JP2007107989A - Waterproof balance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a balance having high waterproofness while reducing manufacturing costs. <P>SOLUTION: The waterproof balance comprises at least a measuring dish; a load sensor; a pan stop rod; a cover member having an opening for allowing a movable section to penetrate; a base member; a battery lid; a movable section packing for waterproofing the opening; a body section packing for waterproofing the fit section between the cover member and the base member; and a battery storage section packing for waterproofing the area between the base member and the battery lid. The waterproof balance also comprises a press member for pressure-bonding the movable section packing to the cover member; a cap pressure-bonded to the pan stop rod; and a plurality of projections for pressure-bonding the body section packing over the entire periphery of the fit section of both the members to at least one of the cover member and the base member. The entry path of water, or the like to the inside from the outside of the casing is blocked by pressure-bonding each packing, thus achieving high waterproofness having a high pressure waterproof level. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a scale having a waterproof mechanism.

  In the conventional waterproof structure, a concave groove is provided in the divided casing A and a pressing rib is provided in the divided casing B over the entire circumference of the fitting portion between the divided casings A and B. A waterproof structure that presses and fits the divided casings A and B by pressing the rubber annular packing inserted in is pressed with a pressing rib is disclosed (for example, see Patent Document 1).

  Also, a waterproof structure is disclosed in which the packing is crushed and sandwiched between the fitting surface of the rear case and the outer peripheral edge (convex shape) of the front case when the front case and the rear case are fitted (for example, patents) Reference 2).

Furthermore, as a waterproof structure of the movable part of the scale, it relates to a diaphragm (seal) that covers the opening of the upper case (weighing pan mounting part) that prevents the intrusion of disturbance, and a base (outer periphery) that adheres to the upper case opening. ) And a through hole (inner circumference) that is in close contact with the plate bearing is connected by a bellows to be movable, and a structure that prevents disturbance is disclosed. In order to eliminate the accompanying measurement error, a balance is disclosed in which a waterproof and dustproof and breathable member is provided on the upper case (see, for example, Patent Document 3).
Japanese Patent Laid-Open No. 10-4273 JP 2004-333871 A JP 2005-140626 A

  However, in Patent Document 1 and Patent Document 2, the packing is crushed by a protrusion (pressing pressure rib, outer peripheral edge (convex shape)) to achieve waterproofing. In the case of high pressure waterproofing, only the force to press the packing is increased by tightening the screws that fix the housing to be engaged. Along with this, the housing itself must be strong enough to withstand the tightening of screws, which may lead to an increase in cost.

  In Patent Document 3, the upright portion of the through hole 8a of the diaphragm 8 is fitted and fixed in the annular concave groove 7d of the plate bearing 7 in a close contact state, but the through hole 8a is raised in the annular concave groove 7d. Since it is not fixed by a member that presses the portion, even if it is effective as drip-proof or dust-proof, when standing up to high-pressure waterproofing, the raised portion of the annular groove 7d and the through hole 8a is caused by water pressure. There is a possibility that a gap or gap will be generated between the two and water may enter from there, and the waterproofness is incomplete.

  Furthermore, in Patent Document 3, the waterproof and dustproof breathable member 31 provided in the upper case 3 may be touched with a finger or may be damaged by hitting an object in a bare state, thereby impairing the function. Therefore, a large protective member such as the cover 4 is required. When the upper case 3 and the cover 4 are integrally formed, for example, when the waterproof and dustproof breathable member 31 is deteriorated, the integrally formed upper case 3 and cover 4 must be replaced, and the use cost is increased. May go up.

Therefore, the present invention solves the above-mentioned problems and provides a balance with high waterproofness and dustproofness while reducing manufacturing costs.

  In order to solve the above problems, the present invention includes a weighing pan, a load sensor that receives a load applied to the weighing pan, a pan receiving rod that transmits a load from the weighing pan to the load sensor, a load sensor, and a pan receiving rod. A cover member having an opening for penetrating the movable portion, a base member that fits into the cover member and forms a housing having the load sensor therein, and a battery for housing and fixing the battery in the base member A lid, a movable portion that waterproofs the opening of the cover member, a main body packing that waterproofs a fitting portion between the cover member and the base member, and a battery housing packing that waterproofs between the base member and the battery lid In at least one of the waterproof balance comprising: a holding member that crimps the movable portion packing to the cover member; a cap that crimps the tray to the tray receiving rod; and at least one of the cover member and the base member. A plurality of protrusions for crimping the main body packing over the entire circumference of the fitting portion of both members, and closing the entry path from the outside to the inside of the housing by crimping each packing. A waterproof scale is provided.

