Waterproof mechanism of the measuring device

Abstract

Provided is a waterproofing mechanism for waterproofing a mass sensor of a weighing device without using a diaphragm or a special jig. A waterproofing mechanism (20) for a weighing device is characterized by comprising: a weighing pan (11); a mass sensor (12) to which the load of the weighing pan is transmitted; a device case (10) that accommodates the mass sensor; a pan boss (14) that supports and holds the weighing pan above the device case; and a pan boss surrounding member (13) provided around the pan boss in the circumferential direction and fixed to the device case, wherein the weighing pan has a side wall portion (112) continuously extending downward from the periphery of a pan portion thereof, and when the weighing pan is lowered downward by a specified amount, the side wall portion engages with the pan boss surrounding member in the circumferential direction, and a lower surface (1111) of the pan portion comes into contact with an upper surface (1321) of the pan boss surrounding member.

Description

Technical Field

[0001] This invention relates to a waterproof mechanism for a weighing device.

Background Art

[0002] A scale, which is a weighing device, has a mass sensor inside the device case of the scale, and transmits the load applied to the weighing pan to the mass sensor for weighing. To waterproof around the weighing pan and prevent water from entering the mass sensor, the following means are known. (1) Seal the connection part between the weighing pan and the mass sensor to always prevent water ingress. (2) Seal the connection part between the weighing pan and the mass sensor only during cleaning of the scale.

[0003] Regarding the above (1), as in Patent Document 1, covering the connection part with a diaphragm is well known. Regarding the above (2), covering the connection part with a dedicated rubber cap is well known. Or, there is also Patent Document 2 which has a structure capable of supplying air pressure to the connection part and seals the space between the weighing pan and the mass sensor by introducing air during cleaning.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The constant waterproof mechanism using a diaphragm has a problem that the width (size) of the device is required by the diameter of the diaphragm. Further, although the diaphragm is good during cleaning, during weighing, for example, in the case of a scale with a minimum display of 0.1 mg or less, there is a problem that variations occur due to pressure fluctuations of the diaphragm and the weighed value is not stable. The waterproof mechanism using a rubber cap or the waterproof mechanism using air pressure requires rubber caps and pneumatic jigs that are only necessary during cleaning, and there are problems such as loss of these jigs and inconvenience in management.

[0006] The present invention has been made to solve the above problems, and an object thereof is to provide a waterproof mechanism for waterproofing a mass sensor of a weighing device without using a diaphragm or a dedicated jig.

Means for Solving the Problems

[0007] In order to solve the above problems, a waterproof mechanism for a weighing device according to an aspect of the present invention includes a weighing pan, a mass sensor to which the load of the weighing pan is transmitted, a device case that houses the mass sensor, a pan boss that supports the weighing pan above the device case, and a pan boss peripheral member that is provided in the circumferential direction of the pan boss and is fixed to the device case. The weighing pan includes a side wall portion that is continuously provided downward from the peripheral edge of the pan portion. When the weighing pan is lowered downward by a specified amount, the side wall portion is engaged with the pan boss peripheral member in the circumferential direction, and the lower surface of the pan portion and the upper surface of the pan boss peripheral member are in contact with each other.

[0008] In the above aspect, it is also preferable that waterproof materials are arranged in the circumferential direction on the upper surface of the pan boss peripheral member and on the contact surface that contacts the device case of the pan boss peripheral member, respectively.

[0009] In the above aspect, the inner side surface of the side wall portion and the outer side surface of the pan boss peripheral member are provided with screw portions that engage with each other, and it is also preferable that the side wall portion and the pan boss peripheral member are engaged by rotating the weighing pan in the screw direction.

[0010] In the above aspect, the lower end of the inner side surface of the side wall portion and the outer side surface of the member around the dish boss are provided with an engaging portion that engages with each other in a concave-convex manner, and it is also preferable that the side wall portion and the member around the dish boss engage with each other by means of the concave and convex.

