TWI841083B - Load detector - Google Patents

Abstract

The load detector of the present invention comprises: a main body 5c and a supporting member 5b; the main body 5c comprises a detecting portion 5k and an extending portion 5m; the detecting portion 5k detects the load; the extending portion 5m extends from the detecting portion 5k in different directions from the direction of the load acting on the detecting portion 5k; the supporting member 5b comprises a portion contacting the extending portion 5m along the extending direction of the extending portion 5m, and a retaining portion 5a retaining an object to which the load W acts, and the distance between the detecting portion 5k and the retaining portion 5a is changed by moving the extending portion 5m along the extending direction.

Description

Load detector

This disclosure relates to load detectors.

In the process of rolling, printing, or processing foil materials such as paper, cloth, film, or metal foil, it is necessary to control the tension acting on the foil material to prevent undesirable conditions such as wrinkling, buckling, or printing deviation. The tension acting on the foil material detects the load that is wound around the foil material and acts on the roller. The detector for detecting the load is arranged on the outer periphery of the support bearing provided on at least one side of the roller via the bearing. The detector uses a load detector such as a force gauge. In addition, the load detector is mounted on the outer wall or the like using bolts. [Prior Technical Literature] [Patent Literature]

[Patent document 1] Japanese Patent No. 4-136238

[The problem that the invention wants to solve]

This type of load detector must use a rated capacity force gauge that matches the tension acting on the target object such as the roller axis of the support roller. Therefore, there is a problem that if the load acting on the target object changes due to changes in foil thickness, etc., it is necessary to reset the load detector with a different rated capacity.

Therefore, this disclosure is made in view of the above-mentioned problem, and its purpose is to obtain a load detector that can reduce the number of reset times of load detectors with different rated capacities even if the load on the object changes. [Means for solving the problem]

The disclosed load detector comprises: a main body and a supporting member; the main body comprises a detection part and an extension part; the detection part detects the load; the extension part extends from the detection part position in different directions of the load acting on the detection part; the supporting member comprises a portion contacting the extension part along the extension direction of the extension part, and a holding part holding an object of the load, and the distance between the detection part and the holding part is changed by moving the extension part along the extension direction. [Effect of the invention]

The load detector disclosed herein can reduce the number of reset times of load detectors with different rated capacities even if the load of the object changes.

The following is a description of the embodiments of the present disclosure using drawings. The same reference numerals in the drawings represent the same or corresponding parts.

Implementation form 1. Figure 1 shows a load detector installation configuration diagram of the implementation form 1 of the present disclosure. In addition, the Z-axis direction in Figure 1 is set as the parallel direction of the roller axis 3, the Y-axis direction is set as the height direction of the load detector 5 (the details are described later, the vector and direction of the tension applied by the foil 1 to the load detector 5), and the axis orthogonal to the Z-axis and the Y-axis is set as the X-axis (the paper depth direction of Figure 1). The same coordinate symbols are also used in the following figures. Implementation form 1 is as shown in Figure 1, and is supported by the roller 2a via the load detector 5 and the roller axis 3 in the form of being clamped by the opposite fixing members 7.

The fixed member 7 is fixed to one end of the load detector 5, and the other end of the load detector 5 is fixed to the roller axis 3, and the roller axis 3 becomes the axis of the roller 2a. The roller 2a rotates about the roller axis 3 to transfer the foil material 1 such as paper, cloth, film, or metal foil supported by the roller 2a. In addition, the fixed member 7 is, for example, a factory wall surrounding the equipment for conveying the foil material 1, or a support provided near the equipment for conveying the foil material 1, and is a member for fixing the load detector 5 in such a manner that the load can be detected without displacement even if the foil material 1 bears the load.

FIG2 is a cross-sectional view taken along the line arrow direction of the A-A line in FIG1. As shown in FIG2, the foil material 1 is transferred by roller 2b and roller 2c in addition to roller 2a. Roller 2a, roller 2b and roller 2c are arranged separately in the X-axis direction, and roller 2a is arranged at a higher position than roller 2b or roller 2c in the Y-axis direction. Roller 2a rotates in the direction of arrow 3a in FIG2, and rollers 2b and 2c rotate synchronously with roller 2a to apply tension T to the foil material 1. The direction of tension T is the long side direction of the foil material 1.

