JP6143580B2 - Substrate unit and rice cooker - Google Patents

Description

  The present invention relates to a substrate unit and a rice cooker.

  Conventionally, a liquid crystal display device is provided with a second locking claw with a sharp tip, a rectangular hole is formed in a printed wiring board, and the second locking claw is inserted into this hole. There has been an electronic device in which a liquid crystal display device is attached to a printed wiring board (for example, see Patent Document 1).

JP-A-10-270105 ([0021], [0022], FIG. 1)

  However, in the electronic device of Patent Document 1, the second locking claw (claw portion) is inserted into a rectangular hole (mounting hole), and the flat portion provided at the upper end of the claw portion is hooked on the back surface of the substrate. Attach the nail part to the substrate. For this reason, excessive stress is applied to the corners of the mounting holes when pressing the substrate to be manufactured or when a resin molded part such as a claw is attached to the mounting holes of the substrate. There was a case. In addition, in a finished product (for example, a rice cooker), the force applied when the operation unit provided in the lid or the main body is operated, or the heat generated during rice cooking is transmitted to the substrate and caused by thermal shock. As a result, excessive stress is applied to the corners of the mounting holes, and cracks or the like starting from the corners may occur.

  The present invention has been made against the background of the above problems, and an object of the present invention is to provide a substrate unit and a rice cooker that reduce problems caused by stress applied to the substrate.

The substrate unit of the present invention includes a substrate on which an attachment hole is formed, and a resin molded part that has a claw portion and is attached to the substrate by inserting the claw portion into the attachment hole. R corners or C chamfers are applied to the corners of the mounting holes, and at least one of the two side surfaces is in contact with the inner surface of the mounting hole. The protrusion part protruded to the outer side which fills the clearance gap between parts is provided .

  The rice cooker of this invention is provided with the cover body and the main body to which the said cover body is attached so that opening and closing is possible, and said board | substrate unit is attached to the said cover body or the said main body.

  According to the present invention, there is provided a substrate having a board having a mounting hole formed thereon, and a resin molded part that has a claw part and is attached to the board by inserting the claw part into the mounting hole. The corner of the hole is rounded or chamfered. For this reason, even if the nail | claw part of a resin molded component is inserted in an attachment hole, it can suppress that stress concentrates on the corner | angular part of an attachment hole and a crack arises. Therefore, it is possible to reduce problems caused by applying stress to the substrate.

1 is an overall perspective view of a rice cooker 100 according to Embodiment 1. FIG. It is a top view of the rice cooker 100 which concerns on Embodiment 1. FIG. It is a longitudinal cross-sectional view of the rice cooker 100 which concerns on Embodiment 1. FIG. It is a perspective view of the substrate unit 40 of the rice cooker 100 according to the first embodiment. It is an external view of the substrate unit 40 of the rice cooker 100 according to the first embodiment. It is a figure which shows the attachment hole 42a and the nail | claw part 44a of the rice cooker 100 which concern on Embodiment 1. FIG. It is a figure which shows the attachment hole 42a and the nail | claw part 44a of the rice cooker 100 which concern on Embodiment 2. FIG. It is a figure which shows the attachment hole 42a and the nail | claw part 44a of the rice cooker 100 which concern on Embodiment 3. FIG. It is a figure which shows the attachment hole 42a and the nail | claw part 44a of the rice cooker 100 which concern on Embodiment 4. FIG. It is a figure which shows the direction of the protrusion part 44a1 which comprises the pair of the nail | claw part 44a of the rice cooker 100 which concerns on Embodiment 5. FIG. It is a figure which shows the direction of the protrusion part 44a1 which comprises the pair of the nail | claw part 44a of the rice cooker 100 which concerns on Embodiment 6. FIG. It is a figure which shows the attachment hole 42a and the nail | claw part 44a of the rice cooker 100 which concern on Embodiment 7. FIG. It is a figure which shows the nail | claw part 44a of the rice cooker 100 which concerns on Embodiment 8. FIG. It is a figure which shows the attachment hole 42a of the rice cooker 100 which concerns on Embodiment 9. FIG. It is a figure which shows the attachment hole 42a of the rice cooker 100 which concerns on Embodiment 10. FIG. It is a figure which shows an example of the nail | claw part of the rice cooker which concerns on a comparative example. It is a figure which shows the other example of the nail | claw part of the rice cooker which concerns on a comparative example.

