GB1565314A

GB1565314A - Recording tape transport mechanism

Info

Publication number: GB1565314A
Application number: GB2880777A
Authority: GB
Original assignee: Clarion Co Ltd
Current assignee: Faurecia Clarion Electronics Co Ltd
Priority date: 1976-07-09
Filing date: 1977-07-08
Publication date: 1980-04-16
Also published as: DE2730961B2; SE7707827L; AU511585B2; SE425443B; NL171208C; DE2730961C3; AU2690977A; NL7707621A; DE2730961A1

Description

(54) RECORDING TAPE TRANSPORT MECHANISM (71) We, CLARION COMPANY LIMITED, a Japanese Company, of No. 535-2, Hakusan, Bunkyo-ku, Tokyo, Japan, do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement:- This invention relates to a recording tape transport apparatus for use in a tape recording and/or playback apparatus.

In a tape recorder, it is necessary to stop the running of the tape when the end of the tape is reached or under such abnormal conditions as bulging out or tangling of the tape in order to assure correct operation and to prevent damage or breakage of the tape as well as fault of the mechanical portions. Although various electrical and mechanical quick stopping devices have been used they are not always satisfactory.

For example, according to an electrical stopping device, disclosed in U.S. Patent No. 3488019, as the cessation of rotation of a reel driving member is electrically detected for actuating a tape stopping device, when the reel driving member is caused to rotate in the reverse direction due to tangling of the tape it would be impossible to produce a stop signal with the result that the tangling becomes more severe. On the other hand, since in a known mechanical stopping device, the abnormal condition is detected by the abnormal tension of the tape it is impossible to detect such abnormal condition as the bulging which does not accompany any abnormal tension of the tape. Moreover, as the abnormal condition is detected on the assumption that the tape runs at a constant speed it is impossible to detect the abnormal condition and to stop the tape under a high speed tape running condition which is several times larger than the recording or reproducing speed. For this reason, it is impossible to use a sufficiently high running speed as desired. As above described since detection of the end of the tape is difficult under the high speed running condition when the tape is locked under high speed running condition, it is impossible to unlock the tape by detecting the tape end so that it is necessary to stop the high speed running by manually depressing a button. Moreover, it is necessary to repeat several times the stopping and the starting of the high speed running as the tape end is reached. In the prior art automatic stopping device, it is liable to be held at the stopped state after the tape has stopped so that restarting of the tape cannot be made smoothly.

It is an object of this invention to provide an improved recording tape transport mechanism provided with an automatic stopping device.

According to the invention there is provided a recording tape transport mechanism provided with an automatic stopping device comprising a detection arm mechanically operated in response to stopping of rotation of a tape reel driving sprocket, a member connected to the detection arm through a connecting rod and a spring to be rotated according to the movement of the detection arm, a latch member pivotally connected to the said member to be moved thereby and provided with an engaging member at an end thereof, and a plurality of engageable members provided on a flywheel rotated by a driving motor to transmit rotation to the reel driving sprocket, one of the engageable members engaging the engaging member of the latch member to directly stop the rotation of the flywheel when the latch member is moved in response to stopping of rotation of the reel driving sprocket.

Preferably the said member connected to the detection arm is a switch operating member whereby the driving motor is switched off when the detection arm is mechanically operated in response to stopping of rotation of the reel driving shaft.

Preferably the improved tape transport mechanism includes a high speed running locking mechanism and an abnormal tape condition detecting device which not only stops the running of the tape upon occurrence of an abnormal condition but also releases the high speed running locking mechanism. Further switching the running speed of the tape between normal speed and high speed may be facilitated.

In a preferred embodidment a tape cassette may be loaded on to a reel drive sprocket by use of an elevating platform, a pinch roller and a tape transducing head being moved to their operative position in response to the loading of the tape cassette.

This embodiment has a simple and compact means for releasing the tape high speed running condition and the ejection operation by a single operation.

In order that the invention may be more readily understood a specific embodiment thereof will now be described with reference to the accompanying drawings in which: Figure 1 is a plan view of a tape recorder incoporated with a tape stopping apparatus of this invention Figure 2 is a bottom plan view of the tape recorder shown in Figure 1; Figure 3 is a lefthand side view of the tape recorder shown in Figure 1; Figure 4 is a righthand side view; Figure 5 is a bottom side view; Figure 6 is a top side view, respectively of the tape recorder shown in Figure 1.

Figure 7 is an exploded perspective view showing various component elements of the tape recorder; Figure 8 is an exploded perspective view showing the elevating platform and the elements associated therewith, and Figure 9 is an exploded perspective view showing driving and driven members.