  In addition, the battery lid includes an air pressure adjusting unit including a porous film having waterproofness and dustproofness and a gate part that protects the porous film.

  The movable part packing is formed in a substantially hollow disk shape, and is provided over the entire periphery near the outer peripheral edge of the disk, embedded in the periphery of the opening of the cover member, and around the inner peripheral edge of the disk. An upright portion that covers the plate receiving rod protruding from the opening provided between the embedded portion and the upright portion is connected, and the upright portion that accompanies the movement of the plate receiving rod during loading A bellows part that can be expanded and contracted according to the movement is provided.

  The embedding portion includes a flexible protrusion for filling the gap over the entire circumference of the portion to be embedded.

  The pressing member includes at least one protrusion that presses the cover member around the outer periphery of the movable portion packing including the embedded portion.

  The upright portion is formed by increasing the material pressure in the direction in which a part of the portion pressed between the tray support bar and the cap is pressed over the entire circumference.

  The waterproof scale according to the present invention includes a weighing pan, a load sensor that receives a load applied to the weighing pan, a tray receiving rod that transmits a load from the weighing pan to the load sensor, and a movable part that includes the load sensor and the tray receiving rod. A cover member having an opening to be penetrated, a base member that forms a housing that is fitted to the cover member and includes the load sensor therein, a battery lid for housing and fixing a battery in the base member, and At least a movable part packing for waterproofing the opening of the cover member, a main body packing for waterproofing a fitting part between the cover member and the base member, and a battery housing packing for waterproofing between the base member and the battery cover are provided. In the waterproof balance, at least one of the pressing member for crimping the movable part packing to the cover member, the cap for crimping the tray receiving bar, and the cover member and the base member, both members A plurality of protrusions for crimping the main body packing over the entire circumference of the fitting portion, and by closing each invasion path such as water from the outside to the inside of the housing by crimping each packing Further, it is possible to have a high waterproof property at a high atmospheric pressure waterproof level, and it is possible to use a wider range of materials without limiting the packing material.

In addition, since the battery cover includes a pressure adjusting unit including a waterproof and dustproof porous membrane and a gate portion that protects the porous membrane, measurement at the time of measurement while having high waterproofness It is possible to maintain accuracy. Further, since it is the exchange of the porous membrane by replacing the battery cover but also become readily adaptable to a variety of testing or inspection, to allow a reduction in manufacturing cost.

  The movable part packing is formed in a substantially hollow disk shape, and is provided over the entire periphery near the outer peripheral edge of the disk, embedded in the periphery of the opening of the cover member, and around the inner peripheral edge of the disk. An upright portion that covers the plate receiving rod protruding from the opening provided between the embedded portion and the upright portion is connected, and the upright portion that accompanies the movement of the plate receiving rod during loading A bellows part that can be expanded and contracted in accordance with the movement, and the embedding part comprises a flexible protrusion part for filling a gap over the entire circumference of the embedded part, and the pressing member is The movable portion packing including the embedded portion includes at least one protrusion that presses the vicinity of the outer peripheral edge of the movable portion packing against the cover member, and the upright portion is sandwiched between the dish receiving rod and the cap. A part of the part to be pressed is moved in the direction to be pressed over the entire circumference. Since the pressure is increased, the cover opening including the movable part can be completely sealed, and the movable part packing does not generate a gap or a gap with respect to the contact member, so that it is high even in waterproofing under high atmospheric pressure. It is possible to have waterproofness.

