JP2019164000A - Surface shape measuring device - Google Patents

Abstract

To provide a surface shape measuring device capable of reducing a weight load to slide and guide a moving body moved by a linear body and reducing friction resistance.SOLUTION: A surface shape measuring device 10 including a linear motor 20 for relatively moving an object to be measured and a detector 16 includes: a first guide mechanism for sliding and guiding a moving body moved by thrust of the linear motor 20 in a first direction in parallel with a linear direction of the linear guide; a second guide mechanism that is disposed in a lower part in a gravity direction than the first guide mechanism and the moving body, and supports the moving body and guides the moving body in the first direction in parallel with a linear direction of the linear motor 20; and urging means that is disposed between the second guide mechanism and the moving body and gives force for operating on the moving body in a direction opposite to the gravity direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a surface shape measuring apparatus for measuring a surface shape such as a surface roughness and a contour shape of an object to be measured, and more particularly to a surface shape measuring apparatus using a linear motor.

  Many surface shape measuring devices represented by surface roughness measuring devices and contour shape measuring devices move the stylus and the object to be measured relative to each other while the stylus (probe) is in contact with the surface of the object to be measured. By detecting the displacement of the needle, the surface shape of the object to be measured is measured (see Patent Document 1).

  In the case of a surface shape measuring device, the relative movement between the stylus and the object to be measured is generally a linear motion along the measurement axis, and a linear motor is used as a drive mechanism for moving the stylus and the object to be measured relative to each other. A configuration using this is also known (see Patent Document 2).

JP 2006-300823 A JP 2004-125699 A

  The surface shape measuring device using a linear motor has the following problems [1] to [7].

  [1] Unlike the drive method using a rotary motor, in the linear motor drive method, the force cannot be amplified by a speed reducer or the like, so the thrust of the linear motor is approximately proportional to the magnitude. That is, in order to obtain a large driving force, a large linear motor must be employed.

  [2] When a linear guide, which is a low-friction guide mechanism, is used for guiding the slider of the surface shape measuring apparatus, small undulation (vibration) caused by the movement of the ball becomes a problem. For this reason, in order to realize a highly accurate measurement, it is necessary to use a sliding method for guiding the slider.

  [3] Further, when the linear guide is used for guiding the slider, a straightness higher than the base to which the linear guide is attached cannot be expected.

  [4] When the sliding method is used for guiding the slider, the weight of the moving body (slider portion) that moves integrally with the slider becomes the frictional resistance in the guidance.

  [5] When the slider part is heavy, it is necessary to use a high-thrust linear motor to compensate for frictional resistance.

  [6] Further, in the case of a workpiece movement type surface shape measuring device, the weight of the slider (part under test) is added to the slider, so the weight of the slider becomes variable. In that case, in order to ensure the range of the workpiece weight placed on the workpiece holding table, it is necessary to ensure an excessive thrust in the linear motor, which increases the size of the apparatus and increases the power consumption.

  [7] In the surface shape measuring apparatus, in order to obtain high straightness, the guide base used for the sliding guide is required not to be deformed from the viewpoint of correction. In particular, a highly rigid guide base is required so as not to be affected by deflection, such as when the slider portion is heavy or when the weight of the workpiece changes.

  This invention is made | formed in view of such a situation, and it aims at providing the surface shape measuring apparatus which can solve at least 1 subject among several subject mentioned above.

  It is an object of the present invention to provide a surface shape measuring apparatus that can reduce the weight load acting on the sliding contact surface of the sliding guide and reduce the frictional resistance.

  Another object of the present invention is to reduce the weight load on the guide base arranged along the linear motor linear movement direction, to suppress the deflection of the guide base, and for the guide having a relatively small rigidity. It includes providing a surface shape measuring device capable of realizing high straightness accuracy even if it is a base.

  Another object of the present disclosure is to actively adjust the magnitude of the force acting in the direction to cancel the weight load according to the weight of the object to be measured, so that it is not necessary to secure excess thrust of the linear motor And providing a surface shape measuring device capable of avoiding excessive specification of the linear motor.

  In order to achieve the above object, the following invention is provided.

