JP6612134B2 - Enclosure with illuminant and level detection apparatus having the same - Google Patents

Description

  The present invention relates to a housing with a light emitter in which the light emitter is housed inside the housing, and the housing is configured such that light emitted from the light emitter can be visually recognized from the outside. The present invention relates to a level detection apparatus that includes a casing with a light emitter and further includes a level detection unit that detects a level of liquid or powder (for example, a storage level as typified by a liquid level).

  2. Description of the Related Art Conventionally, various devices employ a configuration in which various types of information are notified to a user using an LED (Light Emitting Diode), an LCD (Liquid Crystal Display), or the like. In order to realize the configuration, an LED or LCD as a notification unit is provided in the casing itself as an outer shell member, or a projection window is provided in the casing and the notification unit is provided inside the casing. It is necessary to adopt any structure of housing an LED or LCD.

  For example, Japanese Unexamined Patent Application Publication No. 2014-199225 (Patent Document 1) discloses a level detection device in which an LED is provided on a housing itself. In the level detection device disclosed in Patent Document 1, an LED lamp for informing the detection state based on the presence or absence of lighting is installed at a position on the upper surface of the main body case.

JP 2014-199225 A

  Here, a case is formed by a container-like case body and a lid-like cover body formed so as to be screwable, and a light projection window is provided in the cover body, and a light-emitting body is further provided inside the housing. In the case where the LED or the backlight of the LCD as a light emitter is accommodated, the light projecting window faces the light emitter in the attached state in which the cover body is screwed to the case body. It is necessary to be positioned and arranged appropriately.

  For example, when an LED is used as the light emitter and the LED and the light projection window are arranged at an eccentric position deviated from the position on the central axis of the cover body screwed to the case body, the LED rotates at the time of screwing. It is necessary to accurately position the cover body in the rotational direction, and if the positioning is insufficient, the light projection window is disposed at a position shifted from the LED, and the LED It becomes difficult to visually recognize the presence or absence of lighting.

  In addition, when an LCD is used as the notification unit, the display unit of the LCD is generally rectangular in plan view. Therefore, when the light projection window is also configured to have a rectangular shape in plan view, the cover body rotates upon screwing. It is necessary to accurately position the position of the light in the rotation direction. If the positioning is insufficient, a light projection window is disposed at a position deviated from the backlight of the LCD as the light emitter, or the backlight The light projection window is disposed in a tilted state, and it becomes difficult to visually recognize the display state of the LCD from the outside.

  Such a problem can be solved by providing some mechanism for positioning the case body and the cover body. However, the mechanism tends to be complicated in many cases, and the manufacturing cost is reduced. A separate problem has occurred.

  Accordingly, the present invention has been made in view of the above-described problems, and a housing with a light emitter having a simple configuration capable of appropriately positioning and installing a light projection window with respect to a light emitter, and the same. It is an object of the present invention to provide a level detection apparatus provided.

  A housing with a light emitter according to the present invention includes a case body provided with an opening, a cover body attached to the case body so as to close the opening, and a light emitter assembled on the case body side. It has. The light emitter is accommodated in an internal space defined by the case body and the cover body when the cover body is attached to the case body, and the cover body emits light emitted from the light emitter. Has a light projection window for projecting light to the outside. One of the case body and the cover body includes a male screw portion, and the other of the case body and the cover body includes a female screw portion into which the male screw portion can be screwed. The terminal end of one of the male screw portion and the female screw portion has a first abutting surface intersecting the extending direction of the screw groove, and the other screw of the male screw portion and the female screw portion. The starting end of the crest has a second abutting surface for abutting the first abutting surface that intersects the direction in which the thread extends. In the housing with a light emitter according to the present invention, the male threaded portion is screwed into the female threaded portion, and the second abutting surface comes into contact with the first abutting surface, so that the light projecting window is in the mounted state. Is disposed at a position facing the light emitter.

  In the case with the light emitter according to the present invention, the light emitter and the light projection window may be provided at positions eccentric from the axis of the male screw portion and the female screw portion.

  The housing with a light emitter according to the present invention may further include a packing interposed between the case body and the cover body. In that case, in the mounting state, the packing is sandwiched between the case body and the cover body in the axial direction of the male screw portion and the female screw portion and compressed, so that the restoring force causes the male screw portion and the It is preferable that the cover body is locked to the case body by pressure contact between the male screw portion and the female screw portion when the female screw portion is in pressure contact with the axial direction.

  In the case with the light emitter according to the present invention, at least one of the male screw portion and the female screw portion has a width in the vicinity of the end of the screw groove except for the vicinity of the end of the screw groove. You may have the 1st biting part comprised smaller than the width | variety. In that case, in the mounting state, the first biting part bites against the vicinity of the start end of the screw thread that is screwed into the screw groove provided with the first biting part, thereby the cover body. However, it is preferable that the case body is locked by biting of the first biting portion.

