Gauge device for measuring the inner diameter of engine related bores

#The present invention relates generally to a gauge device for measuring the inner diameter of engine related bores and more specifically a gauge device for measuring the crank pin bore of an engine connecting rod and the crank shaft main bore in an engine block.

#Heretofore calipers or caliper type devices have been provided for measuring the inner diameter of engine related bores. Typical of these prior devices are basic calipers in combination with a micrometer. The user spans the bore to be measured with a snap gauge then measures the snap gauge span with a micrometer. A further device uses calipers in connection with an attached dial indicator. Any movement in the caliper jaws causes a corresponding movement in the indicator.

#A disadvantage of taking measurements with caliper type devices and snap gauges is that the user must guess where to properly place the tips of the caliper and snap gauge to achieve an accurate measurement of the bore's diameter. This can result in the user inaccurately measuring a chord of the bore in lieu of its true diameter.

#In the drawings, which are discussed below, the same reference numerals refer to the same features of the invention throughout the drawings. A gauge device for measuring the inner diameter of engine related bores, according to the preferred embodiment of the invention is, shown in FIGS. 1-5.

#FIG. 1 represents an isometric view of the gauge device for measuring the inner diameter of engine related bores assembled in accordance with the principles of the present invention.

#FIG. 2 represents a side view of the gauge device for measuring the inner diameter of engine related bores, showing a cross sectional view of the circular body member, assembled in accordance with the principles of the present invention

#While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention, the invention will now be described by reference to the following description of preferred embodiment taken in conjunction with the accompanying drawings.

#Referring now to the drawings and particularly FIG. 1, there is shown an isometric view of the gauge device for measuring the inner diameter of engine related bores generally designated by the numeral 10 constructed according to principals of the present invention. The present device 10 in its broadest context, has as its components a circular body member 12 having a cylindrical chamber 22 with a slide pin housed within the cylindrical chamber 22, and a vertical slot 40 disposed on the front face 16. The device 10 is further defined by a top flange 34, and disposed equidistance to each side of the top flange 34 is a secondary flange 36. Additionally, the top flange 34 has a dial mount 48 which receives a dial indicator means 52. The indicator means 52 has a movable plunger 60 housed within a coil spring member 64 and extending downward until it abuts the plunger stop means 42.

#The circular body 12 has a diameter substantially less than that of the measured engine bore to allow the circumferential surface 14 of the circular body 12 to be inserted therein. In addition, the depth of the circumferential surface 14 of the circular body 12 is substantially less than that of the measured bore. Totally encased within the circular body 12 and along a longitudinal axis 26 is a cylindrical chamber 22 which extends through the circumferential surface 14 to create an upper 28 and a lower 30 opening as depicted in FIG. 2. Centered on the front face 16 and along said longitudinal axis 26 is a vertical slot 40 of substantial length which partially exposes the hollow cylindrical chamber 22 to the front face 16.