US1918990A - Electrical feed for planers - Google Patents

Description

July 18, 1933. J. c. SHAW EI'AL 1,913,990

ELECTRICAL-FEED FOR PLANERS Filed Juhe- 23. 19:1 2 Sheets-Sheet 1 July 18, 1933. J. c. SHA ET AL ELECTRICAL FEED FOR PLANERS 2 Sheets-Sheet 2 Filed June 23, 1931 NQQ Patented July 18, 1933 UNITED STATES PIA-TENT OFFICE JOHN C. SHAW AND ROBERT D. SHAW, OF BROOKLYN, NEW YORK, ASSIGNORS TO PRATT & WHITNEY COMPANY, OF HARTFORD, CONNECTICUT, A CORPORATION OF NEW JERSEY ELECTRICAL FEED FOR PLANE-RS Application filed June 23,

This improvement relates to a simplified electrical feed for ordinary planers and, since it eliminates traced control, may be considered an improvement upon our pending application Serial No. 206,824, for electric tracer control of the feed of planers or the like.

In the prior application, the toward and from feed andtransverse feed (right or left) are controlled .by the tracer or manuaily, through separate relays with an interlocking relay, and a rotary commutator detel-mines the length of time, during the noncutting stroke, that one or the other of the controlling relays may be energized to permit operation of one or the, other of the feeds.

A drum switch is'alsoprovided, in the form shown in'the prior application, for changing the circuit connections, so as to eliminate the tracer when it is desired to effect feeds for ordinary planing, but in that case the operation is still through the multiplicity of relays and switches and thewhole arrangement is more or less complex. .i The object, therefore, of the present 1mproi ement is to simplify the circuit connections and arrange to operate the ordinary automatic feeds of the planer electrically through a single relay, closing a single circuit, adapted to operate directly any of the magnetic clutches that may be properly included in the circuit to obtainthe desired feed, either transverse or toward and from.

A further object is to provide suitable manually operated controlling switches for either feed, for instance for placing in the single circuit to be closed by the single relay the clutches for automatic toward or from feed, a single contact switch is operated for toward or from feed and a double contact switch for the part cular clutch for the toward or from feed as desired. Similarly when it is desired to operate automatic transverse feed, suitable manual switches are provided for placing in the single relay circuit the clutches for transverse feed and of these the particular clutch for either; right or left transverse feed as desired.

It is desirable to effect the transverse feed between the tool and work during or at either end of the stroke of the reciprocating member 1931. Serial No. 546,228.

and to predetermine and limit the feed by some form of timing device. The timing device limits the duration of the feed by'limiting the operation of the inagnetic clutches for effecting the feed and a further object of the present improvement is to utilize the intermittently rotating commutator for operating a single relay closing a single operating circuit to the respective clutches, selected according to'the feed required, the commutator being provided with the usualcontact surface of variable width, and contact brush cooperating therewith, which ismovable to vary the length of time the commutator surface is in contact, for determining the length of time the feed clutch is in operation.

In our improved planer, it is necessary to provide means" (as a substitute for the usual crank) for adjusting the relation between'the tool and the work, independently of the automatic feed, that is, for operating the feed screws for adjusting the tool toward or from the work and locating it transversely in proper position, before starting the automatic feed operation of the planer. A further object, therefore, is to provide manual switches for closing circuits directly to the respective clutches so that any adjustments of this character, for properly locating the tool with reference to the work, can be made before the automatic feed is started, thus eliminating ord nary hand cranks which are usually provided for this pur ose. r

The preferred form of t e present im provement is shown in the accompanying drawings, in which Fig. 1 is a plan view of the feed regulating device; Fig. 2 is a side "iew, partially in vertical section on the line quired to explain the present improvement are shown schematically with suflicient clearness to illustrate the electrical feed control.

As usual in planers, the tool 104 is adapted to effect a linear cut on the work by reciprocating the work table 102, the tool being -mounted on the usual swinging support 105,

so that, since the cut is effected only during movement in one direction (indicated by the arrow on table 102), the tool will swing free upon the reverse or non-cutting stroke of the table and work. The swinging tool holder 105 is mounted upon a (vertically moving) slide or carriage 106 for toward and from feed, the slide 106 being mounted on the transverse carriage 107, which as usual is mounted on slide ways 108 for transverse motion or feed in the usual manner, or to properly locate the tool for the successive cuts.

