GB2106586A

GB2106586A - Bearing bush assembly for the bridge of binoculars

Info

Publication number: GB2106586A
Application number: GB08224656A
Authority: GB
Inventors: Horst Mottig
Original assignee: VEB Carl Zeiss Jena GmbH
Current assignee: Jenoptik AG
Priority date: 1981-09-01
Filing date: 1982-08-27
Publication date: 1983-04-13
Also published as: GB2106586B; FR2512219A1; DD206244A1; FR2512219B1; DE3220764A1

Abstract

A bearing bush assembly for the bridge of a pair of binoculars has a diaphragm (13) fixed annularly around the bush (4) and axially clamped between a screw-threaded ring (15) on the bush and one (2') of the hinged arms (2,2') of the bridge which embrace the bush (4), thereby permitting continuous adjustment and readjustment of the bending moment of the bridge. Two such bearing bush assemblies pivotally interconnect the two telescope units (1,1') of the binoculars with a drive knob (18) disposed therebetween. <IMAGE>

Description

SPECIFICATION Bearing bush assembly for the bridge of binoculars The invention relates to binoculars and in particulay to the bridge assembly which pivotally interconnects the two telescope units forming such binoculars.

Bridges having central drive focussing for binoculars are already known. The hinges of these bridges are constructed such that bearing bushes are disposed in recesses in hinged arms and have a collar attachment on one end and a screw-thread on the opposite end. The required bending moment of the bridge i.e. the force required to bend the bridge and thereby adjust the spacing between the telescope devices is obtained by pressing elements screwed onto or into the screwthread of the bearing bushes.

After the required moment has been set, the screwed-on or screwed-in pressing elements and the bearing bushes, together with one arm of the hinge, are secured against angular displacement, usually by pinning these elements. Disadvantage of these solutions are that continuous adjustment and readjustment of the bending moment of the bridge cannot be effected, and that the relatively large amount of backlash in the hinges resulting from the two cylindrical hinge fits assembled in pairs for each bearing, causes non-parallelism of the two telescope tubes. Expensive metal-cutting operations are required for fixing the bending moment of the known hinge bridges of binoculars, the fixing elements are subjected to considerable wear and, in accordance with the technical solutions already known, continuous readjustment of the bending moment is not available.

An object of the invention is to provide a bearing bush for the bridge of a pair of binoculars, which is capable of continuous adjustment and readjustment of the bending moment of the bridge.

In accordance with the present invention, there is provided a bearing bush assembly for the bridge of a pair of binoculars, comprising a bearing bush having a stop at its one end and screw-threaded ring at its other end, a pair of hinged arms disposed on the bearing bush between the stop and the screwthreaded ring, one hinged arm being adjacent to the screw-threaded ring and the other hinged arm being adjacent to the stop, and an annular diaphragm which is rigidly connected to the bearing bush between the screw-threaded ring and one of the hinged arms.

Advantageously, the annular diaphragn is provided with radial slots which subdivide the annular diaphragm into sectors.

The action of the diaphragm can be promoted by an annular reinforcement provided along the periphery of the annular diaphragm and also along the periphery of the diaphragm sub-divided into sectors.

The hinged arms of the bridge are connected to the tubular bodies of the two telescope units of the binoculars both at the eyepiece end and at the objective end, so that a respective bearing bush assembly connects a respective pair of hinged arms.

The invention will be further described, by way of example only, with reference to the accompanying drawing which shows diagrammatically a bridge for a pair of binoculars having central drive focussing and a drive knob located between the hinged arms.

Pairs of hinged arms 2, 2' and 3, 3' are secured to the tubular bodies 1 and 1' of the two telescope units which are illustrated only diagrammatically in the drawing. The hinged arms 2 and 2' embrace a first bearing bush 4, and the hinged arms 3 and 3' embrace a second bearing bush 5. The bearing bush 4 has two external diameters 6 and 11. The portion of the bush 4 having the diameter 6 is disposed within the hinged arm 2 and, in this embodiment, the bearing bush 4 and the hinged arm 2 are rigidly interconnected in that they are urged against one another at the annular end surface 8 by means of a screw-threaded member 7. The hinged arm 2' is rotatably mounted on the portion of the bush having the diameter 11.

