Information
-
Patent Grant
-
6176747
-
Patent Number
6,176,747
-
Date Filed
Thursday, December 3, 199826 years ago
-
Date Issued
Tuesday, January 23, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Sircus; Brian
- Prasad; Chandrika
Agents
-
CPC
-
US Classifications
Field of Search
US
- 439 721
- 439 722
- 439 723
- 439 724
- 439 711
- 439 712
- 439 715
- 439 718
- 439 755
- 439 709
- 439 7331
-
International Classifications
-
Abstract
A terminal block has a molded electrically insulative housing with through compartments containing terminal members each having a rectangular planar front section with a tapped hole for a terminal screw and three male terminal blades extending rearward from edges of the rectangular planar front section. The rectangular front section seats on ledges formed by bands integrally molded on opposing side walls of the compartments. Barbs projecting laterally from two facing male terminal blades engage the molded bands to secure the terminal member in the compartment. Partitions extending transversely between the front openings of the compartments provide electrical isolation between the screw terminals, and extend laterally beyond the molded body of the housing at both ends of the partitions to form mounting shoulders, which together with shoulders on projections molded on the housing body, secure the terminal block in an opening in a mounting panel. A cover integrally connected by a living hinge to a wall extending along one end of the partitions controls access to the screw connections on the planar front section of the terminal members.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to terminals blocks, and more particularly, terminal blocks with multiple male terminal blades for engagement by multiple female fast-on terminal connectors.
2. Background Information
A common type of terminal connector for connecting electrical wiring is the fast-on connector in which a female connector slides on and clamps a male terminal blade. In one arrangement, a male terminal blade is formed integrally with a screw connection provided by a transverse tab with a threaded aperture. A molded terminal block has a plurality of side-by-side recesses in each of which the tab of a terminal is seated with the male terminal blade projecting through a slot extending toward the rear. The male terminal blade extends through and beyond a tubular extension molded on the rear of the terminal block. The male terminal blade is centrally aligned with a tab by an offset which has barbs for securing the terminal in the molded block. A flange on the tab opposite the offset also has retaining barbs.
The female fast-on connector is provided on the lead to be terminated. Selective connection to this lead can then be made by securing another lead to the screw connection. In some applications, there is a need to terminate more than one lead with a common termination. One such application is the termination for secondary wiring in switchgear assemblies for electric power distribution systems.
There is a need, therefore, for an improved terminal block which accommodates the termination of multiple leads with a common terminal point. There is a more particular need for such an improved terminal block which provides for multiple terminations using fast-on connectors for the terminated leads.
SUMMARY OF THE INVENTION
These needs and others are satisfied by the invention which is directed to a terminal block which comprises a molded electrically insulative housing having at least one, and typically a plurality, of compartments having a front opening and a rear opening, electrically conductive terminal members are provided in the compartments. These terminal members comprise a planar front section and at least a pair, and preferably three, integral male terminal blades extending rearward from edges of the planar front section. The planar front section has a threaded aperture which receives a terminal screw. The terminal member is secured in the compartment with the planar front section extending transversely across the compartment and accessible from the front opening and with the male terminal blades extending toward, and accessible from, the rear opening.
Preferably, the compartments in the molded housing are rectangular in cross-section and extend through the housing from the front opening to the rear opening. The planar front sections are rectangular and sized to extend across the compartment with the male terminal blades extending from edges of the planar front section.
In the preferred terminal block where the terminal member has three male terminal blades, two facing male terminal blades extend from first and second parallel edges of the rectangular front section and a middle male terminal blade extends from a third edge between the first and second edges. The facing blades have integrally formed laterally extending barbs which engage the housing to retain the terminal member in the compartment. In the preferred form of the invention, opposing side walls of the compartments have ledges recessed from the front opening. The first and second parallel edges of the planar front section of the terminal member are wider than the facing male terminal blades thereby forming shoulders which seat on the ledges. Preferably, the ledges are formed by molded bands extending across opposing side walls within the compartments. One band has an axially extending slot through which the middle blade extends. Most preferably, the middle blade of the terminal member extends from a recess in the third edge of the planar front section and the axially extending slot in the one band has a depth less than the width of the ledge so that the middle leg is inwardly spaced from the walls of the compartment for easier engagement by a female fast-on connector. In another embodiment of the invention, the terminal member has another middle blade extending from a fourth edge of the planar front section substantially parallel to the first middle blade.
In one embodiment of the invention, the housing has a molded body in which the compartments are formed and includes partitions which extend transversely between the compartments adjacent the front openings. The terminal block can be adapted for mounting in a mounting opening in a mounting panel by extending the partitions laterally beyond the molded body to form aligned first mounting shoulders at both ends of the partitions. Projections molded on the body form second mounting shoulders spaced from the first mounting shoulders to form mounting slots in which the mounting panel is received to mount the terminal block in the mounting opening.
