JP3294334B2 - Structural deformation detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structural deformation detector for detecting deformation occurring in structures constituting various machines and devices.

[0002]

2. Description of the Related Art Various machines and devices detect deformation of the structure when the structure is used, and improve the accuracy of the machine or device based on the detected value, or weigh the contents. Detection was being performed. Such an example will be described with reference to the drawings.

FIG. 10 is a side view of a press machine. In the figure, 1 is a frame formed in a box shape as a whole, 2 is a hydraulic cylinder fixed to the bottom of the frame 1, 3 is a piston of the hydraulic cylinder 2, 4 is a hydraulic oil of the hydraulic cylinder 2, and 5 is a hydraulic oil of the piston 3. The lower plank 6 connected to the end is an upper plank connected to the upper part of the frame 1 and facing the lower plank 6. Reference numeral 7 denotes a work placed between the lower thick plate 5 and the upper thick plate 6. When the pressure oil is supplied to the hydraulic cylinder 2, the piston 3 extends upward, and the work 7 is pressed.

When the work 7 is pressed, an upward force is generated on the lower thick plate 5 and a downward reactive force is generated on the upper thick plate 6.
These forces are transmitted through the frame 1. A part of the transmission path is indicated by a chain line 8. This force is not equal between the left and right sides of the drawing, and the magnitude differs depending on each path. In particular, depending on the shape of the work and the position where the work is placed, the work may be unloaded, and accordingly, the frame 1 may be deformed unequally in the right and left directions. I do. Therefore, if the deformation of the frame 1 is detected and the correction is appropriately performed based on the detected value, it is possible to prevent the processing accuracy from lowering. For this reason, the force transmitted by attaching a strain gauge to the force transmission path 8 of the frame 1 and the deformation of the frame 1 are detected. These strain gauges are indicated by reference numerals S1 to S4.

[0005] Such a force detecting means is applied not only to a machine but also to a stationary structure. The application examples shown in FIG. 1 1. Figure 1 1 is a side view of the hopper. 9 is a hopper, 10 is a support column of the hopper 9, and 11 is a table. Strain gauges S are attached to appropriate positions of the support columns 10, and the strain gauges S detect the deformation of the support columns 10 due to the weight of the hopper and the stored items, and determine the weight of the stored items based on the detected values. You can know.

The detection of deformation by the strain gauge S is as follows.
Since the deformation is extremely small, it is difficult to detect satisfactory accuracy, and a higher-precision detector is required. Such a detector is disclosed in Japanese Patent Application No. 1-234 filed by the present applicant.
No. 428. The outline of this detector will be described with reference to the drawings.

[0007] Figure 1 2 is a plan view of a conventional deformable detector. In the figure, 1 is the frame shown in FIG. 11 is the first
Fixed body 1 fixed to the frame 1
1a, bolts 11b1, 11b for fixing the fixing portion 11a
2 and an extension 11c. Reference numeral 12 denotes a second block body provided to face the first block body 11, and includes a fixed portion 12a fixed to the frame 1, bolts 12b1 and 12b2 for fixing the fixed portion 12a, and an extended portion 12c. I have. Each of the extension portions 11c and 12c is opposed to each other and extends in parallel, and is a free end with respect to the frame 1. 13a, 13b are each extension 11
c, a thin plate that joins between 12c up and down,
They are parallel to each other. 14 is a thin shear plate connected between the extension parts 11c and 12c, and 15a and 15b are strain gauges.

When a force is transmitted to the frame 1, the frame 1 undergoes expansion and contraction, and a relative displacement occurs between the extension portions 11c and 12c, thereby causing the flat plates 13a and 13b and the shear plate 1 to move.
4 is deformed. According to this deformation, the strain gauge 15a,
Elongation and contraction occur in 15b, so that a signal proportional to the deformation can be obtained. That is, the deformation is taken out as a displacement of the distance h between the fixing portions 11a and 12a.

[0009]

In the press machine as described above, the frame 1 has a symmetrical shape on the left and right, and its deformation is almost caused by a force. Therefore, the overall deformation is a relatively small deformation. However, in other machines, the overall deformation is not very small as in a press machine, and may cause considerable deformation. This will be described using a machining center as an example.

