Metering device

Abstract

To reduce the height of a load from the ground when a weighing device is used for weighing the load.SOLUTION: A support plate having an upper plate surface and a lower plate surface and comprising a load object region for receiving a load object, two or more connector regions extending at an angle from the load object region, and two or more flanges each extending at an angle from one of the two or more connector regions, and at least three weighing units distributed on the two or more flanges for supporting the support plate on a ground surface; The load body rests on the upper plate surface of the load body region, and each of the at least three weighing units comprises a resilient plate extending from one of the two or more flanges and converts a detected degree of deformation caused by the load body on the load body region into an electrical signal corresponding to the weight of the load body, wherein the upper plate surface of the load body region is below the resilient plate of each of the at least three weighing units.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a weighing device, and in particular to a weighing device equipped with a load cell. [Background technology]

[0002] A load cell is a device that converts force (e.g., tension, compression, pressure, etc.) into a measurable electrical signal. There are eight main types of load cells: photoelectric, hydraulic, electromagnetic, capacitance, magnetic pole change (magnetostrictive), vibration, gyro, and resistive strain. Of these types, resistive strain load cells are the most widely used type of load cell.

[0003] In a resistive strain load cell, an elastic element is elastically deformed by the action of an external force. This also deforms a resistive strain gauge attached to the surface of the elastic element. As the resistive strain gauge deforms, its resistance value changes. These resistance values ​​are detected and measured by a measurement circuit. The measurement circuit is configured to convert the change in resistance value into an electrical signal. A transmission cable may be provided to communicate the electrical signal to other devices for further processing or utilization.

[0004] A typical weighing device comprises a load support plate (bearing plate) below which one or more load cells are placed. When an external weight is placed on the load support plate, the elastic elements and resistance strain gauges of the load cells are deformed. As a result, the measurement circuit of each load cell converts the change in resistance of the resistance strain gauge into an electrical signal corresponding to the force acting on it (the force from the external weight).

[0005] The load support plate of a typical weighing device is generally flat, and the load cell is located on the underside of the load support plate. Therefore, the suspended height (hanging height) of the external weight is equal to the sum of the thicknesses of the load support plate and the load cell. In some cases, for example, for weighing devices installed under the legs or wheels of a sleep monitoring bed, the rest height (i.e., the height of the center of gravity) of a heavy object should not be too high. If the rest height of the bed's legs or wheels is too high and the bed's weight is too heavy, the center of gravity will move upward, reducing the stability of the bed. This can make the weighing device more difficult to install. Summary of the Invention

[0006] In one aspect, the weighing device includes a support plate. At least three weighing units are distributed at non-linear intervals on a lower plate surface of the support plate. The at least three weighing units stably support the support plate. A central portion of the support plate faces downward. The central portion forms a load body area for placing a load body. Flanges are formed at ends of the central portion. The flanges are configured to be attached to the weighing units. When subjected to a maximum load, the lower plate surface of the load body area does not become lower than the contact point of the weighing units with the ground.

[0007] In another aspect, a weighing device for measuring the weight of a load comprises a bearing plate and at least three weighing units. The bearing plate comprises an upper plate surface and a lower plate surface. The bearing plate further comprises a load region, two or more connector regions, and two or more flanges. The load region receives the load with the load disposed on the upper plate surface of the load region. The two or more connector regions extend at an angle from the load region. Each of the two or more flanges extends at an angle from one of the two or more connector regions. The at least three weighing units are distributed among the two or more flanges and adapted to support the bearing support plate on the ground. Each of the at least three weighing units comprises an elastic plate extending from one of the two or more flanges. Each of the at least three weighing units is configured to convert a detected degree of deformation caused by the load on the load region into an electrical signal corresponding to the weight of the load. The upper plate surface of the load region is below the elastic plate of each of the at least three weighing units.

[0008] In yet another embodiment, the lower plate surface of each of the two or more flanges is 1 mm to 4 mm above the upper plate surface in the load body region.

[0009] In a further embodiment, the at least three metering units comprise four metering units, each of the four metering units being located near a corner of the support plate.

[0010] In yet a further aspect, the load region is substantially planar.

[0011] In another embodiment, each of the at least three weighing units further includes a resistance strain gauge and a support member. The resistance strain gauge is attached to both the elastic plate and one of the two or more flanges. The support member is adapted to connect to the elastic plate and contact the ground. A contact point between the support member and the ground is below a lower plate surface in the load region.

