JPH0416291Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention is used in a disk device that records and reproduces information signals by rotationally driving a disk, which is an information signal recording medium, and moving a head in the radial direction of the disk. This invention relates to a head moving mechanism.

(Prior Art) The present applicant has proposed a rotating body that is rotationally driven by the rotation of a driving motor, a spindle hub for disk rotation drive that is rotationally driven by the rotation of this rotating body,
a conversion means for converting the rotational motion of the rotary body into intermittent rotational movement; a cam body that is intermittently rotationally driven by the conversion means; and a cam body that is provided on the cam body and whose diameter changes stepwise. We previously filed a patent application for a disk device that includes a cam portion, a head carriage that engages with the cam portion and moves linearly in the radial direction of the disk, and a head attached to this carriage. (See Application No. 59-68199).

According to the disk device according to the above-mentioned application, since the rotational drive of the disk and the intermittent feeding of the head are performed by one motor, cost reduction and miniaturization have been achieved.

(Problems to be Solved by the Invention) According to the disk device according to the above-mentioned application, the above-mentioned effects are achieved, but the head feeding operation is performed one track at a time by instantaneous operation of a solenoid. Therefore, the operation is slow, and
Because the solenoid moves to the next track with instantaneous action, the structure is complicated, and there were still problems that needed to be resolved.

The present invention was made to solve the remaining problems of the disk device according to the above application, and is a device that converts the continuous rotational force of the rotating body into the intermittent feeding force of the head, and is quick and easy to operate. The object of the present invention is to provide a head movement mechanism of the configuration.

(Means for solving the problem) The present invention includes a continuous rotating body, a connecting rotating body rotationally driven by the continuous rotating body, and a driven rotating body rotationally driven by the connecting rotating body. a cam portion for moving the head whose diameter changes stepwise to correspond to the head stop position; and an engaging portion provided to correspond to the stepwise change in diameter;
A cam body that rotatably holds the coupling rotary body, a lever that selectively engages with the engaging portion of the cam body or the driven rotary body depending on the rotational position, and a solenoid that controls the position of the lever. , a reference position sensor that generates a signal when the head is in the reference position, and a step sensor that generates a signal each time the head moves one step, and the solenoid normally moves the lever to the cam body. The position of the lever is controlled so as to engage with the engaging portion to restrict the rotation of the cam body and rotate the driven rotating body, and when moving the head, the lever is engaged with the driven rotating body. The position of the lever is controlled so as to restrict the rotation of the driven rotary body, and the lever is disengaged from the cam body to rotate the cam body, and the output of the reference position sensor or step sensor is controlled. Based on this, the lever is controlled to return to its normal state.

(Operation) When the lever is engaged with the engaging portion of the cam body, the driven rotary body is simply rotated continuously by the continuous rotary body via the connecting rotary body, and the rotation of the cam body is regulated and the head does not move.
When the position of the lever is controlled by the solenoid so that the lever engages with the driven rotary body, the cam body is rotationally driven by the continuous rotary body via the connecting rotary body, and the head is moved. A reference position sensor provides a signal when the head is in the reference position, and a step sensor provides a signal each time the head moves one step. Based on the output of the reference position sensor or step sensor, the solenoid returns the lever to its normal state, restricts the rotation of the cam body, and stops the movement of the head.

(Example) First, a first example shown in FIGS. 1 to 9 will be described.

In FIG. 1, a bearing 108 is fitted and fixed on the lower surface side of the chassis 42, and the shaft portion of a spindle hub 105 is rotatably supported by the inner periphery of the bearing 108. A small diameter gear 10 is attached to the shaft portion of the spindle hub 105 that protrudes from the lower end of the bearing 108.
A rotary body 103 is fitted and fixed to the boss of the gear 104. The outer periphery of the rotating body 103 is a pulley portion, and the belt 102 is hung on this pulley portion. Belt 102 is also placed over pulley 101 of motor 100 as shown in FIG.
As long as the rotating body 103, the gear 104, and the spindle hub 105 are rotationally driven, the rotating body 103 is a continuous rotating body.

