JP2012212554A - Battery pack structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily adjust a battery voltage according to a drive voltage of an electronic apparatus without preparation of a plurality of battery packs, a dummy battery, etc.SOLUTION: A battery pack 1 comprises plus-side and minus-side battery terminals 9a and 9b disposed on both ends of a plurality of insertion portions 4, to which a battery 3 can arbitrarily be inserted, for outputting the battery voltage to output terminals 2a and 2b. At at least one or more insertion portions 4, there are respectively provided battery detection means 5 for detecting the insertion or extraction of the battery 3 and switching means 6 for switching operation in cooperation with the detection of the battery detection means 5. The switching means 6 makes an electrically connected state between both ends of the insertion portion 4 when the battery insertion is not detected, and cuts off the connection between the battery terminals 9a and 9b on both ends of the insertion portion 4 when the battery insertion is detected.

Description

  The present invention relates to a structure of a battery pack attached to an electric device such as an electric tool.

  As the battery pack of the electric power tool, a battery pack in which the number of batteries connected in series is changed according to the output voltage is prepared. Therefore, it is often the case that the battery pack and the power tool main body are exchanged in accordance with the work, or all work is performed using the power tool and the battery pack capable of performing a large work. However, in the former case, since it is necessary to prepare a plurality of battery packs, there is a problem that costs increase. In the latter case, a power tool capable of performing a large work is used for all work, and particularly when performing light work, there is a problem that very delicate operations are required and skill is required. .

  Therefore, a conventional battery pack has an insertion / removal port for detachably inserting a storage battery, and a dummy battery having the same size as the storage battery is placed inside the casing of the battery pack in order to appropriately change the electromotive force of the plurality of storage batteries. There is known a battery pack in which the output voltage can be adjusted with one battery pack by inserting a dummy battery instead of a storage battery (see, for example, Patent Document 1).

JP-A-10-29172

  However, in the conventional example shown in Patent Document 1, it is necessary to always carry a dummy battery in order to adjust the voltage during work, and if the dummy battery is forgotten or lost, the battery pack Was not practical, such as being unable to use.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to facilitate the battery voltage according to the drive voltage of the electric device without preparing a plurality of battery packs or dummy batteries. It is an object of the present invention to provide a structure of a battery pack that can be adjusted.

  In order to solve the above-described problems, the present invention provides a battery pack that is detachably attached to an electric device, an output terminal for supplying a DC voltage to the electric device, and a plurality of batteries into which the battery is removably inserted. Each of the insertion parts has a positive and negative battery terminal for contacting the battery electrode and outputting a battery voltage to the output terminal. In addition, at least one or more of the insertion portions are respectively provided with battery detection means for detecting insertion / removal of a battery and switching means for performing a switch operation in conjunction with detection by the battery detection means. The switching means electrically connects the battery terminals at both ends of the insertion portion where battery insertion is not detected, and interrupts the connection between the battery terminals at both ends of the insertion portion where battery insertion is detected. And

  Further, the battery detecting means includes a displacement member that mechanically displaces when a battery is inserted into the insertion portion, and the switching means performs a switching operation in conjunction with the displacement of the displacement member. preferable.

  Moreover, it is preferable not to provide the battery detection means and the switching means in at least one of the plurality of insertion portions.

  The present invention can easily adjust the battery voltage of one battery pack according to the drive voltage of an electric device without preparing a plurality of battery packs or dummy batteries.

It is a wiring diagram which shows an example of the serial connection state of the battery in the inside of a battery pack provided with the battery detection means and switching means of one Embodiment of this invention. It is a perspective view of the battery case of a battery pack same as the above. It is a perspective view of the whole battery pack same as the above. It is a perspective view of the state which inserted the battery in each insertion part of a battery case same as the above. It is other embodiment of this invention, and shows an example at the time of comprising a battery detection means with a photo sensor, (a) is each explanatory drawing after inserting, before inserting a battery in an insertion part, (b). It is.

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

  FIG. 3 is an overall view of the battery pack 1. A positive output terminal 2 a for supplying a DC voltage to a rechargeable electric tool (not shown) and a negative output are provided in a housing 7 of the battery pack 1. Terminal 2b is provided. The housing 7 is divided into a battery case 7a and a case cover 7b, and the case cover 7b is fixed to the battery case 7a with screws. FIG. 4 is a perspective view of the battery case 7a with the case cover 7b removed. The battery 3 is a secondary battery such as a lithium ion battery.

  As shown in FIG. 2, the battery case 7a is provided with a plurality (four in this example) of cell spaces 4a to 4d in parallel as the insertion portion 4 for inserting the battery 3 (FIG. 4). Yes. At both ends of each of the cell spaces 4a to 4d, a positive battery terminal 9a that contacts the positive electrode 3a of the battery 3 and a negative battery terminal 9b that contacts the negative electrode 3b are provided.