Referring now to the accompanying drawings, more particularly Figure 7, a stationary deck 1 is provided with an opening 12 for a capstan, an opening 18 for a reel driving member, an opening 13 for receiving an engaging member, an opening 14 for a main shaft 44, an opening 16 for another shaft 131, and an opening 17 for a pin. A rear plate 19 provided with a recess 19a is secured to the rear side of the deck 1 for defining a region 110 for mounting a driving motor.

An elevating platform 2 shown in Figure 8 is movably secured to the bottom of the stationary deck 1. A guide frame 3 is mounted on the stationary deck so that a magnetic tape cassette 300 may be loaded into the space between the deck 1 and the frame 3. Both end walls of the deck 1 are bent downwardly as at 11 and a sliding frame 4 is provided to slide along the inner side of the fore end wall 11. Each end wall Il is provided with a pair of inclined guide slots 111 near both ends thereof for receiving guide members 40 secured to the elevating platform 2. The guide members 40 also fit in vertical guide slots 41 near both ends of the sliding frame 4 to guide the same. The sliding frame 4 is provided with horizontal guide slots 42 in a direction perpendicular to the vertical guide slots 41 for receiving guide members 43 mounted on the end wall 11 of the stationary deck 1, thereby guiding the sliding frame 4 in the horizontal direction.

A head plate 5 shown in the upper portion of Figure 7 is mounted on one side portion of the deck 1 not covered by the guide frame 3 and a pinch roller supporting frame 55 is superposed on the head plate 5. The assembly of the head plate 5 and the pinch roller supporting frame 55 is mounted on the stationary deck 1 and a vertical main shaft 44 secured to the sliding frame 4 extends through openings 51 and 54 at one end of the head plate and the pinch roller supporting frame respectively, the portion of the main shaft 44 extending below the sliding frame 4 being received by a guide member 25 at one end of the elevating platform 2 for guiding the vertical movement thereof. Internally threaded supports 50 are secured near the lefthand side of the head plate 5 and a magnetic pickup head 150 is secured to the supports 50 by screws 250 and 251 through a spring 155 so as to adjust the azimuth and height of the pickup head. One side of the head plate 5 is bent up as at 52 to face a pinch roller 56 with a suitable spacing therebetween. The lead wires, not shown, to the pickup head 150 are clamped to the upper edge of the bent up side wall 52 whilst leaving a sufficient space below the wires and against the rest of the side wall for accumulating the tape from the pinch roller, as described below. The head plate is also provided with a guide groove 53 for receiving a roller 132 carried by a pin 131 at one end of a pivoted arm 130 to be described later. The roller 132 is also received in a slot 57 formed at one end of the base of the frame 55. At about the centre of the upper plate of the frame 55 there is provided a slot 58 for receiving a tape guide 59 made of a synthetic resin which functions to guide the tape and to prevent tangling therof.

A spring 102 is connected between an upward projection 134 of the pivoted arm 130 and an anchor 151 formed on the pinch roller frame 55. Resilience of the spring 102 is applied to both the pinch roller frame 55 and the head 150.

The tape guide 59 is provided with a suitably curved guide surface 159 for guiding a portion of the tape if it is forced out by the pinch roller 56 and moved toward the outside of the stationary deck with respect to the main shaft 44 by utilizing a space between the guide surface and the side wall 52 thus storing the tape at this portion. The tape guided in this manner is then returned to the cassette via the guide surface 159. In this example, the side wall 52 of the head plate 5 is assembled to extend along the pinch roller frame 55. However, such side wall may be provided for the pinch roller frame. Furthermore instead of connecting one end of the spring 102 to the head plate 5, it may be connected to the stationary deck 1 or to the casing containing the same.

The spring anchor 151 is formed on an arm 153 at one end of the pinch roller frame 55, the arm 153 extending to the ouside of the bent up side wall 52 of the head plate 5 so as to engage the side edge 52a of the side wall 52 in the assembled condition shown in Figure 1 in which the pinch roller plate 55 is mounted on the head plate 5.

The force of spring 102 acting upon the arm 153 urges the pinch roller frame 55 and the head plate 5 to rotate in the clockwise direction about the main shaft 44. This biasing force is controlled by the roller 132 supported by the pivoted arm 130, the roller 132 being received in groove 53 and slot 57.

The pivoted arm 130 is normally biased to rotate in the counterclockwise direction by the spring 102. When the moving frame 4 is advanced, its angled shoulder 400a, which contacts the roller 132, allows the arm to rotate counterclockwise until the roller comes into contact with the inner end of the slot 16 in the deck 1.

