JPH01267622A - Actuator for camera - Google Patents

Abstract

PURPOSE:To facilitate the manufacture of the actuator by providing a bobbin with projection part to be pressed against body parts and a yoke respectively and dividing the bobbin into two upper and lower parts, providing recess and projection parts for positioning on the division surfaces and also providing bearing parts for a rotor to the nearly center parts of rotor chambers, and further forming a projection fitting part integrally. CONSTITUTION:The bobbin is provided on an object position with the projections 23a and 23b, and 33a and 33b to be pressed against the body parts 22 and 32 wound with coils 6 and 7 longitudinally and the yoke 1, and divided by two into the upper bobbin 3 and lower bobbin 2. Then recess parts 25 and 26 and projection parts 35 and 36 for positioning at the time of the assembly on the division surfaces are provided, the bearing part 29 and 39 for the rotor 4 are provided on the nearly center pats of the rotor chambers 21 and 31, and the fitting part 34 which projects from the upper edge of the yoke 1 is formed integrally with the projection part 33a. Here, when the upper and lower bobbins 3 and 2 are assembled, the rotor 4 is stored inside, both ends of a shaft 5 are borne by the bearing parts 29 and 39, and the projection parts 35 and 36 are fitted in the recess parts 25 and 26 for positioning to put the lower bobbin 2 and upper bobbin 3 together. Consequently, their axes never shift from each other and an operator can easily assemble them without skillfulness.

Description

[Detailed description of the invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera actuator used as a drive source for an automatic aperture mechanism installed in various cameras such as photographic cameras, television cameras, and video cameras. [Prior Art] As this type of camera actuator, there are those with a configuration disclosed in Japanese Patent Application Laid-Open No. 62-81962 and one with a configuration disclosed in Japanese Patent Publication No. 82-19097, filed by the same applicant. Both are well known.

[Problem to be solved by the invention]

The former prior art has a structure in which seven flange portions for fixing the actuator inside the camera are integrally formed and project from the upper edge of the housing or yoke. Since this yoke is generally formed by drawing, the protruding seven flange portions as described above make it difficult to manufacture, and the presence of the flange portions makes the magnetic force distribution uneven. Adsorption phenomena and torque unevenness occur, resulting in product variations and problems such as L. Furthermore, in the latter conventional example, there is no attachment means on the yoke or coil frame, and a separate attachment member is required when incorporating it into the camera, resulting in a large number of parts. Not only that, but the coil frame is composed of vertically divided left and right frames, and when assembling these left and right frames, it is necessary to store the permanent magnet inside. The problem is that the combination of the parts when they are combined is not constant, and the eccentricity of the rotating shaft occurs due to the combination error, which also causes errors in the mounting position of the yoke, resulting in a product with variations.