  FIG. 1 shows an example of the wiring of the battery case 7a. The positive battery terminal 9a of the cell space 4a in the first column located at the start end of the cell space column is connected to the positive output terminal 2a. The negative battery terminal 9b of the cell space 4a is connected to the positive battery terminal 9a of the cell space 4b in the next row via a lead wire 8a. The minus battery terminal 9b of the cell space 4b is connected to the plus battery terminal 9a of the cell space 4c in the next row through a lead wire 8c. The minus battery terminal 9b of the cell space 4c is connected to the plus battery terminal 9a of the fourth cell space 4d located at the end of the cell space string via the lead wire 8d. The negative battery terminal 9b of the cell space 4d in the fourth row is connected to the negative output terminal 2b. A DC voltage is supplied to the power tool from the plus side and minus side output terminals 2a and 2b.

  Except for the cell space 4a in the first row, the cell spaces 4b to 4d in the second to fourth rows have a protrusion 5a constituting the battery detection means 5 and a mechanical switch 6a constituting the switching means 6, respectively. Is provided.

  Hereinafter, the protrusion 5a and the mechanical switch 6a provided in the cell space 4b in the second row in FIG. 1 will be described.

  A protrusion 5a (FIG. 2) is provided as a battery detection means 5 at the center of the bottom surface of the cell space 4b. The protrusion 5a constitutes a displacement member that is mechanically displaced. In this example, the protrusion 5a is always biased upward by a push-up spring (not shown). When the battery 3 is not inserted, the protrusion 5a is held at a position protruding upward. When the battery 3 is inserted, the protrusion 5a is pushed down against the spring force to switch the mechanical switch 6a from ON to OFF. do.

  The mechanical switch 6a is in a conductive state between the battery terminals 9a and 9b located at both ends of the cell space 4b in the ON state, and is in a disconnected state between the battery terminals 9a and 9b in the OFF state. The mechanical switch 6a of this example is connected to and separated from the contact 6b on the input side connected to the positive battery terminal 9a, the contact 6c on the output side connected to the negative battery terminal 9b, and both the contacts 6b and 6c. It consists of a movable contact piece 6d. This movable contact piece 6d moves up and down in conjunction with the up and down movement of the projection 5a. When the protrusion 5a is raised, the movable contact piece 6d comes into contact with both contact points 6b and 6c, and the battery terminals 9a and 9b are electrically connected. On the other hand, when the protrusion 5a is pushed down by the battery 3, the movable contact piece 6d is separated from both the contacts 6b and 6c, and the connection state between the battery terminals 9a and 9b is cut off.

  The protrusions 5a and mechanical switches 6a provided in the cell spaces 4c and 4d in the third and subsequent rows also have the same structure and function as the protrusions 5a and mechanical switches 6a provided in the second row of cell spaces 4b. The description is omitted.

  Next, a usage example will be described.

  As shown in FIG. 1, when the batteries 3 are inserted into the first to third cell spaces 4a to 4c, the protrusions 5a provided in the second and third cell spaces 4b and 4c are respectively provided. Pushed down. As a result, the second row and third row mechanical switches 6a are turned off. At this time, the protrusion 5a of the cell space 4d in the fourth row in which the battery 3 is not inserted does not descend, and the mechanical switch 6a in the fourth row is kept ON, so that the total voltage of the three battery voltages is output terminal The signal is output from between 2a and 2b. Further, when the battery 3 is inserted into the cell space 4d in the fourth row from the state of FIG. 1, the mechanical switch 6a in the fourth row is also turned off. At this time, the total voltage of the four battery voltages is output from between the output terminals 2a and 2b.

  On the other hand, when an arbitrary number of batteries 3 are taken out from any of the cell spaces 4b to 4d in the second to fourth rows, the protrusion 5a of the cell space from which the batteries 3 are taken out protrudes upward and the mechanical switch 6a is turned on. Can be switched to. As a result, the total voltage of the remaining battery voltages is output from between the output terminals 2a and 2b.

  Thus, in the battery pack 1 having the above-described configuration, the battery 3 is always inserted into the cell space 4a in the first row, and the other cell spaces 4b to 4d in the second to fourth rows are freely selected. Can be inserted. As a result, a total voltage of the inserted battery voltages can be output from the output terminals 2a and 2b and supplied to the electric tool, and different battery voltages can be obtained from one battery pack 1 by adjusting the number of batteries 3 to be inserted. Can be output. Therefore, since one battery pack 1 can handle a plurality of power tools having different driving voltages, it is not necessary for the user to purchase a battery pack 1 having a different output for each power tool as in the prior art, thereby reducing costs. Can be achieved. Moreover, it is not necessary to use a dummy battery as in the prior art, and since all the work can be handled by inserting and removing the necessary battery 3 in accordance with the work, the practicality is dramatically improved.

