Universal signal transmitter for a thermocouple connector head

A terminal block is disclosed having a pair of detachable tab portions enabling the terminal block to accommodate a mounting arrangement involving either a round-shaped housing unit resembling a DIN-style module or an oval-shaped housing unit resembling a U.S.-style module. In a first configuration of the terminal block, the detachable tab portions are removed to permit the terminal block to be mounted within a round-type terminal connector head. In a second configuration of the terminal block, the detachable tab portions remain connected to the terminal block to permit the terminal block to be mounted within an oval-type terminal connector head.

BACKGROUND OF THE INVENTION 
1. Field of the invention. 
The present invention generally relates to terminal blocks for use in 
terminal connector heads, and, more particularly, to an adaptive terminal 
block and body capable of being mounted within connector heads of various 
types. 
2. Description of the related art. 
Terminal connector heads are commonly used with temperature sensors to 
serve as a device for interconnecting the sensor leads to input terminals 
of a control processor. A temperature sensor typically includes a 
temperature sensing elements such as a thermocouple, which is encased in a 
protective tube. The sensing element supplies or varies an electrical 
signal to provide an indication of the temperature level within a 
monitored environment. The electrical signal needs to be transmitted to a 
process instrument for suitable translation into usable information 
available for analysis. Such a process instrument might be a digital 
processor in combination with an analog-to-digital converter. 
Terminal connector heads find particular use with temperature sensors 
because these sensing devices typically have short wires, preventing their 
direct connection to a remote facility. Terminal blocks provided in the 
form of an RTD-type transmitter are mounted within the terminal connector 
heads and interconnect the thermocouple to the process instrumentation. 
Standard connector heads includes a housing and a cover, in which the 
housing is provided with a process opening and an instrument opening. The 
protection tube or sheath of material surrounding a temperature sensing 
element is typically threaded at one end and threadably inserted into a 
nut adaptor formed at the process opening of the housing. The relevant 
wires of the sensing element are connected to the appropriate input 
terminals of the terminal block mounted within the housing. Connecting 
wires attached to the output terminals of the terminal block are routed 
through the instrument opening of the housing and suitably connected to 
the control and analysis equipment currently in use. During operation when 
the sensor is obtaining the relevant measurements, the interior 
compartment of the housing is sealed from adverse environmental conditions 
using the cover and by appropriately designing the terminal connector head 
and terminal block to withstand the expected conditions. For example, the 
terminal block may be formed of a high temperature ceramic while the 
connector head may be formed of a durable metal housing tailored to absorb 
significant impacts. 
Industry use of terminal connector heads features two distinct types of 
transmitter housing heads. The DIN style commonly found in European 
applications employs a mounting surface for the terminal block 
characterized by a substantially circular design on the order of 33 mm 
hole diameters. By comparison, the U.S. style used in domestic 
applications involves an oval-shaped housing providing a substantially 
elliptical mounting surface for the terminal block. The consequence of 
such disparate and incompatible mounting arrangements has meant that 
conventional systems are required to provide one terminal block having 
circular dimensions to fit within the DIN style housing head and another 
terminal block having oval dimensions to fit within the U.S. style housing 
head. This duplication of what is essentially the same component (except 
for the shape of the mounting surface) has heretofore been the prevailing 
condition within the relevant application fields, representing a 
diseconomy affecting the cost of the overall system and constituting an 
inefficient use of parts. 
SUMMARY OF THE INVENTION 
The present invention relates to a terminal block with a body having a pair 
of detachable tab portions enabling the terminal block to accommodate a 
mounting arrangement involving either a round-shaped housing unit 
resembling a DIN-style module or an oval-shaped housing unit resembling a 
U.S.-style module. In a first configuration of the terminal block, the 
detachable tab portions are removed to permit the terminal block to be 
mounted within a round-type terminal connector head. In a second 
configuration of the terminal block, the detachable tab portions remain 
connected to the terminal block to permit the terminal block to be mounted 
within an oval-type terminal connector head. 
As used in this application, the term terminal block is defined as an 
electronic component to connect together various electrical wires, 
including such components that connect together wires while operating as a 
signal conditioning device. Typical signal conditioning devices that are 
terminal blocks for this application include, but are not limited to, 
transmitter devices for use with RTDs, thermistors, thermocouples, and 
other measuring devices. Signal conditioning devices other than 
transmitters may also be utilized as terminal blocks. 
