JPH0610527Y2 - Tape-shaped loading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement of a loading device for a tape-like body, and is particularly suitable for application to an open reel type video tape recorder.

[Outline of device]

This invention is provided on the peripheral surface of a guide drum for guiding a tape-shaped body, and a spiral tape reel which is low on the supply reel side of the tape-shaped body and high on the take-up reel side and the tape-shaped body described above. When loading on the guide drum, it is retracted to the first position, and at the time of recording and reproducing, it is moved to the second position to wind the tape-shaped body around the guide drum along the tape lead at a predetermined winding angle. Move, fast forward,
In order to guide the tape-shaped body at the time of rewinding, the first
Inlet and outlet guides that move to a third position between the first and second positions, and a drive mechanism for reciprocating these guides between the first and second positions and on the respective guide rails. When the inlet guide is moved back from the second position to the first position, the height of the inlet guide is increased corresponding to the change in the height of the tape-like body due to the detachment from the tape lead. In order to change the height, the guide rail is provided with a slope so that when the tape state is fast forwarded / rewound, the tape-shaped body is not damaged by the contact with the inlet guide. is there.

[Conventional technology]

A conventional open-reel type magnetic recording / reproducing apparatus includes a duct including a starting end located near a supply reel, an ending end located near a take-up reel, and a drum outer peripheral passage provided on a peripheral surface of a rotary head drum that is a guide drum. In some cases, the magnetic tape is loaded from the start end to the end by guiding air from the blower into the loading passage.

Further, in such a device, at the time of recording and reproducing after the completion of the loading, it is necessary to wind the magnetic tape 72 around the guide drum 71 at a predetermined winding angle as shown in FIGS. An exit guide 75 is provided.

That is, these guides 74 and 75 are movable between the solid line position and the two-dot chain line position in FIG.
When the magnetic tape 72 is in the solid line position near 1, the magnetic tape 72 works so as to be wound around the guide drum 71 at the predetermined winding angle. Also, the distance ₁ and the distance 2 from this solid line position
When it is at the position indicated by the dotted chain line, the magnetic tape 7 made of the air is used.
2 does not interfere with loading.

[Problems to be solved by the invention]

However, the magnetic tape 72 is wound around the guide drum 71 along a spiral tape lead 76 whose height is low on the supply reel side and high on the take-up reel side. It is easy to occur.

That is, as the entrance guide 74 moves from the solid line position in FIG. 7 toward the two-dot chain line position, the magnetic tape 72 is gradually separated from the tape lead 76, and as a result, the position of the tape 72 rises. In other words, in FIG. 8, the upper edge 72a of the magnetic tape 72 has a height H ₁ from the solid line position to the dotted line position in the drawing.
Only rises. According to the actual measurement, when the entrance guide 74 is moved about 4 mm from the solid line position to the two-dot chain line position, H ₁
The value of was about 0.8 mm.

Therefore, when the height of the inlet guide 74 is invariable between the solid line position and the two-dot chain line position, the height of the upper edge 72a of the magnetic tape 72 is the same as that of the inlet guide 74 as shown in FIG. It will exceed the height of the upper flange 74a.

Considering the case of fast-forwarding where the magnetic tape 72 runs at high speed and rewinding, the upper edge 72a of the magnetic tape 72a
Will naturally have more chances to disengage from the upper flange 74a of the inlet guide 74.

Thus, the magnetic tape 72 comes into contact with the inlet guide 74 and is easily damaged.

In view of the above points, the present invention is to provide a loading device that is not damaged by the entrance guide 74 even when the magnetic tape 72 is run at high speed.

[Means for solving problems]

The present invention provides a supply reel for supplying a tape-like body and a take-up reel for winding the tape-like body, and a guide drum for guiding the tape-like body delivered from the supply reel. Is low on the supply reel side and high on the take-up reel side, and through a drum outer peripheral passage provided around the guide drum and along the tape lead, in the vicinity of the supply reel. A duct-shaped loading passage extending from the start end to the end near the take-up reel, and air from the blower is introduced into the loading passage to transfer the tape-like member from the start end to the end, and the tape-like member. A plurality of air discharge ports for loading the recording medium, and withdrawing to the first position outside the loading passage during the loading, and the guide driver during recording and reproducing. The tape-shaped body is moved to a second position in the vicinity and wound around the guide drum along the tape lead at a predetermined winding angle, and fast-forwarded and rewound from the first position to the second position. Guides for an inlet and an outlet that move to a third position on the movement path near the first position and guide the tape-shaped body, and these inlet and outlet guides between the first and second positions. And a drive mechanism for reciprocating on each of the guide rails, and when the inlet guide returns from the second position to the first position, the tape-like shape accompanying the detachment from the tape lead The tape-shaped loading device is configured so that the guide rail is provided with a slope in order to change the height of the inlet guide in response to the change in body height.

