JPS59187155A - Rotary motion converting device - Google Patents

Abstract

PURPOSE:To prevent over-rotation of a spindle under permitting the spindle to rotate the rotation of 360 deg. or more by a method wherein an over-rotation preventing machanism, restricting the rotation of a pulley to rotate less than a predetermined rotating number under permitting one rotation or more, is provided between a motor and the pulley. CONSTITUTION:The step motor 1 is provided with a pin 9 located at a position having a predetermined distance from a motor shaft 20 in the circumferential direction thereof and the spindle 4, having the pin 5 projected from a surface opposing to the motor 1, is secured to the motor shaft 20. A racing plate 10, formed stepwisely with surfaces A, B engaging with the pin 9 and the surfaces C, D engaging with the pin 5, is mounted rotatably on the shaft 20 at a place between the motor 1 and the spindle 4. According to this method, the pulley 4 is permitted to make a rotary motion more than one rotation up to two rotations by a relation of angles between the faces A, B, C, D of the racing body 10 and the rotating center thereof as well as the diameters of the pins 5, 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a rotary motion converting device, and particularly to a rotary motion converting device having an over-rotation prevention function and suitable for a positioning mechanism of a magnetic head in a magnetic disk device.

1 [Background of the Invention] In general, a magnetic disk device uses a belt for rotational movement of a step motor to mount a magnetic head. It is equipped with a rotary motion conversion device that converts the carriage into linear motion.

An example of this motion conversion device is shown in FIG.

The rotary motion conversion device shown in FIG. 1 includes a step motor 1 that rotates and stops in response to a drive signal, a tongue 3 of a mounting bracket 2 that fixes the step motor 1, and a shaft 20 of the step motor 1. a pulley 4 directly connected to the
A stopper bottle 5 is fixed to the pulley 4, a thin belt 6 is wound around the outer circumference of the pulley 4, and converts the rotational motion of the motor into linear motion;
0 and a magnetic helad carriage 8 driven in the radial direction. In this rotary motion conversion mechanism, when the step motor 1 goes out of control for some reason, the magnetic helad carriage 8 is driven out of the predetermined movement area, and a base (not shown) that supports each mechanism, etc. In order to prevent the belt 6 from colliding with the belt 6 and breaking due to the impact force, it is necessary to limit the rotation angle of the step motor shaft to a certain amount. For this purpose, a stopper pin 5 fixed to a pulley 4 directly connected to the shaft 20 of the step motor 1 is provided. The pin 5 controls the rotation angle of the shaft 100 by coming into contact with the tongue 3 of the mounting bracket 2. In this case, since the rotation of the pulley 4 itself is prevented, the rotational torque of the step motor 1 is reduced by the stopper pin 5 and the tongue portion 3, and no abnormal tension is applied to the belt 6.

However, in this system, the pulley 4 directly connected to the shaft 20 of the step motor 1 can rotate more than one revolution, and furthermore, depending on the width of the tongue portion 3 and the diameter of the stopper pin 5, the shaft 10 is limited to approximately Δ rotation. Therefore, depending on the rotational angle pitch of the step motor 1 and the radius of the pulley 4, which are determined from the required feed pitch of the carriage 80, there is a drawback that the carriage 8 may not be fully zeroed.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks, and to provide a rotary motion converting device that allows a spindle to rotate over 360 degrees and has an over-rotation prevention function.

[Summary of the invention]

In order to achieve the above object, the present invention provides a 11L motor shaft! The present invention is characterized in that it is provided with a kinetic force converting means that converts a quadruple rotation motion into a kinetic force of one revolution or less, and a movement preventing means that prevents this movement when the kinetic force converting means moves by a predetermined amount.

[Embodiments of the invention]

An embodiment of the present invention will be described in detail below with reference to FIGS. 2 to 4.

Fig. 2 is a diagram showing the main parts of the rotary motion conversion device according to the present invention, Fig. 3 is a diagram showing the positional relationship between the idle rotating plate and the bottle in Fig. 2, and Fig. 4 (a) 2 to 3C are diagrams illustrating the operation of the converting device shown in FIG. 2.

The rotary motion conversion device shown in FIG.
A step motor 1 which performs a rotational movement of 0 and has a bin 9 disposed at a position extending a predetermined distance from the motor shaft 20 in the circumferential direction; and the motor shaft 20.
a spindle 4 having a pin 5 protruding from a surface facing the motor 1; and a shaft 20 rotatably mounted between the motor 1 and the spindle 4 and engaged with the pin 9 of the motor The idling plate 10 is provided with surfaces A and B that engage with each other, and surfaces C and D that engage with the pin 5 of the spindle 4 that are formed in a stepped manner. It should be noted that the motion converting device (not shown) includes a belt, a carriage, etc., as in FIG. 1.

The structure of the idling plate 10 and the positional relationship of the bins 5 and 9 will be explained using FIG. 3.

As shown in FIG. 3, the idling plate 10 includes a circular body portion 10a having a radius Rz with the shaft 20 as the center, and a first protrusion portion that protrudes from a part of the outer periphery of the circular body portion 10a with a radius R2. 10b, and further a radius H2 from the first protrusion 10b.
and a second protrusion 10C protruding with the first
The second protrusion 10b forms side wall surfaces C and D, and the second protrusion 10c forms side wall surfaces A and B. Further, the pin 9 fixed to the step motor 1 is located at a radius of 4 (L3) ) (,4':>Rz) from the shaft 20, and the pin 5 of the pulley 4 is
Radius R5 from shaft 20 (R2>R5>R1)
It is located at the location of Therefore, the side walls C and D of the first protrusion 10b of the idling plate 10 are rotated so that the bin 5
The side walls A and B of the second protrusion 10c are arranged so as to contact only the bin 9 from the rotation ζ thereof.

