JPH0366742B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pinch roller pressing mechanism for a video tape recorder. The cassette type video tape recorder does not have a loading mechanism for pulling out the tape from the cassette and loading the tape on a guide cylinder.
The pinch roller for running the loaded tape at a constant speed is located in the cassette notch in the unloading state, is displaced to a position facing the capstan in the loading state, and is brought into pressure contact with the capstan when the recording/playback mode is set. . This pressure contact is usually done by a solenoid,
Although rare, this may be caused by overstroke of the loading mechanism. In the former case, the provision of a solenoid inevitably increases the size and complexity of the device, and in the latter case, the loading mechanism also becomes complicated and the loading state becomes unstable. Therefore, the present invention independently engages the loading mechanism and the capstan pressure contact mechanism with the mode setting cam, and further rotates the mode setting cam that has set the loading state. The purpose of the present invention is to propose a new and effective pinch roller pressure contact mechanism for a video tape recorder in which only the pinch roller is brought into pressure contact with the capstan. Hereinafter, the present invention will be explained according to an illustrative embodiment. The first feature of this embodiment is that it is provided with a mode setting cam that switches modes by rotation. This mode setting cam 1 is rotated 45 degrees clockwise from the first position (Fig. 1 b) for setting the stop mode to the second position [Fig. Set the return mode and return to the first
At the third position (Fig. 1 c), which is rotated 270 degrees counterclockwise from the position, the pause mode is set upon completion of loading, and at the fourth position, which is rotated 45 degrees counterclockwise from the third position [Figure 1 c]. In FIG. 1(d), the recording mode and reproduction mode are set by pressing the pinch roller. In addition, this mode setting cam 1 has an idler regulating cam 1b formed on the upper stage of the gear portion 1a, a spiral loading cam 1c on the lower surface, and a pinch roller moving cam 1d mounted on the upper surface of the idler regulating cam 1b. An idler regulating lever 2 for regulating the movement of the tape winding idler and a loading completion detection lever 3 are brought into contact with the idler regulating cam 1b, and a pinch roller moving lever 4 is brought into contact with the pinch roller moving cam 1d.
Further, a loading pin 5 for driving the loading mechanism is brought into contact with the loading cam 1c.
are engaged. Therefore, in the stop mode, the idler regulating lever 2 is in the first position by entering the recess of the idler regulating cam 1b, thereby regulating the idler to the neutral position and pressing the brake shoe against the reel stand. Further, in the fast forward mode and the rewind mode, the idler regulating lever 2 is disengaged from the recessed portion and is in the second position, releasing the regulation of the idler. Furthermore, in the pause mode, the loading pin 5 is rotated clockwise to complete loading, and the pinch roller moving lever 4 is rotated clockwise to place the pinch roller opposite the capstan with the tape in between. , the idler regulation lever 2 is in the second position, and the loading completion detection lever 3 enters the recess of the idler regulation cam 1b to detect the completion of loading and stop the rotation of the mode setting cam 1 . . Furthermore, in the recording mode and the reproduction mode, the pinch roller moving lever 4 is further rotated clockwise to press the pinch roller against the capstan. Each drive system will be explained below with reference to the drawings from FIG. 2 onwards. First, as shown in FIG. 2, the drive system for the mode setting cam 1 is such that the mode setting cam 1 is rotatably supported on a first support shaft 7 set on the upper surface of the bottom substrate 6 . A first gear 9 fixed to the upper part of the second support shaft 8 through which the bottom substrate 6 is fitted is engaged with the gear part 1a, and a bevel-shaped second gear 9 fixed to the lower part of the second support shaft 8 is engaged with the gear part 1a. Loading motor support plate 1 attached to the lower surface of the bottom board 6 with respect to the gear 10
The loading motor 13 is engaged with the bevel gear part 12a of the third gear 12 which is pivotally supported by the third gear 12, and the loading motor 13 is connected to the spur gear part 12b of the third gear 12
The fourth gear 14, which is integrated with the drive shaft 13a, is engaged with the fourth gear 14. Therefore, the loading motor 13 includes the fourth gear 14 and the third gear 12 that constitute a reduction mechanism, and the third gear 1 that constitutes a reduction and rotational axis changing mechanism.
