JP2528607B2 - Rotary electrical connector and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary electric connector which reduces the number of parts and the number of manufacturing steps.

[0002]

2. Description of the Related Art A cord reel incorporated in an electric vacuum cleaner or the like allows relative rotation between a rotating conductor and a stationary conductor so that the electric cord can be freely pulled out from the rotating reel. A rotary electric connector capable of achieving electrical continuity is required. This type of rotary electrical connector has both the rotating and stationary sliding members molded into a flat ring in addition to the old model that combines a slip ring and a brush that makes sliding contact with it, and insulates these flat rings. A new type in which multiple plates are alternately laminated via a ring has appeared, and the rotary electric connector disclosed in Japanese Utility Model Publication No. 63-9115 "slip ring device for reels" is a typical example. May be.

The rotary electric connector disclosed in the above publication has a flat plate-shaped stationary ring made of an electric conductor, which has a spline shaft made of an electric insulator having a spline groove, and internal teeth fitted to the spline groove. A flat plate-shaped rotating ring made of a conductor having no teeth is externally fitted to a plurality of sets (for example, three sets for three-phase alternating current) via an electrically insulating ring, and a member fitted to the spline shaft is attached to the axis of the spline shaft. A coil spring is provided as a means for pressing in the direction, and a pressurizing ring with a pedestal and a reel drum hole are provided as means for restraining the rotation of the flat plate-shaped rotating ring on the cord reel. A flat plate-shaped rotating ring made of a conductive material having no teeth and a flat plate-shaped ring made of a conductive material having internal teeth that are stationary together with the spline shaft are electrically connected to each pair.

[0004]

In the conventional rotary electric connector described above, the electric insulating ring for insulating the pair of the flat plate-shaped stationary ring and the flat plate-shaped rotary ring between each pair is composed of independent parts. However, there were the following drawbacks.

For example, when applied to a cord reel of a three-core cord, two electrical insulating rings are required to insulate between three pairs of pairs, and even when assembled, these two independent electrical insulating rings are used. It is necessary to insert the ring between the adjacent conductive contact pairs.

For this reason, although only two sheets are required, two electrical insulating rings are required in addition to the flat plate-shaped stationary ring and the flat plate-shaped rotating ring, each of which is three in number. Increasing the number of points is unavoidable, and the time and effort required to insert and insert the electrical insulating ring have also been a cause of increasing the total number of manufacturing steps.

Further, not only the rotary type electrical connector,
In general, an electrical connector of a type that achieves electrical conduction through a sliding contact portion is likely to cause adverse effects such as insulation failure due to foreign matter being caught or an increase in lubrication load on the sliding contact portion as the sliding contact portion and the sliding contact area increase. Is. However, the conventional rotary electric connector has a sliding contact surface between the flat rotary ring and the electric insulating ring and between the electric insulating ring and the flat stationary ring, that is, both surfaces of the electric insulating ring are sliding surfaces. Since the sliding contact area was large, the probability of foreign matter entering the sliding contact surface was high.

Therefore, in order to eliminate the risk of dielectric breakdown due to the conductive foreign matter caught in the sliding contact surface, there is a strong tendency that the dust-proof requirement for the casing, which is the outer shell of the connector, becomes stricter.

Furthermore, since the electrical insulating ring gradually wears both the flat plate-shaped stationary ring and the flat plate-shaped rotating ring, there is a problem that a lubricant must be firmly applied to both surfaces of the electrical insulating ring. .

