US2394558A

US2394558A - Electric control means for veneer clippers

Info

Publication number: US2394558A
Application number: US560757A
Authority: US
Inventors: William J Miller; Alfred C Johnson
Original assignee: ELLIOTT BAY MILL CO
Current assignee: ELLIOTT BAY MILL Co
Priority date: 1944-10-28
Filing date: 1944-10-28
Publication date: 1946-02-12
Anticipated expiration: 1963-02-12

Description

Feb. 12, 1946. w. .1. MILLER ETAL ELECTRIC CONTROL MEANS FOR VENEER CLIPPERS Filed Oct. 28, 1944 3729 20 3 3 4 se 8 23 se g "ivry, .35 24 2@ 39 6l 42 59 2l A 58 6 25 5/ HH ,n

r/ INVENTpR. saws; 21M/m f/w//ff 50 BY /f/ea CdM/ps0 57' @@ww 52 E92 flfofr/Vfy Patented Feb. 12, 1946 ELECTRIC CONTROL MEANS FOR VENEEB CLIPPERS William J. Miller and Alfred C. Johnson, Seattle,

Wash., Seattle, Wash.,

assignors to Elliott Bay Mill Co.,

a corporation of Washington y Application October 28, 1944, Serial No. 560,757

9 Claims.

'Ihis invention relates to electric control means for a veneer clipper or any strip cutter or clipper and an object of this invention is to provide simple and efllcient means for automatically controlling a veneer clipper so as to cut veneer into pieces of predetermined standard widths or to selectively cut the veneer into random widths selected by an operator.

'I'he present invention is in the nature of an improvement on the control means disclosed in the co-pending application of William J. Miller, Serial No. 484,673, flied April 26, 1943. Y

In the manufacture of plywood the veneer is removed from the log in a continuous sheet by a veneer lathe or peeler and is fed directly to a clipper by which it is cut up into the pieces that are to be used in making the plywood. As the peeled veneer comes from the log it will usually be of varying quality with portions that are suitable for use and other portions that must be cut out and discarded because of pitch pockets knots or like defects that render these portions unsuitable for use. When a substantial run of usable veneer comes from the lathe in a continuous strip then it is desirable to eut this usable portion into standard widths, such as twentyfour, thirty, thirty-four or forty-eight inches. However, to utilize the Veneer" stock most efliciently and salvage pieces of usable veneer that are less than the minimum standard width, it is desirable to give the operator complete control so that he can suspend the automatic operation and cut the veneer at any desired location at any time he Wishes.

It is an object of this invention to provide a control means of simple and durable constructrol means constructed in accordance with this invention showing the same in connection with a veneer clipper and veneer feeding means.

Fig. 2 is a sectional view on a larger scale than Fig. 1 taken substantially on broken line 2-2 of Fig. 1 and showing an electric control box with a movable contact arm therein in an upright p0- sition.

Fig. 3 is an elevation of the outer or front side of the electric control box.

Fig. 4 is an elevation of said control box as it would appear with the cover plate removed.

Fig. 5 is an elevation looking at the inside of the cover plate of the control box.

Fig. 6 is a sectional view through the control box taken substantially on broken line 6-6 of Fig. 3.

Like reference numerals designate like parts throughout the several views: y

This control means is adapted for use in con;

nection with a veneer clipper of the type distion which meets all of the above Vstated requirements and gives the operator complete control of the cutting of the veneer.

It is another obj ect of this invention to provide a control means that is quickly and easily adjustable for the cutting of veneer strips of various standard widths. v

It is another object of this invention to provide control means of this nature including an electric contact arm movable over a plurality of contacts and connected with a veneer clipper knife so that said contact arm will be moved back to a zero or starting position each time the knife makes a cutting stroke.

Other objects of this invention will be apparent from the following description taken in connection with the accompanying drawing.

In the drawing:

Fig. 1 is a diagrammatic view of electric conclosed in the prior patent application of William J. Miller, hereinbefore referred to. Parts of such a veneer clipper are diagrammatically shown in Fig. 1. In such a clipper the veneer I0 as it comes from the log is fed by veneer feeding means II across a die or bed block member I2. A reciprocable knife I3 is operatively supported by toggle lever means 8 and disposed so as to cut against the bed block I2 and clip the veneer I0 that is passing across and supported by said bed block.

