JPH0634691Y2 - Measuring instrument terminal device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a measuring instrument for measuring the electrical characteristics of an object to be measured, and more specifically, in a measuring instrument having a plurality of input / output terminals, these terminals are used. Of these, the present invention relates to a terminal device for a measuring instrument, in which only desired terminals can be connected and the remaining terminals cannot be connected.

[Technical background of the invention] A measuring instrument for measuring the electrical characteristics of an object to be measured, such as a clamp-type ammeter, is a pair of magnetic cores and a core-shaped winding coil that can be opened and closed in a live circuit to be measured. This clamp sensor is packaged in a live circuit to be measured, which is composed of a magnetic-electric converter, etc., and the magnetic flux induced in the magnetic core is converted into an electric signal via the magnetic-electric converter and combined with the clamp sensor. It is displayed as an alternating current and a direct current value on a display unit or the like on the main body to be combined. On the other hand, by using the Hall element as the magnetoelectric conversion element, not only the AC and DC currents can be measured but also the power can be measured by the multiplication function,
Clamp-type ammeters using Hall elements have become widespread.

7 and 8 show an example of a conventional clamp type ammeter.

Of these, FIG. 7 shows the clamp type ammeter in which the current detection unit 101 and the display unit 102 are separated and connected to each other via a cord 105.
A voltage input terminal 103 and an output terminal 104 are provided respectively.

In addition, the clamp type ammeter shown in Fig. 8 is designed to be a handy type suitable for the measurement work in the field,
It is configured by integrating 101 and the display unit 102.

[Problems to be Solved by the Invention] With respect to the clamp type ammeter as described above, not only the current measurement is performed in a live line state in which the electric path is not cut, but also the output terminal is used to measure the current. There is a strong demand for recording and observing the output waveform at the same time.
Furthermore, as a general-purpose type clamp-type current generator, there is also a strong demand for use as a voltage measurement device.

In response to such a demand, in the case of the separate type clamp ammeter shown in FIG. 7, the circuit between the voltage input terminal 103 on the input side and the output terminal 104 on the output side is completely insulated. If the measured voltage is floating or if the AC ungrounded side is connected to the negative terminal of the voltage input terminal, a voltage close to the measured voltage may appear at the output terminal. There was a risk of causing an electric shock accident or a short circuit accident. Therefore, the shapes of the jacks of the input terminals are made different from each other to prevent the insertion, and at the time of voltage measurement, caution is required to confirm that the output terminal side is not connected.

On the other hand, in the case of an integrated type hand-held clamp type ammeter as shown in Fig. 8, the space for the circuit board is narrowed because the whole shape needs to be made compact, and the product price is also better. Due to circumstances such as the need to be inexpensive, the number of parts to be equipped was limited by itself, and it was difficult to obtain insulation on the circuit. For this reason, the handheld clamp type ammeter has no choice but to deal with it by taking a product form in which the voltage input terminal 103 and the output terminal 104 do not coexist from the viewpoint of safety measures. Even if the current detecting unit having the structure is used, there is an inconvenience and an uneconomical situation that two models, one having the voltage input terminal 103 and one having the output terminal 104 must be used properly.

[Object of the Invention] The object of the present invention is to prevent the accidents described above from occurring by making it possible to connect only desired terminals and not connect the remaining terminals in a measuring instrument having a plurality of terminals. An object of the present invention is to provide a terminal device for a measuring instrument having a simple structure.

[Means for Solving the Problems] In order to achieve the above object, the present invention has the following configuration.

That is, the present invention is a measuring instrument for measuring electrical characteristics of a device under test, which comprises a plurality of terminals for input / output connection on one surface of a housing, the measuring instrument being formed on one surface of the housing and having the terminals inside thereof. Of the recess for accommodating and the terminal for input / output connection, at least a part of the terminal for either input connection or output connection is covered, and the terminal on the other side is used as an alternative. It is characterized in that it has a lid slidably mounted on the recess so as to be freely exposed.

[Embodiment] Hereinafter, one embodiment of the present invention will be described in detail by taking a case where it is applied to a clamp type ammeter as an example. In FIG. 1, a pair of semi-annular ring-shaped members that can be opened and closed are combined. A current detection unit 1 including a magnetic core (not shown) and a core holder 3 including a handle 2 for opening and closing the pair of magnetic cores, and a current value detected by the current detection unit 1 are displayed. There is shown a clamp type ammeter as an example which is constituted by a case main body portion 4 as a housing including a display portion 8 and the like.

FIG. 2 shows the structure of the case main body 4 as a housing in this clamp type ammeter, and includes a battery B, a display unit 8 which is preferably a digital type, and if necessary, an analog type, and a measurement circuit. A holder portion 5 accommodating the holder portion 5, a panel portion 6 provided on the upper surface side of the holder portion 5 and provided with a window portion 26 for exposing the display portion 8, and the lower surface side of the holder portion 5. The back case portion 7 is attached to the back case portion 7 and the whole is integrally assembled by screwing a set screw (not shown).

