JP3920376B2 - Grounding clamp - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention fixes a shield tube having a function of shielding, bundling and protecting high-frequency noise of an electric wire harness to a chassis, a panel or the like (hereinafter referred to as a chassis or the like) and grounding (earth) connection thereto. Related to the clamp.
[0002]
[Prior art]
Conventionally, a shield tube made of a conductive material has been used to prevent high-frequency noise in the wire harness and to fix the wire harness to a conductive chassis or the like in a bundled state. A structure that is fixed to a chassis or the like by a fixing tool called a landing clamp has been proposed. FIG. 6 is a diagram showing an example thereof. The shield tube 2 is configured as a resin tube having a conductive plating and conductive coating on the surface, and a plurality of electric wire harnesses 3 are inserted into the shield tube 2. The Further, as shown in FIG. 5, the grounding clamp 1A has a main body portion 10A obtained by bending a metal piece into a substantially circular shape, and both end portions 101 are brought into contact with each other in a planar state to open a screw insertion hole 102. ing. A conductive band 20 made of conductive resin, rubber or the like is attached to the inner surface of the main body 10A.
[0003]
In this grounding clamp, the shield tube 2 is inserted into the main body portion 10A, and the screws 4 inserted through the screw insertion holes 102 are screwed into the chassis 5 or the like, whereby the both end portions 101 are fastened, and the main body portion 10A. The shield tube 2 is held inside. At this time, the shield tube 2 is brought into close contact with the conductive band 20 by the fastening force, and the end 101 of the main body portion 10A of the grounding clamp 1A is brought into close contact with the chassis 5 etc. Electrical connection is made to the chassis 5 through the sex band 20 and the main body 10A, and the shield tube 2 is held at ground (earth). As a result, the electric wire harness 3 inserted into the shield tube 2 is protected from external force by the mechanical strength of the shield tube 2 and is shielded from high-frequency noise when the shield tube 2 is grounded. .
[0004]
[Problems to be solved by the invention]
Such a conventional grounding clamp uses the conductive band 20 to electrically connect the main body 10 </ b> A to the shield tube 2, but to electrically connect the conductive band 20 to the chassis 5 or the like. For this, it is necessary to form the conductive film by forming or coating the conductive material on the surface of the main body 10A formed of a conductive material or an insulating material such as a resin material. For this reason, when forming with a general metal as an electroconductive material, manufacture of a clamp requires processes, such as metal cutting and press work, and there also exists a problem that the number of manufacturing processes becomes complicated. Further, when a conductive film is formed on the surface of a resin material or the like, there is a problem that the conductive film in the screwed portion is damaged by wear, the conductivity is deteriorated, and the shield function is lowered.
[0005]
An object of the present invention is to provide a grounding clamp that can be formed of a resin material but does not require the formation of a conductive film on the surface thereof, thereby making it possible to solve the above-mentioned problems all at once. There is to do.
[0006]
[Means for Solving the Problems]
The grounding clamp of the present invention is formed integrally with a resin material and clamped to a chassis or the like in a state where the shield tube is sandwiched, and extends along the clamping surface of the shield tube of the clamp body. The clamp body is provided with a defective portion for exposing the conductive band, and a protrusion disposed at a position facing the defective portion, and the clamp body portion is a chassis. And the like, the protrusion part presses and deforms the conductive band from the back side of the defect part, and the conductive band contacts the chassis or the like through the defect part. Moreover, as one embodiment of the present invention, the clamp main body portion is composed of a fixing piece and a fastening piece hinged to each other, and a conductive band that can be elastically deformed along the inner surface of the fixing piece and the fastening piece. The fixed piece is provided with a defective portion from which a part thereof is removed, and the fastening piece is provided with a protruding portion protruding to the fixed piece side at a position facing the defective portion, and the fixed piece is attached to the chassis or the like. It is set as the structure which fastens a fastening piece to a chassis etc. in the state made to contact.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of an embodiment of the present invention, and FIGS. 2 (a) and 2 (b) are a front view and a side view thereof. The grounding clamp 1 has a main body portion 10 formed by integrally molding a resin material. The main body portion 10 is formed by a fixed piece 11 and a fastening piece 12 so as to be generally cylindrical. Yes. The fixed piece 11 and the fastening piece 12 are connected by a hinge portion 13, and the fastening piece 12 is bent and deformed with respect to the fixed piece 11 by the hinge portion 13, and the end portion 111 of the fixed piece 11 and the end of the fastening piece 12 are When the portions 121 are brought into contact with each other, a cylindrical space is defined between them, and a shield tube can be sandwiched in the cylindrical space. A flexible resin made of conductive resin, rubber, urethane sponge, or the like is formed on the inner surface of the main body 10 in the region of the circular portions 112 and 122 extending from the fixed piece 11 through the hinge portion 13 to the fastening piece 13. A certain conductive band 20 is integrally attached with an adhesive.
