KR19990025561U - Head drum assembly - Google Patents

Abstract

The present invention discloses a head drum assembly. Conventional head drum assembly is not only equipped with two bearings in the axial hole of the upper drum, but also because the first and second magnets are mounted in the first and second holders to regulate the axial height of the upper drum, the assembly process is complicated and It is cumbersome to degrade the assembly, there is a problem that the number of assembly parts is increased to increase the production cost. The present invention is mounted so that the upper and lower parts of the metal bearing protrude so that the shaft is supported in the shaft hole of the upper drum, the lower end of the metal bearing is supported by being inserted into the support groove of the lower drum, and the cap is mounted at the upper end of the shaft. To control the axial height and the deviation of the Therefore, the use of metal bearings and caps makes the assembly process easy and simple, improving the assembly of the product, reducing the number of assembly parts, and reducing the production cost of the product. Also, the center hole of the rotor and stator transformer on the outer circumferential surface of the metal bearing This insertion can make the size of the opposing surface large.

Description

Head drum assembly

The present invention relates to a head drum assembly for use in a tape recorder, and more particularly to a head drum assembly in which the assembly process is improved.

In general, a tape recorder such as a video cassette recorder (VCR) or a camcorder (camcorder) is a cassette that travels along a certain traveling path of the traveling system by the rotation of the head drum assembly installed on the top of the deck. To record or play back video and audio signals on tape. In addition, the head drum assembly of the tape recorder adopts a so-called helical scan type in which the video head is rotated obliquely in a state where the tape is rolled and driven.

One example of such a head drum assembly is illustrated in FIG. 1. The head drum assembly 10 includes an upper drum 11 and a lower drum 12 disposed on the shaft 13. It is mounted on the lower part respectively. A bearing housing 11a is formed in the center of the upper drum 11 to have a shaft hole 11b, and an accommodating space 11c is formed in the upper drum 11. The upper drum 11 is mounted on the upper part of the shaft 13 by the support of two bearings 14a and 14b in which the shaft hole 11b is mounted on the upper and lower portions thereof, and the lower drum 12 is located at the center thereof. Shaft hole 12a is press-fitted to the lower part of the shaft 13 and mounted.

In addition, a rotary transformer 15 for transmitting a video signal is mounted in the space between the upper drum 11 and the lower drum 12. The rotary transformer 15 is composed of a rotor transformer 15a attached to the lower surface of the upper drum 11 and a stator transformer 15b attached to the upper surface of the lower drum 12. The rotor and stator transformers 15a and 15b are respectively interposed so as to maintain a constant air gap on their opposite surfaces.

In addition, two or more video heads 16 are assembled on the lower surface of the upper drum 11 so as to correspond to each other, and a drum motor 20 is installed in the accommodation space 11c of the upper drum 11. The drum motor 20 has a first holder 21 assembled at an upper end of the shaft 13, a first magnet 21a mounted on a lower surface of the first holder 21, and a first holder 21. The second holder 22 is mounted so as to be spaced apart from each other at predetermined intervals below, and the second magnet 22a is mounted on the upper surface of the second holder 22. The opposite polarities are magnetized to the first and second magnets 21a and 22a of the first and second holders 21 and 22 to restrict the axial height of the upper drum 11.

On the other hand, the circuit board 23 is mounted on the upper surface of the first holder 21, a stator core 24 is installed on the lower surface of the circuit board 23, and the drive coil 25 is mounted on the stator core 24. ) Is wound. A rotor case 26 is installed outside the stator core 24, a driving magnet 27 is attached to the inner surface of the rotor case 26 in the radial direction of the stator core 24, and the rotor case 26 is attached. ) Is assembled by fastening so as to be rotatable with the upper drum 11.

Therefore, when the magnetic field is formed by the current applied to the drive coil 25 of the stator core 24, the rotor case 26 due to the magnetic force action of the magnetic field of the drive coil 25 and the magnetic field of the drive magnet 27. The upper drum 11 is rotated about the shaft 13 together with the upper drum 11, and the upper drum 11 is rotated to perform recording or reproduction of a video signal on the tape by the action of the video head 16.

However, the head drum assembly 10 as described above is not only mounted with two bearings 14a, 14b in the shaft hole 11b of the upper drum 11, but also regulates the axial height of the upper drum 11. However, since the first and second magnets 21a and 22a are mounted on the first and second holders 21 and 22, the assembling process is complicated and cumbersome, resulting in poor assembly of the product and an increase in the number of assembly parts. There was a problem of raising the production cost. In addition, the configuration of the upper and lower drums 11 and 12 is complicated, and the manufacturing cost of the mold for manufacturing them is increased, and the machining of the upper and lower drums 11 and 12 is difficult, and the rotor and stator cores 15a, There was a problem that the manufacturing of the opposing surface of 15b) was also limited.

