JPH0319072Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a reel stand device used in a video tape recorder or the like.

[Background technology and its problems]

Conventionally, a reel stand device installed in a video tape recorder rotatably supports the reel stand on a reel stand support shaft installed in a chassis part, and the load in the thrust direction is received by an appropriate bearing member. It is configured.

The reason why the load in the thrust direction of the reel stand is received by the bearing member is due to the following circumstances.

First, a tape cassette for a video tape recorder is constructed as shown in FIG. That is,
a is a tape cassette, b is a cassette housing c
One tape reel is rotatably stored inside the . The tape reel b consists of a hub d formed in a substantially cylindrical shape and flanges e formed at both upper and lower ends of the hub d. f is a reel base fitting recess into which the upper part of the reel base described later is inserted, and engaging protrusions g, g, g (only two are shown in the drawing) are formed at the lower part of the inner circumferential surface of the reel base fitting recess. has been done. h,
h (only one is shown in the drawing) is an opening formed in the bottom plate of the cassette case c;
The lower end of the hub d of the tape reel b is positioned within the opening. Reference numeral ``i'' denotes a pressing spring piece made of a plate spring material, and one end thereof is brought into elastic contact with a protrusion j formed on the upper end surface of the hub d.
Note that k is the other tape reel, which has the same structure as the one tape reel b, and the lower end of its hub is connected to the other opening h (not shown) formed in the bottom plate of the cassette case c. ), and the other end of the reel presser spring i is brought into elastic contact with the upper end of the hub.

Thus, when the tape cassette a is not in use, the two tape reels b and k are pressed against the bottom plate of the cassette case c by the reel pressing springs i. In addition, tape reel b
Both ends of a magnetic tape (not shown) are wound around and k, respectively.

FIG. 7 shows an example of a conventional reel stand device installed in a video tape recorder. Although FIG. 7 shows only one reel stand device with which one tape reel b of the tape cassette a is engaged, the other reel (not shown) with which the other tape reel k is engaged is shown. The stand device is also configured similarly to the one reel stand device.

In the figure, l is a base chassis, m is a mechanical chassis, and the mechanical chassis m has an opening n through which the upper part of the reel stand is inserted. o is a reel stand support shaft, and is erected on a boss p fixed to the base chassis l, the upper end of which projects upward from the top surface of the mechanical chassis m through the center of the opening n of the mechanical chassis m. ing.

q is a reel stand, and a substantially cylindrical shaft r is integrally formed with a reel receiver part s and a disc part t arranged on the outside of the shaft r.
A cap U is fitted into the upper part of the cap. v is mounted on the shaft r, is always urged upward by a coil spring w, and has engaging protrusions x, x, x (only one is shown in the drawing) on its outer peripheral surface. It is a reel engaging element formed with. y is a thrust bearing, for example, a rolling bearing such as a single thrust ball bearing is used, and is fitted onto the reel stand support shaft o, and is connected to the boss p and the lower end surface of the shaft part r of the reel stand q. is located between.

Thus, the reel stand q is rotatably supported by the reel stand support shaft o, and the load in the thrust direction is received by the thrust bearing y.

When the tape cassette a is loaded into the video tape recorder, the tape reel b is placed on the reel stand q as shown in FIG. That is, the lower end surface of the hub d of the tape reel b comes into contact with the upper end of the reel receiver part s of the reel stand q, and in this state, the cassette case c is further moved downward, so that the tape reel b The state of being pressed against the bottom plate of the cassette case c is released, and now it is pressed against the reel stand q. Therefore, the load of the tape reel b, which is pressed downward by the reel pressing spring i, is applied to the reel stand q in the thrust direction. is configured to be received by a bearing member.

Note that the upper part of the reel stand q is fitted into the reel stand fitting recess f of the tape reel b, and the engaging protrusions g, g, g and the engaging protrusions x, x, x on the reel stand q side are fitted.
are engaged with each other, thereby allowing tape reel b to rotate integrally with reel stand q. Further, the reel stand q has gear teeth formed on the outer peripheral surface of the disc portion t thereof and a reel stand drive gear (not shown) is engaged with the reel stand q, and is rotated by the rotation of the reel stand drive gear. is being done.

As described above, the conventional reel stand device has a structure in which the load in the thrust direction of the reel stand is received by a thrust bearing using a rolling bearing, so there is a possibility that the rotational resistance becomes large due to the rolling bearing. In addition, since the rolling bearing is press-fitted into the reel stand support shaft, dimensional errors are likely to occur during assembly, and the tape reel of the tape cassette placed on the reel stand is stably supported in a fixed position. This also causes the disadvantage that the magnetic tape cannot be stably run at an accurate position.

