JPH07104246B2 - Micro hardness tester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a micro hardness tester for measuring the hardness of a metal material or the like.

[Prior Art] A conventional micro-hardness meter is generally one in which an indenter and an objective lens are attached to a revolver that rotates in a horizontal plane. The load range is 10 to 1000 grf and the load applied to the indenter is The size can be switched in 8 steps. Further, as the load method, a direct load method in which the load of a single weight or a plurality of weights selected from a plurality of weight groups is directly applied on the indenter shaft is adopted.

[Problems to be Solved by the Invention] In the test, the indenter and the objective lens are alternately moved to the test position. However, in the conventional micro hardness tester, when the number of weights increases, the weight is housed in the revolver. It became difficult to rotate and move together with the indenter, and the weight had to be arranged also on the optical axis reaching the objective lens. Therefore, the optical axis must be relayed to bypass the weight, and the structure of the optical system becomes complicated.

[Means for Solving Problems] The present invention adopts the following configuration in order to solve the above problems.

That is, the micro hardness tester according to the present invention includes an indenter pushed into a test piece, a load device for applying a load of a weight to the indenter, and an optical device capable of observing a test point on the surface of the test piece. In the micro hardness tester, a through hole through which the optical axis of the optical device passes is formed in the weight of the load device.

[Function] Since the weight has a through hole through which the optical axis passes, a direct load method is used in which the indenter shaft is directly loaded, and the weight is left on the load shaft when switching from the indenter to the objective lens. Even if it is set, it does not interfere with the optical path. Therefore, the structure of the optical system can be simplified and the number of weights can be increased.

[Examples] Examples described in the drawings will be described below.

The micro hardness tester 1 includes a base 5 provided with an elevating handle 3 for elevating the sample table 2 and a column 7 standing on the base.
It comprises a measuring unit 9 supported by. A stage 10 that moves back and forth and left and right by micrometer heads 8 and 8'is attached to the sample stage 2.
Mounted on 10.

The measuring unit 9 is provided with a load device A and an optical device B.

The load device A has a plurality of weights 15 (15a, 15b, ...) Of large and small sizes. The weight 15 is formed in a cylindrical shape that opens downward,
A through hole 16 is bored in the core portion, and the small weights are sequentially fitted inside the large weight and are superposed on each other.

A hollow shaft 20 is inserted through the through hole 16 in the core portion of the bowl-shaped weights 15, 15, ... Flange-shaped projections 21 and 22 are formed at two upper and lower locations on the outer peripheral portion of the hollow shaft 20, and a telescopic cylinder 23 for adjusting dimensions is screwed to the lower end portion. Hollow shaft
The lower projection 22 of the 20 is engaged with the inner side of the innermost weight 15h.

In the illustrated example, the weight has a cylindrical shape, but it may have a rectangular tube shape. Alternatively, the weight may be a U-shaped meter frame body having a constant width so that they can be overlapped. Also in this case, the through hole 16 can be formed in the central portion.

The lower end of the hollow shaft 20 is the upper flange 25a of the load transmission shaft 25.
It is placed on the load transmission shaft 25 when it is above. The load transmission shaft 25 is slidably fitted in a guide hole 28 provided in the load case 27, and a conical pointed portion 25a is formed at the lower end portion.

An indenter holder 29 holding an indenter 30 is provided below the load transmission shaft 25.
Is provided. The indenter holder 29 is a lever 33 rotatably supported by a fulcrum 32 provided on the load case 27.
One end of the lever 33 is attached, and a pin 34 is laterally projected at the opposite end of the lever 33. The pin 34 has a pivot arm 37 pivotally attached to the load case 27 by a shaft 36.
Are in contact with each other.

The load case 27, which is substantially U-shaped in side view, is rotatably supported within a predetermined angle range in a horizontal plane by a support shaft 43 on the main body case 9a side supported by bearings 41, 41 of a bearing hole 40 provided at the center thereof. ing. On the lower surface side of the load case 27, a measurement objective lens 45 and an observation objective lens 46 are provided concentrically with the indenter holder 29 and at a position sandwiching the indenter holder,
By rotating the load case 27, both lenses 45 and 46 can be positioned at the position of the indenter holder shown in the figure, that is, at the test position immediately below the hollow shaft 20. The load case 27 is provided with a micro switch 35 that detects the position of the load case 27.

The support shaft 43 is formed as a hollow shaft having a through hole in its core, and is attached to the machine frame 50 in the main body case 9a. A transmission shaft 52 of the load adding / removing device C is slidably fitted in a through hole of the support shaft 43, and the transmission shaft 52 is biased upward by a spring 53. A ball is fitted to the lower end of the transmission shaft 52, and the ball comes into contact with the upper surface of the rotating arm 37.

