JP3056435U - Load measuring device - Google Patents

Abstract

(57) [Problem] To provide an accurate contact of the axis of a measurement jig of a sensor of a load measuring device with the center of a test object even when the test object is small. An XY table (2) on which a DUT (1) is placed.
A CCD camera, which is a video photographing means 6, is mounted above and in parallel with a predetermined distance from the axis of the measuring jig 5 of the pressure sensor 3, which is vertically movably supported by the elevating mechanism 4. The video photographing means 6 is connected to a video monitor 7, and the XY table 2 is moved so that the center of the DUT 1 displayed on the video monitor 7 is the center of the monitor screen. Thereafter, by moving the XY table 2 by a predetermined distance, the axis 5 of the measuring jig of the pressure sensor 3 attached in parallel with the video photographing means 6 is accurately positioned directly above the DUT. Be able to do it.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a load measuring device for measuring a load applied to a DUT by pressing a sensor.

[0002]

[Prior art]

 For example, a pressure (compression force) sensor 3 is supported by a lifting mechanism 4 above the measurement table 2 as shown in FIG. There is something.

An elevating mechanism 4 supports the pressure sensor 3 movably in the vertical direction, and based on a displacement detected when the pressure sensor 3 is pressed against the DUT 1 placed on the measurement table 2. Then, the load applied to the test object is measured.

[0004] Load measuring devices of this type are used in various fields such as measurement of pressing and insertion pressures of small mechanical parts such as switches, keyboards and connectors.

By the way, in such a measurement, conventionally, as shown in FIG. 6, positioning is visually performed such that the tip of a measurement jig 5 attached to the pressure sensor 3 is directly above the DUT 1. Was.

[0006]

[Problems to be solved by the invention]

 However, the above-described visual positioning has a problem that, for example, it is not possible to cope with components that are becoming lighter, thinner and smaller due to the spread of mobile devices such as mobile phones in recent years.

In other words, if the DUT becomes small and has a size that is not so different from the tip diameter of the measuring jig, the jig hides the DUT and positioning of the tip cannot be performed well. In other words, if the DUT is small, the center axis of the jig will not be exactly above the center axis of the DUT due to the blind spot created by the measurement jig, and accurate measurement results will not be obtained. There was a problem.

Therefore, an object of the present invention is to enable accurate positioning even when the DUT is small.

[0009]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, a pressure sensor is vertically movably supported by a lifting mechanism above a measurement table on which a DUT is placed, and a measuring device attached to the pressure sensor is provided. In a load measuring device that presses the tip of the jig against the DUT on the table and measures the load based on the displacement, the lifting mechanism is placed at a predetermined distance from the axis of the measuring jig of the pressure sensor. A video monitor for displaying an image captured by the video capturing unit; a video monitor for displaying images captured by the video capturing unit; Then, the photographed DUT is displayed on the monitor screen, and the center axis of the displayed DUT is made to coincide with the center axis of the monitor display screen. Moving the mechanism by a predetermined distance at the adopting the configuration was Unishi by positioning the pressure sensor.

By employing such a configuration, the center axis of the DUT photographed by the video photographing means is set to be the center of the frame of the monitor display screen. Next, when the measuring table or the elevating mechanism is moved by the predetermined distance, the video photographing means is attached at a predetermined distance in parallel with the axis of the measuring jig of the pressure sensor. The axis of the measuring jig can be positioned directly above the DUT.

[0011]

[Embodiment of the invention]

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a first embodiment.

In this embodiment, an X-Y table 2 on which a DUT 1 is placed, an elevating mechanism 4 supporting a pressure sensor 3 and a video photographing means 6, a video monitor 7, a control device 8, and a measurement amplifier 9 It is composed of

The XY table 2 includes an X-axis drive motor 10 and a Y-axis drive motor 11. Further, sensors 12 and 13 such as a rotary encoder and a linear scale are provided as position detection sensors in the X-axis and Y-axis directions, respectively. The detection sensors 12 and 13 enable positioning of the XY table 2 and detection of the origin position.

