Patent Description:
A resolution when using a load cell scale to measure the weight of a weighted object is limited by a gravimetric sensor, more specifically, limited by a measurement range (maximum weight) of a load cell configuring the gravimetric sensor. In a general load cell scale, the gravimetric sensor has only one load cell. A tip end portion of the gravimetric sensor is connected to an upper beam thereof to receive a force from a weighing tray of the load cell scale, and a base end portion of the gravimetric sensor is connected to a lower beam thereof to be fixed to a base plate of the load cell scale. For example, an electronic scale having a weighting of five kilograms (kg) generally has the resolution less than <NUM> gram (g). On the other hand, with respect to an electronic scale having a resolution of about <NUM> grams, the weighting thereof is generally suitable for weighting a weighted object of several hundred grams. In other words, the gravimetric sensor in a conventional load cell scale can only weight the weighted obj ect with a single resolution.

In Patent Document <NUM>, a double-weighting electronic scale configured from two gravimetric sensors having different resolutions is disclosed. According to the electronic scale disclosed in Patent Document <NUM>, in a case when a weighted object whose weight is less than a predetermined weight, the weighted object is only supported by the gravimetric sensor having a smaller weighting so as to measure the weight of the weighted object. On the other hand, in a case when the weighted object whose weight is more than the predetermined weight, the weighted object is supported by both of the gravimetric sensors so as to measure the weight of the weighted object.

However, according to the electronic scale disclosed in Patent Document <NUM>, there is no mechanism configured to protect the two gravimetric sensors by limiting the deformation of the two gravimetric sensors. More specifically, according to the electronic scale disclosed in Patent Document <NUM>, in the case of placing the weighted object whose weight is more than the weighting of the two gravimetric sensors on the weighting tray, or an intentioned impact is applied on the weighting tray, there is a possibility that permanent strain occurs in the two gravimetric sensors since the maximum deflection of each of the two weight sensors due to the force beyond the maximum deflection of each of the two weight sensors. The scale disclosed in document <CIT> has the same drawbacks.

According to the electronic scale disclosed in Patent Document <NUM>, since the gravimetric sensor whose weighting is larger is supported by a spring which does not have rigidity, for example, in a case when a <NUM> weighted object is placed on the weighting tray, the weighting process becomes unstable due to the vibration of the spring. Similarly, since a criterion for switching the two gravimetric sensors having different weightings is determined only by an elastic force of the spring, there is a possibility that the switching of the two gravimetric sensors is not correctly performed. Accordingly, there is a problem that according to the electronic scale disclosed in Patent Document <NUM>, the weighting result may be incorrect and it is not suitable for being used in a commercial environment due to a short service life.

The present invention is made in consideration of the foregoing circumstance, and an object of the present invention is to provide a load cell configured to be able to restrict the deformation occurring in the load cell even if in a case when a load exceeding the weighting is applied thereto, and a load cell scale having the load cell. Also, the present invention is made to achieve an obj ect to provide a load cell scale configured to have a plurality of load cells having different weightings so as to switch among the different weightings and perform the weighting of the weighted object correctly.

The present invention is directed to a load cell scale as defined in the appended claims. The load cell scale includes a load cell part formed in a columnar shape, the load cell part having a upper surface extending along a longitudinal axis and a lateral surface intersecting with the upper surface, and a stopper part configured to restrict deformation occurring in the load cell due to a load exceeding a predetermined value and applied to the load cell, wherein the load cell part has a strain portion capable of elastically deforming and the strain portion penetrates the load cell part from the lateral surface in a short direction orthogonal to the longitudinal direction, and wherein the stopper portion is provided to be connected to the lateral surface of the load cell part.

The stopper part is a plate-shaped member formed to extend along the longitudinal axis, and the stopper part has a fixing-end portion fixed to the lateral surface of the load cell and a free-end portion separating from the fixing-end portion along the longitudinal axis, the free-end portion being configured to restrict the elastic deformation of the load cell part due to the load in a state when the fixing-end portion is fixed to the lateral surface. When the dimensions of the stopper part in a height direction orthogonal to the upper surface is defined as a width of the stopper part, the stopper part may have a first width at the fixing-end portion and a second width in a range where the strain portion is formed along the longitudinal axis, and the first width of the stopper part is larger than the second width of the stopper part.

The fixing-end portion of the stopper part may have a third width between the first width and the second width.

The load cell part may have a position-restriction member formed to extend from the lateral surface in the short direction, the stopper part may have a position-restriction hole formed in the free-end portion and having a width suitable for the position-restriction member to enter, wherein when the load less than the predetermined value is applied to the load cell part, the position-restriction member may be at a position movable into the position-restriction hole, and when the load equal to or larger than the predetermined value is applied to the load cell part, the position-restriction member may be engaged with the position-restriction hole.

The stopper part may have a position-restriction tank configured to restrict an operation of the free-end portion, and the free-end portion may be in the position-restriction tank in the height direction.

An engaging hole for connecting the stopper part may be formed in the lateral surface of the load cell part, the stopper part may have an engaging member at the fixing-end portion that is capable of engaging with the engaging hole, and the stopper part may be connected to the lateral surface of the load cell part by engaging the engaging member with the engaging hole.

The lateral surface of the load cell part may have a groove formed along the direction of the longitudinal axis and in a range where the strain portion is formed in the height direction orthogonal to the upper surface, and the stopper part may be disposed to be accommodated in the groove.

The load cell scale may further have an intermediate member formed to be sandwiched between the load cell part and a portion where the stopper part is fixed to the lateral surface along the short direction.

The load cell part may be configured by configuring a first load cell having a first weighting and a second load cell having a second weighting that is larger than the first weighting along the direction of the longitudinal axis or the height direction, the stopper part may have a first stopper and a second stopper corresponding to the first load cell and the second load cell respectively, and the fixing-end portion of the first stopper and the free-end portion of the second stopper is adjacent to each other.

A first length of the first stopper along the direction of the longitudinal axis of the first stopper may be different from a second length of the second stopper along the direction of the longitudinal axis of the second stopper.

When the load being less than the first weighting is applied to the first load cell, the elastic deformation may occur in the first load cell and the free-end portion of the first stopper may move with respect to the first load cell, and when the load being larger than the first weighting and less than the second weighting is applied to the first load cell, the elastic deformation may occur in the second load cell and the free-end portion of the second stopper may move with respect to the second load cell in a state in which the first stopper and the first load cell are engaged with each other.

The first load cell and the second load cell may have a first position-restriction member and a second position-restriction member respectively, the first stopper and the second stopper may have a first position-restriction hole and a second position-restriction hole formed in the free-end portions of the first stopper and the second stopper and having widths suitable for the first position-restriction member and the second position-restriction member to enter respectively, when the load less than the first weighting is applied to the load cell part, the first position-restriction member and the second position-restriction member may be movable in the first position-restriction hole and the second position-restriction hole respectively, when the load equal to or larger than the first weighting and less than the second weighting is applied to the load cell part, the first position-restriction member may be engaged with the first position-restriction hole and the second position-restriction member may be movable in the second position-restriction hole, and when the load larger than the second weighting is applied to the load cell part, the first position-restriction member and the second position-restriction member may engage with the first position-restriction hole and the second position-restriction hole respectively.

The load cell scale may further include a protection member fixed to the first load cell, and when the load larger than the first weighting is applied, the first load cell and the protection member may operate simultaneously to prevent the deformation occurring in the first load cell.

The second topper of the second load cell may have a third width between the first width and the second width in the fixing-end portion.

According to the load cell disclosed in the above-described aspects, even if in a case when the load exceeding the weighting is applied, it is possible to restrict the deformation occurring in the load. Also, according to the above-described aspects, in the load cell scale configured from the plurality of load cells having different weightings, it is possible to accurately switch the weightings and measure the weighting of the weighted object.

A load cell <NUM> and a load cell scale <NUM> configured by having the load cell <NUM> according to a first embodiment of the invention will be described with reference to the enclosed <FIG>. <FIG> is a perspective view showing the load cell <NUM> according to the present embodiment. <FIG> is a front view showing the configuration of the load cell <NUM>. <FIG> is a side view showing the configuration of the load cell. In the present embodiment, a direction along the Y-axis shown in <FIG> is defined as a direction of a longitudinal axis of the load cell <NUM>, a direction along the X-axis that is orthogonal to the direction along the Y-axis is defined as a short direction of the load cell <NUM>, and a direction orthogonal to a plane defined by the X-axis and the Y-axis is defined as a height direction. Also, according to the present embodiment, as shown in <FIG>, an end portion at the left side of the load cell <NUM> along the direction along the Y-axis is defined as a tip end, and an end portion at the right side of the load cell <NUM> is defined as a base end.

As shown in <FIG>, the load cell <NUM> has a columnar body <NUM> having a square pole shape formed to extend in the direction of the longitudinal axis (that is, in the direction of Y-axis) and a stopper member <NUM> connected to the columnar body <NUM>. For example, the columnar body <NUM> and the stopper member <NUM> of the load cell <NUM> are members having rigidity and being formed from various metal materials. As shown in <FIG>, the columnar body <NUM> is formed to extend in the direction of the longitudinal axis L (that is, in the direction of Y-axis).

As shown in <FIG>, the columnar body <NUM> has an upper surface <NUM> formed to extend along the longitudinal axis L, a lateral surface <NUM> formed to be orthogonal to the upper surface <NUM>, and an end surface <NUM> orthogonal to both of the upper surface <NUM> and the lateral surface <NUM>. According to the present embodiment, the upper surface <NUM> is formed in a plane defined by the X-axis and the Y-axis, the lateral surface <NUM> is formed in a plane defined by the Y-axis and the Z-axis, and the end surface <NUM> is formed in a plane defined by the X-axis and the Z-axis.

As shown in <FIG>, a penetration hole <NUM> is formed by cutting off part of the columnar body <NUM> inwardly from the lateral surface <NUM> along the short direction of the columnar body <NUM> (that is, along the direction of X-axis). As shown in <FIG>, according to the present embodiment, in a case of viewing the penetration hole <NUM> formed in the columnar body <NUM> from the direction of X-axis, an internal circumferential surface of the penetration hole <NUM> has a shape formed by arranging two substantial semicircular shape along the longitudinal axis L. The internal surface of the penetration hole <NUM> is symmetrical with respect to the longitudinal axis L as a symmetry axis. According to the present embodiment, for example, sensors configured to transform a deformation volume or a stress in response to the deformation of the columnar body <NUM> into electrical signals are disposed in the internal circumferential surface of the penetration hole <NUM>. Accordingly, when a weighted object (see <FIG>) having a weight M is placed on the load cell scale <NUM> so as to perform a measurement, the weight of the weighted object is applied to the load cell <NUM> as a load such that micro deformation occurring in the columnar body <NUM> is transformed into the electrical signals by the sensors disposed in the internal circumferential surface of the penetration hole <NUM>.