Another conventional example is Japanese Patent Laid-Open No. 60-354.
No. 82 is a current collector assembly applied to a cable winding reel of an overhead crane, in which rotating current collecting rings 22 and 25 that rotate integrally with the shaft 10 are provided outside fixed current collecting rings 23 and 24. Provided and fixed ring 23, 24
The plurality of plug members 27 provided in each of the fixing rings are axially pressed against the rotating rings 22 and 25 by the biasing force of the spring assembly 26 arranged between the pair of fixing rings to transfer electricity between the fixing and rotating rings. There are things that are doing. According to this, however, the fixing and rotating rings of each pair do not directly contact each other as in the present invention but contact through three plugs 27, and the fixing and rotating rings of each pair have the same structure as the present invention. There is a drawback in that the structure is complicated and maintenance is troublesome because it requires a spring assembly 26 including a plurality of hollow sleeves 46 and coil springs 45 instead of an insulating plate. Since the rotating rings are not arranged alternately as in the present invention but the rotating rings 22 and 25 are arranged on both outer sides of the pair of fixed rings 23 and 24, respectively, the number of parts is increased. However, there is a disadvantage in that the assembly and disassembly procedures are complicated as well. The present invention has been made in view of these points, the insulating layer is integrally formed in advance on either one of the fixed and rotating flat plates and punched, and both flat plates are alternately assembled, whereby The object is to solve the problems or drawbacks of the conventional example.

[0011]

In order to achieve the above object, the rotary electric connector according to the present invention comprises a shaft (2).
And a plurality of conductive contact pairs (3), each pair comprising an electrically conductive fixed plate (6) and an electrically conductive rotating plate (7), and each pair being an insulating plate. (8) is insulated, and the fixed flat plates are non-rotatably fitted and locked to the shaft body in a state orthogonal to the axis, and the rotary flat plates are fixed to the shaft body. The plurality of pairs of conductive contact pairs (3), which are rotatably in a state perpendicular to the axis and are in surface contact with the fixed and rotating flat plates, and the fixed flat plate and the rotary flat plate of each pair are pressed against each other. In the rotary electric connector, the pressing means (4, 5) for electrically connecting the rotating flat plates and the restricting means (5a, 7b) for restricting the plurality of rotary flat plates to rotate integrally with each other are provided. The fixed plate (6) and rotating plate (7) of the contact pair are all They are alternately arranged as,
Moreover, the insulating plate (8) is preliminarily formed as an insulating layer (8) on one surface of either one of the fixed and rotating flat plates of the conductive contact pairs of each pair, and then the flat plate of either one of the flat plates is formed. The insulating layer integrally formed on the one flat plate is formed by press punching into a predetermined shape together with the other flat plate that is in surface contact with the insulating layer, and the relative rotation of the one and the other flat plates is performed. It is characterized in that it slides and slides at a speed that matches the speed.

[0012]

According to the above structure, a plurality of pairs of conductive contact fitted on the shaft body are formed by press punching after integrally forming an insulating layer on either one of the fixed plate and the rotating plate, and the two plates are alternately assembled. By attaching them, the number of parts and the number of assembling steps can be reduced, and the apparatus can be downsized and maintenance can be facilitated.

[0013]

Embodiments of the present invention will be described below with reference to FIGS. 1 is a sectional view showing a cord reel device to which an embodiment of the rotary electric connector of the present invention is applied, FIG. 2 is an exploded perspective view of the rotary electric connector shown in FIG. 1, and FIGS. FIG. 2 is a plan view and a side view of the rotary plate shown in FIG. 1, respectively.

The rotary electric connector 1 of the cord reel device shown in FIGS. 1 and 2 uses a stationary spline shaft 2 made of an electric insulator having a spline groove 2a as a shaft body, and an electric cord is formed on the spline shaft 2. A plurality of (here, three) conductive contact pairs 3 and pressure plates 5 connected to a plurality of core wires are externally fitted, and the coil springs 4 serving as pressing means press the conductive contact pairs 3 through the pressure plates 5 in pressure contact with each other. It is configured to maintain a conductive state.

The spline shaft 2 is formed by molding an insulating resin material into a hollow columnar body, and a snap ring groove 2b is formed near the tip of the spline shaft 2 outside the four spline grooves 2a running axially on the outer peripheral surface. I am doing it. Further, the spline shaft 2 is integrally formed with a collar portion 2c serving as a stopper at an axially intermediate portion, and three conductive contact pairs 3 are sandwiched and held between the collar portion 2c and the pressure plate 5. It As shown in FIG. 1, the stationary spline shaft 2 has one end fitted and fixed to the fixed central shaft 31 and the other end fixed to the cover 33 of the bracket 32 with a screw 34.

