JP7766345B2 - Microscope heating device - Google Patents

Description

The present invention relates to a microscope warming device suitable for maintaining a specimen, such as a cell, at an appropriate temperature when the specimen is placed in a culture vessel on the microscope stage.

To enable microscopic observation of specimens such as cells while culturing them in a culture vessel, the conventional approach has been to focus on the space above the stage, surrounding the culture vessel placed on the stage from above with a so-called heat-insulating box and heating the space inside the box. Patent Document 1 and Non-Patent Document 1 propose heating outside air with a heater and then blowing the warm air into the box using a fan or duct.

Publication number 03-025598 Japanese Patent Application Laid-Open No. 2003-107364

Incubator NL Ti2 BLACK 2000, PECon GmbH - Specialist for Cell and Tissue Culture Systems on the Microscope [Retrieved July 13, 2022], Internet <https://www. pecon. biz/products/product/? pid=5390 | incubator_NL_Ti2_BLACK_2000> Objective Heater S, PeCon GmbH - Specialist for Cell and Tissue Culture Systems on the Microscope [Retrieved July 13, 2022], Internet <https://www. pecon. biz/products/product/? pid=5354%7CObjective_Heater_S>

The stage has an opening (transmission window) through which the bottom of the culture vessel containing the specimen is exposed to the underside of the stage. Therefore, with the methods of heat retention described in Patent Document 1 and Non-Patent Document 1, the specimen placed on the inner bottom surface of the culture vessel is easily affected by room temperature, and when the room temperature is low, the culture vessel is not sufficiently kept warm.
Furthermore, as for the simplified type, instead of using an insulated box, there is a closed incubator housing the culture vessels and providing a heater function to ensure a warm state, as described in Patent Document 2. Each incubator is compactly placed on a stage, and is used as an insulated box type depending on the application. However, even with this type, the bottom of the culture vessel containing the specimen is exposed toward the underside of the stage. Therefore, as with the above, specimens placed on the inner bottom surface of the culture vessel are easily affected by room temperature.

In particular, when observing a specimen at high magnification with an inverted microscope or when using oil or water immersion, the objective lens comes extremely close to or touches the underside of the bottom of the culture vessel exposed at the opening in the stage, and therefore, when the room temperature is low, heat is more likely to be lost by the cooled objective lens.
In response to this issue, Non-Patent Document 2 proposes attaching an external lens heater to the objective lens to directly heat the objective lens. However, because heat is transferred directly from the side in contact with the lens heater, temperature differences are likely to occur in the objective lens. A sudden drop in room temperature can exacerbate these differences, risking damage to lenses that are sensitive to temperature changes. Furthermore, because the heater is externally attached to match the lens diameter of the objective lens, it lacks versatility. Furthermore, for ease of observation, a revolver is typically equipped with at least two types of objective lenses, one with high magnification and one with low magnification. Rotating the revolver with a lens heater attached to each objective lens can tangle the lens heater cord. Additionally, in the case of objective lenses with correction collars, attaching a lens heater makes it difficult to operate the correction collar.

Demands for precision in microscopic observations are increasing year by year, and the purpose of this invention is to overcome the above-mentioned challenges and provide a microscope warming device suitable for maintaining specimens such as cells in an appropriate warm state when the culture vessel containing the specimen is placed on the microscope stage.

The present invention was made to solve the above-mentioned problems, and provides a microscope warming device comprising: a cover that surrounds the space extending from the opening of a microscope stage to the lens located below it, and that creates a closed space together with the bottom of a container placed on the stage and closing the opening; a temperature sensor that detects the temperature of the closed space; and a circulating hot air blowing mechanism that blows hot air toward the closed space. The closed space is heated by the hot air blown from the hot air blowing mechanism based on sensor information from the temperature sensor, and the specimen inside the container is kept warm via the bottom of the container.

Preferably, the stage has a plate-shaped mounting portion surrounding the plate surface, and the cover and the case of the hot air blowing mechanism are mounted to the mounting portion from below while communicating with each other in the lateral direction.
More preferably, the warm air blowing mechanism is configured to include a blower for circulating air inside the case, a fin-type heat sink provided on the suction side of the blower and dissipating heat to the air that passes through the fins, and a buffer chamber interposed between the blower and the heat sink, and the blower serves not only as an air blowing means but also as a negative pressure applying means for applying negative pressure to the buffer chamber.
More preferably, the blower is vibration-isolatingly connected to the mounting portion.
Even more preferably, the blower and the partition wall that defines the buffer chamber and surrounds the heat sink are stacked vertically and supported in an integrated manner by a block of vibration-damping material that is erected inside the case.
More preferably, a pair of heat sinks are arranged back to back with the heat generating element sandwiched between them, and the air flow path is serpentine.