The guide members 40 are secured to opposing seats 20 which are provided for both sides of the elevating deck 2. Each guide member 40 extends through a respective one of the guide slots 111 on both sides of the stationary deck 1 and two of the members 40 also extend through respective ones of the vertical guide slots 41 of the sliding frame 4 for guiding the movement of the elevating platform 2 and the sliding movement of the sliding frame 4. A driving motor 120 is secured to a portion 21 of the elevating platform 2 by means of screws 220.

A raised portion 22 is formed at the central portion of the elevating deck 2 for mounting driving and driven members (to be described later) on its lower surface. A bottom plate 6 is secured to the lower surface of the raised portion 22 by means of screws 226 for defining a compartment for accommodating the driving and driven members including a flywheel 125 provided with a capstan 126, a rotary driving member 66 provided with a reel driving sprocket 65 for supporting a take up reel (not shown), and intermediate rotary members 81 and 82.

The flywheel 125 is driven by a pulley 221 rotated by the motor 120 through a belt 127.

The intermediate rotary members 81 and 82 mounted on an idler plate 8 are switched by depressing an operating member 80 of the idler plate 8. More particularly, under normal conditions, by the tension of a tension spring 83 connected between the idler plate 8 and the elevating platform 2, the intermediate rotary member 81 having a relatively large diameter is interposed between a small diameter portion 125a of the flywheel 125 and the driving member 66 for running the tape at a speed suitable for normal recording or reproducing. However, when the idler plate 8 is depressed by the operating member 80 against the force of the spring 83, an idler gear 82 mounted on a high speed shaft 84 is interposed between the periphery of the flywheel 125 and the driving member 66 thereby enabling high speed running of the tape. a pin 23 having a reduced diameter portion 23a at the lower end is mounted on the elevating platform 2. The pin 23 as well as the reel driving member 65 are used to received a reel of a well known cassette tape pack.

Another pin 27 is mounted on the elevating platform 2 on the same side as the pin 23 for pivotally mounting one end 70 of an unlocking arm 7 by means of a fixture 75.

Guide members 28 and 29 are secured on both sides of the pin 23, the former being received in a notch 78 at one end of the unlocking arm 7 and the latter in a slot 85 of the idler plate 8.

Guide pins 31 are secured to the upper surface of the guide frame 3 shown in Figure 7 to be slidably received in slots 190 of an election slider 9 provided with a member 90 for mounting an operating button, not shown. A tension spring 92 is connected between a lug 91 of the ejecting slider 9 and a lug 32 of the guide frame 3 whereas a tension spring 46 is connected between another lug 33 of the guide frame 3 and a lug 48 of the connecting member 45 at the front end of the sliding frame 4 as shown in Figure 1. The sliding frame 4 is pushed forwardly i.e. to the right in Figure 7 against the bias of a spring 101 connected between the stationary deck I and one of the guide members 40, when a cassette is loaded in the guide frame 3 to actuate the elevating platform 2. To this end the vertical connecting member 45 is provided with an engaging surface 47 which is engaged by the cassette on insertion thereof in the guide frame 3.

The rear edge 93 of the ejecting slider 9 is adapted to engage the front end 96 of an ejecting link 95 shown in Figure 7. The connecting member 45 is also provided with a lug having a switching member 310. When the cassette, on insertion, pushes forward the member 45 the switching member 310 contacts and depresses projecting button 2001a of ON-OFF switch 2001. On depression of the buttom 2001a the tape recorder is switched ON. The switched OFF position of the switching member 310 and the button 2001a can be seen in Figure 1.

The ejecting link 95 is pivotally mounted on the pivot shaft 15 on the stationary deck 1, and a spring 98 surrounding the pivot shaft 15 is connected between a lug 34 of the guide frame 3 and a lug 97 of the link 95 for normally biasing the same in the counterclockwise direction as viewed in Figure 1. A projection 96a at the front end 96 of the link 95 engages a notch 35 of the guide frame 3 for holding the front end 96 at a position opposing the rear edge 93. When the ejecting lever 9 is pushed towards the right, the ejecting link 95 is rotated about pivot shaft 15 for ejecting the cassette. A pin 99 depending from the ejecting link acts on an arm 118 of a locking plate 113, described in more detail below. The arm 118 rotates the locking plate which thereby releases the sliding frame 4. The latter moves back to the left under the action of spring 101, ejecting the cassette by means of engaging surface 47.

