JP2878241B2 - How to protect from harsh environments - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for protecting electronic equipment, control equipment, and the like from harsh and harsh environments exceeding normally assumed conditions such as vibration, shock, and temperature range.

[0002]

2. Description of the Related Art Conventionally, electronic devices and control devices have made remarkable progress and development, and inexpensive and high-performance devices have been marketed. These state-of-the-art devices are generally for consumer use, and are guaranteed to operate in a temperature range that is premised on impacts during the distribution process and normal indoor use.

[0003] However, in an environment such as an industrial, aerospace, or military environment where the operating conditions of the device are more severe, such a general commercial device for consumer cannot be used. Devices that can be used in harsh environments should be designed in advance with specifications that match the harsh operating environment at the stage of device development, and operation should be confirmed by conducting reliability experiments to guarantee operation in harsh operating environments. Need to be kept. As a general reference technique, Japanese Utility Model Laid-Open No. 5-55019 is cited.

[0004]

The conventional equipment which can be used in a severe environment requires a longer development period than a general commercial product. Therefore, the latest technological progress cannot be reflected at the time of practical use. In addition, the number of production is less than mass-produced general commercial products,
Manufacturing costs increase significantly.

Further, for example, a liquid crystal display device (hereinafter referred to as "L
Devices such as "CD") are formed by enclosing a liquid crystal material between two glass plates having a relatively large area, and are inherently weak against impact. The operable temperature range is limited. Such L
CDs are in principle difficult to use in harsh environments.

An object of the present invention is to provide a method for protecting a device manufactured under a normal operating environment from a harsh environment so that the device can be operated in a harsh environment.

[0007]

SUMMARY OF THE INVENTION The present invention is a method of protecting a device operating under severer conditions than vibration, shock and temperature conditions assumed as an operating environment of the device from a severe environment. The electronic cooling and heating unit is mounted inside the inner box so that the equipment to be cooled is housed in an airtight inner box and the heat radiation and cooling section of the electronic cooling and heating unit that can switch between cooling and heating is exposed outside the inner box. Then, the air in the inner box can be circulated by the inner fan, and the outer fan that ventilates the heat radiation cooling section of the electronic cooling and heating unit is installed outside the inner box,
The inner box and the outer fan are suspended in the outer box by a spring that absorbs excessive shock for the device in the three orthogonal directions. Even if the temperature of the external environment changes outside the operating temperature range of the device, the inner box and the outer fan are suspended. This is a method for protecting against severe environments, wherein an electronic cooling / heating unit, an inner fan, and an outer fan are operated such that a temperature change in the inside is within an operating temperature range of the device.

According to the present invention, the equipment to be protected is housed in an airtight inner box, an electronic cooling / heating unit is mounted on the inner box, and an external fan that ventilates the heat radiation / cooling section of the electronic cooling / heating unit. To the outside of the inner box. Because the inner box is airtight,
Equipment can be protected from high humidity environments. The air in the inner box can be circulated by the inner fan. When the temperature change of the external environment is outside the operating temperature range of the device,
Since the electronic cooling and heating unit and the fan are operated so that the temperature change in the inner box is within the operating temperature range of the device, the device is protected from high and low temperatures. The inner box equipped with an electronic cooling and heating unit and a fan
The device, the electronic cooling and heating unit, the inner fan and the outer fan are protected from external impacts because they are suspended in the outer case by springs that absorb excessive impact for the devices in the three orthogonal directions.

