JP6105462B2 - Load cell unit and scale device - Google Patents

Description

  Embodiments described herein relate generally to a load cell unit and a weighing apparatus.

  2. Description of the Related Art Conventionally, a weighing apparatus including a load cell includes a stopper that stops overload so that the load cell does not undergo plastic deformation due to overload. In addition, the scale device generally includes a stopper that prevents the load cell from causing plastic deformation due to an impact when the scale device drops upside down.

  For example, the stopper is disposed so as to limit excessive displacement of the movable portion by facing a target portion of the movable portion that is displaced by the load of the load cell via a gap having a predetermined size. The two types of stoppers described above limit the displacement of the movable part in the opposite direction.

  Such a stopper requires at least an adjustment portion that can adjust the distance to the target portion of the load cell, and a holding portion that holds the adjustment portion and does not move relative to the base portion. Conventionally, since an overload stopper and a reverse drop impact stopper are provided separately, an adjustment portion and a holding portion are required for each. For this reason, the number of parts increases, leading to an increase in the size of the apparatus.

  The problem to be solved by the present invention is to provide a load cell unit and a scale device that can be miniaturized.

The load cell unit according to the embodiment includes a load cell, an upper limit portion, a lower limit portion, a restricted portion, an overload adjustment portion, and an inverted drop impact adjustment portion. The load cell has a fixed portion fixed to the base portion and a movable portion that receives a load to be measured, and is deformed when the load is received. The upper limit portion has a through hole, that are fixedly provided relative to the base. The lower restricting portion is fixedly provided with respect to the base portion, and is arranged below the upper restricting portion with a space therebetween. The restricted portion is fixedly provided with respect to the movable portion, and is positioned between the upper restricting portion and the lower restricting portion, with a predetermined gap between the upper restricting portion and the lower restricting portion. Facing each other. The overload adjusting part is attached to the restricted part so that the distance from the lower restricting part can be changed by adjustment work from above the through hole of the upper restricting part. The upside down impact adjustment unit is provided at a position that does not overlap with the overload adjustment unit in plan view, and the upper limit unit is capable of changing a distance from the limited unit by adjustment work from above the upper limit unit. Is attached.

  Further, the weighing apparatus according to the embodiment calculates the weight of the weighing object based on the load cell unit described above, an upper plate connected to the load cell unit and on which the weighing object is placed, and an output from the load cell unit. A control unit.

FIG. 1 is a perspective view illustrating an appearance of a scale device according to an embodiment. FIG. 2 is a cross-sectional view illustrating a configuration of the scale device of the embodiment. FIG. 3 is a perspective view illustrating an appearance of a frame included in the main body of the embodiment. FIG. 4 is a cross-sectional view showing the configuration of the load cell unit of the embodiment.

  Embodiments will be described with reference to the drawings. FIG. 1 is a perspective view showing an appearance of the scale device 1. FIG. 2 is a cross-sectional view showing the configuration of the scale device 1. As shown in FIG. 1, the scale device 1 includes a main body 2, an upper plate 3, an operation display panel 4, and a customer panel 5. Further, as shown in FIG. 2, the scale device 1 includes a load cell unit 6 and a control unit 7 in a main body 2 having a substantially rectangular parallelepiped box shape.

  The upper plate 3 is a table that is installed substantially horizontally and on which a measurement object is placed. The load applied to the upper plate 3 is transmitted to the load cell 61 provided in the load cell unit 6. The load cell 61 receives a load applied to the upper plate 3 and outputs a signal corresponding to the load. Based on the output, the control unit 7 calculates a load value.

  The operation display panel 4 includes an operation unit 41 and a display unit 42. The operation unit 41 is, for example, a keyboard. The display unit 42 is a liquid crystal panel, for example. The operation display panel 4 accepts an operation by a store clerk through the operation unit 41 and displays various information for the store clerk through the display unit 42.

  The customer panel 5 has an operation unit and a display unit (both not shown). The operation unit is, for example, a keyboard. The display unit is, for example, a liquid crystal panel. The customer panel 5 receives an operation by the customer through the operation unit, and displays various information for the customer through the display unit. The customer panel 5 may be a display-only panel that does not have an operation unit.

  FIG. 3 is a perspective view showing an appearance of the frame 21 provided in the main body 2. The frame 21 is a framework of the main body 2 and is a member serving as a base. The frame 21 includes a frame-shaped base 211, a column 212 standing on the base 211, and a planar top plate 213 fixed on the column 212. The top plate 213 is located immediately below the upper plate 3. The main body 2 is configured by fixing a member such as a side wall 22 (see FIG. 1) to the frame 21.