There is provided a high speed running control member 10 having a recess 10a at one end for mouting an operating button.

the control member is provided with slots 136 adapted to recieve guide pins 137 and 138 secured to the bottom of the stationary deck 1. The pivoted arm 130 and a high speed running arm 133 are mounted on the pin 137 on the lower side of the deck. A high speed running locking plate 140 is pivotally mounted on the upper surface of the stationary deck 1 by means of a pivot pin 144 about which it is pivotally urged by spring 146. The pivot shaft 15 extending through the stationary deck 1 pivotally supports the centre of the locking plate 113 on the lower side of the deck 1. The locking plate 113 is provided with four arms 116, 117,118 and 119a. The arm 116 is adapted to engage the main shaft 44 to hold the sliding frame 4 in its advanced position when the latter is moved forwards by insertion of a cassette. The arm 117 is adapted to engage a stop 119 at the rear edge of the stationary deck 1 and cooperates with the operating member 183 of a switch releasing member 180 (Figure 8) to be described later. The arm 11 9a is connected to the hole 162 of the stationary deck 1 through a spring 112a, to urge the locking plate 113 in the counterclockwise direction. The remaining arm 118 cooperates with the projection 99 of the ejecting link 95 for unlocking the locking member 113 from the main shaft 44 when the link 95 is rotated by the ejecting slider 10.

The high speed running control slider 10 is provided with a pin 139 adapted to cooperate with a locking member 141 formed at one end of the high speed running locking plate 140. The pin 139 is received in a notch 104 on the lefthand side of the stationary deck 1 for cooperating with the locking member 141, as shown in Figure 5.

A spring 135 is connected between a lug 10b of the control slider 10 and an opening 133b at in intermediate point of the high speed running lever 133. A tension spring 145 is connected between a lug 129 of the lever 133 and a lug 113 depending from one side of the stationary deck 1. A bent up portion 142 is provided on one side of the high speed running locking member 140 for engaging an operating member 94 formed by downwardly bending one edge of the election slider 9. A bent up edge 143 of the locking member 140 is adapted to engage the lefthand edge 5a of the head plate 5 for limiting the counterclockwise rotation of the locking member 140 caused by the spring 146 at the time of ejection thereby retracting its locking member 141 from the path of the pin 139. The high speed running control arm 133 is provided with a downward projection 148 having an arcuate edge 149, and an upright projection 147 adapted to engage a projection 86 at the lefthand end of the idler plate 8. When a tape cassette is loaded and the elevating platform 2 is raised, depression of the high speed running control slider 10 results in the rotation of the control arm 133 through spring 135. Accordingly, the projection 147 engages the projection 86 of the idler plate 8 for establishing the high speed running condition by interposing the intermediate rotary member 82. When the operating member 10 is fully advanced, the pin 139 is locked by the locking member 141 thus maintaining the high speed running condition. Under this condition, the member 142 of the locking plate 140 is brought to face the operating member 94 of the ejecting slider 9 so that when the ejecting slider 9 is depressed, the high speed locking plate 140 will be rotated in the clockwise direction about shaft 144 for disengaging the locking member 141 from the pin 139 thus releasing the high speed running condition. As the ejecting slider 9 is further depressed, its righthand edge 93 engages the ejection link 95 thereby ejecting the tape cassette as above described.

The pivoted arm 130 is normally biased to rotate in the counterclockwise direction by the spring 102 thus urging the roller 132 on the righthand end of the sliding arm 130 against the lefthand edge of the groove 53 of the head plate 5. As the high speed running control slider 10 is advanced, the inclined surface 152 at one end thereof engages the roller 132 to rotate the pivoted arm 130 in the clockwise direction and the roller extending through the groove 53 rotates the head plate 5 in the counterclockwise direction thus causing the head 150 and the pinch roller 56 to disengage the tape. The upper edge 147a of the projection 147 of the arm 133 engages the bottom surface of a slightly raised portion 201 of the stationary deck 1 whereas the arcuate edge 149 is guided by the downwardly bent member 86 of the idler plate 8 secured to the elevating platform 2 when it is lowered to the inoperative position until the member 81 is stopped by the stop 154 of the arm 133.

During vertical movement of the elevating platform the arcuate shape of edge 149 allows contact to be maintained with the downwardly bent member 86.

As shown in Figures 1. 2 and 6, a L shaped leaf spring 106 made of phosphor bronze, for example, is secured to the rear plate 19 by means of a screw 107. The free end 108 of the leaf spring 106 is bent toward the inner side of the stationary deck 1. A downward bending portion is provided at the rear edge of the elevating platform 2. A slot 123 is provided at said bending portion so as to receive the free end 108 of the leaf spring 106 when the elevating platform 2 is raised and forwarded by the sliding frame 4 through guide members 40 and grooves 111 when the cassette is inserted.