[0010] Figure 1 3 is a side view of the machining center, it is drawn extremely exaggerated deformation occurring during use.
In the figure, reference numeral 20 denotes a machining center. 21 is the base,
22 is a column, 23 is a head, 24 is a feed stand, and 25 is a fixture. 26 is a motor installed on the head 23,
Reference numeral 27 denotes a tool rotated by a motor 26 via a speed reducer, and reference numeral 28 denotes a work fixed to the fixture 25 and cut by the tool 27.

In the machining center 20, during machining of the work 28, the machining reaction force from the tool 27 is applied to the head 23.
The reaction force from the work 28 is transmitted to the column 22 through the base 21.
Furthermore, in addition to these forces, a large amount of heat is generated by the motor 26, and this heat flows from the head 23 to the column 22.

In this case, the heat transmitted is relatively proportional to the distance of the transmission path, and the head 23 has an outer portion 23a.
And the inside portion 23b is small, and in the column 22, the outside portion 22a is small and the inside portion 22b is large.

In addition to these forces and heat, the machining center 2
0 cantilever shape, room temperature difference, machining center 2
The position of a controller (heat source) (not shown), 0, etc., affects the column 22 and the head 23, causing large overall deformation as shown in the example shown. As a result, an error occurs in the position and orientation of the tool 27, and high-precision machining becomes impossible. Therefore,
Such deformation is detected, and the tool 2 is determined based on the detected value.
It is necessary to correct the position and orientation of 7 correctly. In this case, it is possible to detect the deformation by using a modified detector shown in FIG. 1 2, a large number points to the deformation detector for overall large deformation as shown in FIG. 1 3 This requires not only a lot of labor and time, but also the use of a large number of deformation detectors increases the cost required for the installation, and the signal from the large number of deformation detectors A complicated system for determining the overall deformation on the basis of this is required, and the cost for that is also increased.

An object of the present invention is to solve the above-mentioned problems in the prior art, and to provide a structural deformation detector capable of detecting a deformation without attaching a large number of detectors even when the whole is large. Is to do.

[0015]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is directed to a method of detecting a deformation of a structure by attaching the structure to a structure which is deformed by transmitting at least one of a force and a temperature. A first point and a second point set on the surface of the structure.
A rod disposed along a line connecting the points, a fixing means for fixing one end of the rod to the first point, and a second end of the rod fixed to the second point And a detector that holds the portion and allows only the movement in the axial direction substantially to suppress the movement in the other direction, and detects the amount of displacement of the other end of the rod with a detector. A plurality of spring plates formed integrally with the rod body and provided in parallel with a plane perpendicular to the long axis of the rod body hold the other end of the rod body and substantially extend in the axial direction thereof. In this case, only the movement is allowed, and the movement in the other direction is suppressed. For example, the detector is attached to the spring plate.

[0016]

When a deformation occurs between a first point and a second point on the surface of a structure, a distance between the first point and the second point changes, and accordingly, a rod is formed.
The other end portion of the displaced. Double This displacement pairs of detector
Due to the functions of the number of leaf springs, they occur only in the direction of the line connecting the first point and the second point. The detector detects the displacement of the other end of the rod. Since rod is used in the displacement of the detection of the present invention, it is possible to set large the first point and the distance between the second point, thereby, the overall large deformation, numerous variations detector Can be easily detected without the use of

[0017]

EXAMPLES Hereinafter, the embodiments of the present invention will be described with reference to FIG surface. FIG. 1 is a side view of a structural deformation detector according to a reference example of the present invention. In FIG, 30 is a structure, FIG. 10,
Frame 1, the support posts 10 shown in FIG. 1 1 shown in FIG. 1 2, column 22 shown in FIG. 12, corresponds to the head 23. P1 indicates an arbitrary point (hereinafter referred to as a reference point) set on the surface of the structure 30, and P2 indicates another arbitrary point (reference point) similarly set on the surface of the structure 30. 31 is a fixing member fixed to the structure 30 at the reference point P1. Reference numeral 32 denotes a rod arranged along a line connecting the reference points P1 and P2, and one end thereof is fixed to the fixing member 31.