[0012] In yet another aspect, the resilient plate and the support plate are formed from a single sheet of material.

[0013] In yet another embodiment, a resistive strain gauge is attached to the lower plate surface of one of the two or more flanges.

[0014] In a further aspect, the resilient plate comprises an upper resilient plate surface and a lower resilient plate surface, and the resistive strain gauge is attached to the lower resilient plate surface.

[0015] In yet a further aspect, the resilient plate includes a central beam attached to one of the two or more flanges and two lateral beams extending on either side of the central beam, the support members adapted to connect the lateral beams and cross the central beam without contacting it.

[0016] In yet another embodiment, the resilient plate further comprises a plate body, wherein the central beam and the two lateral beams are attached to the plate body.

[0017] In another embodiment, the support member comprises two wings and a central body extending between the two wings.

[0018] In yet another embodiment, each of the two wings connects to one of the side beams.

[0019] In yet another embodiment, the weighing device further comprises a fastener for attaching each of the two wings to one of the side beams.

[0020] In a further aspect, the central body is arched and straddles the central beam but does not contact the central beam.

[0021] In yet a further aspect, at least a portion of the resistive strain gauge extends between the central body and the central beam.

[0022] In yet another further aspect, at least a portion of the central body is adapted to contact the ground.

[0023] In yet a further aspect, at least a portion of the central body adapted to contact the ground is located approximately in the middle of the length of the resistive strain gauge.

[0024] In another embodiment, one or more of the resistive strain gauges is covered with a flexible seal.

[0025] In yet another embodiment, each of the resistive strain gauges is electrically connected to the controller interface using one or more wires.

[0026] In yet another embodiment, each of the resistive strain gauges is connected via one or more wires to form a full bridge circuit configuration.

[0027] The rest height of the load is equal to the height of the upper plate surface of the load area from the ground. Since the load area is formed by the downward deflection and recess in the central part of the support plate, the upper plate surface of the load area can be lower than the upper plate surface of the flange. Said height above the ground may be smaller than the sum of the thicknesses of the flange and the weighing unit. Therefore, when the weighing device is used to weigh a load, the height of the load from the ground can be reduced accordingly. This increases the range of application and the stability of the load during the weighing process.

[0028] The above description is intended to be merely a summary and only a portion of the aspects of the present invention. The above description is not intended to define the limitations or requirements of the present invention. Other aspects of the present invention will be understood by reference to the detailed description of the preferred embodiments.

[0029] The present invention will now be described with reference to the detailed description of the embodiments and the drawings. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 shows a top perspective view of a metering device according to one embodiment. [Figure 2] FIG. 2 shows a bottom perspective view of the metering device. [Figure 3] FIG. 3 shows a side view of the metering device. [Figure 4] FIG. 4 is an enlarged view of a portion A of FIG. [Figure 5] FIG. 5 shows a top view of the metering device. [Figure 6] FIG. 6 shows a bottom view of the metering device. [Figure 7] FIG. 7 shows an enlarged top perspective view of one of the metering units of the metering device. [Figure 8] FIG. 8 shows an enlarged side view of one of the metering units. [Figure 9] FIG. 9 shows an enlarged bottom perspective view of one of the metering units. DETAILED DESCRIPTION OF THE INVENTION

[0031] 1 and 2, the weighing device 10 includes a support plate (bearing plate) 12 and a plurality of weighing units 14 extending from the support plate 12. The support plate 12 includes an upper plate surface 16 and a lower plate surface 18 and may be constructed of a metal such as steel. The weighing units 14 may be distributed nonlinearly around the periphery of the support plate 12. In some embodiments, the number of weighing units 14 may be four, while in other embodiments, the number of weighing units 14 may be three, five, or more. The weighing units 14 may include load cells and may be adapted to stably support the support plate 12.

[0032] The support plate 12 may be folded to form a load region 20 for supporting or receiving a load 1. By way of example only, in the embodiment shown in Figure 1, the support plate 12 includes the load region 20 between two connector regions 22, with a flange 24 extending from each of the two connector regions 22. The load region 20, the two connector regions 22, and the two flanges 24 may be formed by folding a single sheet of material, such as steel or other suitable metal.

