Temperature Sensor

Abstract

To provide a small temperature sensor at a low price which enables the true temperature of the air outside a housing to be measured, without being affected by the heat of heat-generating components in the housing and the heat of walls with which the housing is in contact.SOLUTION: The temperature sensor comprises a casing 2 housing a temperature measurement element 3 and a heat-generating component 11, and a ventilating space 32 vertically extending inside the casing 2. The upper and lower ends of the ventilating space 32 communicate with the outside of the casing 2. The heat-generating component 11 is arranged at a position where an ascending air current is generated in the ventilating space 32 by the heat of this heat-generating component 11. The temperature measurement element 3 is arranged in such a manner that it detects the temperature of the air that is absorbed to the lower end of the ventilating space 32 due to the fact that an ascending air current is generated in the ventilating space 32.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a temperature sensor in which a temperature measuring element and a heat generating component are housed in a housing. [Background technology]

[0002] Conventionally, there are temperature sensors that detect the temperature inside a room. This type of temperature sensor is often attached to the wall surface inside a room. This wall-mounted type temperature sensor is sometimes formed to have a thin thickness so as to be less noticeable. If the housing of the temperature sensor is formed thin, the temperature measurement element provided in the housing cannot be separated from the wall surface, and the temperature measurement element is affected by the temperature of the wall and is also affected by the heat of the heat-generating components provided in the housing. Wall-mounted temperature sensors are installed in locations where air currents occur indoors, but when there is no air current, they may be measuring the temperature of stagnant air, or air affected by the heat of the walls or heat-generating components. For this reason, conventional temperature sensors reduce the power consumption of the electrical circuit to reduce the amount of heat generated, and place the temperature measurement element as far away as possible from the heat-generating components.

[0003] A technique for preventing a temperature measurement element from being affected by surrounding heat is described, for example, in Patent Document 1. Patent Document 1 discloses a temperature detection device in which a separate board is placed between a board having a heat-generating component and a board having a temperature measurement element, thereby increasing the thermal distance between the heat-generating component and the temperature measurement element and reducing the influence of the measurement. Furthermore, some conventional temperature sensors are configured to guide indoor air to a temperature measuring element by a fan. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5030816 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in a small temperature sensor such as a wall-mounted temperature sensor, there is a limit to how much thermal distance can be extended between the heat-generating component and the temperature measurement element, as described in Patent Document 1. In a small temperature sensor, even if a material with high thermal resistance, such as air, is interposed between the heat-generating component and the temperature measurement element, it is difficult to block the heat of the heat-generating component that is transferred to the temperature measurement element, and high-precision temperature measurement cannot be performed. This problem can be solved to some extent by using a fan to guide indoor air to the temperature measurement element. However, if this configuration is adopted, it becomes impossible to provide a small temperature sensor at a low price.

[0006] An object of the present invention is to provide a small, low-cost temperature sensor that can measure the true temperature of the air outside a housing without being affected by the heat of heat-generating components inside the housing or the heat of the walls that the housing contacts. [Means for solving the problem]

[0007] In order to achieve this object, the temperature sensor of the present invention comprises a housing that houses a temperature measuring element and a heat-generating component, and a ventilation space that is provided inside the housing and extends in a vertical direction while being separated from other spaces inside the housing, the lower and upper ends of the ventilation space are connected to the outside of the housing, the heat-generating component is positioned in a position where an ascending air current is generated in the ventilation space due to the heat of the heat-generating component, and the temperature measuring element is positioned so as to detect the temperature of air that is drawn into the lower end of the ventilation space due to the generation of the ascending air current.

[0008] In the temperature sensor of the present invention, the ventilation space may be formed by a duct provided inside the housing, and the duct may have a heat receiving portion that crosses over the heat-generating component so that heat is transferred from the heat-generating component.

[0009] In the temperature sensor of the present invention, the ventilation space may be formed by a duct provided inside the housing, and the heat-generating component may be disposed inside the duct.

