JPH0843184A - Multirange load cell scale - Google Patents

Abstract

PURPOSE:To provide a multirange load cell scale equipped with a stopper mecha nism for stopping the impact force more effectively upon falling of a heavy object. CONSTITUTION:The multirange load cell scale comprises a high weighing capacity load cell 2 and a low weighing capacity load cell 3 wherein a weighing pan 10 is supported by a pan receiving part 4 equipped with a butter mechanism 4a on the side of the center of gravity 3a of the low weighing capacity load cell 3. The multirange load cell scale is further comprises first stoppers 51a-51c abutting on a member disposed closer to the weighing pan 10 than the butter mechanism 4a at the pan receiving part 4 when the weighing pan 10 is pushed down beyond a predetermined level, and a second stopper 52 abutting on a member 47 disposed on the side of the center of gravity of the low weighing capacity load cell 3. This structure absorbs the inertia of a heavy object in two stages thus protecting the low weighing capacity load cell against damage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a multi-range load cell balance which is a combination of a high weighing load cell and a low weighing load cell.

[0002]

2. Description of the Related Art A multi-range load cell for weighing a wide load range from low load to high load with high accuracy comprises a high weighing load cell and a low weighing load cell, and the fulcrum side of the high weighing load cell is the main body. The load cell is attached and fixed to the side member, and the fulcrum side of the low-weighing load cell is fixedly supported on the load cell side. Then, the dish receiving portion is attached and supported on the important side of the low weighing load cell via a buffer mechanism made of an elastic material such as a spring plate, and the weighing tray is horizontally supported by the dish receiving portion.

[0003]

In the conventional multi-range load cell as described above, a heavy object far exceeding the weight of the low weighing load cell may be placed on the weighing pan. If the device is placed on the weighing pan so as to be dropped, the impact force at that time may be applied to the low weighing load cell and may be damaged.

Conventionally, there has been provided a stopper which comes into contact with a dish receiving portion from below in order to receive an overload applied to a low weighing load cell when a heavy object is placed as described above (Japanese Patent Application Laid-Open No. SHO 61-96). 61-96422). However, as described above, in the case where the stopper that comes into contact with the dish receiving portion is provided, the inertial force when the heavy object is placed on the weighing dish so as to drop is received by only one central stopper. Therefore, there is a risk that a large impact will be directly applied to the strain generating portion without damaging it when the stopper comes into contact with the stopper, resulting in damage. On the other hand, as described above, it is possible to prevent the load cell from being damaged by sufficiently absorbing the load applied to the weighing pan by the shock absorbing mechanism or shock absorbing member of the dish receiving portion. In order to absorb the force sufficiently, it is necessary to take a large stroke in the height direction, which causes a problem that the height dimension of the scale becomes large.

It is an object of the present invention to provide a multi-range load cell balance as described above with a stopper mechanism capable of more effectively receiving an impact force when a heavy object is dropped, so that the height dimension of the balance can be improved. The purpose is to effectively prevent breakage of the low weighing load cell without increasing the load.

[0006]

In order to achieve the above object, the present invention comprises a high weighing load cell and a low weighing load cell, wherein the fulcrum side of the high weighing load cell is attached and fixed to a main body member, The fulcrum side of the low weighing load cell is fixedly supported on the emphasis side of the high weighing load cell, and the dish receiving part is mounted and supported on the emphasis side of the low weighing load cell via a buffer mechanism that elastically receives the vertical load. In a multi-range load cell balance in which a weighing pan is supported horizontally by a section, when the weighing pan is pushed down beyond a predetermined level, a first stopper that abuts against a member on the weighing pan side of the buffer mechanism, and a buffer A second stopper that comes into contact with a member on the weight side of the load cell having a lower weight than the mechanism is provided.

The multi-range load cell scale described above
The weighing dish and the dish receiving portion may be configured to be separable, and the first stopper may be configured to contact the weighing dish from below. Further, in the multi-range load cell scale, it is effective that the cushioning mechanism is configured by a Roberval mechanism in which two elastic plate members are arranged horizontally and in parallel and both ends of these elastic plate members are connected to each other.

