JP2012203989A - Waterproof structure of operation panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waterproof structure suitable for an operation panel of a non-portable electronic apparatus such as an image forming device.SOLUTION: A rubber key 17 is arranged to cover an upper side of a circuit substrate 15, and a first skirt part 17C extending on a lower side than the circuit substrate 15 is provided at a portion of the rubber key 17 corresponding to an outer edge 15A of the circuit substrate 15 to cover the outer edge 15A. Furthermore, a groove part 23A extending along a lower end of the first skirt part 17C is provided at a lower side of the first skirt part 17C. Thereby, an upper side of the circuit substrate 15 is covered with the rubber key 17, and therefore, the circuit substrate 15 is not directly immersed with water, and the circuit substrate 15 is protected from the water. Even if the operation panel 13 is immersed with water, the water does not flow to the circuit substrate 15, is introduced to the lower side than the circuit substrate 15 by the first skirt part 17C, and then, is collected at the groove part 23A and drained.

Description

  The present invention relates to a waterproof structure for an operation panel.

  For example, in the invention described in Patent Document 1, a watertight casing that covers the entire circuit board by sandwiching the circuit board between a cover plate made of an elastically deformable material such as rubber and a bottom plate made of a hard resin. Is configured.

Japanese Patent Laid-Open No. 2001-82007

However, it is not appropriate to apply the waterproof structure described in Patent Document 1 to an operation panel of an electronic device such as a printer as it is.
That is, the invention described in Patent Document 1 is a waterproof structure of a circuit board built in a portable small electronic device such as a wireless key, and a waterproof structure suitable for an operation panel of a non-portable electronic device such as a printer. Is hard to say.

  In view of the above points, an object of the present invention is to provide a waterproof structure suitable for an operation panel of a non-portable electronic device.

  In order to achieve the above object, the present invention is arranged so as to cover the circuit board (15) on which the electric circuit is formed and the upper side of the circuit board (15), and is elastic in response to the operation force from the user. A deformable elastic key (17), and a portion of the elastic key (17) corresponding to the outer edge of the circuit board (15) extends downward from the circuit board (15) so as to cover the outer edge. A skirt portion (17C) is provided, and a groove portion (23A) extending along the lower end of the skirt portion (17C) is provided on the lower side of the skirt portion (17C). .

  Accordingly, in the present invention, since the upper side of the circuit board (15) is covered with the elastic key (17), the circuit board (15) is not directly covered with water, and the circuit board (15). Is protected from flooding. If the operation panel is submerged, the water does not flow to the circuit board (15), but is guided downward from the circuit board (15) by the skirt part (17C), and then the groove (23A ) And drain.

  As described above, in the present invention, unlike the invention described in Patent Document 1, it is possible to obtain a practically sufficient waterproof capability without using a completely sealed structure, which is suitable for an operation panel of a non-portable electronic device. A waterproof structure can be obtained.

  The skirt portion (17C) is, for example, formed integrally with the elastic key (17), or a base member (23) formed of a material harder than the elastic key (17) on the lower side of the circuit board (15). And the groove (23A) may be provided in the base member (23).

  Incidentally, the reference numerals in parentheses for each of the above means are examples showing the correspondence with the specific means described in the embodiments described later, and the present invention is indicated by the reference numerals in the parentheses of the above respective means. It is not limited to specific means.

1 is an external perspective view of an image forming apparatus 1 according to an embodiment of the present invention. It is a top view of the operation panel 13 which concerns on embodiment of this invention. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. (A) is the elements on larger scale of FIG. 4, (b) is the elements on larger scale of FIG. It is the boss | hub part 17H which concerns on 1st Embodiment of this invention, and the expanded sectional view of the circumference | surroundings. It is the boss | hub part 17H which concerns on 2nd Embodiment of this invention, and the expanded sectional view of the circumference | surroundings. It is a figure which shows the characteristic of the rubber key 17 which concerns on 3rd Embodiment of this invention.