[0010] In the temperature sensor of the present invention, the temperature measuring element and the heat generating component are mounted on a substrate, the housing has a base member supporting the substrate in an extending position in the vertical direction, and a cover member covering the base member including the substrate, and the inner surface of the cover member is provided with a pair of walls protruding toward the base member and extending in the vertical direction along a wall surface of the base member including the substrate, and the duct may be formed by the pair of walls, a portion of the cover member between the pair of walls, and the wall surface of the base member including the substrate. Effect of the Invention

[0011] According to the present invention, it is possible to provide a small, low-cost temperature sensor that can measure the true temperature outside a housing without being affected by the heat of heat-generating components inside the housing or the heat of the walls that the housing contacts. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a front view of a temperature sensor according to a first embodiment. [Diagram 2] FIG. 2 is a side view of the temperature sensor. [Diagram 3] FIG. 3 is a perspective view of the temperature sensor as viewed obliquely from the upper right. [Figure 4] FIG. 4 is a perspective view of the temperature sensor as viewed obliquely from below and to the left. [Diagram 5] FIG. 5 is an exploded perspective view of the temperature sensor. [Figure 6] FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. [Figure 7] FIG. 7 is a perspective view showing the inner surface of the cover member. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. [Figure 9]FIG. 9 is a cross-sectional view of the temperature sensor according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] (First embodiment) Hereinafter, one embodiment of a temperature sensor according to the present invention will be described in detail with reference to FIGS. 1 is a temperature sensor that is attached to a wall surface inside a room (not shown) and measures the temperature of the air around the housing 2 using a temperature measuring element 3 housed inside a box-shaped housing 2. The housing 2 comprises a base member 4 that is attached to a vertical wall of a room (not shown), and a cover member 5 that is attached to this base member 4. In the following, when indicating directions in explaining the configuration of this temperature sensor 1, the explanation will be given in the direction when looking at the temperature sensor 1 facing the temperature sensor 1 attached to the vertical wall.

[0014] The base member 4 is formed in a bottomed rectangular tube shape that opens toward the vertical wall (rearward). As shown in FIG. 5, the base member 4 according to this embodiment is formed of an attachment portion 4a that is placed on a vertical wall (not shown) and a base portion 4b that protrudes forward from the attachment portion 4a. A wall surface 6 that forms the front end of the base portion 4b extends in the up-down and left-right directions (horizontal direction) when the base member 4 is attached to the vertical wall. A substrate 7 is attached to this wall surface 6 so as to be aligned in parallel. Therefore, when the base member 4 is attached to the vertical wall, it supports the substrate 7 in a position that extends in the up-down direction.

[0015] The substrate 7 is mounted with a temperature measuring element 3, a heat generating component 11, and other electronic components (not shown). The temperature measuring element 3 is a component for detecting temperature, such as a resistance temperature detector, and is mounted on the lower end of one side of the substrate 7 in the left-right direction (the left side in FIG. 6). The heat generating component 11 is a component for a power supply circuit, and is mounted on the lower end of the other side of the substrate 7 in the left-right direction (the right side in FIG. 6) as shown in FIG. 6. In this embodiment, the temperature measuring element 3 and the heat generating component 11 are arranged so as to be distributed between one end side and the other end side of the substrate 7 in the left-right direction.

[0016] As shown in Figs. 3 to 5, the cover member 5 has a frame 12 attached to the base portion 4b in a stacked manner, pillars 13 to 16 protruding forward from the four corners of the frame 12, a front plate 17 provided at the front ends of the pillars 13 to 16, and first and second walls 18, 19 provided on a rear surface 17a (the inner surface of the cover member 5) of the front plate 17. When the cover member 5 is attached to the base member 4, the base member 4 including the substrate 7 is covered from the front by the cover member 5. As shown in Fig. 6, four openings 21 to 24 are formed between the frame 12 and the front plate 17, which are partitioned by the pillars 13 to 16. These openings are open upward, downward, leftward, and rightward.

[0017] The first wall 18 and the second wall 19 are each integrally formed with the front plate 17 by one-piece molding, protrude from the rear surface 17a of the front plate 17 toward the base member 4, and extend in the vertical direction along the inner surface 25 of the base member 4 including the substrate 7. The first wall 18 and the second wall 19 are spaced apart from each other in the vertical and horizontal directions at a predetermined interval, as shown in Fig. 6. The protruding ends (rear ends) of the first and second walls 18, 19 are formed so as to contact the substrate 7 or to follow the substrate 7 with a small gap formed between them, as shown in Fig. 8.