The tool carriage 106 for toward and from feed between the tool and the work is adapted for feed motion by the usual lead screw 109, Which, in the present instance is connected to a clutch armature 110, cooperating with a pair of magnetic clutch members 111. The clutch members 111, designated N and S are adapted to be rotated in opposite directions by the attached bevel gears meshing with a pinion 112, which is adapted to be continuously driven by a suitable motor, the magnetic clutch unit being substantially as shown in Shaw Patent No. 1,683,581, of September From this arrangement, it will be seen that by energizing one or the other of the magnetic clutches 111, the tool 104 will be fed either toward or from the work, toward, if the S clutch is energized and from, if the N clutch is energized. In ordinary planing, the toward and from position of the tool is" usually adjusted before starting the trans- "verse feed, which is usually operated as a step by step feed, for the successive cuts, but obviously, the arrangement may be reversed and the step by step feed effected by the toward and from feed clutches 111.

Similarly, the transverse slide 107, carrying the tool carriage 106 and the feed screw 109 therefor and also the toward and from feed operating magnetic clutches 111, mounted thereon, is adapted to be fed transversely of the machine in the usual manner by a lead screw 113, which is keyed or operatively connected to a clutch armature 114 cooperating with a pair of magnetic clutches 115, designated l3 and W, for right or left feed motion. The magnetic clutch members 115 are also adapted to be rotated in opposite directions by a continuously rotating motor driven bevel pinion 116, operating in bevel gears secured to the respective clutch members 115,

.the arrangement being substantially as previously described for the clutches 111. Thus it will be understood that by energizing one the main 'switch 121 and from the switch through a circuit 7 to the armature 122 of a relay 123, the armature being normally held in open positionby a spring 124, as will be seen in Fig. 3.

The relay armature 122 is adapted to close the circuit on contact 9 of the return circuit and suitable manually operated switches are provided for determining the type of feed and which ,Qf the respective magnetic clutches 111 or 115 are to be operated to give the desired feed. Accordingly the single switch 125 is adapted to close on the circuit 9,

and by means of an intermediate connecting. lead wire 126, the circuit is carried to the switch 127, which is shown as a two-way switch adapted to close on contacts 47 or 48 for the corresponding circuits to the respective clutches 111 for toward (S) or from (N) feed of the tool with respect to the work.

The same circuit (9) from the relay may beclosed through a switch 128 and interconnected to lead 129to the two-contact switch 130 adapted to complete the return circuit 9 through the contacts 27 or 29 for the corresponding circuits to the clutches 115, for

transverse feed; either to the left (W) or to the right (E) according to the direction of feed required.

For adjusting the tool manually for rough cuts or in preparation for automatic feed, it is desirable to provide for operatingjthe respective lead screws 109 and 113, the same as would ordinarily be done by the usual hand cranks. For this purpose the respective magnetic clutches 111 and 115.are adapted to be operated directly by manual switches, which shunt the relay 123. For direct control. therefore, the single switch 131 may be used to connect the positive side of-the main line; circuit 7 with contacts 47 or 48 of the corresponding circuits to the magnetic clutches 111 for toward or from feed according to'which contact closed.

Similarly switch 1'32 may be operated to connect the main line circuit 7 directly tov either circuits 27 or 29, the respective circuits to the clutches 115 for the transverse feed, either to the left or to the right, as may be required.

For the automatic operation of the respective feeds, the single relay 123 for clos-' ing the 110 volt circuit to the clutches, is

adapted to be operated on a relatively low potential (14 volt) circuit by means of the reciprocating work table, the control for automatic feed being so arranged that the feed is effected only during the non-cutting stroke. The source of the 14 volt ciirrent is indicated at 133-, the generator being grounded at 134, while the other side of the low voltage circuit 56 is carried to a contact 56 of the main switch 135, which is shown connected to the main line (110 volt) switch 121, so as to be operated simultaneously therewith. This switch (135) I connects the circuit 51 with the clutch operating relay 123, as indicated in Fig. 3, the other terminal of the relay being connected through lead 61 to a contact brush 136 adapted to complete the circuit through a commutator 137 having a wedge shaped conducting segment 138 and a grounded contact brush 139 cooperating therewith, when the commutator is rotated.

The commutator brush 136 by cooperating with the'wedge-shaped conducting segment 138 is adapted/to vary the length of time the circuit for operating the relay 123 isclosed, the length of time being determined according to the position of the contact brush 136 longitudinally of the commutator surface. The brush 136 is accordingly mounted for adjustment longitudinally of the wedge segment to change the length of circumferential are engaged by the contact brush 136 according to thefeed required. Furthermore, it is essential to have the feed take place only during the non-cutting stroke, and for this purpose 'the commutator 137 is adapted to be rotated at a predetermined speed for a single rotation during the non-cutting stroke, the release of the commutator being controlled-by the reciprocating planer tableiand suitable intermediate releasing device.

