GB2231705A - A sequence control mechanism employing the gear mechanism - Google Patents
A sequence control mechanism employing the gear mechanism Download PDFInfo
- Publication number
- GB2231705A GB2231705A GB9005376A GB9005376A GB2231705A GB 2231705 A GB2231705 A GB 2231705A GB 9005376 A GB9005376 A GB 9005376A GB 9005376 A GB9005376 A GB 9005376A GB 2231705 A GB2231705 A GB 2231705A
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- United Kingdom
- Prior art keywords
- gear
- toothless
- partly
- transmitting
- transmitting gear
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B15/00—Driving, starting or stopping record carriers of filamentary or web form; Driving both such record carriers and heads; Guiding such record carriers or containers therefor; Control thereof; Control of operating function
- G11B15/18—Driving; Starting; Stopping; Arrangements for control or regulation thereof
- G11B15/44—Speed-changing arrangements; Reversing arrangements; Drive transfer means therefor
- G11B15/442—Control thereof
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B15/00—Driving, starting or stopping record carriers of filamentary or web form; Driving both such record carriers and heads; Guiding such record carriers or containers therefor; Control thereof; Control of operating function
- G11B15/18—Driving; Starting; Stopping; Arrangements for control or regulation thereof
- G11B15/1883—Driving; Starting; Stopping; Arrangements for control or regulation thereof for record carriers inside containers
Abstract
A sequence control mechanism has a drive gear 18 and an arm 19 pivotally mounted on the same shaft 5. A transmitting gear 20 is mounted on said pivot arm and in engagement with said drive gear. At least one partly toothless gear 23, 24 or 25 having a toothed portion is so positioned in the pivotal path of the transmitting gear that engagement of the toothed portion with the transmitting gear stops the transmitting gear idling. A first mechanism e.g. a head plate (9) is driven by the partly-toothless gear and acts to return the partly-toothless gear to a position in which said toothed portions are in the path of said transmitting gear. A second mechanism e.g. a tape take up reel 3 or supply reel 4 which, when said transmitting gear has passed by said toothless portions of said partly-toothless gear, engages with said transmitting gear and is driven thereby. This mechanism makes it possible to perform sequence control and switching of the rotating direction without use of the clutch mechanism or the electromagnets used in the prior art. <IMAGE>
Description
A SEQUENCE CONTROL MECHANISM EMPLOYING GEAR MECHANISM
Field of the Invention
The present invention relates to a sequence control mechanism employing gears. An example of an application is in an operation-mode switching device in a tape recorder.
Background of the Invention
Conventionally, a so called sequence control mechanism has first and second actuating portions, in which the rotating force of the drive rotator, such as a gear, driven by a motor is transmitted to the first actuating portion so that the first actuating portion can perform the predetermined operations, and, when said operations have been finished, said rotating force of the drive rotator is transmitted to the second actuating portion so that the second actuating portion can perform the predetermined operations.Such a sequence control mechanism, generally, is provided with clutch mechanism on the rotation transmitting paths of the first and second actuating portions, whereby the clutch mechanism on the first actuating portion side is connected and the clutch mechanism on the second actuating portion side is disconnected so that said clutch mechanism on the first actuating portion side is operated. When the predetermined operation of said first actuating portion has been finished, the clutch mechanism on the first actuating portion side is disconnected and at this time the clutch mechanism on the second actuating portion side is connected so that the second actuating portion may perform the predetermined operation.
In such a conventional sequence control mechanism, there have been problems. Since it requires a clutch mechanism on the rotation transmitting path of each actuating portion, and a control mechanism for controlling the timing when each of these clutch mechanisms is connected and disconnected, the construction thereof becomes complicated. Also the rotation transmitting path of each of the actuating portions becomes complicated.
Summary of the Invention
In accordance with the invention there is provided a sequence control mechanism, comprising; a drive gear driven in use by a motor; an arm pivotally mounted on the same shaft as the drive gear; a transmitting gear which is supported by a shaft mounted on said pivot arm and in engagement with said drive gear; a partly toothless gear having a toothed portion so positioned in the pivotal path of the transmitting gear that engagement of the toothed portion with the transmitting gear stops the transmitting gear idling, the toothless portion permitting the transmitting gear to idle; a first mechanism driven by the partly-toothless gear and which acts to return the partly-toothless gear to a position in which said toothed portions are in the path of said transmitting gear; and a second mechanism which, when said transmitting gear has passed by said toothless portion of said partly-toothless gear, engages with said transmitting gear so that it is driven by said drive gear.
