JPH10222898A - Tape tension controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate work for fine adjustment of braking force by fitting a band holder fixed with an end part of a brake band for braking a reel base so as to be turnable with a tension arm and its projecting part as fulcra respectively and turning the band holder around the fulcrum on the arm side as the center. SOLUTION: The metallic tension arm 3 and its projecting part 7 are provided with grooves 13 and 14 respectively, and a chassis 9 fitted freely turnably with the arm 3 is provided with a notch 17 to coincide with the groove 14. A jig 18 having a 1st engagement part to be engaged with the groove 14 and the notch 17 and a 2nd engagement part 20 to be engaged with the groove 13 is used, and by moving circularly arcuately the 2nd engagement part 20 of this jig 18 around the 1st engagement part 19 as the center, the projecting part 7 is bent as against the tension arm 3, and hence the band holder is turned around the fulcrum 16 as the center so that the braking force on the reel base by the brake band is finely adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape tension control device used for a tape recorder, a VTR, and the like.

[0002]

2. Description of the Related Art Conventionally, as a device of this type, a tension arm which is urged by an elastic member and has a portion which comes into contact with a tape, and a brake band which brakes a reel stand on a side where the tape is wound or supplied is provided. And a band holder having one end and the other end of the band fixed together and attached to the tension arm, wherein the tension arm moves against the elasticity of the elastic member according to the tension of the tape. A tape tension control device is known in which the movement controls the braking of the reel base by the brake band, thereby controlling the tension of the wound or supplied tape to be constant.

The tension arm is made of metal, the band holder is made of resin, and a resin-molded press-fit boss is provided integrally with the band holder. The press-fit boss is tightly attached to the hole of the tension arm. By pivotally fitting and attaching the band holder to a tension arm, and finely rotating the band holder with respect to the tension arm, the braking force of the reel base is finely adjusted,
It is also conceivable that variations in the dimensions of the components such as the brake band and variations in the braking force caused by variations in the mounting positions of the components are made uniform, so that the tension of the tape can be controlled in a stable state.

By the way, as described above, the tension arm is formed of metal, and the band holder is formed of resin.
A press-fit boss molded of resin is provided integrally with the band holder, and the press-fit boss is fitted into the hole of the tension arm so as to be rotatably tightly attached, and the band holder is attached to the tension arm. When the holder is slightly rotated, when the band holder is slightly rotated about the press-fit boss, the press-fit change due to a press-fit dimensional defect or shrinkage of the resin due to a change in temperature or humidity may cause the holder to change. It may loosen in the rotation direction.

In order to solve such a drawback, the present applicant has proposed the following tape tension control device. That is, a substantially U-shaped notch is provided in the metal tension arm, and a tip of the convex portion formed by the notch in the tension arm and a portion facing the tip are opposed to each other. Formed grooves,
A press-fit boss of the band holder is fitted to the tension arm at a position other than the above-mentioned convex portion of the arm as described above, and another boss of the band holder is rotatable at the convex portion. And a flathead screwdriver is fitted into both of the grooves to rotate, thereby bending the convex portion with respect to a portion of the tension arm other than the convex portion. The band holder is rotated around the press-fit boss to adjust the braking force of the reel base by the brake band.

[0006]

According to the tape tension control device proposed by the applicant of the present invention, the convex portion of the tension arm is bent with respect to the tension arm by the driver, and the band holder is rotated. Therefore, during the bending operation, the tension arm rotates with respect to the chassis on which the tension arm is rotatably mounted, and there is a problem that the bending operation becomes difficult. In view of the above, the present invention prevents the tension arm from rotating with respect to the chassis during the operation of bending the convex portion, and thereby finely adjusts the braking force of the reel base by the brake band. It is an object of the present invention to provide a tape tension control device that can be easily adjusted.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and achieve the above object, a tape tension control device according to the present invention is provided with a tension arm having a portion urged by an elastic member and brought into contact with the tape. A brake band that brakes the reel stand on the side where the tape is wound or supplied, and a band holder having one end and the other end of the band fixed together and attached to the tension arm, In accordance with the tension of the tape, the tension arm is moved against the elasticity of the elastic member, and the movement controls the braking of the reel base by the brake band, whereby the tape wound or supplied is wound. In a tape tension control device that is controlled so that the tension of the tape is constant,

A substantially U-shaped notch is provided in the metal tension arm, and a tip of a convex portion formed by the notch in the tension arm;
Grooves facing each other are formed in a portion facing the front end, and a notch substantially matching the groove formed in the facing portion is provided in a chassis to which the tension arm is movably attached, The tension arm has the above-mentioned convex portion of the arm, and the band holder is rotatably attached to a portion excluding the convex portion as a fulcrum. A first fitting portion fitted to both of the notches provided in the chassis so as to substantially coincide with each other, and a second fitting fitted to the groove formed in the convex portion By using a jig integrally formed with the mating portion and moving the second fitting portion in an arc shape around the first fitting portion of the jig, the convex portion is The part of the tension arm excluding the convex part is bent. Whereby, the band holder is rotated, and is characterized in that the reel stand of the braking force by the brake band were to be finely adjusted.

