1. Field of the Invention
An electrical connector for connecting to a bus bar the bare end of an insulated conductor, including a rectangular housing containing an open-topped chamber, a conductive L-shaped bus. bar arranged in the chamber with a vertical leg thereof extending adjacent one housing end wall, a generally planar clamping bar having a first end portion pivotally connected with the housing adjacent another end wall thereof for pivotal displacement about a horizontal pivot axis, and a spring arranged in the housing chamber for biasing the clamping bar upwardly in the housing, whereby when the conductor bare end is inserted downwardly into the housing, the free edge of the clamping bar clamps the conductor bare end into contiguous engagement with the bus bar vertical leg portion.
2. Description of Related Art
It is known in the patented prior art to provide electrical connectors including spring-biased clamping means for biasing a conductor toward locked engagement with a bus bar, as shown, for example, by the patents to. Beege et al U.S. Pat. No. 6,280,233, Fricke et al U.S. Pat. No. 6,796,855, Drewes et al U.S. Pat. No. 6,893,286, and Holterhoff et al U.S. Pat. No. 7,287,999, among others.
Various types of clamping means are used in connection with devices for connection or contacting of an electrical conductor. In a clamping position, a properly insulated or bare electrical conductor with a bus bar is moved into an electrically conducting connection via a clamping point of a clamping element by means of spring force. For this purpose, the conductor bare end that is to be connected is inserted into the connection device. The connection device can be opened by an actuation unit so that the conductor may be easily inserted and also extracted.
In the field of these connection devices and clamping units, there is a constant requirement for optimizing the structural space requirement coupled with low product costs mid a high degree of contacting safety.
The present invention was developed to create an improved clamping unit and an improved corrector arrangement.
Accordingly, a primary object of the present invention is to provide an electrical connector for connecting to a bus bar the bare end of an insulated conductor, including a rectangular housing containing an open-topped chamber, a conductive L-shaped bus bar arranged in the chamber with a vertical leg thereof extending adjacent one housing end wall, a generally planar clamping bar having a first end portion pivotally connected with the housing adjacent another end wall thereof for pivotal displacement about a horizontal pivot axis, and a spring arranged in the housing chamber for biasing the clamping bar upwardly in the housing. Thus, when the conductor bare end is inserted downwardly into the housing chamber, the free edge of the clamping bar clamps the conductor bare end into contiguous electrical engagement with the bus bar vertical leg portion.
According to another object of the invention, the spring biasing means comprises a leaf spring having a configuration that is Z-shaped, L-shaped, or U-shaped. The leaf spring includes a linear end portion that is pivotally connected with the housing end wall to which the clamping bar is pivotally connected. Alternatively, this leaf spring linear end portion may be secured in contiguous surface-to-surface contact with the bottom surface of the clamping bar. The length of the clamping bar is greater than the spacing distance between the end walls, whereby when the clamping bar is biased upwardly toward the released position, it is slightly downwardly inclined with the free extremity thereof in engagement with the bus bar vertical leg portion.
The clamping means of the connector combines the advantages of a so-called push-in clamping spring with a small structural width plus good contacting security, in that at least one supplementary spring element is arranged inside the defined interior space of the housing on the side of the clamping bar facing away from the conductor insertion side. In the prior art devices, on the other hand, the clamping bar itself is made elastic in a V-shaped manner. In contrast to this state of the art, the . present invention—as related to the particular conductor cross-section—provides a structural shape that is smaller, in particular, that is “shorter” in an x-direction normal to the conductor insertion direction (“z” in
In a preferred embodiment, the clamping bar is arranged in the housing chamber and includes a pivot segment that extends into a pivot opening contained in the housing end wall opposite the clamping point. This results in a simple structure. The housing can be formed by punching and bending from a metal sheet, whereby a recess can be punched to define the pivot axis in a simple manner. Besides, this facilitates simple assembly by merely inserting the clamping bar projection into the pivot opening.
