JPH03134812A - Cleaning member elevating/lowering mechanism for magnetic recording and reproducing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cleaning device for a magnetic head mounted on a rotating cylinder of a home video tape recorder (hereinafter referred to as VTR).

[Conventional technology]

A conventional device includes a cleaning brush for cleaning a rotating magnetic head as described in Japanese Patent Application Laid-Open No. 1-191317, in which the rotating axis of the cleaning brush is tilted in the circumferential direction with respect to the rotating axis of a rotating cylinder. There are some products designed to improve cleaning effectiveness.

As is well known, when foreign matter or dirt adheres to the surface of a rotating magnetic head, normal magnetic recording and reproduction on a magnetic tape cannot be performed. Particularly in home VTRs, rotating magnetic heads record video information on magnetic tape.

The surface of the rotating magnetic head (
If foreign matter or dirt adheres to the magnetic gap (particularly the magnetic gap), it will cause a spacing loss between the magnetic head and the magnetic tape, preventing normal recording and playback of video information, and specifically preventing beautiful images from being displayed on the TV screen. This results in a significant loss in product value. Therefore, the conventional device provides a magnetic head cleaning device in view of this point.

[Problem to be solved by the invention]

The above conventional technology simply tilts the rotation axis of the cleaning brush (cleaning member), and the contact point between the magnetic head and the cleaning member is always the same, so the cleaning member gets dirty in a short time, and the so-called This was insufficient in terms of extending the life of the cleaning member. Furthermore, there is room for improvement in streamlining and lowering the cost of the entire cleaning device. In other words, the above-mentioned conventional technology uses a plunger to operate the cleaning member, and as is well known, if an electromagnetic component such as a plunger is used, a drive electric circuit etc. will also be required, resulting in a considerable increase in cost. It was unsuitable for application to home VTRs and the like.

SUMMARY OF THE INVENTION An object of the present invention is to provide a mechanism that can provide reliable operation with a simple structure in which the contact point between the magnetic head and the cleaning member is sequentially changed each time the cleaning member is pressed onto the magnetic head.

[Means to solve the problem]

In order to achieve the above object, the present invention utilizes the movement of a member that pulls out a magnetic tape stored in a cassette and winds it around a rotating cylinder, and stores the magnetic tape in the cassette. The cleaning member has a cylindrical cam member and a cylindrical shape. The coil-shaped member was used as a one-way clutch mechanism to prevent reverse rotation, and realizations 1 to 1 were achieved.

[Function] The cleaning member 7 is designed to press against the rotating magnetic head in conjunction with the operation of pulling out and storing the magnetic tape in the cassette, and when the pulling operation and storage operation are completed, the cleaning member is cleaned from the magnetic head. Since the members are separated from each other, the pressing operation time of the cleaning member is approximately 1 to 2 seconds, and there is no risk of damage to the magnetic head.

In addition, the cylindrical cam member is rotated by a certain angle by using the movement of the member that performs the crimping operation of the cleaning member, and the cylindrical cam member does not reverse rotation due to the action of the reversal prevention mechanism of the cylindrical coiled member. Each time there is a drawer or storage operation,
It is possible to rotate a fixed angle cam roller in only one direction. This allows the height of the cleaning member to be changed by the action of the cam roller.

The cleaning member's crimping, separating, and height changing operations are performed in conjunction with the magnetic tape pull-out and storage operations, so there is no fear of timing shifts between the two operations, resulting in stable operation. It is possible to obtain a mechanism that

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
6 to 6 show an embodiment of the present invention. FIG. 1 is a side view of the main part in operation, FIG. 2 is an exploded perspective view of the main part, FIG. 3 is a plan view of the main part in operation, and FIG. 5 is a sectional view of the cleaning member, FIG. 5 is a plan view of the operating state, FIG. 6 is a plan view of the non-operating state, and FIG.
The figure shows a state in which the magnetic tape is housed in the cassette, and FIG. 8 shows a state in which the magnetic tape is pulled out of the cassette. FIG. 9 is a plan view of the tape drawer in a non-operating state;
FIG. 10 is a plan view of the tape drawer in an operating state.

First, the mechanism of the home VTR equipped with the head cleaning device according to the present invention will be explained. As shown in FIG. 7, the household VTR according to the present invention has a magnetic tape 10 wound around a reel 108 in a cassette 107.
6 is stored. Here, when trying to record and reproduce a video signal on the magnetic tape 106, as shown in FIG.
The magnetic tape 106 is pulled out by the tape drawer 109 in the direction of the arrow.
is pulled out and wound around a rotating cylinder 105, and a rotating magnetic head 104 mounted on the rotating cylinder 105 performs magnetic recording and reproduction on a magnetic tube 106 (this is a well-known technique).

