US3494434A - Elevator-type loader with metered discharge and automatic weighing - Google Patents

Description

Feb. 10, 19-70 I c. F. RIVERS 3,494,434

ELEVATOR-TYPE LOADER WITH METERED DISCHARGE 1 AND AUTOMATIC wmcnxue Filed June 12. 1967 H I 3 Sheets-Sheet l FIG-1 m a4 *5 V 48 9 a? v T3 in .3? 1 2 INVENTOR. J6\ J; (4mg: flfili'eb,

BY mp4! 26 L Madam ATTORNEYS Feb. 10, 1970 c. F. RIVERS ELEVATOR-TYPE LOADER WITH METERED DISCHARGE AND AUTOMATIC WEIGHING 3 Sheets-Sheet 2 Filed June 12, 1967 G 4 6 a i m U Q 1.. so as Ex 4 8 a r ll] lwaLilwnlu w o 2 .0 Z i J J 4 \I J M/ x a 4 f a 6 8 6 My 8 M w a 9 a M 1 INVENTOR.

67/452415 fen 66 E Y W W W A T TOR/V5 Y5 C. F. RIVERS -TYPE LOADER WITH METERED DISCHARGE Feb. 10, 197.0

. ELEVATOR um 12, 1967 AND AUTOMATIC WEIGHING s Sheets-Sheet s FIG.4 I

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me, MW M a United States Patent US. Cl. 177-53 7 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally to loaders and comprises an upright frame having an elevator or elevators for raising small parts and discharging them over the rear wall of the frame. The top edge of the rear wall is cut on a bias, or at an angle to the horiozntal, so that the individual parts will be discharged one by one as the elevator moves upward. This provides for a metered closely controlled discharge of the parts.

A hopper is provided for receiving the discharged parts. The hopper is supported on an adjustable scale balance. When the weight of parts in the hopper reaches a certain predetermined amount, a limit switch is operated to stop the discharge of parts from the loader. Means are also provided for dumping the contents of the hopper in response to the positioning of a tray in parts-receiving position with respect to the hopper.

SUMMARY OF THE INVENTION It is an essential object of this invention to provide an improved loader having means for providing a metered, closely controlled discharge of parts.

Another object is to provide a loader having a hopper for receiving the discharged parts, and having means for rendering the loader inoperative in response to a predetermined accumulation of parts in the hopper.

Another object is to provide a loader having an adjustable scale balance for the hopper operative to actuate a limit switch when a predetermined weight of parts has accumulated in the hopper.

Another object is to provide means for dumping the contents of the hopper in response to the presence of a tray or receiver in parts-receiving position with respect to the hopper.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in coiijunction with the accompanying drawings, wherein:

FIGURE 1 is a vertical sectional view of apparatus embodying my invention, taken on the line 1-1 of FIG- URE 2. I

FIGURE 2 is a sectional view taken on the line 22 of FIGURE 1.

FIGURE 3 is a sectional view taken on the line 33 of FIGURE 1.

FIGURE 4 is a view taken on the line 44 of FIG- URE 2.

FIGURE 5 is a sectional view taken on the line 55 of FIGURE 4.

FIGURE 6 is a fragmentary elevational view showing the upper edge of the rear wall of the loader.

FIGURE 7 is a wiring diagram.

Referring now more particularly to the drawings, the reference character 10 designates the loader which includes an upright frame 12 of generally rectangular crosssection. The frame 12 extends vertically although it will be understood that in some instances it may be desired to have the frame extend upwardly but at an angle to the vertical. The frame 12 includes the elongated vertical corner angle members 14 which define the rectangular outline of the frame. Parallel side walls 18 and 20 extend between the angle members to define the sides of the frame.