When the leaf spring 106 engages the notch 123 and the ejection link 95 is rotated by the depression of the ejection slider 9 to actuate the locking plate 113 by the downwardly projecting pin 99 of the ejecting link 95, the arm 116 of the locking plate 113 is thereby disengaged from the main shaft 44 carried by the sliding frame 4.

Then the elevating platform 2 is returned to the lower position by the action of spring 101 provided between the deck 1 and one of the rollers 40. When the elevating platform 2 descends the spring 106 disengages from the notch 123.

As above described when the elevating platform 2 is raised to the reproducing position, the leaf spring 106 engages the slot 123 so as to firmly hold the platform 2 at the reproducing position against vibration or shock, Engagement between the leaf spring and the slot also establishes an electrical circuit extending through the deck 1 and the platform 2.

As shown in Figure 8, the flywheel 125 is provided with a plurality of pins or projections 128 about capstan 126. The rotary driving member 66 mounted on the shaft 61 secured to the bottom plate 6 is provided with an integral eccentric cam 67.

A reel driving sprocket 65 is keyed to the shaft 61. The eccentric cam 67 is provided with a projection 68 on its upper surface. As shown by the exploded view Fig. 9, beneath the rotary driving member 66 is provided a motion transmission disc 163 which is secured to the reel driving sprocket 65 through a polygonal opening. A friction disc 161 is interposed between the disc 163 and the rotary driving member 66 so as to rotate them as an integral unit. A spring 164 is interposed between the lower end of the reel driving sprocket 65 and the rotary driving member 66. A driving member 167 is coupled to the motion transmission disc 163 through another friction disc 166 and urged to the bottom of the driven member 167 by a securing member 165 through a spring plate 169. An upward projection 168 extends in parallel with the reel driving sprocket 65 along one side of the rotary driving member 66. The spring 164 functions to ensure the frictional engagement between the friction discs 161 and 166 and cooperating members.

However, the materials of these members are selected so that the frictional coupling force between the friction disc 166 and the driven member 167 is much smalier than that between the friction disc 161 and the driving member 66. For example it is advantageous to construct the driving member 66 with a synthetic resin and the driven member 167 with metal.

Alternatively, the surface of the friction disc 166 in contact with the driven member 167 may be coated with a friction decreasing coating for decreasing the frictional force so that the friction may be overcome by slight resistance.

An opening 174 of a detection plate 73 which is pivotally mounted on the unlocking arm 7 at a point 71 suitably spaced from its pivoted end 70 receives the projection 168 of the driven member 167. At the central portion of the detection plate 73 is formed an opening 172 having a size sufficient to accommodate the reel driving sprocket 65 and the eccentric cam 67 mounted therebelow. One side 177 of the opening 172 is adapted to engage the eccentric cam 67 and the opposite side is formed with a shoulder 178 that engages the projection 68 on the eccentric cam 67. On the righthand side of the detection plate 73 is formed an arcuate slot 176 having the same centre as the opening 175 for pivotally mounting the detection plate 73. The slot 176 receives a pin 76 near the righthand end of the unlocking arm 7.

A connecting member 72 at the free end of the unlocking arm 7 is provided with a circular opening 74 and a slot 79. A spring 208 is connected between a lug 209 on the elevating platform 2 and a pin 185a on the switch releasing member 180 which is pivotally mounted on the elevating platform by a pivot pin 26. The switch releasing member 180 is connected to the opening 79 through a connecting rod 181. A spring 182 is connected between the opening 74 of the unlocking arm 7 and an opening 184 of the member 180, which spring extends in parallel with the connecting rod 181.

Another spring 124 is provided between the connecting member 72 and a lug 24 of the elevating platform 2 for normally biasing the unlocking arm 7 in the clockwise direction.

The springs 182 and 124 may be connected to either one of the openings 74 and 79 depending upon their relative strength. It is advantageous to suitably construct the connecting member 72 so as to facilitate correction of its manufacturing error. For example, a narrow neck 77 may be provided for the connecting member 72 so that it can be adjusted by bending it at the narrow neck 77. When the switch releasing member 180 is operated a switch for the driving motor 120 is opened to stop the operation of the tape recorder, or to stop the operation of the flywheel 125. A projection 183 of the switch releasing member 180 is provided for this purpose.

To stop the flywheel 125 by the switch releasing member 180, a pivot pin 185 is provided on the member 180 for pivotally supporting one end of a latch member 186.

A spring 187 surrounding the pivot pin 185 is interposed between the projection 183 of the member 180 and a lug 188 of the latch member 186 for urging the same in the clockwise direction. At one end of the latch member 186 is provided a depending projection 189 for engaging one of the pins 128 of the flywheel 125. The projection 183 of the switch releasing member 180 is bent upwardly so as to cooperate with the arm 117 of the locking plate 113 mounted on the lower side of the stationary deck 1. On rotation of the member 180 by the connecting member 181, the projection 183 rotates the locking plate 113 via its arm 117.

