JPH0345334Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tracking device for a pick-up section for signal detection, which is the head section of a disk player that optically records and reproduces video signals, etc., and is particularly applicable to the guide section of a moving object. Regarding structure.

Various video disk systems have been proposed as a means of providing video information, for example, but optical video disk systems are particularly easy to duplicate and inexpensive, and are susceptible to disk wear due to non-contact readout. It is attracting particular attention because of its excellent performance and functionality, including the ability to record and play back high-quality video and audio without any noise, and the ability to perform many functions such as slow motion and random access.

By the way, in an optical disc player, for example, by using a pickup optical system as shown in FIG. 1, the laser beam emitted by the laser tube 1 is divided into the main beam and the main beam by using the first order light diffracted by the grating 2. A total of three beams are generated, and the beams are passed through a spot lens 3, fixed reflectors 4 and 5, and a Wollaston prism 6, then converted into a circularly polarized light beam by a quarter-wave plate 7, and then transferred to a disk. The signal on the disk 11 is guided to the objective lens 10 by a tracking mirror 8 that shakes the beam in the radial direction to track the above track, and a tangential mirror 9 that shakes the beam in the tangential direction to remove time axis fluctuations of the reproduced signal. Focused on the recording surface. Then, the reflected beam, which is modulated by the pits of the video disk 11 and totally reflected by the reflective film and whose rotational direction of circularly polarized light is reversed, follows the optical path in the opposite direction and passes through the quarter-wave plate 7 again.
converted into linearly polarized light perpendicular to the incident beam,
The light then passes through the Wollaston prism 6 and reaches the photodiode 13 via the cylinder lens 12, where it is detected. By the way, as shown in FIG.
Roller 14 so that it slides in a straight line up to Ao′
It is accessed by being disposed and supported on a movable part 14 that is linearly reciprocated by a, 14b, 14c, and 14d. By the way, as shown in FIG. 3, the movable part 14 reciprocates in the directions of arrows A and B along each of these rails 15 and 16 between a pair of guide rails 15 and 16 as fixed side members. When the movable part 14 is held by these rails 15 and 16 so as to be freely movable, the facing surfaces 15A and 1 of the rails 15 and 16 and the movable part 14 are
Grooves 17, 18, 19, 20 each having a V-shaped cross section are formed in 4A, 16B, and 14B so that the opening sides thereof face each other.
These opposing grooves 17, 18 and 19 are carved.
There is one in which cross rollers 21, 21 are arranged between and 20.

That is, as shown in FIG. 3B, the opposing grooves 17 and 18 and 19 and 20 are in a state in which parallelogram-shaped roller insertion gaps 22 and 23 are held, and one of the grooves 17 and 18 is A cross roller 21 is interposed between opposing groove walls 17A and 18A or 17B and 18B, and each groove 1 of the other
A cross roller 21 is interposed in rolling contact between opposing groove walls 19A and 20A or between 19B and 20B in the groove walls 9 and 20. In such a configuration, the movable portion 14 is positioned in the X direction and Y direction in FIG. 3B by the respective close rollers 21, 21, and is movable only in the direction of the arrow A-B in FIG. 3A. becomes.

However, with the above structure, the grooves 17, 18, 19, and 20 having the V-shaped cross section need to be machined with high precision, and the guide rails 15 and 16 must be fixed to the base (not shown) with high precision. must be done.

The present invention was devised in view of the above circumstances, and is easy to process and assemble. The purpose is to provide a simple feeding device.

That is, in the present invention, a roller group consisting of at least three rollers is arranged and supported on both sides of the moving direction of the movable part, and the rotating shafts of the rollers in the roller group are arranged so that the inclination angles are alternately different by 90 degrees. In addition, the integrated holder is provided with a pair of guide surfaces on which every other roller in each roller group rolls, and these guide surfaces face upward and face each other in an inclined manner forming an angle of 90 degrees. Further, the holder is provided with a stopper having a presser surface that protrudes above each of the guide surfaces at right angles to the guide surfaces, and on this presser surface, the rollers in the group of rollers are attached. The present invention is characterized in that rollers other than those that roll in contact with the guide surface are supported by rolling in contact with the guide surface.

Hereinafter, one embodiment of the present invention shown in each of the drawings of FIGS. 4 to 6 will be described.

Reference numeral 30 in these figures is a movable part, in which optical system elements (not shown) are arrayed and supported, and an optical system pickup part is integrally provided. The moving direction of this movable part 30 is in the directions of arrows A and B, and roller groups 3 are provided on both sides 30A and 30B along this moving direction.
1 and 32 are arranged and supported. That is, one roller group 31 arranged on one side 30A consists of three rollers 33, 34, 35, and the other roller group 32 arranged on the other side 30B consists of another three rollers 36, 37, It consists of 38 pieces. In the illustrated example, one of the roller groups 31, middle roller 33,
35 and the rollers 34 are provided with their axial centers projecting in directions 90 degrees different from each other, and the other roller group 3
2. The middle rollers 36, 38 and the roller 37 have their axial directions protruding in inclined directions that are 90° different from each other. That is, among the above rollers 33 to 38,
The rollers 33, 35, 36, and 38 are placed on guide surfaces 40, 41 of an integrated holder, which will be described later, and the other rollers 34, 37 are pressed from above by pressing surfaces 48C, 49C of fixtures 48, 49, which will be described later. It is a transposition. Therefore, among the above-mentioned rollers, rollers 33, 35 and rollers 36, 38 have mutually protruding inclination angles of their axes that are different from each other by 90 degrees, and similarly, the protruding inclination angles of the axes of rollers 34 and 37 are also different from each other by 90 degrees. The rollers 33, 35, 36, and 38 are oriented 90 degrees in a different direction.

