Electromagnetic tweezers

Abstract

To provide electromagnetic tweezers that prevent a handling error and have preferable operability.SOLUTION: An electromagnet 2 is provided in a distal end portion of tweezers 1 of a nipping type in which two panel materials face each other, the panel materials having root portions connected to each other. A pressure sensor 3 is provided in a portion of gripping the tweezers 1. When a pressure measured by the pressure sensor 3 exceeds a first threshold, A control part 5 turns on the electromagnet 2 when the pressure exceeds a first threshold, and turns off the electromagnet 2 when the pressure falls below the first threshold.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an electromagnetic gripper.

Background Art

[0002] A clamping-type gripper that clamps an object with two plate materials is used. However, the tip of the conventional gripper is likely to slip, and handling mistakes such as dropping of the object are likely to occur. When the tip of the gripper is made of rubber, there is a problem that foreign matter adheres to the object. On the other hand, an electromagnetic gripper in which an electromagnet is provided at the tip of one terminal has been proposed instead of the clamping-type gripper (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] If an electromagnet is simply provided at the tip of a clamping-type gripper, the user has to perform an ON / OFF switching operation of the electromagnet separately from the operation of the normal gripper, resulting in poor operability.

[0005] The present disclosure has been made to solve the above-described problems, and an object thereof is to obtain an electromagnetic gripper with good operability while preventing handling mistakes.

Means for Solving the Problems

[0006] The electromagnetic forceps according to the present disclosure is characterized in that it includes a clamping type forceps in which two plate materials with their root parts connected to each other face each other, an electromagnet provided at the tip of the forceps, a pressure sensor provided at the part for gripping the forceps, and a control unit that turns on the electromagnet when the pressure measured by the pressure sensor exceeds a first threshold value and turns off the electromagnet when the pressure is below the first threshold value.

Effect of the Invention

[0007] In the present disclosure, an electromagnet is provided at the tip of the forceps. Since the electromagnet adsorbs an object by magnetic force, it is possible to prevent handling mistakes when using the forceps. In addition, a pressure sensor is provided at the part for gripping the forceps, and when the pressure measured by the pressure sensor exceeds a first threshold value, the electromagnet is turned on, and when the pressure is below the first threshold value, the electromagnet is turned off. As a result, when the user performs the operation of normal forceps, the electromagnet is automatically turned on / off without the user's awareness, so the operability is good.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0009] The electromagnetic forceps according to the embodiment will be described with reference to the drawings. The same or corresponding components may be denoted by the same reference numerals, and the repeated description may be omitted.

[0010] Embodiment 1. Figure 1 is a diagram showing an electromagnetic clamp according to Embodiment 1. The clamping-type clamp 1 is formed by two plate members whose base portions are connected to each other and face each other. The material of the clamp 1 is a non-magnetic substance such as ceramic or stainless steel. When the user holds the portion between the tip and the base of the clamp 1 from the outside and applies force, the two tips of the clamp 1 approach each other to clamp an object.

[0011] Figure 2 is an enlarged cross-sectional view of the tip of the clamp surrounded by the dashed line in Figure 1. An electromagnet 2 is embedded inside the tip of the clamp 1. Figure 3 is a diagram showing the electromagnet. The electromagnet 2 is formed by spirally winding a coil such as a copper wire around a magnetic material such as iron. A magnetic force is generated by passing an electric current through the coil. The direction of the magnetic force is determined according to the direction in which the coil is wound or the direction in which the electric current flows.

[0012] When the clamp 1 clamps an object, the inside of the tip of the clamp 1 comes into contact with the object. On the other hand, the electromagnet 2 embedded inside the tip of the clamp 1 does not come into contact with the object. Therefore, it is possible to prevent the electromagnet 2 from coming into contact with the object and detaching from or being damaged by the clamp 1.

[0013] A pressure sensor 3 is provided at the portion where the user holds the clamp 1. The pressure sensor 3 is provided on at least one outer surface of the two plate members of the clamp 1. The index finger or thumb of the user comes into contact with the pressure sensor 3 to apply pressure. The pressure sensor 3 measures this pressure and outputs it as an electric signal.

[0014] A light-emitting element 4 such as an LED is provided on the outer side surface of the clamp 1 between the tip of the clamp 1 and the pressure sensor 3. Therefore, the user can see the light-emitting element 4 while holding the clamp 1. The control unit 5 controls the electromagnet 2 and the light-emitting element 4 according to the output of the pressure sensor 3. Note that the control unit 5 includes a power supply that supplies power to the electromagnet 2, the pressure sensor 3, and the light-emitting element 4 respectively, a switch that switches the power supply, and the like.

