JPH0645222Y2 - Material testing machine - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to a material testing machine, and more particularly to a driving device for the power meter.

B. Conventional Technique As a conventional driving device for a force gauge, the one shown in FIG. 5 is known. For example, the balanced beam 71 is tilted according to the pressure of the ram cylinder, and the tilt angle is detected by the differential transformer 72. The detection output is amplified by the servo amplifier 73 to drive the servo motor 74, and the pulley 76 is rotated via the gear train 75. The rotation of the pulley 76 moves the wire 79 spanned between the pulleys 77 and 78, and drives the balance balance unit 80 so that the balance beam 71 becomes horizontal. The rotation of the pulley 76 at this time causes the pointer 81 to rotate.

C. Problems to be Solved by the Invention In this conventional device, the motor 74 and the pulley 76 are connected by the gear train 75, and the mechanism thereof is complicated. Further, the accuracy of the axial distance between the motor and each gear or between the pulley and each gear has been required. Further, noise is generated when the gears are meshed with each other, and vibrations when the motor is rotating are transmitted to the pointer through the gears, which adversely affects the pointing accuracy of the pointer.

An object of the present invention is to provide a material testing machine equipped with a driving device for a power meter that solves such a problem.

D. Means for Solving the Problems The driving device of the force gauge in the material testing machine according to the present invention is
A stepping motor, which is driven to rotate according to the load applied to the test piece, and a belt transmission means for transmitting the output of the stepping motor to the rotating shaft of the pointer, and a pointer of the chassis provided behind the pointer. A bearing part supporting the rotary shaft of the pointer is provided on the side opposite to the side facing the, and the stepping motor is supported by this bearing part, and the output shaft and the rotary shaft of the pointer are connected by belt transmission means. This solves the above-mentioned problems.

E. Action When the motor rotates according to the load applied to the test piece, the pointer rotating shaft rotates via the belt transmission means and the pointer indicates the load. Since it is a belt conduction type, the distance accuracy between the motor and the rotation axis is not required as in the past. Also,
There is no noise such as gear conduction, and the vibration associated with motor rotation is absorbed by the belt transmission means, so the pointer pointing accuracy is improved. Since the bearing portion that supports the rotating shaft of the pointer is projected on the back surface side of the chassis (the side opposite to the side facing the pointer) and the stepping motor is supported by this bearing portion,
All the mechanisms from the stepping motor to the rotating shaft of the pointer are assembled in the same chassis, which improves the assembly and disassembly. The bearing portion is located substantially in the center of the chassis as the center of rotation of the pointer, and the vibration generated between the stepping motor and the rotating shaft of the pointer is concentrated on this bearing portion, so that the vibration of the chassis is suppressed. Since uneven rotation and vibration of the output shaft of the motor are buffered by the belt transmission means, the pointer can be continuously and smoothly driven even if a stepping motor that performs step driving is used.

F. Embodiment FIG. 1 to FIG. 3 show an embodiment of the driving device of the power meter according to the present invention.

1 to 3, the chassis 11 includes a rotation indicator 10
A case 12 for supporting the is screwed vertically with bolts 61, and a glass plate 13 is mounted in front of the chassis 11. A pointer 14 is rotatably supported on the chassis 11, and a scale 62 is printed on the surface of the chassis along a circumference of a predetermined radius centered on the rotation axis X thereof. The scale 62 is, for example, the diameter
It is divided into 1000 equal parts at 450 mm. The pointer 14 is rotated at a 1/5000 pitch, for example, by a drive mechanism attached to the chassis 11.

A bearing holder 21 is screwed to the back surface of the chassis 11 with bolts 22. For this attachment, the bearing holder is fitted in the centering groove 11b on the back side of the through hole 11a formed in the chassis 11.
The centering protrusion 21a of 21 is fitted, and the through hole 11a
The center of the bearing and the bearing holder 21 are centered. A pair of bearings 23 are provided inside the bearing holder 21 to rotatably hold the rotating shaft 24 of the pointer 14. The pointer 14 is clamped and fixed between the head collar portion 24a of the rotary shaft 24 and the nut 25, and is prevented from rotating by the screw 25 by the screw 26. Rotating shaft 24
Protrudes from the bearing holder 21 and there is a large gear (for example, the number of teeth
120) 27 are fixed with bolts 28. On the other hand, a pointer driving stepping motor (for example, one rotation of 1000 pulses) 30 is suspended from the bearing holder 21 via a holder 29, and a small gear (for example, 24 teeth) 31 is fixed to its output shaft 30a. There is. A precision timing belt 32 made of rubber is hung between the small gear 31 and the large gear 27. Here, the small gear 31, the large gear 27, and the timing belt 32 constitute a belt transmission means.

