JPS5920661Y2 - Load measuring device for nail pulling test machine - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of a testing machine for measuring the pull-out load of nails driven into wood, asbestos-cement boards, and other articles.

In the conventional testing machine of this kind, as shown in FIG. 5, a dial gauge B2 is fixed to one side of an elastically deformable annular outer frame B1, and the gauge mounting outer frame moves in the tensile direction. Some devices read a negative value due to the movement of the measuring stylus B3 toward the other end of the outer frame.

However, in this device, the pointer of the dial gauge returns to zero at the moment the nail A comes out due to the elastic recovery of the tension side of the annular outer frame.

Commercially available dial gauges cannot be set to negative values, so it is not only difficult to check the maximum value, but also the dial gauges are frequently damaged due to shock when the outer frame is elastically restored.

There is also a so-called compression gauge type device in which the compression on the gauge head is changed to the rotation of the pointer, but in order to maintain a stationary state on the compression side of the annular outer frame when the nail comes out, a worm is used. , it is necessary to use a worm car, and the provision of these gear boxes makes the device itself large (approximately 30 kg), which limits the range and location of use, and makes it difficult to easily carry and move it, making it difficult to put into practical use. It wasn't something I did.

The present invention eliminates the above-mentioned drawbacks, makes it possible to suppress the shock to the measuring head of a dial gauge by automatically restoring the elastic annular outer frame, and provides a measuring device that can be miniaturized to the extent that it can be carried by hand and has high accuracy. The purpose is to

In order to achieve the above object, the structure of the present invention is as follows.

A dial gauge is mounted via a gauge mounting arm fixed to either the upper or lower thick wall portion of an annular outer frame that can be elastically deformed in the vertical direction, with its gauge pointing toward the thick wall portion on the fixed side of the mounting arm. .

Inside the outer frame, an annular inner frame is inwardly fixed to the other thick part of the annular outer frame so as to surround the dial gauge, and the measuring tip end of the dial gauge is brought into contact with the inner surface of the inner frame.

A chuck that can be opened downward is provided on the thick walled portion of the lower portion of the outer frame via a chuck lifting rod, and the thick walled portion of the upper portion of the outer frame is provided with a needle tensioning member.

Then, the end of the measuring tip is compressed in response to deformation of the outer frame due to stress when the nail is pulled out while being held by the chuck.

The effect of this configuration is as follows.

Due to the stress when the nail is pulled out, the annular outer frame deforms to become longer in the vertical direction and moves the dial gauge.At the same time, the inner frame moves in the opposite direction and compresses the dial gauge contact point, causing the dial gauge to move. Indicates a positive value.

Therefore, even if the outer frame suddenly recovers its elasticity during nail extraction, the inner frame moves away from the end of the measuring tip, so no harmful shock is applied to the measuring tip.

Also, since the pointer rotates in the forward direction during measurement, it is possible to place the pointer in the same direction.

An embodiment of the present invention will be described below based on the drawings.

In Fig. 1, the load detector has a through hole 11 in the vertical direction.
The stand 1 is formed by having an upper frame 11 which is rectangular in plan view and is made of a block body 11a having a block body 11b, and a lower frame 12 having a vertical through hole 12a in the center, supported by pillars 13 at the four corners.

A chuck 2 capable of holding a test nail is provided at the bottom of the stand 1 so as to be openable downward.

The chuck 2 is suspended by a chuck lifting rod 3 inserted into the through hole 12a so as to be vertically movable.

A large diameter adjustment ring 3a is fixed to the chuck lifting rod 3.

A nut member 4b is rotatably fitted into the through hole 11b of the upper frame 11, and a bundle 4a is fixed to the upper end of the nut member 4b.

A nail tension threaded rod 4 is screwed into the nut member 4b and passes through the bundle 4a.

Between the tension screw rod 4 and the chuck lifting rod 3, there is an elastically deformable outer frame 5 which has a horizontally long elliptical ring shape.
The elliptical ring portion is interposed so that it lies within the vertical plane.

The elastic outer frame 5 is formed of left and right semicircular elastic parts 51, a lower thick part 52, and an upper thick part 53.

The chuck lifting rod 3 is screwed and fixed to the lower part of the lower thick part 52.

The tension threaded rod 4 is fixed to the upper part of the upper thick part 53.

An elliptical annular inner frame 6 inscribed in the lower thick wall portion 52 of the outer frame 5 and elongated in the vertical direction is fixed with screws so that its elliptical surface is within the vertical plane and forms the same vertical plane as the outer frame 5. Ru.

