US3256685A

US3256685A - Time register arrangement for air compressors

Info

Publication number: US3256685A
Authority: US
Publication date: 1966-06-21
Anticipated expiration: 1983-06-21

Description

June 21, 1966 N. R. SIEWERT 3,256,685

TIME REGISTER ARRANGEMENT FOR AIR COMPRESSORS Filed Jan. 5, 1962 2 Sheets-Sheet 1 JNVENTOR. FIG. 2 NORMAN R SIEWERT Atfamy N. R. SIEWERT June 21 1966 TIME REGISTER ARRANGEMENT FOR AIR COMPRESSORS 2 Sheets-Sheet 2 Filed Jan. 5, 1962 INVENTOR. NORMAN R. SIEWERT United States Patent O 3,256,685 TIME REGISTER ARRANGEMENT FOR AIR COMPRESSORS Norman R. Siewert, Rochester, N.Y., assignor to Siewert Equipment Company, Inc., Rochester, N.Y., a corporation of New York Filed Jan. 5, 1962, Ser. No. 164,516 4 Claims. (Cl. 58--145) This invention relates to air compressors, and more particularly to means for recording the respective periods of time during which a compressor, or a series of compressors, operates to produce a given output pressure.

Today, there are many industries which rely upon compressed air for operating machines. One problem always is maintenance. In the dry-cleaning and laundry businesses, for example, one of the problems is timely anticipation of the need for checking and/or overhaul of the compression equipment. To properly anticipate this need and to thus avoid shutdowns, it is desirable to be able to ascertain readily at any time the number of hours at which a respective compressor has been operating, and more particularly, the number of hours during which it has been operating at various stages between zero and full capacity. When such information is not available, compressors are often permitted to operate for extended periods of time without receiving proper maintenance. I

A primary object of this invention is to provide means for recording accurately the total time of operation of a compressor.

Another object of this invention is to provide means for determining the time during which a compressoroperates at various loads between zero and full load.

A further object of this invention is to provide a means which is easily installable in an existing compressed air system for recording both total operating time and operating times at different loads of a compressor.

Other objects and features of the invention will be apparent from the following specification and the appended claims, particularly when read in conjunction with the accompanying drawings.

In the drawings:

FIG. 1 is a diagram illustrating a recorder made according to one embodiment of this invention and showing how this novel recording device may be inserted in a compressed air system;

FIG. 2 is a schematic view illustrating structure and wiring of the novel recording device, the portion at the left of the figure being a rear view of the front panel of the device and the portion at the right of the figure being a front view of the rear panel or cover of the device, the pressure switch of the device being cut away in part; and

FIG. 3 is a similar schematic view of a further embodi ment of the invention, the portion at the left being a rear view of the front panel of this recording device and the portion at the right being a front view of the rear cover or enclosure of the device.

Referring now to the drawings by numerals of reference, and first to the embodiment of the invention shown in FIGS. 1 and 2, 10 denotes a conventional air compressor, and 12 a motor for operating the same through a standard belt and pulley drive 13. Operation of motor 12 is controlled by a manually-operable conventional disconnecting switch 14 which may be closed to energize starter 16 for the motor. Air for the compressor is sucked through a conventional filter 20 and delivered through piping 22 to the intake side of the compressor. Air compressed by the compressor 10 is carried unidirectionally through the compressed air discharge pipe line 21 to a receiver or system reservoir 28, from whence it may pass through pipe 29 to the various machines or devices which are to' be operated by the compressed air.

