Measuring device and control method

Abstract

Measuring device (1), in particular roundness measuring device (1), which includes a rotating table (20) on a base (10) and is configured to measure the roundness of an outer circumferential surface and an inner circumferential surface of a measuring object (W) placed on the rotating table (20) while the rotating table (20) is rotated, wherein measuring device (1) comprises: a detection device main body (32), a displacement device (40) configured to displace the main body of the detection device (32) relative to the base (10); a stylus (30) which has a base end rotatably held on the main body of the detection device (32) and is configured to change an angular position (θ) relative to the main body of the detection device (32); at least one contact element (50; 150) which is arranged in a position such that it can be contacted with the stylus (30) due to a displacement of the main body of the detection device (32) by the displacement device (40); and a drive control (60) configured to change the angular position (θ) of the stylus (30) between a position for measuring the outer circumferential area and a position for measuring the inner circumferential area by controlling the displacement device (40) such that the stylus (30) is selectively moved in one direction to come into contact with the contact element (50; 150) or in the opposite direction to come into contact with the contact element (50; 150) by displacing the main body of the detection device (32) by means of the displacement device (40).

Description

CROSS-REFERENCE TO RELATED REGISTRATIONS

[0001] The present invention claims priority from the Japanese patent application JP 2016 - 65 751 A, filed on September 24, 2014, the disclosure of which is explicitly included in its entirety by cross-reference here. BACKGROUND OF THE INVENTION 1. Field of the invention

[0002] The present invention relates to a measuring device, in particular a roundness measuring device, and a method for controlling or regulating the measuring device, in particular the roundness measuring device. In particular, the present invention relates to a measuring device capable of automatically changing the position angle of a stylus, and to a method for controlling or regulating the measuring device. 2. Description of the relevant technology

[0003] A roundness measuring device is a known example of a measuring device that measures the roundness of a test object. The roundness measuring device comprises a base, a rotating table on which a test object is placed and which is rotatably mounted on the base, a rotary drive mechanism that drives the rotary table, a column standing upright on the base, a sliding element arranged so that it is able to move up and down vertically along the column, a sliding arm arranged on the sliding element so that it is able to slide in a direction orthogonal to a vertical axis, and a sensing unit that outputs an electrical signal from the displacement of a stylus, which is attached to a front end of the sliding arm and touches the test object.

[0004] When measuring external / internal circumferential surfaces, a stylus in a conventional roundness measuring device was held at an angle relative to the main body of a sensing device, so that the main body of the sensing device did not interfere with the workpiece (see, for example, Japanese Patent Publication JP H05-133701A). When measuring an internal circumferential surface, particularly the internal circumferential surface of a small-diameter bore, a stylus or sensing device interferes with an edge of the bore if the stylus is angled. Therefore, when measuring the internal circumferential surface, the stylus was inserted into the bore of the workpiece after it had been vertically aligned.

[0005] However, the task of switching the stylus between an inclined and a vertical position was traditionally performed manually by an operator, and therefore the workflow could not be improved. For example, within a series of measurements on the workpiece, in a case involving measurements of both the outer circumferential surface (with the stylus inclined) and the inner circumferential surface of a small bore (with the stylus vertical), manual intervention was required to change the inclination mid-operation. Although a series of measurements is performed automatically, a process was therefore necessary where the automated workflow is paused mid-operation and the system waits for operator intervention, thus preventing full automation and work efficiency.Furthermore, the stylus can be connected to the motor, and its inclination can be changed, for example, by driving the motor. However, in such a case, the configuration becomes more complex, and the motor's heat generation must be taken into account. Thermal expansion due to the motor's heat can cause measurement errors. SUMMARY OF THE INVENTION

[0006] US 2011 / 0088273A1 discloses a force-measuring control device in which a position controller receives a difference between a detected rotation angle of a stylus and a target rotation angle. The excitation value of a motor is then determined to reduce the difference to zero. The drive current is limited to a threshold value so that the torque applied to the stylus remains constant.

[0007] US 5,848,477 A discloses a coordinate measuring machine in which drives for measuring slides of the device are controlled on circular paths to set the spatial orientation of a probe pin. The probe pin is attached to a passive pivot joint and has a probe ball that is placed in one of several centering holes of a body.

[0008] DE 28 04 398 A1 discloses a coordinate measuring machine comprising components movable by means of an electric motor drive for a three-dimensionally movable mounting of a measuring head relative to a stationary frame structure, and a probe arranged on the measuring head. The probe is pivotally mounted at the free end of an arm, which is articulated to the measuring head by means of a joint connection, relative to the measuring head. Furthermore, means are arranged on the joint connection that counteract a relative pivoting movement of the arm with respect to the measuring head, provided that the magnitude of any torque acting on the arm is below a given limit value.

[0009] US 2005 / 0256672A1 discloses a stylus alignment in which a portion of the stylus engages with a fixed portion and the stylus is moved on a spherical path around the engagement point. The engagement point is spaced from the stylus tip and prevents bending of the stylus during realignment.

[0010] In light of the foregoing, the present invention provides a measuring device with improved ease of use, which is in particular able to automatically change the angular position of a stylus using a simple configuration, as well as a method for controlling or regulating the measuring device.

[0011] This problem is solved according to the invention by the features of the independent claims. Specific embodiments of the invention are the subject of the dependent claims.