A ball similar to the lower end is also fitted to the upper end of the transmission shaft 52, and the front end of the pivoting body 55 having a hook shape in side view is in contact with the upper end. The rotating body 55 is rotatably supported by a shaft 56, and an eccentric cam 57 is in contact with the rear surface of the rising portion 55a.

The eccentric cam 57 has a rotating shaft 60 supported by bearings 59 and 59 '.
Is attached to. The rotating shaft 60 has a pair of rotating plates 62,6.
2'is attached, and a claw 63 is provided on the rotary plate at a position eccentric to the rotary shaft.

The rotary power of the motor 67 is transmitted to the rotary shaft 60 via the pulley and the belt 65. When the rotation shaft 60 rotates and the long diameter portion of the eccentric cam 57 presses the rising portion of the rotating body 55, the rotating body rotates, and the horizontal portion 55b pushes the transmission shaft 52 downward.
Therefore, the rotating arm 37 rotates downward and presses the rear end portion of the lever 33, so that the lever 33 rotates about the fulcrum 32 and the indenter holder 29 is lifted. When the short diameter portion of the eccentric cam 57 is in contact with the rotating body 55, the indenter holder 29 is in a lowered state.

A weight cover 69 is provided above the weight 15, and an upper end portion of the hollow shaft 20 projects above the weight cover, and a pair of shafts 70 and 70 'sandwich the hollow shaft. It is installed side by side. The shafts 70, 70 'are rotatably supported,
On both sides of the hollow pipe 20 in the middle thereof, engaging members 71 that engage with the upper projections 21 of the hollow pipe from below are provided, respectively. An arm 73 with which the claws 63 of the rotary plates 62, 62 'abut is provided at the rear end of the shafts 70, 70', and the shafts 70, 70 'are provided with an engaging member 71 for the upper projection 21 of the hollow shaft 20. A spring 74 is provided for urging the spring 74 so that the spring 74 is not engaged with. The rotating shaft 60 rotates and the rotating plates 62,6
When the 2 ′ claws 63, 63 press the arms 73, 73, respectively, the shaft 7
0, 70 'rotates against the tension of the springs 74, 74, and the engaging member 71
Engages with the upper protrusion 21 of the hollow shaft 20 and pushes it up, so that the hollow shaft 20 that is normally placed on the load transmission shaft 25 moves upward while lifting the weight group. Therefore, no load is applied to the indenter. Axis 70,7 above
0 ', the engaging member 71, the arm 73, the spring 74, etc. constitute a load lifting device D for temporarily stopping the load function of the weight.

The rotary plates 62, 62 'and the eccentric cam 57 have a common rotary shaft 60.
Since the load adding / removing device C and the load hoisting device D are interlocked with each other, when the indenter 30 is hoisted, the weight is hoisted at the same time.

The load device A is provided with a load switching device E for switching the magnitude of the load applied to the indenter 30.
The load switching device E includes a load group 15, ...
It has a pair of backing plates 77, 77 that move forward and backward on the lower side to support the load. The receiving plate 77 has a curved notch 78 formed along the outer periphery of the cylindrical load 15 at the center, and both ends thereof are fixed to the nut members 80, 80. The nut members 80, 80 are
It is screwed onto a pair of screw rods 81, 81 having screws opposite to each other on both sides of the central portion. When the screw rods 81, 81 simultaneously rotate in the same direction by the rotational power transmitted from the drive motor 83 via the belts 84, 84 ', the nut members 80, ... Backing plate 77,77
Move toward each other or away from each other according to the rotation direction of the motor 83. When the pair of receiving plates 77, 77 move toward each other, that is, toward the hollow shaft 20 that suspends a load, the number of weights supported by the receiving plates 77, 77 increases when the hollow shaft 20 descends. The load value applied to the indenter 30 is reduced. On the contrary, when the receiving plates 77, 77 move away from each other, the weight located at the center is not supported, and the load applied to the indenter 30 increases. Backing plate
When 77, 77 move to the outermost part, all weights become free, and the maximum load (for example, 2000 grf) is applied to the indenter 30. Further, when the receiving plates 77, 77 are closest to each other, all weights up to the minimum weight 15h are supported by the receiving plates, so that only the weight of the hollow shaft 20 is loaded on the load transmission shaft 25. It will be. That is, the hollow shaft 20 itself acts as one weight. Further, since the weight of the indenter holder 29, the load transmission shaft 25, the lever 33, and the like is added to the indenter 30, these also constitute one of the separately provided weights. In this case, the weight of the hollow shaft 20 and the indenter holder 29
It is preferable that the total weight of the weights is lighter than the weight of the minimum weight 15h. For example, if the minimum test load is 5g, the load on the indenter holder 29, load transmission shaft 25, lever 33, etc.
5 g, and the weight of the hollow shaft 20 may be 5 g. Since the weight of the weight group is added to the hollow shaft 20, it is necessary to have sufficient strength to support the weight. Therefore, it is preferable that the hollow shaft 20 is made of a light alloy or the like. With this load device, for example, it is possible to switch 11 steps in a load range of 5 to 2000 grf.

