US2699606A - Attachment for pantograph engraving and copying machines - Google Patents

Description

A. BREAU ATTACHMENT FOR PANTOGRAPH ENGRAVING AND COPYING MACHINES Filed Dec. 3, 1951 3 Sheets-Sheet l INVENTOR. ANTHONY BREAU STLQW ATTORNEY.

Jan. 16, 1955 A. BREAU 2,699,606

ATTACHMENT FOR PANTOGRAPH ENGRAVING AND COPYING MACHINES Filed Dec. 3, 1951 6 Sheets-Sheet 2 FiG. 2

IN VEN TOR.

, ANTHONY BREMJ ATTORNEY.

Jan. 18, 1955 A. BREAU 2,699,606

ATTACHMENT FOR PANTOGRAPH ENGRAVING AND COPYING MACHINES Filed Dec. 3, 1951 3 Sheets-Sheet 3 ATTORNEY.

United States Patent ATTACHMENT FOR PANTOGRAPH ENGRAVING This invention relates to attachments for pantograph engraving and copying machines and more particularly to an improved stylus carried control for such machmes Various types of pantograph engraving and copying machines have heretofore been available in which a vertical rotary externally driven cutter spindle is provided on one arm of a pantographwith a stylus on another arm of the pantograph.

The stylus is adapted for manual tracing of an engraved cutout or other design or pattern previously laid out on a master plate or pattern plate for the purpose of reproducing the same design or pattern on the work and in the desired size ratio.

By adjustment of the mountings of the cutter spindle and the stylus with respect to the pantograph arms, the size ratio of the transfer from the master plate or pattern plate to the work can be readily varied as desired.

It has also heretofore been proposed to employ a spring returned depth regulator as a mounting for the cutter spindle, which depth regulator has provisions for ad ustment of the depth of cut by limiting the permissible downward movement of the cutter.

In the operation and use of the machines now available on the market, it is necessary, in most instances, for the operator to use two hands, one to actuate or position the stylus and the other to advance the cutter downwardly to the work. With machines of this type, there are necessarily size limitations to permit of this type of manual actuation but in all sizes the positioning of the hands and arms of the operator quickly brings on a condition of fatigue and decline of proper careful control of the cutter.

Various types of control have heretofore been proposed but none of these has proven satisfactory. Accidental downward movement of the stylus at an undesired location in the machines of this type now available frequently occurs and usually results in spoilage of the work.

It is the principal object of the present invention to provide an attachment for pantograph engraving and copying machines by which the control of the positioning of the cutter spindle is effected by and from the stylus.

It is a further object of the present invention to provide an attachment for pantograph engraving and copying machines in which the cutter spindle is only actuated to or maintained in a cutting position-for predetermined positions of the stylus.

It is a further object of the present invention to provide an attachment for pantograph engraving and copying machines in which a predetermined range of movement of the stylus is utilized to position the cutter and actuating movement is not permitted except at locations corresponding to portions of the master plate or pattern plate which are to be copied or transferred.

It is a further object of the present invention to provide, in an attachment of the character aforesaid, an improved solenoid control of the positioning of. the cutter, with an adjustable dashpot for regulating the speed of advance of the cutter to the work. i

It is a further object of the present invention to provide an attachment of the character aforesaid in which a retarded solenoid action is employed for downward or advancing movement of the cutter with a spring for upward or return movement of the cutter.

It is a further object of the present invention to provide, in an attachment of the character aforesaid, a stylus which may be utilized at any desired level over a relatively wide range of positions Without the necessity for adjulstments to accommodate the stylus to the desired leve It is a further object of the present invention to provide an attachment of the character aforesaid, having improved visibility of the tracing end of the stylus.

Other objects and advantageous features of the invention will be apparent from the specification and claims.

The nature and characteristic features of the invention will be more readily understood from the following description, taken in connection with the accompanying drawings forming part hereof, in which Figure 1 is a top plan view of a portion of a pautographic engraving and copying machine with the attachment in accordance with the invention applied thereto;

Fig. 2 is a fragmentary sectional view of the machine ignd alttachment, taken approximately on the line 2-2 of Fig. 3 is an enlarged vertical central sectional view of a preferred form of stylus and mounting therefor forming part of the present invention, and taken approximately on the line. 3-3 of Fig. 1;

Fig. 4 is a horizontal sectional view, enlarged, taken approximately on the line 44 of Fig. 3; and

Fig. 5 is a diagrammatic view showing the electrical circuit connections for the control of the cutter spindle and illumination of the stylus end.