[0008]

According to the above means, the high weighing load cell is attached and fixed to the base side member, and the fulcrum side of the low weighing load cell is attached and supported on the emphasis side thereof. In addition, a plate receiving portion is mounted and supported on the emphasis side of the low weighing load cell via a buffering mechanism that elastically receives a vertical load applied from the weighing pan, and the weighing plate is supported horizontally by this plate receiving portion. .

The balance of the present application is provided with a first stopper and a second stopper. For example, when a heavy object is dropped onto the weighing pan, the load causes the weighing pan to be pushed down beyond a predetermined level, and this load is applied to the priority side of the low weighing load cell via the buffer mechanism of the pan receiving portion. . This time,
The first stopper comes into contact with a member closer to the weighing pan than the buffer mechanism, receives the load, and reduces the inertial force. In addition, since the shock generated when the first stopper abuts is absorbed by the buffer mechanism, it is not transmitted to the low weighing load cell. further,
The second stopper abuts on the load side of the load cell having a lower weight than the buffer mechanism and receives the reduced residual inertial force applied to the load side of the load cell.

Further, in the case where the weighing pan and the pan receiving portion are separable from each other, when the weighing pan is pushed down beyond a predetermined level by dropping a heavy object, the first stopper comes into contact with the weighing pan and descends. Support the weighing pan from below. When the weighing pan is supported by the first stopper, the pan receiving portion that continues to descend due to inertia separates from the weighing pan. Then, only the load of the pan receiving portion that drops due to inertia is applied to the low-weighing load cell on the priority side. Even in this case,
The second stopper comes into contact with the weighting side of the low-weighing load cell from below relative to the buffer mechanism, and receives the remaining inertial force applied to the weighting side of the load cell.

Further, in the above-mentioned dish receiving part having a buffer mechanism constituted by a Roberval mechanism, two elastic plates are provided horizontally and parallel to each other, one end of which is on the side of the low-loading load cell on the weight side and the other is on the other side. The end is fixed to the dish receiving member, and the two members are connected. Therefore, when a load is applied to the weighing pan,
Both elastic members described above elastically deform while maintaining parallelism, and the weighing pan descends / rises substantially vertically.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. 1 to 7 show a multi-range load cell scale embodying the present invention. The multi-range load cell load cell scale described above is a main body case 1 formed in a flat box shape.
Inside, the high weighing load cell 2 and the low weighing load cell 3 are arranged so as to be connected in a vertically stacked manner, and the dish receiving portion 4 equipped with the buffer mechanism 4a is attached to the fulcrum side 3a of the low weighing load cell 3 described above. The weighing pan 10 is supported and held in a horizontal state by the pan receiving portion 4. Four protrusions are provided on the upper surface of the weighing dish 10 so that the cylindrical article does not roll.

As shown in FIGS. 6 and 7, the main body case 1 is constructed by combining an upper case 1b having an upper surface opening 1b 'and a lower case 1a so as to be openable and closable, and a bottom surface part of the lower case 1a. Leg members 1d for height adjustment are screwed on the four corners. A circuit board 1h is provided inside the lower case 1a.
The power supply board 1i, the circuit board 1k of the display unit 1j on the front of the case 1, and the like are arranged.

Further, a substantially dish-shaped substrate 1c made of a metal plate is laid on the bottom surface of the lower case 1a and fixed to the lower case 1a, and strip-shaped metal plates are provided at the four corners of the substrate 1c. The receiving plates 1e and 1g, which are formed into a bent shape, are arranged, and a base 9 described later is provided between these receiving plates 1e and 1g.
The four corners are inserted.

A fastening plate 1m is fixedly provided on one side of the substrate 1c of the lower case 1a. The fulcrum side 2a of the high weighing load cell 2 is placed on the upper surface of the fastening plate 1m, and the fulcrum side is placed on the fulcrum side. It is fastened and fixed by two bolts 21 which vertically pass 2a. The high weighing load cell 2 is a flexure element that measures a load in the range of 1 kg to 30 kg, and a substantially H-shaped lightening hole 22 is formed in the central side surface of a square columnar metal block.
Strain gauges 23 for electrically converting a mechanical strain amount are attached to both upper and lower surfaces of the strain-flexing portion. As described above, the high weighing load cell 2 has the bolt 21 at the end of the fulcrum side 2a.
The horizontal side is maintained by being stopped, and it is attached and fixed in a cantilevered state to the substrate 1c, which is the tip side 2 which is the tip.
b to the fulcrum side 3a of the low weighing load cell 3 via the base 9
Are attached and supported by two bolts 31.

