JPH0623181U - Pin jack - Google Patents

Abstract

(57) [Abstract] [Purpose] The strength of the plate-shaped base of the grounding metal fitting is increased and it is suitable for automation of assembly, facilitating the assembly of the insulating bush to the grounding metal fitting, and preventing the displacement of the deformed position of the protruding terminal of each contact. To prevent. [Structure] The plate-like base portion 22 of the grounding metal fitting 21 is provided with ribs 26 having both side edges bent to the back side, engaging holes 27a are provided in the ribs, and engaging grooves 3 are provided on both sides of the insulating bush 31.
4 is provided with an elastic piece 35 integrally formed in a cantilever manner via
On the outer side of the elastic piece, there is provided an engaging projection 35a which is fitted into the engaging hole to prevent the insulating bush from being pulled out and locked to the ground fitting, and is inserted into the ground fitting and the plurality of tubular portions 25 to be assembled. The insulating bush and the upper and lower contacts 41 and 51 assembled to the insulating bush form the unit 20, and the insulating bush is provided with a fitting groove 33a.
5 has insertion pieces 44 and 54 formed in a bent shape at the base end thereof, and the insertion pieces are fitted into the fitting grooves from the back side, and the intermediate portion of the protruding terminal of the contact assembled to the upper insulating bush is located at the lower side. It is fitted in the engaging groove of the insulating bush.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a pin jack used by being attached to a receiving plate or the like provided in an electric device.

[0002]

[Prior art]

 As shown in FIGS. 22 and 23, a conventional pin jack includes a housing 1 in which an insulating substrate 3 and a plurality of cylindrical insulating bushes 4 are integrated, and a ground metal fitting is provided on the outer periphery of each insulating bush 4. The tubular portion 5a of No. 5 is fitted from the front side, and the insulating bush 4 in the lower tubular portion 5a is formed to be slightly shorter, so that the insulating bush 4 can be easily identified from the front side. 4 has a washer 9 of a different color, and the pressing plate 8 presses the flat base 5b of the grounding metal 5 from the front side, and the contact pieces 6a and 7a from the rear side to the locking groove 4a in the insulating bush 4. The upper and lower contacts 6 and 7 are assembled by press fitting, and the tips of the protruding terminals 6b and 7b of the contacts 6 and 7 protrude below the housing 1.

[0003]

[Problems to be solved by the device]

 However, in the conventional pin jack, since the base portion 5b of the ground metal fitting 5 has a flat plate shape, the flat base material 5b is easily deformed, and when the ground metal fitting 5 is supplied to the component feeder in the automatic assembly process. Moreover, not only can the parts not ride on each other at the flat base portion 5b to facilitate the assembly, but also because a plurality of insulating bushes 4 are integrated, it is difficult to assemble them into the grounding metal fitting 5. Since it is not easy, some parts are assembled on the housing 1 from the front side and some parts are assembled from the rear side, and the washer 9 needs to be assembled only inside the tubular portion 5a below the grounding metal 5. However, there was a drawback that it was not suitable for automation of assembly and high efficiency. Further, in the upper and lower contacts 6 and 7, the projecting terminals 6b and 7b projecting downward of the housing 1 are easily deformed, and in particular, since the projecting terminals 6b of the upper contacts 6 have a long leg length, the positioning and holding thereof Is insufficient, and there is a problem that the deformed position of the protruding terminal 6b is likely to be displaced.

An object of the present invention is to provide sufficient strength to the base portion of the grounding metal fitting and prevent the parts from riding on each other, thereby facilitating the assembly of the insulating bush to the grounding metal fitting, and assembling or assembling the parts. An object of the present invention is to provide a pin jack that can be carried out from only one direction, requires no washers, and that does not cause deformation or displacement of the protruding terminals of each contact.

