JPH1123437A - Method and equipment for measuring flexural rigidity of rod-like material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an equipment for measuring the flexural rigidity of a rod-like material accurately in which the flexural rigidity of a rubber hose can be measured quantitatively at a low temperature and at the application of pressure. SOLUTION: The flexural rigidity measuring equipment 10 comprises a semicircular, planar bending mender 12 having a radius of curvature R secured vertically and removably onto a supporting table 11 by means of screws 13. The planar bending mandrel 12 is fixed, on the side face thereof, with the supporting arm 15 of a pressing means provided with a detector turning, at a constant speed, along the side face of the planar bending mandrel 12. The supporting arm 15 has a base end part 15a fixed to a turning shaft 16 located in the center O of the bonding mandrel 12 and a forward end 15b fixed, through a bracket 17, with rotatable guide rollers 18a, 18b provided with a guide groove 30 covering the substantially semicircular part of a rod-like measured material W, and flexure detectors 19a, 19b, e.g. load cells, for measuring the flexural rigidity (normal force).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring the bending stiffness of a rod-shaped material such as a rubber hose, a wire, a metal rod, a resin rod and the like. The present invention relates to a method and an apparatus for measuring a bending rigidity of a material.

[0002]

2. Description of the Related Art Conventionally, a method of measuring the bending stiffness (bending force) of a rod-shaped material such as a rubber hose is shown in FIG. 7 by clamping the base end of a rubber hose W to a fixing jig 1 such as a vise. Then, a spring scale 3 (not shown) is attached to the other end of the predetermined length L and pulled, and bent in a semicircular shape as shown by a two-dot chain line. The template 2 having the radius R drawn thereon was applied thereto, and the curvature radius R at that time and the spring balance were read and measured. Therefore, at least two workers were required for the measurement work.

[0003]

However, the method in which at least two workers measure the bending stiffness using the spring scale as described above has the following various problems. . Since the speed at which the rubber hose W is bent is not constant, there is great variation among the measurers, and high-precision measurement cannot be performed. . Since the direction of the bending force is not determined, the measurement point on the template 2 on which the bending radius R is drawn cannot be accurately read. . When the bending force is maximum (when the bending radius is too small), the fixed end of the rubber hose W is displaced and accurate measurement cannot be performed. . In the case of a rubber hose, the bending force at a low temperature does not become a semicircular shape and is broken in the middle, so that the bending force cannot be measured. . Bending force of rubber hose when pressurized cannot be measured.

[0004] It is an object of the present invention to accurately measure the bending stiffness of a rod-shaped material.
It is an object of the present invention to provide a method and an apparatus for measuring the bending stiffness of a rod-shaped material, which can quantitatively measure the bending stiffness at the time of low temperature and pressure.

[0005]

In order to achieve the above object, a method for measuring the bending stiffness of a bar-shaped material according to the present invention is characterized in that a bending mandrel having an arc-shaped guide surface on the outer periphery is fixed to a support table, Pressing means with a detector movable along an arc-shaped guide surface is provided, and a bar-shaped material to be measured, one end of which is fixed to the support, is bent by the pressing means with the detector, and the detection is performed at an arbitrary position. The gist of the present invention is to measure the bending stiffness of the bar to be measured using a measuring instrument.

Further, according to the apparatus for measuring the bending stiffness of a rod-shaped material of the present invention, a semicircular bending mandrel having a guide surface of a bar-shaped material to be measured and having a predetermined radius of curvature is installed on a support table. At one end of the bending mandrel, a fixing means for supporting one end of the bar-like material to be measured is provided, and a detector capable of turning the bar-like material to be measured along the guide surface on the outer periphery of the bending mandrel. The gist of the present invention is to provide a pressing means.

[0007] The bending mandrel having the arcuate guide surface is fixed to the support table, and a pressing means with a detector movable along the arcuate guide surface is provided.
Since the bar to be measured having one end fixed to the support table is bent by the pressing unit with the detector, the bending rigidity of the bar to be measured is measured by the detector at an arbitrary position thereof. The accurate bending rigidity can be measured by automatic measurement, and in the case of a rubber hose, the bending rigidity at a low temperature or under pressure can be quantitatively measured.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a front view of a bending stiffness measuring device for carrying out the method for measuring the bending stiffness of a rod-shaped material according to the present invention, FIG. 2 is a side view thereof, and FIG. FIG.

In the bending rigidity measuring device 10, a semicircular plate-shaped bending mandrel 12 having a radius of curvature R is vertically fixed on a supporting base 11 via a screw 13 so as to be detachable. On the guide surface on the outer periphery of the bending mandrel 12,
A guide groove 14 having a concave cross section is formed to cover a substantially semicircular portion of a rod-shaped material W to be measured, which is formed of a rod-shaped material such as a hollow, solid or plate-shaped rubber hose, resin hose, wire, metal rod, resin rod, or the like. .