[0011] In the above aspect, the outer side surface of the member around the dish boss includes a first outer side surface that guides the downward movement of the side wall portion, and a second outer side surface that is below the first outer side surface and has a larger diameter than the first outer side surface. The step between the first outer side surface and the second outer side surface restricts the downward movement of the side wall portion, and it is also preferable to prevent excessive squeezing of the waterproof material.

[0012] In the above aspect, when an overload is applied to the weighing dish, it is also preferable to prevent the lower end of the side wall portion from interfering with the outer side surface of the member around the dish boss and transmitting the overload to the mass sensor.

[0013] In the above aspect, it is also preferable that the waterproof mechanism for the weighing device includes an elastic body that biases the dish boss in a direction away from the dish receiver between the dish boss and the dish receiver of the dish boss, and the elastic body is combined with an overload prevention mechanism that separates the dish boss from the dish receiver to release the load.

[0014] In the above aspect, when the weighing dish is lowered by the specified amount and the engagement is made, it is also preferable that the weighing dish is fixed to the member around the dish boss, and the member around the dish boss becomes a stopper for the weighing dish during device transportation.

Effect of the Invention

[0015] According to the present invention, it is possible to provide a waterproof mechanism for waterproofing the mass sensor of a weighing device without using a diaphragm or a dedicated jig.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

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Embodiments for Carrying Out the Invention

[0017] Next, preferred embodiments of the present invention will be described with reference to the drawings. In the following description of the embodiments, the same components are denoted by the same reference numerals, and duplicate descriptions are omitted.

[0018] 1. First Embodiment FIG. 1 is a diagram showing a "weighing device" equipped with a waterproof mechanism for a weighing device according to the first embodiment, which is (a) a plan view of the weighing device, (b) a left side view of the weighing device, and (c) a longitudinal sectional view of the weighing device (sectional view c-c shown in b).

[0019] Reference numeral 1 denotes a weighing device, and the weighing device 1 is an electronic scale (hereinafter referred to as scale 1). The scale 1 includes a device case 10, a weighing pan 11, a mass sensor 12, and a member around the dish boss 13.

[0020] The device case 10 is formed of aluminum die-casting, zinc die-casting, or stainless steel. The device case 10 has a split structure of an upper case 10u and a lower case 10d, and the upper case 10u and the lower case 10d are fitted with each other via a sealing material such as packing. A waterproof connector 15 is fixed to the upper case 10u, and a power cable, an RS232C cable, etc. are attached thereto.

[0021] The mass sensor 12 is housed in the device case 10. The mass sensor 12 includes a Roberval mechanism 121 and a sensor body 122. The Roberval mechanism 121 is a structure for transmitting the load received by the weighing pan 11 to the sensor body 122. It is formed of a rectangular metal block and includes a floating portion that receives the load from the weighing pan 11, a fixed portion that is fixed to the device case 10, upper and lower auxiliary rods that connect the floating portion and the fixed portion, and a load transmission portion that transmits the load acting on the floating portion to the sensor body 122, which is a known one. The sensor body 122 shows an electromagnetic balance type sensor as an example in this embodiment, but is not limited thereto, and may be, for example, a strain gauge type or a capacitance type sensor.

[0022] As shown in Fig. 1(c), the weighing pan 11 is supported downward by the Roberval mechanism 121 via an upwardly convex dish boss 14 and is disposed above the device case 10. A dish receiver 16 having a recess formed therein for receiving the lower end portion of the dish boss 14 is fixed to the floating portion of the Roberval mechanism 121.

[0023] An elastic body 17 that biases the dish boss 14 in a direction away from the dish receiver 16 is disposed between the dish boss 14 and the dish receiver 16. The dish boss 14 is biased by the elastic body 17 and is disposed in a state of being locked by a dish boss retainer 18 disposed on the upper surface of the dish receiver 16. When an overload is applied to the weighing pan 11, the dish boss 14 sinks downward, and the dish boss 14 and the dish receiver 16 are separated by the elastic body 17, so that the overload is not transmitted to the mass sensor 12. These dish boss 14, elastic body 17, dish receiver 16, and dish boss retainer 18 are known overload prevention mechanisms. The details thereof shall be cited from Japanese Patent No. 6414864.

