US2933859A

US2933859A - Apparatus for polishing and buffing sink ribs

Info

Publication number: US2933859A
Application number: US777399A
Authority: US
Inventors: Eldon J Guinn
Original assignee: Lyon Inc
Current assignee: Lyon Inc
Priority date: 1958-12-01
Filing date: 1958-12-01
Publication date: 1960-04-26
Anticipated expiration: 1977-04-26

Description

April 26, 1960 E. J. GUINN 2,933,859

APPARATUS FOR POLISHING AND BUFFING SINK RIBS Filed Dec. 1, 1958 4 Sheets-Sheet l April 26, 1960 E. .1. GU|NN 2,933,859

APPARATUS FOR POLISHING AND BUFFING sINK ms Filed Dec. l, 1958 4 Sheets-Sheet 2 I Erm-cm f/aon I Gw'nn EL@ @mf gw" WWEE April 26, 1960 E. J. GulNN 2,933,859

APPARATusNFoR PoLIsHING AND Bur-FING sINK RIBs Filed Dec. 1, 1958 4 Sheets-Sheet 3 Ergjrg- 67 haz-faz? Eldon J Gu/'nn April 26, 1960 E'. J, GUlNN 2,933,859

APPARATUS FOR POLISHING AND BUFFING SINK RIBS Filed nec.` 1, 195s 4 sheets-zshaet 4 z L z3/2.a a W Eran-far E/aon J.' Gwnn rotating iinishing element.

. finishing element.

APPARATUS FR POLISHING AND BUFFHNG SINK REBS Eldon J. Guinu, Detroit, Mich., assigner to Lyon lt1- corporated, Detroit', Mich.,` incorporation of Delaware Application December 1, 19558, Serial No. 777,399 '21 Claims. @LS1-92) This invention relates generally to huiiing machines and more specifically to an improved bufting machine which is particularly well adapted to polish the dividing rib of a divided sink. Y

Although the principles of the present invention may be included in various buing machines, a particularly 2,933,859; Patented'Apr. 26, 1960 A stillV further object of the present invention is to provide a control system for a nishing machine.

Many other advantages, features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailedl description and the accompanying sheets of drawings in which a preferred structural embodimentl incorporating the principles of the'present invention is shown by way of' illustrative example.

On the drawings:

Figure 1 is a front perspective view of a nishing machine provided in accordance with the VprinciplesV of the presentV invention, and shown partly broken away;

useful application is made in buing or polishing machines of the type that are employed to polish a combined upwardly and laterally directed surface, such as the dividing rib of a divided bowl stainless steel-.sinkt In particular, when stainless steel-sinks are manufactured, certain tooling marks are produced on the sink, the presence of which on a completed product is unsightly. In order to remove these marks, it is necessary to iirst polish, and then to buff the surfaces having such marks. The'instantinvention may be provided with either a polishing head or a buiiing head, andfor't'nis reason, these terms, insofar as they apply to the instant invention, are interchangeable, it being contemplated that either operation may be performed by this machine.

When either buffing or polishing is to be accomplished, it is desired to obtain a result wherein the polish marks remaining on the product are extremely iinerand uniformly aligned with the direction in which other polishing marks disposed on other parts of the sink extend. Thus where a rectangular sink has polishing marks along a back or front ledge which extend inthe principal direction of the sink, the marks which result on a rib transverse to the principal dimension of the sink must be transverse to the rib and thereby parallel with the marks left on the front and back ledges. Thus to polish the dividing rib of a divided sink, it is -necessary that the relative movement between the bufling or polishing element and the dividing rib ofthe sink be in the same direction as that in which the front and back ledges extend.

sink is supported. The table, in turn, is reciproeably driven up to and against a first rotating finishing element,

and then up to and against an oppositely directed second While the table is reciprocable in a horizontal direction, the iinishing elements preferably are vertically retractible and extendible so that they do not engage the end ledges of the sink. Controls are provided for the automatic control, co-ordination or synchronization of the table for this type of movement, as well as for the finishing elements.

Accordingly, it is an object of the present invention to provide an improved polishing and bufling machine.

Another object of the present invention is to provide a polishing and buing machine which is particularly well adapted to polish the dividing rib of a divided-bowl sink. t

Yet another object of the present invention is to provide a finishing machine wherein the workpiece is movably and automatically positionedl with respect to the Figure V2 is an enlarged perspective view of a portion of Figure 1 with a guard removed and with the finishing element elevated;

Figure 3 is generally similar to Figure 2 exceptl that the finishing element has been lowered;

Figure 4 is a perspective schematic diagram of the drive mechanism employed in the base of Figure 1;

FigureS is a schematic showing of a sink being engaged by a finishing element;

Figure 6V is a fragmentary elevational view, partly broken away, of an enlarged portion of the front of Figure 1;

Figure 7 is a schematic diagram of the electrical control system of the machine shown in Figure l; and

Figure 8 is a schematic diagram of the pneumatic system of the embodiment of Figure l.

As shown on the drawings The principles of this invention are particularly useful when embodied in a finishing machine such as illustrated in Figure l, generally indicated by the numeral 10. lThe finishing machine `10 generally includes a base or base assembly il having a workpiece supporting table i2 supported thereon and provided with means for driving the table 12 along the base 1i, generally indicated by the numeral i3, together with means responsive to table movement for controlling the driving means 13, best illustrated in Figure 7. The finishing machine i@ also includes a pair of supports 14a and 14b on each of which there is rotatably mounted a finishing element 15a and 15b, each of which is vertically positionable with respect to the base 11. The means responsive to table movement for controlling the driving means 13 also includes means for controlling thevertical position of theiinishing element 15. l

As best seen in Figure 1, the base l1 includes principally a pair of beams 16 which are laterally spaced from each other and which extend in a horizontal direction along thelength of the base 1l. To support the beams Viti, there is provided a series of vertically extending legs 18'rigidly secured to each of the beams i6,

and a series of horizontally extending braces 19, extending .transversely of the beams i6. lf desired, a serles Y of cover plates 2i may be provided to enclose the base 11, being secured to such members as the beams 16, the Vlegs 18, or the braces 19.

Each of the beams 16 is provided with an upwardly directed surface on which there is disposed an elongated track 24 of V-shaped section wherein the vertex extends upwardly.

