Servicing apparatus

• US 4,114,448 A
• Filed: 09/13/1976
• Issued: 09/19/1978
• Est. Priority Date: 09/13/1976
• Status: Expired due to Term

• Current Assignee: Joseph E. Merritt
• Original Assignee: Joseph E. Merritt
• Inventors: Merritt, Joseph E.
• Primary Examiner(s): Queisser, Richard C.
• Assistant Examiner(s): Beauchamp, John P.
• Application Number:
  US05/722,777
• Time in Patent Office: 736 Days
• Field of Search: 73/17 A, 73/339 R, 73/362 AR, 73/398 R, 62/125, 62/127, 62/129
• US Class Current: 62/129
• CPC Class Codes: G01D 3/02 with provision for altering or correcting the law of variation
• CPC Class Codes: G01K 1/143 for measuring surface temperatures
• CPC Class Codes: G01K 7/24 in a specially-adapted circuit, e.g. bridge circuit

Abstract

The disclosed apparatus is presented, for ease of comprehension, in terms of apparatus for servicing refrigeration systems, the disclosed apparatus using readily obtainable temperatures, rather than using the prior-art method of breaking into a refrigeration line for the purpose of measuring pressures.

An added feature is the ability of the apparatus to provide either absolute temperature read-outs for the temperature at the desired locations, or a differential temperature read-out for the temperatures between two desired locations. Moreover, the disclosed apparatus permits vacuum read-outs and pressure read-outs, again without the necessity of breaking into the refrigeration lines.

Since various refrigeration systems use different refrigerants, the disclosed apparatus also has the ability to convert the temperature read-outs to pressure read-outs that are associated with specific refrigerants.

In addition, the disclosed apparatus permits the automatic charging or bleeding of a refrigeration system that has an undercharge or an overcharge of refrigerant.

Claims

1. The combination comprising:

temperature-sensitive means, comprising a positionable probe, for producing a probe-signal corresponding to the temperature of the probe-environment having a known pressure/temperature relationship;

means for transposing said probe-signal to a temperature-signal;

means for transforming said temperature-signal to a temperature readout corresponding to the temperature at said probe-environment;

alternative means for electronically converting said temperature-signal to a pressure readout corresponding to the pressure at said probe-environment;

said converting means comprising means for synthesizing a pressure/temperature curve corresponding to said pressure/temperature relationship;

said synthesizing means comprising a set of generator means for synthesizing said pressure/temperature curve.

2. The combination of claim 1, including means, comprising selector-circuit means, for substituting a different set of generator means for synthesizing a different pressure/temperature curve corresponding to a different pressure/temperature curve corresponding to a different pressure/temperature relationship.

3. The combination comprising:

temperature-sensitive means, comprising a positionable probe, for producing a probe-signal corresponding to the temperature of the probe-environment having a known pressure/temperature relationship;

means for transposing said probe-signal to a temperature-signal;

means for transforming said temperature-signal to a temperature readout corresponding to the temperature at said probe-environment;

alternative means for electronically converting said temperature-signal to a pressure readout corresponding to the pressure at said probe-environment;

second temperature-sensitive means, comprising a second positionable probe, for producing a second probe-signal corresponding to the temperature at a second probe-environment having said known pressure/temperature relationship;

said transposing means comprising means for transposing said second probe-signal to a second temperature-signal;

said transforming means comprising means for transforming said second temperature-signal to a second temperature-readout corresponding to the temperature at said second probe-environment;

said converting means comprising means for converting said second temperature-signal to a second pressure-readout corresponding to the pressure at said second probe-environment;

said transposing means further comprising means for transposing said first probe-signal and said second probe-signal to a difference temperature-signal;

superheat-circuit means, activated by said difference temperature-signal, for producing a control signal;

said control signal being adapted to control the normalizing of a refrigeration system.

4. The combination for producing an output signal whose value is a function of an input signal in accordance with a preselected segmented curve, wherein successive segments of said curve are connected to each other at an end point common to said successive segments comprising:

means, comprising a plurality of segment generators, for synthesizing said segmented curve;

selected said segment generators being associated with a respective segment of said segmented curve;

each of said segment generators comprising means for causing a portion of its output waveform to have the same slope as its associated segment;

means for causing said portion of said output waveform of said segment generators to pass through the end-points of its associated segment.

5. The combination of claim 4, including means for causing the composite output waveform of said plurality of segment generators to include said segmented curve.

6. The combination of claim 5, including means for limiting the output waveforms of each of said segment generators to its associated segment.

7. The combination comprising:

temperature-sensitive means, comprising a first probe, for producing a first probe-signal corresponding to the temperature at a first probe-environment where there is a pressure/temperature relationship;

means for transposing said first probe-signal to a first temperature signal;

means for transforming said first temperature-signal to an absolute temperature-readout corresponding to the temperature at said probe-environment;

a second temperature-sensitive means, comprising a second probe, for producing a second probe-signal corresponding to the temperature at a second probe-environment where there is the same pressure/temperature relationship;

said transposing means comprising means for transposing said second probe-signal to a second temperature-signal;

said transforming means comprising means for transforming said second temperature-signal to a second absolute temperature-readout corresponding to the temperature at said second probe-environment;

said transposing means comprising means for transposing said first probe-signal and said second probe-signal to a difference temperature signal;

said transforming means comprising means for transforming said difference temperature-signal to a difference temperature readout;

superheat-circuit means, activated by said difference temperature-signal, for causing said superheat-circuit means to produce a control-signal;

whereby said control-signal may be used to control the automatic charging of a refrigeration system;

alternative means for converting said temperature-signals to pressure readouts corresponding to the pressures at said probe-environment;

said converting means comprising generator means for synthesizing a segmented waveform corresponding to said pressure/temperature relationship;

said synthesized segmented waveform having a plurality of segments, each of said segments having segment characteristics comprising a slope and end-points, adjacent said segments, having one substantially identical end-point;

said generator means comprising a like plurality of segment generators;

each of said segment generators comprising means for causing the slope of its synthesized segment to have the same slope as its associated segment, and means for causing its synthesized segment to pass through the end-points of its associated segment;

means for combining the synthesized output waveforms of said plurality of segment generators to form said synthesized segmented waveform.

8. The combination of claim 7, comprising means for substituting a different plurality of generator means for synthesizing a different pressure/temperature curve corresponding to a different pressure/temperature relationship.