JPS63104250A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To make the titled device small in size, light in weight and to improve the reliability by adopting the constitution such that a motor control means drives a motor till a detection means detects a mode when a preset mode is selected. CONSTITUTION:When the reproducing mode is selected by a mode selection means, a motor control means calculates a motor drive angle required to drive a cam disk 8 for an angle corresponding to the reproducing state, e.g., 205 deg. from the preceding mode and the selected mode and drives the motor 2 in the calculated direction. Then the motor 2 is stopped according to a motor control signal. Then the disk 8 is driven by 205 deg. and a moving member 9 is moved in the direction of an arrow A together with a cam follower 10 and stopped. As a result, the reproducing mode is attained. In selecting other mode such as fast winding or rewinding mode, the above processing is applied. Through the constitution above, a switch group detecting the arrival of each mode is abolished, malfunction due to improper contact is prevented and the small size and light weight for the device are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording and reproducing device that can be used in video tape recorders (hereinafter abbreviated as VTR) and the like.

2. Description of the Related Art In recent years, as means for switching the operating mode of a magnetic recording/reproducing apparatus, a method has been developed that uses a moving member that rotates a cam with a motor and moves to a plurality of positions following the cam. For example, as shown in Japanese Patent Application No. 57-30974, the displacement of the moving member is controlled by the output of the switch group, which is equipped with a switch group consisting of a plurality of brush-like contacts that rotate in synchronization with the rotation of the cam. It was detected.

Problems to be Solved by the Invention However, this method requires a group of switches in addition to the motor and cam, which is an obstacle to making the circuit smaller, lighter, and more reliable. It had become.

In addition, magnetic recording/reproducing devices generally have many types of operation modes, and as a result, the configuration of the switch group tends to be complicated, which has the disadvantage of making it difficult to miniaturize the switch group. .

Furthermore, since the switch group has brush contacts, there is a possibility that poor conduction may occur due to sliding wear.

It is also possible to consider a configuration in which a moving member is attached to the motor via a worm gear to switch the operating mode of the device without having a cam part, but even in this configuration, it is necessary to attach an operating mode detector to the moving member. , which tends to result in extremely complex configurations. In addition, due to assembly errors such as dimensional errors in the nine parts, the operation mode detector may generate false information that the predetermined operation mode has been reached even if the predetermined operation mode has not been reached, or the operation mode detector may generate incorrect information that the predetermined operation mode has been reached. Despite reaching
This may lead to the worst case scenario, in which the predetermined detection signal is not generated and the mechanism of the device is destroyed.

Means for Solving the Problems In order to solve the above problems, the magnetic recording and reproducing apparatus of the present invention includes mode selection means for selecting one mode from a plurality of modes of the magnetic recording and reproducing apparatus; Note tq for storing mode information of the mode selected by the means
a motor control means that generates a motor control signal according to a mode selected by the mode selection means and a mode before being selected; and a motor that rotates by a rotation angle corresponding to the motor control signal. a mode switching means for switching the mode of the magnetic recording/reproducing apparatus by moving to a plurality of positions according to a rotation stop position of the motor; and a mode switching means for switching the mode of the magnetic recording/reproducing device by moving to a plurality of positions according to a rotation stop position of the motor; and detection means for detecting the set position.

Effect of the present invention With the above-described configuration, depending on the mode selected by the mode selection means and the mode before being selected,
The absolute rotation of the motor is calculated by calculating the number of rotations required for the motor, rotating the motor by the required number of rotations, and detecting when the mode switching means is located at a preset position. Since the phase can be determined, it is possible to determine the rotation angle of a rotating body that has a cam part that rotates in synchronous engagement with the motor. It can be determined whether or not a predetermined operating mode is achieved.

Furthermore, when the preset mode is entered, the mode information used to calculate the required number of revolutions for the motor is reset, thereby eliminating any electrical or mechanical errors that may have occurred when changing modes many times. can be canceled and the mode transition can be performed without accumulating the error. Therefore, the device can be made smaller and lighter, and it is possible to shift to a highly reliable mode without accumulating electrical or mechanical errors, improve assembly efficiency, and make it possible to switch more complicated operation modes.

