US2563765A

US2563765A - Lubricating apparatus

Info

Publication number: US2563765A
Application number: US670467A
Authority: US
Inventors: Wedeberg Reuben
Original assignee: Stewart Warner Corp
Current assignee: Stewart Warner Corp
Priority date: 1946-05-17
Filing date: 1946-05-17
Publication date: 1951-08-07
Anticipated expiration: 1968-08-07

Description

R. WEDEBERG LUBRICATING APPARATUS Aug. 7, 1951 Filed May 17, 1946 4 Sheets-Sheet l Elfman/u ILMLE 130 '"LImi Q Immun Aug. 7, 1951 R. WEDEBERG LUBRICATING APPARATUS 4 Sheets-Sheet 2 Filed May 17, 1946 Aug' 7 1951 R. WEDEBERG 2,563,765

LUBRICATING APPARATUS Filed May" 17, 1946 4 sheets-sheet 5 f J0@ A C f4? C 78 7 w Q w 152 151 39 A .ZQ 8j 66 85 96 AKR OPEFZATED LUBRICANT L comprzesso u I f fp f/ 121 flcweJ/ZJ': f/f ,/L'a/e//bede/ajg,

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Aug- 7, 1951 R. wem-:BERG 2,553,765

LUBRICATING APPARATUS Filed May 17, 194e 4 Sheets-Sheet 4 zo@ g ZZ9*" az /ZZZ Zfff ZZ 1Z0) l@ IV r A i zzf wel/Z514- fgeu/aez/z/ Mede/0,9137.

Patented Aug. 7, 1951 UNITED STATES PATENT OFFICE 9 Claims.

This invention relates to lubricating apparatus, and more particularly to centralized lubricating systems in which a plurality of measuring valves are periodically supplied and actuated from a single source.

One object of the invention is to provide a new and improved timing mechanism for automatically initiating the operation of such a lubricating system at predetermined intervals.

Another object of the invention is to provide a timing mechanism for controlling the duration of each period of operation of the system.

A further object of the invention is to provide a timing mechanism which is readily adjustable to vary the frequency of operation of a centralized lubricating system.

It is also an object of the invention to provide a timing mechanism which is readily adjustable to vary the duration of each period of intermittent operation of a centralized lubricating system.

An additional object of the invention is to provide a centralized lubricating system with a control mechanism which automatically initiates the operation of the system at predetermined intervals for supplying lubricant under pressure throughout the system, and to provide as a part of the control mechanism, a warning; signal which is automatically actuated in the event of the failure of pressure or exhaustion of the lubricant.

Other objects and advantages of the invention will appear from the following description taken in connection with the drawings, in which:

Fig. 1 is a front elevation of the control apparatus for a lubricating system including the timing mechanism which is the subject of this invention;

Fig. 2 is a rear elevation of the control mechanism;

Fig. 3 is a face View of the frequency cam disc of the timing mechanism and its masking disc in assembled relation;

Fig. 4 is a face view of the masking disc alone;

Fig. 5 is a face View of the duration cam disc and its masking disc in assembled relation;

Fig. 6 is a face view of the masking disc for the duration cam;

Fig. 7 is a sectional view taken diametrically through the frequency cam, the duration cam and their masking discs as assembled on their co-axial drive shafts in the timing mechanism.;

Fig. 8 is a diagrammatic view of the lubrication system of the dual type with a wiring diagram of the timing mechanism as associated therewith for controlling the system;

Fig. 9 is a diagrammatic view of a centralized lubricating system of the single line type, together with a wiring diagram of the timing mechanism as associated therewith for controlling the system.