As best seen in Figures 1 and 4, the base 11 is provided with a head. shaft 26 extending transversely of the tracks 24 and supported by a pair of

journals

27, 27*

for rotation. At a longitudinally spaced position from the shaft 26, the base 11 is also provided with a tail shaft29 rotatably carried by a vpair of adjustably positioned

journals

30, 30 for longitudinalmovement at the opposite or tail end of the base 11. The shaft 29 provided with a sprocket wheel 32 disposed intermediate 3 the

journals

30 and 30, while nthe shaft 26 is provided with two sprocket wheels, one wheel 33 being disposed intermediate the

journals

27, 27, and the other sprocket wheel 34 being disposed on one end ofthe shaft 26 outwardly of the journal 27. l

An endless member 35, here comprising a chain, extends about the

sprocket wheels

32 and 33 and is tensioned by the position of the tail shaft 29. 1f desired, a pair of guide or idler pulleys or sprocket wheels 36, 37 may also be included to direct the member 35 as required. The member 35 is secured to the table assembly 12, such as by a clamp 38'so that a portion of the member 35 is movable with the table 12.

In addition to the rotatably supported endless member 35, the means 13 for driving the table 12 along the base I1 also includesa reversible motor 39 adjustably secured to the base 11, by means not shown, together with a power train for connecting the motor 39 to the sprocket wheel 34. A crank wheel 17 shown in Figure ll extends through one of the cover panels 21 for adjustably positioning the motor 39. The power train includes a variable pitch pulley 40 secured to the output shaft of the motor 39, which pulley is coupled by a belt 41v to a pulley 42 which serves as an input to a speed reducer mechanism 43. The speed reducer 43 has an output sprocket wheel 44 coupled by a sprocket chain 45 to the sprocket wheel 34. A suitable guard (not shown) may -be employed to enclose the pulleys 40 and 42, and the belt 41.

By positioning the motor 39 selectively, using the hand crank 17, so that the pulley 40 has a given effective size, the table assembly 12 will be driven by the means 13 in a given direction at a substantially constant rate. As the direction of the motor rotation is reversed, the direction of rotation of the

shafts

26 and 29 is also reversed, thereby effecting table movement in the opposite direction. Thus the table assembly 12 may be driven toward and along each of the finishing elements 15a and 15b while being supported by the base 11, and may also be driven toward the opposite finishing element.

As best seen in Figures 1 and 6, the table assembly 12 includes a chassis 47 to which is secured a set of four rollers 48. Each of the rollers 48 has an outwardly or axially diverging V-shaped section which receives the V-shaped section of the tracks 24. This configuration prevents movement of the table transversely to the tracks 24. To the chassis 47 there is secured a frame or ycradle- 49 for supporting the workpiece, here shown to comprise a double-bowl sink 20 having a dividing rib 22. The cradle 49 functions to support the workpiece 20 so that it moves with the table 12 along the base 11,' and not transversely thereto.

Asshown in Figure 6, the table assembly 12 is also provided with at least one actuator element 58 rigidly secured to the chassis 47 for engagement with one or more of a series of switches 61-65. Since the actuating element 58 moves with the table 12, it isapparent that the engagement thereof with the various switches 61-65 is of an intermittent nature, and therefore the switches 61-65 are of a momentary type in a typical embodiment.

Each of the support assemblies 14a and 14b includes a foot 66 which supports a movable double slide 67 which in turn supports a column 68. The column 68 may be moved toward and away from the base 11 by moving the column 68 with respect to the slide 67, and the column 63 may be moved parallel to the end of the base' 11 by moving the slide 67 with respect to the foot 66.

As best seen in Figure 2, the column 68 supports a head assembly 69 which is vertically positionable thereon by means of a crank 70, and is angularly relatively adjustable with respect to the column 68 by means of another crank 71. The head 69 is manually positioned when the machine is set up for a given type of workpiece, the adjustments affecting head position thereafter not being adjusted. The head 69 supports a shaft 72V which is horizontally disposed and which extends par allel to the table path. The head 69 also supports a motor 73 which is coupled, as by pulleys and belts 74 to a driven member 75 which is rotatable about the axis of the shaft 72. The shaft 72 rockably or pivotably supports a yoke shaped arm 76 for angular movement about the axis of the shaft 72. The finishing element 15, in turn, is rotatably supported by an end of the arm 76 remote from the shaft 72. To this end, the finishing element 15 is provided with a shaft 77 which is rotatably carried by the varm 76, and which is provided with a pulley 78 which is driven through a series of belts 79 by the driven member 75.

The position of the motor 73 with respect to the rest of the head assembly 69 is adjustable so that the belt and pulley arrangement 74 is maintained taut. Similarly, the effective length of the yoke arm 76 between the

shafts

72 and 77 is also adjustable so that the belts 79 may also be kept taut.

The head assembly 69 also supports and includes a uid actuator 80 which has a rod 81 which is engageable with arroller 82 carried by the distal end of an extension S3 of the arm 76. Upon extension of the rod 81 as shown in Figure 2, the finishing element 15 is held in the elevated position as shown. Upon retraction of the rod 81, as shown in Figure 3, the arm 76 pivots about the shaft 72 so that the shaft 77 moves along an arc in a substantially vertical direction transverse to the path in which the table 12 moves, thereby moving the finishing element 15 toward the path of the table 12.

The arm 76 carrying the finishing element 15 is naturally unbalanced so that the finishing element 15 is actually lowered by the force of gravity in this embodiment. It has a total available movement such that the periphery of the finishing element 15 may move to a position lower than the upper surface of the rib 22 of the sink 20. Thus, when a workpiece is supported on the table 12, the finishing element 15 may engage it with a certain force. It can be seen that the actuator 8G and the arm '76 comprise a part of means for vertically positioning the finishing element 15 with respect to the table 12. Preferably, a guard 85, shown in Figure l, secured to the arm 76 and extending about the finishing element 15 is also provided.

To position the actuator 80, and hence the finishing element 15, an air supply 86 is connected to a solenoid actuated spring biased four-way valve 87 which communicates with the actuator 80. As best seen in Fig ure 8, the actuator 80 is a double-acting actuator which optionally is provided with a spring 88 which serves to raise the finishing element 15 in the event that fluid pressure is lost. The four-way valve 87 is also springbiased so that if electric power to the valve 87 be lost, the spool thereof will be so moved that fiuid pressure will act to raise the finishing element 15.