EXAMPLE An example of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view of a main part in an embodiment of the present invention. A pulse motor 2 (hereinafter simply referred to as motor 2) that rotates in accordance with an input pulse signal is fixed to the substrate 1. A gear 4 is rotatably and loosely fitted on the motor shaft 3 of the motor 2, and meshes with a gear 6 that is rotatably and loosely fitted on a shaft 5 implanted in the base 11. Furthermore, a cam disk 8 having a cam groove 8a and gear teeth on its outer circumferential surface is loosely fitted into the shaft 7 implanted in the base plate 1. It meshes with the gear portion 6a. Furthermore, a bub 8c having a convex portion 8b is provided on the outer periphery of the cam disc 8.

The shape of the cam groove 8a is such that the distance from the center of rotation is changed in stages as shown in FIG. Following the rotation of the cam disk 8, the moving member 9 moves to a plurality of positions and switches each operation mode of the device. FIG. 3 is a cam curve showing the cam lift amount corresponding to the rotation angle of the cam disk 8 and each operation mode.

Next, the operation of this embodiment will be explained. FIG. 4 is a schematic block diagram of essential parts of this embodiment. First, when the device is at stop B, the rotation angle of the cam disk 8 is stopped at 0'' as shown in FIG. It is in the ON state by being pressed by the convex part.At that time, the cam follower 10
is in the position shown in FIG. 5, and at the position of cam lift 01 in FIG. 3, each member (not shown) of the device, such as the brake, is in a stopped state B. Next, when a reproduction mode is selected by a mode selection means (not shown), a motor control means (not shown) is selected based on the mode information of the mode before selecting the mode, that is, the stop mode, and the selected mode, that is, the reproduction mode. However, the rotation angle of the motor required to rotate the cam disc 8 by 205@ is calculated by considering the reduction ratio from the motor 2 to the cam disc 8, and the motor control signal is generated based on the calculation result. is transmitted to the motor 2, the motor 2 is driven to rotate in the calculated rotation direction, and then the motor 2 is stopped according to the motor control signal. At the same time, the cam disk 8 rotates to 205', and at the same time, the movable member 9 moves together with the cam follower 10 in the direction of arrow A shown in FIG. 1, and stops after moving 6 degrees from FIG. 3.

Each member (not shown) of the fruiting device becomes in a state of reproducing ecology, and the device itself becomes in a state of reproducing ecology.

The state at that time is shown in FIG. In FIG. 6, the convex portion 8b
has already separated from the switch 11, and the switch 11 is in the OFF state.

Next, the mode selection means selects the fast winding/rewinding mode (FF
/Rew), reverse reproduction mode (Review), and reproduction mode (PLAY) are repeated several times, it is possible that some electrical or mechanical error may occur. Therefore, as this error accumulates, for example, when the mode selection means
motor control means (not shown)
Even if it is determined that the rotation angle of the cam disk 8 is calculated by calculating the rotation angle of the cam disk 8, the rotation is stopped after the motor 2 is driven based on the calculated value, and the cam disk 8 is rotated up to 90'', the rotation angle of the cam disk 8 is actually has stopped at 115'', and therefore the moving member 9 has not moved to the predetermined position, which may cause malfunction of the fruiting device.

Therefore, in this embodiment, even if the above-mentioned error occurs, once the mode selection means (not shown) selects the stop mode a, the motor control means (not shown), as described above, If the required rotation angle of the motor 2 is calculated, the motor 2 is rotated by a predetermined rotation angle, and the switch 11 is turned on at that time, it means that the rotation angle of the cam disc 8 is 0°. When the rotation of the motor 2 is stopped and the switch 11 is OFF, the motor 2 is further rotated until the switch 11 is turned ON, and when the switch 11 is turned ON, the rotation angle of the cam disc 8 becomes Oa.
, so motor 2 is stopped. At this time, the mode information of the motor control means (not shown) is reset so that it is currently in the stopped mode.