Reference numeral 33 denotes a sensor which is disposed to face the other end of the rod 32 and detects the displacement of the other end.
The sensor 33 includes a non-contact type sensor, for example, a capacitance type sensor, an eddy current type sensor, a sensor using light reflection,
A known sensor such as a differential transformer is used. Reference numeral 34 denotes a support member for supporting the sensor 33, which is fixed to the structure 30 at a reference point P2. Reference numeral 35 denotes a restricting means for restricting the movement of the rod 32, which has a function of permitting only the axial movement of the rod 32 and suppressing the movement in other directions.

[0019] In this reference example, restricting means 35, the structure 3
0, and the support 35a
Bearing 35b for contacting and inserting the rod 32
It is composed of For example, white metal, a bearing, or the like is used for the slide bearing 35b.

The fixing member 31, the rod 32, the sensor 3
3, the displacement detector 36 of the present embodiment is constituted by a support member 34 and the restricting means 35.

[0021] Next, the operation of the present embodiment. Now, it is assumed to apply a displacement detector 36 to the column 22 of the machining center 20 shown in FIG 3. As described above, during operation of the machining center 20, the column 22 is generally greatly deformed as shown in FIG. 1 3 by the force and heat are transmitted. Therefore, the displacement detector 36 is installed by setting the reference points P1 and P2 shown in FIG. 1 so that the interval H between them becomes longer in the vertical direction of the column 22. In this case, the rod 32
Also, a length close to the interval H is used.

When the machining center 20 is operated and the column 22 is deformed, the rod 32 is displaced accordingly. At this time, the rod 3
2 is displaced only in its axial direction and not in the other direction.
Since the displacement of the rod 32 is the sum of the displacements occurring in the respective portions during the interval H, the displacement of the tip of the rod 32 (the portion facing the sensor 33) is a large value. That is,
The displacement of the tip of the rod 32 is significantly larger than the displacement of the structure 30 facing the tip of the rod 32, and the displacement is enlarged. The enlarged displacement amount is detected by the sensor 33, and an appropriate posture correction is performed based on the detected displacement amount. As a result, the position and posture of the tool 27 are accurately held, and high-precision machining is performed. It will be implemented reliably.

FIG. 2 is a partially broken side view showing another specific example of the restricting means 35 shown in FIG. In this figure, the same or equivalent parts as those shown in FIG. 1 are denoted by the same reference numerals.
In this specific example, the support 35 a is formed integrally with the support member 34. Further, a bearing is shown as the slide bearing 35b. By forming the support 35a integrally with the support member 34, the support 35a is
It is possible to save the trouble of adjustment when attaching to zero. Note that the support 35 a can be attached to the outer wall of the sensor 33 instead of the support member 34.

[0024] Thus, in this reference example, since to use a rod 32, 1 also to the overall large displacement
It is only necessary to install one deformation detector 36, and it is possible to save the labor and time for installing a large number of deformation detectors in the related art and the cost of the deformation detector itself, and
Since it is not necessary to construct a complicated system required for processing the detection signals of the large number of deformation detectors, it is possible to eliminate the cost for this. In addition, since an enlarged displacement occurs at the tip of the rod 32, highly accurate detection can be performed.

[0025] FIG. 3 is a side view of a modified detector according to another exemplary embodiment of the present invention. In the figure, the same or equivalent parts as those shown in FIG. 1 are denoted by the same reference numerals. In the reference example shown in FIG. 1, a sliding bearing 35b is used for the regulating means 35. However, in this reference example, the sliding bearing 35b is not used.
The rod 32 is fixed to a regulating means having two mutually parallel spring plates 35c. That is, the rod 32 is fixed to the tip of the support 35a, and each spring plate 35c is formed on a part of the support 35a (between the fixed portion of the rod 32 and the support member 34). In other words, the rod 32 is fixed to the support 35a via each spring plate 35c. When the rod 32 is displaced, each spring plate 35c bends, and the rod 32
Can be displaced without hindrance. In this case, since there are two parallel spring plates 35c, there is almost no displacement (tilt) in the other direction of the rod 32.

