KR101077549B1 - Sliding variable resistor and wheatstone bridge and potentiometer experiment using the same - Google Patents

Abstract

The present invention relates to a slide type variable resistor with a vernier caliper and a Wheatstone bridge and potentiometer experimental apparatus using the same, and includes a resistor wound around a bobbin provided to dissipate heat in the form of a coil, The problem of heat generation is fundamentally solved, and by selecting the bobbin diameter and the thickness of the resistance wire properly, the zero point of the galvanometer can be found more accurately with the coil type slide type resistor, and the vernier caliper can be used to determine the zero point of the galvanometer. There is an effect that can easily and accurately measure the length ratio, the Wheatstone bridge test device and potentiometer test device using this also has the effect of improving the accuracy and precision of the measurement.

Slide, Variable Resistor, Wheatstone Bridge, Potentiometer, Experiment Device, Vernier Caliper, Bobbin, Coil

Description

SLIDING VARIABLE RESISTOR AND WHEATSTONE BRIDGE AND POTENTIOMETER EXPERIMENT USING THE SAME}

The present invention relates to a slide type variable resistor and a Wheatstone bridge and potentiometer experimental apparatus using the same. More specifically, the contact is connected to the sonar of the vernier caliper to accurately measure the length of the resistor contacted, thereby continuously measuring the variable resistance value. Whistle bridge and potentiometer experiments using a vernier caliper with a vernier caliper to reduce the measurement error in the Wheatstone bridge test device and potentiometer test device that can change the measurement accurately and accurately. Relates to a device.

In general, the variable resistor is classified into a slide type for continuously changing the resistance value and a step type for gradually changing the resistance value.

Sliding variable resistor, also known as volume, has been used for a long time for output control and is now widely used in vacuum cleaners, lamps, sound equipment, and experimental devices.

Such a slide type variable resistor has a straight type in which the resistor is formed in a straight shape and moves linearly while the contactor contacts the resistor, and a rotary type in which the resistor is formed in a circular shape and rotates while the contactor contacts the resistor.

In the conventional linear slide type variable resistor, the resistance of the resistor causes thermal deformation, and thus the resistance value varies depending on the temperature of the resistor. In addition, the resistance length increases when used for a long period of time, so that the ratio of the resistor length cannot be accurately obtained and the contact state with the contactor is poor. .

In particular, when using a conventional linear slide type variable resistor in a Wheatstone bridge test device or a potentiometer test device, it is necessary to accurately measure the length ratio of the resistor. Since the length of the galvanometer is 0 using a separate ruler, it is cumbersome. In addition, there is a problem that always includes a measurement error as the length of the resistor increases.

Accordingly, the present invention has been made to solve the problems of the prior art as described above, the contact wire is configured in the form of a coil wound tightly coiled to the coil provided to dissipate heat when using the resistor of the variable resistor and the contactor To provide a slide type variable resistor is provided with a vernier caliper connected to the son.

The present invention also provides a Wheatstone bridge experimental device equipped with the slide variable resistor and an experimental device for potentiometer.

In order to achieve the above object, the slide-type variable resistor according to the present invention is one resistor wire coated with an insulating material on a predetermined bobbin is wound with a coil, the coating portion of the upper coating in the longitudinal direction of the coil is peeled off; A contactor sliding in one end in contact with the peeled off resistor; A vernier caliper, the other end of which is inserted into a mechanically and electrically connected sonar and a mother inserted into the inner groove of the son and configured to slide in contact with the son; And a left and a right fixing member for inserting and fixing both ends of the bobbin and both ends of the mother, respectively, wherein the bobbin is a round bar made of aluminum having a diameter of 8 to 12 mm. It is another feature.

delete

In addition, the resistance wire has a constant diameter of 0.1 ~ 0.5mm and is wound to be in close contact with each other in a single layer, the son is having a resolution of 0.5mm or less, any one of the left and right fixing member is a third connection end Another feature of the slide type variable resistor according to the present invention is to form a conductive path in the mother, the son and the contact.

In addition, the left and right fixing member is characterized in that the slide type variable resistor according to the present invention that the transparent insulating protective cover that covers at least the resistor from among the resistor and the vernier caliper is further fastened.

In addition, the son is formed with a handle portion on the outside, the handle portion is covered with an insulating protective cover is another feature of the slide type variable resistor according to the present invention.

