JPH0633009U - Ultrasonic potentiometer - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an ultrasonic potentiometer capable of keeping a constant gap between a magnetostrictive wire and a detection head with a relatively simple structure. [Structure] A slide sheet member is provided on both sides of the magnetostrictive line so as to be flush with the magnetostrictive line along the longitudinal direction of the magnetostrictive line, and the rigidity in the direction perpendicular to the plane and the rotational direction having the axis in the plane is small. The detection head is attached to the frame of the carriage through a leaf spring that has a large horizontal rigidity, and a slider is provided on the surface of the leaf spring that faces the slide sheet member. The slider is pressed against the slide sheet member by pressing.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an ultrasonic potentiometer, and more particularly, to an improved detection head.

[0002]

[Prior art]

 The applicant of the present invention, as a means for obtaining a position feedback signal corresponding to the position of a movable part such as a pointer or a recording pen in a non-contact manner, an ultrasonic wave propagating inside a magnetostrictive wire composed of a linear magnetostrictive material. An ultrasonic potentiometer using signals has been proposed (for example, Japanese Patent Publication No. 60-55020) and put into practical use. FIG. 3 is a sectional configuration explanatory view showing an example of the periphery of a detection head of such a conventional ultrasonic potentiometer. In the figure, 1 is a magnetostrictive wire formed in a ribbon shape, and one side is attached to the stepped surface 3 of the pedestal 2 so that the other side protrudes from the stepped surface 3 of the pedestal 2. . Reference numeral 4 denotes a guide plate, which is attached to the top surface 5 of the pedestal 2 so that one side of the guide plate faces the stepped surface 3 of the pedestal 2. A carriage 6 is movably fitted to a guide shaft 7 arranged parallel to the pedestal 2. A detection head 8 and a guide 9 are integrated with the carriage 6. The detection head 8 is formed in a U-shape so as to sandwich the side of the magnetostrictive wire 1 protruding from the stepped surface 3 of the pedestal 2 from both sides in a non-contact state. The guide 9 is formed in a U shape so that it slides while sandwiching the sides of the guide plate 4 protruding from the top surface 5 of the pedestal 2 from both sides.

In such a configuration, in order to secure the measurement accuracy of the ultrasonic potentiometer, it is necessary to keep the relative distance between the magnetostrictive wire 1 and the detection head 8 constant. This is because the position of the carriage 6 is obtained by measuring the ultrasonic wave propagation delay time based on the level of the output peak value as shown in FIG. 4, so that the output peak value changes as the relative distance changes. This is because the fluctuation of Δ causes an error of Δt in the measurement of the ultrasonic propagation delay time.

[0004]

[Problems to be solved by the device]

 However, in such a conventional configuration, the parallelism and flatness of the stepped portion 3 and the top surface 5 of the pedestal 2, the positional relationship of each portion, the dimensional error, the play of the sandwiched portion of the guide plate 4 and the guide 9, etc. Since it is affected, it is difficult to keep the relative distance between the magnetostrictive wire 1 and the detection head 8 constant, and a stable and highly accurate position signal cannot be obtained.

The present invention focuses on such a problem, and an object thereof is to provide an ultrasonic potentiometer capable of keeping a constant gap between a magnetostrictive wire and a detection head with a relatively simple structure. To provide.

[0006]

[Means for Solving the Problems]

 The present invention which achieves such an object is a sheet-shaped magnetostrictive wire and slides formed on both sides of the magnetostrictive wire along the longitudinal direction of the magnetostrictive wire so as to be flush with the magnetostrictive wire. The sheet member, the detection head that detects the ultrasonic signal propagating through the magnetostrictive line, the rigidity in the vertical direction of the plane and the rotation direction having the axis in the plane are small, and the rigidity in the horizontal direction of the plane is large, A leaf spring to which the detection head is attached so as to face the magnetostrictive wire in the central portion, a carriage having a square frame for attaching the leaf spring, and the facing portion of each slide sheet member of the leaf spring. Along the longitudinal direction of the slider and the slider attached to the slide seat member so that the frame of the carriage is urged to press the slider against the slide seat member via the leaf spring. In parallel The shaft is placed so that the carriage is movably engaged with it, and the magnetostrictive line and the slide seat are in a positional relationship that biases the frame of the carriage so as to press the slider against the slide seat member via the leaf spring. A guide that is arranged in parallel along the longitudinal direction of the supporting member and that is movably engaged with the carriage.

[0007]

[Action]

 The leaf spring attached to the frame of the carriage bends due to the positional relationship between the shaft and the guide with respect to the frame and the thickness of the slider, and presses the slider against the slide sheet member. The leaf spring to which the detection head is attached has low rigidity in the vertical direction of the plane and in the rotational direction having an axis in the plane, and high rigidity in the horizontal direction of the plane, so it slides along the carriage movement direction. Even if the surface has irregularities, the relative positional relationship between the magnetostrictive line and the detection head is always kept constant, and the displacement between the relative position of the carriage and the detection head due to friction is extremely small.

