JP3789714B2 - Electrical appliance power plug connection structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention mainly relates to a structure for connecting a power plug to an electric appliance which is an electric shaver.
[0002]
[Prior art]
There are two types of electric appliances such as an electric razor, in which a plug metal directly connected to an AC 100V outlet is provided in the case, and a type in which a power plug is connected so as to be detachable. In the type in which the power plug is connected, it is not necessary to incorporate a power circuit in the electric appliance, and the entire structure can be simplified and the internal structure can be simplified. In addition, when a power plug connected to a power cord is used, the power plug can be used in a connected state.
[0003]
[Problems to be solved by the invention]
However, in the structure in which the power is connected by connecting the power plug, if there is water in the portion where the power plug is connected, the plug rod and the power terminal with a built-in power plug connected thereto may come into contact. Electric contact occurs when a leakage current flows between plug rods through water. When a leakage current flows between the plug rods, electric current is generated because the current melts the metal as metal ions. Electrical contact erodes the plug rod and power supply terminal from the surface and causes contact failure. This is because when the plug rod is eroded, it becomes thin, and when the power terminal is eroded, it becomes thin, and the power terminal cannot contact the plug rod with a sufficient contact pressure. Further, the deterioration of the surface condition also causes contact failure.
[0004]
Electrical contacts such as plug rods are particularly likely to occur in electrical appliances whose case is watertight. This is because a watertight electric appliance can be washed with water, so that when it is washed with water, water enters the insertion recess, and the accumulated water cannot be easily discharged.
[0005]
Electric contact due to leakage current can be prevented by reducing leakage current flowing between the plug rods. This is because the amount of erosion of the plug rod and the power supply terminal is proportional to the integrated value of the leakage current. In order to reduce the leakage current between the plug rods, it is necessary to make the insertion recesses into a shape in which water does not collect easily, or to increase the spacing between the plug rods.
[0006]
However, it is difficult for the structure in which the insertion recess is provided in the case and the power plug is inserted and connected to the case to make the insertion recess so that water does not accumulate. This is because it is necessary to close the bottom of the fitting recess with a watertight structure so that water does not enter the case. If a hole for draining is formed in the bottom, the water in the recessed portion can be drained. However, if a hole is formed here, the water in the recessed portion enters the case and adversely affects the internal electronic components.
[0007]
For this reason, in order to reduce the leakage current between the plug rods and the like, it is necessary to widen the interval between the plug rods disposed in the insertion recesses. There is a bad effect that cannot be made compact.
[0008]
The present invention was developed for the purpose of solving such drawbacks, and an important object of the present invention is to provide a power supply for an electric appliance that can effectively prevent electric contact due to a leakage current of water accumulated in a fitting recess. To provide a plug connection structure.
[0009]
[Means for Solving the Problems]
In the power plug connecting structure of the present invention, a fitting recess 2 for attaching / detaching the power plug 1 is provided in the case 3 of the electric appliance. The insertion recess 2 is provided with a plurality of plug rods 4 connected to the power plug 1. The power plug 1 is inserted into the insertion recess 2 and the power plug 1 is connected to the plug rod 4. The bottom surface of the insertion recess 2 is located between the adjacent plug rods 4 and is provided with an electrical contact prevention partition wall 5 protruding. The power plug 1 is provided with a notch 6 for viewing the anti-electric barrier 5. The electrical-prevention partition wall 5 is guided to the notch 6 and the power plug 1 is connected to the insertion recess 2. The contact prevention partition wall 5 has one side connected to the inner surface of the insertion recess 2 and the other end separated from the inner surface of the insertion recess 2 to provide a gap 7. Located in the gap 7, a valve hole 8 of a safety valve is opened at the bottom of the fitting recess 2.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. However, the embodiment shown below exemplifies the power supply plug connection structure of the electric appliance for embodying the technical idea of the present invention, and the present invention does not specify the connection structure of the power supply plug as follows. .
