Title:
Delayed-action control device
United States Patent 2467989


Abstract:
This invention relates to control devices, and particularly to such devices as secure a desired effect after the lapse of a given period of time following the actuation of the device. It is an object of this invention to provide an improved device of this character capable of sustaining hard...



Inventors:
Porch, Howard L.
Application Number:
US49853143A
Publication Date:
04/19/1949
Filing Date:
08/13/1943
Assignee:
FMC CORP
Primary Class:
Other Classes:
118/25, 118/324, 118/684, 118/699, 318/440
International Classes:
A23B7/16; B05B13/02
View Patent Images:
US Patent References:
2335424Windshield wiper parking device1943-11-30
2179536Electric system1939-11-14
1584748Circuit controller1926-05-18
1575010Limit switch1926-03-02
1440803Automatic time switch1923-01-02
0974480N/A1910-11-01



Description:

This invention relates to control devices, and particularly to such devices as secure a desired effect after the lapse of a given period of time following the actuation of the device.

It is an object of this invention to provide an improved device of this character capable of sustaining hard use over long periods of time without requiring attention thereto, and without failure.

Remote control is often effected by the turning on or off of a switch in an electric circuit.

Where a fluctuating value is depended upon for actuating this control and the switch is directly responsive thereto an excessive burden is placed upon the switch, as the life of such switches is relatively limited.

It is an object of this invention to provide a delayed-action control device functioning through an electric switch in which intermittent actuation by the controlling value short of a sustained actuation for a pre-determined length of time, is not transmitted to said switch.

This application is a division of my co-pending application for U. S. Letters Patent, Serial No. 403,079, filed July 19, 1941, for Coating spray control, now Patent No. 2,362,926. The present invention has wide utility, but for illustrative purposes it is disclosed herein as when employed in said coating spray control.

The manner of accomplishing the foregoing objects, as well as further objects and advantages, will be made manifest in the following description taken in connection with the accompanying drawings, in which: Fig. 1 is a diagrammatic cross sectional view of a fruit coating machine at present in current commercial use with a preferred form of the device of my invention embodied therewith, this view showing an orange just leaving said machine and another orange just entering said machine, the entering orange being positioned to start a spray of coating material in the machine.

Fig. 2 is a fragmentary view illustrating a portion of Fig. 1 in which the device of my invention is embodied with the parts thereof disposed as when no fruit is entering said machine.

Fig. 3 is a longitudinal sectional view of the control mechanism of my invention showing it positioned as when stopping the spray of coating material in said machine.

Fig. 4 is a horizontal sectional view taken on the line 4-4 of Fig. 3.

Fig. 5 is an enlarged fragmentary longitudinal sectional view taken on the line 5-5 of Fig. 4, this view showing the clutch of said control mechanism engaged as when no fruit is entering the machine.

Fig. 6 is a view similar to Fig. 5 showing the clutch of said control mechanism disengaged as by fruit entering the machine.

Fig. 7 is a vertical cross sectional view taken on the line 7-7 of Fig. 5 and showing the switch opened and motor and spray shut off.

Fig. 8 is a similar vertical cross sectional view taken on the line 8-8 of Fig. 6, showing the switch allowed to close, motor and spray turned on.

Fig. 9 is a wiring diagram of the electric circuit of the invention.

Referring specifically to the drawings, I have shown therein a spray waxer 10 including a rectangular housing I, having a floor 12, supporting legs 13, front and rear walls 14 and 15, side walls 16 and a top wall 17. Provided in the front and rear walls 14 and 15 are fruit inlet and discharge openings 20 and 21, there being a delivery board 22 mounted along the lower edge of the opening 20 and inclined inwardly for receiving fruit delivered to the machine 10, while a dis2p charge board 23, inclined outwardly, is provided in the discharge opening 21 of the machine.

Mounted in a manner well known in the art, in the interior of the housing II, is a roller conveyor 25, the upper flight 26 of which is disposed along an upwardly inclined path so that when this conveyor travels in the direction of the arrow 27 it receives fruit from the delivery board 122, conveys this along a path extending through the machine 10 and discharges this fruit onto the discharge drop board 23 over which the fruit gravitates from the machine. Provided in the end wall 14 is a motor housing 28 which contains a motor 29 for driving the conveyor 25.

