JP7419160B2 - How to assemble the watt-hour meter casing and the watt-hour meter - Google Patents

Description

The present invention relates to a housing for a power meter. Furthermore, the present invention relates to a method of assembling a power meter.

In recent years, the globalization of production systems in various industrial fields has progressed, and electricity meters are also produced in overseas factories. However, some of the built-in parts of electricity meters may be assembled at domestic factories. In the case of an electronic watt-hour meter, for example, the housing (in other words, the case) is molded overseas, terminal fittings and switches are assembled, and after being transported to Japan, the electronic circuit board and nameplate are attached, and the product is sealed. do.

The housing of an electronic watt-hour meter includes, for example, a lower case with an open top and a fixed electronic circuit board, and an upper case with an open bottom and fixed to the lower case so as to cover the electronic circuit board. and can be provided. A liquid crystal display board is attached to an electronic circuit board along with electronic components that calculate the amount of power used. The upper case and the lower case are removably fixed to each other. Therefore, for example, the manufacturing of the upper and lower cases and the attachment of terminal fittings etc. can be carried out at an overseas factory, and the final assembly process including attachment of electronic circuit boards etc. can be carried out at a domestic factory. In this case, it is necessary to separate the upper case and lower case, which are once fixed, before the final assembly process. However, conventionally, the upper case and the lower case have been configured to be firmly fixed at a plurality of locations in order to prevent mischief such as power theft. Separating the tightly fixed upper and lower cases and then fixing them again complicates the assembly work of the watt-hour meter. Although it is conceivable to hold the upper case and lower case separately until the final assembly process, there is a risk that the cases may be lost and/or damaged during transportation.

One of the objects of the present invention is to provide a casing for a watt-hour meter that allows easy transportation and assembly of the watt-hour meter. Another object of the present invention is to provide a method for assembling a watt-hour meter that allows easy transportation and assembly of the watt-hour meter.

means to solve problems

According to an embodiment of the present invention, there is provided a casing of a power meter consisting of an upper case with an open lower part and a lower case with an open upper part, the upper case and the lower case being detachably connected to each other. It is equipped with a plurality of fixing parts for fixing, and each of the plurality of fixing parts engages with an engaging claw provided on the inner surface of the upper case and an engaging claw provided on the outer surface of the lower case. the upper case and the lower case are fixed in the final assembly position of the watt-hour meter by the engaging pawl engaging the first engaging protrusion. Some of the fixing parts of the plurality of fixing parts further include a second engagement convex part that is provided on the outer surface of the lower case and is engageable with the engagement claw. , it is possible to provide a housing in which the second engagement protrusion is disposed at a position above the first engagement protrusion.

Further, according to an embodiment of the present invention, there is provided a method for assembling a watt-hour meter, the step of preparing an upper case with an open lower part and a lower case with an open upper part, comprising: A step in which first engaging protrusions arranged in the vertical direction and second engaging protrusions located above the first engaging protrusions are provided on the outer surface of the side case. , a step of fitting the upper case to the lower case until the engaging pawl provided on the inner surface of the upper case engages with the second engaging protrusion; and engaging with the second engaging protrusion. A process of separating the upper case from the lower case by releasing the engagement with the claw, and fitting the upper case to the lower case again until the engagement claw engages with the first engagement protrusion. An assembly method can be provided that includes the steps of: attaching the upper case and sealing the sealing screws attached to the upper case and the lower case.

1 is a diagram showing an overall outline of a power meter to which an embodiment of the present invention is applied. FIG. 2 is a diagram showing the lower case of FIG. 1 alone. FIG. 3 is a rear perspective view of the lower case. FIG. 2 is a diagram showing the upper case of FIG. 1 alone. FIG. 6 is a rear perspective view of the upper and lower cases in their final fixed positions. It is a figure explaining the final fixed position of an upper side and a lower side case. It is a figure explaining the final fixed position of an upper side and a lower side case. It is a figure explaining the fixing method of an upper side and a lower side case. It is a figure explaining the fixing method of an upper side and a lower side case. It is a figure explaining the fixing method of an upper side and a lower side case.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 10. Note that the following description is merely an example, and is not intended to limit the technical scope of the present invention to the following embodiments. Further, in the drawings, the same or corresponding components are given the same reference numerals and redundant explanations will be omitted.

