US3537631A

US3537631A - Idler roller

Info

Publication number: US3537631A
Application number: US728967A
Authority: US
Inventors: Wesley M Fujii
Original assignee: BELL SOUND STUDIOS Inc
Current assignee: BELL SOUND STUDIOS Inc
Priority date: 1968-05-14
Filing date: 1968-05-14
Publication date: 1970-11-03
Anticipated expiration: 1987-11-03

Description

[56] References Cited UNITED STATES PATENTS 3,l32,787 5/l964 Rayfield 226/194X Primary Examiner-Allen N. Knowles Attorney Yuter and Fields ABSTRACT: An idler roller for use in a tape recorder and the like comprising a shaft adapted to be received in the tape recorder. A mounting member is rotatably received on the shaft and a roller assembly is removably and concentrically mounted on the mounting member. The mounting member is provided with a first surface and the roller assembly is provided with a second surface adapted to engage the first surface. Retaining means is provided to force the first and second surfaces into intimate contact with each other so that the mounting member and the roller assembly rotate as a unit.

Wesley M. Fujii Menlo Park, (California [21 Appl. No. 728-,967

May 14, I968 [45] Patented Nov. 3, I970 Bell Sound Studios, Inc. New York, New York a corporation of New York 226/ 191,. 226/ I94; 29/130!- ...'B65h 17/20 2261190. l9l, l94;29/l I7, I32, I30

16 Claims, 2 Drawing Figs.

52 Int.

Field United States Patent [72] Inventor [22] Filed [73] Assignee [$4] IDLERROLLER' H. hi

Patented Nov. 3, 1970 INVENTOR.

Wesley M. Fujii AT T 0 RN EYS IDLER ROLLER This invention relates generally to an idler roller for a tape recorder and the like and, more particularly, pertains to an idler roller having a replaceable frictional surface.

Conventionally, an .idler roller in a tape recorder bears against the tape as the tapeis transported from the feed to the takeup reel or from the takeup reel to the feed reel. The idler roller or roller may be utilized to maintain the tape in a prescribed path or it may be used as a pinch roller to pinch the tape between the capstan and the roller to cause the tape to I advance or rewind. Normally, the roller includes a bearing on which is mounted a member having an outer surface having a relatively high coefficient of friction, such as rubber or the like. Accordingly, the linear movement of the tape part! the roller is translated to a rotational movement ofthe roller.

t In practice, it has been found that the bearings of tire pinch roller or idler roller lusts the life of the tape recorder but the frictional tape engaging surface is subject to normal wear and tear and must be replaced frequently. Presently, however, the roller is manufactured as a unitary structure. Hence, when the frictional surface becomes worn or damaged, the entire unit must be replaced. This replacement represents an unnecessary high cost to the customer since the bearing assembly is a major portion ofthe cost of the unit.

Accordingly. an object of the present invention is to provide a roller having a removable frictional surface which may be replaced when the surface becomes worn or damaged.

Another object of the present invention is to provide a roller which is simple to fabricate and economic to manufacture A further object and feature of the present invention resides in the novel details of construction which provides a roller of the type described wherein a portion carrying the frictional surface is automatically centered and drivingly connected to a rotatable member when it is mounted thereon.

Another object of the present invention is to provide a roller which is compatible for use in existing tape recorders.

Accordingly, an idler roller constructed in accordance with the present invention includes a shaft adapted to be mounted on a tape recorder. A member is rotatably mounted on the shaft and is provided with a first surface. A roller assembly is removably mounted on said member. The roller assembly includes an inner sectionhaving a second surface adapted to engage the first surface of-said member, and an outer section on said inner section adapted to engage a tape. Retaining means is also provided which engages said member and said rollerassembly'for forcing said first and second surfaces into intimate and driving engagement with each other.

Other features and advantages of the present invention will become more apparent from a consideration of the following detailed description when taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of atape recorder utilizing an idler roller constructed in accordance with the present invention;

FIG. 2 is a vertical sectional view ofthe idler roller shown in FIG. I; and

FIG. 3 is a vertical sectional view of a modified embodiment of a roller constructed according to the invention.