  In the case with the light emitter according to the present invention, at least one of the male screw portion and the female screw portion has a width in the vicinity of the end of the screw thread except for the vicinity of the end of the screw thread. You may have the 2nd biting part comprised larger than the width | variety. In that case, in the attached state, the second biting portion bites against the vicinity of the start end of the thread groove into which the screw thread provided with the second biting portion is screwed, and thereby the cover body. However, it is preferable that the case body is locked by biting of the second biting portion.

  In the case with a light emitter according to the present invention, it is preferable that the first butting surface and the second butting surface are both trapezoidal or rectangular.

  In the case with the light emitter according to the present invention, it is preferable that a mark that is combined in the attached state is further provided on the outer surface of the case body and the outer surface of the cover body.

  The level detection apparatus based on this invention is equipped with the housing | casing with a light emitter based on the said invention, and a level detection part.

  ADVANTAGE OF THE INVENTION According to this invention, the housing | casing with a light-emitting body of a simple structure which can position and arrange a light projection window appropriately with respect to a light-emitting body, and a level detection apparatus provided with the same can be provided.

It is a schematic front view of the level detection apparatus in Embodiment 1 of this invention. It is a top view of the level detection apparatus shown in FIG. It is a schematic sectional drawing of the principal part of the level detection apparatus shown in FIG. It is an exploded view which shows the assembly | attachment structure of the level detection apparatus shown in FIG. It is a schematic diagram which shows the shape of the external thread part provided in the case body of the level detection apparatus shown in FIG. It is a schematic diagram which shows the shape of the internal thread part provided in the cover body of the level detection apparatus shown in FIG. It is a schematic diagram which shows the shape of the external thread part provided in the case body of the level detection apparatus which concerns on a 1st modification. It is a schematic diagram which shows the shape of the internal thread part provided in the cover body of the level detection apparatus which concerns on a 1st modification. It is a schematic sectional drawing of the principal part of the level detection apparatus in Embodiment 2 of this invention. It is an exploded view which shows the assembly structure of the level detection apparatus shown in FIG. It is a schematic diagram which shows the shape of the external thread part provided in the case body of the level detection apparatus shown in FIG. 9, and the shape of the internal thread part provided in the cover body. It is a schematic diagram which shows the shape of the external thread part provided in the case body of the level detection apparatus which concerns on a 2nd modification, and the shape of the internal thread part provided in the cover body.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the embodiment described below, a case where the present invention is applied to a level detection device including a level detection unit that detects a liquid level of a liquid will be described as an example. In the following embodiments, the same or common parts are denoted by the same reference numerals in the drawings, and description thereof will not be repeated.

(Embodiment 1)
1 is a schematic front view of a level detection apparatus according to Embodiment 1 of the present invention, and FIG. 2 is a top view of the level detection apparatus shown in FIG. 3 is a schematic cross-sectional view of the main part of the level detection device shown in FIG. 1, taken along line III-III shown in FIG. 2, and FIG. 4 shows the assembly structure of the level detection device shown in FIG. It is an exploded view. FIG. 5 is a schematic view showing the shape of the male screw portion provided in the case body of the level detection device shown in FIG. 1, and FIG. 5 (A) is a plan view of the male screw portion seen from the VA direction shown in FIG. FIG. 5 and FIG. 5B are perspective views of the male screw portion viewed from the direction of the arrow VB shown in FIG. 6 is a schematic diagram showing the shape of the female screw portion provided in the cover body of the level detection device shown in FIG. 1, and FIG. 6 (A) is a plan view of the female screw portion seen from the VIA direction shown in FIG. FIG. 6B is a perspective view of the female screw portion viewed from the direction of the arrow VIB shown in FIG.

  As shown in FIGS. 1 and 2, the level detection device 1 </ b> A according to the present embodiment has a substantially cylindrical outer shape as a whole, and includes a housing formed of a container-like case body 10 and a lid-like cover body 20. And a level detection unit 30 provided so as to protrude from the housing. The casing made up of the case body 10 and the cover body 20 is located in the upper part of the level detection apparatus 1A, and the level detection unit 30 is located in the lower part of the level detection apparatus 1A. An installation mechanism 60 for installing the level detection device 1 </ b> A on a wall surface such as a tank is provided between the case body 10 and the cover body 20 and the level detection unit 30.

  The cover body 20 is attached to the case body 10 by screwing, and various electronic components such as a microcomputer and a light-emitting body 41 are provided inside the casing constituted by the case body 10 and the cover body 20. Internal components including such as are housed. The case body 10 and the cover body 20 are preferably made of a resin member, but may be made of a metal member.