[Means for Solving the Problems] As a specific means for solving the problems of the conventional example, the present invention includes a cylindrical yoke, a bobbin that houses a rotor in an internal rotor chamber, and has a coil wound on the outside. The bobbin is provided with protrusions for pressure contact between the body part on which the coil is wound in the vertical direction and the yoke at the desired position, and is divided into two parts, an upper bobbin and a lower bobbin, and the bobbin is assembled on the divided surface. A concavo-convex portion is provided for positioning during alignment, a rotor bearing portion is provided approximately in the center of the rotor chamber, a window hole communicating with the rotor chamber is provided in one side of the protruding portion, and The present invention provides an actuator for a camera, characterized in that a ventilation path is provided along the outer edge of the window hole, and a mounting portion protruding from the upper edge of the yoke is integrally formed on the other side of the protruding portion, and the yoke itself Since there is no mounting part on the bobbin, it is easy to manufacture. Furthermore, by dividing the bobbin into two parts, the eccentricity of the rotor does not occur, and the assembly work is easy. Furthermore, the ventilation passage allows for internal heat dissipation. The effect will be greater. [Embodiment] Next, the present invention will be described in more detail based on the illustrated embodiment. Reference numeral 1 is a cylindrical yoke, and a bobbin that is press-fitted into the yoke is a lower part divided into upper and lower parts. It is composed of a bobbin 2 and an upper bobbin 3, and these upper and lower bobbins are molded from plastic. The lower bobbin 2 is provided with a rotor chamber 21 in which a rotor or permanent magnet 4 is housed approximately in the center thereof, and a body portion 22 for winding a coil around the circumferential surface of the rotor chamber is provided at a target position.
Projections 23a and 23b having a substantially crescent-shaped cross section that come into pressure contact with the inner wall surface of the yoke 1 are integrally formed at symmetrical positions. A plurality of terminals 24 to which coil ends and external power supply lines are attached are attached to the lower surfaces of these protrusions in a planted state, and each of these terminals is provided with a slit portion 24a at its tip. Furthermore, one protrusion 23
The upper surface of a is provided with four parts 25 for positioning when combined with the upper bobbin 3, and the other protruding part 23b is also provided with a recess 26 for positioning, and the side surface is provided with a recess 26 for positioning in the rotor chamber 21. A communicating window hole 27 is provided, and a ventilation passage 28 is formed along the outer edge of the window hole 27. Further, a bearing portion 29 on which the rotating shaft 5 of the rotor 4 is supported is provided approximately at the center of the bottom of the rotor chamber 21. Similar to the lower bobbin 2, the upper bobbin 3 is provided with a rotor chamber 31 in which the rotor 4 is housed approximately in the center thereof,
The coils are wound around the circumferential surface of the rotor chamber by providing the body portion 32 at a target position and integrally forming a protrusion 33a133b having a substantially crescent-shaped cross section in pressure contact with the inner wall surface of the yoke 1 at the target position. . An angular attachment part 34 is integrally formed on the upper part of the protruding part 33a, and a protruding part 35 that fits into the recess 25 for positioning the lower bobbin 2 is formed protruding on the lower surface. It is. Furthermore, protrusions 36 that fit into the alignment recesses 26 are formed protrudingly on the lower surface of the other protrusion 33b, and a window hole 37 that communicates with the rotor chamber 31 is provided on the side surface. A ventilation path 38 is formed along the outer edge of the hole 37, and a bearing portion 39 is further formed approximately in the center of the rotor chamber 31. When combining the upper and lower bobbins formed in this way, the rotor 4 is housed inside, both ends of the rotor shaft 5 are respectively supported by the bearing portions 29 and 39 of each bobbin, and the convex portion 35
．． By fitting the lower bobbin 2 and the upper bobbin 3 together by fitting the lower bobbin 2 and the upper bobbin 3 into the recesses 25 and 26 for positioning, the axes can be easily assembled without shifting the axes and without requiring skill on the part of the operator. can. After both bobbins 2.3 are combined, a predetermined amount of coil 6.7 is wound around the body 22.32. At this time, the end of each coil is held by being held by the slit part 24a of the terminal 24, and when the coil has been wound, the end part is further held by being held by the slit part 24a of another terminal. Winding work can be done easily. Also, since there is sufficient space for winding the coils 6 and 7, a sufficient number of turns can be obtained, thereby making it possible to generate high torque. After the coils 6 and 7 are wound around the bobbin, the external power supply lines 8 are connected to the terminals 24 by soldering or other means, and then each terminal 24 is bent inward and the bobbin is inserted into the yoke 1. Press-fit and install. If the yoke 1 used in this case is a cylindrical body with a bottom, a predetermined hole 1a may be provided at the bottom of the cylindrical body to allow the external power supply line 8 to be taken out. In this way, when the bobbin is press-fitted and stored in the yoke 1, the ventilation passage 28.38 opens upward with a predetermined gap between it and the yoke 1, and the rotor chamber 21.31 is substantially opened to the outside. In this state, the heat dissipation effect becomes greater. Furthermore, the mounting portion 34 provided on the upper bobbin 3 is attached to the yoke 1.
It is located protruding from the upper edge of the camera, and can be easily installed inside a camera or the like via the mounting portion. [Effects of the Invention] As explained above, the camera actuator according to the present invention includes a cylindrical yoke and a bobbin that houses a rotor in an internal rotor chamber and has a coil wound around the outside. A protrusion is provided for pressure contact between the chest and the yoke, where the coil is wound in the longitudinal direction at the target position, and the bobbin is divided into two parts, an upper bobbin and a lower bobbin, and the bobbin is used for positioning on the divided surface when assembling the bobbin. A rotor bearing portion is provided at approximately the center of the rotor chamber, a window hole communicating with the rotor chamber is provided on one side of the protrusion, and a window hole is provided along the outer edge of the window hole. By providing a ventilation passage and further integrally forming a mounting part protruding from the upper edge of the yoke on the other of the protruding parts, the protruding part of the upper bobbin can be attached to the protruding part of the upper bobbin without providing a mounting part on the yoke. The provision of the mounting portion provides an excellent effect in that it is easy to manufacture, and the magnetic properties are uniform and there is no variation in the product. Also, by dividing the bobbin into two parts (upper and lower), the combination of
This has the advantage that not only almost no errors occur during the process, eccentricity of the rotor does not occur, but also the assembly work is easy. Furthermore, by providing a window hole that communicates with the rotor chamber and providing a ventilation path along the outer edge of the window hole, the temperature increase in the rotor chamber due to the heat generated by the coils can be dissipated from the inside in a fali-like manner. It also has the excellent effect of preventing performance deterioration due to overheating. 4.L of the drawing! DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a perspective view of the main parts of a camera actuator according to the present invention shown separately, FIG. 2 is a longitudinal sectional view of the actuator, and FIG. 3 is a plan view of the actuator. 1... Yoke 2... Lower bobbin 3... Upper bobbin 4... Rotor 5... Rotor shaft 6.7... ... Coil 8 ... External power supply line 21.31 ... Rotor chamber 22.32 ...
...Body portions 23a, 23b, 33a, 33b -----
--Protrusion 24...Terminal 25.26
・・・・・・Recess 27.31 ・・・Window hole 2
8.38...Vent passage 29.39...Bearing section 34...Mounting section Patent applicant: Fujita Electric Co., Ltd., Figure 1, Figure 2

Claims (2)

[Claims] (1) Consisting of a cylindrical yoke and a bobbin that stores a rotor in an internal rotor chamber and has a coil wound around the outside, the bobbin is connected to a body and a yoke in which the coil is wound vertically at a target position. The bobbin is divided into two parts, an upper bobbin and a lower bobbin, and a concave and convex part is provided on the divided surface for positioning when assembling the bobbin. A rotor bearing portion is provided, a window hole communicating with the rotor chamber is provided on one side of the protrusion, a ventilation path is provided along the outer edge of the window hole, and a yoke is provided on the other side of the protrusion. A camera actuator characterized by integrally forming a mounting portion protruding from an upper edge. (2) The camera actuator according to claim (1), further comprising a plurality of terminals to which ends of the coil are fixed to the lower surface of the lower bobbin.