# Patent

## Title
Socket having a connection fitting with a divided spring member

## Abstract

A socket includes: a base; a connection fitting including a bracket and a spring member, configured to form pressure springs by dividing the spring member into two in a width direction by a slit provided to the spring member, and assembled to an upper surface of the base; and a case cover configured to fit to the base and to cover the connection fitting. The pressure springs of the spring member are pressed and elastically deformed by an operation driver inserted through an operation hole provided to the case cover, to sandwich between the bracket and the pressure springs a lead inserted through an insertion hole provided to the case cover. A guide partition wall configured to engage with the slit of the spring member is integrally molded with an inner surface of the case cover.

## Background
CROSS-REFERENCE TO RELATED APPLICATION
This application is based on Japanese Patent Application No. 2015-182121 filed with the Japan Patent Office on Sep. 15, 2015, the entire contents of which are incorporated herein by reference.
FIELD
The present invention relates to a socket and, more particularly, relates to a socket which connects leads by using an operation driver.
BACKGROUND
Conventionally, a socket which connects leads by using an operation driver is formed by, for example, assembling in a housing a connection fitting including a bracket and a spring member. Further, there is a socket which causes the operation driver inserted in the housing to elastically deform the spring member to sandwich the leads between the bracket and the spring member (see German Patent No. 102009004513).
Furthermore, there is a case where the socket sandwiches two leads between a pair of pressure springs formed by dividing the spring member in two in a width direction, and the bracket to extract two signals from one circuit.
However, there is a problem that the socket cannot accurately position the two leads between a pair of neighboring pressure springs and the bracket, and therefore is likely to cause connection failure based on erroneous insertion of the leads.
SUMMARY
In view of the problem, an object of the present invention is to provide a socket which does not cause connection failure.
To solve the above problem, a socket according to the present invention is a socket including: a base; a connection fitting including a bracket and a spring member, configured to form a pressure spring by dividing the spring member into two in a width direction by a slit provided to the spring member and assembled to an upper surface of the base; and a case cover configured to fit to the base and to cover the connection fitting, the pressure spring of the spring member being pressed and elastically deformed by an operation driver inserted through an operation hole provided to the case cover, to sandwich between the bracket and the pressure spring a lead inserted through an insertion hole provided to the case cover, in which a guide partition wall configured to engage with the slit of the spring member is integrally molded with an inner surface of the case cover.
According to the present invention, the guide partition wall partitions a pair of neighboring pressure springs, so that it is possible to insert two leads along the guide partition wall. Consequently, it is possible to provide a socket which prevents erroneous insertion of the leads, improves assembly precision and consequently does not cause connection failure.
According to the embodiment of the present invention, the guide partition wall is bridged between and integrally molded with a ceiling surface and an inside surface of the case cover.
According to the embodiment, the guide partition wall is bridged between the ceiling surface and the inside surface of the case cover, so that it is possible to provide the guide partition wall of high support strength. Hence, even when the operation driver is erroneously inserted through an operation hole of the case cover, the guide partition wall is not broken, and broken pieces are not produced. As a result, it is possible to provide a socket which does not cause connection failure caused by the broken pieces.
According to another embodiment of the present invention, a notch configured to engage with a protrusion protruded from an upper surface of the base may be formed at a lower end rim of the guide partition wall.
According to the embodiment, there is an advantage that support strength of the guide partition wall further increases, and not only connection failure does not occur but also rigidity of the entire case cover increases, so that it is possible to provide a socket adopting a firm structure.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating a first embodiment of a socket according to the present invention;
FIG. 2 is a plan view of the socket shown in FIG. 1;
FIG. 3 is a partial front view of the socket shown in FIG. 1;
FIG. 4 is a vertical sectional view of the socket shown in FIG. 1;
FIG. 5 is a vertical sectional view cut at a different position of the socket shown in FIG. 1;
FIG. 6 is an exploded perspective view of the socket shown in FIG. 1;
FIG. 7 is a perspective view illustrating a state where a case cover is detached from the socket shown in FIG. 1;
FIG. 8 is a vertical sectional view of the socket shown in FIG. 7;
FIG. 9 is a left side view for explaining a method for using the socket shown in FIG. 1;
FIG. 10 is a vertical sectional view of the socket shown in FIG. 9;
FIG. 11 is a perspective view illustrating a second embodiment of a socket according to the present invention;
FIG. 12 is a plan view of the socket shown in FIG. 11;
FIG. 13 is a partial front view of the socket shown in FIG. 1;
FIG. 14 is an exploded perspective view of the socket shown in FIG. 1;
FIG. 15 is an explanatory view for explaining a method for analyzing an internal stress;
FIG. 16 is an explanatory view for explaining a method for analyzing an internal stress; and
FIG. 17 is a stress distribution view illustrating an analysis result.



