JP3615879B2 - Magnetic recording / reproducing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to positioning of a standby position of a drawer post of a magnetic recording / reproducing apparatus.
[0002]
[Prior art]
In video tape recorders, there are multiple modes (cassette eject mode, cassette lowering mode, playback mode, reverse playback mode, fast forward / rewind mode) for moving the tape cassette, moving the tape drawer post, and moving the capstan pinch roller. In order to perform proper operation in conjunction with the above, etc., a structure is employed in which each of the above components is driven via a link mechanism that engages with the main cam gear while the main cam gear is rotated by a single DC motor. ing.
[0003]
FIG. 4 shows a configuration for controlling the operation of the motor that drives the main cam gear. The DC motor 1 is connected to the main cam gear 3 via a speed reduction mechanism 2. A link mechanism 5 comprising a main lever 4 (see FIG. 5) that follows a cam groove (not shown) of the main cam gear 3 by rotation of the main cam gear 3, and various levers and gears connected to the main lever 4. Then, the tape cassette raising / lowering driving unit 6, the tape loading driving unit 7, the pinch roller driving unit 8, and the clutch / brake driving unit 9 are driven so as to perform the desired operation at an appropriate time.
[0004]
The main cam gear 3 is connected to a rotary encoder 10 for detecting the rotational position of the absolute value of the main cam gear 3. The microcomputer 11 as a control means receives an instruction input from the operation panel 12 and detection data of the rotary encoder 10. Based on the control, the on / off of energization to the motor, the polarity of energization, and the energization period are controlled so that the main cam gear 3 rotates and stops to the rotation position corresponding to the instruction input from the operation panel 12. Yes.
[0005]
As shown in FIGS. 5 and 6, the tape loading drive unit 7 that draws the magnetic tape from the tape cassette and winds and loads the magnetic tape around the rotary head cylinder 13 has a pair of tape drawing posts 7a and 7b.
[0006]
The tape pull-out posts 7a and 7b, which are slidably engaged with the guide grooves 15a and 15b formed in the chassis 14, are connected to the leading ends of the loading arms 16a and 16b shown in FIG. The proximal ends are connected by pins 19a and 19b to levers 18a and 18b that rotate together with gears 17a and 17b meshed with each other. One of the gears 17a and 17b meshes with a rack 20 (see FIG. 5) engaged with the main lever 4, and the tape pull-out posts 7a and 7b are between the imaginary line position shown in FIG. 6 and the loading completion position shown by the solid line. Is configured to move.
[0007]
Specifically, the tape pull-out posts 7a and 7b are composed of a post main body 23 and a boat 24 into which the post main body 23 is press-fitted, and an engagement protrusion 24a formed on the boat 24 engages with the chassis 14. The guide grooves 15a and 15b are configured to be movable.
[0008]
An insertion expansion hole 25 wider than the guide groove is formed near the end of the guide groove 15a, 15b near the tape cassette, as shown in FIG. The protrusion 24a is aligned so as to enter the insertion expansion hole 25 of the chassis 14, and the lower part of the boat 24 is inserted into the chassis 14 from the upper surface side of the chassis 14, and the boat 24 inserted into the chassis 14 is indicated by a virtual line in FIG. Thus, the boat 24 is mounted on the chassis 14 by slightly moving toward the loading completion position. In this manner, with the boat 24 mounted on the chassis 14, the leading ends of the loading arms 16 a and 16 b are inserted into the shaft 24 b protruding from the bottom of the boat 24.
[0009]
A light guide 26 is inserted and attached to the chassis 14 from the back surface of the chassis 14, and the tip is inserted into a tape end detection recess formed near the center of the back surface of the tape cassette 27 as shown in FIG. The light emitted from the light emitting diode incident on the base end 26a of the light guide 26 is projected into the tape cassette 27 and contributes to detecting a transparent tape leader portion at the tape end.
[0010]
The tape cassette 27 is a standard product of the VHS video cassette system, and the light guide 26 is also defined in this standard.