On one side of the support base 11, a fixing means 11a comprising a fixing plate and a bolt for detachably clamping one end of the bar W to be measured is provided. On the side surface of the plate-shaped bending mandrel 12, a support arm 15 of a pressing unit with a detector that pivots and moves at a constant speed along the side surface of the bending mandrel 12 is provided. A guide groove is attached to a pivot shaft 16 provided at the center O of the bending mandrel 12, and is provided at a tip 15 b of the support arm 15 through a bracket 17 so as to cover a substantially semicircular portion of the bar W to be measured. And rotatable guide rollers 18a and 18b provided with a bending detector 30 and bending detectors 19a and 19 such as load cells for measuring bending rigidity (normal force).
b is attached.

The bracket 17 is supported by a support arm 15 via a position adjusting mechanism 22 such as a spring 20 and a screw shaft 21.
Of the bending mandrel 12 and the bending radius of the bar W to be measured. The above guide rollers 18a, 18b
As an embodiment of the present invention, as shown in FIG.
Rotatable guide roller 18 provided on the same axis as -P
a and a position slightly shifted from the rotation center line PP, that is,
Guide roller 1 arranged in the circumferential direction of an arc-shaped guide surface
8b and a two-roll system.
The interval between 8a and 18b is attached to the bracket 17 so as to be movable and adjustable, corresponds to the flexibility and the nominal diameter (D) of the hose, and can be adjusted in the range of 1 to 3D.

The pressing means is not limited to the guide rollers 18a and 18b as described above. As shown in FIG. 3B, the guide roller 18a and the width H of the bending mandrel 12 are used.
Is made wider with respect to the diameter Da of the bar W to be measured, and has a circular arc larger than the radius of the bar W to be measured.
4, the rod-shaped material W to be measured and the guide rollers 18a, 18
By reducing the contact portion with b, that is, by making it a point contact state, it is also possible to provide a structure that does not excessively deform the bar W to be measured.

The pressing means may be formed as guide members 23a and 23b having a concave cross section as shown in FIG. 4A, or the guide groove 14 of the bending mandrel 12 may be formed with a concave cross section. . Further, as shown in FIG. 4 (b), both end flange portions 2 of the guide members 23a, 23b having a concave cross section are provided.
3x and both end flange portions 12x of the bending mandrel 12 are formed shorter than those in FIG. 4A, and the bar member W to be measured and both end flange portions 23x of the guide members 23a and 23b and both end flanges of the bending mandrel 12 are formed. Reduce the contact part with the part 12x,
It is also possible to adopt a structure that does not excessively deform the bar-like material W to be measured.

A turning shaft 16 to which the base end 15a of the support arm 15 is connected is rotatably supported via a bearing 24. The turning shaft 16 is connected to the support base 1 via a coupling 25.
1 is connected to a drive motor 26 installed on the drive motor 1. A chain 27, a sprocket 28
The rotation angle detector 29 for detecting the turning angle of the pressing unit 15 with the detector is connected via the control unit.

Next, a method for measuring the bending stiffness of the bar W to be measured will be described. First, the bending mandrel 12 corresponding to the bending radius of the bar-like material W to be measured for measuring the bending stiffness is selected and fixed on the support base 11, and the turning mandrel 12 turns along the outer peripheral surface of the bending mandrel 12. The proximal end 15a of the support arm 15 of the pressing means with a container is connected to the distal end 15 of a pivot shaft 16 provided at the center O of the bending mandrel 12.
The positions of the guide members 18a and 18b attached to the position b are adjusted via the position adjusting mechanism 22.

In this state, the fixing means 1 is provided in which one end of the bar W to be measured is provided on one side of the support base 11.
1a, and a guide groove 14 having a concave cross section of a guide surface formed by forming the bar W to be measured into a semicircular shape of a bending mandrel 12 and an outer peripheral surface side of the bar W to be measured are fixed by a fixing means 1.
The guide members 18a and 18b moved to the side 1a are held so as to be sandwiched between the guide grooves 30 of the guide members 18a and 18b.

In this state, the support arm 15 is driven by the drive motor 26 to rotate the guide members 18a, 18b at a constant speed along the outer circumferential guide surface of the bending mandrel 12, and the rotation angle at that time is changed to the rotation angle. Detector 2
While detecting in step 9, the bending stiffness force with respect to the bending radius of the bar W to be measured is continuously and automatically measured by the bending detectors 19a and 19b.

