JPS6131380Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a floating head device that utilizes the force generated by the flow of fluid along the surface of a rotating disk.

Generally, as a safety mechanism for floating head devices, after the magnetic disk reaches a predetermined rotational speed, an external force such as electromagnetic force is used to bring the floating surface of the head close to the surface of the rotating disk, and an external force such as a spring is used to move the head. However, in recent years, a method has been used to rotate and stop the disc by utilizing the suction force generated by the expansion gap that widens in the direction of flow due to air flow along the surface of the rotating disc. A self-secure floating head device that is self-adsorbing and detachable has been announced. A self-adsorption/removal type floating head device does not require an external additional mechanism and can realize a self-safety function, but the center of action of the suction force due to the airflow generated in such a widening gap is biased toward the air inflow end. As a result, each floating surface was not pressurized uniformly, resulting in variations in the floating distance of each floating surface.

A conventional self-adsorption/separation type floating head device having a plurality of floating surfaces will be explained with reference to FIGS. 1 to 3. Figure 1 shows its perspective view, Figure 2,
FIG. 3 is a side view showing the principle of operation. 1st
In the figure, a plurality of head elements 1a, 1b, 1c
The floating surfaces 2a, 2b, 2c are the suction surface 4 of the suction plate 3.
The amount of protrusion from the rotary disk is regulated to be H ₁ and H ₂ (H ₁ <H ₂ ) on the air inflow side and air outflow side, respectively, along the rotating disk surface. Furthermore, the movable part 5 having these head elements 1a, 1b, 1c and the suction plate 3 is connected to a spring 6. The suction plate 3 also serves as a fixing plate for fixing the head elements 1a, 1b, 1c, and also serves as a fixing plate for fixing the head elements 1a, 1b, 1c.
The floating surfaces 2a, 2b, and 2c of b and 1c are assembled so that they are on the same plane.

Next, a state before operation in which the magnetic disk 7 is stopped is shown in FIG. 2 and will be described. In Figure 2, floating surface 2
They are fixed to a head fixing block (not shown) via a spring 6 so that the distance between a, 2b, 2c and the surface of the magnetic disk 7 is at an initial position _h0 . In this state, the gaps between the surface of the magnetic disk 7 and the adsorption surface 4 on the inflow side and outflow side of the air flow along the surface of the rotating disk are h ₀ +H ₁ and h ₀ +H ₂ (H ₁ <H ₂ ) Forms a gap that widens at the end. As the magnetic disc 7 is activated and the speed of the airflow along the disc surface increases, the airflow flowing through the widening gap acts on the suction surface 4, causing the movable part 5 to move in the direction of the rotating magnetic disc 7. is attracted to. Magnetic disk 7 shown in FIG.
In a steady state where the moving speed of head element 1 is U,
levitation force f 1 a, f 1 b, f 1 c generated on floating surfaces _2a , 2b, 2c of a, _1b , _1c , suction force generated on suction surface 4
It floats stably by maintaining floating distances h ₁ a, h ₁ b, and h ₁ c such that f ₂ and the force F ₁ from the spring 6 are balanced. The levitation forces f ₁ a, f ₁ b, f ₁ c and the spring force F ₁ proportional to the strain of the spring 6 act in the direction of moving the movable part 5 away from the surface of the rotating magnetic disk 7, and the suction force f ₂ acts in the direction of bringing it closer. It acts on

However, as shown in FIG. 3, since the point of action of the suction force _f2 is biased towards the inflow end of the suction surface 4, a counterclockwise rotational moment acts on the movable part 5.
Stable operating conditions are reached at a floating distance such that their rotational moment disappears. As a result, the floating distances h _{1 a} and h ₁ b of the outflow end head elements 1a and 1b become larger than the floating distance h ₁ c of the inflow end head elements, resulting in a wide variation in the floating distances. As a result, variations in head characteristics between channels have occurred.

This invention solves these problems by configuring a movable part with multiple suction surfaces and multiple floating surfaces that generate suction force by the flow of fluid along the rotating disk surface. To provide a floating head device in which the floating distance between a disk and a floating head is made uniform.

Examples of this invention will be described below with reference to FIGS. 4 to 6. In FIG. 4, the same reference numerals as in FIG. 1 indicate the same or corresponding parts. A suction plate 8 which also serves as a head fixing plate has suction surfaces 10a and 10b divided into two by a groove 9 substantially perpendicular to the moving direction of the magnetic disc. In addition, when the head elements 1a, 1b, 1c are fixed, the suction surfaces 10a, 10b are used as the floating surfaces 10a, 10b.
a, 2b, 2c on the air inflow and outflow sides along the rotating disk surfaces. The protrusion amounts of these floating surfaces are H ₃ , H ₄ (H ₃ < H ₄ ), H ₅ , H ₆ (H 5 < H ₄ ), respectively.
H ₆ ). Here H ₃ and
H ₅ , H ₄ and H ₆ may be equal. The movable part 11 having the head elements 1a, 1b, 1c and the suction plate 8 described above is connected to the lever 6.

