US1920252A

US1920252A - Presser foot mechanism

Info

Publication number: US1920252A
Authority: US
Inventors: Perley R Glass
Original assignee: United Shoe Machinery Corp
Current assignee: United Shoe Machinery Corp
Priority date: 1930-07-08
Filing date: 1930-07-08
Publication date: 1933-08-01
Anticipated expiration: 1950-08-01

Description

Aug. 1, 1933. P. R. GLASS PRESSER FOOT MECHANISM Filed July 8, 1930 2 Sheets-Sheet l Aug. 1, 1933. P. R. GLASS PRESSER FOOT MECHANISM Filed July 8, 1930 2 Sheets-Sheet 2 Patented Aug; 1, 1933 Ui ii i S'i ES PATENT Fries PREsssa Poor MsonANrsM Perley R. Glass, Wayland, Mass, assignor to United Shoe Machinery Corporation, Paterson, N. 5., a Corporation of New Jersey Application July 8, 1930. Serial No. 466,412

16 Claims. (01. 16l88.)

In perforating machines of the type shown. in

the Letters Patent to which reference has been made above, the intermittent feed of the work is accomplished by a punch and the presser-foot.

is arranged to hold the work during the return movement of the punch while the latter is out of the work. The machine operates at a'relatively high speed, thereby militating against a theoretically perfect fit between the moving parts and necessitating such play or looseness as is essential to the easy operation of the machine. Furthermore, the presser-foot in order to be effective must come down against the table supported work with substantial force.

An object of my invention is to improve the operation of the presser-foot mechanism by providing an improved mechanism whereby the ac tion of the presser-foot is softened and overthrow prevented, time at the same time enabling the machine to operate more quietly. In the illustrated construction, in accordance with a feature of the invention, the presser-foot is mounted on a supporting rod and the reciprocation of this rod is effected by means of a poweroperated pitman acting'through suitable springs to move the rod both toward and away from the work and commonly up and down. Thepresserfoot supporting rod is guided in a part of the frame of the machine and additionalsprings disposed between abutments on-said rod and said frame on opposite sides thereof are effective to prevent overthrow of the presser-foot supporting rod on the upstroke and to absorb the re-' bound of the presser-foot supporting rod, and hence to prevent its overthrow, on the down stroke.

These and other features of the invention will be more fully set forth in the following description in which reference is made to the accompanying drawings, in which Fig. 1 is a side elevation of a perforating machine embodying my invention;

Fig. 2 is a similar View partly in section on the line IIII of Fig. 3 and taken on an enlarged scale to show the presser-foot mechanism; and

Figs. 3 and 4 are end elevations with parts broken away and in section, also on an enlarged scale, showing the presser-foot in its raised and in its lowered positions respectively. I

. The illustrated perforating machine, as in the. patented construction, has a frame provided with an'ov rhanging hollow frame arm 10 (Figs.

. 1 and 2) having a cover plate 11. In this frame aresup'portedthe operating parts of the ma chine. The frame is also provided with an outwardly extending base 12 having a work table 14. Onthis base there is supported an anvil 16 over the top of which is guided a punch receiving strip 18 of paper or copper carried upon rolls 2i} and adapted to be releasably clamped in position abovethe anvil by means ofia manually operable clamping device 22. This'latter mechanism is more fully shown and described in my copending application for Letters Patent of the United States Serial No. 184,114, filed April 15, 1927, for improvements in perforating machines. A depending guard 24 is provided at the front of the machine and a piece of work 26 is laid on the work table over the strip 18 andheld there by a presser-foot 30 to receive the impact of the tool,--here a punch 32. The punch is held in a collet 34 (Figs. 3 and 4) which in this instance has a flanged top for reception in a dovetailed slot in the punch carrier 36. The punch collet 34 is held in position in this carrier by ,means of a clamp 38 hearing at thetop against the carrier 36 and at'the bottom against the collet 34 and held there by a clamp screw. The collet is also held against front to back movement by a flange 35 (Fig. 2) and a screw 37. The interior of the carrier 36 is hollow and has a tube 40 for carrying punchings 'to the rear and to one side of the point of operation.