[0012] According to one aspect, a measuring device, in particular a roundness measuring device, is provided which includes a rotating table on a base and is configured to measure the roundness of an outer circumferential surface and an inner circumferential surface of a measuring object to be arranged on the rotating table while the rotating table is rotated, wherein the measuring device comprises: a sensing device main body; a displacement device configured to displace the sensing device main body relative to a base; a stylus whose base end is rotatably held on the sensing device main body and configured to change an angular position relative to the sensing device main body;at least one contact device arranged in a position such that it can be brought into contact with the stylus by means of a displacement of the sensing device main body by the displacement device; and a drive control configured to change an angular position of the stylus between a position for measuring the outer circumferential area and a position for measuring the inner circumferential area by controlling the displacement device such that the stylus is selectively moved in one direction to be brought into contact with the contact element (50; 150) or in the opposite direction to be brought into contact with the contact element (50; 150) by displacement of the sensing device main body by the displacement device.

[0013] According to a particular embodiment, a roundness measuring device is provided which includes a rotating table on a base and measures the roundness of a test object placed on the rotating table while the table is rotated. The roundness measuring device comprises a sensing device body, a displacement mechanism (displacement device), a stylus, a contact element (contact device), and a drive control. The displacement mechanism displaces the sensing device body relative to the base. One end of the stylus is rotatably mounted on the sensing device body and is capable of changing its angular position relative to the sensing device body by applying an external force. The contact element is arranged such that it is not capable of relative displacement relative to the base end and is able to be in contact with the stylus.The drive control system controls the drive of the sliding mechanism.

[0014] In the above-mentioned setup, the roundness measuring device measures the roundness of the object being measured while the rotary table is rotated. Specifically, the main body of the measuring device is moved by the displacement mechanism, and the roundness is measured by utilizing the fluctuation of a circumferential surface of the object during rotation. This is achieved by bringing the stylus into contact with the circumferential surface, which is a measurement section of the object. The smaller the fluctuation of the circumferential surface, the greater the roundness of the object. The measurement section of the object can be an outer circumferential surface (axis) or an inner circumferential surface (bore). When measuring roundness in a case where the outer circumferential surface of the object is a long vertical plane, the stylus must be inclined to prevent the main body of the measuring device from interfering with the object.When measuring roundness in a case where a small-diameter, axially oriented bore is formed in the center of the object being measured, the stylus must be vertical to prevent the main body of the measuring device and the stylus from interfering with an edge of the bore. Therefore, the angular position of the stylus is preferably adjusted depending on whether the measuring section of the object is the outer or inner circumferential surface. If the measuring section of the object is either the outer or inner circumferential surface, the angle of the stylus can be preset. However, the measuring section of the object can be either the outer or the inner circumferential surface.In such a case, the conventional method was to perform the measurement of the other circumferential surface at the time when the measurement of one circumferential surface was completed, after the angular position of the stylus had been changed by temporarily interrupting the measurement.

[0015] As described above, the (in particular roundness) measuring device includes the stylus, which is capable of changing its angular position relative to the main body of the measuring device using an external force, and the contact element, which is capable of making contact with the stylus. Therefore, the angular position of the stylus relative to the main body of the measuring device can be changed by bringing the stylus into contact with the contact element. In other words, the driving force of the displacement mechanism allows the stylus to be switched (in particular automatically) between the inclined state (first state) and the vertical state (second state). Therefore, with a simple configuration, the angular position of the stylus can be changed without interrupting the automatic process.Since the sliding mechanism is already present in the measuring device (especially the roundness measuring device), it is unnecessary to provide a separate mechanism solely for driving the stylus. Therefore, costs and weight can be reduced, and measuring accuracy can be maintained, as the influence of thermal expansion is avoided by not increasing the number of motors, which are a source of heat generation.

[0016] According to a particular embodiment, preferably at least one angular position sensor is provided which detects the angular position of the stylus. Consequently, the angular position of the stylus is detected by the angular position sensor. Therefore, the change or adjustment of the angle can be confirmed when the angular position of the stylus is changed. In other words, the change in the angular position of the stylus can be carried out precisely, and by continuing the movement using the displacement mechanism after the change is complete, excessive external force on the stylus can be prevented.

[0017] In particular, the contact element or contact device is designed in a protruding form with respect to an installation surface.

[0018] Since the contact element or contact device is formed in the aforementioned manner with respect to the installation surface, the stylus is consequently displaced so that it is located in front of the contact element and is caused to remain on this path in order to make contact with the contact element or contact device. Therefore, changing the angular position of the stylus can be easily accomplished. Furthermore, cutting is required if a recess is formed on a flat surface; however, attaching a separate element is sufficient if a protruding section is formed. Therefore, the contact element or contact device can be easily installed in the aforementioned manner while a suitable position is being investigated.

[0019] Furthermore, the contact element or contact device is preferably provided in a pluggable / removable manner. Since the contact element or contact device is provided in a pluggable / removable manner, consequently, even if the contact element or contact device is worn out or damaged by repeated contact with the stylus, only the contact element or contact device needs to be replaced, thus reducing maintenance costs.

[0020] Furthermore, the contact element or contact device is preferably configured for selective mounting at one of several positions. Consequently, the mounting position of the contact element / contact device can be chosen. In other words, the optimal mounting position of the contact element / contact device can be selected depending on the type and measuring surface of the object being measured. This reduces the displacement distance of the displacement mechanism for changing the angular position of the stylus, and allows the angular position of the stylus to be changed more quickly.