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the gist of the present invention according to claim 1 is that an earth metal fitting integrally provided with a ground terminal protruding from a plate-like base portion and a plurality of tubular portions is assembled to the housing from the rear side. And an insulating bush that is inserted into the plurality of tubular portions from the back side to be assembled, and a contact that is attached to the insulating bush from the back side and has a contact piece. The pin jack according to claim 2 is characterized in that the pin jack is provided with a rib whose both side edges are bent toward the back side, and the present invention according to claim 2 is the pin jack according to claim 1. A part of the insulating bush is provided with elastic pieces integrally formed in a cantilever shape on both sides of the insulating bush with an engaging groove interposed. The insulation bush to the above-mentioned ground metal fitting. Characterized by providing an engaging protrusion for locking and stop.

Further, the gist of the present invention according to claim 3 is that an earth metal fitting having a plurality of tubular portions and assembled to a housing, and a plurality of tubular portions are inserted from the back side and assembled. A plurality of insulating bushes and a contact that is assembled to the insulating bush from the back side and integrally has a contact piece are provided, and the plurality of insulating bushes are individually molded with insulating materials of different colors. The pin jack is characterized in that the plurality of insulating bushes can be identified by color, and the gist of the present invention according to claim 4 is that a ground terminal and a plurality of cylindrical portions projecting from a plate-shaped base are provided. A housing unit with an open rear side is formed by integrally forming an earth metal fitting, an insulating bush inserted into the plurality of tubular parts and assembled, and a contact assembled to the insulating bush. A pin jack is characterized in that the plate-shaped base is housed in a portion and the assembly unit is assembled to the housing.

Further, the gist of the present invention according to claim 5 is that a grounding terminal projecting from a plate-shaped base and a plurality of cylindrical parts are mounted on the housing from the back side, and An insulating bush, which is inserted into the cylindrical portion of the insulating member from the back side to be assembled, and a contact having a contact piece, which is assembled to the insulating bush from the rear side, and the insulating bush is provided with a fitting groove. The pin jack characterized in that the protruding terminal has a bent insertion piece at a base end thereof, and the insertion piece is inserted into the insertion groove from the rear side, and the present invention according to claim 6, The pin jack according to claim 5, wherein the insulating bush is provided with an engaging groove, and an intermediate portion of a protruding terminal of a contact assembled to one insulating bush of the plurality of insulating bushes is connected to the other insulating bush. Fit into the engagement groove It is characterized in that it is inserted and positioned and held.

[0007]

[Action]

 In the pin jack according to claim 1 of the present invention, the plate-shaped base portion of the grounding metal is reinforced by forming ribs with both side edges bent toward the back side. When the ground metal fittings are fed on the component feeder with the back side facing upward, the components do not ride on top of each other, and in the pin jack according to claim 2, the ribs of the ground metal fittings are provided with engaging holes, and both sides of the insulating bush are provided. Is provided with an elastic piece integrally formed in a cantilever shape through an engaging groove, and an engaging protrusion that is fitted into the engaging hole on the outer side of the elastic piece to prevent the insulating bush from being pulled out from the ground metal fitting and to be locked. It is easy to assemble the insulation bush to the grounding metal fitting by providing the above, and in the pin jack according to claim 3, by forming a plurality of insulation bushes individually with insulating materials of different colors, In different colors The plurality of insulating bushes can be identified with each other, and in the pin jack according to claim 4, a grounding terminal integrally provided with a grounding terminal and a plurality of cylindrical portions projecting from a plate-shaped base, and a plurality of cylindrical The assembly unit is formed by the insulation bush inserted into the housing and assembled, and the contacts assembled in the insulation bush, and the housing unit is housed by housing the plate-shaped base in the housing housing of which the rear side is open. It is easy to assemble, highly efficient and easy to automate.