  Hereinafter, rice cooker 100 according to an embodiment of the present invention will be described. In addition, this invention is not limited by the form of drawing shown below. In the following description, terms representing positions (for example, “upper”, “lower”, etc.) are used as appropriate for ease of understanding. The invention is not limited.

Embodiment 1 FIG.
1 is an overall perspective view of a rice cooker 100 according to Embodiment 1. FIG. FIG. 2 is a plan view of rice cooker 100 according to the first embodiment. FIG. 3 is a longitudinal sectional view of rice cooker 100 according to the first embodiment. FIG. 4 is a perspective view of substrate unit 40 of rice cooker 100 according to the first embodiment. FIG. 5 is an external view of the substrate unit 40 of the rice cooker 100 according to the first embodiment.

  As shown in FIG. 1, the rice cooker 100 includes a main body 1 and a lid body 4 that is attached to an upper portion of the main body 1 so as to be freely opened and closed. A lid opening / closing button 5 is provided on the front surface of the lid body 4. As shown in FIGS. 1 and 2, a plurality of operation units 2 and a transmission unit 10 are provided on the upper surface of the lid 4. At least a part of the lid 4 is transparent so that the transmissive part 10 can visually recognize the inside of the lid 4 through this portion. For this reason, the user can confirm the display part (illustration omitted) provided under the transmissive part 10 through the transmissive part 10.

  As shown in FIG. 3, the upper surface of the main body 1 is opened so that the inner pot 3 is installed, and the inner pot 3 is installed in this opening. Below the bottom surface of the inner pot 3, a temperature sensor 13 for detecting the temperature of the inner pot 3 and an induction heating coil 12 for induction heating the inner pot 3 are provided. The temperature sensor 13 is composed of, for example, a thermistor.

  On the back side of the main body 1, a control board 20 that controls the heating power of the induction heating coil 12 based on the temperature detected by the temperature sensor 13 is provided. On the front side of the main body 1, a steam recovery tank 21 that recovers steam generated by heating an object to be heated inside the inner pot 3 is provided.

  An inner lid 8 is detachably attached to the lid body 4. A lid packing 8 a that seals the upper opening of the inner pot 3 when the lid 4 is closed is attached to the outer peripheral portion of the inner lid 8. A substrate unit 40 is provided on the lid 4.

  As shown in FIG. 4, the substrate unit 40 includes a substrate 42, a liquid crystal display element 43, a liquid crystal attachment member 44, and an operation unit 45. The liquid crystal attachment member 44 is a member formed of resin and has a plurality of claw portions 44a. The operation unit 45 is provided corresponding to the operation unit 2. The liquid crystal attachment member 44 corresponds to the resin molded part of the present invention. In the first embodiment, the configuration in which the operation unit 2 is provided in the lid 4 has been described. However, the operation unit 2 may be provided in the main body 1. In this case, the board unit 40 is provided in the main body 1.

  As shown in FIG. 5, a plurality of mounting holes 42 a for mounting the liquid crystal mounting member 44 are formed in the substrate 42. A claw portion 44a formed of resin is inserted into the mounting hole 42a. The mounting hole 42a is rounded. Hereinafter, this will be described in detail with reference to FIG. The specific number of the mounting holes 42a is not limited to the number shown in the figure.

  FIG. 6 is a diagram showing the mounting holes 42a and the claw portions 44a of the rice cooker 100 according to the first embodiment. The corner 42a1 of the mounting hole 42a is rounded. Therefore, even when stress is applied to the corner portion 42a1 of the mounting hole 42a when the substrate 42 is pressed or when the claw portion 44a is attached to the mounting hole 42a, the stress is prevented from concentrating on the corner portion 42a1. be able to. Therefore, the occurrence of cracks and the like can be suppressed starting from the corner portion 42a1. In addition, about 0.5 mm is suitable for the radius of this R removal. Here, the nail | claw part 44a is comprised by the hook-shaped or wedge-shaped member which can be elastically deformed, for example. The attachment hole 42a is sized to allow the claw portion 44a to be inserted.

  As described above, since the corner portion 42a1 of the mounting hole 42a is rounded, a clearance (gap) is required between the both side surfaces of the claw portion 44a and the mounting hole 42a. Since the liquid crystal display element 43 moves when the liquid crystal attachment member 44 moves, it is desirable that the liquid crystal attachment member 44 be firmly attached to the substrate 42.