[0009]

According to the tape tension control device of the present invention configured as described above, the notch provided in the chassis so as to substantially coincide with the groove formed in the opposed portion and the groove. The first fitting portion of the jig is fitted into both of the jigs, and the second groove is formed in the groove formed in the convex portion.
And the second fitting portion is moved in an arc shape around the first fitting portion of the jig, whereby the convex portion is formed by the convex portion of the tension arm. It is bent to the part excluding the shape part. Thereby, the band holder is rotated, and the braking force of the reel base by the brake band is finely adjusted.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a VTR will be described below with reference to the drawings. FIG. 1 shows the vicinity of the tension arm of the VTR and the reel stand on the supply side, and FIG. 2 is an enlarged view of the portion circled in FIG. FIG. 3 shows a jig. In FIG. 1, reference numeral 1 denotes a brake band, which is wrapped around the braking surface of the reel base 5 in a known manner, and both ends of which are fixed to the band holder 6 by welding, press fitting, hooks, or the like. Reference numeral 3 denotes a metal tension arm, which has a post 11 with which a tape 10 supplied from a reel (not shown) on the reel base 5 side comes into contact. Have been. It is urged by a spring 4 in a counterclockwise direction in the figure.

As shown in FIG. 2, the tension arm 3 is provided with a substantially U-shaped notch 12, and the notch forms a convex portion 7. This convex part 7
A groove 13 and a groove 14 facing each other are formed at a tip of the chassis 9 and a portion facing the tip, and a cutout 17 substantially corresponding to the groove 14 is provided in the chassis 9. The tension arm 3 includes the above-described convex portion 7 of the arm and a portion excluding the convex portion 7 as a fulcrum 1.
The band holders 6 are rotatably mounted as 5 and 16. FIG. 2 shows a state in which the band holder 6 is removed. The hatched portion from the upper right to the lower left indicates the tension arm 3, and the hatched portion from the upper left to the lower right indicates a cutout portion in the chassis 9. .

The convex portion 7 is connected to the tension arm 3
By bending the portion excluding the convex portion 7,
The band holder 6 is rotated about the fulcrum 16, and the braking force of the brake band 1 on the reel base 5 is finely adjusted.

FIG. 3 shows a jig 18 which is provided in both the groove 14 and the notch 17 provided in the chassis 9 so as to substantially coincide with the groove 14. The convex first fitting portion 19 to be fitted and the convex second fitting portion 20 fitted to the groove 13 formed in the convex portion 7 are integrally formed. I have. By using this jig 18 and moving the second fitting part 20 in an arc shape around the first fitting part 19 of the jig 18, the convex part 7 is attached to the tension arm 3. The band holder 6 is rotated about the fulcrum 16 and the braking force of the brake band 1 on the reel base 5 is finely adjusted. During the bending operation, the first fitting portion 19
Is the notch 1 in the groove 14 of the tension arm 3 and the chassis 9
7, the tension arm 3 does not rotate with respect to the chassis 9, thereby facilitating the above operation.

The fulcrum 16 is formed by a press-fit boss integrally formed with the resin band holder 6, and the press-fit boss is press-fitted into a hole formed in the metal tension arm 3 so as to form a band. The holder 6 is attached to the tension arm 3 so as to be able to rotate tightly. The fulcrum 15 is constituted by a boss formed integrally with the band holder 6, and the boss is rotatably fitted in a hole of the tension arm 3.

In the tape tension control device configured as described above, the tension arm 3 is rotated counterclockwise around the press-fit boss serving as the fulcrum 16, whereby
The tension band 1 tightens the braking peripheral surface of the reel base 5, and the rotation of the reel base 5 is controlled by the frictional resistance between the braking peripheral surface and the brake band 1. At this time, the frictional resistance between the brake band 1 and the braking peripheral surface is not uniform due to the variation in the mounting position of the parts and the dimensional accuracy, and the original tape tension cannot be maintained. Therefore, the tightening by the tension band 1 is adjusted. However, if a mechanism for producing a stable tape tension is required, if the band holder 6 is attached to the tension arm 3 only by the press-fit boss serving as the fulcrum 16 as this mechanism, the tension arm 3 rotates as described above. When the tension brake is applied, a force acts in a direction in which the band holder 6 is returned by the brake band 1. For this reason, in order to secure a constant braking force, the press-fit of the press-fit boss of the band holder 6 must be a press-fit that can withstand it.

In this respect, in FIG. 1 described above, a small boss protruding from the bottom surface of a portion serving as the fulcrum 15 of the band holder 6 is fitted into the hole of the convex portion 7 of the tension arm 3,
In order to adjust the braking force by the brake band 1, when the band holder 6 is rotated, the jig 18 is inserted into the grooves 13, 14 and the notch 17 as indicated by reference numeral 8 and rotated, thereby forming a convex shape. The part 7 bends upward or downward in the drawing, and the fulcrum 15 becomes the point of action, and the band holder 6 rotates about the fulcrum 16. Since the rotation of the band holder 6 is accompanied by the bending of the convex portion 7 in this manner, the fine adjustment of the braking force by the brake band 1 can be easily realized by the slight rotation of the band holder 6 and the tension arm 3 In this case, the band holder 6 can be repeatedly adjusted without loosening, and high reliability can be obtained with respect to dimensional defects of the press-fit bosses constituting the fulcrum 16 and variations in press-fit due to shrinkage of the resin due to temperature and humidity changes. Can be.

