JPH0615951U - Ball plunger - Google Patents

Abstract

(57) [Summary] [Object] To provide a ball plunger capable of simplifying a manufacturing line by allowing a ball plunger that functions to position a carrier to have a function as a position sensor. A switch means is provided at a lower end portion of a moving piece 2 which moves up and down in cooperation with a vertical movement of a metal ball 1, and an electric signal as a position signal is generated by a vertical movement of the moving piece 2 which moves in cooperation with the metal ball 1. Let it out.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a ball plunger having a position sensor for deriving a position signal at the same time as positioning a carrier.

[0002]

[Prior art]

 Conventionally, the ball plunger 50 has been used as a positioning member in an automatic machine manufacturing line. As shown in FIG. 5, a conventional ball plunger 50 includes a metal ball 52, a part of which is exposed from the upper end of a tapered metal case 51, and a spring 53 which pushes up the metal ball 52 to the upper end side with a predetermined elastic force. It was mainly composed of

As shown in FIG. 6, for example, such a ball plunger 50 is fixed to a fixed base 100 so that the metal balls 52 are projected, and the carrier 101 is conveyed on the fixed base 100. A triangular recess 102 into which the metal ball 52 of the ball plunger 50 is fitted is formed on the back surface of the. In such an operation of the fixed base 100 and the carrier 101, when the carrier 101 is carried to a predetermined position on the fixed base 100, the recess 102 of the carrier 101 is fitted into the metal ball 52 of the ball plunger 10. Will be.

In a conventional use state, the ball plunger 50 only performs a positioning operation at a predetermined position, and the position signal indicating that the carrier 101 has reached the predetermined position is a carrier signal. This is performed by the position sensor 103 provided on the upper side of 101 and the position sensor tab 104 provided on the carrier 101. Based on this position signal, the workpiece (not shown) placed on the carrier 102 is subjected to predetermined processing, and at the same time as the processing is completed, the metal ball 52 fitted in the recess 102 of the carrier 101 can be withdrawn. Then, the carrier 101 is moved with sufficient force to complete the processing of the work.

[0005]

[Problems to be solved by the device]

 As described above, since the conventional ball plunger 50 is provided for positioning, even if the carrier 101 is stopped by the ball plunger 50 at a predetermined position, a position signal notifying that position is provided separately from the ball plunger 50. It is necessary to provide the position sensor 103 and the position sensor tab 104 for making the position sensor 103 recognize the position sensor 103, which causes a problem that a complicated control system circuit is required in constructing a manufacturing line for performing a predetermined processing on a work. was there.

The present invention has been devised in view of the above problems, and an object thereof is to allow a ball plunger, which acts on the positioning of a carrier, to also have a function as a position sensor, and a manufacturing line. It is to provide a ball plunger that can be simplified.

[0007]

[Means for Solving the Problems]

 According to the present invention, a metal ball that fluctuates up and down due to unevenness of a carrier, a fluctuating piece that fluctuates up and down in cooperation with a fluctuating movement of the metal ball, and a switch means that derives an electric signal by lowering the fluctuating piece. It is a ball plunger consisting of and.

As the switch means, a lower electrode member that comes into contact with each other when the moving piece moves downward is provided, and by bringing the moving piece and the lower electrode member into contact with each other, an electric signal as a position signal is provided. Is to be derived.

An oscillation coil is provided as the switching means, and a position signal whose oscillation frequency fluctuates is derived by a near-far variation between the oscillation coil and a magnetic member provided at the lower end of the variation piece. It is to let.

Further, the switching means includes a piezoelectric element that receives the mechanical stress of the variable piece, and derives an electric signal whose voltage changes according to the change of the variable piece.

[0011]

[Action]

 As described above, in the present invention, the position where the carrier should stop is regulated by fitting the metal ball into the recess formed on the back surface of the carrier. At this time, the position of the metal ball is changed by fitting the metal ball into the predetermined recess. Further, the fluctuating piece, which fluctuates in cooperation with the change of the metal ball, electrically or mechanically acts on the switch means, thereby electrically connecting the metal ball to the concave portion before and after the fitting. The position signal is derived from the change in the signal.

[0012] Therefore, since the ball plunger is for positioning and deriving the position signal, it is possible to eliminate the conventional position sensor and the like from the conventional manufacturing line, which simplifies the manufacturing line. To provide a possible ball plunger.

Here, by using an oscillation coil or a piezoelectric element as the switching means, it is not necessary to energize the variable piece and the like, so that restrictions on the mounting and use of the ball plunger are eliminated. It will be easy to handle.

[0014]

【Example】

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

FIG. 1 is a sectional view showing the structure of the ball plunger of the present invention.