[0011]
[Problems to be solved by the invention]
In such a conventional configuration, the engagement protrusion 24a is provided on the boat 24, and the insertion expansion hole 25 is provided in the vicinity of the ends of the guide grooves 15a and 15b, whereby the tape drawing posts 7a and 7b to the chassis 14 are provided. Easy installation.
[0012]
However, the tape pull-out posts 7a and 7b when the tape cassette and the tape cassette are lowered to the loading start position so that the mounted tape pull-out posts 7a and 7b are not caught in the insertion expansion holes 25 and prevent the boat 24 from moving smoothly. It is necessary to position the tape drawer posts 7a and 7b at the standby position so that the tape is accurately inserted into the recess formed in the front surface of the tape cassette.
[0013]
Therefore, conventionally, the loading arms 16a and 16b in the standby position are positioned in contact with the chassis 14 side.
Specifically, in the case of the loading arm 16b, as shown in FIG. 9, the protrusion 28 provided on the chassis 14 side is positioned in contact with the loading arm 16b.
[0014]
However, since positioning is performed via the loading arm 16b in order to position the tape drawing post 7b at the standby position, there is a problem that mechanical backlash occurs and the positioning becomes inaccurate.
[0015]
It is an object of the present invention to provide a magnetic recording / reproducing apparatus having a structure in which a tape pull-out post can be easily mounted on a chassis, the tape pull-out post at the standby position is accurately positioned, and the number of parts is not increased.
[0016]
[Means for Solving the Problems]
The magnetic recording / reproducing apparatus of the present invention is characterized in that the light guide used for detecting the tape end is provided with a positioning protrusion that directly contacts the boat on the drawer post side at the standby position.
[0017]
According to the present invention, it is possible to obtain a magnetic recording / reproducing apparatus having a structure in which the tape drawer post can be easily attached to the chassis, the tape drawer post at the standby position is accurately positioned, and the number of parts is not increased.
[0018]
[Means for Solving the Problems]
The magnetic recording / reproducing apparatus of the present invention is a magnetic recording / reproducing apparatus that drives a boat provided with a drawer post and winds a magnetic tape drawn from a tape cassette around the rotating head cylinder to record / reproduce the magnetic head. A guide groove provided in the chassis, defining a boat movement path, and provided in the boat movement range when the tape is pulled out in the guide groove, and is wider than the guide groove near the end near the tape cassette and the boat. An insertion expansion hole that is movably engaged with the guide groove, and the boat is inserted into the insertion expansion hole when the boat is attached to the chassis, and the boat is attached to the chassis. Has an engaging projection for holding the boat on the chassis and a tip attached to the chassis with a Is inserted into the tape end detection recess formed in tape cassette, and the proximal end the boat standby position is inserted tip end of the tape cassette near the guide groove in a state attached to the chassis the engaging projection in contact with the you characterized by providing a light guide positioning projections are formed for restricting the movement of the boat so as not to engage with the insertion expansion hole.
[0019]
Hereinafter, embodiments of the present invention will be described with reference to FIGS.
In addition, the same code | symbol is attached | subjected and demonstrated to what has the effect | action similar to FIGS. 4-9 which shows a prior art example.
[0020]
As shown in FIG. 2, the light guide 26 used in the magnetic recording / reproducing apparatus of the present invention has a base end portion that engages with the chassis 14 and holds the light guide 26 so that it does not fall off the chassis 14. The joint portion 26b and the positioning projection 26c inserted into the end portion of the guide groove 15b are integrally formed.
[0021]
As shown in FIG. 1, the light guide 26 is inserted into a hole 14 a drilled in the chassis 14 from the back side of the chassis 14, and the engaging portion 26 b is inserted into the chassis 14. It is attached by being engaged with the drilled hole 14b.