There are various types of centralized lubri- 2 cating systems -by which lubricant is distributed to a plurality of bearings or other surfaces requiring lubrication, in which distribution occurs intermittently but preferably at regular intervals. In such systems, each bearing or other point requiring lubrication is -tted with a measuring valve and these valves are connected together by conduits by which they are each filled with a predetermined quantity of lubricant. Then by application of pressure to the lubricant in the connecting conduits, the valves are actuated to discharge their lubricant to the individual bearings. In a single line system, the measuring valves are connected in a series and the pressure is applied in one direction only, from the pump or other source of pressure through the system to the last valve of the series. In a dual line system, the measuring valves are connected in a closed series or loop which extends from the pump or compressor and returns to it so that pressure may be applied through the series in either direction. In these dual systems, each measuring valve is filled by the application of pressure to the system in one direction and is then discharged by the application of pressure in the opposite direction. A complete operation of the system usually consists in the application of pressure rst in one direction, causing each of the valves to deliver a charge of lubricant previously acquired and at the same time renlling another chamber of the valve with lubricant; the operation is then completed by reversing the pressure through the system causing each of the valves to deliver the charge of lubricant just acquired and to be relled for a subsequent operation. Since each valve delivers two charges of lubricant at each operation of the system, such a valve may have connections to two different bearings to be lubricated successively during the complete cycle of operation. In the single line system, a single application of pressure delivers a charge of lubricant from each of the valves and then refills the valves in preparation of the next periodic operation of the system.

Either system may be operated manually and at will at intervals depending upon the judgment of the operator, but in many cases it is preferable that the intermittent operation be automatically controlled and timed, and this is the function of the mechanism embodying this invention. The timing mechanism disclosed herein is claimed in divisional application Serial No. 12,807, filed March 3, 1948 and entitled Timing Mechanism.

In Figs. 1 and 2, the timing mechanism is shown associated with valve devices intended for operation of a dual line system, and Fig. i shows such a system diagrammatically. The control devices are supported on a panel board I6 and the timing mechanism is actuated by an electric clock l2, preferably driven by a synchronous twenty-four hours.

3 'motor and having the usual shafts t4 and I6 telescopically arranged as indicated in Fig. '7.

an hour hand, the shaft I4 carries the frequency cam disc I3, and instead of a minute hand, the

shaft I3 carries the duration cam disc 20. Each of said discs has peripheral notches or recesses for actuating electric switches, and the frequency cam I8 has associated with it a masking disc I9, while the duration cam 28 has associated with it a masking disc 2|, said masking discs determining which of the recesses or notches of the cams shall beoperative at any given time.

The frequency cam I8, as shown, has twelve notches or recesses 22 spaced at equal intervals so that a stationary follower element cooperating therewith may be actuated every two hours as the cam I8 rotates. f theV lubricating system is to be operated at two hour intervals, the masking disc I9, which is mounted co-axially with the disc I8, will be rotatively adjusted to uncover all the recesses 22, but if operation at less frequent intervals is desired, the disc I9 may be shifted so that certain portions of its periphery will cover certain of the notches 22, leaving less than twelve of them effective for actuating such a follower. As shown in Fig. 3, the disc I9 is adjusted to uncover only three of the notches 22, thus providing for operation of a lubricating system at eight hour intervals. The masking disc I9 is formed as shown in Fig. 4 with peripheral recesses so arranged thatit can be adjusted with respect to the disc I8 so as to provide for operation of the system either at two hour intervals, at four hour intervals, at eight hour intervals, at twelve hour intervals or only once in each twenty-four hours.

As shown in Fig. '7, the frequency cam disc I8 is secured rigidly to a hub 23 which is fixed to the hollow shaft I4 by a set screw 24. The masking disc I9- is rotatably mounted on the hub 23 but is held in face to face contact with the cam disc I9 by means of a coil spring 26 on the hub. A small boss or detent projection 29 on the face of the disc I9 is adapted to fit in any one of the five openings 28 in the disc I8, and as shown in Fig. 3, said openings are marked respectively with the numerals 24, I2, 2, 8 and 4 to designate the intervals at which the system will be operated when the masking'disc is adjusted with its detent projection 29 in any one of said openings 28. Tofacilitate such adjustment, the masking disc is provided with diametrically projecting lugs 3|] by which it may be grasped between the thumb and finger and forced away from the disc I8 (against the pressure of the spring 26) to release the projection 29 from one of the openings 28, and then rotated to register the projection with another opening 28.