At this time, the tension T from roller 2a to roller 2c and the tension T from roller 2a to roller 2b are equal. The resultant force W of the two tensions T acts on the load detector 5. In addition, the direction of the resultant force W is the height direction (±Y direction) of the load detector 5. If the vector angle between the tension T and the resultant force W is set to θ, the resultant force W is expressed by formula 1:

[Number 1] W=2×T×cosθ

FIG3 is a cross-sectional view of the main part of the load detector 5 of the embodiment 1 of the present disclosure. The load detector 5 is symmetrical in the Y-axis direction relative to the axis 3b of the roller 2a. The axis 3b of the roller 2a is consistent with the central axis of the body 5c. The load detector 5 is composed of a body 5c and a support member 5b that can be separated from the body 5c.

The main body 5c is composed of a fixing portion 51 and an extension portion 5m. The fixing portion 51 has a screw hole for screwing the main body mounting screw 6 on the fixing member 7. The extension portion 5m extends in a direction different from the load W direction acting on the roller 2a and the roller axis 3 (more specifically, in a vertical direction). The extension portion 5m has a detection portion 5k that can detect the load generated in the load W direction. The extension portion 5m extends from the detection portion 5k in a direction different from the detection axis of the detection portion 5k (the axis for detecting the load in the direction parallel to the load W direction). The load W is the resultant force of the tension T generated by the roller shaft 3 and the roller 2a inserted in the bearing provided on the supporting member 5b described later, and the force from the foil is expressed as an equivalent concentrated load. For the purpose of explanation below, the resultant force W acting on the holding portion 5a described later is defined as the "generated load", and the load detected by the detection portion 5k is defined as the "detection load".

The supporting member 5b is hollow, and a cavity 4 is formed inside. The extension 5m of the main body 5c is inserted into the inner side from one end of the supporting member 5b, so that the supporting member 5b contacts the main body 5c. The supporting member 5b can move in the vertical direction of the load W, and the insertion depth between the supporting member 5b and the extension 5m can be changed by moving. If the supporting member 5b moves in the direction away from the fixing portion 51 of the main body 5c, the insertion depth between the supporting member 5b and the extension 5m becomes shallow.

The other end of the supporting member 5b has a bearing, and the roller axis 3 is fixed via the bearing. The bearing belongs to the retaining portion 5a. That is, the retaining portion 5a is located on the supporting member extending from the detection portion 5k toward the extension portion 5m. The supporting member 5b can move along the extension direction of the extension portion 5m, and by moving along the extension direction, the distance between the detection portion 5k and the retaining portion 5a can be changed. In addition, the extension portion 5m of the present embodiment is a cylindrical shape extending in the moving direction of the supporting member 5b, but it can also be a cylindrical shape instead of a cylindrical shape, or a square prism or other prism shape. The supporting member can also be a hollow column or other prism shape.

In addition, in this embodiment, the roller axis 3 is an object for generating a load.

The main body 5c includes: a signal line guide 5f, a slit 5e, a through hole 5j (not shown in FIG. 3 ) extending in the X-axis direction, and a detection portion 5k. The detection portion 5k is composed of a gauge 5g, a fixing screw 5d, and a thin-thickness portion 5h. A pair of the detection portions 5k are provided at symmetrical positions relative to the axis 3b. In other words, a pair of the gauge 5g, the fixing screw 5d, and the thin-thickness portion 5h are provided at symmetrical positions relative to the axis 3b. The through hole 5j is used to mount the gauge 5g.

The slit 5e is composed of two first slits extending along the axis 3b and a second slit connecting the first slits. The two first slits are arranged on the extension part 5m in a symmetrical state relative to the axis 3b, and penetrate the extension part 5m in the X-axis direction. In addition, the second slit extends from the end of one of the first slits near the end of the roller axis 3 to the end of the other first slit near the end of the roller axis 3, in the vertical direction (Y-axis direction) of the axis 3b, and penetrates the extension part 5m in the X-axis direction.