[0021] Furthermore, the contact element / contact device is preferably coated with a damping or spring-like material. Because the contact element is coated with a damping / spring-like material, damage to the stylus at the time of contact is minimal. This extends the stylus replacement cycle.

[0022] According to a further aspect of the invention, a method for controlling or regulating a measuring device, in particular a roundness measuring device, is provided, which includes a rotating table on a base and measures the roundness of an outer circumferential surface and an inner circumferential surface of a measuring object to be arranged on the rotating table while the rotating table is rotated, wherein the method uses a measuring device and the measuring device comprises a sensing device main body; a displacement device configured to displace the sensing device main body relative to a base; a stylus whose base end is rotatably held on the sensing device main body and configured to change an angular position relative to the sensing device main body;a contact device arranged in a position such that it can be brought into contact with the stylus by means of a displacement of the sensing device main body by the displacement device; and a drive control configured to control or regulate the driving of the displacement device, wherein the method comprises: displacing the sensing device main body by means of the displacement device selectively in one direction to be brought into contact with the contact element or in the opposite direction to be brought into contact with the contact element; bringing the stylus into contact with the contact device;and rotating the stylus to a specific angle relative to the main body of the sensing device by moving the main body of the sensing device in order to change the angular position of the stylus between a position for measuring the outer circumferential area and a position for measuring the inner circumferential area.

[0023] According to a preferred embodiment, a method for controlling the roundness measuring device of the present invention is provided, which measures the roundness of the measuring object arranged on the rotary table while the rotary table is rotated, the rotary table being arranged at the base. The method uses the roundness measuring device, which includes the sensing device main body, the displacement mechanism, the stylus, the contact element, and the drive control. The displacement mechanism displaces the sensing device main body relative to the base. The base end of the stylus is rotatably held on the sensing device main body and is able to change its angular position relative to the sensing device main body by applying an external force.The contact element is positioned so that the stylus can be brought into contact by moving the main body of the sensing device using the movement mechanism. The drive control directs the movement of the mechanism. The method includes moving the stylus so that it is close to the contact element; bringing the stylus into contact with the contact element; and rotating the stylus to a (predetermined or predeterminable) angle relative to the main body of the sensing device.

[0024] In the above method, switching the measuring surface from the outer circumferential surface to the inner circumferential surface (or vice versa), particularly while measuring roundness, is carried out as follows. First, the stylus is positioned close to the contact element by the displacement mechanism, away from the object being measured. Then, the stylus is rotated to the specified (predefined or predefinable) angle relative to the main body of the sensing device by bringing it into contact with the contact element. Finally, the stylus is moved back towards the object being measured. This process brings the stylus closer to the contact element, and its angular position relative to the main body of the sensing device can be changed. Therefore, the angular position of the stylus relative to the main body of the sensing device can be changed during a series of measurements without interrupting the automatic measurement process.Furthermore, in the method for controlling the (in particular roundness) measurement according to the above, the method, in particular at the time of the roundness measurement, can control the displacement of the stylus from the object being measured, such that it is close to the contact element, the rotation of the stylus to a certain (predetermined or predeterminable) angle relative to the main body of the detection device, by bringing the stylus into contact with the contact element and moving the rotated stylus back towards the object being measured.

[0025] According to a particular embodiment, the method further includes detecting the angular position of the stylus.

[0026] Furthermore, the shifting device is controlled in particular based on the detected angular position.

[0027] Furthermore, the method includes in particular the attachable and removable mounting of the contact device and / or the optional fastening of the contact device at one of several positions. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention is further described in the following detailed description with reference to the aforementioned multiple drawings, using non-limiting examples of exemplary embodiments of the present invention, where the same reference numerals denote similar parts across the different views of the drawings. It should be noted that, even if embodiments are described separately, individual features thereof can be combined to form further embodiments. Fig. Figure 1 is a perspective view showing a roundness measuring device according to an embodiment of the present invention; Fig. Figure 2 is a side view of the roundness measuring device; Fig. Figure 3 shows a main body of the detection device and a stylus of the roundness measuring device; Fig. Figure 4 is a perspective view showing a second sliding drive mechanism of the roundness measuring device; Fig. Figure 5 is a side view showing operations of a swivel drive mechanism of the roundness measuring device; Fig. Figure 6 is a perspective view showing a measuring range of the roundness measuring device; Fig. Figure 7 is a block diagram showing a control mechanism of the roundness measuring device and peripheral mechanisms; Fig. 8A and Fig. 8B are cross-sectional views of measurement states of the roundness measuring device; Fig. 9A and Fig. 9B are explanatory illustrations of a procedure for changing the angular positions of the stylus; and Fig. Figure 10 is a side view of the roundness measuring device, which contains a modified example of a contact element. DETAILED DESCRIPTION OF THE INVENTION

[0029] The details shown here are exemplary and serve only to illustrate the embodiments of the present invention. They are presented as the most useful and readily understandable description of the fundamentals and conceptual aspects of the present invention. In this respect, no attempt is made to describe structural details of the present invention in more detail than is necessary for a basic understanding of the invention, since the description, with reference to the drawings, clarifies for those skilled in the art how the forms of the present invention are to be implemented in practice. Explanation of the roundness measuring device

[0030] As in the Fig. 1 and Fig. As shown in Figure 2, a roundness measuring device 1 of the present embodiment comprises a base 10, a rotary table 20, a sensing device 30, a sensing device drive mechanism 40, a contact element 50, and a control mechanism 60. The rotary table 20 is centered on a vertical axis L on one side of the base 10 (left side in Figure 2). Fig. 2) rotatably arranged, and a measuring object W is placed or can be placed on an arrangement surface (in particular an upper surface) of the rotary table 20. The detection device drive mechanism 40 drives the detection device 30 in a direction parallel to the vertical axis L and in a direction at an angle other than 0° or 180°, preferably perpendicular to the vertical axis L and approaching / moving away from the rotary table 20.