The duration cam disc 20, as shown in Fig. 5, has a series of'peripheral notches or recesses 32 which differ in circumferential extent and correspond respectively to periods of one to ve minutes for active operation of a lubrication system. In other words a followerdevice which controls operation of the system drops into one of the notches 32 and the system continues to operate until the follower is cammed out of the notch. To determine which of the notches 32 shall be effective, the masking disc 2 I, which is associated with the cam disc 20, has a plain peripheral por- 4 tion v'34 and a single notch 3|, which is of the same width as the widest of the notches 32. By rotative adjustment ofthe disc 2 I, this notch 3| may be registered with any of the several notches 32 so as to expose a selected one of them while the plain circular portion 34 of the disc 2| covers the remaining notches 32. For a special purpose, to be later explained, the masking disc 2| has an additional notch 35 with its leading edge 35a disposed diametrically opposite the middle of the notch 3|; and a corresponding portion 31 of the periphery of the cam disc 20 is of reduced diameter so as to expose or uncover the notch 35 at any of the several positions of adjustment of the masking disc with respect to the cam disc. At each of these positions of adjustment, the notch 3| is centered with respect to the notch 32 which it exposes; consequently the leading edge of the notch 35 is always disposed diametrically opposite the uncovered notch 32 so that the follower of a v control device positioned to engage in the notch 35 will do so at the middle of the timing period represented by the active or exposed notch 32.

The cam disc 20 has an opening 38 opposite each of the notches 32 and the masking disc 2| has a small boss or projection 39 adapted to enter any one of the openings 38 when the disc 2| is suitably adjusted about its axis. As seen in Fig. 7, the disc 2| is fixed to a hub 33 which is secured to the shaft I6 by a set screw 34 and the coil spring 39 on said hub presses the cam disc 20 into face to face contact with the disc 2 I. The cam disc is rotatable on the hub and is provided with lugs or finger pieces 40, by which it may be pulled forward out of contact with the disc 2|, so as to release the detent boss 39 from one of the openings 38 and permit rotation of the disc 2| to register the boss with any other opening 38. In Fig. 5 the openings 38 are marked respectively IM, 2-M, 3-M, 4-M and 5-lVI to indicate that the notches will effect operation of the system for periods of from one to ve minutes respectively, and as shown, the detent 39 is registered in the opening 38 corresponding to the three minute period.

Since the cam discs. I8 and 28 are similar in size and the disc 2|) and its masking disc 2| are located in front of the surface of the frequency cam I8, the

discs

20 and 2| are provided with segmental windows 4| and 42 which may be reg-` istered with each other, and then rotated into registration with the openings 28 Vof the disc I8 as shown in Fig. 1. This permits adjustment of the masking disc I9 to the desired position after which the

discs

20 and 2| may be adjusted relative to each other as desired. Y

In addition to the clock I2 and the timing cams just described, the panel Ii] supports three switches 5|), 60 and 10 which may be of the microswitch type having actuating arms 5I, 6I, and 'II respectively, extending for engagement with the cam discs. These switches control the supply of current to solenoids which are mounted on the rear face of the panel I0 as seen in Fig, 2, and which are designated respectively by the numerals 8|, 82, 83 and 84. The plungers of solenoids 8| and 82 are aligned and connected together for simultaneous movement, and similarly the plungers of

solenoids

83 and 84 are aligned and connected together. Solenoids 8| and 82 are thus arranged to actuate a lever 85 which is fulcrumed to extend through the panel board I0 and is connected to the stem 86 of a valve 8'I for-actuatingit. Similarly the

solenoids

83 and 84 are connected to a lever 88 which is fulcrumed in the panel board I0 and which actuates the stem 89 5. of a valve 90. The

valves

81 and 90 may be spool valves or slide valves of any suitable internaly design and are diagrammatically illustrated in Fig. 8. A lubricant supply pipe 9| extends to a T-tting 92 having branches 93 and 94 connected to the

valves

81 and 90 respectively. The valve 81 has a feed pipe 95 for connection with one end of the lubrication system, and the valve 90 has a feed pipe 99 for connection with the other end of the system. A vent pipe 91 is shown extending from the valve B1 and the vent pipe 98 extends from the valve 90.

