KR0124472Y1 - Lubricating apparatus of vcr head drum assembly - Google Patents

Abstract

The present invention provides a lubrication device for a head drum assembly of V-AL which is easy to manufacture and inexpensive, can effectively support an axial load, and can maintain good lubrication characteristics for a long time without replenishing oil. The lubrication device of the present invention has a lower drum 30 which is held in a fixed state, a main shaft 32 which is assembled to penetrate the lower drum, and is driven by a motor, and is fixed to an upper end of the main shaft and rotates together with the main shaft In the head drum assembly of V-C, comprising an upper drum (34) having a video head for recording and playing a video signal, the shaft hole (52) is formed integrally with the lower drum and has a main shaft inserted therethrough. ), An annular bearing seat 54 provided at both ends of the shaft hole, and at least one axial recess extending axially along the bearing seat and opening radially inward over its entire length, through the bearing seat. A bearing housing 50 having a 56 and a bearing seat of the bearing housing so as to rotatably support the main shaft in a radial and axial direction, the axial direction A rectangular ring-shaped oil supply groove 59 is formed along the outer circumferential surface, the inner circumferential surface, the upper surface and the lower surface of the position corresponding to the recess, and a series of cutout grooves 60 and the axial load supporting surface 62 are formed on the upper surface. It consists of an alternately arranged journal bearing 58 and a lubrication pad 72 that is press-fitted into the axial recess of the bearing housing and continuously supplies oil to its inner circumferential surface through the lubrication groove of the journal bearing. do.

Description

Lubricator for head drum assembly

FIG. 1 is a longitudinal sectional view of a conventional head drum assembly employing ball bearings designed to simultaneously support radial and axial loads of the main shaft.

2 is a longitudinal sectional view of the head drum assembly to which the lubrication device according to the present invention is applied.

3 is a cross-sectional view taken along the line III-III of FIG.

Figure 4 is a perspective view showing a detailed structure of the lubrication apparatus according to the present invention, a view showing a cut portion of the bearing housing and journal bearing.

5 is a partially enlarged view showing the spacer ring axially supported and rotated by the journal bearing.

* Explanation of symbols for main parts of the drawings

30: lower drum 32: spindle

34: upper drum 42: electric motor

50: bearing housing 58: journal bearing

72: oil supply pad

The present invention relates to a head drum assembly of BC-AL, and more particularly to a head drum assembly of BC-AL for lubricating the main shaft of the head drum assembly and supporting a load acting on the lower drum according to the rotation of the main shaft. It relates to a lubrication device for.

As is known, a typical V-Cal has a deck or main chassis, a traveling system installed on the deck to take out the tape from the cassette and moves it along a predetermined path, and a tape disposed at a suitable location of the traveling system and moving. It is equipped with a head drum assembly for recording signals to and reproducing signals from tape. In particular, the head drum assembly must directly maintain a high level of reliability and stability since it directly participates in recording and reproducing a signal, and should generate little vibration or noise even after repeated use for a long time. In particular, vibration may cause cross talk, which may have a detrimental effect on image quality. Therefore, it is necessary to strictly control the vibration.

In view of this, a head drum assembly as illustrated in FIG. 1 has been developed and widely used in the related art. The head drum assembly includes a lower drum 10 fixed to a deck not shown in the drawings, a main shaft 12 assembled through the lower drum 10, and a main shaft fixed to an upper end of the main shaft 12. The upper drum 14 rotates relative to the lower drum 10 and the electric motor 16 for inducing the rotational movement on the main shaft 12 and the upper drum 14 together with the reference numeral 12. And, on the bottom of the upper drum 14, for example, two head bases 18 are attached so that they are height-adjustable at intervals of 180 [deg.] By screws or the like, each head base 18 having its radial direction. At the outer end, a video head 19 for magnetically recording or reproducing a video signal is provided. In addition, since the rotary transformer 20 is installed between the upper drum 14 and the lower drum 10 so as to transmit a signal in a contactless manner, an image signal supplied to or output from the video head is generated. You can give and receive without. On the other hand, the electric motor 16 is composed of a stator 22 attached to the lower drum 10 and a rotor 24 fixed to the main shaft 12 to rotate the stator 22, the rotor 24 Rotates at high speed with the main shaft 12 and the upper drum 14 as current is supplied to the stator 22, causing the video head 19 to scan the signal tracks of the tape in turn.