The microscope heat insulating device can be configured such that the mounting portion is the bottom portion and further includes a heat insulating box that surrounds the upper part of the microscope including the stage.
Preferably, a heater panel is joined to the inner surfaces of the bottom and side surfaces of the heat-insulating box, and the upper surface of the heater forms a flat mounting surface.
Preferably, the side and top surfaces of the heat-insulating box are formed from an aluminum composite material in which a foamed polyethylene resin sheet is sandwiched between thin aluminum plates.

The microscope heating device of the present invention is suitable for installation on an inverted microscope, which is susceptible to heat loss by the objective lens. In this case, the cover creates an enclosed space that includes the nosepiece.

By attaching the microscope warming device of the present invention to a microscope and placing a culture vessel on the microscope stage, the specimen can be maintained at an appropriate temperature.

1 is a perspective view showing a state in which a microscope heat insulating device according to a first embodiment of the present invention is assembled to a microscope. FIG. 2 is a perspective view of the lower part of the microscope stage of the microscope warming device of FIG. 1. FIG. 2 is a front view of the microscope heat insulating device of FIG. 1. This is a perspective view of FIG. 1 with the heat insulating box omitted. FIG. 5 is an enlarged perspective view of FIG. 4 with a portion omitted. FIG. 6 is a perspective view of the hot air blowing mechanism of FIG. 5 . FIG. 7 is an exploded perspective view of the hot air blowing mechanism of FIG. 6. FIG. 7 is a vertical cross-sectional view of the hot air blowing mechanism of FIG. 6 . FIG. 2 is a perspective view showing a state in which a culture vessel is kept warm using the microscope warming device of FIG. 1. FIG. 10 is an image diagram of warm air generated in the lower space of the culture vessel in FIG. 9 . FIG. 11 is an image diagram of hot air shown from a different direction from that of FIG. 10 . 2 shows analytical data of the temperature distribution when the microscope warming device of FIG. 1 is used. 3 is a perspective view of the heater panel of FIG. 2 and a cross-sectional view of an aluminum composite material. FIG. 10 is an explanatory diagram of an example of use of the humidifying bottle. FIG. 10 is a perspective view showing a state in which a microscope heat insulating device according to a second embodiment of the present invention is attached to a microscope.

A microscope warming device 1 according to a first embodiment of the present invention will be described with reference to the drawings.
1 to 5, the microscope warming device 1 is a type that is assembled to an inverted microscope A, and is assembled by supporting a base plate 3 as a plate-shaped mounting part on a pair of brackets 5, 5 with the plate surface facing up and down. A large opening 7 is provided in the base plate 3 between the pair of brackets 5, 5, and in the assembled state, the plate surface of the stage B of the inverted microscope A is surrounded by this opening 7. Part of the edge of the opening 7 serves as a contact part, which absorbs play.
The surface of the base plate 3 is a horizontally long rectangle, with the longer sides extending in the left-right direction across the brackets 5, 5 for mounting the microscope.

A cover 9 is attached to the underside of this base plate 3. This cover 9 is shaped like a flat, bottomed square box, with the upper edge of its side portion 9a fixed to the base plate 3. This cover 9 also has an opening 11 in the center of its bottom portion 9b, surrounding the inverted microscope A. The edge of the opening 11 forms a contact portion, which contacts the underside of the objective lens C against the inverted microscope A, closing the gap with the inverted microscope A side. This contact portion is located below the nosepiece D, and the cover 9 is positioned so that it covers from below the space extending from the opening of stage B to the objective lens C and further to the nosepiece D.