A pair of signal line guides 5f are provided at symmetrical positions with respect to the axis 3b and near the fixing member end by the second slit. A thin portion 5h is formed near the end (hereinafter referred to as the "front end") of each first slit near the fixing member end and between the pair of signal line guides 5f.

FIG4 is a cross-sectional view of the B-B section in FIG3. FIG5 is a side view of the body 5c of the load detector 5 of the embodiment 1. Female threads are respectively provided in the screw holes provided on the outer side of the slit 5e in the Y-axis direction (the side away from the axis 3b), and the fixing screw 5d is inserted into the female threads. The fixing screw 5d is fixed in a state where the front end contacts the surface of the thin-thick portion 5h against the end of the slit 5e. That is, the head of the fixing screw 5d contacts the thin-thick portion 5h.

The gauge 5g is provided on the surface close to the through hole 5j end at the position opposite to the one side of the thin-thick portion 5h contacting the fixing screw 5d. More specifically, the gauge 5g is provided on the surface close to the end of the signal line guide 5f provided in the Z-axis direction at the position opposite to the one side of the thin-thick portion 5h contacting the fixing screw 5d. In addition, the through hole 5j is a hole for installing the gauge 5g as described above, and is a hole that penetrates the extension portion 5m in the X-axis direction, and the through hole 5j and the signal line guide 5f intersect at the position of the gauge 5g.

The body 5c is fixed to the fixing member 7 by the body mounting screw 6 in a manner that the straight line connecting the two gauges 5g is parallel to the load W acting on the roller. The supporting member 5b is inserted into the body 5c at any depth. After insertion, the supporting member 5b can also be fixed by screws (not shown) so that the supporting member 5b does not deviate from the body 5c in the Z direction.

The load detection method of the load detector 5 of this structure is described below using FIG3. The Z-direction distance from the front end of the slit 5e to the Z-axis center of the gauge 5g is set as L1. Also, the Z-direction distance from the front end of the slit 5e to the load W application point is set as L2.

The main body 5c which is closer to the fixing member 7 than the front end of the slit 5e can be regarded as slightly rigid. Among the roller 2a, the roller axis 3, the supporting member 5b and the main body 5c, the end closer to the supporting member 5b than the front end of the slit 5e is called the "deformation portion", and the end of the fixing member 7 is called the "fixed portion". The slit 5e is used to form the thin-thickness portion 5h, and is designed to make the rigidity of the deformable portion lower than that of the fixed portion. The deformable portion uses the resultant force W to produce bending in the Y direction. The fixing screw 5d is pressed against the thin-thickness portion 5h (the opposite surface of the gage 5g pasting surface) by the detection load F due to the bending of the deformable portion of the main body 5c.

Fig. 6 is a cantilever single beam model diagram simulating the main part of the load detector. If the structure of Fig. 3 is regarded as shown in Fig. 6, based on material mechanics, the detection load F detected by the detection part 5k is as shown in Formula 2.

[Number 2] F W

From equation 2, we know that the detection load F increases linearly with respect to L2. That is, even if the generated load W is constant, if L2 increases linearly, the detection load F will change linearly with L2.

Furthermore, FIG. 7 shows a cantilever parallel beam model diagram that simulates the main part of the load detector 5. The structure of the load detector 5 is closer to the parallel beam structure shown in FIG. 7 than the cantilever beam shown in FIG. 6. In FIG. 7, the beam 10a is equivalent to the roller 2a, the beam 10b is equivalent to the bearing and other holding parts 5a of the support member 5b, and the beams 10c and 10d are equivalent to the area from the holding part 5a of the support member 5b to the front end of the slit 5e. The beams 10c and 10d have different rigidities depending on whether the support member 5b has a body 5c facing the inside of the support member, whether the body 5c has a slit 5e, etc. Therefore, to be precise, the joint rigidity can be divided into more beams, but since the principle is the same, it is represented here by the simplified model shown in Figure 7.