Mounted on the top wall 17 is a power spray unit 30 having nozzles 31, this unit expelling from these nozzles streams 32 of.fine atomized particles of a solution of coating material so that these particles travel directly from the nozzles 31 into contact with fruit travelling on the conveyor upper flight 26 within the zone 33 (see Fig. 1).

One of the walls 16 is provided with an air exhaust opening 40 which connects with a suction space 41 disposed just below the upper conveyor flight 26, the bottom of which is covered by a 60 drip pan 42 and a semi-cylindrical wall 43 which connect together, as shown in Fig. 1, and extend entirely across the space between the side walls 16. A suitable air blower (not shown) is disposed outside the housing II and connected with the 655 opening 40 to evacuate air from the chamber to the suction space 41, thus drawing air downwardly between the rollers of the upper conveyor flight 26 while the machine is operated so as to prevent an accumulation of vapors of the solvent used in connection with the coating material applied by the machine 10.

The delivery board 22 has a depressible middle plate 50 provided with a finger 51, the latter resting against the upper end of a rod 52 which slides in a collar 53 mounted on the wall 14. The lower end of rod 52 is pivotally connected to an arm 55 of a clutch lever 56 of a control mechanism 57 which is mounted on the floor 12 in the motor housing 28. Attached to the rod 52 and the wall 14 is a spring 58 which holds this rod and the depressible plate 50 in upward position, as shown in Fig. 2, excepting when one or more pieces of fruit F may be rolling across this plate. When the latter occurs, as shown in Fig. 1, the weight of this fruit causes the plate 50 and rod 52 to be depressed with results to be described hereinafter.

The control mechanism 57 includes a rectangular shell 60 to the bottom of which is secured by bolts 61 a frame casting 62 having walls 63, 64, 65, 66 and 67 extending upwardly therefrom.

Extending through suitable holes in the walls 65 and 66 and pinned in place is a clutch yoke shaft 70 on which the bifurcated lower end of the clutch yoke 56 is pivotally mounted. As shown in Figs. 3 and 4, this clutch yoke has screws with heads 72 which are located in closely spaced relation with the body of the yoke 56.

Mounted on the wall 67 is a small motor 73 with a gear box 74, the latter gearing the motor 73 to a shaft 75, this latter being received axially in an opening in one end of a clutch shaft S7 and rigidly secured thereto by a set screw 77, said shaft having at its other end a portion 78 of reduced diameter which extends into and journals in a hole 79 in the wall 63. Freely rotatable on the shaft portion 78 is a cone clutch bell 88, this bell having pins 81 and 82 extending radially therefrom. Connected at its opposite end to the pin 81 and to the wall 65 is a contractile spring 83. Adjustably mounted in a slot 84 formed in the wall 63 is a stop pin 85, the purpose of this pin being to limit the angular position of rest of the clutch bell 80 when the spring 83 rotates this bell so as to bring the pin 81 into contact with the pin 85.

Secured on the wall 64 is a Micro-switch 88 having a yieldable arm 89, the depression of which brings this into engagement with a switch pin 90 which opens switch 88. As shown in Figs. 3, 4 and 7, the inner end of the switch arm 89 extends into the rotational path of the clutch pin 82.

Splined on the shaft 76 is a clutch cone 91 which unites with clutch bell 80 to form a clutch 92. The clutch cone 91 has an annular flange 93 which extends between the clutch yoke 56 and the bolt heads 72.

The electric circuit of the machine 10 is shown in Fig. 9 where it is seen that coating material solution is fed to the nozzles 31 through a pipe 95, this pipe having a valve 96 controlled by a solenoid 97. Electricity is supplied from power lines L-I and L-2 through conductors 98 and 99 to the timing motor 73 and the solenoid 97. The switch 88 is located between the main line L-1 and the conductor 98 so that when this switch is closed by the arm 89 being released from pressure from the pin 82, current is supplied to the timing motor 73 causing this to run, and to 76 the solenoid 97 causing this to open the valve 96 and permit coating material solution to be supplied through the pipe 95 to the nozzles 31, thus causing sprays of atomized particles of coating material solution 32 to be produced and directed against pieces of fruit F travelling on the upper conveyor flight 26 through the zone 33. Likewise, when the switch arm 89 is depressed, as when this is engaged by the clutch pin 82 so as to open the switch 88, this immediately shuts off the valve 96 and the timing motor 73.