Also, needless to say, in this embodiment, the mode of resetting is set to the stop a mode, but there is no problem with any mode of resetting. However, in order to minimize the accumulation of electrical or mechanical errors that occur, it is preferable to set the reset mode to the mode that is used most frequently.

Effects of the Invention As described above, the magnetic recording and reproducing apparatus of the present invention includes a mode selection means for selecting one mode from among a plurality of modes of the magnetic recording and reproducing apparatus, and mode information of the mode selected by the mode selection means. a motor control means for generating a motor control signal according to a mode selected by the mode selection means and a mode before being selected; a motor that moves to a plurality of positions according to a rotation stop position of the motor, and a mode switching means that switches the mode of the magnetic recording/reproducing device; detection means for detecting the set position of the mode switching means,
When the mode selected by the mode selection means is one mode set in advance from among the plurality of modes, the motor control means is operated until the mode switching means moves to the set position and the detection means detects the mode. Since the motor is configured to rotate, it eliminates the need for a group of switches to detect when each mode has been reached, and can now be detected with a single point switch.As a result, poor contact due to sliding wear on the switch is eliminated, and malfunction of the device is prevented. It can be prevented. Even if the number of operating modes is increased, the cam disc 80 phase is always known by the mode selection means and motor control means, so the above-mentioned errors do not occur, the size of the device does not change, and design changes regarding modes are possible. There is also a great degree of freedom.

Furthermore, even if the error occurs, the error can be canceled, so malfunction of the device due to accumulation of errors can be prevented. Further, since the cam disk 8 and the motor 2 rotate synchronously via the gear reduction mechanism, there is no relative phase shift between them. Furthermore, even if the rotation of the cam disk 8 is slight, the motor 2 Since the number of pulses of the motor control signal transmitted to the cam disk 8 is large, the rotational phase accuracy of the cam disk 8 becomes extremely accurate.

In addition, during assembly, for example, when the cam disk 8 is stopped and the mode (rotation angle θ°) is set, the cam disk 8 and the motor 2 only need to be given mode information indicating that the cam disk 8 is currently in the stopped mode to the motor control means. There is no need to match the relative rotational position and phase, and assembly can be automated.

Therefore, malfunctions of the device can be prevented, the device can be made smaller and lighter, and the assemblability and reliability can be improved, and more complicated operation H-type switching is also possible.

4. Explanation of the drawings Fig. 1 is a sectional side view of a main part of a magnetic recording/reproducing device according to an embodiment of the present invention, Fig. 2 is a plan view of a cam disk, Fig. 3 is a cam curve diagram, Fig. 4 are schematic block diagrams, Figures 5 and 6.
The figures are plan views of main parts in the stopping mode and the reproducing mode, respectively.

2...Motor, 8...Cam disc,
8a...Cam groove, 9...Moving member, 1
1. Old... Switch.

Name of agent: Patent attorney Toshio Nakao 1 person 2---
E-g 6b f3 a R-s 3 to Erpeng-Breath Figure 4

Claims (1)

[Claims] mode selection means for selecting one mode from a plurality of modes of the magnetic recording/reproducing device; storage means for storing mode information of the mode selected by the mode selection means;
a motor control means that generates a motor control signal according to the mode selected by the mode selection means and a mode before being selected; a motor that rotates by a rotation angle corresponding to the motor control signal; a mode switching means for switching the mode of the magnetic recording/reproducing device by moving to a plurality of positions according to a rotation stop position; and a setting position of the mode switching means corresponding to one preset mode from among the plurality of modes. If the mode selected by the mode selection means is one preset mode from among the plurality of modes, the mode switching means moves to the set position and the detection means detects. A magnetic recording/reproducing apparatus characterized in that the motor control means is configured to rotate the motor until the motor is rotated.