While an idler roller of the present invention may be utilized in any piece of equipment which requires a device to translate the linear motion of a tape or the like to a circular motion, the roller of the present invention will be described in conjunction with the operation of a conventional tape recorder and, more particularly, as a pinch roller. However, it is emphasized that this is for illustrative purposes only and is not be interpreted as being a limitation of the present invention.

Accordingly, FIG. 1 illustrates a tape'recorder designated generally by the reference numeral which utilizes an idler or pinch roller 12 constructed in accordance with the present invention. The tape recorder 10 includes a base 14 having an upper surface 16 which supports a feed reel 18 and a takeup reel 20. The tape 22 extends from the feed reel 18, through a recording housing designated generally by the reference hameral 24 to the takeup reel 20. conventionally, the recording housing 24 is an enclosed housing. However, in the interest of clarity the housing 24 is illustrated with the top portion of the housing removed.

Received within the housing 24 is an erase head (not shown) and a record-playbaek head 26. A rotating capstan 28 is in spaced relationship to the head 26 and is adapted to rotate at a substantially uniform speed when the recorder is either recording or playing back a prerecorded tape. The roller 12 is conventionally mounted on a movable arm (not shown) which arm is adapted to move the roller 12 so that the tape is pinched between the roller 12 and the capstan 28. Thus, the rotational motion of the capstan 28 is transmitted to the tape 22 thereby causing the tape 22 to move past the recording head 26 at a substantially uniform speed.

In operation, during a recording or playback cycle of the tape recorder 10, a motor within the base 14 causes the takeup reel 20and the capstan 28 to rotate. The tape 22, which is pinched between the roller 12 and the capstan 28 moves past the record or playback head 26 thereby causing the recording of information on the tape 22 or the playback of information through an appropriate speaker (not shown), as the case may be.

In the past, as noted above, the roller was manufactured as a unitary structure which included an outer covering having a high coefficient of friction mounted on a hall or sleeve bear ing. Hence, when the outer covering was worn or damaged the whole structure had to be replaced. However, in accordance with the invention, only the element carrying the frictional surface may be replaced thereby producing a substantial saving in cost.

More specifically, as shown in FIG. 2, the roller 12 includes a shaft 30 having a lower portion 32 ofenlarged diameter and an upper portion 34 of reduced diameter which define a shoulder 36 therebetween. Received on the upper reduced diameter portion 34 ofthe shaft in a slip fit is a ball bearing 38, the inner race of whichabuts the shoulder 36. The ball bearing is maintained in place on the shaft by a washer 40 which receives the upper end of the shaft therethrough and a retaining, ring 42 which is received in a groove 44 adjacent the top end of the shaft.

Mounted on the ballbearing 38 is an inner or mounting member designated generally by the reference numeral 46, which is adapted to mount a roller assembly 48. The mounting member 46 is circular and is provided with a central through bore 50. Received in the central through bore 50 in a slip fit is the ball bearing 38. Provided in the walls defining the through bore 50 are axially spaced annular grooves 52. Received within the grooves 52 and corresponding grooves in the ball bearing 38 are spring biased retaining rings 54 which are biased outwardly into. contact with the ends of the walls defining the grooves 52. As shown in FIG. 2, the inner or mounting member 46 is concentric to the axis of the shaft 30. It should be noted that a sleeve hearing may be utilized in place of the ball bearing 38 and a press fit may be provided between the bearing and the member 46.

The inner member 46 further includes an upper portion 56 which extends upwardly beyond the top end of the shaft 30. The upper portion 56 is externally threaded at 58. The outer peripheral wall 60 of the inner member 46 is tapered downwardly and outwardly from the axis ofthe member.

As noted hereinabove, the inner member 46 is adapted to mount the roller assembly 4B/Specifically, the roller assembly 48 includes a circular inner section 62 having a central through bore 64. The wall defining the central through bore 64 is tapered complementary to the taper of the wall 60. That is, the wall defining the bore 64 is tapered downwardly and outwardly so that the wall defining the bore 64 engages the peripheral wall 60 ofthe inner member 46 and may be forced into intimate contact therewith, in the manner noted below. In practice, the aforementioned tapers vary between l4-l6. Fixedly received on the outer peripheral wall of the inner section 62 is a ring or outer section 68 of resilient material having a relatively high coefficient of friction. in practice, the ring 68 may comprise neoprene or a similar material. The outer surface of the ring 68 is adapted to engage the tape 22.

