Apparatus for measuring a workpiece

Apparatus for measuring a workpiece which includes a support structure for carrying a longitudinally displaceable guide carriage, which guide carriage in turn carries a measuring feeler. To accommodate precise measurement of relatively large objects, without the requirement of an excessively large and heavy single support structure for the longitudinally displaceable guide carriage, the support structure is formed of a plurality of identical support elements. Each of the support elements are provided at the respective opposite end plates with mounting pins and recesses interengagable in a force form-fitting manner so as to align and connect the support elements in a precise location relative to one another. The end plates of the support elements are provided with grooved bracket structure to accommodate passage of the carriage past the junction of two support elements.

BACKGROUND AND SUMMARY OF THE INVENTION 
The present invention relates to an apparatus for measuring a workpiece of 
the type consisting essentially of a supporting element and a 
longitudinally displaceable guide carriage carrying a measuring feeler. 
An exact measuring of a workpiece in more than one coordinate direction is 
conducted, as is known, most economically on a measuring plate by means of 
a gauge. However, in such a procedure, a measuring length can only be 
attained maximally which corresponds approximately to the length of the 
measuring plate. Objects of a very voluminous construction and objects 
which are fixedly mounted are in many cases measured by means of gauges, 
templates, castings, or the like. Since, as can be readily understood, 
considerable expenditures from the labor and money viewpoints are required 
for the manufacture of such devices, portable measuring devices have been 
created. 
A portable measuring apparatus as has been disclosed, for example, in DOS 
[German Unexamined Laid-Open Application] 1,548,352 consists substantially 
of a casing and a yardstick longitudinally displaceable therein. However, 
a disadvantage of this measuring device, which can be arranged at the 
object to be measured, is that only a relatively minor measuring length 
corresponding to the length of the yardstick can be obtained. 
Starting with this aspect, the present invention is based at least in part 
on the objective of providing a portable measuring device making it 
possible in a simple and economical manner to measure objects to be gauged 
which include those having great measuring lengths. 
The present invention contemplates providing at least one end zone of a 
supporting element with a mounting means by which the supporting element 
can be connected with at least one further identical supporting element in 
a force-derived and/or form-fitting coupling fashion. 
In a further development of the invention, the supporting element is 
equipped at both end zones with a mounting means. 
The advantage of this invention resides particularly in that a supporting 
element constructed in this way can be connected to a number of additional 
similar supporting elements so that a series of supporting elements of an 
arbitrary length and forming a single structural unit can be composed in a 
rapid and accurate manner, whereby a very great measuring length can be 
attained by means of a measuring device attached to this structural unit. 
These and further objects, features and advantages of the present invention 
will become more obvious from the following description when taken in 
connection with the accompanying drawings which show, for purposes of 
illustration only, a single embodiment in accordance with the present 
invention.

DETAILED DESCRIPTION OF THE DRAWINGS 
As shown in FIG. 2, respectively one supporting element 1 is equipped at 
both of its end zones at the end faces with a mounting or attachment 
means. The attachment means consists, on the one hand, of mating elements 
7 inserted in an end plate 5 of the supporting element 1 and, on the other 
hand, of recesses 8 provided in an opposed end plate 6 of the next 
adjacent supporting element 1. By means of the attachment means at least 
two supporting elements 1 can be detachably joined together, the end 
plates 5 and 6 facing each other and the mating elements 7 engaging the 
recesses 8. Advantageously, the supporting element 1 according to this 
invention furthermore affords the possibility of coupling an actually 
arbitrary number of supporting elements 1 together by a plug-in 
connection. The mutually facing end plates 5 and 6 of the supporting 
elements 1 are connected by screws, brackets, or the like, so that a rigid 
unit is produced, on which a measuring device 11 to measure a workpiece a 
can be disposed to be longitudinally displaceable. The supporting member 
1' illustrated as a total unit in FIG. 2 is subdivided, so to speak, into 
several supporting elements 1 detachably joined together by fastening 
means in a force-derived and/or form-fitting connection. 
A supporting element 1, illustrated individually with a generally 
rectangular box-like shape in FIG. 1, consists essentially of a base plate 
2 and a top plate 3 connected via two members 4. The supporting element 1 
may also have a square box-like shape. The supporting element 1 is 
preferably fashioned as a cast or welded construction. The mating elements 
7 inserted in the first end plate 5 are aligned with the recesses 8 
provided in the second end plate 6. The fitting dimensions of these 
recesses 8 are such that a fitting element having the same dimensions as 
the mating elements 7 can be introduced into any of the recesses 8 with 
the establishment of a sliding seat, i.e. in a force-derived connection. 
The mating elements 7 are preferably fashioned as mating pins, mating 
screws, mating springs, or the like. In the zone of the mating elements 7 
and the recesses 8, respectively two continuous bores 9 are provided which 
likewise are in alignment with each other (with corresponding bores 9 on 
the end plate of the next adjacent supporting element 1) and serve for the 
threaded connection by bolts or the like (not shown) of the mutually 
adjoining end plates 5 and 6. 
On the topside of the top plate 3, a guide rail 10 with a measuring scale 
is attached and extends substantially over the entire length of the 
supporting element 1. A guide carriage 12 carrying a measuring device 11 
has a recess 13 on its underside cooperating with the guide rail 10. The 
measuring device 11 consists essentially of a column 14 inserted in the 
guide carriage 12 and a receiving part 15 wherein a measuring rod 16 is 
disposed to be longitudinally displaceable. At the free end of the 
measuring rod, a receiving head 17 is mounted. A measuring feeler 18 or 
the like is inserted in the receiving head. 
The guide carriage 12 is equipped with two brackets 20 extending 
essentially over the entire width of the top plate 3 and extending 
underneath the latter by way of sections 21 at the marginal zone of the 
two longitudinal edges of the top plate. Thereby, the tilting of the 
measuring device 11 in case of shifts in the balanced position of the 
measuring sleeve 16 is prevented. In order to ensure, with a number of 
supporting elements 1 coupled together at the end faces, that in case of a 
longitudinal displacement of the guide carriage 12 the bracket sections 21 
can be passed through at the junction of end plates 5 and 6, respectively, 
the latter are provided each with recesses 22 in their upper zone. In 
place of the brackets 20, it is also contemplated to arrange other 
fastening means, such as screws or the like, for example, which are 
connected to the supporting element 1. 
To effect a rapid leveling of the supporting element 1, the latter is 
equipped with bubble levels 23 on its topside, which levels extend, on the 
one hand, in the longitudinal direction and, on the other hand, in the 
traverse direction of the supporting element 1. 
On the bottom plate 2 of the supporting element 1, a vertical adjustment 
device is provided consisting of setscrews 24. Casters 25 are arranged on 
the underside of the supporting element 1 to facilitate the transporting 
of a heavy supporting element. 
It is, or course, contemplated by other preferred embodiments of this 
invention to insert any other type of tool in the measuring device, for 
example, a scriber or the like. 
While I have shown and described several embodiments in accordance with the 
present invention, it is understood that the same is not limited thereto 
but is susceptible of numerous changes and modifications as known to those 
skilled in the art and I therefore do not wish to be limited to the 
details shown and described herein but intend to cover all such changes 
and modifications as are encompassed by the scope of the appended claims.