JP3901272B2 - Water flow switch device and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water flow switch device used in a water heater, a bath with a water heater, and the like, and more particularly, to a water flow switch device that operates a hot water supply device by detecting a water flow in a water passage using a reed switch, and a manufacturing method thereof.
[0002]
[Prior art]
In general, a hot water heater in a bath is provided with a water flow detector in its water passage, and a hot water supply device is operated after detecting the water flow. As disclosed in Japanese Utility Model Publication No. 63-35232, such a water flow switch has a flap that swings in response to a water flow. A magnet is fixed to the flap, and the flap swings. When the magnet approaches the reed switch mounted on the casing, the reed switch is connected by receiving the magnetic force (closed state), and when the magnet moves away, the switch is turned off (open state).
[0003]
Such a water flow switch device is configured by assembling a lower case and an upper case, and a swingable flap plate is inserted into the lower case from the upper opening in addition to the inlet and outlet portions of the water flow. A flap chamber is formed. A flap plate having a magnet fixed thereto is swingably attached to the upper case.
[0004]
When manufacturing this water flow switch, place the upper case face down and place it inside up, fix the flap plate shaft inside the upper case, and then turn the upper case over. Then, with the flap plate hanging down with the inside of the upper case facing down, the flap plate is inserted into the upper opening of the lower case, and the lower case and the upper case are assembled. Further, in order to seal between the upper case and the lower case, an O-ring is interposed between the upper opening and the fitting portion of the upper case fitted therein.
[0005]
[Problems to be solved by the invention]
However, when the flap plate attached to the upper case is suspended and inserted into the flap chamber of the lower case, a separate bearing is provided so that the flap plate does not fall, and this is fixed by spot welding, The shaft is held by caulking the tip, or a special screw is separately used to fix the shaft.
[0006]
For this reason, there existed a problem that the number of parts increased, the number of manufacturing processes increased, or the structure became complicated.
[0007]
An object of the present invention is to provide a water flow switch device having a simple configuration, reducing the number of parts, and having a small number of manufacturing steps, and a method for manufacturing the same.
[0008]
[Means for Solving the Problems]
According to the first aspect of the present invention, there is provided a lower case in which a water flow is introduced from the inlet portion into the flap chamber and led out from the outlet portion, and a flap plate that receives the water flow in the lower case and swings with the magnet. A water flow switch device that is assembled so as to sway downwardly so as to be swingable, and includes a shaft on which the flap plate swings around the shaft, an upper case, and a lower case. The lower case has an opening into which the flap plate is inserted into the flap chamber, and an annular ring for press-fitting the O-ring into the upper case corresponding to the periphery of the opening. A groove is formed, the shaft is disposed across the annular groove, and both sides of the shaft are held by an O-ring press-fitted into the groove . According to the first aspect of the present invention, since the flap plate hanging from the upper case is held using the O-ring that seals the upper case and the lower case, the flap plate shaft is separately provided. A member such as a screw to be fixed is not required, and steps such as caulking and welding are not required, so that the number of parts can be reduced and the number of assembly steps can be reduced. That is, when assembling the water flow switch device, it can be assembled to the lower case while the flap plate is suspended inside the upper case.
[0009]
Further, since an annular groove for press-fitting the O-ring is formed in the upper case, the flap plate can be easily attached only by making the dimension of the shaft cross the annular groove.
[0010]
According to a second aspect of the present invention, in the first aspect of the present invention, a plurality of bearings for receiving the axis of the flap plate are formed in the upper case, and the position of the center line of at least one bearing is the center of another bearing. It is characterized by being different from the position of the line. According to the second aspect of the present invention, when the shaft is inserted into each bearing, the center position of each bearing is shifted, so that the shaft is pressed against the bearing and held in the groove of the bearing. Therefore, the flap plate can be easily held in a state where it is suspended from the upper case simply by press-fitting the shaft into the bearing. Further, as in the first aspect of the invention, no member such as a screw is required, and no steps such as caulking or welding are required, so the number of parts can be reduced and the number of assembly steps can be reduced. .