Meanwhile, the Wheatstone bridge test apparatus using the slide type variable resistor according to the present invention uses the slide type variable resistor, and both ends of the resistance wire are connected to the + and − poles of the power supply terminal, respectively, and the left and right sides are fixed. One of the members is characterized in that connected to the conductor connected to the galvanometer.

In addition, any one of both ends of the resistance wire and the left and right fixing members are connected to each other by a predetermined conductor on a PCB board having a thickness of 1 to 3 mm, and the PCB board is printed with a Wheatstone bridge circuit diagram on the front surface. It is mounted on the open housing, the left and right fixing member is fastened to one side of the housing is another feature of the Wheatstone bridge experimental apparatus using the slide-type variable resistor according to the present invention.

In addition, any one of both ends of the resistance line and the left and right fixing members are connected to each other by a predetermined conductor on a PCB board having a thickness of 1 to 3 mm, and the PCB board is printed with a Wheatstone bridge circuit diagram on the front surface. It is mounted on the open housing, the left and right fixing member is fastened to one side of the housing is another feature of the Wheatstone bridge experimental apparatus using the slide-type variable resistor according to the present invention.

On the other hand, the potentiometer experimental apparatus using a slide type variable resistor according to the present invention uses the slide type variable resistor, both ends of the resistance wire is connected to the + and-poles of the power supply terminal, respectively, of the left and right fixing members One is characterized in that connected to the conductor connected to the galvanometer.

In addition, any one of both ends of the resistance wire and the left and right fixing members are connected to each other by a predetermined conductor on a PCB board having a thickness of 1 to 3 mm, and the PCB board is printed with a potentiometer circuit diagram on its front surface and one side is open. It is mounted to the housing, and the left and right fixing member is fastened to one side of the housing is another feature of the potentiometer experiment apparatus using the slide-type variable resistor according to the present invention.

The slide type variable resistor according to the present invention basically solves the problem caused by heat generation by providing a resistor wound on a bobbin provided in a bobbin provided to dissipate heat, and a bobbin diameter and a thickness of the resistance wire. By selecting appropriately, the zero point of the galvanometer can be found more accurately with a coil-type slide type variable resistor, and the vernier caliper has the effect of easily and accurately measuring the length ratio of the resistor to the zero point of the galvanometer.

In addition, the Wheatstone bridge test apparatus and the potentiometer test apparatus according to the present invention have the effect that the zero point position of the galvanometer and the length ratio of the resistor can be obtained more accurately and easily by using the slide type variable resistor according to the present invention as it is. .

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

1 is an exploded perspective view showing a configuration of a slide type variable resistor according to the present invention, Figures 2 and 3 is a perspective view showing a state in which a protective cover or / and protective cover is further installed in the configuration of Figure 1, Figure 4 1 is a view illustrating a state in which the slide variable resistor according to FIG. 1 is mounted in the Wheatstone bridge experiment apparatus, and FIG. 5 is a view illustrating a state in which the slide variable resistor according to FIG. 1 is mounted in the potentiometer experiment apparatus, FIGS. 6 and FIG. 7 is a diagram illustrating an example of a PCB circuit board used in FIGS. 4 and 5, respectively.

First, as shown in FIG. 1, a slide type variable resistor according to the present invention basically has one resistance wire 16 coated with an insulating material 14 on a predetermined bobbin 12 wound around a coil 18. 1, the resistor 10 having the upper part of the coated film 14 peeled off in the longitudinal direction of the coil 18; A contactor 20 having one end sliding in contact with the resistor 10 from which the film 14 is peeled off; The other end of the contactor 20 is inserted into the sonar 30 mechanically and electrically connected to the predetermined opening 22 and the groove 31 by the bolt 24 and the inner groove 32 of the son, and the son 30. Vernier caliper consisting of a mother (40) is provided so that the sliding contact and sliding; And left and right fixing members 50 and 60 for inserting and fixing both ends of the bobbin 12 and both ends of the mother 40 into predetermined insertion grooves 52 and 54, respectively. do.

Here, the bobbin 12 is preferably made of a rod-shaped material having a high thermal conductivity such as aluminum, so that the thermal problem occurring in the resistance wire 16 of the coil 18 may be fundamentally solved.