The invention comprises, in one form thereof, a terminal block for use in a 
terminal connector head, the terminal connector head being provided in one 
of a first head type and a second head type. The terminal block comprises 
a body and a pair of tab elements each integrally associated with the body 
and each defining a structure for use in mounting the terminal block to 
the terminal connector head. Each one of the pair of tab elements includes 
a first tab portion and an associated second tab portion, the second tab 
portion being detachably connected to the associated first tab portion. 
The first tab portion is used for mounting the terminal block to the 
terminal connector head when of the first head type and accompanied by the 
detachment of the second tab portion therefrom. The second tab portion is 
used for mounting the terminal block to the terminal connector head when 
of the second head type. The first head type of the terminal connector 
head includes, in one form thereof, a circular mounting surface in the 
respective terminal connector head; and the second head type of the 
terminal connector head includes, in one form thereof, an elliptical 
mounting surface in the respective terminal connector head. 
The first tab portion of each one of the pair of tab elements provides a 
slot, while the second tab portion of each one of the pair of tab elements 
includes a first ear section and an associated second ear section defining 
a slot therebetween which is registered with the slot provided by the 
first tab portion associated therewith. For each one of the pair of tab 
elements, the second tab portion is detachably connected to the associated 
first tab portion at a groove formed therebetween. 
The invention comprises, in another form thereof, a terminal block for use 
in a terminal connector head, the terminal block being operative in a 
first configuration thereof for attachment to a terminal connector head of 
a first type, the terminal block being operative in a second configuration 
thereof for attachment to a terminal connector head of a second type. The 
terminal block comprises a body and a pair of tab elements each integrally 
connected to the body and each including a first tab portion and an 
associated second tab portion, the second tab portion being detachably 
connected to the associated first tab portion. The terminal block in the 
first configuration thereof is secured to the terminal connector head of 
the first type using the first tab portion in accompaniment with the 
detachment of the second tab portion therefrom. The terminal block in the 
second configuration thereof is secured to the terminal connector head of 
the second type using the second tab portion. The first type of the 
terminal connector head includes, in one form thereof, a circular mounting 
surface in the terminal connector head; and the second type of the 
terminal connector head includes, in one form thereof, an elliptical 
mounting surface in the terminal connector head. 
The first tab portion of each one of the pair of tab elements provides, in 
one form thereof, a slot; and the second tab portion of each one of the 
pair of tab elements includes, in one form thereof, a first ear section 
and an associated second ear section defining a slot therebetween which is 
registered with the slot provided by the first tab portion associated 
therewith. Each of the first ear section and the second ear section 
associated with the second tab portion of each one of the pair of tab 
elements is detachably connected, in a preferred form thereof, to the 
first tab portion associated therewith at a respective groove which is 
sufficient to enable detachment of the respective ear section thereat. 
The invention comprises, in another form thereof, a terminal block for use 
in a terminal connector head, the terminal connector head being 
characterized by one of a first mounting arrangement and a second mounting 
arrangement with respect to the terminal block. The terminal block 
comprises a body and at least one tab element extending from the body. The 
at least one tab element includes a first tab portion permitting the 
attachment of the terminal block to the terminal connector head according 
to the first mounting arrangement, and further includes a second tab 
portion detachably connected to the first tab portion and permitting the 
attachment of the terminal block to the terminal connector head according 
to the second mounting arrangement. The first mounting arrangement, in one 
form thereof, is compatible with a circular mounting surface in the 
terminal connector head, while the second mounting arrangement, in one 
form thereof, is compatible with an elliptical mounting surface in the 
terminal connector head. 
The at least one tab element comprises, in one form thereof, a first tab 
element extending from the body at one side thereof; and a second tab 
element extending from the body at another side thereof. 
The first tab portion of each of the first tab element and the second tab 
element provides, in one form thereof, a slot, while the second tab 
portion of each of the first tab element and the second tab element 
includes an associated first ear section and second ear section defining a 
slot therebetween which is registered with the slot provided by the first 
tab portion associated therewith. 