2 and the second gear 10, the rotation is transmitted to the first gear 9, and the setting mode of the mode setting cam 1 is switched by the loading motor 13, which is bidirectionally driven. Further, as shown in FIG. 3, the drive system of the loading mechanism is such that a fan-shaped gear 15 that supports the loading pin 5 that engages with the loading cam 1c is connected between the bottom board 6 and the mode setting cam 1 . The fan-shaped gear 15 is provided with a loosely fitting through hole 15a for the first support shaft 7 so as to be rotatable relative to the third support shaft 16 set on the bottom substrate 6 . It meshes with the small diameter gear part 18a of the fifth gear 18 pivotally supported on the four support shafts 17, and the sixth gear 19 and the seventh gear 20 mesh with the large diameter gear part 18b of the fifth gear 18,
An eighth gear 21 is further meshed with the seventh gear 20, and a left loading arm 2 is attached to a first block 22 integrally fixed to the sixth gear 19.
3 is fixed thereto, and a right loading arm 25 is fixed to the second block 24 which is integrally fixed to the eighth gear 21. Therefore, the mode setting cam 1 moves 270 degrees from the first position to the third position.
While rotating, the loading cam 1c gradually changes its diameter so as to guide the engaging loading pin 5 counterclockwise around the third support shaft 16. The rotating fan-shaped gear 15 causes the first block 22 to rotate counterclockwise and the second block 24 to rotate clockwise, and the left and right loading arms 23 ,
A loading block, which will be described later, is attached to each tip of 25 and is guided from the unloading position to the loading position. In addition, the loading cam 1c
When the tape is rotated from the first position to the second position to fast-forward or rewind the tape, and when it is rotated from the third position to the fourth position for recording and playback, the diameter does not change. Both the loading arms 23 rotate to keep the loading pin 5 in place;
25 is inactive. Further, the second block 24 and the eighth gear 21 are pivotally supported on a fifth support shaft 26 set on the bottom substrate 6 , and the seventh gear 20 is pivotally supported on a sixth support shaft 27. The first block 22 and the sixth gear 19 are provided with a cylindrical body 28 at the center which also penetrates the bottom substrate 6 in order to support a tension applying lever which will be described later. Furthermore, the reel drive system is as shown in Figure 4.
The reel motor 3 is located on the left side of the lower surface of the sub-board 33 which is fixed to the lower surface of the bottom board 6 by four pillars 29, 30, 31, 32, which is indicated by a dashed line.
4 is fixed, and a first pulley 35 is attached to the drive shaft 34a thereof, and a second pulley 37 is attached to a second pulley 37 attached to the lower part of a shaft 36 which is supported by passing through the bottom substrate 6 and an upper substrate to be described later. 38, and the rotation of the reel motor 34 is switched between three stages: normal rotation in recording/reproducing mode, high speed rotation in fast forward mode, and reverse high speed rotation in rewind mode. Furthermore, the capstan drive system, as shown in FIG . A second connecting belt 43 is mounted on a flywheel pulley 42 fixed to the lower part of a capstan shaft 41 that passes through the upper substrate. In addition, the drawing number 44 shows six pillars 45, 4 on the underside of the flywheel pulley 42.
6, 47, 48, 49, and 50, and is a rotation detecting body having built-in rotation detecting means for the flywheel pulley 42. The configuration of the loading mechanism, which is the second feature of this embodiment, will be explained below with reference to the drawings from FIG. 5 onwards. First, both the loading arms 23 and 25 are equipped with two leaf springs 23a and 23, respectively.
b, 25a, 25b to connectors 23c and 25c
The leaf springs 23a, 2 are supported rotatably by
This is absorbed by elastic deformation in the thickness direction of 3b, 25a, and 25b. Furthermore, the loading blocks 51 and 52 respectively disposed at the ends of the loading arms have a substantially symmetrical shape.