The valve 87, and hence the finishing elements 15a and 15b, and the motor 39, and hence the table 12, are operated by a control circuit which includes the switches 61-65. Therefore, the table driving means and the nishing elements vertical positioning means are under the control of means responsive to table movement.

The switches 61-65 are carried by a rail 89 which is secured to the base 11.' Each of the switches may be moved along the rail 89 and clamped in any desired position along the path of table movement.

The control circuit also includes additional switches 50-5'7, 59-60 carried by a control panel 95 best seen in Figure 1. The control circuit by which the embodiment shown in Figure l is regulated is shown in Figure 7. The switch 55 is a master switch of the normally closed push button type, the opening of which, even momentarily, shuts down the entire machine. Preferably, this switch includes a reset button 56.

In this embodiment, three-phase power is brought through a circuit breaker 23 to the

motors

73, 73, and

Vphase of each of the

motors

73, 73 and 39.

39. Power is also brought through a transformer 25, through appropriate fuses, to the master switch 55' and a main supply line Slt and a return line 46 between..

which are connected various control circuits.

Each of the motors '73 for rotating the finishing elements 15 is provided with Ian identical circuit to control the same. Control power passes from the master stop switch S through a normally closed Vpush button stop switch 5G and 53 respectively. Thence power passes through the normally open push button start switches 60 and 5i respectively. Closing of either of the switches 60 and 51 completes a circuit to the coil 96a and 96h respectively of a relay, which thereby closes to bring power to each of the motors 73.V For convenience, the various contacts of each relay have been identified with the same numerals as is provided for the coil of such relay. A pair of thermal overload switches 9'7, 97 is included in each of the coil circuits. Closing of each of the relays 95 also closes a holding circuit including a contact 9er: which bypasses the switch et) and a contact lb which bypasses the switch 5d whereby current is maintained through the coils 96 when the momentary push button switches 6l? and 61 are released, respectively. Thus lthe opening of either of the stop switches Sti and 53 interrupts the relay coil current to tie-energize th corresponding motor 73. Likewise opening the master switch 55 also interrupts the coil current.

Thermal overload switches 84 are provided for each it is to be understood that appropriate thermally responsive means, known in the art, are employed with each of the thermal overload switches 97 and 84 to actuate the same in response to excessive motor temperatures.

A relay 99 has contacts which connect the motor 3h to the line for driving the table 12 to the right as shown in Figure l. A relay 1@ has contacts for connecting the motor 39 to the line for driving the motor 39 in the opposite direction, and thereby driving the table to the left as shown in Figure l. The

relays

99 and 100 are mechanically inter-connected as indicated by the broken line to preclude simultaneous closing of the contacts of both relays, and are electrically inter-connected to prevent energizing of' one relay when the other is closed. To this end, the coil of the relay El? is connected through a pair of norm-ally closed contacts of `the relay 16d while the coil or" the relay tltl is connected thro-ugh a pair of normally closed contacts of the lrelayt. The relays 99 and lili? are commercially available Vas a unitary component employing the mechanical linkage lock and kare known as reversing starters.

`and tie-energizing the coil of the rel-ay 99. This controlv circuit includes in series a pair of cycle starting switches 52, 52, a normally closed element of the momentary switch 63, the above mentioned normally closed oontacts of the relay liti), the coil of the relay 99, and the overload switches 97, all connected across the lines 31 and fin. it will also be noted that thisV control circuit may include one or two pairs of normally closed relay contacts provided `:for interlocking purposes explained later herein. However, during the use of the control circuit fo'r the relay coil 99 just described, these contacts are not opened. holding circuit provided which extends across the

switches

52, 52 and which includes the momentarylimit switch 61 which is normally closed, and a pair of normally open contacts of the relay 99. When the motor 39 is being operated by this control circuit, opening of the limit switch 61 breaks the holding circuit, thereby causing the motor 39 to stop. This effects a table lmovement stoppage also. In order to prevent any unwanted coasting, the motor 39 may be provided with a brake 2- arranged to release the motor whenever it isenergized, and to prevent its rotation whenever it is tie-energized.

By referring to Figure l, it will be noted that the limit switch 61 is the middle one of the tive switches 61-65 so that if the cycle start switches 52 are actuated when the table 12 is at the switch 61 or to the right of it, table movement will take place to the right and the switch 61 will not be engaged by vsuch movement. Accordingly, movement'under this condition to the right will continue until the table12 actuates the normally closed element vof the limit switch 63 which defines the right-hand extreme selected limit of travel'of the table 12. Since the holding current for the relay 99 is interrupted by the opening of the normally closed element of the momentary switch 63, further movement to the right is automatically stopped. Y

A second control circuit for cyclic operation of the motor 39 is also connected across the

lines

31 and 45 and includes a pair of normally open contacts of 'a first ree versing relay 191, a normally closed element of the mo'- mentary limit switch 65, the normally closed contacts of the motor relay 99, the coil of the motor relay 10i), and the thermal overload switches 97. It can be seen that when the contacts of the relay 101 of this circuit are held closed, the motor 39 will drive in the opposite direction until the normally closed element in `the limit switch 65 is opened to thereby de-energize the motor 39. lf desired, this circuit may also include a pair of normally closed contacts of one or two interlocking relays similar to those mentioned for the first cyclic control circuit, the purpose of which is to be explained below. A

To close and to hold closed the contacts of the first reversing relay 101 which are in the second control cir-v cuit, there is provided a first reversing circuit which is energized by an auxiliary supply line 90 under the con- It will also be noted that there isa trol of the limit switch 6l. r[hus the `first reversing cir` cuit includes in series a normallyopen element of the limit switch 63, a pair of normally open contacts of a relay 103 forming a part of the control circuit for raising and lower ing the finishing element 15b, and the coil of the relay 101, as shown. A holding circuit is also provided which by-passes the normally open element of the limit switch 63 and the normally open contacts of the head relay 163, and includes normally open contacts of the first reversing relay 101. Thus when table travel toward the right, as

shown in Figure 1, is terminated by the opening of theY normally closed element of the limit switch 63, there is a simultaneous closing of the normally open element of the switch 63 which allowscurrent to pass to the reversing relay 101 provided that the finishing element 15b is in a lowered position, indicated by the fact that the normally open contacts of the right head relay 1l3 forming a part of the first reversing circuit are closed. This momentary closing of the reversing relay 1M also closes its holding` versing circuit has no eect whatever on the relay 160,

and while the subsequent momentary operation of the limit switch 61 breaks the current ow through the holding circuit of the first reversing circuit, the operation of the motor 39 does not stop because ofthe additional holding circuit provided by the contacts of the relay lili) which span the contacts ofthe rst reversing relay in the second control circuit. Thus, as stated above, the second control circuit continues to keep the relay energized until the normally closed element of the limit switch 65 is opened to terminate table movement to the left.

