JP5080344B2 - Waterproof scale and weighing block used therefor - Google Patents

Description

  The present invention relates to a balance having a waterproof function and a measurement block incorporated therein, and in particular, realizes a waterproof balance capable of high-precision measurement.

Conventionally, a scale having a waterproof function has been widely used in the field of handling foods and marine products, and has been used in such a manner that a hose is used to remove dirt from a weighing dish after use.
In recent years, the need for high-precision weighing has increased even in production and distribution sites where work is carried out in a very harsh environment for scales where water or dust falls on the equipment or the moisture is filled. Therefore, the emergence of a waterproof electronic balance that meets this demand is demanded.
For example, as shown in FIG. 10, a conventional waterproof balance has a diaphragm 9 disposed between an opening of a housing 1 of a balance and a load transmission rod 4 through which a load of a weighing pan 3 is transmitted, thereby reducing the measurement space to the outside world. The load transmission rod 4 is configured to be able to be displaced up and down according to the load placed on the weighing pan 3 (Patent Document 1 below).
JP 2005-283328 A

However, in the structure of a conventional waterproof balance that connects the load transmission rod and the housing with a diaphragm, the force applied to the housing in the case of high-precision weighing causes displacement of the load transmission rod through the diaphragm. Measurement is difficult.
Moreover, the conventional waterproof balance has few configurations that can be commonly used in each type of balance, and lacks versatility.

  The present invention was devised in view of such circumstances, and provides a waterproof balance capable of high-precision weighing, and an object of the invention is to provide a versatile weighing block for use in this waterproof balance. Yes.

The present invention provides a waterproof scale, unitized metered blocks are arranged inside of the balance of the housing, a fixed portion having a mounting portion for mounting to the housing, at Roberval mechanism to the fixing unit An inner edge is supported by a load receiving portion that is displaced by receiving a load on the weighing pan, a sensor portion that detects the displacement of the load receiving portion, and a load support member of the load receiving portion that transmits the load on the weighing pan. An annular member having an annular shape that is fixed to the fixing portion and holds an outer edge of the diaphragm, and the annular member has an outer edge of the diaphragm at an inner portion of the annular ring. A diaphragm holding portion for holding the housing, and a housing coupling portion fixed to a periphery of an opening provided on an upper surface of the housing at an outer portion of the annular ring, and the housing on the annular member. The periphery of the opening is the diaphragm A gap is provided between the diaphragm holding portion and the housing coupling portion so as not to contact the diaphragm, and a peripheral edge of the opening of the housing is formed in the housing coupling portion of the annular member of the measuring block Is characterized in that it is airtightly fixed via a packing .
This unitized weighing block has a diaphragm that guarantees displacement due to the load of the load support member and prevents moisture and dust from entering the periphery of the load support member. If it arrange | positions and airtightly connects between the opening of a housing | casing and the annular member of a measurement block, the waterproof structure of a balance will be completed. In this scale, since the casing and the diaphragm are separated, the force applied to the casing does not affect the displacement of the load support member.

Further, the present invention provides a unitized metered blocks arranged inside the balance housing, a fixed portion having a mounting portion for mounting to the housing, is supported by a Roberval mechanism to the fixing unit The inner edge is held by the load receiving portion that receives and displaces the load on the weighing pan, the sensor portion that detects the displacement of the load receiving portion, and the load support member of the load receiving portion that transmits the load on the weighing pan. And an annular member having an annular shape that is fixed to the fixing portion and holds the outer edge of the diaphragm, and the annular member holds the outer edge of the diaphragm at an inner portion of the annular ring. A diaphragm holding portion, and a housing coupling portion fixed to a peripheral edge of an opening provided on an upper surface of the housing at an outer portion of the ring, and the opening of the housing on the annular member. Perimeter is the diaphragm So as not to contact, it is characterized in that a gap is provided between the diaphragm holder and the casing joint.
This weighing block has a diaphragm that guarantees load transmission by the load bearing member and prevents the ingress of moisture from the periphery of the load bearing member. The waterproof structure is completed simply by airtightly connecting the opening of the housing and the annular member.

In the measuring block according to the present invention, the load support member can be fixed to the load receiving portion with an inner edge of the diaphragm interposed therebetween.
By carrying out like this, the inner edge of a diaphragm can be kept airtight in the load support member of a load receiving part.

In the measuring block of the present invention, a packing, an outer edge of the diaphragm, and an annular holding plate are sequentially stacked on the diaphragm holding portion of the annular member, and the holding plate and the annular member are stacked. The outer edge of the diaphragm and the packing are fixed, and the periphery of the opening of the casing and the annular member are fixed via the packing on the casing coupling portion of the annular member. Can be configured.
By doing so, the opening of the housing and the measuring block can be hermetically coupled without affecting the diaphragm.

The waterproof balance of the present invention can measure with high accuracy because the force applied to the housing does not affect the measurement.
In addition, the weighing block of the present invention has versatility, and can be adjusted without attaching the housing, and the adjusted weighing block can be used in each type of waterproof scale.

