JP2008002931A - Device for measuring inter-hole distance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and accurately measure the interval between both through-holes formed in a measuring object by a single operator. <P>SOLUTION: A device for measuring an inter-hole distance is constituted of a measuring point setting means 11 having a shaft 12 inserted into through-holes 6-8 mainly constituting a boss part, a measuring point setting means 21 mainly inserted into through-holes 9a, 10a of brackets 9, 10, and a measure 30. Each of shafts 12, 22 has the same length, and centering members 13, 23 on which four-spot conical curved surfaces 13a, 23a and notched parts 13b, 23b are formed alternately are mounted mutually oppositely on two spots on each shaft 12, 22, and each shaft 12, 22 is centered by action of each conical curved surface 13a, 23a. The measure 30 is held fixedly on both end faces of one side and the other side of each shaft 12, 22 inserted into each of boss parts or a both part and the through-hole, and the distance between them is measured. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an inter-hole distance measuring device for measuring a distance between through holes in a measured object having at least a pair of through holes such as bosses through which pins are inserted.

  For example, a hydraulic excavator as a construction machine that performs excavation work of earth and sand includes excavation work means including a boom, an arm, and a bucket. The boom and arm are provided with connecting pin mounting portions at a plurality of locations. For example, a boss portion is formed at an end portion or a position in the vicinity of the end portion of the arm, and a connecting pin is attached to the boss portion so that a boom and a bucket are connected so as to be relatively rotatable. Further, a bracket is provided at a predetermined position, and a through hole is formed in the bracket to form a connecting portion for a cylinder tube and a rod constituting the hydraulic cylinder.

Here, a structural member such as a boom or an arm, for example, an arm is configured by a can assembly structure in which a steel plate having a predetermined shape such as a flat plate or a bent plate is assembled by welding means, as shown in Patent Document 1. The A connecting member having a boss portion is connected to the can assembly structure member by welding means. Furthermore, members such as a bracket having a connecting portion of a hydraulic cylinder and a reinforcing plate are also welded if necessary. As described above, the structural member constituting the arm is provided with the connecting portion to the boom and the bucket and the mounting portion of the hydraulic cylinder, and each of the mounting portions has a through hole.
JP 2005-29984 A

  By the way, in the structural member mentioned above, since assembly is mainly performed by welding including attachment of a can assembly and a bracket, there is a possibility that contraction, bending, deformation or the like of each part may occur due to the action of heat generated during welding. Therefore, even if the dimensions of parts made of members such as steel plates in each part are formed with high accuracy, the assembly accuracy cannot be maintained due to deformation or the like that occurs during welding. In particular, the position and state of each of the above-mentioned through holes are extremely important. May be impaired.

  Therefore, it is possible to predict the deformation of each component member that occurs during welding, anticipate the positional deviation of these through-hole forming portions in advance, and perform the manufacture, assembly, processing of the through-holes, etc. of the respective components. The assembly accuracy of the member itself can be increased. In this manner, detection of misalignment or deformation during welding can be performed with reference to through holes formed in various places such as an arm and a boom. That is, by measuring the distance between two through holes in a predetermined member, it is possible to detect the degree of deformation during welding with respect to the original design value. There are various methods for measuring the distance between the two through holes, and whatever the method is used, the center position of each through hole must be detected.

  It is often difficult to accurately detect the center position of each of the above-mentioned through holes. If the distance between the two through holes is short, a measure is passed between the two through holes. The distance between holes can be measured by any worker, but at least two workers are required to pass the measure between the two through holes, especially for large members such as hydraulic excavator arms and booms. It becomes. Moreover, since the structural member has a box shape, in order to perform the measurement with high accuracy, in the through hole formed at two locations, not only the distance between the openings to the wall surface on one side is measured, It is necessary to measure the distance between the openings on the other wall surface, and there is a possibility that the reliability with respect to the measurement accuracy on these openings cannot be sufficiently obtained.

  The present invention has been made in view of the above points, and an object of the present invention is to make it possible to measure the interval between two through holes formed in a structural member very easily and accurately. There is.