  The waterproof scale according to the present invention includes a weighing pan, a load sensor that receives a load applied to the weighing pan, a tray receiving rod that transmits a load from the weighing pan to the load sensor, and a movable part that includes the load sensor and the tray receiving rod. A cover member having an opening to be penetrated, a base member that forms a housing that is fitted to the cover member and includes the load sensor therein, a battery lid for housing and fixing a battery in the base member, and At least a movable part packing for waterproofing the opening of the cover member, a main body packing for waterproofing a fitting part between the cover member and the base member, and a battery housing packing for waterproofing between the base member and the battery cover are provided. In the waterproof balance, at least one of the pressing member for crimping the movable part packing to the cover member, the cap for crimping the tray receiving bar, and the cover member and the base member, both members Over the entire fitting portion periphery comprises a plurality of protrusions of crimping the body portion packing, the route of entry from the outside to the inside of the housing, is intended to close to crimp the respective packing.

  In addition, the battery lid includes an air pressure adjusting unit including a porous film having waterproofness and dustproofness and a gate part that protects the porous film.

  The movable part packing is formed in a substantially hollow disk shape, and is provided over the entire periphery near the outer peripheral edge of the disk, embedded in the periphery of the opening of the cover member, and around the inner peripheral edge of the disk. An upright portion that covers the plate receiving rod protruding from the opening provided between the embedded portion and the upright portion is connected, and the upright portion that accompanies the movement of the plate receiving rod during loading A bellows part that can be expanded and contracted according to the movement is provided.

  The embedding portion includes a flexible protrusion for filling the gap over the entire circumference of the portion to be embedded.

  The pressing member includes at least one protrusion that presses the vicinity of the outer peripheral edge of the movable portion packing including the embedded portion against the cover member over the entire periphery.

  The upright portion is formed by increasing the material pressure in the direction in which a part of the portion pressed between the tray support bar and the cap is pressed over the entire circumference.

  An outline of components of the waterproof balance X according to the embodiment of the present invention will be described with reference to FIGS. 1 to 4. 1 is an external perspective view of the waterproof balance of the present embodiment, FIG. 2 is an exploded perspective view of FIG. 1, and FIG. 3 is an external top view of the waterproof balance X with the weighing pan 1 removed. FIG. 4 is a cross-sectional view taken along line AA of FIG.

  According to this, the waterproof balance X is generally composed of the weighing pan 1, the cover member 7, the main body packing 12 and the base member 13, and the weighing pan 1 is received inside the balance surrounded by the cover member 7 and the base member 13. And a load sensor assembly 10 having a dish receiving rod 10a movable by a load and a load sensor.

  The load cover member 7 has an opening for projecting the dish receiving rod 10a on the upper surface of the cover member 7. The opening uses a movable part packing 6, a pressing plate 3, a screw 4 and a cap 5 that are adapted to the movement of the dish receiving rod 10a for waterproofing the opening. It is hermetically sealed by pressure bonding between members.

  In addition, a part of the bottom surface of the base member 13 includes a well-known battery housing portion 13d (not shown). The battery housing portion packing 14 for waterproofing the battery housing portion 13d and the battery housing portion packing 14 are provided. The battery cover 15 is formed so as to be pressed and pressed against the base member 13. Further, although not shown here, the battery cover 15 is provided with an atmospheric pressure adjusting mechanism section for maintaining a balance between the internal and external atmospheric pressures at a predetermined position.

  Thereby, the inside of the waterproof balance X will be described later with respect to the waterproof structure of the C part, the D part and the E part shown in the AA cross-sectional view of FIG. 4, but is completely sealed except for the atmospheric pressure adjusting mechanism of the E part. .

  Then, the waterproof structure of each part is explained in full detail using a drawing. First, the waterproof structure of the cover member 7 and the base member 13 using the main body packing 12 will be described with reference to FIG. FIG. 5A is a cross-sectional view showing the state of the waterproof structure before mating shown as part C in FIG. 4, and FIG. 5B is a diagram showing the state of the waterproof structure after mating. is there.

  As shown in FIGS. 5 (a) and 5 (b), the outer peripheries of the cover member 7 and the base member 13 are provided with fitting portions that fit together over the entire circumference, and the fitting of both the members 7 and 13 is performed. The main body packing 12 is sandwiched between the joints and pressed.

  The fitting portion of the cover member 7 includes a step having an outer peripheral edge as a convex step portion 7a and an inner peripheral edge as a concave step portion 7b, and the fitting portion of the base member 13 has an inner peripheral edge as a convex step portion 13a. In the present embodiment, each of the concave step portion 7b of the cover member 7 and the convex step portion 13a of the base member 13 is provided with a step facing the outer peripheral edge. The projections 7c and 13c that are convex in the direction are provided over the entire circumference, and the projections 7c and 13c are not in a straight line in the direction in which the cover member 7 and the base member 13 are fitted, and the projections of the opposing members The main body packing 12 is pressed against each surface of the step and the concave step, and the main body packing 12 is further crushed locally to bring the packing 12 into close contact with the members 7 and 13.