  The level detection unit 30 is a part for detecting the liquid level, and is configured by a detection mechanism corresponding to a conventionally known level detection method. Here, conventionally known level detection methods include, for example, a level detection method using ultrasonic waves, a level detection method using a tuning fork, a level detection method using a capacitive sensor, and a level detection using a rotor blade. And a detection method using a float and the like.

  The output from the level detection unit 30 is input to the above-described microcomputer, and a detection result is derived by performing various arithmetic processes in the microphone computer. Based on the detection result, the microcomputer controls whether or not the light emitter 41 is turned on as a notification unit, and thereby notifies the user of the detection state based on whether or not the light emitter 41 is turned on. Note that a light projection window 23 is provided at a predetermined position of the cover body 20 so that the light emitted from the light emitting body 41 can be visually recognized with certainty.

  Here, it is not always necessary to notify the detection state depending on whether or not the light-emitting body 41 is turned on, and the detection state is notified by turning off and blinking, turning on and blinking, changing the blinking interval, changing the color of emitted light, and the like. You may comprise. Further, it is not always necessary to notify the detection state by the light emitter 41, and instead of or in addition to the notification of the detection state, the light emitter 41 is notified of the presence / absence of power supply or the operation state. May be.

  As described above, the level detection device 1 </ b> A according to the present embodiment includes a housing with a light emitter in which the light emitter 41 is accommodated inside the housing. Here, as shown in FIG. 2 and FIG. 3 and the like, in the level detection apparatus 1A in the present embodiment, the light emitter 41 and the light projection window 23 are both provided at positions eccentric from the central axis CA of the housing. It has been. Therefore, in order to ensure that the user can visually recognize whether or not the light-emitting body 41 is lit, it is necessary to accurately position the cover body 20 that rotates upon screwing in the rotational direction.

  Therefore, in the level detection apparatus 1A in the present embodiment, the case body 10 and the cover body 20 are provided with a characteristic configuration described later in order to ensure the positioning. In the following, a more detailed configuration and assembly structure of the level detection device 1A in the present embodiment will be described, and the characteristic configuration will be described in detail.

  As shown in FIGS. 1 to 3, the case body 10 includes a container portion 11 that defines a space inside the housing, and the container portion 11 has a cylindrical shape with a narrowed lower end. . A cable connecting portion 12 is provided at a predetermined position of the container portion 11. The cable connecting portion 12 is a portion to which a power supply cable (not shown) for supplying power to the various electronic components described above is connected.

  An opening 13 is provided in the upper part of the container part 11. The opening 13 is a part for exposing the space inside the container part 11 to the outside in a non-attached state (see FIG. 4) where the cover body 20 is not attached to the case body 10. In addition, a flange 14 that extends along the circumferential direction of the container 11 and protrudes toward the outside of the container 11 is provided at a predetermined position on the outer peripheral surface near the upper end where the opening 13 of the container 11 is provided. It has been.

  The case body 10 is assembled with the light emitting body 41 described above. More specifically, the light emitter 41 is housed inside the case body 10 and mounted on the circuit board 40 fixed to the case body 10, whereby the light emitter 41 is interposed via the circuit board 40. The case body 10 is assembled. Here, the light emitter 41 is arranged so as to face the opening 13 of the case body 10.

  The cover body 20 includes a top plate portion 21 for closing the opening 13 provided in the case body 10 and a cylindrical peripheral wall portion 22 erected from the periphery of the top plate portion 21. A light projecting window 23 for projecting light emitted from the light emitting body 41 to the outside is provided at a predetermined position of the top plate portion 21, and the light projecting window 23 is a translucent light that can transmit the light. The member 24 is fitted.

  As shown in FIGS. 3 and 4, a male screw portion 15 is provided on an outer peripheral surface of a portion of the container portion 11 of the case body 10 that is located on the opening 13 side (that is, the upper end side) with respect to the above-described flange portion 14. Is provided. As shown in FIG. 5, the male screw portion 15 is configured by a screw thread 16 and a screw groove 17 provided in a spiral shape, and the axis of the male screw portion 15 is arranged so as to coincide with the central axis CA of the housing. Has been. The male screw portion 15 is a so-called trapezoidal screw in which the cross section of the thread 16 perpendicular to the direction in which the thread 16 extends is a trapezoid.

  As shown in FIGS. 3 and 4, an internal thread portion 25 is provided on the inner peripheral surface of the peripheral wall portion 22 of the cover body 20. As shown in FIG. 6, the female screw portion 25 includes a screw thread 26 and a screw groove 27 provided in a spiral shape, and the axis of the female screw portion 25 is arranged so as to match the central axis CA of the housing. Has been. The female thread portion 25 is a so-called trapezoidal screw in which the cross section of the thread 26 perpendicular to the direction in which the thread 26 extends is a trapezoid.