DETAILED DESCRIPTION
Embodiments of a socket according to the present invention will be described with reference to accompanying drawings of FIGS. 1 to 14.
The socket according to a first embodiment is formed by a base 10, a connection fitting 20 and a case cover 40 as shown in the accompanying drawings of FIGS. 1 to 10.
As shown in FIG. 6, a seating 11 is protruded from an upper surface of the base 10 to form an annular step 12. A connection hole 13 is provided in an upper surface 11a which is one step lower in the upper surface of the seating 11. Further, a support protrusion 14 is protruded at a rim of an upper surface 11b which is one step higher in the upper surface of the seating 11. Furthermore, a position restricting protrusion 15 is integrally molded with a nearly center of the upper surface 11b. The position restricting protrusion 15 includes a position restricting tapered surface 16 at an upper end of the position restricting protrusion 15. Further, engagement claws 17 and 17 are protruded along a longitudinal direction of the seating 11 and on opposing outside surfaces.
In addition, in the embodiment, the position restricting protrusion 15 is integrally molded with the base 10, and the connection fitting 20 described below is assembled to the base 10. Hence, precision to position the connection fitting 20 is high, and an assembly error is little. As a result, when an operation driver (not shown) presses pressure springs 35 of the connection fitting 20, a pressing position does not vary, so that it is possible to effectively prevent occurrence of plastic deformation.
Particularly, the position restricting tapered surface 16 has an inclined angle which can come into planar contact with the pressure springs 35 when the pressure springs 35 of the connection fitting 20 described below elastically deform. Consequently, it is possible to effectively prevent plastic deformation of the pressure springs 35.
As shown in FIG. 6, the connection fitting 20 is formed by a bracket 21 and a spring member 30 whose sectional shape is a nearly V shape.
A retaining portion 22 is formed at one side of the bracket 21 provided with a through-hole 21a by bending a conductive metal plate by way of press working, and a caulked portion 23, a bottom portion 24 and a pressure contact portion 25 are formed at the other side.
The retaining portion 22 has a shape which can retain leads which are not shown by way of caulking work. Further, the caulked portion 23 is formed by having a plurality of caulking projections 26 project from a surface of the caulked portion 23, and a square fitting hole 27 is formed in the bottom portion 24. Furthermore, a pair of pressure contact receiving portions 29 and 29 are formed by dividing the pressure contact portion 25 into two by a slit 28 formed at a free end of the pressure contact portion 25.
The spring member 30 is bent in a nearly V shape, and has pluralities of caulking small holes 32 and caulking large holes 33 at the caulked portion 31 at one side of the spring member 30. Further, the spring member 30 has a slit 34 at a free end which elastically deforms at the other side of the spring member 30 to form a pair of pressure springs 35 and 35.
Furthermore, by caulking and fixing the caulking small holes 32 and the caulking large holes 33 of the spring member 30 to the caulking projections 26 and 26 of the bracket 21, leading end portions of the pressure springs 35 and 35 of the spring member 30 come into pressure contact with the pressure contact receiving portions 29 and 29 of the bracket 21.
Hence, the fitting hole 27 provided to the bottom portion 24 of the bracket 21 is fitted to and assembled to the position restricting protrusion 15 of the base 10. Further, leads which are not shown and are inserted from a lower side via the connection hole 13 of the base 10 are caulked and fixed to and are electrically connected to the retaining portion 22 of the bracket 21.
As shown in FIG. 4, the case cover 40 has a box shape which can fit to the annular step 12 of the base 10, and has a step shape including a step 41 at a single side of an upper surface of the box shape. Further, at a position corresponding to an upper end surface of the support protrusion 14 of the base 10 on an upper surface of the step 41, a recessed portion 42 is formed. Furthermore, at a bottom surface of the recessed portion 42, a through-hole 43 (FIG. 5) continuing to the through-hole 21a of the bracket 21 is formed. Hence, the bracket 21 can be electrically connected to the bracket 21 of another neighboring socket (not shown) via the through-hole 43 of the case cover 40.
Further, at a position corresponding to an intermediate area of the pressure springs 35 on the upper surface except the step 41, the case cover 40 has an operation hole 44 in which the operation driver which is not shown can be inserted. Furthermore, at a position corresponding to free ends of the pressure springs 35, insertion holes 45 in which leads can be inserted are formed. At an opening rim of each insertion hole 45, a chamfered portion 45a which makes it easy to insert leads is formed.
Further, at a corner of the step 41, a guide notch 46 having substantially a semi-arc surface is formed to guide the operation driver which is inserted in the operation hole 44.
Furthermore, as shown in FIGS. 4 and 5, the case cover 40 is integrally molded with a guide partition wall 47 to bridge the guide partition wall 47 between a ceiling surface and an inside surface of the case cover 40. The guide partition wall 47 may engage with the slit 28 of the bracket 21 and the slit 34 of the spring member 30. Further, the guide partition wall 47 includes at a lower end rim of the guide partition wall 47 a notch 48 (FIG. 5) which engages with the position restricting protrusion 15 of the base 10.