[0024] Next, the "waterproof mechanism" of this embodiment will be described. FIG. 2 is a perspective view of the waterproof mechanism for a weighing device according to the first embodiment, FIG. 3 is an exploded perspective view of the waterproof mechanism for the weighing device, FIG. 4 is a perspective view of the weighing pan of the waterproof mechanism for the weighing device, FIG. 5 is a perspective view of the member around the dish boss of the waterproof mechanism for the weighing device, and FIG. 6 is a longitudinal sectional view after assembly of the waterproof mechanism for the weighing device.

[0025] As shown in FIG. 2, the waterproof mechanism 20 for a weighing device (hereinafter referred to as the "waterproof mechanism") mainly includes a weighing pan 11, a member around the dish boss 13, a dish boss 14, a dish boss retainer 18, and a dish receiver 16.

[0026] As shown in FIG. 3, the weighing pan 11 is fixed to the dish boss 14 by a screw 101. The member around the dish boss 13 is fixed under the upper case 10u by a nut 102. The dish boss 14 contains an elastic body 17, is locked by the dish boss retainer 18 and a screw 103, and is disposed on the dish receiver 16.

[0027] As shown in FIG. 4, the weighing pan 11 is generally a bottomed cylindrical shape as a whole, and includes a dish portion 111 having a flat plane and a side wall portion 112 continuously provided downward from the periphery of the dish portion 111. A screw hole for the screw 101 is formed at the center of the dish portion 111, and a plurality of screw holes for attaching, for example, a tare to the dish portion 111 are formed around it. On the inner side surface 1121 (see FIG. 6) of the side wall portion 112, a female screw portion that engages with the male screw portion of the member around the dish boss 13 is formed in the circumferential direction (not shown). This female screw portion is the "screw portion" in the claims. The weighing pan 11 is preferably formed of a metal such as stainless steel.

[0028] As shown in FIG. 5, the member around the dish boss 13 is generally cylindrical as a whole and has a hollow portion 131. The dish boss 14 is inserted into the hollow portion 131. The member around the dish boss 13 includes, from above, a first waterproof portion 132, a dish guide portion 133, a second waterproof portion 134, and a fixing portion 135 around the hollow portion 131. The member around the dish boss 13, that is, the hollow portion 131, the first waterproof portion 132, the dish guide portion 133, the second waterproof portion 134, and the fixing portion 135 are preferably integrally formed of a metal such as stainless steel.

[0029] The first waterproof part 132 is a cylindrical part at the upper end of the member 13 around the dish boss. On the upper surface 1321 (see FIG. 6) of the first waterproof part 132, a recess (hereinafter referred to as "waterproof recess") 1322 is formed in the circumferential direction, and a ring-shaped packing is arranged in the waterproof recess 1322 as the waterproof material 104. The diameter of the first waterproof part 132 is set to a size such that the measuring dish 11 (the side wall part 112 thereof) does not contact the member 13 around the dish boss during weighing.

[0030] The dish guide part 133 is formed below the first waterproof part 132 and is a cylindrical part having a larger diameter than the first waterproof part 132. The outer diameter of the dish guide part 133 is set to a size that generally matches the inner diameter of the side wall part 112 of the measuring dish 11. On the side surface 1331 (hereinafter referred to as "the first outer side surface". The first outer side surface 1331 is the "outer side surface" in the claims) of the dish guide part 133, a male screw part that engages with the female screw part of the side wall part 112 is formed in the circumferential direction (not shown). This male screw part is the "screw part" in the claims.