It should, of course, be understood that the description and drawings herein are illustrative merely and that various changes and modifications may be made in the structure disclosed without departing from the spirit of the invention.

Referring now more particularly to the drawings, a pantograph machine is shown generally at 10 with a frame a 11 on which a work piece 12 is adapted to be secured at one location by clamp bolts 12a and a master plate or pattern plate 13 is adapted to be secured at another location by clarnp bolts 13a.

The frame 11 also has supported thereon by means of a vertical pivot pin 14, an adjustable parallelogram pantograph 15 having a pair of parallel arms 16 and 17 and a pair of parallel arms 18 and 19. The arms 16 and 19 are pivotally connected by the pivot pin 14, the arms 16 and 18 are pivotally connected by a pivot pin 20, the arms 17 and 18 are pivotally connected by a pivot pin 21, and the arms 17 and 19 are pivotally connected by a pivot pin 22. The pivot pins 20 and 21 are carried in brackets 23, adjustable along the arms 16 and 17, and the brackets 23 are clamped at the desired location for a selected pantograph ratio by clamping studs 24. The pantograph arm 17 has a forward extension, as seen in Fig. 1, on which the stylus assembly is mounted, as hereinafter explained.

The machine frame 11 also has mounted thereon an electric motor 25, with a pulley 30 on the motor shaft. The pulley 30 is connected by a driving belt 31 to a pulley 32, mounted on a shaft 33 which is pivotally supported on the frame 11 by a bracket arm 34 of telescoping type and adjustable in length.

- The shaft 33 also has mounted thereon a pulley 35 secured to and driven by the pulley 32, the pulley 35 being connected by a belt 36 to a pulley 37 which drives 'a hollow cutter spindle 38.

The spindle 38 is supported by a bracket 39 which is mounted on the pantograph arm 18 and is adjustable therealong and secured in adjusted position by studs 40, for varying the pantograph ratio.

A link 41, adjustable in length, is interposed between the shaft 33 and the spindle 38 to position the shaft 33 upon movement of the pantograph 15 about the axis provided by the pivot pin 14.

The cutter spindle 38 is mounted in an adjustable spring returned depth regulator 42 of the cam lever type,and with an outwardly extending cam lever 43, which was heretofore utilized for manual operation, movable in a cam groove 44, by which the downward movement of the cutter spindle 38 is effected. The cutter spindle 38 has removably mounted therein any desired type of cutter 45, in accordance with the character of engraving or cutting desired on the work piece 12 and the material of which the work piece 12 is composed.

The foregoing pantograph machine is well known in the art and has been included and described so that the construction and operation of the attachment, in accordance with the present invention, may be more readily understood.

As shown in Fig. .1, a bracket 50 is provided on the outer end of the pantographarm 17 which has a vertical bore 51 in which a stylus assembly 52 is carried.

The stylus assembly includes a vertically disposed body portion 53, preferably of light transmitting synthetic plastic such as an acrylic resin, and preferably has a small lamp 54 mounted in an opening 55 therein. The body portion 53, at the lower endthereof, has an inclined face 53a for directing the transmitted light from the lamp 54 a'ngularly and onto the end of a foot 55 which is secured to the body portion 53 in any preferred manner, such as by bolts 56.

. At the upper end of the body portion 53, a horizontal extension 57, is provided, the upper face of which serves as an abutment for one end of a compression spring 58. The other end of the spring 58 is in engagement with and may be secured in an abutment block 59 having a lower threaded end 60. a

A cylindrical stylus sleeve 61 is provided within which the end 60 of the block 59 is in threaded engagement at its upper end, the stylus sleeve having a hollow interiorly threaded section 62 extending to the upper end. The stylus sleeve 61 extends through the bore 51 and is movable vertically therein, as hereinafter explained.

. At the lower end of the body portion 53, a horizontally extending guide plate 63 is provided, within which the lower end of a stylus sleeve 61 extends for downward movement. The lowermost portion 64 of the stylus sleeve 61 is preferably frusto-conical.

The internally threaded section 62 has mounted therein, at the lower end thereof, a spring abutment plug 65 which is adjustable in the section 62 by means of a transverse slot 66. A compression spring 67, in engagement at one end with the plug 66, is in engagement at its other end with an enlarged head 63 slidable in a bore 69 in the stylus sleeve 61'. The head 68 has a stylus pin 70 secured thereto and the stylus pin 70 has a lower end 73 for move ment into a groove, slot, depression or other pattern or design in the pattern plate or master plate 13 as hereinafter explained.