In this embodiment, the waterproof structure of the operation panel according to the present invention is applied to the image forming apparatus 1 having both a printing function and an image reading function. The embodiment will be described below with reference to the drawings.
(First embodiment)
1. Outline of Image Forming Apparatus As shown in FIG. 1, an image forming apparatus 1 according to this embodiment includes an image reading unit 5 integrated with an upper side of an image forming unit 3. Between the unit 5, there is provided a discharge port 7 through which a recording sheet (hereinafter referred to as a sheet) such as a recording sheet or an OHP sheet that has undergone image formation (printing) in the image forming unit 3 is discharged. .

  The image forming unit 3 according to the present embodiment includes an electrophotographic image forming unit that forms an image on a sheet by transferring a developer image onto the sheet, and the image reading unit 5 is in a stationary state. An image reading unit having an image reading function of a flat bed method for reading an image of a placed document and an automatic reading function of reading an image of a document while automatically feeding the document to an auto document feeder (automatic document feeder). .

  An operation panel 13 having an inclined surface 13A inclined with respect to the horizontal direction is provided on the discharge port 7 side (front side in this embodiment) of the upper side of the image forming unit 3. On the inclined surface 13A of the operation panel 13, various operation keys 9 and a display panel 11 for displaying information are provided.

  Incidentally, in the image forming apparatus 1 according to the present embodiment, as the operation key 9, for example, as shown in FIG. 2, the numeric keypad 9 </ b> A used when inputting numbers and the display content of the display unit 11 are selected or switched. A selection key 9B, a mode selection key 9C for selecting an operation mode of the image forming apparatus 1, and the like are provided.

2. Operation Panel Prevention Structure As shown in FIG. 1, the operation panel 13 is a strip extending in a horizontal direction (left and right direction in this embodiment) orthogonal to the opening direction of the discharge port 7 (front and rear direction in this embodiment). As shown in FIG. 3, the panel portion includes a circuit board 15, a rubber key 17, a first cover 19 and a second cover 21 that cover the upper side of the rubber key 17, a base member 23, and the like.

  The circuit board 15 is an electric board on which an electric circuit for receiving an operation of the operation key 9 and generating an electric signal corresponding to the operation is formed. The circuit board 15 includes the second cover 21 (the inclined surface 13A) and It is arranged in an inclined state with respect to the vertical direction so as to be substantially parallel.

  The rubber key 17 is arranged so as to cover the upper side of the circuit board 15 and is an elastic key that transmits the operation force to the circuit board 15 while elastically deforming in response to the operation force from the user. The plate portion 17A substantially parallel to the circuit board 15 and the operation projection portion 17B that directly receives an operation force by protruding upward from the plate portion 17A and touched by the user are configured. For this reason, in this embodiment, the operation projection 17B itself constitutes the operation key 9.

  A portion of the rubber key 17 corresponding to the lower end side outer edge portion (hereinafter referred to as the lower end portion) 15A of the circuit board 15 is a first skirt portion extending downward from the circuit board 15 so as to cover the lower end portion 15A. 17C is provided, and the first skirt portion 17C is integrally formed of an elastic material such as silicone rubber together with the plate portion 17A and the operation projection portion 17B.

  Incidentally, the base part of the operation projection part 17B of the rubber key 17 contacts a switch part (not shown) provided on the circuit board 15 when the tip of the operation projection part 17B is pressed by the user. A pressing projection 17D for pressing the switch portion is provided, and a recess 17E for forming a space between the pressing projection 17D and the circuit board 15 is formed around the pressing projection 17D.

  Further, the first cover 19 is a cover member that covers the upper side of the plate portion 17A and is provided with a through hole 19A through which the operation projection portion 17B penetrates. In addition, a first holding hook 19B and a second holding hook 19C are provided for supporting (holding) the circuit board 15 so as to be suspended.

  That is, the first cover 19 has a first cover main body 19D, a second skirt portion 19E, a first holding hook 19B, and a second holding hook 19C. These 19A to 19E are harder than the rubber key 17. (For example, polystyrene).

  The first cover main body 19D is a substantially plate-like portion disposed in a state inclined with respect to the vertical direction along the circuit board 15, and a second skirt is formed at the lower end of the first cover main body 19D. A portion 19E and a first holding hook 19B are provided, and a second holding hook 19C is provided on the upper end side.