[0015] Figure 4 is a diagram showing the operation of the electromagnetic gripper according to Embodiment 1. The vertical axis represents the pressure measured by the pressure sensor 3. The horizontal axis represents the time when the user handles the gripper. Starting from the start time t0, the user gradually begins to apply force to the gripper 1. When the pressure measured by the pressure sensor 3 exceeds the first threshold value P1 at time t1, the control unit 5 passes a direct current through the electromagnet 2 to turn on the electromagnet 2. As a result, the electromagnet 2 attracts the object by magnetic force. Note that the magnetic force when the electromagnet 2 is on is constant and does not change according to the force applied by the user.

[0016] The user further increases the force, and the pressure measured by the pressure sensor 3 reaches the second threshold value P2 at time t2. The second threshold value P2 is larger than the first threshold value P1. If the user applies a force exceeding the second threshold value P2 to the gripper 1, there is a risk of damaging the object held by the gripper 1. Therefore, when the pressure measured by the pressure sensor 3 exceeds the second threshold value P2, the control unit 5 causes the light-emitting element 4 to emit light to give an alarm to the user. The pressure values of the first threshold value P1 and the second threshold value P2 can be obtained by prior tests.

[0017] For example, when the electromagnet 2 is on, the light-emitting element 4 may be lit green, and when the pressure exceeds the second threshold value P2 to give an alarm, the light-emitting element 4 may be lit red. By changing the color of the light emitted by the light-emitting element 4 during normal operation and during alarm in this way, the user can confirm both the ON / OFF of the electromagnet 2 and the presence or absence of an alarm.

[0018] The user checks the alarm and weakens the force, and applies a constant force to the gripper 1 from time t3 to perform a desired operation. The user begins to weaken the force from time t4 to release the object from the gripper 1. When the pressure measured by the pressure sensor 3 falls below the first threshold value P1, the control unit 5 turns off the electromagnet 2. As a result, the clamping force at the tip of the gripper 1 weakens, the attracting force of the electromagnet 2 disappears, and the object leaves the gripper 1 at time t5.

[0019] As described above, in this embodiment, an electromagnet 2 is provided at the tip of the tweezers 1. Since the electromagnet 2 attracts an object by magnetic force, it is possible to prevent handling mistakes when using the tweezers 1. Further, a pressure sensor 3 is provided at the portion where the tweezers 1 are gripped, and when the pressure measured by the pressure sensor 3 exceeds a first threshold value P1, the electromagnet 2 is turned on, and when the pressure falls below the first threshold value, the electromagnet 2 is turned off. As a result, when the user operates the normal tweezers 1, the electromagnet 2 is automatically turned on / off without the user's awareness, so the operability is good.

[0020] When the pressure measured by the pressure sensor 3 exceeds a second threshold value P2 that is larger than the first threshold value P1, the light emitting element 4 is caused to emit light to alert the user. Thereby, it is possible to prevent the user from applying too much force and damaging the object.

[0021] The electromagnet 2 only needs to be provided at at least one of the two tips of the tweezers 1, but it is preferably provided at both. The direction of the current flowing through the electromagnet 2 or the direction of the coil of the electromagnet 2 is adjusted so that the electromagnets 2 provided at the two tips attract each other when turned on. The handling performance is improved by the electromagnets 2 at the two tips attracting each other when turned on.

[0022] Note that it is also conceivable to provide the pressure sensor 3 at the tip of the tweezers 1. However, it is difficult to provide not only the electromagnet 2 but also the pressure sensor 3 at the thin tip of the tweezers 1. Further, when a cover is attached to the tip when storing the tweezers 1, if the tips come into contact with each other and pressure is applied at that time, the electromagnet 2 may malfunction. Furthermore, if the pressure sensor 3 at the tip comes into contact with the object, the pressure sensor 3 is likely to be damaged. By providing the pressure sensor 3 at the portion where the tweezers 1 are gripped, these problems can be avoided.

[0023] Embodiment 2. FIG. 5 is a diagram showing the operation of the electromagnetic clamp according to the second embodiment. In this embodiment, a third threshold value P3 that is greater than the first threshold value P1 and less than the second threshold value P2 is used. When the pressure measured by the pressure sensor 3 exceeds the third threshold value P3, the control unit 5 passes a direct current through the electromagnet 2. When the pressure measured by the pressure sensor 3 is between the first threshold value P1 and the third threshold value P3, the control unit 5 passes an alternating current through the electromagnet 2. Thereby, the control unit 5 passes an alternating current through the electromagnet 2 before switching the electromagnet 2 from ON to OFF.