The stylus pin 70 is provided with a transversely extending locking or limit pin 75, which is movable in a transverse vertical slot 76 formed in the body of the stylus sleeve 61.

ln'order to limit the movement of the stylus pin 61 to a predetermined extent, a cylindrical limit sleeve 77 is provided, exteriorly disposed on the stylus sleeve 61 and with slots 78 for movement of the ends of the limit pin 75, the lower ends of the slots 78 limiting downward movement of the stylus pin 70, and the upper ends of the slots 78 limiting downward movement of the stylus sleeve 61 as hereinafter explained. By selection of or substitution of a limit sleeve 77 having a different length of slots 78 or by changing the position of the limit sleeve 77 vertically on the stylus sleeve 61, movement of the stylus pin 70 can be determined as desired.

Enclosing the limit sleeve 77, an actuating sleeve 79 is provided, held in position by a set screw 80, for manual sidewise movement of the stylus sleeve 61 and for manual downward movement of the stylus sleeve 61 when the same is permitted by the master pattern.

On the upper end of the abutment block 59 an electrical contact 81 is provided, which is normally in engagement with an electrical contact 82 carried by a conductor arm 83. The conductor arm 83 is carried by a bracket 84 secured to the body portion 53. The contacts 81 and 82 are capable of separation, upon downward movement of the stylus sleeve 61.

It will be noted that the stylus assembly 52 is movable vertically with respect to the stylus mounting bracket 50, by reason of the slidable mounting of the stylus sleeve 61 in the bore 51, and upon engagement of the foot 55 with the .upper face of the master plate or pattern plate 13, the stylus assembly may be employed at the desired level of operation without further adjustment.

It is to be noted, also, that when the stylus assembly is positioned by the foot 55 in engagement with the upper Surface of the master plate or pattern plate 13, the stylus pin 70 will be urged downwardly by the spring 67. If the end 73 of the stylus pin 70 is in engagement with the upper surface of the plate 13, the limit pin 75 will be held at the upper end of the slots 78. Downward movement of the stylus sleeve 61 will be prevented and disengagement of the contacts 81 and 82 is also prevented. If, however, the stylus sleeve 61 is positioned so that the end 73 moves into a slot, groove or other depressed design on the plate 13, downward movement of the stylus sleeve 61 and separation of the contacts 81 and 82 may be then effected.

Referring now to Figs. 1 and 2, the depth regulator 41 as there shown, preferably has an operating cord 88 connected to the cam lever 43. The cord 88 extends around a pulley 89 mounted on the bracket 39, carried by the pantograph arm 18, around a pulley 90 and is connected to an abutment 91 carried on the bracket 39. The pulley 90 is preferably carried in the bifurcated end of an armature 92 which is movable axially in and by a solenoid CS which is carried by a bracket 39a on the pantograph arm 18 and which is preferably held in position by one of the studs 40.

The armature 92 of the solenoid CS is in engagement, at the inner end thereof, with a piston actuator 94 which extends into a dash pot cylinder 95. The piston actuator 94 preferably has a cup leather 96 on the inner end thereof. A compression spring 93 is provided, having one end in engagement with the cup leather 96 and the other end in engagement with a cylinder head 97 within which an adjustable needle valve 98 is provided for controlling flow of air out of and into the dash pot cylinder 95, as desired.

Referring now more particularly to Fig. 5, the circuit arrangements are shown diagrammatically and include a pair of power leads 100 and 101 which are connected to any suitable source of electrical energy, but preferably to a L10 volt 60 cycle A. C. source.

One of the leads, such as the lead 100, is connected through a cut-off switch 102 and the other lead 101 is connected through a .fuse 103. The primary winding 104 of a step down transformer T is shunted across the leads 100 and 101. The secondary winding 105 of the transformer T is connected at one end thereof by a conductor 106 to the stylus contact 81. The other end of the secondary winding 105 is connected by a conductor 107 to one end of the winding of a stylus relay SR, the other end of the winding of the relay SR being connected by a conductor 108 to the conductor arm 83 and therethrough to the contact 82. The output voltage of the secondary winding 105 may be of the order of 6 volts.

The lamp 54 is preferably shunted across the conductors 106 and 107 and connected thereto by conductors 109 and 110.