As another aspect of the invention, the terminal block can have a hinged cover over the screw connections. In this arrangement, an end wall is provided at one end of the partitions and the cover is connected to this end wall by an integrally molded living hinge. In the preferred arrangement, the cover can have apertures through which the screws are accessible even with the cover closed. In the preferred form of the terminal block, the male terminal blades are fully contained within the compartment in the housing but accessible through the rear opening.
BRIEF DESCRIPTION OF THE DRAWINGS
A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which:
FIG. 1
is an isometric view of a terminal block in accordance with the invention shown with the cover open and one of the terminal members removed.
FIG. 2
is a rear isometric view of the terminal block of
FIG. 1
with the cover closed.
FIG. 3
is an exploded isometric view of a three-bladed terminal which forms part of the terminal block of
FIGS. 1 and 2
shown together with a terminal screw and clamp.
FIG. 4
is a longitudinal sectional view through a portion of the terminal block.
FIG. 5
is a cross-sectional view taken along the line
5
—
5
in FIG.
1
.
FIG. 6
is a rear elevation view of the terminal block with cover open.
FIG. 7
is an isometric view of a four-bladed terminal in accordance with another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to
FIGS. 1 and 2
, the terminal block
1
of the invention includes a housing
3
molded from an electrically insulative resin. The housing has a plurality of compartments
5
which are rectangular in cross-section and extend through the housing
3
from a front opening
7
to a rear opening
9
. Referring also to
FIGS. 4 and 5
, a pair of integrally molded bands
11
and
13
on opposing sidewalls
15
and
17
of the compartments
5
form ledges
19
and
21
. A slot
23
extends longitudinally through the band
11
. This slot
23
has a depth which is less than the width of the ledge
19
. A raised area
24
extends forward on the side wall
15
beyond the ledge
19
and is co-extensive with the bottom of the groove
23
, as best seen in FIG.
1
. Narrow ledges
25
are integrally molded in the other sidewalls
27
in the compartment
5
at the same level as the rearward edge of the bands
11
and
13
.
Mounted in each of the compartments
5
of the terminal block
1
is a terminal member
29
. As best seen in
FIG. 3
, each terminal member
29
which is fabricated from electrically conductive sheet material has a planar front section
31
with a centrally located tapped aperture
33
. This planar front section
31
is rectangular and sized to pass through the front opening
7
in the compartment
5
. A screw
35
with a captured clamp plate
37
engages the tapped aperture
33
to form with the terminal member
29
a screw termination
38
.
Integrally formed with the planar front section
31
of the terminal member
29
are facing male terminal blades
39
and
41
which extend perpendicular to the planar front section
31
from first and second parallel edges
43
and
45
on the planar front section
31
. These facing blades
39
and
41
do not extend the full width of the edges
43
and
45
thereby leaving shoulders
47
and
49
. In addition, each of the blades
39
and
41
have barbs
51
and
53
formed adjacent the shoulders
47
and
49
. A middle blade
55
extends downward from a third, intermediate edge
57
of the planar front section between the first and second edges
43
and
45
. This middle blade
55
extends perpendicular to the planar front section
31
from a recess
59
in the intermediate edge
57
. As can be seen, the flat middle blade
55
is perpendicular to the flat facing blades
39
and
41
.
The terminal member
29
is inserted into a compartment
5
in the housing
3
until the shoulders
47
and
49
seat on the ledges
19
and
21
(as best seen in FIG.
4
). The middle blade
55
extends through the slot
23
in the molded band
11
. As the depth of the slot
23
is less than the width of the ledge
19
, the middle blade
55
is spaced from the walls of the compartment adjacent the rear opening
9
as shown in FIG.
5
. Similarly, the ledges
25
space the facing blades
39
and
41
from the walls of the compartment
5
. This is important because the blades
39
,
41
and
55
form the male elements of fast-on connectors which include a female connector (not shown) which slides onto and engages the male element.
With the terminal member
29
seated against the ledges
19
and
21
, the barbs
51
and
53
dig into the molded bands
11
and
13
to retain the terminal member seated against the ledges
19
and
21
as best seen in FIG.
4
.
The molded housing
3
also includes integral partitions
61
extending transversely between the compartments
5
. These molded partitions extend laterally beyond the molded body
62
of the housing at each end to form first mounting shoulders
63
. Also integrally formed with the molded housing are projections
65
which form second mounting shoulders
67
spaced from the mounting shoulders
63
formed by the partitions. The first and second mounting shoulders
63
and
67
form mounting grooves
69
which are engaged by the edges of a mounting opening
71
in a mounting plate
73
.