  The second skirt portion 19E extends in the same direction as the first skirt portion 17C so as to cover the first skirt portion 17C from above, and a first holding hook 19B is provided on the second skirt portion 19E. .

  Note that the first holding hook 19B and the second holding hook 19C are not provided in the entire extending direction of the operation panel 13 (hereinafter referred to as the width direction), but are provided discretely and at a plurality of locations. As shown in FIG. 3, there is a portion where both holding hooks 19B and 19C are not provided.

  For this reason, the first skirt portion 17 </ b> C and the second skirt portion 19 </ b> E extend straight downward in a direction orthogonal to the circuit board 15 in the portion where the holding hooks 19 </ b> B and 19 </ b> C are not provided.

  On the other hand, in the part where both holding hooks 19B and 19C are provided, as shown in FIG. 4, the first skirt portion 17C and the second skirt portion 19E are bent in a crank shape so as to avoid the first holding hook 19B. However, it extends downward in the direction orthogonal to the circuit board 15.

  However, the second skirt portion 19E macroscopically extends in the same direction as the first skirt portion 17C so as to cover the first skirt portion 17C from the upper side regardless of the presence or absence of both holding hooks 19B and 19C. It has a configuration. For this reason, the first skirt portion 17C and the second skirt portion 19E are formed in a wall shape continuously connected over substantially the entire width direction so as to cover the entire area of the circuit board 15 on the lower end portion 15A side.

  That is, the first holding hook 19B has a shape extending from the substantially central portion in the extending direction of the second skirt portion 19E to the circuit board 15 side so as to branch from the second skirt portion 19E. As shown in FIG. 5A, a support claw 19F that protrudes from the second skirt portion 19E side to the lower surface side of the circuit board 15 and supports the circuit board 15 is provided on the front end side (lower end side) in the extending direction. Yes.

On the other hand, in the portion corresponding to the support claw 19F in the first skirt portion 17C, a recess 17F that is depressed in the protruding direction of the support claw 19F is formed so as to cover the support claw 19F.
For this reason, portions of the first skirt portion 17C and the second skirt portion 19E where the holding hooks 19B and 19C are provided are bent into a crank shape as shown in FIG. The portion where the holding hooks 19B and 19C are not provided has a shape extending straight downward in a direction orthogonal to the circuit board 15, as shown in FIG.

  The base member 23 is a part of a housing that supports a load acting on the operation panel 13 formed of a resin harder than the rubber key 17 (polystyrene in the present embodiment). The base member 23 is a circuit board. The first cover 19 is supported from the lower side by being disposed on the lower side.

  A groove portion 23A formed in a substantially U shape so as to surround the lower end portions 17G and 19G of the skirt portions 17C and 19E is provided at a portion corresponding to the lower side of the skirt portions 17C and 19E of the base member 23. The groove 23A is provided and extends over substantially the entire region in the width direction along the lower ends 17G and 19G of the skirts 17C and 19E.

  For this reason, in the present embodiment, the lower end portions 17G and 19G of both skirt portions 17C and 19E are surrounded by the groove portion 23A and positioned in the groove portion 23A, while the upper end 23B of the groove portion 23A is the both skirt portions 17C. , 19E is located above the lower end portions 17G and 19G.

  That is, the groove portion 23A is substantially U-shaped including a pair of side wall portions 23E spaced apart in the horizontal direction (the front-rear direction in the present embodiment) and a bottom portion 23F closing the lower side so as to connect the lower side of the side wall portions 23E. It has a cross-sectional shape. And when both skirt parts 17C and 19E are seen from a horizontal direction, the lower end parts 17G and 19G are located in the site | part which overlaps with the side wall 23E so that it may be pinched | interposed by a pair of side wall 23E.

  The groove 23A is inclined with respect to the vertical direction so that one end side in the extending direction (left and right direction in this embodiment) is lower than the other end side in the extending direction, and is orthogonal to the extending direction. It is set so that one end side in the horizontal direction (in this embodiment, the front-rear direction) is lower than the other end side.