  A surface shape measuring apparatus according to a first aspect of the present invention includes a detector that outputs a signal corresponding to the shape of the surface of the object to be measured, a linear motor that relatively moves the object to be measured and the detector, and a linear motor A first guide mechanism that slides and guides a moving body that moves by thrust in a first direction parallel to the linear motion direction of the linear motor, and is disposed below the first guide mechanism and the moving body in the gravitational direction. A second guide mechanism that supports and guides the moving body in a first direction parallel to the linear motor linear movement direction, and is disposed between the second guide mechanism and the moving body, and acts on the moving body in a direction opposite to the gravitational direction. Biasing means for providing a force to perform.

  According to the first aspect, a force (that is, an upward force) opposite to the gravitational direction is applied to the moving body that is slidably guided by the first guide mechanism by the urging means, and the moving body is pushed up by this force. As a result, the load (weight load) on the first guide mechanism due to the weight of the moving body is reduced. The weight of the moving body is supported by the second guide mechanism via the biasing means. According to the first aspect, it is possible to reduce the frictional resistance of the first guide mechanism. Moreover, according to the 1st aspect, the bending of a 1st guide mechanism can be suppressed. Thereby, high straightness accuracy can be realized.

  The surface shape measuring apparatus according to the second aspect of the present invention is the surface shape measuring apparatus according to the first aspect, wherein the first guide mechanism is slidable on the guide base and the guide base arranged in parallel with the linear motion direction of the linear motor. And a supported slider.

  In the surface shape measuring apparatus according to the third aspect of the present invention, in the first aspect or the second aspect, the second guide mechanism is a linear guide.

  The surface shape measuring apparatus according to the fourth aspect of the present invention is the surface shape measuring apparatus according to any one of the first aspect to the third aspect, wherein the urging means applies a force that cancels the weight load of the moving body to the first guide mechanism to the moving body. Give.

  By applying a reverse force of the magnitude that the urging means balances with the weight of the moving body, the weight load acting on the first guide mechanism can be canceled.

  The surface shape measuring apparatus according to the fifth aspect of the present invention is configured such that, in any one of the first to fourth aspects, the biasing means includes an elastic member that is elastically deformed in the direction of gravity.

  In the surface shape measuring apparatus according to the sixth aspect of the present invention, in the fifth aspect, the elastic member is a compression spring.

  In the surface shape measuring apparatus according to the seventh aspect of the present invention, in the fifth aspect or the sixth aspect, the elastic members supporting the weight of the moving body are arranged at three locations, and the center of gravity of the moving body is in plan view, It enters the area surrounded by three points.

  In the surface shape measuring device according to the eighth aspect of the present invention, in any one of the first aspect to the seventh aspect, the moving body and the second guide mechanism are connected using a piano wire, Arranged along the linear motion direction.

  A surface shape measuring apparatus according to a ninth aspect of the present invention is the surface shape measuring apparatus according to any one of the first to eighth aspects, further comprising a base and a column erected on the upper part of the base, and the detector is a column. The linear motor moves the column relative to the base along a first direction orthogonal to the longitudinal direction of the column, and the first guide mechanism extends along the first direction to detect the column and the detection. The moving body including the container is slidably guided.

  The surface shape measuring apparatus according to a tenth aspect of the present invention further includes a drive unit that moves the detector in a second direction orthogonal to the linear motion direction of the linear motor in the ninth aspect.

  The surface shape measuring apparatus according to an eleventh aspect of the present invention is the surface shape measuring apparatus according to any one of the first to eighth aspects, wherein the base, the weighing scale on which the object to be measured is placed, and the gravity more than the first guide mechanism. An elevating mechanism disposed below the direction, and a control means for controlling the elevating operation of the elevating mechanism according to the measurement result of the weighing scale, the linear motor moves the weighing scale relative to the base, The first guide mechanism extends along the first direction and slides and guides the moving body including the weighing scale and the object to be measured, and the control means biases the load corresponding to the weight of the object to be measured. The elevating mechanism is controlled so as to cancel out by expansion and contraction of the means.

  According to the tenth aspect, the magnitude of the force acting in the direction to cancel the weight load is actively adjusted according to the weight of the object to be measured. As a result, it is not necessary to secure excessive thrust of the linear motor, and excessive specification of the linear motor can be avoided.

  In the eleventh aspect of the surface shape measuring apparatus according to the twelfth aspect of the present invention, the elevating mechanism is disposed below the gravitational direction of the second guide mechanism.

