RU2357117C1 - Driving cable for reciprocal motion of mechanisms - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention is related to machine building, to drives for reciprocal motion of units and parts. Driving cable for reciprocal motion of mechanisms comprises movable metal core with protective coat in the form of synthetic bush with ribbed surface. Cable is installed inside concentric armored shell with walls made of synthetic material in the form of internal and external bushes. On surface of shell internal bush along its whole length there is at least one rib arranged with helical shape with preset pitch of turns. Helical rib has conical shape in cross section and is arranged with spiral pitch that provides for shell contact with core only along surface of helical rib at any permissible bending of cable.

EFFECT: reduced friction forces during core displacement relative to shell and according reduction of forces applied by operator to control lever.

3 cl, 1 dwg

Description

The invention relates to mechanical engineering, to drives reciprocating movement of nodes and parts. One of the main links for transmitting movement in these drives is the inventive cable.

Known synthetic cable [1], containing a core of high strength elements and a sheath of interwoven low-modulus complex filaments with a coating. The core elements are made on the basis of polyamide fibers. The shell is made of complex polycaproamide yarns, and the coating consists of a composition based on a copolymer of tetrafluoroethylene with vinyldenofluoride and carbon black.

The cable has a high resistance to thermal effects and operational reliability. The cable design provides reliable transmission of significant pulling forces, however, the cable cannot be used for reciprocating movements, because not designed to transmit pushing forces.

Also known is a drive cable for reciprocating movement of mechanisms [2]. The cable contains a movable metal core with a protective coating in the form of a synthetic sleeve with a ribbed surface. It is installed inside a concentric armored shell with walls made of synthetic material in the form of inner and outer bushings.

The ribbed surface of the sleeve protecting the core provides a reduction in the area of contact with the surface of the inner sleeve of the shell, as a result of which the friction forces arising from the reciprocating movements of the core relative to the shell and, accordingly, the forces exerted by the operator on the control lever are reduced. Touching occurs along solid lines formed by the tops of the ribs along the entire length of the cable. To achieve an even greater reduction in friction forces, it is necessary to reduce the contact area of the core with the shell.

The task of the invention is to create a drive cable design, the core of which has a smaller contact area with the sheath.

The technical result consists in reducing the friction forces when the core moves relative to the shell and the corresponding reduction in the forces exerted by the operator to the control lever.

The technical result is achieved by a drive cable for reciprocating movement of mechanisms, containing a movable metal core with a protective coating in the form of a synthetic sleeve with a ribbed surface. The cable is installed inside a concentric armored shell with walls made of synthetic material in the form of inner and outer bushings. The new lies in the fact that on the surface of the inner sleeve of the shell along the entire length is made at least one rib of a spiral shape with a given pitch of turns. The spiral rib has a conical cross-sectional shape and is made with a spiral pitch providing contact of the shell with the core only along the surface of the spiral rib for any permissible bending of the cable.

The drawing in axonometric projection presents the inventive drive cable. The drawing contains a cross-section and a longitudinal section of a cable.

The cross section shows a core with a metal tow 1 and a protective coating in the form of a synthetic sleeve 2 with ribs 3 symmetrically located on its outer circumference. On the inner surface of the sleeve 4 is made of a spiral rib 7 with a cross section of a conical shape. Touching the core with the shell occurs at points, i.e. touch area is minimized. The drawing shows the contact points of the ribs of the protective sleeve of the core with the spiral rib 7 of the inner sleeve of the shell: L and M. For each coil of the spiral there are 10 points of contact (according to the number of edges on the protective sleeve of the core).

The proposed cable design can significantly reduce the efforts exerted by the operator to the cable drive, due to the minimum contact area of the rubbing surfaces.

Information sources

1. RF patent No. 2071517.

2. Application WO 2007073501, IPC F16C 1/00, 1/10, 1/20, 1/26 - prototype.

Claims (3)

1. A drive cable for reciprocating movement of mechanisms, comprising a movable metal core with a protective coating in the form of a synthetic sleeve with a ribbed surface, mounted inside a concentric armored shell with walls made of synthetic material in the form of internal and external bushings, characterized in that on the surface at least one spiral rib with a predetermined pitch of turns is made along the entire length of the inner sleeve of the shell. 2. The drive cable according to claim 1, characterized in that the spiral rib has a conical shape in cross section. 3. The drive cable according to claim 1, characterized in that the spiral rib is made with a spiral pitch providing contact of the shell with the core only along the surface of the spiral rib for any permissible bending of the cable.