The rigidity of other components 10a~10d is also different. Even the rigidity of the beam of the same component is different in the long side direction. Here, the rigidity is the product of the elastic modulus E and the secondary moment of section I of the component, which indicates the bending difficulty of the component. Depending on the rigidity of each beam, the deformation state of the beam will change. Even if it is constructed as shown in Figure 7, the detection load F can be changed linearly (at least monotonically) relative to L2.

FIG8 shows a diagram showing the position of the support member 5b of the load detector 5 changing from L2 to L2+δ. When the generated load W is less than the rated capacity of the load detector 5, the position of the support member 5b is changed in accordance with the reduction of the mating length L3 between the body 5c and the support member 5b. The detection load F' detected by the detection unit 5k is as shown in Formula 3:

[Number 3] )W=( )W

From formula 3, it can be seen that when the position of the supporting member 5b is changed from L2 to L2+δ (δ>0), the detection load F' detected by the detection part 5k is greater than the detection load F in formula 2 (when the position of the supporting member 5b is L2), which can improve the detection accuracy of the load W. In addition, when the load W acting on the roller 2a is too large, it is sufficient to increase the fitting length L3 between the main body 5c and the supporting member 5b. If the fitting length L3 of the supporting member 5b is increased, that is, the position of the supporting member 5b is changed from L2 to L2-δ, it can be seen from formula 3 that the load detected by the detection part 5k is smaller than the case where the position of the supporting member 5b is L2.

As is known, when designing a production line for conveying foil material 1, the user must estimate in advance the load W that will act on the roller 2a, and then use a load detector 5 that is as close to the load W as possible and has a rated capacity greater than the load W. Moreover, when changing the foil material 1 to be conveyed, the load W that will act must be estimated each time, and then a load detector 5 that matches the load W must be selected.

According to the load detector 5 of the embodiment 1 of the present disclosure, when the load W is smaller (or larger) than the rated capacity of the load detector 5, the apparent rated capacity can be changed by changing the Z-direction position of the supporting member 5b relative to the body 5c. In other words, by changing the Z-direction position of the supporting member 5b relative to the body 5c and changing L2, the detection load F acting on the detection portion 5k by the load W acting on the roller 2a can be changed. In this way, within the range of the apparent rated capacity that can be changed by changing L2, the load detector 5 can detect the load W without changing to a different rated capacity.

Furthermore, since the value of L2 is larger than that below L1, the effect of the change in the installation position on the detection load F can be reduced compared to changing the installation position (below L1) of the detection unit 5k. In addition, since the detection unit 5k is not moved when the load capacity is adjusted, the possibility of the detection unit 5k being damaged due to removal and installation can be reduced in this embodiment.

Furthermore, since the load is detected only when the tip of the fixing screw 5d contacts the thin-thick portion 5h, the detection portion 5k is prevented from buckling, and a high-frequency load W can be detected. Also, since the displacement of the load W is reduced, the foil 1 can be stably conveyed.

Furthermore, the load detection method of the detection part 5k is not limited to the present embodiment. For example, in FIG3 , instead of using the female thread of the fixing screw 5d and the fixing screw 5d, a strain gauge may be attached to the position where the female thread is provided. Furthermore, the load detection method of the detection part 5k is not limited to the strain gauge. Even if a button-type force gauge is used, for example, the same effect as the present embodiment can be obtained.

Furthermore, the detection part 5k may be provided with a button-type force gauge or the like, and the load may be changed by moving the mounting position of the detection part 5k in the Z direction. That is, in addition to the configuration in which L2 is variable, L1 may also be variable to adjust the detection load F. By adjusting L1 in addition to L2, the apparent rated capacity range can be expanded compared to the configuration in which only L2 can be adjusted.

Furthermore, in this embodiment, the load detector 5 is relatively symmetrical with respect to the axis 3b. Thus, the load W in the positive and negative directions of the Y axis can be detected symmetrically. In addition, since the detector can be freely arranged in the vertical direction, the ease of arrangement can be improved.

Furthermore, in this embodiment, as shown in FIG. 1 , load detectors 5 are disposed at both ends of the roller axis 3. However, the load detector 5 may be disposed only at one end of the roller axis 3, and the roller 2a and the roller axis 3 may be supported by a cantilever.