A hole 106 is formed in the center of the spindle hub 105 for receiving the lower protrusion 5 provided in the center of the disk hub 4. A protrusion 107 is formed to engage with the disk 7 and rotate the disk 3 .

A cam body 109 for moving the head carriage is rotatably fitted on the outer periphery of the bearing 108. A cam groove 110 for moving the head carriage is formed on the upper surface side of the cam body 109. As shown in FIG. 2, the cam groove 110 is formed in 17 stages by dividing the cam body 109 into two half-circumferentially, and the distance from the center of each half changes stepwise. A mesial portion of the cam groove 110 formed on one half circumference and a distal portion of the cam groove 110 formed on the other half circumference are connected to each other by a connecting groove 111.

In FIGS. 1 and 2, locking recesses 112 are formed on the outer periphery of the lower surface of the cam body 109 in correspondence with each step position of the cam groove 110, and the center of the cam body 109 and the outer periphery are Annular protrusion 1 in the middle part
14 is formed, and a downward protruding pin 113 is formed in a part of the annular projection 114. The pin 113 is connected to the gear 1 as shown in FIGS. 1 and 3.
15 is rotatably fitted, and the annular projection 114
An annular gear 116 is rotatably fitted on the outer periphery of the ring. The gear 115 includes an inward gear 119 formed on the inner circumference of the annular gear 116 and a small diameter gear 104.
It engages both sides. As shown in FIG. 3, ratchet tooth-shaped engagement gears 118 are formed on the outer periphery of the annular gear 116, corresponding to each stage of the cam groove 110.

The gear 115 serves as a connecting rotating body that is rotationally driven by the rotating body 103, and the annular gear 116 serves as a driven rotating body that is rotationally driven by the gear 115 as the connecting rotating body.

In FIGS. 3 and 4, a bell crank-shaped control lever 120 is located on the side of the cam body 109.
It is provided so as to be rotatable around 23. A permanent magnet 124 is fixed to the edge of one arm of the lever 120, and the magnet 124 and the iron core 1 of the solenoid 125 are connected to each other.
26, the lever 120 is urged to rotate counterclockwise in FIG.
It enters into the locking recess 112 of No. 09 and engages therewith. On the other hand, the other hook-shaped arm end 122 of the lever 120 faces the engagement gear 118 on the outer periphery of the annular gear 116, but is normally spaced apart from the engagement gear 118.

FIG. 4 shows the configuration of the solenoid 125. The solenoid 125 includes a case body 127 and a coil 13.
2 and an iron core 126, the case body 12
The coil 132 is fitted into the space between the coil attachment protrusion 128 at the center of the coil attachment protrusion 128 and the cylindrical portion surrounding it, and the coil 132 is fitted into the center hole 13 of the coil attachment protrusion 128.
0 and a horseshoe-shaped iron core 1 in the hole 131 provided on the side.
26 are fitted and fixed. Hook-shaped attachment portions 129 are formed on both sides of the case body 127.
The solenoid 125 is attached to the chassis by this attachment portion 129, and the iron core 126 faces the permanent magnet 124.

Next, the operation of the cam body 109 will be explained with reference to FIG. Together with the continuous rotating body 103 (see FIG. 1), the small diameter gear 104 is driven to rotate in the direction of arrow H, and the gear 115 is driven to rotate in the direction of arrow I. Here, since the one arm end 121 of the control lever 120 normally enters and engages with the locking recess 112 of the cam body 109, rotation of the cam body 109 is prevented, and
Since the other arm end 122 of the control lever 120 is separated from the engagement gear 118 of the annular gear 116 and the annular gear 116 is free, the gear 115
Due to this rotation, the annular gear 116 is rotationally driven in the direction of arrow J via the inward gear 119. That is, normally, the annular gear 116 only rotates continuously, the cam body 109 does not rotate, and the position of the head carriage does not change.

