JPH0191378A - Carriage driving mechanism for floppy disk driver - Google Patents

Abstract

PURPOSE:To eliminate a play between a screw pin and a screw pressing spring by setting the positions of the screw pin and the screw pressing spring which are in contact with one-side surface of a lead screw and the surface of the same on the other side respectively so that said positions are shifted from each other at least a length of one pitch of the lead screw in its axial direction, and thus providing a carriage a moment perpendicular to a guide rail. CONSTITUTION:A magnetic head is mounted on a carriage 1 (not shown in the figure) through which the guide rail 3 runs, and on the one-side part of the carriage, the lead screw 2 parallel with the guide rail 3 is disposed, and the carriage 1 is made move in relation to a floppy disk (not shown in the figure) by the rotation of the screw 2. Accordingly, the screw pressing spring 4 and the screw pin 5 juts out respectively from the front and the rear surfaces of the carriage 1. The lead screw 2 is pinched at its own inner and outer surfaces by the tip parts of them 4,5. The spring 4 and the pin 5 are made shifted from each other at least one pitch of the spiral groove provided in the screw 2 in facing to each other. As a result, a moment is generated between the carriage and the rail perpendicular to the guide rail.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a carriage drive mechanism for a floppy disk drive.

[Conventional technology]

2. Description of the Related Art Floppy disks, which are flexible disks with a magnetic recording coating applied to their surfaces, are well known and have been widely used as simple magnetic recording media in recent combinators. In order to perform desired writing/reading on this type of floppy disk, information is written/read by rotating the floppy disk and moving a magnetic head carried by a carriage to a predetermined track. Drive is well known.

The carriage drive mechanism of a conventional floppy disk drive will be described below with reference to the drawings.

3 to 5 are perspective views showing the main parts of a conventional carriage, and FIG. 6 is a sectional view of the main parts of the carriage.

In each figure, a carriage 1 carrying a magnetic head (not shown) is mounted on a floppy disk by rotating a lead screw 2 which is directly connected to a stepping motor (not shown) and is parallel to a guide rail 3. (not shown). The lateral pressure spring 7 is arranged between the carriage 1 and the guide rail 3. Third
As shown in the figure and FIG. 4, the lateral pressure spring 7 is
It is fixed by a set screw 52. Then, it comes into pressure contact with one guide rail 6, and presses the carriage 1 in the direction of the other guide rail 6. This eliminates backlash that occurs between the carriage 1 and the guide rail 6. Further, in FIG. 3, the lateral pressure metal 6 engaged with the lateral pressure spring 7 presses the carriage 1 in a slidable manner with low friction without bringing the lateral pressure spring 7 into direct contact with the guide rail 3.

The screw presser spring 4 and screw pin 5 shown in FIGS. 5 and 6 are respectively attached to the carriage 1 by a set screw 56.
．． 54, and clamps the lead screw 2. The screw pin 5 engages with the groove of the lead screw 2 and has the function of converting the rotation of the stepping motor into linear reciprocating movement of the carriage 1.

As is clear from the above explanation, the carriage 1 has the lateral pressure spring 7
The guide rail 6 is pressed by the screw presser spring 4, and the lead screw L-2 is pressed by the screw presser spring 4. A lead screw 2 in which a screw pin 5 fixed to a protrusion of the carriage 1 with a set screw 54 is directly connected to a stepping motor.
The carriage 1 can be moved back and forth in response to the rotation of the carriage 1.

[Problem that the invention seeks to solve]

However, when the carriage is made thinner and smaller, the guide rail hole of the carriage and the magnetic head support are close to each other, making it extremely difficult to create the required space between the carriage and the guide rail for a spring with the spring constant required for the lateral pressure spring. Problems have arisen in terms of parts arrangement, such as the problem that it becomes difficult to install the lateral pressure spring, and the thickness necessary for processing the screw holes for fixing the lateral pressure spring.

The purpose of the present invention is to eliminate the lateral pressure spring by giving other parts the same effect as the lateral pressure spring, reduce the number of parts, and reduce the screw hole machining process, thereby creating a small and inexpensive floppy disk drive. An object of the present invention is to provide a carriage drive mechanism.