As an example, the watt-hour meter to which this embodiment is applied may be an electronic watt-hour meter. FIG. 1 is a diagram showing an overall outline of an electronic watt-hour meter 100 (hereinafter referred to as watt-hour meter 100). The watt-hour meter 100 can include, as an example, a meter section 102 that can be electrically connected to the terminal block 101. The terminal block 101 is connected to a power distribution line (not shown) via a power distribution line insertion port 101a. The watt-hour meter 100 can be installed on a wall surface of a house, building, etc., with the terminal block 101 positioned below the meter section 102. In FIG. 1 and the like, an arrow D indicates the vertical direction (in other words, the vertical direction) when the electricity meter 100 is installed. In the following description, unless otherwise specified, terms indicating directions such as top, bottom, front, and rear are used with respect to the installed state of the watt-hour meter 100.

The meter section 102 has a resin housing (in other words, a case) 105 in which electronic components and the like for measuring the amount of power used are built-in. As shown in FIG. 1, in this embodiment, the housing 105 includes a lower case 106 and an upper case 108. Note that the specific shapes of the lower case 106 and the upper case 108 are not limited to the illustrated example.

The housing 105 includes a plurality of fixing parts for removably fixing the lower case 106 and the upper case 108 to each other. Each fixing portion includes an engaging pawl provided on the inner surface of the upper case 108 and at least one engaging convex portion provided on the outer surface of the lower case 106 and capable of engaging with the engaging pawl. In this embodiment, four fixing parts are provided on the back side and the side side of the housing 105. Details of each fixing part will be described later.

FIG. 2 is a diagram showing the lower case 106 shown in FIG. 1 alone. FIG. 3 is a rear perspective view of the lower case 106. As illustrated, the lower case 106 may include a board accommodating part 109 and a terminal fitting accommodating part 110. The substrate accommodating portion 109 may include a substrate installation surface portion 112 that extends substantially horizontally with respect to the vertical direction D. The terminal fitting accommodating portion 110 may extend downward from the rear of the board installation surface portion 112. As specifically shown in FIG. 3, the lower case 106 has an open top opening 114. An electronic circuit board (not shown) can be received in the cavity of the board receiving portion 109 through the upper opening 114 . The electronic circuit board may be supported on the board installation surface part 112 by the board support part 116 so that its mounting surface faces the front side of the watt-hour meter 100. A terminal fitting (not shown) may be placed in the terminal fitting accommodating portion 110. The terminal fittings are arranged so as to be electrically connected to the terminal block 101 when the terminal block 101 is fixed to the meter section 102.

As shown in FIG. 2, the lower case 106 has a screw hole 118. A sealing screw (not shown) that fixes the upper case 108 and the lower case 106 is inserted into the screw hole 118. The sealing screws are sealed when the final assembly process of the electricity meter 100 is completed. In this embodiment, the position of the upper case 108 and the lower case 106 when the sealing screw is sealed, that is, when the watt-hour meter 100 is in the final assembly position, is referred to as the final fixed position.

For example, as shown in FIG. 3, the upper opening 114 of the lower case 106 is defined by a side surface 120. The side surface portion 120 extends upward from the board installation surface portion 112 and can also extend downward so as to constitute a rear wall of the terminal fitting accommodating portion 110 on the back side of the lower case 106.

Side portion 120 may include an outer circumferential edge 122 extending circumferentially on the outside thereof. In the final fixed position, the outer circumferential edge 122 can vertically contact an inner circumferential edge 136 of the upper case 108, which will be described later, thereby closing the cavity of the lower case 106.