The load switching screw rods 81, 81 may be manually rotated by providing a knob instead of the power of the motor.

Next, the optical device B will be described. This micro hardness tester is equipped with a pipe 90 that serves as an optical path in the front-rear direction.
A lamp 91 serving as a light source is provided at the rear end of the lamp. A half mirror 93 is attached to the front end of a pipe 90 passing through the upper part of the load device A, and a prism 95 is arranged above it. The front end of the prism 95 faces the optical path tube 99 of the measuring instrument 98 to which the eyepiece lens 97 is attached.

The hollow shaft 20 is located just below the half mirror 93, and the optical axes to the objective lenses 45 and 46 pass through the hollow shaft 20. Illumination light from the light source 91 passes through the pipe 90 and the half mirror 93 along the optical axis L, and is guided to the surface of the sample along the optical axis M in the hollow shaft 20. Further, the reflected light from the surface of the sample passes through the half mirror 93 from the objective lever 45 (46) through the optical axis M of the hollow shaft 20 and reaches the prism 95. Then, it is bent and guided to the eyepiece lens 97 along the optical axis S.

Explaining how to use this micro hardness tester, first, a test piece, which is a test piece, is fixed to the stage 10 of the sample table 2, the vertical position is adjusted by the handle 3, and the micrometer heads 8 and 8'are operated. Select the test location. At this time, the observation objective lens 46 is positioned immediately below the hollow shaft 20.

After the test point is determined, the load case 27 is rotated to set the indenter 30 at the test position immediately below the hollow shaft 20. At this time, the load adding / removing device C is operated in advance to rotate the rotating body at the long diameter portion of the eccentric cam 57.
Rotate 55 downward, push down the transmission shaft 52, and lift the indenter from the surface of the test piece. Since the load adding / removing device C and the load hoisting device D are interlocked with each other, in this state, the hollow shaft 20 moves upward to hoist and support the weight group.

Next, the load switching device E is driven so that the load applied to the indenter becomes a desired load. Then, if the load adding / removing device C and the load lifting device D are released, the weight 1
The loads of 5, ... Are transmitted to the force application point (point 25a) of the indenter holder 29 via the hollow shaft 20 and the load transmission shaft 25, and the indenter 30 is pushed into the test surface.

When the pushing of the indenter is completed, the load adding / removing device C and the load lifting device D are operated again to lift the indenter 30 and the weights 15, ..., The load case 27 is rotated, and the objective lens 46 is positioned at the test position. The size of the indentation is measured by the measuring device 98 while observing the image of the indentation with the eyepiece lens 97.

[Effects of the Invention] As is clear from the above description, in the micro hardness tester according to the present invention, the weight of the loading device loaded on the indenter has the through hole through which the optical axis of the optical device is formed, Even if the direct loading method in which the weight is placed on the load axis is adopted, it no longer interferes with the optical system. Therefore, the structure of the optical device can be simplified even if the number of weights is increased.

[Brief description of drawings]

1 is an external view of a micro hardness tester showing an embodiment of the present invention, FIG. 2 is a side sectional view thereof, FIG. 3 is a sectional view of an indenter holder thereof, FIG. 4 is a plan view of a measuring section, and FIG. The figure is a front view thereof. 1 ... Micro hardness tester, 9 ... Measuring part, 15 ... Weight 20 ... Hollow shaft, 25 ... Load transmission shaft, 29 ... Indenter holder 30 ... Indenter, 33 ... Lever, 45, 46 ... Objective lens 97 ... Eyepiece lens, A … Load device, B… Optical device

Claims (1)

[Claims] 1. A micro hardness tester comprising an indenter pushed into a test piece, a load device for applying a load of a weight to the indenter, and an optical device capable of observing a test point on the surface of the test piece, A micro hardness tester, wherein a through hole through which an optical axis of an optical device passes is formed in a weight of the load device.