Further, in the pin jack according to a fifth aspect of the present invention, the insulating bush is provided with a fitting groove, and the base end of the protruding terminal has a bent insert piece, and the insert piece is inserted into the insert groove on the rear surface side. Since the protruding terminal is prevented from being deformed by being inserted from the above, the pin jack according to claim 6, wherein the insulating bush is provided with an engaging groove, and one of the plurality of insulating bushes is provided with one engaging bush. The middle portion of the protruding terminal of the assembled contact is fitted into the engaging groove of the other insulating bush to position and hold it.

[0009]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings by taking a four-series pin jack having four fitting portions to which mating pin plugs are fitted as an example. 1 is a rear view showing a pin jack according to an embodiment of the present invention, FIG. 2 is a side view thereof, FIG. 3 is a partially cutaway side view showing an assembly unit assembled in a housing, and FIG. 4 is a rear view thereof. .

In the pin jack according to the embodiment of the present invention, an earth terminal 24 and two tubular portions 25 are integrally projectingly provided on a plate-like base portion 22 of a grounding metal fitting 21 so as to correspond to each tubular portion 25. The insulation bush 31 is inserted and assembled, and the contacts 41 and 51 integrally having the contact pieces 42 and 52 are assembled to the upper and lower insulation bushes 31 and 31, respectively, and the assembly unit 20 shown in FIGS. The plate-shaped bases 22, 22 are respectively housed in the left and right housings 19, 19 of the housing 11 which are formed and opened on the back side, and the assembly unit 20 is assembled in the housing 11.

Further, in this pin jack, both side edges of the plate-like base portion 22 of the grounding metal fitting 21 are bent toward the back side to form ribs 26, and the plate-like base portion 22 is reinforced by the ribs 26, and the respective ribs are reinforced. The ribs 26 of the metal fitting 21 are provided with engaging holes 27a (see FIG. 3) at four positions, and elastic pieces 35 integrally formed in a cantilever manner on both sides of the insulating bush 31 via engaging grooves 34. The engaging protrusion 35a provided on the outer side of the elastic piece 35 is fitted into the engaging hole 27a so that the insulating bush 31 is prevented from being pulled out of the grounding metal fitting 21 and is locked. The upper and lower insulating bushes 31, 31 are separately formed integrally with each other by a material, and the upper and lower insulating bushes 31, 31 can be identified by the different colors.

Further, in this pin jack, the intermediate portion of the protruding terminal 45 of the contact 41 assembled to the upper insulating bush 31 among the four insulating bushes 31 is fitted into the engaging groove 34 of the lower insulating bush 31. To prevent the projecting terminal 45 from being deformed and displaced, the insulating bush 31 is provided with a fitting groove 33a, and the projecting terminals 45 and 55 have bent insertion pieces 44 and 54 at their base ends. The insertion pieces 44 and 54 are fitted into the fitting grooves 33a and 33a of the corresponding insulating bushes 31 and 31 from the rear side to further prevent deformation of the protruding terminals 45 and 55 from being displaced.

5 is a rear view showing the housing, FIG. 6 is a plan view, FIG. 7 is a view taken along the line AA of FIG. 5, and FIG. 8 is a view taken along the line BB of FIG. The housing 11 has a symmetrical shape vertically and horizontally by a front plate 12 and upper and lower holding plates 13 and 13 which are integrally provided on four sides of the front plate 12 and left and right holding plates 15 and 15 which are orthogonal to the holding plates 13 and 13 and a partition portion 17. It has two left and right storage portions 19, 19 formed in the above. The front plate 12 has a total of four through holes 12a, two through which the tubular portion 25 of the grounding tool 21 penetrates, at a location corresponding to each of the accommodating portions 19, 19, and the two through holes 12a, A small protrusion 12b is provided on the inner surface side of the center between the 12a.