In a preferred embodiment, the first mechanism comprises a cam mounted on either the partly-toothless gear or the first actuating mechanism and a cam follower mounted on the other.
Furthermore, it is preferable to make said motor rotatable forwardly and reversely.
If the drive gear is driven to rotate in one direction by the motor, the pivot arm pivots in the one direction to engage the toothed portions of the partly-toothless gear, so that the idling operation is blocked, and the partly-toothless gear rotates in the one direction. By the rotation in the one direction of said partly-toothless gear, the first mechanism is operated. As the predetermined operation of this first mechanism has been completed, said toothless portion of the partly-toothless gear is presented. The transmitting gear passes through the toothless portion, the pivot arm pivots in the one direction so that the transmitting gear engages the second mechanism, thereby allowing the second mechanism to perform the predetermined operation.
Brief Description of the Drawings
These and other objects, features and advantages of the invention will become more apparent from the following description of a preferred embodiment of the present invention given by way of example with reference to the accompanying drawings, in which :
Fig. 1 is a plan view illustrating schematically the chassis
of a tape recorder and/or player which is provided with a
sequence control mechanism embodying the present invention:
Fig. 2 is a schematic plan view showing a part of the
sequence control mechanism of Fig 1.
Figs. 3 to 15 are views of assistance in explaining the
operation of the sequence control mechanism of Fig 1.
Fig. 16 is a view for explaining operation of the pivotal
arm of the sequence control mechanism; and
Fig. 17 illustrates the relationship between the reversing
timing of the rotation direction of a motor and the position
of a magnetic recording and reproducing head in each
operating state of said sequence control mechanism.
Description of the Preferred Embodiment
An embodiment of the present invention will now be described in detail with reference to the drawings.
Fig. 1 is a schematic plan view of the chassis of a tape recorder and/or player which is provided with a sequence control mechanism embodying the present invention, and Fig 2 is a schematic plan view showing a part of the sequence control mechanism of Fig 1.
In these two drawings, Reference numeral 1 indicates a base plate, which is provided with a motor 2 rotatable forwardly and in reverse, a take-up reel 3, a supply reel 4, and a capstan 5 respectively on the predetermined positions thereof. A drive shaft 2a of said motor 2 projects through to the lower or reverse side of the base plate 1. A motor pulley 6 is fixed to the end thereof. A lower end of a capstan 5 projects through to the lower side of said base plate 1. On the end thereof a flywheel 7 is fixed. An endless belt 8 extends around said flywheel 7 and said motor pulley 6. The take-up reel 3 on the left of the drawing is constituted in such a way that on a reel gear 3a a reel rest or spindle 3b is mounted to rotate with said reel gear 3a.The supply reel 14 also is constituted in such a way that on a reel gear 4a a reel rest or spindle 4b is mounted to rotate with said reel gear 3a. On the upper side of the base plate 1, a head mounting plate 9 is mounted for movement and in the direction of arrows A and B. To the upper side of said head mounting plate 9, a magnetic recording and reproducing head 10 and a magnetic erasing head 11 are attached. Said head mounting plate 9 is biased in the direction of arrow B (stop position direction) by a head return spring 12. On the upper side or front of the base plate 1, one end of a pinch roller arm 13 is mounted on a shaft 14 for pivotal movement in the direction of arrows C and D. On the other end of said pinch roller arm 13, a pinch roller 15 is rotatably mounted on a shaft 16. The other end of the pinch roller arm 13 is connected through a rod-like pinch roller spring 17 to the head mounting plate 9. As said head mounting plate 9 is moved in the direction of arrow A or B, the pinch roller arm 13 is rotated in the direction of arrows C or D through said pinch roller spring 17. A tape in the cassette (not shown) is thus pinched between the pinch roller 15 and the capstan 5. In Fig. 1, the pinch roller arm 13 is biased by the pinch roller spring 17 in the direction where the pinch roller 15 is separated from the capstan 5 (in the direction of arrow D).
On the flywheel 7 a drive gear 18 is mounted to rotate with said flywheel 7. Between this drive gear 18 and the base plate 1, one end of a pivot arm 19 is pivotally mounted on the capstan 5 coaxial with said drive gear 18. On the other end of said pivot arm 19 a transmitting gear 20, which is engaged with the drive gear 18, is rotatably mounted on a shaft 21.