One right loading block 51 has a right guide shaft 53 rotatably supported by the right loading arm 25, a right tape guide 54 fixed to the upper part of the guide shaft 53, and a right side inclined by about 12 degrees. a right side moving guide stand 56 on which the inclined pin 55 is planted; a right side slider 57 rotatably supported by the middle part of the guide shaft 53 and forming a guide groove 57a on its outer peripheral surface; and a lower part of the guide shaft 53. a right positioning arm 58 that is fixed to and circumferentially surrounds a guide rail, which will be described later, to define the rotational state of the right side moving guide stand 53; and through holes 57c and 58 of the right slider 57 and the right positioning arm 58;
It consists of a right side coil spring 59 whose end is inserted in a and urges the positioning arm 58 to rotate clockwise relative to the right side slider 57. Similarly, as shown in FIG. 6, the left loading block 52 also has a left moving guide stand 64 on which a left guide shaft 60, a left slider 61, a left tape guide 62, and a left inclined pin 63 inclined at 12 degrees are installed. The left side moving guide stand 64 is urged to rotate counterclockwise with respect to the left side slider 61. These loading blocks 51 , 52 must pass through a narrow space from the unloading position to the loading position. Therefore, in this embodiment, as shown in FIG. 6, a right guide hole 66 for guiding the right slider 57 and a left guide hole 68 for guiding the left slider 61 are cut off at their upper ends on the upper substrate 65. A right guide rail 68 and a left guide rail 69 are attached to the outside of the loading route on the bottom board 6 as shown in FIG. A right side positioning arm 58 and a left side positioning arm (not shown) are circumferentially attached to both guide rails 68 and 69 of the lever, and the two movable guide bases 5 are moved during loading.
The longitudinal direction of 6, 64 is aligned substantially along the loading path to avoid collision with components disposed close to the loading path. Further, the upper substrate 65
Both moving guide tables 56, 64 move on the upper surface of the
The state of the sliders 57, 61 is changed at the loading position and the unloading position, and at the loading position, the positioning block 7 serves to prevent the guide holes 66, 67 from coming off.
0 and 71 define the tape guide side of both the movable guide stands 57 and 61, and the winding angle defining plates 72 and 73 that abut can adjust the prescribed position with adjusting screws 72a and 73a define the inclined pin side. In addition, at the unloading position, in order to define both the moving guide stands 57 and 61 in the horizontal direction in the figure, the right side moving guide stand 57 is connected to the storage defining metal fitting 74, and the left moving guide stand 61 is connected to the storing defining plate 75. It is stipulated that Therefore, both the moving guide stands 57, 61
During unloading, the storage regulation fitting 74 and the storage regulation plate 75 are used, and during loading, the guide rails 68 and 69 are used to secure the positioning blocks 70 and 71 and the wrapping angle when loading is completed. Regulation plates 72, 73
The rotation state is defined by Further, as shown in FIG. 7, the pinch roller moving mechanism moves the pinch roller moving lever 4 that comes into contact with the pinch roller moving cam 1d from the bottom substrate 6.
It is rotatably supported on an upper seventh support shaft 76, and a pinch roller support lever 77 is also supported on the seventh support shaft 76, and an expansion spring 78 is disposed between it and the pinch roller moving lever 4. Pinch roller 79
The overstroke during crimping is absorbed, and the expansion is restricted by a rotation regulating pin 4a set on the pinch roller moving lever 4,
The L-shaped lever 80 fixed to the pinch roller moving lever 4 is connected to the pinch roller pressure detection switch 81.
It is made to face. In addition, the pinch roller support shaft 77a installed on the pinch roller support lever 77 crosses the right guide hole 66 in the upper substrate 65 to ensure a moving path for loading and pinch roller crimping. 82 is formed. The right slider 57 has a sufficient length so that the right slider 57 can stably slide along the right guide hole 66 at the intersection of the two guide holes 66 and 82.
Therefore, as is clear from the shape of the pinch roller moving cam 1d, the pinch roller 79 of this embodiment rotates all at once after the latter half of the loading period, that is, after the tape has been sufficiently pulled out, and moves the capstan 4.
1, the tape moves slightly as the recording mode or playback mode is switched, and the tape is elastically clamped. This clamping is detected by the pinch roller pressure detection switch 81, and the The power to the loading motor 13 is turned off. Next, as is clear from FIGS. 4 and 6, the back tension applying mechanism uses a back tension detection arm 84 that erects the back tension pin 83.