The loader includes front and rear elevators 22 and 24 which are vertically reciproca ble within the frame, and intermediate frame structure 25. Spaced vertical rails 26, 28 are rigidly secured to the side walls 18 and 20 and are provided to guide the vertical movement of front elevator 22. Elevator 22 is shown in FIGURE 1 in its lowermost position in solid lines and in its uppermost position in dotted lines. The elevator 22 includes a vertical front plate 30, a vertical rear plate 32 and elongated side channels 34. Parallel runners 36 are secured to channels 34 and travel on rails 26, 28 during the vertical reciprocation of the elevator. The vertical rear plate 32 of elevator '22 slides along the vertical front plate 40 of the intermediate frame structure 25. A rearwardly sloping lifting plate or platform 44 is provided at the top of the elevator 22. The vertical front plate 40 of the intermediate frame structure 25 provides a continuation of the rails 26 to support the elevator 22 during its upward movement.

The intermediate frame structure 25 has a rearwardly sloping shelf or platform 48 at its upper end which shelf slopes at the same angle as and is aligned with the lifting plate of platform 44 of elevator 22 in the upper position of the latter.

The lifting plate or platform 44 is rectangular and extends from side-to-side between the side walls 18 and 20 of the frame. In a front-to-rear direction, the lifting plate 44 extends between the rails 26, 28 in the lowermost position of the elevator and, upon being raised, extends between the rails 28 and the vertical front plate 40 of the intermediate frame structure 25. During upward movement of elevator 22, the parts on lifting plate 44 are confined on the sides by side walls 18 and 20 and at the rear by vertical wall 40.

Elevator 24 is shown in FIGURE 1 in its lowermost position in solid lines and in its uppermost position in dotted lines. The elevator 24 includes a vertical front plate 48, a vertical rear plate 50 and elongated side channels 52. Parallel runners 54 are secured to the channels 30 and travel on spaced vertical rails 56, 58 secured to side walls 18 and 20 during the vertical reciprocation of the elevator. The vertical front plate 48 of elevator 24 slides along the vertical rear plate 59 of the intermediate frame structure 25. A rearwardly sloping lifting plate or platform 60 is provided at the top of the elevator 24. The

vertical rear plate 59 of the intermediate frame structure 25 and vertical channels 57 secured to side walls 18 and 20 provide a continuation of rails 58 to support the elevator 24 during its upward movement. The rear wall 61 of the loader frame 12 provides a continuation of rails 56 to support elevator 24 during upward movement.

The sloping shelf or platform 48 slopes at the same angle as and is aligned with the lifting plate of platform 60 of elevator 24 in the lower position of the latter.

The lifting plate or platform 60 is rectangular and extends from side-to-side between the walls 18 and 20 of the frame 12. In a front-to-rear direction, the lifting plate 60 extends between the rails 56, 58 in the lowermost position of the elevator and, upon being raised, extends between the rear wall 59 of the intermediate frame structure 25 and the rear wall 61 of frame 12. During upward movement of elevator 24, the parts on lifting plate 60 are confined on the sides by side walls 18 and 20, and at the rear by rear wall 61.

The loader has a charging chute 64 for the delivery of individual small parts to the elevator 22 through the front of the loader. It will be noted that the chute 64 has a bottom wall 66 which is sloped at the same angle as and is flush with the lifting plate 44 of the elevator 22 in the lower position of the latter. The lifting plate 44 of the elevator 22 runs along the edge 67 of the bottom wall 66 of the chute.

It will also be noted that the frame includes a discharge chute 68 at the rear thereof, the bottom wall 70 of which is inclined at the same angle as the lifting plate 60 of elevator 24. The elevators 22 and 24 are reciprocated in unison with one another so that when elevated to their upper positions the elevator 22 will transfer parts on its lifting plate 44 to the metering shelf 48, while the elevator 24 will discharge parts on its lifting plate 60 over the upper edge of the rear wall 61. In the lower positions of the elevators, the lifting plate 44 of elevator 22 will receive parts from the chute 64 and parts on the metering shelf 48 will be transferred to the lifting plate 60 of elevator 24.