[Action]

Therefore, the height of the inlet guide that is moved back on the guide rail having the inclination changes in accordance with the change in the height of the tape-shaped body. Therefore, since the tape-shaped body and the inlet guide are always maintained in the normal vertical positional relationship, there is no possibility that the tape-shaped body will come into contact with the inlet guide and be damaged when the tape-shaped body travels at high speed.

〔Example〕

An embodiment in which the present invention is applied to an open reel type video tape recorder will be described below with reference to FIGS. 1A to 6.

First, as shown in FIGS. 5 and 6, a vertical video tape recorder body (hereinafter simply referred to as a VTR body) 1
A supply reel base 2 and a take-up reel base 3 are arranged on the left and right sides of the front surface 1a of the above with a space therebetween. Then, the supply reel 5 around which the magnetic tape 4 which is a tape-like body is wound.
A winding reel 6 for winding the magnetic tape 4 is mounted on the supply reel base 2 and the winding reel base 3.
Further, the rotary head drum 7 as a guide drum is provided at a position close to the lower portion of the supply reel 5 on the front surface 1a of the VTR main body 1.
Are arranged.

Next, a loading passage 9 is arranged on the front surface 1a of the VTR main body 1 at a position close to the lower sides of both reels 5 and 6. The loading passage 9 is arranged such that its starting end 9a is arranged close to the lower part of the supply reel 5, its trailing end 9b is arranged close to the lower part of the take-up reel 6, and along the peripheral surface 7a of the rotary head drum 7. It has a drum outer peripheral passage 9c having a substantially U shape in a horizontal direction. The supply-side passage 9d between the starting end 9a and the drum outer peripheral passage 9c is formed laterally and has a substantially inverted U shape, and the winding-side passage 9e between the end 9b and the drum outer peripheral passage 9c is the end. It is formed so as to gradually rise toward 9b. Therefore, the loading passage 9 is curved in a zigzag shape with a gentle curve as a whole. The loading passage 9 is formed in a duct shape by a front panel 10 attached to the front surface 1a of the VTR main body 1 and an openable / closable front cover 11 fitted to the front surface of the front panel 10. The front cover 11 is made of a transparent synthetic resin or the like, and is hinged to the VT.
It is rotatably attached to the R body 1 and is configured to be locked by a locking means (not shown) in a closed lid state shown by a chain line in FIGS. 5 and 6. In order to spirally wind the magnetic tape 4 around the peripheral surface 7a of the rotary head drum 7, the loading passage 9 is gently inclined so that the starting end 9a side is low and the ending end 9b side is high. The supply reel 5 is low, and the take-up reel 6 is
Is provided so that the height becomes higher.

Next, along the supply-side passage 9d of the loading passage 9,
The guide post 4, the tension detector 15, the guide roller 16, the full width erasing head 17, the inlet guide 18, and the like are arranged, and the outlet guide 19 is provided along the winding side passage 9e.
Tape guides such as a tape guide 20, an impedance roller 21, an audio erasing head 22, an audio recording / reproducing head 23, an audio monitor head 24, a capstan 25, a pinch roller 26, a guide roller 27, and the like are arranged.

Next, a plurality of air discharge ports 2 are provided along the loading passage 9.
9a to 29e are provided, and the plurality of air discharge passages 32a to 32e of one or a plurality of blowers 30 and 31 are connected to the air discharge ports 29a to 29e. The air intake port 33 of one blower 31 is connected to a number of air intake ports (not shown) provided on the peripheral surface of the hub 6a of the take-up reel 6 via an air intake passage (not shown). The air sucking force of the blower 31 causes the magnetic tape 4
The tip 4a of the above is wound around the peripheral surface of the hub 6a so that it can be adsorbed.