Each of the upper and lower holding plates 13, 13 is a set of three parallel slit-shaped grounding terminal engaging grooves 13 a and protruding terminal engaging grooves 13 b, 13 b arranged at equal intervals on the left and right sides thereof. It is provided so as to correspond to each of the accommodating portions 19 and to extend straight. The left and right holding plates 15 and 15 are composed of upper and lower flat plate portions 15a having a smaller depth than the upper and lower holding plates 13 and 13 and a central semicircular arc plate portion 15b. The locking projections 1 are formed on the inner surfaces of the upper and lower flat plate portions 15a. 5c is provided, and a cutout 15d (see FIG. 8) is formed so as to extend over a part of the upper and lower flat plate portions 15a and the semi-circular plate portion 15b.

The partition portion 17 is provided on the inner surface of the center of the front plate 12 so as to project from a central projection 18 composed of a columnar body 18 a and an overhanging body 18 b connected to the upper and lower sides of the cylindrical body 18 a. The left and right partition plates 17a, 17a provided vertically on the inner surface of the face plate 12 are provided, and a mounting hole 18c into which a mounting bolt (not shown) is inserted is provided at the center of the central protrusion 18, and each left and right partition plate 17a is provided. A locking projection 17c having the same shape as the locking projection 15c is provided at a position corresponding to the locking projection 15c of the flat plate portion 15a.

FIG. 9 is a side view showing a part of the grounding metal part cut away, FIG. 10 is a rear view, and FIG. 11 is a bottom view. The grounding metal fitting 21 includes a semicircular recess 12c and a recess 22a adapted to the outer periphery of the cylindrical body 18a of the central protrusion 18 on both left and right sides, and a symmetrical plate-shaped base 22 having a small circular hole 22b in the center, and a housing. A position adjusting plate portion 23 formed by bending the lower end of the plate-like base portion 22 accommodated in the portion 19 toward the rear side, and a position adjusting plate portion 23 that is bent further downward at a substantially right angle from the widthwise center of the position adjusting plate portion 23 and protrudes. The ground terminal 24, the two cylindrical portions 25 that have an inward flange 25a at the tip and are formed symmetrically by projecting from the plate-shaped base portion 22 to the front side, and both edges of the plate-shaped base portion 22 are full length. It is integrally provided with a rib 26 formed in a symmetrical arrangement by being bent to the back side at a substantially right angle.

Further, the grounding metal fitting 21 has a rectangular engaging hole 27 a formed in each of the engaging protrusions 27 projecting symmetrically at four positions of the rib 26, and both edges of the engaging protrusion 27 are inward. A guide piece 27b is formed by bending, and the tubular portion 25 is inserted into the through hole 12a of the front plate 12, the plate-shaped base portion 22 is accommodated in the accommodation portion 19, and the small protrusion 12b is inserted into the small circular hole 22b. Then, the rear end surface of the rib 26 is engaged with the locking projections 15c and 17c to prevent the ribs from coming off, and is assembled to the housing 11.

FIG. 12 is a front view showing the insulating bush, FIG. 13 is a side view, FIG. 14 is a rear view, and FIG. 15 is a view taken along the line CC in FIG. The insulating bush 31 has a symmetrical shape and is provided with an insertion portion 32 that is inserted into the tubular portion 25 of the grounding metal fitting 21 and an engagement portion 33 that is integrally molded with the insertion portion 32. There is a plug insertion hole 31a penetrating in a core arrangement, and locking grooves 31b continuous from the side of the engaging portion 33 to an intermediate position are provided in the plug insertion hole 31a. The engaging portion 33 includes left and right engaging grooves 34, elastic pieces 35 symmetrically arranged through the engaging grooves 34, and fitting portions formed symmetrically on the upper and lower sides of the plug insertion hole 31a. When the insertion protrusion 32a is provided on the outer surface side of each elastic piece 35 and the insertion portion 32 is inserted into the tubular portion 25, the engagement protrusion 35a of the elastic piece 35 is provided with the engagement hole 27a. It is fitted into the grounding metal fitting 21 and is attached to the grounding metal fitting 21 without being pulled out.