[0031] The rotary table 20 is configured to be rotatably driven by a rotary drive mechanism 23 and includes a cylindrical main body 21 rotatably mounted on the base 10 and a (particularly essentially disc-shaped) mounting plate 22, on the mounting surface (particularly an upper surface) of which the object W is arranged or is to be arranged and which is attached to the main body 21 (particularly to an upper part thereof). The rotary drive mechanism 23 includes a motor that rotatably drives the rotary table 20 and a mechanism that transmits rotation from the motor to the rotary table 20 via a speed reducer.

[0032] As seen in an enlarged view in Fig. As shown in Figure 3, the sensing device 30 comprises a stylus 31 which touches the object W, a sensing device main body (as a special sensing device main body) 32 which rotatably and attachably / removably holds the stylus 31, and an angular position detector switch 33 as a standard position sensing unit. A standard axis C is an imaginary line that coincides with the axis of the sensing device main body 32 and is used as a reference standard for expressing an angular position of the stylus 31. Hereinafter, an angle between the stylus 31 and the standard axis C is referred to as the angular position θ.

[0033] In particular, when an external force is applied, the stylus 31 pivots or rotates within a certain (predetermined or predeterminable) rotation range relative to the main body of the detection device 32 in a direction containing an XZ plane.

[0034] The stylus 31 does not rotate in any other direction. In the present embodiment, the defined (predetermined or predeterminable) rotation range is, in particular, a range in which the angular position θ lies, for example, between 0° and approximately 15°. In the present embodiment, the angular position θ = 15° is an initial position of the stylus 31. In other words, the angular position θ of the stylus 31 is, in particular, 15° at the beginning and at the end of the measurement. The angular position detector switch 33 outputs a detection signal, which expresses the angular position, to the control mechanism 60 when the angular position θ of the stylus 31 relative to the standard axis C is a specific angle, such as approximately 0° and approximately 15°.

[0035] Rotating or pivoting the stylus 31 requires, in particular, an external force equal to or greater than a certain (predetermined or predeterminable) value. Specifically, the stylus 31 does not simply rotate due to vibration from the rotary table 20 and the sensing drive mechanism 40, which moves the sensing device 30. A method for pivoting or rotating the stylus 31 is described below.

[0036] The detection device drive mechanism 40 (such as, in particular, a sliding device) comprises a column 41, a lifting drive mechanism, a first sliding drive mechanism 45, a second sliding drive mechanism 46, and a pivoting drive mechanism 47. The column 41 is erected upright on the other or substantially opposite side of the base 10 (right side in Fig. 2) arranged. The lifting drive mechanism 43 drives a lifting slide element 42 relative to the column 41 essentially in an upward / downward direction or towards / away from the base 10 (direction of the Z-axis). The first sliding drive mechanism 45 drives a sliding arm 44 relative to the lifting slide element 42 in a direction at an angle other than 0° or 180°, preferably essentially orthogonal to the vertical axis L, or in a direction of approach / removal relative to the rotary table 20 (direction of the X-axis). The second sliding drive mechanism 46 is arranged on the sliding arm 44 (in particular at a front end thereof) and displaces the detection device 30 in a direction at an angle other than 0° or 180°, preferably orthogonally with respect to a sliding axis (X-axis) of the sliding arm 44. The pivoting drive mechanism 47 rotates the second sliding drive mechanism 46, which is centered on the sliding axis of the sliding arm 44.

[0037] The lifting drive mechanism 43 can be configured in any way, as long as the lifting slide element 42 is able to move in the upward / downward direction or towards / away from the base 10 (direction of the Z-axis). Although not shown in the drawings, for example, a feed or displacement mechanism can be used which includes a ball screw shaft arranged upright on the column 41 in the upward / downward direction, a motor for rotating the ball screw shaft, and a nut element that is screwed onto or engaged with the ball screw shaft and connected to the lifting slide element 42.The first sliding drive mechanism 45 can also be configured in any way, as long as the sliding arm is able to move in a direction at an angle other than 0° or 180°, preferably substantially orthogonal to the vertical axis L and / or in a direction of approach / retraction with respect to the rotary table 20. Although not shown in the drawings, a configuration can be used, for example, in which a rail is formed along a longitudinal direction of the sliding arm 44 and which provides a pinion engaging with the rail and a motor that rotates the pinion within the sliding element 42.