Further, the present invention is a method of protecting a device operating under severer conditions than assumed as an operating environment of the device from a severe environment, wherein the device to be protected is housed in an airtight inner box. The electronic cooling and heating unit is mounted inside the inner box so that the heat radiation and cooling section of the electronic cooling and heating unit that can switch between cooling and heating is exposed outside the inner box. A fan that ventilates the cold part is attached to the outside of the inner box, and the inner box is suspended in the outer box by a spring that absorbs shocks in three orthogonal directions, and temperature changes in the external environment are outside the operating temperature range of the equipment. The electronic cooling / heating unit and fan are operated so that the temperature change in the inner box is within the operating temperature range of the equipment, and multiple thin metal wires for springs are twisted as a spring to absorb impact. Winding the stranded wire Using a shock mount which is attached to both sides of the axis in parallel with the axial direction, a holder for maintaining the winding pitch as an air-core coil is formed, one holder is attached to the inner box, and the other is This is a method for protecting against severe environments, wherein the holder is attached to an outer box.

According to the present invention, the equipment can be housed in an airtight inner box to protect it from severe shock and temperature environments. As the shock absorbing spring, a shock mount is used in which an air core coil is formed by winding a stranded wire composed of a plurality of thin metal wires for springs, and a holder for maintaining the winding pitch as the air core coil is mounted in parallel in the axial direction. Since it is used, the shock applied to the outer box can be sufficiently absorbed to protect the equipment in the inner box.

Further, the present invention is characterized in that the device to be protected is a liquid crystal display device.

Further, according to the present invention, since the liquid crystal display device can be protected from external shock or severe conditions of temperature, high-performance and high-performance display can be performed even in a severe environment.

[0013]

1 to 4 show a method of protecting an LCD from a harsh environment according to an embodiment of the present invention. 1 is a right side view, FIG. 2 is a front view, FIG. 3 is a plan view, and FIG. 4 is a rear view. The LCD 1 is housed in an airtight inner box. The inner box 2 is held in the outer box 3 with a space therebetween via a shock mount 4 capable of absorbing shocks in three orthogonal directions. An electronic cooling and heating unit 5 is mounted on the back side of the inner box 2. Air is supplied to the electronic cooling and heating unit 5 from an outer fan 7 in a fan case 6 attached to the rear side of the inner box 2. A front panel 8 is mounted on the front side of the outer box 3, and a drip-proof type function key 9 is provided below the front panel 8. A handle 10 is attached to an intermediate portion of the front panel 8, and the outer box 3
As a whole can be attached to and detached from a rack or the like. A plurality of connectors 11, 12, and 13 are provided on the back side as shown in FIG. 4, and external signals and power can be connected. A large opening 15 is provided in the rear panel 14, and ventilation holes 16 are formed near both sides at the center.

FIG. 5 shows a cross section taken along the line VV of FIG. Since there is a space between the inner box 2 and the outer box 3, it is possible to mount the heat insulating material 17 around the inner box 2. A transparent cover 18 made of a transparent synthetic resin material is attached to an opening at the front of the front panel 8. A bezel 19 is attached to the inside of the transparent cover 18, and the inner box 2
The gap between the outer box 3 is hidden from the front side. On the front surface of the LCD 1, an upper cover 21 and a lower cover 22 made of transparent glass are provided via a spacer 20. With this double glass structure, the heat insulating property is improved. Lower cover 22
Is provided with a transparent inner panel 23 made of synthetic resin. A cushion 24 is mounted outside the upper cover 21 and the lower cover 22. The LCD 1 has a bolt 27 with respect to the inner panel 23 via a spacer 25 and a support cylinder 26.
Fixed at. The fixing between the front panel 8 and the outer box 3 is performed with the gasket 29 and the panel frame 30 interposed.

6 to 13 show a state in which the outer box 3 has been removed. 6 is a right side view, FIG. 7 is a plan view, FIG. 8 is a front view,
FIG. 9 is a sectional view taken along the section line IX-IX of FIG.
0 is a cross-sectional view taken along line XX of FIG. 6, FIG. 11 is a rear view, and FIG. 12 is a state in which the rear panel 14 is removed from FIG. From the back to the side of the inner box 2,
Shock mounts 4 are attached to the four corners. One of the pair of holders 31 of the shock mount 4 is attached to the inner box 2 and the fan case 6, respectively. Holder 3
The other one is attached to the outer box 3. The inner box 2 is suspended in the outer box 3 by the shock mounts 4 at the four corners, so that it is possible to reduce the impact load in three orthogonal axial directions.