The details of one embodiment of the present invention in a VTR in which the magnetic tape 106 is extended from the cassette 107 and stored in this manner will be described in detail below. First, the configuration will be explained, and then the operation will be explained. In FIGS. 9 and 10.

A worm gear 111 is attached to the output shaft 110α of the motor 110.
are integrally combined. A worm wheel 112 that engages and rotates with a worm gear 111, and a cam gear 116 that engages and rotates with the worm wheel 112 are rotatably supported on the chassis 100. The cam gear 116 has a cam groove 116a carved on the back side, and the pin 103α installed on the pull-out arm 106 with the rotation axis of the worm wheel 1120 as the rotation axis is inserted into the cam groove 116a.
It is fitted in.

The pull-out arm 103 has a rotation shaft hole 105c at one end, a rack engagement hole 1034 at the other end, and an arcuate portion 103b at its tip. chassis 10
0, a rack plate 11 is attached to the rack plate 11 so as to be slidable in the longitudinal direction.
4 is provided with a rack gear 114α on one end side and a rack boss 114b on the other end side, and the rack boss 114b is inserted into the rack engagement hole 103d of the drawer arm 106. The route is in a movable mounted state, and the drive gear 115.
The rotation of 116 causes the first arm 117°119 and the second
It is configured to be movable a predetermined distance via arms 118, 120. The above is the configuration for pulling out and storing the magnetic tape 106 from the cassette 107.

Next, the configuration of the head cleaning mechanism is shown in Figures 1 and 2.
This will be explained using FIGS. 3, 4, 5, and 6. The structure of the cleaning member 1 (Fig. 4) is that the cleaning member 1 is connected to the shaft body 1a.
The cap body 1h is press-fitted onto the shaft body 1a from above. At the bottom of this shaft body 1α is a flange portion 1.
It has c.

The cleaning member 1 is rotatably disposed on a shaft 3α erected on the cleaning arm 3 at a height such that it can come into contact with the rotary magnetic head 104 on the outer periphery of the rotary cylinder 105. That is, the cleaning arm 6 is provided with the aforementioned shaft 3α on the tip side,
A rotation shaft hole 6c is provided on the other end, and a shift lever is provided in the middle.
A hole 6b is provided. Shift lever of this cleaning arm
The shift lever shaft 2h of the shift lever 2 is fitted into the hole 3hK, and the shift lever 2 is rotatably supported with respect to the cleaning arm 3. In this state, the operating portion 2α provided at the tip of the shift lever 2 is inserted between the flange portions 1c of the cleaning member 1.

Further (FIG. 1), a spring body 9 is provided between the shift lever 2 and the cleaning arm 30, and is configured to bias the cleaning member 1 upward. Further, a cam contact portion 2c is provided at the end of the shift lever 2 opposite to the operating portion 2α. The cleaning arm 6 in which the cleaning member 1 and the shift lever 2 are installed in this way is inserted into the pivot shaft hole 3c (after the drive lever 6 is assembled into the support 101) through the support 101 installed upright on the chassis 100. Incorporate. A cam roller 4 is disposed at a position where it can come into contact with the cam contact part 2c of the shift lever 2 incorporated in the cleaning arm 3 (in this embodiment, a position below the cam contact part 2c), and the cam roller 4 is attached to the chassis 100. It is incorporated together with the one-way clutch coil member 7 into a roller shaft 102 that is installed upright.

The upper end surface portion of the cam roller 4 forms an end surface cam portion 4α, and the lower portion thereof forms a serrated portion 4b. Further, the one-way clutch coil member 7 is attached to the seat portion 10 of the roller shaft 102.
2a, and the shaft cylinder portion 4c formed on the cam roller 4, straddling and incorporated therein.

Here, the one-way clutch coil member 7 is formed into a cylindrical shape by spirally winding a spring stainless steel wire or the like while maintaining the inner diameter.

Seat 1 with respect to the inner diameter of this one-way clutch coil member 7
02α and the outer diameter of the shaft cylindrical portion 4c are set slightly larger, and by making the helical winding direction of the one-way clutch coil member 7 clockwise, the cam roller 4 is rotated in the direction of the R arrow (in FIG. 3). A so-called one-way rotation mechanism is obtained in which rotation is possible in the clockwise direction (clockwise rotation), but rotation in the counterclockwise direction is prevented (i.e., a one-way clutch mechanism using a well-known coiled spring) is obtained. Form).

Further, the support column 10 is installed upright on the chassis 100 described above.
1, a drive lever 6 which also rotates around the support column 101 is installed on the lower side of the cleaning arm 3 by inserting a rotation shaft hole 6c into the support column 101.