[0008]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a perspective view showing an embodiment of the present invention, and FIG. 2 is a sectional view showing an operating state of FIG. In these figures, 10 is a sheet-shaped magnetostrictive line, and 11 and 12 are formed so as to be flush with the magnetostrictive line 10 on both sides of the magnetostrictive line 10 along the longitudinal direction of the magnetostrictive line 10. These are slide sheet members, which can be formed, for example, by etching a Ni sheet, which is made of an electroformed material and has excellent magnetostrictive characteristics, into a predetermined shape. In this case, the magnetostrictive wire 10 and the slide sheet members 11 and 12 are connected by a plurality of discretely provided narrow connecting portions 13. One end of the magnetostrictive wire 10 is formed in a T shape, and a piezoelectric element for excitation or an exciting coil is attached to this portion, but it is not shown. Reference numeral 14 denotes a pedestal to which the slide sheet members 11 and 12 are attached, and a groove 15 for spatially separating the magnetostrictive wire 10 and the pedestal 14 is provided in a central portion facing the magnetostrictive wire 10. Reference numeral 16 is a detection head that detects an ultrasonic signal propagating through the magnetostrictive line. Reference numeral 17 is a leaf spring, which has vertical rigidity in the plane and an axis in the plane, has low rigidity in the rotational direction, and has large rigidity in the horizontal direction, and the detection head is arranged so as to face the magnetostrictive line 10 in the central portion. 16 is attached. Reference numeral 18 is a carriage, which is integrated with a square frame 19 for mounting the leaf spring 17. Reference numerals 20 and 21 denote sliders, which are attached to the portions of the leaf spring 17 facing the slide sheet members 11 and 12, respectively. Reference numeral 22 is a shaft, and 23 is a guide. The magnetostrictive wire 10 and the slide sheet members 11 and 12 are arranged in parallel along the longitudinal direction, the shaft 22 is movably inserted into the carriage 18, and the guide 23 is attached to the upper surface of the frame 19. Have been combined.

In such a configuration, the leaf spring 17 attached to the carriage 18 is biased by the shaft 22 and the guide 23 so as to press the sliders 20 and 21 against the slide sheet members 11 and 12. The leaf spring 17 is formed to have low rigidity in the vertical direction of the plane and in the rotation direction having an axis in the plane, and high rigidity in the horizontal direction of the plane.

As a result, when there is a height difference along the longitudinal direction of the mounting surface of the slide sheet members 11 and 12 of the pedestal 14, the magnetostrictive wire 10 is connected to the slide sheet members 11 and 12 and the connecting portion 13 thereof. Since they are connected with each other, the height changes similarly to the mounting surfaces of the slide sheet members 11 and 12, and the detection head 16 also has a small rigidity in the vertical direction of the leaf springs 17, so that The distance between the magnetostrictive line 10 and the detection head 16 is always kept constant regardless of the movement position of the carriage 18 according to the thickness of the sliders 20 and 21. Further, since the position spring 17 has a small rigidity in the vertical direction and a large rigidity in the horizontal direction, the frictional force generated on the sliding surface becomes small, and the carriage 18 and the detection head 16 associated with the friction are reduced. Relative positional displacement does not occur, assembly is easier than before, and highly accurate position detection signals can be obtained.

[0011]

[Effect of device]

 As described above, according to the present invention, it is possible to realize an ultrasonic potentiometer capable of maintaining a constant gap between the magnetostrictive line and the detection head with a relatively simple structure.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an operating state of FIG.

FIG. 3 is a structural explanatory view showing an example of a conventional ultrasonic potentiometer.

FIG. 4 is an operation explanatory diagram of FIG. 3;

[Explanation of symbols]

 10 Magnetostrictive wire 11, 12 Slide sheet member 13 Connection part 14 Pedestal 15 Groove 16 Detection head 17 Leaf spring 18 Carriage 19 Frame 20, 21 Slider 22 Shaft 23 Guide

Claims (1)

[Scope of utility model registration request] 1. A magnetostrictive wire formed in a sheet shape, and a slide sheet member formed on both sides of the magnetostrictive wire along the longitudinal direction of the magnetostrictive wire so as to be flush with the magnetostrictive wire, The detection head that detects the ultrasonic signal propagating through the wire and the rigidity in the direction perpendicular to the plane and in the rotation direction having an axis in the plane are small, and the rigidity in the horizontal direction of the plane is large, and the magnetostrictive wire faces the central portion. A leaf spring to which the detection head is attached, a carriage having a square frame for attaching the leaf spring, a slider attached to a portion of the leaf spring facing each slide sheet member, and a leaf spring. The slider is placed in parallel with the magnetostrictive line and the longitudinal direction of the slide sheet member in a positional relationship of energizing the frame of the carriage so as to press the slider against the slide sheet member, and the carriage moves. The shaft that can be engaged with the magnetostrictive wire and the longitudinal direction of the slide sheet member in a positional relationship that urges the frame of the carriage so as to press the slider against the slide sheet member via the leaf spring. Ultrasonic potentiometer, characterized in that the guides are arranged parallel to each other, and the guides are movably engaged with the carriage.
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