As shown in FIG. 9, the electronic cooling and heating unit 5 protrudes from the inside of the inner box 2 to the outside. The portion outside the inner box 2 can be cooled by the outer fan 7. The inner fan 2 circulates the cooled or heated air in the inner box 2 by the inner fan 32. The space between the inner box 2 and the fan case 6 is fixed by bolts 34 and nuts 35 via spacers 33.

As shown in FIG. 10, the inner fan 32 is mounted in the inner box 2 by a mounting plate 36. Inner fan 32
, The temperature in the inner box 2 can be made uniform. At this time, for example, as shown in FIG. 10, when a pair of inner fans 32 is provided in front and back, the direction of the flow of air formed by the inner fans 32 is reversed in the front and rear. Thereby, a circulating flow is formed in the sealed inner box 2.

Electric power from a power supply is supplied to the thermo-cooler 37 of the electronic cooling and heating unit 5 via relay connectors 38 and 39. An external current is supplied to the switching transistor 41 via the relay connector 40. The switching transistor 41 is mounted on a mounting plate 42.

As shown in FIG. 11, the rear cover 43 on the back side of the fan case 6 has an opening 44 through which the back of the electronic cooling and heating unit 5 is exposed to the outside, and a ventilation hole 45 for the outside fan 7. Each is formed. As shown in FIG. 12, when the rear cover 43 is removed, it can be seen that relay connectors 46 and 47 for supplying power to the outer fan 7 are arranged. When the outer fan 7 is provided on both sides of the electronic cooling and heating unit 5, the direction of air flow is adjusted so that the air flows in one direction.

FIG. 13 is a sectional view taken along the line XIII-XI in FIG.
2 shows a cross section viewed from II. The electronic cooling and heating unit 5 extending from the fan case 6 to the inner box 2 is provided with an inner cover 51 and an outer cover 52 with a base 50 interposed therebetween. The inner cover 51 is inserted into the inner box 2 and the inner fan 32
Cooling or warming the air flow generated by the The outer cover 52 is inserted into the fan case 6 and
Cooling or warming.

FIGS. 14 to 17 show the structure of the electronic cooling and heating unit 5. FIG. 14 is a plan view, FIG. 15 is a front view,
16 shows a right side view, and FIG. 17 shows a rear view. An inner heat sink 53 is housed in the inner cover 51, and an outer heat sink 54 is arranged in the outer cover 52. A mounting plate 55 is bonded to the back surface of the inner heat sink 53, and a mounting plate 56 is bonded to the back surface of the outer heat sink 54. The thermo cooler 37 is mounted between the mounting plate 55 and the mounting plate 56. A bush 57 for energization is also provided below the electronic cooling and heating unit 5.

FIG. 18 shows the structure of a thermocooler 37 used for the electronic cooling and heating unit 5. Thermo cooler 3
Numeral 7 is a flat plate, and has a cooling surface 60 and a heat radiating surface 6.
1 is a structure in which the cooling / heating element 62 is sandwiched, and when the polarity of the DC power supply connected via the lead wire 63 is reversed,
The cooling surface 60 and the heat radiation surface 61 are switched. That is, switching between cooling and heating is possible.

FIG. 19 shows the structure of the shock mount 4. The shock mount 4 is mounted so that the pair of holders 31 extend in the axial direction, and a stranded wire 64 formed by twisting metal wires such as stainless steel for spring is inserted into the insertion hole 65 to keep the pitch as an air-core coil constant. keep. Mounting holes 66 are formed at both ends in the axial direction of the holder 31, and are screwed to the inner case 2, the fan case 6, and the outer case 3, respectively. Since the shock mount 4 is wound on the air-core coil by the stranded wire 64 and the pitch is held by the holder 31, it is possible to buffer the impact force in the three orthogonal axial directions.