Therefore, the rotation of the shaft 10 of the male step motor 1 in the clockwise direction (arrow E) is caused by the side wall B of the second protrusion 10C of the idle rolling body 10 pressing against the bottle 9, as shown in FIG. 4(a). At the same time, the pin 5 of the pulley 4 presses the side wall C of the first protrusion 10b. When the shaft 20 rotates in the direction of arrow F from this state, the bin 5 of the boo 94
As shown in FIG. 4(b), it rotates in synchronization with the pulley 4 and moves to a position where it presses the side wall of the first protrusion 10b. When the pulley 4 further rotates in the direction of arrow G, the bottle 5 presses the second protrusion 10b and rotates the idle rolling body 10 counterclockwise, so that the second The idling body 10 rotates until the opposite side wall A of the protrusion 10C presses the bottle 9. Therefore, the idle rolling body 10 is
) and the condition shown in FIG. 4(C), approximately 1.7 rotations are allowed.

In the actual rotation 1j, an example has been shown in which approximately 1.7 rotations of the idle rolling element 1o are allowed, but the present invention is not limited to this. On the other hand, depending on the relationship between B, C, and D and the diameter of the stopper bin 92F1 or 5, rotational movement of one or more rotations and less than two rotations is possible.

In addition, in this embodiment, there is a
By providing two idle rolling elements, the rotation of the bobbin is allowed to be within 2 rotations, in other words, the rotation of the pulley is suppressed to within 2 rotations IM1.
Although the present invention is not limited to this example, it is possible to suppress the rotation of the boot within an arbitrary number of rotations by providing a plurality of idling bodies between the boot and the motor. fi
It also includes those that do lJ.

Further, in the above embodiment, an example was shown in which the motor shaft was provided with an idling body, but the present invention is not limited to this. As shown in FIG. 5(b), which is the -X cross section, the motor shaft 20
A small gear 50 rotates together with the small gear 50, a large gear 51 having a stopper pin 52 on its side, and a large gear 51 that supports the dog gear 51.
This mechanism includes a support stopper portion 60 that prevents rotation of the stopper bin 52 when it comes into contact with the rotation t of the large gear 51. The pulley 4 is 1 due to the gear ratio of the gear 51.
The gear 51 is rotated in the direction of the arrow E.
Or even if it rotates in the F direction, the support stopper part 60
The rotation speed can be suppressed within an arbitrary number of rotations.

In this mechanism, the allowable rotation range of the pulley 4 can be arbitrarily set by changing the gearing. It's just that the above example is
While the load on the motor changes slightly depending on whether the idling body is suppressed or not pressed, this embodiment has the effect that the load on the motor does not change because the load is always applied by the gear. has. Furthermore, although gears are used in this embodiment, the rotational drive may be transmitted between two rotating bodies (one gear and the other) using a belt, for example.

FIG. 6 is a diagram for explaining still another embodiment of the present invention. This rotary motion conversion device includes a motor shaft 20
(This is fixed in the axial direction of the shaft 2o.A gear 63 having teeth along this axis engages with the teeth of the gear 63 to perform linear movement while being kited by the kite rail 61.)
64. :! : It is composed of support stoppers 6o and 771 which support the kite rail 61 and prevent movement of the movable body 64 in the directions of arrows H and 771. In "Embodiment 1," the rotation of the shirt r20 is adjusted to the ratio of the gears of the gear 63 and the moving body 64 (by converting the movement ratio), the rotation of the shaft V is allowed to rotate more than one rotation, and the ratio Rotation is suppressed within the number of times.

〔Effect of the invention〕

As described above, according to the present invention, in a rotary motion converting device, there is provided a rotary motion converting device between a motor and a boot. The over-rotation prevention mechanism, which allows the pulley to rotate more than one revolution and suppresses the rotation within a predetermined number of times, is activated to prevent the motor from running out of control.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating a rotary slide converter for a magnetic disk device according to prior art F. Fig. 2 is a diagram showing the required EiB of an embodiment of the rotary motion converting device according to the present invention, and Fig. 3 is a diagram for explaining the groove structure and arrangement t of the rotating body and the bottle in Fig. 2. Figures 4(a) to 4(C) show the "vesical closure" function of the rotary motion conversion device of FIG. 2. Figures 5(a) and (b) and FIG. It is a diagram showing the main parts of the rotary motion conversion device according to the embodiment of the song. Explanation of the number 1... Step motor 2. Mounting bracket 3... Tongue-shaped part of the mounting bracket 4... Pulley 5... Stotsunogubin
6... Bell 1 7... Recording medium
8... Magnetic helad carriage 9... Stopper bin
10...Patent attorney who represents the spinning board Akio Hashi 1st mouth 46 20th 3rd 5th 4th prisoner (0-)

Claims (1)

[Claims] A rotary motion conversion device comprising: a motor that rotationally drives a motor shaft; a boot that rotates in synchronization with the motor shaft; and a motion converter that converts rotational motion of the boot into linear motion. momentum converting means for converting the kinetic force of one rotation into the kinetic force of one rotation or less;
1. A rotational motion converting device comprising: a movement preventing means for blocking the movement of the momentum converting means when the momentum converting means moves by a predetermined amount.