The invention comprises, in yet another form thereof, a terminal block for 
use in a terminal connector head, the terminal block being operative in a 
first configuration thereof for attachment to a terminal connector head of 
a first type, the terminal block being operative in a second configuration 
thereof for attachment to a terminal connector head of a second type. The 
terminal block comprises a body and a means, integrally associated with 
the body, for defining a structure permitting the attachment of the 
terminal block in the second configuration thereof to the terminal 
connector head of the second type and being adaptive to permit the 
attachment of the terminal block in the first configuration thereof to the 
terminal connector head of the first type, wherein the first configuration 
of the terminal block is effected by the adaptive action. The terminal 
connector head of the first type includes, in one form thereof, a circular 
mounting surface; and the terminal connector head of the second type 
includes, in one form thereof, an elliptical mounting surface. 
The structure defining means comprises, in one form thereof, a pair of tab 
elements each integrally connected to the body and each including a first 
tab portion and an associated second tab portion, the second tab portion 
being detachably connected to the associated first tab portion. The first 
tab portion is used for attaching the terminal block to the terminal 
connector head when of the first type and in accompaniment with the 
detachment of the second tab portion therefrom. The second tab portion is 
used for attaching the terminal block to the terminal connector head when 
of the second type. 
The first tab portion of each one of the pair of tab elements provides, in 
one form thereof, a slot; and the second tab portion of each one of the 
pair of tab elements includes, in one form thereof, a first ear section 
and an associated second ear section defining a slot therebetween which is 
registered with the slot provided by the first tab portion associated 
therewith. The slot provided by the first tab portion of each one of the 
pair of tab elements is preferably sufficient to accommodate a screw 
extending therethrough for securing the terminal block to the terminal 
connector head at the respective first tab portion. The slot defined 
between the first ear section and the second ear section associated with 
the second tab portion of each one of the pair of tab elements is 
preferably sufficient to accommodate a screw extending therethrough for 
securing the terminal block to the terminal connector head at the 
respective second tab portion. 
The invention comprises, in yet another form thereof, a terminal block for 
use in a terminal connector head, the terminal block being operative in a 
first configuration thereof for attachment to a terminal connector head of 
a first type, the terminal block being operative in a second configuration 
thereof for attachment to a terminal connector head of a second type. The 
terminal block comprises a body including a pair of mounting elements, and 
a pair of tab elements detachably connected to the body. The terminal 
block in the first configuration thereof is secured to the terminal 
connector head of the first type using the pair of mounting elements of 
the body in accompaniment with the detachment of the pair of tab elements. 
The terminal block in the second configuration thereof is secured to the 
terminal connector head of the second type using the pair of tab elements. 
Each one of the pair of tab elements, in one form thereof, is detachably 
connected at least in part to a respective one of the pair of mounting 
elements. Each one of the pair of tab elements, in another form thereof, 
is detachably connected in full to a respective section of the body. The 
first type of the terminal connector head includes a circular mounting 
surface therein; and the second type of the terminal connector head 
includes an elliptical mounting surface therein. 
One advantage of the present invention is that the terminal block disclosed 
herein affords a dual-purpose use in which the same terminal block unit 
can be adaptively configured for mounting within either a round-type or 
oval-type terminal connector head by implementing the appropriate 
modifications (i.e., removal of the detachable tab portions for the 
round-type head). 
Another advantage of the present invention is that the terminal block 
affords a universal application with respect to the disparate DIN-style 
European head designs and U.S.-style head designs, eliminating the need to 
provide two separate housing-specific terminal blocks as required by 
conventional systems. 
Yet another advantage of the present invention is that the particular 
adaptation enabling the terminal block disclosed herein to realize its 
universal feature requires a simple structural change (i.e., removal of a 
detachable tab portion) that is easily implemented and does not diminish 
the overall design integrity.

DETAILED DESCRIPTION OF THE INVENTION 
Referring initially to FIGS. 5-7, there is shown a set of pictorial 
illustrations depicting a terminal block according to the present 
invention provided in a first and second configuration thereof. In 
particular, FIG. 5 is an upper plan view of the terminal block as provided 
in its original configuration with the detachable tab portions left 
intact, while FIG. 7 is an upper plan view of the terminal block as 
provided in its adapted configuration with the detachable tab portions 
having been removed. FIG. 6 is a lateral view taken in partial cut-away 
section of the terminal block of FIG. 5. The terminal block configuration 
illustrated by FIG. 5 permits the as-constructed terminal block to be 
mounted in the oval-type housing unit of FIG. 3, with the fully assembled 
unit being shown in FIG. 4. By comparison, the as-adapted terminal block 
configuration illustrated by FIG. 7 allows the modified terminal block to 
be mounted in the round-type housing unit of FIG. 1, with the fully 
assembled unit being shown in FIG. 2. 