In Fig. 2, when the pivot arm 19 reaches the clockwise rotation limit position, the transmitting gear 20 engages the reel gear 3a of the take-up reel 3 to rotate the take-up reel 3. Also, when the pivot arm 19 reaches the counterclockwise rotation limit position, the transmitting gear 20 engages the reel gear 4a of the supply reel 4, to rotate the supply reel 4. Accordingly, the take-up reel 3 and the supply reel 4. are embodiments of a second mechanism, eg actuating mechanism, which, when said transmitting gear 20 has passed by the toothless portions 23b and 24b of first and second partly-toothless gears 23 and 24, is engaged with said transmitting gear 20 so that it is driven by the drive gear 18. Stopping clockwise rotation of the pivot arm 19 is performed by a face 19a of said pivot arm 19 which engages one end 22a of a stop 22 of the base plate 1.Stopping counterclockwise rotation of the pivot arm 19 is performed by a face 19B of said pivot arm 19 which engages the other end 22b of the stop 22 of the base plate 1.
On the lower side of the base plate 1 first, second and third partly-toothless gears 23, 24 and 25 are mounted to rotate about shafts 26, 27 and 28 respectively. Third partly-toothless gear 25 is disposed between the first partly-toothless gear 23 and the second partly-toothless year 24. The first, second and third 23, 24 and 25 partly toothless gears have toothed portions 23a, 24a and 25a and toothless portions 23b, 24b and 25b on outer peripheral sides, respectively. The partly toothless gears 23, 24, and 25 are so positioned that when the transmitting gear 20 engages the toothed portion 23a, 24a and 25a, idling of said transmitting gear 20 is prevented. The toothless portion 23b, 24b and 25b permit idling of the transmitting gear 20.
On the first and second partly-toothless gears 23 and 24, cams 29 and 30 are mounted respectively. The cam 29 of the first partlytoothless gear 23 comprises a first arched portion 29a being at a constant distance from a rotating centre of shaft 26, a second arched portion 29b of which one end is continuously extended from the one end of said first arched portion 29a and to which the distances from the rotating centre of shaft 26 become gradually less from the one end thereof toward the other end thereof, a first inclined portion 29C of which one end is continuously extended from the other end of said second arched portion 29b and of which the other end is inclined toward the rotating centre of shaft 26, a second inclined portion 29d of which an end is continuously extended from the other end of said first inclined portion 29c and of which the other end is inclined inversely toward the rotating centre shaft, and a third inclined portion 29e which is connected between said other end of said second inclined portion 29d and the other end of said first arched portion 29a.The cam 30 of the second partly-toothless gear 24 comprises a first arched portion 30a being at a constant distance from a rotating centre of shaft 27, a second arched portion 30b of which one end is continuously extended from the one end of said first arched portion 30a and to which the distances from the rotating centre of shaft 27 become gradually less from the one end thereof toward the other end thereof, a first inclined portion 30b of which one end is continuously extended from the other end of said second arched portion 30b and of which the other end side is inclined toward the rotating centre of shaft 27, a second inclined portion 30d of which one end is continuously extended from the other end of said first inclined portion 30c and of which the other end side is inclined toward the rotating centre of shaft 27, and a third inclined portion 30e which is connected between said other end of said second inclined portion 30d and the other end of said first arched portion 30a.
In the cams 29 and 30 of the first and second partly-toothless gears 23 and 24, cam followers in the form of pins 31 and 32 mounted on the lower surface 9 respectively project through elongate holes 33 and 34. By operation of the cams 29 and 30, depending on the direction of rotation of the first and second partly-toothless gears 23 and 24, the head mounting plate 9 is moved in the direction of arrow A or B through the cam follower pins 31 and 32. The head mounting plate 9 is biased in the direction of arrow B by the head return spring 12. The force of the spring 12 is transmitted through the cam follower pins 31 and 32 to the first and second partly-toothless gears 23 and 24.