  FIG. 4 is a cross-sectional view showing the configuration of the load cell unit 6. The load cell unit 6 includes a load cell 61, a restricted portion 62, a lower restriction portion 63, an upper restriction portion 64, an overload adjustment portion 65, and an inverted drop impact adjustment portion 66.

  The load cell 61 is called a beam type, a single point type or the like, has a shape having a hole in the center of a horizontally long block, has a fixed portion 611 on one end side, and a movable portion 612 on the other end side. Furthermore, it has a strain gauge (not shown).

  The fixing portion 611 is fixed to the lower surface of the top plate 213 of the frame 21 by screwing. Here, a reinforcing plate 23 is attached to the top surface of the top plate 213. The reinforcing plate 23 is a rectangular sheet metal, and reinforces the top plate 213 from the upper surface. The fixing portion 611 is screwed with the screw 24 inserted from the upper surface side of the reinforcing plate 23.

  The movable part 612 is a part that receives a load applied to the upper plate 3. The strain gauge is attached to a portion that deforms according to the load of the load cell 61, and the resistance value changes when the strain gauge is deformed. The load cell 61 outputs a signal corresponding to a change in the resistance value of the strain gauge.

  The restricted portion 62 is a member that is fixed to the movable portion 612, that is, a member that is fixed in position, and is, for example, a sheet metal fixed to the upper surface of the movable portion 612. The restricted portion 62 protrudes from the end of the movable portion 612 in plan view. More specifically, the restricted portion 62 protrudes from the movable portion 612 in a direction away from the fixed portion 611. Further, the restricted portion 62 extends substantially horizontally from the end of the movable portion 612.

  The lower restriction portion 63 is fixedly provided with respect to the frame 21 (base portion) and faces the lower surface of the restricted portion 62 via a predetermined gap. More specifically, the lower limit portion 63 is one end portion of the bent sheet metal 67. The bent sheet metal 67 is subjected to a process called Z-bending (or step bending). The other end of the bent sheet metal 67 is fixed to the lower surface of the frame 21.

  The upper restricting portion 64 is a portion facing the upper surface of the restricted portion 62 of the frame 21. That is, it is fixedly provided with respect to the frame 21 (base portion) and faces the upper surface of the restricted portion 62 via a predetermined gap.

  As described above, the lower restricting portion 63 and the upper restricting portion 64 are both fixedly provided to the frame 21 and close to each other, in other words, are integrated. The restricted portion 62 is positioned between the upper restricting portion 64 and the lower restricting portion 63 that are arranged with a space therebetween, and each of the upper restricting portion 64 and the lower restricting portion 63 has a predetermined length. Opposing through a gap of dimensions.

  The overload adjusting part 65 is attached to the restricted part 62 so that the distance from the lower restricting part 63 can be changed. More specifically, the overload adjusting unit 65 is, for example, a male screw and is screwed with a female screw formed in the restricted portion 62. A hole 64a is formed at a position corresponding to the upper limit portion 64 of the frame 21 and the reinforcing plate 23 so that the upper end portion of the screw that is the overload adjusting portion 65 can be exposed.

  The inverted drop impact adjusting unit 66 is attached to the upper limiting unit 64 so that the distance from the limited unit 62 can be changed. More specifically, the inverted drop impact adjusting unit 66 is, for example, a male screw, and is screwed with a female screw formed in the upper restriction unit 64.

  The upper plate 3 is indirectly connected to the movable portion 612. Between the movable portion 612 and the upper plate 3, a block 31, a plate receiving frame 32, and a plate receiving rubber 33 are arranged.

The block 31 is fixed to the upper surface of the movable portion 612 with screws. Further, the block 31 interferes with the hole 21a formed in the frame 21 as shown in FIG. 3, and limits the lateral movement range of the movable portion 612.
The hole 21a and the hole 64a are continuous.

  The dish receiving frame 32 is fixed on the block 31 so as to be kept substantially horizontal. The upper plate 3 covers the upper side of the plate receiving frame 32. The dish receiving rubbers 33 are arranged at a plurality of locations between the dish receiving frame 32 and the upper dish 3.

  In such a configuration, when the weighing object is placed on the upper plate 3, the movable unit 612 receives a load via the upper plate 3, the plate receiving frame 32, the plate receiving rubber 33, and the block 31. Then, the load cell 61 outputs a signal corresponding to the deformation of the strain gauge due to the load to the control unit 7. Then, the control unit 7 calculates a load value based on the output from the load cell 61.

