Abstract:
A record reproduction apparatus having a loading member operative to pull a tape out from a tape cassette for winding around a rotating head drum wherein a clutch mechanism transmits a rotating force of the loading member to a tape reel stand depending on the rotating direction of a loading ring so that a transmission of the rotating force by the clutch mechanism occurs only during unloading of the tape and not during fast forwarding and rewinding of the tape.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a tape loading and unloading mechanism of a taped record reproduction apparatus of the cassette type in which a tape is pulled out from a cassette and is wound around a rotating head drum at a prescribed position thereof for recording and reproducing video signals, etc. 
     2. Description of the Prior Art 
     During the unloading operation of a magnetized tape which has been pulled out from a cassette whereby the tape is housed again into the cassette in the video tape recorder (VTR or VCR) of a cassette type, in general, it is necessary that a tape pull out member be retracted into a cassette opening and that at the same time either or both of a feeding reel or a rewinding reel within the cassette be rotated in a tape take-up direction, in order for the magnetized tape, which has been slackened, to be wound back into the cassette. When such an operation is performed at the time of unloading, in a conventional apparatus a complicated mechanism is required to detect the unloading state in order for a take up idler to be engaged with or disengaged from the reel. 
     SUMMARY OF THE INVENTION 
     The present invention is intended to provide a record reproduction apparatus in which the shortcoming of conventional devices mentioned above can be eliminated. 
     Also an object of the present invention is to provide a simple arrangement for record reproduction apparatus which can prevent slack or sag of a tape which accompanies an unloading operation. 
     Also, another object of the present invention is to provide a record reproduction apparatus which does not create undesirable influence over high speed tape forwarding. 
     According to an embodiment of the present invention, engagement and disengagement of a clutch, which transmits a driving force to tape take up means at the time of unloading, are controlled in accordance with the rotating direction of loading means, and the driving force of the take up means can be utilized by the loading means, tape take up action at a time of unloading can be accomplished in a secure manner. 
     Also according to an embodiment of the present invention clutch means to effect a change over control of transmission of a driving force to the take up means by a shifting of the direction of the loading means are provided, whereby the take up means are driven only in an association with an unloading operation, thereby avoiding inconvenience at the time of loading. 
     Also according to an embodiment of the present invention a friction member is provided at a part of the transmission means, whereby malfunction seldom occurs even when an excessive load, etc. is applied on the apparatus. 
     Further, according to an embodiment of the present invention, an arrangement is employed whereby at a high speed running mode of a tape, the tape is at once placed in an unloading state and at the same time transmission of a driving force from loading means to take up means is cut off along with said placing of the tape in the unloading state, whereby the present invention can be applied in the tape high speed running mode without any difficulties. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 and FIG. 2 are simplified schematic diagrams showing a loading mechanism as an example of a record reproduction apparatus according to the present invention. 
     FIG. 1 shows the state in which loading is completed, and 
     FIG. 2 shows the state in which unloading is completed. 
     FIG. 3 is an enlarged plan view to show an arrangement around a feeding reel stand in the apparatus of the present invention. 
     FIG. 4 is an enlarged side elevation of the component portion shown in FIG. 3. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 1 and FIG. 2 show an example of a magnetic record reproduction apparatus in which the present invention is employed. The apparatus shown in the drawings is a loading mechanism including a loading ring for a VTR (VCR), wherein the loading operation of the apparatus in the drawings is of a known type, and thus only a simple outline thereof will be provided. In the drawings, 1 is a cassette which has a tape feeding reel 2 and a take-up reel 3 therein, wherein a magnetized tape is wound from the feeding reel 2 to the take up reel 3 along one side of a cassette. A ring 4 operates as loading means and rotates in a counterclockwise direction at the time of loading and rotates in a clockwise direction at the time of unloading. A rotation head drum unit 5 and a pinch roller 6 rotate together with the loading ring when loading is completed (FIG. 1) and are positioned near a capstan 11. The system includes a sound recording and reproduction head 7, a total width erasing head 8, a guide pole 9 mounted on the loading ring, and a loading arm 10. 
     A loading operation is performed first by pulling out the tape at a first running path within the cassette 1 with the pinch roller 6 and a forward guide by a counterclockwise rotation of the loading ring 4. The tape is then pulled out from the cassette to the left by a counterclockwise rotation of the loading arm 10 in association with rotation of the loading ring 4 whereby the tape is brought into contact with the total width erasing head 8. The pinch roller 6 is positioned near the capstan 11 which is positioned on a base plate and at the loading completion position of FIG. 1. The tape is held between the pinch roller 6 and capstan 11 so that the tape is made to run. 