The means for reciprocating the elevators comprises a reversible electric motor 72 which drives a gear box 74 having an output sprocket 76. A chain 78 around sprocket 76 and around sprocket 80 on shaft 82 rotates shaft 82. Shaft 82 is supported in fixed hearings on the frame 12 and has spur gears 84 in mesh with racks 86 on elevator 22. A chain 88 extending around sprocket 90 on shaft 82 and sprocket 92 on shaft 94 transmits rotation to shaft 94. Shaft 94 is supported in fixed bearings on the frame 12 and has spur gears 96 in mesh with racks 98 on elevator 24. It is obvious that operation of motor 72 in one direction will simultaneously raise the elevators to their upper limits and rotation of the motor in the opposite direction will simultaneously lower the elevators to the lowermost positions shown in FIGURE 1.

The discharge chute 68 delivers parts into a hopper 100 positioned beneath the discharge chute. The hopper 100 is supported on a transverse member 101 secured to the rear ends of pivot bars 102 which form part of a scale balance 104. The bars 102 are parallel with one another and located on opposite sides of the frame, being mounted intermediate their ends on shaft 105 pivoted to the frame in pillow block bearings 106. Each of the pivot bars 102 comprises a pair of laterally spaced bar members or elements 108. Supported on each one of the pivot bars between the bar elements thereof is a counterweight box 110. The boxes 110 each have a channel member provided with horizontal flanges 111 engaging over bar elements 108 to slidably support the box 110 on the pivot bars. Threaded rods 112 which are rotatably supported in bearings at opposite ends of the pivot bars are threaded through the counterweight boxes 110 so that rotation of the threaded rods by handles 115 operates to adjust the position of the counterweight boxes along the pivot bars. There are pointers 116 fixed upon the counterweight boxes 110 and scales 117 along the pivot bars 102 so that the positions of the counterweight boxes may be readily determined by reference to the scale.

There is a normally open limit switch LS3 supported upon the frame 12 of the loader. There are abutments 117 and 118 positioned above and below the pivot bars to permit a certain amount of vertical movement of the pivot bars, and normally when the hopper is empty or underfilled, the pivot bars will rest on the lower abutment 118. However, upon filling the hopper to a predetermined amount depending on the positions of counterweight boxes the balance will swing from the posi tion in FIGURE 1 into engagement with ,the upper abutment 119, closing the limit switch LS3.

It will be noted that a receiver or tray 119 is supported on a conveyor 121 beneath the hopper 100, and when the receiver or tray is in such position it engages and closes normally open limit switch LS4. It will also be noted that as a part of the hopper 100, there is a door forming a bottom wall of the hopper, which door is hinged for pivotal movement by hinge pins 122. An air cylinder 123 is provided for opening and closing the hopper door, one end of the cylinderbeing pivoted to a fixed portion of the hopper and the piston rod of the cylinder being pivoted to the door. When limit switch LS4 is closed air under pressure is admitted to the piston end of cylinder 123 by valve SV through lines 126 and 128 to extend the piston rod and open the hopper door to discharge the contents of the hopper into the receiver or tray 119. Opening of switch LS4 causes the piston rod to retract as by the action of a return spring in the cylinder.

The upper edge 124 of the rear wall 61 of the frame 12 is cut on a bias from end-to-end along a straight line which is inclined with respect to the horizontal and extends for the full width of the lifting plate 60 of elevator 24. When the elevator is at its upper limit, the lifting plate 60 thereof is level with or slightly above the upper end of the edge 124 of the rear wall. Hence as the lifting plate moves upward past the upper edge 124, parts are discharged one by one beginning at the low end of the upper edge 124 and progressing toward the upper end thereof. This provides a slow, metered or controlled discharge of parts from the loader. FIG- URE 6 shows the elevator 24 before it reaches its upper limit.

In the automatic operation of the loader, the elevators 22 and 24 are reciprocated continuously until a certain predetermined weight of parts has accumulated in the hopper 100. This predetermined weight of parts is dependent upon the setting of the counterweight boxes 110 along the pivot bars 102. When the parts accumulate in the hopper to an extent causing the pivot bars 102 to swing counterclockwise in FIGURE 1 so as to engage abutment 117 and operate limit switch LS3, the elevators are immediately reversed without continuing to their upper limits, lowered to their FIGURE 1 positions and stopped.