Next, the sensor 35 is provided on the end 9b side of the loading passage 9.
Are arranged. The sensor 35 includes a light emitting element 36 and a light receiving element 37 arranged on both sides of the loading passage 9.
The light receiving element 37 receives the detection light 38 which is emitted from the light emitting element 36 and traverses the loading passage 9.

Next, the loading operation of the magnetic tape 4 will be described.

As shown in FIG. 5, first, when both blowers 30 and 31 are operated, air is discharged from the plurality of air discharge ports 29a to 29e into the loading passage 9 in the directions shown by arrows a to e. The air sucked into the air suction port 33 of one of the blowers 31 sucks the air in the direction of arrow f from the outside to the inside of the peripheral surface of the hub 6a of the take-up reel 6.

Next, after the leading end 4a of the magnetic tape 4 wound around the supply reel 5 faces the starting end 9a of the loading passage 9, the supply reel 5 is manually or automatically rotated in the direction of arrow g. The magnetic tape 4 is delivered from the supply reel 5.

Then, as shown by the solid line in FIG. 5, the magnetic tape 4
The magnetic tape 4 is transferred by the ejection force of the air ejected in the directions indicated by the arrows a to e, and the magnetic tape 4 extends along the inside of the loading passage 9 from the starting end 9a side to the terminating end 9b side. The drum outer peripheral passage 9c and the winding side passage 9e are transferred in the arrow h direction.

The leading end 4a of the magnetic tape 4 is connected to the loading passage 9
End 9b of the magnetic tape 4 and when the air transfer of the magnetic tape 4 is completed, the leading end 4 of the magnetic tape 4
a is the detection light 3 from the light emitting element 36 in the sensor 35.
8 is cut off, the light receiving element 37 is switched to the non-light receiving state, and this sensor 35 detects the front end 4a of the magnetic tape 4.

Then, a timer (not shown) is operated, and the blower 30 is automatically stopped after a certain time set by the timer has elapsed.

Then, while the fixed time set by the timer elapses (actually, the inertial rotation time for a short time after the motor of the blower 30 is turned off is also added), the magnetic tape 4 Tip 4a of loading passage 9
Is sent from the terminal end 9b to a predetermined length in the direction of arrow h '. When the blower 30 is stopped, the air discharge from the air discharge ports 29a to 29d to the inside of the loading passage 9 is stopped, and the transfer of the magnetic tape 4 by air is stopped. If the supply reel 5 is manually rotated in the arrow g direction, the blower 30 may be stopped and the manual rotation may be stopped. If the supply reel 5 is automatically rotated in the arrow g direction, the blower 30 may be rotated. The rotation of the supply reel 5 is automatically stopped together with the stop.

Next, as shown by the chain line in FIG. 5, the tip end 4a of the magnetic tape 4 is manually lifted in the direction of arrow i, and the tip end 4a is wound around the peripheral surface of the hub 6a of the rewind reel 6 and blower 31 It is adsorbed by the suction force of air. Then, after the leading end 4a of the magnetic tape 4 is completely locked to the peripheral surface of the hub 6a of the take-up reel 6, the blower 31 is also stopped.

The tip 4a of the magnetic tape 4 is connected to the hub 6 of the take-up reel 6.
The magnetic tape 4 may be wound around the peripheral surface of a by a method of inserting the tip 4a of the magnetic tape 4 into a slit provided in the hub 6a and locking the magnetic tape 4 without using the above-described suction method using the suction force of air. Alternatively, a method of locking with various other locking means can be used.

By the above, all the loading operations of the magnetic tape 4 are completed.

Next, when the standby button is pressed, as shown in FIG. 5, the rotary head drum 7 is first rotationally driven in the direction of arrow j, and then the tension detector 15, the full width erasing head 17, and the inlet guide 18 are driven. The movable members such as the outlet guide 19, the tape guide 20, and the like are moved forward from the backward movement position shown by the dotted line to the forward movement position shown by the chain line, and the magnetic tape 4 moves the rotary head drum 7 as shown by the chain line. Is spirally wound around the peripheral surface 7a of the
It is handed over to the heads and guides.