The holder portion 5 that constitutes the case body portion 4 as such a housing extends in the appropriate direction, preferably on either the left or right side end surface 9 of the holder portion 5 as shown in the drawing. A substantially rectangular recess 10 is formed, and an insertion port 28 for a plurality of terminals, for example, a two-terminal type voltage input terminal jack 11 and a concentric type output terminal jack 12, is arranged at one end of the recess 10. In the recess 10, a lid 13 slidably attached to the holder portion 5 is covered. In this case, on the side end surface 9 of the holder portion 5 and on the side close to the side edge portion of the back case portion 7, one side edge portion 19 in the longitudinal direction of the lid body 13 is slidably movable. A guide groove (14) for inserting and supporting is formed so as to make the surface height of the recess (10) coincide with that of the recess (10). In addition, at the one end in the sliding direction of the lid body 13 that is in sliding contact with the recess 10, a step that can prevent the movement of the lid body 13
15, the lid 13 can be slid at the other end to accommodate the lid 13 to a predetermined length, and an opening 17 is also provided on the side of the side edge 23 of the adjacent panel portions 6. Storage parts 16 are provided respectively.

Regarding the relationship between the voltage input terminal jack 11 and the output terminal jack 12 and the lid 13 provided on the upper surface thereof, as shown in FIG. A predetermined length, that is, the knob portion 18 erected on the lid body 13 functions as a positioning piece, and when the length reaching the position where this is blocked by the storage portion 16 and the movement is stopped is stored, The output terminal jack 12 must be covered so that only the voltage input terminal jack 11 can be freely used for its alternative use. In addition, as shown in FIG. 3 (b), the lid body is inserted through the step portion 15 of the recess 10.
When the switch 13 is stopped, the voltage input terminal jack 11 should be covered so that only the output terminal jack 12 can be freely used for its alternative use.

On the other hand, the other side edge portion 20 in the length direction of the lid body 13 is provided with a step portion 21 on the side edge portion 23 of the panel portion 6 as shown in FIG. It is possible to form a space between the holder part 5 and the step part 21 when the cover part 13 is attached to the guide part 14, and the space is formed between the holder part 5 and the step part 21. Similar to the relationship with the one side edge portion 19, it can be slidably supported by loose insertion.

5 and 6 are similar to those of the structure shown in FIG. 3, while the amount of movement of the lid 13 to be slid is small enough not to require the storage portion 16. It shows another embodiment in which a required terminal among the terminals, for example, either one of the voltage input terminal jack 11 and the output terminal jack 12 can be exclusively used. That is, when the voltage input terminal jack 11 and the output terminal jack 12 of the recess 10 are arranged in a row in the sliding direction of the lid body 13, they are slid on the upper surfaces of these terminal jacks 11 and 12. 10 shows another embodiment of the structure of the lid 13 that is movably covered. Of these, Figures 5 (a) and (b)
In consideration of the positional relationship between the voltage input terminal jack 11 and the output terminal jack 12, the lid 13 in FIG.
However, when sliding it in the upward direction, when the output terminal jack 12 is provided with two openings 24, 25 having the same shape at positions where each of the alternative uses can be freely expressed. Here is an example: Further, the lid 13 in FIGS. 6 (a) and 6 (b) shows a modified example of FIG. 5 in which the amount of movement at the time of sliding can be further reduced, and is shown in the downward direction in FIG. When the lid 13 is slid, all of the voltage input terminal jacks 11 and part of the output terminal jacks 12 are slid, and when slid in the upper direction, all of the output terminal jacks 12 and one of the voltage input terminal jacks 11 are slid. Due to the positional relationship of each part,
An example is shown in which the upper opening 24 has an oval shape and the lower opening 25 has a circular shape.

In the case of the embodiment shown in FIGS. 5 and 6 described above, the amount of movement of the lid body 13 during sliding can be reduced, so that the holder portion 5 that constitutes the case body portion 4 as a housing. In addition to the left or right side end surface 9 in FIG.
An insertion port for the output terminal jack 11 and the insertion port for the output terminal jack 12 is arranged, and a lid 13 can be slidably provided on the upper surface thereof. Moreover, as a result of reducing the movement amount of the lid 13 during sliding,
The storage portion 16 for storing the lid body 13 as in the embodiment shown in FIG. 2 is not necessary, so that it is not necessary for the knob portion 18 to have a function as a positioning piece in relation to the storage portion 16. , That much more design freedom can be achieved.

In the figure, reference numeral 27 is a set screw, 30 is a circuit board, and 31 is a circuit board.
Indicates a terminal fitting and 32 indicates a lead wire.

Next, regarding the terminal device of the measuring instrument configured in this way,
The operation will be described by taking the illustrated clamp type ammeter as an example.

The clamp type ammeter including the current detector 1 and the case body 4 can measure the current by enclosing and closing the core holder portion 3 in the live circuit to be measured. The measured current value is displayed on the display section 8 of the main body section 4.