[Means for solving problems]

In order to achieve the above object, the present invention provides a screw pin that abuts on one side of the lead screw and a screw presser spring that abuts on the other side of the lead screw. By setting the guide rails in a staggered manner, a moment perpendicular to the guide rails is applied to the carriage, thereby eliminating backlash that occurs between the carriage and the guide rails.

〔Example〕

Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is a perspective view of a main part of a carriage drive mechanism showing one embodiment of the present invention, and FIG. 2 is a sectional view showing the direction of rotational moment applied to the carriage in the direction of arrow A in FIG.

In the figure, the screw presser spring 4 is a cantilevered plate spring, and its fixed end is attached to the carriage 1 by a set screw 51.
is fixed. The carriage 1 slides along this guide rail B.

A screw pin 5 provided on the carriage 1 is engaged with and pressed into the groove of the lead screw 2. The predetermined deflection is given to the thread of the lead screw 2 on the side opposite to the groove in which the screw pin 5 is in pressure contact with the screw presser spring 4 at a position one thread away from the position where the screw pin 5 is in contact. Pressure is applied.

Therefore, a counterclockwise rotational moment is applied to the carriage 1 as shown in FIG. 2 by a pair of forces F1 and F2 whose lines of action are shifted as a reaction force from the lead screw 2. By making partial contact with the guide rail 6 as shown in the figure, the guide bushes 8 and 9 that have been attached can be moved between the guide rail 6 and the carriage 1 even without the side pressure spring 7 as shown in FIGS. 3 and 4. The looseness can be removed.

With the above configuration, when lead screw $-2 rotates,
As the screw pin 5 receives the rotation, the carriage 1 moves along the guide rail B a distance corresponding to the rotation angle without play.

In the above, an example was introduced in which a plate spring with a tapered tip was used as the screw presser spring, and the displacement amount with respect to the screw pin was one peak. However, the shape and structure of the screw presser spring and the screw pin are limited to this example. Instead, any structure that produces an equivalent effect may be used. For example, the tip of the presser spring may have a pin shape instead of a flat plate shape, and may engage with the screw groove on the opposite side of the screw pin.

Also, the amount of shift of the contact position (strictly speaking, the center Fl and F2 of the pressing reaction force acting on the screen pin and screw groove spring)
Practically speaking, the distance between the line of action of 1 ridge is appropriate, but it can also be achieved with solder, for example, and if it is 2 to 3 ridges or more, the anti-backlash force can be increased even further. Can be done.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the backlash between the carriage and the guide rail can be removed without using a lateral pressure spring due to the rotational moment generated by the screw presser spring and the screw pin. It has become possible to eliminate the need for screws and set screws, and at the same time, it has become possible to find room in the mounting space for parts of the carriage, resulting in an increased degree of freedom in design and a carriage drive mechanism that is effective in reducing costs and downsizing.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of a carriage drive mechanism showing an embodiment of the present invention, and FIG. 2 is a part of the mechanism that removes backlash between the carriage and the guide rail by the generation of rotational moment in the direction of arrow A in FIG. The sectional view and FIGS. 3 to 6 show a conventional example, FIGS. 3 and 4 are external perspective views showing the main parts of the lateral pressure spring attached to the carriage, and FIG. 5 shows the screw presser spring. FIG. 6 is a partial perspective view showing the main part of the carriage when it is attached to the carriage, and FIG. 6 is a sectional view of the main part of the carriage. 1... Carriage, 2... Lead screw, 6... Guide rail, 4...
...Screw retainer spring, 5...Screw pin, 6...Side pressure metal, 7.
...Side pressure spring, 8.9...Guide bush, 51.52.56.54...Stop Figure 1
lh Hussoe Figure 3

Claims (1)

[Claims] In the carriage drive mechanism of a floppy disk drive in which a carriage carrying a magnetic head is slidably supported on a guide rail and driven by a lead screw stepping motor, a screw pin that abuts one side of the lead screw and the other side of the lead screw are used. A moment perpendicular to the guide rail is applied to the carriage by setting the abutting position of each of the screw presser springs that abut on the side of the lead screw to be shifted by at least one thread in the axial direction of the lead screw. Carriage drive mechanism of floppy disk drive.