The spring element can in each case be in contact with the clamping bar and with the cage, at least segment by segment. In other words, the spring element can have a surface that rests against the underside of the clamping bar. This resting position, however, can also be a contact line or a contact point. Besides, this resting position can be in the same or essentially the same position in each pivot position of the clamping bar, or it can change the position, that is to say, the segment of the spring element and of the clamping bars can move or shift with relation to each other. In another embodiment, the spring element can have a pivot segment by means of which it is pivotally attached in the front wall of the housing. For example, the same recess in the front wall can serve to receive the pivot segment of the clamping bar as well as the spring element.
In an alternate embodiment, the spring element can be made integral with the clamping bar, which facilitates a partial reduction. In one particular embodiment, the spring element can have a Z-shaped configuration with a straight spring pressure segment and a support segment that is essentially parallel thereto, which via a straight connection segment are connected in each case by an arc segment.
According to a further embodiment, the spring element can be L-shaped with a straight spring pressure segment and a connection segment that is essentially perpendicular thereto, which via two opposite arc segments is attached to the spring pressure segment.
In another embodiment, the spring element has a widened U-shaped configuration with a short spring pressure segment, which via an arc segment is attached on one end of a straight connection segment, which via another arc segment is connected with a straight support segment. This straight support segment can extend parallel to the foot segment of the bus bar and can rest on the foot segment of the bus bar. This results in a structure that can be useful for simple assembly. In another embodiment, the bus bar can be made without a foot segment, whereby, for example, a segment of the cage on the underside of at least one side wall serves as a thrust bearing for the straight support segment. It is furthermore possible that the housing might display only one side wall.
In yet another alternate embodiment, the spring element can have a widened U-shaped configuration with a short spring pressure segment, which via an arc segment is attached on one end of a bent connection segment, which via another arc segment is connected with a straight support segment. Here, the bent connection segment can have a rather essentially larger arc radius than that of the arc segments, whereby one arc segment can have a smaller arc radius than the other arc segment.
Furthermore, in another embodiment, the wider arc segment can rest upon the foot segment of the bus bar, whereby the straight support segment can extend along the front wall of the housing and can rest on the front wall. In this way, one makes use of the interior space and walls of the housing.
The various embodiments of the spring element can, if the housing and the clamping bar have the same shape, make it possible to use the clamping unit in a vast area. This facilitates an adaptation to differing clamping housing by means of the simple insertion of differing spring elements during assembly.
The connector includes a housing to receive a clamping unit, a bus bar and an insertion opening for the introduction of the electrical conductor into the clamping unit, preferably into the housing; a pivotable e clamping bar for the clamping and contacting of the electrical conductor on the bus bar, preferably arranged in the housing, and at least one spring element for the exercise of a force upon the clamping bar, whereby the clamping unit is made as a clamping unit as described above.
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:
Coordinate systems are illustrated in the figures, wherein x indicates the width direction, y indicates the depth direction, and z indicates the height direction.
Referring first more particularly to
The term “released condition” refers to the position (
Connector unit 1 comprises a housing or cage 2, an L-shaped bus bar 4, a linear clamping bar 5, and a leaf spring element 7. The bus bar could also be made integrally with the housing (it could be one of the walls of the housing), if that housing, for example, were to be formed from a well-conducting material (not shown here).
Housing 2 has two side walls 2a that lie parallel and opposite each other in x-z planes, which on one side (in
In an modification (not shown), housing 2 has only one side wall 2a, with a front end wall 2b and the retaining end wall 2c.
In its upper sector, front wall 2b is provided with a recess 2d, which in this case is rectangular and which extends through the front wall 2b in the x-direction and in the y-direction. The function of recess 2b will be explained further below.
With its side walls 2a, its front end wall 2b, the retaining wall 2c, and a bottom wall 2e, housing 2 contains an interior chamber 3.
Housing 2 can be a metallic punched and bent component, or an injection-molded part consisting of a synthetic plastic material. Other embodiments are naturally possible. It is also conceivable that a synthetic substance clamping support might act as a housing 2 if it has corresponding contours/walls.
Bus bar 4 is L-shaped and includes a vertical contact leg portion 4a adjacent the inner surface of end wall 2c, and a horizontal connector leg portion 4b arranged adjacent the housing bottom wall 2e. The horizontal leg portion has an end extremity 4f that extends outwardly from the housing chamber in the x direction for connection with an electrical conductor or the like.
In another embodiment, not shown, bus bar 4 does not have a foot segment 4b. In this case, on the lower point of at least one side wall 2a in place of the foot segment 4b of bus bar 4, there is attached a foot segment that is connected with the side wall, for example, it may be handed over or it may be molded on.
Arranged inside the upper portion of chamber 3 is a clamping bar 5 that is pivotally connected at one end with the housing for pivotal movement about a horizontal pivot axis 6. More particularly, the clamping bar includes an end projection 5b that extends into a pivot opening 2d contained in the upper end of the housing wall 2b. The length of the clamping bar 5 is greater than the spacing distance between the housing end walls 2b and 2c, whereby when the clamping bar is in the illustrated downwardly inclined released position, the clamping edge 5a at the free end of the clamping bar engages the inner surface 4e of the bus bar vertical leg 4a: Clamping bar 5 has an upper surface 5c that is downwardly inclined when the clamping bar is in the illustrated released position. The engagement of clamping edge 5a with the contact surface 4e of bus bar 4 constitutes a stop and limits the pivotal movement of the clamping bar in the counterclockwise direction.
Arranged in chamber 3 below the clamping bar 5 is a generally Z-shaped leaf spring 7 that biases the clamping bar upwardly toward the released position of
The linear spring pressure segment 7a extends below clamping bar 5 parallel to the latter over about ⅔ of its length and then runs into an adjoining arc segment 7b. Arc segment 7b has an opening angle between the spring pressure segment 7 and a connection segment 7g amounting to less than 90° in the clockwise direction and is connected with another arc segment 7c via a straight connection segment 7g. In this first exemplary embodiment, connection segment 7g is about ¾ the length of the spring pressure segment. The other arc segment 7c runs in opposition to the arc segment 7b with a similar opening angle between the connection segment 7g and a support segment 7d and transitions into a straight support segment 7b whose end rests on a support surface 4d of foot segment 4b of bus bar 4 near the transition of foot segment 4b into the contact segment. In the resting position, support segment 7d extends almost parallel to the spring pressure segment 7a.
With its upward-pointing surface acting as pressure segment 7f, the spring pressure segment 7a rests on the lower surface of bus bar 4, which is referred to as pressure segment 5d.
Spring element 7 is exposed to a certain prestress force by means of which clamping bar 5 with its clamping point is pressed in the opposite z-direction against the contact segment 4a in the clamping point.
Spring element 7 is arranged in the interior chamber 3 within a sector that is bordered by clamping bar 5, contact segment 4a, and the foot segment 4b of bus bar 4 as well as front wall 2b and the corresponding areas of side walls 2a of housing 2.
The introduced and clamped conductor 8 in the clamping point of clamping unit 1 is illustrated by
In the clamping condition, conductor 8 is biased toward the contact surface 4e of bus bar 4 and is clamped against the bus bar by the clamping edge 5a of clamping bar 5, owing to the spring force of spring element 7. Clamping bar 5 is pivoted around the pivot axis 6, just as the spring pressure segment 7a of spring element 7. Arc segment 7b of spring element 7 is widened in the clamping condition, that is to say, the opening angle between the spring pressure segment 7a and the connection segment 7g is greater than 90°. At the same time, the other arc segment 7c is further bent together, whereby the opening angle between connection segment 7g and support segment 7d is less than 90°. As a result, spring element 7 is under a greater pre-stress force than in the released position.
Clamping edge 5a of clamping bar 5 not only has the function of pressing conductor 8 against contact surface 4e, but also acts in the direction of extraction (opposite to the z-direction) of conductor 8 in such a manner that the extraction of conductor 8 out of clamping unit 1 is blocked, whereby the clamping effect is increased. This kind of self-inhibition is brought about by the swing axis 6 positioned on top and by the clamping edge 5a, which is in a lower position in that respect. The self-inhibition is enlarged by the pivot axis 6, which is in a higher position to the lower positioned clamping edge 5a due to the greater length of the front wall 2b of cage 2 in the z-direction opposite the unlatched side walls 2a. As a result, lever arms acting in the self-inhibition position in clamping bar 5 between the force introduction sector of the spring force of spring element 7 and the swing axis 6 as well as between the swing axis 6 and clamping edge 5a become as large as possible.
As shown in
The second exemplary embodiment differs from the first one by the structure of spring element 7′, which in this case in the resting position has a reverse L-shaped configuration and is arranged in the interior space 3 below clamping bar 5.
Spring element 7′ also has a spring pressure segment 7′a whose one end is shaped as pivot segment 7′e for insertion into the recess 2d of the front wall 2b, and, as in the first embodiment, is received below clamping bar pivot segment 5b in recess 2d. Spring segment 7′a forms the short leg of the L-shaped configuration of spring element 7′ and in the resting position with its pressure segment 7′f rests against pressure segment 5d of the underside of clamping bar 5 (
The other end of spring pressure segment 7′a transitions into arc segment 7′b, which has an opening angle of about 180° and which extends in the clockwise direction into the interior chamber 3. The other end of arc segment 7′b is connected with another arc segment 7′c that which runs counter to arc segment 7′b, which runs in an arched manner against the clockwise direction and which has an opening angle of about 45°. Its other end is connected with a straight connection segment 7′g essentially at a right angle and thus extends perpendicularly to the spring pressure segment 7′a (and thus also with respect to clamping bar 5 in that resting position) and which on its other end transitions into an arc-shaped support segment 7′d with an opening angle of about 90° bent against the clockwise direction. This arc-shaped support segment 7′d in the released position rests against the inside surface 2e of front wall 2b of housing 2. (For purpose of illustration, the end portion 7′d is shown in
In the released position of this second exemplary embodiment, clamping edge 5a also, as in the first exemplary embodiment, rests against clamping surface 4e of contact segment 4a of bus bar 4.
The insertion of the properly insulated end of conductor 8 takes place as described in the first exemplary embodiment. Spring element 7′ is stressed in that the support segment 7′d is supported against the inside surface 2e or recess 2d of housing 2. At the same time, arc segments 7′b and 7′c are widened and generate the spring force that acts upon the clamping bar 5 to clamp conductor 8 via clamping edge 5a against clamping surface 4e of contact segment 4a of bus bar 4.
The third exemplary embodiment also differs from the first and second by the structure of spring elements 7″. In the resting position, spring element 7″ has a widened U-shaped configuration and is also arranged in the interior space 3 below clamping bar 5. A spring pressure segment 7″a of spring element 7″ here is arranged very briefly on the end pointing toward front wall 2b of an arc segment 7″b with an opening angle of about 90°. Pressure segment 7″f is arranged on the side of spring pressure segment 7″a, which faces toward clamping bar 5 and of arc segment 7″b. Spring element 7″ does not have a pivot segment and does not extend in the recess 2d of front wall 2b. Only pivot segment 5b of clamping bar 5 is arranged in recess 2d in swing axis 6.
The other end of arc segment 7″b is a leg of the U-shaped configuration and is made as a straight connection segment 7″g. Connection segment 7″g runs at an angle of less than 90° with respect to clamping bar 5 toward left bottom or toward front wall 2b of cage 2 into the interior chamber 3 and transitions into another arc segment 7″c that runs at an arch bent against the clockwise direction and that has an opening angle between connection segment 7″g and the support segment 7″d amounting to less than 180°. Its other end is connected with a straight support segment 7″d that runs parallel to the foot segment 4b of bus bar 4 and that, with a lower support surface 7″i, rests on the support surface 4d of the foot segment 4b of bus bar 4. (For purpose of illustration, in
In the released position of this third exemplary embodiment, clamping edge 5a, as in the first and second exemplary embodiments, rest against clamping surface 4e of contact segment 4a of bus bar 4.