  The male screw portion 15 provided in the case body 10 is configured to be screwed into the female screw portion 25 provided in the cover body 20, and the male screw portion 15 is screwed into the female screw portion 25 in the attached state shown in FIG. As a result, the cover body 20 is attached to the case body 10.

  Here, in the level detection device 1A according to the present embodiment, the external thread of the thread 16 of the external thread 15 is configured to be smaller than the thread groove 27 of the internal thread 25 into which the thread 16 is screwed. The external thread of the female thread part 25 is configured to be smaller than the thread groove 17 of the male thread part 15 into which the thread 26 is screwed. Therefore, the male screw portion 15 provided in the case body 10 and the female screw portion 25 provided in the cover body 20 are directly screwed together (that is, the thread provided on one of the male screw portion 15 and the female screw portion 25 and The screw groove provided on the other side does not bite only by screwing the male screw part 15 into the female screw part 25), and the male screw part 15 and the female screw part 25 are brought into pressure contact by the restoring force of the packing 50 described later, The cover body 20 is configured to be locked to the case body 10, and details thereof will be described later.

  As shown in FIGS. 3 and 4, a packing 50 made of an O-ring is interposed between the case body 10 and the cover body 20. More specifically, the packing 50 is disposed on the outer peripheral surface of the container part 11 of the case body 10 and on the upper surface of the flange part 14, and in the attached state shown in FIG. 14 and the peripheral wall portion 22 of the cover body 20, so that it is compressed in the direction of the central axis CA of the housing.

  The packing 50 is used to liquid-tightly seal the space inside the housing formed of the case body 10 and the cover body 20 and to lock the cover body 20 to the case body 10 as described above. It is. The male screw portion 15 and the female screw portion 25 described above are provided at a position closer to the opening 13 than the packing 50.

  As shown in FIG. 4, when attaching the cover body 20 to the case body 10, the packing 50 is assembled to the case body 10 in advance, and the case body 10 is closed so as to close the opening 13 of the case body 10 in this state. This is done by screwing the male screw portion 15 into the female screw portion 25 of the cover body 20. Here, the male screw portion 15 provided in the case body 10 and the female screw portion 25 provided in the cover body 20 are both configured by right-hand threads, and in FIG. Screwed by rotating clockwise around.

  Along with the screwing, the peripheral wall portion 22 of the cover body 20 gradually moves toward the flange portion 14 side of the case body 10, whereby the packing 50 moves between the flange portion 14 of the case body 10 and the cover body 20. It will be sandwiched between the peripheral wall portion 22. By further screwing, the packing 50 is compressed in the direction of the central axis CA of the housing.

  Here, as described above, in the level detection apparatus 1A according to the present embodiment, as shown in FIG. 2, the light emitter 41 and the light projection window 23 are both in a position eccentric from the central axis CA of the housing. Is provided. Therefore, in the level detection device 1A according to the present embodiment, the positioning unit, which is a characteristic configuration for accurately positioning the rotating cover body 20 in the rotational direction at the time of the above-described screwing, includes the male screw described above. It is provided in the part 15 and the female thread part 25.

  More specifically, the positioning portion described above includes a first abutting surface 17b1 (see FIG. 5) provided on the male screw portion 15 and a second abutting surface 26a1 (see FIG. 6) provided on the female screw portion 25. It is configured. Here, the positioning portion is a portion that does not appear in the top view of the level detection device 1A shown in FIG. 2, but for the sake of easy understanding, the positioning portion is present in a plan view. The portion is represented by an area AP in FIG. More specifically, referring to FIG. 2, when the center axis CA of the housing is the center, the positioning portion described above is 225 ° clockwise from the position where the light emitter 41 and the projection window 23 are provided. It is provided in the position.

  Referring to FIG. 5, the first abutting surface 17b1 described above is provided at the terminal end 17b of the thread groove 17 of the male screw portion 15 located on the lower end side of the case body 10, and more specifically, the screw. The end face of the thread groove 17 is provided so as to intersect the direction in which the groove 17 extends. Here, since the male screw portion 15 is a trapezoidal screw as described above, the shape of the first abutting surface 17b1 is also configured as a trapezoid.

  With reference to FIG. 6, the second abutting surface 26 a 1 described above is provided at the start end 26 a of the thread 26 of the female screw portion 25 located on the lower end side of the cover body 20, and more specifically, the screw It is comprised by the starting end surface of the screw thread 26 provided so that the thread | cross 26 may extend in the extending direction. Here, as described above, since the female screw portion 25 is a trapezoidal screw, the shape of the second abutting surface 26a1 is also configured as a trapezoid.

  In other words, in the present embodiment, the terminal end of the male screw portion 15 provided in the case body 10 is configured by a complete screw portion that does not include an incomplete screw portion, and the female screw provided in the cover body 20 The starting end of the portion 25 is constituted by a complete screw portion that does not include an incomplete screw portion.

