JPS6020187Y2 - Torque measuring device for cassette tape recorder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an improved device for measuring torque in the rewind and fast forward modes of a cassette tape recorder.

First, prior to explaining the present invention, this type of measuring device related to the applicant's earlier application will be briefly described.

In Fig. 1, numeral 1 indicates the entire rewinding and fast-forwarding torque measuring device, which has the same external shape as a compact cassette and is designed to be installed in a tape recorder, but in the case shown, the upper half is shown. Remove to show the arrangement of internal elements.

That is, the upper half and the lower half, which are combined into a cassette, are made of a transparent resin material such as polystyrene, and the inside can be seen through the surface of the upper half to see the meter units on the feeding side and winding side described below. It is designed to read the torque display scale.

In the figure, 3 is the lower half [see Figure 3 for the upper half 2],
4 is the central opening on the front side, 5a, 5b and 6at6b
are openings and small windows in symmetrical positions, 7a, 7b and 8a
, 8b indicates a capstan insertion hole and a positioning hole, which are exactly the same as those of an ordinary compact cassette, but there is no magnetic tape.

In other words, this torque measuring device is mounted on a compact cassette.
The structure is such that the lower half is repurposed and the two are combined, and meter units are housed on the feeding side and winding side, respectively.

9A and 9B indicate meter units disposed on the feeding side and the winding side in the cassette, and these meter units are based on the invention of the present applicant's earlier application (for example, Utility Model Application No. 53-418
No. 34, Utility Model Application No. 115845 and Utility Model Application No. 115845 and Utility Model Application No. 115845
No. 118111 and others), but in short, this is a torque meter with a spring-balanced structure that incorporates a spiral spring, and in both cases, the inner ring 1
Radial by 0a, 10b and outer rings 11a, llb
The structure is similar to a ball bearing, and the center of each inner ring 10avlOb has a retaining hole 2 for inserting the reel shaft on the payout side and take-up side of the tape recorder, respectively.
The inner ring 10a is elastically biased counterclockwise with respect to the outer ring 11a, and the inner ring 10b is elastically biased clockwise with respect to the outer ring 11b.

For example, springs 13 are connected to both outer rings 11a and llb at three equally divided angles on the outer periphery, and the outer ends of these springs 13 are respectively latched to bottles or the like in the lower half 3.

In other words, the outer rings 11a and llb are set to be prevented from rotating by such means, and when the torque measuring device 1 is attached to a tape recorder and set to rewind mode or fast forward mode, the torque of the feed reel shaft or take-up reel shaft can be adjusted. Correspondingly, the inner ring 10a of the meter unit 9A rotates clockwise, and the inner ring 10b of the meter unit 9B rotates counterclockwise, so there is a gap between the inner rings 10a, 10b and the outer rings 11a, llb surrounding them. resulting in a relative angular deviation difference.

Therefore, in the illustrated example, indicators 14 are attached to the surfaces of the inner rings 10a and 10b, and torque scales 15 are displayed on the surfaces of the outer rings 11a and 11b, so that the torque in rewind mode and fast forward mode can be read. ing.

By the way, the inventor of the present invention has carried out numerous measurements using the torque measuring device as described above, and has come to the conclusion that such a device is inevitably subject to slight errors in each measurement.

That is, one of the reasons for this is that the above-mentioned measuring device uses a so-called fixed outer ring method, and problems with this method include the relative positional relationship of the inner ring, outer ring, and spiral spring, and the alignment of the reel shaft. This is because the initial conditions are not constant depending on the state, etc., and the operation during measurement is a static measurement with the outer ring fixed.

It is also known that a normal torque meter is used to measure the torque of the reel shaft, but this type of measurement has large variations due to individual differences, so it is almost impossible to find an accurate torque value. close.

The purpose of the present invention is to propose a new and rational torque measuring device that can improve the problems mentioned above.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3. FIG. 2 is a plan view showing one example, and like FIG. 1, the upper half is removed and the internal elements are shown. Each part of the lower half 3 is given the same reference numerals as in FIG.

In the figure, 16A and 16B are meter units 17a and 17b arranged on the feeding side and winding side in the cassette.
18a and 18b are the respective inner rings, and 18a and 18b are the respective outer rings.Both meter units 16A and 16B have a spring-balanced bearing structure, which is the same as before. 18a
, 18b, the same index 19 and torque scale 20 as in the previous example.
As shown in the figure, these are marked with .

By the way, in the present invention, each meter unit 16A,
The outer rings 18a and 18b of 19B are hollow spur gears,
These are rotated at low speed around inner rings 17a and 17b, respectively.