[0008]
The fixing piece 11 constituting the main body 10 is notched with a required dimension from both sides at the end 111 formed at the end of the circular portion 112 formed in an arc shape somewhat smaller than the semicircular shape. The missing portion 113 is provided so that its width dimension is smaller than that of the circular portion 112, and the plate thickness of the end portion 111 is somewhat larger than that of the other portions. And the screw insertion hole 114 for fastening and fixing to a chassis etc. is opened in this thick part. Further, stoppers 115 raised upward are integrally formed on both sides in the width direction of the portion facing the end portion, and both sides of the conductive band 20 are constrained by the stoppers 115 so as to be conductive. The band 20 is configured not to be displaced in the width direction of the fixed piece 11. Note that the end of the conductive band 20 extends to the edge of the portion having a large plate thickness of the fixed piece 11, and the step of the plate thickness difference generated at the edge of the conductive band 20 The position in the length direction is constrained.
[0009]
On the other hand, the fastening piece 12 has an end portion 121 formed at an end portion of a circular portion 122 formed in an arc shape somewhat larger than a semicircle, and is formed at an angle close to approximately 90 degrees. On both sides in the width direction of the boundary portion with the end portion 121, stoppers 123 are integrally formed toward the inside. The stopper 123 constrains both sides of the end portion of the conductive band 20, and Misalignment is prevented. In addition, on both sides of the lower surface of the end 121, projections 124 are formed corresponding to the missing portions 113 provided at the end of the fixed piece 11. The height of the projection 124 is substantially equal to the plate thickness of the fixed piece 11. Further, a screw insertion hole 125 for fastening is opened at the end 121. In addition, in order to increase the mechanical strength of the end portion, a plurality of ribs 126 are formed on the outer surface of the end portion 121 across the boundary portion with the circular portion.
[0010]
The state in which the electric wire harness and the shield tube are fixed to the metal chassis using the grounding clamp 1 having this configuration is shown in the perspective view of FIG. 3, and the front view and the side view of FIGS. 4 (a) and 4 (b). The plurality of wire harnesses 3 are inserted into the shield tube 2. As described above, the shield tube 2 is formed by forming a conductive film by plating or coating a conductive material on the surface of a resin tube. The shield tube 2 is inserted between the circular portions 112 and 122 of the fixed piece 11 and the fastening piece 12 of the grounding clamp 1. Accordingly, the fastening piece 12 is bent and deformed to the fixed piece 11 side by utilizing the deformability of the hinge part 13, and the screw insertion hole 125 in the end part 111 of the fixed piece 11 from the screw insertion hole 125 in the end part 121 of the fastening piece 12. A screw 4 is inserted through 114, and the screw 4 is fastened to the chassis 5. By this fastening, the end portion 121 of the fastening piece 12 is brought into contact with the end portion 111 of the fixed piece 11 so that both pieces are integrated, and the shield tube 2 is sandwiched between the circular portions 112 and 122, thereby shielding the shield. The tube 2 is fixed to the chassis 5.
[0011]
In this fixed state, since the conductive band 20 is pressed against the outer peripheral surface of the shield tube 2, the shield tube 2 is electrically connected to the conductive band 20. Further, the end portions 111 and 121 of both the pieces 11 and 12 are brought into contact with each other, so that the protruding portion 124 provided on the end portion 121 of the fastening piece 12 is placed in the missing portion 113 of the end portion 111 of the fixed piece 11. Projected in the plate thickness direction. For this reason, the end edge 21 on the fixed piece side of the conductive band 20 extended to the top of the defect 113 is pressed by the projection 124 and deformed in the plate thickness direction, and its lower surface passes through the defect 113 and the chassis. 5 is brought into contact with the surface. As a result, the conductive band 20 is electrically connected to the chassis 5 on the outer surface, and as a result, the shield tube 2 is electrically connected to the chassis 5 through the conductive band 20.
[0012]
Therefore, in this grounding clamp, the conductive film on the surface of the shield tube 2 is grounded to the chassis 5 only by the conductive band 20 without passing through the main body portion 10 of the clamp. For this reason, it is not necessary to form the main body portion 10 with a conductive material or to form a conductive film on the surface thereof, and the main body portion 10, that is, the grounding clamp 1 can be formed by integral molding of the resin as described above. Become. Therefore, when manufacturing the clamp, it is only necessary to adhere the conductive band to the inner surface of the resin-molded main body, and the manufacturing process becomes extremely simple. Moreover, there is no possibility of poor electrical contact due to wear of the conductive plating.