  Therefore, the protruding portions 44a1 are provided on both side surfaces of the claw portion 44a. The protruding amount of the protruding portion 44a1 is preferably equivalent to the radius of the R removal of the corner portion 42a1 of the mounting hole 42a. Accordingly, the side surface of the claw portion 44a and the inner surface of the mounting hole 42a come into contact with each other, and the claw portion 44a can be reliably hooked to the mounting hole 42a without riding on the curved portion of the R-shape. Thus, rattling can be suppressed by providing the protrusion 44a1 on the claw 44a.

FIG. 16 is a diagram illustrating an example of a claw portion 144a of a rice cooker according to a comparative example.
Drawing 17 is a figure showing other examples of claw part 144a of a rice cooker concerning a comparative example.

  Here, as shown in FIG. 16, it is also conceivable that the corner 142a1 of the mounting hole 142a of the substrate 142 has a right angle. In this case, the claw portion 144 a having a sharp tip is inserted into the mounting hole 142 a of the substrate 142, and the flat portion provided at the upper end of the claw portion 144 a is hooked on the back surface of the substrate 142. Thus, the claw portion 144a is attached to the substrate 142. In such a conventional resin molded part mounting structure, excessive stress is applied to the corner 142a1 of the mounting hole 142a when the substrate 142 is pressed or when the resin molded part is mounted in the mounting hole 142a of the board 142. In some cases, cracks and the like may occur starting from the corner 142a1. Moreover, also in the product (for example, rice cooker) in which the substrate unit 40 is mounted, the force applied when the operation unit provided in the rice cooker is operated, or the heat generated by the heating during the rice cooking is given to the substrate 142. Similar defects may occur due to impact.

  Further, as shown in FIG. 17, a claw portion 144a having a conical cotter pin shape is inserted into a circular mounting hole 142a formed in a substrate (not shown), and is provided at the upper end of the claw portion 144a. The flat portion is supported by being hooked on the back surface of the substrate 142. In another example of such a conventional resin molded part mounting structure, since no corners are formed in the mounting hole 142a, cracks and the like are less likely to start from there, but the structure of the claw part 144a of the resin molded part Is complicated and requires space on the substrate.

  On the other hand, the board unit 40 according to the first embodiment includes the board 42 in which the mounting hole 42a is formed and the claw part 44a, and the claw part 44a is inserted into the mounting hole 42a, whereby the board 42 is provided. A liquid crystal attachment member 44 attached to the substrate 42, and a corner 42a1 of the attachment hole 42a of the substrate 42 is rounded. For this reason, even if the nail | claw part 44a of the liquid-crystal attachment member 44 is inserted in the attachment hole 42a, it can suppress that stress concentrates on the corner | angular part 42a1 of the attachment hole 42a, and a crack arises. Therefore, the influence due to the stress applied to the substrate 42 can be reduced.

  Further, even when the substrate unit 40 of the first embodiment is mounted on the rice cooker 100, the operation unit 45 provided in the lid 4 is operated because the substrate unit 40 has the above-described configuration. In addition, it is possible to reduce problems caused by the thermal shock applied to the substrate 42 by the force applied to the substrate 42 and the heat generated by heating during rice cooking.

  Moreover, since the protrusion part 44a1 is provided in the both sides of the nail | claw part 44a, the clearance gap between the attachment hole 42a and the nail | claw part 44a can be filled. Therefore, rattling of the claw portion 44a can be suppressed and the claw portion 44a and the mounting hole 42a can be reliably engaged.

Embodiment 2. FIG.
FIG. 7 is a diagram showing the attachment holes 42a and the claw portions 44a of the rice cooker 100 according to the second embodiment. As shown in FIG. 7, in the second embodiment, unlike the first embodiment, the corner portion 42 a 1 of the mounting hole 42 a is chamfered. For this reason, compared with the case where the corner | angular part 42a1 of the attachment hole 42a is made into a right angle like before, stress concentration can be suppressed and generation | occurrence | production of the crack etc. which use the corner | angular part 42a1 as a starting point can be suppressed. Therefore, the influence due to the stress applied to the substrate 42 can be reduced.

Embodiment 3 FIG.
FIG. 8 is a diagram showing the mounting holes 42a and the claw portions 44a of the rice cooker 100 according to the third embodiment. As shown in FIG. 8, in the third embodiment, unlike in the first embodiment, the protruding portion 44a1 is provided only on one side surface of the claw portion 44a. For this reason, the mold structure of the claw portion 44a is simplified, the reliability of the mold can be improved, and an inexpensive product can be obtained.