In the head drum assembly having the above-described configuration, the main shaft 12 rotates at a high speed to generate radial loads and axial loads. A pair of ball bearings 26 are installed between the drums 10. Each ball bearing 26 has an inner ring 26a and an outer ring 26b, which are fixed axially by the fixing ring 28, while the inner ring 26a is adapted to rotate with the main shaft 12, The outer ring 26b is seated on the stepped portion of the lower drum 10 and maintained in a fixed state. By the way, it is true that the ball bearing 26 has the advantage of excellent lubrication characteristics and load bearing ability, but since the price is relatively expensive and the tolerance management is difficult, the appearance of a lubrication device that can replace this is desired. Therefore, in recent years, a journal bearing type lubrication device for lubricating a main shaft using a journal bearing having a so-called herringbone groove formed on its inner circumferential surface has been put to practical use. However, according to such a lubrication device, it is not easy to process the herringbone groove on the inner circumferential surface of the journal bearing, and if oil leaks out of the bearing during filling and using the herringbone groove, it can be returned to the inside of the bearing. As a result, there is a drawback that the lubrication characteristics of journal bearings are gradually degraded due to the exhaustion of oil. Furthermore, since the end surface of the journal bearing has a simple flat surface, it is difficult to supply lubricating oil and thus it is not suitable to support the axial load, and in order to solve this problem, an additional axial load supporting structure is additionally installed. It should, however, also suffer from a defect that makes it difficult to adjust the height of the upper drum.

The present invention has been made to solve the problems of the prior art as described above, its purpose is to manufacture a low-cost, low lubrication characteristics can be maintained for a long time, and VDL can effectively support the axial load It is to provide a lubrication device for a head drum assembly.

The object of the present invention is a lower drum which is held in a fixed state, a main shaft assembled through the lower drum, and driven by a motor, and fixed to the upper end of the main shaft to rotate together with the main shaft, the image signal In the head drum assembly of V-C, consisting of an upper drum having a video head for recording and reproducing, an integrally formed with the lower drum, a shaft hole through which a main shaft is inserted, and an annular shape provided at both ends of the shaft hole. A bearing housing having a bearing seat and at least one axial recess extending axially along the bearing seat and radially inwardly open over its entire length, the bearing seat having a bearing seat therein; The main shaft is rotatably supported in the radial and axial directions, and corresponds to the axial recess. The journal bearing is formed along the outer circumferential surface, the inner circumferential surface, the upper surface and the lower surface of the position, and the upper surface is a journal bearing having a series of notch grooves and axial load supporting surfaces are alternately arranged; A V-AL including a lubrication pad press-fitted into the axial recess of the housing and continuously supplying oil to the inner circumferential surface through the lubrication groove of the journal bearing can be achieved by the lubrication device for the head drum assembly.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 2 to 5 of the accompanying drawings.

As shown in FIG. 2, the head drum assembly of V-Cal to which the lubrication device of the present invention is applied has a lower drum 30 which is fixedly inclined at a predetermined angle to a deck not shown in the drawing. The main shaft 32 penetrates and is assembled to the lower drum 30. The upper drum 34 is fixed to the upper end of the main shaft 32 to rotate relative to the lower drum 30 together with the main shaft 32.

On the bottom of the upper drum 34, for example, two head bases 36 are attached to the height adjustable by 180 degrees at screw intervals, each head base 36 having its radial direction. A video head 37 for magnetically recording or reproducing a video signal is provided at the outer end. In addition, since the rotary transformer 40 for transmitting a signal in a contactless manner is installed between the upper drum 34 and the lower drum 30, an image signal supplied to or output from the video head 37 is output. It can send and receive without generating noise.

An electric motor 42 is used to rotate the main shaft 32 and the upper drum 34 with respect to the lower drum 30. The electric motor 42 is composed of a stator 44 fixedly attached to the lower drum 30, and a rotor 46 fixedly installed on the main shaft 32 and surrounding the stator 44. The rotor 46 rotates at high speed with the main shaft 32 and the upper drum 34 as current is supplied to the stator 44, causing the video head 37 to scan the signal tracks of the tape in turn.

The lower drum 30 has a bearing housing 50 or a hub formed integrally therewith, the bearing housing 50 having a main shaft 32, as shown most clearly in FIGS. 3 and 4. ) Is inserted through the shaft hole 52, the annular bearing seat 54 provided at both ends of the shaft hole 52, and extends axially along the bearing seat 54 and radially inward over the entire length. And a pair of axial recesses 56 open through and through the bearing seat 54. The bearing seat 54 is formed between the end surface of the bearing housing 50 and the inner step portion 54a and has a diameter slightly larger than that of the shaft hole 52. Preferably, the axial recesses 56 are arranged along the inner circumferential surface of the bearing seat 54 at equal intervals, that is, at intervals of 180 degrees. In addition, the number and arrangement intervals of the axial recesses 56 are not limited to those shown in the drawings, and may be appropriately changed as necessary.

The journal bearing 58 is forcibly fitted to the bearing seat 54 to support the spindle 32 rotatably and to lubricate the spindle 32. The journal bearing 58 is preferably manufactured by sintering an alloy powder containing copper as a main component, and in order to allow oil to penetrate well, the journal bearing 58 must have a porosity that does not adversely affect the load capacity. do. The journal bearing 58 has a rectangular annular lubrication groove 59 continuously formed along the outer circumferential surface, the inner circumferential surface, the upper surface and the lower surface of the position corresponding to the axial recess 56.