[0024] When a direct current is passed through the electromagnet 2 when the object is grasped by the clamp 1, the object itself is magnetized. On the other hand, in this embodiment, an alternating current is passed through the electromagnet 2 in a state where the pressure just before the object leaves the clamp 1 is weakened. When an alternating current is passed through the electromagnet 2, the object is demagnetized in a short time. By automatically demagnetizing the object at the time of release in this way, unnecessary magnetism does not remain in the object.

[0025] In addition, by switching between direct current and alternating current according to the pressure measured by the pressure sensor 3, the control of demagnetization is simple. Even when the user starts applying force to the clamp 1 gradually, an alternating current flows through the electromagnet 2, but there is no particular problem.

[0026] As described above, the preferred embodiments have been described in detail. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope described in the claims. Hereinafter, aspects of the present disclosure will be summarized as supplementary notes. (Supplementary Note 1) A clamping-type clamp in which two plate materials whose base portions are connected to each other face each other, An electromagnet provided at the tip of the clamp, A pressure sensor provided at a portion for gripping the clamp, A control unit that turns on the electromagnet when the pressure measured by the pressure sensor exceeds a first threshold value and turns off the electromagnet when the pressure falls below the first threshold value. An electromagnetic clamp characterized by comprising: (Supplementary Note 2) The electromagnetic gripper according to appended claim 1, wherein the pressure sensor is provided on at least one outer surface of the two plate members of the gripper. (Appended claim 3) The electromagnetic gripper according to appended claim 1 or 2, wherein the electromagnet is embedded inside the tip of the gripper. (Appended claim 4) The electromagnet is provided on both of the two tips of the gripper, The electromagnetic gripper according to any one of appended claims 1 to 3, wherein the electromagnets provided on the two tips of the gripper attract each other when turned on. (Appended claim 5) The electromagnetic gripper further includes a light emitting element provided on the gripper, The electromagnetic gripper according to any one of appended claims 1 to 4, wherein when the pressure measured by the pressure sensor exceeds a second threshold value greater than the first threshold value, the control unit causes the light emitting element to emit light. (Appended claim 6) The electromagnetic gripper according to any one of appended claims 1 to 5, wherein the control unit passes an alternating current through the electromagnet before switching the electromagnet from ON to OFF. (Appended claim 7) When the pressure measured by the pressure sensor exceeds a third threshold value greater than the first threshold value, the control unit passes a direct current through the electromagnet, The electromagnetic gripper according to appended claim 6, wherein when the pressure measured by the pressure sensor is between the first threshold value and the third threshold value, the control unit passes an alternating current through the electromagnet.

Explanation of reference numerals

[0027] 1 Gripper, 2 Electromagnet, 3 Pressure sensor, 4 Light emitting element, 5 Control unit

Claims

1. A clamping type of tweezers in which two plate materials with their root parts connected to each other face each other, An electromagnet provided at the tip of the tweezers, A pressure sensor provided at the part where the tweezers are gripped, And a control unit that turns on the electromagnet when the pressure measured by the pressure sensor exceeds a first threshold value, and turns off the electromagnet when the pressure falls below the first threshold value. The electromagnetic tweezers are characterized by this.

2. The electromagnetic tweezers according to claim 1, wherein the pressure sensor is provided on at least one outer surface of the two plate materials of the tweezers.

3. The electromagnetic tweezers according to claim 1 or 2, wherein the electromagnet is embedded inside the tip of the tweezers.

4. The electromagnet is provided at both of the two tips of the tweezers, The electromagnetic tweezers according to claim 1 or 2, wherein the electromagnets provided at the two tips of the tweezers attract each other when turned on.

5. Further comprising a light emitting element provided on the tweezers, The electromagnetic tweezers according to claim 1 or 2, wherein the control unit causes the light emitting element to emit light when the pressure measured by the pressure sensor exceeds a second threshold value that is greater than the first threshold value.

6. The electromagnetic tweezers according to claim 1 or 2, wherein the control unit passes an alternating current through the electromagnet before switching the electromagnet from ON to OFF.

7. When the pressure measured by the pressure sensor exceeds a third threshold value that is greater than the first threshold value, the control unit passes a direct current through the electromagnet, The electromagnetic tweezers according to claim 6, wherein the control unit passes an alternating current through the electromagnet when the pressure measured by the pressure sensor is between the first threshold value and the third threshold value.

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