[0031] The second waterproof part 134 is formed below the dish guide part 133 and is a cylindrical part having a larger diameter than the dish guide part 133. The side surface of the second waterproof part 134 is hereinafter referred to as the "second outer side surface" 1341 (the second outer side surface 1341 is the "outer side surface" in the claims). On the lower surface 1342 (see FIG. 6) of the second waterproof part 134, a recess 1343 (see FIG. 6, hereinafter referred to as "waterproof recess") is formed in the circumferential direction, and a ring-shaped packing is arranged in the waterproof recess 1343 as the waterproof material 105 in a state of being appropriately crushed.

[0032] The fixing part 135 is the lower end part of the member 13 around the dish boss, is formed below the second waterproof part 134, and is a cylindrical part having a smaller diameter than the second waterproof part 134. The fixing part 135 is inserted through the mounting hole of the device case 10 and fixed by the nut 102.

[0033] When the waterproof mechanism 20 is assembled, in the member 13 around the dish boss, the fixing portion 135 is on the inner side of the device case 10, and the second waterproof portion 134, the dish guide portion 133, and the first waterproof portion 132 are on the outer side of the device case 10. The lower surface 1342 of the second waterproof portion 134 contacts the upper surface of the device case 10 (hereinafter, the lower surface 1342 is referred to as the "contact surface"). The dish boss 14 is disposed in the hollow portion 131, and the second waterproof portion 134, the dish guide portion 133, and the first waterproof portion 132 are disposed around the dish boss 14. The weighing dish 11 is supported by the dish boss 14 and is disposed above the device case 10.

[0034] Above and below the member 13 around the dish boss, waterproof materials 104 and 105 provided in the waterproof recesses 1322 and 1343 are disposed respectively. Note that the waterproof materials 104 and 105 may be sealing materials such as gaskets, waterproof filters, or viscoelastic materials instead of ring-shaped packings. Note that the waterproof material 105 may be a water-resistant adhesive.

[0035] Here, FIG. 6 also shows the state of the waterproof mechanism 20 during weighing. During weighing (normal), the weighing dish 11 is disposed at a position where it does not contact the member 13 around the dish boss. On the other hand, FIG. 7 is a longitudinal sectional view of the waterproof mechanism 20 when an overload is applied during weighing. When an overload is applied to the weighing dish 11, the weighing dish 11 sinks downward, and the inner side surface 1121 of the side wall portion 112 of the dish interferes with the first outer side surface 1331 of the dish guide portion 133 of the member 13 around the dish boss. In particular, since the inner side surface 1121 and the first outer side surface 1331 have thread portions, the threads of each other interfere, and the sinking of the weighing dish 11 is blocked above the dish guide portion 133. That is, the overload from the weighing dish 11 is transmitted to the member 13 around the dish boss and the device case 10, and is difficult to be transmitted to the mass sensor 12 inside the case.

[0036] Next, FIG. 8 is a longitudinal sectional view of the waterproof mechanism 20 during waterproofing. When waterproofing the scale 1, the weighing dish 11 is rotated in the horizontal direction, and the female thread portion of the side wall portion 112 is screwed into the male thread portion of the dish guide portion 133 of the member 13 around the dish boss, and the weighing dish 11 is lowered downward by a specified amount.

[0037] When the measuring dish 11 is lowered by a specified amount, the side wall portion 112 closely adheres to the member around the dish boss 13 in the circumferential direction, and the lower surface 1111 of the dish portion 111 of the measuring dish 11 contacts the upper surface 1321 of the member around the dish boss 13 in a state where the waterproof material 104 is appropriately crushed.

[0038] The specified amount is preferably set with a buffer of at least twice to three times the amount of sinking of the measuring dish 11 during overload. For example, assuming that the amount of sinking of the measuring dish 11 during overload (Figure 7) is about 1 mm, the amount of sinking of the measuring dish 11 during waterproofing (Figure 8) is set to 2 mm. By setting it to be at least twice, it is possible to prevent the waterproof mechanism 20 from entering the waterproof state during overload. Also, by setting it to be three times or less, the amount by which the member around the dish boss 13 protrudes from the device case 10 is limited, making it compact and less likely to be affected by lateral impact.