Link members 8, one of which is shown in Fig. 1, are rigidly connected at one end with the knife I3 and at the other end with a rockingly mounted bar or shaft 1. This member 'l is hereinafter referred to as a rock shaft and it oscillates every time the knife is stroked. This oscillating rock shaft is utilized as a means for moving a contact arm, hereinafter described, back to a starting position each time the knife I3 is stroked.

The knife I3 is reciprocably moved by electrically controlled means, such as by a piston I4 in a pneumatic cylinder I5. Air under pressure to move the piston I4 is supplied through an air inlet conduit I6 to a valve I1. The valve I1 controls the flow of said air under pressure through other conduits I6 to the cylinder I5. The valve I1 is of standardconstruction and is more fully illustrated in the co-pending application hereinbefore referred to. Electrically operated means, such as a double acting solenoid I8 is provided to operate the air valve I1.

An automatic control device constructed in accordance with this invention includes a main opening 59 in black plate 22. ljournaled in a bearing I of a mounting bracket housing part 20, a cover plate 2i for'the front of housing 20 has its central portion cut away to provide a cavity 23 for the operation of a contact arm 24. The contact arm 24 is rotatively mounted on a shaft 25 that extends through an The shaft 25 is 52. A clutch plate 53 is xedly secured, as by a nut 54, to the forward end portion of the shaft 25 and frictionally engages the face of the contact arm 24. A compression spring 55 is disposed on the shaft 25 between the back face of the contact arm 24 and a ball thrust bearing 54. The ipring 56 yieldingly holds the clutch plate 53 in contact with the contact arm 24. This provides a friction connection between the contact arm 24 and shaft 25 so that the contact arm 24 can be moved by rotary movement of the shaft 25 or'can be moved independently of the shaft 25 by slipping said contact arm relative to the clutch plate 63. This provision for slippage between the contact arm and the disc 53 allows the contact arm to be moved back to a starting position while the disc is being moved in an opposite direction by movement of the veneer I9, as

hereinafter described.

` The contact arm 24 is preferably made of insulating material and has two

contact brushes

26 and 21, Fig. 4, that are electrically connected with each' other by conductor means 26.

The cover plate 2l hasl an arcuate slot 29 for receiving and guiding a plurality of adjustable contact members designated generally by

numerals

3i, 32, 33, and 34. One end portion of the slot 29 is enlarged to provide an opening 39 through which the

contact members

3i, 32, 33 and 34 may be introduced into this slot.

Each of the contact members 3|, 32, 33 and 34 is made up of a medial portion 35, Fig. 2', of proper dimensions for a sliding iit in th'e slot 29. A contact button 36 is provided on the inner end portion of the part 35 and a head member 31 on the outer end portion of said part 35.

Parts

36 and 31 are wider than the slot 29 to prevent removal of the contact members except by bringing them into alignment with the enlarged end portions 30 of the slot 29. 4

l The head part 31 of each contact member has a` groove 38, Fig. 2, to receive the peripheral portion of an adjusting disc 39. The adjusting discs 39 are all threaded ontoan arcuate screw member 40 that is positioned in front of the slot 29 and is secured, as by brackets 4I to the outer face of the cover 2l. The contact members 3|, 32, 33 and 34 are readily adjusted by turning of discs 39. The discs 39 bind snugly on the screw 49 and may be further locked thereto by nuts 39' if desired. I

A fixed arcuate contact member 42 is provided on the inner side of the cover plate 2I,as best shown in Fig. 5. This contact member 42 is continuously in electrical contact with the lower contact brush 26 of the contact arm 24.

Bolts 43 may be used to secure the front and back cover plates 2| and 22 and main housing 20 in assembled relation. Cap screws 51 may be used to secure the

housing

20, 2I, 22 to a supporting bracket 52.

A sprocket wheel 44,` shown diagrammatical- 1y by broken lines in Fig. 1, and shown by full lines in Fig. 2, is mounted on the shaft 25 externally of the housing 20. A link belt 45, also 4assauts shown diagrammatically by broken lines in Fis.