The load cell scale <NUM> is configured to measure the weight (mass) of the weighted obj ect by detecting the electrical signals. Generally, as shown in <FIG>, a width W1 of the penetration hole <NUM> along the direction of the longitudinal axis may be determined in correspondence with the weight of the weighted object. In other words, for example, in a case in which a percentage of the width W1 with respect to the width of the columnar body <NUM> in the direction of the longitudinal axis is relatively high, the deformation volume of the columnar body may be large so as to perform a weighting with a low weighting. On the other hand, in a case in which a percentage of the width W1 with respect to the width of the columnar body <NUM> in the direction of the longitudinal axis is relatively low, the deformation volume of the columnar body may be small so as to perform a weighting with a high weighting. According to the present embodiment, the part of the load cell <NUM> where the penetration hole <NUM> is formed functions as a strain portion being elastic deformable. In other words, it is possible to measure the weight M of the weighted object by detecting and measuring the elastic deformation volume occurring in the penetration hole <NUM> of the load cell <NUM>.

In the load cell <NUM>, a groove portion <NUM> is formed by cutting off part of the columnar body <NUM> from the lateral surface <NUM> inwardly along the direction of the longitudinal axis (that is, the Y-axis direction) of the columnar body <NUM>. According to the present embodiment, as shown in <FIG>, the groove portion <NUM> has a depth W2 in the short direction of the columnar body <NUM> which is suitable to accommodate at least part of the stopper member200. According to the present embodiment, it is preferable to set the sum of the width of the stopper member <NUM> and the width of an intermediate member <NUM> described below to be substantially the same as the depth W2 of the groove portion <NUM>; however, the present embodiment is not limited thereto.

Also, as shown in <FIG>, the groove portion <NUM> has a uniform width H5 in the height direction (that is, the Z-axis direction) of the load cell <NUM>. According to the present embodiment, the width H5 of the groove portion <NUM> is at least larger than a width H4 of a tip end portion (free-end portion) of the stopper member <NUM> described below.

As shown in <FIG>, according to the present embodiment, the stopper member <NUM> is connected and fixed to the columnar body <NUM> in a state in which the stopper member <NUM> is disposed in the groove portion <NUM> formed in the columnar body <NUM>. As shown in <FIG>, the stopper member <NUM> has a substantial I shape. In the height direction of the load cell <NUM>, the stopper member <NUM> has a width H1 at the base end portion (fixing-end portion), a width H2 of a waist portion <NUM> formed in the range where the penetration hole <NUM> is formed, a width H3 of a step portion <NUM> formed at the base end portion, and a width H4 at the tip end portion (free-end portion). According to the present embodiment, in order to make the description easy, an example that the width H1 and the width H4 of the stopper member <NUM> are substantially the same will be described; however, the present embodiment is not limited thereto. For example, the width H1 at the base end portion of the stopper member <NUM> may be substantially the same with the width H5 of the groove portion <NUM>. In the stopper member <NUM>, the width H1 of the base end portion is larger than the width H2 of the waist portion <NUM>. In the stopper member <NUM>, in the range where the penetration hole <NUM> of the columnar body <NUM> is formed, the width H2 of the waist portion <NUM> is smaller than the width of the penetration hole <NUM>. Accordingly, even in a case in which the stopper member <NUM> is connected and fixed to the columnar body <NUM>, it is possible to adjust the weighting (for example, the maximum weighting) that can be measured by the load cell <NUM> by inserting a tool into a gap between the stopper member <NUM> and the internal circumferential surface of the penetration hole <NUM> so as to process the internal circumferential surface of the penetration hole <NUM> into the substantial semicircular shape. Furthermore, it is possible to adjust minute deficiencies such as four-corner errors by processing (perform a cutting processing) the internal circumferential surface of the penetration hole <NUM> using a file. Such a processing is an essential processing during the procedures to manufacture the load cell and the processing has to be performed in a state in which the stopper member <NUM> is attached to the load cell such that it is possible to avoid the attachment and detachment of the stopper member <NUM> every time when the adjustment is performed so as to save time and labor by providing the waist portion <NUM>.

In the stopper member <NUM>, the width H4 at the tip end portion (free-end portion) is smaller than the width H5 of the groove portion <NUM>. Accordingly, in a case in which the weighted object is not disposed on the load cell scale <NUM>, the tip end portion of the stopper member <NUM> is separated from the internal circumferential surface for a predetermined interval in the groove portion <NUM>. When the weighted object is disposed on the load cell scale <NUM>, the load due to the weight M of the weighted object applies on the load cell <NUM> such that elastic deformation occurs across the whole length of the columnar body <NUM> along the direction of the longitudinal axis. However, even in this state, in the columnar body <NUM>, the width H5 of the groove portion <NUM> is still maintained across the whole length of the columnar body <NUM>. In other words, a downward displacement amount along the height direction of the load cell <NUM> occurring at the tip end side of the columnar body <NUM>, particularly in the structure in the penetration hole (strain portion) <NUM> and in the vicinity thereof is different from the downward displacement amount along the height direction of the load cell <NUM> occurring at the base end side of the columnar body <NUM>, in other words, in the structure connected and fixed to the fixing-end portion of the stopper member <NUM>. In the columnar body <NUM>, since the displacement amount at the tip end side where the load is directly applied is larger than the displacement amount at the base end side, in the penetration hole <NUM> formed at the tip end side of the columnar body <NUM> and the structure in the vicinity thereof, the gap between the stopper member <NUM> and the internal circumferential surface of the groove portion <NUM> of the columnar body <NUM> becomes smaller following the increase of the weight M of the weighted object disposed on the load cell <NUM> such that the internal circumferential surface of the groove portion <NUM> approaches the free-end portion formed at the tip end side of the stopper member <NUM>. According to the present embodiment, when the weight M of the weighted member increases to be substantially the same with the maximum weighting of the load cell <NUM>, the columnar body <NUM> and the stopper member <NUM> becomes an integrated configuration since the free-end portion of the stopper member <NUM> almostly contacts with the internal circumferential surface of the groove portion <NUM>.

According to the present embodiment, when the columnar body <NUM> and the stopper member <NUM> becomes to the integrated configuration, there is no further deformation occurring in the penetration hole <NUM> even if the load (the weight M of the weighted object) applied to the load cell further increases. In other words, even if the weighted object having the weight larger than the maximum weighting of the load cell <NUM> is disposed on the load cell <NUM>, there is no deformation exceeding an elastic deformation limit of the load cell <NUM> occurring in the load cell <NUM>. In other words, due to the configuration of disposing the free-end portion of the stopper member <NUM> in the groove portion <NUM>, in the case of applying the load larger than the maximum weighting of the load cell <NUM> on the load cell <NUM>, it is possible to avoid the reasons a permanent strain and a fatigue breakdown in the penetration hole (strain portion) <NUM> of the columnar body <NUM> is introduced.

Accordingly, for example, it is possible to suitably determine the width H4 of the free-end portion formed at the tip end portion of the stopper member <NUM> by measuring a maximum strain amount of the columnar body <NUM> when the load equivalent to the maximum weighting of the load cell <NUM> is applied to the load cell <NUM> and the width H5 of the groove portion <NUM> at the time.

As shown in <FIG>, a step portion <NUM> having the width H3 smaller than the width H1 is formed at the tip end side in the base end portion of the stopper member <NUM>. The length of the step portion <NUM> along the direction of the longitudinal axis of the load cell <NUM> may be suitably determined as required.

As shown in <FIG>, the step portion <NUM> is configured to secure a predetermined clearance between the base end portion of the stopper member <NUM> and the internal circumferential surface of the groove portion <NUM> in the Z-axis direction. More specifically, for example, in a case in which the step portion <NUM> is not provided in the base end portion of the stopper member <NUM>, due to tolerance during the manufacturing of the member and the like, before the load of the weighted object is applied on the load cell <NUM>, there is possibility that the base end portion of the stopper <NUM> unintentionally comes in contact with the internal circumferential surface of the groove portion <NUM> such that the base end portion of the stopper <NUM> and the internal circumferential surface of the groove portion <NUM> press each other. In this case, even if the weighted object is disposed on the load cell <NUM>, there is possibility that the weight M of the weighted object is not correctly reflected by the detected deformation amount generated in the penetration hole (strain portion) <NUM> of the columnar body <NUM>.

On the other hand, according to the present embodiment, it is possible to prevent the base end portion of the stopper member <NUM> and the internal circumferential surface of the groove portion <NUM> from unintentionally contacting with each other. Accordingly, when the weighted object is disposed on the load cell <NUM>, the deformation amount of the strain portion of the columnar body <NUM> may be corrected recognized. Also, since the step portion <NUM> is formed in only part of the base end portion of the stopper member <NUM>, it is possible to retain the rigidity of the stopper member <NUM>.

As shown in <FIG> and <FIG>, in the short direction (X-axis direction) of the load cell <NUM>, a plate-shaped intermediate member <NUM> is provided to be sandwiched between the base end portion of the stopper member <NUM> and the columnar body <NUM>. The intermediate member <NUM> is a plate-shaped member having rigidity and a thickness about several millimeters. As shown in <FIG>, according to the present embodiment, an example that the intermediate member <NUM> has a substantial same shape and area with the base end portion of the stopper member <NUM> is described, the present embodiment is not limited thereto. More specifically, due to the intermediate member <NUM> disclosed in the present embodiment, the base end portion of the stopper member <NUM> and the groove portion <NUM> of the columnar body <NUM> are separated from each other in the short direction of the load cell <NUM> such that a separating state between the free-end portion formed at the tip end side of the stopper member <NUM> and the groove portion <NUM> is maintained. The intermediate portion <NUM> only has to be sandwiched and fixed between the base end portion of the stopper member <NUM> and the columnar body <NUM> in the short direction of the load cell <NUM>, and the shape and the dimension thereof is not particularly limited.

According to the present embodiment, the load cell <NUM> has the intermediate member <NUM> such that in the short direction of the load cell <NUM>, it is possible to prevent the free-end portion formed at the tip end side of the stopper member <NUM> from unintentionally contacting with the columnar body <NUM>. Accordingly, since the load cell <NUM> has the intermediate member <NUM>, it is possible to correctly determine the elastic deformation amount of the penetration hole (strainportion) <NUM> of the columnar body <NUM> when the weighted object is disposed on the load cell scale <NUM>.