Thus the projection 116 clears the main shaft 44, thereby releasing the main shaft 44 and the sliding frame 4 from being locked in their advanced position, The sliding frame moves back under the influence of spring 102 thereby ejecting the cassette by cooperation between the engaging surface 47 on the sliding frame and the cassette. The portion of the member 180 including opening 1 84a for connecting the connecting member 181 and spring 182 is slightly curved upwardly so that when this portion is rotated in the clockwise direction by spring 187 it will engage the outer surface of lug 188 to act as a stop member.

When the rotary driving member 66 is rotated by the driving motor 120, the reel driving sprocket 65 is driven to wind tape.

The driven member 167 is coupled to the driving member 66 through the other friction disc 166 and thus the detection plate 73 is urged to rotate about point 71 in the direction of rotation of the driving sprocket 65 by cooperation with the upward projection 168 of the driven member 167. In addition, the eccentric cam 67 is provided for rotating the detecting plate 73 in the opposite direction of the rotation imparted thereto from the driven member 167. Thus normally the detecting plate 73 oscillates about the point 71 with the bias imparted by driven member 167 keeping the side 177 of the opening 172 in contact with the eccentric cam 67, which latter guides the oscillation of the plate 73. There is also provided the projection 68 which can drive the detection plate 73 in a direction at an angle transverse to its oscillatory motion about the point 71 that is generally radially towards the point 71 by cooperating with the shoulder 178. However during normal winding of the tape, the detection plate 73 will be rotated by the driven member 167 to keep the projection 68 from the shoulder 178, through the friction discs so long as the driven sprocket 65 continues to rotate. When the end of the tape is reached it stops. When the tape bulges outwardly at the pinch wheel 56, the rotation of the reel driving sprocket is also stopped. Accordingly, the driven member 167 is no longer urged in the direction of rotation of driving member 66 so that the driving power for driving the detection arm 73 in the same direction as the driving member 66 disappears. As a consequence, the rotation of only the driving member 66 is continued and the detection arm 73 is moved to and remains in the extreme position to which it is rotated about point 71 by the c

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

the end of the tape is reached it stops. When the tape bulges outwardly at the pinch wheel 56, the rotation of the reel driving sprocket is also stopped. Accordingly, the driven member 167 is no longer urged in the direction of rotation of driving member 66 so that the driving power for driving the detection arm 73 in the same direction as the driving member 66 disappears. As a consequence, the rotation of only the driving member 66 is continued and the detection arm 73 is moved to and remains in the extreme position to which it is rotated about point 71 by the cam 67 in the direction opposite to the direction of rotation of the driving member 66. When the rotation of the driving member 66 is continued under these conditions, the projection 68 of the cam 67 engages the shoulder 178 of the detection arm 73 and drives it in the direction transverse to its oscillatory motion imparted by the driven member 167 and the cam 67. Thus the unlocking arm is rotated counter clockwise as seen in Figure 8, and the switch releasing member 180 is rotated, via connecting rod 181, to mechanically stop the capstan and to switch off the motor. In the case of tangling of the tape, the reel driving sprocket 65 is rotated in the opposite direction by the removal of the tangled portion of the tape so that the driven member 167 will not act upon the detection arm 73 as in the normal rotation, thus mechanically stopping the driving motor.

As above described the plurality of pins

128 for engaging the latch member 186 are provided on the flywheel about the capstan thus it is possible for the latch member to accurately engage the flywheel for stopping the flywheel in response to stopping of the take up reel. More particularly, not only during the normal tape take up operation at the time of reproducing, but also during the high speed running operation, one of the pins 128 can accurately engage the latch member 186 thereby assuring automatic stopping of the tape recorder. For this reason, even when the locking device 140 for the high speed running is engaged, it is possible for the locking device to be released by the detection operation by cooperation of the portion 143 of the locking device 140 and the front edge 5a of the head plate 5. This enables the use of the locking device for much higher speed running than was possible with the prior art device. When the detection arm 73 is moved, the latch member 186 is held near the pins 128 of the flywheel and then positively moved by the connecting rod 181 whereby the latch member 186 instantly and accurately engages one of the pins 128. This prevents erroneous operation caused by manufacturing errors or slight movements.

The movement of the switch releasing member 180 operates a switch for starting or stopping the motor 120. When the flywheel begins to rotate, the latch member 186 is caused to disengage the pins 128 by rotation of the switch releasing member 180, with lug

188 of the latch member 186 co-operating with the portion of the member 180 having the opening 184a; the member 180 having been rotated by the locking plate 113 when the arm 116 engages the main shaft 44. Then the detection arm 73 and other members are released from the stop position whereby smooth starting of the tape can be assured.