The invention is particularly adaptable to a compressor of the type which employs conventional Free-Air Unloaders on each of the one or more inlet valves of the compressor. These unloaders are adapted to :be controlled in conventional manner by means of an auxiliary valve interposed between the unloaders and the compressed air reservoir. In FIG. 1, for example, one side of an adjustable auxiliary valve 25 is connected by means of pipe 27 to the reservoir 28, whereby said one side is always subjected to the system pressure. The other side a valve 25 is connected by means of pipe 24 to the one or more Free-Air Unloaders (not illustrated) on the compressor inlet valve or valves (not illustrated) that communicate with the air inlet pipe 22. Auxiliary valve 25 may be adjusted so that at a predetermined pressure of the air in reservoir 28, (usually the desired maximum system pressure) valve 25 will open to admit air from receiver 28 to pipe 24 and the Free-Air Unloaders. When the unloaders are thus placed under system pressure, they maintain the compressor air inlet valve or valves in open positions so that air is free to pass in and out of the valves without being compressed. In such instance the compressor runs -free-i.e., its piston continues to reciprocate but without compressing air. On the other hand, when the air pressure in reservoir 28 drops below the predetermined value, auxiliary valve 25 closes (such valves normally being loaded by an adjustable spring) to simultaneously close ofi reservoir 28 from the unloaders so that the unloaders permit the compressor inlet valves to function in normal manner. Assuming the system is designed for a maximum pressure of 100 pounds per square inch, auxiliary valve 25 is adjusted so that it opens when the air pressure in receiver 28 reaches 100 pounds per square inch. When valve 25 opens compressor 10 continues to run but. does not compress air. When the air pressure in reservoir 28 drops below 100 pounds per square inch the valve 25 closes, thereby relieving the pressure on the unloaders. Compressor 10 then begins once again to compress air thereby to raise the system pressure back to 100 pounds per square inch. The system thus far-described is conventional. v

The recorder or totalizer of the present invention is designated generally at 30. It is connected to the line 24 by means of piping 32 and to the electrical starter 16 by the electrical conductors or

wires

34, 35. The totalizer or recording device 30 includes two

time clocks

38 and 39, and a pressure switch 40. Time clock 38 records the number of hours during which the compressor is running under load (periods during which the compressor is actually compressing air) and time clock or hour meter 39 records the total number of hours during which the compressor is operating, whether under load or when running free.

Wire leads 34 and 35 from starter 16 are connected to the lower side of terminal block 44 (FIG. 2) of the recorder at

terminals

45 and 46, respectively. Through a wire jump in the block, terminal 45 (hence, wire 34) is connected to wire 47 which in turn is connected at 48 to one terminal of the electric motor for time clock 39. The other terminal 49 of this motor is connected by wire 50 to block 44, from whence it is connected by a wire jump to terminal 46 and to the other lead 35 from starter 16. Hence, whenever the motor 12 is running time clock or hour meter 39 will run, and will thus record the total operating time of compressor 10.

One terminal 52 of the motor which actuates time clock 38 is permanently connected through wire 53 to terminal 48 of the motor which actuates time clock 39.

The other terminal 54'of the motor for time clock 38 is connected by wire 55, terminal 56 of block 44, and wire 57 to terminal 58 of pressure switch 40. This switch includes a leaf spring blade 60 and relatively fixed off and on

terminals

61 and 62, respectively.

The pressure switch 40, as previously described, is connected by line 32 .to line 24. Line 32 supplies compressed. air from receiver 28 to one side of a flexible diaphragm 63, or a piston, bellows, Bourdon tube or other pressure sensitive device, whenever auxiliary valve 25 is open. This diaphragm carries a plunger 64 which engages the switch blade 60. When valve 25 opens, as the system reaches its maximum pressure, diaphragm 63 is subjected to system pressure so that plunger 61 moves and holds blade 60 in contact with terminal 61 which is dead-ended as at 67, thereby preventing the operation of clock 38. However, when the system pressure falls below a predetermined maximum, valve 25 closes and exhausts line 32 to the atmosphere so that the pressure in diaphragm 63 is decreased, thus permitting plunger 64 and the free end of spring switch blade 60 to move downwardly in the direction in which it is normally urged, to make contact with terminal 62 of pressure switch 40. Terminal 62 is connected by the wire or lead 66 and a jumper wire of the block 44 to line 35. Hence when blade 60 engages terminal 63 a circuit will be closed to clock 38 from line 34 through terminal 48 of clock 39, line 53, terminals 52 and 54, the motor of the time clock 38, line 55, terminal 56 of block 44, line 57, blade 60, terminal 62 of pressure switch 40, line 66, and block 44, to line 35. Thus time clock 38 will run as long as there is no system pressure on diaphragm 63 (auxiliary valve 25 closed), or in other words, as long as the system pressure is below a predetermined maximum and the compressor is under load and actually compressing air to elevate the system pressure once again to its predetermined maximum. The clock or hour meter 38 thus affords a permanent count or visual record of the time during which the compressor 10 is loaded (actually compressing air rather than running free), and hour meter 39 affords a record of the total time during which compressor 10 is running (under load or otherwise) FIG. 3 illustrates a further embodiment of the invention employing time clocks and pressure switches to record the total running time of the compressor and the individual running time of the compressor at various stages of its operation. By way of example, assuming a maximum system pressure of 100 pounds per square inch, four of the clocks will be employed to measure, respectively, the times during which the compressor is operating to elevate the system air pressure or the air pressure in receiver 28 to 94 pounds per square inch, from 94 pounds per square inch to 96 pounds per square inch, from 96 pounds per square inch to 98 pounds per square inch, and from 98 pounds per square inch to 1 pounds per square inch, respectively. Such operating times are analogous to operation of the compressor at full load, three-quarter, one-half, and one-quarter full load, respectively.