In Fig. 8 the diagram shows the supply pipe 9| leading from the air operated lubricant compressor atv |00, while the vent or return

pipes

91 and 98 lead from the

valves

81 and 90 to said compressor. The feed pipe 95 is shown leading from the valve 81 to a series of measuring valves |02 which operate as already described and each of which is provided with two outlet tubes |04 and |05 which may lead to separate bearings, or which in some cases may both lead to the same bearing if it is of a character requiring an unusual amount of lubrication. Conduits |08 of tubing connect the valves |02 and the final valve of the series is connected by the pipe 96 to the control valve 99 on the panel board I0. The air motor for operating the compressor at |90 is not shown in detail in the drawings, but compressed air for actuating it may be understood as being supplied through the pipe |91 which leads from a valve |98 having and air pressure supply pipe |09 and a Vent pipe H; the valve is shown with a solenoid H2 for actuating it. The solenoid I I2 and the air valve |08 are seen in Fig. 2 mounted on the rear face of the panel board |0.

From the previous explanation, it will be understood that the function of the timing mechanism and the

valves

81 and 90 is to initiate the operation of the compressor |00 at predetermined intervals and then to maintain such operation for a predetermined period of from one to five minutes during which period the lubricant is first fed out through the pipe 95 and through the series of measuring valves |92, until all said valves have been discharged and relled, whereupon a portion of the lubricant will flow through the pipe 95 and valve 90 back to the compressor by Way of the return pipe 98. Then the

valves

81 and 90 will be reversed to cause an outflow of lubricant through the pipe 98 and measuring valves |02 and back by way of the pipe 95, valve 81 and return pipe 91. The manner in which this is accomplished 'by the timing mechanism may be best understood by reference to the wiring diagram in Fig. 8. The current supply is furnished by lead wires |20 and 2| controlled by a main switch at |22, and when the switch |22 is closed, the clock |2 is energized through conductors |24 and |25. Whenever an exposed notch 22 of the frequency cam i8 registers with the follower 5| of the switch 50, the switch is closed at the contact 52 from which a conductor 53 leads to the contact point 62 of the switch 60. While the follower is still engaged in the notch of the frequency cam I8, the follower 6| of the switch 60 engages in the exposed notch 32 of the duration cam and thus causes the switch 69 to close at contact E2. Since the switch is connected by conductor 54 with the main lead wire |2I, this completes a circuit from switch through conductor 63, solenoid |2 and conductor 84, which is connected with the other lead wire |20.

The switch 60 is also connected by a conductor 13 to the solenoids 8| and 84. The circuit through said solenoids is completed by conductors 14 and 15, the latter being connected to the lead wire |20. i

With the solenoids thus energized, the valve members of the

valves

81 and 90 will be positioned as shown in Fig. 8 and since the solenoid- ||2 has been simultaneously energized, the air operated lubricant compressor at |00 will be furnishing lubricant under pressure through the pipe 9| and branch 93 to the chamber of the valve 81, and then by way of pipe 95 to the measuring valves |02 of the system. The time required for the lubricant to actuate all the valves |02 in the system and complete its circuit back to the valve and Vent or return pipe 98 will have been determined, and the operative notch or recess 32 of the duration cam will have been selected in view of this determination. By the time the lubricant has completed its circuit, the cam 20 will have advanced through about one-half of the length of the notch 32 and the follower 1| will then drop into the notch 35 in which it will ride for the remainder of the period. With the follower 1| in this position, the arm of the switch 10 will be shifted from contact 12 to contact 1B which is connected by the conductor 11 with solenoid 83 and by conductor 18 with solenoid 82. The separation of the switch arm from contact 12 will deenergize the solenoids 8| and 84, and its engagement with contact 16 will then energize

solenoids

83 and 92, causing reversal of the valves 01 and 90. Thereupon the lubricant, being supplied under pressure through the pipe 9| and branch 94, will iiow from the valve 90 through theV pipe 98 and thence through the several measuring valves |02 of the system, returning by way of pipe 95, valve 81 and Vent pipe 91 to the comprersor at |00.