The bottom surface 9b of the cover 9 is rectangular in shape, with the left-right direction longer than the front-to-back direction. As shown in Figure 5, the front corner of one of the left and right side surfaces 9a is missing a rectangular corner. At this corner, the entire inner left-right side of the side surface 9a is open, and the upper half of the rear surface is open. A small case 15 is attached to this open corner 13 so that the corner fits into it. The case 15 is shaped like a square box with a bottom. The case 15 is attached to the base plate 3 in the same way as the cover 9. The side surface 15a of this case 15 facing the cover 9 is also open, forming a communication port 17 that connects laterally to the cover 9. The case 15 is roughly square when viewed from above, and the bottom surface 15b is at approximately the same height as the bottom surface 9b of the cover 9.

The hot air blowing mechanism 19 is configured by providing various parts inside the case 15 .
As shown in FIGS. 6 to 8, spacer pillars 23, 23, 23, 23 (the one on the front side is not shown) rise from the four corners of a substantially square fixing plate 21, and the upper end of each spacer pillar 23 is attached to a nut 25.
Reference numeral 27 denotes a rectangular vibration-isolating block made of vibration-isolating gel made of silicone resin. The vibration-isolating block 27 is arranged in an upright position with its larger plate surface facing horizontally between the opposing spacer columns 23, 23 on one edge side of the fixed plate 21. A pair of vibration-isolating blocks 27, 27 are arranged opposite each other.

A mounting plate 29 is installed across the upper end surfaces of the opposing vibration isolation blocks 27, 27. The opposing edges of the mounting plate 29 are bent in two stages at approximately right angles to form stepped surfaces 29a, each of which is lowered by one step. A circular opening 29b is also provided in the center.
Each vibration-damping block 27 is positioned between the lower surface of this step surface 29a and the upper surface of the fixed plate 21, and the upper surface of the vibration-damping block 27 is pressed against the lower surface of the step surface 29a, and the lower surface is pressed against the upper surface of the fixed plate 21 by appropriate means.

The mounting plate 29 is spanned by vibration-isolating blocks 27, 27 in a beam-like manner, and the space below the opening 29b is open, to which a buffer frame 31 and a base frame 33 are fixed from below. Both the buffer frame 31 and the base frame 33 are rectangular with a bottom, and the outer surfaces of the planes perpendicular to the vertical direction are the same size and are approximately rectangular.
As shown in the top view enclosed by a circle, the buffer frame 31 has an oval ventilation hole 31b formed along one corner of the bottom surface 31a.
The base frame 33 is also provided with an oval ventilation hole 33b along the lower corner of one of the side surfaces 33a.

The buffer frame 31 is stacked on the base frame 33 with the outer surfaces of the buffer frame 31 aligned, and is fixed to the mounting plate 29 with screws, so that the buffer frame 31 and the base frame 33 are hung integrally.
In this suspended state, a small gap 34 remains between the bottom surface of the lower base frame 33 and the top surface of the fixed plate 21. In addition, the ventilation hole 31b on the buffer frame 31 side and the ventilation hole 33b on the base frame 33 side are positioned in the same direction.
The upper opening of the base frame 33 is closed by the bottom surface 31a of the buffer frame 31, and communicates with the buffer frame 31 side via a ventilation hole 31b.
The upper opening of the buffer frame 31 is closed by the mounting plate 29 and communicates with the upper side of the mounting plate 29 via an opening 29 b of the mounting plate 29 .

A fin-type heat sink 35 is housed within the concave inner surface of the base frame 33. The heat sink 35 is composed of a support plate 35a and numerous heat dissipation fins 35b, 35b, ... erected on the upper surface of the support plate 35a. Each heat dissipation fin 35b is a rectangular flat plate that stands with its plate surface facing horizontally. The heat dissipation fins 35b, 35bb, ... are regularly arranged vertically and horizontally in a plane, with adjacent plate thicknesses facing each other with a narrow gap in one orthogonal direction, and adjacent plate surfaces facing each other with a wide gap in the other direction. These wide gaps are used as air circulation paths 37, allowing air to circulate as shown by the arrows.

Two heat sinks 35 are housed, and are stacked one on top of the other in the vertical direction with their support plates 35a, 35a facing back to back.
Each heat sink 35 is rectangular so as to be fitted into the concave inner surface of the base frame 33, and the air flow paths 37, 37, ... are housed in a direction perpendicular to the plate surface of the side surface portion 33a on the ventilation hole 33b side of the base frame 33. Therefore, the ventilation hole 33b communicates with the air flow paths 37, 37, ... of the heat sink 35 below.
A nichrome wire 39 is laid between the upper and lower support plates 35a, 35a as a heating element, and both the upper and lower support plates 35a, 35a are thermally connected to this nichrome wire 39, so that the lower and upper heat sinks 35, 35 have a heat dissipation function.
In order to ensure space for arranging the cord made of bundled nichrome wires 39, the upper heat sink 35 is slightly smaller in length than the lower heat sink 35, and a gap 41 is formed on the side of the hole through which the cord is passed.