Furthermore, this type of thrust bearing is generally expensive, requiring at least two such expensive thrust bearings. Therefore, there is a problem in that the manufacturing cost of the video tape recorder increases.

[Purpose of invention]

Therefore, an object of the present invention is to provide a reel stand device that can receive a load in the thrust direction of the reel stand without using a rolling bearing such as a ball bearing as described above.

In addition, the present invention makes it possible to easily and accurately position the reel stand and to stably support the tape reel of the tape cassette in a fixed position, thereby making it possible to maintain stable magnetic tape. An object of the present invention is to provide a reel stand device that enables tape running.

Furthermore, an object of the present invention is to provide a reel stand device in which the bearing mechanism of the reel stand can be constructed at low cost.

[Summary of the idea]

In this invention, a reel stand is rotatably inserted into a reel stand support shaft which has a spherical part at the tip and is planted in the chassis part, and the inner surface of a cap fitted to the tip of this reel stand has the above-mentioned shape. By providing a thrust bearing that comes into contact with the spherical part of the reel stand support shaft, the reel stand device can be constructed without using rolling bearings, and the reel stand can be supported as a pivot bearing, reducing rotational resistance. A more stable rotational state can be obtained with a smaller size, and the problems arising from the use of rolling bearings can be solved.

〔Example〕

Hereinafter, details of the reel stand device according to the present invention will be explained according to embodiments shown in the drawings. In the embodiment shown in the drawings, the reel stand device of the present invention is applied to a video tape recorder.

1 to 4 show an example of the bearing mechanism of the reel stand of the present invention.

In the figure, 1 is a base chassis, and 2 is a mechanical chassis disposed above and facing the base chassis 1, and each of these chassis is disposed at the bottom of a cabinet constituting the main body of the video tape recorder. In addition, in FIG. 1, the mechanical chassis 2 is omitted from the illustration. The upper surface of the mechanical chassis 2 is arranged such that the upper part of a reel stand, which will be described later, protrudes, and is also equipped with various magnetic heads, a tape running mechanism, a tape loading mechanism, etc. (not shown).

Reference numerals 3 and 4 designate reel stand support shafts for supporting a reel stand, which will be described later, which are made of a metal material such as stainless steel, and are arranged on the upper surface of the base chassis 1 at a predetermined distance from each other, with their lower ends are erected on the base chassis 1 by being press-fitted and supported by bosses 5, 5' fixed to the base chassis 1, respectively. At the upper tips of these reel stand support shafts 3 and 4, spherical portions 3a and 4a are formed. 6, 6 are circular openings formed in the mechanical chassis 2, and these openings 6, 6' are centered at positions corresponding to the bosses 5, 5' provided on the base chassis 1 of the mechanical chassis 2. It is formed. Thus, the upper portions of the reel stand support shafts 3 and 4 project above the mechanical chassis 2 through the centers of the openings 6 and 6' of the mechanical chassis 2.

7 and 8 are reel stands. Since these reel stands 7 and 8 both have the same structure, one reel stand will be described in detail, and the other reel stand 8 will be described with an additional symbol "'" added to the reference numeral attached to one reel stand 7. Explanation will be omitted by using the given reference numerals.

The main parts of the reel stand 7 consist of a base 9 and a cap 10 that is integrally fitted to the tip of the base 9.

Reference numeral 11 denotes a shaft portion of the base portion 9, which is formed into a substantially cylindrical shape with an open upper end, and whose outer peripheral surface is formed in a regular hexagonal shape when the shaft portion 11 is viewed from the axial direction. An insertion hole 12 is formed with a tapered end. The diameter of this insertion hole 12 is approximately the same as the diameter of the reel stand support shaft 3 described above. Reference numeral 13 denotes a reel receiver disposed outside the shaft portion 11, and is integrally formed with the shaft portion 11 by being connected to the outer peripheral surface of the shaft portion 11 by a connecting portion 14 on the lower end side. ing. The upper end of the reel receiving cylinder portion 13 extends from the central portion of the shaft portion 11 in the axial direction to a position corresponding to a portion slightly closer to the upper end. Further, a large-diameter cylindrical portion 13a having a larger diameter than the reel receiving cylindrical portion 13 is provided on the lower end side of the reel receiving cylindrical portion 13 with the connection plate 14 interposed therebetween. Reference numeral 15 denotes a disk portion formed to project horizontally from the outer circumferential surface of the large diameter cylindrical portion 13a, and gear teeth 16, 16, . . . are formed on the outer circumferential surface. Reference numeral 17 denotes a brake drum portion formed on the upper surface of the connecting portion 14, and a brake band (not shown) provided on the upper surface of the base chassis 1 comes into contact with this brake drum portion 17.