Embodiments of the present invention will be described with reference to the drawings.
1 is a perspective view of a waterproof balance according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of the waterproof balance, FIG. 3 is a cross-sectional view of the waterproof balance in FIG. FIG. 5 is a sectional view of the waterproof balance of FIG. 1 in the BB direction, FIG. 6 is a partially enlarged view of this sectional view, and FIG. 7 is an embodiment of the present invention. FIG. 8 is an exploded perspective view of the main part of the measuring block, and FIG. 9 is a diagram showing a diaphragm mounting structure of the measuring block.

As shown in FIGS. 1 and 2, the waterproof balance includes a weighing dish 10 on which an object to be weighed is placed, a dish receiving plate 11 that supports the weighing dish 10, an upper housing provided with a display window 123 and an opening 122. 121, a circuit board 19 on which the electronic display board 18 and necessary electronic circuits are mounted, a battery box 17, and a lower casing 124 to which the unitized measuring block 40 is fixed. A support leg 20 whose height can be adjusted is provided on the back side of the lower housing 124.
When the upper housing 121 is air-tightly fitted to the lower housing 124, there is no passage of moisture or dust inside the housings 121 and 124 other than the opening 122. And this opening 122 is also sealed by the structure mentioned later.

As shown in FIGS. 7 and 8, the weighing block 40 is connected to a fixed portion 41 having a mounting hole 45 for mounting to the lower housing 124, and connected to the fixed portion 41 through parallel links 42 and 43 of a Roverval mechanism. The load receiving portion 44 that receives the load on the weighing pan 10 and is displaced in the vertical direction, and is attached to the mounting hole 412 of the fixing portion 41 and the mounting hole 441 of the load receiving portion 44 to detect the displacement of the load receiving portion 44. Tuning fork sensor 50 (see FIGS. 3 and 4).
The fixed portion 41 and the load receiving portion 44 are formed into a block shape by a die casting method using an aluminum alloy as a material so as to maintain high rigidity against twisting. In addition, “stolen meat (recessed parts)” for weight reduction are provided in various places.

Leaf springs 421 and 431 are coupled to the parallel links 42 and 43, respectively, and the leaf springs 421 and 431 are fixed to the fixing portion 41 and the load receiving portion 44, respectively. The leaf spring 421 coupled to the upper parallel link 42 is fixed to the fixing position 413 of the fixing portion 41 and is fixed to the mounting hole 443 of the load receiving portion 44. The leaf spring 431 of the lower parallel link 43 is fixed to the fixing portion 41 and the load receiving portion 44 so that the parallel link 42 and the parallel link 43 are parallel to each other (FIGS. 5 and 6).
The fixing position 413 of the fixing portion 41 to which the parallel link 42 is fixed is configured to be slightly displaced by the rotation of the rotating member 414, and the rotating error is adjusted by rotating the rotating member 414.

As shown in FIGS. 2 and 7, the measuring block 40 further includes an annular member 46 whose legs are fixed to the fixing portion 41 with screws 33, and a packing 47 arranged on the annular member 46. And a diaphragm 48 whose inner edge is held by the load support member 442 of the load receiving portion 44, and an annular holding plate 49 for fixing the outer edge of the diaphragm 48.
As shown in FIGS. 4, 6, and 9 (a), the load support member 442 is a bolt-shaped member, and the tray receiving plate 11 is fixed to the upper portion with screws 30. The lower portion of the load bearing member 442 is fitted into a hole of the load receiving portion 44 and is fixed by a screw 34 (FIG. 9A) that enters from the lateral direction toward the hole.

The diaphragm 48 is formed of silicon rubber, has a thick annular body at the inner edge and the outer edge, and is connected by a thin wall that undulates concentrically therebetween. As shown in FIG. 9A, the inner edge of the diaphragm 48 is sandwiched between the load support member 442 and the load receiving portion 44 and fixed to the load receiving portion 44.
Further, as shown in FIG. 9B, the outer edge of the diaphragm 48 is fixed to a portion inside the annular member 46 (this portion is referred to as a “diaphragm holding portion”). A packing 47 is disposed on the annular member 46, and the outer edge of the diaphragm 48 is disposed on the packing 47, and a pressing plate 49 is further stacked thereon, and the pressing plate 49 and the annular member 46 are connected to each other. By tightening with the screw 32, the outer edge of the diaphragm 48 is fixed to the diaphragm holding portion of the annular member 46.

Further, as shown in FIG. 9C, the periphery of the opening 122 of the upper housing 121 is fixed to the outer portion of the annular member 46 (this portion will be referred to as “housing coupling portion”). Is done. The periphery of the opening 122 of the upper housing 121 is disposed at the housing coupling portion of the annular member 46 via the packing 47 and is fixed to the annular member 46 by the screw 31.
At this time, a gap is formed between the upper casing 121 and the periphery of the opening 122 so as not to contact the diaphragm 48 on the annular member 46.