In FIG. 3, 30 denotes the recording unit or totalizer as a whole. This unit includes a plurality of time clocks 70, 71, 72, 73 and 74 for indicating, respectively, the total time of operation of the compressor (both running free and loaded) and the times of its operation under full, three-quarter, half, and one-quarter load. As in FIG. 2, the wire leads 34, 35 from starter 16 are connected to one side of a terminal block 44 and are jumped by wires to terminals 75 and'76, respectively, at the opposite side of the block. Compressed air is delivered from the system receiver, through four auxiliary valves (not illustrated) similar to the type described at 25 in FIG. 1, and into totalizer 30 by

pipes

77, 78, 79 and 80. These pipes deliver the compressed air against the diaphragms of pressure switches 82, 83, 84 and 85, respectively. Each of these switches has a diaphragm operated switch blade 60 and is similar to pressure switch 40 illustrated in FIG. 1. However, while the auxiliary valve associated with switch 85 is adjusted for a maximum system pressure of say 100 pounds per square inch, the auxiliary valves associated with switches 84, 83 and 82 are set or adjusted to close (thereby permitting the corresponding spring switch blade 60 to drop to its lower position) when the receiver or system pressure drops below say 98 pounds per square inch, say 96 pounds per square inch and say 94 pounds per square inch, respectively.

The time clock 70 records the total running time of the compressor 10, and hence is not associated with a pressure switch. Instead, this time clock is continuously in circuit with the motor through wire lead 34, block 44',

wire 86, one terminal 87 of the motor for time clock 74,

wire 88, one terminal 89 of the motor of clock 73, wire 90, one terminal 91 of the motor for time clock 70, through the motor to the opposite terminal 92 thereof, and back through wire 93 to terminal 76 of block 44', and through a wire jump to wire 35 to starter 16.

While clock 70 is continuously in circuit with motor 12, the motors for the remaining time clocks 71 to 74 are in circuit with starter 16 only upon the moving of their respective pressure switch blades 60 downwardly as their corresponding auxiliary valves close and

exhaust pipes

77, 78, 79 or 80 to the atmosphere. FIG. 3 is illustrative of the positions assumed by the pressure switch blades 60 (all up) when the receiver or system is under the maximum pressure of 100 pounds per square inch. At this time, one terminal for the motors in each of clocks 70 to 74 is connected, and remains connected, to starter 16 as shown by wire 34 which is connected through block 44' to wire 86, terminal 87 of the motor for clock 74, wire 88, terminal 89 for the motor in clock 73, wire 90, terminal 91 for the motor in clock 70, wire 94, terminal 95 for the motor in clock 71, and wire 96 to terminal 97 for the motor in clock 72. However, an open switch (described below) is interposed between each of the remaining terminals 98-, 99, 100 and 101 of the motor for clocks 74, 73, 72 and 71, respectively, whereby the latter four clocks are not running when the system is at 100 pounds per square inch. Instead, terminal 98 is connected through wire 103, terminal block 106, and wire 107 to the switch blade 60 in pressure switch 85, which blade is in engagement with the upper pressure switch terminal (comparable to terminal 61 in pressure switch 40). In pressure switch 85 the last-named upper terminal is dead-ended as at 67' so that the circuit between the motor terminal 98 in clock 74 and wire lead 35 to starter 16 is interrupted, thereby preventing the operation of clock 74. Similarly, the circuit between the motor termi nal 99 for clock 73 and the wire 35 leading from starter 16 is interrupted since terminal 99 is connected by wire 104, block 106, and wire 108 to the lower terminal in pressure switch 84 (comparable to terminal 62 in pressure switch 40), which lower terminal is elfectively dead-ended when the system is at maximum pressure because the switch blade 60 in pressure gauge 84 is in engagement with the upper terminal of switch 84 at such time. Thus clock 73 is not running. Nor is clock 72 running at this time either since it terminal 100 at this time is connected by wire through clock 106 to wire 109 and to the lower terminal of pressure switch 83, and switch blade 60 in switch 83 is out of contact with this lower terminal when the system is at maximum pressure. Likewise clock 71 is not running at this time since its motor terminal 101 is connected through wire 111, terminal 112 on block 44, and wire 113 to the lower terminal of pressure switch 82 which is out of engagement with switch blade 60 of switch 82 when the system is at maximum pressure.