In operation, the switch PB will be closed to start the loader. Referring to FIGURE 7, it will be noted that the limit switch LS1 has two contacts LS1a and LS1b, and the limit switch LS2 has two contacts LS2a and LS-Zb. The limit switch LS1 is located in position to be operated by the elevator 24 when in its lowermost position, and the limit switch LS2 is positioned to be operated by the elevator 24 when in its upper position. The limit switches are shown in FIGURE 7 in their normal positions when neither one is operated by the elevator or for example when the elevators are in an intermediate position. Assuming, that the elevators are in their lowermost positions, the limit switch LS1 will be operated so as to open contacts LS-la and close contacts LS-lb. Hence the closing of switch PB will serve to energize the time delay relay TD2. The time delay of relay TD2 may for example be three seconds so that at the end of a three-second period the relay contacts TD2-1 will close to energize the coil MP of the motor starter closing contacts MP in the motor circuit and energizing the motor for operation in a direction to raise the elevators. The coil MP has a contact MP1 in a holding circuit around contact TD2-1 so as to lock in the circuit to coil MF after the elevators move from their lowermost positions and cause contact LS-lb to open and deenergize relay TD2.

At the uppermost positions of the elevators, limit switch LS2 is operated to open contact LS-2a and thereby deenergize the coil MP to open the motor circuit and deenergize the motor. At the same time limit switch contact LS-2=b is closed to energize time delay relay TD1.At the end of the delay set into TDl, for example three seconds, the relay contacts TD11 close to energize the coil MR closing contacts MR in the motor circuit to operate the motor in the reverse direction lowering the elevators. The coil MR has a contact MR1 in a holding circuit to lock in the circuit to coil MR after the elevators descend far enough to release the limit switch LS2 causing the deenergization of time delay relay TDl through the open contact LS-2b. When the elevators reach their lowermost positions, limit switch LS1 is again operated opening limit switch contact LS- 1a to deenergize starter coil MR, thereby opening the circuit to the motor and stopping the motor. The cycle will thereafter repeat itself with the result that parts will be raised by the elevators to the metering shelf 48 and then to the discharge chute 68, to gradually fill the hopper 100.

The loader continues to cycle and deliver parts to the hopper 100 until a predetermined weight of parts has accumulated in the hopper causing the balance to swing and close limit switch LS3. This energizes relay CR1 which Opens the normally closed contact CR1-1 in the circuit to coil MF thereby immediately halting the rise of the elevators. It will be understood that the accumulation of parts to the predetermined weight in the hopper will occur during an upward stroke of the elevators and a metered discharge of parts over the upper edge 124 of the rear wall of the loader. When this predetermined weight of parts has been reached in the hopper, causing an over-balance of the hop-per and an operation of limit switch LS3, the effect will be to immediately stop the upward movement of the elevators and accordingly stop any further discharge of parts from the loader.

Also upon closing of limit switch LS3 there will occur the closing of relay contact CR1-2 which will close the circuit to the starter coil MR causing an immediate reversal and descent of the elevators. When the elevators reach their lower limit, the coil MF will not be re-energized to cause the elevators to cycle upward, due to the fact that relay contact CR11 is opened. Hence the loader will stop operating at this point with the elevators in the lowermost position.

If at this point, a receiver or tray 119 is located in position to receive parts from the hopper, the tray will close limit switch LS4 to energize solenoid valve SV, causing the valve to admit air under pressure to the cylinder 123 to open the hoper door 120 and discharge the parts in the hopper to the tray. The time delay relay TD3 is also energized and after an interval of tlme, for example three seconds, the relay contact 'ID3-1opens to break the circuit to the solenoid valve SV and thereupon permit the cylinder 123 to return to its normal position closing the hopper door.

