US3300802A - Cutting machine - Google Patents

Description

H. R. POLLEYS CUTTING MACHINE Jan. 31, 1967 2 Sheets-Sheet 1 Filed Nov. 4, 1963 HHHH:

FIG, L

INVENTOR HERBERT R. POLLEYS BY M AGENT.

H. R. POLLEYS CUTTING MACHINE Jan. 31, 1967 2 Sheets5heet 2 Filed Nov. 4, 1963 mm mm o B g a 8 INVENTOR HERBERT R. POLLEYS BY gamed/ 4 34 AGENT.

United States Patent O Filed Nov. 4, 1963, Ser. No. 321,201 5 Claims. (Cl. 12-866) This invention relates to cutting machines comprising a mechanism for driving a cutting knife in a circuitous path around a pattern to cut articles from a sheet or slab of stock which is supported on a table plate and clamped against a cutting form during the cutting operation. In particular, the invention relates to machines which are adapted for single article cutting and which are actuated by repetitive operation of the actuating mechanism for each article cut.

In machines of the above type it is necessary, because of frequent changes of stock, to check the clamping pressure of the table plate as the plate forces and holds the stock against the form. With varying thickness and consistencies of material, this is desirable to assure adequate clamping pressure to prevent material slippage during the cutting operation which causes damage to the stock.

In prior machines it was necessary to operate a dual purpose single foot pedal in order to actuate the table lift cylinder for clamping the stock and also the clutch mechanism for driving the knife. In order to operate the table lift cylinder independently, without driving the knife around the pattern, it was necessary to disconnect either a mechanical linkage or some other clutch operating means. An alternative to disconnecting the linkage or other means was to shut off the source of power, thus resulting in a loss of production time. If none of the above precautions were taken, however, and the pedal were operated, the clutch would be engaged to drive the knife around its circuitous path during the lifting of the table and create a great hazard for the operator.

In my prior patent for an automatic sole cutting machine, United States Patent No. 3,006,006 issued on October 31, 1961, I disclose and claim a means for safely rotating the knife independently. This improvement over the prior art, however, does not provide means for safely and rapidly checking the table clamping pressure nor does the improvement relate to a single article cutting machine as does the present invention.

These and other objects are accomplished by providing the table lift cylinder of the cutting machine with a separately regulated source of pressurized fluid which is supplied to the cylinder through different sets of valves and conduits. One means channels the fluid through a threenot desired, but it is desired to only check the table clamping pressure or make other adjustments, the operator need only actuate a lever on a selector valve. This is the only operation necessary since a second means channels the fluid at the same pressure directly to the selector valve through a by-pass conduit and the fluid flows directly to the table lift cylinder. This eliminates the need to opearte the clutch actuating foot pedal. As a further safety measure a three-way normally open cut-off valve is placed in the fluid line to the clutch actuating cylinder between the foot pedal valve and the cylinder. This valve is operable by a fluid actuated normally closed pilot valve, fed from the by-pass conduit, and opened when the selector valve is opened to said conduit. When the pilot valve is opened it closes the valve inlet port from the foot pedal conduit, and exhausts the clutch cylinder conduit to atmosphere. This operation, thereby positively prevents the accidental operation of the clutch should the foot pedal be accidentally operated while the operator is checking the clamping pressure and entirely eliminates a hazard that has long existed in the sole cutting industry.

Other objects and advantages of this invention will become apparent from the following description used in conjunction with the accompanying drawings, wherein are set forth by way of illustration and example an embodiment of this invention.

FIG. 1 is a side elevational view of the improved sole cutting machine showing the position and inter-relationship of the parts thereof and embodying the invention; and

FIG. 2 is a schematic of the flow pattern showing the various fluid conduits, valves and cylinders of the machine shown in FIG. 1.

As shown in FIG. 1 of the drawings, this invention is illustrated in connection with a cutting machine of the type particularly disclosed in the United States patent to McGowan, No. 1,645,441 issued on October 11, 1927. The machine 10 comprises a cutting knife 11 which is driven around a templet or form 12 of the shape of the article to be cut from a sheet of stock 13, which is supported on a cutting pad 13. Stock 13 is clamped between templet 12 and pad 13' by reciprocating table 14.

Knife 11 is driven in a circuit around templet 12 by a carriage 15, which is directly connected to and driven by a chain 16 and guided in a circuit above templet 12 by upper and lower leaders or guide tracks 17 and 18, which are particularly shown and described in the United States patent to Patten, No. 1,270,319, issued June 6, 1922. Chain 16 is driven by a motor 19 through a clutch 20 which is operatively connected to the motor by a chain 21. If the engageable and disengageable parts 22 and 23 of clutch 20 are engaged, knife 11'is driven from clutch 20 through sprocket 24 and chain 24, which meshes with sprocket 25 keyed to shaft 26. Shaft 26' is driven by a slidable connection with shaft 26 and drives chain 16 through a bevel gear 27 which meshes with a bevel gear 28. Chain 16 passes over sprockets 29 and 30 and is driven by sprocket 30 which is rotatably mounted on a stud and aflixed to bevel gear 28.