Furthermore, the load detector 5 is not necessarily symmetrical with respect to the axis 3b, and the number of detection parts 5k is not limited to implementation form 1. FIG. 9 shows a variation of the load detector 5 of implementation form 1. In FIG. 9, the load W acts only in the -Y axis direction. The slit 5n of this variation is formed by the load detector 5 to form a cantilever beam as shown in FIG. 6, and is provided so that a force can be applied to the detection part 5k by the fixing screw 5d. Only one detection part 5k of this variation may be provided. When the load W acts only in the -Y axis direction, this structure can be used. In this case, the number of detection parts 5k can be reduced, thereby reducing the number of parts.

In addition, the material of the main body 5c and the supporting member 5b is not particularly limited. For example, iron materials such as carbon steel, high-tensile steel, rolled steel, stainless steel, or structural alloy steel, as well as electroplated steel, aluminum, magnesium, titanium, brass, copper, and alloy materials based on these materials can also be used.

Furthermore, a linear guide rail that can move in the Z direction can be designed between the support member 5b and the body 5c. Also, a Z-direction groove and a recess that fits into the groove can be designed on the support member 5b and the body 5c to provide a guide effect. If such a structure is adopted, the support member 5b can be easily moved in the Z direction, and the adjustment of L2 can be made easier.

Furthermore, the support member 5b and the main body 5c can also be fixed by bolts or the like. If the bolts are used for fixing, installation and removal can be made easier. In addition, concave and convex parts can be provided in the X direction of the support member 5b and the main body 5c, and the concave and convex parts can be fixed by fitting together. If the fitting structure using the concave and convex parts is adopted, the number of parts can be reduced because bolts or the like are not required.

The configuration shown in the above embodiments is only an example of the content of this disclosure, and can also be combined with other known technologies. The combination of the above embodiments can omit or change part of the configuration without departing from the scope of the present disclosure.

Implementation form 2. This implementation form is different from implementation form 1 except that a pair of displacement thickness portions 8n are provided on the supporting member 8b. The rest is the same as implementation form 1. In this implementation form, the center of the roller 2a of the load detector 8 will not deviate from the Z-axis direction by means of a pair of displacement thickness portions 8n, so the roller 2a can be kept horizontal, thereby suppressing the deviation of the foil. In addition, the load detector 8 of implementation form 2 can also be applied to the variation described in implementation form 1.

FIG10 is a cross-sectional view of the main part of the load detector 8 of the embodiment 2 of the present disclosure. The load detector 8 is to make a portion of the support member 8b thinner, and a defective portion 9 is provided on the surface of the support member 8b. The portion where the thickness of the support member 8b is reduced by the defective portion 9 is the displacement thinning portion 8n. In FIG10, the displacement thinning portion 8n is the thickness thinning in the load W direction, and the defective portion 9 and the displacement thinning portion 8n extend in the X-axis direction, and two are provided at relatively symmetrical positions relative to the axis 3c. Here, the axis 3c is the central axis of the body 5c.

The displacement thin and thick portion 8n is provided to reduce the rigidity of the generated load W direction between the detection portion 5k and the holding portion 5a. In addition, in the present embodiment, the defective portion 9 is provided at the surface end (the end away from the axis 3c) of the support member 8b, but it may also be provided at the end of the hollow portion 4 of the support member 8b (the end into which the body 5c is inserted). Furthermore, the defective portion 9 may also be provided at both the surface end and the end of the hollow portion 4 of the support member 8b.

If the load detector 8 of this embodiment is represented by the beam model of FIG7, the displacement thickness portion 8n is equivalent to the beam 10c. The rest of the beam is the same as that of the embodiment 1. The rigidity of the displacement thickness portion 8n is smaller than the rigidity of the retaining portion 5a of the supporting member 8b. For example, the rigidity of the displacement thickness portion 8n is preferably at least 1/10 times the rigidity of the retaining portion 5a of the supporting member 5b. If the beam model shown in FIG7 is used for explanation, the rigidity is the product of the elastic modulus E of the beam and the secondary moment of section I, which means that the rigidity of the beam 10c is smaller than the rigidity of the beam 10b.

