the central part is formed by a through hole 18 passing obliquely through the tube body 15 and each L-shaped guide hole, as schematically shown in FIG. The sphere 4 is returned from the negative end of the orbit 5 to the pond end by a return orbit 17 consisting of two ends constituted by 19.

One end of the guide hole 19 is iron-bonded to the weave of the through hole 18, and the end is provided in the radial direction at the end of the tube body 15 and extends into the slot 20. Each guide hole 19 is fixed to each end of the spring 12, for example, in the manner shown in FIGS. 6 and 7 of the Italian patent application. According to the principle of this invention,
Various modifications can be made to the above embodiments within the scope of the invention.

[Brief explanation of drawings]

FIG. 1 is a sectional view in the direction of the saddle of a spherical circulation type screw transmission saddle constructed according to the present invention. FIG. 2 is a mirror sectional view showing a first modified example of the rear part of FIG. FIG. 3 is a sectional view in the direction of the ball showing a second modified example of the bushate of FIG. 1. FIG. 4 is a schematic partial cross-sectional view of the flea in FIG. 3 seen from above. 1, 11, 13...
・Yabute, 2...First member, 3...Second village, 4...Sphere, 5...Spiral pilgrimage, 6 , 7...Spiral track, 8...
Metal strip, 9, 15... Tubular part village, 10...
...Inner D section, 16...sheath tube, 17...return passage. ★, Figure 2, Figure 4, Figure 3

Claims (1)

Claims: 1 comprising a first substantially coaxial elongate member and a second substantially coaxial tubular member each having a helical track on an outer surface and an inner surface;
The spiral rails of both members face each other to form a spiral path, and a plurality of spheres are arranged in contact with each other along this path and a return path connecting both ends of the path. , the first member includes an inner core and a first metal strip spirally wound around the inner core, the metal strip being fixed to the inner core and concave toward the outside. A spherical circulation screw transmission joint having a cross section forming one of the spiral tracks. 2. The joint according to claim 1, wherein the inner core portion is a rigid body. 3. The joint according to claim 1, wherein the inner core portion is a flexible body. 4 The other of the spiral tracks is constituted by a second metal strip spirally wound around the inner surface of the tubular support member through which the first member passes, and the second metal strip is wound outwardly. The joint according to claim 1, 2 or 3, wherein the joint has a concave cross section and is fixed to the tubular member. 5. The joint according to claim 1, 2, 3, or 4, wherein the tubular member is made of a flexible material. 6. Claims 1, 2, 3, 4 or 6, wherein the return path obliquely passes through the tubular member and has a flexible portion therewith. The joint described in Section 5. 7. The joint according to claim 5 or 6, wherein the tubular member made of a flexible material is inserted into the rigid sheath tube so as to be deformable in the axial direction. 8. Claim 5, wherein the first metal strip is wound in a helical manner around the inner core, and the pitch of the spiral varies according to a predetermined rule along the inner core.
The joint described in paragraph 6 or 7.