Referring to FIGS. 5 and 6, there is shown respectively an upper plan view 
and a lateral partial cut-away view of terminal block 10 in accordance 
with one embodiment of the present invention. The illustrated terminal 
block 10 includes a body 12 and a pair of tab elements 14 and 16 
preferably disposed in integral connecting fashion to body 12 on opposite 
sides thereof. For purposes of brevity and not in limitation hereof, the 
discussion relating to tab element 14 applies equally to tab element 16 
since in a preferred form of terminal block 10 both of the tab elements 14 
and 16 share a common structure and function. 
Body 12 is generally provided in the form of a substantially cylindrical 
shell or casing structure closed at a lower end (visible in the FIG. 5 
view) and open at an upper end to enable an electrical component or other 
suitable device to be placed within the receptacle area generally 
indicated at 20 that is bounded by circumferential wall 18. The 
illustrated wall 18 takes the shape of an inwardly-facing rounded indent 
at a region thereof indicated generally at 22, but otherwise retains a 
substantially circular profile. Body 12 is provided with a passageway 24 
formed as a hollow tube-shaped upstanding pillar affording the ability to 
route wires from the back-side (i.e., the mounted side) of terminal block 
10 to the front side thereof for connection to the component or device 
being held therein. The term "electrical component" as used herein 
encompasses any device or structure having at least the ability to 
transmit signals received at an input terminal thereof to an output 
terminal thereof including, but not limited to, a terminal strip, passive 
circuitry, and active circuitry such as may involve signal processing or 
other forms of signal conditioning. 
The particular structure and dimensions of body 12 should not serve as a 
limitation herein as it should be apparent that any type, form, or 
arrangement of body 12 may be used in connection with the present 
invention. As will become more apparent below, the construction of body 12 
is generally guided by the objective of ensuring that the as-modified 
terminal block resulting from the removal of the detachable tab portions 
retains a mounting area compatible with a round-type terminal connector 
head. Body 12 is preferably formed of a durable thermoplastic or other 
suitable material depending upon the expected sensing conditions. 
The illustrated tab element 14 includes a first tab portion 26 and an 
associated second tab portion 28 detachably connected to first tab portion 
26 and comprising a first ear section 30 and an associated second ear 
section 32. Both tab portions 26, 28 are preferably planar formations 
ordered in their structure and orientation to establish a suitable 
mounting structure and/or arrangement for use in securably mounting 
terminal block 10. The first tab portion 26 is illustratively provided in 
the form of a horseshoe-shaped planar structure integrally formed to body 
12 at its lower end and having an upper surface sufficient to permit the 
head of a mounting screw extending through slot 34 to rest in secure 
abutting contact therewith. First tab portion 26 is generally 
representative of any arrangement providing a mounting structure for use 
in securing terminal block 10 into a substantially circular receiving 
area. The indent region 22 of wall 18 has first tab portion 26 extending 
therefrom at an outer surface thereof. By designing first tab portion 26 
so that it is compatible with round-type heads (i.e., it does not extend 
beyond the circular perimeter of body 12 in a manner preventing 
registration of terminal block 10 with round-type heads), the as-adapted 
terminal block 10 will be able to retain a generally circular mounting 
surface at the lower end of body 12 when second tab portion 28 is removed. 
This circular mounting surface is then suitable to serve as the mounting 
platform with respect to the round-type terminal connector head. In 
particular, after detachment of second tab portion 28, the mounting end of 
the modified terminal block 10 is compatible at least with the round-type 
European DIN terminal connector head. 
The illustrated second tab portion 28 includes first ear section 30 and its 
associated second ear section 32. Each ear section 30, 32 is detachably 
connected to first tab portion 26 (in part) and to body 12 (in part). 
However, it should be understood that the ear sections 30, 32 of second 
tab portion 28 may alternatively be provided in an arrangement in which 
the ear sections 30, 32 are detachably connected to only body 12, to only 
first tab portion 26, or to body 12 in part and to first tab portion 26 in 
part (as illustrated). This detaching connection is provided, in one form 
thereof, by a groove 36 formed between first ear section 30 and the 
relevant sections of body 12 and first tab portion 26, and by a groove 38 
formed between second ear section 32 and the relevant sections of body 12 
and first tab portion 26. Each groove 36, 38 is sufficient to enable the 
respective ear section 30, 32 to be removed by being completely broken 
away at the associated groove via a firm flexing or snap-off action. 