Track guides 17 and 18 are slidably moved by a train of gears which are driven from shaft 26 by a gear 31 affixed thereto. Gear 31 is in meshing engagement with gear 32 which is keyed to a shaft 33, on which is keyed spiral gear 35. Gear 35 drives the train of gears 36, 37 and 38 which reciprocates track guides 17 and 18.

The improvement embodying the present invention, as shown herein, is a fluid operated system which is schematically shown in FIG. 2. Fluid enters the system under pressure, passes through shut-off valve 40, filter 41 and then branches off into two separate conduits 42 and 43. Conduit 42 has a lubricator 44 disposed therein and Patented Jan. 31, 1967 is connected to the input port of three-way normally closed valve 45 which is manually operated by a foot pedal 46. When it is desired to engage clutch 20 to thereby operate knife 11, foot pedal 46 is depressed by the operator and pressurized fluid enters one-way cylinder 47 through conduit 48, normally open three-way valve 49 (the operation of which will be later described), and conduit 48'.

The flow of fluid into cylinder 47 forces piston rod 50 upwardly to hold clutch 20 in engagement with the drive from motor 19 in a manner described hereinbelow. Motion is transmitted to the movable member 22 (FIG. 1) of clutch 20 through a linkage comprising bell crank lever 51 having an arm 52. Arm 52 yieldably actuates a rod 53 which is connected to one end of pivotally mounted lever 54 having a yoke 54' at its other end. Yoke 54' is connected to and actuates clutch collar 55 to cause the engagement or disengagement of clutch 20.

The second arm 56 of hell crank lever 51 is connected at its end to piston rod 50 and has a cam plate 57 integral with the free end thereof and extending upwardly in the direction of movement of piston rod 50.

A normally closed cam actuated three-way valve 58 is positioned so that valve operating lever 59 extends into the path of movement of cam plate 57 and is actuated !by the upward movement thereof. As piston rod 50 and cam plate 57 move upwardly the cam surface engages lever 59 and forces it to a valve opening position so that the pressure regulated fluid from conduit 43, which passes through pressure regulator 60, storage tank 61, lubricator 62, and branch conduit 63, enters the inlet port 64 of valve 58. Valve 58 is also equipped with an outlet port 65 and an exhaust port 66.

Outlet port 65 of valve 58 is connected by conduit 67 to an inlet port 68 of selector valve 69 which has a selector lever 70 for controlling the opening and closing of inlet ports 68 and 71. As shown in the solid line position of FIGS. 1 and 2, selector lever 70 is in the up position which opens port 68, while closing port 71, to permit passage of fluid from valve 58 through conduit 67, inlet port 68, and outlet port 72 in selector valve 69. Fluid passes from outlet port 72 to table lift cylinder 78 by way of conduit 73, flow control valve 74, conduit 75, quick exhaust or dump valve 76 and conduit 77. The pressure of fluid within cyclinder 78 forces piston 79 and attached table 14 upwardly to firmly clamp the stock for the cutting operation.

Releasing foot pedal 46 opens the exhaust port of valve 45 to atmosphere and thus allows clutch actuating piston rod 50 to return into cylinder 47 by means of an internal compression spring (not shown). This also shuts off table lift valve 58 from storage tank 61, when its cam roll lever 59 has returned by internal spring action to its down position. This at the same time opens exhaust port 66 to atmosphere whichreleases the pressure under table plate piston 79 allowing plate 14 to drop by gravity, The quick exhaust or dump valve 76 also open to atmosphere, giving an immediate accelerated table drop.

When it is necessary or desired to raise table plate 14 without the cutting operation being performed, to check clamping pressure or to make new settings for the stock thickness or consistence, hand lever 70 on selector valve 69 is moved to close off inlet port 68 and to connect inlet port 71 to by-pass line 80. This operation allows pressurized fluid from storage tank 61 to enter inlet port 71 via conduit 80 and to flow through outlet port 72 to table lift cylinder 78. It should be noted that this operation does not require the actuation of foot pedal 46. The entire table lift operation is performed merely by the actuation of selector lever 70. The regulated pressure in branch conduits 63 and 80 will remain constant and thereby impart the same pressure to table lift ylinder 78 as is used during the actual cutting operation.

An additional improvement is also provided that simultaneously provides an automatic and positive safety device to prevent knife block travel during the setting of the table stop (not shown) or checking of the clamping pressure by means of selector valve 69 as previously described. To accomplish this safety measure, two additional valves have been added to the above described new control unit circuit. Valve 81 is a normally losed threeway pilot valve that is positioned so that a cam plate 82 on selector lever 70 will operate an actuating plunger 83 when moved to the down position as shown in phantom in FIGS. 1 and 2. The downward movement of plunger 83 opens ports 84 and 85 in valve 81 so that fluid from by-pass conduit may pass via conduit 86 through valve 81 to conduit 87 to close by fluid pressure normally open three-way master valve 49 which is disposed between conduits 48 and 48'. Conduit 48' from clutch cylinder 47 is thus simultaneously vented to atmosphere, thereby preventing any pressure buildup in cylinder 47.

The closing of valve 49 thereby makes it impossible to actuate cylinder 47 by the accidental or intentional depression of foot pedal 46.

