Fastening Means for a Transformer Module and a Signal Generator for Mounting at a Signal Tower

The invention is directed to a fastening means for a transformer module and a signal generator for mounting at a signal tower. Fastenings for signal generators at a signal tower are known. German Utility Model G 89 02 750 discloses a combined mount that serves the purpose of fastening a signal generator to a signal tower for traffic light signal systems.

Since traffic light signal systems are being decentralized to an increasing degree and are operated with low-volt technology, it is required to undertake the voltage conversion in the region of the signal generator. In low-volt technology, a separate transformer having a corresponding fastening was arranged in the respective signal generator chamber for every chamber, as disclosed, for example, in German Utility Model G 87 15 847. A separate post block or terminal block having plugs was respectively required per light signal generator chamber for that purpose (German Utility Model 87 15 848). In such traffic signal systems, the cabling ensued star-like from the node control means to the respective signal towers or, respectively, signal generators.

German published application DE-OS 32 30 761 already discloses a traffic signal system wherein every signal generator is fed via a single two-lead line and is supplied with a separate control line for switching the individual signal lamps. The installation therein disclosed is designed to reduce and simplify the cables required, particularly at junctions and traffic control points with numerous traffic signal units. Each unit (1, 2) contains in a single housing the customary red (3) green (4) and amber (5) lamps, each of which is connected (11) through an individual switch (7) to the secondary side of a transformer (8) and also to a switching instrument (12). The transformer steps down the main voltage to a suitable voltage in the range 6 to 60 volts for the lamps. The switching instrument in each unit operates the lamp switches (7), receives switching signals and delivers lamp power circuit status signals to the central control unit (6) through a connecting signal lead (13). Preferably the second lead of a dual-lead connection between the switching and control instruments is provided by the zero lead (10) of the dual-lead power connection to the unit. The transformer primary winding is coupled by wires (9, 10) to the main supply (14) and the transformer reduces the voltage to a 12 volt supply. Operation of the selected lamp is effected by commands from the control activating the switch stage (12). This disclosed system is thereby operated in low-volt technology.

In modern traffic light signal systems, a transformer should be provided for the voltage conversion, together with rectifier and appertaining components for a plurality of signal generators or, respectively, signal generator combinations, potentially for all signal generator combinations of a signal generator tower.

It is therefore an object of the invention to create a fastening means for a signal generator that enables a power supply unit to be attached, enables a wiring or, respectively, connection chamber to be formed, and also guarantees a simple fastening or, respectively, mounting possibility at the signal tower.

This object is inventively achieved with a fastening means that comprises the following features:

a) A bottom trough or pan, having an applied multi-purpose holder and having a receptacle means for a transformer module as well as having a holding means and a cable opening for the signal generator, forms a post space or terminal space together with a cover in which a post block or terminal block is arranged;

b) The transformer module is secured with appertaining catch hooks thereon, being secured at corresponding catch noses in the receptacle means;

c) The transformer module comprises a transformer, rectifier and a lead;

d) The applied multi-purpose holder for mounting the fastening means to a signal tower comprises a cable channel region fashioned U-shaped, having a cable lead-through opening in the side wall of the bottom trough;

e) A cable wind-up means is provided in the terminal space;

f) The cover is held by at least one catch nose and one catch tongue which are applied to the bottom pan and engage into corresponding recesses of the cover.

In addition to allowing the connection of the actual signal generator that is usually composed of three signal generator chambers, the fastening means of the invention also allows the connection of a transformer module that undertakes the voltage conversion for a plurality of signal generators. Further, a post space or terminal space is created by this fastening means, the supply cable being preferably clamped in this terminal space and the signal generator cable that is likewise introduced thereunto is guided and may be potentially wound up in said terminal space.

The signal generator can be mounted at and secured to the signal tower, either at the head end or at a longitudinally proceeding tower such as a whip tower in the proven, traditional way with the multi-use holder applied with the fastening means.

In particular, the invention provides an advantageous embodiment of a fastening means for a transformer module and a signal generator, for mounting at a signal tower. For weatherproofing, the bottom pan (1) proceeds obliquely in the region of the cable lead-through opening (1d) and forms a sloping connecting floor (1k). The receptacle means (1b) is arranged under the sloping connecting floor (1k). A sealant (11) is arranged in the terminal space or post space in the region of the cable lead-through opening (1d). The cable wind-up means (1e) is advantageously formed by a pipe section that can be slotted and is applied to the bottom pan (1) over the cylindrical holding means (1n). A further sealant (8) is arranged in the post space in the region of the wind-up means (1e). Additionally, the transformer module (2) is sealed with a casting compound (2h). The cover (3) is held to the bottom pan (1) by a catch tongue (1q) which can be conveniently unlocked with a tool (12). A seal (3a) is applied between the cover and the bottom pan. These various sealing arrangements provide for weather resistance and provide a barrier against insect infiltration.

The advantages and the further development of the invention derive from the description of the invention with reference to an exemplary embodiment with appertaining drawings.

FIG. 1 is an elevational view of the fastening means with signal generator and transformer module at the signal tower;

FIG. 2 is a partial sectional view of the fastening means of FIG. 1;

FIG. 3 is a plan view of the fastening means of FIG. 1 with the cover removed for clarity;

FIG. 4 is a partial sectional view of the transformer module viewed generally along line IV--IV of FIG. 5; and

FIG. 5 is a sectional view of the transformer module, viewed generally along line V--V of FIG. 1.