As the cam disc 20 continues to turn, the follower El will ride out of the notch 32, disengaging the arm of the switch 60 from the contact 62 and breaking the circuit of the solenoid |112, thus permitting the air valve |98 to shift into a position at which the air pressure is cut oil from the air motor which operates the lubricant compressor |00. Thereupon the pressure in the system is vented through the pipe 91 and no further delivery of lubricant is effected for the time being. The continued rotation of the cam disc I8 causes the follower 5| to ride out of the notch 22 and to open the switch 50 which then remains open until the next effective notch 22 of the disc I8 registers' with the follower 5 I.

Fig. 8 shows a branch pipe |30 leading from the supply pipe 9| to a pressure responsive device |3| which consists of a cylinder containing a spring pressed piston having a stem |32 which protrudes slidably from the end of the cylinder. If a satisfactory pressure is developed in the pipe 9| by the operation of the compressor at the beginning of a lubrication period, the stem |32 will be protruded suiciently to disengage the arm of switch |49 from the contact I4 However, if this should not occur, either because the supply of lubricant available to the compressor |09 has been exhausted or because the compressor is not functioning properly, the engagement of the follower 1| in the notch 35 will establish a circuit through a relay switch |42 for lighting a red warning signal lamp |43 and actuating an audible signal |44,

Thus if the operation of the system proceeds normally, causing pressure to be built up in the pipe |30, the switch |40 will be opened before the second half of the cycle in which the follower 1| engages the notch 35 of the duration cam 20, and the green signal light |5| will burn continuously; but if satisfactory pressure fails to be attained in the rst half of the period controlled by the duration cam 20, the pressure responsive stem |32 Will not be lifted and the switch |40 will remain closed, thus permitting the relay switch |42 to be unlatched and to energize the warning signals |43 and |44. The switch |42 will then remain unlatched so that the red light will continue to burn and the horn will continue to sound until the switch |42 is manually reset, thus requiring the operator of the machine or apparatus to give it attention and determine the cause of failure of the lubrication system.

As another example of the use of the timing mechanism embodying this invention, Fig. 9 illustrates diagrammatically a portion of a single line centralized lubricating system and includes a wiring diagram of the control devices actuated by the timing mechanism. In this case the system is shown as having a lubricant compressor 200 driven by an electric motor 20| and having a supply pipe 202 leading from any suitable source of lubricant supply, with a feed pipe 203 leading to a series of measuring valves 204. Connecting conduits 205 extend between successive valves of the series, but there isno return connection as in the case of the system shown in Fig. 8. Admission of lubricant under pressure to the valves 204 is controlled by any suitable form of valve, which is indicated diagrammatically at 200 on Fig. 9. This valve is connected to the line 203 by a branch pipe 201 so that when the valve is open, the line 20.3 is vented through the vent pipe 208 which leads from the valve 200,. If the valve is closed, the vent 208 is closed and pressure developed in the ,line 203 is transmitted to the measuring valves 204.

The timing mechanism consists of the clock i2, the frequency cam |8 and the duration cam 20 as in vthe structure already described. The supply of electrical energy is obtained through the main lead wires |20 and |2| under control of the main switch |22, and when the switch i252 is closed, the clock |2 is connected into a circuit comprising conductor 209, conductor 2|0 and conductor 2| I. VThe clock then continues to run and when the follower 5| engages a notch in the frequency cam l0, the arm of the switch 50 engages contact 52 from which the conductor 53 leads to the arm of switch 60. The switch 50 is connected to lead wire i2! by conductor 2 |2. 1n this arrangement the switch 50 is a double throw switch and its arm normally engages a contact 2|3 from which the conductor `2|4 leads to the solenoid coil 2i'5; from this coil the circuit is completed through conductor 2|6 and lead wire |20. f As soon as the follower 6| engages a notch in the duration cam 20, the arm of switch 50 is separated from contact 2 3, thus opening the circuit of solenoid 2|5. The switch arm then engages Contact 2i'l from which conductor 2|8 leads to the coil 2|@ of a relay switch 220, which controls the driving motor 20 for the pump 200. From the

coil

2,10, conductors 22| and 222 complete the relay circuit by connection with the lead wire l The switch 220 is connected by conductor 223 with the conductor 2 leading from the feed Vwire |25, and the contactV point 224, which the arm of the switch 220 engages is connected to the motor 20| by conductor 225; the niotor circuit is completed by

conductors

225 and 222 leading to the feed wire |20.