  With this configuration, when the male screw portion 15 is screwed into the female screw portion 25, the start end 26a of the thread 26 of the female screw portion 25 is moved from the start end side of the screw groove 17 of the male screw portion 15 toward the end 17b side. The second abutting surface 26a1 provided at the start end 26a of the screw thread 26 is finally brought into contact with the first abutting surface 17b1 provided at the terminal end 17b of the screw groove 17 by proceeding in the thread groove 17. This contact prevents further screwing.

  Therefore, by adopting the above configuration, the light projecting window 23 is connected to the light emitting body 41 in the mounting state in which the male screw portion 15 is screwed into the female screw portion 25 and the second abutting surface 26a1 is in contact with the first abutting surface 17b1. It is surely positioned and arranged at the facing position. Therefore, by using the level detection device 1A in the present embodiment, the light projection window 23 is not disposed at a position shifted from the light emitter 41, and it is possible to visually recognize whether the light emitter 41 is turned on from the outside. It becomes possible.

  On the other hand, the shape of the male screw portion 15 and the shape of the female screw portion 25 described above can be easily realized by injection molding, cutting, or the like when the case body 10 and the cover body 20 are made of resin members. In the case where the case body 10 and the cover body 20 are made of a metal member, it can be easily realized by cutting or the like, and the positioning mechanism is not complicated. Therefore, by using the level detection apparatus 1A in the present embodiment, positioning can be performed with a simple configuration, so that the manufacturing cost is hardly increased.

  Further, in the level detection device 1A according to the present embodiment, as described above, the male screw portion 15 provided in the case body 10 and the female screw portion 25 provided in the cover body 20 are directly screwed together. Absent. Therefore, a separate locking mechanism for the cover body 20 with respect to the case body 10 is required, but as described above, this is realized by the restoring force of the packing 50 in the level detection device 1A in the present embodiment.

  More specifically, in the level detection device 1A according to the present embodiment, as described above, the packing 50 is interposed between the case body 10 and the cover body 20, and the male screw portion 15 is connected to the female screw portion 25. At the time of screwing, the packing 50 is sandwiched and compressed by the flange portion 14 of the case body 10 and the peripheral wall portion 22 of the cover body 20. Therefore, based on the restoring force of the compressed packing 50, the cover body 20 is elastically biased in a direction away from the case body 10, and the male screw portion 15 and the female screw portion 25 are accordingly connected to the housing. Will be pressed in the direction of the central axis CA. The cover body 20 is locked to the case body 10 by the pressure contact between the male screw portion 15 and the female screw portion 25.

  Therefore, by adopting this configuration, the cover body 20 can be firmly attached to the case body 10 with a very simple structure in which the packing 50 is interposed between the case body 10 and the cover body 20. In this sense, the manufacturing cost can be reduced.

  1 and 2, in level detection device 1 </ b> A in the present embodiment, in addition to the positioning by the positioning unit described above, alignment mark AM that is to be combined in the attached state is provided on case body 10. It is further provided at a predetermined position on the outer surface and a predetermined position on the outer surface of the cover body 20. More specifically, referring to FIG. 2, when the center axis CA of the housing is the center, the mark AM is 90 ° clockwise from the position where the light emitter 41 and the light projection window 23 are provided. It is provided in the position.

  In this case, when the male screw portion 15 is screwed into the female screw portion 25, it can be visually confirmed whether or not the positioning is completed, and the positioning operation can be performed more easily and reliably. .

  In addition, in the present embodiment, as described above, the case where both the first abutting surface 17b1 and the second abutting surface 26a1 as the positioning portion are configured in a trapezoidal shape has been described. In such a configuration, the area where the first butting surfaces 17b1 and 26a1 come into contact with each other can be increased. Therefore, by adopting this configuration, when the male screw portion 15 is screwed into the female screw portion 25, not only can the positioning be performed more reliably and accurately, but also the male screw portion provided with the first abutting surface 17b1. The strength of the terminal end 17b of the fifteen screw grooves 17 and the strength of the starting end 26a of the thread 26 of the female thread portion 25 provided with the second abutting surface 26a1 can be ensured. It is possible to prevent the positioning portion including the first butting surface 17b1 and the second butting surface 26a1 from being damaged by repeated attachment and detachment.

  The shapes of the first butting surfaces 17b1 and 26a1 may be triangular or rectangular. However, from the viewpoint of increasing the area where the first abutting surface 17b1 and the second abutting surface 26a1 abut, it is more preferable that these shapes be the trapezoidal shape or the rectangular shape described above.