  In addition, when working with an electric tool, the electric tool is directed in various directions. At this time, the weight balance when held in the hand greatly affects workability. In the battery pack 1 of this example, since the battery 3 can be inserted by freely selecting the cell spaces 4b to 4d in the second to fourth rows, the insertion position of the battery 3 is determined in consideration of the weight balance and the center of gravity of the entire battery 3. It becomes possible to adjust, and workability can be improved.

  In this example, since the protrusion 5a that is mechanically displaced is used as the battery detection means 5, the battery detection means 5 can be easily realized with a simple structure. Further, a mechanical switch 6a driven by the protrusion 5a is used as the switching means 6. As a result, it is not necessary to perform a switch operation each time an unnecessary battery 3 is removed or a required battery 3 is added, and a power source for the switch operation is not necessary, thereby contributing to cost saving. Of course, not only the protrusion 5a but also a member that can be mechanically displaced when the battery 3 is pushed in can function as the battery detecting means 5.

  Further, in this example, the battery detection means 5 and the switching means 6 are not provided in the cell space 4a in the first row. In other words, the cell space 4a in the first row is a portion that secures the minimum driving voltage at which the electric device operates. In this portion, the protrusion 5a and the mechanical switch 6a can be omitted, so that further cost reduction can be realized. . If the battery 3 is not inserted into the cell space 4a in the first row, the battery pack 1 does not operate. Therefore, a fixing means for preventing the battery 3 from being removed is provided in the cell space 4a in the first row. You may do it.

  Depending on the electric tool used, the minimum voltage required for operation differs, and the number of cell spaces that do not include the protrusions 5a and the mechanical switches 6a may be adjusted accordingly. For example, when the required minimum voltage is high, the number of cell spaces not provided with the protrusions 5a and the mechanical switches 6a can be increased, and the cost can be further reduced.

  As another embodiment of the present invention, the battery detection means 5 may be constituted by a photo sensor, for example, and the switching means 6 may be constituted by an electrical switch made of a semiconductor element such as FET. A specific example of this example is shown in FIG. In FIG. 5, the light emitting unit 10 a and the light receiving unit 10 b of the photosensor 10 are arranged to face each other on opposite side walls of the cell space 4 b (or 4 c or 4 d). When the battery 3 is inserted into the cell space 4b, the light L to the light receiving unit 10b is blocked, so that the photosensor 10 optically detects the battery 3 and turns off the FET (not shown). Thereby, the detection operation and switching operation of the battery 3 similar to those in the above embodiment can be realized electronically.

  As still another embodiment of the battery detection means, a method of magnetically detecting insertion of the battery 3 using, for example, a Hall element may be used.

  Although the four cell spaces 4a to 4d are illustrated as the insertion portion 4 in the embodiment, the number of the cell spaces 4a to 4d can be appropriately changed in design.

  In the above embodiment, the cell space 4a is not provided with the battery detection means 5 and the switching means 6. However, the present invention is not limited to this, and the cell space 4a is also provided with the battery detection means 5 and the switching means 6. May be.

  In the above-described embodiment, a single battery is illustrated as the battery 3 to be inserted. However, the present invention is not limited to this, and the present invention can be similarly applied even when an assembled battery in which a plurality of batteries are connected in series or in parallel is used. is there.

DESCRIPTION OF SYMBOLS 1 Battery pack 2a, 2b Output terminal 3 Battery 3a Battery electrode 4 Insertion part 5 Battery detection means 5a Protrusion 6 Switching means 9a, 9b Battery terminal

Claims (3)

  A battery pack that is detachably attached to the electric device is provided with an output terminal for supplying a DC voltage to the electric device and a plurality of insertion portions into which the battery is removably inserted. The battery pack structure is provided with positive and negative battery terminals for contacting the battery electrodes and outputting the battery voltage to the output terminals at both ends, respectively, and at least one or more of the insertions Battery detecting means for detecting insertion / extraction of the battery and switching means for performing a switching operation in conjunction with detection by the battery detecting means, and the switching means is provided at both ends of the insertion portion where battery insertion is not detected. A battery pack structure characterized in that the battery terminals are electrically connected to each other and the connection between the battery terminals at both ends of the insertion portion where the battery insertion is detected is cut off.   The battery detecting means includes a displacement member that mechanically displaces when the battery is inserted into the insertion portion, and the switching means performs a switching operation in conjunction with the displacement of the displacement member. Item 6. A battery pack structure according to Item 1.   3. The battery pack structure according to claim 1, wherein the battery detection unit and the switching unit are not provided in at least one of the plurality of insertion units.

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