Here, the configuration of the drive lever B is as follows.

A cam portion 6a is formed below the middle of the drive lever B, and a circular arc portion 103 formed at the tip of the pull-out arm 103.
It is operated at b.゛Also, there is a boss 6h on the upper surface of the middle part,
A locking pawl 6g and a hook portion 6d are provided.

Inverted ratchet 7) Lever 5 has J'15a on one end.
, an elastic arm portion 5h integrally formed for biasing the ratchet lever 50 is provided on the other end side, and a shaft hole 5c is provided in the middle portion, and is inserted into the boss 6h of the drive lever B.
The ratchet lever 5 is mounted on the drive lever 6 so as to be rotatable within a predetermined range.
(Figure), it is installed with a clockwise rotational force applied to it.

In addition, the hook part 6 is provided on the side surface of the middle part of the drive lever B.
A spring body 11 is suspended between f and the chassis 100,
A clockwise rotational force is applied to the drive lever 6. The drive lever 6, which is rotatably attached to the support column 101, further has a protrusion 6! near the rotation shaft 6c. Similarly, when the cleaning arm 3 is rotatably mounted on the support 101 and mounted on the drive lever O, the locking portion 6d is configured to abut against the protrusion 61, so that the cleaning arm 3 A to prevent the drive lever from rotating counterclockwise relative to the drive lever. Hook part 6d and 'lk of this drive lever O
A spring body 10 is attached to the tip of the locking part 6d of the cleaning arm O, and the drive lever O has a clockwise rotating force and a cleaning arm 3.
is applied with a counterclockwise rotational force (spring body 1
0) are connected via a strut 10.

The operation of one embodiment of the present invention in the above configuration will be described next.

As mentioned above, the cassette 107 also pulls out and stores the magnetic tape 106 by rotating the motor 110 (9th
10), the worm gear 110, the worm wheel 112, and the cam gear 116 are rotationally driven, and the cam groove 113a of the cam gear 115 is also rotationally displaced. As a result, the pull-out arm 103 rotates in the direction of the arrow (clockwise rotation) in FIG. 10, and pulls up the rack plate 114 in the direction of the arrow.
116 is rotationally driven, and the first arms 117, 119
, the tape drawer 1 via the second arms 118, 120.
09 moves, pulls out the magnetic tape 106, wraps it around the rotating cylinder 105, and performs predetermined magnetic recording and reproduction by the rotating magnetic head 104. Further, when storing the magnetic tape 106 into the cassette 107, the above-mentioned operation is reversed. In order to always perform normal magnetic recording and reproduction, as described above, there must be no dirt or foreign matter adhering to the surface of the rotating magnetic head 1040, especially near the magnetic gap.

The operation of the present invention, which uses the power of the pull-out arm 103 that operates when pulling out and storing the magnetic tape 106 to operate the head cleaning device and always perform normal magnetic recording and reproduction, will be explained below. . FIG. 6 shows the device according to the invention in a non-operating state. FIG. 5 shows the operating state of a similar device. Furthermore, FIG. 3 explains this FIG. 5 in detail.

2. The pull-out arm 103, which operates to pull out and store the magnetic tape 106, is displaced from Pl to positions P2 and P3 (in FIGS. 5 and 6). Pl is the magnetic tape 10 (
When storing 1+, P3 is when the magnetic tape 106 is being pulled out, and P2 is when the magnetic tape 106 is being pulled out or being stored. Normally, when the device is in a non-operating state as shown in Figure 6,
The drive lever 6 is biased to rotate clockwise by the spring body 11 and is locked at the end face of the chassis 100 in the direction of the arrow. In this state, the locking portion 3d of the cleaning arm 6 is locked to the protrusion 61 of the drive lever 6 by the spring body 10, and the cleaning roller 1 placed on the cleaning arm 3 is locked.
is also spaced apart from the rotating cylinder.

Next, the effects of the operating state of the device shown in FIGS. 6 and 5 will be explained. While the magnetic tape 106 is being pulled out and stored, the pull-out arm 106 is located near P2. At this time, the circular arc portion 103b at the tip of the pull-out arm 103 comes into contact with the cam portion 6α of the drive leno (-6), and as a result, the drive leno (-6) moves counterclockwise (in the direction of the arrow) at a predetermined angle.
The spring body 110 is forced to rotate against the force.