Next, when the play button is pressed, as shown in FIG. 5, first, the capstan 25 is rotationally driven in the direction of arrow k,
Next, the magnetic tape 4 is pressed against the capstan 25 by the pinch roller 26, and the supply reel 5 and the take-up reel 6 are rotationally driven in the arrow g and one direction, respectively.
As a result, the magnetic tape 4 travels at a constant speed in the direction of the arrow h in a tensioned state in the loading passage 9 and desired recording or reproduction is performed.

When recording or reproducing, or fast-forwarding or rewinding, the magnetic tape 4 is accidentally cut or the magnetic tape 4 is completely wound around the take-up reel 6 or the supply reel 5, so that the sensor 35 receives light. When the element 37 is switched to the light receiving state in which the detection light 38 from the light emitting element 36 is received again, it is determined that the magnetic tape 4 in the loading passage 9 is gone, and, for example, a tape running drive system stop circuit (not shown). Is operated to automatically stop the traveling drive system of the magnetic tape 4 and the rotary head drum 7.

Next, referring to FIGS. 1A to 4, the inlet guide 18 for winding the magnetic tape 4 around the rotary head drum 7 at a predetermined winding angle, or for guiding the magnetic tape 4 running at high speed, and The outlet guide 19 will be described.

These guides 18 and 19 are respectively support blocks 18
It is mounted on the pair of sliders 40a and 40b via a and 19a. In addition, on the slider 40b,
Further, a tape guide 20 is also attached. Both sliders 40a and 40b are provided on the front surface 1a of the VTR main body 1.
Is configured to be reciprocable in the directions of arrows m, m ′ and n, n ′ along a pair of guide rails 41a, 41b fixed to
At the intermediate position between the guide rails 41a and 41b and at the V
Sliders 40a, 40b are provided on the front surface 1a of the TR body 1.
A common stopper 42 for is fixed.

By the way, the guides 18 and 19 are respectively indicated by arrows m ′ and
When returning in the n'direction and in the solid line position shown in FIG. 1A, both guides 18 and 19 are outside the loading passage 9 and do not interfere with the loading operation of the magnetic tape 4.

Further, when both guides 18 and 19 come to the dotted line position in FIG. 1A, that is, the position near the rotary head drum 7, the magnetic tape 4 is wound around the rotary head drum 7 along a tape lead 60 which will be described later. Is ready for recording and playback.

Next, on the front surface 1a (Fig. 5) of the VTR main body 1, for example, as shown in Fig. 1B, a pair of rotating arms 44a, 44b.
Is rotatably mounted via fulcrum shafts 43a and 43b, respectively. Also, these rotating arms 44a,
44b are rods 46a and 46b and links 47a and 47b which support limiter springs 45a and 45b, respectively.
Is connected to both sliders 40a and 40b via. Further, a drive shaft 49 which is rotationally driven by a geared motor 48 is attached to the front surface 1a of the VTR main body 1,
A drive arm 50 that is rotated integrally with the drive shaft 49 and one of the rotating arms 44a are connected by a link 51. The rotating arms 44a and 44b are connected by a link 52.

Next, two sensors 54 and 55 are attached to both sides of the drive shaft 49 on the front surface 1a of the VTR main body 1. Each of these sensors 54 and 55 has a light emitting element and a light receiving element (neither is shown), and when the light receiving element is receiving the light of the light emitting element, for example, outputs a signal "0",
When the light of the light emitting element is blocked by the shutter and the light receiving element cannot receive the light, for example, a signal "1" is output. The three shutters 56, 57, 5 that control these sensors 54, 55
8 is integrally provided on the outer periphery of the drive arm 50.

As shown in FIG. 2, the rotary head drum 7 is composed of an upper rotary drum 7b and a lower fixed drum 7c. The lower fixed drum 7c is a tape for winding the magnetic tape 4 on the rotary drum 7. The lead 60 is formed so as to form a spiral on the peripheral surface 7a.

In addition, a guide rail 41 for guiding the entrance guide 18
A is provided with a gradient such that the height of the inclined guide surface 61 is low on the side close to the rotary head drum 7 (the side in the direction of arrow m) and high on the far side (the side in the direction of arrow m '). Has been formed. It should be noted that this gradient is generated when the inlet guide 18 is moved back from the solid line position shown in FIG. 1A to the dotted line position.
As the height of the magnetic tape 4 that separates from the spirally extending tape lead 60 gradually increases, the inlet guide 18
Work to increase the height of.