A cylindrical body 87 is fixed to a rotary shaft 85 inserted through the cylindrical body 28 and a band 86 is wound around the lower end of the rotary shaft 85 that reaches the lower surface of the bottom substrate 6 . The back tension applying arm 84 is rotated counterclockwise by being indexed by an index spring 88 whose one end is fixed to the sub board 33 , and an eighth support is provided on the lower surface of the back tension detecting arm 85. The brake plate 91 comes into contact with a first movable pin 90 that is pivotally supported by a shaft 89 and is set on the back tension detection arm 85.
The brake shoe 92 arranged on the supply reel stand 93
A back tension applying lever 94 that is circumferentially attached to the
A tension release lever 96 is disposed on the lower surface of the back tension applying lever 94 and is biased to rotate counterclockwise by a tension release spring 95 which is also pivotally supported on the eighth support shaft 89. At the time of unloading, the bending rib 96a rotates the buck tension applying lever 94 counterclockwise to completely separate the brake shoe 92, and the first movable pin 90 is rotated counterclockwise. The back tension detection arm 84 is rotated clockwise to hold the back tension pin 83 in the notch of the cassette (not shown), and when both the loading blocks 51 and 52 almost reach the loading position, the back tension detection arm 84 is rotated clockwise. 1 block 22
The second movable pin 97 installed above rotates the tension release lever 96 clockwise, so that when the back tension applying lever 94 is released, the index spring 88 is biased to release the back tension detection lever. 84 has reached the loading position (that is, the release tension detection position), and the detection tension of the back tension pin 83 applies a braking force to the supply reel stand 93. Next, the idler mechanism includes an idler support lever 98 that is pivotally supported by the shaft 36 on the bottom board 6 , an idler support shaft 99 is installed on the upper surface of the idler support lever 98, and a third When the movable pin 100 is installed and the idler regulating lever 2 is in the stop mode as shown in FIG. The third movable pin 100 engages with the notch 2a of the idler regulating lever 2 to restrict its rotation, and the idler 102, which is pivotally supported on the idler support shaft 99 on the upper surface of the upper substrate 65 , is brought to a neutral position. The idler regulating cam 1b is rotated counterclockwise when the idler regulating lever 2 is in another mode in which it is out of the concave portion of the idler regulating cam 1b as shown in FIG. Free rotation of the idler 102 is ensured, and the idler gear 102 rotates in response to the rotation of the ninth gear 103, which rotates integrally with the shaft 36 on the upper substrate 65 and meshes with the idler 102. 93 gear part 93a
The first one is selectively engaged with the gear portion 104a of the take-up reel stand 104, and the rotation of the reel motor 34 is transmitted to the two reel stands 93 or 104. The reel motor 34 switches the rotational direction in each of the winding and fast-forward modes, and decelerates the rotation in the recording and reproducing modes, and the applied voltage is switched according to each mode. Further, the reel braking mechanism interlocked with the idler regulating lever 2 is a braking portion 1 of a braking lever 105 disposed on the upper substrate 65 as shown in FIG.
05a, 105b to both reel stands 104 and 9.
The brake lever 105 is opposed to the circumferential surface of the brake lever 105.
The braking force applying lever 10 is connected to the braking force applying lever 10 via a connecting plate 106.
7, and its sliding direction is regulated by a ninth support shaft 108, and the braking force imparting lever 107 is pivotally supported by a tenth support shaft 109 and passes through the upper substrate 65, and is connected to the idler regulating lever 2. A brake pin 110, which is erected in the reel, is loosely fitted, and the brake portions 105a and 105b come into pressure contact with both the reel stands 92 and 104 only in the stop mode. In addition, the device of this embodiment has four parts as shown in FIG.
In addition to the pinch roller pressure detection switch 81, the detection switch detects the completion of loading in conjunction with the loading completion detection lever 3, stops the loading motor 13, and enters a temporary stop mode. a loading completion detection switch 111 to be set; and an unloading detection switch 11 to detect unloading in conjunction with the idler regulation lever 2, stop the loading motor 13, and set a stop mode.