Accordingly, the head mounting plate 9 and the head return spring 12 embody a first mechanism, eg actuating mechanism, which acts to return the partly toothless gear to a position in which the toothed portions 23a and 24a are in the path of the transmitting gear 20. On the upper side of the third partly-toothless gear 25 is mounted a first cam 35 and on the lower side there is mounted a second cam 36, respectively.The first cam 35 comprises an arched portion 35a being at a constant distance from a rotating centre of shaft 28, a first inclined portion 35b of which one end is continuously extended from the one end of said arched portion 35a and the other end of which is inclined toward the rotating centre of shaft 28, a second inclined portion 35c of which at one end is connected continuously with the other end of said second inclined portion 35b and the other end of which side is inclined inversely toward the rotating centre of shaft 28, a third inclined portion 35d one end of which is connected continuously with the said second inclined portion 35c and the other end of which is inclined toward the rotating centre of shaft 28 in such a manner that it has the relationship of line symmetry to the second inclined portion 35c, and a fourth inclined portion 35e which is connected between the other end of the third inclined portion 35d and the other end of the arched portion 35a and which has the relationship of line symmetry to the first inclined portion 35b. On said first cam 35, a V-shaped and curved portion 37a, which is one end of a brake spring 37 in the form of a rod spring, is in sliding engagement therewith. Said brake spring 37 is disposed in such a manner that a ring-shaped portion 37b and the other end 37c are locked in a spring locking member (not shown) of the base plate 1. By the brake spring 37, the rotating position of the third partly-toothless gear 25 is restricted.
The second cam 36 of the third partly-toothless gear 25 has an arched portion which is concentric with the rotating centre of shaft 28 thereof, and a substantially triangular expansion portion 36b projecting at the one portion of the outer periphery thereof. The expansion portion 36b of the second cam 36 pushes a movable contact 38a of a motor stop switch 38, depending on the rotational position of the third partly-toothless 25, to contact the movable contact 38a with a fixed contact 38b, thereby turning the motor stop switch 38 ON. This motor stop switch 38 is attached to the lower surface of the base plate 1. An electrical circuit is arranged so that, the motor stops only when the motor stop switch 38 is turned on and when at this time a stop operation switch (not shown) is operated.Accordingly, when the stop operation switch is not operated even though the motor stop switch 38 is turned on the motor 2 is not stopped.
Now, the operation of the tape recorder having the construction described above will be explained with reference to Figs 1 through 17 as follows :
Firstly, the explanation with reference to the reproduction
or play operation mode thereof will be made.
If, when the tape recorder is in the stop state shown in Figs 1 and 2, a switch for reproducing operation (not shown) is operated, then the motor 2 is rotated at a constant speed clockwise (forward) in the drawings on the basis of the operating signal from said switch. By the rotation of this motor 2, the flywheel 7, the drive gear 18 and the capstan 5 are rotated clockwise together through the motor pulley 6 and the endless belt 8. The transmitting gear 20 is also rotated counterclockwise, and the pivot arm 19 is urged to pivot clockwise about the capstan 5.Rowever, the tooth top of the transmitting gear 20 engages the tooth bottom of the toothed portion 25a of the third partly-toothless gear 25 as shown in
Fig. 16, before the centre of the transmitting gear 20 reaches the line connecting the centre of drive gear 18 and the centre of the third partly-toothless gear 25, thereby stopping the pivoting clockwise of the pivot arm 19 and idling of the transmitting gear 20. In this state, the third partly-toothless gear 25 is rotated clockwise by a predetermined angle through the transmitting gear 20 driven by the drive gear 18. By this rotation of the third partly-toothless gear 25, since the expansion portion 36b of the second cam 36 is separated from the movable contact 38a of the motor stop switch 38, the movable contact 38a is separated from the fixed contact 38a, so that the motor stop switch 38 is turned off.As by the rotation of the third partly-toothless gear 25, the toothless portion 25b thereof reaches the transmitting gear 20, this transmitting gear 20 is separated from the third partlytoothless gear 25, whereby the pivot arm 19 is rotated clockwise.
At this time, that is, when the third partly-toothless gear 25 reaches a position in which rotation terminates, this third partly-toothless gear 25 is reversely-rotated slightly counterclockwise by sliding contact between the curved portion 37a of the brake spring 37 with the second inclined portion 35c of the first cam 35, so that said curved portion 37a is stably stopped in the state in which a first curved recess 35f between the first inclined portion 35b and the second inclined portion 35c engages the spring 37, see Fig. 3. When the pivot 19 has been reversely rotated counterclockwise, the third partlytoothless gear 25 can thus be smoothly and surely engaged with the toothed portion 25a of the third partly-toothless gear 25.