In the figure, a ball plunger 10 includes a metal ball 1, a moving piece 2 that cooperates with the metal ball 1, a first spring 3 that applies an elastic force to the metal ball 1 via the moving piece 2. The lower electrode 4 which is in contact / non-contact with the moving piece 2, the lower base member 5 for fixing the lower electrode 4, the metal ball 1, the moving piece 2, the first spring 3, the lower electrode 4, the lower base member 5 It is composed of a metal case 6 for storing things such as.

The metal case 6 is made of a conductive material such as iron, and has a hollow portion 7 formed therein for accommodating the constituent members, and at least a part of the metal ball 1 is exposed at the tip (upper part in the figure). A hole 8 is formed. Further, the metal case 1, the variable piece 2, the first spring 3 and the like are housed inside the metal case 6, and a threading process for screwing the lower base member 5 into the opening on the lower side in the drawing is performed. It has been subjected.

Further, the outer periphery of the metal case 6 is threaded so that it can be easily fixed to a fixed base (not shown in the figure) at a predetermined position on the manufacturing line.

The metal ball 1 is made of a conductive material such as iron, and is arranged so as to partially project into the tip hole 8 of the metal case 6. That is, the diameter of the metal ball 1 is set larger than the opening diameter of the hole 8.

The variable piece 2 is formed by depositing a metal having a low contact resistance, for example, Cu or a metal having a low contact resistance on the surface of an insulating member, and extends from the receiving portion 9 of the metal ball 1 and the receiving portion 9. It is composed of the upper electrode portion 14.

The lower end side of the first spring 3 is fixed to or in contact with the metal case 6 or the lower pace member 5, and the upper end side is fixed to the receiving portion 9 of the variable piece 2. As a result, the elastic force of the spring 3 pushes up the metal ball 1 to the upper end side via the receiving portion 9 of the variable piece 2, and in a normal state, the metal ball 1 closes the opening hole 8. .

The lower electrode 4 is made of a metal having a low contact resistance, such as Cu, and has a contact portion 11 that contacts the lower end of the variable piece 2, and the lower end is joined to the lower base member 5. The output terminal 12 extends outward from the lower base member 5. The lower electrode 4 is joined to the lower base member 5 so as to slightly move up and down, and the initial state is maintained by the second spring 13.

The lower base member 5 is made of an insulating resin or the like, supports the lower electrode 4, and is fixed to the lower opening of the metal case 6.

In such a structure, the switch means is composed of the lower electrode 4 which is in contact with the variable piece 2, and a predetermined potential is applied between the metal case 2 and the output terminal 12.

In such a ball plunger 10, in the initial state in which the metal ball 1 closes the opening hole 8 of the metal case 6, the moving piece 2 is positioned on the upper end side by the first spring 3 together with the metal ball 1. There is. As a result, a constant gap is formed between the upper electrode portion 14 of the variable piece 2 and the contact portion 11 of the lower electrode 4, and the metal case 6 and the output terminal 12 are opened.

Such a ball plunger 1 is fixed, for example, as shown in FIG. 2, so that the metal ball 1 projects at a predetermined position of the fixed base 100. At this time, the wiring or the fixed base 100 itself is set to a predetermined potential, for example, the ground potential so that the metal case 6 can be energized. A triangular concave portion 102 into which the metal ball 1 of the ball plunger 10 is fitted is formed on the back surface of the carrier 101 that is conveyed while sliding on the fixed base 100.

Now, when the carrier 101 is placed on the metal ball 1 of the ball plunger 10, the metal ball 1 is pushed down by the weight of the carrier 101 and the like. As a result, the fluctuating piece 2 that moves together with the metal ball 1 also fluctuates toward the lower side, and the upper electrode portion 14 of the fluctuating piece 2 comes into contact with the contact portion 11 of the lower electrode 4. As a result, the lower electrode 4 and the output terminal 12 are electrically connected to each other through the metal case 6, the metal ball 1 and the changing piece 2, and an electric signal of a predetermined potential flows.

Next, when the carrier 101 reaches a predetermined position of the fixed base 100, the metal ball 1 is fitted into the recess 102 of the carrier 101. This is done by the elastic force of the first spring 3 that pushes up the metal ball 1. When the fluctuating piece 2 that moves together with the metal ball 1 fluctuates to the upper side, a gap is created between the fluctuating piece 2 and the contact portion 11 of the lower electrode 4, and the electrically open state.

That is, by detecting the change in the energized state between the metal case 6 and the output terminal 12 after the carrier 101 is placed on the fixed base 100, the change in the energized state to the non-energized state is detected. The signal can be derived.