The upper insulating bush 31 is entirely white, and the lower insulating bush 31 is entirely colored in a single color red. Both elastic pieces 35 are positioned and guided by corresponding guide pieces 27b. However, when the insertion portion 32 is inserted into the tubular portion 25 of the grounding metal fitting 21 and assembled, it can be clearly identified by the difference in the upper and lower colors when viewed from the front outside.

FIGS. 16, 17 and 18 are front views, side views and plan views showing the upper contacts, respectively, and FIGS. 19, 20 and 21 are front views, side views and plan views showing the lower contacts, respectively. Both of these contacts 41 and 51 are shown in the drawing in a substantially line-symmetrical relationship with each other except that the legs of the protruding terminals 45 and 55 are different in length. The upper contact 41 includes a fork-shaped contact piece 42, and a position adjustment piece 43 and an insertion piece formed by bending a fork-shaped contact piece 42 at a base end portion thereof into a substantially right angle and a lateral direction at a lower portion thereof and bending at a substantially right angle to a front portion. 44 and a projecting terminal 45 that is bent downward at a substantially right angle at the side end of the insertion piece 44 and projects downward. A protruding portion 45 of the projecting terminal 45 has a V-shaped bent portion 46. The projection terminal 45 is positioned and held by inserting the middle portion of the projection terminal 45 into the engagement groove 34 of the lower insulating bush 31.

In addition, the upper contact 41 is provided with locking protrusions 47 on both sides of the base end of the contact piece 42, and a portion near the base end of the contact piece 42, a portion extending between the position adjustment piece 43 and the insertion piece 44. Reinforcing strips 48 are provided near the base end of the protruding terminal 45, and the position of the protruding terminal 45 with respect to the contact piece 42 is adjusted by the position adjusting piece 43, and the insertion piece 44 is inserted into the fitting groove 33a. The deformation of the protruding terminal 45 is prevented. The base of the contact piece 42 is provided with a semi-circular projecting piece 49 formed by cutting and raising in the opposite direction to the position adjusting piece 43, and the semi-circular projecting piece 49 and the position adjusting piece 43 are used for the plug insertion hole 31a of the insulating bush 31. However, it is almost closed at the position on the back side.

The lower contact 51 has a contact piece 52, a position adjusting piece 53, an inserting piece 54, a projecting terminal 55, a bent portion 56, a locking projection 57, and the like. Except for being shortened, it has a line-symmetrical relationship with the above-mentioned upper contact 41, so that detailed description thereof will be omitted.

The assembly sequence of the pin jack according to the above embodiment will be described. Individual insulating bushes 31 are inserted into the upper and lower cylindrical portions 25, 25 of the respective earth fittings 21 from the back side, and the engaging projections 35a are fitted into the engaging holes 27a to prevent the insulating bushes 31 from being pulled out. 21. Insert the contact pieces 42, 52 into the plug insertion hole 31a and the locking groove 31b of the insulating bush 31 from the back side and prevent the contact projections 47, 57 from pulling out the contacts 41, 51. Assemble to each corresponding insulation bush 31, 31. At this time, the protruding terminals 45, 45 of the contacts 41, 41 inserted in the upper insulating bushes 31, 31 are press-fitted into the engaging grooves 34, 34 of the corresponding insulating bushes 31, 31 directly below to hold them in position.

The grounding metal fitting 21 assembled in this way, the two insulating bushes 31, 31, and the two contacts 41, 51 form an assembly unit 20, and the locking projections 15 c, 17 c of the housing 11 have ribs 26, 26. The plate-shaped base portion 22 is pushed into the accommodating portion 19 so as to be retained until it is engaged with the rear end face of the, and the intermediate portion of the ground terminal 24 and the projecting terminals 45, 55 is engaged with the corresponding engaging groove 13a, 13b, 13b, and the two sets of the assembly units 20 are assembled to the housing 11 to complete the assembly of the quadruple-type pin jack. The pin jack has a bolt that is inserted into the mounting hole 18c of the central protrusion 18 and is screwed to a receiving plate or the like provided in an electric device (not shown).