The transmitting gear 20 leaves the third partly-toothless gear 25 to engage the toothed portion 23a of the first partlytoothless gear 23 and the pivot arm 19 is urged to pivotably rotate clockwise. However, the tooth top of the transmitting gear 20 engages the tooth bottom of the toothed portion 23a of the first partly-toothless gear 23, before the centre of the transmitting gear 20 reaches a line connecting the centre of the drive gear 18 and the centre of first partly-toothless gear 23, thereby stopping the pivoting clockwise of the pivot arm 19 (in the state of Fig. 3). In this state, the first partly-toothless gear 23 is rotated clockwise by a predetermined angle through the transmitting gear 20 driven by the drive gear 18.With this rotation of the first partly-toothless gear 23, one cam follower pin 31, which has been locked by this time in the first curved recess 29f between the first arched portion 29a and the third inclined portion 29e of the cam 29, is slidably contacted with first and second arched portions 29a and 29b and first inclined portion 29c sequently, so that the head mounting plate 9 is moved in the direction of arrow A against the biassing force of the head return spring 12 through the cam follower pin 31. At the termination of said movement, the toothless portion 23a of the first partly-toothless gear 23 is reached at the transmitting gear 20 and therewith one cam follower pin 31 is slidably contacted with the first inclined portion 29c of the cam 29 (in the state of Fig. 4).The cam follower pin 31, is biassed in the direction of arrow B though the head mounting plate 9 by the head return spring 12. The pin 31 is in sliding engagement with the first inclined portion 29c of the cam 29. Therefore, the first partly-toothless gear 23 is rotated counterclockwise slightly so that the cam follower pin 31 is stably stopped in the state engaged with a second curved recess 29g between the second arch portion 29b and the first inclined portion 29c of the cam 29.
When the pivot arm 19 rotates counterclockwise, the transmitting gear 20 can be smoothly engaged with the toothed portion 23a of the first partly-toothless gear 23. As the first partly toothless gear 23 is slightly rotated counterclockwise to engage the cam follower pin 31 with the second curved portion 29g of the cam 29, the head mounting plate 9 is slightly returned in the direction of arrow B from the state of Fig. 4 by the biasing force of the head return spring 12, thereby keeping stably in the reproduction operation position.
As the head mounting plate 9 reaches the reproducing operation position the tape is pinched between the pinch roller 15 and the capstan 5 and the magnetic recording/reproduction head 10 engages the tape. As the toothless portion 23b of the first partlytoothless gear 23 reaches transmitting gear 20, this transmitting gear 20 leaves the gear 23 and the pivot arm 19 rotates clockwise so that the surface 19a thereof contacts one end 22a of the stopper member 22, thereby restricting the maximum clockwisepivoting position thereof. Consequently, the transmitting gear 20 is engaged with the reel gear 3a of the take-up reel 3 and this take-up reel 3 is rotated clockwise, so that the tape is shifted at a low speed from the supply reel 4 to the take-up reel 3, thereby performing the reproducing operation (in the state of
Fig. 5). The maximum clockwise-pivoting position of the pivot arm 19 is arranged in such a position that, the reel gear 3a of the take-up reel 3, provided with a slip mechanism (not shown), is engaged with the transmitting gear 20 a pitch circle to a pitch circle. When the head mounting plate 9 has been moved at the position of the reproducing operation, from a position detecting switch (not shown) for detecting the position of the head mounting plate 9 a signal is output representing that the head mounting plate 9 is in the position of the reproducing operation.
Next, the fast forward operation will be explained.
In the stop state as shown in Figs. 1 and 2, if a switch for fast forward operation mode (not shown) is operated, by the operation signal the motor 2 is rotated clockwise, and the operations from the next operation till the transmitting gear 20 is engaged with the reel gear 3a of the take-up reel 3 are the same as the aforementioned reproducing operation. However, if the signal produced by the operation of the fast forward operation switch and the signal from the position detecting switch representing that the head mounting plate 9 is in the position of reproducing operation are detected, by these signals an inverting circuit (not shown) for the motor 2 is operated so that the motor 2 is rotated counterclockwise (in the reverse direction).By this rotation, the pivot arm 19 also is pivoted counterclockwise, the transmitting gear 20 rotating clockwise engages the toothed portion 23a of the first partly-toothless gear 23 and the pivot arm 19 is urged to pivot counterclockwise. However, the tooth top of the transmitting gear 20 engages the tooth bottom of the toothed portion 23a of the first pPrtly-toothless gear 23, before the centre of the transmitting gear 20 reaches the line connecting the centre of the drive gear 18 and the centre of first partly-toothless gear 23, thereby stopping the pivoting counterclockwise of the pivot arm 19 (in the state of Fig. 6).
