JPS6236786A - Head feeding device - Google Patents

Abstract

PURPOSE:To obtain a head feeding device which can control the head position for a long period with high accuracy and high durability and with a simple and inexpensive structure, by providing a magnetic force generating means at the interlocking part between a lead pin and a screw bar to attract them. CONSTITUTION:A head carriage 3 is supported by a guide bar 4 and a lead pin 5 interlocks a screw bar 2 which is extended from the thickness center part of the carriage 3 and set at a rather lower part. The pin 5 is extended in parallel with the screw groove 2a of the bar 2 and interlocks this groove 2a. While a thin block-shaped magnet 8 is attached at the upper part of the pin 5 with a slight distance secured between them. Here the magnet 8 is fixed onto the lower surface side of an arm 9 extended horizontally from the carriage 3. Then the sucking force is produced between the magnet 8 and the bar 2 and the carriage 3 oscillates toward the direction (a') with the bar 4 defined as a revolving fulcrum to press the pin 5 to the bar 2. Thus the bar 2 interlocks the groove 2a with high accuracy.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a head feeding device, particularly a head that moves a head device used for various processing such as a magnetic head or an image reading head in a straight line relative to an object. Regarding the feeding device.

[Prior Art 1] This type of device, particularly a device for moving a magnetic head in the diametrical direction of a magnetic disk, was constructed as shown in FIG.

A head carriage 3 carrying a magnetic head is penetrated by a round guide bar 4 at two positions and is arranged along the guide bar 4, and this screwper 2 is rotationally driven by a step motor 1. . As shown in FIG. 4, a round bar-shaped lead pin 5 extending horizontally from a side surface near the top of the head carriage 3 engages with the screw groove from above the screwper 2. The lead pin 5 obliquely intersects with the screwper 2 main body in the horizontal plane as shown in FIG.
As shown in the side view of the figure, it engages in parallel with the screw groove 2a.

Further, below the lead pin 5, a pressure spring 6 made of an elastic material such as plastic extends horizontally, and comes into contact with the bottom of the screwper 2 as shown in FIG. Figures 5 and 6
As shown in the enlarged view of the figure, the suppression spring 6 is connected to the screw groove 2.
It is formed wider than a and presses the circumferential surface of the screwper 2. As a result, the head carriage 3 is urged to rotate in the direction a in FIGS. 4 and 6 using the guide bar 4 as a fulcrum, and as a result, the lead pin 5 is reliably engaged in the screw groove 2a.

When the step motor 1 is rotated in this state, the lead pin 5 is guided to the screw groove 2a, and the head carriage 7 is moved by another guide plate 7 to the screw bar 2. It is moved in the A-B direction while maintaining parallel to the guide bar 4.

[Problem to be Solved by the Invention 1] According to the above-described conventional configuration, the lead pin 5 is engaged with the screw groove 2a by the pressing force of the suppression spring 6 against the screwper 2, so that the lead pin-screw Large frictional resistance occurs not only between the bars, but also between the pressing panel screw bars, which have a large contact area. The above configuration has a drawback that the drive hysteresis of the step motor 1 increases during driving due to the frictional force in the carriage movement direction and the screw bar rotation direction. Also, the plastic pressure spring 6 wears out due to this frictional force.
There was also the problem of looseness.

[Means for Solving the Problems] In order to solve the above problems, in the present invention, a head device for performing a predetermined process is configured by a rotating screw bar and a lead pin connected to the head device that engages with the screw bar. In the head feeding device that feeds the head linearly, a structure is adopted in which the engaging portion of the lead pin and the screw bar is provided with a magnetic force generating means for attracting the lead pin and the screw bar to each other.

[Function] According to the above configuration, the lead pin and the screw bar can be reliably engaged without causing unnecessary frictional resistance, and
It is possible to improve positioning accuracy and durability.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

FIG. 1 corresponds to FIG. 6 of the conventional example, and is a front view of a screw bar to dowel pin engaging portion of a head feeding device according to an embodiment of the present invention. Head carriage 3 is a conventional example (Figure 3)
Similarly, it is supported by the guide bar 4. Lead pin 5
extends from the center of the thickness of the helad carriage 3 and engages with the screwper 2 located somewhat lower than in the conventional example. Although the top view is omitted here, the screwper 2
The lead pin 5 extends parallel to the screw groove 2a, and engages with the screw groove 2a as shown in FIG. 2, as in the conventional example.

On the other hand, a thin block-shaped magnet 8 is attached to the top of the lead pin 5 at a short distance.

The magnet 8 is fixed to the lower surface of an arm 9 extending horizontally from the helad carriage 3.

In the above configuration, the screwper 2 is made of a magnetic material such as stainless steel or steel.

As a result, an attractive force is generated between the magnet 8 and the screw bar 2, and the head carriage 3 swings in the direction a' in FIG. Press to ensure engagement with the screw groove 2a.

According to this configuration, since a conventional restraining spring is not used, the frictional force is generated only at the engagement portion between the lead pin and the screw bar. Therefore, it is possible to prevent the hysteresis of the step motor for driving the screw bar from increasing due to unnecessary frictional resistance in the rotational direction of the screw bar and in one direction of the screw bar, as in the conventional case, and enables highly accurate position control. Furthermore, according to engagement using a magnet, the pressing force of the lead pin can be easily set to the desired minimum value by adjusting the distance between the magnets, and since it is not a contact type like a pressing spring, The lead pin can be engaged with a predetermined pressing force over a long period of time. That is, according to this embodiment, a highly durable head feeding device capable of highly accurate head position control can be provided.

The head device moved by the head carriage is not limited to a magnetic head, but may be any other device such as an image reading head.Also, even if the magnet 8 is omitted and the lead pin or screw bar itself is magnetized, fewer parts can be used. A similar effect can be obtained with points.

[Effects] As is clear from the above, according to the present invention, the head device for performing a predetermined process is sent in a straight line by a rotating screw bar and a lead pin connected to the head device that engages with the screw bar. The device adopts a configuration in which the retaining portion of the lead pin and the screw bar is provided with a magnetic force generating means that attracts them to each other, so it is possible to control the head position with high precision over a long period of time with a simple and inexpensive structure. It is possible to provide a head feeding device with excellent durability.

[Brief explanation of drawings]

FIG. 1 shows the glue-dopin of the head feeding device according to the embodiment of the present invention.
Fig. 2 is a side view of the screw bar engaging part from the beam to the dowel, Fig. 3 is a top view of a conventional head feeding device, and Fig. 4 is a conventional head feeding device. FIG. 5 is a side view of the lead bin-screw bar engaging portion of the conventional device, and FIG. 6 is a front view of the lead pin-screw bar engaging portion of the conventional device. 2...Screw bar 3...Head carriage 5
...Lead pin 8...Magnet 9...Arm

Claims (1)

[Claims] In a head feeding device that linearly feeds a head device by a rotating screw rod and a lead pin coupled to the head device that engages with the head device, a magnetic force generating means is provided to maintain engagement between the lead pin and the screw rod. A head feeding device featuring: