JP2004362974A - Rotary connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary connector not get into such a state that a neutral fixing pin is broken and a part of it remains in a cable casing when releasing the temporal fixation of the neutral fixing pin, and the remaining part contacts and interferes a steering cover and a column cover, to generate abnormal sound and makes the steering impossible to rotate. <P>SOLUTION: A neutral fixing pin 28 comprises a flat pin 36 engaged with a slot 24 disposed on an outer side of an outer periphery wall 18; an arm 46 connected to the flat pin 36 via a brittle portion 44; a round pin 48 engaged with a hole 26 disposed on an upper face of an upper end wall 16; and a finger hooking portion 50 connected to the arm 46. The brittle portion 44 is positioned inside an opening end 32 of the slot 24 and the opening end 32 is positioned at a position lower than the upper face of the upper end wall 16. A finger hooking face 52 of the finger hooking portion 50 forms an angle of 45° against the upper face of the upper end wall 16 and the brittle portion 44 is positioned on the extension of a finger hooking face 52. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rotary connector, and more particularly, to a rotary connector used for transmitting an electric signal, an optical signal, or electric power between a fixed body and a rotating body.
[0002]
[Prior art]
The rotary connector electrically connects, for example, the vehicle body side (fixed body) and the steering shaft side (rotary body) of the automobile, and transmits a start signal from the vehicle body side to an airbag system installed on the steering shaft. Used for Such a rotary connector is usually provided with a cable casing in which an annular chamber is formed between an outer fixed case and an inner rotary case rotatably installed in the outer fixed case, and spirally housed in the annular chamber of the cable casing. And a flat cable.
[0003]
By the way, when the rotating connector is mounted on the vehicle body side, the number of times that the inner rotating case can be rotated clockwise and the number of times that the inner rotating case can be rotated counterclockwise must be set to be substantially the same. In this setting state, the flat cable is in the neutral state, and the inner rotating case is in the neutral position with respect to the outer fixed case.
Normally, after the flat cable is set to the neutral state, a neutral fixing pin is attached to the cable casing, and temporary fixing for locking the rotation of the inner rotating case with respect to the outer fixing case is performed. For example, Patent Document 1 discloses an example of a rotary connector in which such temporary fixing is performed.
[0004]
Here, the neutral fixing pin has a horizontally extending arm, an annular finger hook connected to one end of the arm, and a direction substantially orthogonal to the other end of the arm via the thin portion. And a fixed remainder. Then, the temporary fixing is performed by inserting the remaining fixed portion into the slot provided on the outer peripheral wall of the outer fixed case and inserting the projection provided on the upper end wall of the inner rotating case into the hole of the arm portion. On the other hand, when releasing the temporary fixing, the user puts his finger on the finger hook and lifts the neutral fixing pin away from the cable casing. At this time, the thin portion having low mechanical strength is broken, and the remaining fixed portion remains in the slot.
[0005]
For this reason, with respect to the rotary connector having no finger-holding portion or the like of the neutral fixing pin, by visually checking whether or not the remaining fixed portion remains in the slot, the history of the temporary fixing using the neutral fixing pin is performed. Is easily determined. That is, the existence of the remaining fixed portion proves that the flat cable was temporarily fixed to the neutral state. As a result, it is possible to contribute to avoiding unnecessary confusion when releasing the temporary fixing and attaching the rotary connector to, for example, the vehicle body side of an automobile.
[0006]
[Patent Document 1]
JP-A-9-293576
[Problems to be solved by the invention]
However, the rotary connector described in Patent Document 1 has the following problem.
That is, the thin portion of the neutral fixing pin is located above the upper end surface of the inner rotating case. For this reason, even after the thin portion is broken and the temporary fixing is released, the upper end of the remaining fixed portion remaining in the slot of the outer peripheral wall of the outer fixed case projects upward from the upper end surface of the inner rotating case. As a result, for example, when the rotating connector is fixed to the vehicle body side of the automobile and the temporary fixing is released, a steering cover or a column cover for covering the rotating connector and the peripheral devices is attached, and the upper end of the remaining fixed portion becomes the steering cover or the like. Inconveniences such as generation of abnormal noise and inability to rotate the steering wheel occurred due to contact and interference with the column cover.
[0008]
Further, a surface of the neutral fixing pin, on which the finger of the finger hooking portion contacts, is parallel to the upper end surface of the inner rotating case. Therefore, when a force is applied by touching the surface with a finger to lift the neutral fixing pin, the force is directed in a direction perpendicular to the upper end surface of the inner rotating case. Therefore, although the force is also exerted in the direction in which the finger hook rotates with the thin portion as the fulcrum due to the presence of the arm, the force component in this direction does not become so large. As a result, there is a possibility that the fixed remaining portion is separated from the slot and does not remain without the thin portion being easily broken.
[0009]
The present invention has been made in consideration of the above circumstances, and when releasing the temporary fixing by the neutral fixing pin, the neutral fixing pin is broken and a part thereof is left in the cable casing, and the residue is For example, an object of the present invention is to provide a rotating connector that does not generate abnormal noise or disable steering rotation by contacting or interfering with a steering cover or a column cover that covers a rotating connector fixed to an automobile body. And It is another object of the present invention to provide a rotary connector in which a neutral fixing pin can be easily broken.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, a cable casing having an inner case and an outer case provided relatively rotatably, and having an annular chamber formed between the inner and outer cases, The inner case and the outer case were housed in a wound state in the annular chamber to electrically connect between the inner case and the outer case, and were allowed to be wound or unwound from a neutral state according to the relative rotation of the inner and outer cases. In a rotary connector including a flat cable and a neutral holding device that holds the inner and outer cases relatively non-rotatably in a neutral state of the flat cable, the inner case forms one end wall of the cable casing. , The outer case forms an outer peripheral wall of the cable casing, and the neutral holding device has a central axis of the annular chamber on the outer peripheral wall. A concave first engagement portion that is provided substantially parallel to the one end wall and has an open end, and the open end is positioned on the other end wall side of the cable casing from a reference surface including an outer surface of the one end wall; A second engagement portion provided on the one end wall, a first projection engagement portion fitted to the first engagement portion, and a second engagement portion fitted to the second engagement portion. And a neutral fixing pin for connecting the outer case and the inner case, wherein the neutral fixing pin includes an arm connecting the first and second locking portions, and a finger hook provided on the arm. A rotary connector is provided, comprising: a portion, a first connecting portion, and a fragile portion that connects the first locking portion and the arm and is positioned within the open end of the first engaging portion.
[0011]
In this rotary connector, the opening end of the first engagement portion is located on the other end wall side with the outer surface of the one end wall as a reference surface, and the arm of the first engagement portion fitted to the first engagement portion. Since the fragile portion forming the connecting portion is positioned within the open end, the fragile portion is broken by applying a predetermined force to the finger hook portion, and when the temporary fixing by the neutral fixing pin is released, the first locking portion Remains in the first engagement portion, and the fragile portion forming the upper end of the first engagement portion does not protrude outside the outer surface of the one end wall of the cable casing. Therefore, after the rotating connector is fixed to, for example, the vehicle body side of the automobile and the temporary fixing is released, when the steering cover or the column cover for covering the rotating connector and peripheral devices is attached, the rotating connector remains in the first engagement portion. The upper end of the first locking portion does not come into contact with or interfere with the column cover or the steering cover, and as a result, no abnormal noise is generated or the steering cannot be rotated.
[0012]
Here, the finger hook extends radially inward of the annular chamber from an end of the arm on the side of the first locking portion, and forms an acute angle with the outer surface of the one end wall. It is preferred to have a surface. In this case, when a finger is applied to the finger-holding surface to apply a force, most of the force is a force in a direction in which the finger-holding portion rotates around the fragile portion as a fulcrum. Therefore, the fragile portion is easily broken, and the temporary fixing by the neutral fixing pin is released.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a rotary connector according to an embodiment of the present invention will be described with reference to the accompanying drawings.
As shown in FIG. 1, the rotary connector according to the present embodiment includes a cable casing 10. The cable casing 10 has an inner rotating case 12 and an outer fixed case 14, and an annular chamber is formed between the inner rotating case 12 and the outer fixed case 14. In the annular chamber, a flat cable (not shown), which is a flexible band-shaped transmission line for transmitting an electric signal, an optical signal or electric power, is spirally wound and accommodated.
[0014]
The inner rotating case 12 forms an inner peripheral wall of the cable casing 10 and a ring-shaped upper end wall 16, and rotates in both forward and reverse directions about the center axis Ax of the annular chamber with respect to the outer fixed case 14. The outer fixed case 14 forms a ring-shaped lower end surface with the outer peripheral wall 18 of the cable casing 10. On the upper end wall 16, there is provided a rotary connector section 20 to which the inner end of the flat cable is electrically connected, and to the outer side of the outer peripheral wall 18, the outer end of the flat cable is electrically connected. A fixed connector section 22 is provided.
[0015]
The cable casing 10 is provided with a neutral holding device for holding the rotation of the inner rotating case 12 with respect to the outer fixed case 14 in a state where the flat cable is in a neutral state. The neutral holding device includes a slot 24 as a first engagement portion provided outside the outer peripheral wall 18, a hole 26 as a second engagement portion provided on the upper surface of the upper end wall 16, A neutral fixing pin 28 is fitted into each of the holes 26 to connect the outer fixed case 14 and the inner rotating case 12 to each other.
[0016]
As shown in FIG. 2, the slot 24 is provided substantially parallel to the center axis Ax of the annular chamber between the outer peripheral wall 18 and the slot wall 30 provided outside thereof, and has an open end on the upper end wall 16 side. 32. The open end 32 is positioned on the lower end wall side of the cable casing 10 with the upper surface of the upper end wall 16 as a reference plane. That is, the open end 32 provided above the slot 24 is at a position lower than the upper surface of the upper end wall 16. Further, a step portion 34 protruding into the slot 24 is formed in the slot wall 30.
[0017]
As shown in FIGS. 2 and 3, the neutral fixing pin 28 has a substantially flat flat pin 36 as a first locking portion fitted into the slot 24. The tip of the flat pin 36 is divided into three by two slits 38, and a snap piece 40 is provided in the middle part. A projection 42 is provided on the other end of the flat pin 36 at a predetermined distance from the snap piece 40.
[0018]
The other end of the flat pin 36 is a weakened portion 44 which is formed with a wedge-shaped notch and is thinned. The fragile portion 44 is located inside the open end 32 with the neutral fixing pin 28 attached to the cable casing 10, that is, with the flat pin 36 fitted into the slot 24. That is, the fragile portion 44 is located at a position lower than the upper surface of the upper end wall 16.
[0019]
An arm 46 is connected to the flat pin 36 via a fragile portion 44. The arm 46 extends upward from the weak portion 44 along the outer peripheral wall 18 and wraps around the upper surface of the upper end wall 16 with the flat pin 36 fitted in the slot 24. A substantially cylindrical round pin 48 as a second locking portion fitted to the hole 26 is provided at a lower end of the arm 46 which has been turned around the upper surface of the upper end wall 16.
[0020]
A ring-shaped finger hook 50 is connected to the arm 46. The finger hooking surface 52 of the finger hooking portion 50 extends radially inward of the annular chamber from the end of the arm 46 on the flat pin 36 side, and is orthogonal to the central axis Ax of the annular chamber, that is, of the upper end wall 16. At an acute angle to the top surface. Here, the case where the finger hooking surface 52 forms an angle of 45 ° with the upper surface of the upper end wall 16 and the fragile portion 44 is located on the extension of the finger hooking surface 52 is illustrated.
[0021]
Next, a procedure for performing temporary fixing using the neutral holding device will be described.
First, the flat cable spirally housed in the annular chamber of the cable casing 10 is set to a neutral state. In this state, the neutral fixing pin 28 is mounted on the cable casing 10. Specifically, as shown in FIG. 2, the flat pin 36 and the round pin 48 of the neutral fixing pin 28 are fitted into the slot 24 and the hole 26, respectively.
[0022]
At this time, the snap piece 40 of the flat pin 36 is inserted into the slot 24 while pressing the step portion 34 of the slot wall 30, and at the stage where the insertion is completed, the upper end of the snap piece 40 and the lower end of the protrusion 42 are respectively stepped. It contacts the lower and upper ends of the part 34. For this reason, the step portion 34 is sandwiched between the snap piece 40 and the protrusion 42, and the flat pin 36 cannot easily come out of the slot 24.
[0023]
By attaching the neutral fixing pin 28 to the cable casing 10 in this manner, the outer fixed case 14 and the inner rotating case 12 are connected, and the temporary fixing for locking the rotation of the inner rotating case 12 with respect to the outer fixed case 14 is completed. .
Next, a procedure for releasing the temporary fixing will be described.
After fixing the outer fixed case 14 of the rotating connector in the temporarily fixed state to, for example, the vehicle body of the automobile, the terminal on the vehicle body side of the automobile is electrically connected to the fixed connector portion 22 of the outer fixed case 14 while the inner rotating case 12 is fixed. The terminal on the steering shaft side is electrically connected to the rotary connector section 20 of the first embodiment. Thus, the vehicle body side and the steering shaft side are electrically connected via the flat cable in the annular chamber of the rotary connector.
[0024]
Subsequently, the neutral fixing pin 28 is detached from the cable casing 10. Specifically, a finger is inserted into the ring-shaped finger hook portion 50 of the neutral fixing pin 28, and a finger is applied to the finger hook surface 52 to apply a force to cause the round pin 48 to escape from the inside of the hole 26. The fragile portion 44 is broken.
At this time, the finger hooking surface 52 of the finger hooking portion 50 is not parallel to the upper surface of the upper end wall 16 but forms an acute angle of 45 ° with the upper surface thereof. Is located. For this reason, almost all of the force applied to the finger-holding surface 52 is a component in the direction of rotating the finger-holding portion 50 with the fragile portion 44 as a fulcrum, as schematically shown by a white arrow in FIG. . Therefore, the fragile portion 44 is easily broken. That is, as was feared in the case of Patent Document 1, most of the force applied to the finger hook 50 goes in a direction perpendicular to the upper surface of the upper end wall 16, and the inside of the slot 24 remains without the fragile portion 44 being easily broken. Never get out of
[0025]
As a result, the neutral fixing pin 28 is divided into two by the fragile portion 44, one of the finger hooks 50, the arm 46 and the round pin 48 is separated from the cable casing 10 and remains in the hand, and the other flat pin 36 is 24. In this way, the temporary fixing is released, and the inner rotating case 12 can freely rotate in the forward and reverse directions with respect to the outer fixed case 14.
[0026]
Thereafter, as shown in FIG. 4, a column cover 54 for covering the equipment on the vehicle body side and a steering cover 56 for covering the equipment on the steering shaft side are attached to the periphery of the rotary connector. It is preferable that the column cover 54 and the steering cover 56 cover the rotary connector as much as possible without impeding the rotation of the inner rotary case 12. For this reason, the case where the end of the column cover 54 extends to the vicinity of the upper end of the outer peripheral wall 18 and the end of the steering cover 56 extends to the outer peripheral part of the upper surface of the upper end wall 16 is illustrated.
[0027]
However, even in this case, the broken fragile portion 44 forming the upper end of the flat pin 36 remaining in the slot 24 is located at a position lower than the upper surface of the upper end wall 16, so that the column cover 54 and the steering cover 56 Does not come into contact with or interfere with the flat pin 36, so that there is no occurrence of abnormal noise or inability to turn the steering wheel. On the other hand, in the case of Patent Document 1, since the upper end of the fixed remaining portion remaining in the slot protrudes above the upper end surface of the inner rotating case, it comes into contact with and interferes with the steering cover and the column cover, thereby generating abnormal noise. There is a possibility that the steering wheel will not be able to rotate or the steering wheel will not be able to rotate.
[0028]
As described above, according to the present embodiment, the finger-holding surface 52 of the neutral fixing pin 28 forms an acute angle of 45 ° with the upper surface of the upper end wall 16, and the fragile portion 44 extends , Almost all of the force applied to the finger hooking surface 52 is a component in the direction of rotating the finger hooking portion 50 with the fragile portion 44 as a fulcrum. Therefore, the fragile portion 44 can be easily broken, and the temporary fixing of the rotary connector can be released.
[0029]
Further, even when the temporary fixing is released, since the flat pin 36 remains in the slot 24, it is possible to confirm at a glance the history of the rotational connector being temporarily fixed.
Further, since the weak portion 44 forming the upper end of the flat pin 36 remaining in the slot 24 is located in the open end 32 and lower than the upper surface of the upper end wall 16, the rotary connector is fixed to, for example, the vehicle body side of the automobile. Then, when the column cover 54 and the steering cover 56 are attached to the periphery of the rotary connector after the temporary fixing is released, the upper end of the flat pin 36 in the slot 24 may contact or interfere with the column cover 54 or the steering cover 56. Can be prevented, and the occurrence of abnormal noise, the inability to rotate the steering wheel, and the like can be avoided.
[0030]
In the above-described embodiment, the case where the finger hook 50 of the neutral fixing pin 28 has a ring shape as shown in FIG. 2 has been described, but the shape of the finger hook 50 is not limited to the ring shape. Instead, for example, a flat-shaped finger hook 50 as shown in FIG. 5 may be used. Also, the angle and the arrangement position of the finger hooking surface 52 are limited to the case where the angle is 45 ° with respect to the upper surface of the upper end wall 16 and the fragile portion 44 is located on the extension of the finger hooking surface 62. Not something. As long as the finger hook 50 is shaped so that a finger can be easily hooked thereon, and almost all of the force applied to the finger hooking surface 52 is a component in the direction of rotating the finger hook 50 with the fragile portion 44 as a fulcrum, various methods are available. Is possible.
[0031]
In addition, although the description has been given of the rotating connector device in which the inner case rotates and the outer case is fixed, the present invention is similarly applicable to a rotating connector in which the inner case is fixed and the outer case rotates.
[0032]
【The invention's effect】
As described above in detail, according to the present invention, the following effects can be obtained.
That is, according to the rotary connector of the first aspect, when the temporary fixing of the flat cable to the neutral state is released, the weak portion of the neutral fixing pin is broken, and the first locking portion remains in the first engaging portion. At the same time, it is possible to prevent the upper end of the first locking portion from protruding outside the outer surface of the one end wall of the cable casing. Therefore, even after the temporary fixing is released, it is possible to easily confirm the history of the temporary fixing of the rotary connector, and, for example, to cover the column around the rotary connector fixed to the body of the automobile. When installing the steering wheel or the steering cover, the upper end of the first locking portion in the first engagement portion is prevented from contacting or interfering with the column cover or the steering cover, thereby generating abnormal noise or making steering rotation impossible. Can be avoided.
[0033]
According to the rotary connector of the second aspect, when a force is applied by placing a finger on the finger-holding surface, most of the force becomes a force in a direction in which the finger-holding portion rotates around the fragile portion as a fulcrum. Therefore, the fragile portion can be easily broken, and the temporary fixing by the neutral fixing pin can be released.
[Brief description of the drawings]
FIG. 1 is a perspective view showing the appearance of a rotary connector according to an embodiment of the present invention.
FIG. 2 is a sectional view showing a neutral holding device of the rotary connector of FIG. 1;
FIG. 3 is a left side view of a neutral fixing pin of the neutral holding device shown in FIG. 2;
FIG. 4 is a cross-sectional view showing a state in which a column cover and a steering cover for covering a rotary connector and the like fixed to the body of the automobile are attached.
FIG. 5 is a cross-sectional view showing a neutral holding device of a rotary connector according to a modification of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Cable casing 12 Inner rotation case 14 Outer fixed case 16 Upper end wall 18 Outer peripheral wall 24 Slot 26 as a first engagement part Hole 28 as a second engagement part Neutral fixed pin 32 Open end 36 As a first engagement part Flat pin 44 Fragile portion 46 Arm 48 Round pin 50 as second locking portion Finger portion 52 Finger portion 54 Column cover 56 Steering cover

Claims (2)

A cable casing having an inner case and an outer case provided relatively rotatably, and an annular chamber formed between the inner and outer cases;
The inner case and the outer case were housed in a wound state in the annular chamber so as to be electrically connected to each other, and were allowed to be wound or unwound from a neutral state according to the relative rotation of the inner and outer cases. A flat cable,
A neutral connector having a neutral holding device that holds the inner and outer cases relatively non-rotatable in the neutral state of the flat cable,
The inner case forms one end wall of the cable casing, and the outer case forms an outer peripheral wall of the cable casing,
The neutral holding device,
The outer peripheral wall is provided substantially parallel to the central axis of the annular chamber, has an open end on the one end wall side, and the open end is on the other end wall side of the cable casing from a reference surface including an outer surface of the one end wall. A concave first engagement portion positioned at
A second engagement portion provided on the one end wall;
Neutral having a first engagement portion having a convex shape fitted to the first engagement portion and a second engagement portion fitted to the second engagement portion, and connecting the outer case and the inner case. Including a fixing pin,
The neutral fixing pin,
An arm connecting the first and second locking portions;
A finger hook provided on the arm;
A rotary connector for connecting the first locking portion and the arm, and having a weak portion positioned within the open end of the first engagement portion. The finger hooking portion extends radially inward of the annular chamber from an end of the arm on the first locking portion side, and has a finger hooking surface that makes an angle with an outer surface of the one end wall an acute angle. The rotary connector according to claim 1.

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