(First modification)
FIG. 7 is a schematic diagram showing the shape of the male screw portion provided in the case body of the level detection device according to the first modification based on the first embodiment described above, and FIG. FIG. 7B is a plan view of the male screw portion viewed from the direction of the arrow VIIB shown in FIG. FIG. 8 is a schematic diagram showing the shape of the female thread portion provided in the cover body of the level detection device according to the first modification based on the first embodiment described above, and FIG. FIG. 8B is a perspective view of the female screw portion viewed from the direction of arrow VIIIB shown in FIG.

  In the first embodiment described above, the first butting surface 17b1 as the positioning portion is provided at the terminal end 17b of the screw groove 17 of the male screw portion 15, and the second butting surface 26a1 as the positioning portion is the female screw portion 25. However, the formation positions of the first butting surfaces and the second butting surfaces constituting these positioning portions are not limited to this, and, for example, as in the first modification example It is good.

  With reference to FIG. 7, in the level detection device 1 </ b> A <b> 1 according to the first modification, the second abutting surface 16 a <b> 1 is provided at the start end 16 a of the thread 16 of the male screw portion 15 located on the upper end side of the case body 10. More specifically, it is constituted by the starting end face of the thread 16 provided so as to intersect with the direction in which the thread 16 extends.

  Referring to FIG. 8, in the level detection device 1 </ b> A <b> 1 according to the first modification, the first abutting surface 27 b <b> 1 is located at the terminal end 27 b of the screw groove 27 of the female screw portion 25 located on the upper end side of the cover body 20. More specifically, it is configured by the end face of the screw groove 27 provided so as to intersect the direction in which the screw groove 27 extends.

  In other words, in the first modified example, the start end of the male screw portion 15 provided in the case body 10 is configured by a complete screw portion that does not include an incomplete screw portion, and is provided in the cover body 20. The terminal end of the female screw portion 25 is constituted by a complete screw portion that does not include an incomplete screw portion.

  With this configuration, when the male screw portion 15 is screwed into the female screw portion 25, the start end 16a of the thread 16 of the male screw portion 15 is moved from the start end side of the screw groove 27 of the female screw portion 25 toward the end 27b side. The second abutting surface 16a1 provided at the start end 16a of the screw thread 16 finally abuts on the first abutting surface 27b1 provided at the terminal end 27b of the screw groove 27 by proceeding in the screw groove 27, This contact prevents further screwing.

  Therefore, even when the configuration is adopted, the same effect as that described in the first embodiment can be obtained, and the light projection window 23 is appropriately positioned with respect to the light emitter 41 and installed. Therefore, the level detection device 1A1 can be configured with a simple configuration.

(Embodiment 2)
FIG. 9 is a schematic cross-sectional view of the main part of the level detection device according to Embodiment 2 of the present invention, and FIG. 10 is an exploded view showing the assembly structure of the level detection device shown in FIG. FIG. 11 is a schematic diagram showing the shape of the male screw portion provided in the case body of the level detection device shown in FIG. 9 and the shape of the female screw portion provided in the cover body, and FIG. FIG. 11B is a plan view showing the shape of the female screw portion.

  The level detection device 1B in the present embodiment is different only in the configuration of the locking mechanism of the cover body 20 with respect to the case body 10 when compared with the level detection device 1A in the first embodiment described above. Specifically, as shown in FIGS. 9 and 10, in the level detection device 1 </ b> B according to the present embodiment, an annular recess 18 is provided at a predetermined position on the outer peripheral surface of the container portion 11 of the case body 10. The male screw portion 15 of the case body 10 is screwed into the female screw portion 25 of the cover body 20 so as to close the opening 13 of the case body 10 in a state where the packing 50 is accommodated in the annular recess 18. It is attached to the case body 10.

  In this case, as the male screw portion 15 is screwed into the female screw portion 25, the packing 50 is sandwiched between the bottom surface of the annular recess 18 of the case body 10 and the inner peripheral surface of the peripheral wall portion 22 of the cover body 20, The packing 50 is compressed in a direction orthogonal to the central axis CA direction of the housing. Therefore, since the restoring force of the packing 50 does not act in the direction of the central axis CA of the casing, a separate locking mechanism for the cover body 20 with respect to the case body 10 is necessary, but the level detection device 1B in the present embodiment. In this case, this is realized by the biting of the first biting portion 17 c provided in the male screw portion 15.

  More specifically, referring to FIG. 11A, the first biting portion 17c described above is provided in the vicinity of the terminal end 17b of the screw groove 17 of the male screw portion 15 located on the lower end side of the case body 10. More specifically, the width Wa1 in the vicinity of the end 17b of the screw groove 17 is configured to be smaller than the width Wa2 of the portion excluding the vicinity of the end 17b of the screw groove 17, so that the first biting portion 17c is formed. Is formed. The width Wa1 of the screw groove 17 corresponding to the first biting portion 17c is configured to gradually decrease as the end of the screw groove 17 is approached, whereby the first biting portion 17c It is comprised by 17 taper parts.