2, and a high-speed transfer mode detection switch 113 that is linked to the idler regulation lever 2, detects the release of regulation of the idler 102, stops the rotation of the loading motor 13, and sets a fast forward mode or a rewind mode. It is fixed on the upper substrate 65 and controls rotation and stopping of the loading motor 13. In addition, the tape guide mechanism, in the loading state, is guided by members shown in FIG.
3. a first fixed guide pin 115, a full-width erasing head 116, the left tape guide 62, the left inclined pin 63, a guide cylinder 117 inclined at 10°;
It is guided through the right side tilt pin 55, the left side guide pin 54, the audio/control signal recording/reproducing head 118, the second fixed guide pin 119, the capstan 41 and the pinch roller 79, and reaches the cassette winding side. In addition, the apparatus of this embodiment has a tape start end detection mechanism and a tape end detection mechanism of the same configuration on the tape supply side and the tape winding side, respectively, and the tape end detection mechanism is connected to the cassette C as shown in FIG. The supply side positioning guide 120 is laterally hollow,
The light emitted horizontally by the light emitting member 122 fixed on the upper substrate 65 by the first fixture 121 is reflected by the first light emitting member 122 arranged in the supply side positioning guide 120.
The reflected light is vertically reflected by a reflecting member 123, and reflected horizontally by a second reflecting member 124 disposed above the supply side positioning hole of the cassette C in a horizontal direction penetrating the tape running section. A light detection member 126 is arranged on the side surface of the cassette holder 125 on the opposite side, and the passage of the transparent tape at the end of the tape is detected by the light detection member 126 arranged on the side surface of the cassette holder. In addition, the number 127 in FIG. 9 is a holder for the light emitting member 122, 128 is a holder for the light detection member 126, and the number 12 in FIG.
9 is a winding side positioning guide; 130 is a second positioning guide;
Fixing hardware is shown. The operation of the device of this embodiment will be explained below for each mode. (a) Stop mode This mode is a mode in which the cassette can be attached and detached, and when the cassette is attached, both the tape guides 5
4, 62, both the inclined pins 63, 55, the pinch roller 79 and the back tension pin 83 are in an unloading state in which they have entered into the cassette notch, and the brake shoe 92 which applies back tension is in a non-loaded state. Both the braking parts 105a, 105b of the braking lever 105 are in contact with each other, but the braking parts 105a, 105b of the braking lever 105 are
04 to regulate the running of the tape,
The idler 102 is defined in a neutral position.
This unloading state is detected by the unloading detection switch 112, and when setting the stop mode from another mode, the rotation of the mode setting cam 1 is stopped by this detection output. (b) High-speed transport mode This mode is a mode in which the tape is stretched at the front of the cassette in an unloaded state and the tape is run at high speed. Therefore, the mode setting cam 1 , which is rotated clockwise from the first position by the mode setting operation, is rotated by the idler regulation lever 2.
The tip of the idler regulating cam 1b is removed from the recessed portion of the idler regulating cam 1b, rotated by 45 degrees, and the rotation is stopped by the detection output of the high-speed transfer mode detection switch 113. By the rotation of the idler regulation lever 2, the idler 102 is released from regulation, and the rotation of the reel motor 34, which is driven at high speed at the same time as the mode setting, swings in one direction according to the setting mode, and one reel stand is rotated. Drive at high speed. (c) Pause mode: In this mode, the tape stretched inside the cassette is pulled out, loaded, and expected for recording and playback. Therefore, the mode setting cam 1, which rotates counterclockwise from the first position, operates the loading mechanism by guiding the loading pin 5 that engages with the loading cam 1c, and engages with the idler cam 1b. The idler regulating cam 2 releases the braking of the reel stands 63 and 104 and the regulation of the idler 102 to the neutral position, and in the latter half of loading, the pinch roller moving cam 1d releases the pinch roller 7.
9 is opposed to the capstan 41 and rotated by 270° to the third position, the rotation is stopped by the detection output of the loading completion detection switch 111. On the other hand, the second movable pin 97 rotates counterclockwise with loading.
The restriction on rotation of the back tension applying lever 94 by the tension release lever 96 is released, and the back tension detection arm 84 is allowed to rotate in the latter half of loading. Also, the loading blocks 5 move along the guide holes 66 and 67 during loading.