In the above-described embodiment, the brake on the supply-side reel base is described. However, the reel-side reel base on the take-up side can be implemented in substantially the same manner.

[0018]

As described above, the tape tension control device of the present invention comprises a tension arm 3 having a portion such as a post 11 which is urged by an elastic member such as a spring 4 and is brought into contact with a tape 10; A brake band 1 for braking the reel base 5 on the side where the tape 10 is wound or supplied; and a band holder 6 having one end and the other end of the brake band 1 fixed together and attached to the tension arm 3 The tension arm 3 is moved, such as rotating, against the elasticity of the elastic member in accordance with the tension of the tape 10, and this movement causes the brake band 1 to brake the reel base 5. A tape tension control device that is controlled so that the tension of the wound or supplied tape 10 is controlled to be constant. In,

A substantially U-shaped notch 12 is provided in the metal tension arm 3, and the tip of the convex portion 7 formed by the notch 12 in the tension arm 3 faces the tip. Grooves 13 and 14 facing each other are formed in a portion where the tension arm 3 is movably mounted, and a notch 17 substantially corresponding to the groove 14 formed in the above-described facing portion is formed in the chassis 9 to which the tension arm 3 is movably attached. Is provided on the tension arm 3.
The band holder 6 is rotatably attached to the above-mentioned convex portion 7 with the portions excluding the convex portion 7 as fulcrums 15 and 16, and the groove 14 and the groove 14 formed in the above-mentioned opposing portions are formed. The first fitting portion 19 fitted to both the notch 17 provided in the chassis 9 so as to substantially match with the first fitting portion 19 and the groove 13 formed in the convex portion 7 Jig 18 integrally formed with second fitting portion 20 to be formed
By moving the second fitting portion 20 in an arc shape around the first fitting portion 19 of the jig 18,
The convex portion 7 is bent with respect to a portion of the tension arm 3 excluding the convex portion 7, whereby the fulcrum 16
Since the band holder 6 is rotated around the center to finely adjust the braking force of the reel base 5 by the brake band 1,

Compared with the case where the fulcrum 15 is not provided, a higher reliability is obtained in the loosening torque of the brake holder 6 with respect to the tension arm 3 due to a change or variation in the press-in force due to a press-fit dimensional defect or a resin shrinkage due to a temperature change. Obtained
In addition, the work at the time of adjustment can be easily performed, and by using the jig 18, the second fitting portion 20 of the jig 18 is moved in an arc around the first fitting portion 19, The convex portion 7 is bent with respect to a portion of the tension arm 3 other than the convex portion 7, whereby the band holder 6 is rotated around the fulcrum 16, and the reel is moved by the brake band 1. By finely adjusting the braking force of the platform 5, the first fitting portion 19 can be used during the bending operation described above.
Is the notch 1 in the groove 14 of the tension arm 3 and the chassis 9
7, the tension arm 3 does not rotate with respect to the chassis 9, thereby facilitating the above operation.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is an enlarged plan view of a main part of FIG.

FIG. 3 is a perspective view showing the adjustment jig of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Brake band 2 axis 3 Tension arm 4 Spring 5 Reel base 6 Band holder 7 Convex part 9 Chassis 10 Tape 11 Post 12 Notch section 13, 14 groove 15, 16 Support point 17 Notch 18 Jig 19 First fitting Part 20 Second fitting part

Claims (1)

[Claims] 1. A tension arm urged by an elastic member and having a portion that comes into contact with a tape, a brake band that brakes a reel stand on a side where the tape is wound or supplied, and one end of the band. A band holder fixed to the other end thereof and attached to the tension arm, wherein the tension arm is moved against the elasticity of the elastic member according to the tension of the tape, and the movement of the brake band In the tape tension control device, the braking of the reel base is controlled by the above, so that the tension of the wound or supplied tape is controlled to be constant. A notch having a convex shape formed by the notch in the tension arm. A groove facing each other is formed in a portion facing the front end and a portion facing the front end, and a cutout substantially matching the groove formed in the facing portion is formed in a chassis to which the tension arm is movably attached. The notch is provided, and the band holder is rotatably mounted on the tension arm with the convex portion of the arm and a portion excluding the convex portion as a fulcrum, and the groove formed in the opposed portion. And a first fitting portion fitted into both the notch provided in the chassis so as to substantially match the groove, and fitted into the groove formed in the convex portion By using a jig integrally formed with the second fitting portion and moving the second fitting portion of the jig in an arc shape around the first fitting portion,
The convex portion is bent with respect to a portion of the tension arm other than the convex portion, whereby the band holder is rotated, and the braking force of the reel base by the brake band is adjusted. A tape tension control device.