When measuring the voltage, the side end surface 9 of the holder 5 is
Cover that is slidably covered on the upper surfaces of the voltage input terminal jack 11 and the output terminal jack 12 that are co-located
As shown in FIG. 3 (a), 13 is pushed up through the knob portion 18, and a part of it is stored in the storage portion 16 so that only the voltage input terminal jack 11 can be selectively used. Then, a plug of an external cord may be inserted into this and connected thereto. Therefore, while the voltage input terminal jack 11 is being used, the output terminal jack 12 is covered with the lid 13 and cannot be used, and erroneous connection can be reliably prevented. At this time, output terminal jack
When the terminal structure and the arrangement relationship on the output terminal jack 12 side are changed in relation to 12, it is possible to prevent erroneous connection more effectively.

When the output is to be recorded on an external recorder or the output waveform is to be observed by an external device at the same time as the current measurement, the lid 13 is recessed as shown in FIG. 3 (b).
By pulling the voltage input terminal jack 11 down to the position where it abuts the stepped portion 15 of the cover 10, the voltage input terminal jack 11 is covered by the lid 13, and only the output terminal jack 12 can be freely used for its alternative use. This can be done by connecting the plug of the predetermined cord to the terminal jack 12 without error. Therefore, even in this case, erroneous connection can be reliably prevented.

On the other hand, as shown in FIG. 5, when two openings 24 and 25 having the same shape are previously formed in the lid body 13, the lid body 13
By pulling down as shown in FIG. 5 (a), only the voltage input terminal jack 11 can be freely exposed for alternative use. Further, by pushing up the lid 13 as shown in FIG. 5 (b), only the output terminal jack 12 can be selectively exposed through the shared opening 24.

Further, according to the embodiment shown in FIG. 6, since the shared opening 24 is formed in an oval shape, the lid 13 is formed.
6 is pulled down as shown in FIG. 6 (a), the output terminal jack 12 is partially exposed through the opening 24, but is exclusively exposed so that only the voltage input terminal jack 11 can be used. Can be made. When the lid 13 is pushed up as shown in FIG. 6 (b), the voltage input terminal jack 11 is partially exposed through the shared opening 24, but only the output terminal jack 12 is used. You can express it exclusively as you can.

Further, even when the back case portion 7 may be removed from the holder portion 5 of the case main body portion 4 serving as a housing, for example, to replace the battery B, the one side edge portion 19 of the lid body 13 has the holder portion 5. Groove formed on the side end surface 9 of the
Since it can still be retained via 14, it can be effectively prevented from falling off.

In the present invention, an example applied to a clamp type ammeter has been described, but it goes without saying that it can be used as a terminal device of various other measuring instruments.

[Advantages of the Invention] As described above, according to the present invention, the plurality of input / output connection terminals co-located in the case body are slidably covered on the upper surface thereof. By going through
Only one of the desired terminals for input connection or output connection can be selectively used, so that incorrect connection can be eliminated and insulation for voltage input on the circuit can be eliminated. It is possible to eliminate the need to take it, reduce the number of parts to be equipped, and reduce the cost and the size. Moreover, not only is it possible to record and monitor the output waveform via an external device with only one model, but it is also possible to perform voltage measurement and, in addition, to prevent electric shock or short circuit accidents. It can be effectively prevented and used.

[Brief description of drawings]

FIG. 1 is a front view showing the whole of one embodiment of the present invention applied to a clamp type ammeter, FIG. 2 is an exploded perspective view of a main part thereof, and FIGS. 3 (a) and 3 (b) are second views. Explanatory drawing which shows the sliding state of the lid body about the Example shown in FIG. 4, FIG. 4 is an enlarged sectional view along line AA in FIG. 3 (b), FIG. 5 (a),
(B) and FIGS. 6 (a) and (b) are explanatory views showing the sliding state of the lid body as another embodiment, and FIGS. 7 and 8 are the whole of the conventional clamp type ammeter. FIG. 1 ... Current detection part, 2 ... grip, 3 ... core holder, 4 ... case body part, 5 ... holder part, 6 ... panel part, 7 ... back case part, 8 ... display part, 9 ...... Side end face, 10 ... Recess, 11 ... Voltage input terminal jack, 12 ... Output terminal jack, 13 ... Lid, 14 ... Guide groove, 15 ... Step section, 16 ... Storage section, 17 …… Opening, 18 …… Knob, 19 …… One side edge, 20 …… Other side edge, 21 …… Step section, 22 …… Bottom end surface, 23 …… Side edge, 24,25 …… Opening, 26 …… Window, 27 …… Set screw, 28 …… Insertion port, B …… Battery

Claims (3)

[Scope of utility model registration request] 1. A measuring instrument for measuring electrical characteristics of a device under test, comprising a plurality of terminals for input / output connection on one surface of a housing, the measuring instrument being formed on one surface of the housing and accommodating the terminals therein. Of the recess and the terminal for input / output connection, at least a part of the terminal on one side for input connection or output connection is covered, and the terminal on the other side can be freely selected or used. And a lid body slidably mounted on the recess so as to be exposed. 2. In the claim 1 of the utility model registration claim,
On one surface of the housing at one end in the sliding direction of the lid,
A measuring device for a measuring instrument, wherein a storage section for storing the lid is formed so that the lid covers only one of the terminals. 3. A utility model registration claim as set forth in claim 1.
The measuring device for a measuring instrument, wherein the lid is provided with an opening that is aligned with only one of the terminals depending on its sliding direction.