[0033] 1, the weighing units 14 may extend from the support plate 12 near or at the flange 24. Each of the weighing units 14 may include a lower unit surface 26 (best shown in FIG. 4). At least two of the lower unit surfaces 26 of the weighing units 14 simultaneously contact the ground 2. The contact of the lower unit surfaces 26 of the weighing units 14 with the ground 2 may provide a stable base for the weighing apparatus 10.

[0034] 3 and 4, the weighing device 10 is configured so that when the load 1 is placed on the load area 20, the lower plate surface 18 does not become lower than the lower unit surface 26 of the weighing unit 14, even if the load 1 is at its maximum weight for the weighing device 10. In other words, the lower plate surface 18 should be higher than the lower unit surface 26.

[0035] In some embodiments, the weighing units 14 may be positioned near the corners of the support plate 12, extending from the flanges 24. For example, as shown in FIG. 1 , two of the weighing units 14 may extend from each of the flanges 24. The support plate 12 may be folded, for example, at two first edges 28 (between the load region 20 and the connector region 22) to form the load region 20. The load region 20 may be substantially rectangular in shape and substantially planar. In some embodiments, the load region 20 may have a length (i.e., the distance between the two first edges 28) of approximately 120 mm and a width of approximately 100 mm, although it will be understood that other dimensions are possible. The flanges 24 may be formed by further folding the support plate 12 at two second edges 30 (between the connector region 22 and the flanges 24). The connector region 22 may be angled relative to the load body region 20 and the flange 24 (i.e., the connector region 22 need not be perpendicular to the load body region 20 or the flange 24). For example, in some embodiments, the angle B (shown in FIG. 4) between the load body region 20 and the connector region 22 may be between 100° and 140°. In some embodiments, the angle B may be approximately 120°. It is understood that other values ​​for the angle B are possible.

[0036] In some embodiments, the shape of the bearing plate 12 can take other forms, such as a hexagon, a pentagon, a triangle, etc.

[0037] When the load 1 is placed on or engaged with the upper plate surface 16 of the load area 20, a downward pressure is applied to the load area 20. This downward pressure is transmitted to the flange 24 via the connector area 22, thereby applying pressure to the weighing unit 14. This pressure can be measured by the weighing unit 14. At the same time, the downward pressure acting on the load area 20 can cause the lower plate surface 18 of the load area 20 to move downward. However, even if the load 1 is at its maximum weight for the weighing device 10, the lower plate surface 18 is still above the contact point between the lower unit surface 26 of the weighing unit 14 and the ground 2. This prevents the load area 20 from contacting the ground 2. Such contact could adversely affect measurements made by the weighing unit 14.

[0038] In some embodiments, the weighing device 10 may be mounted on a support base rather than directly on the ground 2. However, the operation of the weighing device 10 may be similar to that disclosed herein.

[0039] 4, the suspended height (hanging height) of the load body 1 may be equal to the height of the upper plate surface 16 of the load body region 20 from the ground 2. This is because the load body region 20 is formed by bending the support plate 12, thereby forming an area that is depressed relative to the flange 24 (e.g., where the weighing unit 14 may be located). In other words, the upper plate surface 16 of the load body region 20 may be lower than the upper plate surface 16 of the flange 24. The height C of the upper plate surface 16 of the load body region 20 from the ground 2 may be smaller than the sum D of the thickness of the flange 24 and the thickness of the weighing unit 14.

[0040] In some embodiments, the difference between D and C may be 4 mm to 6 mm (i.e., the distance between the upper plate surface 16 of the flange 24 and the upper plate surface 16 of the load body region 20). In some embodiments, the difference between D and C is approximately 5 mm.

[0041] In some embodiments, the support plate 12 may be between 2 mm and 3 mm thick. In some embodiments, the support plate 12 may be approximately 2.5 mm thick.

[0042] Thus, the distance E between the lower plate surface 18 of the flange 24 and the upper plate surface 16 of the load body region 20 may be between 1 mm and 4 mm. If the difference between D and C is approximately 5 mm and the support plate 12 is approximately 2.5 mm thick, the distance E may be approximately 2.5 mm.

[0043] Therefore, when the weighing device 10 is used to measure the weight of a load 1, the height of the load 1 from the ground 2 (i.e., the height of the center of gravity of the load 1) can be made lower compared to a completely flat support plate 12. This allows the weighing device 10 to be used in a wider range of applications and improves the stability of the load 1 during the weighing process.