[0038] As in Fig. As shown in Figure 4, the second sliding drive mechanism 46 has a feed or displacement mechanism comprising a housing element 46A, which is attached to the sliding arm 44 (particularly at its front end) at an angle other than 0° or 180°, preferably substantially at a right angle; a ball screw shaft 46B, which is rotatably arranged in the housing element 46A; a motor 46C, which rotates the ball screw shaft 46B; a nut element 46D, which is screwed onto or engages with the ball screw shaft 46B; and a sensing device holder 46E, which contains the nut element 46D and holds the sensing device 30. Furthermore, the second sliding drive mechanism 46 is not limited to the configuration of Fig. 4 limited.

[0039] The pivoting drive mechanism 47 is configured, for example, with a pivoting shaft (not shown in the figures) rotatably arranged in the sliding arm 44 and connected to a section (in particular a front end) on the housing element 46A of the second sliding drive mechanism 46, and a motor 47B, which is arranged at a base end of the pivoting shaft and pivotally drives the pivoting shaft. From a Fig. Viewed in the X-direction shown in Figure 5, in the present embodiment the position of the detection device 30 in which the stylus 31 runs essentially in the upward / downward direction (Z-axis) is set to 0°, in particular, and the position of the detection device 30 is configured so that it can be changed within a range of approximately -90° to approximately +90°.

[0040] The contact element 50 is, in particular, essentially hook-shaped and comprises a horizontal section 50A (first section) extending horizontally and a vertical section 50B (second section) extending at an angle other than 0° or 180°, preferably substantially perpendicular or vertically from an edge of the horizontal section 50A. The contact element 50 is used to rotate the stylus 31 by coming into contact with it. The contact element 50 is, in particular, made of a rigid material (such as iron). Furthermore, a surface of the contact element 50 can be coated with a (particularly thin) damping or compliant material (such as rubber). The damping material can improve the durability of the stylus 31 and the contact element 50. As described in Fig. As shown in Figure 2, a bore 41A is formed at an upper end and a bore 41B at a lower end of a surface of the column 41 facing the rotary table 20. Round annular projections 41C and 41D are each attached to a position corresponding to the bores 41A and 41B, respectively, with each projection having a screw bore extending radially through it. To ensure that the vertical section 50B is oriented substantially upwards, a front end of the horizontal section 50A is inserted through the bore 41A in the present invention, and the contact element 50 is fastened to the projection 41C by a threaded screw.

[0041] As shown by dashed lines in Fig. As shown in Figure 2, the contact element 50 can also be inserted through the bore 41B and secured such that the vertical section 41B points substantially downwards. The front end of the horizontal section 50A and the bores 41A and 41B can be machined by wedge or notch machining such that the vertical section 50B points in a specific (predetermined or predeterminable) direction (for example, approximately 0°, approximately 90°, approximately 180°, and approximately 270°). The contact element 50 is preferably located outside a measuring range A (indicated by dashed lines in Figure 2). Fig. 6 (indicated limit area) is arranged, which is defined by a displacement range of the rotary table 20 and the detection device drive mechanism 40. The previously described second sliding drive mechanism 46 and the swivel drive mechanism 47 are configured such that they are able to move the stylus 31 to the contact element 50 and establish contact.

[0042] The displacement range of the stylus 31 differs depending on the type of object W being measured, and the displacement range of the stylus 31 can also be defined by a measurement program for the same object W. In particular, even if the contact element 50 lies within the measuring range A, the contact element 50 does not immediately become an obstacle to the measurement. Therefore, the contact element can be located within the measuring range A, provided it does not pose an obstacle to the measurement. Description of the control system

[0043] As in Fig. As shown in Figure 7, a main control system comprises the control mechanism 60, an input device 61, a display device 62, and a storage device 63. The storage device 63 is equipped with a program memory 63A, a data memory 63B, and the like. The program memory 63A stores, or is configured to store, a measurement program, an angle position change program, and the like. The data memory 63B stores, or is configured to store, measurement data recorded during the measurement.

[0044] In addition to the input device 61, the display device 63, and the storage device 63, the control mechanism 60 is also connected, for example, to the rotary drive mechanism 23, the lifting drive mechanism 43, the first sliding drive mechanism 45, the second sliding drive mechanism 46, the pivot drive mechanism 47, the sensing device 30, and / or the angular position sensing switch 33. Based on the measurement program and the angular position change program, which are stored in particular in the program memory 63A, the control mechanism 60 controls the drive of each mechanism as a drive controller and includes, in particular, receiving and processing a sensing signal from the sensing device 30. Specifically, when a measurement command is issued, the measurement of the roundness and the like of the object W is performed, while the movement of the rotary drive mechanism 23 and the sensing drive mechanism 40 is controlled. Description of the measuring movement

[0045] Measurement positions of one or more different objects W, measurement processes, analysis elements, and the like are stored in advance in the storage device 63. When the type of object W is determined (e.g., detected and / or specified by input from the input device 61), the type of object W is sent to the program memory 63A, and the control unit (e.g., the program memory 63A) calls up the measurement program corresponding to the object W. When the measurement command has been issued from the measurement program to the control mechanism 60, the rotary table 20 is driven to rotate, and the acquisition device drive mechanism 40 is driven.In particular, when the lifting drive mechanism 43 and the first sliding drive mechanism 45 (and the swivel drive mechanism 47, if necessary) are activated, the detection device 30 moves in a direction towards the object W being measured, and the stylus 31 of the detection device 30 touches the rotating object W being measured.