Received on the threaded upper portion 56 of the inner member 46 is a cap 70. More specifically, the cap 70 is provided with an internally threaded portion 72 which is adapted to engage the threads 58 on the member 46. The cap 70 includes an under or bearing surface 74 which extends radially outwardly from the axis of the shaft 30 and is adapted to bear on the upper surface ofthe roller assembly 4d.

The lower enlarged diameter portion 32 of the shaft 30 is provided with a flat surface 76 which is adapted to provide a bearing surface for it set screw 78 in a holding member indicated generally by the dashed lines 80. The holding member 80 may comprise a portion of the tape recorder 10.

la operation, the shaft 30 is inserted into the holding member 80 and the set screw 78 is tightened against the bearing surface 76 of the shaft so that the shaft is fixedly mounted on the tape recorder 10. The roller assembly 48 is then placed over the inner member46 until the surface defining the bore 64 engages the complementary tapered surface 60 ofthe inner member The cap 70 is then threaded onto the upper portion 56 of the inner member 46 until the bearing surface 74 engages the upper surface of the roller assembly 48. It is to be noted that the height of the roller assembly 48 is slightly in excess of the height of the wall 60 so that the bearing surface 74 of the cap 70 does not contact the main body portion of the inner or mounting member 46. The cap 70 is then tightened on the inner member 46 thereby forcing the roller assembly 48 downwardly. Since the surface 60 and the wall of the bore 64 are tapered the downward force exerted by the cap 70 will produce a radial component which forces the roller assembly 48 into a driving connection with the inner member 46. Moreover, this complementary taper automatically centers the roller assembly 48 so that the roller assembly 48 is concentric to the axis of the shaft 30 and, further, centers the roller assembly in the vertical plane.

As the tape 22 moves past the ring 68 the coefficient of friction therebetween is such that the linear movement ofthe tape 22 will cause the roller assembly 48 to rotate. The slip fits between the ball bearing 38, the shaft 30 and the inner member 46 are such that the roller assembly 48 and the inner member 46, which are now locked together, will rotate on the ball bearing 38.

When the ring 68 is worn through normal use or is damaged and must be replaced, the cap 70 is removed and the roller assembly 48 is lifted upwardly to separate the roller assembly from the inner member 46. A new roller assembly 48 is dropped into place and the cap 70 is retightened thereby to provide a new surface for the tape to engage. It should be noted that the taper is of sufficient magnitude to prevent selflockirrg between the elements.

Accordingly, a roller has been described which is simple in construction and economic to utilize since only the roller assembly 48 is replaced when the ring 68 is worn or damaged.

A modified embodiment of a roller constructed according I to the invention is shown in FIG. 3 and designated generally by the reference numeral112. The roller 112 is similar in construction to the roller 12 and identical elements are designated by the same reference numerals. Additionally only the differences between

rollers

12 and 112 will be described.

Accordingly, the roller 112 includes a mounting member 146 which is mounted on the ball bearing 38 in the same manner as the member46. The member 146 is provided with a radially extending circumferential flange 147 adjacent the bottom edge thereof. Received on the mounting member 146, in a sliding fit with the outer wall 160 thereof, is a roller assembly 148. More particularly the roller assembly 148 includes an inner section 162 having a through bore defined by the wall 164. The walls 160 and 164 are concentric with the axis ofthe shaft 30 and, as noted above, engage each other in a sliding fit. The ring 68 of resilient material of high coefficient offriction is mounted on theinner section 162.

As shown in FIG. 3, the bottom edge of the inner section 162 of roller assembly 148 is adapted to engage the flange 147. The cap is adapted to engage threadedly the portion 156 of the mounting member 146 and bear against the upper surface thereof to force the inner section 162 downwardly into intimate engagement with the flange 147. Thus, the roller assembly148 and the mounting member 146 rotate as a unit.

in operation, after the ring 68 becomes worn or damaged, the cap 70 is removed and the roller assembly 148 is moved upwardly thereby separating the roller assembly and the mounting member. The new roller assembly then is dropped into place and the cap 70 is replaced. Accordingly, the roller 112 likewise provides a replaceable roller assembly which is self-centering.