  In order to achieve the above-described object, the present invention provides an inter-hole distance measurement for measuring the distance from the center of one through hole to the center of the other through hole for an object having at least a pair of through holes. An apparatus comprising: a shaft that can be inserted into the through hole; a centering member that is fitted to the shaft and has at least three conical curved surfaces formed on an outer surface; and the centering member that is attached to the shaft. A measuring point setting means having a fixing means fixed at an arbitrary position in the axial direction, and the measuring point setting means are respectively attached to the pair of through holes, and the end faces of the shafts of both the measuring point setting means It is characterized by comprising distance measuring means for measuring the distance between the center positions.

  Here, the object to be measured can be the above-described hydraulic excavator arm or boom, but the inter-hole distance measuring device according to the present invention is not limited to this. In short, the present invention can be applied to various structural members, particularly large structural members that cannot be measured by one person, provided with a plurality of through holes including a boss portion. And it applies especially suitably, when a deformation | transformation of a member arises from the relationship assembled by a welding means like a can assembly structure.

  In a can assembly structure member assembled by welding, deformation such as bending or twisting may occur due to heat during welding. In this can assembly structure member, there is a certain amount of space between the opening portions at both ends of the boss portion and other through holes. Therefore, the shaft is inserted into the through hole, and a pair of centering members are fitted into the shaft from both sides of the through hole, and the shaft can be centered with respect to the through hole by these centering members. In order to stably fix the shaft to the centering member in this state, at least one flat surface portion is formed on the outer surface of the shaft, and the centering member is fixed to the flat surface portion of the shaft by a set screw. it can. The centering member is formed with a conical curved surface, and a portion between the adjacent conical curved surfaces is a notch. That is, the centering member is formed of a truncated cone-shaped member having a bottom surface larger in diameter than the through-hole and a small-diameter side end surface smaller than the through-hole, and is cut into a conical curved side surface at regular intervals. A notch is formed. At least three conical curved surfaces are provided in the circumferential direction, but it is desirable to form four conical curved surfaces from the viewpoint of ease of manufacture. Further, it is desirable that the width of the conical curved surface be as narrow as possible on condition that the conical curved surface is stably held when fitted into the through hole. As a result, even if there are some errors in the dimensions of the through holes, and even if the through hole forming part in the plate material such as a steel plate constituting the structural member or the vicinity thereof is deformed by the action of heat, that is, Regardless of the state of the through-hole, it becomes possible to detect a position that is substantially centered in the through-hole.

  As a distance measuring means for measuring the distance between two shafts mounted at the center position of the through hole by a centering member, a measure that is detachably fixed to the end face of one shaft and can extend to the end face of the other shaft. Can be configured. In addition, a pinpoint conductive contact portion is provided at the center position of the ends of both shafts, a wire is provided between these contact portions, and a constant current is passed between the wires. The distance between the shafts can also be measured based on the ratio between the measured voltage and the reference voltage, with the voltage value per unit length as the reference voltage. Further, it is also possible to employ a technique in which a point light source composed of a light emitting diode or the like is disposed at the center position at the end of each shaft, and the distance between these light sources is measured by triangulation.

  By comprising in this way, the distance between holes in a can-assembled structure can be easily and accurately measured by a single operator.

    Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, FIG.1 and FIG.2 shows the structure of the arm main body structural member 1 in the arm in the working means of a hydraulic excavator as an example of a can assembly structure. The object to be measured to which the inter-hole distance measuring device of the present invention is applied is not limited to the arm main body structural member 1.

  In these drawings, the arm main body structural member 1 has a can assembly structure composed of left and right side plates 2, 2, an upper plate 3, a lower plate 4, and a bending plate 5. Each of these members is composed of a plate body such as a steel plate and is assembled so as to be connected to each other by welding means. Further, the can assembly structure member is provided with a through hole 6 constituting a boss portion for connection to the bucket and a through hole 7 constituting a boss portion for connection to the link member on one end side by welding means. ing. Further, a through-hole 8 constituting a boss part for connection to the boom is attached by welding means at the position of the connection part between the lower plate 4 and the bending plate 5 in the vicinity of the other end. Furthermore, a pair of brackets 9, 9 are welded to the upper plate 3, and through holes 9 a are formed in these brackets 9, and a pair of brackets 10, 10 are also welded to the bending plate 5. These brackets 10 also have through holes 10a. The through holes 9a and 10a are fitted with connecting pins that are connected to the tip of the rod of the hydraulic cylinder or the base end of the cylinder tube.