[0018] Therefore, by attaching the cover member 5 to the base member 4, a duct 31 (see FIG. 8) is formed inside the housing 2 by the first and second walls 18, 19, a portion 26 (see FIG. 7) between the first wall 18 and the second wall 19 of the cover member 5, and the wall surface 6 of the base member 4 including the substrate 7. The duct 31 divides the inside of the housing 2 into a ventilation space 32 inside the duct 31 and other spaces inside the housing 2. The ventilation space 32 extends in the vertical direction while being separated from other spaces inside the housing 2.

[0019] 6, the duct 31 according to this embodiment is formed in a stepped shape extending from the lower end on the left side to the upper end on the right side inside the housing 2. The lower end of the duct 31 is located near an opening 22 that faces downward in the housing 2, and communicates with the outside of the housing 2 via this opening 22. The upper end of the duct 31 is located near an opening 21 that faces upward in the housing 2, and communicates with the outside of the housing 2 via this opening 21. In other words, the lower and upper ends of the ventilation space 32 inside the duct 31 are communicated with the outside of the housing 2.

[0020] A temperature measuring element 3 is disposed inside the lower end of the duct 31 . The middle part of the duct 31 has a heat receiving part 33 that crosses over the heat generating component 11 in the left-right direction. The heat receiving part 33 is formed so as to be in contact with the heat generating component 11. Therefore, when the temperature sensor 1 is used, the heat of the heat generating component 11 is transferred to the heat receiving part 33 by thermal conduction, and the temperature of the heat receiving part 33 rises. When the temperature of the heat receiving part 33 rises, an upward air current is generated in the ventilation space 32. In other words, the heat generating component 11 is disposed at a position where an upward air current is generated in the ventilation space 32 by the heat of this heat generating component 11.

[0021] When an ascending air current occurs in the ventilation space 32, air is drawn into the lower end of the ventilation space 32 by the so-called chimney effect, and air is discharged from the upper end of the ventilation space 32. The air drawn into the lower end of the ventilation space 32 is air outside the housing 2 that has flowed into the housing 2 through the opening 22 at the lower end of the housing 2. The temperature measuring element 3 is disposed so as to detect the temperature of the air drawn into the lower end of the ventilation space 32 due to the occurrence of an ascending air current.

[0022] In the temperature sensor 1 configured in this manner, the temperature of the air outside the housing that is sucked into the lower end of the ventilation space 32 is measured by the temperature measuring element 3. In this embodiment, no fan is used to generate an ascending air current in the ventilation space 32, but an existing heat-generating component 11 is used, so that manufacturing costs can be kept low. In addition, since there is no configuration in which the thermal distance between the temperature measuring element 3 and the heat-generating component 11 is increased to reduce heat transfer to the temperature measuring element 3, the temperature sensor 1 can be made smaller. Therefore, according to this embodiment, a small temperature sensor capable of measuring the true temperature outside the housing 2 without being affected by the heat of the heat-generating components 11 inside the housing 2 or the heat of the walls that the housing 2 contacts can be provided at a low price.

[0023] The ventilation space 32 in this embodiment extends from the lower end to the upper end of the housing 2. This allows the vertical length of the ventilation space 32 to be maximized, which generates many upward air currents and allows more indoor air to be taken in.

[0024] The ventilation space 32 in this embodiment is formed by a duct 31 provided inside the housing 2. The duct 31 has a heat receiving portion 33 that crosses over the heat generating component 11 so that heat is transferred from the heat generating component 11. Therefore, the first wall 18 or the second wall 19 is located between the temperature measuring element 3 arranged inside the duct 31 and the heat generating component 11, so that the effects of heat conduction and radiation from the heat generating component 11 can be reduced, making it possible to perform temperature measurement with even higher accuracy.