     Next, at the time of unloading, the loading ring 4 is rotated in a clockwise direction opposite to the direction of rotation at the time of a loading operation to return it to the condition of FIG. 2 from the condition of FIG. 1. As the tape is slackened at this time it is necessary to take up the slack to the reel 2 or the reel 3 within the cassette 1 as the take up means. While the example shown in FIGS. 1 and 2 indicates a situation in which this slackened tape is taken up by the feeding reel 2, taking up of the tape at the time of unloading may be effected either by the feeding reel 2 or by the take up reel 3 or by both. 
     FIG. 3 is an enlarged plan view to show the arrangement near a feeding reel stand 13 in the above-mentioned example of the present invention. FIG. 4 is an enlarged sectional side elevation of the component portion shown in FIG. 3. 
     In these drawings the loading ring 4 rotates in the clockwise direction (shown by an arrow) at the time of unloading and a gear 14 is rotated in the counterclockwise direction by a gear part provided at an outer circumference of the ring. The gear 14 is axially supported by a shaft 25 mounted on the base plate in a rotatable manner. A clutch arm 17 is fixed at a part of said shaft 25 with a bearing boss part 18 while a take up idler shaft 20 is fixed at the other end. The bearing 18 is rotatably attached to the shaft 25 and by cooperation of a wave washer 15 and a washer 16, it is restrained in a thrust direction by an E ring 26. The gear 14 and the clutch arm 17 are friction coupled by a spring force of said wave washer 15. Further, an idler 19 is rotatably attached to the shaft 20. The idler 19 has an elastic member 19a which may be formed of rubber at the outer periphery of its larger diameter circumference and it has a gear 19b at the shaft thereof, wherein said gear 19b and the gear 14 are in an engaged state. Thus the gear in the ring 4, the gears 14, 19b and the elastic member 19a consist of transmission means. 
     Therefore, when the loading ring 4 rotates in the clockwise direction at the time of unloading, the gear 14 rotates counterclockwise and the clutch arm 17 which is friction coupled with said gear 14 also rotates counterclockwise. As a result, the take up idler 19 is brought into pressure contact against an outer circumference of the feeding reel stand 13. When the pressure contacting direction of the idler 19 against the feeding reel stand 13 is in a thrusting direction, the rotation of the idler 19 is transmitted to the reel stand 13 and the reel stand 13 rotates in the counterclockwise direction which is the tape take up direction, and thus the tape which has been slackened at the time of unloading is taken up. 
     Also, since the rotation of the reel stand 13 is stopped at the same time that the rotation of the loading ring 4 is stopped as the unloading is completed, it is not necessary to change over the clutch. Further, if the take up rotation number is set somewhat higher than the rotation number actually required for take up and the reel stand 13 and a reel spindle 13a are made to friction couple with each other, the possibility of leaving excess tape will be eliminated. Also when loading is effected after the unloading is completed, while the take up idler 19 is in contact with the outer circumference of the reel stand 13, the clutch arm 17 rotates clockwise in a reverse direction to that during operation at the time of unloading as the counterclockwise rotation of the loading ring 4 at the time of the loading is started. The take up idler 19 separates from the outer circumference of the reel stand 13 and comes in contact with a stopper (not shown) and is stopped by a slight movement thereof. Further, since there is no load on the take up idler 19 while the loading operation is performed, the loading operation can be effected without difficulties. 
     Next, when the take up idler 19 comes in contact with the outer circumference of the reel stand 13 during high speed running such as during tape fast forwarding take up, etc., a braking action is effected whereby at the time of fast forwarding and rewinding, it is necessary to keep the take up idler 19 out of contact with the reel stand 13 in an association with said braking. This is done by shifting a slider 23 to the right in association with the above-mentioned fast forwarding and rewinding operations thereby rotating a lever 21 in the counterclockwise direction by a pin 23a mounted on the slider 23. This will cause checking of a fore end part 20a of the take up idler shaft by one end 21a of the lever 21, thus keeping the take up idler 19 from coming in contact with the outer circumference of the reel stand 13. 
     As has been explained above, in the magnetic record reproduction apparatus of the present invention a take up operation at a time of unloading can be securely performed by a simple arrangement, and an apparatus, which can secure stable operation without requiring a complicated mechanism as in a conventional method, can be obtained, thus providing great advantages.