JPS62298962A - Tape drawing-out device - Google Patents

Abstract

PURPOSE:To eliminate the unstable condition of the position of a pulling-out post when a tape is quickly fed by pulling out a magnetic tape from a first position in a cassette by a pulling-out member, abutting to an elastic member fixed to a certain position before turning is completed at a second position, deforming the elastic member, energizing and fixing a pulling-out member in the second position condition. CONSTITUTION:A pulling-out arm 3 starts to turn in a clockwise direction from the first position by a cam gear 7. At this time, the pulling-out arm 3 and a plate spring 10 are separated. Thereafter, the pulling-out arm 3 is abutted to the plate spring 10 by the turning of the pulling-out arm 3 before the turning is completed, thereafter, as the turning is executed, the plate spring 10 is elastically deformed and the pulling-out arm 3 is energized in the counter-clockwise direction. Namely, while the pulling-out arm 3 is at the second position, the pulling-out, arm 3 is energized in the counter-clockwise direction by the plate spring 10, overlapped with a tensile force by a return spring 6 and the larger energizing force is given. Consequently, a pulling-out post 2 prevents the phenomenon that a magnetic tape 1 is operated by a friction force.

Description

DETAILED DESCRIPTION OF THE INVENTION 3. Detailed Description of the Invention Field of Industrial Application The present invention relates to a tape pull-out device useful for magnetic recording and reproducing devices such as audio equipment and video tape recorders.

BACKGROUND OF THE INVENTION In recent years, home-use rotating magnetic recording and reproducing devices using tape cassettes have become increasingly popular as they have become smaller, lighter, and less expensive.

Furthermore, it has been desired that the mechanism of the device has a simple structure and high functionality, as well as a reduction in the number of parts, weight reduction, thickness reduction, and power saving. In addition, in a VHS format video tape recorder, even when fast forwarding or rewinding a recorded magnetic tape by two rewinds, a part of the magnetic tape is pulled out from the cassette and the magnetic head is used to transmit control signals. Products have been manufactured that have the function of a so-called electronic linear time counter (hereinafter referred to as a linear counter), which performs fast forwarding and two rewinding operations in the connected state, and counts and displays the pulses of the control signal. A conventional tape drawing device will be described below with reference to the drawings.

5 and 6 are schematic plan views of a conventional tape drawing device. 1 is a magnetic tape, and 2 is a drawer post which is fixed perpendicularly to the tip of the drawer arm 3. The drawer arm 3 is rotatable around a pivot shaft 5 fixed on the chassis board 4, and is integrated with a cam follower 3a. Reference numeral 6 is a return spring that is attached between a spring hook 6a fixed on the chassis board 4 and a spring hook 3b that is a part of the drawer arm 3, and biases the drawer arm 3 in the counterclockwise direction. ing. A stopper 3C is fixed on the chassis board 4 and locks the drawer arm 3 in a fixed position by coming into contact with the drawer arm 3. A cam gear 7 is rotatable around a cam gear shaft 8 fixed on the chassis board 4, and is driven by a drive source (not shown). The cam gear 7 has an end cam portion 7a. 9 is the control head-t'
6 has a function of transmitting control signals recorded on the magnetic tape 1. Next, the operation of the tape drawing device constructed as above will be explained.

FIG. 5 shows a state in which the magnetic tape 1 is stored in a cassette (not shown), and the drawer post 2 is located inside the magnetic tape 1.

Let this position be the wo1 position. Cam gear 7 depending on the drive source
When the drawer arm 3 rotates counterclockwise, the cam follower 3a of the drawer arm 3 comes into contact with the end cam portion 7a of the cam gear 7 and slides, and the drawer arm 3 rotates clockwise from the first position. When the rotation of the cam gear 7 is completed, the rotation of the drawer arm 3 is completed at the position shown in FIG. This position is defined as the second position. During this operation, the magnetic tape 1 is pulled out from the cassette by the pull-out post 2 and comes into contact with the control head 9 as shown in FIG.

In this state, the magnetic tape 1 is fast-forwarded or rewound, and control signals are transmitted at the same time, so that the magnetic recording/reproducing device functions as a linear counter. Conversely, when the cam gear 7 rotates clockwise from the position shown in FIG. 6, the contact between the cam follower 3a of the drawer arm 3 and the end cam portion 7a of the cam gear 7 is released, and the drawer arm 3 is moved from the second position. Rotates counterclockwise by the return spring,
Rotate to the first position and lock. At the same time magnetic tape 1
is wound up by a reel (not shown) in the cassette and stored in the cassette as shown in FIG.

Problems to be Solved by the Invention However, in the above configuration, the cam follower 3a of the drawer arm 3 contacts the end cam portion 7a of the cam gear 7 in the second position, and is further fixed by the tensile force of the return spring 6. However, the tensile force of the return spring 6 cannot be made so strong as to reduce the driving force of the pull-out arm 3. In such a case, when the magnetic tape 1 is being wound rapidly from the left reel to the right reel, the pull-out arm 3 is pulled clockwise by the frictional force between the magnetic tape 1 and the pull-out post 2, and the pull-out arm 3 is pulled clockwise by the pull-out post. There was a problem that the position of No. 2 moved or was photographed. The distance between the point of action of the cam follower 3a of the drawer arm 3 and the pivot shaft 5 is a lever ratio that is quite small compared to the distance between the drawer post 2 and the pivot shaft 6, so the drawer post 2 is moved by a light frictional force. It moves. If the position of the drawer post 2 becomes unstable in this way, the tension of the magnetic tape 1 will fluctuate, making the contact between the magnetic tape 2 and the control head 9 unstable, and therefore, the magnetic tape 1 will not be recorded during fast forwarding. This results in inaccurate readings of the control signals, reducing the accuracy of the linear counter and impairing its functionality.