However, when system pressure drops below 100 pounds per square inch, but remains above 48 pounds per square inch, switch blades 60 of switches 82 to 84 remain up, but blade 60 of switch 85 descends into engagement with the lower terminal of this switch 85 to thereby complete the circuit between the motor terminal 98 of clock 74 and starter 16 by means of wire 103, block 106, wire 107, switch blade 60 of pressure switch 85, the lower terminal of switch 85, wire 114, wire 115, the upper terminal' and switch blade 60 of pressure switch 84, wire 116, wire 117, the upper terminal and switch blade 60 of pressure switch 83, wire 118, wire 119, the upper terminal and switch blade 60 Olf pressure switch 82, wire 120, terminal 76 on block 44, and wire 35 to starter 16.

As the system pressure drops below 98 pounds per .square inch but remains above 96 pounds per square inch switch blade 60 of pressure switch 84 becomes disengaged from the upper terminal of switch 84, and drops to engage the lower terminal of switch 84 to complete the circuit from motor terminal 99 of clock 73 through wire 104, block 106, wire 108, lower terminal and blade 60 of pressure switch 84, wires 116 and 117, the upper terminal and blade 60 of switch 83, wires 118 and 119, the upper terminal'and blade 60 of the switch 82, wire 120, terminal 76 of block 44', and wire 35 to starter 16. Clock 74 is thus stopped, and clock 73 is started.

As the system \pressure falls below 96 pounds per square inch but remains above 94 pounds per square inch, switch blade 60 of pressure switch 83 drops, thereby interrupting the circuit for the motor in clock 73 and completing the circuit for motor terminal 100 of'clock 72 through wire 105, block 106, wire 109, the lower terminal and blade 60 of pressure switch 83, wires 118 and 119, the upper terminal and blade 60 of pressure switch 82, wire 120, terminal 76 on block 44', and wire ;.35 to starter 16. Clock 73 is thus stopped, and clock 72 is started.

,For system pressures below 94 pounds per square inch the switch blade 60 of pressure switch 82 drops from the upper tothe lower terminal of this pressure switch thereby interrupting the motor circuit for clock 72 and completing-the circuit from motor terminal 101 of clock 71 through wire 111, terminal 112 on block 44, Wire 113, the'lower terminal and blade 60 of switch 82, wire 120, and terminal 76 on block 44', and wire 35 to starter 16. Clock 72 is thus stopped and clock 71 is started.

From the foregoing it will be apparent that the four clocks 74, 73, 72 and 71 record the respective times during which the compressor is operating (actually compressing air in the system) against a system or discharge pressure of say from 98 to 100 pounds per square inch, 96 to 98 pounds per square inch, 94 to 96 pounds per square inch, and tfrom below and up to 94 pounds per square inch (gauge), respectively.

While the devices have been described in terms of decreasing air pressure in the system, it is apparent that as the pressure in the system increases from below- 94 to maximum (100 pounds per square inch) each of the hour meters 71, 72, 73 and 74 will be successively energized and then deenergized as the increasing pressure of the system successively opens their corresponding auxiliary valves. E.g., as system pressure increases beyond say 94 pounds per square inch, blade 60 of switch 82 is moved from the lower to the upper terminal of switch 82, thereby interrupting the motor circuit for hourmeter 71, and completing the circuit for the motor in hourmeter 72. This action does not start clocks 73 and 74 because the blade 60 in switch 83 is down, until system pressure exceeds 96 pounds per square inch.