1 and 52 move the movable guide bases 56 and 64 to the sliders 57 without causing the movable guide bases 56 and 64 to collide with the tape guides 115 and 119 facing the guide through holes 66 and 67, respectively. , 61, the longitudinal direction thereof is aligned with the guide through holes 66, 6.
7, and at the loading completion position, the movable guide bases 56, 64 are positioned by the positioning blocks 70, 71 and the adjustable winding angle defining plates 72, 73, and the loading arm is moved. Constituent leaf springs 23a, 23
The overstroke of loading is absorbed by the elastic deformation of b, 25a, 25b,
The tape wound around the guide cylinder 117, which is inclined by 10 degrees to the left in the figure, has its wrapping angle adjustable by the two inclined pins 55 and 63 which are inclined by approximately 12 degrees to the left in the figure. Ru. In this pause mode, the capstan motor 33 rotates simultaneously with the start of loading to ensure a smooth start of recording and playback.
and a head motor (not shown) continues to rotate. (d) Recording/playback mode: This mode is a mode in which the tape is run at a constant speed in the loading state. The specific operation is to press the pinch roller 79, and the mode setting cam 1, which rotates further counterclockwise from the third position depending on the mode setting, is moved by the pinch roller moving cam 1d to the pinch roller moving lever. 4 is further rotated to bring the pinch roller 79 into pressure contact with the capstan, and the pinch roller pressure detection switch 8
The overstroke of the pinch roller moving lever 4 is caused by the expansion spring interposed between the pinch roller support lever 77 and the pinch roller support lever 77. This is done by 78. On the other hand, the take-up reel stand 104 receives the rotation of the reel motor 34, which is driven at low speed at the same time as mode selection, through an idler 102 that can swing.
The pinch roller 79 and the capstan 41
The tape is wound up as it is transported at a constant speed. Therefore, according to the present invention, even though the mode setting cam is rotated further in the loading direction from the loading completion position, only the operation of pressing the pinch roller against the capstan is performed without causing any change in the loading state. Not only can the loading state be kept stable in recording/playback mode and pause mode, but there is no need to separately provide a solenoid for pinch roller crimping, which greatly contributes to cost reduction and downsizing of the device. It is.

[Brief explanation of drawings]

Each figure shows a mechanism according to an embodiment of the present invention.
The figure shows the engaged state of the lever according to the rotational position of the mode setting cam, Fig. 2 is a plan view showing the drive mechanism of the mode setting cam, Fig. 3 is a plan view showing the loading mechanism, and Fig. 4 is a plan view of the bottom surface of the bottom board,
Fig. 5 is a partially cutaway perspective view of the right loading block, Fig. 6 is a plan view of the upper board, Fig. 7 is a plan view of the bottom board in recording/reproducing mode, and Fig. 8 is a plan view of the bottom board in stop mode. Main part plan view, No. 9
The figures each show a cross-sectional view of the tape start/end detecting section. Explanation of main drawing numbers, 1 ...Mode setting cam, 13
... Loading motor, 93, 104 ... Reel stand, 79 ... Pinch roller, 41 ... Capstan.

Claims (1)

[Scope of Claims] 1. A loading cam 1c that forms a groove with a constant diameter at the terminal end of a spiral groove, and a pinch roller moving cam that forms a constant diameter portion at the starting end and rotates together with the loading cam 1c. 1d; a loading motor 13 for rotating the loading cam 1c and the pinch roller moving cam 1d from the first position to the third position; A pair of loading blocks 5 are rotated from the first position to the second position.
loading mechanisms 15 to 25 for moving the rollers 1 and 52 from the unloading position to the loading position in the cassette; is defined in the cassette, and rotationally guides the pinch roller 79 from the inside of the cassette to a position facing the capstan 41 in the latter half of the rotation of the pinch roller moving cam 1d from the first position to the second position. The loading mechanism 15 is placed in a state in which the loading mechanisms 15 to 25 are engaged with the constant diameter groove of the loading cam 1c, which is further rotated from the second position to the third position. 25, further rotate only the pinch roller moving lever 4 that engages with the pinch roller moving cam 1d that rotates from the second position to the third position, and move the pinch roller 79 to the capstan 41. A pinch roller pressure contact mechanism for a video tape recorder characterized by pressure contact.