[0011]
According to a third aspect of the present invention, in a state where a flap plate swingably attached to the inside of the upper case via a shaft is suspended, the flap plate is inserted into the flap chamber from the upper opening of the lower case, In the manufacturing method of the water flow switch for sealing the periphery and the annular fitting groove formed in the upper case with an O-ring, the inner side of the upper case is arranged facing upward, and the diameter is larger than the diameter of the annular fitting groove. A long shaft is attached to the flap plate, and the O-ring is press-fitted into the fitting groove of the upper case so as to overlap both ends of the shaft, and then the flap plate hanging down with the inner side of the upper case facing downward After being inserted into the flap chamber from the upper opening of the case, the upper case and the lower case are assembled and fixed. According to the invention described in claim 3 , the manufacturing method using the invention described in claim 1 described above is used, and, similarly to the invention described in claim 1, the axis of the flap plate hanging from the upper case is used. Since it is a configuration that uses an O-ring, the number of parts can be reduced and the number of steps can be reduced, and the upper case and the lower case can be assembled and fixed while the flap plate is suspended, The water flow switch device can be easily assembled.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS. 1 to 6 of the accompanying drawings.
[0013]
The water flow switch 1 according to the present embodiment is provided in a water passage that leads from the bath to the combustor, and detects the water flowing in the water passage and operates the combustor.
[0014]
As shown in FIGS. 1 and 2, the water flow switch 1 includes a lower case (half case) 7 in which an inlet portion 3 into which a water flow is introduced, an outlet portion 5 to be led in and out, and a flap chamber 13 are formed. And an upper case (half case) 9 in which the flap plate 11 is suspended in the flap chamber 13, and the lower case 7 and the upper case 9 are tightened with screws 10a, 10b, 10c, and 10d for assembly. It is fixed together. The flap chamber 13 forms a space in which a flap plate 11 (described later) inserted therein swings.
[0015]
The lower case 7 is provided with flange portions 15 for assembling the upper case 9 on top of each other. As shown in FIG. 5, assembly screws 10a, 10b are provided at the four corners of the flange portion 15. Screw holes 12a, 12b, 12c, and 12d that are screwed into 10c and 10d are formed. A thermistor is inserted into the flap chamber 13 at the bottom of the lower case 7 to detect the temperature of the water flowing through the water passage.
[0016]
The flange portion 15 is formed with a seal piece 19 protruding upward at the periphery of the upper opening 18. When the upper case 9 is assembled to the seal piece 19, an O-ring 21 is pressed to form a seal structure 20. The outer peripheral surface of the seal piece 19 is inclined from the outer side to the inner side from the base end to the front end, and an O-ring 21 is fitted on the outer peripheral surface. The seal piece 19 is configured to press-fit an O-ring 21 between a groove 51 (described later) formed in the upper case 9 described later.
[0017]
As shown in FIG. 2, the upper case 9 is formed with screw holes 25a, 25b, 25c, and 25d through which the assembly screws 10a, 10b, 10c, and 10d are passed, respectively. The screws 10a, 10b, 10c, and 10d are screwed together so as to match the screw holes 12a, 12b, 12c, and 12d.
[0018]
A fitting recess 29 for fitting the reed switch 27 is formed on the upper surface of the upper case 9, so that the reed switch 27 does not protrude from the case. The reed switch 27 mounted here is provided with a glass tube in which a pair of terminals that closes a circuit by contacting with a magnetic force is enclosed in a main body 31, and the glass tube is embedded with a resin. A mounting piece 33 is extended from the main body 31, and screw holes F and F for fixing are formed on the mounting piece 33 because they are commercially available. It is not used in this embodiment. In other words, in the present embodiment, the corners of the mounting piece 33 are pressed and fixed to the upper case 9 by the heads 35 and 37 of the mounting screws 10a and 10b described above. On the other hand, a pair of pedestals 39 and 41 are formed on the bottom surface of the fitting recess 29 at positions close to the screw holes 25 a and 25 b of the upper case 9. The corners of the mounting piece 33 are placed on the pedestals 39 and 41, respectively. That is, as shown in FIG. 3, only a part of the mounting piece 33 is clamped and fixed between the receiving bases 39 and 41 and the screw heads 35 and 37, so that it can be fixed securely and attached to the main body 31. Can prevent damage to the reed switch 27 without applying excessive force. In particular, even when the reed switch 27 is deformed or the like, the deformation can be allowed and can be securely attached without being damaged.
[0019]
As shown in FIG. 5, the flap plate 11 is suspended inside the upper case 9 so as to be swingable about the axis of the shaft 45 . A magnet 43 is fixed to the flap plate 11, and when the flap plate 11 is swung up by a water flow and moves up, the reed switch 27 is approached. As shown in FIG. 4, the upper end portion of the flap plate 11 is supported by a shaft 45, and both end portions of the shaft are placed on bearings 47 a formed on the upper case 9. A bearing 47b for mounting the central portion of the shaft 45 is also formed, and the shaft 45 is pivotally supported at a total of four locations. FIG. 4 shows a state in which the upper case 9 shown in FIG. 5 is turned upside down.