Moreover, although the system illustrated in FIG. 3 is set to record quarterly stages of compressor operation, it is apparent that the invention will serve to record various fractional stages of compression depending upon the number of hourmeters and pressureswitches employed, and the manner in which their corresponding auxiliary valves are adjusted. For instance, in measuring three stage compression, the pressure switches and auxiliary valves may be connected to corresponding hourmeters, .the auxiliary valves being adjusted to operate at zero, onehalf and maximum compressor load, respectively. Moreover, although the invention has been described as utiliz- 6 ing auxiliary valves to control the operations of the various pressure switches, thereby affording a more instantaneous opening and closing of the switch blades 60 with the terminals in the various pressure switches, it is possible to eliminate the auxiliary valve and connect the pressure switches directly to .the receiver. In such instance the pressure switches will constantly be in communication with and responsive to the receiver pressure. When so connected and used to electrically energize and de-energize a three-way solenoid valve simultaneously with its respective time clock, the pressure switch acting in conjunction with the solenoid valve will replace the function of the auxiliary valve. Therefore, the various pressure switches will have to be of the conventional type which can be individually adjusted, or which are otherwise designed so that their respective spring blades 60 will be moved into engagement with the upper terminal of the respective pressure switch only when the diaphragm in the switch has been subjected to a predetermined system pressure.

While the invention has been described in connection with a specific embodiment thereof, it will be understood that it is capable of further modification, and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice in the art .to which the invention pertains and as may be applied to'the essential features hereinbefore set forth, and as fall within the scope of the invention or the limits of the appended claims.

Having thus described my invention, what I claim is:

1. The combination with (a) an air compressor, (b) an electrical motor for operating said compressor to supply air under pressure to a reservoir, (c) a valve-controlled air inlet foradmitting air to the compressor, ((1) a reservoir connected to the compressor for storing the compressed air, and (e) a valve connected to said reservoir to be opened when the pressure in said reservoir reaches a predetermined value, said valve, when open, permitting flow of the compressed air from the reservoir to said inlet so that air is free to pass in and out of the compressor without being compressed, (f) of apparatus for recording the duration of compressor operation at various stages of loading, said apparatus comprising (g) aplurality of time clocks,

(h) a circuit including a plurality of switches for selectively connecting said clocks respectively in parallel circuit with said motorfor operation therewith, each of said switches being interposed, respectively, in a circuit associated with one of said clocks,

(i) a plurality of pressure responsive elements for op- (1) means operative upon connection of one of said clocks .to disconnect the other clocks.

2. The combination with (a) an air compressor,

(b) an electric motor for driving the compressor,

(c) a valve-controlled air inlet for admitting air to the compressor,

(d) a reservoir connected to the compressor for storing compressed air, and

(e) a valve connected to said reservoir to be opened when the pressure in said reservoir exceeds a pre- 7 determined value, said valve, when open, permitting flow of the compressed air from the reservoir to said inlet so that air is free to pass in and out of the compressor without being compressed, (f) of a plurality of electrically-operated time clocks, (g) means continuously connecting a first clock in parallel circuit with said motor to operate when said motor operates, thereby to record the total operating time of said compressor,

(h) means including a pressure-operated switch movable from a first position .to a second position for connecting and disconnecting, respectively, a second time clock into and out of parallel circuit with said motor, and

(i) means conecting said switch to said valve so that when said valve is open said switch is moved to its second position to disconnect said second time clock from the circuit and when said valve closes said switch moves to its first position to connect said second time clock in circuit to record the runing time of the compressor under load.

3. The combination with (a) an air compressor,

(b) an electric motor for driving the compressor,

(c) a valve-controlled air inlet for admitting air to the compressor,

(d) a reservoir connected to the compressor for storing compressed air, and

(e) valve means connected to said reservoir to be opened when the pressure in said reservoir exceeds a predetermined value, said valve means, when open, permitting flow of the compressed air from said reservoir to said inlet so that air is free to pass in and out of said reservoir without being compressed,