To change the position of the head carriage, energize the coil 132 of the solenoid 125 to
6 excites the permanent magnet 124 so as to repel it.
As a result, the control lever 120 rotates clockwise in FIG.
9, the other arm end 122 of the lever 120 engages with the engagement gear 118 of the annular gear 116, and the cam body 109 becomes rotatable, whereas the annular gear 116 cannot rotate. thwarted.
Therefore, as the gear 115 is rotationally driven in the direction of the arrow I, the downward protruding pin 113 of the cam body 109 is rotated in the direction of the arrow K.
The cam body 109
is rotated in the direction of arrow L. When the cam body 109 rotates, the position of a guide pin 159 (described later) fitted in the cam groove 110 moves in the radial direction of the cam body 109, and the head carriage also moves accordingly.

In FIG. 5, reference numeral 151 is a carriage for supporting the head.
51 is connected to the head 15 via a gimbal plate 153.
4 is supported so as to be swingable within a predetermined range.
Partially cylindrical pin receiving parts 155 and 156 are formed on one side edge of the carriage 151, and when the carriage 151 is attached to the chassis, the pin receiving parts are attached to the support pins 160 and 160 fixed to the chassis. The carriage 151 is supported by the contacts 155 and 156 coming into contact with each other from above. The other side edge of the carriage 151 is also supported by a pin 161. A cut-and-raised portion 157 is formed on the carriage 151, and this cut-and-raised portion 15
The carriage 151 is biased downward and in the radial direction of the disk by the elasticity of a spring 162 applied between the carriage 7 and the chassis. The flat surface of the carriage 151 is lightly pressed with an uncircumfered pin fixed to the chassis from above to prevent the entire carriage from floating up.
A guide pin 159 is installed at the tip of the carriage 151.
is provided, and this pin 159 engages with the cam groove 110 to move the head carriage 151. The carriage 151 is formed with a cut-and-raised portion 163 for attaching another head carriage (not shown). Another carriage attached to this cut-and-raised portion 163 supports another magnetic head or pad in the same way as the above-mentioned carriage 151, and this magnetic head or pad and the magnetic head 154 supported by the carriage 151 are attached to the disk. It is designed to make sliding contact by sandwiching it.

In FIGS. 3 and 5, a head position detection lever 135 is rotatably supported on the side of the cam body 109 about a shaft 143. As shown in FIGS. Detection lever 1
A pin 139 is firmly planted on the free end of the lever 135, and a switch contact piece 140 is pressed into contact with the pin 139, and the spring force of the switch contact piece 140 causes the lever 135 to move its hook-shaped free end 137 into a cam. body 1
It is urged to rotate in the direction of contacting the locking recess 112 of No. 09. The free end 137 of the lever 135 is
The guide pin 159 of the head carriage is in the cam groove 1.
10, when the head 154 is in sliding contact with the first track on the outermost circumference of the disk 3, the locking recess 1 corresponding to the first track
12a. This locking recess 112a is formed continuously with a recess 136 for detecting return to original position. The locking recess 112a is formed to the same depth as the other locking recesses 112, but the home position return detection recess 136 is
It is formed deeper than 2. The free end 137 of the detection lever 135 is connected to the locking recess 112,
112a, the switch contact piece 14
0 is separated from the switch contact pieces 141 and 142 on both sides, and when the free end 137 of the lever 135 falls into the detection recess 136, the contact piece 140 contacts the contact piece 142 and the cam body 109 returns to its original position. free end 137 of lever 135 .
When the contact piece 140 rides on the protrusion 138 between the locking recesses 112, the contact piece 140 comes into contact with the contact piece 141. Here, the contact piece 140 and the contact piece 141
constitutes a step sensor that generates a signal each time the head moves one step, and the contact pieces 140 and 142 constitute a reference position sensor that generates a signal when the head is at the track 00 position, which is the reference position. Eggplant.