The cap 10 (see FIG. 3) of the reel stand 7 is formed into a substantially cylindrical shape, and has a shaft fitting cylindrical portion 19 in the center thereof into which the tip of the reel support shaft 3 fits.
is formed. When the cap 10 is fitted to the tip of the shaft portion 11 of the reel stand 7, the tip of the support shaft 3 is fitted into the shaft fitting cylinder portion 19. That is, this support shaft 3 has its tip spherical portion 18 abutted against the flat thrust receiving portion 20 on the upper end surface of the shaft fitting cylinder portion 19, and the outer circumferential surface of the shaft fitting cylinder serving as a radial bearing portion. It is slidably supported on the inner circumferential surface of the portion 19 and is fitted into the shaft fitting cylinder portion 19 . Also, cap 1
The outer cylindrical portion of No. 0 serves as a shaft fitting portion 21 to the shaft portion 11 of the reel stand base 9. The inner peripheral surface of this shaft fitting part 21 is formed in the same shape as the outer peripheral surface of the shaft part 11 of the base part 9, that is, in a regular hexagonal shape, and the upper end surface of the shaft part 11 is press-fitted. It is formed to a certain size. The cap 10 is connected to the shaft portion 11 of the reel stand base 9 via this shaft fitting portion 21.
When fitted, the tip of the shaft portion 11 abuts against the abutting portion 22 on the upper end surface of the shaft fitting portion 21. And the thrust receiving part 20 of the cap 10
The abutment portion 22 of the shaft portion 11 is formed to form the same horizontal plane, and the thrust receiving portion 20 is abutted against the spherical portion 18 of the reel stand support shaft 3.
By abutting the tip of the reel stand against the abutment part 22 and press-fitting the cap 10 onto the shaft part 11, the reel stand 7 is supported with the spherical part 18 at the tip of the reel stand support shaft 3 as a reference. Attached to shaft 3.

Reference numeral 23 denotes a reel engaging element, which is formed in a substantially ring shape, and the inner circumferential surface of the hole thereof is formed in a regular hexagonal shape similar to the shape of the outer circumferential surface of the shaft portion 11 of the base portion 9; The size of the reel engaging member 23 is set to be such that the reel engaging member 23 can be fitted onto the shaft portion 11 so as to be movable in the vertical direction. 2
4, 24, 24 are engagement protrusions formed on the outer peripheral surface of the reel engager 23, and these engagement protrusions 24,
24, 24 are spaced apart from each other by 120 degrees.

Note that 25 is a coil spring.

Thus, the reel stands 7 and 8 are rotatably assembled to the reel stand support shafts 3 and 4 in the following manner, for example.

First, the reel stands 7 and 8 are assembled. These reel stands 7 and 8 have coil springs 25 and 25' fitted onto the shaft parts 11 and 11', and then the shaft parts 1
Reel engagers 23, 23' are fitted onto the ends of the shafts 11, 11', and caps 10, 1 are fitted onto the ends of the shafts 11, 11'.
0' is fitted and assembled. These caps 10, 10' have shaft portions 11, 1 as described above.
The shaft fitting parts 21, 21' are press-fitted onto the shaft parts 11, 11' by abutting the abutting parts 22, 22' on the tips of the shaft parts 1', and are attached to the base parts 9, 9'.

Each of the reel stands 7 and 8 assembled in this way has the reel stand support shafts 3 and 4 connected to the shaft portions 11 and 11 of the base portions 9 and 9', respectively.
11' from below, that is, through the insertion holes 12, 12' formed in the shaft parts 11, 11',
Spherical surface portions 18, 1 at the tips of the reel stand support shafts 3, 4
By attaching the thrust receiving portion 20 of the cap 10 to the reel support shaft 8', the reel support shafts 3 and 4 are rotatably attached, respectively. The upper end surfaces of the reel engagers 23, 23' provided on the reel stands 7, 8 mounted in this manner are elastically connected to the lower end surfaces of the caps 10, 10' by the elastic force of the coil springs 25, 25'. It is urged to be in contact with the shaft portions 11, 11' and is held in a state where it can rotate integrally with the shaft portions 11, 11'.