FIG. 3 is a sectional view showing the structure of a ball plunger 20 according to another embodiment of the present invention.

In this embodiment, the oscillation coil 22 is used as the switching means. Structurally, a magnetic material 21 is provided at the lower end of the variable piece 2, and the oscillation coil 22 is used instead of the lower electrode 4 described above. Both windings of the oscillating coil 22 are connected to output terminals 23 and 24. Although not shown, the oscillation coil 22 is, for example, an L component of the LC resonance circuit. Although the moving piece 2 cooperates with the metal ball 1, a predetermined gap is formed with the core of the vibration coil 22 even when the magnetic material 21 is at the lowest point.

In operation, the distance between the oscillation coil 22 and the magnetic member 21 changes when the moving piece 2 moves up and down due to the relationship between the recess 103 of the carrier 102 and the metal ball 1. As a result, the resonance frequency of the LC resonance circuit changes. The position signal can be derived based on the change in the resonance frequency.

FIG. 4 is a sectional view showing the structure of still another ball plunger 30 of the present invention.

In this embodiment, a strain gauge 31 such as a piezoelectric ceramic is used as the switching means. Structurally, the lower electrode 4 of the first embodiment is eliminated and the strain gauge 31 is fixed on the lower base member 5. The output electrodes 31a and 31b of the strain gauge 31 are connected to the output terminals 32a and 32b of the lower base member 5.

In operation, due to the relationship between the recess 103 of the carrier 102 and the metal ball 1, when the moving piece 2 moves up and down, the pressurization state of the strain gauge 31 changes, which causes an output. The potential between the terminals 31a and 31b fluctuates. The position signal can be derived based on this change in potential.

In the embodiment shown in FIGS. 3 and 4, since it is not necessary to apply a potential to the cases 26 and 36, it is not necessary to use a case made of a metal member, and the fixed base 101 is also provided with a conducting means. Since there is no need to do so, restrictions on the intended use of the production line will be resolved.

For the positioning of the above-mentioned ball plunger, the metal ball 1 is pushed up into the recess 103 by the elastic force of the first spring 3 so that the carrier 102 is mechanically held. However, for example, the means for mechanically holding the carrier 102 may be performed by another means, and a positioning signal may be given to the holding means to operate the holding means. For example, when the carrier 102 is carried by a drive source such as a motor, the drive source may be stopped based on the position signal from the ball plunger.

Further, instead of placing the work on the carrier 101, a recess may be formed directly on the back surface of the work. For example, as a work, a substrate for multi-cavity use may be used, and the groove may be formed as a divided groove.

[0039]

[Effect of device]

 As described above, according to the ball plunger of the present invention, it is possible to derive a positioning signal, and as in the conventional case, it has both the function of positioning the ball plunger and the function of the position sensor. The construction of the manufacturing line during the manufacturing process becomes extremely easy.

[Brief description of drawings]

FIG. 1 is a sectional view showing the structure of a ball plunger of the present invention.

FIG. 2 is a schematic view for explaining a usage state of the ball plunger of the present invention.

FIG. 3 is a sectional view showing a structure of a ball plunger according to another embodiment of the present invention.

FIG. 4 is a sectional view showing the structure of still another ball plunger of the present invention.

FIG. 5 is a cross-sectional view showing the structure of a conventional ball plunger.

FIG. 6 is a schematic diagram for explaining a usage state of a conventional ball plunger.

[Explanation of symbols]

 10, 20, 30 ... Ball plunger 1 ... Metal ball 2 ... Fluctuating piece 3 ... Spring 4 ... Lower electrode 5 ... Lower base member 6 ... Metal case 21 ... Magnetic material 22 ... Oscillation coil 12, 23, 24, 31a, 31b ... Output terminal 31 ... Strain gauge 26, 36 ... Case

Claims (4)

[Scope of utility model registration request] 1. A metal ball that fluctuates up and down due to unevenness formed on a sliding surface of a carrier, a fluctuating piece that fluctuates up and down in cooperation with a fluctuating movement of the metal ball, and an electric signal when the fluctuating piece descends. And a switch means for deriving the ball plunger. 2. The ball plunger according to claim 1, wherein the variable piece is made of a conductive member, and the switch means is provided with a lower electrode that comes into contact with the movable piece when the variable piece descends. 3. A magnetic member is provided at the lower end of the variable piece, and the switching means is provided with a coil whose frequency fluctuates due to the fluctuation of the magnetic member. Item 1. A ball plunger according to item 1. 4. The ball plunger according to claim 1, wherein the switching means includes a piezoelectric element that receives the mechanical stress of the variable piece.