FIG. 20 shows an electrical configuration for temperature control according to the present embodiment. Input signals from an internal temperature sensor 71 for detecting the temperature inside the inner box 2 and an external temperature sensor 72 for detecting the temperature outside the inner box 2 are provided to a control circuit 70 implemented by a microcomputer or the like. / Digital conversion (hereinafter abbreviated as “A / D”) circuits 73 and 74 are input as digital values, respectively. The control circuit 70 operates the thermo-cooler 37 via the drive circuit 75 with reference to the output from the external temperature sensor 72 so that the temperature in the inner box 2 falls within the operating temperature range of the LCD. When the temperature difference between the inside and outside of the inner box 2 is large, the outer fan 7 and the inner fan 32 are also operated via the drive circuits 76 and 77. Thereby, the temperature change in the inner box 2 can be made smaller than the external environment, and the LCD 1 in the inner box 2 can be protected from severe temperature changes. The inner box 2 is airtight, so if it is dried first,
CD1 can also be protected from moisture. Table 1 below
Shows an example of a guaranteed environment for a typical LCD.

[0025]

[Table 1]

In FIG. 21, the operating temperature range guaranteed in Table 1 is shown by hatching. T1 is 40 for normal temperature T0
° C and T2 is 0 ° C. An LCD whose operation is guaranteed in such a temperature range is called a high temperature T3 and a low temperature T4.
A temperature cycle test is performed as shown in FIG. In order to further ensure reliability, a cycle of raising the temperature to a high temperature T5 is also included. In this test, a reliability test is performed assuming use under severe conditions, including a cycle of raising the temperature to a higher temperature T5. Although the LCD does not pass such a severe test at all, if the LCD has a double structure of the inner box 2 and the outer box 3 as in the present embodiment and the temperature inside the inner box 2 is controlled to protect the LCD, The range of temperature change in the inner box 2 is suppressed, and L
The CD is also within a temperature range where it can operate sufficiently.

An LCD is easily broken by a large impact because a liquid crystal material is sandwiched between glass plates. In the present embodiment, since the shock mount 4 can sufficiently absorb the shock, the LCD can be used even when an excessive shock force such as 500 G is applied.

In the above embodiments, the case where the LCD is protected from the harsh environment is described. However, semiconductor integrated circuits such as high-performance microprocessors and information processing equipment such as hard disks and printers are similarly protected. can do.

[0029]

As described above, according to the present invention, the equipment is housed in the airtight inner box, and the temperature change in the inner box and the excessive impact on the equipment are reduced by the temperature change and the impact of the external environment. In contrast, it is possible to alleviate the problem and protect the device. Thus, high-performance commercial equipment can be used even in a severe environment, and the manufacturing cost of a device used in a severe environment can be reduced.

Further, according to the present invention, it is possible to reduce a temperature change in the equipment housed in the airtight inner box. In addition, since the shock between the outer case and the inner case is absorbed by using a shock mount in which an air core coil is formed by winding a stranded wire, it is possible to effectively reduce the shock with a simple configuration.

Further, according to the present invention, since the liquid crystal display device can be used even in a severe environment, a versatile display which cannot be performed by individual lamps or meters can be performed. For example, monitoring and control can be performed for each of a plurality of systems, and the situation can be easily grasped. When an error occurs,
By displaying the cause and the procedure, a quick answer is possible. By eliminating individual instruments and display warning lights, the size of the device can be significantly reduced, and the manufacturing cost of the device can be reduced.

[Brief description of the drawings]

FIG. 1 is a right side view showing a configuration for protecting an LCD according to an embodiment of the present invention.

FIG. 2 is a front view of the configuration of FIG.