At this time, the diameter of the bobbin 12 is preferably 8 to 12mm, more preferably 10mm. If the diameter is less than 8mm, the heat dissipation effect may be insignificant, but if it exceeds 12mm, there is a problem that wastes unnecessary bobbin material, and it becomes more difficult to continuously measure resistance, which is a disadvantage of the coil type slide potentiometer. There is this. This causes a problem that the zero point of the galvanometer cannot be found properly when applied to the Wheatstone bridge test device or the potentiometer test device.

That is, when the cross-sectional area of the resistance wire is A, the specific resistance of the resistance wire is p, and the radius of the coil is r, the resistance difference ΔR measured while the contactor 20 contacts the neighboring coil is as follows.

Equation 1 ΔR = 2πrρ / A

However, when the diameter of the bobbin 12 is increased, the coil radius r becomes large, resulting in a problem that the resistance difference ΔR between neighboring coils becomes large.

Accordingly, in order to maximize the heat dissipation effect of the bobbin 12 and not to increase the resistance difference ΔR between neighboring coils, the diameter of the bobbin 12 is preferably 8 to 12 mm.

In addition, the resistance wire 16 has a constant diameter within the range of 0.1 ~ 0.5mm, such as nichrome wire, as shown in Figure 1, it is preferable that the coil is densely wound so as to be in close contact with each other in a single layer.

The range of the preferred diameter of the resistance line 16 is determined in consideration of the error of the resistance difference ΔR between neighboring coils and the length ratio of the resistor 10.

That is, the resistance difference ΔR between neighboring coils is inversely proportional to the cross-sectional area A of the resistance line 16 in Equation 1, since the cross-sectional area A of the resistance line 16 is proportional to the square of the diameter of the resistance line 16, the diameter of the resistance line is 0.1 mm. If less than that, there is a problem that the resistance difference ΔR between neighboring coils rapidly increases, but if it exceeds 0.5mm, there is a problem that the error in the length ratio of the resistor 10 increases as much as the diameter of the resistance line 16 Will occur.

In the present specification, the length ratio of the resistor 10 refers to applying power to both ends of the resistance wire 16, and one or both ends of the power supply pass through predetermined circuit elements and galvanometers to the left and right fixing members 50 and 60. When the son 30 is moved to find the zero point of the galvanometer, the distance between the left and right sides of the resistor 10 (used in the Wheatstone bridge experiment) or When zero point is found at different points, it is the ratio of distance between one side and zero point (used in potentiometer experiment).

Therefore, it is preferable that the resolution of the son 30 (function of reading below the unit scale of the mother) is 0.5 mm or less, and any one of the left and right fixing members 50 and 60 is a third connection end. It is preferably used to form a conduction path (conduction path) in the mother (40), the son (30) and the contact (20).

In addition, the left and right fixing members 50 and 60 may cover only the resistor 10 as shown in FIG. 2, or cover the vernier calipers 30 and 40 as shown in FIG. 3. Transparent insulating protective cover 100, 200 may be further fastened.

By doing so, there is an advantage that an image or electrical contact due to the coil 18 contact can be avoided.

Further, the son 30 is further formed to the outside handle portion 34 to facilitate the son moving, as well as the handle portion 34, as shown in Figure 3, the insulating protective cover 36 is further covered It is desirable to make it possible to completely avoid electrical contact during use.

1 to 3, reference numerals 56, 110 and 210, which are not described, are through grooves, 57 are bolt fastening grooves, 58 are bolts for mounting the slide variable resistor to an external mechanism, and 59 are fastening protective covers. Is a bolt, 70 and 80 are conductive wires connected to both ends of the resistance wire 16, 90 is a conductive wire connected to the left fixing member 50, and 100 and 200 are protective covers.

On the other hand, the Wheatstone bridge experimental apparatus according to the present invention, as shown in Figure 4, using the slide-type variable resistor according to the embodiment, the both ends of the resistance wire 16 through the power supply line 70, 80, respectively It is connected to the + and-poles of the terminal, any one of the left and right fixing member 50, 60 is connected to the conductive wire 90 connected to the galvanometer 326.

By doing so, by utilizing the characteristics of the slide type variable resistor according to the above embodiment, the zero point of the galvanometer 326 can be accurately found by the movement of the son 30, and the length ratio of the resistor 10 can be easily obtained without error. Will be.