Since the spherical surface portions 18 at the tips of the reel stand support shafts 3 and 4 come into contact with the thrust receiving portions 20 provided on the caps 10 of the reel stands 7 and 8 installed as described above, the thrust direction of the reel stands 7 and 8 is The load, that is, the weight of the reel stands 7 and 8 and the pressing force received by the reel, which will be described later, is transferred to the thrust receiving portion 2.
You will receive it as 0.

The reel stands 7 and 8 are supported in the radial direction with respect to the reel stand support shafts 3 and 4 on the inner circumferential surface of a shaft fitting cylindrical portion 19 provided in the cap 10.

Thus, the reel stands 7 and 8 are rotatably supported by the reel stand support shafts 3 and 4, and the upper ends of the reel receiver parts 13, 13' and the upper ends of the reel receiver parts 13, 13' A portion located above the mechanical chassis 2 is made to protrude above the mechanical chassis 2 through the openings 6, 6' of the mechanical chassis 2.

Reference numeral 27 designates a tape cassette for a video tape recorder, and two tape reels 29 and 30 are rotatably housed inside a cassette casing 28 formed by joining an upper half and a lower half. Then, one of the two tape reels 29 and 30 is connected to the supply side tape reel (hereinafter referred to as "S").
Reel.” ), and the other one 30 serves as a tape reel (hereinafter referred to as a "T reel") on the winding side, and both ends of the magnetic tape 31 are wound on each reel.

Since the S reel 29 and the T reel 30 are constructed in substantially the same way, the S reel 29 will be explained in detail, and the T reel 30 will be given the reference numeral that is the same as the S reel 29 plus an additional symbol "'". Therefore, the explanation will be omitted.

That is, 32 is a hub formed in a substantially cylindrical shape, and flanges 33 are provided at both upper and lower ends of the hub 32.
34 is integrally formed, and a substantially bullet-shaped protrusion 35 is formed at the center of the upper end surface of the hub 32. Reference numeral 36 denotes a reel stand fitting recess formed inside the hub 32 and opened at the lower end of the hub 32, and its shape is similar to the shape of the upper part of the reel stands 7 and 8 described above, that is, the shape of the reel stands 7 and 8. Head 10,1
0' and the shapes of the reel engaging members 23, 23' are substantially complementary to each other. The inner circumferential surface of the lower part of the reel stand fitting recess 36, that is, the part into which the reel engagers 23, 23' are fitted when the upper parts of the reel stands 7, 8 are fitted thereto, is engaged. Coupling protrusions 37, 37, 37 (only one is shown in the drawing) are formed.
In addition, these engaging protrusions 37, 37, 37 are mutually
They are arranged at 120° square intervals.

Reference numerals 38 and 38' denote circular openings formed in the bottom plate of the cassette housing 28, and the diameter thereof is slightly larger than the outer diameter of the hubs 32 and 32' of the tape reels 29 and 30. are placed a distance apart. However, each tape reel 2
9, 30 are housed with the lower ends of their hubs 32, 32' positioned within the openings 38, 38' of the cassette housing 28, thereby allowing the upper parts of the reel stands 7, 8 to the tape reel 2
It is designed so that it can be fitted into the reel stand fitting recesses 36, 36' of Nos. 9 and 30.

39 is a reel presser spring made of a plate spring material, the center of which is supported by the cassette housing 28;
The hub 3 has tape reels 29 and 30 at both ends.
The protrusion 35 formed on the upper end surface of 2, 32',
35'. When the tape reels 29 and 30 are not in use, they are pressed against the bottom plate of the cassette housing 28 by the elastic force of the reel pressing spring 39.

Therefore, when using the tape cassette 27, the tape cassette 27 is held in a cassette carrier (not shown) provided in the video tape recorder, and then the cassette carrier is pushed into a predetermined position, or the autoloading mechanism is used. Attach it to a video tape recorder.
When the tape cassette 27 is installed in the video tape recorder, the cassette housing 28 is positioned in the height direction relative to the mechanical chassis 2 by means of cassette positioning pins 40, 40' (see FIG. 4) provided on the upper surface of the mechanical chassis 2. and horizontal position are defined.