The low weighing load cell 3 is a flexure element capable of weighing up to 3 kg. In order to increase the safety factor of the flexure element, 1
It is set so that only a load within the range of kg or less is measured, and like the high weighing load cell 2 described above, a substantially H-shaped lightening hole 32 is formed in the side surface of the central portion of the square pole-shaped metal block. Strain gauges 33 are attached to both upper and lower surfaces of the strain-flexing portion. As shown in FIGS. 1 and 6, the base 9 is composed of a base plate 9a having a square opening in the center and a box-shaped box member 9b having an open top surface. Both members 9a in a form covered from below by 9b,
It is configured by integrating 9b. In addition, a strip-shaped extension plate 9c is attached to one side of the bottom surface of the box member 9b of the base 9 and extends horizontally with its tip facing outward.

The low weighing load cell 3 is housed inside the base 9, and two bolts 31 vertically passed through the fulcrum side 3a thereof penetrate the bottom surface of the box member 9b of the base 9 so that the high weighing load cell 2 It is screwed to the important point side 2b. As a result, the base 9 is held between the load cells 2 and 3 in a state where one end of the base 9 is sandwiched by the ring-shaped spacer 31a with the bolt 31 interposed therebetween, and the base 9 is maintained in a horizontal state together with the low weighing load cell 3, and Weighing load cell 2
It is held in a cantilever state with respect to the emphasis side 2b. The low weighing load cell 3 is supported in a floating state inside the box member 9b of the base 9, and a necessary gap is provided between the load cell 3 and the box member 9. Further, an upper holding plate 9d having a substantially T shape in a plan view is provided on the upper portion of the base 9. The upper mounting plate 9d is a mounting member for a stopper 56, which will be described later, and has three ends fixed to the base plate 9a with screws 9e.
The base plate 9a is mounted and supported in a state of being slightly floating above the upper surface thereof.

A plate receiving portion 4 is mounted and supported on the weight side 3b of the low weighing load cell 3 via an elastic mechanism 4a. As shown in FIG. 2 and FIG. 5, the dish receiving portion 4 holds the dish receiving plate 4b for supporting the weighing dish 10 and the plate receiving plate 4b horizontally and with respect to the weight side 3b of the low weighing load cell 3. And a cushioning mechanism 4a that elastically attaches and supports it.

The buffer mechanism 4a comprises a pair of Roberval mechanisms 41.
It consists of As shown in FIGS. 5 and 4, the Roberval mechanism 41 has two strip-shaped spring plates 42 arranged in parallel, and both ends of these spring plates 42 are connected bodies 43 having a U-shaped cross section.
, And they are fastened and fixed by two bolts 44. Further, the base end of the friction spring plate 45 is fastened together with the one connecting body 43, and the tip end thereof is elastically brought into contact with the upper spring plate 42. Furthermore, since the pair of Roberval mechanisms are arranged so as to sandwich the low weighing load cell 3, the height of the entire weighing machine can be suppressed. The Roberval mechanism 41 configured as described above supports both spring plates 42 when one end is supported in a horizontal state and the other end is pushed down from above.
Deform while maintaining parallelism, whereby the connecting body 43 at the other end vertically descends / rises.

The pair of Roberval mechanisms 41 constructed as described above are arranged on both sides of a bearing member 46 having a U-shaped cross section, and extend portions 46a extended from both ends of one end of the bearing member 46. On the other hand, a screw 46b is fastened to the mechanism 41 side 41b of the mechanism 41 to hold them horizontally. The fulcrum side 41a of both the Roberval mechanisms 41 is fixed to the connecting member 47 bent in a U-shaped cross section from the side surface as shown in FIGS. They are integrally connected by a connecting member 47. The connecting member 47 is placed so as to straddle the upper surface of the weight side 3b of the low weighing load cell 3, and is fixed to the weight side 3b by the two bolts 44 as described above. Therefore, in both Roberval mechanisms 41, the fulcrum side 41a is horizontally supported in a cantilever state with respect to the weight side 3b of the low weighing load cell 3, and the bearing member 46 is held at the weight side 41b at the tip thereof. .