This facilitates the Wheatstone bridge experiment, it is possible to more accurately determine the unknown resistance Rx by the following equation (2).

Equation 2 Rx = Rk (l ₂ / l ₁ )

Here, Rk is the known resistance, l ₂ / l ₁ is the length ratio of the resistor 10, l ₁ is the length of the resistor (10) of the side of the same resistance (node) with the base resistor Rk, based on the zero point, l ₂ is The length of the resistor 10 on the side where the unknown resistor Rx and the node (node) are the same as the zero point is shown.

In the above embodiment, as shown in FIG. 4, more specifically, either one of both ends of the resistance wire 16 and the left and right fixing members 50 and 60 has a thickness of 1 to 3 mm on the PCB substrate 320. Each of the connection terminals 321, 323, and 325 is connected with predetermined conductive wires 70, 80, and 90, and the PCB substrate 320 has a Wheatstone bridge circuit diagram printed on the front surface and one surface of which is open. It is mounted to the housing 310, the left and right fixing members 50, 60 may be fastened to a predetermined fixing bolt 58 on one side of the housing.

At this time, when the thickness limit of the PCB 320 is less than 1mm, when the resistance or voltage is directly measured through the measurement terminals 327 on both ends of the circuit device, there is a problem in that the bending of the substrate occurs. If there is a problem that the manufacturing cost increases due to excessive material waste, it is preferable to set to 1-3mm.

In addition, in the present embodiment, the galvanometer 326 is a digital galvanometer, and at a position adjacent to the galvanometer, a buzzer 328 which emits a warning sound when a predetermined or more transient current flows in the galvanometer is provided, and the buzzer 328 has a beep sound. When flying, it is preferable to further include a switch 329 to block the branch connected to the galvanometer 326.

4, reference numeral 300 denotes a Wheatstone bridge test apparatus, 322 denotes an unknown resistance Rx selection button, and 324 denotes a known resistance Rk selection button.

6 shows only the PCB substrate 320 printed with the Wheatstone bridge circuit diagram.

By the configuration as described above, the Wheatstone bridge experimental apparatus utilizing the characteristics of the slide-type variable resistor according to the above embodiment can be easily assembled, and the mass production cost can be reduced.

On the other hand, the potentiometer experimental apparatus according to the present invention, as shown in Figure 5, using the slide-type variable resistor according to the embodiment, the both ends of the resistance wire 16 through the conductors 70, 80, respectively, of the power supply terminal It is connected to the + pole and the-pole, any one of the left and right fixing members 50, 60 is connected to the conductive wire 90 connected to the galvanometer 426.

By doing so, by utilizing the characteristics of the slide type variable resistor according to the above embodiment, the zero point of the galvanometer 426 can be accurately found by the movement of the son 30, and the length ratio of the resistor 10 can be easily obtained without error. Will be.

This facilitates the potentiometer experiment, it is possible to more accurately obtain the electromotive force Ex of the unknown battery by the following equation (3).

Equation 3 Ex = Es (l ₂ / l ₁ )

Here, Es is the electromotive force of the known battery, and l ₂ / l ₁ is the length ratio of the resistor 10.

And, l ₁ is the length of the resistor (10) between the zero point from the side connected to the + pole when the zero switch of the galvanometer 426 is found after connecting the switch 429 to the known battery Es, l ₂ Is When the changeover switch 429 is connected to the unknown battery Ek and the zero point of the galvanometer 426 is found, the length of the resistor 10 between the zero points is shown from the side where the resistance wire 16 is connected to the + pole.

5, more specifically, either one of both ends of the resistance wire 16 and the left and right fixing members 50 and 60 has a thickness of 1 to 3 mm on the PCB substrate 420. Each of the connection terminals 421, 423, 425 is connected to a predetermined conductive line 70, 80, 90, and the PCB substrate 420 has a potentiometer circuit diagram printed on the front surface thereof and an open side of the housing ( 410, the left and right fixing members 50 and 60 may be fastened to a predetermined fixing bolt 58 on one side of the housing.

At this time, when the thickness limit of the PCB 420 is less than 1mm, when the resistance or voltage is directly measured through the measurement terminals 427 at both ends of the circuit element, there is a problem in that the warpage of the substrate occurs. If there is a problem that the manufacturing cost increases due to excessive material waste, it is preferable to set to 1-3mm.