Alternative means may be provided other than grooves to establish the 
detaching connection. The illustrated ear sections 30, 32 define a slot 40 
formed therebetween that is sufficient to accommodate a mounting screw 
extending therethrough for securing terminal block 10 to the terminal 
connector head. This slot 40 is preferably registered with slot 34 
provided by first tab portion 26. 
The two pairs of illustrated ear sections 30, 32 of terminal block 10 are 
appropriately designed such that their integral association with body 12 
and first tab portion 26 defines, in combination therewith, a contour for 
the mounting end of the fully intact (i.e., as-constructed) terminal block 
10 that substantially corresponds to an elliptical shape compatible at 
least with the oval-type U.S. terminal connector head. Accordingly, the 
particular shape of the ear portions may encompass a wide variety of 
dimensional profiles provided that the resulting detachable tab 
arrangement effects an elliptical-type mounting surface contour in 
combination with body 12 and first tab portion 26. Although second tab 
portion 28 is provided as shown in the form of a pair of ear sections 30, 
32, the present invention is not so limited as this tab element may 
alternatively be provided as a single piece (and hence removed as a 
unitary whole) or as a multi-piece arrangement each separably removable. 
During operation, in the event that an oval-type housing module 50 is being 
used as shown in FIG. 3 with elliptical mounting area 51, the 
as-constructed terminal block 10 illustrated in FIG. 5 may be installed 
directly within the terminal connector head 52, as shown in FIG. 4 in the 
fully-assembled arrangement. In particular, mounting screws 54, 56 are 
provided through the respective slots 40 formed at the respective second 
tab portions 28 (i.e., between ear sections 30, 32 thereof) of terminal 
block 10 and threadably secured within respective threaded inserts 58 and 
60 provided within the mounting area 51 of terminal connector head 52, 
thereby securably mounting terminal block 10 to connector head 52. As a 
final measure to prepare for installation, the cover 62 is secured to head 
52 by a latch or other suitable locking mechanism to form a closed unit 
(not shown) fully encasing terminal block 10. The only entry points to the 
interior are provided by the conventionally known sensor access port 64 
and the processor access port shown at 66. 
During an alternative operation, in the event that a round-type housing 
module 70 is being used as shown in FIG. 1 with the circular mounting area 
71, terminal block 10 is re-configured as shown in FIG. 7 by removing the 
two pairs of ear sections 30, 32 associated with the respective ones of 
the second tab portions 28 to produce the modified form of terminal block 
10 having the indicated substantially circular contour. Mounting screws 
74, 76 are provided through the respective slots 34 formed at the 
respective first tab portions 26 of terminal block 10 and threadably 
secured within respective threaded inserts 78 and 80 provided within the 
mounting area 71 of terminal connector head 72, thereby securably mounting 
terminal block 10 to connector head 72. The utility of the respective 
indent regions 22 in body 12 is apparent, namely, they form an effective 
slot guide providing sufficient room for the round-head mounting screws to 
access the first tab portions 26. 
Although the terminal block disclosed herein provides a functional 
accommodation with respect to its selectable use within a mounting 
arrangement involving either a circular or elliptical mounting area, the 
present invention is not so limited to these particular geometrical 
configurations. Rather, the terminal block of the present invention 
encompasses the use of a tab element(s) to provide the capability to 
alternatively mount the terminal block within either a terminal connector 
head of a first type corresponding to a first geometrical mounting area 
(when the terminal block is in its as-constructed configuration) or a 
terminal connector head of a second type corresponding to a second 
geometrical mounting area (when the terminal block is in its as-modified 
configuration with the tab elements removed). The parameters of the second 
geometrical mounting area would subsist within those of the first 
geometrical mounting area. 
While this invention has been described as having a preferred design, the 
present invention can be further modified within the spirit and scope of 
this disclosure. This application is therefore intended to cover any 
variations, uses, or adaptations of the invention using its general 
principles. Further, this application is intended to cover such departures 
from the present disclosure as come within known or customary practice in 
the art to which this invention pertains and which fall within the limits 
of the appended claims.