That is, if an appropriate gradient is given, the normal vertical positional relationship between the magnetic tape 4 and the entrance guide 18 is always maintained, and as a result, the magnetic tape 4 is kept running at high speed. Even if it comes in contact with the entrance guide 18,
Eliminates the risk of damage. Although the above-mentioned gradient is given to the guide rail 41a of the entrance guide 18, the gradient can also be given to the guide rail 41b of the exit guide 19. However, in this case, when the magnetic tape 4 spirally wound around the rotary head drum 7 is detached from the rotary head drum 7 due to the backward movement of the outlet guide 19, its height gradually decreases. Therefore, the height of the inclined guide surface of the guide rail 41b is high on the side close to the rotary head drum 7 (the side in the direction of arrow n in FIG. 3), and on the far side (the side in the direction of arrow m'in FIG. 3). It needs to be low.

Next, when the magnetic tape 4 is loaded, the drive arm 50 is moved to the first position by the geared motor 48.
Driven in the direction of arrow o'as shown by the solid line in FIG.
The entrance / exit guides 18 and 19 (and the tape guide 20) are moved back in the directions of the arrows m ′ and n ′, respectively, and these are largely retracted out of the loading passage 9 as shown in FIGS.
It is driven to the first position P ₁ shown by the dashed line. The positions of the entrance / exit guides 18 and 19 at this time are
As shown in the figure, the geared motor 48 is stopped by being detected by the signal "0" of the sensor 54 and the signal "1" of the sensor 55 switched by the shutter 56.

Therefore, as described above, when the magnetic tape 4 is loaded by air, the transfer of the magnetic tape 4 in the direction of the arrow h is not obstructed by the entrance guides 18 and 19 (and the tape guide 20), and the magnetic tape 4 is loaded in the loading path. It can be loaded safely and smoothly along the inside.

Next, as described above, when the standby button is pressed after the loading of the magnetic tape 4 is completed, the drive arm 50 is rotated in the arrow o direction by the geared motor 48 as shown in FIG. 1B. Then, one rotating arm 44a is rotated in the direction of arrow q via the link 51, and further,
The other rotating arm 44b is rotated in the arrow r direction via the link 52. As a result, each of the limiter springs 4
5a, 45b, rods 46a, 46b and link 47
Both sliders 40a and 40b are moved forward in the directions of arrows m and n via a and 47b, and the entrance / exit guides 18 and 19 are located near the rotary head drum 7, that is, as shown by the solid line in FIGS. 2 Driven to position P ₂ . The positions of the entrance / exit guides 18 and 19 at this time are detected by the signal "1" of the sensor 54 and the signal "0" of the sensor 55 which are switched by the shutter 56 as shown in FIG. Is stopped. At this time, the sliders 40a and 40b are pressed against the stopper 42 via the spring force of the limiter springs 45a and 45b and stopped, and the toggle effect due to slight bending of the rods 46a and 46b and the links 47a and 47b. Will be locked at that stop position.

As a result of the above, as shown in FIGS. 2 to 4, the magnetic tape 4 is wound around the peripheral surface 7a of the rotary head drum 7 at a predetermined wrap angle.
Further, it is accurately wound along the tape lead 60 in a predetermined helical state. After this, as described above, when the play button is pressed, the magnetic tape 4 is moved to the rotary head drum 7.
The magnetic tape 4 is accurately driven at a constant speed along the peripheral surface 7a along the tape lead 60, so that the recording or reproducing of the magnetic tape 4 is performed with high accuracy.

Next, when the rewind button or the fast forward button is pressed, the drive arm 50 is slightly rotated by the geared motor 48 in the arrow o'direction as shown in FIG. 1A. Then, one rotating arm 44a is slightly rotated in the direction of the arrow q'through the link 51, and the other rotating arm 44b is further rotated by the link 52.
Is slightly rotated in the direction of arrow r'via. As a result, the limiter springs 45a, 45b, the rod 46a,
Both sliders 40a and 40b are moved in the directions of arrows m'and n'through 46b and links 47a and 47b, so that the entrance / exit guides 18 and 19 are moved to the third position P ₃ (exit point) indicated by a chain line in FIG. In the case of the guide 19, it is not shown), in other words, it is driven to a position on the movement path between the first position P ₁ and the second position P ₂ and close to the first position P _1. It Although the first position P ₁ of the inlet and outlet guides 18 and 19 is detected by the signal “0” of the sensor 54 and the signal “1” of the sensor 55 as described above, the geared motor 48 is stopped. , The third position P ₃ is provided by the pair of shutters 57, 58 and the pair of sensors 54, 5
5 are switched at the same time and detected by the signals "1" and "1" of these sensors 54, 55, and the geared motor 48 is detected.
Will be stopped.