An engagement convex portion (in other words, a first engagement convex portion) 124 is formed on the lower surface of the outer peripheral edge portion 122 . The engagement convex portion 124 constitutes a fixing portion on the side surface of the housing 105 together with an engagement claw 138 of the upper case 108, which will be described later. In FIGS. 2 and 3, the engaging convex portion 124 is shown only on one of the left and right sides of the lower case 106. As shown in FIG. However, the engaging protrusions 124 can be provided on each of the left and right sides of the lower case 106. The engaging convex portion 124 and the engaging claw 138 are used to fix the upper case 108 and the lower case 106 at the final fixed position.

In the illustrated example, the engaging protrusion 124 has a rib shape. However, the engagement protrusion 124 only needs to have an engagement surface capable of engaging with the engagement claw 138, and its specific shape is not limited to the illustrated example.

Further, the lower case 106 has an engaging protrusion 126 on its back side. The engaging convex portion 126 constitutes a fixing portion on the back side of the housing 105 together with an engaging claw 140 of the upper case 108, which will be described later. As the engagement protrusion 126, in this embodiment, a plurality of pairs (two pairs in the illustrated example) of engagement protrusion 126a and 126b are provided. However, in other embodiments, only the pair of engagement protrusions 126a, 126b may be provided. In each pair, the engaging protrusions 126a, 126b are arranged in alignment with each other in the vertical direction. The first engaging convex portion 126a arranged on the lower side is used to fix the upper case 108 and the lower case 106 at the final fixing position. The second engagement protrusion 126b disposed on the upper side is used to fix the upper case 108 and the lower case 106 at a temporary fixing position different from the final fixing position. In the illustrated example, the engagement protrusion 126 has a rib shape. However, the engagement protrusion 126 only needs to have an engagement surface capable of engaging with the engagement claw 140, and its specific shape is not limited to the illustrated example.

FIG. 4 is a diagram showing the upper case 108 shown in FIG. 1 alone. Upper case 108 has a closed top portion 130 and side portions 132 extending downwardly around top portion 130 . The lower part of the upper case 108 is open. The upper case 108 is configured to fit onto the lower case 106 through the lower opening 134 so as to cover the electronic circuit board disposed on the lower case 106 .

The side surface portion 132 of the upper case 108 includes an inner peripheral edge portion 136 that extends circumferentially inside the side surface portion 132 . An engaging pawl 138 is formed below the inner peripheral edge portion 136. At the final fixed position, the engaging claw 138 can engage with the lower surface of the engaging protrusion 124 on the side surface of the lower case 106. In FIG. 4 , the engaging claws 138 are shown only on one side of the upper case 108 , either left or right. However, the engaging claws 138 can be provided on each of the left and right sides of the upper case 108.

The side surface portion 132 extends downward to have a large length on the back side of the upper case 108. As a result, when the terminal block 110 is fixed to the instrument section 102, the upper case 108 can provide a guard section that protects the boundary between the terminal block 110 and the lower case 106 on the back side of the instrument section 102. can. This can prevent rainwater or the like from entering the terminal block 110 and/or the instrument section 102 through the boundary.

The upper case 108 further has an engaging claw 140 on its back side. The engagement claw 140 engages with the first engagement protrusion 126a of the lower case 106 at the final fixed position. Moreover, the engagement claw 140 engages with the second engagement protrusion 126b of the lower case 106 at the temporary fixing position.

FIG. 5 is a rear perspective view of upper case 108 and lower case 106 in their final fixed position. As shown in FIG. 5, upper case 108 is configured to fit on the outside of lower case 106. As shown in FIG. 6 and 7 are diagrams showing the final fixing position more specifically. For ease of understanding, the left half of the upper case 108 is omitted in FIG. 6. As shown in FIG. 6, in the final fixed position, the outer peripheral edge 122 of the lower case 106 may contact the inner peripheral edge 136 of the upper case 108, thereby causing the lower case 106 (specifically the substrate The cavity portion of the housing portion 109) in which the electronic circuit board and the like are placed is closed. At this time, an engaging claw 138 (not shown in FIG. 6) of the upper case 108 is configured to engage with the lower surface of the engaging protrusion 124 of the lower case 106.