Embodiment 4 FIG.
FIG. 9 is a diagram showing the mounting holes 42a and the claw portions 44a of the rice cooker 100 according to the fourth embodiment. As shown in FIG. 9, in the fourth embodiment, unlike in the third embodiment, the corner portion 42a1 of the mounting hole 42a is chamfered. For this reason, compared with the case where the corner | angular part 42a1 of the attachment hole 42a is made into a right angle like before, stress concentration can be suppressed and generation | occurrence | production of the crack etc. which use the corner | angular part 42a1 as a starting point can be suppressed.

Embodiment 5. FIG.
FIG. 10 is a diagram illustrating the direction of the protruding portion 44a1 that forms a pair of the claw portions 44a of the rice cooker 100 according to the fifth embodiment. As FIG. 10 shows, this Embodiment 5 is a structure which suppresses shakiness in case the protrusion part 44a1 is one side. Specifically, the protruding portion 44a1 of the claw portion 44a is brought into contact with the outer side and the outer side of the paired corner portion 42a1. For example, the mounting hole 42a in FIG. 10 (a) corresponds to the left mounting hole 42a on the back side in FIG. 5, and the mounting hole 42a in FIG. 10 (b) is the right mounting on the back side in FIG. It corresponds to the hole 42a. It is comprised so that the surface on the opposite side of the surface in which each protrusion part 44a1 of a pair of nail | claw part 44a is provided may oppose. In this way, the gap in the rattling direction between the substrate 42 and the liquid crystal display element 43 can be filled, and shakiness of the liquid crystal display element 43 can be suppressed.

Embodiment 6 FIG.
FIG. 11 is a diagram illustrating the direction of the protruding portion 44a1 forming a pair of the claw portions 44a of the rice cooker 100 according to the sixth embodiment. As FIG. 11 shows, this Embodiment 6 is a structure which suppresses shakiness in case the protrusion part 44a1 is one side. Specifically, the protruding portion 44a1 of the claw portion 44a is brought into contact with the inner side and the inner side of the paired mounting holes 42a. For example, the mounting hole 42a in FIG. 11 (a) corresponds to the left mounting hole 42a on the back side in FIG. 5, and the mounting hole 42a in FIG. 11 (b) is the right mounting on the back side in FIG. It corresponds to the hole 42a. It is comprised so that the surface in which each protrusion part 44a1 of a pair of nail | claw part 44a is provided opposes. Thus, the gap in the rattling direction between the substrate 42 and the claw portion 44a can be filled, and rattling of the claw portion 44a can be suppressed.

Embodiment 7 FIG.
FIG. 12 is a diagram showing the attachment holes 42a and the claw portions 44a of the rice cooker 100 according to the seventh embodiment. As shown in FIG. 12, the projecting portion 44a1 is formed with an inclined surface 44a2 so that the claw width decreases toward the tip of the claw portion 44a. The inclined surface 44a2 is formed so that the width becomes narrower toward the tip of the protruding portion 44a1. Thus, it becomes easy to insert the tip of the claw portion 44a into the mounting hole 42a. The inclined surface 44a2 may have a straight shape as shown in the figure or a curved shape.

  As shown in FIG. 12, the most proximal portion of the inclined surface 44a2 formed on the claw portion 44a is below the surface of the substrate 42 (generally called the component surface) in FIG. It is desirable to be configured to be on the side. The most proximal portion of the inclined surface 44a2 is located on the tip side of the surface of the substrate 42 in a state where the liquid crystal attachment member 44 is attached to the substrate 42, so that the vertical portion of the protrusion 44a1 is the attachment hole. It abuts against the hole edge of 42a. If comprised in this way, the length of inclined surface 44a2 can be enlarged, and an inclination angle can be made loose. For this reason, it is easy to insert the tip of the claw portion 44a, and rattling between the substrate 42 and the claw portion 44a is less likely to occur.

Embodiment 8 FIG.
FIG. 13 is a diagram illustrating the claw portion 44a of the rice cooker 100 according to the eighth embodiment. As shown in FIG. 13, in the eighth embodiment, a guide hole 42 b is formed in the substrate 42. The liquid crystal attachment member 44 is provided with a guide portion (not shown) that is inserted into the guide hole 42b. A guide part is comprised, for example with a rod-shaped member. By inserting the guide portion into the guide hole 42b, when inserting the claw portion 44a into the attachment hole 42a, it is not necessary to consider the gap formed between the attachment hole 42a and the claw portion 44a, and the liquid crystal attachment member 44 positioning can be performed. And since the nail | claw part 44a is inserted in the attachment hole 42a in the positioned state, the rattling between the board | substrate 42 and the nail | claw part 44a can be suppressed.