  This provides higher adhesion than the fitting of the cover member 7 of the type without the projections 7c and 13c and the base member 13 by only the concave steps 13a and the convex steps 7b. That is, when there is variation in the flatness of each surface of the convex step portion and the concave step portion of each member sandwiching the main body portion packing 12 and the pressing force pressing the main body portion packing 12 is not uniform, the pressing force In particular, when the cover member 7 and the base member 13 are resin molded products as in the present embodiment, water may invade from the weak parts, but the main body extends over the entire circumference. By providing the protrusions 7c and 13c so as to be further embedded in the part packing 12, the influence of the variation in the degree of flatness can be supplementarily reduced. Along with this, in the design of the member, it is only necessary to make the size of the projections that can allow variation in dimensional accuracy, leading to cost reduction.

  Further, the tips of the protrusions 7c and 13c are not provided in a straight line in the vertical direction, and the pressing force from the protrusions acts not only in the vertical direction but also presses the main body packing 12 against each protrusion: t By disposing only by being shifted, the pressure-bonding force is further increased between the protrusions 7c and 13c, so that high waterproofness is achieved.

  In addition, since the pressing force is locally increased by providing the protruding portion having a small pressing area, for example, when pressing is performed on the surface, a gap may be generated between the members 7 and 13 and the packing material. It can also be used for packing of hard materials.

  Further, when the cover member 7 and the base member 13 are fitted, the gap between the protruding step portion 7a and the protruding step portion 13a is formed to be narrower than the thickness of the main body packing 12 sandwiched between the protruding step portion 7a. 12 is pressed not only in the fitting direction of the cover member 7 and the base member 13 described above but also in the direction in which the cover member 7 and the base member 13 are pressed against each other. Even if the screw to be loosened may be loosened, the sealing property of both the members 7 and 13 is not lost, and the waterproof property is maintained.

  Next, the waterproof structure of the opening portion of the cover member 7 using the movable portion packing 6 will be described with reference to FIGS. 6 is a cross-sectional view showing a state of the waterproof structure of the opening shown as D part in FIG. 4, FIG. 7 is an enlarged view of F part of FIG. 6, and FIG. 8 is G part of FIG. It is an enlarged view.

  The movable portion packing 6 indicated by the hatched portion in FIG. 6 has a substantially hollow disk shape, and includes an embedded portion 6a embedded in the cover member 7 over the entire circumference near the outer periphery of the disk, An upright portion 6b is provided so as to surround the circumference along the shape of the dish receiving rod 10a protruding above the cover opening surface, and an annular bellows portion is provided between the embedded portion 6a and the upright portion 6b. 6c is comprised.

  As shown in FIG. 7, the cover member 7 includes an annular groove 7 d for press-fitting the embedded portion 6 a of the movable portion packing 6. The embedded portion 6a includes a flexible protrusion 6d over the entire side surface. When the embedded portion 6a is press-fitted into the annular groove 7d, the protrusion 6d is crushed by the inner wall of the annular groove 7d and is crimped. By doing so, it is waterproof.

  Further, the presser plate 3 has a substantially hollow disk shape, and a screw 2 is attached to the cover member 7 in a state in which the vicinity of the outer periphery of the movable portion packing 6 including the embedded portion 6a press-fitted into the annular groove 7d is pressed from above. This is a member fixed by screwing. At this time, at least one protrusion 3a is provided over the entire circumference of the contact surface of the pressing plate 3 that presses the outer peripheral upper surface of the movable portion packing 6 except for the portion above the embedded portion 7d. The cover 6 and the movable part packing 6 are pressure-bonded by further pressing the vicinity of the outer periphery of the packing 6 locally. Moreover, in the load sensor assembly 10 provided with the sensor which detects the load of a balance, the saucer receiving bar 10a comprises the substantially cylindrical shape of a lower surface closing, and screws 4 in the hollow part.

