JPS5819218B2 - Hardness meter load axis positioning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for positioning the load shaft of a hardness tester, and more particularly to a device for positioning the load shaft by manual operation.

Generally, in a hardness tester, when applying a test load to a sample, the load axis of the hardness tester is determined in advance at a predetermined position in order to apply the test load in an optimal state.

Conventionally, the load axis positioning means for this type of hardness tester is as follows:
Manually raise the screw shaft attached to the upper end of the sample stage, thereby raising the load shaft that comes into contact with the sample on the sample stage, read the upward displacement of the load axis accompanying this upward movement with an indicator, and measure this upward displacement ( An operation was performed so that the indicated value of the indicator) fell within a predetermined range.

However, with such conventional hardness tester load axis positioning means, the load axis is raised while always observing the indicated value of the indicator, and when the indicated value falls within a predetermined range, the load axis is moved upward. Since the lifting operation must be stopped, there is a problem in that this lifting operation of the load axis requires considerable attention and skill.

The present invention aims to solve such problems, and when the load axis of the hardness tester rises and reaches a predetermined position, the lifting operation of the load axis is stopped by electromagnetic means. It is an object of the present invention to provide a load shaft positioning device for a hardness tester, which notifies the user of the load shaft and automatically prevents the continuation of the raising operation so that the load shaft is set at a predetermined position.

For this reason, the hardness tester load axis positioning device of the present invention includes a load lever whose base end is pivotally connected to the hardness tester body and can swing.
a load shaft extending vertically to engage the load lever;
A sample supporting screw shaft is provided on the main body so as to be movable up and down in order to push up the load shaft through the sample, and an operating nut is screwed onto the same screw shaft to move the screw shaft up and down, In order to push the load shaft up to a predetermined position prior to the lowering engagement of the load lever, a load shaft position detector is provided that can detect when the load shaft has reached the predetermined position, and the operation nut is fixed by the operation of the detector. Equipped with an electromagnetic brake that can
This electromagnetic brake attracts a movable magnetic member supported via a suspension mechanism below the nut or a rotating member linked thereto, and receives an excitation current when the detector is activated. and a fixed electromagnet provided on the main body to fix the movable magnetic member, and the suspension mechanism allows the movable magnetic member to descend when the movable magnetic member is attracted by the fixed electromagnet. The device is characterized in that it is configured as an elastic suspension mechanism including an elastic member that restrains rotation relative to the nut.

Hereinafter, a load axis positioning device for a hardness tester as an embodiment of the present invention will be explained with reference to the drawings. Fig. 1 is a front view partially showing the main part in longitudinal section, and Fig. 2 is an enlarged view of the main part. The vertical cross-sectional view and FIG. 3 are plan views of the elastic member in the movable magnetic member suspension mechanism, and as shown in FIG. It is pivoted.

The load shaft 3 extends vertically to engage with the load lever 1 via an intermediate shaft 3', and the intermediate shaft 3' is connected to a knife 4 formed on the lower side near the base end 1a of the load lever 10. It has an abutting upper end 3'a, is inserted into a spring receiver 2a screwed into the main body 2, and is supported so as to be slidable up and down via a support spring 2b.

Furthermore, a sample stand 6 is provided at the upper end of the sample support screw shaft 5 whose outer periphery is threaded, and the screw shaft 5 is connected to the sample I on the sample stand 6 and an indenter attached to the lower end of the load shaft 3. It is vertically movably fitted into a guide tube 9 provided in the main body 2 so that the load shaft 3 can be pushed up via the guide tube 8 .

The guide tube 9 is fixed to the main body 2, and the screw shaft 5 is fitted into the guide tube 9 so as to be disposed concentrically with the load shaft 3. A rotation stopper key and a key seam (not shown) are provided and engage with each other.

Further, a manual operation nut 11 having a handle 11a on the outside is screwed into a lever for raising and lowering the screw shaft 5.