The reel stands 7, 8 are engaged with the tape reels 29, 30, and the tape reels 29, 30 are engaged with the reel stands 7, 8.
30 is the reel receiver part 13, 1 of the reel stand 7, 8
3'. That is, when the tape cassette 27 is installed in the video tape recorder, the hubs 32, 32' of the tape reels 29, 30
The upper parts of the reel stands 7, 8 are inserted into the reel stand fitting recesses 36, 36' formed in the reel stand fitting recesses 36, 36', and the engaging protrusions 37, 37' formed on the inner surfaces of the reel stand fitting recesses 36, 36'. , 37, 37', 37', 37' and the engaging protrusions 24, 24, 24, 24', 2 formed on the reel engagers 23, 23' of the reel stands 7, 8.
4' and 24' are engaged with each other. At the same time, the lower ends of the hubs 32, 32' of the tape reels 29, 30 are brought into contact with the upper ends of the reel receivers 13, 13' of the reel stands 7, 8, and
In this state, the cassette housing 28 is moved further downward, so that the tape reels 29, 30 are released from being pressed against the bottom plate of the cassette housing 28, and are now pressed against the reel stands 7, 8. You will be able to do it.

Note that the load that the reel stands 7, 8 receive when the tape reels 29, 30 are pressed, that is, the load in the thrust direction of the reel stands 7, 8, is caused by the thrust receiving portion 20 of the cap 10 and the reel stand support shaft described above. 3, 4 is received at the point of contact with the spherical portion 18 at the tip. Therefore, since the load in the thrust direction of the reel stands 7, 8 is received at one point with respect to the reel stand support shafts 3, 4, the reel stands 7, 8
The frictional resistance between the reel stand support shafts 3 and 8 and the reel stand support shafts 3 and 4 is minimized, so that the loss of rotational force generated in the reel stands 7 and 8 can be minimized.

In addition, in the above-mentioned embodiment, the thrust receiving part 20 and the abutting part 22 provided on the cap 10 are
By forming the thrust receiving portion 20 and the abutting portion 22 on the same plane, high precision can be easily maintained. That is, since the molding surfaces of the thrust receiving part 20 and the abutting part 22 of the mold used during molding can be formed on the same plane, processing becomes easy and positioning can be performed with extremely high precision. Then, by abutting the tip of the shaft portion 11 of the reel stand 7 against the abutting portion 22, the mounting accuracy of the reel stand 7 can be improved. Therefore, by simply maintaining sufficient dimensional accuracy from the reel mounting surface of the reel receiver 13 to the tip of the shaft 11, the tape reels 29, 3
0 placement position can be determined with high precision.

[Effect of idea]

As mentioned above, in the present invention, the load in the thrust direction of the reel stand is received by the spherical part of the thrust bearing part of the cap attached to the tip of the reel stand and the reel stand support shaft. The rotational resistance received from the mechanism can be minimized, and the reel stand can always rotate stably.

In addition, the present invention can be installed by simply fitting the reel stand to the reel stand support shaft, making the installation work extremely easy, and since the structure is simple, it can be provided at low cost.

Furthermore, with the present invention, the reel stand can be positioned and installed by simply abutting the cap attached to the reel stand support shaft against the reel stand support shaft. The reel stand can be mounted with accurate positioning.

Therefore, the tape reel of the tape cassette is stably supported at a fixed position, and stable tape running of the magnetic tape is guaranteed.

In the above-described embodiments, an example was shown in which the reel stand device of the present invention was installed in a video tape recorder, but the present invention can be applied to various other reel stand devices.

[Brief explanation of drawings]

1 to 4 show an example in which the reel stand device according to the present invention is applied to a video tape recorder. Figure 2 is a perspective view of the base of the reel stand seen from below, Figure 3 is a partially cutaway perspective view of the cap of the reel stand seen from below, and Figure 4 is a perspective view of the reel stand with a tape cassette attached. FIG. 5 is a longitudinal sectional view of the video tape recorder in this state, and is a schematic perspective view showing an example of a tape cassette for the video tape recorder. FIG. 6 is a cross-sectional view showing the main parts of a tape cassette for a video tape recorder, and FIG. 7 is a longitudinal cross-sectional view of the main parts showing a conventional reel stand device installed in a video tape recorder with the reel engaged. It is. 1...base chassis which is the chassis part, 3,
4... Reel stand support shaft, 7, 8... Reel stand, 1
0,10... Cap, 18... Spherical part, 20
...Thrust receiver.

Claims (1)

[Scope of utility model registration request] The reel stand is rotatably inserted through the reel stand support shaft which has a spherical part at the tip and is planted in the chassis part, and the reel stand support shaft is inserted into the inner surface of the cap that is fitted to the tip of the reel stand. A reel stand device comprising a thrust receiving part that comes into contact with a spherical part.