[0039] Here, since the second waterproof portion 134 of the member around the dish boss 13 is set to have a larger diameter than the dish guide portion 133, a step 136 is provided between the first outer side surface 1331 and the second outer side surface 1341. When the measuring dish 11 is lowered beyond the specified amount, the upper surface of the second waterproof portion 134 interferes with the lower end portion of the side wall portion 112, restricting the further lowering of the dish and preventing excessive crushing of the waterproof material 104 disposed on the upper surface 1321 of the member around the dish boss 13.

[0040] As described above, according to the waterproof mechanism 20 of the present embodiment, when the measuring dish 11 is lowered downward by a specified amount, the measuring dish 11 directly engages with the component (member around the dish boss 13) of the device case 10. Then, the upper and lower waterproof portions (the first waterproof portion 132 and the second waterproof portion 134) formed on the member around the dish boss 13 provide circumferential waterproofing, preventing water from entering the inside of the device case 10 (the mass sensor 12).

[0041] The above waterproofing is achieved simply by rotating the weighing pan 11 horizontally (tightening the screw). Therefore, no special jig is required to put the scale in a waterproof state. Also, the weighing pan 11 and the member around the pan boss 13 are made of metal, and no diaphragm that would cause instability in the measured value is used. Since the waterproof mechanism 20 does not use a diaphragm, the width of the device can be reduced, which is suitable for built-in scales on the production line.

[0042] Also, according to the waterproof mechanism 20 of this embodiment, the waterproof material 104 that is easily worn by contact with the vertically moving weighing pan 11 can be replaced by the user without relying on a vendor by making the waterproof recess 1322 have an upward opening. Also, by providing a step 136 on the member around the pan boss 13, excessive crushing of the waterproof material 104 is prevented, so that the waterproofing of the first waterproof portion 132 functions properly.

[0043] Also, the waterproof mechanism 20 of this embodiment is configured to share and combine components with a known overload prevention mechanism composed of the pan boss 14, the pan receiver 16, the elastic body 17, and the pan boss retainer 18. Furthermore, since the waterproof mechanism 20 of this embodiment has a configuration that causes interference between the member around the pan boss 13 and the weighing pan 11, the overload prevention function is enhanced in this regard as well.

[0044] Also, the waterproof mechanism 20 of this embodiment also functions as a stopper during transportation. FIG. 8 also shows the state of the waterproof mechanism 20 when the scale 1 is being transported. During transportation, in a general scale, since the weighing pan is a movable part, it is removed from the device case and packaged separately from the device case. Also, the device case is packaged in a state where the connecting part (such as the pan boss) with the weighing pan is strictly protected. In contrast, for the scale 1 of this embodiment, in the state of FIG. 8, the member around the pan boss 13 becomes a stopper for the weighing pan 11, and the side wall portion 112 of the weighing pan 11 functions like a protective cap for the connecting part (pan boss 14). Therefore, there is no need to package the weighing pan 11 separately, nor is it necessary to package the device case 10 strictly.

[0045] 2. Second Embodiment FIG. 9 is a longitudinal sectional view of the waterproof mechanism for a weighing device according to the second embodiment. In the waterproof mechanism 20 of the first embodiment, the weighing pan 11 and the member around the pan boss are screw-engaged, but in the waterproof mechanism 20 of the second embodiment, the weighing pan 11 and the member around the pan boss are configured to be engaged with each other by unevenness (hook engagement).

[0046] Instead of the female screw portion, the weighing pan 11 is provided with a convex portion 1122 (hereinafter referred to as "engaging convex portion") in the circumferential direction at the lower end of the inner side surface 1121 of the side wall portion 112. In this embodiment, the weighing pan 11 is preferably formed of, for example, metal or synthetic resin and has appropriate elasticity. The member around the pan boss 13 is provided with a concave portion 1332 (hereinafter referred to as "engaging concave portion") in the circumferential direction at a position below the upper surface 1321 by a specified amount on the first outer side surface 1331 of the pan guide portion 133. These engaging convex portion 1122 and engaging concave portion 1332 are the "engaging portions" in the claims. Note that the shape of the engaging portion is not limited to that shown in the figure, and various modifications are possible.