  In the eleventh aspect of the surface shape measuring apparatus according to the thirteenth aspect of the present invention, the elevating mechanism is disposed between the second guide mechanism and the urging means.

  According to the present invention, the weight load acting on the sliding contact surface of the sliding guide can be reduced, and the frictional resistance of the sliding guide can be reduced. Further, according to the present invention, high straightness accuracy can be realized.

It is a front view which shows the structure of the surface shape measuring apparatus which concerns on 1st Embodiment of this invention. It is a left view of the surface shape measuring apparatus shown in FIG. FIG. 3 is a sectional view taken along line 3-3 in FIG. 1. It is a block diagram which shows the structure of the control system of the surface shape measuring apparatus which concerns on 1st Embodiment. It is a front view which shows the principal part of the surface shape measuring apparatus which concerns on 2nd Embodiment of this invention. It is a left view of the surface shape measuring apparatus shown in FIG. It is a front view which shows the principal part of the surface shape measuring apparatus which concerns on 3rd Embodiment of this invention. It is a left view of the surface shape measuring apparatus shown in FIG. FIG. 9 is a cross-sectional view taken along line 9-9 in FIG. 7. It is a block diagram which shows the structure of the control system of the surface shape measuring apparatus which concerns on 3rd Embodiment. It is a front view which shows the principal part of the surface shape measuring apparatus which concerns on 4th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<< First Embodiment >>
FIG. 1 is a front view showing a configuration of a surface shape measuring apparatus 10 according to the first embodiment of the present invention. A surface shape measuring apparatus 10 shown in FIG. 1 is a contact-type surface roughness measuring machine, and includes a base 12, a column 14 provided upright on the base 12, a detector 16 supported by the column 14, And a linear motor 20 that moves the column 14 relative to the base 12.

  The linear motor 20 is a power source that moves the column 14 in a direction orthogonal to the longitudinal direction of the column 14. In FIG. 1, the direction parallel to the linear motion direction of the linear motor 20 is defined as the X-axis direction, and the longitudinal direction of the column 14 is defined as the Z-axis direction. The linear motor 20 is a shaft motor including a shaft 22 and a mover 24.

  The detector 16 includes a measuring element 32 having a stylus 30 at the tip, and a transducer (not shown) that converts the displacement of the stylus 30 into an electrical signal. The stylus 30 contacts the surface of the object to be measured (not shown) and is displaced following the shape of the surface of the object to be measured. The transducer may be configured to use a differential transformer, for example. The detector 16 is attached to the movable part 34 of the column 14.

  The column 14 is an elevating mechanism that moves the detector 16 in the vertical direction (Z-axis direction) in FIG. The column 14 includes a ball screw 36 that moves the movable portion 34 up and down, and a lift motor 38. The rotating shaft of the lifting / lowering motor 38 is connected to the ball screw 36. When the ball screw 36 is rotated by the power of the elevating motor 38, the movable portion 34 moves in the vertical direction in FIG. The detector 16 attached to the movable part 34 moves in the vertical direction in FIG. 1 together with the movable part 34. The column 14 is moved in the X-axis direction by the thrust of the linear motor 20 together with the detector 16.

  The surface shape measuring apparatus 10 includes a guide base 40 that slides and guides a column 14 that is moved by the thrust of the linear motor 20 in the X-axis direction, and a slider 42. The guide base 40 extends along the X-axis direction and is disposed in parallel with the shaft 22 of the linear motor 20. The X-axis direction in this case corresponds to the “first direction”. Two support members 44 that support the linear motor 20 and the guide base 40 are erected on the base 12 of the surface shape measuring apparatus 10. Both ends of the guide base 40 and both ends of the shaft 22 of the linear motor 20 are supported by support members 44.

  The slider 42 is slidably supported on the guide base 40. The slider 42 is connected to the column 14. The guide base 40 and the slider 42 are examples of a “first guide mechanism”.

  The surface shape measuring apparatus 10 further includes a linear guide 50 disposed below the column 14 and a connection structure 60 that elastically connects the column 14 and the linear guide 50. The linear guide 50 includes a guide rail 52 and a carriage 54. The guide rail 52 is disposed along the X-axis direction and is fixed to the upper surface of the base 12. That is, the linear guide 50 is disposed below the guide base 40 in the direction of gravity, and the guide rail 52, the guide base 40, and the shaft 22 of the linear motor 20 are disposed in parallel to each other. . The linear guide 50 is an example of a “second guide mechanism”.