1 is used to connect the sprocket wheel 44 with another sprocket Wheel or pinion 46 that is rigidly connected With a measuringwheel 41. The measuring wheel 41 runs on the veneer and always tends to move the contact arm 24 in synchronism-with the veneer.

A shaft o r spindle 46 common to pinion 46 and measuring wheel 41 is supported in an upright bracket 49 that extends upwardlyand is slidable in a xed guide 49'. A compression spring I9 exerts a yielding pressure tending to hold the measuring wh'eel down on the veneer I0. 'I'he measuring wheel 41 is rotated in a counter-clockwise direction, as respects the showing in Fig. l, by the traveling veneer I0 and will exert a constant force through link belt 45, sprocket wheel 44, shaft 25 and friction plate 53 tending to move the contact arm 24 in a counterclockwise direction. In the absence of slippage of the clutch plate 53 the movement of the contact arm 24 will be proportional to the movement of the veneer I.

However, means are provided for slipping the clutch plate 53 and returning the contact arm 24 to va zero or starting position each Vtime the knife strikes a cutting blow. The contact arm 24 is l shown in the starting position in Fig. 4. Preferably a resilient bumper 89 is provided to stop this contact arm in the starting position.

Various devices can be provided for returning th'e contact arm 24 to the Zero or starting position each time the knife is stroked. One satisfactory device for accomplishing this purpose comprises a pin 58 rigid with arm 24 and alink 59- connecting the pin 58 with a lever arm 69 'that is secured to the rock shaft 1. "Lost motion means are provided inthe connection between pin 58 and rock shaft 1. Oneway of providing this lost motion means is to provide a slot 5I in the portion of the link 59 that engagesfthe pin 58. This slot'6I and the

parts

58, 59 and 60 are proportioned and arranged so that the contact mem l ber 24 will always be moved to the starting posi@ tion in which it is sh'own in Fig. 4 when the knife I3A strikes a cutting blow on its downward movement and the link 59 will always be allowed to move to the left, Fig.` 1, on the retractile stroke of the knife without carrying the contact arm 2.4

back with it. Thus the contact arm 24 is always moved to a. starting position by the stroking of th'e knife I3 and can only be moved away from such starting position by the movement of the veneer I0 under the measuring wheel 41.

A plurality of manually

operable switches

62, 63, 64, 65 and 66, preferably of self opening type and diagrammatically shown as push botton switches in Fig. l, are provided for the use of an operator in controlling this apparatus. Each of `said switches has one terminal connected by conductor means 61 with one conductor 6B of a source of energycircuit: The other terminal ofthe switch 62 is connected by conductor 69 with one terminal of a relay 10, the other terminal of the i relay 10 is connected by conductor means "1I with the other conductor 12 of the source of energy circuit. y v

The relay 10 is of a diierential or ratchet type and controls an independent circuit through

conrductors

13 and 14. This relay 19 and the circuit controlled thereby are operative to energizel the solenoid I 8 so that it will. exert a force rst in one direction and then in the opposite direction. This operates the valve I1 so as to alternately admit air under pressure to oppositev ends ofthe cylinder I5 and vresults in the stroking of the minals of said switches 63, 64, 65 and 66 are re' spectively connected by

conductors

15, 16, I'I and 18 with the contact members 3|, 32, 33 and 34. These contact members are adapted to be successively engaged by the contact arm 24 as said contact arm 24 is progressively moved by the moving veneer and in synchronism with the movement of said veneer. Contact arm 24 is always in electrical contact with arcuate contact member 42 and this contact member 42 is electrically connected with relay 'I0 as by

conductors

19 and 69.

This automatic control device, in combination with the switches and circuits just described, enables an operator to control the knife I3 very accurately. Any time the switch 62 is closed the knife I3 will always be instantly operated. Any time one of the

switches

63, 64, 65 or B6 is closed a circuit will be completed by the progressively moving contact arm 24 andthe knife I3 will always be operated after the veneer has been advanced a predetermined distance from the position it occupied at the time of the preceding knife stroke, depending on which switch 63, 64, 65 or 66 was closed.

The peeled veneer, as it comes from the log, will usually be of varying quality with certain portions that are suitable for use and other portions that need to be cut out and discarded because they have pitch, pockets knots or like defects.