To return the table 12 from the left extreme to the center, there is provided a second reversing circuit including the coil` of a second reversing relay N2 which may be energizedwhenever the left finishing element 15a is in a ldownward position, accomplished by the closing of aseo ond. head relay 104. The second reversing circuit, like the first reversing circuit, is connected between the auxiliary supply line 90 and the return line 46 and includes in series a normally open element of the momentary switch 65, and a pair of normally open contacts of the head relay 104. The second reversing relay 102 is also provided with normally open contacts which are connected across the normally open element of the momentary switch 65 and the normally open contacts of the head relay 104, which relay contacts 102 thereby serve as a holding circuit for the second reversing circuit, such holding circuit being under the dominance of the limit switch 61. The second reversing relay 102 also includes an additional pair of normally open contacts which are thus held closed whenever the relay is energized. These additional contacts are connected across the holding circuit contacts of the motor relay 99 and thereby form part of a second holding circuit or path including the limit switch 61 for closing and holding the rst motor control circuit and -the relay 99 closed to return the motor toward a center position. It is apparent that de-energizing of the head relay 104 will have no effect on this operation, and that the opening of the limit switch 61 will break the holding circuit for the motor relay 99 as well as for the second reversing relay 102.

A pair of additional control circuitsr are provided, connected across the lines 31 and 46, for lowering and raising the finishing elements b and 15a respectively. The circuit for controlling the vertical position of the finishing element 15b includes the valve 87 having a solenoid coil 87b connected by means of normally open contacts of the relay 103 and suitable fuses 91 to the transformer 25. The actuator control circuit for the solenoid 87h includes in series a pair of normally closed contacts of the relay 100, a normally open element of the momentary switch 62, and a pair of normally open contacts of the relay 99, as well as the coil of the relay 103, all connected across the lines 31 and 46. It is apparent that this actuator control circuit may be closed when the table moves to the right from center and closes momentarily the normally open element of the switch 62, provided of course that the motor relay 99 is energized and that the motor relay 100 is not energized. This momentary energizing of the head relay 103 closes a pair of normally open contacts thereof which are connected across the normally open element of the switch 62 and the normally open contacts of the relay 99 as a holding circuit. Thus as the table continues to move to the right, the relay 103 remains energized, and after the table movement has been reversed, the holding circuit has not been broken. At the reversal of the motor 39 as described above, the normally closed contacts of the relay 100 open. Accordingly, there is provided a normally closed element in the momentary switch 62 which is connected across these normally closed contacts of the relay 100. Thus upon motor reversal, the normally closed portion of the switch 62 by-passes the now-open contacts, whereby the holding circuit for the head relay 103 is not interrupted. However, as the table 12 moves to the left and engages the momentary switch 62, the normally closed element thereof is momentarily opened to break the holding circuit.

It will be noted that a similar structure has been provided for the finishing element 15a which includes a solenoid 87a which may be energized by closing of normally open contacts in the relay 104 which are also energized via the fuses 91. A second actuator circuit for energizing the coil of the second head relay 104 includes in series, in addition to such coil, a pair of normally closed contacts of the relay 99, a pair of normally open contacts of the relay 100, and a normally open element in the momentary switch 64. Provided that the motor relay 99 is not energized, and provided that the relay 100 is energized (which occurs when the table moves to the left), the table 12 momentarily engages the momentary switch 64 to momentarily close the normally open element to complete the second actuator control circuit between the lines 31 and 46. This completion effects closing of the relay 104 which also closes a pair of normally open contacts thereof connected across the normally open element of the momentary switch 64 and the now-closed contacts of the relay 100, to serve as a holding circuit. Similarly, a reversal of the table at its left extreme of travel as shown does not break the holding circuit but does open the normally closed contacts of the motor relay 99. In order to prevent an interruption of current through the holding circuit at this point, a normally closed element of the momentary switch 64 is connected across such normally closed contacts. However, when the table reaches the momentary switch 64 as it moves toward the center of the `base 11, the normally closed element of the switch 64 is momentarily opened to break the holding circuit of the head relay 104, whereby the solenoid S7 becomes cle-energized and the finishing element 15a is caused to be moved in an upward direction.

Each of the actuator control circuits which include the

relays

103 and 104 may also include a pair of normally closed contacts of an additional relay, the purpose of which is explained below.

it is apparent that the co-ordinating and synchronizing portion of the circuit shown in Figure 7 described up to this point in this specification enables automatic cycling or sequencing of the various functions described. Thus `a manual closing of lthe start switches 52 causes the table to move to the right as shown, causes the finishing element 15b to be lowered during such movement for engagement with the rib 22 of the sink 20, effects a reversal of the table so that a second finishing pass is applied -to the workpiece, effects a raising of the finishing element 15b and subsequently thereto a lowering of the finishing element 15a which makes a pass on the opposite side of the rib 22, effects a table reversal which provides a second pass by the finishing element 15a, then causes the finishing element 15a to be raised, and after which the table 12 is stopped at a central position intermediate the finishing elements 15a and 15b.

Naturally, the hand selector wheel 17 is set so that the' motor 39 drives the table at the fastest practicable speed. However, this speed, even though it be relatively slow, is ordinarily too fast for set-up purposes. To that end, an additional manually controllable set of control circuits is provided so that the cycle above reviewed may be carried out in selected increments. It also permits the cycle to be substantially varied and reversed at will. Thus, in Figure 7, there is shown an additional set of control circuits which are manually Selectable and operable, and which in the instant embodiment have been'provided in combination with the automatic cycling circuits.