[0026] In the case of the present embodiment, although the support 35a is formed integrally with the support member 34, the support 35
a may be fixed to the structure 30 or to the outer wall of the sensor 33. The number of the spring plates 35c may be one instead of two, or three or more may be provided in parallel with each other.

FIG. 4 is a side view showing an example of the detector according to the embodiment of the present invention . In the figure, the same or equivalent parts as those shown in FIG. 3 are denoted by the same reference numerals. In the example shown in FIG. 3, the mutually parallel spring plates 35 c are provided on one side of the rod 32.
Only one set is provided, but in this embodiment , two sets are provided, one set on each side of the fixed portion of the rod 32.
Thus, when the rod 32 is displaced, displacement in other directions is completely restricted.

The support 35a can be fixed to either the support member 34 or the structure 30 while maintaining the positional relationship between the two sets of spring plates 35c with respect to the fixed portion of the rod 32. . Further, the number of spring plates 35c in each set may be one or three or more. Other effects of this embodiment
This is the same as the effect of the reference example shown in FIG.

In the embodiment shown in FIG. 4, the displacement of the tip of the rod 32 is determined by the sensor 3 supported by the support member 34.
3 has been described. However, the sensor 33
Is fixed to the tip of the rod 32, the displacement of the tip of the rod 32 can be detected. That is, the sensor 33 is fixed to the tip of the rod 32, and an appropriate member is fixed to the reference point P2, and the displacement of the sensor 33 with respect to this member (the same displacement as the displacement of the tip of the rod 32) is detected by the sensor 33. You can also. In this case, it is possible to use the same sensor 33 as those used in the real施例.

FIG. 5 is a side view of a detection member according to another embodiment of the present invention. In the figure, the same parts as those shown in FIG. 1 are denoted by the same reference numerals. Sensor supported by the support member 34 38, 37 rod 3 is fixed to the sensor 3 8
2 is a fixing part for fixing the fixing member 2. The sensor 38 detects the amount of displacement of the rod 32 and also has the function of the restricting means 35 in each embodiment described above, as described later. Further, while the sensor 33 in each of the above embodiments is of a non-contact type, the rod body 32 is connected to the sensor 38 of this embodiment via a fixing portion 37, and in that sense, the sensor 38 of this embodiment is Sensor 3
8 is a contact type.

A side view of a specific example of the sensor 38 of this embodiment is shown in FIG.
Further described with reference to FIGS. 6 and 7 show. FIG.
38a is a first connecting portion connected to the fixing portion 37 shown in FIG. 5, 38b is a second connecting portion connected to the support member 34, and 38c is the first connecting portion 38a and the second connecting portion. 38b
And two sets of spring plates interposed therebetween. Each spring plate 38c
Is composed of two parallel spring plates, like the two sets of spring plates 35c shown in FIG. 38d is a core fixed to the first connecting portion 38a, 38e is a second connecting portion 38
The coil fixed to b.

When the rod 32 is displaced, the displacement is transmitted to the first connecting portion 38a via the fixing portion 37, and the core 38
By displacing d by the same amount, the amount of insertion of the core 38d into the coil 38e is changed, whereby a voltage proportional to the displacement can be taken out from the coil 38e. in this case,
The displacement of the first connecting portion 38a and, consequently, the displacement of the core 38d are completely regulated only in a predetermined direction by the two sets of spring plates 38c.

FIG. 7 shows another specific example of the sensor 38, and the same parts as those in FIG. 6 are denoted by the same reference numerals. S is a strain gauge attached to an end of each spring plate 38c of each set.
As in the specific example shown in FIG. 6, when the rod 32 is displaced, the displacement is transmitted to the first connecting portion 38a via the fixing portion 37. The displacement of the first connecting portion 38a is controlled by each spring plate 38c.
And the magnitude of this deflection is taken out as a change in the resistance value of the strain gauge S (proportional to the amount of displacement).