  Specifically, the groove portion 23A according to this embodiment extends in the left-right direction so that the left end side is lower than the right end side, and the groove shape (U shape) is set so that the front side is lower than the rear side. Has been. And the discharge port 23C which discharges liquids, such as water which flowed into the groove part 23A, is provided in the lowest end part (this embodiment front of the left end side) of the groove part 23A.

  The first cover 19 is fixed to the base member 23, the circuit board 15 is held in a state of being suspended from the first cover 19, and the second cover 21 is in a state of being locked to the locking portion 19H. The first cover 19 is assembled. Incidentally, the 2nd cover 21 is a design panel which comprises an external appearance design surface.

  By the way, as shown in FIG. 6, the rubber key 17 is integrally formed with a protruding boss portion 17H protruding toward the circuit board 15, while the circuit board 15 has a hole 15A into which the boss portion 17H is fitted. Is provided. When the boss portion 17H is fitted into the hole portion 15B, the rubber key 17 is positioned with respect to the circuit board 15, and the hole portion 15B is closed so as to be covered with the boss portion 17H.

  That is, the boss portion 17H is formed into a solid round bar or a cup shape (in this embodiment, a cup shape) closed at one end side, and is hat-shaped by the boss portion 17H and the plate portion 17A around the boss portion 17H. Since the plug (plug) is configured, when the boss portion 17H is fitted into the hole portion 15B, the hole portion 15B is covered with the rubber key 17.

  In addition, the boss portion 17H according to the present embodiment is formed in a cup shape recessed toward the circuit board 15, and the first cover 19 is provided with a protruding portion 19J that fits into the recess of the boss portion 17H. In this embodiment, the circuit board 15 and the rubber key 17 are positioned with respect to the first cover 19 by the protrusion 19J.

  The first holding hook 19B and the second holding hook 19C are mainly intended to suspend and support the circuit board 15 and the like, and the positioning of the circuit board 15 and the like with respect to the first cover 19 is fitted into the hole 15B. This is done by fitting the projection 19J into the recess of the boss 17H.

  Incidentally, the boss portion 17H and the hole portion 15B are provided in a portion shifted in the width direction with respect to the operation projection portion 17B. In the present embodiment, the boss portion 17H and the hole portion 15B are shifted in the width direction. At least two locations.

  Further, as shown in FIG. 4, the base member 23 is integrally formed with a column portion 23 </ b> D that protrudes from the lower surface side to the circuit board 15 side, and this column portion 23 </ b> D receives an excessive load on the operation panel 13. In doing so, the circuit board 15 is supported from the lower side, thereby suppressing the circuit board 15 from being greatly bent and deformed.

3. Features of Image Forming Apparatus 1 According to the Present Embodiment (Particularly, Waterproof Structure of Operation Panel 13) In this embodiment, the upper side of the circuit board 15 is covered with a rubber key 17, as shown in FIG. The circuit board 15 is not directly exposed to water, and the circuit board 15 is protected from water. And, if the operation panel 13 gets wet, the water does not flow to the circuit board 15 and is guided to the lower side from the circuit board 15 by the first skirt portion 17C, and then gathers in the groove 23A. Drained from the outlet 23C.

  As described above, according to the present embodiment, a waterproof structure suitable for the operation panel 13 of the image forming apparatus 1 can be obtained because a practically sufficient waterproof capability can be obtained without the operation panel 13 having a completely sealed structure. Can be.

  Further, the present embodiment is characterized in that the upper end of the groove portion 23A is set above the lower ends 17G and 19G of the first skirt portion 17C and the second skirt portion 19E. Water can be reliably guided from the two skirt portion 19E to the groove portion 23A, and the circuit board 15 can be reliably prevented from getting wet.

  Further, since the upper end 23E of the groove 23A is set above the lower end 17G of the first skirt portion 17C, the lower end side of the first skirt portion 17C is fitted into the groove 23A, and the space in the groove 23A is reduced. It becomes a maze structure (labyrinth structure).