In addition to starting the motor 20|, the closing of the relay switch 220 energizes the solenoid 221 which is connected to the contact point 224 of the switch by conductors 22E and 229, the circuit for the solenoid being completed through conductor 2id and lead wire 520. Thus simultaneously with the starting of the pump 200, the valve 202 is closed by the solenoid 221 so that pressure generatedl by the pump will be transmitted through the line 203 to the measuring valves 204. The pump 200 continues to operate until the follower 0| rides outer" the notch in the duration cani 20, whereupon the arm of switch e0 is disengaged from the contact 2|1, thus opening the motor circuit and also opening the circuit of solenoid 221, while engagement of the arm with contact 2|S closes the circuit of solenoid 2 5 and shifts the valve to its venting position.

A branch pipe 230 is connected into the pres'- sure line 203 and is fitted with a pressure responsive device comprising a cylinder 22| with a stem 232 adapted to be protruded by the application or. pressure through the pipe 230. During the nrst half of the operating period determined by the cam 20, the pressure in the line 203 should build up suiciently to protrude the stem 232 and open the switch |40 which is connected by a conductor 233 with the contact point 234. After the first half of the operating period, the follower 1| will occupy the notch 35 in the masking discv of the duration cam 20,thus bringing the switch arm 10 into engagement with the contact point 234. lThe switch 'l5 is connected by a conductor 235, conductor 228, relay switch 220 and conductor 2|| to the lead wire l2|, and if the pressure built up in the line 203 and branch line 230 is insufficient to open the switch |40, a circuit will be completed from the switch "l0 through conductor 233, switch arm |40, contact |41, conductor |45, relay coil 45, conductor |47 and conductor 222 to the lead wire |20. The latching relay |42, identical with that already described, normally maintains its switch arm in engagement with the contact |49 which is connected by conductor |50 with a green signallamp I5 l. The relay switch |42 is connected by conductor |48`t0 conductor 2| and then to the lead wire `9 |2.|. |41 and 222 to the lead wire `lf2-0,; hence the circuit for the green lamp `i is normallyclosed through the relay |42 whenever the main Vswitch |22 is closed. But the energizing of the coil |45 withdraws the latch |52 from the relay switch yarm and perm-its the latter to engage the contact |53 which is connected by conductor |54 to the red warning signal lamp |43 and to the audible signal |44 for which the energizing circuit is completed through conductors |41, 222, and lead wire |26.

Thus if satisfactory pressure is built up in the line during the iirst half of the operating cycle, the stem 232 will be protruded and will open the switch |40 so that as the `follower' 1| is engaged in the notch `35, the relay |45 will not be energized and the green light |5| will continue to burn. However, if the supply of lubricant is exhausted or for some other reason the proper pressure is not developed in the line 203 during the iirst half of the cycle, the stem 232 will not be protrude-d so as to open the switch |40, and as a, consequence the relay coil |45 will be energized by closing of the switch 1|] and the red warning light will be lighted and the audible signal will be sounded. The latching relay must be reset manually to shut off the warning signals and to restore the `circuit for the green light, thus insuring that the operator will take occasion to learn the reason .for failure of the apparatus to develop the proper pressure.

It will be understood that the applications of the timing mechanism to a dual line sytem, as shown in Fig. 8, and to a single line system, as shown in Fig. 9, are only illustrative and that this timing mechanism may be readily adapted to the control of various other systems, both in the lubrication field .and elsewhere. It will also be recognized that while there is shown and described herein certain structure embodying the .invention and illustrative thereof, the invention vis :not limited to .thespecic forms shown but embraces all changes and modiiications in its various features and `all equivalents thereof coming within the scope of the appended claims.