  Further, the cap 5 is placed so as to cover the upright portion 6b from above the upright portion 6b of the movable portion packing 6 that covers a portion of the plate receiving rod 10a, and between the cap 5 and the plate receiving rod 10a. And is formed in a substantially cylindrical shape sandwiching the upright portion 6b, and the screw 4 is inserted from above the hollow portion of the cap 5 and screwed into the hollow portion of the dish receiving rod to be tightened. Thereby, the movable part packing 6 sandwiched between the cap 5 and the dish receiving bar 10a including the upright part 6b is crushed and pressure-bonded between the cap 5 and the dish receiving bar 10a.

  At this time, as shown in FIG. 8, the inner peripheral edge of the raised portion 6b to be crimped is formed in an O-ring shape having a thick material over the entire periphery, and the cap 5 and the dish receiving rod 10a are By being further crushed and pressure-bonded, the gap between the cap 5 and the dish receiving rod 10a is further sealed, and the cover opening is completely sealed.

  Here, the operation of the movable portion of the balance during loading will be described. When an object to be weighed is placed on the weighing pan 1, the tray receiving bar 10 a is pushed down, and the load is transmitted to the load sensor assembly 10. At this time, the upright portion 6b is also pushed down together with the dish receiving rod 10a, and the bellows portion 6c is deformed correspondingly, thereby moving while maintaining a sealed state.

  Subsequently, the atmospheric pressure adjusting mechanism including the surrounding waterproof structure will be described in detail with reference to FIGS. 9 and 10. FIG. 9A is a perspective view showing attachment of the porous film of the atmospheric pressure adjusting mechanism to the battery lid 15, and FIG. 9B is a view of the battery lid 15 as viewed from the bottom.

  This atmospheric pressure adjusting mechanism has a waterproof structure as described above, so that the inside of the balance is hermetically sealed. It is provided to prevent the difference from occurring.

  The battery lid 15 has an air pressure adjusting unit 20 near the center, and the air pressure adjusting unit 20 is provided with a porous film 20a having a waterproof property and a dustproof property, and does not interfere with the air pressure adjusting function of the porous film. A cross-shaped gate portion 20 b having a certain gap is provided on the outer surface of the battery lid 15.

  Further, the base member 13 includes a battery housing portion 13d including a battery housing portion packing 14 that can be waterproofed with the battery lid 15 attached. By attaching the battery lid 15, the battery housing portion packing is provided. 14 is provided with a waterproof structure for crimping 14 to the battery housing portion 13d.

  When the atmospheric pressure adjusting mechanism is provided on the upper surface or side surface (for example, the upper surface of the cover member 7) close to the weighing pan 1 due to the structure of the scale, powder falls or liquid dripping on the atmospheric pressure adjusting mechanism portion. No matter how much waterproofing and dustproofing it is, the pressure adjustment cannot be performed well if the gate portion 15a is blocked.

  Therefore, in order to provide a structure in which the atmospheric pressure adjustment unit 20 is provided on the back surface of the base member 13, the atmospheric pressure adjustment unit 20 is provided on the battery lid 15 attached to the bottom surface of the base member 13. Here, the vicinity of the outer edge of the bottom surface of the base member 13 is preferably provided in the vicinity of the center of the bottom surface of the base member 13 because of the influence of dirt due to dripping of the object to be measured.

  Further, by providing the gate portion 20b, the porous film 20a is prevented from being easily touched in a normal use state in order to prevent the porous film 20a from being damaged or detached, and the liquid material adheres to the porous film 20a. In some cases, there may be a gap that can be cleaned with a cotton swab or the like.

  Further, by reducing the size of the porous membrane 20a, the atmospheric pressure adjusting unit 20? In order to reduce the size of the device itself and prevent further contamination, the minimum area effective for the atmospheric pressure adjustment function is calculated. For example, when the diameter of the outer periphery of the bellows portion 6c that is movable by the load is 30 mm and the sinking amount (vertical movable distance) by the load is 0.1 mm at the maximum, the internal volume change amount is “0.07065CC”. . It is necessary to remove this internal volume change amount within the measurement time. When the measurement time is 0.1 second and the air flow rate of the porous membrane 20a to be used is 5 CC / 100 square millimeters per second, an area of “14.13 square millimeters” or more is sufficient. Thereby, the maximum effect can be exhibited with the minimum necessary pressure adjusting unit 20 (the lowest cost of the porous membrane).