As shown in <FIG>, in the load cell <NUM>, the base end portion of the columnar body <NUM>, the intermediate member <NUM>, and the fixing-end portion formed in the base end portion of the stopper member <NUM> are connected and fixed by a fixing mechanism <NUM>. According to the present embodiment, the fixing mechanism <NUM> has a threaded screw hole which is formed to penetrate the fixing-end portion of the stopper member <NUM> and the intermediate portion <NUM> and have a predetermined depth at the base end side of the columnar body <NUM>, and a screw being engageable with the threaded screw hole. Accordingly, at the time of assembling the load cell <NUM>, it is easy to adjust an engagement state of the columnar body <NUM>, the intermediate member <NUM>, and the stopper member <NUM> by operations of tightening the screw or loosening the screw only. More specifically, for example, a relative position of the free-end portion of the stopper member <NUM> with respect to the groove portion <NUM> may be adjusted by adjusting the tightening degree of the two screws.

According to the present embodiment, the method of connecting the columnar body <NUM>, the intermediate member <NUM>, and the stopper member <NUM> is not limited to the fixing mechanism <NUM>. For example, an amount of the threaded screw holes and the positions of the threaded screw holes in the fixing mechanism <NUM> may be suitably adjusted, and other engagement method besides the screw may be adopted. Also, for example, the stopper member <NUM>, the intermediate member <NUM>, and the columnar body <NUM> may be directly connected by methods such as the welding and the like.

As shown in <FIG>, the load cell <NUM> has a wiring hole <NUM> penetrating the base end side of the columnar body <NUM>, the intermediate member <NUM>, and the fixing-end portion of the stopper member <NUM>. The wiring hole <NUM> is suitably formed as desired and it not particularly limited. For example, the wiring hole <NUM> is provided for inserting wirings therethrough so as to transmit the signals detected by the sensors provided on the internal circumferential surface of the penetration hole <NUM> of the columnar body <NUM> or the necessary signals for controlling the load cell scale <NUM>. According to the present embodiment, since the wiring hole <NUM> is formed in a base-end fixing portion at the base end side of the stopper member <NUM>, that is, the wiring hole <NUM> is formed in a range where the rigidity is relatively large in the load cell <NUM> and at a position separated from the penetration hole <NUM> as the strain portion by a predetermined interval, it is possible to prevent the wirings passing through the wiring hole <NUM> from unintentionally contacting with the surrounding configurations so as to suppress the effect of the measurement of the deformation amount generated in the strain portion of the load cell <NUM> and improving the precision of the weighting result of the weighted object.

As shown in <FIG> and <FIG>, in the load cell <NUM>, two connection holes <NUM> are formed in the end surface <NUM> at the base end side thereof. The two connection holes <NUM> are formed to connect the load cell <NUM> to a lower support member <NUM> (see <FIG>). At the time of assembling the load cell scale <NUM>, the load cell <NUM> is fixed to a base plate <NUM> (see <FIG>) via the lower support member <NUM>. Furthermore, although it is not disclosed in figures, the connection hole <NUM> is also formed in the end surface at the tip end side of the load cell <NUM>. Accordingly, the load cell <NUM> is connected to a weighting tray <NUM> (see <FIG>) via an upper support member <NUM>.

As described above, at the time of assembling the load cell scale <NUM> according to the present embodiment, the load cell <NUM> is connected to the weighting tray <NUM> via the upper support member <NUM> and the load cell is supported by the base plate <NUM> via the lower support member <NUM>. The upper support member <NUM>, the lower support member <NUM>, the weighting tray <NUM>, and the base plate <NUM> may be configured by adopting various conventional configurations.

The load cell scale <NUM> according to the present embodiment has the above-described configurations so as to correctly measure the weight M of the weighted object that is smaller than the maximum weighting of the load cell <NUM>. On the other hand, in the case when the weighted object heavier than the maximum weighting of the load cell <NUM> is disposed on the weighting tray <NUM>, or an unintentional impact is applied on the weighting tray <NUM>, it is possible to avoid the permanent strain and malfunctions occurring in the load cell <NUM>.

More specifically, the load cell <NUM> according to the present embodiment has the stopper member <NUM>, wherein at least part of the stopper member <NUM> is accommodated in the groove portion <NUM> formed by cutting off part of the columnar body <NUM> inwardly from the lateral surface <NUM> of the columnar body <NUM> in the short direction. In the groove portion <NUM>, a tip-end free portion of the stopper member <NUM> is separated from the internal circumferential surface of the groove portion <NUM> by a predetermined interval such that when the weighted object is disposed on the weighting tray <NUM>, the tip-end free portion of the stopper member <NUM> relatively moves with respect to the internal circumferential surface of the groove portion <NUM>. In the case when the weighted object heavier than the maximum weighting of the load cell <NUM> is disposed on the weighting tray <NUM>, the tip-end free portion of the stopper member <NUM> contacts with the internal circumferential surface of the groove portion <NUM> such that the stopper member <NUM> and the columnar body <NUM> become an integrated configuration. In this state, the stopper member <NUM> may prevent unintentional deformation occurring in the penetration hole <NUM> configured as the strain portion of the columnar body <NUM>. The stopper member <NUM> is connected and fixed to the lateral surface <NUM> of the columnar body <NUM> so as to suppress the dimension of the load cell <NUM> in the height direction and it is effective for the thinning of the load cell scale <NUM>.

According to the present embodiment, the stopper member <NUM> has the step portion <NUM> formed in part of the fixing-end portion at the base end side. The load cell <NUM> has the intermediate member <NUM> configured to be sandwiched between the stopper member <NUM> and the columnar body <NUM> in the short direction. At the time of weighting the weighted object, the step portion <NUM> and the intermediate member <NUM> exclude other elements except the weight M of the weighted object that may affect the accuracy of measuring the deformation amount of the penetration hole <NUM> as the strain portion of the columnar body <NUM> due to the unintentional contact of the stopper member <NUM> and the columnar body <NUM>.

According to the present embodiment, the stopper member <NUM> has the waist portion <NUM> formed in the substantial I shape between the tip-end free portion and the base-end fixing portion. Accordingly, at the time of assembling the load cell <NUM>, even if in that state when the stopper member <NUM> is fixed to the columnar body <NUM>, in the range where the waist portion <NUM> is formed in the direction of the longitudinal axis, there is enough gap between the waist portion <NUM> and the penetration hole <NUM> for inserting the tool thereto to adjust the shape of the internal circumferential surface of the penetration hole <NUM>. Furthermore, as described above, in the load cell <NUM> according to the present embodiment, it is possible to adjust the engagement of the stopper member <NUM>, the intermediate member <NUM>, and the columnar body <NUM> by adjusting the screws provided in the fixing mechanism <NUM>.

Accordingly, at the time of assembling the load cell scale <NUM> according to the present embodiment, or at the time of performing maintenance to the load cell scale <NUM>, it is possible to adjust the strain portion of the load cell <NUM> by easy operations. In other words, it is possible to reduce the manufacturing cost and the maintenance cost with respect to the load cell <NUM> and the load cell scale <NUM> having the load cell <NUM> according to the present embodiment.

Hereinafter, a configuration of a load cell 10A according to a first modification example of the present embodiment will be described with reference to <FIG>. The same configurations with the load cell <NUM> according to the above-described first embodiment will be given to the same reference signs and the description will be omitted, and configurations different from the above-described embodiment will be described.

As shown in <FIG>, the load cell 10A according to the present modification example is different from the load cell <NUM> according to the above-described first embodiment in that the groove portion is not formed in a columnar body 100A and a stopper member 200A is formed in a substantial T shape.

More specifically, as shown in <FIG>, at a more tip end side than the penetration hole <NUM> of the columnar body 100A of the load cell 10A according to the present embodiment, a protrusion <NUM> protruding outwardly from the lateral surface <NUM> in the short direction is formed. On the other hand, the stopper member 200A of the load cell 10A according to the present embodiment has the base-end fixing portion formed to have the width H1 in the height direction of the load cell 10A and the waist portion <NUM> having the width H2 smaller than the width H1. A penetration hole <NUM> having an inner diameter (width) suitable for the protrusion <NUM> to enter is formed at the tip end side of the waist portion <NUM> of the stopper member 200A.

In the direction of the longitudinal axis of the load cell 10A, a step portion <NUM> is formed between the base-end fixing portion of the stopper member 200A and the waist portion <NUM>. According to the present modification example, for example, the stopper member 200A may be formed by bending a plate-shaped member formed from the metal material having rigidity at the step portion <NUM>.

Similar to the load cell <NUM> according to the above-described first embodiment, the base-end fixing portion of the load cell 10A according to the present embodiment is fixed to the columnar body 100A by the fixing mechanism <NUM>. On the other hand, since the step portion <NUM> is formed in the stopper member 200A, the waist portion <NUM> and the tip-end free portion of the stopper member 200Aare separated from the lateral surface of the columnar body 100A by a predetermined interval in the short direction of the load cell 10A. That is, in the load cell 10A according to the present modification example, it is not necessary to provide the intermediate member <NUM> between the base-end fixing portion of the stopper member 200A and the columnar body 100A.

However, the configuration of the load cell 10A according to the present modification example is not limited thereto. For example, the step portion <NUM> may not formed in the stopper member 200A of the load cell 10A according to the present modification example, and the intermediate member <NUM> may be provided between the base-end fixing portion of the stopper member 200A and the lateral surface of the columnar body 100A.

The load cell 10A according to the present modification example has the above-described configuration such that the same effect with the load cell according to the above-described first embodiment is achieved. More specifically, according to the load cell scale having the load cell 10A according to the present modification example, when the weighted object with a weight less than the maximum weighting of the load cell 10A is disposed on the weighting tray to be weighted, due to the elastic deformation occurring in the strain portion (penetration hole <NUM>) of the columnar body 100A of the load cell 10A, the protrusion <NUM> formed in the columnar body 100A relatively moves in the penetration hole <NUM> of the stopper member 200A. Accordingly, similar to the load cell <NUM> according to the above-described first embodiment, it is possible to measure the weight M of the weighted object by detecting the elastic deformation amount of the strain portion.

On the other hand, when the weighted object having a weight larger than the maximum weighing scale of the load cell 10A is disposed on the weighting tray, the protrusion <NUM> formed in the columnar body 100A contacts the internal circumferential surface of the penetration hole <NUM> of the stopper member 200A and the columnar body 100A and the stopper member 200A become an integrated configuration so as to restrict the further deformation of the strain portion (see <FIG>). Accordingly, according to the load cell 10A according to the present modification example, when the weighted object heavier than the maximum weighting is disposed on the weighting tray or the unintentionally impact is applied on the weighting tray, it is possible to avoid the permanent strain and malfunctions occurring in the load cell 10A.