While a preferred embodiment of the invention has been shown and described herein it will become obvious that numerous omissions, changes and additions may be made in such embodiment without departing from the spirit and scope of the present invention.

lclaim:

1. A roller for use in a tape recorder and the like comprising a shaft adapted to bemounted on the tape recorder; a member having a tapered outer surface; rotating means for rotatably mounting said member on said shaft; a roller assembly removably mounted on said member; said roller assembly including an inner section having an inner wall provided with a taper complementary to said tapered surface of said member and in engagement therewith, and an outer section on said inner section adapted to engage a tape; and retaining means engaging said member and said roller assembly for forcing said tapered surfaces into intimate and driving engagement.

2. A roller as in claim 1, in which said member is circular, and the outer surface of said member tapers outwardly and downwardly.

3. A roller as in claim 2, in which said inner wall is circular, and said inner wall tapers outwardly and downwardly.

4. A roller as in claim 1, in which said outer section of said roller assembly comprises a ring of material having a high coefficient of friction.

5. A roller as in claim 4, in which said ring of material is fabricated from neoprene.

6. A roller as in claim 1, in which said member includes a central threaded portion projecting upwardly above said outer surface, and said retaining means comprises a radial cap threadedly engaging said central portion, said cap having a bearing surface adapted tobear against said roller assembly to force said roller assembly into intimate engagement with said member. I

7. A roller as in claim 1, in which said shaft includes an upper portion of reduced diameter and a lower portion defining a shoulder therebetween, said rotating means including a ball bearing assembly mounted on said shaft and abutting said shoulder, said member having a central through bore receiving said ball bearing assembly therein to rotatably connect said member with said shaft, and at least one retaining ring connecting together said ball bearing assembly and said member.

8. A roller as in claim 1, in which said shaft includes a substantially flat face adapted to provide a bearing surface for a set screw.

9. A roller for use in a tape recorder and the like comprising a shaft adapted to be mounted on a tape recorder; a mounting member including a first surface; rotation means for rotatably mounting said mounting member on said shaft; a roller assembly removably mounted on said mounting member; said roller assembly including an inner section having a second surface adapted to engage said first surface, and an outer section on said inner section adapted to engage a tape; and retaining means in contact with said mounting member and said roller assembly for forcing said first and second surfaces into intimate and driving engagement with each other.

10. A roller as in claim 9, in which said first surface comprises a radially extending flange on said mounting member roller assembly.

H. A roller as in claim 10, in which said second surface said shoulder, said member being a central through bore receiving said ball bearing assembly therein to rotatably concomprises the lower edge of saidinner section, and said retaining means includes a cap threadedly connected to said mounting member and having a bearing surface in engagement with said roller assembly.

12. A roller as in claim 9, in which said first surface includes the outer wall of said mounting member. said outer wall having a preselected taper, said inner section of said roller as sembly having a bore defined by an inner wall adapted to receive said mounting member therein, said second surface comprising said inner wall, said inner wall being provided with a taper complementary to said preselected taper.

13. A roller as in claim 12, in which said mounting member is circular, and the outer wall of said member tapers outwardly and downwardly.

14. A roller as in claim 13, in which said shaft includes an upper portion of reduced'diameter and a lower portion defin ing a ballbearing assembly mounted on said shaft and abutting nect said member with said shaft, and at least one retaining ring connecting together said ball bearing assembly and said member.

15. A removable roller assembly for a roller of the type including a shaft which rotatably supports a mounting member, said roller assembly comprising an inner member having a central bore adapted to receive the mounting member therein, and an outer section concentrically located on said inner section and having a relatively high coefficient of friction and being adapted to engage a tape, said inner section being provided with a surface (adapted) sized to detachably engage in intimate contact the mounting member so that said roller assembly and said mounting member rotate as a unitary struc' ture.

16. A roller assembly as in claim 15, in which said surface tapers downwardly and outwardly to engage a complementary tapered surface ofthe mounting member.