A blower 43 for circulating air is placed on the upper surface of the mounting plate 29. The blower 43 is installed with its suction port facing the mounting plate 29, and an opening 29b of the mounting plate 29 communicates with the suction port of the blower 43.
Therefore, the upper opening of the buffer frame 31 is closed by the bottom surface of the blower 43 , thereby defining a buffer chamber 45 .
The outlet 43 a of the blower 43 faces the ventilation hole 33 b of the base frame 33 .

The fixing plate 21 of the hot air blowing mechanism 19 is placed on the bottom side and the blower 43 on the top side inside the case 15. The base plate 3 has a through hole, and the spacer column 23 is fixed to the base plate 3 with a screw by using the through hole and a nut 25 on the spacer column 23 side.
There is a small gap between the underside of the fixed plate 21 and the inner bottom surface of the case 15, and the buffer frame 31 and base frame 33 sides of the warm air blowing mechanism 19 are suspended from the base plate 3. In other words, the vibration-proof blocks 27, 27 support and lift up the blower 43 and the partition wall formed by the buffer frame 31 and base frame 33 in a vertically stacked and integrated state.

In the hot air blowing mechanism 19, when the blower 43 is motor-driven, the buffer chamber 45 becomes negative pressure, and as shown by the arrows in Figure 8, air is sucked in through the ventilation holes 33b of the base frame 33, flows through the air flow path 37 of the lower heat sink 35, is heated, then rises through the gap 41, passes through the air flow path 37 of the upper heat sink 35, and follows a serpentine path, being uniformly and sufficiently heated by the buffer effect, passes through the ventilation holes 31b, and flows into the buffer chamber 45. The air is then sucked into the suction port of the blower 43 and discharged as hot air at an appropriate volume from the discharge port 43a.
As described above, the blower 43 serves not only as an air blowing means but also as a negative pressure applying means for applying a negative pressure to the buffer chamber 45 .

2, 4, and 5, reference numeral 47 denotes a thermoelectric temperature sensor. A cord 47a of this temperature sensor 47 is inserted through a threading portion 9c provided in the cover 9. The tip of the cord 47a, which is the detection portion 47b, is fixed by a holder 49 inside the cover 9, and the detection portion 47b protrudes into the space inside the cover 9.
A controller (not shown) performs feedback control of the hot air blowing mechanism 19, and the amount of heat generated by the nichrome wire 39 increases or decreases based on sensor information from the temperature sensor 47, thereby changing the temperature of the hot air discharged from the blower 43.

The cover 9 surrounds the opening b1 of the stage B and the objective lens C together with the revolver D located at its base, and as shown in Figures 9 to 11, the opening b1 of the stage B is closed by the bottom e1 of the culture vessel E, such as a well plate, placed on the stage B, thereby forming a closed space 51 together with the bottom e1.
The orientation of the outlet 43a is adjusted, and as shown in Figures 10 and 11, the warm air is blown out from the side, as indicated by the arrow, toward the peripheral area of the nosepiece D below the objective lens C, which is particularly susceptible to room temperature. The warm air then hits the partitions that define the closed space 51 and the objective lens C, changing direction and becoming turbulent, slowing down its wind speed. It then mixes with the surrounding air, brushes against the outer surfaces of the nosepiece D and objective lens C, and rises toward the bottom e1. Therefore, there is calm warm air directly below the bottom e1.

In this way, the entire closed space 51 is heated by the hot air blown from the outlet 43a of the hot air blowing mechanism 19, and the optical components are gently heated evenly, even if multiple objective lenses C of various sizes are attached or if correction collars are used. The culture vessel E also receives heat through the bottom e1 and is heated. In addition, because there is no wind on the bottom e1 side, immersion-type objective lenses can also be used.
The hot air blowing mechanism 19 has the above-mentioned configuration, is small and lightweight, and can be installed near the stage B, while being highly efficient in blowing out a large volume of sufficiently heated air as hot air, making it possible to stably keep the above-mentioned lower space at an appropriate temperature without being affected by changes in room temperature.
FIG. 12 shows the experimental results of the temperature distribution, which confirms that the desired temperature control of 37° C. can be achieved even when the room temperature drops.