Thus, the space between the load receiving portion 44 and the annular member 46 is closed with the diaphragm 48, and the periphery of the opening 122 of the upper housing 121 and the annular member 46 are hermetically coupled to each other. Intrusion of moisture and dust from the opening 122 of the housing 121 is completely prevented.
Further, since the diaphragm 48 is not connected to the upper casing 121, the load receiving portion 44 coupled to the diaphragm 48 transmits the load on the weighing pan 10 without being affected by the force applied to the casing. Therefore, accurate measurement is possible.

Further, the measuring block 40 in the form of FIG. 7 has a diaphragm 48 that ensures the transmission of the load by the load support member 442 and the load receiving portion 44 and prevents the intrusion of moisture from the periphery of the load support member 442. Therefore, even when incorporated in the housing of any type of scale, a waterproof structure can be realized simply by airtightly coupling the opening of the housing and the annular member 46.
Therefore, it is possible to produce and adjust the weighing block 40 in the form of FIG. 7 as an independent product, and to manufacture a waterproof balance of each model using this weighing block 40.
Note that the structure, material, and method of joining the members shown here are all examples, and the present invention is not limited thereto.
Here, the load is detected using a tuning fork sensor, but the present invention can also be applied when other load sensors are used.

  The waterproof balance of the present invention can measure with high accuracy even in a harsh environment in which water or dust is bathed or moisture is filled. This waterproof scale can be used in a wide range of fields such as food processing and marine product manufacturing sites, chemical and pharmaceutical manufacturing sites, electronic parts and other chemical processing sites, and building sites.

The perspective view of the waterproof balance which concerns on embodiment of this invention 1 is an exploded perspective view of the waterproof balance of FIG. Sectional view in the AA direction of the waterproof balance of FIG. Partial enlarged view of the cross-sectional view of FIG. BB sectional view of the waterproof balance of FIG. Partial enlarged view of the cross-sectional view of FIG. The perspective view of the measurement block which concerns on embodiment of this invention 7 is an exploded perspective view of the main part of the measuring block of FIG. The figure which shows the diaphragm attachment structure of the measurement block of FIG. Figure showing a conventional waterproof scale

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Weighing pan 11 Plate receiving plate 17 Battery box 18 Electronic display board 19 Circuit board 20 Support leg 30 Screw 31 Screw 32 Screw 33 Screw 34 Screw 40 Weighing block 41 Fixed part 42 Parallel link 43 Parallel link 44 Load receiving part 45 Mounting hole 46 Annular member 47 Packing 48 Diaphragm 49 Holding plate 50 Tuning fork sensor 121 Upper housing 122 Opening 123 Display window 124 Lower housing 412 Tuning fork sensor mounting hole 413 Plate spring fixing position 414 Rotating member 421 Plate spring 431 Plate spring 441 Tuning fork sensor mounting hole 442 Load bearing member 443 Mounting hole

Claims (4)

A unitized weighing block placed inside the housing of the scale,
A fixed portion having a mounting portion for mounting to the housing,
A load receiving portion that is supported by a robust mechanism on the fixed portion and receives a load on the weighing pan and is displaced;
A sensor unit for detecting displacement of the load receiving unit;
A diaphragm in which an inner edge is held by a load support member of the load receiving portion to which a load on the weighing pan is transmitted;
An annular member having an annular shape, which is fixed to the fixing portion and holds an outer edge of the diaphragm;
With
The annular member has a diaphragm holding portion that holds an outer edge of the diaphragm in an inner portion of the ring, and is fixed to a peripheral edge of an opening provided on an upper surface of the casing in an outer portion of the ring. A gap is provided between the diaphragm holding portion and the casing coupling portion so that a peripheral edge of the opening of the casing does not contact the diaphragm on the annular member.
A waterproof balance , wherein a peripheral edge of an opening of the housing is hermetically fixed to the housing coupling portion of the annular member of the measuring block via a packing . A unitized weighing block placed inside the housing of the scale,
A fixed portion having a mounting portion for mounting to the housing,
A load receiving portion that is supported by a robust mechanism on the fixed portion and receives a load on the weighing pan and is displaced;
A sensor unit for detecting displacement of the load receiving unit;
A diaphragm in which an inner edge is held by a load support member of the load receiving portion to which a load on the weighing pan is transmitted;
An annular member having an annular shape, which is fixed to the fixing portion and holds an outer edge of the diaphragm;
With
A casing in which the annular member has a diaphragm holding portion that holds an outer edge of the diaphragm in an inner portion of the ring, and is fixed to a peripheral edge of an opening provided on an upper surface of the casing in an outer portion of the ring A gap is provided between the diaphragm holding portion and the casing coupling portion so that a peripheral edge of the opening of the casing does not contact the diaphragm on the annular member. Feature weighing block. 3. The measuring block according to claim 2 , wherein the load support member is fixed to the load receiving portion with an inner edge of the diaphragm interposed therebetween. A metering block of claim 2 or 3, on the diaphragm holder of the annular member, the packing, the outer edge and an annular retainer plate of the diaphragm are sequentially laminated, wherein the holding plate and the circle An annular member is fixed with an outer edge of the diaphragm and a packing interposed therebetween, and a peripheral edge of the opening of the casing and the annular member are fixed via a packing on the casing coupling portion of the annular member. A weighing block characterized by being made.