Further, the connecting member 47 forms a mounting piece 47a extending outward, and the mounting piece 47a is inserted into the gap formed between the upper pressing plate 9d and the base 9 described above. Supported by shape. Incidentally, the above-mentioned mounting piece 47a
Is for attaching and fixing a second stopper 52 described later. The center of the support member 46 is the double Roberval mechanism 41.
It is located in the center of and protrudes upward from that position. Further, a receiving plate 48 is attached and fixed to the upper surface of the support member 46, the central portion of the dish receiving plate 4b is placed on the receiving plate 48, and is screwed with a screw 48a. Plate support plate 4b
Is a plate material that is one size smaller than the weighing pan 10. Circular contact members 49 are provided at the four corners of the upper surface, and the contact members 49 support the weighing plate 10 from below.
That is, the weighing pan 10 is only placed on the plate receiving plate 4b, and can be freely picked up from the plate receiving plate 4b.

The multi-range load cell balance described above includes the first stopper 51, the second stopper 52, and the stopper 53.
Each stopper up to stopper 58 is provided. First
The stopper 51 comes into contact with a member on the weighing dish 10 side of the buffer mechanism 4a of the dish receiving portion 4 when a heavy object that exceeds the weighing capacity of the low weighing load cell 3 is placed on the weighing dish 10. As shown in FIG. 6, four first stoppers 51a provided at the four corners of the upper surface of the base 9, two first stoppers 51b provided on each side of the opening, and at the center of these first stoppers 51b. First stopper 51 to be provided
It is composed of a total of 10 stoppers of c.

Each of the above-mentioned first stoppers 51a to 51c is composed of a bolt, and its tip is screwed vertically to a female screw base 51d mounted and fixed at a predetermined position on the upper surface of the base 9, and at the same time, the nut 51e is fixed. By tightening, the height of the stopper can be finely adjusted within the required range. In addition, each of the above-mentioned first stoppers 51a to 51c penetrates the upper surface of the upper case 1b and the dish receiving plate 4b, and
It projects to the bottom of the weighing pan 10 placed on b.

When the weighing pan 10 is further pushed down by placing a heavy object on the weighing pan 10 that exceeds the weighing capacity of the low weighing load cell 3, the above-mentioned first stoppers 51a and 51b simultaneously contact the lower surface of the weighing pan 10. Contact. Further, the two first stoppers 51c are the stoppers 51a and 51b described above.
The rubber plate 10a is set to be slightly shorter than that and elastically contacts the rubber plate 10a attached to the lower surface of the weighing pan 10.

The above-mentioned first stopper 51c is the other first stopper.
The height is adjusted so that the stoppers 51a and 51b come into contact with the rubber plate 10a somewhat earlier than the case where the stoppers 51a and 51b come into contact with the lower surface of the weighing pan 10.
The impact when abutting against is mitigated. In addition, each first stopper 5
When 1a to 1c contact the lower surface of the weighing pan 10, the weighing pan 10
Are supported by the respective first stoppers 51a to 51c, and subsequently, the pan receiving plate 4b which descends due to inertia is separated from the lower surface of the weighing pan 10. The extending portion 47a of the connecting member 47 that connects the fulcrum side 41a of both the Roberval mechanisms 41 is inserted into a gap formed between the base plate 9a and the upper pressing plate 9d, and the second stopper 52 is attached to this inserting portion. It is provided.