[0044] 5 and 6 , the flange 24 may include an outer flange edge 34 extending near a corner of the support plate 12. Each of the weighing units 14 includes a resilient plate 32 that may extend from the outer flange edge 34. The resilient plate 32 may include an upper resilient plate surface 38 and a lower resilient plate surface 40. In some embodiments, the resilient plate 32 is continuous with and integral with the flange 24. In other words, as shown in FIG. 5 , the resilient plate 32 may be formed from the same sheet of material as the flange 24 (and optionally the support plate 12). In other embodiments, the resilient plate 32 may instead be connected to the flange 24, for example, to the lower plate surface 18 of the flange 24. Each of the weighing units 14 may further include a resistance strain gauge 36 extending across at least a portion of the resilient plate 32 and at least a portion of the flange 24. In some embodiments, the resistance strain gauge 36 may be attached to a portion of the lower plate surface 18 of the flange 24 and a portion of the lower resilient plate surface 40. In other embodiments, resistive strain gauges 36 may be attached to a portion of upper plate surface 16 and a portion of upper resilient plate surface 38 .

[0045] Each of the weighing units 14 may further include a support member 42 that may be attached to the lower resilient plate surface 40. The support member 42 at least partially defines the lower unit surface 26 and may be in contact with the ground 2. The contact point between the support member 42 and the ground 2 is not higher than the lower plate surface 18 of the load body region 20 under maximum load.

[0046] When weighing device 10 is placed on ground 2 via contact of support members 42 with ground 2, support plate 12 and elastic plate 32 may be suspended (i.e., suspended by resistance strain gauge 36). When load 1 is placed on load area 20, upward bending occurs at the intersection of elastic plate 32 and flange 24. Because resistance strain gauge 36 traverses both elastic plate 32 and flange 24 (attached to lower elastic plate surface 40 and lower plate surface 18 of flange 24), resistance strain gauge 36 also bends upward. This results in a measurable change in the resistance of resistance strain gauge 36.

[0047] In some embodiments, the elastic plate 32 and the support plate 12 may be stamped or formed from the same sheet of material. In such embodiments, the resistance strain gauges 36 may be attached to the same sheet of material (e.g., steel). Under such circumstances, using the same sheet of material results in a relatively high degree of performance consistency. The degree of bending or curvature between the elastic plate 32 and the flange 24 under the action of the load 1 is relatively consistent for each of the metering units 14, improving measurement accuracy.

[0048] 7-9, in some embodiments, the resilient plate 32 includes a central beam 44 and a plate body 46 extending from the central beam 44. The central beam 44 is attached to the flange 24. The resilient plate 32 further includes side beams 48 extending from the plate body 46, the side beams 48 extending at least partially along the length of the sides of the central beam 44. The side beams 48 may not contact the outer flange edge 34. In some embodiments, the side beams 48 are symmetrically positioned along the sides of the central beam 44.

[0049] The support member 42 may include two wings 50. A central body 52 extends between the two wings 50. Each of the wings 50 may be configured to engageably connect to one of the side beams 48, for example, using fasteners 54. The fasteners 54 may be pins, bolts, rivets, screws, or the like. The central body 52 may be arch-shaped and may straddle, but not contact, the central beam 44. In some embodiments, at least a portion of the resistance strain gauges 36 extend above the central body 52. ​​At least a portion of the resistance strain gauges 36 extend between the central body 52 and the central beam 44.

[0050] The central beam 44 is attached to the flange 24 to ensure precision in force transmission. If the lateral beams 48 are arranged symmetrically along the sides of the central beam 44, the stability of force transmission by the elastic plate 32 is improved. On the other hand, the precision in force also provides a mounting base for the support members 42, thereby improving the stability of the weighing device 10 as a whole. At least a portion of the central body 52 may comprise the lower unit surface 26.

[0051] In some embodiments, the lower unit face 26 may be located below approximately the middle of the length of the resistance strain gauge 36. In some embodiments, the resistance strain gauge 36 may also extend longitudinally along approximately the centerline between two fasteners 54 used to connect the wing 50 to the side beam 48.

[0052] In some embodiments, the resistance strain gauges 36 may be covered with a flexible seal, which not only improves the accuracy of force transmission but also protects the resistance strain gauges 36 and prevents external contamination, thereby extending the useful life of the weighing device 10.