When both types of circuits are included in a single embodiment, it is necessary that an appropriate means be provided to prevent unwanted interaction between the two types of circuits. To this end, a selector switch 57 has been provided as shown nearthe bottom of Figure 7. The selector switch is connected to the main supply line 31, and may be selectably positioned neutrally or to supply power to the coil of a left selector relay 105, or to the coil of a right selector relay 106, each of which coils is connected to the return line 46. The right selector relay 106 has a pair of normally closed contacts in the first motor control circuit located at a point where the original closing current as well as the holding current must pass therethrough. The selector relay 106 also has a pair of normally closed contacts disposed in the second motor control circuit located at a point where initial closing current and any holding current must pass therethrough. The first actuator circuit for the right hand relay 103 also includes a pair of normally closed contacts of the selector relay 106 loassenso 9 i cated at a point where both'initial closing and holding current must pass therethrough. So long. as the selector switch 57 is not providing power to energize the selector relay 106, it can thus be seen that each one of the above enumerated auto-matic cycling circuits may be employed. However, the moment that thev selector switch 57 is positioned to energize the coil of the selector relay 106,-it can now be seen that the relay 106 will break all of such circuits, thereby preventing their being energized, or de-energlzing them as the case may be.

In like manner, the selector relay 105 is provided with normally closed contacts disposed in the iirst motor circuit for the relay 99, in the second motor control circuit for the relay 100, at points wherein the holding circuits for the

relays

99 and 100 also pass therethrough, and for Vthe closing and holding circuits for the leftactuator or head relay 104. Thus if the selector switch 57 is positioned to energize the relay 105, all such circuits are precluded from being energized, or become de-energiz'ed.

The selector relays 105 and 106 each also have appropriate normally open contacts which, upon closing, connect analogous manually operated moto-r control circuits and actuator head relay circuits to the supply line 31.

Thus there is provided a irst manually operable control circuit under the control of the selector relay 106 for energizing the coil of the relay 09 which includes in series therewith a pair of normally closed contacts of the rst reversing relay 101, the normally vclosed element ot' the momentary switch 63, apair of normally closed contacts of the relay 100, and a normally open'element of a manually operated momentary switch 54. Thus, closing of the manual switch 51tcauses the motor 39 to advance the table to the right as shown, but since there is no holding circuit, release of the switch 54 effects a stoppage of the table. This movement may continue until the switch 63 is engaged by the tableto break the normally closed element thereof.

In like manner, the device includes a second manually operable control circuit for the relay 100 and is connected in series with the coil thereof. This second circuit, under the control of the left selector relay 105 includes in series a pair of normally closed contacts f the second reversing `relay 102, the normally closed element of the momentary` switch 65, and the normally closed contacts of the motorrelay 99, as well as a second normally open element of the manually operable momentary switch S4. Closing of the switch 54 thus effects table movement to the left when the selector switch 57 is positioned to energize the selector relay 105. Release of the switch 54 again stops operation of the vmo-tor 39 j since there is no holding circuit. This movement may be continued until the switch 65 is engaged by the table to open the normally closed element thereof.

The first reversing circuit for the reversing relay 101 also includes a pair of normally open relay contacts from the relay 106 which are connected across the normally open contacts of the head relay 103. 1t will be noted that the reversing circuit is not otherwise under the inlluence'" of the selector relays. Accordingly, when the selector switch is positioned to energize the selector relay 106, the first reversing circuit is placed in an electrical condition wherein it may perform its reversing function without regard to the position of the heads, as is important during set-up. Thus when the table is manually moved to the right to actuate the limit switch 63, not only is tab-le movement to the right terminated, but the first reversing relay 101 becomes energized.V Closingof the lirst reversing relay 101 also closes an additional pair of contacts thereof which are connected across the relay contacts of the relay S and the relay contacts of the relay 102 in the second manually operable control circuit. The switch Sd being in a depressed position at this moment, an alternate .path is closed for energizing the motor relay Y100. Thus even though the `selector."v

switch 57 is energizing the relay 106, the table will move to the left. However, when the table reaches the central limit switch 61, the holding circuit for the lirst reversing relay 101 is opened whereby further movement of the table to the left cannot occur.

Just as the first reversing relay 101 is operative to effect reversal of table movement toward the finishing element 15b when the selector switch 57 is set to the selector relay 106, so is also the second reversing relay 102'operative to effect a reversal of the table when it is moving toward the finishing element 15a when the selector switch 57 is set to energize the selector relay 105. To this end,.the selector relay is provided with a pair of normally open contacts which by-pass the normally open contacts of the head relay 104 in the second reversing circuit which includes the coil of the reversing relay 102. Thus when the selector switch 57 is set to energize the selector relay 105 and the manually operable switch 54 is depressed, termination of the leftward table movement as shown not only elects the opening of the normally open element of the limit switch 65, but also effects a closing of the second reversing circuit including the reversing relay 102, and its holding circuit. When the second reversing circuit is thus operated, it is likewise not under any other influence of the selector relays 105 and 106. Thus, since the second reversing circuit is also powered by the auxiliary supply line`90, movement of the table to the right from the linishing element 15a is terminated when the table 12 engages the limit vswitch 61. Of course, it is to be noted that the second reversing relay 102 VValso includes an additional pair of normally open contacts connected to by-pass the normally open contacts of the selector relay 106 and the normally closed contacts of the first reversing relay 101 whereby current is brought from the supply line 31 by an alternate route to the remainder of the first manually operable control circuit for the motor relay 99. As is now apparent, a single switch push button of the switch 54 is thus operative to drive the table in either direction, dependingupon initially the position of the selector switch 57, and secondarily on whether the corresponding reversing relay has been actuated.

The selector relay 106 includes a further set of normally open vcontacts forming a part of a manually operable actuator circuit for the finishing elements 15b. This circuit includes in series the normally open contacts of the relay 106, the coil of the head relay 103, and a normally open portion ofa manually operable switch 59. Whenever the switch 59 is closed, provided the selector switch 57 is energizing the selector relay 106, the linishing element 15b is caused to move in a downward direction.

There being no holding circuit for the lirst head relay 103 under this condition, opening of the manually operable switch 59 'effects a raising of the lfinishing element 15b.

In like manner, the second head relay 10ft for the finishing element 15a is also provided with a manually opervrable actuator circuit including a pair of normally open contacts of the selector relay 105. and a second normally open portion of the manually operable switch 59. Thus when the switch 59 is closed, provided the relay 10S is energized, power is directed to the coil of the second head relay 4104 which velfects lowering of the head 15a. Likewise, an opening of the switch 59 effects a raising of the inishing element 15a. Thus it will be noted that depending upon the position of the selector switch 57, either one or neither one of the heads will be lowered by actuation of the manually operable switch 59.

While the preferred embodiment includes all of the featuresshown in Figure 7, it is to be understood that advantageous embodiments may 4be constructed wherein only various selected portions thereof are utilized.