Hereinafter, a configuration of a load cell 10B according to a second modification example of the present embodiment will be described with reference to <FIG>. The same configurations with the load cell <NUM> according to the above-described first embodiment will be given to the same reference signs and the description will be omitted, and configurations different from the above-described embodiment will be described.

As shown in <FIG>, the load cell 10B according to the present modification example is different from the load cell <NUM> according to the above-described first embodiment in that a stopper member 200B is formed in a substantial T shape and a first position-restriction member <NUM> is formed at the tip end side of the columnar body <NUM>.

The first position-restriction member <NUM> of the load cell 10B according to the present modification number is fixed to the tip end side of the columnar body 100by the fixing mechanism <NUM>. The first position-restriction member <NUM> has a position-restriction tank <NUM> that may cover at least part of the tip-end free portion of the stopper member 200B. In other words, at least part of the tip-end free portion of the stopper member 200B of the load cell 10B is accommodated in the position-restriction tank <NUM> formed in the first position-restriction member <NUM>. Also, in this state, the tip-end free portion of the stopper member 200B and the position-restriction tank <NUM> are separated by a predetermined interval in the height direction of the load cell 10B. The interval between the tip-end free portion of the stopper member 200B and the position-restriction tank <NUM> is suitably determined according to the elastic deformation amount of the strain portion (penetration hole <NUM>) corresponding to the maximum weighting of the load cell 10B.

According to the load cell 10B disclosed in the present modification example, when the weighted object having the weight less than the maximum weighting is disposed on the weighting tray, the elastic deformation occurs in the strain portion (penetration hole <NUM>) of the load cell 10B, and tip-end free portion of the stopper member 200B relatively moves with respect to the first position-restriction member <NUM> in the position-restriction tank <NUM>. In this case, since the tip-end free portion of the stopper member 200B does not contact with the internal surface of the position-restriction tank <NUM>, the elastic deformation of the strain portion of the load cell 10B is not restricted.

On the other hand, when the weighted object heavier than the maximum weighting is disposed on the weighting tray, the strain portion (penetration hole <NUM>) of the load cell 10B reaches the limitation of the elastic deformation and the tip-end free portion contacts with the internal surface of the position-restriction tank <NUM>. In this state, the stopper member 200B and the columnar body <NUM> becomes the integrated configuration. Accordingly, it is possible to prevent the deformation exceeding the elastic deformation limit occurring in the strain portion of the columnar body <NUM>. According to the load cell 10B according to the present modification, when the weighted obj ect heavier than the maximum weighting is disposed on the weighting tray or the unintentionally impact is applied on the weighting tray, it is possible to avoid the permanent strain and the malfunctions occurring in the load cell 10B.

The configurations of the load cells according to the first embodiment and two modification examples of the first embodiment of the present invention are described. The load cell according to the present embodiment and the modification examples only have a single strain portion. Accordingly, as shown in <FIG>, the load cell scale <NUM> having the single weighting is configured by attaching the upper support member <NUM>, the lower support member <NUM>, the weighting tray <NUM>, and the base plate <NUM> having the conventional configurations to the load cell according to the present embodiment and the modification examples. According to the load cell scale <NUM> according to the present embodiment and the modification examples, when the weighted object heavier than the maximum weighting is disposed on the weighting tray or the unintentionally impact is applied on the weighting tray, it is possible to avoid the permanent strain and malfunctions occurring in the load cell. Also, according to the load cell scale according to the present embodiment and the modification examples, since the stopper member is disposed at the lateral surface of the load cell, it is possible to make the load cell scale <NUM> to be thin. Furthermore, according to the load cell scale <NUM> according to the present embodiment and the modification examples, since the strain portion can be adjusted by easy operations, the assembling cost and the maintenance cost of the load cell scale <NUM> can be reduced.

Hereinafter, the load cell <NUM> and the load cell scale <NUM> having the load cell <NUM> according to a second embodiment of the present invention will be described with reference to <FIG>. The load cell <NUM> according to the present embodiment has a tip-end load cell unit <NUM> and a base-end load cell unit <NUM> which are integrated in the direction of the longitudinal axis. More specifically, as shown in <FIG>, in the direction of the longitudinal axis, the load cell unit <NUM> according to the present embodiment is configured to have a base-end fixing portion <NUM> of the tip-end load cell unit <NUM> and a tip-end free portion <NUM> of the base-end load cell unit <NUM> to be adjacent with each other. Accordingly, the tip end portion of the tip-end load cell unit <NUM> is the tip end portion of the whole load cell <NUM>, and the base end portion of the base-end load cell unit <NUM> is the base end portion of the whole load cell <NUM>.

According to the present embodiment, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> have the substantially same configurations with the load cell <NUM> according to the above-described first embodiment. More specifically, each of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> is configured to have the stopper member <NUM> including the base-end fixing portion <NUM> and the tip-end free portion <NUM>. As shown in <FIG> and <FIG>, groove portions <NUM> configured to restrict the movement of the tip-end free portions <NUM> of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> are formed in the lateral surface of the columnar body <NUM> of the load cell <NUM> according to the present embodiment. According to the present embodiment, the stopper member <NUM> having the base-end fixing portion <NUM> and the tip-end free portion <NUM> is defined as a second position-restriction member <NUM>, and the groove portion <NUM> is defined as the first position-restriction member <NUM>.

In order to make the description to be easy, according to the present embodiment, the example in which the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> have the same configurationswillbedescribed, however, the present embodiment is not limited thereto. For example, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> may have different configurations. More specifically, for example, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> may be configured to suitably combine the configurations disclosed in the above-described first embodiments and the modification examples or adopt other conventional configurations.

As shown in <FIG>, according to the present embodiment, the penetration hole <NUM> as the strain portion is formed in each of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> of the load cell <NUM>. As shown in <FIG>, the width of the penetration hole <NUM> of the tip-end load cell unit <NUM> in the direction of the longitudinal axis is larger than the width of the penetration hole <NUM> of the base-end load cell unit <NUM>. Accordingly, in the load cell <NUM>, the maximum weighting M1 of the tip-end load cell unit <NUM> is smaller than the maximum weight ing M2 of the base-end load cell unit <NUM>. The maximum weighting of the whole load cell <NUM> is equal to the maximum weighting M2 of the base-end load cell unit <NUM>. In the load cell unit <NUM>, the tip-end load cell unit <NUM> may have a higher weighting accuracy than that of the base-end load cell unit <NUM>.

Accordingly, it is possible to configure a load cell scale having a maximum weighting larger than that of the load cell <NUM> according to the above-described first embodiment by adopting the load cell <NUM> according to the present embodiment. Furthermore, according to the load cell <NUM> disclosed in the present embodiment, as described below, in a case of weighting the weighted object lighter than the maximum weighting M1 of the tip-end load cell unit <NUM>, the tip-end load cell unit <NUM> having a relatively higher accuracy is used such that a weighting result with higher accuracy may be achieved.

As shown in <FIG> and <FIG>, in the load cell <NUM> according to the present embodiment, the intermediate member <NUM> is provided between the base-end fixing portion <NUM> and the groove portion <NUM> of each of the base-end load cell unit <NUM> and the tip-end load cell unit <NUM>. Accordingly, similar to the load cell according to the above-described first embodiment and the modification examples, the accuracy of the weighting results of the weighted object may be improved by preventing the stopper member <NUM> and the columnar body <NUM> from unintentionally contacting with each other. As shown in <FIG>, according to the present embodiment, the groove portion <NUM> in the columnar body <NUM> of the load cell <NUM> may be formed to have a depth substantially same with the sum of the thicknesses of the stopper member <NUM> and the intermediate member <NUM> in the short direction; however, the present embodiment is not limited thereto.

For example, as shown in <FIG>, in the load cell <NUM> of the load cell scale <NUM> according to the present embodiment, the intermediate member <NUM> may not be provided between the stopper member <NUM> and the columnar body <NUM>, and the stopper member <NUM> may have the step portion <NUM>.

As shown in <FIG>, the tip-end load cell unit <NUM> of the load cell <NUM> has a step portion <NUM> having the width H3 in the Z-axis direction and formed at the tip end side of the base-end fixing portion <NUM>, similar to the step portion <NUM> formed in the stopper member <NUM> of the load cell <NUM> according to the above-described first embodiment. Accordingly, according to the load cell <NUM> disclosed in the present embodiment, similar to the load cell <NUM> according to the above-described embodiment <NUM>, it is possible to realize both of the goals of correctly recognizing the deformation amount of the strain portion occurring in the tip-end load cell unit <NUM> and retaining the rigidity of the tip-end load cell unit <NUM>.

According to the present embodiment, in the load cell <NUM>, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> are integrated configured along the direction of the longitudinal axis. Accordingly, comparing with a case in which two load cell units are connected to configure a load cell, the load cell <NUM> according to the present embodiment can eliminate the assembly tolerances and the like during the procedures of connecting several load cell units so as to configure the load cell <NUM> with a higher assembly precision. Also, since it is not necessary to use a connection member for connecting the several load cell units, it is possible to reduce components, shorten the assembly procedures such that the load cell <NUM> can be manufactured at a lower cost.

Other configurations of the load cell <NUM> according to the present embodiment are the same with that of the load cell <NUM> according to the above-described first embodiment, therefore the description will be omitted. The load cell scale <NUM> (see <FIG>) according to the present embodiment can be configured by attaching the above-described lower support member <NUM>, the base plate <NUM>, the upper support member <NUM>, and the weighting tray <NUM> to the load cell <NUM> according to the present embodiment.

Hereinafter, operations of the load cell <NUM> and the load cell scale <NUM> having the above-described configurations will be described. More specifically, the operations of the load cell <NUM> according to the present embodiment will be described according to the relation of the weight M of the weighted obj ect, the maximum weighting M1 of the tip-end load cell unit <NUM> of the load cell <NUM>, and the maximum weighting M2 of the base-end cell unit <NUM>. As described above, in the load cell unit <NUM> according to the present embodiment, the maximum weighting M1 of the tip-end load cell unit <NUM> is smaller than the maximum weighting M2 of the base-end load cell unit <NUM>.

Firstly, a case in which the weight M of the weighted obj ect is less than the maximum weighting M1 of the tip-end load cell unit <NUM> will be described. In this case, when the weighted obj ect is disposed on the weighting tray of the load cell scale <NUM> having the load cell <NUM>, the weight M of the weighted object applies on the load cell <NUM> as the load. Since the weight M of the weighted object is less than the maximum weighting M1 of the tip-end load cell unit <NUM>, the elastic deformation occurs in the penetration hole <NUM> as the strain portion of the tip-end load cell unit <NUM>, however there is almost no elastic deformation occurring in the strain portion of the base-end load cell unit <NUM>. In other words, in this state, in the tip-end load cell unit <NUM>, the tip-end free portion <NUM> of the stopper member <NUM> is in the groove portion <NUM> and moves with respect to the internal surface of the groove portion <NUM>; however the tip-end free portion <NUM> does not contact with the internal surface of the groove portion <NUM>.