According to the above-described embodiment of the present invention, the plate-shaped base portion 22 is pushed into the accommodation portion 19 to the position where the locking projections 15c and 17c of the housing 11 are engaged with the rear end surfaces of the ribs 26 and 26. Since the assembly unit 20 is stopped and housed and the assembly unit 20 is assembled to the housing 11, the assembly is efficient and the assembly is easy to automate. The present invention is not limited to the above embodiment, but can be applied to a dual pin jack or six or more pin jacks. Of course, it can also be applied to a vertical triple type, and various modifications can be made without departing from the scope of the invention.

[0026]

[Effect of device]

 The present invention is configured as described above, and in the pin jack according to claim 1, the plate-shaped base portion of the grounding metal is provided with ribs formed by bending both end edges to the back side, so that the plate-shaped base portion is The pin jack according to claim 2, wherein the ground jack is provided with an engaging hole, and the insulating bush is provided with insulation holes. On both sides of the elastic piece, elastic pieces integrally formed in a cantilever shape through engaging grooves are provided, and the outer side of the elastic piece is fitted into the engaging hole to prevent the insulating bush from being pulled out from the earth metal fitting and locked. By providing the engaging projections, it is extremely easy to assemble the insulating bush to the ground fitting.

In the pin jack according to claim 3 of the present invention, a plurality of insulating bushes are individually molded with insulating materials of different colors, and the plurality of insulating bushes can be identified by the different colors. There is an advantage that all the insulating bushes can be unified into the same shape and the insulating bushes can be easily assembled. In the pin jack according to claim 4, the ground terminal and the plurality of cylindrical portions projecting from the plate-shaped base are integrated. The grounding metal fitting, the insulation bush inserted into multiple cylindrical parts and assembled, and the contacts assembled to the insulation bush form an assembled unit. By accommodating the parts and assembling the assembling unit to the housing, the assembling is easy, the efficiency is high, and the automation is easy.

Further, in the pin jack according to claim 5 of the present invention, the insulating bush is provided with a fitting groove, and the base end of the protruding terminal has a bent insertion piece, and the insertion piece is fitted with the fitting groove. It is possible to surely prevent the deformed position of the projecting terminal from being displaced by being fitted into the back surface of the pin jack according to claim 6. By inserting the middle part of the protruding terminal of the contact assembled in one insulating bush into the engaging groove of the other insulating bush and holding it in position, it is possible to further prevent deformation position displacement of the protruding terminal. It has an excellent effect.

[Brief description of drawings]

FIG. 1 is a rear view showing a pin jack according to an embodiment of the present invention.

FIG. 2 is a side view showing a pin jack according to an embodiment of the present invention.

FIG. 3 is a partially cutaway side view showing an assembly unit assembled in a housing of a pin jack according to an embodiment of the present invention.

FIG. 4 is a rear view showing an assembly unit of a pin jack according to an embodiment of the present invention.

FIG. 5 is a rear view showing a housing according to an embodiment of the present invention.

FIG. 6 is a plan view showing a housing according to an embodiment of the present invention.

FIG. 7 is a view on arrow AA of FIG.

FIG. 8 is a view taken along the line BB of FIG.

FIG. 9 is a side view showing a partially broken grounding fitting according to an embodiment of the present invention.

FIG. 10 is a rear view showing an earth metal fitting according to an embodiment of the present invention.

FIG. 11 is a bottom view showing an earth metal fitting according to an embodiment of the present invention.

FIG. 12 is a front view showing an insulating bush according to an embodiment of the present invention.

FIG. 13 is a side view showing an insulating bush according to an embodiment of the present invention.

FIG. 14 is a rear view showing an insulating bush according to an embodiment of the present invention.

15 is a view taken along the line C-C of FIG.

FIG. 16 is a front view showing an upper contact according to the embodiment of the present invention.

