DESCRIPTION

The invention is about a ring device (8) for the attachment of function - control accessories (5) to camera (2) lenses (1) for the purpose of controlling the functions of a lens (1 ).

Functions of a lens (1) are defined as the aperture opening (iris), the focusing distance (focus) and the focal length (zoom). For the control of these functions, lenses (1) have built-in peripheral components bearing a toothed surface in the form of gears (4). To control the movement of the gears (4), already known function-control accessories (5) are affixed alongside the lens by clamping onto cylindrical rods (7) attached to an additional accessory in the form of a base or a cage (3) attached to the body of the camera (2). These already known function-control accessories (5) affect mechanically the gears (4) thereby rotating them, at the operator’s command, thus controlling the functions of the lens (1).

All currently known and used systems for mounting lens (1) functioncontrol accessories (5) (Drawing 2) are attached to the body of the camera (2) or its base (3). Attached to the body of the camera (2) or its base (3), function-control accessories (5) controlling the functions of the camera lens (1) have been proven to cause lens shift due to torque with the vulnerable point being the lens attachment point to the camera (6).

According to the currently applied method of the already known systems for mounting function-control accessories (5), the exercise of external force at any point of the lens (1) results in a multiple force being exercised at the lens attachment point to the camera (6) and the vulnerable lens attachment point to the camera (6) is being exposed to a force beyond that it can withstand based on its design and the endurance of the materials being used. As an immediate result of this, either the lens (1) is displaced during capture of footage causing undesired aesthetic results or even the lens attachment point to the camera (6) is permanently damaged and plastically deformed causing damage both ways. Additionally, regarding appliances on longer lenses (1) (i.e. telephoto and zoom lenses), longer rods (7) are needed, which result in lesser control precision of the function-control accessories (5) as elastic deformation of the rods (7) reportedly takes place when their length and distance from the support point of the base (3) of the camera (2) increases.

Main advantage of this invention is the relocation of the point of reference and attachment for the mounting of function-control accessories (5) from the camera (2) or its base (3) to the lens (1) itself and the following elimination of all of the above-mentioned disadvantages of lens (1) displacement during capture of footage and lens attachment point to the camera (6) being plastically deformed, by forming a closed mounting system independent of the camera (2). An advantage of the present invention is also the volume and weight reduction of the whole camera (2) equipment via the use of shorter rods (7) and the elimination of the use of the above-mentioned base (3) or cage mounted on the camera. Additional advantage of the present invention is the elimination of the need of long rods (7) via the opportunity to use shorter rods (7) which undergo minimal elastic deformation compared to that observed in the case of longer rods (7), resulting in increased precision and control by the lens function-control accessories (5) on the lens (1).

The present invention consists of a ring device (8), in a shape of a closed circle, which is applied around the circumference of a stationary nonmoving segment of the camera (2) lens (1) barrel and has one or more attachment points (9, 10) of function-control accessories (5) for the purpose of controlling the functions of a camera (2) lens (1 ).

The ring device (8), according to the invention, may be made from a solid material such as metal, polymer or composite material that may exhibit minimal elasticity for the purpose of applying to various lens (1) barrel diameters by means of inserts (14).

The points of attachment (9, 10) of function-control accessories (5) of the ring device (8), according to the invention, may consist of one or more female threads (10), positioned perpendicular to the form of the mounting system to the lens (1) or/and one or more clamping mechanisms (9) of various diameter (for example 12mm, 15mm or 19mm) for the attachment of rods (7) of standardized diameter positioned parallel to the form of the lens mounting system with the use of clamps (11).

The ring device (8) is attached to the barrel of the camera (2) lens (1) by means of an in-built hinged segment (12) allowing it to open and close around the circumference of a stationary non-moving segment of the camera (2) lens (1) barrel. Diametrically opposite to the hinge segment (12), i.e. at an angle of about 180 degrees from the centre of the ring device (8) is an in-built clamping mechanism (13) for the purpose of mounting the ring device (8) on the lens (1) by using a clamp (11) similar to the clamping mechanisms (9) for the attachment of rods (7).

The inserts (14) may consist of a flexible plastic or composite material, in the shape of an open-ended circle of a diameter slightly smaller than that of the ring device (8), which aforementioned circle is open to an extent corresponding approximately to the surface of the perimeter occupied by the clamping mechanism (13) for the mounting of the ring device (8) on the lens (1).

The characteristic features of the invention are defined in the claims.

An example of the application of the invention is presented as follows by referencing Drawings 3, 4, 5, 6 and 7.

Drawing 1 illustrates a cinema/photographic camera (2) with its lens (1). Drawing 2 illustrates a cinema/photographic camera (2) on a base (3), exhibiting the currently used method of mounting function-control accessories (5) on the base (3) of the camera (2), according to the existent state of the art.

Drawings 3 and 4 illustrate, as a suggested example of application of the invention, a cinema/photographic camera (2) with an attached ring device (8) to a stationary non-moving segment of the barrel of the lens (1), according to the invention. To the shown point of attachment (9) of functioncontrol accessories (5) of the ring device (8) a cylindrical rod (7) has been applied, on which the already known lens (1) function-control accessories (5) have been attached. This is preceded by the opening of the ring device (8) using the hinged segment (12), as it is illustrated in Drawing 5 and 6 and its attachment to the barrel of the lens (1), using the clamping mechanism (13) located diametrically opposite of the hinged segment (12) as illustrated in Drawings 5 and 6.

Drawing 5 illustrates the ring device (8), according to the invention, with attachment points (9, 10) for function-control accessories (5): two clamping mechanisms (9) for the attachment of rods (7) of standardised diameter with the use of clamps (11), of which the attachment points to the body of the ring device form an 120° angle from the centre of it and a female thread (10) positioned perpendicular to the form of the mounting system to the lens (1). It also illustrates the hinged segment (12) of the ring device (8) which allows its opening for it to be attached around the circumference of a stationary non-moving segment of the barrel of the camera (2) lens (1), as well as the clamping mechanism (13), positioned diametrically opposite at an angle of 180° degrees from the centre of the ring device (8) by using a clamp (11) similar to the clamping mechanisms (9) for the attachment of rods (7).

Drawing 6 illustrates the ring device (8) opened by means of the hinge segment (12), with the one half of its perimeter extended, in order to be then attached around the circumference of the barrel of the camera (2) lens (1).

Drawing 7 depicts inserts (14) of various dimensions, according to the invention, as well as the method of mounting on the inner side of the ring device (8).