Furthermore, the case cover 40 includes engagement holes 49 (FIG. 6) which engage with the engagement claws 17 of the base 10 in opposing side surfaces.
Still further, by fitting the case cover 40 to the annular step 12 of the base 10, the engagement holes 49 of the case cover 40 engage with and are integrally formed with the engagement claws 17 of the base 10 (FIG. 1). Thus, the guide partition wall 47 of the case cover 40 engages with the slit 28 of the bracket 21 and the slit 34 of the spring member 30 (FIG. 4). Further, the notch 48 of the guide partition wall 47 engages with the position restricting protrusion 15 of the base 10 to partition the pressure springs 35 and 35.
When the socket is connected with a lead, as shown in FIG. 10, an operation driver 50 is inserted in the operation hole 44 to press the intermediate area of the pressure springs 35 and push down the pressure springs 35. Subsequently, the lead inserted through the insertion hole 45 is positioned between the leading end portions of the pressure springs 35 and the pressure contact receiving portions 29. Then, when the operation driver 50 is pulled, the pressure springs 35 are elastically restored, and the leading end portions of the pressure springs 35 and the pressure contact receiving portions 29 sandwich the lead.
Further, when the lead is detached, the operation driver 50 is inserted in the operation hole 44 to press the intermediate area of the pressure springs 35 and push down the pressure springs 35, so that it is possible to detach the lead.
According to the embodiment, when the operation driver 50 pushes down the pressure springs 35, the positions of the pressure springs 35 are restricted by the position restricting tapered surface 16 of the position restricting protrusion 15. Consequently, it is possible to prevent plastic deformation of the pressure springs 35.
A socket according to a second embodiment is substantially the same as that of the first embodiment as shown in FIGS. 11 to 14, and differs from the first embodiment in that a guide notch 46 provided to a step 41 of a case cover 40 is formed by a pair of flat and triangular tapered surfaces.
The guide notch 46 is formed by a pair of flat and triangular tapered surfaces. Consequently, by inserting an operation driver (not shown) along the guide notch 46, it is easy to position the operation driver. As a result, the operation driver can accurately and quickly operate the pressure springs 35.
Particularly when the operation driver is inserted along the guide notch 46, spring forces of the pressure springs 35 work on the operation driver. Hence, a retaining state of the operation driver stabilizes.
Further, placing the operation driver in direct contact with a corner of the case cover 40 without providing the guide notch 46 wears away the corner of the case cover 40. However, by providing the guide notch 46, the operation driver comes into linear contact with the guide notch 46. Consequently, there is an advantage that the case cover 40 is hardly worn away.
The other components are the same as those of the first embodiment and therefore the same components will be assigned the same reference numerals and will not be described.
EXAMPLE 1
A stress distribution was analyzed in case where, as shown in FIGS. 15 and 16, an intermediate area of pressure springs 35 of a spring member 30 according to the above embodiments was pushed down by an operation driver 50 and was elastically deformed. FIG. 17 illustrates an analysis result.
As is clear from FIG. 17, it was found that an internal stress concentrates at a flexing portion 36 of the spring member 30, and, more particularly, a side of a caulked portion 31 of the flexing portion 36.
In addition, as shown in FIG. 17, in the above embodiments, a position restricting tapered surface 16 is provided such that the pressure springs 35 of the spring member 30 come into contact with the position restricting tapered surface 16 of a position restricting protrusion 15 in an elastic deformation area. Consequently, it is possible to prevent plastic deformation of the pressure springs 35.
The socket according to the present invention is not limited to the above-described socket, and is applicable to a socket which can connect four leads.

## Claims

1. A socket comprising:
a base;
a connection fitting including a bracket and a spring member, configured to form a pressure spring by dividing the spring member into two in a width direction by a slit provided to the spring member, and assembled to an upper surface of the base; and
a case cover configured to fit to the base and to cover the connection fitting,
the pressure spring of the spring member being pressed and elastically deformed by an operation driver inserted through an operation hole provided to the case cover, to sandwich between the bracket and the pressure spring, a lead inserted through an insertion hole provided to the case cover,
wherein
a guide partition wall configured to engage with the slit of the spring member is integrally molded with an inner surface of the case cover.

2. The socket according to claim 1, wherein the guide partition wall is bridged between and integrally molded with a ceiling surface and an inside surface of the case cover.

3. The socket according to claim 1, wherein a notch configured to engage with a protrusion protruded from the upper surface of the base is formed at a lower end rim of the guide partition wall.

4. The socket according to claim 2, wherein a notch configured to engage with a protrusion protruded from the upper surface of the base is formed at a lower end rim of the guide partition wall.