Discharging the parts from the hopper causes the balance to again return to its normal FIGURE 1 position opening limit switch LS3 and thus deenerglzlng relay CR1 and permitting the normally closed relay contact CR1-1 to close. Accordingly, the circuit to the starter coil MF will be established to permit the elevators to rise from their lowermost positions and thereupon repeat the cycle of operation causing a refilling of the hopper 100. Refilling of the hopper will continue until limit switch LS3 is operated in response to the accumulation of a predetermined Weight of parts in the hopper. If in the meantime tray 119 has moved away from its partsreceiving position, limit switch LS4 will be opened and this will maintain the solenoid valve circuit SV open. Time delay relay TD3 will also be deenergized to close the normally closed contact TD31. Then when the tray 119 again moves into parts-receiving position with respect to the hopper, it closes the limit switch LS4 to effect a discharge of the parts from the hopper into the tray.

The bias on the upper edge 124 of the rear wall 61 of the loader makes it possible to have a gradual, metered discharge of parts, so that when the exact desired weight of parts has accumulated in the hopper 100, the loader elevators will reverse and the loading of parts into the hopper will immediately cease.

What I claim as my invention is:

1. Loading apparatus comprising a frame having a rear wall portion, said rear wall portion having an upper edge extending thereacross, a parts elevator, means for moving said elevator relative to said rear wall portion of said frame from a lower position to an upper position, said elevator having a parts-supporting lifting platform inclined downwardly and rearwardly and movable across said upper edge during movement of said elevator to its upper position to discharge parts over said upper edge of said rear wall portion, said upper edge throughout at least a portion of its extent across said rear wall portion being inclined to provide a metered discharge of parts as said elevator moves to its upper position.

2. The loading apparatus defined in claim 1, wherein said inclined portion of said upper edge extends for the full transverse extent of said lifting platform.

3. The loading apparatus defined in claim 2 wherein said upper edge is inclined from one end to the other on a straight line.

4. Loading apparatus comprising a frame having a rear wall, a parts elevator, means for moving said elevator relative to said frame from a lower position to an upper position to discharge parts over the upper edge of said rear wall, said elevator having a parts-supporting lifting platform movable across said upper edge during movement of said elevator to its upper position, said upper edge being elongated transversely of said frame, said upper edge extending for the full transverse extent of said lifting platform and being inclined from one end to the other on a straight line to provide a metered discharge of parts as said elevator moves to its upper position, said moving means being operative to reciprocate said elevator continuously between its lower and upper positions, a parts receiver positioned to receive the parts discharged over the upper edge of said rear wall, and control means responsive to a predetermined weight of parts in said receiver accumulated during an upward movement of said elevator to cause said moving means to immediately reverse said elevator and return said elevator to and stop the same in its lower position.

5. The loading apparatus defined in claim 4, wherein said receiver is carried by a pivoted balance, and said control means includes a limit switch operable by said balance.

6. The loading apparatus defined in claim 5, including a receptacle, and means responsive to movement of said receptacle into parts receiving position with respect to said receiver for discharging the parts in said receiver into said receptacle.

7. Loading apparatus comprising a frame having a rear wall, said rear wall having a discharge opening, a parts elevator, means for moving said elevator relative to said rear wall of said frame from a lower position to an upper position, said elevator having a parts-supporting lifting platform inclined downwardly and rearwardly and movable across said discharge opening during movement of said elevator to its upper position to discharge parts through said discharge opening, at least a portion of the lower edge of said discharge opening extending across said rear wall at an angle to the horizontal to provide a metered discharge of parts as said elevator moves to its upper position.

(References on following page) References Cited UNITED STATES PATENTS Sinden 198168 XR Sayers -v- 198168 Orton 214-2 Scott 21416.16 Curioni 1771 14 XR Jee et a1. 177114 Forman et a1. 17756 Nichols et al.

Mellow 214-2 Mueller 177114 XR Starnbera 17752 8 3,232,449 2/1966 Quinshen. 3,406,838 10/1968 Davidson.

FOREIGN PATENTS 952,365 3/1964 GreatBritain. 5 574,752 3/1958 Italy. 600,669 12/1959 Italy. 127,946 4/1960 Russia.

10 ROBERT S. WARD, 111., Primary Examiner U.S.C1.X.R.

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