[0012]
Further, in this specification, in order to facilitate understanding of the scope of claims, the numbers corresponding to the members shown in the examples are referred to as “the scope of claims” and “the means for solving the problems”. It is added to the member shown by. However, the members shown in the claims are not limited to the members in the embodiments.
[0013]
Hereinafter, a specific example in which the electric appliance is an electric shaver will be described in detail. However, the present invention does not specify the electric appliance as an electric razor. For example, an electric appliance such as an electric toothbrush, an electric tool, a receiver, or the like can be used as an electric appliance that is connected to a power plug to supply electric power.
[0014]
The electric razor shown in FIG. 1 is provided with a fitting recess 2 for connecting a power plug to the bottom lid of the case 3. An enlarged perspective view of the insertion recess 2 is shown in FIG. 2, and a transverse sectional view and a longitudinal sectional view are shown in FIG. 3 and FIG. The insertion recess 2 shown in these figures has an opening that is long in the lateral direction. The insertion recess 2 is formed in a column shape extending in the insertion direction of the power plug 1 so that the power plug 1 shown in FIGS. 5 and 6 can be smoothly inserted. The power plug 1 is inserted and removed in a direction perpendicular to the surface of the bottom cover 3A that is the case 3. Therefore, the insertion recess 2 is formed in a column shape extending in a direction orthogonal to the surface of the bottom lid 3 </ b> A that is the case 3. The columnar shape is a shape in which the cross-sectional shapes of the surfaces orthogonal to the insertion direction of the power plug 1 are the same.
[0015]
2 to 4 are provided with guide ridges 9 for preventing reverse insertion of the power plug 1. The guide ridges 9 are provided so as to extend in the insertion direction of the power plug 1 and are integrally formed with the bottom lid 3A. The guide protrusion 9 in the figure is a mountain shape having a triangular cross-sectional shape, and is provided at the center of one inner surface. Furthermore, the insertion recessed part 2 of a figure is made into the shape which prevents the reverse insertion of the power plug 1 by making the curvature radius of a four corner part into another magnitude | size. In the insertion recess 2 in the figure, the curvature radii of the two corners close to the guide ridge 9 are reduced, and the curvature radii of the two corners far from the guide ridge 9 are increased.
[0016]
Furthermore, the insertion recess 2 in the figure is provided with a vertical groove 10 at a position facing the guide ridge 9, and is provided with a valve hole 8 communicating with the tip of the vertical groove 10 and penetrating the bottom lid 3A. The valve hole 8 is a safety valve with a thin film 11 attached to the inner surface of the case 3. The thin film 11 hermetically closes the valve hole 8, but when the internal pressure of the case 3 becomes high, the thin film 11 is broken and communicates with the valve hole 8 to the outside to discharge the gas in the case 3. A safety valve that opens the valve hole 8 in communication with the longitudinal groove 10 of the insertion recess 2 and closes the inner surface of the valve hole 8 with the thin film 11 causes the user to pierce the valve hole 8 with a needle or the like and damage the thin film 11. Can be effectively prevented.
[0017]
The fitting recess 2 is provided with an anti-electric partition wall 5 on the bottom in order to prevent leakage current between the plug rods due to the invading water. The insertion recess 2 which is long on the side of the figure is divided into two parts by providing an anti-electric barrier 5 at the center of the bottom. The electric-contact prevention partition wall 5 protrudes from the bottom surface of the insertion recess 2 and is integrally formed with the plastic bottom lid 3A. The anti-electric barrier 5 prevents a leakage current flowing through the adjacent plug rod 4. Accordingly, the anti-electric barrier 5 is formed of an insulating material. The case 3 of the appliance is molded with plastic almost without exception. Therefore, the anti-electric partition 5 is provided integrally with the plastic case.