Next, the integrated holder 39 that movably supports the movable part 30 will be explained. This holder 39 has a pair of left and right inclined guide surfaces 40, 41.
are arranged opposite to each other so as to be parallel to each other in the moving direction of the movable portion 30. That is, these guide surfaces 40 and 41 are formed to have different inclination angles of 90 degrees. Also, along these guide surfaces 40, 41, a fixture mounting surface 4 having fixing screw holes 46a, 46b, 46c and 47a, 47b, 47c is provided on the upper surface of the protruding portions 42, 43.
4,45 are formed.

Further, reference numerals 48 and 49 denote fixing devices, which have bent portions 48a and 49a in the middle along the longitudinal direction, and one side portion of the bent portions 48a and 49a has a flat plate shape and has a screw insertion hole 50a. , 50b, 50c and 51
a, 51b, 51c formed thereon, an overlapping mounting portion 48b on the fixture mounting surfaces 44, 45;
49b, and the bent portions 48a, 49a.
The other side is attached to the mounting parts 48b and 49b.
It is formed with an upward slope in the 45° direction, and roller pressing surfaces 48c and 49c are formed on the lower surface thereof. Note that the holding surfaces 48c and 49c protrude in a direction 90° different from the corresponding guide surfaces 40 and 41,
These pressing surfaces and guide surfaces 48c, 40 and 49c
and 41 form a V-groove shape that opens at right angles to each other. Therefore, in order to movably assemble the movable part 30 to the holder 39, before attaching the fixtures 48 and 49, the corresponding rollers 33 and 35 and 36 and 38 are placed in contact with each other on the guide surfaces 40 and 41. do. In this state, the rollers 34 and 37 remain idle. Therefore, the mounting portions 48b and 49b of the fixtures 48 and 49 are stacked on the corresponding fixture mounting surfaces 44 and 45, and the mounting screws 52
a, 52b, 52c and 53a, 53b, 53c
Fixing screw holes 46 from corresponding screw insertion holes 50a, 50b, 50c and 51a, 51b, 51c
a, 46b, 46c and 47a, 47b, 47c
Tighten the screws and secure. Then, each fixture 4
Roller pressing surfaces 48c and 49c of rollers 8 and 49 are rolled into contact with each other so as to press the rollers 34 or 37 from above, thereby restricting the upward protrusion of the movable portion 30.

In this way, the movable part 30
The optical system pickup (not shown) mounted on the movable section 30 can be linearly tracked in the radial direction of the video disk.

As described above, in the present invention, each roller group 31, 32 of the movable part is brought into contact with the opposing guide surfaces 40, 41 of the integral holder 39, and is pressed by the fixing devices 48, 49, so that the movable part It can be easily and accurately attached to a predetermined dimensional position without adjusting the position of 30. Moreover, the integrated holder 39 can be constructed as a simple structure that can be formed by a simple processing method such as die casting, plastic molding, etc. without relying on complicated machining, and can improve accuracy and reduce costs. be.

[Brief explanation of the drawing]

Fig. 1 is a perspective view schematically showing the configuration of an optical system pickup in a video disc player, Fig. 2 is a schematic plan view for explaining the principle of linear tracking, and Fig. 3 is a conventional optical pickup. The outline of the moving device for the thread (movable part) is shown, with A being a perspective view and B being an enlarged partially cutaway front view. FIG. 4 is an exploded perspective view showing an embodiment of the present invention, FIG. 5 is a plan view, and FIG. 6 is the same as shown in FIG.
-6 It is a vertical front view. 30...Movable part, 31, 32...Roller group, 3
3-38...Roller, 39...Integrated holder, 4
0, 41... Guide surface, 44, 45... Fixture mounting surface, 48, 49... Fixture, 48c, 49c...
...presser surface.

Claims (1)

[Scope of utility model registration request] Roller groups consisting of at least three rollers are arranged and supported on both sides of the moving direction of the movable part, and the rotating shafts of the rollers in the roller group are arranged alternately so that the angle of inclination differs by 90 degrees, and The body holder is provided with a pair of guide surfaces on which every other roller in each of the roller groups rolls, and the guide surfaces are arranged facing upward and facing each other in an inclined manner forming an angle of 90 degrees, and further The holder is provided with a stopper having a presser surface that protrudes above each of the guide surfaces at right angles to the guide surfaces. A guide device for a movable body in an optical display or the like, characterized in that rollers other than those in contact are supported by rotating them.