JPH09204615A - Magnetic head cleaner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost of a cleaner, and to restrain the number of revolutions to that which does not generate abnormal sound, by rotating the cleaner at two places of a section between a cleaning raw material and a holder and a section between the shaft section of the holder and a bearing section. SOLUTION: A cleaning member 1 is held so as to be freely turned to a bearing 3a integrally formed to a cleaning arm 3 in height, in which the bearing 3a can be abutted against a rotary magnetic head 104, on the outer circumference of a rotating cylinder 105. The cleaning arm 3 is pivoted to a shaft 122 implanted to a plate 123, and a hook section 3b, to which a spring body 125 is hooked, is molded near a shaft section. When a magnetic tape is drawn out, a shaft 205c implanted to a P driving arm 205 following the revolution of a loading motor rotates an arm 15 in the direction A. The arm 15 turns a roller operating arm 124 in the direction B. When the arm 124 is revolved, the cleaning arm 3 is pulled by the spring body 125, and the cleaning member 1 is abutted against the rotating cylinder 105.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device for a magnetic head mounted on a rotary cylinder of a home video tape recorder (hereinafter referred to as VTR).

[0002]

As is well known, when foreign matter or dirt adheres to the surface of a rotary magnetic head, normal magnetic recording or reproduction on a magnetic tape cannot be performed. Particularly in a home-use VTR, the rotary magnetic head is for recording / reproducing image information on / from a magnetic tape, and if foreign matter or dirt adheres to the surface of the rotary magnetic head (especially the magnetic gap part), the magnetic head and the magnetic tape. Spacing loss will occur between them, and normal recording and reproduction of video information will not be performed. Specifically, it will not be possible to project a beautiful video on the TV screen, and this will significantly impair the commercial value. For this reason, the conventional apparatus provides a magnetic head cleaning device in view of this point.

A conventional example will be described with reference to FIG. The cleaning member 1 of the cleaning device has a cylindrical shape, and the cleaning member 1 is pressed against the magnetic head 104 mounted on the cylinder 105 to rotate and clean the magnetic head 104. The cylindrical cleaning member 1 is formed by cutting a material 2 having an excellent dirt removing effect into a circular shape and stacking the cut material into a cylindrical shape. The upper and lower holders 4 and 5 formed of synthetic resin integrally have flange portions 4a and 5a and rotating shafts 4b and 5b, respectively. This structure is used because it has a small number of parts and can be manufactured at the lowest cost.

If the cleaning member 1 does not rotate at all, the dirt removed from the magnetic head will remain, and the cleaning operation will always hit the magnetic head 104. In this case, not only is it possible that the dirt that has been taken is transferred to the magnetic head 104 again, but there is a possibility that the dirt may damage the magnetic head 104. For this reason, the cleaning member 1 is always rotated in order to bring out a new cleaning surface, but its driving force is obtained from the rotating cylinder 105 which has the magnetic head 104 built therein.

Here, the inner diameter of the material 2 and the supporting portion 5c of the holder
The outer diameter of was the press-fitting dimension. This makes it possible to finely adjust the relative speed between the magnetic head 104 and the cleaning member 1 by rotating only one rotating shaft consisting of 4b and 5b, and further, when assembling the cleaning member 1, the upper and lower holders 4 and 5 are attached.
This is to prevent the material 2 from coming off before press-fitting.

The running speed of the magnetic head 104 is 5.8 m / s
Since the diameter of the cleaning member 1 is about 9 mm, when the cleaning member 1 rotates at the same speed as the magnetic head 104, the speed becomes 200 rpm or more. In practice, the magnetic head 10
4 and the cleaning member 1 must have a speed difference, and must be rotated at an appropriate rotational speed for the purpose of always providing a new cleaning surface.

However, due to fluctuation factors such as the coefficient of friction between the surface of the cylinder 105 and the cleaning member 1 depending on environmental conditions, and the diameter of the rotary shafts of the holders 4 and 5 varying depending on the molding conditions, this appropriate rotational speed is obtained. Is difficult to maintain. If it does not rotate, the cleaning effect is lost as described above. Further, even if the cylinder 105 rotates, the cylinder 105 is rotated at a high speed, so that a large number of rotations is likely to occur, and in that case, abnormal noise is generated due to vibration.