The lifting mechanism 4 includes a lifting motor 14, a ball screw 15 mounted on the motor shaft thereof, and a mounting plate 16 mounted on the ball screw 15. The mounting plate 16 is engaged with the ball screw 15. Screw groove is formed.

The pressure sensor 3 and the video photographing means 6 are mounted on the mounting plate 16.

The pressure sensor 3 uses a load cell, and is equipped with a measuring jig 5 as shown in FIG.

In this embodiment, the video photographing means 6 is a small CCD camera mounted with the lens 18 facing downward as shown in FIG. 1, and the optical axis of the lens and the pressure sensor as shown in FIG. The axis of the measuring jig 5 is attached in parallel at a predetermined distance (X1, Y1).

A sensor 17 such as a rotary encoder is attached to the ball screw 15 as a position sensor in the Z-axis direction.

The video monitor 7 is connected to the video photographing means 6 and displays an image photographed by the CCD camera.

The control device 8 includes, for example, a control computer 20 and an XY amplifier 21 for driving a table.

The outputs of the position sensors 12 and 13 of the XY table 2 in the X-axis direction and the Y-axis direction and the outputs of the position sensor 17 of the lifting mechanism 4 in the Z-axis direction are input to the computer 20. And outputs a control output to the XY amplifier 21 based on these inputs.

The XY amplifier 21 outputs drive outputs to the X-axis motor 10 and Y-axis motor 11 of the XY table 2 and the Z-axis drive motor 14 of the lifting mechanism 4 based on the signal.

Therefore, by operating the control computer 20, the XY table 2 can be arbitrarily moved.

The control computer 20 is connected to the measurement amplifier 9 via an interface board.

The measuring amplifier 9 measures the output of the pressure sensor 3 under the control of the control computer 20. The measured values can be printed out by a printer or recorded on a floppy or other recording media.

This embodiment is configured as described above. Next, the operation of the present invention will be described by describing a measuring method of the load measuring device.

In this measuring instrument, the measuring jig of the pressure sensor 3 is determined based on the distance (X1, Y1) between the optical axis of the video photographing means 6 and the axis of the measuring jig 5 of the pressure sensor 3 which is set in advance. The position of the tool 5 is calculated.

That is, first, the DUT 1 is placed on the XY table 2. Next, with the lifting mechanism 4 raised, the DUT 1 placed on the XY table 2 is moved from the origin position (assuming that the XY table 2 is at the origin position) to the video photographing means 6. Move to the position where you can see. Then, the moving position is finely adjusted so that the central axis of the DUT 1 coincides with the central axis of the video monitor 7 screen.

At this time, the video photographing means 6 can also photograph and enlarge the DUT 1 from directly above, so that even if the DUT 1 is small, its center axis coincides with the center axis of the video monitor 7 screen. And no parallax occurs.

For this reason, as shown in FIG. 3, the center axis of the DUT 1 can be matched with the center axis of the display screen of the video monitor 7. Then, from the coincident coordinates (Bx, By), a predetermined distance between the video photographing means 6 and the axis of the measuring jig 5 of the pressure sensor 3 is obtained from the following equation: Ax = Bx-X1 Ay = By-Y1 By subtracting (X1, Y1), the coordinates (Ax, Ay) at which the axis of the measuring jig 5 of the pressure sensor 3 coincides with the center axis of the DUT 1 can be obtained.

Therefore, by moving the XY table 2 from the coincident coordinates (Bx, By) to the coordinates minus (X1, Y1), the axis of the measuring jig 5 of the pressure sensor 3 and the axis The central axis of the test article 1 can be made coincident. This is because the pressure sensor 3 and the video photographing means 6 were attached in parallel at a predetermined distance.

Therefore, when the elevating mechanism 4 is lowered and the tip of the measuring jig 5 of the pressure sensor 3 is pressed against the DUT 1 on the table 2 and the displacement is measured by the pressure sensor 3, accurate measurement is obtained. Can be performed.

As described above, by performing positioning using the video photographing means 6, parallax can be prevented from being generated. Therefore, accurate measurement can be performed by easily aligning the axis of the measuring jig 5 of the pressure sensor 3 with the center axis of the DUT 1. For this reason, it can be used as an evaluator for physical properties.