[0046] The stylus 31 moves, and this movement is transmitted to the main body 32 of the sensing device. The main body 32 of the sensing device then outputs a signal (in particular, continuous or intermittent) expressing the movement of the stylus 31 to the control mechanism 60. After the data storage device 63B has stored the input signals as data, the control mechanism 60 calculates the roundness based on the stored data and outputs the result, e.g., displays the result on the display device 62. The roundness measurement of the object W is performed, in particular, at various sections while the sensing device 30 is moved in a Z-direction by driving the second sliding drive mechanism 46.

[0047] In this embodiment, the measuring surface of the object W can be an outer circumferential surface (axis) and an inner circumferential surface (bore). When measuring the roundness of the object W, if the outer circumferential surface, as in Fig. As shown in Figure 8A, if a long vertical plane is involved, the angular position θ of the stylus 31 is maintained at its initial position (e.g., approximately 15°) to prevent the main body of the sensing device 32 from interfering with the object W being measured. However, if the roundness of a small-diameter bore H, running axially and located in the center of the object W, is being measured, the angular position change program is executed. As shown in Figure 8A, the angular position change program is executed. Fig. As shown in Figure 8B, the angular position θ of the stylus 31 is changed (e.g. to approximately 0°) in order to prevent, in particular, the stylus 1 and the sensing device main body 32 from interfering with an edge of the bore H. Description of the procedure for changing the angular position θ of the stylus 31

[0048] A method for changing the angular position θ of the stylus 31 is described with reference to the Fig. 9A and Fig. 9B described. The following is an example case in which the roundness measurement of the object W is performed on the outer circumferential surface and the inner circumferential surface in that order. After completion of the roundness measurement of the outer circumferential surface of the object W, the control unit (e.g., the program memory 63A) calls up the angular position change program. By driving the first sliding drive mechanism 45 with the angular position change program, the stylus 31 is separated from the object W, for example, in the X+ direction. Then, by driving the swivel drive mechanism 47, the position of the detection device 30 is tilted, for example, by +90° (see Fig. 5) If the position of the detection device 30 is tilted by, for example, +90°, the detection device 30 can be moved in a Y direction by driving the second sliding drive mechanism 46. Thus, the detection device 30 is able to move in the X direction by driving the first sliding drive mechanism 45, in the Y direction by driving the second sliding drive mechanism 46, and in the Z direction by driving the lifting drive mechanism 43.

[0049] By driving the lifting drive mechanism 43, the first sliding drive mechanism 45 and the second sliding drive mechanism 46, the stylus 31 is then moved, in particular, to a position between the column 41 and the vertical section 50B of the contact element 50 (one in Fig. (position shown in 9A). When the detection device 30 is moved from this position in the X-direction (shown in 9A) by driving the first sliding drive mechanism 45, Fig. 9A (direction shown with an arrow) is moved, the stylus 31 then comes into contact with the contact element 50 and rotates. When the angular position θ of the stylus 31 relative to the main body of the sensing device 32 becomes, in particular, the minimum 0°, the first sliding drive mechanism 45 stops upon a detection signal expressing this state, which is output by the angle position detection switch 33 to the control mechanism 60. Then the sensing device 30 is moved, in particular, to a position before the inclination of +90° (0° position in Fig. 5) reset, for example by activating each drive mechanism, and the stylus 31 is reset as in Fig. 8B shown, inserted through the bore H of the object being measured, whereupon the roundness measurement of the inner circumferential surface of the object being measured W begins.

[0050] After completion of all roundness measurements of the outer circumferential surface and the inner circumferential surface, the stylus 31 is driven by each drive mechanism, in particular towards the X-side of the contact element 50 (in Fig. (position shown in 9B). If the stylus 31 then moves from this position by driving the first sliding drive mechanism 45, particularly in the X+ direction (which is shown in Fig. When the probe (9B, indicated by an arrow) moves in the direction indicated by an arrow, the stylus 31 comes into contact with the contact element 50 and rotates. When the angular position θ of the stylus relative to the main body of the sensing device 32 reaches its maximum of 15°, the first sliding drive mechanism 45 stops upon receiving a detection signal indicating this state, which is sent from the angle position detection switch 33 to the control mechanism 60. Then, each drive mechanism is actuated and returned to its initial position, completing a series of roundness measurements.

[0051] As mentioned above, the stylus 31, which is capable of changing its angular position θ relative to the main body of the sensing device 32, particularly by utilizing an external force, e.g., from the sliding mechanism (also referred to as a sliding device) or an actuator (particularly separate from the stylus 31), and the contact element 50, which is capable of coming into contact with the stylus 31, are provided in the present embodiment. Therefore, the angular position θ of the stylus 31 relative to the main body of the sensing device 32 can be changed by causing the stylus 31 to come into contact with the contact element 50. In other words, the angular position θ of the stylus 31 can be changed between different angles (e.g., between approximately 15° and approximately 0°) by using the driving force of the sliding mechanism (particularly automatically).Therefore, the angular position θ of the stylus 31 can be changed during a series of measurement operations without interrupting the automatic process. Furthermore, the displacement mechanism is a mechanism already present in the roundness measuring device 1, eliminating the need for a separate mechanism solely for driving the stylus 31. Consequently, costs and weight can be reduced, and measurement accuracy can be maintained by avoiding the effects of thermal expansion, as the number of motors, which are a source of heat generation, is not increased.