I claim:

1. In a lubrication system which includes a series of `measuring valves `each adapted to deliver lubricant in response to pressure applied to the Valve, conduit means connecting said valves, a supply of lubricant, conduit means connecting `said valves to said supply, and a pump operable to feed lubricant under pressure from said .supply to said valves, a timing mechanism comprising a clock, a frequency cam and `aduration cam driven -by the clock, switches actuated by said `cams respectively, electrically controlled driving means for said pump, control valve means between the outlet of the pump and the inlet to the system governing the application of pressure from the lpump to the measuring `valves and bypassing of lubricant from the valves, solenoid means operatively connected to actuate said control valve means, a source of electrical energy and a circuit which `includes said electrically controlled pump driving means, said solenoid means and said switches, said switches 'being actuated by said cams at predetermined intervals and for predetermined periods to energize said pumping means and to operate said valve means for supplying lubricant to the measuring valves.

2. In `a lubrication system 4which includes a se- Lries of measuring valves each having two ports from which lubricant is delivered alternately in `response to flow through the valve, first in one The lamp |5| is connected by conductors i direction and then in the opposite direction, conduit means connecting said valves :in a closed circuit, a supply of lubricant included in said circuit, and a pump operable to feed lubricant through said circuit in either direction, a timing mechanism comprising a clock, a frequency cam and a duration cam driven by the clock, a frequency switch and a duration switch actuated by said cams, respectively, and connected together in series, a source of electrical energy and electrically controlled driving means for said pump connected in a circuit with said switches and said energy source, said switches being closed at predetermined intervals and for predetermined periods to energize said pumping means, together with reversible valve means to control the direction of iow of lubricant through said series of measuring valves, solenoid means operatively connected to actuate said valve means, and a `third switch `controlling said solenoid means, said duration cam 4being formed to actuate said third switch substantially at the middle of each period of operation of the pump for operating said Valve means to reverse the flow of lubricant through the measuring valves.

3. In a lubrication system which includes a series Vof measuring valves, conduit means connecting said valves in a `closed circuit, each valve being adapted to deliver lubricant in response to pressure applied to the valve, rst in one direction and then in the opposite direction, a supply of lubricant included in said circuit, and a pump operable to feed lubricant through said circuit underl pressure in either direction, a timing mechanism comprising a clock, a frequency `cam and a duration cam driven by the clock, a frequency switch and a `duration switch actuated by said cams, respectively, and connected together in series, a source of electrical energy and electrically controlled driving means for said pump connected -in a circuit with said switches and said energy source, said frequency cam operating one of said switches at predetermined intervals to determine `the frequency at which said circuit is conditioned for operating said pump and said `duration cam operating the other of said switches to control the duration of a lubricating cycle togetherwith reversible valve means to control the direction of flow of lubricant through said series of measuring valves, solenoid means operatively connected `to actuate said valve means, land a third switch controlling said solenoid means, said duration cam being formed to actuate said third switch substantially at the middle of each period of operation of the pump for operating said valve means to reverse the direction in which pressure .is applied to the measuring valves.

4. In a lubrication system which includes a plurality of measuring valves each adapted to deliver lubrioant in response to the application of pressure, conduit means connecting said valves in sequence, a supply of lubricant, and a pump connected to feed lubricant from said supply to said measuring valves, bypass forming means for said system, a timing mechanism comprising a clock, a frequency cam and a duration -cam ,driven by said clock, a frequency switch and a duration switch actuated by said cams, respectively, and connected in series, electrically controlled driving means for said pump, a control valve between the outlet of the pump and the inlet to the system adjustable to a first position for applying the pump pressure to the measuring valves and to a second position for connecting said pump and the system to said bypass means, solenoid 11 means for shifting said valve, a source of electrical energy and a circuit which includes said electrically controlled pump driving means, said solenoid means and said switches, said duration cam serving to start the pump and energize the solenoid means for shifting the valve to said rst l position at the vbeginning of a period of operation and to shut off the pump and energize the solenoid means for shifting the valve to its said second position at the end of said period.

5. In a lubrication system as dened in claim 2 an electrically energized warning signal, a circuit by which it is connected with said source of electrical energy, a normally closed switch in said cucuit, and a normally open switch in said circuit, a pressure responsive device connected to a lubricant conduit leading from the pump to said measuring valves and operable in response to a predetermined pressure to open said normally closed switch, said normally open switch being the said third switch which is closed substantially at the middle of the period of operation of the pump and thus energizes the signal unless the pump has developed the predetermined pressure suiiicient to open the normally closed switch.