For rotating'the commutator 137 and releasing it for" a single rotation, the mecha- 'nism preferably employed is more particularly shown in Figs. 1 and 2,.although it will be understood that the timing and limiting of the feed may be effected by other suitable mechanism. The commutator 137 is mounted loosely upon a shaft or rod 140 supported in frame brackets 141 and prevented from rotation by a pin therethrough at 142. A worm wheel 143 is also mounted upon the shaft 140 and between the worm wheel and a flange 144 on-the commutator,

there is preferably mounteda cork disc or washer'145 to serve-as a friction drive between the worm wheel and the commutator. The cork disc 145 isheld in frictional en-- g'agement with the driving wheel 143 by a spring 146 thrust-ing against a ball bearing- 147 mounted -at the opposite end of the commutator, as will be seen in Fig; 1. Y

The commutator 137 is preferably provided with an escapement disc .148 secured to the right hand end thereof, asshown in Fig. 1, the disc being provided, in the present instance, with a single-detent notch 149, as shown in Fig. 2. A detent latch 150 located at the upper end of an armature lever 151 pivoted at 152, is adapted to engage the disc notch 149 and prevent rotation of the commutator .137. The cork friction 'disc 145 permits the commutator to be thus held against rotation, while the worm wheel 143 is rotated continuously during the operation of the machine, preferably by gears 153 and 154 from-the shaft 155 of a motor generator 156, whichin the present instance, is pref-- erably the motor generator indicated at 133 for supplying the 14 volt circuit for operating therelay 123.

To release the commutator137 for its single rotation, the detent 150, normally engaging the notch 149 of the disc 148, is adapted to be operated by an electro-magnet 157, the circuit of which is closed by a spring finger switch 158 through the circuit 60, as shown in Fig. 3. In order to close the spring finger switch-158, a closing bar 159 for cooperating with the spring fingers is carried upon a spring actuated lever 160, pivoted at 161 and adapted to be operated by the reversing mechanism of the planer. For this purpose,

a cam plate 162 is mounted on the shaft 163 of the usual planer reversing mechanism, the cam plate being provided with an operating finger 164 adapted to cooperate with an adjustable dog 165, locatedin convenient posiltion on the reciprocatingwork table 102.. The reciprocating table will operate the rever'sing mechanism in the usual way and rock the cam plate 162 and throw in the switch bar 159 to complete the circuit (60) at the end of the cutting stroke, the return circuit being completed through the ground at 166.

' Upon closing the circuit through the switch 158, the magnet 157 will be energized to attract the armature 151. the detent 150 of which is normally held in engagement with the notch 149 by a spring 167, and release the disc 148 for rotation with the associated commutator 137, by means of the friction drive of the continuously rotating; worm' wheel 143.

It will be understood that since the switch closing bar 159 is operated by the planer reprovided with an armature 169 which is normally held away from the magnet by a spring 170, thereby closing the circuit 60 through the armature (169) and the connecting circuit 44 to one terminal of the magnet 157, the other terminal being connected to circuit 51. As soon, however, as the magnet 157 is energized, the detent carrying armature lever 151 will close the circuit 91 at 171 to energize the auxiliary magnet 168, which in turn will attract its own armature 169 and break the circuit 44 to the magnet 157, at the same time closing the circuit 60 through the armature 169 and circuit 91 of the magnet 168 so that this circuit will remain closed and continue to energize the magnet 168 until the switch bar 159 is withdrawn to break the circuit of the spring finger switch 158.

From this, it will be seen that immediately following the release of the commutator disc 148 and the closing of the circuit (91) through the magnet 168,the detent 150, after releasing the commutator for its single rotation, will be released so that under the action of its spr ng 167, it will be restored to normal position to again engage the notch 149 in the iiisc, thus limiting the commutator 137 to a single rotation each time the switch 158 is during the non-cutting stroke.

closed by the reciprocating table 102, and obviously, this single rotation will occur only From the wiring,dia ram, Fig. 3, it will be seen that low potential current in circuit 51 is utilized for operating the control magnets 157 and 168, the return circuit 60 of I 4 which is completed through the ground 166 35' 7 when the switch 158 is closed.