In this state, the first partly-toothless gear 23 is rotated counterclockwise through the transmitting gear 20 driven by the drive gear 18. Since, by this rotation of the first partlytoothless gear 23, the one cam follower pin 31 is in sliding engagement with the second arched portion 29b of the cam 29, the head mounting plate 9 is moved in the direction of arrow B by the biassing force of the head return spring 12. When the one cam follower pin 31 is locked in a third curved recess 29h between the second arched portion 29b and the first arched portion 29a of the cam 29, the head mounting plate 9 reaches the initial position, so that the pinch roller 15 is off the capstan 5 and the magnetic recording/reproducing head 10 is off the tape (in the state of Fig. 7). As the head mounting plate 9 is returned to the stop position, the signal from the position detecting switch is not generated.Since, by this signal generating stop, the input of a inversion instruction signal to said motor inverting circuit is stopped, the motor 2 is again rotated clockwise and the pivot arm 19 also is rotated clockwise so that the transmitting gear 20 is engaged with the reel gear 3a of the take-up reel 3, thereby causing the take-up reel 3 to rotate clockwise. Thus, the tape is shifted at a high speed from the supply reel 4 side to the take-up reel 3 side, whereby the operation for fast forward mode is performed (in the state of
Fig. 8).
Next, a high speed erasing operation will be explained.
In the stop state of Figs. 1 and 2, if a switch for high speed operation (not shown) is operated, by the operating signal the motor inverting circuit is actuated so that the motor 2 is rotated counterclockwise at a constant speed. By the rotation of the motor 2, the flywheel 7, the drive gear 18 and the capstan 5 are rotated together counterclockwise, through the motor pulley 6 and the endless belt 8, and the transmitting gear 20 is rotated clockwise. Also the pivot arm 19 is urged to rotate counterclockwise about the capstan 5. At this time, since the transmitting gear 20 is departed from the third partly-toothless gear 25, the pivot arm 19 is rotated counterclockwise. The transmitting gear 20 departed from said third partly-toothless gear 25 engages the toothed portion 24a of the second partlytoothless gear 24 and the pivot arm 19 is urged to pivot counterclockwise.However, the tooth top of the transmitting gear 20 is engages the tooth bottom of the toothed portion 24a of the second partly-toothless gear 24, before the centre of the transmitting gear 20 reaches a line connecting the centre of the drive gear 18 and the centre of second partly-toothless gear 24, thereby stopping the pivoting counterclockwise of the pivot arm 19 (in the state of Fig. 9). In this state, the second partlytoothless gear 24 is rotated counterclockwise by a predetermined angle through the transmitting gear 20 driven by the drive gear 18.With this rotation of the second partly toothless gear 24, the other cam follower pin 32, which has been locked by this time in the first curved recess 30f between the first arched portion 30a and the second inclined portion 30b of the cam 30, is slidingly engaged the second arched portion 30b and the first inclined portion 30c of the cam 30, so that the head mounting plate 9 is moved from the stop state in the direction of arrow A against the biassing force of the head return spring 12 through the cam follower pin 32. At the termination of said movement, the toothless portion 24a of the second partly-toothless gear 24 reaches the transmitting gear 20 and therewith the other cam follower pin 32 is in sliding contact with the first inclined portion 30c of the cam 30 on the first partly-toothless gear 23 (in the state of Fig. 10).The other cam follower pin 32, is biassed in the direction of arrow B through the head mounting plate 9 by the head return spring 12 at the termination of movement in the arrow A direction of the head mounting plate 9 in
Fig. 10. The other cam follower pin 32 is sliding engagement with the first inclined portion 30c of the cam 30 of the second partly-toothless gear 24, so that said second partly toothless gear 24 is rotated slightly clockwise (reversely). The cam follower pin 32 is thus stably stopped in the state engaged with a second curved recess 30g between the second arched portion 30b and the first inclined portion 30c of the cam 30. Thus, when the pivot arm 19 has been reversely rotated clockwise, the transmitting gear 20 can be smoothly engaged with the toothed portion 24a of the second partly-toothless gear 24.As the second partly-toothless gear 24 is rotated slightly clockwise (reversely) to engage the other cam follower pin 32 with the first curved portion 30f of the cam 30, the head mounting plate 9 is returned slightly in the direction of arrow B from the state of Fig. 10 by the biassing force of the head return spring 12, thereby keeping stably in the erasing operation position. The amount of movement of the head mounting plate from the stop position to the erasing position is slightly smaller than that from the stop position to the reproducing operation position.