In order to push the upper end of the load shaft 3 up to a predetermined position prior to the lowering engagement of the load lever 1, a switch 12 is used as a load shaft position detector capable of detecting the arrival at the predetermined position.
is provided.

This switch 12 has a first section 12a and a second section 12b.
The first section 12a is attached to the base end of an enlarged lever 140 that magnifies and transmits the vertical displacement of the load shaft 3 via the contact piece 13 attached to the load shaft 3, and the second section 12a
2b is attached to the main body 2.

Note that the switch 12 as a load shaft position detector is composed of the first section 12a and the second section 12b described above, as well as the switch 12 that is composed of the relay, the load shaft 3, or the support shaft 1 of the expansion lever 14.
It may be a microswitch that operates by rotational displacement about 4a, or an electronic circuit switch that converts the displacement electrically and operates based on the electrical output.

The upper part 3a of the load shaft 3 has a convex longitudinal section,
This upper part 3a has a spring catcher 2 having a conical or spherical surface.
2 is engaged with the hole, and a coil-shaped reference load spring 23 is loaded between the spring receiver 22 and the spring receiver 2a.

In addition, a leaf spring 2 is placed on the top of the load shaft 3 to support it.
4 is attached to one end, and the other end is attached to the main body 2.

In addition, a test load weight 2 is attached to the free end 1b of the load lever 1.
5 is hanging.

In order to control the test load by this weight 25,
A control shaft 26 is provided to abut on the lower side of the load lever 1 near the free end 1b, and a control shaft 26 is provided to move the control shaft 26 up and down along guide holes 27 and 28 formed in the main body 2. A cam 29 is mounted so as to come into contact with a roller 26a at the lower end of the control shaft 26.

Note that an electromagnetic means may be used instead of the weight 25, and the test load may be applied by electromagnetic force.

Further, a spindle 30 of a displacement meter 31 attached to the main body 2 is arranged so as to be in contact with the free end 14b of the enlarging lever 14.

Note that the reference numeral 32 in the figure indicates a stopper/load shaft support portion formed on the main body 2 so as to be able to support the lower part of the load shaft 3.

Further, the electromagnetic brake 35 locks the operating nut 11 so that the operating nut 11 can be fixed by actuation of the switch 12.
and the guide tube 9.

As shown in FIG. 2, this electromagnetic brake 35 includes a movable magnetic member 36 that can rotate integrally with the lower side of the nut 11, and a movable magnetic member 36 that is excited when the switch 12 is closed.
A fixed electromagnet 37s is attached to the main body 2 via a guide tube 9 in order to attract and fix it.

The movable magnetic member 36 is formed in a donut shape and is suspended below the nut 11 via an elastic suspension mechanism 38 including a leaf spring 38a as an elastic member, as shown in FIG. The leaf spring 38a is also formed in a donut shape,
The six bolt insertion holes 39a and 40a listed above
As shown in FIG. 2, bolts 39 that connect the leaf spring 38& to the lower side of the nut 11 and bolts 40 that connect the leaf spring 38a to the movable magnetic member 36 are inserted alternately.

Therefore, due to the deformation of the leaf spring 38a, the movable magnetic member 3
While the movable magnetic member 36 and the nut 11 are allowed to move up and down, the movable magnetic member 36 and the nut 11 can rotate together.

Note that the elastic members included in the elastic suspension mechanism 38 include:
It is not limited to the leaf spring 38a, but may be a telescopic cylinder with a built-in coil spring.In short, when the movable magnetic member 36 is attracted downward, it is allowed to descend, but its relative rotation with respect to the nut 11 is allowed. It suffices if it is something that restricts.

The electromagnet 378 includes an annular cylindrical fixed magnetic member 37 disposed concentrically with the lower cylindrical projection 11b of the nut 11;
A coil 37b is assembled in an annular groove 37a on the upper surface of the fixed magnetic member 37, and the magnetic member 37 is fixed to the upper surface of the guide tube 9.

Further, as shown in FIG. 1, the coil 37b is connected to a control device 41 including a power source, and when the switch 12 is closed, the coil 37b is excited via the control device 41.