FIG. 1 shows a fastening means F that is formed by a cover 3, a bottom pan 1 and the multi-use holder 1b. The bottom pan has perimeter sidewalls 1' and the cover has overlapping sidewalls 3' FIG. 1 shows the transformer module 2. The fastening means F is secured to a head end H of the signal tower 14 with the multi-use holder 1b, and with strap retainers 13. The fastening means F thereby has a fastening hook 1a hooked to the head end of the tower 14. The head end of the signal tower 14 is covered with a tower hood 9. A signal generator 10 has its upper end secured to the fastening means F of the invention. A lower end of the signal generator 10 is additionally fixed to the signal tower with the separate second multi-use holder in a known way with a strap retainer 13.

According to FIGS. 2 and 3, the fastening means F of the invention comprises a bottom pan 1 that has the applied multi-use holder 1b with the fastening hook la and a rated break point 1f at one end. The rated break point 1f serves the purpose of knocking the fastening hook 1a off (separating the fastening hook 1a from the holder 1b) when the fastening means is not to be secured to the head end of a signal tower but is to be secured proceeding longitudinally at the signal tower, for example at a whip tower. The multi-use holder 1b comprises a channel region 1c fashioned U-shaped through which the supply or, respectively, signal generator cable 4a, 4b or, respectively, cables 5a, 5b that come from the signal generator tower are guided. The bottom pan 1 is terminated with a cover 3 attached via catch mechanisms (described below) and forms a post space or terminal space or terminal chamber C with the cover 3 in which a post block or terminal block 7 is arranged. The cable ends 4c, 4d of the supply cable are connected thereto. The interlocking of the cover can ensue, for example, with a catch nose 1p mating with a corresponding recess 3b in the cover, and with a catch tongue 1q mating with a corresponding recess 3c in the cover 3, whereby the catch nose and catch tongue are applied to the bottom pan 1. The catch tongue 1q can expediently be disengaged with a tool 12.

The supply cable 4a, 4b that, for example, can comprise a power line having a cross-section of three times 1.5 mm.sup.2 and that can comprise an integrated coaxial cable having a cross-section of 0.5 mm.sup.2, is conducted through the cable lead-through opening 1d in the sidewalls 1' of the bottom pan 1. In this region, the bottom pan 1 comprises an obliquely proceeding pan floor that forms a slanting connecting floor 1k. The slanting floor is arranged such that the introduced cables 4a, 4b necessarily have their cable ends 4c, 4d rising in upward direction, so that no rain water can penetrate to the terminals. The cables 5a, 5b that come from the signal generator tower would also be similarly inclined, rising in an upward direction, in the region above the connecting floor 1k. The supply and signal generator cables 4a, 4b; 5a, 5b are expediently secured to the connecting floor 1k with cable clips 6. Rain water that may penetrate the cover 3 runs down the connecting floor 1k to the signal generator tower and can thereby drip off.

Under the sloping connecting floor 1k, the bottom pan 1 comprises a receptacle means 1l for the transformer module 2 that is secured very protected by this arrangement. A holding means 1n for the signal generator (signal generator not shown in FIG. 2) is also provided in the bottom pan 1, whereby the holding means 1n is generally cylindrically fashioned. A cable wind-up means or pipe section 1e is advantageously formed immediately thereabove, this means being expediently formed as a cylindrical piece with slotted sections 1e' for passing the cables into or out of the wind-up means 1e. An excess length of the signal generator cable 5e can be wound up around the wind-up means le so that only the necessary end is to be guided to the individual signal generator chambers.

A cover seal 3a, for example, is provided in and around an inner cover edge, such as the overlapping sidewalls 3', in order to protect the terminal space C against the penetration of rain and insects. A sealant 11 is applied in the region of the cable lead-through opening 1d, this sealant being formed by a block of expanded cellular material. A further sealant, for example a plug 8 of expanded cellular material is also arranged above or, respectively, in the pipe section 1e, this preventing the penetration of insects into the signal generator chambers.

The fastening means F of the invention is shown in a plan view in FIG. 3. It may also be seen herein that the floor pan 1 of the fastening means F comprises reinforcing ribs or gusset plates 1h, which can be triangularly-shaped, in the region of the multi-use holder 1b. Additional reinforcing ribs are also applied to the sidewalls of the bottom pan 1, these ribs being referenced 1i.

FIGS. 4 and 5 show the transformer module 2 in a section from two different sides. The transformer module 2 comprises a housing 2d that is referred to as a transformer "can". The transformer module 2 is latched with at least two catch hooks 2i to corresponding catch noses 1o of the bottom pan 1, being latched thereto in the receptacle means 1l. A lead 2b is conducted from the transformer module 2 into the terminal chamber C of the fastening means F. As an example, the transformer 2f is secured to the heat-conducting plate 2a with a cable coupler 2g. The head-conducting plate 2a itself is secured to a catch nose 2e of the transformer can 2d with an opening 2e' provided for that purpose. The rectifier or rectifiers 2c are expediently attached to the heat-conducting plate 2a with, for example, screws. For heat and climate resistance, the transformer module is protected against environmental influences with a casting compound 2h.

Existing signal generators can be retrofitted at the signal tower at any time with a fastening means of the invention.

Although various minor changes and modifications might be proposed by those skilled in the art, it will be understood that we wish to include within the claims of the patent warranted hereon all such changes and modifications as reasonably come within our contribution to the art.