As shown in FIGS. 1 and 3, the base plate 3 is used as a bottom portion, and a heat insulating box 53 is also attached to the space above the stage B to form a closed space 55.
The heat insulating box 53 is in the shape of a square box, and its front portion has an outer door 53a and an inner door 53b.
A heater panel 57 made of a PTC heater is bonded to the base plate 3, which forms the bottom of the heat insulation box 53, and to the inner surface of the side surface 53c. As shown in Figure 13, the heater panel 57 is shaped to fit the shape of the inner surface of the heat insulation box 53, and the PTC heater that forms the material is a self-temperature-control type, which does not require complicated control from a controller and simplifies the control of the entire device.

The side surface 53 c and the top surface 53 d of the heat insulating box 53 are made of an aluminum composite material 59 .
This aluminum composite material 59 is made by sandwiching a foamed polyethylene resin sheet 59a between thin aluminum plates 59b, 59b with a urethane adhesive 59c interposed between them, and the surface is covered with a polyethylene film 59d. Compared to the rigid PVC material (specific gravity: 1.45, thermal conductivity: 0.16 w/(m·K)), which was the material used for conventional thermal box housings, the aluminum composite material 59 (specific gravity: 0.81 (45% lower), thermal conductivity: 0.118 w/(m·K) (16% lower)) has lower thermal conductivity and better heat retention. Furthermore, the aluminum composite material 59 is lighter and approximately 1.5 times more rigid.

By using this aluminum composite material 59 in combination with the heater panel 57, the enclosed space 55 can be maintained in an appropriate heat-retaining environment with almost no wind.
In the present invention, attention is first focused on the underside of stage B, and as described above, a hot air blowing mechanism 19 is installed as a heater to heat the underside under feedback control, but by also heating the upper side of stage B in this manner as an auxiliary measure, it becomes easier to maintain the specimen in the culture vessel E in an appropriate heat-retaining environment.

Since the heat insulating box 53 does not have any fans or air ducts, the closed space 55 can be made neat and spacious, and the entire space can be heated evenly and uniformly.
Therefore, there is ample space beyond the movable range of the stage, and the flat upper surface of the heater panel 57, which has a large heat capacity, can be used as a mounting surface, allowing another culture vessel E or a humidifying bottle 61 (FIG. 14) to be placed directly on top of it. In a culture environment, not only heat retention but also moisture retention are important factors, and if the humidifying bottle 61 is placed inside the insulated box 53, sufficient heat can be constantly and stably received from the bottom of the bottle, so the liquid in the bottle will spontaneously gasify and escape into the space through the ventilation hole 61a as shown by the arrow, automatically maintaining moisture.
On the other hand, the heat insulating box 53 can be made compact to a size that is approximately the same as the movable range of the stage plus a little more. In this way, the degree of freedom in designing the heat insulating box 53 is increased.
In addition, since the inverted microscope A is surrounded by a heat curtain, even if the outer door 53a and inner door 53b of the heat insulation box 53 are opened and the entire box is exposed, the temperature change is minimized and the heat insulation state is stably maintained.

In a microscope heat insulating device 63 according to the second embodiment of the present invention, as shown in FIG. 15, the heat insulating box 53 is not assembled, and the space above the stage B is open.
The culture vessel E is set in an incubator 65 such as that described in Patent Document 2. This incubator 65 is equipped with a transparent top plate 65a with a heat generating function, which heats the inside of the culture vessel E from above. In addition, an aluminum heating plate is joined to the part that abuts against the stage B, so that the abutting part can also be heated.
However, since the narrow space inside the incubator 65 is heated, the volumetric effect of the insulated box 53 cannot be obtained, and while the one using the insulated box 53 in the first embodiment is considered a high-precision type, the one in the second embodiment is a simple type.