  The connecting structure 60 is disposed between the column 14 and the linear guide 50. The column 14 is connected to the carriage 54 of the linear guide 50 via the connecting structure 60. The connection structure part 60 has a structure in which a spring 64 is disposed between the first plate 61 and the second plate 62. The spring 64 is a compression spring that is elastically deformed in the Z-axis direction. The first plate 61 is fixed to the upper surface of the carriage 54. The second plate 62 is disposed to face the first plate 61 with a spring 64 interposed therebetween. The column 14 is placed on the second plate 62, and the lower end of the column 14 is fixed to the second plate 62. The connecting structure 60 including the spring 64 is an example of “biasing means”. The spring 64 is an example of an “elastic member”. You may use elastic members other than a spring.

  FIG. 2 is a left side view of the surface shape measuring apparatus 10 shown in FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 2 and 3, the support member 44 is not shown.

  As shown in FIG. 2, the slider 42 is connected to the mover 24 of the linear motor 20.

  The column 14, the detector 16, and the slider 42 can be a moving body that moves integrally with the thrust of the linear motor 20.

  The column 14 is disposed on the carriage 54 of the linear guide 50 via a spring 64. The spring 64 is attached to the carriage 54 of the linear guide 50 via the first plate 61. The spring 64 mounted on the carriage 54 supports the weight of the moving body including the slider 42, the column 14, and the detector 16, and changes the load corresponding to the weight of the moving body to a force in the direction opposite to the gravity direction. It plays a role to act on. That is, the spring 64 reduces the frictional resistance of the sliding portion by causing the linear guide 50 to bear the weight load of the moving body that should originally have been applied to the sliding portion between the guide base 40 and the slider 42. Fulfills the function. Further, the spring 64 functions to absorb swell and vibration caused by the ball entering and leaving the linear guide 50.

  The linear guide 50 supports the moving body including the column 14 and guides the moving body in the X-axis direction. The carriage 54 and the column 14 of the linear guide 50 are connected using a piano wire 66. One end of the piano wire 66 is fixed to the first plate 61 via the first fixing portion 61A. The other end portion of the piano wire 66 is fixed to the second plate 62 via the second fixing portion 62A. The carriage 54 is pulled by a moving body such as the slider 42 and the column 14 via the piano wire 66.

  The piano wire 66 is connected in parallel with the moving direction of the moving body such as the slider 42 and the column 14. As a result, the piano wire 66 is difficult to transmit vibration and undulation in the direction of gravity. Further, the spring 64 functions to absorb swell and vibration caused by the ball entering and leaving the linear guide 50.

  A plurality of springs 64 are preferably arranged, and in particular, as shown in FIG. 3, a configuration that uses three springs 64 to support the weight of the moving body in a balanced manner is preferable. In the present embodiment, the springs 64 that support the weight of the moving body are arranged at three locations, and the center of gravity of the moving body enters the inside of the region surrounded by the three three points in plan view. . As described above, the posture of the moving body is stabilized by arranging the three springs 64 so that the center of gravity of the moving body enters the inside of the three point constellation formed by the spring 64.

  FIG. 4 is a block diagram illustrating a configuration example of a control system of the surface shape measuring apparatus 10 according to the first embodiment.

  The surface shape measuring device 10 includes a control device 70, driver circuits 71 and 72, and a data processing device 80. The driver circuit 71 includes an amplifier that supplies electric power for driving the linear motor 20. The linear motor 20 is connected to the driver circuit 71. The driver circuit 72 includes an amplifier that supplies electric power for driving the elevating motor 38. The lift motor 38 is connected to the driver circuit 72.

  The control device 70 comprehensively controls the operation of the surface shape measuring device 10. The control device 70 includes, for example, various arithmetic processing circuits including a CPU (central processing unit) and a storage device such as a memory. The control device 70 functions as a control unit by executing a predetermined program stored in advance. The function of the control device 70 can be realized using one or more processors. The processor can have various circuit forms such as a CPU, a programmable logic device (PLD) such as a field programmable gate array (FPGA), and an application specific integrated circuit (ASIC).