Since the load shaft positioning device of the hardness tester of the present invention is configured as described above, the upper end 3a of the load shaft 3 is pushed up to a predetermined position prior to the lowering engagement of the load lever 1. To detect the arrival of the screw shaft 5, first manually operate the handle 11a of the operating nut 11.
When the screw shaft 5 is raised, the sample stage 6 is raised.
The upper sample 7 also rises.

When the handle 11a is further operated to raise the screw shaft 5, the sample 7 and the indenter 8 come into contact with each other, and then as the screw shaft 5 rises, the load shaft 3 also rises against the reference load spring 23.

At this time, the enlarging lever 14 rotates about the support shaft 14a at the base end via the contact piece 13, and the first piece 12a of the switch 12 rotates in conjunction with this rotation.

Furthermore, when the load shaft 3 is raised by operating the handle 11a of the operating nut 11 and the screw shaft 5 is raised, and the load shaft 3 is pushed up to a predetermined position, the first section 12a of the switch 12 is 2 contacts the section 12b.

In this way, the first section 12a and the second section 1 of the switch 12
When the control device 41 is activated by contacting and closing the electromagnetic brake 2b, a current flows through the coil 37b of the electromagnetic brake 35, so that the fixed magnetic member 37 is magnetized and comes to work as an electromagnet 378, and the fixed magnetic member 37 attracts and engages the movable magnetic member 36, and in this way the electromagnetic brake 35
fixes the operating nut 11.

Then, until the switch 12 is closed, the movable magnetic member 3
6 and the fixed magnetic member 37, the rotation of the nut 110 by the handle 11a is performed extremely smoothly, and the above-mentioned method that does not cause wear to each magnetic member 36, 37 is achieved. When a current flows through the coil 37b and the movable magnetic member 36 and the fixed magnetic member 37 are engaged by attraction,
The movable magnetic member 36 is connected to the operating nut 1 via the leaf spring 38a.
1 and that the fixed magnetic member 37 is fixed to the main body 2 via the guide tube 9, it becomes impossible to continue operating the handle 11a, and as a result, the load axis 3 will stop at a predetermined position.

At this time, a required clearance is maintained between the load shaft 3 and the intermediate shaft 3', and the reference load state by the spring 23 is maintained.

In this way, when the load shaft 3 reaches a predetermined position, the switch 12 is actuated and the electromagnetic brake 35 is applied to the operating nut 1.
1 is fixed and the operation of the handle 11a, that is, the continuation of the lifting operation of the load shaft 3 is automatically prevented, so that the lifting operation of the load shaft 30 to a predetermined position, that is, setting it to the reference load state is extremely simple and easy. It will definitely be done.

In addition, in this device, an elastic suspension mechanism 38 is provided below the nut 11.
The movable magnetic member 36, which is suspended and supported via the fixed electromagnet 37s, is opposed to the fixed electromagnet 37s with a slight gap, and is attracted downward in a cushioning manner by the deflection of the leaf spring 38a as an elastic member. There is no risk of shock when the movable magnetic member 36 is attracted and fixed by the fixed electromagnet 378.

Furthermore, in this device, the movable magnetic member 36 can be placed extremely close to the fixed electromagnet 37s when not in operation, so that the product of the number of turns of the coil 37b of the fixed electromagnet 37s and the current, that is, the ampere-turn, can be reduced. 3
Another advantage is that the 7s can be made smaller.

In this way, after the screw shaft 5 stops rising, the cam 29 is driven to lower the control shaft 26, and the weight 2
6 is transmitted to the sample 7 via the load lever 1, the knife 4, the intermediate shaft 3/, the load shaft 3, and the indenter 8, thereby making it possible to obtain an indentation of the indenter 8 according to the hardness of the sample 7. can.

The hardness of the sample 7 is then measured by measuring this indentation using a displacement meter 31 or a microscope (not shown).

In the above-mentioned embodiment, the electromagnetic brake 35 was provided directly under the operating nut 11, but as shown in FIG. It may also be provided below the rotating member 45 that interlocks via the shaft 44.

