JPS6364657A - Tape tension controller - Google Patents

Abstract

PURPOSE:To smoothly give tension by providing a brake shoe and a means which presses and energizes a tension detection arm toward the brake shoe outside the tension detection arm and applying brakes on the both sides of a tape. CONSTITUTION:The tape 7 from a supply reel supported on a supply reel stand has a tension T1 due to the load of the reel stand. Said tension is supplied to a recording and reproducing part at a tension T2 through a tension detection member 10, a pressing member 11 and a tape guide roller 12, and halfway the pressing member 11 press-contacts the brake shoe 14 to apply a brake. Since the pressing force F of a spring 13 to the pressing member 11 acts in the direction in which the pressing force of the tape tension T1 decreases, force applied to the brake shoe 14 becomes a force P smaller than a force F. The winding diameter of the tape wound on a supply reel decreases as the tape is used. Consequently the tension T1 decreases to act as suppressing so that the tension T2 can be minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a tape tension control device used in a tape-like material supplying and winding device such as a tape recorder.

2. Description of the Related Art In recent years, tape tension control devices have been widely used not only in audio tape recorders but also in video recorders for stable tape running, stable head touch, tape protection, etc.

Hereinafter, referring to the drawings, it is a diagram illustrating a top view of the main parts of the above-mentioned conventional Qi control device. In the figure, 1 is a tape tension sensor detection arm, 2 is a pivot shaft of the tape tension detection arm 1, and 3 is an indentation element whose outer peripheral surface is wrapped with a material having a high coefficient of friction. It is attached to the tip of 1. 4 is a spring that biases the tape tension detection arm 1 clockwise; 5 is a stator;
6 is a friction body having a high friction coefficient that is wound around the outer periphery of the stator 5, and 7 is a tape.

The operation of the tape tension control device configured as described above will be explained below.

The tape 7 travels in the direction of the arrow, is sandwiched between the stator S and the pressure contact 3, and is pressed by the spring 4. A frictional force is generated between the tapes 7 and 7, which enters the tape with a tension of T1 and reaches the desired tension of T2. The increased amount of data is supplied to the recording/reproducing section. If T1 increases for some reason, the resultant force of T1 and T2 or the spring 40 force acts in a direction that cancels out the increase in T2.

Problems to be Solved by the Invention However, with the above configuration, with respect to changes in T1,
In order to obtain a nearly constant T2, a material with a very large coefficient of friction is required for the friction part, and when such a material is used, there is a problem in that the tape cannot run smoothly. .

In view of the above-mentioned problems, the present invention provides a tape tension control device that can be realized with a friction coefficient that can be easily obtained using a material that has been commonly used in tape recorders, etc., and is durable and provides smooth friction. This is what we provide.

Means for Solving the Problems In order to solve the above problems, the control device of the present invention includes a tension detection arm rotatably supported on a shaft, a pressure contact member provided on the tension detection member, and a pressure contact member provided on the tension detection member arm. Similarly, on the tension detection arm, the tape is placed farther from the shaft support position than the pressure contact member, and the tape is wound around the tension detection member that guides the travel, and the brake that is located outside the tension detection arm and the pressure contact member covers the tape on three sides. The brake shoe includes a shoe and a biasing means for pressing and biasing the tension detection arm toward the brake shoe.

Operation According to the present invention, with the above-described configuration, fluctuations in tape tension detected by the tension detection member are magnified, and the necessary coefficient of friction acting on the pressure contact member can be lowered.

Embodiment Hereinafter, a tape tension control device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a top view of a tape tension control device according to a first embodiment of the present invention. In Figure 1,
8 is a tension detection arm, 9 is a rotation center of the tension detection arm 8, 10 is a tension detection member rotatable at the tip of the tension detection arm 8, 11 is a pressure contact member and is a rotation center 9 of the tension detection arm 8. They are each provided non-rotatably near each other. A tape guide roller 12 is rotatably supported on the rotation center of the tension detection arm 8. Reference numeral 13 denotes a spring that urges the tension detection arm 8 in a clockwise direction, and 14 a brake shoe, which is provided outside the tension detection arm 8 and presses the tape with the pressure contact member 11.