In the conventional example, in order to maintain the shaft hole diameter and the shaft diameter with high accuracy, machining was performed after molding, and grease or coating for suppressing vibration was applied. Therefore, the cost for these operations was increased.

As a conventional example, for example, Japanese Unexamined Patent Publication No.
134813 publication etc. are mentioned.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to reduce the cost as a structure having upper and lower holders integrally formed with rotating shafts 4b and 5b, and to suppress the number of rotations at which abnormal noise does not occur. It is to provide a cleaning device that can.

[0011]

In order to achieve the above object, the present invention is configured to rotate at two positions between a cleaning material and a holder and between a shaft portion and a bearing portion of the holder. When rotating at high speed between the shaft portion and the bearing portion, the rotational force is released between the cleaning material and the holder, and rotated between the cleaning material and the holder. That is, a torque limiter mechanism is added in which rotation of the shaft portion and the bearing portion does not rotate more than a predetermined value.

The inner diameter of the cleaning material is slightly larger than the outer diameter of the holder. Since the cleaning material is lightweight and has a small static friction coefficient with respect to synthetic resin, it can be easily rotated by an external force when attached to a support portion slightly larger than the inner diameter of the washer shape.

Since a cleaning material having a smaller rigidity is used, the size for obtaining a predetermined rotational torque may be relatively rough.
Also, when the cleaning material rotates, there is no worry of making an abnormal sound.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a magnetic head cleaning device of the present invention will be described below with reference to the drawings.

The mechanism of a domestic VTR equipped with the magnetic head cleaning device according to the present invention will first be outlined. The household VTR according to the present invention is wound around a reel 108 in a cassette 107 and contains a magnetic tape 106 as shown in FIG. Magnetic tape 106
When a video signal is to be recorded / reproduced on / from the magnetic tape 106, the magnetic tape 106 is pulled out by the tape pull-out body 109 in the direction of the arrow, wound around the rotary cylinder 105, and mounted on the rotary cylinder 105 as shown in FIG. Magnetic recording / reproduction is performed on the magnetic tape 106 by the magnetic head 104.

In this way, the magnetic tape 106 is attached to the cassette 10.
The details of one embodiment of the present invention in the VTR of the type in which the VTR is pulled out from the No. 7 and stored.

The VTR of the present invention employs a so-called full loading function in which the magnetic tape 106 is put on the rotary cylinder 105 in a standby state and FF / Rew is performed. FIG. 5 shows a plan view of the tape loading system of the mechanism. When the inserted cassette 107 reaches the mounting position, the loading motor 110 rotates and the magnetic tape 106 is pulled out. After being further pulled out, as shown in FIG. 4, the tape drawer 109 is pressure-bonded to a predetermined position in the vicinity of the rotary cylinder 105, and the magnetic tape 106 is wound around the rotary cylinder 105. In FIG. 5, a worm gear 111 is integrally connected to the output shaft 110a of the motor 110. A worm wheel 112 that rotates in mesh with the worm gear 111,
A relay gear 201 that meshes with the worm wheel 112, and a cam gear 202 and a cam gear 203 that mesh with the relay gear 201 are rotatably supported on the chassis 100. The cam gear 203 has a cam groove 203a formed on the front surface side, and a pin 205a installed on the rotating arm 205 is fitted in the cam groove 203a. A gear 205b is cut on the other end of the rotary arm 205, and the P drive gear 20
Mesh with 6. The P drive gear 206 further includes the P cam gear 20.
Mesh with 7. A spiral cam groove (not shown) is cut in the P cam gear 207, and the P cam gear 207 is formed by a boss (not shown) of the P cam 208 engaged with the cam groove.
The P-cam 208 moves up and down according to the rotation of the P-cam 208, and the pinch roller 209 mounted on the P-cam 208 descends and rises according to the loading of the magnetic tape 106.