Next, a state before operation in which the magnetic disk 7 is stopped is shown in FIG. 5 and will be described. Floating surfaces 2a, 2b, 2c
The movable part 11 is fixed to a head fixing block (not shown) via a spring 6 so that the distance between the head and the surface of the magnetic disk 7 is an initial position _h0 .

As the magnetic disk 7 is activated and the moving speed of the disk surface increases, the rotating disk surface and the attraction surfaces 11a, 1
The movable portion 11 is attracted in the direction of the rotating disk due to the attractive forces f ₃ a and f ₃ b generated between the widening expansion gaps formed by the rotating magnetic disks 1b, and the moving speed of the rotating magnetic disk 7 reaches U, resulting in a stable operating state. In the stable operating state shown in FIG. 6, levitation forces f ₁ a, f ₁ b, f ₁ c act in the direction of moving the movable part 11 away from the disk surface, a force F 1 proportional to the strain of the spring 6, and a force F ₁ in the direction of moving the movable part 11 closer to it. Adsorption surface 10 that acts on
Attraction forces acting on a and 10b f ₃ a, f ₃ b, floating distances h ₂ a, h ₂ b, h ₂ c such that these forces are balanced
A stable floating state is reached at .

The force F ₁ proportional to the strain of the spring 6 can be made sufficiently small by selecting the material and thickness of the spring, so that f _1a + f _1b and f _3a and f _1c and f _3b are balanced. Furthermore, as a result of the attraction force being dispersed, the points of action of the attraction force and the buoyancy force become close to each other, and as a result, the rotational moment applied to the movable portion 11 is significantly reduced. As a result, each floating surface 2
It is possible to obtain a multi-channel floating head device in which variations in the floating distances of a, 2b, and 2c are reduced and the characteristics are uniform. Moreover, when the rotation of the disk stops in the state shown in Fig. 6, the fluid forces f _1a , f _1b , f _1c , f _3a , f _3b
disappears, only the pulling force _F1 proportional to the strain of the spring 6 remains, and the movable part 11 returns to the state before operation shown in FIG. That is, the head according to the embodiment of the present invention has a self-safety function that performs adsorption and detachment operations when the disc stops rotating, and the rotating disc surface and the floating surface do not slide, so it is reliable. A high-performance floating head device can be provided.

In the above description, the case of a multi-channel head consisting of three head elements per movable part has been described, but some of these may be dummy chips having no write or read functions.
Of course, it is easily understood that the movable part may have a floating surface consisting of three or more head elements.

Furthermore, in the above embodiments, the spring supporting the movable part is a cantilever spring, but the effects of the present invention can be obtained regardless of the form of the gimbal spring or other spring.
Of course, it will be demonstrated. In addition, in a floating head that requires a relatively large floating distance of about 1 to 2 μm, an inclined surface that increases the levitation force is installed on the air inflow end side of the floating surface along the rotating disk surface. can be provided. It will be easily understood that the effects of the present invention can be exerted even in this case.

Further, in the description of the embodiments of this invention, a magnetic disk was described as the rotating disk, but other disks such as video disks can be used, and the fluid is not limited to air.

In this way, in this invention, the surface of the head supporting movable member facing the recording or reading rotating disk has a downward slope from the inflow side to the outflow side of the fluid when the rotating disk rotates. A plurality of suction surfaces are formed along the direction of fluid flow, which are inclined to generate a suction force in the direction of the disc due to the flow of fluid, and on each suction surface, a suction force opposite to the suction force is formed due to the flow of fluid. Since the head is provided with a floating surface that generates a floating force in the direction, the floating distance between the rotating disk and the floating head can be made uniform.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a conventional self-adsorption/separation type floating head device having a plurality of floating surfaces and suction plates, and Figs. 2 and 3 show the operating principle of the device shown in Fig. 1. FIG. 4 is a perspective view showing a floating head device according to an embodiment of the invention, and FIGS. 5 and 6 are side views showing the operating principle of the device shown in FIG. 4. In the figure, 1a, 1b, 1c are head elements, 2
a, 2b, 2c are floating surfaces, 6 is a spring, 7 is a magnetic disk as a rotating disk, 8 is an adsorption plate, 9 is a groove, 10
a and 10b are suction surfaces, and 11 is a movable part. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Scope of utility model registration request] The rotary disc side surface of the head supporting movable member facing the recording or reading rotary disc is sloped downward from the fluid inflow side to the fluid outflow side when the rotary disc rotates. A plurality of adsorption surfaces are formed along the direction of the fluid flow, and a levitation force in the opposite direction to the suction force is generated on each adsorption surface by the flow of the fluid. A floating head device comprising a head having a floating effect.