As will be apparent from the foregoing description, I have provided a means whereby the table 14 may be rapidly raised by regulated fluid pressure completely independently of the knife control mechanism.

1 have also provided a safety means which entirely eliminates the hazard of the accidental depression of the knife actuating foot pedal so that adjustments or maintenance work may be performed with the table in the raised position without danger of a moving knife.

While there has been described what is at present considered to be the preferred embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is therefore, aimed to cover all such changes and modifications as fall within the true scope and spirit of the invention.

Having thus described my invention, what I claim and desire to protect by Letters Patent is:

1. A cutting machine comprising a knife, means for driving said knife in a circuit around the edge of the article to be cut, a fixed form encompassed by said circuit, a table for carrying stock from which articles are to be cut into the path of said knife and for clamping said stock against said form, a first cylinder for moving said table toward and away from said form, clutch means for connecting and disconnecting said driving means from said knife, a second cylinder for actuating said clutch means, a regulated source of pressurized fluid, a first valve actuated by said second cylinder, and a manually operable selector valve, said first cylinder communicating with said regulated source through said first valve and through said selector valve in a first position of said selector valve, and said first cylinder communicating directly with said regulated source through-said selector valve in a second position of said selector valve.

2. A cutting machine comprising a knife, means for driving said knife in a circuit around the edge of the article to be cut, a fixed form encompassed by said circuit, a table for carrying stock from which articles are to be cut into the path of said knife and for clamping said stock against said form, a first cylinder for moving said table toward and away from said form, clutch means for connecting and disconnecting said drive means from said knife, a second cylinder, a piston rod slidably mounted within said second cylinder, a pivotally mounted bell crank having one arm pivotally secured to said piston rod and the other arm connected to said clutch means for actuating said clutch means, a regulated source of pressurized fluid, a first valve actuated by said second cylinder, and a manually operable selector valve, said first cylinder communicating with said regulated source through said first valve and through said selector valve in a first position of said selector valve, and said first cylinder communicating directly with said regulated source through said selector valve in a second position of said selector valve.

3. A cutting machine comprising a knife, means for driving said knife in a circuit around the edge of the article to be cut, a fixed form encompassed by said circuit, a table for carrying stock from which articles are to be cut into the path of said knife and for clamping said stock against said form, a first cylinder for moving said table toward and away from said form, clutch means for connecting and disconnecting said driving means from said knife, a second cylinder, a piston rod slidably mounted within said second cylinder, a pivotally mounted bell crank having one arm pivotally secured to said piston rod and the other arm connected to said clutch means for actuating said clutch means, a regulated source of pressurized fluid, a first valve, cam means operable by said piston rod for actuating said first valve, and a manually operable selector valve, said first cylinder communieating with said regulated source through said first valve 4. The cutting machine of claim 1 further comprising a selector lever for placing said selector valve in said first position or said second position and a safety valve means actuated by said selector lever when said selector valve is in said second position to prevent said second cylinder from communicating with a source of pressurized fluid.

5. The cutting machine of claim 4 further comprising a pilot valve, said pilot valve being actuated to an open position by said selector lever when said selector valve is in said second position and said safety valve means communicating with said regulated source when said pilot valve is in an open position.

References Cited by the Examiner UNITED STATES PATENTS 2,469,518 5/1949 Polleys 1286.6 2,484,907 10/ 1949 Purcell 91-4l2 X 2,918,902 12/1959 Robinson et a1 9l--412 X 3,006,006 10/ 1961 Polleys 1286.6

PATRICK D. LAWSON, Primary Examiner.

Claims (1)

1. A CUTTING MACHINE COMPRISING A KNIFE, MEANS FOR DRIVING SAID KNIFE IN A CIRCUIT AROUND THE EDGE OF THE ARTICLE TO BE CUT, A FIXED FORM ENCOMPASSED BY SAID CIRCUIT, A TABLE FOR CARRYING STOCK FROM WHICH ARTICLES ARE TO BE CUT INTO THE PATH OF SAID KNIFE AND FOR CLAMPING SAID STOCK AGAINST SAID FORM, A FIRST CYLINDER FOR MOVING SAID TABLE TOWARD AND AWAY FROM SAID FORM, CLUTCH MEANS FOR CONNECTING AND DISCONNECTING SAID DRIVING MEANS FROM SAID KNIFE, A SECOND CYLINDER FOR ACTUATING SAID CLUTCH MEANS, A REGULATED SOURCE OF PRESSURIZED FLUID, A FIRST VALVE ACTUATED BY SAID SECOND CYLINDER, AND A MANUALLY OPERABLE SELECTOR VALVE, SAID FIRST CYLINDER COMMUNICATING WITH SAID REGULATED SOURCE THROUGH SAID FIRST VALVE AND THROUGH SAID SELECTOR VALVE IN A FIRST POSITION OF SAID SELECTOR VALVE, AND SAID FIRST CYLINDER COMMUNICATING DIRECTLY WITH SAID REGULATED SOURCE THROUGH SAID SELECTOR VALVE IN A SECOND POSITION OF SAID SELECTOR VALVE.

Images