Furthermore, when the detector is in the shape of a quadrangular prism or other prism, if the width of the beam is set to b and the thickness is set to h in the beam model, the secondary moment of the beam section I is as shown in Formula 4:

[Number 4] I=

If the beam model is applied to the present embodiment, as shown in FIG10, b becomes the length of the displacement thickness portion 8n in the Z-axis direction, and h becomes the thickness in the Y-axis direction. Here, the present embodiment effectively reduces the rigidity by reducing the dimension h1 equivalent to the beam thickness h of the beam model shown in FIG7. For example, if the thickness of the displacement thickness portion 8 is set to 1/10 times that of the retaining portion 5a of the supporting member 5b, if the material (elastic modulus) is the same, the rigidity can be reduced to 1/1000 times. In addition, the difference (reduction ratio) in rigidity of the displacement thickness portion 8n relative to the retaining portion 5a is the same for the displacement thickness portion 8n above and below the axis 3c. In addition, the shape of the displacement thickness portion 8 is not particularly limited.

FIG. 11 is a diagram for explaining the behavior of the load detector 8 of the embodiment 2 when a load is applied. FIG. 11 (1) shows a state where there is no displacement thin-thickness portion 8n and no load is applied. FIG. 11 (2) shows a state where a load W is applied to the roller 2a when there is no displacement thin-thickness portion 8n. FIG. 11 (3) shows a state where a load W is applied to the roller 2a in the embodiment having a pair of displacement thin-thickness portions 8n.

Before the load is applied, as shown in FIG11(1), the center axis 3d of the roller 2a is consistent with the axis 3c of the main body 5c, but if the load W is applied, the roller 2a, the roller axis 3 or the supporting member 8b will bend as shown in FIG11(2). As a result, the center axis 3d of the roller 2a is tilted by an angle φ in the direction of the applied load W relative to the axis 3c of the main body 5c before the load W is applied. On the other hand, as shown in FIG11(3), in the case of this embodiment, because the displacement thickness portion 8n is regarded as a pair of parallel beams, the center axis 3f of the roller 2a and the axis 3c of the main body 5c of the load detector 8 are offset in the Y direction while maintaining a parallel state. Thereby, the roller 2a will not tilt, and the foil material 1 can be prevented from being deflected.

In addition, when the load detector is installed on both sides as shown in FIG. 1 of the embodiment 1, if the bearing is an automatic self-aligning bearing, the influence of the load detector tilting on the roller 2a can be eliminated. However, by designing the displacement thickness portion 8n as in the present embodiment, special parts such as automatic self-aligning bearings are not required. In addition, when only one side of the roller 2a is supported by the load detector and the automatic self-aligning bearing cannot be used, the foil 1 can also be prevented from being deviated.

FIG. 12 shows a diagram of a load-applying method for the load detector 8 of the embodiment 2. By designing the displacement thin-thickness portion 8n, the moment effect of the load W acting on the roller 2a can be almost ignored, which is equivalent to the case where the load W acts on the end of the displacement thin-thickness portion 8n near the fixing member 7. Therefore, in this embodiment, by defining L2 as not the distance between the end of the slit 5e near the fixing member 7 and the concentrated load W acting on the roller 2a, but the Z-direction distance between the end of the slit 5e near the fixing member 7 and the end of the displacement thin-thickness portion 8n near the fixing member 7, the detection load F acting on the detection portion 5k can be expressed by the same formula as Formula 2.

In addition, in this embodiment, the load W is the generated load and the roller axis 3 is the object on which the generated load acts.

In addition, the detection object of the present disclosure is not limited to the tension of the foil, and can also be used as a general load detector. The structure shown in the above implementation form is only an example of the content of the present disclosure, and can also be combined with other known technologies. The combination of the above implementation forms can omit or change part of the structure without departing from the scope of the present disclosure.