  Although the arm body structural member 1 is configured as described above, each part constituting the arm body structural member 1 is assembled by welding means, and the assembly accuracy of each part such as deformation due to the influence of heat generated during welding. May cause errors. If such an error occurs, the smoothness of the operation will be impaired when the arm or bucket is connected and the hydraulic cylinder for driving is mounted. Therefore, when manufacturing and assembling each part, the error due to deformation is expected in advance. Therefore, the accuracy in the assembled state can be improved. Here, in mass production, if the material of each part constituting the arm body structural member 1 is constant, all the dimensional relationships are the same, and all are welded under the same conditions, it is obvious that there is an error with respect to the design value. Is almost constant.

  In view of the above, in the stage before mass production of the arm body structural member 1, a plurality of prototypes are manufactured, the dimensions of each part after the manufacture are measured, and each part is corrected so as to correct errors occurring during assembly. By adjusting the dimensions and assembly conditions, the error at the time of welding is corrected, and the highly accurate arm main body structural member 1 can be manufactured. Therefore, it is necessary to measure the dimensional accuracy of each part in the prototype described above. Here, the most important dimensional accuracy as the arm main body structural member 1 is the position and the axial center of each of the through holes 6 to 8, 9 a, and 10 a described above. For this purpose, the positional relationship between these through holes 6 to 8, 9 a and 10 a is measured.

  For this purpose, as shown in FIG. 3 to FIG. 8, a measurement point setting means constituting the inter-hole distance measuring apparatus is used. Therefore, the configuration of the measurement point setting unit will be described below. FIGS. 3 to 5 show a measuring point setting means 11 for a large diameter, and FIGS. 6 to 8 show a measuring point setting means 21 for a small diameter.

  First, in FIGS. 3 to 5, reference numeral 12 denotes a metal shaft. The shaft 12 has a round bar shape, and a flat surface portion 12a having a predetermined width from both ends toward the center on the side surface. , 12a are formed. A centering member 13 is fitted on the shaft 12. The centering member 13 is a substantially frustoconical member provided with a through hole 14 having a hole diameter substantially equal to the outer diameter of the shaft 12 at the center, and four conical curved surfaces 13a are formed every 90 degrees in the circumferential direction. The part between these conical curved surfaces 13a, 13a adjacent to each other is a notch 13b. Further, a collar portion 15 is connected to the bottom surface portion of the centering member 13, that is, the maximum diameter portion, and the centering member 13 is fixed to the collar portion 15 at an arbitrary position in the axial direction of the shaft 12. A stopper screw 16 as a fixing means is screwed.

  The stopper screw 16 is composed of a wing screw, and its tip has a planar shape. Therefore, when the stopper screw 16 is tightened, the centering member 13 is fixed so as not to move in the axial direction by pressing the tip thereof against the flat surface portion 12a of the shaft 12 without using a special tool. The That is, the centering member 13 is fitted from both ends of the shaft 12 and can be fixed at a desired position in the axial direction of the shaft 12 by the stopper screw 16. A semicircular stepped portion 17 is formed at both ends of the shaft 12, and a clamp magnet 18 is used as a means for detachably fixing a measure 30 (described later) to the vertical wall of the stepped portion 17. Can be detachably mounted.