[0052] Since the angular position θ of the stylus 31 is maintained in particular by the angular position detection switch 33, the changing of the angular position θ of the stylus 31 can be carried out safely, and excessive external force when contacting the stylus 31 can be avoided.

[0053] Since the contact element 50 is designed in a projecting form relative to the column 41, the stylus 31 is displaced so that it lies in front of the contact element 50 and is caused, or can be caused, to remain on the path to the contact element 50. Therefore, changing the angular position θ of the stylus 31 can be easily accomplished.

[0054] The contact element 50 is attached separately to the column 41 (e.g., screwed in place) and can be replaced as a single unit. Even if the contact element 50 is damaged by repeated contact with the stylus 31, only the contact element 50 needs to be replaced, thus reducing maintenance costs. Furthermore, the contact element 50 is coated with a damping or compliant material, minimizing damage to the stylus 31 upon contact. Consequently, the replacement cycle for the stylus 31 can be extended. Description of contact element 150 in the modified form

[0055] Fig. Figure 10 is a side view of the roundness measuring device 1, which is equipped with a modified form of a contact element 150. The configuration in Fig. The embodiment 10 is similar to or exactly the same as the embodiment described above, with the exception of the contact element 150. Therefore, identical reference numerals are used for structures similar to those of the embodiment described above, except for the contact element 150, and a description of these structures is omitted here. The contact element 150 is a rod-like element that extends vertically and is attached to a projection 10B by a threaded screw. A lower end of the contact element 150 is inserted through a bore A10 formed in the base 10, extending in the upward / downward direction or towards / away from the base 10 (Z-axis direction). Furthermore, the surface of the contact element 150, similar to the contact element 50 of the embodiment described above, can be coated with a thin damping or compliant material (such as rubber).Changing the angular position θ of the stylus 31 using the contact element 150 can also be carried out in a manner fundamentally similar to that of the embodiment described above. According to the roundness measuring device 1 of the modified embodiment, the contact element 150 is attached to the surface of the base 10; therefore, changing the angular position θ of the stylus 31 can be carried out without significantly moving the sliding element 42 upwards, even if the height of the object W being measured is small.

[0056] If the contact element 150 is arranged in a position that overlaps the sliding arm 44 in the Z-direction, the angular position θ of the stylus 31 can be changed, particularly in a state where the position of the sensing device 30 is 0°, without driving the pivoting drive mechanism 47. To bring the downward-facing stylus 31 into precise contact with the contact element 150, the contact element 150 can preferably be designed in a shape having a lateral width or extent (Y-direction), such as a block shape, a U-shape, or an L-shape.

[0057] The present invention is not limited to the aforementioned embodiment(s) and the modified example and includes modifications and improvements of a scope capable of achieving the advantages of the present invention. For example, although in the aforementioned embodiment the stylus 31 contacts the substantially horizontally oriented (+90° of the position that is in Fig. 5 (indicated by a dashed line) Detection device 30 the vertical section 50B of the contact element 50, but the stylus 31 can be in the substantially vertically oriented (position which is in Fig. (5, indicated by a solid line) the detection device 30 comes into contact with a contact element by arranging the contact element so that it runs horizontally (Y-direction). In such a case, the contact element 50 is arranged in a position lower than the sliding element 42.

[0058] In the above embodiment, the contact element 50 is rod-shaped, but as long as precise contact can be established with this shape, any other shape, such as a spherical or block shape, can be used. Furthermore, the contact element 50 need not be in the above shape and can, for example, be provided with a notch and rotated into position by engaging the stylus 31 in the notch. A plurality of notches can be provided.

[0059] The contact element 50 can be arranged such that it makes contact with the stylus 31, for example, outside the base 10. However, a position that does not interfere with the measurement is preferable. In the embodiment described above, a single contact element 50 is optionally mounted on either bore 41A or bore 41B formed in the column 41, but the contact element can be mounted on both bores 41A and 41B. Furthermore, the contact element 50 can be permanently attached to bores 41A and 41B.

[0060] In the embodiment described above, the stylus 31 is configured to rotate only in one direction along the XY plane; however, the stylus 31 can also be configured to rotate in another direction or in all directions. Even in a case where the stylus 31 rotates in all directions, the direction of rotation remains constant as long as the contact direction is constant.

[0061] In the aforementioned embodiment(s), the angle position detection switch 33, which is used as the angle position detector, is of a type that outputs the detection signal when the angle position θ is equal to 0° and equal to 15°; however, the angle position detector can also be of a type that outputs a (substantially continuous) detection signal expressing the angle position θ by using a different representative value that represents the angle position θ, such as a variable resistor where the resistance value varies depending on the angle position θ. By counting the extent or magnitude of the displacement of the sliding arm 44 by the first sliding drive mechanism 45 when changing the angle position θ, a change in the angle position θ on a forward basis can be calculated or determined from the counted value.Additionally or alternatively, by taking an image of the stylus 31 with a camera when the angular position θ is changed, the angular position θ of the stylus 31 can be calculated or determined from the image data. In other words, the detection of the angular position θ of the stylus 31 can be carried out remotely using light or a signal.