  The control device 70 is connected to driver circuits 71 and 72. The control device 70 can output a control signal to each of the driver circuits 71 and 72. The driver circuit 71 supplies power to the linear motor 20 in accordance with a command from the control device 70. The driver circuit 72 supplies power to the lifting motor 38 in accordance with a command from the control device 70. Note that the driver circuits 71 and 72 may be included in the control device 70.

  The control device 70 is connected to the detector 16 and the data processing device 80. The detector 16 is connected to the data processing device 80. The signal output from the detector 16 is input to the data processing device 80.

  The data processing device 80 includes a processor that processes data obtained from the detector 16 and performs various calculations, and a storage device such as a memory that stores various information such as measurement data.

  The data processing device 80 analyzes the surface shape of the object to be measured based on the detection signal obtained from the detector 16. The data processing device 80 may be configured using a computer.

  The data processing device 80 is connected to the input device 82 and the display device 84. The input device 82 and the display device 84 function as a user interface. The input device 82 may be, for example, an operation button, a joystick, a keyboard, a mouse, a touch panel, or an appropriate combination thereof. The user can input various instructions such as measurement conditions and analysis conditions by operating the input device 82.

  The display device 84 may be, for example, a liquid crystal display or an organic EL (organic electro-luminescence: OEL) display. Various types of information such as measurement result information can be displayed on the display device 84. The data processing device 80 may be connected to a printer (not shown). The control device 70 may include the function of the data processing device 80. For example, the functions of the control device 70 and the data processing device 80 may be realized by a single computer.

  According to the surface shape measuring apparatus 10 configured as described above, the slider 42 becomes a sliding guide along the guide base 40, and by the action of the spring 64 disposed between the column 14 and the linear guide 50, The swell and vibration caused by the linear guide 50 are removed.

  At this time, since the force due to the weight of the moving body including the slider 42 is canceled by the force of the spring 64, the friction resistance is reduced and the guide base 40 is less likely to bend. The connecting structure 60 using the spring 64 functions as a load reducing unit that applies a force to the moving body to cancel the weight load of the moving body so as to reduce the weight load of the moving body.

  According to the first embodiment, it is possible to use the guide base 40 with low rigidity, and it is possible to achieve high straightness accuracy even with the guide base 40 with low rigidity.

<< Second Embodiment >>
FIG. 5 is a front view showing a main part of the surface shape measuring apparatus according to the second embodiment of the present invention. 6 is a left side view of the surface shape measuring apparatus shown in FIG.

  5 and 6, elements that are the same as or similar to the configuration of the first embodiment described in FIGS. 1 to 4 are assigned the same reference numerals, and redundant descriptions are omitted. Differences from the first embodiment will be described.

  In the surface shape measuring apparatus 100 according to the second embodiment shown in FIGS. 5 and 6, a drive unit 102 that drives the detector 16 in the X-axis direction is attached to the column 14, and the detector 16 and the drive unit 102. The column 14 on which is mounted is moved in the Y-axis direction by the linear motor 20. The Y-axis direction is a direction orthogonal to the X-axis direction and the Z-axis direction. In the case of the second embodiment, the Y-axis direction corresponds to the “first direction”, and the X-axis direction corresponds to the “second direction”.

  The shaft 22, the guide base 40, and the linear guide 50 of the linear motor 20 are arranged along the Y-axis direction. In FIG. 5, illustrations of the support members that support both ends of the shaft 22 and the guide base 40 of the linear motor 20 are omitted.

  The detector 16 is attached to the drive unit 102. The drive unit 102 includes a support mechanism (not shown) that supports the detector 16 movably along the X-axis direction, and a motor (not shown). The motor may be a rotary motor or a linear motor. The drive unit 102 is fixed to the movable unit 34 of the column 14. The drive unit 102 is connected to the control device 70 (see FIG. 4) via a driver circuit (not shown), and is driven according to a command from the control device 70.

  The detector 16, the drive unit 102, the column 14, and the slider 42 become a moving body that moves integrally along the Y-axis direction by the thrust of the linear motor 20.

  The connecting structure 60 including the spring 64 supports the weight of the moving body that moves along the guide base 40, and urges the moving body in the direction opposite to the direction of gravity by the force of the spring 64 to thereby guide the base. Counterweight load to 40.