[0020]
The shaft 45 is held by bearings 47 a and 47 b by an O-ring 21, and the O-ring 21 is fitted in the groove 51 of the upper case 9. Therefore, when assembling, as shown in FIG. 4, the shaft 45 is placed on the bearings 47 a and 47 b with the upper case 9 facing upward (lower side), and then the O-ring 21 is press-fitted into the groove 51. The flap plate is not dropped from the upper case 9 even if the flap plate 11 is directed downward by the holding force of the O-ring 21. Further, the upper case 9 is formed with a guide surface 53 for guiding the shaft 45 to the bearings 47a and 47b so that the flap plate 11 is inserted obliquely, and the shaft 45 can be easily disposed on the bearings 47a and 47b when assembled. It has become.
[0021]
Next, with reference to FIG. 6, the seal structure by the O-ring 21 will be described.
[0022]
When the lower case 7 and the upper case 9 are assembled, the O-ring 21 is formed by the inclined outer surface 19a of the seal piece 19 described above, and the peripheral wall 55 and the bottom wall 59 that form the L-shaped cross section of the upper case 9. The configuration is such that the three points S, T, and Y are in pressure contact. Thus, since the O-ring 21 is in pressure contact at the three points S, T, and Y, a reliable seal can be achieved. Moreover, since the inclined outer surface 19a is inclined obliquely with respect to the tightening direction W of the assembly screw 10a, the tightening of the assembly screw 10a increases the tightening of the lower case 7 with respect to the upper case 9. In particular, in the screw holes 25a, 25b, 25c, 25d, 12a, 12b, 12c, and 12d formed in the upper case 9 and the lower case 7, the screw holes are centered (the center is Each screw hole and screw can be manufactured roughly. Furthermore, since the screw hole of the upper case 9 can be enlarged, screwing can be easily performed and workability is good.
[0023]
Next, the assembly method of the water flow switch concerning this Embodiment is demonstrated. First, as shown in FIG. 4, the upper case 9 is attached with the upper surface down and the inner side up, and the flap plate 11 is attached. In this case, the shaft 45 can be easily fitted into the bearings 47a and 47b by inserting the shaft 45 obliquely along the guide surface 53. In this case, since the bearings 47a and 47b are provided on the extended surface of the guide surface 53, if the shaft 45 is slid along the guide surface 53, the shaft 45 can be fitted into the bearings 47a and 47b as it is. And after arrange | positioning the axis | shaft 45 to the bearings 47a and 47b, the O-ring 21 is press-fitted in the groove | channel 51, and it mounts on the axis | shaft 45. FIG. Thereby, since the shaft 45 is supported by the O-ring 21, even if the upper case 9 is turned over and the flap plate 11 is lowered, the flap plate 11 is held by the O-ring 21 and does not fall.
[0024]
That is, as shown in FIG. 5, the flap plate 11 is directed downward, the upper case 9 is covered on the lower case 7, and the O-ring is interposed, so that the flap plate 11 is passed through the upper opening 18 of the lower case 7. Then, it is inserted into the flap chamber 13 from above.
[0025]
Next, as shown in FIG. 2, a reed switch 29 is installed in the fitting recess 29 on the upper surface of the upper case 9, and the assembly screws 10a, 10b, 10c, 10d are inserted into the screw holes 25a, 25b, 25c, 25d. The upper case 9 is fixed to the lower case 7 by being inserted and screwed into the screw holes 12 a, 12 b, 12 c, 12 d of the lower case 7. At this time, since the screw hole can be enlarged by the above-described seal structure by the O-ring 21, the assembling work by screws is easy.
[0026]
At the same time, the reed switch 27 is fixed in such a way that the corners of the mounting pieces are pressed against the pedestals 39 and 41 of the upper case 9 by the heads 35 and 37 of the mounting screws 10a and 10b.
[0027]
On the other hand, when the assembly screws 10a, 10b, 10c, and 10d are tightened, as shown in FIG. 6, the O-ring 21 is disposed on the inclined outer surface 19a of the seal piece 19, and when tightened, the outer surface 19a and the peripheral wall are tightened. 55 and the bottom wall 59 are pressed against each other at three points S, T, and Y to ensure a reliable seal. Further, since the inclined outer surface 19a is inclined with respect to the tightening direction of the assembly screw 10a, the screw hole can be centered as the assembly screw 10a is tightened, and the assembly with the screw is easy. is there.