When the weighted object having the weight equal to the maximum weighting M1 of the tip-end load cell unit <NUM> is disposed on the weighting tray of the load cell scale <NUM>, due to the deformation of the penetration hole <NUM> as the strain portion, the tip-end free portion <NUM> of the stopper member <NUM> contacts with the internal surface of the groove portion <NUM>. In other words, in this state, the stopper member <NUM> (second position-restriction member <NUM>) and the groove portion <NUM> (first position-restriction member <NUM>) of the tip-end load cell unit <NUM> contact and engage with each other such that the tip-end load cell unit <NUM> and the columnar body <NUM> become the integrated configuration. In this state, the strain portion of the tip-end load cell unit <NUM> almost reaches the limit of the elastic deformation, however there is almost no elastic deformation occurring in the strain portion of the base-end load cell unit <NUM>.

Hereinafter, a case in which the weighted object having a weight larger than the maximum weighting M1 of the tip-end load cell unit <NUM> and less than the maximum weighting M2 of the base-end load cell unit <NUM> is disposed on the weighting tray of the load cell scale <NUM> will be described. In this case, as described above, the stopper member <NUM> of the tip-end load cell unit <NUM> and the columnar body <NUM> has become the integrated configuration such that the strain portion of the tip-end load cell unit <NUM> retains the maximum elastic deformation amount and no further deformation occurs therein. Accordingly, in the tip-end load cell unit <NUM>, it is possible to prevent the penetration <NUM> as the strain portion from further deforming exceeding the limit of the elastic deformation.

At this time, the weight M of the weighted object applies to the base-end load cell unit <NUM> as the load and the elastic deformation occurs in the penetration hole <NUM> as the strain portion in the base-end load cell unit <NUM>. Also, in this case, the tip-end cell unit <NUM> may be recognized as part of the base-end cell unit <NUM>. Similar to the case described above, it is possible to measure the weight M of the weighted object by detecting the signals indicating the elastic deformation amount of the penetration hole <NUM> as the strain portion of the base-end load cell unit <NUM>.

In a case in which the weighted object having the weight M equal to or larger than the maximum weighting M2 of the base-end load cell unit <NUM> is disposed on the load cell scale <NUM>, both of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> are in the state where the elastic deformation occurring therein reaches the limit amount. In this state, the stopper member <NUM> (second position-restricting member <NUM>) and the groove portion <NUM> (first position-restricting member <NUM>) of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> contact and engage with each other such that the tip-end load cell unit <NUM>, the base-end load cell unit <NUM>, and the columnar body <NUM> become the integrated configuration. Accordingly, according to the load cell <NUM> disclosed in the present embodiment, it is possible to prevent the deformation exceeding the limit of the elastic deformation and the malfunctions in the tip-end load cell unit <NUM> and the base-end load cell unit <NUM>.

According to the load cell <NUM> disclosed in the present embodiment, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> have almost the same configurations with that of the load cell <NUM> according to the above-described first embodiment such that the same effect is achieved with the load cell <NUM> according to the above-described first embodiment. More specifically, even if the weighted object having the weight M larger than the maximum weighting M1 of the tip-end load cell unit <NUM> or the maximum weighting M2 of the base-end load cell unit <NUM> is disposed on the weighting tray <NUM> of the load cell scale <NUM>, there is no elastic deformation exceeding the limit occurring in the tip-end load cell unit <NUM> and the base-end load cell unit <NUM>. Accordingly, it is possible to avoid unrecoverable deformation occurring in the load cell <NUM> having the tip-end load cell unit <NUM> and the base-end load cell unit <NUM>.

According to the load cell <NUM> disclosed in the present embodiment, since the accuracy and the maximum weighting of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> are different, it is possible to measure the weighted objects having different weight M by using different maximum weightings and measurement accuracies. Furthermore, according to the load cell <NUM> disclosed in the present embodiment, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> are integrated configured such that it is possible to improve the assembly precision and reduce the manufacturing cost and the maintenance cost of the load cell <NUM>.

Hereinafter, a first modification of the present embodiment will be described with reference to <FIG>. <FIG> is a front view showing a configuration of a load cell scale <NUM> having the load cell <NUM> according to the present modification example. <FIG> is a front view showing the configuration of the load cell <NUM> according to the present modification example. <FIG> are figures showing the operations of the load cell <NUM> according to the present modification example.

As shown in <FIG>, the load cell scale <NUM> according to the present modification example has the load cell <NUM>, the upper support member <NUM>, the lower support member <NUM>, the weighting tray <NUM>, and the base plate <NUM>. In the present modification example, the upper support member <NUM> is connected to the weighting tray <NUM> and the tip end of the load cell <NUM>, and the lower support member <NUM> is connected to the base end of the load cell <NUM> and the base plate <NUM>. In other words, in the present modification example, the tip end of the load cell <NUM> is connected to the upper support member <NUM> to receive the force from the weighting tray <NUM>. The base end of the load cell <NUM> and the lower support member <NUM> are connected with each other and then fixed to the base plate <NUM>. <FIG> shows that the weighted object having the weight M is disposed on the weighting tray <NUM> of the load cell scale <NUM>.

As shown in <FIG>, similar to the load cell <NUM> according to the above-described second embodiment, the load cell <NUM> according to the present modification example has the configuration that the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> are integrated in the direction of the longitudinal axis. As shown in <FIG>, each of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> has a first region <NUM> and a second region <NUM>. In the tip-end load cell unit <NUM> and the base-end load cell unit <NUM>, two second regions <NUM> are positioned at two sides of the first region <NUM>. As shown in <FIG>, the regions <NUM> of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> are designated as deformation regions and the regions <NUM> are shown by being surrounded by broken lines. In other words, in each of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM>, the first region <NUM> is formed between the second region <NUM> at the tip end side and the second region <NUM> at the base end side.

As shown in <FIG> and <FIG>, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> of the load cell <NUM> according to the present modification example have the same configurations with that of the load cell 10A according to the above-described first modification example of the first embodiment. In other words, the load cell <NUM> according to the present modification example has the configuration of using two load cells 10Aaccording to the above-described first modification example of the first embodiment to achieve the integrated configuration in the direction of the longitudinal axis.

Similar to the load cell 10A according to the above-described first modification example of the first embodiment, each of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> of the load cell <NUM> according to the present modification example has the stopper member <NUM> (second position-restriction member) formed in the T shape and the protrusion <NUM> (first position-restriction member) formed at the tip end side of the columnar body <NUM> of the load cell <NUM>. More specifically, for example, as shown in <FIG>, in the tip-end load cell unit <NUM>, the protrusion <NUM> and the tip-end free portion <NUM> of the stopper member <NUM> are disposed in the second region <NUM> at the tip end side, and the base-end fixing portion <NUM> of the stopper member <NUM> is fixed in the second region <NUM> at the base end side. Accordingly, the stopper member <NUM> is formed to be across the first region <NUM> of the tip-end lad cell unit <NUM>. In the present modification example, a combination of the protrusion (first position-restriction member) <NUM> formed in the columnar body <NUM> and the stopper member (second position-restriction member) <NUM> is defined as a position-restriction mechanism <NUM>.

Similar to the tip-end load cell unit <NUM>, the base-end load cell unit <NUM> has the position-restriction mechanism <NUM> configured from the protrusion (first position-restriction member) <NUM> formed in the columnar body <NUM> and the stopper member (second position-restriction member) <NUM>. In the present modification example, the position-restriction mechanism is configured to protect the first region <NUM> as the deformation region in the base-end load cell unit <NUM> and the tip-end load cell unit <NUM>.

More specifically, for example, in the tip-end load cell unit <NUM> of the load cell <NUM> according to the present modification example, a penetration hole <NUM> having an internal diameter larger than the diameter of the protrusion <NUM> is formed in the tip-end free portion <NUM> of the stopper member <NUM>. In the case in which the weighted object is not disposed on the weighting tray <NUM> of the load cell scale <NUM>, the elastic deformation does not occur in the tip-end load cell unit <NUM>, and the protrusion <NUM> is freely movable in the penetration hole <NUM> and accommodated therein. The load cell <NUM> according to the present modification example has the configuration such that an alignment of the protrusion (first position-restriction member) <NUM> formed in the columnar body <NUM> and the stopper member (second position-restriction member) <NUM> may be performed with a better accuracy.

On the other hand, the base-end load cell unit <NUM> of the load cell <NUM> according to the present modification example has the same configuration with the above-described tip-end load cell unit <NUM> and the description will be omitted.

As shown in <FIG>, in the present modification example, the stopper member <NUM> is formed in the substantially T shape, and the stopper member <NUM> is a plate-shaped member formed from the metal material having a suitable rigidity such as the iron and the like. However, the configuration of the stopper member <NUM> is not limited thereto. For example, the stopper member <NUM> may be suitably formed in a shape besides the T shape.

As shown in <FIG>, the stopper member <NUM> according to the present modification example is formed to have the step portion <NUM>, however, the configuration of the stopper member <NUM> is not limited thereto. Similar to the above-described embodiments and corresponding modification examples, the load cell <NUM> may be configured to have the intermediate portion <NUM> that is sandwiched by the stopper member <NUM> and the columnar body <NUM>.

In the load cell <NUM> according to the present modification example, the maximum weighting M1 increase to the maximum weighting M2 in the sequence from the tip-end load cell unit <NUM> to the base-end load cell unit <NUM>. In the load cell <NUM> according to the present modification example, the resolution (measurement accuracy) of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> may be different.

Next, operations of the load cell <NUM> according to the present modification example will be described with reference to <FIG>. More specifically, the operations of the load cell <NUM> according to the present modification example will be described according to the relationship of the weight M of the weighted object, the maximum weighting M1 of the tip-end load cell unit <NUM> of the load cell <NUM>, and the maximum weighting M2 of the base-end load cell unit <NUM> of the load cell <NUM>.

As shown in <FIG>, in the state in which there is no weighted object disposed on the weighting tray <NUM> of the load cell scale <NUM>, in the tip-end load cell unit <NUM> and the base-end load cell unit <NUM>, each protrusion (first position-restriction member) <NUM> is positioned in the corresponding penetration hole <NUM> and the protrusion <NUM> does not contact with the internal surface of the corresponding penetration hole <NUM>. In other words, in this state, the protrusion <NUM> is freely movable in the corresponding penetration hole <NUM>.