Although various minor modifications might be suggested by those versed `in, the art, it should be understood that I wish to embody within the scope of the patent warranted hereon all such embodiments as reasonably and properly come within the scope of my contribution to the art.

I claim as my invention:

l. In a finishing machine, the improvement comprising in combinaiton: a base; a workpiece supporting table movably carried by said base; means for driving said table along said hase, said means including a reversible motor; a first relay adapted when closed to drive said motor in a table advancing direction; a second relay adapted when closed to drive said motor in an opposite direction; a third and a fourth relay connected to supply relay closing power to said first and said second relays respectively; and a manual selector switch connected to control which of said third and said fourth relays can be operated.

2. in a finishing machine, the improvement comprising in combination: a base; a workpiece supporting table movably carried by said base; means for driving said table along said base, said means including a reversible motor; a first relay adapted when closed to drive said motor in a table advancing direction; a second relay adapted when closed to drive said motor in an opposite direction; a third relay; a first control circuit having a normally open manually operated momentary switch for closing said first relay; a first holding circuit bypassing said manual switch and operative to keep said first relay closed; a first limit switch having a normally closed element in said first holding circuit and operative in response to advance of said table to open said first relay, and having a normally open element simultaneously operative to close a circuit to said third relay; a second control circuit responsive to closing of said third relayy for closing said second relay; a second holding circuit bypassing said normally open element of said first limit switch and operative to keep said third relay closed; and a second limit switch responsive to returning table movement and operative to open said second holding circuit to thereby open said third relay. I

3. In a finishing machine having a finishing element, the improvement comprising in combination: a workpiece supporting table movably supported adjacent to thev nshing element; means for driving said table past the finishing element, said means including a reversible motor; means for vertically positioning the finishing element with respect to the path of said table; a first relay adapt'- ed when closed to drive saidV motor in a table advancing direction; a second relay adapted when closed to drive` said motor in a table returning direction; a third relay for controlling said vertical positioning means; a first control circuit having a normally open manually operated momentary switch for closing said first relay; a first holding circuit connected across said manual switch and operative to keep said first relay closed; a`first limit switch having a normally closed element in said first holding circuit and responsive to advancement of said table and operative to open said first relay; a second con' trol circuit responsive to operation of a normally open element in said first limit switch for closing said second relay; a second holding circuit connected across said normally open element of said first limit switch and operative to keep said second relay closed; a third control circuit having a normally open momentary switch responsive to table advancement and operative to position said third relay to be operative on said vertical positioning means to effect movement of the finishing element toward the path of said table; a third holding circuit connected across said normally open momentary switch of said third control circuit and operative to keep said third relay closed; a normally closed momentary switch in said third holding circuit responsive to returning table movement and operative to position said third relay to be operative on said vertical positioning means to effect movement of the finishing element away from the path of said table; and

a second limit switch comprising a part of saidsecond holding circuit and responsive to further table movement and operative to open said second holding circuit.

4. In a finishing machine, the improvement comprising in combination: a base; a workpiece supporting table movably carried by said base; means for driving said table along said base, said means including a reversible motor; a first relay adapted when closed to drive said motor and hence said table in a first direction; a second relay adapted when closed to drive said motor and hence said table in an opposite direction; a third relay; a main electrical supply line and a return line; a first control circuit, including in series a normally open manually operated momentary switch, a normally closed element of a first limit switch responsive to movement of said table, and the coil of said first relay, connected across said lines; a first holding circuit bypassing said manual switch and operative to keep said first relay closed; a second control circuit, including in series a pair of normally open contacts of said third relay and the coil of said second relay, connected across said lines; a third control circuit, including in series a normally open element of said first limit switch and the coil of said third relay, connected to said return line; a second holding circuit bypassing said normally open element and operative to keep said third relay closed; and a second normally closed limit switch responsive to table movement connecting said supply line to said first holding circuit, said third control circuit, and said second holding circuit.

5 In a finishing machine, the improvement comprising in combination: a base; a workpiece supporting table movably carried by said base; means for driving said table along said base, said means including a reversible motor; a first motor relay adapted when closed to drive said motor and hence said table in a first direction; a second motor relay adapted when closed to drive said motor and hence said table in an opposite direction; a first reversing relay; a second reversing relay; a main electrical supply line and a return line; a first control circuit, including a normally open manually operated momentary switch, a normally closed element of a first momentary limit switch responsive to table movement, and the coil of said first motor relay, connected in series across said lines; a

first holding circuit bypassing said manual switch and operative to keep said first motor relay closed; a second control circuit, including a pair of normally open contacts of said third relay, a normally closed element of a second momentary limit switch responsive to table movement, and the coil of said second motor relay, connected' in series across said lines; a first reversing circuit, including in series a normally open element of said first limit switch and the coil of said first reversing relay, connected to said return line; a second holding circuit bypassing said normally open element of said first limit switch and op erative to keep said first reversing relay closed; a second reversing circuit, including in series a normally open element of said second limit switch and the coil of said second reversing relay, connected to said return line; a third holding circuit bypassing said normally open element of said second limit switch and operative to keep said second reversing relay closed; a fourth holding circuit including contacts of said second reversing relay connected across said first holding circuit; and a third normally closed limit switch responsive to table movement connecting said supply line to each of said four holding circuits and said two reversing circuits.

' 6. In a finishing machine, the improvement comprising in combination: a base; a workpiece supporting table movably carried by said base; means for driving said tabie along said base, said means including a reversible motor; a first motor relay adapted when closed to drive said motor and hence said table in a first direction; a second motor relay adapted when closed to drive said motor and hence said table in an opposite direction; a first reversing relay; a second reversing relay; a main electrical supply line and a return line; a first controll asse-,85a

. 13 circuit, including a rst normally open element of a manually operable momentary switch, a pair of normally closed contacts of said first reversing relay, the coil of said rst motor relay, and a normally closed element of a first momentary -lirnit switch responsive to table movement, connected in series across said lines; a second control circuit, including a second normally open element of said manually operable momentary switch, a pair of normally closed contacts of said second reversing relay, the coil of said second motor relay, and a normally closed element of a second momentary limit switch responsive to table movement, connected in series across said lines; a lirst reversing circuit, including in series a normally open element of said first limit switch and the coil of said first reversing relay, connected to said return line; a first holding circuit bypassing said normally open element of said first limit switch and operative t'o keep said first reversing relay closed; a second reversing circuit, including in series a normally open element of said second limit switch and the coil of said second reversing relay, connected to said return line; a second holding circuit bypassing said normally open element of said second limit switch and operative to keep said second reversing relay closed; said first reversing relay having a pair of normally open contacts connected across said normally closed contacts of said second control circuit; said second reversing relay having a pair of normally 'open contacts connected across said normally closed contactsrrof said first control circuit; and a third normally closed limit switch responsive to table movement connecting said .supply line to Aeach of said holding and reversing circuits.