As in the patented construction, the punch carrier 36 is supported for vertical reciprocation in a slide 42 movable from front to back (right to left in Fig. 1) upon bearingrods 44. Operation of this slide to effectfeeding movement of the work is effected by a cam operated lever &6 connected to the slidethrough a series of links and levers 48, 50, 52. The up and down or. punching movement is effected by means of a lever 54 pivoted in the frame 10 and oscillated by means of a link 56 attached'to the cam lever 58. This lever 54 is pinned to a cross rod 60 carrying at one end an'eccentric disk 62 having a crank pin 64 which fits in a block 66 slidably received in a suitable slot in a pitman 68. V

5 from the punch 32, and from front to back as may be convenient in operation of the machine. This rod 70 is slidably mounted. in an arm on the frame and near its upper end passes.

through a frame member 76 (Fig. 3). The rod 10 '70 'carries at its upper end an abutment block 78 which slidably engages in and fits a slot 80 (Fig. 2) near the top of the frame. This abutment block is clamped to the rod 70 by a set screw 82 and prevents rotation of the presser- 15, foot carrying rod in the frame as well as serving other purposes which will be described. On the rod 70 below the frame member 76, there is tightly clamped another abutment block 84 (Figs. 3 and i) which. extends out into the plane of operation of the pitman 68 and is recessed to receive the lower end of a spring 86 carried.

in a hollow portion 88 (Fig. 2) of the pitman and serving to transmit the force of the pitman vto the presser-foot rod to carry the presser-foot Tagainst the work. The upper end of the pitman 68 carries a rod 89 guided in the abutment block '73. In order that the pressure of the presserfoot upon the work may be regulated in accordance with the weight and character of the work 3GTbeing treated, the pitman is provided with an adjustable stop 90 (Fig. 2) which extendsinto the hollow portion 88 and bears against the upper portionof the spring 86. justable on the pitman by means of a screw 92 *.which is so positioned upon the outside of the machine that it is readily accessible. A look nut 94 is provided to maintain the adjustment which is made. At its lower end the pitman 68 is slottedto receive a screw 96 by means of which 4(I' there is adjustably attached to the pitman a guide block 98 (Figs. 3 and 4) freely slidable upon the presser rod 70. a

A coiled spring 100 surrounding the presserrod and interposed between the guide block 98 45.11 of the pitman and the lower abutment block 84 serves to transmit-the force of the pitman to the rod '70 and lift the presser-foot 30. This spring is of such a length, however, as shown in Fig. 4, that on the down stroke it no longer contacts 5QT5with the abutment 84; so that it does not interfere with the operation of the spring 86 as the latter urges the presser-foot against the work. Inasmuch as the upward movement imparted .to the presser-foot rod '70 is apt to cause an over- "throw of the same with resulting noise, I have provided a stiff spring 102 which surrounds the rod '70 between theabutment 84 and .the frame member '76. This stops or absorbs the overthrow on the up stroke. I have also provided another 607 spring 104 which surrounds the rod '70 between the frame member 76 and the upper abutment block '78. This catches the rebound and stops overthrow of thepresser rod on the down stroke. As will be noted from an inspection of Figs. 3 and 4, the

springs

102 and 104 are each constructed and arranged to be inactive when the other is under tension so that they effect the desired result without interfering with the usual operation of the machine and to a large extent eliminate the 1 noise commonly found in such mechanisms.

When it is desired manually to lift the presserfoot from the work at the completion of a line of perforations, the presser-foot rod 70 may be lifted by means of a treadle operated lever 110,

the forward end of which is positioned to under- This stop is ad-.

lie the head of a screw 112 threaded in the lower abutment block 84 and capable of being held in adjusted position by a lock nut 114.

It is believed that the operation of the machine will be clear from the description given and it will be noted that the power imparted to raise and lower the presser-foot rod 70 is delivered through springs and 36 respectively, while overthrow of the rod in either direction is taken up by the

springs

102 and 104.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a machine for performing step-by-step operations upon a shoe part, a frame, a presserfoot, a presser-foot support slidably mounted in the frame, power-operated means for moving said presser-foot up and down, resilent means interposed between said power-operated means and the presser-foot support whereby power of the said means is delivered to the presser--foot support through said resilient means, means for preventing overthrow of thepresser-foot support on the down stroke, and means for preventing an overthrow of the pressen-foct support on the up stroke.

2. In a perforating machine operating to perforate the work step by step, a frame, a presserfoot, 9. presser-foot supporting rod slidably mounted in the frame of the machine, abutments upon said rod upon opposite sides of the frame member, springs interposed between said abutments and said frame member. and cooperable therewith to avoid noise in the operation of the machine, and power-operated means for moving said presser-foot rod.

3. In a perforating machine operating to perforate the work step by step, a frame, a presserfoot, a presser-foot supporting rod slidably mounted in the frame of the machine, abutments on said rod upon opposite sides of the frame member, springs interposed between said abutments and said frame member and cooperable therewith to avoid noise in the operation of the machine, and power-operated means for moving said presser-foot supporting rod, said power means being resiliently'connected to the presserfoot rod.

