BACKGROUND OF THE INVENTION
1. Field of the Invention
An electrical connector for insulated conductors includes a housing containing a chamber and having a conductor opening communicating with the chamber, a bus bar mounted in the chamber adjacent the conductor opening, a compression spring mounted in the chamber for biasing the bare end of an insulated conductor inserted into the chamber via the conductor opening into electrical engagement with the bus bar, a retaining device normally retaining the spring in a retracted inoperable condition, and a manually operable release member for releasing the spring to its operable condition.
2. Description of Related Art
As shown by the prior patents to Beege et al U.S. Pat. No. 6,280,233 and Fricket et al U.S. Pat. No. 6,796,855, among others, it is known in the prior art to provide access openings in a connector housing to permit the entry of the tip of a tool into the housing central chamber to release the leg of a clamping spring that biases a bare conductor into electrical engagement with a conductor. It is also known to provide a connector having sectional operating members including a pair of rigid sections joined by an intermediate flexible section, as shown by the patent to Ziemke et al U.S. Pat. No. 7,063,557.
The most varied embodiments of such connection devices are known, especially as designed according to the direct plug-in technique (also called “push-in” connections), for example, according to the German patent No. DE 30 19 149 C2. This reference shows a screwless connection terminal with a compression spring that is used in order to firmly clamp a conductor in a clamping point between a free leg of the compression spring and a bus bar.
To be able to introduce the conductor into the clamping point, there is provided a catch arm on which one can lock the clamping leg of the compression spring in a position in which the clamping point is opened so that one can introduce a conductor. To release the compression spring from the catch position, one uses a release bridge on the catch arm that is actuated by the free conductor end itself, which end is pushed into the clamping point. This solution entails a disadvantage to the effect that the release bridge cannot be separated when a very fine-wire conductor is introduced.
The present invention was developed to avoid the above and other drawbacks of the known connector devices, especially when used with delicate fine-wire conductors.
SUMMARY OF THE INVENTION
A primary object of the present invention is to provide an electrical connector including a housing containing a chamber in which is mounted a bus bar, spring means for biasing into electrical engagement with the bus bar the bare end of an insulated conductor that is inserted into the chamber via a conductor opening, retaining means for retaining the spring means in a retracted inoperable condition to permit the insertion and removal of the conductor bare end relative to the chamber, and manually operable release means for releasing the spring means for operation to its expanded operable condition.
In one embodiment, the release member is connected for sliding movement between releasing and retaining positions, and the housing contains a reset access opening. In a second embodiment, the release member includes a pair of rigid sections joined by a flexible section, the release member being movable between retaining and releasing positions by operating buttons at exposed ends of the sections.
According to another object of the invention, means are provided for resetting the connector apparatus to its initial open condition. In the first embodiment the reset means includes spring means for automatically biasing the release member toward its original retaining position relative to the housing. In the second embodiment, the sectional U-shaped release member is manually operable between its releasing and retaining positions by the alternate operation of push buttons that are arranged at opposite ends of the U-shaped release member and extend from a common surface of the connector housing.
According to the present invention, a housing formed from electrical insulating synthetic plastic material is provided for the tool-free wiring of a conductor with a bus bar and a clamping spring for the purpose of clamping the conductor firmly on the bus bar, which has at least one base leg and one clamping leg. It furthermore uses a combined catch-and-release element, which is movable with relation to the clamping leg and to the bus bar and which has a device, preferably an undercut, for the purpose of locking the catch-and-release element and/or the clamping leg in its opening position and which includes an actuation lug that can be actuated manually without any tools for the purpose of releasing the catch position and for movement into a conductor clamping position in which it releases the clamping leg.
The connection device can be wired extremely easily and quickly by hand and can easily be unwired, for example, with a tool such as a screwdriver. It is furthermore suitable also for particularly fine-wire conductors by virtue of the manually operable catch-and-release element. The locking action results in a defined, precisely detectable opening position.
The connector has a simple and compact structure and is suitable for the most varied uses, for example, as a connection device for terminal blocks and other kinds of electrical appliances. It is particularly suitable for power safety switches or terminal blocks. It can also be used in the PCB field (printed circuit field) or in heavy plug-in connectors.
Actuation depressors are of course known, especially also on screwless direct plug-in clamps. But they are used for pressing down the clamping leg (see, for example, German patent No. DE 41 202 784 C2) and they do not have any perceptibly locked-open position.
Preferably, the actuation button or lug is so fashioned that it will be manually operable without any tools. Less preferred are embodiments that are to be actuated with a tool such as a screwdriver or a pin.
The connector of the present invention is particularly advantageously supplemented and further developed in the following manner: The base leg is so designed that when the connection device is unwired, the catch-and-release element is automatically reset by the force of the spring into its unwired position.
Preferably, the clamping spring is a spring that works like a compression spring on the conductor in the wired state because such arrangements offer a particularly compact and low-cost structure.
According to another advantage of the invention, but as a variant or version that can also be independently considered as an invention, the clamping leg can be moved with the catch-and-release element, especially in a tool-free manner, both into an engaged and open position as into a wired and disengaged position and can be locked there in each case. In that way, both the wiring and unwiring can be done without any tools and, in particular, fine-wire conductors can be handled with a push-in technique by way of manual actuation. Here again, it is possible to preset the open position in a pre-assembled fashion “at the factory,” something which facilitates handling at the place of actual employment.
This can be done in a particularly simple manner in terms of design according to a particularly preferred version as follows. The catch-and-release element has two actuation lugs or buttons that protrude upward out of the insulation material housing, which lugs are arranged parallel to each other in shaft-like recesses of the insulation material and which are connected with each other via a band-like flexible segment, whereby the catch-and-release element preferably can be locked in the insulation material housing in the wired and in the unwired position and, in the process, engages or releases the clamping leg.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent from a study of the following specification, when viewed in the light of the accompanying drawing, in which:
FIG. 1 is a sectional view of a first embodiment of the connector of the present invention with the release member in its retaining position and the spring means retained in it retracted inoperable condition;
FIG. 2 illustrates the apparatus of FIG. 1 with the bare end of a conductor inserted into the connector housing chamber;
FIG. 3 is a perspective view of the apparatus of FIG. 2;
FIG. 4 is a sectional view illustrating the connector of FIG. 2 with the release member in its releasing position and the spring in its expanded operable condition;
FIG. 5 is a sectional view of a second embodiment of the invention with the sectional release member in its releasing position and with the spring in its expanded condition;
FIG. 6 is a sectional view of the apparatus of FIG. 5 with the sectional release element in its retaining position and the spring in its retracted inoperable position;
FIG. 7 illustrates the arrangement of the bare end of the insulated conductor prior to insertion into the connector housing chamber of the apparatus of FIG. 6; and
FIG. 8 is a sectional view illustrating the apparatus of FIG. 7, when the sectional release member is in it releasing position and the spring is in its expanded operable condition.
DETAILED DESCRIPTION OF THE INVENTION
Referring first more particularly to FIG. 1, the electrical connector of the present invention includes a connector housing 1 that is formed of an electrically insulating synthetic plastic material and contains a central chamber 1a within which is mounted a bus bar 3. The connector housing 1 contains a conductor opening 13 and a release opening 17 that communicate with the central chamber 1a. The bus bar 3 has a first linear portion 3a that extends parallel with the axis of the conductor opening 13, and an orthogonally extending portion 3b that is adapted for connection with an electrical circuit (not shown). Also mounted within the housing chamber 1a is a resilient clamping spring 4 having a fixed base portion 4a, a first leg portion 4b that is connected with one end of the base portion 4a by a curved connecting portion 4c, and a second leg portion 4d that extends orthogonally from the other end of the base portion 4a. The base portion 4a is supported within the housing chamber 1a by conventional cage means 21. Mounted for sliding movement in the housing 1 is a release element 5 that includes a main body portion 5a that is guided for sliding movement in the housing in a direction parallel with the first bus bar portion 3a. The release element 5 includes a transverse ledge portion 5b that is connected with the body portion 5a by a support plate 5c. As shown in FIG. 1, the ledge portion 5b is provided with a notch or recess 14 that is engaged by the free extremity of the first leg portion 4b of the clamping spring 4, whereby the ledge portion 5b and the notch 14 retain the first clamping leg 4b in a retracted inoperable position against the inherent biasing force of the resilient clamping spring.
Referring to FIG. 1, bare end portion 11 of an insulated conductor 12 is adapted for insertion into the chamber 1a via the conductor opening 13. As shown in FIG. 2, the bare end 11 of the conductor 12 extends through an opening 16 contained in the ledge portion 5b of the release member 5, with the end extremity of the bare conductor 11 being seated upon the transverse portion 3b of the bus bar 3. In FIG. 2, the first leg 4b of the clamping spring 4 is retained in the retracted position by the ledge portion 5b and the retaining notch 14. As shown in FIGS. 1-3, the clamping spring second leg portion 4d extends beneath the ledge portion 5b of the release member 5. The release member 5 extends upwardly beyond the upper surface of the connector housing 1 and terminates in an operating button 15. When the operating button 15 is manually depressed as shown in FIG. 4, the ledge portion 5b is displaced downwardly relative to the clamping spring 4, whereupon the extremity of the first spring leg 4b is released from the notch 14, and expands outwardly from the base portion 4a, whereupon the extremity of the leg portion 4a engages the air conductor 11 and biases the same laterally into electrical engagement with the linear first bus bar portion 3a. During this downward displacement of the release member 5 by the application of pressure to the operating button 15, the second spring leg 4d is displaced downwardly by the ledge portion 5b, as shown in FIG. 4. The conductor 11, which could, for example, be a delicate fine-wire conductor, is maintained in firm contact with the first bus bar portion 3a by the resilient biasing force of the spring leg portion 4b, which leg portion is biased outwardly toward its fully expanded position relative to the spring base portion 4a.