6. In a lubrication system which includes a series of measuring valves each adapted to deliver lubricant in response to pressure applied to the valve, conduit means connecting said valves, a

supply of lubricant, conduit means connecting o said valves to said supply and an electrically controlled pump operable to f eed lubricant under pressure from said supply to said valves, solenoid operated control valve means governing the application of pressure from the pump to the measuring valves and bypassing of lubricant from the valves, a timing mechanism, a frequency switch and a duration switch operated by said timing mechanism to 'energize said valve means and pump, a source of electrical energy and a circuit which includes said pump, valve means and timing mechanism, and a third switch in said circuit initially energizing said solenoid operated control valve means `to operate the same in one direction, i

said switch being operated by said timing mechanism at an intermediate point in each cycle of operation of the pump tc energize said solenoid operated valve means for moving the control valve to another position.

'7. In a lubrication system which includes a series of measuring valves each adapted to deliver lubricant in response to pressure applied to the valve, conduit means connecting said valves, a supply of lubricant, conduit means connecting said valves to said supply and a pump operable to feed lubricant under pressure from said supply to said valves, control valve means governing the application of pressure from the pump to the measuring valves, timing mechanism for actuat ing said pump and said control valve means at predetermined intervals and for predetermined periods for supplying lubricant to the measuring valves, electrically energized warning signals including a signal for indicating the presence of a predetermined pressure in the system, and a signal ,operable at a pressure below said predetermined pressure, a circuit for said signals including a normally closed switch controlling energization of said iirst signal, and a normally open switch controlling energization of said second signal, electrically energized means for simultane ously reversing the position of said switches, a circuit for energizing said means including a switch actuated to closed position by said timing mechanism at a predetermined interval aftei1 said pump is energized, and pressure responsive means for opening said circuit in advance of the closing of said last mentioned switch whena predetermined pressure is developed in the system.

8. In a lubrication system which includes a series of measuring valves each adapted to deliver lubricant in response to pressure applied to the valve, conduit means connecting said valves, a supply of lubricant, conduit means connecting said valves to said supply, and a pump operable to feed lubricant under pressure from said supply to said valves, a timing mechanism comprising a clock, a frequency cam and a duration cam driven by the clock, switches actuated by said cams respectively, electrically controlled driving means for said pump, control valve means governing the application of pressure from the pump to the measuring valves and bypassing of lubricant from the valves, solenoid means operatively connected to actuate said control valve means, a source of electrical energy, a circuit which includes said electrically controlled pump driving means, said solenoid means and said switches, said switches being actuated by said cams at predetermined in- Ytervals and for predetermined periods to energize said pumping means and to operate said valve means for supplying lubricant to the measuring valves, an electrically energized warning signal, a circuit'to connect said signal with said source of electrical energy, a normally closed and a normally open switch in said circuit, a, pressure responsive device connected to a lubricant conduit leading from the pump to said measuring valves and. operable in response to a predetermined pressure to open said normally closed switch, and means rendered effective by said duration cam to close said normally open switch during the period of operation of the pump for energizing the signal should the pump fail to develop a pressure at least equal to said predetermined pressure.

9. In a lubrication system which includes a series of measuring valves each adapted to deliver lubricant in response to pressure applied to the valve, conduit means connecting said valves in sequence, a supply of lubricant, a pump operable to feed lubricant under pressure from said supply to said Valves, control valve means governing the application of pressure from the pump to the measuring valves, timing mechanism to control operation of said pump and control valve means, a plurality of switches operated by said timing mechanism to cause said pump and said control valve means to be actuated at predetermined intervals and for predetermined periods for supplying lubricant to the measuring valves, an electrically controlled warning signal, a circuit to control energization of said signal, one of said switches operated by said timing mechanism being rendered effective thereby to connect said signal circuit to said source of current at a predetermined interval after operation of the pump is commenced, and a pressure responsive switch to open said circuit in response to a predetermined increase in pressure in the system.

REUBEN WEDEBERG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2.206.335 Retter July 2, 1940 2339,532 Venable Jan. 18, 1944 2,421,411. Clayton June 3, 1947