In FIG. 5, the guide pin 159 is located at the outermost position of the cam groove 110, and the head position detection lever 135 is
shows a state in which the locking recess 112a is located at the position corresponding to the first track next to the home position return detection recess 136. From this state, the cam body 109 is intermittently driven so that the protrusion 13 between the locking recesses 112
8, each time the cam body 109 rotates, the guide pin 159 is rotated by one tooth on the mesial side of the cam edge of the cam groove 110.
As a result, the sliding contact position of the head 154 with respect to the track of the disk 3 is shifted one step at a time to the track on the inner circumferential side. Cam body 109
Each time the protrusion 138 rotates by one tooth, the switch contacts 140 and 141 come into contact and a signal is emitted from the step sensor 182. By counting this signal, it is determined that the head 154 is in sliding contact. It is possible to detect the track number of the current track.

When the free end 137 of the detection lever 135 is engaged with the recess 136 for detecting return to original position, the switch contacts 140 and 142 come into contact and a signal is emitted from the reference position sensor 181. It can be detected that the cam body 109 is at the reference position, that is, that the guide pin 159 is engaged with the connecting groove 111 that connects the two cam grooves 110. In this way, head 1
Since the sliding contact position of step sensor 182 is always detected, the signal from step sensor 182 is counted, and
By detecting the signal from the reference position sensor 181, the head 154 can be brought into sliding contact with a desired track.

Next, an example of a control block that can be used in the above disk device will be explained with reference to FIG.

In FIG. 6, the disk device is controlled by an external controller, and signals from the external controller are input to an interface 183 via a bus, and are input to a control circuit 184 via an internal bus. be done. Control circuit 184
In response to instructions from an external controller, the controller outputs control instruction signals to the recording/reproducing circuit 185, motor control circuit 186, solenoid drive circuit 187, etc. to control the respective circuits. Motor control circuit 186
When the power is turned on, the motor 100 is constantly driven to rotate. The movement of the head 154 is controlled by the solenoid 125 via the solenoid drive circuit 187.
This is done by driving the . The above control circuit 1
84 includes a step control section 188 for controlling the movement of the head.
The output from the track 00 sensor 181 as a reference position sensor and the output from the step sensor 182 are input to the track register 189 located at 8, and the current track position signal is held in the track register 189. More specifically, the value of the track register 189 is set to a predetermined data content by the output of the track 00 sensor 181, and the data content is added each time the output of the step sensor 182 is added.

The target track to which the head seeks is given by control circuit 184, and its contents are stored in data register 190. This data register 19
The contents of 0 and the contents of the track register 189 are compared in a comparison section 191, and if they match, the energization to the solenoid 125 is turned off.

7 through 9 illustrate the operation of the control block described above. When the power is turned on, the head is moved to track 00 to initialize the device, but at this time, as shown in Figure 7, after turning on the solenoid, the head is moved until the on signal from the track 00 sensor is received. continues to excite the solenoid, turns off the excitation of the solenoid in response to the falling signal of the track 00 sensor, and once energizes in the opposite direction, switches. By doing this, solenoid 1
The state of the lever 120 (see FIG. 3), whose position is controlled by the lever 25, can be reliably switched, so that the seek operation of the head can be performed reliably, and the operation can be easily controlled. To advance one track, as shown in Figure 8,
The solenoid continues to be excited until the ON signal is input from the step sensor. In this way, the solenoid is turned off after it is detected that the cam for moving the head has rotated reliably. In this case as well, in order to reliably switch the state of the lever 120, the solenoid is temporarily energized in the opposite direction.

When moving the head from a given track to n tracks, the solenoid is kept energized until n ON signals are input from the step sensor, as shown in FIG. In this way, when it is detected that the head moving cam has rotated by an angle corresponding to n tracks, the solenoid is turned off. In this case as well, the solenoid is temporarily energized in the opposite direction.

Note that if a mechanism such as that shown in FIG. 13, which will be explained later, is used, it is not necessary to energize the solenoid in the opposite direction.

Next, with reference to FIGS. 10 to 13, another example of a disk rotation drive mechanism and a head movement mechanism that can be used in the present invention will be explained with emphasis on the differences from the mechanism according to the previous embodiment. Explain in detail.