The operation of the tape tension control device configured as described above will be explained below with reference to FIG. - The tape 7 supplied from a supply reel supported on a supply reel stand (not shown) has a tension of T1 due to the load on the reel stand or the load in the cassette. This is connected to the tension detection member 10 as shown in the figure. Pressing member 11.
The tape is supplied through the tape guide roller 12 to the recording/reproducing section at a tension of 2. On the way, the pressure contact member 11 presses the end of the tape against the brake shoe 14, applying a braking force due to frictional force to the tape. F in the figure is the pressure contact force of the pressure contact member 11 by the spring 13, but since the tape tension T1 acts in a direction to reduce the pressure contact force, the force that presses against the brake shoe 14 is a force P smaller than F. The winding diameter of the tape wound on the supply reel decreases as the tape is used, so T1 increases, but the increased tension reduces the pressing force and the braking force applied to the tape 7 decreases, T2
work to suppress the increase in

If a is the distance from the rotation center 9 to the pressure contact part by the pressure contact member 11, and b is the distance from the rotation center 9 to the tip of the tension detection member 1o, then T = T + P (μ 10μ
) ・・・・・・・・・(1) p=p −T
, --------(2) However, μm is the friction coefficient between the tape and the brake shoe, and μ2 is the friction coefficient between the tape and the pressing member (1) + (2) From the equation, T = ( 1-T2 (μ10μ) T +F (μ10μ)...
・(3)2 a121 12, and when there are two (μm+μ2), T2=F(μ, 10μ
2), and it can be seen that even if T1 changes, T2 remains constant.

Now μm=μ2. If odor = 2, then μm = μ2 =: 0.25, and tape and felt,
The coefficient of friction is close to that obtained with conventionally commonly used materials such as tape and stainless steel.

Note that since the mutual values can be arbitrarily determined by design, the degree of freedom in design is extremely limited.

As described above, according to the present embodiment, the tension detection arm is rotatably supported on the shaft, the pressure contact member is fixedly provided on the tension detection arm, and the pressure contact member is also placed on the tension detection arm and is supported on the shaft more than the pressure contact member. There is a tension detection member installed far away from the tension detection arm that guides the tape when it is wound, a brake shoe that is located outside the tension detection arm and which presses the tape, and a pressure detection arm that presses the tension detection arm toward the brake shoe. A tape tension control device with excellent control characteristics can be realized without using any special friction material by applying a brake on both sides of the tape and setting the biasing means to be approximately 2 times each other.

A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a top view of a tape tension control device showing a second embodiment of the present invention. The difference from the configuration shown in FIG. 1 is that a rotatably supported roller is used as the pressure contact.

With this configuration, the frictional sliding surface of the tape can be reduced to only one surface, so it can be used especially when it is desired to avoid sliding on the magnetic surface side of the tape. However, in this case, there is only one braking surface on the tape, so
Either use a material with a large coefficient of friction, or increase -. That is, as in the case of Fig. 1, to realize μ=o, 2s, -24
You can do it as

FIGS. 3 and 4 show the third embodiment of the present invention. FIG. 3 is a diagram showing a fourth embodiment, and FIG. 3 is an example in which the tape tension T2 on the output side is also utilized in FIG. be.

FIG. 4 is a diagram in which the running direction of the tape is reversed in FIG. 3, that is, the inlet side and the outlet side are reversed.

FIG. 6 is a top view showing a fifth embodiment of the present invention, which is applied to a rotary head type recording/reproducing device.

In the figure, 16 is a tape loading block, 1
Reference numeral 6 indicates an inclined guide pin, and reference numeral 1 indicates a slot provided on the chassis for guiding the movement of the tape loading proc 15 during tape loading and unloading operations. 18 is a tape guide roller, 19 is a rotation center of the tension detection arm 8, and 20 is a tape guide roller, which is supported on the tape loading block 15 coaxially with the tension detection arm 8. Note that the spring that biases the tension detection arm can be constructed of a torsion coil spring or the like, and is not shown in FIGS. 5 and 6.