7. In a finishing machine, the improvement comprising i-n combination: a base; a workpiece supporting table movably carried by said base; means for driving said table along said base, said means including a reversibley motor;

a first motor relay adapted when closed to drive said motor and hence said table in a first direction; a second motor relay adapted when closed to drive said motor and hence said table in an opposite direction; a first reversing relay; a second reversingy relay; a main electrical supply line and a return line; a first manually energizable control circuit, responsive to movement of said table, connected across said lines `for operating said first control relay and said first reversing relay; a second control circuit energizable by said first reversing relay, responsive to movement of said table in the opposite direction, and connected across said lines for operating said second control relay and said second reversing relay; said first control circuit being energizable also by said second reversing relay; and a limit switch responsive to table movement and operative on at least one o-f said control circuits to stop movement of said table at a generally central position along said base.

8. In a finishing machine, the improvement compris.- ing in combination: a base; a workpiece supporting table movably carried by said base; means for driving said table along said base, said means including a reversible motor; a first motor relay adapted when closed to drive Vsaid motor and yhence said table in a first direction; a

second motor relay adapted when closed to drive said motor and hence said table in an opposite direction; a

rst reversing relay; a second reversing relay; a main.

electrical supply line and a return line; aY first manually energizable control circuit under the control of said reversing relays, including a first limit switch responsive to movement of said table, said circuit being connected across said lines for operating said first control relay and one of said reversing relays; a second control circuit -manually energizable under the control of said reversing relays, including a second Vlimit switch responsive to opposite movement of said table, said circuit being connected across said lines for operating said second control relay and the other of said reversing relays; whereby when said first control circuit is manually energized, said limit switch, andl when said second control circuit Vis,

manually energized, said table is driven toward said second limit switch, and upon engaging said second limit;

switch is driven toward said first limit switch.

9. ln a finishing machine, the improvement comprising in combination: a base; a workpiece supporting table movably carried by said base; means for driving said table along said base, said means including a reversible motor; a first motor relay adapted when closed to drive said motor and hence said table in Ya first direction; a second motor relay adapted when closed to drive said motor and hence said table in an opposite direction; a first reversing relay; a `second reversing relay; a main electrical supply line and a return line; a pair of first manually energizable control circuits having a common portion, including a first limit switch in said portion responsive to movement of said` table, said circuits being connected across said lines for operating said first controlrrelay and one of said reversing relays; a pair of second control circuits having a common portion, including a second limit switch in said portion responsive to opposite movement of said table, said circuits being connected across said lines for operating said second control relay and the other of said reversing relays, one of said second control circuits being manually energizable under the control o said reversing relays, and the other of said second control circuits being energizable by said one reversing relay; a selector circuit operative to select one of said first circuits and said one of said'second control circuits for manually controlled table movement, and the other of said first circuits and said other of said second control circuits for automatically controlled table movement; and a third limit switch dis-v posed intermediate said first and second limit switches and comprising a part of said other first circuit for terminating said automatically controlled table movement.

l0. In av finishing machine, the improvement comprising in combination: a base; a workpiece supporting table movably carried by said base; means for driving said table along said base, said means including a reversible motor; a rst motor relay adapted when closed to drive said motor and hence said table in a first direction; a second motor relay adapted when closed to drive said motor and hence said table in an opposite direction; a. reversing relay;` a main electrical supply line and a return line; a first control circuit, including `a first normally open element of a manually operable momentary switch, a pair of normally closed contacts of said reversing relay, the coil 'of said first motor relay, and a normally vclosed element of a first momentary limit switch responsive to table movement, connected in series across 'said lines; a Y

second control circuit, including a second normally open element of said manually operable momentary switch, a pair of normally open contacts of said reversing relay, the coil of said second motor relay, and a normally closed element of a second momentary limit switch responsive to table movement, connected in series across said lines; a reversing circuit, including in series a noi'- nially open element of said first limit switch and ther coil of said reversng relay, connected to said return line; a holding circuit bypassing said normally open element of said first limit switch andjoperative to keep said reversing relay closed; and a third normally closed limit switch responsive to table movement connecting said supply line to said reversing and holding circuits.` v

ll. ln a finishing machine, the improvement comprising in combination: a base; a workpiece supporting table movablv carried by said base; means for driving said table along `said base, said means including a reversible motor; a 4first motor control circuit operative to drive 4said motor and said tabie in one direction; a second motor control circuit operative to drive said mtor and said table in theopposite direction; a limitsswitch in said first circuit actuated by said table and connected to means operative to transfer motor control from said first circuit to said second circuit; and a limit switch in said second circuit actuated by said table and connected to means operative to transfer motor control back to said first circuit; and a second limit switch in said first circuit actuated by said table and operative to terminate table movement.

12. In a finishing machine, the improvement comprising in combination: a base; a workpiece supporting table movably carried by said base; means for driving said table along said base, said means including a reversible motor; a first motor control circuit, having a first normally open element of a manually actuated switch, and operative to drive said motor and said table in one direction; a second motor control circuit, having a second normally open element of said manually operated switch, and operative to drive said motor and said table in the opposite direction; and a limit switch in each of said'circuits actuated by movement of said table and connected to means operative to transfer motor control to the other of said circuits.

13. In la finishing machine, the improvement comprising in combination: a base; a workpiece supporting table movably carried by said base; means for driving said table along said base, said means including a reversible motor; a pair of first motor control circuits, having a common limit switch actuated by movement of said table and operative to drive said motor and said table in one direction; a second pair of motor control circuits, having a common limit switch actuated by movement of'said table and operative to drive said motor and said table in the opposite direction; a selector switch operative to select one of said first and one of said second circuits, each being adapted for manual operation, or the other of said control circuits, being each adapted for :automatic operation; and said limit switches being connected to means operative to transfer motor control from either of said selected circuits to the other of said selected circuits for each position of said selector switch.