This action also causes the cleaning arm 6 to rotate in the same way.
By configuring the cleaning member to come into contact with the rotating cylinder 105 during this rotational movement, the protrusion 6!1 of the drive lever O and the locking portion 3d of the cleaning arm 3 will separate. As a result, a biasing force for counterclockwise rotation by the spring body 10 is applied to the cleaning arm 6 and the cleaning member 1. That is, by appropriately setting the load of the single strip body 10, the cleaning member 10 rotation cylinder 105
Appropriate pressing force can be obtained. Also, as a matter of course, at least while the cleaning member 1 is being pressed against the rotating cylinder 105, the rotating cylinder is driven to rotate (the rotational driving means for the rotating cylinder is omitted), so that the cleaning member 1 is mounted on the rotating cylinder 105. The rotating magnetic head 104 can be cleaned. Further, a ratchet lever 5 is mounted on the drive lever 6 (FIG. 6), and when the drive lever 6 moves in the direction of the arrow, the pawl portion 5α of the ratchet lever 5 engages the serrated portion 4 of the cam roller 4.
h and rotates the cam roller 4 at a predetermined rotation angle in a clockwise direction (R
It is designed to rotate in the direction of the arrow). The cam roller 4 is assembled to the lower part of the one-way clutch coil member 7.
Because of the zero action, it does not rotate counterclockwise, so each time the drive lever B is operated, it rotates in the direction of the arrow R by a predetermined rotation angle.

As a result, as shown in FIG.
The cam contact portion 2c of the shift lever 2 rotates up and down, and as a result, the flange portion 1c of the cleaning member 1 is operated by the operation portion 2α of the shift lever 2, so that the cleaning member 1 is moved every time the drive lever B is operated. , which performs the action of sequentially changing the position in the height direction.

This makes it possible to change the height position of the cleaning member 1 that contacts (suppresses) the rotating magnetic head 104, so that the same location is not overworked and the life of the cleaning member 1 can be extended. It becomes possible.

To add an explanation, it is important to use the optimum material for the cleaning member 1, including soft materials, cloth materials, paper materials, etc. that will not damage the rotating magnetic head 104. Needless to say, there is.

〔Effect of the invention〕

Since the present invention is configured as described above, it produces the effects described below.

By using the power associated with the operation of pulling out and storing the magnetic tape 106 in the cassette 107, it is possible to contact the rotating magnetic head 104 without installing a special power source (for example, a plunger, a motor, etc.). (Suppression) It is possible to obtain a cleaning device for the rotating magnetic head 104 in which the height of the cleaning member is successively changed to extend the life of the cleaning member.

[Brief explanation of the drawing]

Figure 1 is a side view of the main parts of an embodiment of the present invention in operation;
6 is a plan view of the manufacturing operation of an embodiment of the present invention. FIG. 4 is a sectional view of a cleaning member of an embodiment of the present invention. 5 is a plan view of an embodiment of the present invention in an operating state, FIG. 6 is a plan view of an embodiment of the present invention in a non-operating state, FIG. 7 is a diagram of a state in which a magnetic tape is stored in a cassette, and FIG. FIG. 9 is a plan view of the tape drawer in a valve operating state, and FIG. 10 is a plan view of the tape drawer in an operating state. 1...Cleaning member 2...
・・・・・・・・・・・・Shift lever-3・・・・・・・・・
・・・・・・・・・Cleaning arm 4・・・・・・・・・・・・
・・・Cam roller 5・・・・・・・・・・・・・・・
Ratchetre, <-6・・・・・・・・・・・・・・・
Drive lever 7...One-way clutch coil member 106...Pull-out arm

Claims (1)

[Claims] 1. In a magnetic recording and reproducing device configured to pull out a magnetic tape stored in a cassette and wrap it around a rotating cylinder equipped with a magnetic head, pulling out the magnetic tape,
Alternatively, in an apparatus equipped with a cleaning member that cleans the magnetic head by contacting the magnetic head in conjunction with a member that performs a storage operation, the cleaning member is sequentially removed in conjunction with a magnetic tape pull-out operation or a tape storage operation. The structure is such that the height relative to the magnetic head is changed, and the height changing means includes a cylindrical cam member, one end of which is in contact with the cam surface of the cylindrical cam member,
The other end of the cleaning member is slidably engaged with a member that holds the cleaning member, and a lever having a pivot shaft is provided in the middle part, and the cylindrical cam member is formed into a cylindrical shape as a mechanism for preventing reverse rotation of the cylindrical cam member. A cylindrical cam member is configured to rotate only in one direction by a predetermined rotation angle each time a magnetic tape is pulled out or stored using a wound elastic coil member, and the cam surface of the cylindrical cam member is A cleaning member elevating mechanism for a magnetic recording/reproducing device, characterized in that the height of the cleaning member is changed by transmitting displacement to the cleaning member using the lever.