[0047] The state of the waterproof mechanism 20 of this embodiment during weighing (normal) is the same as that of the first embodiment (FIG. 6). When an overload is applied to the weighing pan 11, the engaging convex portion 1122 formed at the lower end of the side wall portion 112 interferes with the first outer side surface 1131 of the pan guide portion 133 of the member around the pan boss 13, and the sinking of the weighing pan 11 is blocked by the frictional resistance generated by the engaging convex portion 1122.

[0048] Then, during waterproofing (FIG. 9), when the weighing pan 11 is strongly lowered, the interference between the engaging convex portion 1122 and the first outer side surface 1131 is released by the elasticity of the pan, and the side wall portion 112 is guided by the pan guide portion 133 and descends. When the weighing pan 11 descends to the specified amount, the engaging convex portion 1122 of the weighing pan 11 is hook-engaged with the engaging concave portion 1332 of the member around the pan boss 13, and the lower surface 1111 of the pan portion 111 of the weighing pan 11 contacts the upper surface 1321 of the member around the pan boss 13 in a state where the waterproof material 104 is appropriately crushed.

[0049] As described above, even with the waterproof mechanism 20 of this embodiment, when the weighing pan 11 is lowered by a specified amount, the weighing pan 11 directly engages with a component (member around the pan boss 13) of the device case 10. Then, the upper and lower waterproof portions (first waterproof portion 132 and second waterproof portion 134) formed on the member around the pan boss 13 provide circumferential waterproofing, preventing water from entering the mass sensor 12.

[0050] The above waterproofing is achieved simply by engaging the weighing pan 11 in a concave-convex manner. Therefore, no dedicated jig is required to make the scale waterproof. Also, no diaphragm is used in the waterproof mechanism 20 of this embodiment.

[0051] Even in this embodiment, the upper waterproof material 104 can be easily replaced, and due to the step 136 between the first outer side surface 1331 and the second outer side surface 1341, the waterproofing of the first waterproof portion 132 functions properly.

[0052] This embodiment is also configured to be combined with a known overload prevention mechanism and has a configuration that creates interference between the member around the pan boss 13 and the weighing pan 11. In this regard, the overload prevention function is enhanced.

[0053] In this embodiment as well, the member around the pan boss 13 serves as a stopper for the weighing pan 11, and the side wall portion 112 of the weighing pan 11 functions like a protective cap for the connecting portion (pan boss 14). Therefore, during transportation, there is no need to separately package the weighing pan 11, nor is it necessary to carefully package the device case 10.

[0054] 3. Modification Example 1 In the above embodiments, the waterproof mechanism 20 includes the elastic body 17 so as to be combined with a known overload prevention mechanism. However, as a waterproof mechanism, the elastic body 17 is an optional element. FIG. 10 is a longitudinal sectional view of a waterproof mechanism for a weighing device according to Modification Example 1 of the embodiments, showing the case where Modification Example 1 is applied to the first embodiment. When the waterproof mechanism 20 is not combined with a known overload prevention mechanism, the pan boss 14 may be directly fixed to the floating frame side of the mass sensor 12 (roboval mechanism 121). The same applies to the second embodiment.

[0055] 4. Modification Example 2 In the first embodiment, as the "threaded portion", the weighing dish 11 side has an internal thread portion and the peripheral member 13 of the dish boss has an external thread portion. However, a configuration in which the weighing dish 11 side has an external thread portion and the peripheral member 13 of the dish boss has an internal thread portion may also be used (not shown). Even in this form, the same effect as that of the first embodiment can be obtained.

[0056] 5. Modification Example 3 In the second embodiment, as the "engagement portion", the weighing dish 11 side has an engagement convex portion 1122 and the peripheral member 13 of the dish boss has an engagement concave portion 1332. However, a configuration in which the weighing dish 11 side has an engagement concave portion and the peripheral member 13 of the dish boss has an engagement convex portion may also be used (not shown). In this case, when an overload is applied to the weighing dish 11 during weighing, the interference is reduced. However, as a waterproof mechanism, the same effect as that of the second embodiment can be obtained.