As shown in FIGS. 1, 2, and 4, the inner frame 6 is provided with outward reinforcing ribs 6a on the side portions, and reinforced with upward curved edges 61, 62 on the upper and lower portions. be done.

A horizontal piece 71 of a gauge mounting arm 7, which is a plate-shaped body having a dotted line in the upper and lower directions, is fixed to the lower surface of the upper thick part 53 of the outer frame 5 with screws.

A bifurcated holding piece 73 is protruded from the lower end of the vertical piece 72, and is fixed with a thumb screw 9 while holding the rear mounting portion 8a of the dial gauge 8.

(See the third diagram). The dial gauge 8 is connected to the indicator 8 as described above.
1 with the reading surface facing away from the vertical piece 72, and the probe 82 is attached upward.

Then, when the pointer of the indicator 81 points to zero in a state where no external force is applied, the tip of the probe 82 is attached so as to come into contact with the upper part of the annular inner surface of the inner frame.

Note that the outer frame 5, inner frame 6, arm 7, and gauge 8 may all be mounted in an upside-down position.

Next, the usage status will be explained.

The chuck lifting rod 3 is positioned directly above the nail A, which is the object to be tested, and the detector is installed, and the chuck 2 grips the nail A. At this time, the adjustment ring 3a is turned to move the chuck lifting rod 3 to the lower part. By changing the insertion length into the thick part 52, it is moved up and down and adjusted so that the gripping part of the chuck 2 is positioned approximately below the neck of the nail A.

Next, the bundle 4a is turned to gradually lift the threaded rod 4.

As a result, the outer frame 5 is elastically deformed upward while the nail A is resting on the wood or other article, and the dial gauge 8 is also lifted upward accordingly, so that the end of the measuring tip 82 is inside. Pressed by the upper inner surface of the frame 6, the pointer of the dial gauge 8 is turned in the positive direction.

The moment the nail A comes out, the elastic deformation of the outer frame 5 is restored and the pointer returns to zero, but in this case, the setting needle 10 is possible and the maximum value indicated by the pointer is stored.

In this way, the maximum nail pullout load can be measured.

Furthermore, even if the outer frame 5 suddenly recovers its elasticity due to a nail coming out, the gauge probe 82 moves away from the contact surface with the inner frame 6, so no harmful shock is applied to the probe.

As described above, in the present invention, a dial gauge is attached to an annular outer frame that is elastically deformable in the vertical direction via a gauge attachment arm, and the dial gauge is mounted on the inner surface of an inner frame that is inscribed and fixed inside the outer frame. Since the lower end can be brought into contact with the gauge needle, the gauge needle can be rotated in the positive direction when a load is applied to set the gauge needle, and even if the needle falls out, no shock will be applied to the gauge head.

Moreover, the outer frame is elastically deformed simply by rotating the tension rod, and the gauge head is pressed, so there is no need for a large gear box, and the device itself is small and inexpensive to manufacture, making it convenient to move. Not only that, but also the measured values can be read accurately.

[Brief explanation of drawings]

Fig. 1 is a front view of the nail pull-out test machine according to the present invention, Fig. 2 is a side view of the main part, Fig. 3 is a plan view of the main part, and Fig. 4 is an enlarged cross-sectional view of Fig. 1. , FIG. 5 is a front view of a main part of a conventional load measuring device. 1...Stand, 2...Chuck, 3
...Chuck pulling rod, 4...Tension rod, 5...Outer frame, 51...Elastic part,
52... Lower thick wall part, 53... Second thick wall part, 6... Inner frame, 7... Gauge mounting arm, 8... ...Dial gauge, 10...
...Standing needle.

Claims (1)

[Scope of utility model registration request] A dial gauge is mounted via a gauge mounting arm fixed to either the upper or lower thick wall portion of an annular outer frame that is elastically deformable in the vertical direction, with its gauge pointing toward the thick wall portion on the fixed side of the mounting arm. , inside the outer frame, an annular inner frame is fixed inwardly to the other thick part of the annular outer frame so as to surround the dial gauge, and the measuring tip end of the dial gauge is brought into contact with the inner surface of the inner frame. , a chuck that can be opened downward via a chuck lifting rod is provided on the thick walled portion of the lower portion of the outer frame, and a needle tensioning member is provided on the thick walled portion of the upper portion of the outer frame, and the nail is held by the chuck. A load detection device for an oblique pull-out tester, wherein the end of the probe is compressed in response to deformation of the outer frame due to stress during pull-out.