Consequently, when the head mounting plate 9 is in the position of the erasing operation, the pinch roller 15 is slightly spaced from the capstan 5 and at this time the magnetic recording/reproducing head 10 is slightly off the tape. The magnetic erasing head 11, however, is in contact with the tape (in the state of Fig. 10). If the toothless portion 24b of the second partly-toothless gear 24 reaches the transmitting gear 20, this transmitting gear 20 leaves the second partly-toothless gear 24. Due to this, the pivot arm 19 rotates counterclockwise so that the other end 19b thereof is in contact with the other end 22b of the stop 22 and the maximum position counterclockwise is restricted. Thus, the transmitting gear 20 is engaged with the reel gear 4a of the supply reel 4 so that the supply reel 4 rotates counterclockwise.Accordingly, the erasing operation is performed in which, with the tape being run at a high speed from the take-up reel 4 side to the supply reel 4 side, the recorded contents in the tape are erased (in the state of Fig. 11).
Now, the explanation is made of the rewinding operation mode.
In the stop state as shown in Figs. 1 and 2, if a switch for rewinding operation mode (not shown) is operated, by the operation signal the motor 2 is rotated counterclockwise, and the operations from the next operation till the transmitting gear 20 is engaged with the reel gear 41 of the supply reel 4 are the same as the aforementioned fast forward operation. However, if the signal produced by the operation of the rewinding operation switch and the signal from the position detecting switch representing that the head mounting plate 9 is in the position of the high speed erasing operation are detected, by said detected signal the inverting instruction signal is not input to the inverting circuit of the motor 2 so that the motor 2 is rotated clockwise.By this rotation, the pivot arm 19 is also pivoted clockwise, the transmitting gear 20 is engaged with the toothed portion 24a of the second partly-toothless gear 24 and the pivot arm 19 is urged to pivot clockwise. However, the tooth top of the transmitting gear 20 engages the tooth bottom of the tooth portion 24a of the second partly-toothless gear 24, before the centre of the transmitting gear 20 reaches a line connecting between the centre of the drive gear 18 and the centre of second partly-toothless gear 24, thereby stopping the pivoting clockwise of the pivot arm 19 (in the state of Fig. 12). In this state, the second partly-toothless gear 24 is rotated clockwise through the transmitting gear 20 driven by the drive gear 18.Since, by this rotation of the second partly-toothless gear 24, the other cam follower pin 32 is slidably engages the second arched portion 30b of the cam 30, the head mounting plate 9 is moved in the direction of arrow B by the force of the head return spring 12.
When the other cam follower pin 32 is locked in a first curved recess 30f between the second arched portion 30b and the first arched portion 30a of the cam 50, the head mounting plate 9 reaches the initial position, so that the pinch roller 15 is off the capstan 5 and the magnetic recording/reproducing head 10 and the magnetic erasing head 11 are off the tape (in the state of
Fig. 13). As the head mounting plate 9 is returned to the stop position, said motor inverting circuit is operated by the signal output from the position detecting switch so that the motor 2 is rotated counterclockwise. With this rotation, the pivot arm 19 is also rotated counterclockwise and the transmitting gear 20 rotating clockwise is engaged with the reel gear 4a of the supply reel 4, thereby causing the supply reel 4 to rotate counterclockwise.Thus, the tape is shifted at a high speed from the take-up reel 3 side to the supply reel 4 side, whereby the rewinding operation is performed (in the state of Fig. 14).
Lastly, description will be made of a mode switching operation from the reproducing operation state to the stop state.
In the reproducing operation mode as shown in Fig. 5, if the switch for stop operation (not shown) is operated, by this operation signal the motor inverting circuit is actuated so that the motor 2 is rotated counterclockwise. With this rotation of the motor 2, the pivot arm 19 is pivoted counterclockwise, so that the transmitting gear 20 is engaged with the toothed portion 23a of the first partly-toothless gear 25. Then, this first partly-toothless gear 23 is rotated counterclockwise.After the operations of the sates represented in Figs. 6 and 7 have been performed the transmitting gear 20 is engaged with the toothed portion 25a of the third partly-toothless gear 25 as shown in
Fig. 15. consequently, the third partly-toothless gear 25 is rotated counterclockwise so that the protruded portion 36b of the second cam gear 36 presses down the movable contact segment 39a of the motor stopping switch 38, thereby causing the movable contact segment 38a to contact the fixed contact segment 38b.