  The overload adjusting unit 65 prevents the load cell 61 from receiving an excessive load in the weighing state. Adjustment of the limit value of the excessive load is performed by changing the screwing position of the overload adjusting portion 65 and the restricted portion 62. In other words, it is performed by adjusting the distance between the lower end of the overload adjusting unit 65 and the upper surface of the lower limiter 63. The adjustment operation can be easily performed from above the frame 21 and the reinforcing plate 23 through the hole 64a.

  When the movable portion 612 receives a load and moves downward, the overload adjusting portion 65 also moves downward. When the lower end reaches the upper surface of the lower restricting portion 63, the overload adjusting portion 65 cannot move any further. Thereby, the movement of the movable part 612 is restricted, and the load cell 61 is prevented from receiving an excessive load.

  The upside down impact adjusting unit 66 prevents the load cell 61 from receiving an excessive load in the direction opposite to that during weighing when the weighing apparatus 1 drops upside down. Adjustment of the limit value of the excessive load is performed by changing the screwing position between the inverted drop impact adjusting unit 66 and the upper limit unit 64. In other words, it is performed by adjusting the distance between the lower end of the inverted drop impact adjusting unit 66 and the upper surface of the restricted portion 62.

  When the scale device 1 receives an impact due to an inverted drop, the movable portion 612 moves upward in FIG. When the upper surface of the restricted portion 62 reaches the lower end of the inverted drop impact adjusting portion 66, the restricted portion 62 cannot move any further. As a result, the movement of the movable portion 612 is restricted, and the load cell 61 is prevented from receiving an excessive load in the direction opposite to that during measurement.

  Thus, according to this embodiment, the installation position of the stopper that protects the load cell 61 from overload and inverted drop impact is summarized, and the number of parts can be reduced by organizing and sharing the components. Moreover, the installation range can be narrowed, and the scale device 1 can be reduced in size. That is, according to the present embodiment, space can be saved.

  In the above embodiment, the restricted portion 62 and the movable portion 612 are separate members. However, in the implementation, the restricted portion 62 and the movable portion 612 are, for example, a predetermined portion of the movable portion 612 is used as the restricted portion. And may be the same member.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

1 ... Weighing device,
2 ... Main body,
21 ... Frame, 21a ... Hole,
211 ... foundation, 212 ... pillar, 213 ... top plate,
22 ... side wall,
23 ... Reinforcing plate,
24 ... Screw,
3 ... the upper plate,
31 ... Block, 32 ... Dish receiving frame, 33 ... Dish receiving rubber,
4 ... operation display panel,
41 ... operation unit, 42 ... display unit,
5 ... Panel for customers,
6 ... load cell unit,
61 ... load cell,
611 ... fixed part, 612 ... movable part,
62 ... Restricted part,
63 ... lower limit part,
64 ... upper limit part, 64a ... hole,
65: Overload adjusting part,
66: Inverted drop impact adjustment unit,
67 ... Bending sheet metal,
7: Control unit.

JP 2002-98597 A

Claims (6)

A load cell that has a fixed portion fixed to the base portion and a movable portion that receives a load to be measured;
An upper restriction portion having a through hole and fixedly provided to the base portion;
A lower restricting portion provided fixedly to the base, and arranged below the upper restricting portion with a space therebetween;
Restricted, fixedly provided with respect to the movable part, located between the upper restricting part and the lower restricting part, and facing the upper restricting part and the lower restricting part with a predetermined gap. And
An overload adjusting part attached to the restricted part so that the distance from the lower restricting part can be freely changed by the adjustment work from above the through hole of the upper restricting part ;
Inverted drop impact attached to the upper limit portion, provided at a position that does not overlap with the overload adjustment portion in plan view, so that the distance from the restricted portion can be changed by adjustment work from above the upper limit portion. An adjustment unit;
A load cell unit comprising: The load cell unit according to claim 1, wherein the overload adjusting unit and the inverted drop impact adjusting unit are arranged at positions shifted in a direction from the fixed unit toward the movable unit. The load cell unit according to claim 1 or 2, wherein the restricted portion protrudes from the movable portion toward a side away from the fixed portion. The load cell unit according to any one of claims 1 to 3, wherein the restricted portion extends in a horizontal direction from an end of the movable portion. The load cell unit according to any one of claims 1 to 4, wherein both or one of the overload adjusting unit and the inverted drop impact adjusting unit is a screw that is screwed into an attachment partner. The load cell unit according to any one of claims 1 to 5,
An upper plate connected to the load cell unit and on which a weighing object is placed;
A control unit that calculates the weight of the measurement object based on an output from the load cell unit;
A scale device comprising:

Images