In order to solve these problems, the present invention uses a simple mechanism to stabilize the fixed position of the drawer post 2, accurately read the control signal of the magnetic tape 1 during fast forwarding, and improve the accuracy of the near counter. The purpose of the present invention is to provide a tape drawing device that can

Means for Solving the Problems In order to solve the above-mentioned problems, the tape drawing device of the present invention provides that after the drawing member starts rotating while drawing out the magnetic tape from the first position in the cassette, Before the rotation is completed at the position, it comes into contact with an elastic member fixed at a certain position,
In the second position where the magnetic tape is brought into contact with the control head and rotation is completed, the elastic member deforms to bias and fix the drawer member.

The present invention uses the above-described mechanism to eliminate the unstable position of the tape pull-out post during rapid forwarding of the magnetic tape, and to reliably read the control signal of the magnetic tape, thereby improving the accuracy of the linear counter. It is possible to realize a tape drawing device with improved performance.

Embodiment Hereinafter, a tape drawer device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic plan view of a tape drawing device according to an embodiment of the present invention, and FIGS. 2 to 4 are explanatory diagrams of the operation of a part of the device viewed from the side. Note that the same components as those in the conventional example described above are given the same numbers and their explanations will be omitted.

The main components of the tape drawer according to the embodiment of the present invention are the same as those of the conventional tape drawer shown in FIGS. It has a leaf spring 1o fixed to. As shown in FIGS. 1 and 2, the leaf spring 10 is fixed on the chassis board 4, and the portion other than the fixed surface is elastically deformable. The operation of the tape drawing device according to the embodiment of the present invention having the leaf spring 10 configured as described above will be described below.

FIG. 1 shows a state in which the pull-out arm 3 is in the second position, pulling out the magnetic tape 1 from the cassette and bringing it into contact with the control head 9. At this time, the tip of the drawer arm 3 is in contact with the leaf spring 1oKa.

The process leading to this state will be explained. First, the drawer arm 3 starts rotating clockwise from the first position by the cam gear 7. At this time, the drawer arm 3 and the leaf spring 1o are separated as shown in FIG. Thereafter, as the drawer arm 3 rotates, the drawer arm 3 comes into contact with the leaf spring 1° before the rotation is completed as shown in FIG. The rotation is completed at the second position, which is the state shown in FIG. This is the position corresponding to FIG. At this time, the leaf spring 1o is elastically deformed and biases the drawer arm 3 in the counterclockwise direction. Conversely, when the drawer arm 3 is rotated counterclockwise from the second position, the leaf spring 1o returns to its original shape according to the rotation, and the contact with the drawer arm 3 is released, and the drawer arm 3 returns to the first position, and the magnetic tape 1 is stored in the cassette). That is, when the drawer arm 3 is in the second position, the drawer arm 3 is biased counterclockwise by the leaf spring 10 as shown in FIGS. 1 and 2, and the pulling force by the return spring 6 is applied. A large biasing force is applied by overlapping with the above. Therefore, it is possible to prevent the pull-out post 2 from moving due to the frictional force generated when the magnetic tape 1 is rapidly forwarded. The pull-out arm 3 receives a force from the leaf spring 1o just before the rotation for pulling out the magnetic tape 1 is completed at the second position.
Since the pressure angle with a is sufficiently small, the increase in the driving force of the drawer arm 3 is sufficiently small.

The tape drawing device configured as described above has a plate spring 1
0 can apply a necessary and sufficient counterclockwise biasing force to the pull-out arm 3 in the second position, and the pull-out post 2 due to the frictional force when rapidly forwarding the magnetic tape 1 can be applied to the pull-out arm 3 in the second position.
The unstable state of the position of the magnetic tape 1 can be eliminated, and the control signals of the magnetic tape 1 can be reliably read. Therefore, the accuracy of the linear counter can be improved.

Effects of the Invention As described above, in the tape drawer of the present invention, after the drawer member starts rotating while drawing out the magnetic tape from the first position in the cassette, but before the rotation is completed at the second position. When the magnetic tape comes into contact with an elastic member fixed at a certain position, and the rotation is completed when the magnetic tape comes into contact with the control head, the elastic member deforms and biases the drawer member to fix it. By providing this mechanism, it is possible to eliminate the instability of the position of the drawer post due to frictional force when rapidly forwarding the magnetic tape, and to reliably read the control signal of the magnetic tape. Therefore, it is possible to realize a tape drawer that improves the accuracy of the video tape recorder's glue near counter, and the effect is very large.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view of a tape drawing device according to an embodiment of the present invention, FIGS. 2 to 4 are side views of main parts for explaining the operation of the device, and FIGS. 5 and 6 are conventional FIG. 3 is a schematic plan view of the tape drawing device. 1...Magnetic tape, 2...Drawer post, 3...Drawer arm, 4...Chassis board, 5...Rotation support Shaft, 6... Return spring, γ... Cam gear, 8... Cam gear shaft, 9... Control head, 10...
...Plate spring, 3a...Cam follower, 3b.
...Spring hook, 3C...Stopper, 6
a...Spring hook, 7a...End cam part.

Claims (1)

[Claims] a pull-out member that rotates back and forth between a first position in the cassette and a second position where the magnetic tape is brought into contact with a magnetic head for recording and reproducing signals; After starting the rotation from the second position, before the rotation is completed at the second position, it comes into contact with an elastic member fixed at a certain position, and when the rotation is completed, the elastic member deforms and attaches the drawer member. A tape drawing device characterized by being equipped with a force and fixing mechanism.