[0018]
If the contact prevention partition wall 5 is too low, the leakage current cannot be effectively reduced. Therefore, the height of the electrical contact prevention partition wall 5 is preferably 1 to 5 mm, more preferably 2 to 4 mm. The contact prevention partition wall 5 is provided in communication with the peak portion of the guide protrusion 9. The anti-electric partition 5 acts as a guide for holding the power plug 1 inserted into the insertion recess 2 in a fixed position. The electrical contact barrier 5 is guided by the notch 6 of the power plug 1 shown in FIG. 7 and prevents the power plug 1 inserted into the insertion recess 2 from tilting. In order to prevent the inclination of the power plug 1, the thickness of the electric-contact preventing partition wall 5 is preferably 0.5 to 2 mm, more preferably about 1 mm, and sufficient strength.
[0019]
In order to open the valve hole 8 which is a safety valve, the insertion recess 2 shown in FIG. 3 connects one side of the electric-contact prevention partition wall 5 to the inner surface of the insertion recess 2 and the other end is separated from the inner surface of the insertion recess 2. A narrow gap 7 is provided in the longitudinal groove 10.
[0020]
The two plug rods 4 are fixed in parallel so as to be separated from both sides of the anti-electric barrier 5. In the figure, two plug rods 4 are fixed apart from each other in the longitudinal direction of the elongated insertion recess 2. Since the plug rod 4 supplies electric power to the electric razor, at least two plug rods are required. However, three or more plug rods can be provided. Three or more plug rods are connected to two or more plug rods in parallel to supply power, or are used as signal plug rods in addition to supplying power.
[0021]
In the illustrated electric razor, the plug rod 4 is fixed to the bottom lid 3A of the case 3 in a watertight structure in order to make the case 3 waterproof. As shown in FIG. 4, the plug rod 4 has a waterproof structure by pressing the O-ring 13 against the inner surface of the bottom cover 3 </ b> A with a flange 12. The plug rod 4 is fixed to a printed circuit board 14 disposed inside the case 3. The plug rod 4 fixed at a fixed position is at a position where the O-ring 13 is pressed by the flange 12, and penetrates the bottom lid 3A into the watertight structure.
[0022]
As shown in FIG. 5, the power plug 1 is provided with an insertion portion 1 </ b> A that can be smoothly inserted into and removed from the insertion recess 2 and that does not tilt when inserted into the insertion recess 2. The outer shape of the insertion portion 1A of the power plug is formed substantially equal to the inner shape of the insertion recess 2 so that it can be smoothly inserted and removed without tilting. The power plug 1 is connected to a power adapter 16 via a power cord 15 as shown in FIG.
[0023]
The power plug 1 shown in these drawings is connected to the insertion portion 1A, and the knob portion 1B and the bush portion 1C are integrally formed of plastic. The knob portion 1B is larger than the insertion portion 1A so that it can be easily grasped by hand. The bush portion 1C is deformed together with the power cord 15 to prevent the cord from being disconnected.
[0024]
As shown in FIG. 7, the power plug 1 is provided with a notch 6 for inserting the electric-contact preventing partition wall 5 provided in the insertion recess 2 at the distal end of the insertion portion 1 </ b> A. The notch 6 has a width that is equal to or slightly deeper than the height of the anti-electric barrier 5 and is substantially equal to the thickness of the anti-electric barrier 5. When the power plug 1 is inserted into the insertion recess 2, the anti-electric partition wall 5 is guided to the notch 6 of the insertion portion 1 </ b> A.
[0025]
The insertion portion 1A has a power supply terminal (not shown) connected to the plug rod 4 inserted therein. The power terminal is formed by processing a metal plate that can be elastically deformed into a cylindrical shape, and its inner diameter is slightly smaller than the outer diameter of the plug rod 4. When the plug rod 4 is inserted into this power supply terminal, the power supply terminal is elastically pressed against the surface of the plug rod 4 to ensure electrical connection. The insertion portion 1A has a connecting hole for inserting the plug rod 4 at the tip so that the plug rod 4 can be inserted into a built-in power supply terminal.
[0026]
Further, the power terminal is connected to a lead wire inside the knob portion 1B, and is connected to the power adapter 16 via this lead wire.
[0027]
When the power plug 1 is inserted into the insertion recess 2, the power adapter 16 is electrically connected to the plug rod 4 via the lead wire and the power terminal, and supplies power to the electric appliance.