  The through holes 6 to 8 constituting the boss portion provided in the arm main body structural member 1 have a large diameter, and are connected to the bucket, the link member, and the boom so as to be relatively rotatable by pins. It is. The through holes 9a and 10a provided in the brackets 9 and 10 have a smaller diameter than the through holes 6 to 8, and the ends of the hydraulic cylinders are connected to each other so as to be relatively rotatable using pins. If the centering member 13 constituting the measurement point setting means 11 can be attached to the large-diameter through holes 6 to 8 and the small-diameter through holes 9a and 10a, the centering member 13 becomes large and heavy, and the bracket 9, The distance between 9 and the distance between 10 and 10 is narrower than the distance between the side plates 2 and 2 constituting the boss portion, and it is necessary to allow both centering members to be inserted into the through holes without interfering with each other. . Therefore, as the measurement point setting means 21 attached to the through holes 9a and 10a having a small diameter, a centering member 23 having a small size is used as shown in FIGS. However, the measurement point setting means 11 and the measurement point setting means 21 have similar shapes, at least with the difference in the size of the centering member. The shaft 12 and the shaft 22 are at least the same length. The thickness may be the same, and the small-diameter shaft 22 can be made thinner. The shaft 22 is formed with a flat surface portion 22a, the centering member 23 is formed with four conical curved surfaces 23a and cutout portions 23b alternately, and the outer diameter of the shaft 22 is formed at the center thereof. The centering member 23 is fixed to an arbitrary position of the shaft 22 by a stopper screw 26 attached to the collar portion 25. Furthermore, a semicircular step 27 is formed at both ends of the shaft 22, and a magnet 28 that is attached to and detached from the vertical wall is provided.

  For example, when measuring the distance between the large-diameter through-hole 6 and the large-diameter through-hole 8, as shown in FIG. 8 and measure the distance between them. When measuring the distance between the through-hole 6 and the small-diameter through-hole 9a of the bracket 9, as shown in FIG. The measurement point setting means 21 for a small diameter is attached to the through hole 9a. The distance between these two points is measured. As the distance measuring means, for example, a measure 30 can be used. In addition, this distance is measured on both sides of the arm body structural member 1.

  First, the shaft 12 from which the centering member 13 is detached is inserted into the through holes 6 formed in the both side plates 2 and 2. And the length of the protrusion part to the right and left from the both ends of the through-hole 6 is made substantially equal. Next, a pair of centering members 13 are inserted from both ends of the shaft 12 inserted through the through-hole 6 in this way toward both side plates 2 and 2. Here, the centering member 13 is fitted to the shaft 12 so that the diameter-reduced portion side faces the side plate 2, and the conical curved surface 13 a of the centering member 13 is brought into contact with the edge portion of the through hole 6. Here, since the conical curved surface 13a is provided at four places, when the centering member 13 is pushed in from both sides toward the inside of the through hole 6, the center of the centering member 13 becomes the center position of the hole diameter of the through hole 6. Self-aligning is performed so as to match, and the shaft 12 is disposed at the axial center position of the through hole 6. In this state, the stopper screw 16 is screwed into the centering member 13, whereby the tip of the stopper screw 16 is brought into pressure contact with the flat surface portion 12 a of the shaft 12, and the centering member 13 is fixed to the shaft 12.

  The measurement point setting means 11 is also attached to the through-hole 8 by the same method. Then, for example, one end of the measure 30 is brought into contact with the stepped portion 17 formed on the end surface of the shaft 12 in the measurement point setting means 11 attached to the through-hole 6, and one end of the measure 30 is used by using the magnet 18 as a fixing means. Fix the part. Then, the distance between the through holes 6-8 is obtained by pressing the other end of the measure 30 against the position of the stepped portion 17 on the end surface of the shaft 12 constituting the measurement point setting means 11 mounted on the through hole 8 and reading the scale. Is measured. Here, in order to accurately measure the distance, the protruding lengths of the shaft 12 mounted in the through hole 6 and the shaft 12 mounted in the through hole 8 from the side plate 2 are made equal. The amount of protrusion of the shaft 12 can be roughly determined by measurement and can be measured by a measure, but if the shaft 12 is provided with a scale, the amount of protrusion to both sides can be detected more accurately and easily. Further, since the shaft 12 is aligned with the center position between the through holes 6 and 8, and the semicircular stepped portion 17 is formed on the end surface of the shaft 12, the shaft center position of the shaft 12 can be easily detected. Thus, the distance between the center positions of the through hole 6 and the through hole 8 can be accurately measured. And since an operator does not need to hold | maintain one edge part of the measure 30, it can measure this distance easily. As a means for detachably fixing the end portion of the measure 30, an appropriate fixing means such as a butterfly bolt may be used instead of the clamp magnet 18.