Therefore, the motor stopping switch 38 is turned on. As described above, since the stop operation switch has already been operated, both of the operation signal from the stop operation switch and the ON signal from the motor stopping switch 38 are established. Accordingly, the supply voltage to the motor 2 is interrupted, so that the motor 2 is stopped and the tape recorder is in the stop state shown in Fig. 2.
Fig. 17 represents the relationship of the positions of the magnetic recording/reproducing head in each of the operating states and the reversing timing of the rotation direction of the motor 2 in each of the operation switching states. The broken lines represent that the motor 2 is stopped, the solid lines above the broken lines represent that the motor 2 rotates forward (clockwise) on the drawing). The solid lines below the broken lines represent that the motor 2 rotates reversely (counterclockwise in the drawing).
While the preferred embodiment of the invention is applied to a tape recorder, it is to be understood that the invention is not limited thereto, but is capable of having application to various uses, for example, a motor drive unit for actuating an automatic film winding and a shutter set of a camera, an actuating mechanism which in a video tape recorder presses contactably a tape to a capstan after a tape loading has been completed, or an actuating mechanism which controls a plurality of electromagnets to actuate sequently a plurality of actuating portions, etc.
Claims (4)
1. A seguence control mechanism, comprising; a drive gear
driven in use by a motor; an arm pivotally mounted on the
same shaft as the drive gear; a transmitting gear which is
supported by a shaft mounted on said pivot arm and in
engagement with said drive gear; a partly toothless gear
having a toothed portion so positioned in the pivotal path
of the transmitting gear that engagement of the toothed
portion with the transmitting gear stops the transmitting
gear idling, the toothless portion permitting the
transmitting gear to idle; a first mechanism driven by the
partly-toothless gear and which acts to return the partly
toothless gear to a position in which said toothed portions
are in the path of said transmitting gear; and a second
mechanism which, when said transmitting gear has passed by
said toothless portions of said partly-toothless gear,
engages with said transmitting gear so that it is driven by
said drive gear.
2. A sequence control mechanism according to Claim 1, wherein
the first mechanism comprises a cam mounted on either the
partly-toothless gear or the first mechanism and a cam
follower mounted on the other.
3. A sequence control mechanism according to Claim 1, wherein
said motor is rotatable both forwardly and in reverse.
4. A sequence control mechanism substantially as hereinbefore
described with reference to the drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1058958A JPH02239453A (en) | 1989-03-10 | 1989-03-10 | Sequence control mechanism using gear mechanism |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9005376D0 GB9005376D0 (en) | 1990-05-02 |
| GB2231705A true GB2231705A (en) | 1990-11-21 |
| GB2231705B GB2231705B (en) | 1993-08-18 |
Family
ID=13099351
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9005376A Expired - Fee Related GB2231705B (en) | 1989-03-10 | 1990-03-09 | A sequence control mechanism employing gear mechanism |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JPH02239453A (en) |
| CN (1) | CN2061323U (en) |
| GB (1) | GB2231705B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2557213B (en) * | 2016-11-30 | 2019-12-04 | Innovative Tech Ltd | A banknote storage unit |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1603180A (en) * | 1977-05-13 | 1981-11-18 | Hitachi Ltd | Cassette tape recorder having mechanical power-transmitting system |
| GB2210494A (en) * | 1987-09-24 | 1989-06-07 | Sankyo Seiki Seisakusho Kk | Mode changer for a tape recorder |
-
1989
- 1989-03-10 JP JP1058958A patent/JPH02239453A/en active Pending
-
1990
- 1990-01-09 CN CN90200065U patent/CN2061323U/en not_active Withdrawn
- 1990-03-09 GB GB9005376A patent/GB2231705B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1603180A (en) * | 1977-05-13 | 1981-11-18 | Hitachi Ltd | Cassette tape recorder having mechanical power-transmitting system |
| GB2210494A (en) * | 1987-09-24 | 1989-06-07 | Sankyo Seiki Seisakusho Kk | Mode changer for a tape recorder |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02239453A (en) | 1990-09-21 |
| GB9005376D0 (en) | 1990-05-02 |
| CN2061323U (en) | 1990-08-29 |
| GB2231705B (en) | 1993-08-18 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19940309 |