The conductive contact pair 3 comprises a fixed copper plate 6 connected to one core wire on the stationary side and a rotating flat plate 7 made of copper connected to one core wire on the rotating side. The fixed flat plate 6 and the rotary flat plate 7 are rotatably fitted to the spline shaft 2 in a state orthogonal to the axis thereof so that the flat plates 6 and 7 are in surface contact with each other.

As shown in FIG. 2, the fixed flat plate 6 is made of a C-ring-shaped copper plate having an inner diameter to be fitted on the spline shaft 2, and the lead piece 6b extends from the inner tooth 6a formed on the inner peripheral portion of the ring. Thus, the lead piece 6b is bent at a right angle. Reference numeral 6c denotes a rice grain-sized boss portion projecting on a surface that comes into surface contact with the rotating flat plate 7, and the upper surface of the boss portion is a flat surface.

As shown in FIGS. 2, 3 and 4, the rotary flat plate 7 is formed by press punching a copper plate to which an insulating layer 8 is adhered, and the flat plate 6 and the fixed flat plate 6 which are loosely fitted to the spline shaft 2.
The same ring-shaped insulating layer 8 is integrated with a copper ring having a larger outer diameter. On the outer periphery of the rotating flat plate 7, there is one protrusion 7a for connecting the electric wire,
In addition, notches 7b are provided at four positions for restraining rotation, and the holes formed in the protrusions 7a are used for connecting the core wires. A total of three core wires connected to each of the protrusions 7a are combined with one rotation-side electric cord and wound around the outer periphery of a rotary drum 36 described later.

The pressure plate 5 is made of a ring-shaped electrical insulating material having an inner and outer diameters which are substantially the same as those of the rotary flat plate 7, and its four legs 5a.
Respectively engage through the cutouts 7b of the rotary flat plate 7, and further, the side plate 36a of the rotatable drum 36 of the cord reel device.
Is engaged with each hole 36b. As a result, the pressure plate 5, the rotary flat plate 7, and the drum 36 are regulated to rotate integrally.

The insulating layer 8 formed integrally with the rotary flat plate 7 includes:
For example, Teflon (polytetrafluoroethylene) having a predetermined thickness adhered to a copper plate via an adhesive is used. In order to manufacture the rotating flat plate 7 with an insulating layer, first, one surface of a sheet-shaped copper plate is washed with a solvent such as methyl ethyl ketone and sufficiently dried until it can be used as an adhesive surface. Next, an epoxy adhesive is applied to the adhesive surface of the copper plate, and a Teflon sheet is attached to the adhesive surface. At this time, for example, the surface pressure is 4 to 5 kg /
Press the Teflon sheet with cm ² and press it to 14-1
Hold for about 5 minutes. When a predetermined time has elapsed, the pressure is released, and the adhesive protruding from the adhesive surface to the edge of the sheet is removed. In this way, when a copper plate sheet having Teflon adhesively coated on one side is completed, the copper plate sheet with an insulating layer is finally punched by a punching press to finish it into the predetermined shape as shown in FIGS.

When assembling the rotary electric connector 1,
First, the inner teeth 6a and the lead piece 6b of the fixed flat plate 6 of the first conductive contact pair 3 are fitted into the first spline groove 2a of the spline shaft 2, and the lower surface of the fixed flat plate 6 is sandwiched by a washer 9 to form a collar. The part 2c is abutted and locked. Next, the rotary flat plate 7 having the insulating layer 8 integrally formed on the upper surface thereof is fitted into the spline shaft 2 and slidably brought into contact with the fixed flat plate 6 so that the spline shaft 2 is externally attached so as to obtain a normal conduction state. Fit.