In FIGS. 10 and 11, the cam body 201
A cam groove 200 is formed in stages so as to make the head reciprocate once per revolution, and further,
A locking recess 202 is provided around the cam body 201 so as to correspond to each stage position of the cam groove 200. On the lower surface side of the cam body 201, an engagement gear 204 and an inward gear 2 are provided on the lower surface side of the cam body 201, as in the previous embodiment.
05 is mounted for relative rotation. In this example, a support plate 207 is provided integrally with the rotating shaft to support the cam body 201, and a roller 207 is provided on the protrusion 208 of the cam body 201 to support the annular gear 203.
9 is provided.

When the track on which the head slides is not switched, that is, when the head is not moved, the cam body 201 is locked non-rotatably, while the inward gear 2
An annular gear 203 by a gear 206 meshing with 05
Rotate. On the other hand, when moving the head to switch tracks, the annular gear 203 is prevented from rotating and the cam body 201 is allowed to rotate, and the cam body 201 is rotated via the gear 206 to determine the track position where the head slides. Switch.

FIG. 11 shows an example of the head moving mechanism. In the example shown in FIG. 11, the control means for selectively rotating one of the cam body 201 and the annular gear 203 and locking the other non-rotatably,
The bell crank-shaped control lever and the solenoid are not separated, but are configured as a rotary solenoid 220 that integrates both. In FIG. 11, a rotating case 211 rotatably supported around a shaft 210 corresponds to a control lever, and the rotating case 211 has an arm end 212 that locks the rotation of the annular gear 203 and an arm end 212 that locks the rotation of the annular gear 203. An arm end 213 that locks the rotation of the cam body 201 is integrally formed with the case 211, and an annular permanent magnet 214 is adhesively fixed to the inner surface of the case 211. In addition, the shaft 21
As shown in FIG. 12, pole plates 215 and 216 made of silicon steel plates are positioned coaxially with
The bipolar plates 21 are arranged opposite to each other with a 90 degree shift.
An excitation coil 217 is wound within the space formed by 5 and 126. The pole plates 215 and 216 having the excitation coil 217 are located inside the annular permanent magnet 214, and the excitation coil 217 is located inside the annular permanent magnet 214.
By energizing 7, the permanent magnet 214, i.e.
The rotating case 211 is rotated in a predetermined direction to control the rotation locking of the annular gear 203 and the rotation locking of the cam body 201.

In this embodiment, when the excitation coil 217 is not energized, the arm end 213 locks the rotation of the cam body 201, and the excitation coil 21
7, the permanent magnet 214 rotates counterclockwise in FIG. 11, and the arm end 212 locks the rotation of the annular gear 203, thereby moving the position of the head.

In the above embodiment, as shown in FIG. 11, in order to detect the track position of the head, a circuit pattern 218 on a flexible substrate and a contact piece member 219 that slides on the surface of this pattern are used.
The flexible circuit pattern 218 includes comb-shaped track patterns 218b of the same shape provided on the circumference so as to correspond to the respective track positions.
, a return-to-home detection pattern 218a provided on the same circumference as the pattern 218b, and a ground pattern 218c provided in a ring shape inside the pattern 218b. The flexible substrate having such a circuit pattern 218 is fixed to the chassis, while the contact piece member 219
is integrally fixed to the cam body 201, and the contact piece member 219
By bringing the contact piece into sliding contact with the pattern surface, the track position of the head can be detected in the same manner as in the first embodiment. Specifically, the contact pieces 219b, 21 integrally formed on the contact piece member 219
The contact piece 9b is always in sliding contact with the ground pattern 218c, and the contact piece 219a integrally formed with the contact piece member 219 is in sliding contact with the same surface on which the original position return detection pattern 218a and the track pattern 218b are formed. Here, the original position return detection pattern 218
a constitutes a reference position sensor, and track pattern 218b constitutes a track sensor.

Also in the case of the second embodiment, the rotational position of the cam body 201 can be controlled by controlling the energization to the coterie solenoid 220, thereby controlling the track position of the disk on which the head slides. I can do it. The control block in this case can also have the same structure as the control block shown in FIG.