1: Foil 2,2a~2c: Roller 3: Roller axis 4: Hollow part 5,8: Load detector 5a: Holding part 5b: Support member 5c: Body 5d: Fixing screw 5e,5n: Slit 5f: Signal wire guide 5g: Gauge 5h: Thickness part 5j: Through hole 5k: Detection part 5l: Fixing part 5m: Extension part 6: Body mounting screw 7: Fixing member 8n: Displacement thickness part 9: Defective part 10a~10d: Beam F’: Detection load T: Tension force W: Resultant force

Figure 1 is a diagram of the installation structure of the load detector of the embodiment 1; Figure 2 is a cross-sectional view along the line arrow direction of the A-A line of Figure 1; Figure 3 is a cross-sectional view of the main part of the load detector of the embodiment 1; Figure 4 is a cross-sectional view of the B-B section of Figure 3; Figure 5 is a side view of the main body of the load detector of the embodiment 1; Figure 6 is a cantilever single beam model diagram imitating the main part of the load detector of the embodiment 1; Figure 7 is a cantilever parallel beam model diagram imitating the main part of the load detector of the embodiment 1; Figure 8 is a position diagram of the load detector of the embodiment 1 with the support member changed; Figure 9 is a diagram of the load detector variation example of the embodiment 1; FIG. 10 is a cross-sectional view of the main part of the load detector of embodiment 2; FIG. 11 is a diagram illustrating the behavior of the load detector of embodiment 2 when a load is applied; and FIG. 12 is a diagram showing the manner in which a load is applied to the load detector of embodiment 2.

2a: Roller

3: Roller shaft

3b: Axis

4: Hollow part

5: Load detector

5a: Holding part

5b: Supporting components

5c: ontology

5d: Fixing screws

5e: Narrow seam

5f: Signal cable guide

5g: Gauge

5h: Thin and thick part

5k: Testing Department

5l: Fixed part

5m: Extension part

6: Main body mounting screws

7:Fixed components

W: Combined force

Claims (7)

A load detector comprises: a body having a detection portion and an extension portion; the detection portion detects the load; the extension portion extends from the detection portion to directions different from the direction of the load acting on the detection portion; and a support member having a portion contacting the extension portion along the extension direction of the extension portion and a holding portion holding the object of the load, and the distance between the detection portion and the holding portion is changed by moving the extension portion along the extension direction; wherein the body and the support member are engaged in a manner that can change the engagement length. As in claim 1, the load detector, wherein the extension portion is cylindrical or prism-shaped; the support member is hollow and forms a space inside; by inserting the extension portion into the space, the support member contacts the extension portion. A load detector as claimed in claim 1 or 2, wherein the object is a roller for conveying a foil, the roller axis belonging to an axis; and the load is the resultant tensile force acting on the foil. As in claim 1, the load detector, wherein the detection portion comprises: a thin-thickness portion, a gauge in contact with the thin-thickness portion, and a fixing screw; the fixing screw is fixed with the front end in contact with the surface of the thin-thickness portion, so that the head of the fixing screw contacts the thin-thickness portion; the gauge is disposed in the thin-thickness portion and contacts a position opposite to one surface of the fixing screw. A load detector comprises: a body having a detection portion and an extension portion; the detection portion detects the load; the extension portion extends from the detection portion in a direction different from the direction in which the load acts on the detection portion; and a supporting member, which is provided with a holding portion for holding an object to be acted upon by the load in a movable manner along the extension direction of the extension portion in contact with the upper The extension part moves along the extension direction of the extension part, so that the distance between the detection part and the holding part changes; the support member is provided between the holding part and the detection part, with a first displacement thickness part having a lower rigidity in the direction of the load than that of the holding part, and further provided with a second displacement thickness part at a position symmetrical to the first displacement thickness part relative to the central axis of the cross-section center of the extension part. As in claim 5, the load detector, wherein the rigidity of the first displacement thickness portion and the second displacement thickness portion is less than 1/10 times the rigidity of the holding portion. As in claim 5 or 6, the load detector, wherein the first displacement thickness portion and the second displacement thickness portion are respectively formed by providing a defective portion on the supporting member.