Subsequently, the inner teeth 6a and the lead piece 6b of the fixed flat plate 6 of the second conductive contact pair 3 are fitted into the second spline groove 2a of the spline shaft 2, and the lower surface of the fixed flat plate 6 is set to 1
The upper surface of the insulating layer 8 of the rotary flat plate 7 of the set is brought into contact with and locked.
Similarly, the rotating flat plate 7 having the insulating layer 8 integrated on the upper surface
Is fitted into the spline shaft 2 and slidably brought into contact with the fixed flat plate 6 to be fitted onto the spline shaft 2 so as to obtain a normal conduction state. Then, the third conductive contact pair 3 is also fitted onto the spline shaft 2 in the same manner as the second set.

After that, the three sets of rotary flat plates 7 are appropriately rotated to align the notches 7b formed at the four positions in the same phase, and as described above, the leg portions 5a of the pressure plate 5 are provided in these notches. The pressure plate 5 is engaged with the spline shaft 2
Insert into. Finally, the washer 10 and the coil spring 4 are fitted into the spline shaft 2, and the lower end of the coil spring 4 is locked to the upper surface of the pressure plate 5 via the washer 10.
The upper end of the coil spring 4 is locked to the snap ring 11 fitted in the snap ring groove 2b at the tip of the spline shaft 2, and the assembly is completed. In addition, three fixed flat plates 6
Each core wire (not shown) in the fixed-side electric cord is connected to a lead piece 6b extending from the lead piece 6b.
As shown in FIG. 1, the tip of b is bent and fixed to the bracket 32 with a screw 35.

As described above, since the rotary electric connector 1 of the cord reel has the insulating layer 8 integrally formed on the fixed flat plate 6 or the rotary flat plate 7 in advance, the insulating layer 8 is assembled as a single electric insulating ring. Compared with the conventional product, the number of parts can be reduced by 2 to 3 even in the case of the cord reel of the three-core cord, and the configuration becomes extremely simple. Also, since the number of parts is small, assembly and disassembly work is easy,
The work can be performed quickly, and the application to the automatic assembly line becomes extremely easy. Further, since the insulating layer 8 is formed integrally with the rotating flat plate 7 in advance and then punched out, the outer shape of the insulating layer 8 itself is larger than that of forming the insulating plate 8 and the fixed flat plate 6 or the rotating flat plate 7 separately. It is not necessary to perform molding or to align the insulating layer 8 and the fixed flat plate 6 at the time of assembling, and the number of steps can be significantly reduced. Further, since the insulating layer 8 and the rotary flat plate 7 are completely intimately integrated with each other, there is no sliding contact portion between them, and therefore lubrication between them is unnecessary, and further, dielectric breakdown due to foreign matter being caught is prevented. Without fear, stable performance can be maintained over a long period of time.

Although the insulating layer 8 is formed integrally with the rotary flat plate 7 in the above-described embodiment, the insulating plate 23 is formed on the fixed flat plate 22 like the rotary electric connector 21 shown in FIG.
It is also possible to integrate into. Also in this case, the fixed flat plate 22 with an insulating layer may be formed by pressing a copper plate and a Teflon sheet bonded together with an adhesive into the shape shown in FIGS. 6 and 7, and then erecting the lead piece 22b. In the embodiment, the fixed flat plate 22 that comes into surface contact with the rotary flat plate 24 is not provided with a boss portion, so that the fixed flat plate 22 and the rotary flat plate 24 are in contact with each other over the entire flat surface.

In each of the above embodiments, the insulating layer 8,
23 is not limited to the method of unifying by bonding, but it is also possible to spray the insulating material to a predetermined thickness on one of the rotating flat plates 7 and 24 or the fixed flat plates 6 and 22, for example. The material of the insulating layers 8 and 23 is not limited to Teflon.

[0027]

The invention according to claim 1 of the present application has the following advantages.