In FIG. 7, the upper case 108 is partially omitted, and the engaged state of the upper case 108 and the lower case 106 on the back side of the power meter 100 is specifically shown. As shown in FIG. 7, at the final fixing position, the engagement claw 140 of the upper case 108 and the first engagement protrusion 126a of the lower case 106 are engaged.

Next, an example of a method for assembling the watt-hour meter 100 including fixing the upper case 108 and the lower case 106 will be specifically described. In this embodiment, when the electricity meter 100 is assembled, the upper case 108 and the lower case 106 can assume two fixed positions: a temporary fixed position and a final fixed position. 8 and 9 are side sectional views of the upper case 108 and the lower case 106, respectively, illustrating the temporary fixing position and the final fixing position.

The upper case 108 and the lower case 106 can be manufactured separately and then fixed in the temporary fixing position shown in FIG. 8 . For example, a terminal fitting or the like may be attached to the lower case 106 before temporary fixing. Thereafter, the upper case 108 is fitted into the lower case 106 until the engaging claw 140 of the upper case 108 engages with the second engaging protrusion 126b of the lower case 106. At this time, the engagement pawl 140 of the upper case 108 rides over the second engagement protrusion 126b due to the elasticity of the material of the upper case 108 and engages with the lower surface of the second engagement protrusion 126b. In the temporary fixing position compared to the final fixing position, the upper case 108 is located above the lower case 106, and therefore, as shown in FIG. It is located above and away from the outer peripheral edge 122 of the case 106. Further, an engaging claw 138 (as shown in FIG. 4, provided below the inner peripheral edge 136 on the side surface side of the housing 105) not shown in FIG. 8 is also located above the outer peripheral edge 122, Therefore, it does not engage with the corresponding engagement protrusion 124. In this way, in the temporary fixing position, the upper case 108 is fixed to the lower case 106 only on the back side of the power meter 100. Therefore, the upper case 108 can be easily removed from the lower case 106. In this state, for example, the watt-hour meter 100 can be held and transported for a final assembly process including attachment of an electronic circuit board and the like.

The engagement between the engagement claw 140 and the second engagement convex portion 126b can be released by pulling the back side (for example, the guard portion) of the upper case 108 in the horizontal direction away from the lower case 106. I can do it. After the engagement is released, upper case 108 is separated from lower case 106. Thereafter, for example, an electronic circuit board and a nameplate are attached to the lower case 106, and then the upper case 108 is fitted to the lower case 106 until the engaging claw 140 engages with the first engaging protrusion 126a. At this time, due to the elasticity of the material of the upper case 108, the engaging claw 140 climbs over the second engaging convex portion 126b and the first engaging convex portion 126a, and enters the first engaging convex portion 126a as shown in FIG. It engages with the lower surface of the convex portion 126a. Further, as shown in FIG. 9, at the final fixed position, the inner peripheral edge 136 of the upper case 108 may be in contact with the outer peripheral edge 122 of the lower case 106. Further, on the side surface side of the housing 105, the engagement claw 138 of the upper case 108 engages with the engagement protrusion 124 of the lower case 106 (see FIG. 10). Thereafter, sealing screws are attached to the upper case 108 and the lower case 106, and the sealing screws are sealed, thereby completing the assembly of the electricity meter 100.

Although the embodiments of the present invention have been described above, the embodiments of the invention described above are for facilitating understanding of the present invention, and are not intended to limit the present invention. For example, in the above embodiment, the fixing part including the second engagement convex part 126b for temporary fixing is provided on the back side of the housing 105, and the remaining fixing part is provided on the side side of the housing 105. ing. However, the remaining fixing portions may be provided on the front side of the housing 105. Alternatively, for example, a fixing part including the second engagement protrusion 126b for temporary fixing may be provided on the side or front side of the housing 105, and the remaining fixing part may be provided on the back side of the housing 105. good.