4. In a machine for performing step-by-step operations upon a piece of work, a presser-foot, a presser-foot support mounted in said machine to carry the presser-foot toward and away from the work, springs operatively positioned between abutments on said presser-foot support and a relatively fixed portion of the machine to prevent overthrow of the support upon up and down movements thereof and thereby to avoid noise inv the operation of the machine, one of said springs being shorter than the total range of movement between its coacting abutment and the fixed part of the machine.

5. In a perforating machine, a frame, a rod slidably mounted in said frame, a presser-foot carried by said rod, abutments on said rod on opposite sides of said frame member, springs operatively positioned between said abutments and the frame member constructed and arranged to render one of said springs inoperative when the other is compressed, and power-operated means for raising and lowering said rod.

6. In a perforating machine, a frame, a rod slidably mounted in said frame, a presser-foot carried by said rod, an abutment on said rod, a power-operated slide on said rod, a resilient member interposed between said power-operated slide and said abutment constructed and arranged to be inactive when the presser-foot is pressed against the work and compressed when the presser-foot is moved away from the work, and resilient means for preventing overthrow of the presser-foot rod in either direction.

7. In a perforating machine, a frame, a rod slidably mounted in said frame, a presser-foot on said rod, a power-operated pitman for raising and lowering the rod, and means for guiding pitman relatively to said rod in a plane parallel thereto.

8. In a perforating machine, a frame, a rod slidably mounted vin said frame, a presser-foot on said rod, an abutment on said rod, and a power-operated pitman for raising and lowering the rod, said pitman being guided at one end by engagement with said abutment and at the other end by engagement with said rod.

9. In a perforating machine, a frame, a cylindrical rod siidabiy mounted in said frame, a presser-foot on said rod, an abutment block on said rod engaging a portion of the frame to prevent rotation of the rod, and a power-open ated pitman for raising and lowering the rod, said pit being guided at one end by engagement with said abutment block and at the other end by engagement with said rod.

10. In perforating machine, a frame, a rod slidably mounted in said frame, a presser-foot on said rod, an abutment on said rod, a poweroperated pitinan for raising and lowering the rod, said pitrnan being guided at one end by engagement with abutment and at the other end by engagement with said rod, and springs interposed between the opposite ends of said pitman and said presser-foot rod.

11. In a perforating machine, a frame, a rod slidably mounted in said frame, a presser-foot on said rod, an abutment on said rod, a power-- operated pitman for raising and lowering the rod, said pitman being guided at one end by engagement with said abutment and at the other end by engagement with said rod, and means for preventing overthrow of the presser-foot rod in both directions.

12. In a perforating machine, a frame, a rod slidably mounted in said framaa presser-foot on said rod, an abutment on said rod, a power-operated pitman for raising and lowering the rod, said pitman being guided at one end by engagement with said abutment and at the other end by engagement with said rod, springs interposed between the opposite ends of said pitman. and said presser-foot rod, and means for preventing overthrow of the, presser-foot rod in both directions.

13. In a perforating machine, a frame, a rod slidably mounted in said frame, a presser-foot' on said rod, abutments on said rod at opposite sides of a portion of said frame, a power-operated pitman having resilient means between said pitman and one of said abutments, and springs surrounding said rod in operative posi tion between said frame portion and said abutments to prevent overthrow of the rod.

14. In a perforating machine, a frame, a rod siidably mounted in said frame, a presser-foot on said rod, an abutment on said rod, springs upon opposite sides of the abutment and adapted to engage said abutment, power-operated means adapted to engage the springs for actuating said rod, and a manually-operated lever arranged for engagement with said abutment to lift said presser-foot to permit the insertion of a piece of work.

15. In a perforating machine, a frame, a rod slidably mounted in said frame, a presser-foot on said rod, an abutment carried by said rod at one side of the frame, a power-operated pitman having springs interposed between said pitman and said abutment whereby the operation of the pitman moves the rod to and fro, an adjustable stop upon said abutment, and a treadle-operated lever arranged for engagement with said stop whereby actuation of the lever will move the presser-foot away from the work.

16. In a'perforating machine, a frame, a rod slidably mounted in said frame, a presser-foot on said rod, an abutment carried by said rod at one side of the frame, a power-operated pitman having springs interposed between said pitman and said abutment whereby the operation of the pitrnan moves the rod to and fro, an adjustable stop upon said abutment, a treadle-operated lever arranged for engagement with said stop whereby actuation of the lever will move the presser-foot away from the work, and springs surrounding said rod for cooperation with opposite sides of said frame, thereby to prevent over.- throw of the rod.

PERLEY R. GLASS.