Since the insulating layer is preliminarily formed integrally with a fixed or rotating flat plate, it has been disclosed in Japanese Patent Laid-Open No. 60-35482.
As described in No. 63, a number of separate plug members are required between the fixed and rotating flat plates, or 3 as in Japanese Utility Model Publication No. 63-9115.
Compared with the one that requires three separate insulating plates for a pair of fixed and rotating flat plates, these individual plug members or insulating plates are unnecessary, and when applied to a cord reel of a three-core wire cord, for example, Since the number of parts can be reduced by at least three, the configuration can be extremely simplified.

Since the insulating layer is integrally formed on either a fixed or a rotating flat plate, the insulating plate has a structure in which a separate insulating plate is interposed between the flat plates as in JP-B-63-9115. Compared to a flat plate that floats independently and tends to rotate irregularly, the insulating layer is always fixed to one flat plate that is always integral with one flat plate and is in contact with the insulating layer. Sliding contact can be performed at a stable speed that matches the relative speed between the rotating flat plates, so the sliding contact sliding state can be made smooth and stable, and especially when using a material with a low friction coefficient for the insulating layer, extremely smooth sliding rotation The advantage is that it can provide motion.

Since the fixed and rotary flat plates are arranged alternately as a whole when viewed as a whole, a plurality of plugs are provided on the outer side of the pair of inner fixed flat plates as in the prior art JP-A-60-35482. Compared to the case where a pair of rotary flat plates are provided through members, the number of parts is increased and the assembly procedure is complicated, but both flat plates with integrated insulating layers are simply arranged alternately as described above. Therefore, the structure is very simple, the number of parts is small, the size in the axial direction can be reduced, and the size can be reduced, and the assembling and disassembling operations can be performed very simply because both flat plates are alternately performed.

The integrated flat plate and insulating layer are formed by press punching the large flat plate and insulating layer at once to form the ring shape. The shape can be formed in one step, and the number of steps can be significantly reduced.

[0032]

[Brief description of drawings]

FIG. 1 is a sectional view showing a cord reel device to which an embodiment of a rotary electric connector of the present invention is applied.

2 is an exploded perspective view of the rotary electric connector shown in FIG. 1. FIG.

FIG. 3 is a plan view of the rotary plate with an insulating layer shown in FIG.

FIG. 4 is a side view of the rotary plate with an insulating layer shown in FIG.

FIG. 5 is an exploded perspective view showing another embodiment of the rotary electric connector of the present invention.

6 is a plan view showing the shape of the fixed flat plate with an insulating layer shown in FIG. 5 during processing.

7 is a side view of the fixed flat plate with an insulating layer shown in FIG.

[Explanation of symbols]

 1,21 Rotary electrical connector 2 Spline shaft 3 Conductive contact pair 4 Coil spring 6,22 Fixed plate 7,24 Rotating plate 8,23 Insulating layer 32 Bracket 36 Rotating drum

Claims (12)