As previously pointed out, the low potential operating circuit (51 -61) of the relay 123 for closing the single main line circuit (79) for operating the magnetic clutches, is adapted to be completed through the commutator brush 136, segment 138 and brush 139 to ground when the commutator is rotated so as to bringthe surface of the wedge-shaped conducting segment 138 into contact with the brush 136. The grounded brush 139 remains continuously in conducting engagement with the conducting segment 138 through an annular extension, and the brush 136 rests normally on an insulating portion of the commutator when held from rotation by the detent 150. However, during the single rotation, the brush 136 engages the surface of the conducting segment 138 and completes the circuit for a predetermined length of time, according to the position of the brush 136 lengthwise of the wedge-shaped segment. When the brush 136 is near the pointed end of the conducting segment 138, as indicated in Fig. 3, the duration of the contact will be very short and hence the magnetic clutches 111 or 115 would be energized for a minimum amount of feed; while if the contact brush 136 is moved to the left, as indicated in Fig. 3, to the widest part of the wedge segment 138, the relay 123 will remain closed for a complete or nearly complete rotation of the commutator and thus prolong the energization of the respective magnetic clutches, so as to give the greatest amount of feed. For shifting the contact brush 136 longitudinally of the armature, it is preferably mounted upon abracketarm 172, provided with a rack 173, with which a pin ion 174 cooperates, the latter being rotatable by means of a knurled head 175 to position the brush along the segment 138 and vary the feed accordingly. It will be understood, however, that the speed of rotation of the commutator 137 can bechanged by suitable intermediate change gearconnections (153154) to provide for a wide range of variability in the amount of automatic feed to be given to the tool through the magnetic clutches.

From the above, it will be seen that in operation, the automatic feed of the tool relative to the work is effected during the noncutting stroke by closing the single circuit to the'magnetic clutches operating the respec- 'ly of the control of the reciprocating table or the single circuit closed by the relay 123. The switch 131 may housed in this manner to operate either the N or S clutch 111 for moving the tool from or toward the work, and the switch 132 may be similarly used for actuat ing the clutches-115, E or W, for transverse motion of the tool to the right or left.

After suitable adjustment in this manner, the automatic feed, which is ordinarily step by step transverse feed for the successive cuts, may be established by first closing switch 128, then closing switch to either 27 or 29, according to whether the transverse feed is to be to the left or to the right.

If the automatic feed is to be by lead screw 109, the switch 125 is closed and then the switch 127 is closed to circuit 47 or 48 according to .whether step by step feed is to be toward or from under the control of the commutator 137. For operation under either manual or automatic control, obviously, the main switch (121435) should be closed.

The amount of automatic feed may be regulated, as previously pointed out, by the position of the contact brush 136, relative to the commutator conduct ng segment 138 and the position thereof may be adjusted by means of the knurled head so that a greater or lesser amount of the circumference of the conducting surface is brought into engagement with the brush 136 at each single rotation of the commutator to give the desired feed. 7

It will be understood that while the preferred form of the improvement has been shown, various modifications in the specific details of construction and arrangement of circuits may be made without departing from the spirit and scope of the invention.

We claim 1. An electrical feed forplaners comprising in combination, a pair of magnetic clutches for toward or from feed of the tool, a pair of magnetic clutches for right or left transverse feed, a single electric circuit adapted for operating said magnetic clutches, a relay for closing said circuit, means controlled by movement by the reciprocating table of the planer for operating said relay to close said clutch operating circuit for a predetermined length of time, a manually operable switch for closing said circuit in selecting toward or from feed and a second switch adapted to be closed in conjunction with said first named switch for placing in sa'd circuit the individual clutch selected foreither toward feed or from feed.

2. An electrical feed for planers as in claim 1, wherein a third manually operable switch is provided for closing said operating circuit and eliminating the relay by shunting its circuit and thereby efl'ecting either toward or from feed independently of automatic feed through said relay.

3. An electrical feed for planers comprising in combination magnetic clutches for toward or from feed, magnetic clutches for right or left transverse feed, a single circuit for operating any of said magnetic clutches selected according to the desired feed, a relay for closing said circuit for operating the respective clutches, means controlled by the reciprocating table for operating said relay, a manually operable switch for placing the clutches for transverse feed in said circuit and a second manually operable switch adapted to be closed in'conjunction with the first named switch for placing in operation he selected clutch for right or left transverse eed.

4. An electrical feed for planers as in claim 3, wherein a third manually operable switch is provided for closing said operating circuit drectly to the magnetic clutch for either right or left transverse feed and cutting out said relay. I

' JOHN C. ,SHAW.

. ROBERT DQ SHAW.

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