[0013]
In the above embodiment, the conductive band 20 is bonded to the inner surface of the main body 10. However, the conductive band 20 is sandwiched in the width direction by the stoppers 115 and 123 provided on the fixing piece 11 and the fastening piece 12, respectively. If possible, the conductive band 20 may be simply fitted and supported on the main body 10. In the above embodiment, since the rib 126 is provided at the end of the fastening piece 12, a relatively large pressing force is generated on the protrusion 124 during fastening, and the conductive band 20 is applied to the surface of the chassis 5. It is possible to obtain a good electrical connection state by pressing strongly. However, it is not necessary to provide ribs as long as the required mechanical strength can be obtained by appropriately setting the plate thickness of the fixed piece 11.
[0014]
Here, in the said embodiment, although the defect | deletion part 113 is provided in the both sides of the width direction of the edge part 111 of the fixed piece 11, an opening is provided in the center part of the width direction, and this opening is provided in the edge part of a fastening piece. By providing a protrusion corresponding to the above, a part of the conductive band may be brought into contact with the chassis surface through this opening to make electrical connection.
[0015]
In the above-described embodiment, the case where the shield tube is circular has been described. However, the present invention can be applied even in the case of a square shape. In this case, the main body portion of the grounding clamp has the circular portion described above. Instead, a square part may be formed. Further, the fixing piece and the fastening piece may use a clip in addition to fastening with a screw. For example, a clip is provided at the end of the fastening piece, and the fastening piece is attached to the fixing piece by inserting a hole provided in the end of the fixing piece and engaging with a hole provided in the chassis. At the same time as the integration, the clamp itself may be fixed to the chassis.
[0016]
【The invention's effect】
As described above, the grounding clamp according to the present invention is formed of a resin material and is fixed to the chassis or the like in a state where the shield tube is sandwiched between the defect portion and the position facing the defect portion. When the clamp body is fixed to the chassis or the like, the conductive band extending along the clamping surface of the shield tube of the clamp body from the back side is provided by the protrusion. Since it is pressed and is reliably brought into contact with the chassis or the like through the defective portion, the shield tube is electrically connected to the chassis or the like through the conductive band, and is grounded. For this reason, it is not necessary to make the clamp main body part have a conductive structure, and it becomes possible to use the resin molded product as it is, and there is an effect that the number of manufacturing steps of the clamp can be reduced and the manufacturing can be easily performed.
[Brief description of the drawings]
FIG. 1 is a perspective view of a grounding clamp of the present invention.
2 is a front view and a side view of FIG. 1. FIG.
FIG. 3 is a perspective view of a state in which a shield tube is clamped.
4 is a front view and a side view of FIG. 3. FIG.
FIG. 5 is a perspective view of a conventional grounding clamp.
FIG. 6 is a perspective view of a shield tube clamped by a conventional grounding clamp.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Grounding clamp 2 Shield tube 3 Electric wire harness 4 Screw 5 Chassis 10 Clamp body part 11 Fixing piece 12 Fastening piece 20 Conductive belt 111 End part 112 Circular part 113 Deletion part 115 Stopper 121 End part 122 Circular part 123 Stopper 124 Protrusion part

Claims (2)

An electric wire harness is inserted inside, and a grounding clamp for fixing and supporting at least a conductive shield tube with a conductive surface on a conductive base, and electrically connecting the two, wherein the grounding clamp is a resin A clamp body portion integrally formed with a material and fixed to the conductive base in a state where the shield tube is sandwiched, and a conductive band extending along the clamping surface of the shield tube of the clamp body portion The clamp main body portion is provided with a defect portion for exposing the conductive band, and a protrusion disposed at a position facing the defect portion, and the clamp main body portion is provided on the conductive substrate. when secured, the protrusion causes the presses deform the conductive strip from the back side of the defect, to the conductive substrate wherein said conductive band through the defect Grounding clamp, characterized in that it is touch. The clamp body part is composed of a fixed piece and a fastening piece hinged to each other, and a conductive band that can be elastically deformed is affixed along the inner surface of the fixed piece and the fastening piece. A defect part is removed, and a fastening piece is provided with a protruding part protruding to the fixed piece side at a position facing the defect part, and the fastening piece is brought into contact with the conductive substrate side in the fastening state. The grounding clamp according to claim 1, wherein a piece is fastened to the conductive substrate .

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