GB2228358A

GB2228358A - Flywheel for a radio double cassette tape recorder

Info

Publication number: GB2228358A
Application number: GB8903603A
Authority: GB
Inventors: Yen-Nien Lee
Original assignee: NICE YOUNG CO Ltd
Current assignee: NICE YOUNG CO Ltd
Priority date: 1989-02-16
Filing date: 1989-02-16
Publication date: 1990-08-22
Also published as: GB8903603D0

Abstract

There is provided a flywheel for a radio double cassette recorder in which the flywheel for the playing section and the flywheel for the recording section are combined as a single flywheel having two grooves one associated with the playing section and the other associated with the recording section. The flywheel is preferably injection molded of a plastics material. Single flywheel construction obviates the difficulties encountered by producing separate flywheels requiring double storage facilities, more difficult production line control and defects between injection molding machines. <IMAGE>

Description

FLYWHEEL FOR A RADIO DOUBLE CASSETTE TAPE RECORDER This invention relates to a flywheel for a radio double cassette tape recorder.

The e fly wheels of the recording and playing sections of conventional radio double cassette tape recorders are different since the transmission system of a radio double cassette tape recorder comprises a motor and a main shaft. Moreover, there are two flywheel grooves on the main shaft which are used for connection with flywheels by transmission belts. Since there is a specific distance between these two grooves and the transmission is applied by horizontal belts, the vertical spacing between the flywheel grooves will have the same relative spacing.

However, the two flywheels in question are located on the same surface and thereby have equal levels. To accommodate the problem the thickness of the flywheels is arranged to be different.

The thickness of the flywheel for the playing section is thicker than the thickness of the flywheel for the recording section which leads to the following differences between these two flywheels:1. The manufacture of different flywheels. There is no substantial problem during manufacture to control the thickness of a particular flywheel. However, the precision of conventional motors to transmit the flywheels for the recording and playing sections simultaneously is a major problem because the grooves used by the transmission belts must be closely spaced one relative to the other. Moreover, it is essential to accurately predict the tolerances during manufacture since the tape (recorded with a signal) in the playing part must be stopped after the blank tape in the recording part has stopped. It is essential to ensure no defect will arise during synchronous dubbing.When the flywheel is rotated by the same transmission shaft, the diameter of the flywheel groove for the playing section has to be equal or less than the diameter of the flywheel groove for the recording section. The flywheels having a different thickness should be manufactured in different molds during injection molding. The quality of these two flywheels is not easy to control due to the difference of operator, machine, even the time and weather batch. Accordingly, the defect rate is always very high and the mold has to be replaced regularly. If defective parts are used the preformance of a radio/tape recorder will be greatly impaired.

2. Storage and assembly of different flywheels. In manufacture it is necessary to be able to select the different flywheels during assembly and since they cannot be mixed it is necessary to ensure the different flywheels are located separately. If one of the flywheels is in short supply the assembly line must be shut down and causes considerable difficulties in production control.

It is an object of the present invention to provide a flywheel the use of which will enable the above reference disadvantages to be substantially eliminated.

According to the present invention there is provided a flywheel for a radio double cassette tape recorder the flywheel being arranged to be driven from a drive shaft and comprising two grooves one of which is arranged to be used with the playing section of the cassette tape recorder and the other of which is arranged to be associated with the recording section of the cassette tape recorder.

One embodiment of a flywheel according to the present invention which is to be used for a radio double cassette recorder advantageously allows use of the flywheel for both recording and playing sections of the radio double cassette tape recorder. Because the flywheel is manufactured in one mold the tolerances can be controlled more easily and the defect rate is considered to be reduced and avoids disgarding different molds. Since only one flywheel is required for an assembly line the cost of manufacture may be substantially reduced and the assembly is simplified and therfore more easily achieved.

Preferably, the diameter of the said one groove is less than or equal to the diameter of the said other groove. Moreover, each of the two grooves in the flywheel can be provided with e further groove extending inwardly of the flywheel from the bottom of each groove.

Advantageously the invention provides an improved flywheel for radio double cassette tape recorder for which the thickness of the flywheels used in conventional radio double casset tape recorder is improved. A single flywheel with double grooves is described and features two grooves which can match the grooves of conventional flywheels on relative position in the recorder.

The present invention will now be described by way of example with reference to the accompanying drawings, in which: Fig. 1 shows a conventional flywheel in a radio double cassette tape recorder, and Fig. 2 shows a cross-sectional view of a flywheel together with a detailed portion of the drawing illustrating grooves provided in accordance with the present invention.

Referring now to Fig. 1 there is shown a conventional flywheel arrangement in which the flywheels have different thicknesses, such flywheels being utilised in a conventional radio double cassette tape recorder.

More particularly in Fig. 1 a main transmission shaft 1 is connected to a flywheel 2 of a recording section and a flywheel 3 is connected to a playing section by transmission belts (not shown) arranged to extend, respectively, from the shaft 1 to each of the flywheels 2,3.

Because H represents the distance between the two flywheels on the main transmission shaft 1, flywheels 2 and 3 are located on the same base support 4. The thickness of flywheel of the playing section is always thicker along its axial length than the flywheel of the recording section. The e distance H is the space limitation.

Turning to Fig. 2 and in particular part A thereof, there is shown a flywheel having at its outermost peripheral surface two grooves (a) and (b) with groove (a) being the outside groove and groove (b) being the inner groove. Since groove (a) is used for the playing section groove (b) is used for the recording section the diameter (Da) of groove (a) is less than or equal to the diameter (Db) of groove (b). Therefore, to meet the required performance of the conventional flywheels. (Da-Db O).

Whilst the flywheel produced in accordance with this invention can obtain the required performance of the conventional flywheels there are in addition the following advantages.

(1) Only a single mold is required to produce the flywheel and in the event of any mold modification such modification will be to a single mold ensuring a substantial reduction in the production costs of such molds.

(2) Since the complete flywheel is produced by injection molding into a single mold the quality will not be influenced by such factors as different molds, different machines, time and weather etc. Moreover, because the conditions are controlled in a single mold the process is simplified with a resultant reduction in defect rate.

(3) The combined flywheel is easier to store, assemble and simplifies production control because it is not necessary to separate the product into two individual parts during storage and manufacture.

Claims

CLAIMS:

1. A flywheel for a radio double cassette tape recorder the flywheel being arranged to be driven from a drive shaft and comprising two grooves one of which is arranged to be used with the playing section of the cassette tape recorder and the other of which is arranged to be associated with the recording section of the cassette tape recorder.

2. A flywheel as claimed in claim 1, wherein the diameter of the said one groove is less than or equal to the diameter of the said other groove.

3. A flywheel as claimed in claim 1 or claim 2, wherein each of the two grooves in the flywheel is provided with a further groove extending inwardly of the flywheel from the bottom of each groove.

4. A flywheel for a radio double cassette tape recorder substantially as hereinbefore described with reference to, or as illustrated in, Fig. 2 of the accompanying drawings.