To release the conductor 12 of FIG. 4 from the connector housing 1, a releasing tool, such as the tip of a screwdriver, is inserted into the chamber 1a via the access opening 17, whereupon the tip of the tool causes the first leg 5b to be compressed toward its retracted position relative to the spring base portion 4a. The bare end 11 of the conductor 12 is then released to permit removal of the conductor from the connector housing, and owing to the biasing force of the second spring leg 4d reacting with the ledge portion 5b, the release member 5 is displaced upwardly and reset to the retaining position of FIG. 1, whereupon the resilient leg 4b of the spring 4 is retained in its retracted compressed inoperable condition by the notch 14.
Referring now to FIGS. 5-8, according to a second embodiment of the invention, the connector housing 101 contains a central chamber 101a within which is mounted the bus bar 103 having a first portion 103a, and an orthogonally extending second portion 103b. Supported within the housing chamber 101a by cage means 121 is a compression spring 104. In this embodiment, the compression spring 104 is formed by stamping and bending a resilient metal plate to define a base portion 104a, and a first leg portion 104b that is connected to the base portion by a curved connecting portion 104c. In this embodiment, a sectional release member 105 is provided having a rigid first section 105a, a rigid second section 105b, and a flexible intermediate section 105c connected between corresponding ends of the first and second sections 105a and 105b. At least the first and second sections of the release member are formed from a rigid electrically-insulating synthetic plastic material. The rigid sections 105a and 105b are slidably mounted in the connector housing 101 on opposite sides of the first bus bar portion 103a, and the sections extend upwardly beyond the upper surface of the connector housing and carry operating buttons 115 and 116, respectively. The flexible intermediate section 105c, which contains a plurality of longitudinally spaced notches 125 for imparting the appropriate flexibility to the section, is guided for movement relative to a semi-circular guide tract 118 provided within the housing 101. The operating button portions 115 and 116 are guided in corresponding guide slots 123 and 124, respectively, contained in the connector housing 101. The rigid first section 105a of the release member 105 contains a projecting portion 119 that extends across the first leg portion 104b of the compression spring means 104.
In the apparatus illustrated in FIG. 5, the first leg portion 104b is in its fully extended position in engagement with the first bus bar portion 103a. The release member 105 is retained in this initial released condition by the cooperation between a projecting integral lug 120 on the section 105a and the support portion 101b of the connector housing. Upon the manual application of a downward force to the operating button 115, the rigid first section 105a is displaced downwardly relative to the connector housing, whereupon the projecting portion 119 on the release member compresses the clamping spring leg 104b toward the base portion 104a of the clamping spring 104, thereby to retain the clamping spring in an inoperable retracted condition. As shown in FIG. 7, the bare end of 111 of the insulated conductor 112 is then inserted within the chamber 101a via the conductor opening 113, whereupon the lower extremity of the bare conductor 111 engages the base portion 103b of the bus bar 103, as shown in FIG. 8. During the downward travel of the first section 105a of the release member, the projection 120 is displaced to a position below the transverse first portion 101b of the housing 101, thereby to retain the first spring leg portion 104b in its compressed retracted position. After the conductor is inserted into the chamber via the conductor opening 113, the operating button 116 is manually operated to depress the second rigid section 105b of the release member 105. This downward movement of the section 105b is transmitted to the first section 105a via the guided motion of the intermediate section 105c upon the fixed guide surface 118 of the housing 101, thereby to displace the first section 105a upwardly relative to the housing. The spring leg 104b is thus released and expands toward its expanded position, thereby engaging the bare conductor 11 and biasing the same laterally into electrical engagement with the bus bar portion 103a. Thus, the conductor 11 is maintained in electrical engagement with the bus bar portion 103a by the resilient clamping operation of the clamp leg 104b of the clamping spring 104.
To release the conductor from the connector housing, the operating button 115 is again displaced downwardly to retract the spring leg 104b toward its fully retained inoperable position illustrated in FIG. 5.
While in accordance with the provisions of the Patent Statutes the preferred forms and embodiments of the invention have been illustrated and described, it will be apparent to those skilled in the art that changes may be made without deviating from the invention described above.
Patent Application
20070099479