  For this reason, a space (for example, a passage shown by a broken line in FIG. 3) from the outside to the circuit board 15 is meandered, and a substantial electrical insulation distance to the circuit board 15 is increased. Thus, the circuit board 15 can be effectively protected from static electricity discharged from the circuit.

  In addition, the part in which the recessed part 17F was provided among the 1st skirt parts 17C becomes a maze structure meandering larger compared with the part in which the recessed part 17F is not provided so that FIG. 4 may show. For this reason, in this embodiment, since the labyrinth structure is provided in the entire width direction, the circuit board 15 can be reliably protected from static electricity or the like.

  In the present embodiment, since the first cover 19 is provided with a second skirt portion 19E extending downward toward the groove portion 23A, as shown in FIGS. 3 and 4, a rubber key is provided. A double structure in which the second skirt portion 19E of the first cover 19 is provided on the first skirt portion 17C of the 17 can prevent the circuit board 15 from getting wet.

  In the present embodiment, the first cover 19 and the second skirt portion 19E are integrally formed of a material harder than the rubber key 17, and the lower surface of the circuit board 15 is formed on the first cover 19 from the second skirt portion 19E side. A support claw 19F that protrudes to the side and supports the circuit board 15 is provided, and a recess 17F that is recessed in the protruding direction of the support claw 19F is formed in the first skirt portion 17C so as to cover the support claw 19F. It is characterized by having.

  Accordingly, in the present embodiment, as shown in FIG. 5A, the circuit board 15 side of the support claw 19F is covered with the recess 17F formed in the first skirt portion 17C. Even when 13 is flooded and the water flows along the support claws 19F, the circuit board 15 can be reliably prevented from being indirectly flooded.

  In the present embodiment, the extending direction of the groove 23A is inclined with respect to the vertical direction, and a discharge port 23C for discharging the liquid flowing into the groove 23A is provided at the lower end of the groove 23A. Because it is a feature, it can be drained reliably.

  In the present embodiment, the rubber key 17 is provided with a boss portion 17H that fits into the hole 15B provided in the circuit board 15 to position the rubber key 17 with respect to the circuit board 15 and covers the hole 15B. It is characterized by having.

  As a result, while positioning the rubber key 17 with respect to the circuit board 15, even if the operation panel 13 is wet and water accumulates in the rubber key 17, the circuit board 15 is indirectly wetted. Can be reliably prevented.

4). Correspondence between Invention Specific Items and Embodiment In this embodiment, the rubber key 17 corresponds to the elastic key described in the claims, and the first skirt portion 17C corresponds to the skirt portion described in the claims. The first cover 19 corresponds to the cover member described in the claims, the second skirt portion 19E corresponds to the cover skirt portion described in the claims, and the support claw 19F corresponds to the claims. This corresponds to the support protrusion described in (1).

(Second Embodiment)
The boss portion 17H according to the above-described embodiment has a cup shape with a recess, but in the present embodiment, the boss portion 17H has a solid round bar shape as shown in FIG.

(Third embodiment)
In the above-described embodiment, the plate portion 17A has a simple flat plate shape. However, in the present embodiment, as shown in FIG. 8, a drain water channel 17J is provided between the adjacent operation projections 17B in the plate portion 17A. In addition, the plate 17A is inclined so that the base of the operation projection 17B is higher than the water channel 17J.

  And the water channel 17J for drainage between the adjacent operation projection parts 17B includes a water channel 17J extending in the width direction and a water channel 17J extending in a direction crossing the width direction, and any of the water channels 17J finally flows into Is guided to the first skirt portion 17C side. Therefore, it is possible to reliably prevent the circuit board 15 from being indirectly covered with water.

(Other embodiments)
In the above-described embodiment, the groove 23A is provided in the base member 23, but the present invention is not limited to this. For example, the groove 23A may be formed integrally with the rubber key 17.

  In the above-described embodiment, the groove 23A extends in the left-right direction so that the left end side is lower than the right end side. However, the present invention is not limited to this, and for example, the extension direction end ( It is good also as a structure which becomes low, so that it approaches the center part of an extension direction, and becomes low, so that it approaches a left end and a right end.