[0053] Referring again to FIG. 2 , in some embodiments, the resistance strain gauges 36 may be electrically connected to a controller interface 56 provided on the weighing device 10 using one or more wires 58. The resistance strain gauges 36 may be configured to bend under force and convert the detected force into an electrical signal. The electrical signal is then transmitted to the controller interface 56 using the wires 58. The controller interface 58 may be configured to determine the weight of the load 1 using the electrical signals received from the resistance strain gauges 36. Depending on the position of the load 1 on the load region 20, the amount of strain in each of the resistance strain gauges 36 may be different, and therefore the electrical signals transmitted by the resistance strain gauges 36 may be different. The controller interface 56 may be configured to determine the weight of the load 1 by taking into account the different electrical signals from the resistance strain gauges 36. An external controller may also be connected to the controller interface 56 to read the electrical signals from the resistance strain gauges 36.

[0054] In some embodiments, each of the resistive strain gauges 36 may be connected by wires 58 to form a full-bridge circuit configuration (e.g., a Wheatstone bridge), thereby reducing the number of wires 58 required to connect the resistive strain gauges 36 to an external controller. This may improve the reliability and stability of the weighing device 10, and may make the weighing device 10 easier to assemble.

[0055] Those skilled in the art will appreciate that although preferred embodiments have been described in detail, modifications may be made without departing from the principles of the invention.

Claims

1. 1. A weighing device for measuring the weight of a load, said weighing device comprising: a support plate having an upper plate surface and a lower plate surface, the support plate including: a load body region for receiving the load body; two or more connector regions extending at an angle from the load body region; and two or more flanges each extending at an angle from one of the two or more connector regions; at least three weighing units distributed among the two or more flanges and adapted to support the support plate on the ground; Equipped with the load body is placed on the upper plate surface in the load body region; each of the at least three metering units includes a resilient plate extending from one of the two or more flanges; each of the at least three weighing units is configured to convert a detected degree of deformation caused by the load on the load area into an electrical signal corresponding to the weight of the load; the upper plate surface of the load region is below the elastic plate of each of the at least three weighing units; Weighing device.

2. the lower plate surface of each of the two or more flanges is 1 mm to 4 mm above the upper plate surface of the load body region; The weighing device according to claim 1 .

3. the at least three metering units comprise four metering units; Each of the four weighing units is located near a corner of the support plate. The weighing device according to claim 1 .

4. The load region is substantially planar. The weighing device according to claim 1 .

5. Each of the at least three metering units comprises: a resistive strain gauge attached to both the elastic plate and the one of the two or more flanges; a support member connected to the resilient plate and adapted to contact the ground; Furthermore, The contact point between the support member and the ground is below the lower plate surface of the load body region. The weighing device according to claim 1 .

6. the resilient plate and the support plate are formed from a single sheet of material; 6. The weighing device according to claim 5.

7. the resistance strain gauge is attached to a lower plate surface of the one of the two or more flanges; 6. The weighing device according to claim 5.

8. the elastic plate has an upper elastic plate surface and a lower elastic plate surface; the resistive strain gauge is attached to the lower elastic plate surface; 6. The weighing device according to claim 5.

9. The elastic plate is a central beam attached to said one of said two or more flanges; two side beams extending on either side of the central beam; Equipped with the support members are adapted to connect the side beams together and cross the central beam without contacting it; 6. The weighing device according to claim 5.

10. The elastic plate further includes a plate body, The central beam and the two side beams are attached to the plate body; 10. The weighing device of claim 9.

11. The support member is Two wings and a central body extending between the two wings; Equipped with 11. The weighing device of claim 10.

12. Each of the two wings connects to one of the side beams.

12. The weighing device of claim 11.

13. the weighing device further comprising a fastener for attaching each of the two wings to one of the side beams; 13. The weighing device of claim 12.

14. the central body is arched and straddles the central beam but does not contact the central beam; 13. The weighing device of claim 12.

15. at least a portion of the resistive strain gauge extends between the central body and the central beam; 15. The weighing device of claim 14.

16. At least a portion of the central body is adapted to contact the ground.

16. The weighing device of claim 15.

17. the at least one portion of the central body adapted to contact the ground is located approximately in the middle of the length of the resistance strain gauge; 17. The weighing device of claim 16.

18. one or more of the strain gauges are covered with a flexible seal; 6. The weighing device according to claim 5.

19. each of the resistive strain gauges electrically connects to a controller interface using one or more wires; 6. The weighing device according to claim 5.

20. each of the resistive strain gauges is connected via the one or more wires to form a full bridge circuit configuration; 20. The weighing device of claim 19.

Images