Fig, 14 and 15 show a fourth exemplary embodiment of the inventive clamping unit 1′″ in each case by way of a diagrammatic side view in the resting position and in the clamping position (
The fourth exemplary embodiment also differs from the first, second, and third by the structure of spring element 7′″. Spring element 7′″ in the released position also has a U-shaped configuration with a long straight leg and a shorter bent leg and also arranged in the interior space 3 below clamping bar 5. Spring pressure segment 7′″ a of spring element 7′″ here, similar to the third exemplary embodiment, is arranged on the front-wall-facing end 2b of an arc segment 7′″b with an opening angle of about 45°. The pressure segment 7′″f is arranged on the side of arc segment 7′″b, which faces toward clamping bar 5. This spring element 7′″ of the fourth exemplary embodiment also has a small spring segment and is not received in recess 2d of front wall 2b. Only swing segment 5b of clamping bar 5 is arranged in recess 2d in swing axis 6.
The other end of arc segment 7′″b is fashioned as an arc-shaped connection segment 7′″g with an essentially greater radius than that of arch segment 7′″b. Connection segment 7′″g runs toward left bottom to front wall 2b of cage 2 into interior space 3 and transitions into another arc segment 7′″c, which runs bent in the clockwise direction and which has an opening angle between the connection segment 7′″g and the support segment 7′″d amounting to less than 180°. Its other end is connected with the straight support segment 7′″d, which extends parallel to front wall 2b of cage 2 on the inside surface 2e of front wall 2b in the opposite z-direction, all the way over recess 2d, and which, with its support surface 7′″l, rests on the inside surface 2e of front wall 2b of cage 2. The length of this support amounts to about 9/10 of the length of front wall 2b.
In the released position of this fourth exemplary embodiment, clamping edge 5a, as in the case of the first, second, and third, exemplary embodiment, rests against the clamping surface 4e of contact segment 4a of bus bar 4.
The bent-together arc segment 7′″c generates the spring force, which in this fourth exemplary embodiment via the bent connection segment 7′″g of spring element 7′″ acts upon clamping bar 5 to clamp conductor 8 via clamping edge 5a against the clamping surface 4e of contact segment 4a of bus bar 4.
A conventional embodiment of the clamping point displays a reverse V-shaped spring element 7IV, whose one end is in a perpendicular position and is attached to the cage. The other end has a clamping point and presses against the contact surface 4e of contact segment 4a of the bus bar. Spring element 7′″ is arranged above interior space 3 and limits it toward the top. This requires a first horizontal dimension 9 from the attached leg of spring element 7IV toward contact segment 4a.
In the inventive clamping device, spring element 7 is arranged inside interior chamber 3, whereby the latter is used in a manner that was not the case earlier. Besides, in that way, one can achieve a second horizontal dimension 10, which is smaller than the first horizontal dimension 7 in the conventional embodiment. We thus get a smaller dimension 10 in the x-direction with the same connection possibilities (spring element in the excursion state).
Clamping units 1, 1′, 1″, 1′″. can also be inserted into a corresponding housing made of synthetic material and can constitute a connection device not illustrated. This connection device can also have an actuation unit (not shown) by means of which, for example, with a tool, clamping bar 5 can be swung in order to insert conductor 8 or to loosen the clamped conductor S and to pull it out.
The above-explained exemplary embodiments do not restrict the invention. It is modifiable in the context of the attached claims. The connection device can be made as a series terminal. In the first, second, and third exemplary embodiments, it is also conceivable to make clamping bar 5 and spring element 7 integrally.
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.
Number | Date | Country | Kind |
---|---|---|---|
20 2011 050 120.5 | May 2011 | DE | national |