Embodiment 9 FIG.
FIG. 14 is a diagram showing the mounting holes 42a of the rice cooker 100 according to the ninth embodiment. As shown in FIG. 14, in the ninth embodiment, unlike the first embodiment, the corner portion 42a1 of the mounting hole 42a is rounded only on the flat portion side of the claw portion 44a. . Here, the plane portion side of the claw portion 44a means the locking portion protruding direction of the claw portion 44a in a state where the claw portion 44a is viewed in plan. This is because a portion to which stress is applied is concentrated near the tip of the flat portion of the claw portion 44a. Thus, the structure of the substrate mold can be simplified, and a mold with improved reliability can be obtained.

Embodiment 10 FIG.
FIG. 15 is a diagram showing the mounting holes 42a of the rice cooker 100 according to the tenth embodiment. As shown in FIG. 15, in the tenth embodiment, a corner 42a1 of the mounting hole 42a is cut out so that a curved surface is provided. In this way, stress concentration on the corner 42a1 can be dispersed.

  In addition, in each embodiment, although the example in which the board | substrate unit 40 was mounted in the rice cooker 100 was demonstrated, the board | substrate unit 40 may be mounted in other products.

  In each embodiment, the liquid crystal attachment member 44 is described as an example of the resin molded part. However, the present invention is not limited to this, and any resin molded part attached to the attachment hole 42a may be used.

  In each embodiment, although rice cooker 100 provided with steam recovery tank 21 was explained, it can be applied also to rice cooker 100 where steam recovery tank 21 is not provided.

  DESCRIPTION OF SYMBOLS 1 Main body, 2 Operation part, 3 Inner pan, 4 Lid body, 5 Lid opening / closing button, 8 Inner lid, 8a Lid packing, 10 Transmission part, 12 Induction heating coil, 13 Temperature sensor, 20 Control board, 21 Steam recovery tank, 40 Substrate unit, 42 Substrate, 42a Mounting hole, 42a1 Corner portion, 42b Guide hole, 43 Liquid crystal display element, 44 Liquid crystal mounting member, 44a Claw portion, 44a1 Projection portion, 44a2 Inclined surface, 45 Operation portion, 100 Rice cooker, 142 Substrate, 142a mounting hole, 142a1 corner, 144a claw.

Claims (8)

A substrate with mounting holes formed;
A resin molded part that has a claw part and is attached to the substrate by inserting the claw part into the attachment hole,
The corners of the mounting holes of the board are rounded or chamfered ,
The claw portion is provided with at least one of both side surfaces provided with a protruding portion that abuts the inner surface of the mounting hole and protrudes to fill a gap between the mounting hole and the claw portion. A board unit characterized by A substrate with mounting holes formed;
A resin molded part that has a claw part and is attached to the substrate by inserting the claw part into the attachment hole,
The corner portion of the mounting hole of the substrate is cut out to give a curved surface ,
The claw portion is provided with at least one of both side surfaces provided with a protruding portion that abuts the inner surface of the mounting hole and protrudes to fill a gap between the mounting hole and the claw portion. A board unit characterized by In what the projection part is provided only on one side of the claw part,
The nail portion is
3. The substrate unit according to claim 1, wherein at least one pair is provided so that the side surfaces on which the protruding portions are provided are opposed to each other. In what the projection part is provided only on one side of the claw part,
The nail portion is
3. The substrate unit according to claim 1, wherein at least one pair is provided so that a side surface opposite to the side surface on which the protruding portion is provided is disposed opposite to the side surface. The protrusion is
Board unit according to any one of claims 1 to 4, characterized in that it has an inclined surface that tapers toward the tip. The most proximal end portion of the inclined surface is located on the front end side of the mounting hole with respect to the surface of the substrate in a state where the resin molded component is mounted on the substrate. 5. The board unit according to 5 . Guide holes are formed in the substrate,
The substrate unit according to any one of claims 1 to 6 , wherein the resin molded component is provided with a guide portion to be inserted into the guide hole. A lid,
A body to which the lid is attached so as to be freely opened and closed,
Board unit according to any one of claims 1 to 7, rice cookers, characterized in that attached to the lid or the body.

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