With the above configuration, since the tape tension control device is provided on the tape loading block, the device can be configured compactly, and the tape tension can be added just before the cylinder device (not shown) having a rotating head. Since it can be controlled, the load when driving the tape is smaller compared to the conventional tape tension control system that uses a supply reel stand.It is suitable for downsizing equipment, and also protects the tape and extends its life. The above is also preferred.

Fig. 6 shows a sixth embodiment of the present invention, in which only the pressure contact member is provided on the tape loading block, the tension detection arm is provided on the chassis, and the brake shoe is provided on the tension detection arm. It is.

As mentioned above, the mounting position relationship between the pressure contact member and the brake shoe can be changed arbitrarily, and the support position of the tension detection arm can also be provided not only on the chassis but also on a movable member such as a tape loading block. Therefore, it is possible to realize a tape tension control device that can be used in an extremely wide range of applications.

Although not all of the embodiments can make the calculated T2 a constant value, it is possible to bring it close to a constant value by selecting the friction material and -. In addition, when the tape acts on the tensile run detection member after brake control, or when the tape is wrapped around a fixed pressure member or tensile run detecting member, etc., the control characteristics tend to deteriorate slightly, but in practice As long as T2 is within a certain tolerance range, it can be used without any problem.

In addition, in the embodiment, both the tape on the inlet side and the tape on the outlet side are made to be approximately perpendicular to the rotation radius of the tension detection arm, but this is to make effective use of the tape tension. This is not limited.

Effects of the Invention As described above, the present invention includes a rotatably supported tension detection arm, a pressure contact member provided on the tension detection arm, and a pressure contact member υ provided on the tension detection arm from the pivot position. A tension detection member installed at a distance that guides the movement of the tape, and a brake shoe located outside the tension detection arm that presses the tape with a pressure contact member.
By providing an energizing means that presses the tension detection arm toward the brake shoe, the friction can be easily obtained with conventionally used materials without using a special compound with a high friction coefficient. Durability also depends on the coefficient υ,
A smooth tape tension control device can be realized.

[Brief explanation of the drawing]

FIG. 1 is a top view of a tape tension control device according to a first embodiment of the present invention, FIG. 2 is a top view of the second embodiment, and FIG. 3 is a top view of a third embodiment of the invention. 4 is a top view of the fourth embodiment, and FIG. 5 is a top view of the fifth embodiment showing the present invention implemented on a tape loading block.
FIG. 6 is a top view of a sixth embodiment of the present invention in which the positional relationship of the components in FIG. 5 is changed, and FIG. 7 is a top view of a conventional tape tension control device. 1.8...Tension detection arm, 2,9...
... Rotation center, 3 ... Pressure contact, 5 ...
...Stator, 7...Tape, 10...
Tensilon detection member, 11, old... pressure contact member, 14...
...Brake shoe, 15...Tape loading block.

Claims (9)

[Claims] (1) Wrap around a rotatably supported tension detection arm, a pressure contact member provided on the tension detection arm, and a tape provided further from the support position than the pressure contact member on the tension detection arm. It is characterized by comprising a tension detection member that guides travel, a brake shoe that is located outside the tension detection arm and in which the pressure contact member presses the tape, and an energizing means that presses and energizes the tension detection arm toward the brake shoe. Tape tension control device. (2) The tape tension control device according to claim 1, wherein the mounting positions of the pressure contact member and the brake shoe are exchanged. (3) The tape tension according to claim 1, characterized in that the tape runs approximately linearly between the tape guide roller provided coaxially with the rotation support shaft and the tension detection member. Control device. (4) The tape tension detecting device according to claim 1, wherein tape tension is detected by a tape tension detecting member and a pressing member. (5) The tape tension detection device according to claim 1, wherein the tape is supplied from the tape tension detection member side. (6) The apparatus according to claim 1, characterized in that the tape is supplied or taken out, or both, in a direction substantially perpendicular to the rotation radius of the tape tension detection arm. Tape tension control device. (7) The tape tension control device according to claim 1, characterized in that a tape tension detection arm, a brake shoe, or a pressure member is provided on the tape loading block. (8) The tape tension control device according to claim 1, wherein the pressure contact member is a rotatably supported roller. (9) The tape tension control device according to claim 1, wherein the tension detection member is a rotatably supported roller.