JPS6236829Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a device for creating a glass blade in a microtome for creating specimen sections for an electron microscope.

In a transmission electron microscope, it is necessary to prepare a sample through which an electron beam can pass, so various ultrathin section preparation techniques and devices have been developed and put into practice. A microtome is one example, an indispensable tool for creating ultrathin sections of biological samples. The most important thing in sample cutting with this microtome is the cutting blade, and conventionally a sharp blade obtained by breaking glass is used. The glass blades are made manually using a glass cutter made of diamond or the like, but obtaining a good blade requires great skill and is a rather troublesome task for an amateur.

To solve this problem, glass knife making machines have been commercially available. Its structure is shown in FIG. In the figure, 1 is the base of the device, which is formed into a box shape. A holder 2 integrated with the base at one end is fixed on the base,
A cutter 4 including a glass cutter (cutting tool) 3 made of diamond, cemented carbide, etc. on this holding body
is held slidably in the direction of the arrow. The holding body has two first protrusions 5a and 5b symmetrically arranged in a direction perpendicular to the cutting line made by the cutter.
(5b not shown) is provided facing downward, and the glass plate 6 is pressed against this. This glass plate is held on the base 1 so as to face the glass cutter, and the glass plate holding portion of the base has a slot 7 elongated in the direction of the glass cutting line.
is provided, and second protrusions 8a, 8b are inserted upward into these holes. This protrusion is placed directly below the cutting line made by the cutter, and is pushed upward by a pressing mechanism 9 using a lever or the like.

In such a configuration, the glass plate 6 is attached to the base 1
After setting the glass cutter 4 on the glass, push the glass cutter 4 in the direction of the arrow or cut a cutting line on the top surface of the glass. Thereafter, when the pressing mechanism 9 is driven to push up the second protrusions 8a and 8b, the upper surface of the glass plate 6 is supported by the first protrusions 5a and 5b, and the lower surface of the center of the support point is in a direction perpendicular to the first protrusions 5a and 5b. Since it is pressed by the second protrusions 8a and 8b, it is broken along the cutting line, and a sharp blade is formed at the end of the break.

However, a device having such a configuration has many problems and is not completely satisfactory in practical terms. First, as shown in the schematic diagram in Fig. 2, the holder 2 has a cantilevered structure against the pressing force (load) W, so it has a mechanical structure similar to the cantilever beam in Fig. 3. This creates a large bending moment and deflection, making it difficult to sharpen the blade accurately and making it difficult to cut thick glass plates. That is, in Fig. 3, when the length of the cantilever beam is l, the load is W, the modulus of longitudinal elasticity of the material is E, and the moment of inertia of area is I, the bending moment M and the deflection δ are respectively M=Wl δ= Wl ³ /3EI. It can be seen that this exhibits a large bending moment and deflection relative to the beams supported at both ends as shown in various figures in FIG.

Figure 4a shows a beam with free ends, b shows a beam with one end free and the other fixed, and c shows a beam with both ends fixed.
The bending moment and deflection of each beam are as follows.

(a) M=Wl/2, δ=Wl ³ /6WI (b) M=2Wl/5.3, δ=El ³ /13.5EI (c) M=Wl/4, δ=Wl ³ /24EI Comparison of the above equations With more conventional equipment, the bending moment M is 2 to 4 times larger than the support at both ends, and the deflection δ is 2 to 8 times larger, which poses a major problem in the structure of the equipment and limits the load, making it difficult to cut thick glass plates. cannot be used for Also, related to the large deflection, cantilevered beams are susceptible to vibrations, and the glass fracture surface may become wavy due to the vibrations, which often makes it impossible to obtain a good glass blade. Furthermore, as shown in FIG. 5, the holder 2 gets in the way when setting the glass plate on the substrate, and the glass plate is observed from an oblique direction at an angle θ. Accurate settings are difficult, making it difficult for amateurs to obtain a good glass blade.

The purpose of this invention is to eliminate the drawbacks of the above-mentioned conventional example, and its basic structure is to use a beam supported at both ends as shown in Figure 4, thereby reducing the bending moment. and a device for making a glass blade for a microtome that can reduce deflection.