Although the embodiments of the present invention have been described in detail above, the specific configuration is not limited to these embodiments, and the invention also includes design changes within the scope of the present invention without departing from the gist of the present invention.
For example, the vibration-proof connection can be established if a vibration-proof member is interposed between the base plate 3 and the blower 43 , so the blower 43 may be connected to the case 15 via a vibration-proof block 27 , for example.
In addition, in the first embodiment, a culture vessel E such as a well plate is placed on stage B, but if a more precise culture environment is desired, it is also possible to set it in an incubator 65 as shown in the second embodiment and then place this incubator 65 on stage B.

1...Microscope warming device (first embodiment)
DESCRIPTION OF SYMBOLS 3...Base plate 5...Bracket 7...Opening 9...Cover 9a...Side portion 9b...Bottom portion 9c...Through portion 11...Opening 13...Corner portion 15...Case 15a...Side portion 15b...Bottom portion 17...Communication port 19...Hot air blowing mechanism 21...Fixed plate 23...Spacer column 25...Nut 27...Vibration isolation block 29...Mounting plate 29a...Step surface 29b...Opening 31...Buffer frame 31a...Bottom portion 31b...Ventilation hole 33...Base frame 33a...Side portion 33b...Ventilation hole 34...Gap 35...Heat sink 35a...Support plate 35b...Heat dissipation fin 37...Air flow path 39...Nichrome wire 41...Gap 43...Blower 43a...Outlet 45...Buffer chamber 47...Temperature sensor 47a...Cord
47b...Detection unit 49...Holder 51...Closed space 53...Insulated box 53a...Outer door 53b...Inner door 53c...Side portion 53d...Top surface 55...Closed space 57...Heater panel 59...Aluminum composite material 59a...Polyethylene foam resin sheet 59b...Thin aluminum plate 59c...Urethane adhesive 59d...Polyethylene film 61...Humidifier bottle 61a...Ventilation hole 63...Microscope insulated device (second embodiment)
65... Incubator 65a... Top plate A... Inverted microscope B... Stage b1... Opening (of stage) C... Objective lens D... Nosepiece E... Incubation vessel e1... Bottom (of vessel)

Claims (6)

a cover that surrounds a space extending from the opening of the stage of the microscope to the lens located below the opening, and that forms a closed space together with the bottom of a container that is placed on the stage and closes the opening;
a temperature sensor that detects the temperature of the closed space;
A circulating hot air blowing mechanism is provided to blow hot air toward the closed space,
The closed space is heated by hot air blown from the hot air blowing mechanism based on sensor information from the temperature sensor, thereby maintaining the specimen in the container in a warm state through the bottom of the container.
a plate-shaped mounting portion that surrounds the stage in a plate surface direction;
The cover and the case of the hot air blowing mechanism are attached to the attachment portion from below while communicating with each other in the lateral direction,
The hot air blowing mechanism is configured to include, inside the case, a blower for circulating air, a fin-type heat sink provided on the suction side of the blower for radiating heat to air passing through the fins, and a buffer chamber interposed between the blower and the heat sink, and the blower serves not only as an air blowing means but also as a negative pressure applying means for applying a negative pressure to the buffer chamber,
the blower is connected to the mounting portion in a vibration-proof manner,
A heat insulation device for a microscope, characterized in that the blower and the partition wall portion that defines the buffer chamber and surrounds the heat sink are stacked vertically and supported in an integrated state by a block of vibration-damping material erected within the case . 2. The microscope warming device according to claim 1,
A heat insulating device for a microscope, characterized in that a pair of heat sinks are placed back to back with a heating element sandwiched between them, and the air circulation path is serpentine . 3. The microscope heat insulating device according to claim 1 or 2,
A heat insulating device for a microscope, characterized in that the mounting portion is the bottom portion and further comprising a heat insulating box surrounding the upper part of the microscope including the stage . 4. The microscope warming device according to claim 3,
1. A heat insulating device for a microscope, comprising: a heater panel joined to the inner surfaces of the bottom and side of a heat insulating box; and an upper surface of the heater serving as a flat mounting surface . 5. The microscope warming device according to claim 4,
A heat insulating device for a microscope, characterized in that the side and top surfaces of the heat insulating box are made of an aluminum composite material in which a foamed polyethylene resin sheet is sandwiched between thin aluminum plates . 6. The microscope warming device according to claim 5,
A heat insulating device for a microscope that is attached to an inverted microscope and whose cover creates a closed space including the revolver .