The present invention is devised to solve the conventional problems as described above, the object of the present invention is not only to improve the assembly of the product by a simple configuration and structure, but also to produce the product due to the reduction of the number of parts It is to provide a head drum assembly to reduce the unit cost.

1 is a cross-sectional view showing one example of a general head drum assembly,

2 is a cross-sectional view showing a head drum assembly according to the present invention,

Figure 3 is a cross-sectional view showing an assembled state of the head drum assembly according to the present invention.

♣ Explanation of symbols for the main parts of the drawing ♣

30: head drum assembly 31: upper drum

31a: shaft hole 32: lower drum

32a: shaft hole 32c: support groove

33: shaft 34: metal bearing

35: rotary transformer 40: cap

41: body 44: boss

50: drum motor 51: circuit board

In order to achieve the above object, a feature of the present invention is a head drum assembly for performing recording and reproduction of a video signal, comprising: an upper drum having a shaft hole in which a shaft is mounted; A lower drum mounted at a lower portion of the upper drum, having a shaft hole in which a shaft is pressed in the center thereof, and a supporting groove formed at an upper portion of the shaft hole; A metal bearing mounted on the upper and lower parts of the upper drum so as to support the shaft, the lower end being inserted into and supported by the support groove of the lower drum; A rotary transformer comprising a rotor transformer attached to the lower surface of the upper drum and a stator transformer attached to the upper surface of the lower drum; And a cap mounted to the upper end of the shaft and including a cap to regulate the axial height and release of the upper drum.

Hereinafter, one preferred embodiment of a head drum assembly according to the present invention will be described in detail with reference to the accompanying drawings.

2 and 3 are views for explaining the head drum assembly according to the present invention.

2 and 3, the head drum assembly 30 has an upper drum 31 and a lower drum 32 mounted on the upper and lower portions of the shaft 33, respectively. A shaft hole 31a is formed in the center of the upper drum 31, and a flange 31b is protruded from the lower surface of the upper drum 31, and an accommodating space 31c is formed above the upper drum 31. Is formed. The upper and lower portions of the metal bearings 34 are mounted to the shaft holes 31a of the upper drum 31 so as to protrude from each other, and the upper drum is centered about the shaft 33 by the support of the metal bearings 34. 31 is mounted to be freely rotatable. That is, the metal bearing 34 is formed long in a sleeve type and mounted in the shaft hole 31a of the upper drum 31.

A shaft hole 32a is formed at the center of the lower drum 32, and an annular table 32b is formed to protrude concentrically with the shaft hole 32a at the inner bottom of the lower drum 32. A support groove 32c is formed in the upper portion of the shaft hole 32a. The shaft hole 32a of the lower drum 32 is press-fitted to the lower portion of the shaft 33, and the lower end of the metal bearing 34 is inserted into and supported by the support groove 32c of the lower drum 32. Accordingly, the upper end of the metal bearing 34 is regulated at a constant height.

In addition, a rotary transformer 35 for transmitting a video signal in a contactless manner is mounted in the space between the upper drum 31 and the lower drum 32. The rotary transformer 35 is composed of a rotor transformer 36 attached to the flange 31b of the upper drum 31 and a stator transformer 37 attached to the table 32b of the lower drum 32. The rotor and stator transformers 36 and 37 are interposed so as to maintain constant voids on opposite surfaces thereof, and the rotor and stator transformers 36 and 37 are centered holes 36a and 37a fitted to the outer circumferential surface of the metal bearing 34. Has

The center holes 36a and 37a of the rotor and stator transformers 36 and 37 are preferably formed as small as possible in diameter. When the diameters of the center holes 36a and 37a are reduced in this manner, the opposing surfaces of the rotor and stator transformers 36 and 37 are made relatively large in size. Here, the rotor transformer 36 is adhered to and attached to the flange 31b of the upper drum 31, and the stator transformer 37 is adhered to and attached to the table 32b of the lower drum 32.

On the other hand, two or more video heads 38 are assembled on the lower surface of the upper drum 31 so as to correspond to each other, and a cap 40 is mounted at the upper end of the shaft 33. The cap 40 has a shaft hole 42 formed in the center of the body 41, the shaft hole 42 of the cap 40 is mounted to the shaft 33 by pressing. Cap 40 is a flange 43 is formed on the outer peripheral surface of the body (41). The boss 44 protrudes from the lower surface of the flange 43 so as to have a support hole 45 which is connected to the shaft hole 42 and the upper end of the metal bearing 34 in the support groove 45 of the boss 44. Is inserted and supported, whereby the axial height of the upper drum 31 is restricted and the separation of the upper drum 31 is prevented.