  According to the surface shape measuring apparatus 110 according to the second embodiment, the same effect as that of the first embodiment can be obtained, and a highly accurate measurement axis can be realized by both the X axis and the Y axis.

<< Third Embodiment >>
FIG. 7: is a front view which shows the principal part of the surface shape measuring apparatus which concerns on 3rd Embodiment of this invention. A surface shape measuring apparatus 110 shown in FIG. 7 is a workpiece moving type surface shape measuring apparatus. In FIG. 7, the portion of the base 12 is schematically indicated by a broken line. FIG. 8 is a left side view of the surface shape measuring apparatus 110 shown in FIG. In FIG. 8, illustrations of support members that support both ends of the shaft 22 and the guide base 40 of the linear motor 20 are omitted. Further, the base is not shown in FIG. 9 is a cross-sectional view taken along line 9-9 of FIG.

  In the surface shape measuring apparatus 110 shown in FIGS. 7 to 9, the same or similar elements as those shown in FIGS. 1 to 4 are denoted by the same reference numerals, and redundant description is omitted.

  The surface shape measuring apparatus 110 shown in FIGS. 7 to 9 includes a weigh scale 112 that measures the weight of the workpiece W that is the object to be measured, and an elevating mechanism 114 that adjusts the amount of expansion and contraction of the spring 64 of the connecting structure 60. And an elevating motor 115 for driving the elevating mechanism 114.

  As shown in FIG. 8, the guide base 40 is disposed so as to surround the upper portion of the linear motor 20, and the slider 42 is connected to the mover 24 of the linear motor 20.

  The weight scale 112 is fixed to the slider 42. The workpiece W may be placed directly on the weighing scale 112 or may be set on the weighing scale 112 via a workpiece holder (not shown).

  The workpiece W, the weight scale 112, and the slider 42 become a moving body that moves integrally along the X-axis direction by the thrust of the linear motor 20. The weight of the moving body can change depending on the weight of the workpiece W.

  The detector 16 is attached to a column (not shown). In the third embodiment, the column may be fixed so as not to move with respect to the base 12.

  The elevating mechanism 114 is disposed below the linear guide 50. That is, the guide rail 52 of the linear guide 50 is placed on the lifting mechanism 114.

  The elevating mechanism 114 has a structure for moving the elevating block 117 in the vertical direction using the slope of the wedge-shaped slide block 116. By rotating the screw rod 118 by the elevating motor 115, the slide block 116 is moved, and the elevating block 117 is moved up and down. In addition, it is an example of the structure of the raising / lowering mechanism 114, and is not restricted to the example of illustration, The raising / lowering apparatus of various forms which can be electrically controlled can be employ | adopted.

  The guide base 40 and the linear motor 20 may be disposed below the upper surface 12A of the base 12. For example, the base 12 includes a recess 12B that accommodates the guide base 40, the linear motor 20, the linear guide 50, the lifting mechanism 114, and the like. Both ends of the guide base 40 and the linear motor 20 are supported by a column member (not shown) provided in the recess 12B so as to be movable in the Z direction.

  A part or all of the weighing scale 112 may be disposed so as to be exposed above the upper surface 12A of the base 12. The upper side of the guide base 40 is covered with a bellows (not shown).

  The workpiece W is placed on the weighing scale 112, and the weight of the workpiece W is measured by the weighing scale 112. The lifting mechanism 114 is raised and lowered according to the weight measured by the weight scale 112.

  The initial load corresponding to the weight of the slider 42 and the weigh scale 112 when the work W is not placed is canceled (canceled) in advance by applying a force that pushes the slider 42 in the direction opposite to the direction of gravity by the spring 64. Then, when the workpiece W is placed on the weighing scale 112, the weight of the workpiece W is measured by the weighing scale 112, and the lifting mechanism 114 is operated according to the weight of the workpiece W, whereby the amount of expansion and contraction of the spring 64 is reached. To cancel the load corresponding to the weight of the workpiece W. Note that the weight of the work holder when using a work holder (not shown) may be included in the weight of the work W or may be included in the weight of the initial load.

  In the case of such a workpiece movement type surface shape measuring apparatus 110, the center of gravity of the moving body including the slider 42 changes depending on the form of the workpiece W. However, in plan view, the three are arranged at three points that hold the center of gravity inside. Since the slider 42 is pushed up by the spring 64, the posture of the slider 42 is stabilized.