  In the above-described embodiment, the groove portion 23A is set so that the front side is lower than the rear side, but the present invention is not limited to this, for example, the configuration in which the rear side is lower than the front side, or It is good also as a structure without an elevation difference in the front-back direction.

Moreover, in the above-mentioned embodiment, although the 2nd skirt part 19E was provided, you may abolish this.
Further, in the above-described embodiment, the concave portion 17F that is depressed in the protruding direction of the support claw 19F is provided in the first skirt portion 17C so as to cover the support claw 19F, but the present invention is not limited to this, and the concave portion It is good also as a shape which avoided the support nail | claw 19F, without providing 17F.

  In the above-described embodiment, since the circuit board 15 and the like are disposed in an inclined state, the first skirt portion 17C and the groove portion 23A are provided only on the lower end portion 15A side, but the present invention is not limited to this. Instead, the first skirt portion 17C, the groove portion 23A, and the like may be provided on the entire circumference corresponding to the outer edge portion of the circuit board 15.

  Further, the present invention is not limited to the above-described embodiment as long as it matches the gist of the invention described in the claims.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 3 ... Image forming part, 5 ... Image reading part, 7 ... Ejection port, 9 ... Operation key,
13 ... Operation panel, 15 ... Circuit board, 15A ... Lower end, 15B ... Hole,
17 ... Rubber key, 17A ... Plate part, 17B ... Operation projection part,
17C ... 1st skirt part, 17D ... Pressing protrusion part, 17E ... Recessed part, 17F ... Recessed part,
17H ... Boss part, 17J ... Water channel, 19 ... First cover, 19A ... Through hole,
19B ... 1st holding hook, 19C ... 2nd holding hook, 19D ... 1st cover main body,
19E ... 2nd skirt part, 19F ... Supporting claw, 19H ... Locking part, 19J ... Projection part,
21 ... second cover, 23 ... base member, 23A ... groove, 23C ... discharge port,
23D: Supporting part.

Claims (8)

A circuit board on which an electric circuit is formed;
An elastic key disposed so as to cover the upper side of the circuit board and elastically deforming in response to an operation force from a user;
A portion of the elastic key corresponding to the outer edge portion of the circuit board is provided with a skirt portion extending downward from the circuit board so as to cover the outer edge portion.
Further, a waterproof structure for an operation panel, characterized in that a groove portion extending along the lower end of the skirt portion is provided on the lower side of the skirt portion. A base member made of a material harder than the elastic key is disposed on the lower side of the circuit board,
The waterproof structure for an operation panel according to claim 1, wherein the groove is provided in the base member.   3. The waterproof structure for an operation panel according to claim 1, wherein an upper end of the groove portion is set to be higher than a lower end of the skirt portion. The elastic key includes a plate portion substantially parallel to the circuit board, and an operation protrusion that protrudes upward from the plate portion and receives the operation force,
A cover member that covers the plate portion and that is provided with a through hole through which the operation projection portion passes,
The waterproof structure for an operation panel according to any one of claims 1 to 3, wherein the cover member is provided with a cover skirt portion extending downward toward the groove portion. The cover member and the cover skirt portion are integrally formed of a material harder than the elastic key,
The cover member is provided with a support protrusion that protrudes from the cover skirt portion side to the lower surface side of the circuit board to support the circuit board,
The waterproof structure for an operation panel according to claim 4, wherein the skirt portion is formed with a recess that is recessed in the protruding direction of the support protrusion so as to cover the support protrusion. The circuit board is disposed in an inclined state with respect to the vertical direction,
The waterproof structure for an operation panel according to claim 1, wherein the groove is provided at least on a lower end side of the circuit board. The extending direction of the groove is inclined with respect to the vertical direction,
The waterproof structure for an operation panel according to any one of claims 1 to 6, wherein a discharge port for discharging the liquid flowing into the groove is provided at a lower end of the groove.   The elastic key is provided with a boss portion that fits into a hole provided in the circuit board to position the elastic key with respect to the circuit board and covers the hole. The image forming apparatus according to claim 1.

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