The present invention may be modified and improved without departing from its spirit, and it goes without saying that the present invention includes equivalents thereof. In addition, any combination or omission of each component described in the claims and specification is possible within the scope of solving at least part of the above-mentioned problems or achieving at least part of the effect. It is.

The present invention includes the following aspects.
1. A casing for a power meter consisting of an upper case with an open bottom and a lower case with an open top,
Equipped with multiple fixing parts to removably fix the upper and lower cases to each other,
Each of the plurality of fixing parts includes an engaging pawl provided on the inner surface of the upper case and a first engaging protrusion that is engageable with the engaging pawl provided on the outer surface of the lower case. , the upper case and the lower case are configured to be fixed in the final assembly position of the watt-hour meter by the engaging claw engaging with the first engaging protrusion,
Some of the fixing parts of the plurality of fixing parts further include a second engagement protrusion that is engageable with the engagement claw provided on the outer surface of the lower case, and the second engagement protrusion is a housing disposed at a position above the first engaging convex portion.
2. Above 1. The casing described in
A casing in which some of the fixing parts are provided on the back side of the casing, and the remaining fixing parts are provided on the front side or side side of the casing.
3. A method for assembling a power meter,
A step of preparing an upper case with an open lower part and a lower case with an open upper part, the first engaging protrusions being arranged on the outer surface of the lower case so as to be aligned in the vertical direction. and a second engagement protrusion located above the first engagement protrusion.
a step of fitting the upper case to the lower case until the engaging claw provided on the inner surface of the upper case engages with the second engaging protrusion;
separating the upper case from the lower case by disengaging the second engagement protrusion and the engagement claw;
a step of fitting the upper case to the lower case again until the engaging claw engages with the first engaging protrusion;
An assembly method comprising the step of sealing sealing screws attached to an upper case and a lower case.

The present invention can be widely applied to power meters including an upper case and a lower case.

D Vertical direction 100 Energy meter 101 Terminal block 101a Distribution line insertion port 102 Instrument section 105 Housing 106 Lower case 108 Upper case 109 Board accommodating section 110 Terminal fitting accommodating section 112 Board installation surface section 114 Upper opening 116 Board support section 118 Screw Hole 120 Side part 122 Outer peripheral edge part 124 Engagement protrusion (first engagement protrusion)
126a First engaging convex portion 126b Second engaging convex portion 130 Upper surface portion 132 Side portion 134 Lower opening 136 Inner peripheral edge portion 138 Engaging claw 140 Engaging claw

Claims (3)

A casing for a power meter consisting of an upper case with an open bottom and a lower case with an open top,
A plurality of fixing parts are provided for removably fixing the upper case and the lower case to each other,
Each of the plurality of fixing parts includes an engaging pawl provided on the inner surface of the upper case, and a first engaging protrusion that is engageable with the engaging pawl provided on the outer surface of the lower case. and configured such that the upper case and the lower case are fixed at a final assembly position of the watt-hour meter by the engaging claw engaging the first engaging protrusion. has been
Some of the fixing parts of the plurality of fixing parts further include a second engagement convex part provided on the outer surface of the lower case and capable of engaging with the engagement claw, and the second engagement protrusion is engageable with the engagement claw. The engagement protrusion is disposed at a position above the first engagement protrusion. The casing according to claim 1,
The casing, wherein some of the fixing parts are provided on the back side of the casing, and the remaining fixing parts are provided on the front side or side side of the casing. A method for assembling a power meter,
A step of preparing an upper case with an open lower part and a lower case with an open upper part, the first engaging protrusions being arranged on the outer surface of the lower case in a vertical direction. and a second engagement protrusion located above the first engagement protrusion.
fitting the upper case into the lower case until an engagement claw provided on the inner surface of the upper case engages with the second engagement protrusion;
separating the upper case from the lower case by disengaging the second engagement protrusion and the engagement claw;
fitting the upper case into the lower case again until the engaging claw engages with the first engaging protrusion;
An assembly method comprising the step of sealing sealing screws attached to the upper case and the lower case.

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