The bearing bush 5 is screwed into the hinged arm 3 by means of screw thread 9 and is drawn against the annular shoulder surface 10. The hinged arm 3' is rotatably mounted on the portion of the bush 5 having the diameter 12.

Annular diaphragms 13 and 14 are rigidly connected to the bearing bushes 4 and 5, respectively, and their couter edge regions abut respectively against the hinged arms 2' and 3' and are movable for a distance in the direction of the bridge axis A-A.

The annular diaphragms 13 and 14 are axially clamped by screwing screw-threaded rings 15 and 16 onto the bearing bushes 4 and 5 respectively.

The bending moment required during displacement of the tubular body 1' of the binoculars relative to the tubular body 1, and the associated rotation of the hinged arms 2' and 3' about the diameters 11 and 12 of the bearing bushes 4 and 5 relative to the hinged arms 2 and 3, are produced by axial displace ment of the annular diaphragms 13 and 14 which, as a result of their axial displacement, maintain the friction at the surfaces of the annular diaphragms 13 and 14 and at the end faces 8 and 10 of the hinged arms 2' and 3' substantially constant. Independent loosening of the screw-threaded rings 15 and 16, and thus un-intentional alteration of the bending moment, is prevented by virtue of the fact that the diaphragms 13 and 14 are rigidly connected to the bearing bushes 4 and 5. Displacement of the central spindle 17 during focussing is effected by a drive knob 18 which incorporates a screw-thread 19 and which is axially fixed on the bearing bush 5 by means of a screw-thread 20. A screw 21 serves to limit the displacement.