That is, in the illustrated case, both outer rings 18 of the spur gear are aligned on a common axis passing through the centers of meter units 16A and 16B
A driving pinion 21 is provided which meshes with the outer rings 18a and 18b, and this pinion 21 drives both outer rings 18a and 18b.
The central shaft 22, which is integral with the pinion 21, is rotatably supported by the upper half 2 and the lower half 3, one of which protrudes by a length equal to the upper surface of the upper half 2, the upper part of which will be described later. Specifically, the motor shaft has a mating end (for example, a planed shape) for the joint of the reduced drive shaft.

In addition, in this example, in order to maintain the respective gear outer rings 18a and 18b of the meter units 16A and 16B at a predetermined distance between their axes, the gear outer rings are placed at two positions equidistant from the pinion 21 mentioned above. It has a structure in which a positioning pinion 23 that meshes and is rotatable is provided.

Note that 24 is a reel shaft engagement hole of the inner rings 17a and 17b.

As is clear from the above, the present invention is applicable to the inner rings 17a and 17b of the meter units 16A and 16B, which are engaged with the reel shafts on both sides, in the rewind mode or fast forward mode of the tape recorder. While rotating the outer ring of the gear in the same direction as the inner ring at low speed, a relative angular deviation difference is created between the two, and the load scale of the spring balance is eventually read as a torque measurement value. Since this is a dynamic measurement as opposed to the static measurement in the previous example, it goes without saying that the discrepancy in the initial conditions as mentioned above can be sufficiently corrected, and the measured value always matches the rewinding torque or fast-forwarding torque. It will be possible to punish them.

FIG. 3 is a perspective view showing an example of means for driving the main driving pinion 21 (FIG. 2) of the torque measuring device 1, in which 25 is a DC motor, and 26 is a deceleration device integrated with this motor, such as a planetary gear mechanism. part, 27 is its output shaft (drive shaft),
Reference numeral 27' indicates a joint at the protruding end of the output shaft, and the protruding upper part of the central shaft 22 of the pinion 21 mentioned above is engaged with this joint 27'.

Further, in the case of this example, the DC motor 25 is fixed to a U-shaped holding frame 28 such as a band material, and both legs 28 of this holding frame are
' are attached to the left and right side surfaces of the device case consisting of the upper and lower halves 2 and 3 (it is preferable to make them removable).

That is, if the configuration as shown is adopted, the torque scale of the internal meter unit can be sufficiently visually observed from the upper surface of the transparent upper half 2 when measuring torque.

In the case of torque measurement, the status motor 25 switches its polarity as desired, and the rotation speed of the output shaft 27 is decelerated to such an extent that the outer ring of the meter unit rotates once every 3 to 4 seconds. 20 (FIG. 2) can be clearly read.

From the above, the effects of the present invention are already clear. When measuring rewind or fast-forward torque, dynamic torque measurement is possible by rotating the outer ring of each meter unit at a low speed in the direction of rotation of its inner ring. This improvement should be highly praised, and its practical effects are significant.

Note that the present invention can be applied to various cassette tape recorders other than compact cassette tape recorders.

[Brief explanation of drawings]

Fig. 1 is a plan view for explaining a conventional rewind/fast forwarding torque measuring device, Fig. 2 is a plan view showing an embodiment of the torque measuring device of the present invention, and Fig. 3 is an example of driving means for a driving pinion. FIG. 2 is a perspective view of the entire device. In the figure, 2 and 3 are the upper half and lower half, 16A and 16
B is a meter unit, 17a and 17b are inner rings, 18a
18b is a gear outer ring, 19 is an index, 20 is a torque scale, 21 is a driving pinion, 22 is its shaft, 25 is a DC motor, 27 is a drive shaft, and 27' is a joint.

Claims (1)

[Scope of utility model registration request] A meter unit with a spring balance structure is provided on the feeding side and the winding side of the cassette, and includes an inner ring that engages with each reel shaft of the tape recorder, and outer rings arranged around the inner rings on both sides. In a device configured to specify the relative rotational displacement amount between the inner ring and the outer ring of the feeding meter unit or the winding side meter unit as a torque scale in the rewinding or fast forwarding mode, Each outer ring is a gear, and a driving pinion that meshes with the outer rings of both gears is provided so that when measuring rewind or fast forward torque, the outer ring of the gear on the measurement side rotates at a low speed following the rotational direction of the inner ring. A torque measuring device for a cassette cheap recorder.