  Further, since the atmospheric pressure adjusting unit 20 is provided in the battery lid 15, even when a problem occurs in the attachment of the porous membrane 20a, it is only necessary to replace the battery lid 15, and it is possible to cope with only the minimum components. In addition, equipment costs can be reduced because it can be used even for models with different external designs.

  Furthermore, various tests or inspections can be easily handled. For example, if a test for confirming complete sealing of a product is to be performed, it can be easily performed by using a battery cover with the gate portion 20b closed. In addition, since the confirmation test of the welded state and the ventilation state of the porous membrane 20a can be performed by the battery lid 15 provided with the atmospheric pressure adjusting unit 20, the scale of the apparatus required for the inspection can be reduced and the production cost can be reduced. it can.

It is an external appearance perspective view of the waterproof balance of a present Example. It is a disassembled perspective view of the waterproof balance of a present Example. It is an external appearance top view. It is AA sectional drawing of FIG. (A) It is sectional drawing before the fitting of the C section of FIG. (B) It is sectional drawing after the fitting of the C section of FIG. It is the D section enlarged view of FIG. It is the F section enlarged view of FIG. It is the G section enlarged view of FIG. (A) It is a battery cover perspective view. (B) It is a battery lid bottom front view. It is the E section enlarged view of FIG.

Explanation of symbols

X waterproof scale 1 weighing pan 2 screw 3 holding plate 3a protrusion 4 screw 5 cap 6 movable part packing 6a embedded part 6b upright part 6c bellows part 6d flexible protrusion part 7 cover member
7a Convex step part 7b Concave step part 7c Protrusion part 7d Annular groove 8 Name plate 9 Screw 10 Load sensor assembly 10a Dish receiving bar 11 Electronic board assembly 12 Main body part packing 13 Base member 13a Convex step part 13b Concave step part 13c Protrusion part 13d Battery Housing part 14 Battery housing part packing 15 Battery cover 16 Yuria screw 17 Rubber leg 18 Screw 19 Dry battery 20 Air pressure adjusting part 20a Porous membrane 20b Gate part

Claims (6)

A weighing pan, a load sensor that receives a load applied to the weighing pan, a tray receiving rod that transmits a load from the weighing pan to the load sensor, and an opening that penetrates a movable portion including the load sensor and the tray receiving rod. A cover member, a base member that fits into the cover member and forms a casing having the load sensor therein, a battery lid for housing and fixing the battery in the base member, and an opening of the cover member are waterproofed In a waterproof balance comprising at least a movable portion packing, a body portion packing that waterproofs a fitting portion between the cover member and the base member, and a battery housing portion packing that waterproofs between the base member and the battery lid,
A holding member that crimps the movable part packing to the cover member, a cap that crimps the dish receiving rod,
Among the cover member and the base member, at least one is provided with a plurality of protrusions that press-fit the main body packing over the entire circumference of the fitting portion of both members,
A waterproof scale characterized in that an intrusion path from the outside to the inside of the casing is closed by crimping each packing.   The waterproof scale according to claim 1, wherein the battery cover includes a pressure adjusting unit including a waterproof and dust-proof porous membrane and a gate portion for protecting the porous membrane.   The movable part packing is formed in a substantially hollow disk shape, and is provided over the entire periphery near the outer peripheral edge of the disk, embedded in the periphery of the opening of the cover member, and around the inner peripheral edge of the disk. An upright portion that covers the plate receiving rod protruding from the opening provided between the embedded portion and the upright portion is connected, and the upright portion that accompanies the movement of the plate receiving rod during loading The waterproof scale according to claim 1 or 2, further comprising a bellows part that can be expanded and contracted in accordance with movement.   4. The waterproof balance according to claim 3, wherein the embedded portion includes a flexible protrusion for filling the gap over the entire circumference of the embedded portion.   The waterproof balance according to claim 3, wherein the pressing member includes at least one protrusion that presses the cover member around the outer periphery of the movable portion packing including the embedded portion.   The upright portion is formed by thickening a material pressure in a direction in which a part of a portion sandwiched between a tray support bar and a cap is pressed over the entire circumference. Item 4. The waterproof balance according to Item 3.

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