  Here, as long as the centering member 13 is partially inserted, even if the hole diameters of the through holes 6 and 8 are different, the center position of the through holes 6 and 8 can be reliably detected by the measurement point setting means 11. Can do. That is, the shaft 12 is arranged at the center position of the through hole, and the centering member 13 exhibits a function for centering the shaft 12 regardless of the size of the through hole. Therefore, even if the hole diameters of the through hole 6 and the through hole 8 are different, and there is some variation in the processing accuracy in the through holes 6 and 8, the center position of the shaft 12 is substantially the through hole 6. , 8 at the center position. For this reason, the distance between the holes can be measured very accurately and easily by spanning between the center positions of the two shafts 12 and 12 with the measure 30.

  Since both ends of the shaft 12 inserted through the two portions protrude from both sides of the through holes 6 and 8, that is, from both side plates 2 and 2, substantially the same length, the arm body structural member in the through holes 6 and 8 The distance between the opening ends on both sides of the left and right side plates 2 can be measured. As a result, the distance between the center positions of the through-hole 6 and the through-hole 8 can be accurately measured at the openings on both sides, and based on this measurement value, the through-holes 6 and 8 in the arm body structural member 1 are measured. It is also possible to detect the presence or absence of deformation such as bending, warping, twisting, and distortion of the intervening parts.

  Further, as shown in FIG. 10, in order to measure the distance between the through hole 6 and the through hole 9a of the bracket 9, the measurement point setting means 21 is attached to the through hole 9a. The mounting method of the measuring point setting means 21 and the distance measurement between the measuring point setting means 21 and the measuring point setting means 11 mounted in the through hole 6 can be performed in the same manner as described above. Here, between the width dimension of the through-hole 6 and the distance between the pair of brackets 9 and 9, the distance between the brackets 9 and 9 is shorter, but the length dimension of the shaft 22 of the measuring point setting means 21 is measured. Since it is the same as the shaft 12 of the point setting means 11, the linear distance between the center of the through-hole 6 and the center of the through-hole 9a can be measured.

It is a front view of an arm main body structural member. It is a top view of FIG. It is a front view of the measuring point setting means for large apertures. It is XX sectional drawing of FIG. FIG. 4 is a side view of FIG. 3. It is a front view of the measurement point setting means for small apertures. It is YY sectional drawing of FIG. FIG. 7 is a side view of FIG. 6. It is explanatory drawing which shows the state which is measuring the distance between a boss | hub part and a boss | hub part. It is explanatory drawing which shows the state which is measuring the distance between a boss | hub part and a through-hole.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Arm main body structural member 2 Side plate 3 Upper plate 4 Lower plate 5 Bending plate 6-8 Boss hole 9 and 10 Bracket 9a, 10a Through hole 11 Measuring point setting means 21 for large diameter Measuring point setting for small diameter Means 12, 22 Shafts 12a, 22a Flat surface portions 13, 23 Centering members 13a, 23a Conical curved surfaces 16, 26 Stopper screws 18, 28 Magnet 30 Measure

Claims (3)

In the inter-hole distance measuring device that measures the distance from the center of one through hole to the center of the other through hole, for a measurement object having at least a pair of through holes,
A shaft that can be inserted into the through-hole, a centering member that is fitted to the shaft and has at least three conical curved surfaces formed on the outer surface, and the centering member is an arbitrary one in the axial direction of the shaft. Measuring point setting means having fixing means fixed at a position;
The measurement point setting means is mounted on each of the pair of through holes, and the distance measurement means measures the distance between the center positions of the end surfaces of the shafts of both measurement point setting means. Distance measuring device. A pair of centering members are attached to the shaft so as to be fitted from both sides of the through-hole, at least one flat surface portion is formed on the outer surface of the shaft, and a set screw is attached to the centering member. 2. The inter-hole distance measuring device according to claim 1, wherein a tip of the set screw is fixed to the shaft by being brought into pressure contact with the flat surface portion. The inter-hole distance measuring device according to claim 1, wherein the distance measuring means is a measure that is detachably fixed to an end surface of the one shaft and can extend to an end surface of the other shaft.

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