The second stopper 52 is the low weighing load cell 3
This is to prevent the important side 3b of the above from being pushed down by an inertial force due to an overload, and the axial screw is threaded vertically through the extending portion 47a of the connecting member 47, and its lower end is It is in contact with the upper surface of the base 9. Further, the second stopper 52 is adapted to finely adjust the amount of protrusion to the lower surface side by tightening the nut 52a.
The second stopper 52 is the first stopper 5 described above.
1a to 1c are adjusted so as to contact the upper surface of the base 9 after contacting the weighing pan 10, and when the inertial force due to the load reaches a predetermined value or more, the downward load is applied to the weight side 3b of the low weighing load cell 3. The inertial force of 1 is received instead of the low weighing load cell 3. For example, the second stopper 52 is adjusted so as to come into contact with the upper surface of the base 9 when a load of 25 kg is dropped on the weighing pan 10 from a height of 15 cm.

The stopper 58 provided on the bottom surface of the substrate 1c laid on the lower case 1a is for preventing the weight side 2b of the high weighing load cell 2 from being pushed down beyond an allowable amount due to overload. -Shaped screws are screwed vertically upward with respect to the bottom surface of the base plate 1c, and the upper ends thereof are located immediately in front of the lower surface on the weight side of the high weighing load cell 2. Incidentally, the stopper 58 is also adapted to finely adjust the amount of protrusion to the upper surface side by tightening the nut similarly to the second stopper 52 described above.

The plate receiving plate 4b is penetrated through the central portion of the plate receiving plate 4b.
8 and the stopper 53 that is screwed perpendicularly to the upper surface of the support member 46 includes the stopper 55 and the first stopper 51 described above.
In cooperation with a to c, the descent of the weighing pan 10 is suppressed at a constant level. The stopper 53 is composed of a shaft-shaped screw and a nut like the second stopper 52 described above, and the lower end of the shaft-shaped screw projecting to the lower side of the support member 46 serves as the base 9 side member of the upper pressing plate 9d. It is configured to abut the upper surface. Since the stopper 53 is located at the center of the weighing pan 10, the position on which the normal article is placed and the position for receiving the overload at the time of overload coincide with each other, and it is possible to reduce the degree of occurrence of the rotation moment. If the above-mentioned first stoppers 51a to 51c are not provided, it is possible to reduce the generation of the rotation moment with respect to the low weighing load cell 3 only by the stopper 53. The stopper 55 is composed of an on-axis screw and a nut, and is provided at two lower portions of the connecting body 43 so as to come into contact with the upper surface of the box member 9b. This reduces the burden on each stopper.

Stoppers 54 provided at the four corners of the base 9
Limits the inclination of the base 9 to suppress the inclination of the high weighing load cell 2. The lower ends of the shaft-shaped screws protruding from the lower surfaces of the four corners of the base plate 9a are provided at the four corners of the lower case 1a. It is adjusted to a position that is a predetermined height above the upper surface of the receiving plate 1e. When the base 9 is tilted, the stopper 54 contacts the upper surface of the receiving plate 1e and prevents the base 9 from tilting any further.

The stopper 56 provided at the position corresponding to the low-weighing load cell 3 emphasis side 3b of the upper holding plate 9d of the base 9 is caused by the reaction when the emphasis side 3b of the low-weighing load cell 3 is impacted by an overload. , The critical side 3b is restricted from rising beyond the allowable range (FIG. 1). The stopper 56 is adjusted so that the lower end of the shaft-shaped screw threadedly passed through one side of the upper pressing plate 9d is projected to a position just before the upper surface of the connecting member 47, and the weight side 3b of the low weighing load cell 3 is adjusted. Comes into contact with the upper surface of the connecting member 47 when it rises due to the reaction of the overload.

On one side of the substrate 1c laid in the lower case 1a, a receiving plate 1f bent in a substantially L-shaped cross section is provided.
A stopper 57 is threaded vertically downward through the upper surface of the receiving plate 1f. The stopper 57 limits the rise of the weight side 2b beyond the permissible range due to the reaction when the weight side 2b of the high weighing load cell 2 is subjected to a shocking overload (FIGS. 1 and 6). . The stopper 57 is a state in which the lower end of an axial screw threadedly penetrated through the upper surface of the receiving plate 1f is projected to a position just before the upper surface of the tip of the extending plate 9c sandwiched between the load cells 2 and 3. The high weight load cell 2 comes into contact with the upper surface of the receiving plate 1f when the weight side 2b of the high weighing load cell 2 rises due to the reaction of overload.

