JPH04195849A - Web automatic loading device - Google Patents

Abstract

PURPOSE:To set a web loading speed at an optimum state by controlling an arm driving motor so that an output pulse obtained from a tachometer disk may be constantly maintained. CONSTITUTION:At a rotational position that corresponds to the threader arm 3 of the tachometer disk 13, slits 15 whose size of width and spacing are differenciated are provided, and the change of a pulse cycle generated from the slits is used as the information of a revolving speed. The difference of a cycle length between the output pulse of the tachometer disk 13 and a reference pulse is sent to a driving circuit 23 of a threader motor, and the threader motor 12 is revolved so that the output pulse and the reference pulse may be synchronized according to the difference of the cycle length. Then, the threader motor 12 is controlled in order for the cycle to be constant. Thus, when the threader arm 3 is revolving, the speed which is optimum at an objective position is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic web loading device. In particular, the present invention relates to an automatic web loading device for guiding a tape leading end from a supply reel to a take-up reel in a magnetic tape device using a replaceable magnetic tape supply reel.

[Prior Art] As a mechanism for guiding the leading end of a web such as a tape along a complicated path, there is, for example, a mechanism described in Japanese Patent Publication No. 13097/1983. This device uses a cam member with a cam groove formed to define a complicated path for the web, and a folding arm whose movement is regulated by the cam member.
A leading block attached to the tip of the web wound around the supply reel is temporarily fixed to the arm and has a mechanism that guides the web to the take-up reel. In addition, as a conventional technique for feeding the tape from the supply reel to the take-up reel, a pulse signal is obtained using a disk provided on the supply reel motor shaft and having slits or sawtooth at regular intervals, and the pulse signal is used to speed up the tape. There is a device that measures the tape speed and controls the active motor of the tape loading mechanism based on the obtained tape speed.

[Problems to be solved by the invention] However, the following problems arise when trying to route the web through a complicated path. If the path is straight, the web movement speed can be determined without considering the material of the web too much, but if the passage is narrow or the web moves through a particularly complex path, it is best to feed the web at a constant speed. Depending on the material, the web may be damaged. However, if the moving speed of the entire mechanism is determined according to the passing portion that requires low speed, the performance of the mechanism will be reduced.

From the above, in order to improve the performance of the apparatus while ensuring the safety of the web, it is necessary to control the speed according to the passing location. In the conventional apparatus disclosed in Japanese Patent Publication No. 59-13097, etc., no consideration is given to controlling the moving speed of the web depending on the position of the passage. It is an object of the present invention to solve one or more of the above problems and provide control so that the web can move at any desired speed at any desired location in a web path that has complex passages.

[Means for Solving the Problems] In order to achieve the above object, a driving system is provided that connects an arm that moves the tape (web) from a supply reel to a take-up reel and a motor that moves the arm. A tachometer disk is provided as a speed information holding member, which corresponds to each rotational position of the arm and whose slit size and slit spacing are set in proportion to the rotational speed. By controlling the arm movable motor so as to keep the output pulse obtained from the tachometer disk constant, the moving speed of the arm tip, that is, the tape tip, can be arbitrarily controlled.

[The arm movement motor is controlled so that the output pulses of the tachometer disk, which is arranged so that the width and spacing of the working coslits correspond to the moving speed of the arm tip, have a constant cycle. This allows the required speed to be obtained when the arm tip is in any position.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a magnetic tape reel-to-reel transfer mechanism of a magnetic tape loading device to which the present invention is applied.

When the tape cartridge 6 is loaded into the apparatus, a leader block 8 provided at the leading end of the magnetic tape 5 is exposed from the tape cartridge 6. The supply reel within the tape cartridge 6 is connected to a supply reel motor 16, and the leader block 8 is connected to a threader arm. The threader arm 3 guides the leader block 8 to the machine reel 7 (take-up reel) while being engaged with the leader block 8. The leader block 8 is pulled out from the tape cartridge 6, and the D bearing 4, the head 5, the D bearing 4, and the tension The outside of each sensor 11 is moved in this order and joined to the machine reel 7. With the movement of leader block 8.

The magnetic tape also moves along the leader block passing route 9.

The leader block 8 is housed in the machine reel 7 while being engaged with the pin 17, and the machine reel 7 performs a winding operation of the magnetic tape. The pin 17 and double lock 8 are separated when the tape is wound onto the tape cartridge 6 and the tape cartridge 6 is unloaded. At that time, the threader arm 3 to which the pin 17 is connected moves in the exact opposite direction to that during loading.

Next, the operation of the threader arm 3 will be explained in detail.