[0057] As described above, preferred embodiments and modification examples of the overload waterproof mechanism of the present invention have been described. However, these are merely examples of the present invention, and each embodiment and each modification can be combined based on the knowledge of those skilled in the art, and such forms are also included in the scope of the present invention.

Explanation of Reference Numerals

[0058] 1 Scale (weighing device) 10 Device case 11 Weighing dish 111 Dish portion 1111 Lower surface of the dish portion 112 Side wall portion 1121 Inner side surface 1122 Engagement convex portion (engagement portion) 12 Mass sensor 13 Peripheral member of the dish boss 131 Hollow portion 132 First waterproof portion 1321 Upper surface of the peripheral member of the dish boss 133 Dish guide portion 1331 First outer side surface 1332 Engagement concave portion (engagement portion) 134 Second waterproof portion 1341 Second outer side surface 1342 Contact surface 135 Fixing part 136 Stage 14 Dish boss 16 Dish receiver 17 Elastic body 18 Dish boss retainer 20 Waterproof mechanism for metering device 104, 105 Waterproof material

Claims

1. A weighing dish, a mass sensor to which the load of the weighing dish is transmitted, a device case for housing the mass sensor, a dish boss for supporting the weighing dish above the device case, a member around the dish boss provided in the circumferential direction of the dish boss and fixed to the device case, and comprising: The weighing dish includes a side wall portion continuously provided downward from the peripheral edge of the dish portion, When the weighing dish is lowered downward by a specified amount, the side wall portion engages with the member around the dish boss over the circumferential direction, and the lower surface of the dish portion contacts the upper surface of the member around the dish boss A waterproof mechanism for a weighing device, characterized in that.

2. On the upper surface of the member around the dish boss and on the contact surface that contacts the device case of the member around the dish boss, waterproof materials are respectively arranged in the circumferential direction The waterproof mechanism for a weighing device according to claim 1, characterized in that.

3. The inner side surface of the side wall portion and the outer side surface of the member around the dish boss are provided with screw portions that engage with each other, and the side wall portion and the member around the dish boss engage by turning the weighing dish in the screw direction The waterproof mechanism for a weighing device according to claim 1, characterized in that.

4. The lower end portion of the inner side surface of the side wall portion and the outer side surface of the member around the dish boss are provided with engaging portions that engage with each other in a concave-convex manner, and the side wall portion and the member around the dish boss engage by the concave-convex The waterproof mechanism for a weighing device according to claim 1, characterized in that.

5. The outer side surface of the member around the dish boss includes a first outer side surface for guiding the lowering of the side wall portion, and a second outer side surface that is below the first outer side surface and has a larger diameter than the first outer side surface. The step between the first outer side surface and the second outer side surface restricts the lowering of the side wall portion and prevents excessive crushing of the waterproof material The waterproof mechanism for a weighing device according to claim 2, characterized in that.

6. When an overload is applied to the weighing dish, the lower end portion of the side wall portion interferes with the outer side surface of the member around the dish boss, preventing the overload from being transmitted to the mass sensor The waterproof mechanism for a weighing device according to claim 3 or 4, characterized in that.

7. The waterproof mechanism for a weighing device includes an elastic body that biases the dish boss in a direction away from the dish receiver between the dish boss and the dish receiver of the dish boss, and is combined with an overload prevention mechanism that separates the dish boss from the dish receiver by the elastic body to release the load The waterproof mechanism for a weighing device according to any one of claims 1 to 6, characterized in that.

8. When the measuring dish is lowered by the specified amount and the engagement is made, the measuring dish is fixed to the member around the dish boss, and the member around the dish boss serves as a stopper for the measuring dish during device transportation. The waterproof mechanism for a weighing device according to any one of claims 1 to 7, characterized in that.

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