[0025] The temperature measuring element 3 and the heat generating component 11 according to this embodiment are mounted on a substrate 7. The housing 2 has a base member 4 that supports the substrate 7 in a vertically extending position, and a cover member 5 that covers the base member 4 including the substrate 7. A pair of walls (a first wall 18 and a second wall 19) are provided on the inner surface (the rear surface 17a of the front plate 17) of the cover member 5, which protrudes toward the base member 4 and extends in the vertical direction along the wall surface 6 of the base member 4 including the substrate 7. The duct 31 is formed by the pair of walls (the first wall 18 and the second wall 19), a portion 26 between the pair of walls of the cover member 5, and the wall surface 6 of the base member 4 including the substrate 7. Therefore, the duct 31 is formed by assembling the cover member 5 to the base member 4, so there is no increase in the number of assembly steps despite the presence of the duct 31. Therefore, the duct 31 can be provided while keeping the increase in cost to a minimum.

[0026] (Second embodiment) The heat generating components can be arranged as shown in Fig. 9. In Fig. 9, members that are the same as or equivalent to those described with reference to Figs. 1 to 8 are given the same reference numerals and detailed description thereof will be omitted as appropriate. The heat generating component 11 shown in Fig. 9 is disposed in a duct 31. Therefore, the air in the duct 31 can be heated by the entire heat generating component 11, and therefore more upward air currents are generated in the duct 31 than in the case of the first embodiment. Therefore, more indoor air passes near the temperature measuring element 3, and the indoor temperature can be measured with even greater accuracy.

[0027] In each of the above-described embodiments, an example in which the duct 31 (ventilation space 32) is formed in a stepped shape has been shown. However, the shape of the duct 31 is not limited to a stepped shape and can be changed as appropriate. The shape of the duct 31 may be, for example, a shape that extends linearly in the vertical direction or a shape that extends obliquely in the vertical direction.

[0028] Although the above-mentioned embodiments have been described with respect to a temperature sensor that is attached to a wall inside a room, the present invention is not limited to such a case. In other words, the present invention can be applied to any temperature sensor that is affected by the heat inside the housing or the heat of a member that comes into contact with the housing. [Explanation of symbols]

[0029] 1...temperature sensor, 2...housing, 3...temperature measuring element, 4...base member, 5...cover member, 6...wall surface, 7...circuit board, 11...heat generating component, 18...first wall, 19...second wall, 31...duct, 32...ventilation space, 33...heat receiving portion.

Claims

1. a housing for accommodating a temperature measuring element and a heat generating component; a ventilation space provided inside the housing and extending in a vertical direction while being partitioned from other spaces inside the housing; The lower end and the upper end of the ventilation space are communicated with the outside of the housing, the heat generating component is disposed at a position where an ascending air current is generated in the ventilation space by the heat of the heat generating component, the temperature measuring element is disposed so as to detect the temperature of air drawn into the lower end of the ventilation space by the rising air current; the ventilation space is formed by a duct provided inside the housing, the duct has a heat receiving portion that crosses over the heat generating component so that heat is transferred from the heat generating component; The temperature measuring element and the heat generating component are mounted on a substrate; The housing includes a base member that supports the board in a vertically extending position; a cover member that covers the base member including the substrate, a pair of walls are provided on an inner surface of the cover member, the pair of walls protruding toward the base member and extending in a vertical direction along a wall surface of the base member including the substrate; A temperature sensor, characterized in that the duct is formed by the pair of walls, a portion of the cover member between the pair of walls, and a wall surface of the base member including the substrate.

2. A housing for accommodating a temperature measuring element and a heat generating component; a ventilation space provided inside the housing and extending in a vertical direction while being partitioned from other spaces inside the housing; The lower end and the upper end of the ventilation space are communicated with the outside of the housing, the heat generating component is disposed at a position where an ascending air current is generated in the ventilation space by the heat of the heat generating component, the temperature measuring element is disposed so as to detect the temperature of air drawn into the lower end of the ventilation space by the rising air current; the ventilation space is formed by a duct provided inside the housing, The heat generating component is disposed in the duct, The temperature measuring element and the heat generating component are mounted on a substrate; The housing includes a base member that supports the board in a vertically extending position; a cover member that covers the base member including the substrate, a pair of walls are provided on an inner surface of the cover member, the pair of walls protruding toward the base member and extending in a vertical direction along a wall surface of the base member including the substrate; A temperature sensor, characterized in that the duct is formed by the pair of walls, a portion of the cover member between the pair of walls, and a wall surface of the base member including the substrate.

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