In addition, the drum motor 50 is installed in the accommodation space 31c of the upper drum 31. The drum motor 50 is press-fitted to the boss 44 of the cap 40 so that the assembling holes 51a of the circuit board 51 correspond to each other, and the upper surface of the circuit board 51 is cap 40. It is supported by the flange 43 of the will be regulated to a certain height. Here, the flange 43 of the cap 40 and the circuit board 51 may be assembled by tightening screws (not shown). In the drum motor 50, the stator core 52 is installed on the lower surface of the circuit board 51, and the driving coil 53 is wound around the stator core 52. The rotor case 54 is installed outside the stator core 52, the driving magnet 55 is attached to the inner surface of the rotor case 54 in the radial direction of the stator core 52, and the rotor case 54 is upper It is assembled by fastening so as to be rotatable with the drum 31.

Therefore, when the magnetic field is formed by the current applied to the drive coil 53 of the stator core 52, the rotor case 54 due to the magnetic force action of the magnetic field of the drive coil 53 and the magnetic field of the drive magnet 55. The upper drum 31 is rotated by the support of the metal bearing 34 about the shaft 33, and the upper drum 31 is rotated, so that the video signal is applied to the tape by the action of the video head 38. Recording or playback will be performed.

As described above, the present invention has the upper and lower ends of the metal bearing 34 in the state in which the metal bearing 34 is mounted in the shaft hole 31a of the upper drum 31, and the support groove 32c of the lower drum 32 is provided. And the support grooves 45 of the cap 40 are respectively fitted with corresponding pipes, so that the axial height of the upper drum 31 is not only regulated, but the separation of the upper drum 31 is effectively prevented. Accordingly, the use of the metal bearing 34 facilitates and simplifies the assembly process, thereby improving the assembly of the product and reducing the number of assembly parts, thereby reducing the production cost of the product. In short, the present invention simplifies the construction and structure by using the metal bearing 34 and the cap 40, the number of assembly parts is significantly reduced compared to the conventional head drum assembly (10).

In addition, the center holes 36a and 37a of the rotor and the stator transformers 36 and 37 are fitted to the outer circumferential surface of the metal bearing 34 so as to be mounted in the inner space of the upper drum 31 and the lower drum 32. Therefore, the opposing surfaces of the rotor and stator transformers 36 and 37 can be made large. That is, since the diameters of the center holes 36a and 37a can be made small in size corresponding to the outer diameter of the metal bearing 34, the rotor and stator transformers 36 and 37 have the size of the opposing surface of the center hole 36a. , 37a) can be made large in response to the smaller diameter. Therefore, even when the diameter of the head drum assembly is made relatively small, such as a digital video cassette recorder, it can be produced without being limited by the size of the rotary transformer.

On the other hand, the above-described embodiment is merely to describe one preferred embodiment of the present invention, the scope of application of the present invention is not limited to such, and can be changed appropriately within the scope of the same idea. For example, the shape and structure of each component specifically shown in the embodiment of the present invention can be modified.

As described above, the head drum assembly according to the present invention, the use of the metal bearing and the cap, the assembly process is easy and simple to improve the assembling of the product, as well as the number of assembly parts is reduced to reduce the production cost of the product will be. In addition, the center hole of the rotor and the stator transformer is fitted to the outer circumferential surface of the metal bearing, so that the size of the opposing surface can be made large.

Claims (3)

A head drum assembly for performing recording and reproduction of video signals, An upper drum 31 having a shaft hole 31a in which a shaft 33 is mounted in the center thereof; It is mounted to be located below the upper drum 31, the shaft hole 32a is formed in the center of the shaft 33 is pressed, the support groove 32c is formed in the upper portion of the shaft hole (32a) A lower drum 32; The upper and lower portions are respectively mounted to protrude from the shaft hole 31a of the upper drum 31 so that the shaft 33 is supported, and the lower end is inserted into the supporting groove 32c of the lower drum 32 to be supported. A metal bearing 34; A rotary transformer (35) comprising a rotor transformer (36) attached to a lower surface of the upper drum (31) and a stator transformer (37) attached to an upper surface of the lower drum (32); And a cap (40) mounted to the upper end of the shaft (33) to restrict the axial height and disengagement of the upper drum (31). 2. The rotor and stator transformers 36 and 37 of the rotary transformer 35 each have center holes 36a and 37a fitted to the outer circumferential surface of the metal bearing 34 in the center thereof. A head drum assembly. According to claim 1, wherein the cap 40 is formed in the center of the body 41, the shaft hole 42 through which the shaft 33 is pressed, the drum motor 50 on the outer peripheral surface of the body 41 A flange 43 is formed to support the upper surface of the circuit board 51 to be configured, and a boss having a support groove 45 so that the upper end of the metal bearing 34 is fitted to and supported by the lower surface of the flange 43. A head drum assembly, characterized in that 44 is protruded.