The locking member 140 for the high speed running is released by the movement of the switch releasing member 180 via the head plate 5. During high speed running engagement of the inclined surface 152 with roller 132 maintains the head plate 5 away from the tape, though the plate is moved backwards with the sliding frame 4. On release of the sliding frame 4, the edge 5a of the head plate 5 contacts the bent-up portion 143 of the locking member 140 and releases it. As above described, not only abnormal conditions at the time of high speed running can be accurately detected but also the restarting of the high speed running can be made readily.

WHAT WE CLAIM IS: 1. A recording tape transport mechanism provided with an automatic stopping device comprising: a detection arm mechanically operated in response to stopping of rotation of a tape reel driving sprocket, a member connected to the detection arm through a connecting rod and a spring to be rotated according to the movement of the detection arm, a latch member pivotally connected to the said member to be moved thereby and provided with an engaging member at an end thereof, and a plurality of engageable members provided on a flywheel rotated by a driving motor to transmit rotation to the reel driving sprocket, one of the engageable members engaging the engaging member of the latch member to directly stop the rotation of the flywheel, when the latch member is moved in response to stopping of rotation of the reel driving sprocket.
2. A mechanism as claimed in claim 1 wherein the said member connected to the detection arm is a switch releasing member whereby the driving motor is switched off when the detection arm is mechanically operated in response to stopping of rotation of the reel driving sprocket.
3. A mechanism as claimed in claim 1 or claim 2 including a rotation transmission member connected to the reel driving sprocket for transmitting thereto drive from the driving motor, the rotation transmission member being provided with an eccentric