  FIG. 10 is a block diagram illustrating a configuration of a control system of the surface shape measuring apparatus according to the third embodiment. 10, elements that are the same as or similar to those shown in FIG. 4 are given the same reference numerals, and redundant descriptions are omitted.

  As shown in FIG. 10, the scale 112 is connected to the data processing device 80. Information on the workpiece weight obtained from the weigh scale 112 is sent to the data processing device 80.

  The surface shape measuring apparatus 110 includes a driver circuit 73 that supplies power to the lifting motor 115. The control device 70 is connected to the driver circuit 73.

  The data processing device 80 calculates the amount of movement of the elevating mechanism 114 based on the information on the weight of the workpiece W measured by the weigh scale 112. The control device 70 calculates the amount of rotation of the lifting / lowering motor 115 necessary for the movement of the lifting / lowering mechanism 114 and transmits a control signal for driving the motor to the driver circuit 73. The combination of the data processing device 80 and the control device 70 is an example of a “control unit” that controls the lifting operation of the lifting mechanism 114.

  According to the surface shape measuring apparatus 120 according to the third embodiment, the lifting mechanism 114 is automatically controlled so as to cancel the load corresponding to the weight of the workpiece W in accordance with the weight of the workpiece W. With such a configuration, it is not necessary to secure excessive thrust in the linear motor 20, and excessive specification of the linear motor 20 can be avoided.

<< 4th Embodiment >>
FIG. 11: is a front view which shows the principal part of the surface shape measuring apparatus which concerns on 4th Embodiment of this invention. 11, elements that are the same as or similar to those shown in FIGS. 8 to 9 are given the same reference numerals, and redundant descriptions are omitted. Differences from the third embodiment will be described.

  In the surface shape measuring apparatus 120 shown in FIG. 11, an elevating mechanism 124 that adjusts the amount of expansion and contraction of the spring 64 is disposed above the carriage 54 of the linear guide 50 and below the slider 42.

  The guide rail 52 of the linear guide 50 is fixed to the base 12. The elevating mechanism 124 is fixed on the carriage 54. The first plate 61 of the connecting structure 60 is fixed to the lifting block 117 of the lifting mechanism 124.

  The configuration of the control system of the surface shape measuring apparatus 120 according to the fourth embodiment is the same as that of the third embodiment described with reference to FIG. According to the surface shape measuring apparatus 120 according to the fourth embodiment shown in FIG. 10, in addition to obtaining the same effect as that of the third embodiment, a lifting mechanism smaller than that of the third embodiment can be adopted.

<< Modification 1 >>
In place of the linear guide 50 in each of the above-described embodiments, a guide mechanism that generally reduces friction, such as a cross roller guide, a linear bush, or a roller guide, can be employed.

<< Modification 2 >>
Instead of the spring 64 in each embodiment described above, an air cylinder, an air bearing cylinder, or the like may be employed. By using an air cylinder or an air bearing cylinder instead of the spring 64, the insulation against vibration can be further improved.

<< Modification 3 >>
In each of the above-described embodiments, the contact-type detector 16 has been exemplified. However, instead of the contact-type detector 16, a non-contact-type detector may be employed. For example, the non-contact detector may be configured to detect the surface shape by irradiating the surface of the non-measurement object with laser light and receiving the reflected light.

<< Modification 4 >>
In the workpiece movement type configuration described in the third and fourth embodiments, the detector 16 may be attached to the drive unit 102 (see FIG. 5). For example, by adopting a configuration in which the moving direction of the detector 16 by the drive unit 102 is the X-axis direction and the moving direction of the workpiece W by the linear motor 20 is the Y-axis direction, both axes in the X-axis direction and the Y-axis direction are adopted. Direction measurement can be realized with high accuracy.

<< Modification 5 >>
The vertical positional relationship between the lifting mechanism 124 and the connecting structure 60 shown in FIG. 10 may be reversed. That is, the connection structure 60 may be fixed on the carriage 54, and the elevating mechanism 124 may be disposed between the second plate 62 of the connection structure 60 and the slider 42.