(f) of more than two time clocks,

(g) a separate-pressure operated switch associated with each time clock, each pressure operated switch being movable from a first position to a second position for connecting and disconnecting, respectively, the associated time clock into and out of parallel circuit, respectively, with said motor, the separate switches being connected to said reservoir and being adapted, respectively, to be held in their respective second positions when said reservoir is at respectively diflferent pressures, each switch being constructed to move to its respective first position only when the pressure in said reservoir drops below said predetermined value to a respective given pressure which is different for each switch, whereby at a given time only those switches will be in their respective first positions, to which the pressure applied is insufficient to hold them in their respective second positions, said switches being so connected together electrically that only that switch, which is in its first position and moves to such first position at the lowest given pressure then prevailing in the reservoir will close a circuit to its associated time clock, whereby only one of the time clocks associated with said switches will be in circuit at a time, thereby to record the time of operation of the compressor at the pressure at which the respective associated switch is in its first position.

4. A combination as claimed in claim 3, wherein (a) an additional time clock is provided, and

(b) means is provided continuously connecting said additional time clock in parallel circuit with said m0- tor to operate when said motor operates, thereby to record the total operating time of the compressor.

References Cited by the Examiner UNITED STATES PATENTS 1,340,324 5/1920 Buck 58-146 1,414,910 5/1922 Watson 58-146 X 1,475,831 11/1923 Johnson et al 58-147 1,566,290 12/ 1925 Swift 58-395 2,501,960 3/1950 Olson 58-39.5 X 2,679,038 5/1954 Cross et a1. 58- X LEO SMILOW, Primary Examiner.

H. R. MOSELEY, Examiner. C. I. BORUM, G. F. BAKER, Assistant Examiners,

Claims

1. THE COMBINATION WITH (A) AN AIR COMPRESSOR, (B) AN ELECTRICAL MOTOR FOR OPERATING SAID COMPRESSOR TO SUPPLY AIR UNDER PRESSURE TO A RESERVOIR, (C) A VALVE-CONTROLLED AIR INLET FOR ADMITTING AIR TO THE COMPRESSOR, (D) A RESERVOIR CONNECTED TO THE THE COMPRESSOR FOR STORING THE COMPRESSED AIR, AND (E) A VALVE CONNECTED TO SAID RESERVOIR TO BE OPENED WHEN THE PRESSURE IN SAID RESERVOIR REACHES A PREDETERMINED VALUE, SAID VALVE, WHEN OPEN, PERMITTING FLOW OF THE COMPRESSED AIR FROM THE RESERVOIR TO SAID INLET SO THAT AIR IS FREE TO PASS IN AND OUT OF THE COMPRESSOR WITHOUT BEING COMPRESSED, (F) OF APPARATUS FOR RECORDING THE DURATION OF COMPRESSOR OPERATION AT VARIOUS STAGES OF LOADING, SAID APPARATUS COMPRISING (G) A PLURALITY OF TIME CLOCKS, (H) A CIRCUIT INCLUDING A PLURALITY OF SWITCHES FOR SELECTIVELY CONNECTING SAID CLOCKS RESPECTIVELY IN PARALLEL CIRCUIT WITH SAID MOTOR FOR OPERATION THEREWITH, EACH OF SAID SWITCHES BEING INTERPOSED, RESPECTIVELY, IN A CIRCUIT ASSOCIATED WITH ONE OF SAID CLOCKS, (I) A PLURALITY OF PRESSURE RESPONSIVE ELEMENTS FOR OPERATING SAID SWITCHES, EACH OF SAID ELEMENTS BEING INTERPOSED BETWEEN SAID RESERVOIR AND ONE OF SAID SWITCHES, (J) SAID ELEMENTS BEING CONNECTED TO SAID RESERVOIR AND BEING OPERATIVE WHEN THERE IS A PREDETERMINED PRESSURE IN SAID RESERVOIR TO CAUSES SAID SWITCHES TO DISCONNECT ALL SAID CLOCKS FROM SAID MOTOR, (K) EACH OF SAID ELEMENTS BEING OPERATIVE AT RESPECTIVELY DIFFERENT PRESSURES BELOW SAID PREDETERMINED PRESSURE TO CAUSE THE RESPECTIVE CORRESPONDING SWITCH TO CONNECT THE CLOCK ASSOCIATED THEREWITH IN CIRCUIT WITH SAID MOTOR, AND (L) MEANS OPERATIVE UPON CONNECTION OF ONE OF SAID CLOCKS TO DISCONNECT THE OTHER CLOCKS.