[0022]
In this mounted state, the positioning projection 26c of the light guide 26 is inserted into the guide groove 15b, and the boat 24 in the standby state abuts against the positioning projection 26c as shown in FIG. 3, and the boat 24 is the post of the tape drawer post 7b. The main body 23 and the guide roller 29 are positioned at a position where the main body 23 and the guide roller 29 are accurately inserted into a predetermined recess formed on the back surface of the tape cassette 27.
[0023]
Further, in this positioning state, the engagement protrusion 24 a of the boat 24 is positioned at a position where it does not get caught in the insertion expansion hole 25.
Thus, the boat 24 of the tape pull-out post 7b is directly pressed against and abutted against the positioning projection 26c of the light guide 26 on the fixed side without going through the loading arm 16b, and therefore the tape pull-out post 7b and the guide roller 29 The standby position can be more accurately positioned than before.
[0024]
Further, since the positioning projection 26c is formed integrally with the light guide 26, the positioning projection 26c can be positioned at the end of the target guide groove 15b simply by attaching the light guide 26 to the chassis 14 and is easy to assemble. Also, there is no increase in the number of parts.
[0025]
【The invention's effect】
As described above, according to the present invention, the guide groove that defines the moving path of the boat in which the drawer post is planted is provided in the chassis to which the rotary head cylinder is attached, and the vicinity of the end portion of the guide groove near the tape cassette is provided. Is provided with an expansion hole for insertion which is wider than the guide groove and movably engages the boat with the guide groove, and is attached to the chassis and has a tape end formed near the center of the back surface of the tape cassette. The base end of the boat inserted into the detection recess is inserted into the end of the guide groove near the tape cassette so as to abut against the boat at the standby position and not engage with the insertion expansion hole. Because the light guide with positioning protrusions that restrict movement is provided, the light guide positioning protrusions can be attached by attaching the light guide to the chassis. Is inserted into the end of the guide groove, boat waiting position is accurately positioned in direct contact with the light guide of the positioning projections. Further, since the positioning guide is provided on the light guide, the number of parts is not increased.
[Brief description of the drawings]
FIG. 1 is a perspective view of a main part in a standby state on the back surface of a chassis of a magnetic recording / reproducing apparatus of the present invention. FIG. 2 is an enlarged perspective view of a light guide according to the embodiment. FIG. 4 is an explanatory view of the power transmission system of the mechanism of the magnetic recording / reproducing apparatus. FIG. 5 is a plan view of the main part showing the tape loading in progress. FIG. 6 is a rear view of the conventional tape loading completed state. FIG. 8 is a plan view showing the mounting position of the tape cassette of the conventional example. FIG. 9 is a perspective view of the main part in the standby state on the back surface of the chassis of the conventional example. Description】
DESCRIPTION OF SYMBOLS 1 DC motor 3 Main cam gear 7a, 7b Tape drawer post 13 Rotating head cylinder 14 Chassis 15a, 15b Guide groove 23 Post body 24 Boat 24a Engagement protrusion 25 Insertion expansion hole 26 Light guide 26c Positioning protrusion 27 Tape cassette

Claims (1)

In a magnetic recording / reproducing apparatus that drives a boat provided with a drawer post and winds a magnetic tape drawn out of a tape cassette around a rotary head cylinder for recording / reproduction.
A guide groove which is provided in a chassis to which a rotary head cylinder is attached, and which defines a movement path of the boat;
An expansion hole for insertion, which is provided in the boat movement range when the tape is pulled out in the guide groove, and is wider than the guide groove near the end near the tape cassette and movably engages the boat in the guide groove;
An engagement protrusion that is provided in the boat and is inserted into the insertion expansion hole when the boat is attached to the chassis, and holds the boat in the chassis after the boat is attached to the chassis;
Tip mounted on the chassis is inserted into the tape end detection recess formed in the tape cassette, and the proximal end is distal to the end of the tape cassette near the guide groove in a state attached to the chassis A magnetic recording / reproducing apparatus provided with a light guide formed with a positioning projection for restricting the movement of the boat so that the engagement projection does not engage with the insertion expansion hole by contacting the boat in the standby position .

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