  On the other hand, referring to FIG. 11 (B), the thread 26 of the female screw portion 25 provided in the cover body 20 is uniformly larger in width than at least the narrowest portion of the first biting portion 17c. The first biting portion 17c also has an outer shape, and the first biting portion 17c in the vicinity of the start end 26a of the screw thread 26, which is a portion into which the first biting portion 17c is screwed in the attached state. It has a larger width than the narrowest part.

  Therefore, when the male screw portion 15 is screwed into the female screw portion 25, the first biting portion 17c is inserted into the screw groove 17 provided with the first biting portion 17c in the vicinity of the first end of the screw thread 26. The bite portion 26d is bitten. The cover body 20 is locked to the case body 10 by the biting of the first biting portion 17c.

  With this configuration, the cover body 20 is firmly attached to the case body 10 with a very simple configuration in which the first biting portion 17c is provided in the vicinity of the terminal end 17b of the thread groove 17 of the male screw portion 15. In this sense, the manufacturing cost can be reduced.

  Therefore, even when the configuration is adopted, the same effect as that described in the first embodiment can be obtained, and the light projection window 23 is appropriately positioned with respect to the light emitter 41 and installed. Therefore, the level detection device 1B can be configured with a simple configuration.

(Second modification)
FIG. 12 is a schematic diagram showing the shape of the male screw portion provided in the case body of the level detection device according to the second modification based on the second embodiment described above and the shape of the female screw portion provided in the cover body. 12A is a plan view showing the shape of the male screw portion, and FIG. 12B is a plan view showing the shape of the female screw portion.

  In the second embodiment described above, the first biting portion 17c as the locking mechanism is provided in the vicinity of the terminal end 17b of the screw groove 17 of the male screw portion 15, but the locking mechanism including the biting portion is not provided. The formation position is not limited to this, and may be as in the second modification, for example.

  Referring to FIG. 12B, in the level detection device 1B1 according to the second modification, the second biting portion 26c is located at the upper end side of the cover body 20, and is the end of the thread 26 of the female screw portion 25. More specifically, since the width Wb1 in the vicinity of the end of the screw thread 26 is larger than the width Wb2 of the portion excluding the vicinity of the end of the screw thread 26, the second bite is provided. A portion 26c is formed. The width Wb1 of the thread 26 of the portion corresponding to the second biting portion 26c is configured to gradually increase toward the end of the screw 26, whereby the second biting portion 26c It is comprised by 26 taper parts.

  On the other hand, referring to FIG. 12A, the screw groove 17 of the male screw portion 15 provided in the case body 10 is uniformly smaller in width than at least the widest portion of the second biting portion 26c. Even in the second biting portion 17d in the vicinity of the start end of the thread groove 17, which is the portion into which the second biting portion 26c is screwed in the attached state, the most of the second biting portion 26c. It has a smaller width than the larger portion.

  Therefore, when the male screw portion 15 is screwed into the female screw portion 25, the second biting portion 26 c is inserted into the second covered portion near the starting end of the screw groove 17 into which the screw thread 26 provided with the second biting portion 26 c is screwed. The biting portion 17d is bitten. The cover body 20 is locked to the case body 10 by the biting of the second biting portion 26c.

  With this configuration, the cover body 20 can be firmly attached to the case body 10 with a very simple configuration in which the second biting portion 26c is provided in the vicinity of the terminal end of the thread 26 of the female screw portion 25. In this sense, the manufacturing cost can be reduced.

  Therefore, even when the configuration is adopted, the same effect as that described in the first embodiment can be obtained, and the light projection window 23 is appropriately positioned with respect to the light emitter 41 and installed. Therefore, the level detection device 1B1 can be configured with a simple configuration.

  In the above-described first and second embodiments of the present invention and the modifications thereof, the description has been given by exemplifying the case where the LED is used as the light emitter. However, when the LCD is used as the notification unit, the LCD back Light can also be used as a light emitter. In that case, by applying the present invention, the light projection window is arranged at a position deviated from the backlight of the LCD as the light emitter, or the light projection window is arranged in a tilted state with respect to the backlight. Thus, the display state of the LCD can be reliably recognized from the outside. When an LCD is used as the notification unit, even when an LCD and a light projection window are provided at a position on the central axis of the housing, the projector is tilted with respect to the backlight by applying the present invention. It is possible to reliably prevent the optical window from being arranged.

  In the above-described first and second embodiments of the present invention and the modifications thereof, a case where a single light emitter and a single light projection window are provided corresponding thereto will be described as an example. However, the present invention is naturally applicable even when a plurality of light emitters and a plurality of light projection windows are provided corresponding thereto.