The threader arm 3 having a puncture mechanism is rotated by the threader motor 12, and while the leader block 8 is engaged with the pin 17, the guide roller 10 provided at the tip of the cam linkage 18 moves into the cam groove 2 cut in the cam 1. By moving, the leader block passing route 9 is moved. The leader block passing route 9 is the D bearing 4. This route passes outside the head 5, the D bearing 4, and the tension sensor 11, respectively. After passing outside the tension sensor 11, the threader arm 3 and the leader block 8 are at the position indicated by the dotted line. Finally, the threader arm 3 moves to accommodate the leader block 8 in the dotted line portion within the machine reel 7, completing automatic loading of the magnetic tape from the supply reel to the take-up reel. During this time, the series of operations in which the threader arm 3 transfers the leader block 8 from the tape cartridge 6 (supply reel) to the machine reel 7 (take-up reel) depends on the rotational speed control of the threader motor 12.

FIG. 2 shows the configuration of the means for activating and controlling the operation of the threader arm 3, and a block diagram of the threader motor drive control system in the present invention.

Shaft 19 transmitting driving force from threader motor 12
A threader arm 3, a cam 1, and a tachometer disc 13 are attached to the mount. The order of these installations can be changed. The threader arm 3 rotates in synchronization with the rotation of the threader motor 12. This also applies to the tachometer disc 13. As the threader arm 3 rotates, the guide roller 10 moves along the cam groove 2 on the cam 1, and due to the puncture mechanism of the cam linkage 18 and the threader arm 3, the tip of the threader arm moves toward the shaft 19.
Change the distance from the leader block and pass on the leader block passing route 9. During this time, as the tachometer disk 13 rotates, the detector 14 detects the slit 5, and the pulse generating circuit 20 generates an output pulse.

FIG. 3 shows an embodiment of the tachometer disk 3 according to the present invention.

In the present invention, slits are not provided at equal intervals as in the past, but
Threader arm 3 of tachometer disc 13 - Slin 1-15 with different width and spacing at the corresponding rotational position
is provided, and the resulting change in the pulse period is used as rotational speed information.

The speed at which the tip of the threader arm moves along the leader block passage route 9 is set in accordance with the rotation angle of the threader arm 3. If the required speed at each position of the threader arm is faster, the slits 15 provided at the rotation angle portion of the tachometer disk corresponding to that position are widened and spaced apart.

Furthermore, if the required speed at each position of the threader arm is slow, the slit 15 provided at the corresponding rotation angle portion of the tachometer disk corresponding to the threader arm position narrows the radius and narrows the interval by one. The width and spacing of the slits 15 are proportional to the rotational speed, and the output pulse period that appears during steady rotation of the threader motor is arbitrary for each rotational position, and the length of the pulse period is different for each rotational position. It represents the amount of movement of the arm at a rotational position, in other words, a value proportional to the amount of angular change at each rotational position. Therefore, the pulse period length of the actually obtained output pulse is compared with the reference pulse generated from the reference pulse generation circuit 21 in the pulse period length comparison circuit 22.

The period length difference between the output pulse and the reference pulse is sent to the threader motor drive circuit 23, and the threader motor 12 is rotated so that the output pulse and the reference pulse are synchronized according to the period length difference. By controlling the threader motor 12 so that the cycle T becomes constant as shown in FIG.
The optimum speed can be obtained at the target position while the arm 3 is rotating.

In this embodiment, magnetic tape has been described, but it goes without saying that similar control can be applied to other webs. Furthermore, according to the present invention, even if there is a change in the five set speeds, the speed can be easily set by converting only the tachometer disk.

In addition, the present invention replaces the speed information of the threader arm with the width and spacing of the slits, converts it to the slit arrangement of the tachometer disk, and controls the threader motor so that the tachometer output pulse is constant. The tachometer disk may be replaced by other means, such as a magnetic disk, as long as the output pulses in uncontrolled steady operation change in period length in accordance with changes in speed.

[Effects of the Invention] As described above, according to the present invention, the loading speed of a web such as a magnetic tape can be set to an optimum state, so that the web can be loaded reliably in the shortest possible time, and the web can be loaded in the shortest possible time. Damage can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view of an inter-reel magnetic tape transfer mechanism in a magnetic tape loading device according to an embodiment of the present invention;
This figure shows a block diagram of the late moving portion of the magnetic tape transfer arm and the active control system of the magnetic tape loading device shown in FIG. Third
The figure is a plan view showing the configuration of a tachometer disk according to an embodiment of the present invention. FIG. 4 is a diagram showing tachometer output pulses during active motor control of the magnetic tape transfer arm. , 3... Threader arm, 6... Tape cartridge. 7... Machine reel, 8... Leader block, 9...
...Leader block passage route, 12...Threader-
Motor, 13... Tachometer disk, 14... Detector. 15...Slit, 16...File reel motor. 17...Pin, 20...Pulse generation circuit, 21...
-Reference pulse generation circuit, 22...Pulse period length comparison circuit. 23...Threader-motor comment circuit diagram f

Claims (1)

[Claims] 1. A web feeding means, a web winding means, an arm for transporting the web along a predetermined path, a motor for driving the arm, and arm speed information corresponding to the moving position of the arm. An automatic web loading device comprising: a speed information holding member; and a control means for controlling the rotational speed of the motor based on the speed information from the speed information holding member.