In this case as well, the same effects as in the above-mentioned embodiment can be obtained.

As described in detail above, according to the hardness tester load axis positioning device of the present invention, when the load axis is raised and the load axis reaches a predetermined position, the electromagnetic The brake engages with the operating nut, automatically preventing the load shaft from continuing to move upward, and setting the load shaft in place.Moreover, the movable magnetic member of the electromagnetic brake is placed under the operating nut. It is suspended and supported via an elastic suspension mechanism that includes a leaf spring on the side, and this combined with the ability to elastically move relative to the same nut only in the vertical direction greatly simplifies the positioning operation of the load shaft. It has the advantage that it can be carried out very smoothly and accurately.

In addition, in the device of the present invention, the movable magnetic member is suspended and supported by a leaf spring so as not to overload the fixed electromagnet at all times, so when the movable magnetic member rotates together with the operating nut, the movable magnetic member Another advantage is that there is no wear between the two.

Brief description of the drawings: Figure 1 is a front view partially showing a main part of a load axis positioning device for a hardness tester as an embodiment of the present invention in longitudinal section;
3 is a plan view of an elastic member in the movable magnetic member suspension mechanism, and FIG. 4 is a partial longitudinal sectional view showing a modification of the essential portion.

1...-load lever, 1a...base end of the load lever, 1b...free end of the load lever, 2...
...Hardness tester body, 2a... Spring holder, 2b
......Support spring, 3...Load shaft, 3a.
・・・・・・Upper part of load shaft, 31・・・・・・Intermediate shaft, 3
'a...Top end of intermediate shaft, 4...Knife screw, 5...Screw shaft for supporting sample, 6...
- Sample stage, 7... Sample, 8... Indenter, 9... Guide tube, 11... Operating nut, 11a...・Natsuto's handle, 11b...
... Lower cylindrical projection of the nut, 12 ... Switch as a load axis position detector, 12a ...
First section of the switch, 12b... Second section of the switch, 13... Contact piece, 14... Enlargement lever, 14a... Base of the enlargement lever. End support shaft, 14b...Free end of enlargement lever, 22...
...Spring tray, 23...Standard load spring, 2
4... Leaf spring, 25... Weight for test load, 26... Control shaft, 26a... Roller, 27, 28...・Guide hole, 29...
Cam, 30...Spindle, 31...
Displacement meter, 32... Stopper and load shaft support part, 3
5°°°"°° electromagnetic brake, 36...movable magnetic member, 37... fixed magnetic member, 37a...
...Annular groove, 37b...Coil, 37s...
...Fixed electromagnet, 38...Elastic suspension mechanism,
38a...Plate spring as an elastic member, 39.4
0...Bolt, 39a, 40a...
Bolt insertion hole, 41...-control device, 42゜43
... Gear, 44 ... Rotating shaft, 45 ...
...Rotating member.

Claims (1)

[Claims] 1. A load lever whose base end is pivotally connected to the hardness tester main body so as to be able to swing, a load shaft extending vertically to engage with this load lever, and the above-mentioned main body to push the load shaft up through the sample. A screw shaft for supporting a sample is provided to be movable up and down, and an operating nut is screwed onto the screw shaft to raise and lower the screw shaft. The electromagnetic brake is equipped with a load shaft position detector that can detect when the load shaft has reached the predetermined position, and an electromagnetic brake that can fix the operating nut by the operation of the detector. A movable magnetic member is supported via a suspension mechanism on the lower side of a rotating member interlocked with this, and a movable magnetic member is provided on the main body to attract and fix the movable magnetic member by receiving an excitation current when the detector is activated. The suspension mechanism allows the movable magnetic member to descend when the movable magnetic member is attracted by the fixed electromagnet, but restricts the relative rotation of the movable magnetic member with respect to the nut. 1. A load axis positioning device for a hardness tester, characterized in that it is configured as an elastic suspension mechanism including a leaf spring.