FIG. 6 is a diagram showing the basic type of the present invention, and is drawn corresponding to the conventional FIG. 2. In the figure, reference numeral 10 denotes a rotation shaft, which is provided to penetrate one end of the holder 2 and supports the holder 2 so as to be rotatable at least about 90 degrees as indicated by the arrow in the figure. The direction of the rotation axis is perpendicular to the direction of the cutting line made by the glass cutter (it is not limited to this direction, and may be, for example, a direction perpendicular to the axis). A hook 11 is provided at the other end of the holder, and is engageable with a hook 12 provided on the upper part of the base body 1. Both hooks are attached when the holder is in the state shown, that is, when the glass plate 6
When the first protrusions 5a and 5b are pressed, they are firmly integrated, and when setting the glass plate 6, the engagement between both hooks can be released by operating the hooks 11 or 12. It is. With this, when creating the glass blade, it will be in the state shown in Figure 6,
A load W is applied to the glass plate 6 by a second protrusion (not shown) to break the glass plate. In this state, the holder 2 is supported at both ends of the rotating shaft 10 and the hooks 11 and 12, so the structure is similar to that of the beam fixed or supported at both ends in c or b of FIG. 4, and the holder 2 is supported by the bending moment M becomes smaller, and the deflection δ also becomes significantly smaller. On the other hand, when setting a glass plate, after releasing the engagement between the hooks 11 and 12, the holder 2 is rotated in the direction of the arrow to remove the holder from the upper part of the base. This makes it possible to set the glass plate while observing the glass plate from directly above, as shown in FIG. 7, making the setting of the glass plate extremely accurate and extremely easy to handle.

8 and 9 show the completed embodiment, with FIG. 8 being a plan view and FIG. 9 being a longitudinal sectional view.
In the figure, X-X indicates the direction of the cutting line, and the first protrusion 5
a and 5b are symmetrically provided in a direction orthogonal to the line XX. The glass cutter 4 is guided by a guide body 13, which is connected to the holder 2.
It is slidable in the vertical direction and can be moved up and down by an adjustment screw 14. That is, when the adjustment screw 14 is rotated to the right, the guide body 13 moves upward, and when it is rotated in the opposite direction, the guide body descends, and the glass cutter 4 and the first protrusions 5a and 5b move up and down. do. This allows the cutting position to be set correctly even if the thickness of the glass changes. 8 is a second protrusion, but in this embodiment, two protrusions are not used, but a single semi-cylindrical protrusion is used. The shape of this protrusion is not particularly important, as long as it presses at least two points in the direction of the cutting line. The projection is pressed by a lever 9, which is driven by the rotation of a drive handle designated by the reference numeral 15 in FIG. 16a and 16b are bearings for the rotating shaft 10. The hook 11 is normally rotated in the direction of the arrow by a coil spring or the like, and therefore is normally in a state of engagement with the other hook 12.
When the upper end of the hook 11 is rotated in the direction opposite to the arrow, the hook is detached from the hook 12.

With the configuration described in detail above, the holder 2 is connected to the rotating shaft 10 and the hook 11 during the glass plate cutting operation.
and 12 are supported at both ends and integrated with the base body 1, so when the second protrusion 8 or 8a, 8b is pressed against the glass plate 6, a bending moment W similar to that of the beam supported at both ends shown in FIG. The deflection δ is extremely small compared to the conventional cantilever case. Therefore, a small and strong device can be obtained, even thick glass plates can be easily broken, and since there is little vibration, the broken surface will not be wavy, and a good glass blade can be obtained. Furthermore, since the glass blade can be set while rotating the cutter holder, it is possible to set the position of the glass blade while observing it from directly above, allowing extremely accurate setting.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing the configuration of a conventional device;
3 is a diagram showing an outline of the conventional device, FIG. 3 is a diagram showing a beam showing the structural features of the conventional device in FIG. 1, and FIG.
The figures show a beam supported at both ends corresponding to Fig. 3, Fig. 5 shows the drawbacks of the conventional device shown in Fig. 1, Fig. 6 shows a schematic configuration of the present invention, and Fig. 7. is the fifth
8 is a plan view of a completed embodiment of the present invention, and FIG. 9 is a longitudinal cross-sectional view of the same. 1: Base, 2: Holder, 4: Glass cutter,
5a, 5b: first protrusion, 6: glass plate, 8, 8
a, 8b: second protrusion, 9: second protrusion pressing mechanism, 10: rotating shaft, 11, 12: hook, 13:
Cutter guide body, 14: Adjustment screw, 15: Handle of pressing mechanism, 16a, 16b: Bearing.

Claims (1)

[Scope of utility model registration request] A cutter for cutting glass, a means for moving the cutter along a straight line, and at least two cutters that sandwich the line to be cut by the cutter and come into contact with the upper surface of the glass plate.
a first protruding member, a holder holding the cutter and the first protruding member, a second protruding member placed on the line where the glass is to be cut and abutting the lower surface of the glass plate;
A device comprising a protruding member, a mechanism for pressing the second protruding member against a glass surface, and a base body holding the glass plate and accommodating the second protruding member, the cutter and the first protruding member being held. One end of the holder is rotatably held, and the base body and the holder are firmly integrated on the side opposite to the rotation axis by sandwiching the first protruding member, and the integration can be easily performed. A glass blade making device for a microtome, which is provided with an engaging means that can be separated.