By the way, the entrance guide 18 is set to the third position P _{3 as} described above.
, The height of the inlet guide 18 changes to the height corresponding to the height of the magnetic tape 4 as described above due to the inclination of the guide rail 41a. Therefore, the normal vertical positional relationship between the magnetic tape 4 and the entrance guide 18 is maintained, and the magnetic tape 4 is not likely to be damaged even if it comes into contact with the entrance guide 18.

In the above description, the entrance guide 18 always occupies the third position P ₃ at the time of fast-forwarding and rewinding the magnetic tape 4, but the fast-forwarding and rewinding are divided into two cases depending on the presence / absence of video reproduction, and the video reproduction is involved. The entrance guide 18 occupies the third position P ₃ at the time of fast forward and rewind, and the entrance guide 18 at the first position P ₁ at the time of fast forward and rewind without video playback.
Can also be configured to occupy.

The embodiments of the present invention have been described above, but the present invention is not limited to the above-mentioned embodiments, and various modifications can be made based on the technical idea of the present invention.

Further, although the invention is applied to an open reel type video tape recorder in the embodiments, various tape-shaped bodies such as tapes and films such as a magnetic recording / reproducing apparatus using a magnetic tape, a projection apparatus using a projection film, etc. It can be widely applied to loading devices for loading.

[Effect of device]

Since the present invention is configured as described above, the tape-shaped body and the inlet guide are always maintained in the normal vertical positional relationship. Therefore, there is no possibility that the tape-shaped body will come into contact with the inlet guide when the tape-shaped body is running at high speed and be damaged.

[Brief description of drawings]

FIGS. 1A to 6 show an embodiment of the present invention. FIGS. 1A and 1B are front views for explaining the main parts, and FIG. 2 is a II-II arrow of FIG. 1B. FIG. 3 is a perspective view of FIG. 1B, FIG. 4 is a partially enlarged view of FIG. 2 for explaining the main part, and FIG. 5 is a front view of the entire loading device. FIG. 6 is a perspective view of the entire loading device. 7 and 8 are a front view and a side view illustrating a conventional example. In the reference numerals used in the drawings, 4 ... magnetic tape (tape-shaped body) 5 ... supply reel 6 ... take-up reel 7 ... rotary head drum (guide drum) 9 ... loading passage 9a ... loading passage Starting end 9b ... End of loading passage 9c..Drum outer peripheral passage 41a..Inclined guide rail 48 .... Geared motor 60..Tape lead 61..Inclined guide surface.

Claims (1)

[Scope of utility model registration request] 1. A supply reel for supplying a tape-shaped body and a take-up reel for winding the tape-shaped body, and a guide drum provided on a peripheral surface of a guide drum for guiding the tape-shaped body fed from the supply reel. The vicinity of the supply reel passes through a spiral tape lead whose height is low on the supply reel side and high on the take-up reel side, and a drum outer peripheral passage provided around the guide drum and along the tape lead. A duct-shaped loading passage extending from the start end of the tape to the end near the take-up reel, and the air from the blower is guided into the loading passage to transfer the tape-shaped body from the start end to the end, A plurality of air outlets for loading the body, and a first outside the loading passage during the loading.
The tape-shaped body is retracted to the second position near the guide drum at the time of recording and reproducing, and the tape-shaped body is wound around the guide drum along the tape lead at a predetermined winding angle, fast-forwarded, and wound. At the time of returning, an inlet and an outlet guide for guiding the tape-like body by moving to a third position on the moving path from the first position to the second position and near the first position, and these inlets And a drive mechanism for reciprocating the outlet guide between the first and second positions and on the respective guide rails, and the inlet guide returns from the second position to the first position. At this time, in order to change the height of the inlet guide in response to the change in the height of the tape-shaped body due to the detachment from the tape lead, the guide rail is provided with a gradient, Grayed apparatus.