Next, a case in which the weight M of the weighted object is less than the maximum weighting M1 of the tip-end load cell unit <NUM> of the load cell <NUM> will be described. As shown in <FIG>, when the weighted object is disposed on the weighting tray <NUM> of the load cell scale <NUM> having the load cell <NUM>, the weight M of the weighted object applies on the load cell <NUM> as the load. Since the weight M of the weighted object is less than the maximum weighting M1 of the tip-end load cell unit <NUM>, the elastic deformation occurs in the penetration hole <NUM> (first region <NUM>) as the strain portion of the tip-end load cell unit <NUM>, however there is almost no elastic deformation occurring in the first region of the base-end load cell unit <NUM>. In this state, the elastic deformation occurs in the first region <NUM> of the tip-end load cell unit <NUM> such that the protrusion <NUM> moves in the penetration hole <NUM>, however, the protrusion <NUM> does not contact with the internal surface of the penetration hole <NUM>.

When the weighted object having the weight equal to the maximum weighting M1 of the tip-end load cell unit <NUM> is disposed on the weighting tray of the load cell scale <NUM>, the first region <NUM> of the tip-end load cell unit <NUM> is deformed to reach the limit of the elastic deformation such that the protrusion <NUM> contacts with the internal surface of the penetration hole <NUM>. In other words, in this state, the protrusion (first position-restriction member) <NUM> of the tip-end load cell unit <NUM> contacts and engages with the internal surface of the penetration hole <NUM> such that the stopper member (second position-restriction member) <NUM> and the columnar body <NUM> in the tip-end load cell unit <NUM> become the integrated configuration. In this state, the first region <NUM> of the tip-end load cell unit <NUM> almost reaches the limit of the elastic deformation; however, there is almost no elastic deformation occurring in the first region <NUM> of the base-end load cell unit <NUM>.

Next, a case in which the weighted object having the weight M larger than the maximum weighting M1 of the tip-end load cell unit <NUM> and less than the maximum weighting M2 of the base-end load cell unit <NUM> is disposed on the weighting tray of the load cell <NUM> will be described. In this case, as shown in <FIG>, the stopper member <NUM> of the tip-end load cell unit <NUM> and the columnar body <NUM> have become the integrated configuration, therefore the state in which the first region <NUM> of the tip-end load cell unit <NUM> is deformed to reach the limit of the elastic deformation is retained and no further deformation occurring in the first region <NUM>. At this time, in the tip-end load cell unit <NUM>, it is possible to prevent the further deformation exceeding the limit of the elastic deformation occurring in the first region <NUM> so as to avoid the malfunctions in the tip-end load cell unit <NUM>.

On the other hand, the weight M of the weighted obj ect applies to the base-end load cell unit <NUM> as the load and the elastic deformation occurs in the first region <NUM> as the strain portion in the base-end load cell unit <NUM>. In this case, the tip-end cell unit <NUM> may be recognized as part of the base-end cell unit <NUM>. At this time, due to the elastic deformation occurring in the first region <NUM> as the strain portion in the base-end load cell unit <NUM>, in the base-end load cell unit <NUM>, the protrusion <NUM> moves in the penetration hole <NUM> in response to the elastic deformation amount of the first region <NUM>. However, in this case, the protrusion <NUM> does not contact with the internal circumferential surface of the penetration hole <NUM>.

According to the load cell scale <NUM> disclosed in the present modification example, it is possible to measure the weight M of the weighted object by detecting the electrical signals indicating the elastic deformation amount of the first region <NUM> of the base-end load cell unit <NUM>.

In a case in which the weighted object having the weight M larger than the maximum weighting M2 of the base-end load cell unit <NUM>, both of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> enter the state in which the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> are deformed to reach the limit of elastic deformation. As shown in <FIG>, in this state, in each of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM>, the protrusion <NUM> contacts and engages with the internal circumferential surface of the corresponding penetration hole <NUM>. In other words, at this time, the stopper member <NUM> and the columnar body <NUM> in the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> become the integrated configuration. Accordingly, in the load cell <NUM> according to the present modification example, it is possible to prevent the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> from deforming exceeding the limit of the elastic deformation.

According to the load cell <NUM> and the load cell scale <NUM> having the load cell <NUM> disclosed in the present modification example, the configuration of the position-restrict ion mechanism <NUM> configured from the protrusion (first position-restriction member) <NUM> and the stopper member (second position-restriction member) <NUM> is different from that according to the above-described second embodiment, however, the same effect with the above-described second embodiment may be achieved.

Hereinafter, the load cell <NUM> according to the second modification example of the present embodiment will be described with reference to <FIG> and <FIG>. As shown in <FIG>, the load cell according to the present modification example has the configuration that the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> is integrated in the direction of the longitudinal axis. Also, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> have the same configuration as that of the load cell 10B according to the above-described second modification example of the first embodiment.

More specifically, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> according to the present modification example are configured to have position-restriction tank (first position-restriction member) <NUM> (see <FIG>) connected and fixed to the columnar body <NUM> and the stopper member (second position-restriction member) <NUM> formed in the substantial T shape. As shown in <FIG>, in the tip-end load cell unit <NUM> and the base-end load cell unit <NUM>, the base-end fixing portion <NUM> of the stopper member <NUM> and the position-restriction tank <NUM> are connected and fixed to the columnar body <NUM> of the load cell <NUM> by the fixing mechanism <NUM>. At least part of the tip-end free portion <NUM> of the stopper member <NUM> is covered by the corresponding position-restriction tank <NUM> in the direction of the longitudinal axis. In other words, at least part of the tip-end free portion <NUM> of the stopper member <NUM> is accommodated in the position-restriction tank <NUM>.

As shown in <FIG>, in the height direction of the load cell <NUM> according to the present modification example, the tip-end free portion <NUM> of the stopper member <NUM> and the position-restriction tank <NUM> are separated by a predetermined interval. The interval between the tip-end free portion of the stopper member <NUM> and the position-restriction tank <NUM> is suitably determined according to the maximum elastic deformation amount of the strain portion corresponding to the maximum weighting M1 of the tip-end load cell unit <NUM> and the maximum weighting M2 of the base-end load cell unit <NUM>. In the present modification example, the maximum weighting M1 of the tip-end load cell unit <NUM> may be less than the maximum weighting M2 of the base-end load cell unit <NUM>.

As shown in <FIG>, in the base-end fixing portion <NUM> of the tip-end load cell unit <NUM> of the load cell <NUM> according to the present modification example, the step portion <NUM> having the width H3 in the height direction may be provided. The load cell <NUM> according to the present modification example has the step portion <NUM> so as to prevent the base-end fixing portion <NUM> of the stopper member <NUM> from unintentionally contacting with the internal surface of the groove portion <NUM>. Accordingly, when the weighted object is disposed on the load cell <NUM>, the deformation amount of the columnar body <NUM> can be correctly recognized. The step portion <NUM> is formed in only part of the base-end fixing portion <NUM> of the stopper member <NUM> such that it is possible to retain the rigidity of the tip-end load cell unit <NUM>.

As shown in <FIG>, the example that the base-end fixing portion <NUM> of the base-end load cell unit <NUM> is separated from the internal surface of the groove portion <NUM> for an interval is described, however, the present modification example is not limited thereto. For example, similar to the tip-end load cell unit <NUM>, the base-end load cell unit <NUM> may have the base-end fixing unit <NUM> where the step portion <NUM> formed therein.

In the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> of the load cell <NUM> according to the present modification example, a combination of the position-restriction tank (first position-restriction member) <NUM> and the stopper member (second position-restriction member) <NUM> is defined as the position-restriction mechanism <NUM>. Accordingly, according to the load cell <NUM> disclosed in the present modification example, similar to the above-described embodiments and modification examples, the movement range of the stopper member <NUM> is restricted by the position-restriction tank <NUM> such that it is possible to prevent the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> from deforming to exceed the limit of the elastic deformation so as to avoid the malfunctions.

More specifically, for example, in the load cell scale <NUM> having the load cell <NUM> according to the present modification example, in the case of weighting the weighted object having the weight M that is larger than the maximum weighting M1 of the tip-end load cell unit <NUM> and less than the maximum weighting M2 of the base-end load cell unit <NUM>, the stopper member <NUM> engages with the internal surface of the position-restriction tank <NUM> of the tip-end load cell unit <NUM> to be in the integrated state, and the weight M of the weighted object applies on the base-end load cell unit <NUM> as the load. At this time, the tip-end free portion <NUM> of the stopper member <NUM> of the base-end load cell unit <NUM> moves in the corresponding position-restriction tank <NUM>, however, the tip-end free portion <NUM> does not contact with the internal surface of the position-restriction tank <NUM>. In this state, the weight M of the weighted object is measured by detecting the signals indicating the elastic deformation amount in the strain portion of the base-end load cell unit <NUM>.

According to the load cell <NUM> and the load cell scale <NUM> having the load cell <NUM> according to the present modification example, the same effect with that of the load cells and the load cell scales according to the above-described various embodiments and modification examples is achieved.

<FIG> shows a configuration of the load cell <NUM> according to the third modification example of the present embodiment. As shown in <FIG>, the load cell <NUM> according to the present modification example is configured to have the tip-end load cell unit <NUM>, an intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> fixed to the columnar body <NUM> sequentially in the sequence from the tip end side toward the base end side in the direction of the longitudinal axis. As shown in <FIG>, each of the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> has the stopper member <NUM> fixed to the groove portion <NUM> formed in the lateral surface <NUM> of the columnar body <NUM>.

In the load cell <NUM> according to the present modification example, the maximum weighting M1 of the tip-end load cell unit <NUM>, the maximum weighting M2 of the intermediate load cell unit <NUM>, and the maximum weighting M3 of the base-end load cell unit <NUM> may be set to increase in this sequence. The tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> may have different resolutions (measurement accuracies).

Similar to the load cell <NUM> (see <FIG>) according to the above-described second embodiment, the load cell <NUM> according to the present modification example has the configuration such that when the weighted object having the weight M larger than the maximum weighting of each load cell unit or the unintentional impact applies on the load cell scale <NUM>, it is possible to prevent the deformation exceeding the limit of the elastic deformation and malfunctions occurring in each load cell unit <NUM>, <NUM>, <NUM>.

The load cell <NUM> according to the present modification example, compared with the load cell <NUM> according to the above-described second embodiment, it is possible to further expand the maximum weighting of the load cell scale <NUM> with a simple configuration. Accordingly, it is possible to configure a complex load cell scale having the maximum weighting and resolution as desired by combining various load cell units disclosed in the above-described embodiments and modification examples of the present invention.

An example of the load cell <NUM> according to the present modification that the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> have the same configuration is described, however, the present modification example is not limited thereto. For example, the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> may be configured by combining the various configurations according to the above-described first embodiment and the corresponding modification examples.