FIG. 8 shows a device similar to the sensor 38 of this embodiment .
It is a side view which shows the reference example which had the function . In the figure, the same parts as those in FIG. 5 are denoted by the same reference numerals. 38f is a ring-shaped spring body, and S is a strain gauge attached to the front and back of the spring body 38f to face each other in a direction orthogonal to the axial direction of the rod 32. The spring body 38f is deformed by the displacement of the rod 32, and accordingly the strain gauge S is distorted, and its resistance is changed. The change in the resistance is taken out as the displacement of the rod 32. In this specific example, the spring body 38
f does not directly regulate lateral movement in the figure,
Overall results of the same like effects as those regulating the movement.

FIG. 9 shows another reference example of the sensor 38, and the same parts as those in FIG. 5 are denoted by the same reference numerals. 38g
Is a semicircular spring body, and S is a strain gauge attached to the front and back of a predetermined portion of the spring body 38g. Operation of this reference example is the same as the operation of the reference example shown in FIG. Also, the spring plate 38
g has almost the same function as the spring body 38f .

In each of the above embodiments, the rod 32 is made of the same material as that of the structure 30 or a material having a similar coefficient of thermal expansion, and the rod 32 is enclosed with the structure 30 by a cover. For example, only deformation due to force can be detected, and if a material having a thermal expansion coefficient close to 0 (for example, an Invar alloy) is used, deformation due to both force and heat can be detected. Furthermore, in the above Description has been described an example of applying the deformation detector machining center, a frame of the press machine, the support posts of the hopper, it is clear is applicable to various other structures.

[0037]

As described above, according to the present invention, one end of the rod is fixed to the first point of the structure, and the rod is fixed to the second point.
Of the detected object, parallel to the plane perpendicular to the long axis of the rod
The other end of the rod is held by a plurality of spring plates ,
Allows only axial movement of the body and inhibits movement in other directions
At the same time, the displacement of the other end of the rod is detected by a detector, so movements other than the axial direction of the rod can be suppressed with a simple configuration.
Therefore, only one deformation detector needs to be installed for a large displacement as a whole, and the labor and time required for installing many conventional deformation detectors, and the cost and system of the many deformation detectors themselves. Costs for construction can be saved. Also, since an enlarged displacement occurs at the tip of the rod,
Highly accurate detection can be performed.

[Brief description of the drawings]

FIG. 1 is a side view of a structural deformation detector according to a reference example.

FIG. 2 is a side view of a specific example of the restricting means shown in FIG.

FIG. 3 is a side view of a structural deformation detector according to another reference example.

FIG. 4 is a side view showing an example of a detector according to the embodiment of the present invention.

FIG. 5 is a side view of a detection body according to another embodiment of the present invention.

6 is a side view of a specific example of the sensor shown in FIG.

FIG. 7 is a side view of another specific example of the sensor shown in FIG.

FIG. 8 is a side view of a specific example of the sensor according to the reference example.

FIG. 9 is a side view of another specific example of the sensor according to the reference example.

FIG. 10 is a side view of the press machine.

FIG. 11 is a side view of the hopper.

FIG. 12 is a plan view of a conventional deformation detector.

FIG. 13 is a side view of the machining center.

[Explanation of symbols]

 Reference Signs List 30 structure 31 fixing member 32 rod 33 sensor 34 support member 35 regulating means

Claims (4)

(57) [Claims] 1. A deformation detector for a structure, which is attached to a structure that is deformed by transmitting at least one of a force and a temperature and detects deformation of the structure, set on a surface of the structure. The first point and the second
A rod disposed along a line connecting the points, a fixing means for fixing one end of the rod to the first point, and a second end of the rod fixed to the second point And a detector that holds the portion and allows only the movement in the axial direction substantially to suppress the movement in the other direction, and detects the amount of displacement of the other end of the rod with a detector. A plurality of spring plates formed integrally with the rod body and provided in parallel with a plane perpendicular to the long axis of the rod body hold the other end of the rod body and substantially extend in the axial direction thereof. A structural deformation detector characterized in that only movement is allowed and movement in other directions is suppressed. 2. The structural deformation detector according to claim 1, wherein the detector is attached to a spring plate. 3. The structure deformation detector according to claim 1, wherein the rod is made of a material having a coefficient of thermal expansion equal to or close to that of the structure. 4. The structural deformation detector according to claim 1, wherein the rod is made of a material having a thermal expansion coefficient of almost zero.