Operation The problem involved is to so control the production of atomized particles of coating material solution 32 that all of the fruit F passing through the machine 10 will be properly covered with coating material, yet not permit an accumulation of this coating material on the rolls of the conveyor S25 during a break in the supply of fruit to the conveyor, so that when fruit is again supplied to this conveyor excess quantities of coating material are picked up by the fruit from the conveyor rolls, thus doing a bad job of coating the fruit and probably damaging the fruit.

In the normal operation of the machine iS the fruit F is fed in a more or less continuous supply across the drop board 22 and is carried in a continuous flow along the pathway lying just above the upper conveyor flight 26 and thence out of the machine over the drop board 23. Flowing along this path the fruit P passes through the coating zone 33 in which the fruit is subjected to the cones of atomized particles of coating soluStion 32 produced by the nozzles 31.

When changing from one lot of fruit to another and in certain minor emergencies in the packing of the fruit, which are not of infrequent occurrence, there is a cessation of the supplying of fruit F over the delivery board 22 to the conveyor 25. As soon as the fruit is being delivered in a relatively constant flow over the delivery board 22 pieces of fruit F are rolling over and depressing the plate 50, as shown in Fig. 1. This movement is transmitted to the arm 55 and swings the clutch yoke 56, as shown in Fig. 6, thereby compressing the spring 94 and withdrawing the clutch cone 91 from the clutch bell 80. The clutch bell si thereby freed to be rotated by the spring 83 about its shaft 78 into the position in which it is shown in Fig. 8 where the pin 8 1 has been brought to rest against the stop pin 85.

When the clutch bell 80 is so positioned, the pin 82 is out of contact with the spring switch arm 89 which causes the switch 88 to remain closed. As already pointed out, while this condition exists the motor 73 continues to rotate the shaft 75 and the clutch shaft 76 and the clutch cone 91 splined thereon, and the valve 96 continues to remain open causing the nozzles 31 to spray coating material onto the fruit.

Whenever there is any cessation of the supply of fruit F to the conveyor 25, so that the depressible plate 50 is allowed to rise under the influence of the spring 58, as shown in Fig. 2, the clutch yoke 56 is brought into vertical position under the influence of springs 58 and 94, thus frictionally inserting the clutch cone 91 into the clutch bell 80. As the shaft 76 is being continuously rotated by the motor 73 (although this rotation is at a very slow rate of speed owing to the low gear ratio in the gear box 74) the clutch cone 91 is also being rotated and this rotation is transmitted to the clutch bell 80 which if the plate 50 remains in Supper position, as shown in Fig. 2, for a predetermined interval, results in the pin 32 being shifted from the position in which it is shown in Fig. 8 to the position in which it is shown in Fig. 7 where it depresses the switch arm 89 and opens the switch 88.

As previously pointed out, opening this switch de-energizes the motor 73 and the solenoid 97 and shuts off the valve 96 thereby causing the delivery of atomized coating material to the zone .3 to cease immediately.

The rest position of the pin 8 I is so determined by the location of the adjustable stop pin 85 in the slot 84 that the predetermined interval of time intervening between the cessation of the supply of fruit to the conveyor 25 and the de-energizing of the timing motor 73 and the solenoid 97 is such that the last of the fruit supplied over the delivery board 22 to the conveyor 25 is carried by the upper flight of this conveyor a sufficient distance into the zone 33 during this interval so that this fruit has received an adequate deposit of coating material from the nozzles 31 before the latter are shut off by the de-energizing of the solenoid 97.

When the supply of fruit F to the upper flight of the conveyor 25 is resumed, the first piece of fruit to cross the delivery board 22 depresses the plate 50 of this delivery board thereby immediately turning on the supply of coating material solution to the nozzles 31 and causing a resumption of the application through these nozzles of atomized particles of coating material to any fruit travelling in the zone 33 on the upper conveyor flight 26. Thus the initial fruit supplied to the machine 0 on the resumption of operations, after a cessation of said supply, is assured of receiving an adequate deposit of coating material directly from the nozzles 31.

The intermittent character of the stream of fruit P crossing the delivery board 22 causes the plate 50 to be shifted between the positions in which it is shown in Fig. 1 and Fig. 2 a relatively large number of times. Each of these movements of the plate 50 is transmitted to the clutch 92 and either opens or closes this clutch. That is, each such movement of the plate 50 shifts the lever 58 from one to the other of the positions of this shown in Figs. 5 and 6.