Hereinafter, the load cell <NUM> and the load cell scale <NUM> having the load cell <NUM> according to a third embodiment of the present invention will be described with reference to <FIG>. <FIG> and <FIG> are front views showing the configuration of part of the load cell <NUM> according to the present embodiment, more specifically, showing the configuration of the tip-end load cell unit <NUM> of the load cell <NUM>. <FIG> is a front view showing the configuration of load cell according to the present embodiment. <FIG> and <FIG> are front view and perspective view showing the load cell scale <NUM> having the load cell <NUM> respectively. <FIG> and <FIG> are front views showing the operations of the load cell <NUM> according to the present embodiment.

As shown in <FIG>, the load cell <NUM> according to the present embodiment is configured to have three load cell units connected with each other. More specifically, the load cell <NUM> according to the present embodiment is configured to have the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> indirectly connected via the intermediate load cell unit <NUM>.

As shown in <FIG> and <FIG>, each of the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> according to the present embodiment is configured by connecting the stopper member (second position-restriction member) <NUM> to the lateral surface of the columnar body <NUM>. For example, in the tip-end load cell unit <NUM> shown in <FIG>, the first region <NUM> having the penetration hole <NUM> formed as the strain portion and two second regions <NUM> formed at the two sides of the first region <NUM> are formed in an intermediate portion in the direction of the longitudinal axis of the columnar body <NUM>. Similar to the above-described embodiments and corresponding modification examples, the first region <NUM> according to the present embodiment is formed as the deformation region of the tip-end load cell unit <NUM>. As shown in <FIG>, the tip-end load cell unit <NUM> has the base-end fixing portion <NUM> of the stopper member <NUM> that is connected and fixed to the columnar body <NUM> by the fixing mechanism <NUM>. On the other hand, the penetration hole <NUM> is formed in the tip-end free portion <NUM> of the tip-end load cell unit <NUM>, and the protrusion (first position-restriction member) <NUM> formed to protrude from the lateral surface at the tip end side of the columnar body <NUM> is positioned in the penetration hole <NUM>. According to the present embodiment, the external diameter of the protrusion <NUM> is smaller than the internal diameter of the penetration hole <NUM> such that the protrusion <NUM> is freely movable in the penetration hole <NUM>. According to the present embodiment, the combination of the protrusion (first position-restriction member) <NUM> formed in the columnar body <NUM> and the stopper member (second position-restriction member) <NUM> operates as the position-restriction mechanism <NUM> of the tip-end load cell unit <NUM>. The intermediate load cell unit <NUM> and the base-end load cell unit <NUM> may have almost the same configuration with that of the tip-end load cell unit <NUM>.

According to the present embodiment, in order to make the description easy, an example that in <FIG> and <FIG>, the right side in the figures is the base end side of the tip-end load cell unit <NUM>, and the left side in the figures is the tip end side of the tip-end load cell unit <NUM> is described, however, the present embodiment is not limited thereto. For example, as shown in <FIG>, according to the present embodiment, it is only necessary that the base end side of the tip-end load cell unit <NUM> and the tip end side of the intermediate load cell unit <NUM> are connected with each other by a connection member <NUM> having a predetermined rigidity, and the base end side of the intermediate load cell unit <NUM> and the tip end side of the base end load cell unit <NUM> are connected with each other by the connection member <NUM>, the extending direction from the base end side toward the tip end side of each load cell unit is not particularly limited. In other words, according to the present embodiment, the three load cell units <NUM>, <NUM>, <NUM> only have to be connected with each other to form a hairpin curve shape. For example, when the weighted object having the weight M is disposed on the weighting tray <NUM> of the load cell scale <NUM> as described below, it is preferable that the connection member <NUM> according to the present embodiment has the rigidity suitable for supporting the weighted object, the tip-end load cell unit <NUM>, and the intermediate load cell unit <NUM>, however, the shape and the material of the connection member <NUM> are not particularly limited.

The load cells according to the above-described embodiments and modification examples are configured by the integrated configuration of various load cell units in the direction of the longitudinal axis, that is, in the horizontal direction. However, as shown in <FIG>, the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> according to the present embodiment are stacked in the height direction (Z-axis direction, vertical direction) of the load cell <NUM>. The load cell <NUM> according to the present embodiment has such a module construction such that it is easy to expand the maximum weighting of the load cell <NUM> by adding the load cell unit. According to the present embodiment, the load cell <NUM> configured from three load cell units of the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> is described, however, the present embodiment is not limited thereto. For example, as shown in <FIG> and <FIG>, the load cell <NUM> may be configured by the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> only, or the load cell <NUM> may be configured by equal to or more than four load cell units that is not shown in figures.

In <FIG> and <FIG>, the configuration of the load cell scale <NUM> having the load cell <NUM> that is configured by using the connection member <NUM> to connect the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> is shown. As shown in <FIG>, the weighting tray <NUM> is connected to the tip end side of the tip-end load cell unit <NUM> via the upper support member <NUM>. Also, the base plate <NUM> is connected to the base end side of the base-end load cell unit <NUM> via the lower support member <NUM>. Accordingly, when the weighted member having the weight M is disposed on the weighting tray <NUM> of the load cell scale <NUM>, the weight M of the weighted object can be measured by detecting the deformation amount of each load cell unit in the load cell <NUM>.

Hereinafter, operations of the load cell scale <NUM> having the load cell <NUM> according to the present embodiment will be described with reference to <FIG> and <FIG>. Since the load cell scale <NUM> according to the present embodiment has the load cell <NUM> configured from three load cell units <NUM>, <NUM>, <NUM>, the maximum weighting suitable for weighting is in three steps. Hereinafter, an example of the load cell <NUM> according to the present embodiment that the maximum weighting M1 (for example, three kilograms) of the tip-end load cell unit <NUM>, the maximum weighting M2 (for example, six kilograms) of the intermediate load cell unit <NUM>, and the maximum weighting M3 (for example, fifteen kilograms) of the base-end load cell unit are increased in this sequence will be described. For example, the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> may have different resolutions (measurement accuracies).

As shown in <FIG>, in the case when the weighted object having the weight M is disposed on the weighting tray <NUM> of the load cell scale <NUM> according to the present embodiment, operations of the load cell scale <NUM> will be described according to the relationship of the weight M of the weighted object and each of the maximum weightings of the three load cell units of the load cell <NUM>.

Firstly, the case in which the weight M of the weighted object is less than the maximum weighting M1 of the tip-end load cell unit <NUM> of the load cell <NUM> will be described. In this case, the weight M of the weighted object applies to the tip-end load cell unit <NUM> as the load, and the elastic deformation occurs in the first region <NUM> as the deformation portion in the tip-end load cell unit <NUM> such that the protrusion <NUM> provided in the columnar body <NUM> moves in the penetration hole <NUM> formed in the tip-end free portion <NUM> of the stopper member <NUM>; however, the protrusion <NUM> does not contact with the internal circumferential surface of the penetration hole <NUM>. In this state, the weight M of the weighted object can be measured by detecting the electrical signals indicating the elastic deformation amount of the first region of the tip-end load cell unit <NUM>.

Next, in the case when the weight M of the weighted object is larger than the maximum weighting M1 of the tip-end load cell unit <NUM> and less than the maximum weighting M2 of the intermediate load cell unit <NUM>, as shown in <FIG>, similar to the load cells according to the above-described embodiments and the corresponding modification examples, the protrusion <NUM> formed in the columnar body <NUM> of the tip-end load cell unit <NUM> contacts with the internal circumferential surface of the penetration hole <NUM> formed in the tip-end free portion <NUM> of the stopper member <NUM>. In other words, in this state, the protrusion <NUM> cannot move in the penetration hole <NUM> formed in the stopper member <NUM> such that the elastic deformation of the first region <NUM> of the tip-end load cell unit <NUM> is restricted by the stopper member <NUM>. Accordingly, the columnar body <NUM> and the stopper member <NUM> in the tip-end load cell unit <NUM> become the integrated configuration so as to be recognized as part of the configuration at the tip end side of the intermediate load cell unit <NUM>.

In this state, the weight M of the weighted member applies to the intermediate load cell unit <NUM> as the load, and the protrusion <NUM> in the intermediate load cell unit <NUM> moves in the penetration hole <NUM> formed in the corresponding stopper member <NUM>. Similar to the operations of the above-described tip-end load cell unit <NUM>, the weight M of the weighted object can be measured by detecting the signals indicating the elastic deformation amount of the first region <NUM> in the intermediate load cell unit <NUM>. In this state, the first region <NUM> of the tip-end load cell unit <NUM> has reached the limit of the elastic deformation; however, the elastic deformation may occur in the first regions <NUM> of the intermediate load cell unit <NUM> and the base-end load cell unit <NUM>.

Furthermore, in the case when the weight M of the weighted object is larger than the maximum weighting M2 of the intermediate load cell unit <NUM> and less than the maximum weighting M3 of the base-end load cell unit <NUM>, as shown in <FIG>, in the tip-end load cell unit <NUM> and the intermediate cell unit <NUM>, the protrusion <NUM> formed in the columnar body <NUM> contacts the internal circumferential surface of the penetration hole <NUM> formed in the corresponding stopper member <NUM>. In other words, the columnar body <NUM> and the stopper member <NUM> become the integrated configuration in each of the tip-end load cell unit <NUM> and the intermediate load cell unit <NUM>. In this state, the weight M of the weighted object applies to the base-end load cell unit <NUM> as the load such that in the base-end load cell unit <NUM>, the elastic deformation occurs in the first region and the protrusion <NUM> formed in the columnar body <NUM> moves in the penetration hole <NUM> of the corresponding stopper member <NUM>. Similar to the above-described cases, the weight M of the weighted object can be measured by detecting the signals indicating the elastic deformation amount in the first region <NUM> of the base-end load cell unit <NUM>.

Even if it is not disclosed in figures, in the case in which the weight M of the weighted object is larger than the maximum weighting of the base-end load cell unit <NUM>, in each of the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> having the load cell <NUM>, the protrusion <NUM> formed in the columnar body <NUM> contacts with the internal circumferential surface of the penetration hole <NUM> formed in the stopper member <NUM>. Accordingly, in these load cell units <NUM>, <NUM>, <NUM> of the load cell <NUM>, further elastic deformation in each region <NUM> is restricted by the corresponding stopper member <NUM>.

According to the load cell <NUM> disclosed in the present embodiment, similar to the above-described embodiments and modification examples, it is possible to avoid the deformation exceeding the limit of the elastic deformation in the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> and prevent the malfunctions of the load cell <NUM>.