《Other application examples》
The present invention is not limited to the surface roughness measuring device but can be applied to various surface shape measuring devices such as a contour shape measuring device, a roundness measuring device, and a three-dimensional coordinate measuring device. In this specification, the term “surface shape measuring device” includes the concept of various devices such as a surface roughness measuring device, a contour shape measuring device, a roundness measuring device, and a three-dimensional coordinate measuring device. The terms surface roughness measuring device or contour shape measuring device can selectively measure surface roughness and contour shape, as well as surface roughness and contour shape integrated measuring device that can measure surface roughness and contour shape simultaneously. The concept of a complex surface roughness / contour shape combined measuring device is included.

  The embodiments of the present invention have been described above. However, the present invention is not limited to the above examples, and various improvements and modifications may be made without departing from the scope of the present invention. .

10, 100, 110, 120 ... surface shape measuring device 12 ... base 14 ... column 16 ... detector 20 ... linear motor 22 ... shaft 24 ... mover 30 ... -Stylus 32 ... Measuring element 40 ... Guide base 42 ... Slider 50 ... Linear guide 52 ... Guide rail 54 ... Carriage 64 ... Spring 66 ... Piano wire 70 ... Control devices 71, 72, 73 ... Driver circuit 80 ... Data processing device 102 ... Driver 112 ... Weigh scales 114,124 ... Elevating mechanism 115 ... Elevating motor

Claims (13)

A detector that outputs a signal corresponding to the shape of the surface of the object to be measured;
A linear motor for relatively moving the object to be measured and the detector;
A first guide mechanism that slides and guides a moving body that moves by the thrust of the linear motor in a first direction parallel to the linear motion direction of the linear motor;
The second guide mechanism and the movable body are arranged below the gravitational direction, support the movable body, and guide the movable body in the first direction parallel to the linear motion direction of the linear motor. A guide mechanism;
An urging means disposed between the second guide mechanism and the movable body, and applying a force acting on the movable body in a direction opposite to the direction of gravity;
A surface shape measuring device comprising: The first guide mechanism includes:
A guide base disposed parallel to the linear motion direction of the linear motor;
A slider slidably supported on the guide base;
The surface shape measuring apparatus according to claim 1, comprising:   The surface shape measuring apparatus according to claim 1, wherein the second guide mechanism is a linear guide.   4. The surface shape measuring apparatus according to claim 1, wherein the urging unit applies a force to the moving body to cancel a weight load of the moving body with respect to the first guide mechanism. 5.   The surface shape measuring apparatus according to any one of claims 1 to 4, wherein the urging unit includes an elastic member that is elastically deformed in a gravitational direction.   The surface shape measuring apparatus according to claim 5, wherein the elastic member is a compression spring. The elastic members that support the weight of the moving body are arranged at three locations,
The surface shape measuring apparatus according to claim 5 or 6, wherein a center of gravity of the moving body enters an area surrounded by the three points in the three places in a plan view. The movable body and the second guide mechanism are connected using a piano wire,
The said piano wire is a surface shape measuring apparatus as described in any one of Claim 1 to 7 arrange | positioned along the said linear motion direction. Base and
A column erected on top of the base;
Further comprising
The detector is supported by the column;
The linear motor moves the column relative to the base along the first direction orthogonal to the longitudinal direction of the column,
9. The surface shape according to claim 1, wherein the first guide mechanism extends along the first direction and slides and guides the moving body including the column and the detector. measuring device.   The surface shape measuring apparatus according to claim 9, further comprising a drive unit that moves the detector in a second direction orthogonal to the linear motion direction of the linear motor. Base and
A weighing scale on which the object to be measured is placed;
An elevating mechanism disposed below the first guide mechanism in the direction of gravity;
Control means for controlling the lifting operation of the lifting mechanism according to the measurement result of the weighing scale;
Further comprising
The linear motor moves the scale relative to the base,
The first guide mechanism extends along the first direction, and slides and guides the moving body including the weighing scale and the object to be measured.
The surface shape measuring apparatus according to claim 1, wherein the control unit operates the elevating mechanism so as to cancel a load corresponding to a weight of the object to be measured by expansion and contraction of the biasing unit.   The surface shape measuring apparatus according to claim 11, wherein the elevating mechanism is disposed below the second guide mechanism in the gravity direction.   The surface shape measuring apparatus according to claim 11, wherein the elevating mechanism is disposed between the second guide mechanism and the urging means.

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