The lead 100 extends to one terminal of the winding of the solenoid CS, the other terminal of the winding being connected by a conductor 11] to a contact 112 which is engageable by a movable contact 113 controlled by the armature 114 of the stylus relay SR. The contact 113is connected to the lead 101. A variable condenser 115 may be provided connected between the conductor 111 and the lead 101 for reducing sparking at the contacts 112 and 113. I

The winding of the solenoid CS is normally deenergized and the stylus contacts 81 and 82 are normally in engagement. The winding of the stylus relay SR is normally energized, and the contact 113 out of engagement with the contact 112.

Upon separation of the contacts 81 and 82 the winding of the stylusrelay SR isdeenergized and the contact 113 moved into engagement with the contact 112 to complete an energizing circuit for the solenoid CS.

Upon energization of the solenoid CS, the actuating cord 88moves the lever 43 to advance the cutter 45 downwardly for cutting.

The dash pot prevents excessively rapid downward movement of the cutter spindle 38 of a character which might injure thecutter 45, by reason of compression of air in the dash pot cylinder 95 and the controlled discharge permitted by the needle valve 98. Upon deenergization of the solenoid CS, the return spring in the depth regulator 42 and the return spring 93 in the dash pot cylinder 95 both act to, return the spindle 38 to its initial and'noncutting position. v I v By use of the cup leather 96, also, a more rapid return stroke of, the dash pot piston is effected since, upon the return movement, air can readily leak past the cup leather 96.

The mode of operation, it is believed, will be apparent from the foregoing, but may be summarized briefly.

With electrical energy supplied to the motor 25 in any desired manner for actuation thereof, the' pulley 310, through the belt 31 effects rotation of the pulley 32 which drives the pulley 35, and therefrom through the belt 36 effects rotation of the cutter spindle 38 and the cutter 45. The cutter spindle 38 and the cutter 45 are initially in a raised position as determined by the depth regulator" 42, and out of contact with the work piece 12.

When it is desired to perform a cutting operation with the cutter 45, the switch 102 is closed to complete an energizing circuit for the stylus relay SR, and to permit of energization of the solenoid CS, as heretofore explained.

The stylus assembly is then moved laterally to the desired location on the pattern plate or master plate 13, the pantograph shifting to permit of this movement and at the same time moving the cutter spindle 38 and cutter 45 to a corresponding location with respect to, but out of contact with, the work piece 12. The arms 34 and 41 shift the driving pulleys as the pantograph 15 is moved.

While such positioning is being effected, the foot 55 bears on the upper surface of the pattern plate or master plate 13, and accommodates the stylus assembly to the level of the master plate or pattern plate 13, the sliding of the stylus sleeve 61 in the bore 51 permitting movement to this extent.

The stylus pin end 73 normally rides over and is held up by the upper surface of the pattern plate 13, and in its upper position by the engagement of the limit pin 75 with the upper end of the slots 78 prevents downward movement of the stylus sleeve 61.

When the stylus sleeve 61 is moved to a location on the pattern plate 13, such as a groove, slot, or other undercut part of the master pattern or design, this permits downward movement of the stylus pin 70 so that the end 73 bottoms in the pattern groove or slot. Upon downward movement of the stylus pin 70, the limit pin 75 moves downwardly therewith to the lower end of the slots 78. The stylus sleeve 61 may then be moved downwardly by manual application of pressure on the sleeve 79, against the forces of the springs 58 and 67, thus separating the contacts 81 and 82. Upon the separation of the contacts 81 and 82, an energizing circuit is set up for the solenoid CS, as previously pointed out, and the cutter 45 is moved downwardly to a position to make the desired cut.

While in this downward position, if permitted by sidewise movement of the end 73 of the stylus pin 70, an elongated, arcuate, or other out may be made, as determined by the design on the master plate or pattern plate 13. Upon reaching the extremities of a groove, slot or other recessed portion of the design on the pattern 13, if the stylus sleeve 61 is moved so as to push the end 73 of the stylus pin 70 out of the slot or groove, the stylus sleeve 61 will be moved upwardly upon engagement by the limit pin 75 with the upper ends of the slots 78. Upon upward movement of the stylus sleeve 61, either in this manner, by manual release of the sleeve 79, or in any other manner, so that the stylus sleeve 61 is impelled upwardly by the spring 58, the contacts 81 and 82 are engaged, and upon such engagement the stylus relay SR is energized, thus breaking the contacts at 112 and 113 and deenergizing the solenoid CS.

Upon such deenergization of the solenoid CS, the armature 32 is returned to its initial position, and the cutter 45 is quickly retracted from its cutting position.