In actual commercial practice these actuations of the plate 50 by the fruit F are as frequent as 150 per minute. In the mechanism of my invention each of these actuations merely operates the clutch 92. Only when a predetermined period has elapsed without the plate 50 being depressed, is the clutch 92 allowed to remain engaged long enough for the pin 81 to be rotated into engagement with the switch arm 89 so as to open the switch 88.

It is thus seen that the device of my invention effects control through an electric circuit by operation of a switch therein in response to an intermittently occurring value (that is, no fruit F on the plate 50) without this switch being required to function in response to the occurrence of said value until and unless that value continues to exist for a predetermined period of time.

I have accomplished this protection of the switch for the reason that no switches of this type are available which will stand operation as frequently as would be necessary if the device were designed so that the switch is closed or opened each time the plate 50 moves between the positions in which it is shown in Figs. 1 and 2. The clutch 92, however, which is responsive to each of these movements of the plate 50, is capable of enduring this rapid actuation over long operating periods without failure.

While I have shown and described a single embodiment of my invention, it is to be understood that various changes and modifications might be made in this without departing from the spirit of the invention and the scope of the appended claims.

I claim: 1. In combination: an electric motor; an electric circuit including said motor; a switch in said circuit; lost motion means adapted to shut off said switch upon said means being shifted a predetermined extent from a starting position; a clutch directly connecting said motor to said lost motion means for positively shifting the latter as aforesaid; means automatically returning said lost motion means to starting position when said clutch is released; and means inde0o pendent of said motor circuit for throwing said clutch in and out.

2. In combination: an electric motor; an electric circuit including said motor; a switch in said circuit; lost motion means adapted to shut off 2e said switch upon said means being shifted a predetermined extent from a starting position; a clutch directly connecting said motor to said lost motion means for positively shifting the latter as aforesaid; means automatically return3o ing said lost motion means to starting position when said clutch is released; means independent of said motor circuit for opening said clutch in response to a given control value; and means for automatically closing said clutch when said opening means is released.

3. In combination: an electric control circuit including a switch; lost motion means adapted to actuate said switch upon said means being shifted a predetermined extent from a starting position; power means; a clutch directly connecting said power means to said lost motion means for positively shifting the latter as aforesaid; means automatically returning said lost motion means to said starting position when said clutch is released; and means independent of said control circuit for throwing said clutch in and out.

4. In combination: an electric control circuit including a switch; lost motion means adapted to actuate said switch upon said means being shifted a predetermined extent from a starting position; power means; a clutch directly connecting said power means to said lost motion means for positively shifting the latter as aforesaid; means automatically returning said lost motion means to said starting position when said clutch is opened to disconnect said power means from said lost motion means; means independent of said control circuit for opening said clutch; and means for automatically closing said clutch when said opening means is released.

5. In combination: an electric switch which is normally closed; a clutch including a driven element and a driving element; an electric motor, the circuit of which includes said switch; means connecting said motor to said driving element to rotate the latter at a substantially uniform rate; means responsive to a given degree of rotation of said driven element to open said switch; means constantly acting on said driven element for returning said driven element and said switch opening means to their starting position whenever said clutch is opened; and means independent of said switch for controlling the closing and opening of said clutch.

6. In combination: an electric motor; an electric circuit including said motor; a normally closed switch in said circuit; lost motion means adapted to shut off said switch upon said means being shifted a predetermined extent from a starting position; a clutch directly connecting said motor to said lost motion means for positively shifting the latter as aforesaid; means automatically returning said lost motion means to starting position whenever said clutch is disengaged; and means independent of said motor and said motor circuit for engaging and disengaging said clutch.

7. In combination: an electric switch; a clutch including a driven element and a driving element, said driven element being adapted to actuate said switch when rotated by said driving element to a given position; means yieldably rotating said driven element a given distance away from said position to a starting position whenever said Number 974,480 1,440,803 1,575,010 1,584,748 2,179,536 2,335,424 Name Date Foster -------------Nov. 1, 1910 Uphoff ------------- Jan. 2, 1923 Schier -------------Mar. 2, 1926 Toomey ---------- May 18, 1926 Wolff ---------- Nov. 14, 1939 Korte et al. -------- Nov. 30, 1943 clutch is disengaged; means for rotating said driving element at a substantially uniform rate; and means for engaging and disengaging said clutch independently of said switch and said rotating means.

HOWARD L. PORCH.

REFERENCES CITED The following references are of record in the 10 file of this patent: UNITED STATES PATENTS