In addition, the journal bearing 58 is formed between a series of cutout grooves 60 formed at substantially equal intervals on the upper surface thereof and the cutout grooves 60 as shown in FIGS. 4 and 5. It has an axial load bearing surface 62 positioned thereon. The cutout groove 60 is defined by the vertical surface 60a located in front and the inclined surface 60b located in the rear when judged based on FIG. The inclined surface 60b has a gentle inclination angle and gradually increases toward the rear, and eventually becomes the same height as the axial load supporting surface 62. By making the upper surface of the journal bearing 58 in such a shape, not only the supporting ability of the axial load can be improved, but also the frictional resistance due to the rotation of the upper drum 34 can be reduced.

Referring again to FIG. 2, a spacer ring 64 is inserted between the upper drum 34 and the upper surface of the journal bearing 58, and the spacer ring 64 is connected to the upper drum 34 by a screw 66. It can be seen that it is fixed at. Since the spacer ring 64 moves in the axial direction as the screw 66 is loosened or tightened, the height of the upper drum 34 with respect to the lower drum 30 may be arbitrarily adjusted. The spacer ring 68 is also attached to the stator 46 of the electric motor 42 so that the height can be adjusted by the screw 70. Since each of the spacer rings 64 and 68 rotates in frictional contact with the journal bearing 58 to support the axial load of the upper drum 34, it is preferable to manufacture a bushing having good lubrication characteristics. .

On the other hand, the lubrication pad 72 containing a large amount of oil is pressed into the axial recess 56 of the bearing housing 50. The lubrication pad 72 is for continuously supplying oil to the inner circumferential surface of the journal bearing 58 and the axial load supporting surface 62, and is a soft material having good oil absorption, for example, cotton or sponge. It is manufactured by molding the back into a rod shape. When the lubrication pad 72 is inserted into the axial recess 56, the radially inner surface of the lubrication pad 72 comes into contact with the outer circumferential surface of the journal bearing 58, and thus the lubrication pad 72 is provided. The oil contained in is supplied to each part through the oil supply groove 59 of the journal bearing 58 by the capillary phenomenon to prevent the lubrication characteristics from being weakened.

As described in detail above, according to the lubrication device for the head drum assembly of the present invention, not only can the lubrication of the main shaft using a journal bearing which is easy to manufacture and inexpensive, but also effectively supports the axial load of the main shaft. In addition, it is possible to obtain an industrially useful effect that it is possible to maintain a good lubrication property of the bearing for a long time without replenishing oil.

Claims (5)

A lower drum 30 which is held in a fixed state, a main shaft 32 which is assembled to penetrate through the lower drum, and which is driven by a motor, and which is fixed to an upper end of the main shaft and rotates together with the main shaft, In the head drum assembly of V-Cal consisting of an upper drum (34) having a video head for recording and playback, formed integrally with the lower drum, the shaft hole (52) through which the main shaft is inserted, both ends of the shaft hole An annular bearing seat 54 provided in the at least one axial recess 56 extending axially along the bearing seat and opening radially inward over its entire length, the bearing seat 54 being in contact with the bearing seat; A bearing housing 50, which is fitted to the bearing seat of the bearing housing to rotatably support the main shaft in the radial and axial directions, and corresponds to the axial recess. Square ring-shaped oil supply grooves 59 are formed along the outer circumferential surface, the inner circumferential surface, the upper and lower surfaces of the teeth, and a series of cutout grooves 60 and axial load supporting surfaces 62 are alternately arranged on the upper surface. V-Head head drum including a journal bearing 58 and an oil supply pad 72 press-fitted into an axial recess of the bearing housing to continuously supply oil to an inner circumferential surface through an oil supply groove of the journal bearing. Lubricator for assembly. 2. The lubrication device for a head drum assembly of V-Cal according to claim 1, wherein the journal bearing (58) is sintered with an alloy powder containing copper as a main component. 3. The lubrication apparatus for a head drum assembly of V-Cal according to claim 2, wherein the oil supply pad (72) is made of a soft rod-like material capable of absorbing oil. V according to any one of claims 1 to 3, wherein the cutout groove (60) of the journal bearing (58) is defined by a front vertical surface (60a) and a rear inclined surface (60b). Lubricator for head drum assembly. 4. The bearing according to any one of claims 1 to 3, wherein said friction bearing is disposed between said journal bearing (58) and said upper drum (34) and in axial load bearing surface (62) of said journal bearing (58). Lubricating device for the head drum assembly of V-SI further comprising a spacer ring (64) to rotate with the upper drum (34).