1. A bearing bush assembly for the bridge of a pair of binoculars, comprising a bearing bush having a stop at its one end and a screw-threaded ring at its other end, a pair of hinged arms disposed on the bearing bush between the stop and the screwthreaded ring, one hinged arm being adjacent to the screw-threaded ring and the other hinged arm being adjacent to the stop, and an annular diaphragm which is rigidly connected to the bearing bush between the screw-threaded ring and one of the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Bearing bush assembly for the bridge of binoculars The invention relates to binoculars and in particulay to the bridge assembly which pivotally interconnects the two telescope units forming such binoculars. Bridges having central drive focussing for binoculars are already known. The hinges of these bridges are constructed such that bearing bushes are disposed in recesses in hinged arms and have a collar attachment on one end and a screw-thread on the opposite end. The required bending moment of the bridge i.e. the force required to bend the bridge and thereby adjust the spacing between the telescope devices is obtained by pressing elements screwed onto or into the screwthread of the bearing bushes. After the required moment has been set, the screwed-on or screwed-in pressing elements and the bearing bushes, together with one arm of the hinge, are secured against angular displacement, usually by pinning these elements. Disadvantage of these solutions are that continuous adjustment and readjustment of the bending moment of the bridge cannot be effected, and that the relatively large amount of backlash in the hinges resulting from the two cylindrical hinge fits assembled in pairs for each bearing, causes non-parallelism of the two telescope tubes. Expensive metal-cutting operations are required for fixing the bending moment of the known hinge bridges of binoculars, the fixing elements are subjected to considerable wear and, in accordance with the technical solutions already known, continuous readjustment of the bending moment is not available. An object of the invention is to provide a bearing bush for the bridge of a pair of binoculars, which is capable of continuous adjustment and readjustment of the bending moment of the bridge. In accordance with the present invention, there is provided a bearing bush assembly for the bridge of a pair of binoculars, comprising a bearing bush having a stop at its one end and screw-threaded ring at its other end, a pair of hinged arms disposed on the bearing bush between the stop and the screwthreaded ring, one hinged arm being adjacent to the screw-threaded ring and the other hinged arm being adjacent to the stop, and an annular diaphragm which is rigidly connected to the bearing bush between the screw-threaded ring and one of the hinged arms. Advantageously, the annular diaphragn is provided with radial slots which subdivide the annular diaphragm into sectors. The action of the diaphragm can be promoted by an annular reinforcement provided along the periphery of the annular diaphragm and also along the periphery of the diaphragm sub-divided into sectors. The hinged arms of the bridge are connected to the tubular bodies of the two telescope units of the binoculars both at the eyepiece end and at the objective end, so that a respective bearing bush assembly connects a respective pair of hinged arms. The invention will be further described, by way of example only, with reference to the accompanying drawing which shows diagrammatically a bridge for a pair of binoculars having central drive focussing and a drive knob located between the hinged arms. Pairs of hinged arms 2, 2' and 3, 3' are secured to the tubular bodies 1 and 1' of the two telescope units which are illustrated only diagrammatically in the drawing. The hinged arms 2 and 2' embrace a first bearing bush 4, and the hinged arms 3 and 3' embrace a second bearing bush 5. The bearing bush 4 has two external diameters 6 and 11. The portion of the bush 4 having the diameter 6 is disposed within the hinged arm 2 and, in this embodiment, the bearing bush 4 and the hinged arm 2 are rigidly interconnected in that they are urged against one another at the annular end surface 8 by means of a screw-threaded member 7. The hinged arm 2' is rotatably mounted on the portion of the bush having the diameter 11. The bearing bush 5 is screwed into the hinged arm 3 by means of screw thread 9 and is drawn against the annular shoulder surface 10. The hinged arm 3' is rotatably mounted on the portion of the bush 5 having the diameter 12. Annular diaphragms 13 and 14 are rigidly connected to the bearing bushes 4 and 5, respectively, and their couter edge regions abut respectively against the hinged arms 2' and 3' and are movable for a distance in the direction of the bridge axis A-A. The annular diaphragms 13 and 14 are axially clamped by screwing screw-threaded rings 15 and 16 onto the bearing bushes 4 and 5 respectively. The bending moment required during displacement of the tubular body 1' of the binoculars relative to the tubular body 1, and the associated rotation of the hinged arms 2' and 3' about the diameters 11 and 12 of the bearing bushes 4 and 5 relative to the hinged arms 2 and 3, are produced by axial displace ment of the annular diaphragms 13 and 14 which, as a result of their axial displacement, maintain the friction at the surfaces of the annular diaphragms 13 and 14 and at the end faces 8 and 10 of the hinged arms 2' and 3' substantially constant. Independent loosening of the screw-threaded rings 15 and 16, and thus un-intentional alteration of the bending moment, is prevented by virtue of the fact that the diaphragms 13 and 14 are rigidly connected to the bearing bushes 4 and 5.Displacement of the central spindle 17 during focussing is effected by a drive knob 18 which incorporates a screw-thread 19 and which is axially fixed on the bearing bush 5 by means of a screw-thread 20. A screw 21 serves to limit the displacement. CLAIMS

1. A bearing bush assembly for the bridge of a pair of binoculars, comprising a bearing bush having a stop at its one end and a screw-threaded ring at its other end, a pair of hinged arms disposed on the bearing bush between the stop and the screwthreaded ring, one hinged arm being adjacent to the screw-threaded ring and the other hinged arm being adjacent to the stop, and an annular diaphragm which is rigidly connected to the bearing bush between the screw-threaded ring and one of the hinged arms.

2. A bearing bush as claimed in claim 1, wherein the other one of the two hinged arms is rigidly connected to the bearing bush and is in the form of a stop.

3. A bearing bush as claimed in claim 1, wherein the annular diaphragm is provided with radial slots.

4. A bearing bush as claimed in claim 1, includ- ing an annular reinforcement along the periphery of the annular diaphragm.

5. A bearing bush assembly substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.