(57) [Claims] 1. A shaft (2) and a plurality of pairs of conductive contact pairs (3), each pair comprising a conductive fixed plate (6) and a conductive rotating plate (7), In addition, the respective pairs are insulated from each other through an insulating plate (8), and the respective fixed flat plates are non-rotatably fitted and locked to the shaft body in a state orthogonal to the axis thereof. The plural pairs of conductive contact pairs (3) fitted so that the rotary plate is rotatable with respect to the shaft body in a state orthogonal to the axis thereof and is in surface contact with the fixed and rotary plates, and each pair. Of the fixed plate and the rotating plate, which are brought into pressure contact with each other to bring them into conduction, and a restricting device (5a, 7b) for restricting the plurality of rotating plates to rotate integrally with each other. Type electrical connector, the fixed flat plate (6 ) And rotating plate
(7) and the insulating plate (8) are arranged alternately as a whole, and the insulating plate (8) is preliminarily provided with an insulating layer (8) on one surface of one of the fixed and rotating flat plates of the conductive contact pairs. ) after being integrally formed as a formed by press punching into a predetermined shape with該何Re or the other flat plate, which
The insulating layer integrally formed on the one flat plate by
The other flat plate that is in surface contact with the edge layer
Sliding and sliding at a speed that matches the relative rotation speed of both flat plates
Performing, rotary electrical connector, characterized in that. 2. One of the fixed and rotating flat plates of the conductive contact pair of each pair is characterized in that an insulating layer (8) is integrally formed on one surface thereof in advance and then punched into a predetermined shape. The method for manufacturing a rotary electric connector according to claim 1. 3. The connector according to claim 1, wherein the insulating layer (8) is formed by spraying an insulating material onto the rotating flat plate to a predetermined thickness. 4. The connector according to claim 1, wherein the fixed flat plate (6) and the rotary flat plate (7) are copper plates,
The connector, wherein the insulating layer (8) is an insulating material having a predetermined thickness adhered to the copper plate via an adhesive. 5. The connector according to claim 4, wherein the insulating material is polytetrafluoroethylene. 6. The rotary electrical connector according to claim 1, wherein the shaft body (2) has a first locking portion (2a), and the fixed flat plate is provided. (6) has a second locking portion (6b), and this second locking portion is locked to the first locking portion so as to be non-rotatably locked to the shaft body. The above connector. 7. A shaft (2) and a plurality of pairs of conductive contact pairs (3) connected to a plurality of core wires forming an electric cord, each pair being connected to one core wire on the fixed side. And a conductive rotating flat plate (7) connected to one core wire on the rotating side, and each pair is insulated from each other through an insulating plate (8). In addition, each fixed flat plate is non-rotatably locked to the shaft body in a state orthogonal to the axis line,
A plurality of conductive contact pairs (3) fitted so that the flat plate is rotatable with respect to the shaft body and in surface contact with the fixed and rotating flat plates, and Pressing means (4, 5) for bringing the fixed flat plate and the rotary flat plate into pressure contact with each other for conduction, and a rotary drum (not shown) that is rotatably arranged coaxially with the shaft body and around which the rotary side electric cord is wound ( 36) and regulating means (5a, 7b, 3) for regulating the plurality of rotating flat plates (7) and the rotating drum (36) to rotate integrally with each other.
6b) and a rotary electrical connector comprising
And the fixed flat plate (6) and the rotary flat plate of the conductive contact pair of each pair.
(7) are arranged alternately as a whole, and the insulating plate (8) is preliminarily provided with an insulating layer (1) on one surface of one of the fixed flat plate and the rotary flat plate of each conductive contact pair. after being formed integrally 8), it is formed by press punching into a predetermined shape with該何Re or the other flat plate, this
Insulating layer which is integrally formed on the flat plate of the hand by Les, said
The one and the other with respect to the other flat plate that is in surface contact with the insulating layer
Sliding at a speed that matches the relative rotation speed of the two flat plates
A rotary electric connector for a cord reel, which is characterized by performing movement . 8. An insulating layer (8) is previously formed on one surface of one of the fixed and rotating flat plates of the conductive contact pairs of each pair.
8. The method for manufacturing a rotary electric connector for a cord reel according to claim 7, wherein the cord is integrally formed and then punched into a predetermined shape. 9. The connector according to claim 7, wherein the insulating layer (8) is formed by spraying an insulating material on the rotary flat plate to a predetermined thickness. 10. The connector according to claim 7, wherein the fixed flat plate (6) and the rotary flat plate (7) are copper plates,
The connector, wherein the insulating layer (8) is an insulating material having a predetermined thickness adhered to the copper plate via an adhesive. 11. The of claim 10 connectors, said insulating material, said connector, which is a Poritetorafu Le Oroechiren. 12. The rotary electrical connector according to claim 7, 9 or 11, wherein the shaft body (2) has a first locking portion (2a), and the fixed flat plate. (6) has a second locking portion (6b), and this second locking portion is locked to the first locking portion so as to be non-rotatably locked to the shaft body. The above connector.