As described above, one end of the bar W to be measured is fixed to the fixing means 11a provided on one side of the support base 11, and
The bending stiffness force with respect to the bending radius of the bar W to be measured can be continuously or automatically measured to an arbitrary position (arbitrary angle) without manual operation while rotating the support arm 15 at a constant speed. In the above-described embodiment, an example in which the measured bar-shaped material W is bent upright in the vertical direction has been described. However, the measured bar-shaped material W is installed in the horizontal direction, and is bent in the horizontal direction along the mandrel. It is also possible to configure so as to eliminate the influence of the weight of the rod-shaped material W to be measured.

After measuring the bending rigidity of one of the rods, by inverting the fixed end of the bar W to be measured, the bending rigidity of the other can be easily measured. Since the bending mandrel 12 is detachably mounted on the support base 11, the bending mandrel 12 can cope with any bending radius with a space-saving and one-touch mounting. Furthermore, it is possible to bend in a smooth semicircular shape even during low-temperature bending using a thermostat or the like, and it is also possible to measure the bending rigidity.

Further, when the rod-shaped material W to be measured is a hose, the measurement can be performed in a state where an internal pressure is applied to the hose. Also, by making a program, a graph (chart) of the automatic measurement result can be made at the same time.

[0021]

The present invention is constructed as described above, and has the following excellent effects. . Since the rod to be measured is continuously and automatically measured, the measurement accuracy is improved as compared with the conventional manual measurement, and the reliability of the bending rigidity can be increased. . This makes it possible to quantitatively measure the bending stiffness at the time of low temperature and pressure, which was conventionally considered difficult to measure. . It becomes possible to measure the bending stiffness force in various mounting shapes, and this is an effective means for stress analysis of the metal fitting end. . Since the continuous measurement and the bending speed of the bar to be measured are variable, the relationship between the bending speed and the bending force can be easily grasped. . The bending force in any direction can be measured irrespective of the bending habit of the bar material to be measured. Therefore, the detection of a bending defect is also useful. . The work of measuring the bending stiffness at the time of low temperature and pressurization can be made lighter and safer, and labor can be saved. . Not only the measurement of the bending stiffness of the rubber hose, but also the measurement of the bending stiffness of a rod-shaped body such as a wire, a metal rod, and a resin rod can be easily performed.

[Brief description of the drawings]

FIG. 1 is a front view of a bending stiffness measuring apparatus for carrying out a method for measuring a bending stiffness of a bar according to the present invention.

FIG. 2 is a side view of FIG.

FIG. 3A is an enlarged cross-sectional view taken along the line AA of FIG. 2;
(B) is a sectional view showing another embodiment of the pressing means.

FIG. 4A is a cross-sectional view showing an embodiment of the shape of a guide groove of a bending mandrel for holding a bar-shaped material to be measured and the shape of a guide groove of a guide member. FIG. It is sectional drawing which shows other embodiment of the shape of the guide groove of this, and the shape of the guide groove of a guide member.

FIG. 5 is an enlarged front view of a guide roller.

FIG. 6 is an enlarged front view of a bending mandrel.

FIG. 7 is an explanatory view showing a conventional method for measuring the bending stiffness of a rubber hose.

FIG. 8 is an explanatory diagram of a template used for a conventional bending rigidity measuring method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Flexural rigidity measuring device 11 Support stand 11a Fixing means 12 Bending mandrel 13 Screw 14 Guide groove 15 Pressing means with detector 15a Base end 15b Tip 16 Rotating shaft 17 Bracket 18a, 18b Guide roller 19a, 19b Bending detector 20 Spring 21 Screw shaft 22 Position adjustment mechanism 23a, 23b Guide member 24 Bearing 25 Coupling 26 Drive motor 27 Chain 28 Sprocket 29 Rotation angle detector 30 Guide groove W Rod material to be measured

Claims (3)

[Claims] 1. A bending mandrel having an arcuate guide surface on its outer periphery is fixed to a support table, and a pressing means with a detector movable along the arcuate guide surface is provided. A method for measuring the bending rigidity of a rod-shaped material, comprising: bending a rod-shaped material to be measured to which is fixed by the pressing means with a detector, and measuring the bending rigidity of the rod-shaped material to be measured by the detector at an arbitrary position. 2. A semicircular bending mandrel having a predetermined radius of curvature provided with a guide surface of a bar material to be measured is set on a support table, and one end of the bending mandrel is provided with a bar shape to be measured. The bending stiffness of the rod-shaped material is provided by providing fixing means for supporting one end of the material, and providing pressing means with a detector on the outer peripheral portion of the bending mandrel so that the rod-shaped material to be measured can be turned along the guide surface. Force measuring device. 3. The pressure means comprises: a pair of guide rollers arranged in front and rear in the circumferential direction of the arcuate guide surface; and a support arm having a center of curvature radius of the arcuate guide surface as a rotation fulcrum. The apparatus for measuring the bending stiffness of a rod-shaped member according to claim 2.