FIG. 3 is a plan view of the configuration of FIG. 1;

FIG. 4 is a rear view of the configuration of FIG. 1;

FIG. 5 is a cross-sectional view taken along the line VV of FIG. 2;

FIG. 6 is a side view in which an outer box is removed from the configuration of FIG. 1;

FIG. 7 is a plan view of the configuration of FIG. 6;

FIG. 8 is a front view of the configuration of FIG. 6;

FIG. 9 is a cross-sectional view as viewed from the section line IX-IX of FIG. 8;

FIG. 10 is a cross-sectional view taken along line XX of FIG. 6;

FIG. 11 is a rear view of the configuration of FIG. 6;

FIG. 12 is a rear view showing a state where a rear cover is removed from FIG. 11;

FIG. 13 is a sectional view taken along section line XIII-XIII in FIG. 9;

FIG. 14 is a plan view of the electronic cooling and heating unit 5;

FIG. 15 is a front view of FIG.

FIG. 16 is a right side view of FIG.

FIG. 17 is a rear view of FIG. 14;

FIG. 18 is a perspective view showing a configuration of a thermo module 37.

FIG. 19 is a perspective view showing the configuration of the shock mount 4.

FIG. 20 is a block diagram showing an electrical configuration for protecting the inside of the inner box 2 from a severe temperature change in the embodiment of the present invention.

FIG. 21 is a time chart showing an example of an environmental test.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 LCD 2 Inner box 3 Outer box 4 Shock mount 5 Electronic cooling and heating unit 6 Fan case 7 Outer fan 8 Front panel 9 Function key 14 Rear panel 17 Insulating material 21 Upper cover 22 Lower cover 23 Inner panel 24 Cushion 31 Holder 32 Fan 37 Thermocooler 50 Base 53 Inner heat sink 54 Outer heat sink 61 Heat radiating surface 62 Cooling element 64 Stranded wire 70 Control circuit 71 Internal temperature sensor 72 External temperature sensor

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G05D 23/00-23/32

Claims (3)

(57) [Claims] A method for protecting a device operating under severer conditions than vibration, shock and temperature conditions assumed as an operating environment of the device from a severe environment, wherein the device to be protected is placed in an airtight inner box. The electronic cooling and heating unit is mounted inside the inner box so that the heat radiation and cooling part of the electronic cooling and heating unit that can switch between cooling and heating is exposed outside the inner box, and the air in the inner box is removed. The inner fan can be circulated, and an external fan that ventilates the heat radiation and cooling section of the electronic cooling and heating unit is mounted outside the inner box. The inner box and outer fan are too large for the equipment in the three orthogonal orthogonal directions. Suspended inside the outer case with a spring that absorbs shock, electronically cooled so that the temperature change in the inner case is within the operating temperature range of the equipment even if the temperature change of the external environment is outside the operating temperature range of the equipment Heating unit, inner fan and outer A method of protecting against harsh environments, characterized by operating a fan. 2. A method for protecting a device operating under severer conditions than assumed as an operating environment of the device from a harsh environment, wherein the device to be protected is housed in an airtight inner box, and cooled. The electronic cooling / heating unit is mounted inside the inner box so that the heat radiation / cooling unit of the electronic cooling / heating unit that can switch heating is exposed outside the inner box. The ventilation fan is installed outside the inner box, and the inner box is suspended in the outer box by a spring that absorbs shocks in three orthogonal directions. The temperature change of the external environment is outside the operating temperature range of the equipment. Also, the electronic cooling and heating unit and the fan are operated so that the temperature change in the inner box is within the operating temperature range of the equipment, and a stranded wire consisting of multiple thin metal wires for springs is used as a spring to absorb impact. Wound to form air core coil And a holder for maintaining the winding pitch as an air core coil,
A method for protecting against harsh environments, characterized by using a shock mount mounted on both sides of the axis in parallel with the axial direction, mounting one holder on the inner box and mounting the other holder on the outer box. 3. The method according to claim 1, wherein the device to be protected is a liquid crystal display device.