Preferably, the terminal block
1
is provided with an integral cover
75
.
This cover is connected to the housing
3
by a living hinge
77
integrally formed with an end wall
79
extending along one end of the partitions
61
. A pair of notches
81
in a lip
83
extending along the free end of the cover
75
engage latch tabs
85
on aligned partitions to secure the cover in the closed position. As a longitudinal wall extension
79
is only provided along one end of the partitions
61
, openings
87
are provided for electrical leads (not shown) connected to the terminal screws
35
even with the cover
75
in the closed position as seen in FIG.
2
. Openings
89
in the cover
75
aligned with the terminal screws
35
, allow insertion of test probes with the cover closed.
With the terminal block
1
of the invention, up to three leads can be terminated to a common point through fast-on female connectors (not shown) engaging the male blade elements
39
,
41
and
55
. A connection to this common termination point can be made through the terminal screw
35
. With the terminal block
1
mounted in a mounting opening
71
in the mounting plate
73
, the leads to be commonly terminated are separated from the termination lead.
In some applications, there may be a need for a terminal member with an additional male fast-on termination making a total of four such connections. Such a terminal member
29
′ is shown in FIG.
7
. The fourth blade is an additional middle blade
85
extending downward from a recess
87
in a fourth, middle edge
89
of the planar front section
31
between the end edges
43
and
45
. This fourth blade
85
is spaced from and substantially parallel to the other middle blade
55
.
While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of invention which is to be given the full breadth of the claims appended and any and all equivalents thereof.
Claims
- 1. A terminal block comprising:a molded electrically insulative housing having at least one compartment with a front opening and a rear opening; and at least one electrically conductive terminal member comprising a planar front section and at least two integral blades extending rearward from edges of said planar front section forming male terminals, said planar front section having a threaded aperture, and a terminal screw engaging the threaded aperture, said at least one terminal member being secured in said at least one compartment in said housing with said planar section facing and accessible through said front opening and said at least two blades extending toward and accessible through said rear opening.
- 2. The terminal block of claim 1 wherein said housing has a plurality of side-by-side compartments and an electrically conductive terminal member in each of said plurality of compartments.
- 3. The terminal block of claim 2 wherein said compartments are rectangular in cross-section and extend through said housing from said front opening to said rear opening, said planar front sections of said terminal members are rectangular and sized to extend across said compartment with said blades extending toward said rear opening from edges of said planar front section.
- 4. The terminal block of claim 3 wherein said electrically conductive terminal members have three blades including two facing blades extending from first and second parallel edges of said rectangular planar front section, and a middle blade extending from a third, intermediate edge of said planar front section between said first and second edges.
- 5. The terminal block of claim 4 wherein two opposing side walls of said compartments have ledges recessed from said front opening and said first and second edges of said planar front section are wider than said facing blades to form shoulders which seat on said ledges.
- 6. The terminal block of claim 5 wherein said ledges in said compartments are formed by molded bands extending across said opposing side walls, one of said molded bands having an axially extending slot through which said middle blade extends.
- 7. The terminal block of claim 6 wherein said middle blade extends from a recess in said third edge of said planar front section of said terminal member and said axially extending slot in said one molded band has a depth less than a width of the ledge of said one molded band.
- 8. The terminal block of claim 6 wherein said facing blades have laterally extending barbs which engage said bands to resist unseating of said planar front section from said ledges.
- 9. The terminal block of claim 4 wherein said three blades are fully contained within said compartments.
- 10. The terminal block of claim 4 wherein such electrically conductive terminal members have four blades including an additional middle blade extending from a fourth, intermediate edge of said planar front section between said first and second edges and generally parallel to said third blade.
- 11. The terminal block of claim 10 wherein said four blades are fully contained within said compartments.
- 12. The terminal block of claim 4 wherein said facing blades have laterally extending barbs which engage said housing to retain said terminal members in said compartments.
- 13. The terminal block of claim 2 wherein said compartments are formed in a molded body of said housing, and said molded housing has integral partitions projecting outward from the molded body between said compartments adjacent said front openings.
- 14. The terminal block of claim 13 adapted for mounting in a mounting opening in a mounting panel wherein said partitions extend laterally beyond said molded body to form aligned first mounting shoulders at both ends of said partitions, said housing further having projections on said molded body forming second mounting shoulders spaced from both of said first mounting shoulders to form mounting slots in which said mounting panel is received to mount said terminal block in said mounting opening.
- 15. The terminal block of claim 13 wherein said molded housing further has an end wall extending between one end of said partitions, and a cover integrally connected to said end wall by a living hinge and rotatable about said living hinge to cover and uncover said front openings of said compartments.
- 16. The terminal block of claim 15 wherein said cover has apertures aligned with said terminal screws.
US Referenced Citations (5)