It will be particularly noted that, by reason of the control of the stylus sleeve 61 by the stylus pin 70, no false out can be made by accidental downward movement of the stylus sleeve 61, or upon movement out of the pattern groove or slot.

The working portions of the stylus pm 70 and foot 55 are illuminated by light supplied from the lamp 54 and delivered by the face 53a onto the master plate 13 at the location where the stylus is employed.

I claim:

1. An attachment for pantograph engravlng machines having a driven cutter carried by one of the pantograph arms and having actuating means for advancing said cutter towards and retracting said cutter from the work comprising stylus means carried by another of said pantograph arms for controlling said actuating means, sald stylus means including a body portion, a foot member on said body portion for positioning said body portion with respect to said arm, a stylus pm having a tracing end,

a holder movably mounted in said body portion in which said stylus pin is mounted, a resilient member in said holder normally urging said pin outwardly with respect to said holder, a liniit member movable with said stylus pin, an additional limit member carried by said holder and having spaced portions with which said firstlimit member is engageable, said limit members preventing butward movement of said holder when said stylus pin" is at its inward position.

2. An attachment for pantograph engraving machines having a driven cutter carried by one of the pantograph arms and having actuating means for advancing said cutter towards and retracting said cutter from the work comprising stylus means carried by another of said pantograph arms for controlling said actuating means, said stylus means including a body portion, a foot member on said body portion for positioning said body portion with respect to said arm, a stylus pin having a tracing end, a holder movably mounted in said body portion in which said stylus pin is mounted, a resilient member in said holder normally urging said pin outwardly with respect to said holder, limit members on said pin and said holder preventing outward movement of said holder when said stylus pin is at its inward position, and contacts controlled by movement of said holder for controlling said actuating means.

3. An attachment for pantograph engraving machines having a driven cutter carried by one of the pantograph arms and having actuating means for advancing said cutter towards and retracting said cutter from the work comprising stylus means carried by another of said pantograph arms for controlling said actuating means, said actuating means having a solenoid operator, said stylus means including a body portion, a foot member on said body portion for positioning said body portion with respect to said arm, a stylus pin having a tracing end, a holder mounted in said body portion in which said stylus pin is mounted, a resilient member in said holder normally urging said pin outwardly with respect to said holder, limit members on said pin and said holder preventing outward movement of said holder when said stylus pin is at its inward position, and contacts controlled by movement of said holder for controlling said solenoid operator.

4. An attachment for pantograph engraving machines having a driven cutter movable towards and away from the work and mounted on one of the pantograph arms comprising means on said pantograph. arm for positioning said cutter, stylus means on another of the pantograph arms, said stylus means including a body portion movable with respect to said other arm towards and away from a pattern plate, a foot member on said body portion having a contact surface engageable with the face of the pattern plate for positioning said body portion with respect to said other arm, a holder mounted in said body portion and movable with respect to said foot member, said holder being movable with respect to said other arm towards and away from the pattern plate, a stylus pin slidably mounted in said holder for inward and outward movement, a resilient member in said holder normally urging said stylus pin outwardly with respect to said holder, movement limiting means interposed between said pin and said holder for preventing outward movement of said holder when said pin is inwardly disposed, and operating connections between said holder and said cutter positioning means.

5. An attachment for pantograph engraving machines having a driven cutter mounted on one of the pantograph arms and having actuating means for advancing the cutter towards and retracting said cutter from the work comprising stylus means on another of the pantograph arms, said stylus means including a body portion movable with respect to said other arm towards and away from a pattern plate, a foot member on said body portion having a contact surface engageable with the face of the pattern plate for positioning said body portion with respect to said other arm, a holder mounted in said body portion and carried by said other arm and movable with respect to said foot member and said other arm towards and away from the pattern plate, a stylus pin slidably mounted in said holder, movement limiting means interposed between said pin and said holder for preventing outward movement of said holder when said pin is inwardly disposed, and operating connections between said holder and said actuating means.

References Cited in the file of this patent UNITED STATES PATENTS Ellinwood July 10, 1877 Reinhardt May 21, 1895 5 Diss June 8, 1909 Ziegler Nov. 2, 1909 Turner Oct. 23, 1923 Smith et al. Apr. 26, 1927 Rennick Feb. 9, 1932 10 Young Sept. 5, 1939 Turchan et a1 Nov. 10, 1942 Iwanowicz Feb. 16, 1943 Geibig May 30, 1944 FOREIGN PATENTS Germany Sept. 17, 1915 France June 7, 1943 Switzerland Dec. 1 7, 1945

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