Next, the operation of the multi-range load cell balance constructed as described above will be described. When a sample is placed on the weighing pan 10, the load lowers the weighing pan 10,
Two spring plates 42 of both Roberval mechanisms 41 of the buffer mechanism 4
Elastically deforms while maintaining parallelism.
The key side 41b is pushed down vertically. Then, the elastic deformation of the Roberval mechanism 41 absorbs the impact force when the weighing object is placed on the weighing pan 10, and the load is flexibly loaded on the weight side 3b of the low weighing load cell 3 and further on the high weighing load cell 2 as well.
Is transmitted to the emphasis side 2b of the. Since the Roberval mechanism 41 has a characteristic of elastically deforming in the vertical direction while keeping the emphasis side 4b vertical, the dish receiving plate 4b and the weighing dish 10 supported by the support member 46 are accurately moved up and down along the vertical track. It is possible. In addition, the Roberval mechanism 41
Due to the elastic deformation of the weighing plate 10, the weighing pan 10 continuously oscillates in the vertical direction, but due to the frictional resistance generated when the tip end of the friction spring plate 45 of the Roberval mechanism 41 rubs against the spring plate 42, the oscillation is caused. It decays quickly.

As described above, when the weighing object placed on the weighing pan 10 is 1 kg or less, this load is calculated based on the strain amount of the low weighing load cell 3, and the main body case 1
The weight is displayed on the front display unit 1j. In addition, when the load is 1 kg or more, it is calculated based on the strain amount of the high weighing load cell 2 and is similarly displayed on the display unit 1j. Further, when a heavy object that greatly exceeds the weighing capacity of the low weighing load cell 3 is placed on the weighing pan 10 so as to be dropped, the weighing pan 10 is shockedly lowered.

At this time, the impact force applied to the weighing pan 10 is temporarily absorbed and relaxed by the buffer mechanism 4. Further, when the inertial force due to the load is large, the first stopper 51c first comes into contact with the rubber plate 10a on the lower surface of the weighing pan 10, and then the remaining first stoppers 51a and 51b directly contact the lower surface of the weighing pan 10. The weighing pan 10 that touches and descends is received from below. In addition, the stopper 53 provided on the support member 46
Simultaneously with the abutment of the first stoppers 51a to 51c, the abutment also comes into contact with the upper pressing plate 9d to receive the load of the weighing pan 10. When the weighing pan 10 is supported from below by the first stoppers 51 to c, the pan receiving plate 4b that continues to descend due to inertia causes the weighing pan 1 to move.
Separate from the bottom surface of 0. Then, only the inertial force of the pan receiving plate 4b and the buffer mechanism 4 which descend due to inertia is applied to the weight side 3b of the low weighing load cell 3.

In the above process, the low-loading load cell 3 on the important side 3
When a high load is applied to b, the second stopper 52 abuts against the base 9 which is the member 3b on the weight side 3b of the low weighing load cell 3, and the downward inertial force applied to the weight 3b is replaced by the low weighing load cell 3. The load cell 3 is prevented from being damaged. As described above, the inertia caused by the heavy object shock-loaded on the weighing pan 10 is adjusted by the first and second stoppers 51a to 51c.
By 52, by absorbing in two stages, it is possible to effectively prevent damage to the low weighing load cell 3. But,
When a high inertial force other than common sense is generated due to an operator's mistake and the weight side 2b of the high weighing load cell 2 is pushed down beyond the allowable range, the weight side of the high weighing load cell 2 is stopped by the stopper 58 provided in the lower case 1c. The load cell 3 is abutted from below against 2b to avoid damage to the load cell 3. Further, when both load cells 2 and 3 are lifted by the reaction due to the high inertial force, the stoppers 57 and 56 contact from above to prevent damage.

In the above-mentioned embodiment, the pan receiving plate 4b and the weighing pan 10 are separable from each other.
The 0s may be combined together so as not to separate. In this case, even if the first stopper abuts, the weighing pan 10 on which the weighing object is placed and the pan receiving plate 4b are integrally received by the first stopper, but the inertia force is generated by the first stopper and the second stopper. The effect of reducing in two steps is obtained as in the above-mentioned embodiment.