cam and a projection, a first driven member coupled to the rotation transmission member through a first friction member and connected to the reel driving sprocket, a second driven member coupled to the first driven member through a second friction member, the second driven member being provided with a projection, a detection plate connected to the said detection arm, the detection plate being provided with an opening for loosely accomodating the eccentric cam, one side of the opening being adapted to engage the eccentric cam to be urged thereby in a direction opposite to the direction of the rotation of the rotation transmission member and the other side of the opening being provided with a shoulder adapted to engage the projection on the rotation transmission member for driving the detection plate in a direction transverse to its motion imparted thereto by the cam, the detection plate being further provided with a slot for receiving the projection on the said second driven member to be urged thereby in the direction of rotation of the rotation transmission member.
4. A mechanism as claimed in claim 3 wherein the detection plate is provided with an arcuate guide opening having a centre of curvature at a pivot axis of the detection plate, and the detection arm is provided with a projection received in the arcuate guide opening.
5. A mechanism as claimed in claim 2 or either of claim 3 and claim 4 when appendant on claim 2 wherein the detection arm is provided with a connection member at a free end thereof, the connection member is provided with a circular opening and a slot, one end of the connecting rod is received in the slot and the other end is connected to the switch releasing member which is pivotally mounted and the circular opening and the switch releasing member being interconnected by the spring.
6. A mechanism as claimed in any preceding claim wherein a spring is connected between the latch member and the said member connected to the detection arm for urging the latch member to rotate.
7. A mechanism as claimed in any preceding claim including a tape transducer head mounting plate which is provided with a side wall spaced from a pinch roller thereby forming therebetween a space for accumulating the tape.
8. A mechanism as claimed in claim 7 wherein the pinch roller is rotatably mounted on a portion of a pinch roller supporting frame, a tape guide is mounted on the said intermediate portion for guiding the accumulated tape, and the tape guide is provided with a curved guide surface for guiding the tape toward the side wall.
9. A mechanism as claimed in any preceding claim for use with a tape cassette and including an elevating platform movable in a vertical direction with respect to a stationary deck of the mechanism. a sliding frame mounted with the elevating platform and which slides in a horizontal direction with respect to the deck, the sliding frame and the elevating platform being moved to their operating positions by the loading of a tape cassette, and a locking plate pivotally mounted on the deck for locking the sliding frame and elevating platform in their operating positions, and wherein the said member connected to the detection arm actuates the locking plate so as to release the locking condition of the sliding frame and elevating platform in response to the movement of the detection arm when the reel sprocket stops, thereby ejecting the loaded tape cassette by cooperation of an engaging surface on the sliding frame and the cassette.
10. A mechanism as claimed in claim 9, wherein the sliding frame is provided with a main shaft, the locking plate is provided with a projection for engaging the main shaft to lock the sliding frame and the elevating platform in their operating positions, and the said member connected to the detection arm for urging the latch member to rotate is provided with a projection arranged to engage another projection of the locking plate for releasing the engagement between the main shaft and the said projection for engaging the main shaft.
11. A mechanism as claimed in claim 9 or claim 10 wherein the sliding frame is provided with a switching member for operating a switch for connecting the driving motor to a source of electricity, and the driving motor is switched off when the sliding frame is moved to an inoperative position in response to the stopping of rotation of the reel driving sprocket.
12. A mechanism as claimed in claim 10, or claim 11 when appendant on claim 10 wherein a guide pin provided for the elevating platform is received in a vertical guide slot of the sliding frame and in an inclined guide slot in the stationary deck, and the main shaft is received by a guide member provided on the said elevating platform for guiding the vertical movement thereof.
13. A mechanism as claimed in claim 7 or any one of claims 8 to 12 when appendant thereto including a high speed running control member for establishing a high speed running condition of the tape, and a high speed running locking plate for locking the high speed running control member in its operating position, and wherein the high speed running locking plate is arranged to be operated by the end of the head mounting plate which is moved in response to the movement of the detection arm, thereby releasing the high speed running condition of the tape when the rotation of the reel driving sprocket is stopped.
14. A mechanism as claimed in claim 13, as appendant on claim 7 and claim 9 or on any of claims 10 to 12 when appendant on claim 7 and claim 9, including a motion transmission system for transmitting the rotation of the driving motor to the flywheel and the reel driving sprocket, the motion transmission system including a first intermediate rotary member for running a a tape at a normal speed, and a second intermediate rotary member for running the tape at a higher speed, an idler plate slidably mounted on the elevating platform for cooperating with the intermediate rotary members, the high speed running control member being arranged to operate the idler plate, an arm connected to the high speed running control member through spring means for operating the idler plate, and a vertical cam provided on the arm for maintaining engagement between the arm and the idler plate irrespective of the vertical movement of the elevating platform.
15. A mechanism as claimed in claim 14 including a cassette ejecting member for releasing the elevating platform from its operating position, and a projection mounted on the ejecting member for cooperating with an arm provided on the high speed running locking plate.
16. A mechanism as claimed in claim 15 including a guide frame mounted on the stationary deck for receiving a tape cassette and for slidably supporting the ejecting member, an ejection link mounted on the stationary deck to be engaged by the ejecting member for releasing the sliding frame and ejecting a loaded cassette, and the high speed running locking member being pivotally mounted on the stationary deck to be engaged by the ejecting member.
17. A mechanism as claimed in claim 9 or any one of the claims 10 to 16 when appendant to claim 9 including a leaf spring secured to the stationary deck and wherein the elevating platform is provided with means for receiving a free end of the leaf spring when the elevating platform is raised to its operative position.
18. A mechanism as claimed in claim 17 wherein the leaf spring takes the form of a letter L with its free leg projected into the path of movement of the elevating platform and the means for receiving the free end of the leaf spring comprises a notch formed at one edge of the elevating platform.
19. A mechanism as claimed in claim 8 and claim 10 or any one of claims 11 to 18 when appendant to claim 8 and claim 10 wherein the pinch roller supporting frame and the head mounting plate are pivotally mounted on the sliding frame by the main pivot shaft, and including spring means for urging a tape transducer head supported by the head mounting plate and the pinch roller supported by the pinch roller supporting plate against the tape, and means for positioning the pinch roller supporting frame and the head mounting plate, the movement of the positioning means is regulated by a cam of the sliding frame and a slot of the stationary deck, and wherein the head and the pinch roller are released from the engagement with the tape when the sliding frame is moved in response to the movement of the detection arm when the reel driving sprocket stops.
20. A mechanism as claimed in claim 20 wherein the head mounting plate is provided with a cam slot and the pinch roller supporting frame is formed with a cam surface and the said positioning means engages the said cam slot and the said cam surface for operating the pinch roller supporting plate and the head mounting plate.
21. A mechanism as claimed in claim 19 or claim 20 wherein the pinch roller supporting frame comprises an arm extending from one side thereof for engaging an upright side wall of the head mounting plate, and the said spring means is connected between the arm and the said positioning means.
22. A mechanism as claimed in claim 3 or any one of claims 4 to 21 when appendant to claim 3 including spring means for coupling the rotation transmission member with the second driven member through the friction members.
23. A mechanism as claimed in claim 3 or any one of claims 4 to 22 when appendant to claim 3 including a securing member for securely coupling the motion transmission member to the second driven member through the second friction disc.
24. A recording tape transport mechanism substantially as hereinbefore described with reference to the accompanying drawings.