[0062] In the aforementioned embodiment, a case was shown in which the roundness of the object W was measured in the sequence of outer circumferential surface and inner circumferential surface. However, the present invention is not limited to this, and the roundness can be measured in the sequence of inner circumferential surface and outer circumferential surface. Furthermore, the present invention can be applied not only to cases in which the roundness of the outer or inner circumferential surface is measured (particularly in a substantially continuous manner), but also to any case in which the angular position of the stylus 31 must be changed for a measurement other than a roundness measurement. Moreover, when switching the device on or off, the stylus 31 can be arranged, in particular, in a specific (predetermined or predeterminable) angular position (initial position) by applying the invention as required.Furthermore, in the aforementioned embodiment, the angular position θ of the stylus 31 to be used during the measurement was equal to 0° and equal to 15°, however, three or more angular positions θ can be used for the measurement. Industrial applicability of the invention

[0063] The present invention can be used in a roundness measuring device which measures the roundness of both the outer and inner circumferential surfaces of a measuring object in one measurement.

[0064] A roundness measuring device is disclosed, comprising a rotating table on a base and measuring the roundness of a measuring object arranged on the rotating table while the rotating table is rotated. The device includes a sensing body, a sensing device drive mechanism, a stylus, a contact element, and a control device. The sensing device drive mechanism displaces the sensing device body relative to the base. The stylus has a base end that is rotatably mounted on the sensing device body and can change its angular position relative to the sensing device body by applying an external force. The contact element is positioned so that the stylus makes contact due to the displacement of the sensing device body by the sensing device drive mechanism.The control device controls the drive of the detection device drive mechanism. It should be noted that the preceding examples serve only for illustrative purposes and are in no way to be considered limiting to the present invention. Although the present invention has been described with reference to exemplary embodiments, it should be emphasized that the terms used herein are descriptive and illustrative and are by no means limiting. Modifications may be made within the scope of the appended claims, as specified herein and as amended, without altering the scope and concept of the present invention in any aspect.Although the present invention has been described here with reference to certain structures, materials and embodiments, the present invention is not intended to be limited to the features disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses as they fall within the scope of the attached claims.

[0065] The present invention is not limited to the embodiments described above, and various variations and modifications may be possible without deviating from the scope of the present invention.

Claims

Measuring device (1), in particular a roundness measuring device (1), which includes a rotating table (20) on a base (10) and is configured to measure the roundness of an outer circumferential surface and an inner circumferential surface of a measuring object (W) placed on the rotating table (20) while the rotating table (20) is rotated, wherein the measuring device (1) comprises: a sensing device main body (32), a displacement device (40) configured to displace the sensing device main body (32) relative to the base (10); a stylus (30) having a base end rotatably held on the sensing device main body (32) and configured to change an angular position (θ) relative to the sensing device main body (32); at least one contact element (50;150), which is arranged in a position such that it can be contacted with the stylus (30) due to a displacement of the main body of the sensing device (32) by the displacement device (40); and a drive control (60) configured to change an angular position (θ) of the stylus (30) between a position for measuring the outer circumferential area and a position for measuring the inner circumferential area by controlling the displacement device (40) such that the stylus (30) is selectively moved in one direction to be brought into contact with the contact element (50; 150) or in the opposite direction to be brought into contact with the contact element (50; 150) by displacing the main body of the sensing device (32) by means of the displacement device (40). Measuring device (1) according to claim 1, further comprising at least one angular position detector (33) which is configured to detect the angular position (θ) of the stylus (30). Measuring device (1) according to one of the preceding claims, wherein the contact element (50; 150) has a projecting shape relative to an installation surface. Measuring device (1) according to one of the preceding claims, wherein the contact element (50; 150) is provided in a removable and pluggable manner. Measuring device (1) according to one of the preceding claims, wherein the contact element (50; 150) can be selectively mounted at one of several positions. Measuring device (1) according to one of the preceding claims, wherein the contact element (50; 150) is coated with a damping material. Method for controlling a measuring device (1), in particular a roundness measuring device (1), which includes a rotary table (20) on a base (10) and measures the roundness of an outer circumferential surface and an inner circumferential surface of a measuring object (W) placed on the rotary table (20) while the rotary table (20) is rotated, wherein the method uses a measuring device (1) wherein the measuring device (1) comprises a sensing device main body (32); a displacement device (40) configured to displace the sensing device main body (32) relative to the base (10); a stylus (30) having a base end rotatably held on the sensing device main body (32) and configured to change an angular position (θ) relative to the sensing device main body (32); a contact element (50;150), which is arranged in a position such that it can be contacted with the stylus (30) by means of a displacement of the detection device main body (32) by the displacement device (40); and includes a drive control (60) configured to control the drive of the displacement device (40), the method comprising: displacement of the detection device main body (32) by means of the displacement device (40) selectively in one direction to be brought into contact with the contact element (50; 150) or in the opposite direction to be brought into contact with the contact element (50; 150); bringing the stylus (30) into contact with the contact element (50; 150);and rotating the stylus (30) to a specific angle (θ) relative to the main body of the sensing device (32) by moving the main body of the sensing device (32) in order to change an angular position (θ) of the stylus (30) between a position for measuring the outer circumferential area and a position for measuring the inner circumferential area. Method according to claim 7, further comprising detecting the angular position (θ) of the stylus (30). Method according to claim 8, wherein the displacement device (40) is controlled starting from the detected angular position (θ). Method according to claim 7, 8 or 9, further comprising the removable and attachable provision of the contact element (50; 150) and / or the optional mounting of the contact element (50; 150) at one of several positions.

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