In FIG. 5, reference numeral 400 denotes a potentiometer experimental apparatus, 422 denotes a known battery or a standard battery, 424 denotes an unknown battery, 426 denotes a digital galvanometer, and 429 denotes a switching switch.

7 shows only the PCB substrate 420 on which the potentiometer circuit diagram is printed.

By the above configuration, it is possible to easily assemble the potentiometer experiment apparatus utilizing the characteristics of the slide-type variable resistor according to the above embodiment, and there is an advantage that the production cost can be reduced by mass production.

As described above, the preferred embodiments in which the core technical spirit of the present invention is implemented are described, but those skilled in the art can variously modify and implement the embodiments, and a description thereof will be omitted.

1 is an exploded perspective view showing the configuration of a slide type variable resistor according to the present invention.

2 and 3 are perspective views showing a state in which the protective cover or / and the protective cover is further installed in the configuration of FIG.

4 is a view illustrating a state in which the slide type variable resistor according to FIG. 1 is mounted in a Wheatstone bridge experiment apparatus.

5 is a view showing a state in which the slide type variable resistor according to Figure 1 is mounted on the potentiometer experiment apparatus.

6 and 7 illustrate an example of a PCB circuit board used in FIGS. 4 and 5, respectively.

<Explanation of symbols for the main parts of the drawings>

10: resistor 12: bobbin

14: Coated insulating material (film) 16: Resistance wire

18: coil 20: contactor

30: Son 40: Mother

50: left fixing member 60: right fixing member

70, 80, 90: conductor 100, 200: protective cover

300: Wheatstone Bridge Experiment 400: Potentiometer Experiment

Claims (9)

delete A resistor in which a single resistance wire coated with an insulating material on a predetermined bobbin is wound with a coil, and a part of the upper coated film is peeled off in the longitudinal direction of the coil; A contactor sliding in one end in contact with the peeled off resistor; A vernier caliper, the other end of which is inserted into a mechanically and electrically connected sonar and a mother inserted into the inner groove of the son and configured to slide in contact with the son; And It comprises a left and right fixing member for inserting and fixing the both ends of the bobbin and both ends of the mother, respectively, The bobbin is a slide type variable resistor, characterized in that the round bar of aluminum material having a diameter of 8 ~ 12mm. The method of claim 2, The resistance wire has a constant diameter of 0.1 ~ 0.5mm and is wound to be in close contact with each other in a single layer, The son has a resolution of less than 0.5mm, Any one of the left and right fixing members is used as a third connection end to form a conductive path in the mother, the son and the contact. The method of claim 3, wherein And the transparent insulating protective cover which covers at least the resistor among the resistor and the vernier caliper is further fastened to the left and right fixing members. The method of claim 4, wherein The son is formed with a handle on the outside, Sliding variable resistor, characterized in that the handle is covered with an insulating protective cover. Using a slide type variable resistor according to claim 3, Both ends of the resistance wire is connected to the + and-poles of the power terminal, respectively, Any one of the left and right fixing member is a Wheatstone bridge experimental apparatus using a slide type variable resistor, characterized in that connected to the conductor connected to the galvanometer. The method of claim 6, Both ends of the resistance wire and any one of the left and right fixing members are connected with predetermined wires on the PCB board having a thickness of 1 to 3 mm, respectively. The PCB board is mounted in a housing in which a Wheatstone bridge circuit diagram is printed on the front surface and one side is open. The Wheatstone bridge experiment apparatus using a slide type variable resistor, characterized in that the left and right fixing member is fastened to one side of the housing. Using a slide type variable resistor according to claim 3, Both ends of the resistance wire is connected to the + and-poles of the power terminal, respectively, Any one of the left and right fixing member is potentiometer experiment apparatus using a slide type variable resistor, characterized in that connected to the conducting wire connected to the galvanometer. The method of claim 8, Both ends of the resistance wire and any one of the left and right fixing members are connected with predetermined wires on the PCB board having a thickness of 1 to 3 mm, respectively. The PCB board is mounted on a housing in which a potentiometer circuit diagram is printed on the front surface and one side is open. Potentiometer experiment apparatus using a slide type variable resistor, characterized in that the left and right fixing member is fastened to one side of the housing.

Images