[0028]
【The invention's effect】
The power supply plug connection structure of the electrical appliance according to the present invention effectively prevents electrical contact due to leakage current caused by water accumulated in the insertion recess provided in the case, and minimizes contact failure between the plug rod and the power supply plug. There is a feature that can be. The power plug connecting structure of the present invention is provided with an anti-electric partition wall that blocks leakage current between adjacent plug rods located at the bottom of the insertion recess, and the power plug is provided with this anti-electric partition wall. It is because the notch part to guide is provided. The insertion recess provided with the anti-electric partitioning wall separates the water that enters here, or lengthens a substantial distance between adjacent plug rods to prevent leakage current. For this reason, even if water intrudes into the insertion recess, the leakage current is reduced, and the plug rod and the power terminal due to the leakage current can be effectively prevented. This is extremely important for electric appliances that are used after being washed with water, such as an electric razor. This is because no matter how excellent the waterproof structure of the case is, if the plug rod and the power plug cause poor contact, they cannot be used for a long time without failure.
[0029]
Furthermore, the power supply plug connection structure for an electric appliance according to the present invention has an advantage that the power supply plug can be inserted into the insertion recess while guiding the power supply plug to a fixed position with an electrical contact prevention partition. For this reason, the power plug can be inserted into the insertion recess very smoothly, and the power terminal can be accurately guided to the plug rod.
[0030]
Furthermore, the power plug connection structure of the electric appliance according to the present invention effectively prevents the tilt of the power plug inserted in the insertion recess by guiding the electric-contact prevention partition provided in the insertion recess to the notch of the power plug. You can also This also has the feature that the power plug can be securely inserted into the insertion recess to reduce the contact failure between the plug rod and the power terminal, and the excessive deformation force can be applied to the plug rod and the power terminal. . Furthermore, there is a feature that can prevent an excessive deformation force from acting on the plug rod and the power terminal even when the power plug is inserted and removed.
[Brief description of the drawings]
FIG. 1 is a perspective view of an electric razor provided with a power plug connection structure according to an embodiment of the present invention. FIG. 2 is a perspective view of an insertion recess provided in the electric razor shown in FIG. Fig. 4 is a vertical cross-sectional view of the insertion recess shown in Fig. 2. Fig. 5 is a perspective view of a power plug inserted into the insertion recess. Fig. 6 is a perspective view of a power adapter connecting the power plug of Fig. 5. [Fig. 7] Front view of the power plug of FIG.
DESCRIPTION OF SYMBOLS 1 ... Power plug 1A ... Insertion part 1B ... Knob part 1C ... Bush part 2 ... Insertion recessed part 3 ... Case 3A ... Bottom cover 4 ... Plug rod 5 ... Electric contact prevention partition 6 ... Notch part 7 ... Air gap 8 ... Valve hole 9 ... Guide ridge 10 ... Vertical groove 11 ... Thin film 12 ... 鍔 13 ... O-ring 14 ... Printed circuit board 15 ... Power cord 16 ... Power adapter

Claims (1)

An insertion recess (2) for inserting an electric appliance so that the power plug (1) can be removed is provided in the case (3), and the insertion recess (2) includes a plurality of plugs connected to the power plug (1). The plug rod (4) is provided, and the power plug (1) is inserted into the insertion recess (2) so that the power plug (1) is connected to the plug rod (4). A power plug connection structure,
On the bottom of the insertion recess (2), an anti-electric partition wall (5) is provided so as to protrude between the adjacent plug rods (4), and the notch for inserting this anti-electric contact partition wall (5) (6) is provided on the power plug (1), and the anti-electric partition wall (5) is inserted into the notch (6) of the power plug (1), and the power plug (1) is inserted into the insertion recess (2). and so as to coupling, electric erosion preventing shroud (5) are linked to the inner surface of the fitting on one side recess (2), and provided with a gap (7) away from the other end inner surface of the fitting recess (2) A power plug connection structure for an electric appliance, which is located in the gap (7) and has a valve hole (8) of a safety valve opened at the bottom of the insertion recess (2) .

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