14. In a finishing machine having a finishing element, the improvement comprising in combination: a base, a workpiece supporting table movably carried by said base adjacentto the finishing element; means for driving said table with respect to the finishing element in a path along said base, said means including a reversible motor; means including a self returning actuator for verticallypositioning the finishing element with respect to said path of said table; a first motor control circuit operative to drive said motor and said table in one direction; a second motor control circuit operative to drive said motor and said table in the opposite direction; and an actuator control cricuit operative to position the finishing element; said circiuts being interconnected so that said actuator control circuit can effect positioning of the finishing element toward the workpiece only when said' motor is driving in said one direction, and away from the workpiece only when said motor is driving in said opposite direction.

15. In a finishing machine having a finishing element, the improvement comprising in combination: a base, a workpiece supporting table movably carried by said base `adjacent to the finishing element; means for driving said table with respect to the finishing element in a path along said base, said means including a reversible motor; means including a self returning actuator for vertically positioning the finishing element with respect to said path of said table; a first motor relay adapted when closed to drive said motor and hence said table in a first direction; asecond motor relay adapted when closed to drive said motor and hence said table in an opposite direction; an actuator relay adapted when closed toV position the finishing element toward the workpiece; a main electrical supply line and a return line; a first control circuit, responsive to movement of said table, connected across said lines for operating said rst control relay; a second control circuit, responsive to movement of said table, connected across said lines for operating said second control relay; an actuator control circuit, responsive to movement of said-table, connected across said lines for operating said actuator relay, said actuator circuit including a pair of normally open contacts of said first control relay so that said actuator relay can be energized only when said motor is driving in said one direction; and a holding circuit bypassing said normally open contacts and responsive to table movement in said opposite direction so that said actuator relay can be de-energized only when said motor is driving in said opposite direction.

16. In a finishing machine having a finishing element, the improvement comprising in combination: a base, a workpiece supporting table movably carried by said base adjacent to the finishing element; means for driving said table with respect to the finishing element in a path along said base, said means including a reversible motor; means including a self returning actuator for vertically positioning the finishing element with respect to said path of said table; a first motor relay adapted when closed to drive said motor and hence said table in a first direction; a second motor relay adapted when closed to drive said motor and hence said table in an opposite direction; an actuator relay adapted when closed to position the finishing element toward the workpiece; a main electrical supply line and a return line; a first control circuit, responsive to movement of said table, connected across said lines for operating said first control relay; a second control circuit, responsive to movement of said table, connected across said lines for operating said second control relay; an actuator control circuit, including in series a normally open element of a momentary switch responsive to table movement, a pair of normally open contacts of said first control relay, and the coil of said actuator relay, connected across said lines so that said actuator relay can be energized only when said motor is driving in said one direction; and a holding circuit, including in series a normally closed element of said momentary switch and a pair of' normally open contacts of said actuator relay connected in series with said coil but bypassing the remainder of said actuator control circuit, and a pair of normally closed contacts of said second control relay bypassing said normally closed element, so that said actuator relay can be de-energized only when said motor is driving in said opposite direction.

17. In a finishing machine having a pair of spaced finishing elements, the improvement comprising in combination: a base; a workpiece supporting table movably carried by said base intermediate and adjacent to the finishing elements; means for driving said table with respect to the finishing elements in a path along said base,y

said means including a reversible motor; a pair of means each including a self returning actuator for one of thel finishing elements, each means being operative to posi-l tion said one of the finishing elements with respect to said path of said table; a first motor control circuit operative' to drive said motor and said table in one direction; a second motor control circuit operative to drive said motor.v and said table in the opposite direction; an actuator con-y trol circuit for each of said actuators, each actuator con` trol circuit being operative to position the corresponding finishing element; each of said actuator circuits being interconnected with both of Vsaid motor control circuits so that one of said actuator control circuits can effect positioning of its finishing element toward the workpiece only when said motor is driving in said one direction, and awayfrom the workpiece only when said motor is driving in said opposite direction, and so that the other of said ac tuator control circuits can effect positioning of the other finishing element away from the workpiece only when said motor is driving in said one direction, and toward the workpiece only when said motor is driving in said opposite direction.

18. A nishing machine including in combination: ay

base; a reciprocable workpiece supporting table movably carried by said base along a path; a pair of finishing elements, one disposed at each end of said path adjacent to said path; means for reciprccably driving said table with respect to said finishing elements; means for individually reciprocating said finishing elements transversely to said path; and means responsive to table movement for coordinating operation of said table driving means and said element reciprocating means.

19. A finishing machine including in combination: a base; a reciprocable workpiece supporting table movably carried by said base along a path; a pair of pivotally supported arms, one disposed at each end of said path adjacent to said path; a finishing element secured to each of said arms; each of said arms having a fluid actuator operatively coupled thereto whereby said finishing elements may be moved individually toward and away from said table path; means for reciprocably driving said table with respect to said finishing elements; and means responsive to table movement for coordinating operation of said actuators with said table driving means.

20. In a finishing machine for the dividing rib of a divided sink, the improvement comprising in combination: a base; a reciprocable sink-supporting table movably carried by -said base along a path and adapted to support the sink with the dividing rib thereof disposed parallel to said path; a pair of finishing elements, one disposed at each end of said path adjacent to said path, each rotatable about an axis parallel to said path, one of said elements being laterally positionable for engagement with one side of the rib, and the other of said elements 18 being laterally positionable for engagement with the opposite side of the rib; and means for reciprocably driving said table for moving the sink rib along each of said nishing elements.

21. A finishing machine including in combination: a base; a reciprocable workpiece supporting table movably carried by said base along a path; a pair of finishing elements, one disposed at each end of said path adjacent to said path; means for reciprocably driving said table with respect to said finishing elements; means for individually reciprocating said finishing elements transversely to said path; a coordinating circuit including a group of five momentary switches carried by said base in spaced relation to each other along said path and each individually responsive to movement of said table; the endmost of said switches each being operative to effect reversal of said driving means, the middle one of said switches being operative to stop said driving means only when the table is moving in one of its two directions, and the other two switches each being respectively operative to effect reciprocation of one of said finishing elements toward said path when said table is moving toward the corresponding endmost switch, and to effect reciprocation of said one finishing element away from said path when said table is moving away from the corresponding endmost switch.

References Cited in the file of this patent UNITED STATES PATENTS