In the first embodiment, the case where the measurement table 2 moves is described. Next, as the second embodiment, the case where the lifting mechanism 4 moves left and right will be described.

As shown in FIG. 4, the load measuring device of this embodiment has a configuration in which the lifting mechanism 4 is supported on a linear way 30 erected along the X-axis direction of the measuring table 2.

The elevating mechanism 4 is supported by the linear way 30 so as to be movable left and right, and the moving position thereof can be detected by the position sensor 15.

The elevating mechanism 4 is configured such that the inner cylinder 16 having the pressure sensor (load cell) 3 attached to the tip thereof can be extended and contracted by a ball screw attached to the motor 14 as in the first embodiment.

A CCD camera is attached to the case containing the inner cylinder 16 as a video photographing means 6 with a mounting bracket, and the video photographing means 6 is connected to the axis of the measurement jig 5 of the pressure sensor 3. They are mounted in parallel and at a predetermined distance (X1).

As other control circuits and the like can be the same as those in the first embodiment, the description is omitted.

This configuration is configured as described above. As shown in FIG. 4, this measuring apparatus includes a plurality of keys such as a keyboard arranged in a row in the measuring table 2 as a DUT 1 in a horizontal direction. Can be used for measuring the pressure of the objects arranged in a row.

In this case, when the moving position is fine-tuned so that the central axis of the key top photographed by the video photographing means 6 coincides with the central axis of the display screen of the video monitor 7, the coordinate (Bx) from the coincident coordinate (Bx) Similarly to the first embodiment, if the lifting mechanism 4 is moved to the coordinates minus (X1) by the linear way, the axis 5 of the measuring jig of the pressure sensor 3 can be made coincident with the center axis of the key.

Since the center axes can be made to coincide with each other in this manner, if the lifting mechanism 4 is lowered and the tip of the measuring jig 5 attached to the pressure sensor 3 is pressed against the key of the keyboard, the displacement is measured by the pressure sensor 3. Can be measured.

When the measurement of one key is completed, the linear way 30 is moved, the next key is photographed by the video photographing means 6, and the measurement is performed in the same procedure.

As described above, the measurement can also be performed by moving the lifting mechanism 4 right and left.

If a cross gauge is provided on the lens of the video photographing means 6 or on the screen of the video monitor 7, the center axis of the DUT 1 coincides with the center axis of the display screen of the video monitor 7. It is preferable because it is easy to perform.

Further, in the embodiment, the CCD camera is used as the video shooting means, but the video shooting means is not limited to this. For example, a fiber camera using an optical fiber for the light guide or a small image pickup tube may be used.

[0048]

[Effect of the invention]

 With this configuration, the tip of the pressure sensor jig can be positioned directly above the center axis of the DUT, and accurate measurement results can be obtained, even if the DUT is small, by using the above configuration. .

[Brief description of the drawings]

FIG. 1 is a block diagram of a first embodiment.

FIG. 2 is an operation explanatory view of the first embodiment.

FIG. 3 is a diagram illustrating the operation of the first embodiment.

FIG. 4 is a front view of a second embodiment.

FIG. 5 is a front view of a conventional example.

FIG. 6 is a diagram illustrating the operation of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 DUT 2 Measurement table 3 Pressure sensor 4 Elevating mechanism 5 Measurement jig 6 Video photography means 7 Video monitor 8 Control device 9 Measurement amplifier 30 Linear way

Claims (1)

[Utility model registration claims] 1. A pressure sensor is movably supported in a vertical direction by a lifting mechanism above a measurement table on which a test object is placed, and a tip of a measurement jig attached to the pressure sensor is placed on the table. A load measuring device that presses against the test object and measures a load based on the displacement thereof; a video photographing unit attached to the lifting mechanism in parallel with a predetermined distance from an axis of a measuring jig of the pressure sensor; A video monitor for displaying an image captured by the video capturing means; and
After moving to the left and right, the test object is photographed by the video photographing means, the photographed test object is displayed on the monitor screen, and the center axis of the displayed test object is made to coincide with the center axis of the monitor display screen. And a load measuring device for positioning the pressure sensor by moving the measurement table or the lifting / lowering mechanism by the predetermined distance.