초록 ▼

A diagnostic instrument detects and locates malfunctions in a pneumatic circuit of the kind which controls a transmission in response to movement of an operator\s shift lever. One or more connectors enable simultaneous coupling of a plurality of pneumatic signal lines with various key flow paths of

A diagnostic instrument detects and locates malfunctions in a pneumatic circuit of the kind which controls a transmission in response to movement of an operator\s shift lever. One or more connectors enable simultaneous coupling of a plurality of pneumatic signal lines with various key flow paths of the transmission control circuit. The signal lines extend through a cable to an instrument housing containing a pressure indicator and having a plurality of test valves for sequentially connecting individual ones of the signal lines to the indicator whereby the presence or absence of pressure at various key points in the control circuit may be quickly determined. As the pressures to be detected may be transitory in certain parts of the circuit, means are provided for maintaining the indicator in the pressure indicating condition following a momentary sensing of pressure and reset means are provided for restoring the indicator following testing of each particular flow path so that a subsequent flow path may then be tested. Means are also provided for directing compressed air to any selected one or ones of the circuit flow paths through the test instrument independently of the operator\s shift control. Gages are also present on the instrument for determining the exact value of pressures at selected points in the control circuit.

대표청구항 ▼

Apparatus for testing a pneumatic circuit that has a pressurized fluid supply and a plurality of fluid flow paths which are individually pressurized from said supply in predetermined combinations to control a plurality of pneumatic devices in a transmission, comprising: a test pressure conduit, pres

Apparatus for testing a pneumatic circuit that has a pressurized fluid supply and a plurality of fluid flow paths which are individually pressurized from said supply in predetermined combinations to control a plurality of pneumatic devices in a transmission, comprising: a test pressure conduit, pressure sensing means for indicating the presence or absence of a predetermined degree of pressure in said test conduit, a plurality of pneumatic signal lines, a plurality of test valves each being coupled between said test pressure conduit and an individual one of said pneumatic signal lines, connector means for temporarily coupling individual ones of said signal lines with separate individual ones of said flow paths of said circuit which is to be tested, a pressurized fluid supply line, connector means for selectively coupling said fluid supply line to said pressurized fluid supply independently of said pneumatic circuit to be tested, and a pressure test valve connected between said fluid supply line and Said test pressure conduit whereby said testing apparatus may be operated to selectively pressurize ones of said pneumatic signal lines.