Hereinafter, a first modification example, a second modification example, and a third modification example of the load cell <NUM> according to the present embodiment will be described with reference to <FIG>.

As shown in <FIG>, similar to the load cell <NUM> according to the present embodiment, the load cell <NUM> according to the first modification example of the present embodiment is configured by using the connection member <NUM> to connect the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> in the state of being stacked in the vertical direction. In the load cell <NUM> according to the present modification example, the tip-end load cell unit <NUM>, the intermediate load cell unit <NUM>, and the base-end load cell unit <NUM> have the same configuration as that of the load cell <NUM> (see <FIG>) according to the first embodiment.

<FIG> shows the configuration of the load cell <NUM> according to the second modification example of the present embodiment. As shown in <FIG>, the load cell <NUM> according to the present modification example is configured by using the connection member <NUM> to connect the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> in the state of being stacked in the vertical direction. Similar to the above-described first modification example of the present embodiment, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> have the same configuration as that of the load cell <NUM> (see <FIG>) according to the first embodiment. It is possible to configure a further compact load cell scale <NUM> using the load cell <NUM> according to the present modification example and correspond to the weighting for a relative light weighted object.

<FIG> shows the configuration of the load cell according to the third modification example of the present embodiment. The load cell <NUM> according to the present modification example is different from the second modification example of the present embodiment in the configurations of the tip-end load cell unit <NUM> and the base-end load cell unit <NUM>. More specifically, the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> have the same configuration as that of each load cell unit of the load cell <NUM> (see <FIG> and <FIG>) according to the third embodiment.

As described above, several modification examples of the load cell <NUM> according to the present embodiment are described, however, the present embodiment is not limited thereto. The several modification examples of the present embodiment are used to describe the feature that it is easy to expand the weighting of the load cell using the modulated load cell units in the load cell <NUM>. For example, in the several modification examples, it is described that the several load cell units included in the load cell have the same configuration, however, the present embodiment is not limited thereto. In other words, in the load cell <NUM> according to the present embodiment and each modification example, the load cell having different configuration according to the first embodiment and the corresponding modification examples may be suitably combined.

According to the load cell <NUM> disclosed in the present embodiment and each modification example, it is easy to expand the weighting and it is possible to avoid the deformation exceeding the limit of the elastic deformation in each load cell unit configuring the load cell <NUM> by using a simple configuration so as to prevent the malfunctions of the load cell <NUM>.

Hereinafter, a fourth embodiment of the present invention will be described with reference to <FIG> and <FIG>. <FIG> is a perspective view showing a configuration of the load cell according to the present embodiment. <FIG> is a cross-sectional view along the break line A-A in <FIG>.

As shown in <FIG>, the load cell <NUM> according to the present embodiment is configured to have a protection member <NUM> attached to the load cell <NUM> according to the second embodiment. As shown in <FIG>, in the load cell <NUM> according to the present embodiment, the protection member <NUM> connected to the tip-end load cell unit <NUM>, for example, is fixed to the tip end surface of the tip-end load cell unit <NUM> in a state of covering at least part of the tip-end load cell unit <NUM>.

More specifically, as shown in <FIG>, in the upper surface <NUM> of the columnar body <NUM> of the load cell <NUM>, a plate-shaped member <NUM> is connected and fixed thereto by screws <NUM>. On the other hand, the protection member <NUM> has two second stopper members <NUM> at positions facing the plate-shaped member <NUM> along the height direction of the load cell <NUM>. According to the present embodiment, as shown in <FIG>, for example, the second stopper member <NUM> may be configured by using the screw attached to the top plate of the protection member <NUM>, however, the second stopper member <NUM> is not limited thereto. For example, the second stopper member <NUM> may be a pin protruding from the top plate of the protection member <NUM> toward the plate-shaped member <NUM>. As shown in <FIG>, when an external force is not applied to the load cell <NUM>, the second stopper member <NUM> and the plate-shaped member <NUM> are separated from each other by a distance h. As described below, the second stopper member <NUM> has a width in the short direction of the plate-shaped member <NUM> such that in the case when the top plate of the protection member <NUM> receives the external force to be bent, the second stopper member <NUM> moves downward to contact with the plate-shaped member <NUM>. According to the present embodiment, the protection member <NUM> and the plate-shaped member <NUM> may be formed from the metal materials having the predetermined rigidity.

In the load cell <NUM> according to the present embodiment, the combination of the protection member <NUM> and the plate-shaped member <NUM> fixed to the load cell <NUM> is configured to protect each configuration of the load cell <NUM> from any unintentional external impact. More specifically, in the case when the external force that is much larger than the maximum weighting of the load cell <NUM> applies on the load cell <NUM>, for example, when a baggage having a weight of <NUM> kilograms that is <NUM> times of the maximum weighting as <NUM> kilograms of the load cell <NUM> falls and collides with the load cell <NUM>, it is possible that the real-time impact to the load cell <NUM> is much larger than the considerable impact to the stopper member <NUM> provided in the load cell <NUM>. In this state, since the impact cannot be absorbed only by the stopper member <NUM>, it is possible that the deformation exceeding the limit of elastic deformation occurs in the load cell <NUM> so as to generate the permanent strain therein.

According to the load cell <NUM> disclosed in the present embodiment, at the time when the external unintentional impact applies, the force due to the impact firstly applies to the protection member <NUM>. When the protection member <NUM> receives the force, the top plate bends downwardly in the height direction of the load cell <NUM> to deform. Accordingly, as shown in <FIG>, the second stopper members <NUM> provided in the protection member <NUM> moves downwardly toward the plate-shaped member <NUM>. In other words, the distance h between the second stopper members <NUM> and the plate-shaped member <NUM> decreases. When the force due to the external impact is large, the second stopper members <NUM> moves downwardly until the second stopper members <NUM> contact with the plate-shaped member <NUM>. Also, since the protection member <NUM> is connected with the tip-end load cell unit <NUM> of the load cell <NUM>, part of the force is transmitted to the tip-end load cell unit <NUM> such that stopper member <NUM> included in the tip-end load cell unit <NUM> moves simultaneously. Furthermore, in some cases, the stopper member <NUM> included in the base-end load cell unit <NUM> also moves simultaneously.

That is, when the unintentional impact applies to the load cell <NUM> according to the present embodiment, the second stopper member <NUM> included in the protection member <NUM>, the stopper members <NUM> provided in the tip-end load cell unit <NUM> and the base-end load cell unit <NUM> of the load cell <NUM> moves simultaneously such that the protection member <NUM>, the columnar body <NUM> of the load cell <NUM> and the various stopper member <NUM> contact with each other to become the integrated configuration. According to the present embodiment, the protection member <NUM> has a large force receiving area for receiving the force from the height direction of the load cell <NUM> and the protection member <NUM> is formed from the material having the predetermined rigidity. Accordingly, it is considerable that the rigidity of the configuration formed by combining the columnar body <NUM> and the stopper member <NUM> of the load cell <NUM> together with the protection member <NUM> can be significantly improved.

According to the load cell <NUM> disclosed in the present embodiment, in the case in which the stopper member <NUM> is not provided in the tip-end load cell unit <NUM>, it is also possible to avoid the unintentional deformation in the tip-end load cell unit <NUM> and the base-end load cell unit only by the operations of the protection member <NUM>.

According to the above description, due to the load cell <NUM> according to the present embodiment, even if the unintentional impact applies to the load cell <NUM>, it is possible to avoid the deformation exceeding the limit of the elastic deformation in each load cell unit of the load cell <NUM> by the protection member <NUM> so as to prevent the malfunctions in the load cell <NUM>. According to the present embodiment, in the case when the second stopper member <NUM> is configured by the screw, it is considerable to adjust the magnitude of the impact that can be absorbed by the protection member <NUM> by only adjusting the distance between the second stopper member <NUM> and the plate-shaped member <NUM>.

The configuration of the protection member <NUM> in the load cell <NUM> according to the present embodiment is described based on the configuration example shown in <FIG> and <FIG>, however, the configuration of the protection member <NUM> is not limited thereto. In the present embodiment, for example, the second stopper member <NUM> may be provided in the upper support member <NUM> (see <FIG>) according to the second embodiment.

In the present description, the phrases showing positional relationship such as "upper", "lower", "tip end", "base end", "left side", "right side", "vertical", "horizontal", "top", "bottom", "internal", and "external" are used. However, such phrases are only used to make the description easy and indicate the positional relationship shown in the enclosed figures. In other words, the configurations according to each embodiment and modification example of the present invention are not limited by these phrases.

The embodiments of the invention have been described above with reference to the drawings, but specific structures of the invention are not limited to the embodiments and may include various modifications without departing from the scope of the invention. The invention is not limited to the above-mentioned embodiments and is limited only by the accompanying claims.

Claim 1:
A load cell scale (<NUM>), comprising:
a load cell part (<NUM>) formed in a columnar shape, the load cell part (<NUM>) having an upper surface (<NUM>) extending along a longitudinal axis (L) and a lateral surface (<NUM>) intersecting with the upper surface (<NUM>), and the load cell part (<NUM>) having a first load cell (<NUM>) with a first weighting and a second load cell (<NUM>) with a second weighting,
wherein the load cell part (<NUM>) has the first load cell (<NUM>) and the second load cell (<NUM>) to be disposed along a longitudinal direction or a height direction, and
wherein the load cell part (<NUM>) has a strain portion (<NUM>) capable of elastically deforming and the strain portion (<NUM>) penetrates the first load cell (<NUM>) and the second load cell (<NUM>) from the lateral surface (<NUM>) in a short direction orthogonal to the longitudinal direction,
characterized in that the load cell part further comprises:
a stopper part (<NUM>) configured to restrict deformation occurring in the load cell part (<NUM>) due to a load exceeding a predetermined value and applied to the load cell part (<NUM>), the stopper part (<NUM>) being configured to correspond to either of the first load cell (<NUM>) or the second load cell (<NUM>),
wherein the stopper part (<NUM>) is a plate-shaped member formed to extend along the longitudinal direction,
the stopper part (<NUM>) comprising:
a fixing-end portion fixed to the lateral surface (<NUM>) of the load cell part (<NUM>); and
a free-end portion separating from the fixing-end portion along the longitudinal axis (L), the free-end portion being configured to restrict the elastic deformation of the load cell part (<NUM>) due to the load in a state when the fixing-end portion is fixed to the lateral surface (<NUM>),
wherein the stopper part (<NUM>) has a first stopper (<NUM>) and a second stopper (<NUM>) corresponding to the first load cell (<NUM>) and the second load cell (<NUM>) respectively, and
wherein the fixing-end portion of the first stopper (<NUM>) and the free-end portion of the second stopper (<NUM>) are adjacent to each other on the lateral surface (<NUM>).