The control lever and solenoid may be configured as shown in FIG. In FIG. 13, a control lever 300 is rotatably provided around a shaft 303, and a plunger 306 of a solenoid 305 is pivotally attached to the lever 303 at a position offset from the shaft 303. Plunger 306 is biased by spring 304 in a direction protruding from solenoid 305;
In a normal state in which the solenoid 305 is not energized, the control lever 300 rotates clockwise in the figure due to the biasing force of the spring 304, and one end 301 of the lever 300 engages with the locking recess 202 of the cam body. When the solenoid 305 is energized, the plunger 306 is attracted against the spring 304, causing the lever 300 to rotate counterclockwise, and one end 301 of the lever 300 engages with the locking recess 202. lever 300.
The other end 302 of the annular gear 203 is engaged with the annular gear 203 to stop the annular gear 203 from rotating. If the solenoid and control lever configured in this manner are used, the lever 300 will reliably return to its original position due to the elasticity of the spring 304 when the solenoid 305 is de-energized, so as described in the first embodiment. , it is no longer necessary to turn on the current in the opposite direction after stopping the energization to the solenoid.

The present invention can be used as a head moving mechanism for recording and reproducing apparatuses that use not only magnetic recording disks but also other disks.

(Effects of the invention) According to the invention, the energization of the solenoid for moving the head is canceled based on the output of the reference position sensor or step sensor, so that the head is reliably sent to a predetermined position. Moreover, there is no need to make the cam body into a complicated shape in order to make the head feeding position accurate. Also, the solenoid

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a head moving mechanism of a disk device according to the present invention, FIG. 2 is a plan view of a cam body for moving the head in the same embodiment, and FIG.
The figure is a plan cross-sectional view taken along the line B-B in Figure 1.
The figure is an exploded perspective view of the control mechanism used in the above embodiment, FIG. 5 is a plan view of the head and cam body in the above embodiment, and FIG. 6 is a control block that can be used in the present invention. Block diagram showing an example,
FIG. 7 is a time chart for explaining the operation of the same control block as above, FIG. 8 is a time chart for explaining another operation mode, and FIG. 9 is a time chart for explaining still another operation mode. , FIG. 10 is a longitudinal cross-sectional view showing another embodiment of the head moving mechanism of the disk device according to the present invention;
Figure 1 is a simplified plan view of the same embodiment, and Figure 12 is a simplified plan view of the same embodiment.
The figure is an exploded perspective view showing the structure of the solenoid in the above embodiment, and FIG. 13 is a plan view showing another example of the solenoid and control lever that can be used in the present invention. 103... Continuous rotating body, 115, 206... Connecting rotating body, 116, 203... Driven rotating body, 1
09,201...Cam body, 110,200...Cam part, 112,202...Engaging part, 120,30
0... Lever, 211... Rotating case forming the lever, 125, 220, 305... Solenoid, 181, 218a... Reference position sensor, 1
82,218b...Step sensor.

Claims (1)

[Claims for Utility Model Registration] A continuous rotating body, a connecting rotating body rotationally driven by this continuous rotating body, a driven rotating body rotationally driven by this connecting rotating body, and a head stop position. A cam part for moving the head whose diameter changes stepwise to correspond to the stepwise change in diameter, and an engaging part provided to correspond to the stepwise change in diameter, and the connecting rotary body can be freely rotated. a cam body held at a position; a lever that selectively engages the engaging portion of the cam body or the driven rotating body according to the rotational position; a solenoid that controls the position of this lever; and when the head is at the reference position. Since the head is not sent by instantaneous operation based on the signal generation,
Continuous movement of the head can also be carried out easily, and thus rapid continuous movement of the head can be carried out. It is equipped with a position sensor and a step sensor that generates a signal each time the head moves one step, and the solenoid normally engages the lever with the engaging portion of the cam body to rotate the cam body. The position of the lever is controlled so as to restrict the rotation of the driven rotary body and rotate the driven rotary body, and when moving the head, the lever is engaged with the driven rotary body to restrict the rotation of the driven rotary body and the lever The position of the lever is controlled to release the engagement with the cam body and rotate the cam body, and the lever is controlled to return to the normal state based on the output of the reference position sensor or the step sensor. A head moving mechanism for a disk device characterized by the following.