  Moreover, in Embodiment 1 and 2 of this invention mentioned above, and its modification example, although the case where the male screw part was provided in the case body and the female screw part was provided in the cover body was illustrated and demonstrated, Of course, it is possible to provide a male screw part and a female screw part in the case body.

  In the above-described first and second embodiments of the present invention and the modifications thereof, a packing is interposed between the case body and the cover body in order to liquid-tightly seal the space inside the housing from the outside. However, it is not always necessary to make such a configuration, and the present invention can also be applied to a case with a light emitter that does not require liquid-tightness. . In that case, for example, the installation of the packing may be omitted while adopting the locking mechanism as in the second embodiment of the present invention described above, or the above described only for the purpose of locking the cover body to the case body. You may employ | adopt the structure like Embodiment 1 of this invention.

  Further, the characteristic configurations exemplified in the above-described first and second embodiments of the present invention and modifications thereof can naturally be combined with each other without departing from the spirit of the present invention. For example, while adopting the configuration as in the first embodiment of the present invention described above, it is possible to further include a locking mechanism as in the second embodiment of the present invention described above.

  Furthermore, in the above-described first and second embodiments of the present invention and the modifications thereof, the case where the present invention is applied to the level detection device has been described by way of example, but the device having a casing with a light emitter As a matter of course, the present invention can be applied to any apparatus.

  As described above, the above-described embodiment and its modifications disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  1A, 1A1, 1B, 1B1 Level detection device, 10 case body, 11 container portion, 12 cable connection portion, 13 opening portion, 14 flange portion, 15 male screw portion, 16 thread, 16a start end, 16a1 second abutting surface, 17 Thread groove, 17b end, 17b1 first abutting surface, 17c first biting part, 17d second biting part, 18 annular recess, 20 cover body, 21 top plate part, 22 peripheral wall part, 23 light projection window, 24 Translucent member, 25 female thread portion, 26 thread, 26a start end, 26a1 second abutting surface, 26c second biting portion, 26d first biting portion, 27 thread groove, 27b terminal, 27b1 first abutting surface, 30 Level detection unit, 40 circuit board, 41 illuminant, 50 packing, 60 installation mechanism.

Claims (8)

A case body provided with an opening,
A cover body attached to the case body so as to close the opening,
A light emitter assembled on the case body side,
The light emitter is accommodated in an internal space defined by the case body and the cover body in an attached state in which the cover body is attached to the case body,
The cover body has a light projection window for projecting light emitted from the light emitter to the outside,
One of the case body and the cover body includes a male screw part,
The other of the case body and the cover body includes a female screw portion into which the male screw portion can be screwed,
The terminal end of one of the male screw part and the female screw part has a first abutting surface that intersects with the direction in which the screw groove extends,
A leading end of the other thread of the male threaded part and the female threaded part has a second butting surface for intersecting the first butting surface intersecting the direction in which the threading extends;
When the male threaded portion is screwed into the female threaded portion and the second abutting surface comes into contact with the first abutting surface, the light projecting window is disposed at a position facing the light emitter in the attached state. Enclosure with light emitter.   The housing with a light emitter according to claim 1, wherein both the light emitter and the light projection window are provided at positions deviated from axes of the male screw portion and the female screw portion. Further comprising a packing interposed between the case body and the cover body,
In the attached state, the packing is sandwiched between the case body and the cover body in the axial direction of the male screw part and the female screw part and compressed so that the male screw part and the female screw part are The housing with a light emitter according to claim 1 or 2, wherein the cover body is locked to the case body by pressure contact between the male screw portion and the female screw portion by press-contacting in the axial direction. At least one of the male screw portion and the female screw portion has a first biting portion in which the width in the vicinity of the end of the screw groove is smaller than the width of the portion excluding the vicinity of the end of the screw groove. And
In the mounted state, the first biting portion bites against the vicinity of the start end of the screw thread that is screwed into the screw groove provided with the first biting portion, so that the cover body has the first biting portion. The housing with a light emitter according to any one of claims 1 to 3, which is locked to the case body by biting of a biting portion. At least one of the male screw portion and the female screw portion has a second biting portion in which the width in the vicinity of the end of the screw thread is larger than the width of the portion excluding the vicinity of the end of the screw thread. And
In the attached state, the second bite portion bites against the vicinity of the start end of the thread groove into which the screw thread provided with the second bite portion is screwed, so that the cover body has the second bite. The case with a light emitter according to any one of claims 1 to 4, which is locked to the case body by biting of a biting portion.   The housing with a light emitter according to any one of claims 1 to 5, wherein each of the first butting surface and the second butting surface has a trapezoidal shape or a rectangular shape.   The case with a light emitter according to any one of claims 1 to 6, wherein a mark to be combined in the attached state is further provided on an outer surface of the case body and an outer surface of the cover body. A housing with a light emitter according to any one of claims 1 to 7,
A level detection apparatus comprising a level detection unit.