Next, the structure of the head cleaning mechanism will be described with reference to FIG. The cleaning member 1 is rotatably held on the outer circumference of the rotary cylinder 105 by a bearing 3a integrally formed with the cleaning arm 3 at a height at which the rotary magnetic head 104 can be contacted. The cleaning arm 3 is axially supported by a shaft 122 that is planted in a plate 123, and a hook portion 3b for hanging a spring 125 is formed near the shaft portion.

When the magnetic tape 106 is pulled out, the P drive arm 2 is rotated by the rotation of the loading motor 110.
The shaft 205c implanted in 05 rotates the arm 15 in the arrow A direction. Further, the arm 15 rotates the roller operation arm 124 in the arrow B direction. The state after the rotation is shown in FIG. The roller operation arm 124 is the elastic body 1.
25 is hooked on the hook 124a, and when the roller operation arm 124 rotates, the cleaning arm 3 moves the spring 125.
The cleaning member 1 comes into contact with the rotary cylinder 105. Here, the plate 123 is the roller operation arm 1
24 is supported.

A shaft 205c of the roller operation arm 124 is arranged by the P drive arm 205 so as to have a timing to rotate clockwise when the magnetic tape 106 is pulled out, between the FF / Rew mode and the reproduction mode. In the FF / Rew mode, the reproduction mode, the stop mode, and the unload mode, the P drive arm 205
Do not touch. That is, the cleaning member 1 is FF / Rew
The rotary cylinder 105 is contacted only in the middle of the mode and the reproduction mode, and in the middle of the unload mode and the stop mode, and not in the respective modes. Therefore, the tape drawer body 109 remains pressed, and the magnetic tape 106
The cleaning member 1 comes into contact when the sheet is pulled out.

FIG. 1 shows a sectional view of the cleaning member 1. The cleaning member 1 is formed by stacking cylindrical raw materials 2 and forming a hole in the center to pass through the upper and lower holders 4 and 5. The hole diameter at the center is set to be slightly larger than the outer diameters of the upper and lower holders. When the cleaning member 1 comes into contact with the cylinder 105, the holder shafts 4a and 5a and the bearing portion 3a of the cleaning arm 3 are provided.
Rotational resistance is generated between and 3b. When the number of rotations increases and the resistance value also increases and exceeds a predetermined value, the material 2 starts rotating around the upper and lower holders 5 as an axis.

[0022]

According to the present invention, the holder for the cleaning material and the arm on which the cleaning member is placed can be made of synthetic resin, and the bearing part does not require additional work such as machining or coating. Can contribute to cost reduction of parts.

[Brief description of drawings]

FIG. 1 is a sectional view of a cleaning member according to an embodiment of the present invention.

FIG. 2 is a sectional view of a conventional cleaning member.

FIG. 3 is a diagram showing how the magnetic tape is stored in the cassette.

FIG. 4 is a diagram showing a state in which a magnetic tape is pulled out from the cassette.

FIG. 5 is a plan view of the elements of the loading system of this embodiment.

FIG. 6 is a plan view of the vicinity of the cleaning member.

FIG. 7 is a plan view showing a state where the cleaning member is in contact with the cylinder.

[Explanation of symbols]

1 ... Cleaning member, 2 ... Cleaning material, 3 ... Cleaning arm, 4 ... Holder upper flange, 5 ... Holder lower flange, 105 ... Cylinder.

Claims (1)

[Claims] 1. A magnetic recording / reproducing apparatus for pulling out a magnetic tape stored in a cassette and winding the magnetic tape around a rotary cylinder equipped with a magnetic head for recording / reproducing. A cleaning device for cleaning the head by supporting a shaft formed integrally from the upper and lower flanges to be rotatable and abutting against a rotating cylinder containing the magnetic head to clean the head; And an outer diameter of the holding member of the cleaning material is set to a dimensional difference in which the cleaning material receives a rotational force from the rotary cylinder due to the pressing force of the contact and the cleaning material rotates between the holding material and the holding member. Magnetic head cleaning device.