[0028]
As described above, according to the present embodiment, the flap plate can be easily fixed to the upper case with a simple configuration, and the upper case can be easily fixed to the lower case with the flap plate suspended. And workability is good. Moreover, the number of parts can be reduced and the assembly process can be simplified.
[0029]
Next, a second embodiment of the present invention will be described with reference to FIG. In the description of the second embodiment, the differences from the above-described first embodiment will be described, and in FIG. 7, the same parts as those in the above-described embodiment are denoted by the same reference numerals, Detailed description of the portion is omitted.
[0030]
In the second embodiment, the center line 61 of the pair of bearings 47a and 47a located on the outside is different from the center line 63 of the pair of bearings 47b and 47b located on the inside of the bearings 47a and 47a. Yes. In this way, by shifting the center line of the bearing, the shaft 45 fitted in common with the bearing is pressed against and held by the bearing from both sides on the side surface. Therefore, in this state, even if the upper case 9 is turned upside down and the flap plate 11 is suspended, the flap plate 11 can be held sufficiently and can be mounted on the lower case 7 as it is.
[0031]
In the second embodiment, without using the O-ring 21, the shaft 45 can be easily held only by press-fitting into the bearings 47a and 47b, and the flap plate 11 can be suspended as it is. Easy assembly.
[0032]
The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. For example, in the second embodiment, the position of the center line 63 of the pair of bearings 47a and 47b located on the inside is shifted, but this is not limiting, and the position of the center line 63 of only one bearing 47a is shifted. Even if it exists, the same effect can be acquired.
[0033]
【The invention's effect】
According to the first aspect of the present invention, since the flap plate hanging from the upper case is held using an O-ring that seals the upper case and the lower case, the member for fixing the shaft is provided. This is not required separately, and the number of parts can be reduced and the number of assembly steps can be reduced.
[0034]
Further, the flap plate can be easily attached only by arranging the axis of the flap plate across the O-ring annular groove.
[0035]
According to the invention described in claim 2 , since the shaft can be held only by changing the position of the center line of the bearing that receives the shaft of the flap plate, the number of parts can be reduced and the number of assembly steps can be reduced. it can.
[0036]
According to invention of Claim 3 , it is a manufacturing method using invention of Claim 1 mentioned above, can reduce the number of parts, can reduce assembly man-hours, and is easy to assemble. it can.
[0037]
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a water flow switch device according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing an assembly structure of a reed switch.
FIG. 3 is a plan view of the water flow switch device shown in FIG. 1;
FIG. 4 is an exploded perspective view showing a structure for attaching a flap plate in the upper case.
FIG. 5 is an exploded perspective view showing an assembly structure of an upper case and a lower case.
FIG. 6 is a cross-sectional view showing a seal structure using an O-ring.
FIG. 7 is a plan view showing the inside of an upper case according to a second embodiment of the present invention.
[Explanation of symbols]
1 Water flow switch 7 Lower case 9 Upper case 11 Flap plate 21 O-ring 33 Mounting piece 45 Shaft 47a Bearing 47b Bearing 61 Center line 63 Center line

Claims (3)

A lower case that introduces a water flow into the flap chamber from the inlet portion and leads out from the outlet portion, and a flap plate that swings with the magnet in response to the water flow in the lower case is suspended in the flap chamber so as to be swingable. In the water flow switch device constructed by assembling the attached upper case,
The flap plate includes a shaft that swings around the shaft and an O-ring that seals the upper case and the lower case, and the lower case has an opening through which the flap plate is inserted into the flap chamber. An annular groove for press-fitting an O-ring is formed in a portion of the upper case corresponding to the periphery of the opening, and the shaft is disposed across the annular groove, The water flow switch device is characterized in that the portion is held by an O-ring press-fitted into the groove . The bearing according to claim 1, wherein a plurality of bearings for receiving the axis of the flap plate are formed in the upper case, and the position of the center line of at least one bearing is different from the position of the center line of the other bearing . Water flow switch device. Inserted into the flap chamber from the upper opening of the lower case, with the flap plate swingably attached to the inner side of the upper case via the shaft, annularly formed around the upper opening and the upper case In the manufacturing method of the water flow switch which seals the fitting groove of the O-ring,
The upper case is disposed with the inner side facing up, a shaft longer than the diameter of the annular fitting groove is attached to the flap plate, and the O-ring is fitted to the both ends of the shaft so that the O-ring is overlapped with the fitting groove of the upper case. Next, after inserting the flap plate hanging down with the inner side of the upper case facing down into the flap chamber from the upper opening of the lower case, the upper case and the lower case are assembled and fixed. Manufacturing method of water flow switch.

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