Although the two-stage load cell scale is used in the above embodiment, the same effect can be obtained even if the load cell has only one stage or three or more stages. Further, although the buffer mechanism 4a is implemented by the Roberval mechanism, even if the buffer mechanism 4a is buffered by a cushioning material such as rubber instead of this, the inertial force is reduced by the first stopper and only the remaining inertial force is reduced by the second stopper. The action and effect of receiving the same can be similarly obtained. Further, although the first stopper is the stopper 51, the stoppers 53 and 55 have the same effect and may be the first stopper. Further, the stopper position is not limited to the position of the above embodiment, as long as the stopper position is at a position where the same operation is performed. The number of stoppers can be freely increased or decreased depending on the strength of each constituent member, for example, the weighing scale 10, the base 9, each stopper or the like.

[0038]

EFFECTS OF THE INVENTION Since the present invention is constructed as described above, even when a weighing object that exceeds the weighing capacity is placed on the weighing pan and the weighing pan is shockedly lowered, the first stopper is After contacting a member on the weighing pan side of the buffer mechanism of the pan receiving part with a large stroke so that the impact at that time is not transmitted to the low weighing load cell and most of the inertial force is reduced, the second stopper is further It completely absorbs the inertial force that remains by abutting on the weight side of the low weighing load cell, thus absorbing the inertia of the heavy object in two stages, reducing the impact of the second stopper, and effectively preventing damage to the low weighing load cell. be able to.

Further, in the case where the weighing pan and the pan receiving portion for receiving the weighing pan from below are separable, when the weighing pan is pushed down below a predetermined level by placing a heavy object, the first By supporting the weighing pan by bringing the stopper into contact with the weighing pan from below, the descending pan receiving portion can be separated from the weighing pan, and the inertial force corresponding to the heavy object placed on the weighing pan can be reduced. Therefore, it is possible to more effectively reduce the inertial force that is applied to the low weighing load cell on the priority side and is received by the second stopper.

Further, in the case where the buffer mechanism of the dish receiving portion is constituted by the Roberval mechanism, the first dish can be supported so that the weighing dish can be vertically lowered / raised without tilting even under an unbalanced load. It is possible to accurately bring the dish receiving portion cushioning mechanism into contact with a member on the weighing dish side, and it is possible to favorably maintain the effect of reducing the inertial force by the first stopper.

[Brief description of drawings]

FIG. 1 is a sectional view taken along line I-I in FIG.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a plan view showing a balance of the present invention.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is an exploded perspective view showing a pan receiving portion and a weighing pan.

FIG. 6 is an exploded perspective view showing a base and a lower case portion.

FIG. 7 is a perspective view showing a multi-range load cell balance of the present invention.

[Explanation of symbols]

 2 ... High weighing load cell 2a ... fulcrum side 2b ... focus side 3 ... low weighing load cell 3a ... fulcrum side 3b ... focus side 4 ... dish tray 4b ... dish Support plate 4a ... Buffer mechanism 41 ... Roberval mechanism 10 ... Weighing pan 51a-c ... First stopper 52 ... Second stopper

Claims (3)

[Claims] 1. A high weighing load cell and a low weighing load cell are provided, and the fulcrum side of the high weighing load cell is attached and fixed to the main body member, and the fulcrum side of the low weighing load cell is fixedly supported on the emphasis side of the high weighing load cell. In the multi-range load cell scale, the dish receiving part is mounted and supported on the priority side of the low weighing load cell via a buffer mechanism that elastically receives a vertical load, and the weighing plate is supported horizontally by the dish receiving part. A first stopper that abuts a member on the weighing pan side of the cushioning mechanism and a second stopper abuts on a member of the low weighing load cell emphasis side of the cushioning mechanism when the weighing pan is pushed down below a predetermined level. A multi-range load cell scale characterized by having and. 2. The multi-range load cell balance according to claim 1, wherein the weighing pan and the pan receiving portion are configured to be separable from each other, and the first stopper abuts against the weighing pan from below. 3. The cushioning mechanism is constituted by a Roberval mechanism formed by arranging two elastic plate members horizontally and in parallel and connecting both ends of both elastic plate members. Multi-range load cell scale.