Compressor intercooler unloader arrangement

A method of rapidly exhausting air pressure from an intercooler when an air compressor driven by a multi-speed power means and having a different number of magnetic poles pneumatically connected to said intercooler is unloaded, said multi-speed power means being capable of changing speeds within a substantially short period of time when one set of magnetic poles is activated and another set is deactivated, the method comprising the steps of:

• (a) sensing an air pressure in an at least one reservoir supplied by said air compressor;
• (b) initiating unloading of said air compressor when said air pressure present in said at least one reservoir reaches a preset level;
• and
• (c) operating an electrically operated valve pneumatically connected to said intercooler and electrically connected to a means for sensing said air pressure in said at least one reservoir to initiate unloading of air pressure from said intercooler when within the short period of time for changing the speed of said power means said electrically operated valve receives an unload signal from said pressure sensing means.

Apparatus for rapidly unloading air pressure in an intercooler when a compressor pneumatically connected to said intercooler is unloaded, comprising:

• a governor pneumatically connected to at least one reservoir tank connected to receive pressurized air from the compressor,
• said governor having pressure sensing means operable to order unloading of the air compressor when air pressure level in said tank reaches a preset value,
• an electrically operated valve connected pneumatically to the intercooler and connected electrically to the pressure sensing means of said governor,
• said electrically operated valve being effective to exhaust the air pressure in said intercooler to atmosphere when said valve receives an unload signal from the pressure sensing means, and
• an electrical motor having a different number of magnetic poles that provide different motor speeds when one set of magnetic poles is activated and another is deactivated under control of a system for providing the motor with electrical current, with the sensing means of said governor electrically connected to the control system of said motor for ordering the compressor to unload when transition of the motor from operating at one speed configuration to operating at another speed configuration occurs,
• said transition occurring in a substantially short time period, with the valve being effective to unload intercooler air pressure during the short time period of said motor transition.

An intercooler/compressor arrangement wherein the intercooler of the arrangement supplies low pressure air to a high pressure cylinder of the compressor and wherein the compressor is driven by an electrical motor having at least two different speed configurations and a control system for respective energization of the two speed configurations, the arrangement comprising:

• a governor pneumatically connected to at least one reservoir tank connected to receive pressurized air from the compressor, said governor having pressure sensing means operable to order unloading of the air compressor when air pressure level in said reservoir tank increases to a preset value, and
• an electrically operated valve connected pneumatically to the intercooler and connected electrically to the sensing means of said governor,
• said sensing means, in addition, being connected to the control system of the electrical motor for ordering transition of the motor from operating at one speed configuration to operating at the other speed configuration, said transition occurring in a relatively short period of time, and
• said electrically operated valve being effective to exhaust air pressure in the intercooler to atmosphere during the time period of motor speed transition when the electrically operated valve receives an unload signal from said sensing means.