Here, the holder 29 has a through hole 29a and a slot 29b shown in FIG. 3, the bearing holder 21 is fitted in the through hole 29a, and the slot 29b is tightened with bolts and nuts 33A, 33B. Is frictionally clamped to the bearing holder 21. Also, the holder 29
The motor mounting plate 34 is attached to the motor mounting plate 34.
A motor 30 is screwed onto the. The motor mounting plate 34 is moved in the vertical direction in the figure to adjust the distance between the motor output shaft 30a and the pointer axis X, and the tension of the timing belt 32 is adjusted.

According to the load detected by the load detector (not shown), when a drive signal is input to the motor 30, the motor 30 rotates and becomes 1/5 speed via the small gear 31, the timing belt 32, and the large gear 27. It is decelerated to rotate the pointer rotary shaft 24, which
14 rotates to indicate a predetermined scale 62. Now, when one pulse is given to the stepping motor 30, the pointer 14 rotates by (360/5000) degrees. In the above, the case of displaying loads of 10t and 50t series was explained, but in the case of 30t series, if the number of teeth of the small gear is 24, the pointer 14 per pulse (36
0/4800) degree only.

The vibration of the holder 29 accompanying the motor drive is transmitted to the bearing holder 21, but since the bearing holder 21 is installed at the center of the chassis 11, the vibration of the chassis 11 is suppressed. Further, the vibration generated when the power is transmitted from the small gear 31 to the large gear 27 is absorbed by the rubber timing belt 32, and the transmission to the chassis 11 and the pointer 14 is suppressed. Further, since the bearing holder 21 and the pointer driving motor 30 are installed in the same chassis 11, the assembling / disassembling property is good and the mechanism for connecting the two is also simplified.

On the other hand, as described above, when mounting the bearing holder 21,
The bearing holder 21 is installed coaxially with the through hole 11 by fitting the annular centering protrusion 21a into the centering groove 11b of the chassis through hole 11a. Also, set the scale 62 on the chassis 11 to the through hole 11a.
It is provided on the circumference of a predetermined radius centered on the axis X of. Therefore, the center of rotation of the pointer 14 and the center of the scale 62 are both the axis X, and the pointer 14 accurately indicates the predetermined position of the scale 62 at any rotation angle position. Further, since the stepping motor 30 has a high rotation control accuracy and a large static torque, a more accurate pointer drive becomes possible in combination with the above configuration, and a more accurate instruction can be made.

Above, the slot 29 is attached to the holder 29 of the pointer driving motor 30.
After forming b, insert the holder 29 into the bearing holder 21 and
Attach the holder 29 to the bearing holder 21 by bolting 9b.
However, it may be hung by the flange method as shown in FIG. That is, the bearing holder 21 may be provided with the flange 21b, and the holder 29 fitted to the bearing holder 21 may be attached to the flange 21b with the bolt 85. Furthermore, instead of the timing belt system, another belt system such as a V belt may be used.

G. Effect of the Invention According to the present invention, since the pointer driving motor and the pointer rotating shaft are connected by the belt transmission means, the dimensional accuracy between the axes is not required more than before, and the mechanism is simplified. In addition, the assembling and disassembling property is improved. Further, since the belt absorbs the vibration generated when the pointer driving motor is rotated, the pointer can be correctly instructed. Furthermore, the noise caused by the conventional gears is also prevented. All the vibrations generated in the drive system from the stepping motor to the rotating shaft of the pointer are concentrated on the bearings to suppress the vibration of the chassis, and the uneven rotation and vibration of the output shaft of the stepping motor are buffered by the belt transmission means. , It is possible to greatly improve the pointing accuracy by continuously and smoothly driving the pointer while suppressing the vibration of the chassis and the pointer.

[Brief description of drawings]

1 to 3 show a driving device for a force gauge according to the present invention. FIG. 1 is a side sectional view thereof, FIG. 2 is a front view of the force gauge, and FIG. 3 is FIG. FIG. 3 is a view taken along the line III-III of FIG. Fourth
FIG. 5 is a view corresponding to FIG. 1 showing another suspension method, and FIG. 5 is a schematic configuration diagram showing an example of a conventional Leelet type power meter. 10: Power meter, 11: Chassis 11a: Through hole, 11b: Centering groove 12: Case, 14: Pointer 21: Bearing holder, 24: Rotating shaft 27: Large gear, 29: Holder 30: Motor, 31 : Small gear 32: Timing belt

Claims (1)

[Scope of utility model registration request] 1. A stepping motor, which is rotationally driven according to a load applied to a test piece, and a belt transmission means for transmitting the output of the stepping motor to a rotating shaft of a pointer, and behind the pointer. On a side of the chassis provided opposite to the side facing the pointer, a bearing portion for supporting the rotating shaft of the pointer is provided in a protruding manner, and the bearing portion supports the stepping motor to rotate the output shaft and the pointer. A material testing machine, comprising a driving device of a force gauge in which a shaft is connected by the belt transmission means.