If the veneer that is passing under the knife I3 at a given time is free from defective portions that have to be discarded then the operator will hold one of the

switches

63, 64, 65 or 66 closed and the machine will operate automatically to cut at the predetermined intervals for which the closed switch is set. Usually in good veneer pieces will be cut to the maximum width, such as forty-eight inches. An experiencedoperator is able to judge very accurately as respects the number and width of pieces of good veneer to be obtained from a run of veneer between two defects. If the veneer calls for Athe cutting of pieces less than the narrowest standard width then the operator uses the switch 62 and in this way he can salvage a maximum amount of usable veneer but the narrower strips will not be of any standard or measured width.

'I'he circuits herein shown operate in response to the closing of switches but it is obvious that circuits could be provided which would operate by the opening of switches.

The foregoing description and. accompanying drawing clearly discloses what we now regard as a preferred embodiment of this invention but it will be understood that this disclosure. is merely illustrative and that changes may be made within the scope and spirit of the following claims.

We claim:

1. In a clipper and control therefor, a reciprocable knife; means for moving said knife to cut material; means for feeding sheet material past said knife; a controller having a contact arm movable over a plurality of contacts; means synchronized with said material feeding means for moving said contact arm over said contacts; and meansoperable by the cutting tact arm to a starting position. ,Y

2. In a clipper and control therefor, means for feeding sheet material; a movable knife; means for moving the knife to out the material; a controller having a contact arm movable over a plurality of contacts; means for moving the contact arm over the contacts in one direction insynchronism with the movement of the sheet material; and means synchronized with the knife v for returning the contact arm to a. starting position upon each cutting movement of the knife.'

3. In a clipper and control therefor, means for feeding sheet material; a movable knife; means for moving the knife to cut the material; a controller having a contact arm movable over a plurality of contacts; contact arm moving means frictionally connected with said contact arm and movable at a speed proportional to the speed of movement of the sheet material; and contact arm retracting means movable in synchronism with the knife to slip said frictional connection and retract said Contact arm to a starting position at each cutting 4movement of the knife.

4. A clipper and control therefor comprising continuously moving sheet material feed means; a movable knife; means for moving the knife to cut the material; a controller housing; a plurality of contact members in said controller housing; a shaft extending into said housing; a contact arm freely movable on said shaft from a starting position to a contacting position relative to said contact members; frictionv drive means frictionally connecting said shaft and said contact arm; means for driving said shaft in synchronism with the movement of the material; and contact arm retracting means movable in synchronism with the knife to slip said friction drive means and return said contact arm to the starting position at each cutting movement of the knife.

5. In an electrical control device, an angularly movable contact arm; contact arm moving means having a frictional connection with said arm; and means operable to slip said frictional connection and reversely move said contact arm.

6. In an electrical control device, a plurality of contact members, a contact arm movable over said contact members; and contact arm moving means having a frictional connection with said contact arm providing for the re-setting of said arm by the slipping of said frictional connection.

7. In an electrical contact device, a plurality of contact members; a contact arm; continuously driven contact arm moving means frictionally connected with said contact arm for moving said contact arm over said contact members; and contact arm retracting means connected with said contact arm and operable to retract said contact arm by slipping said frictional connection.

8. In an electrical control device, a housing a plurality of contact members in said housing; an angularly movable contact arm in said heus-- ing movable from. a starting position over successive contact members; continuously driven contact arm moving means frictionally connected with said contact arm for moving said contact sition by slipping said frictional connection. i

9. In an electrical control device, a housing;

a plurality of contact members in said housing;

a shaft extending into said housing; an angularmovement of said knife for returning s'aidtcon- I 1y movable contact arm in said' housing rotatable on said shaft and movable from a. startingr position over successive contact members: continuously driven contact arm moving means connected with said shaft; friction plate means rigid with said shaft and yieldingly engaging said contact arm for movingsaid contact arm away;1

from the starting position and over lsaid contact members in response to rotary movement oi' said shaft; and means for moving said contact arm back toa starting position by slipping said fric-A 15 tion plate means relative to said contact arm.

,l WILLIAW J. y C. JOHNSON.