FIG. 17 is a side view showing an upper contact according to an embodiment of the present invention.

FIG. 18 is a plan view showing an upper contact according to an embodiment of the present invention.

FIG. 19 is a front view showing a lower contact according to the embodiment of the present invention.

FIG. 20 is a side view showing a lower contact according to an embodiment of the present invention.

FIG. 21 is a plan view showing a lower contact according to the embodiment of the present invention.

FIG. 22 is a rear view showing a conventional pin jack.

FIG. 23 is a cross-sectional view showing a conventional pin jack.

[Explanation of symbols]

 Reference Signs List 11 housing 12 front plate 12a through hole 12c semicircular recess 13 holding plate 13a ground terminal engaging groove 13b protruding terminal engaging groove 15 holding plate 15a flat plate portion 15c locking protrusion 17 partition portion 17a partition plate 17c locking protrusion 18 Central protrusion 18a Cylindrical body 19 Housing portion 20 Assembly unit 21 Grounding metal fitting 22 Plate-shaped base portion 24 Grounding terminal 26 Rib 27 Engagement protrusion piece 27a Engagement hole 27b Guide piece 31 Insulation bush 31a Plug insertion hole 31b Engagement groove 32 Insertion portion 33 Engagement portion 33a Fitting groove 34 Engagement groove 35 Elastic piece 35a Engagement protrusion 41,51 Contact 42,52 Contact piece 43,53 Position adjustment piece 44,54 Insertion piece 45,55 Projection terminal 46,56 Bent portion

Claims (6)

[Scope of utility model registration request] 1. A grounding metal fitting integrally provided with a grounding terminal and a plurality of cylindrical portions projecting from a plate-like base and assembled to the housing from the rear side, and a grounding metal fitting inserted into the plurality of cylindrical portions from the rear side. An insulating bush to be assembled and a contact having a contact piece assembled from the back side to the insulating bush are provided, and a plate-shaped base portion of the earth metal fitting is provided with ribs formed by bending both end edges to the back side. A pin jack characterized by that. 2. The pin jack according to claim 1, wherein at least a part of the rib is provided with an engagement hole, and an engagement groove is provided on both sides of the insulating bush so as to be integrally formed in a cantilever shape. A pin jack, comprising: a piece, and an engagement protrusion that is provided on the outer side of the elastic piece and that is fitted into the engagement hole to prevent the insulating bush from being pulled out from the grounding metal and to be locked. 3. A grounding metal fitting having a plurality of tubular parts to be assembled to a housing, a plurality of insulating bushes inserted into the plurality of tubular parts from the back side and assembled, and a back side to the insulating bushes. Characterized in that the plurality of insulating bushes are individually molded with insulating materials of different colors, and the plurality of insulating bushes can be identified by the different colors. Let's say pin jack. 4. An earth metal fitting integrally having an earth terminal projecting from a plate-like base and a plurality of tubular parts, an insulating bush inserted into the plurality of tubular parts and assembled, and an insulating bush. Form an assembled unit with the attached contacts,
A pin jack characterized in that the plate-shaped base is housed in a housing part of the housing having an opening on the back side, and the assembly unit is assembled to the housing. 5. A grounding metal fitting having a grounding terminal projecting from a plate-shaped base and a plurality of tubular parts, which is assembled to the housing from the back side, and an assembly fitting by inserting the plurality of tubular parts from the back side. An insulating bush and a contact having a contact piece assembled to the insulating bush from the back side, a fitting groove is provided in the insulating bush, and a bent insertion piece is provided at the base end of the protruding terminal. Then, the pin jack in which the insertion piece is fitted into the fitting groove from the back side. 6. The pin jack according to claim 5, wherein the insulating bush is provided with an engaging groove, and the intermediate portion of the protruding terminal of the contact assembled to one insulating bush of the plurality of insulating bushes is the other. The pin jack is fitted in the engaging groove of the insulating bush and positioned and held.